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Nitric oxide (NO) is critically involved in the regulation of a wide variety of physiological and pathophysiological processes. However, the role of NO in the pathogenesis of noise-induced hearing loss (NIHL) is complex and remains controversial. Here we reported that treatment of CBA/J mice with l -arginine, a physiological precursor of NO, significantly reduced noise-induced reactive oxygen species accumulation in outer hair cells (OHCs), attenuated noise-induced loss of OHCs and NIHL consequently. Conversely, pharmacological inhibition of endothelial nitric oxide synthase exacerbated noise-induced loss of OHCs and aggravated NIHL. In HEI-OC1 cells, NO also showed substantial protection against H 2 O 2 -induced oxidative stress and cytotoxicity. Mechanistically, NO increased S-nitrosylation of pyruvate kinase M2 (PKM2) and inhibited its activity, which thus diverted glucose metabolic flux from glycolysis into the pentose phosphate pathway to increase production of reducing equivalents (NADPH and GSH) and eventually prevented H 2 O 2 -induced oxidative damage. These findings open new avenues for protection of cochlear hair cells from oxidative stress and prevention of NIHL through NO modulation of PKM2 and glucose metabolism reprogramming. [Display omitted] • NO levels are increased compensatorily in the cochlea following noise exposure. • Supplementation with l -arginine increases NO levels and prevents NIHL in mice. • NO increases S-nitrosylation of PKM2 and NADPH production in HEI-OC1 cells. • NO protects against oxidative stress through glucose metabolism reprogramming. [ABSTRACT FROM AUTHOR]

Low-temperature PCMs are always the objects of prime investigations, however, the field of PCM’s application is not only limited to low temperatures. In this study, polyethylene glycol (PEG), lithium nitrate (LiNO 3 ), and sodium sulfate (Na 2 SO 4 ) were respectively employed as the low-, middle- and high-temperature storage medium. A series of novel form-stable phase change materials (fs-PCMs) were tailor-made by blending diatomite and the three PCMs via a vacuum impregnation method or a facile mixing and sintering method. Various techniques were employed to characterize their structural and thermal properties. The maximum loads of PEG, LiNO 3 , and Na 2 SO 4 in diatomite powder could respectively reach 58%, 60%, and 65%, while PCM melts during the solid–liquid phase transformation. SEM, XRD, and FT-IR results indicated that PCMs were well dispersed into diatomite pores and no chemical changes took place during the heating and cooling process. The prepared fs-PCMs were quite stable in terms of thermal and chemical manner even after a 200-cycle of melting and freezing. The resulting composite fs-PCMs were promising candidates to satisfy the application requirements for different temperature ranges due to their large latent heats and suitable phase change temperatures, as well as the excellent chemical compatibility, improved supercooling extent, and high thermal stability. [ABSTRACT FROM AUTHOR]

The effect of elevated temperature on solid particle impact erosion wear behavior of 5 mol% Yttria Stabilized Zirconia ceramics (5YSZ) was studied using corundum sand as solid impact particles, an impact angle of 90°, and an impact speed of 50–60 m/s. Moreover, the erosion wear mechanism of 5YSZ ceramics at different temperatures was discussed. The solid particle impact erosion wear rate of 5YSZ ceramics was increased from 0.10 mm 3 /g to 0.81 mm 3 /g when the temperature rose from room temperature to 1200 °C, and then decreased to 0.64 mm 3 /g at 1400 °C. The plastic deformation erosion mechanism of 5YSZ ceramics was observed from room temperature to 1400 °C, and the erosion wear mechanism of cracking in irregular crisscross patterns lead to the stepwise heightened flaky exfoliation of the material from 600 °C to 1200 °C, which became the main erosion wear mechanism. These results provide the theoretical base for extension of service life of 5YSZ ceramics by avoiding the conditions that lead to erosion wear mechanisms. [ABSTRACT FROM AUTHOR]

The effect of elevated temperature on solid particle impact erosion wear behavior of 5 mol% Yttria Stabilized Zirconia ceramics (5YSZ) was studied using corundum sand as solid impact particles, an impact angle of 90°, and an impact speed of 50–60 m/s. Moreover, the erosion wear mechanism of 5YSZ ceramics at different temperatures was discussed. The solid particle impact erosion wear rate of 5YSZ ceramics was increased from 0.10 mm 3 /g to 0.81 mm 3 /g when the temperature rose from room temperature to 1200 °C, and then decreased to 0.64 mm 3 /g at 1400 °C. The plastic deformation erosion mechanism of 5YSZ ceramics was observed from room temperature to 1400 °C, and the erosion wear mechanism of cracking in irregular crisscross patterns lead to the stepwise heightened flaky exfoliation of the material from 600 °C to 1200 °C, which became the main erosion wear mechanism. These results provide the theoretical base for extension of service life of 5YSZ ceramics by avoiding the conditions that lead to erosion wear mechanisms. [ABSTRACT FROM AUTHOR]

Shape-stabilized composite phase change materials (ss-CPCMs) composed of PEG (polyethylene glycol) and MCS (mesoporous calcium silicate) were prepared by a facile blending and impregnating method. Various techniques were employed to characterize their structural and thermal properties. The supercooling extent, melting time and solidifying time of the ss-CPCM were respectively 25%, 28.2%, and 27.3% less than those of PEG. The characterization results by DSC (Differential Scanning Calorimetry) technique indicated that the PEG/MCS ss-CPCM was a good candidate for building applications due to its large latent heat, suitable phase change temperature, and good thermal reliability. The crystallinity of PEG in the ss-CPCMs decreased with the increase of MCS content. We proposed the possible formation mechanism of PEG/MCS and concluded that the thermal properties of the PEG/MCS were influenced by the adsorption confinement of the PEG molecule chains in the mesoporous structure of MCS and the interference of MCS as an impurity in the perfect PEG crystallization. Interestingly, the melting temperature of the new ss-CPCMs could be adjusted from 34.16 °C to 58.13 °C and the solidifying temperature could be adjusted from 27.21 °C to 44.10 °C. Corresponding latent heats of the melting and solidifying processes were 97.79–128.18 J/g and 85.41–114.19 J/g, respectively. [ABSTRACT FROM AUTHOR]

Based on the analysis of energy structure and the development trends of advanced nuclear energy technology, combining the complementary advantages of nuclear energy and other energy sources in China, the Fluoride-Salt-cooled high-Temperature Advanced Reactor (FuSTAR) system has been proposed. FuSTAR system is designed to address production capacity issues in areas with energy shortages or resource concentration and can be combined with high-temperature process heat to achieve high-value-added processes such as hydrogen production. In this paper, the Tri-structural isotropic fuel combined with helical cruciform elements has been studied in detail on the neutron physics and thermal-hydraulic properties, and the flow and heat transfer experiment is carried out for the first time. The multilayer nonlinear programming method has been applied to the design of thermal transport systems. Then the optimal parameters and configuration of the thermoelectric conversion system are obtained by the superstructure optimization method. The inherent safety of FuSTAR is demonstrated through deterministic safety analysis. In addition, the iodine-sulfur cycle technology and the characteristics of tritium production are also analyzed. This study highlights the significant potential of integrating nuclear energy with other energy sources in an optimized energy-production system. • Multi-purpose reactor energy system for power - hydrogen - tritium production. • Over 50 % maximum thermal efficiency. • Simultaneous analysis of design, optimization, and safety. [ABSTRACT FROM AUTHOR]

In this study, we focus on important global issue containing both environmental pollution control and energy saving. High density polyethylene (HDPE) is utilized as supporting material to load paraffin, while Al2O3 nano-powder is added into composite behaving as thermal conductivity enhancement to form composite phase change materials (paraffin-Al2O3/HDPE composite PCMs). By the adsorption test and differential scanning calomeritry (DSC) curves, the loading ratio of paraffin in paraffin/HDPE composite is 60%, via taking phase change enthalpy and thermal conductivity into integrated consideration, the adding ratio of Al2O3 is 3% in paraffin-Al2O3/HDPE composite. And CMT4304 universal tester results manifest paraffin-Al2O3/HDPE composites have high compressive strength. For paraffin-Al2O3/HDPE composite with 3 mass% Al2O3, Fourier transformation infrared (FT-IR) result indicates no chemical interaction among raw materials but physical combination. DSC results identify composite PCM happens solid–solid phase transition at 33.3 ºC with enthalpy value of 10.7 J g−1 and melts at 48.8 ºC with enthalpy value of 95.1 J g−1, and thermal cycling measurements demonstrate the form-stable composite PCM with adequate stability after 300 times melting/freezing cycles. Furthermore, the thermal conductivity of paraffin/HDPE composite is enhanced by 119.4% to attain 0.419 Wm−1 K−1 after addition of Al2O3. To sum up, form-stable and tough paraffin-Al2O3/HDPE composite PCMs look promising for application in building field as solar energy utilization materials. [ABSTRACT FROM AUTHOR]

Using the solid-state method, a novel optical thermometer, RbCaLa 1-x (VO 4) 2 : x Eu3+ phosphor, was synthesized. Using X-ray diffraction, the phase of the RbCaLa 1-x (VO 4) 2 : x Eu3+ was confirmed. The microstructure was then observed in the SEM pattern. To estimate the temperature, the fluorescence intensity ratio (FIR) method was used. To explain the temperature-sensing properties, the absolute (Sa) and relative (Sr) sensitivities were calculated. The maximum Sa and Sr values were then determined as 2.215% and 1.125% at 473 and 423 K, respectively. After multiple heating and cooling processes, the FIR value corresponding to each temperature stabilized. This indicated the reliability of the FIR fitting formula. Subsequently, to examine the formula's accuracy, multiple temperature points ranging from 298 to 473 K were selected. The results demonstrated that the measurement error could be controlled in ±1.1 K. The difference was considerably lesser in the high-temperature region (400–430 K), and the error was in ±0.21 K. Under UV light, the colors of the RbCaLa 0.82 (VO 4) 2 :0.18Eu3+ phosphor and RbCaLa(VO 4) 2 matrix were somewhat different, and both considerably changed with temperature. All results showed that the Eu3+-doped RbCaLa(VO 4) 2 phosphor is a good candidate material as an optical temperature sensor and anti-counterfeiting coating. [ABSTRACT FROM AUTHOR]

[Display omitted] • NAD+ level was decreased in cisplatin treated cochlear organ of mice. • NAD+ modulators activated SIRT1, reduced hair cells loss and protected mice hearing. • TES-1025 with cisplatin increased mitochondrial contents in hair cells. • The protection of TES-1025 was blocked by SIRT1 inhibitor. Cisplatin, the most widely used platinum-based anticancer drug, often causes progressive and irreversible sensorineural hearing loss in cancer patients. However, the precise mechanism underlying cisplatin-associated ototoxicity is still unclear. Nicotinamide adenine dinucleotide (NAD+), a co-substrate for the sirtuin family and PARPs, has emerged as a potent therapeutic molecular target in various diseases. In our investigates, we observed that NAD+ level was changed in the cochlear explants of mice treated with cisplatin. Supplementation of a specific inhibitor (TES-1025) of α-amino-β-carboxymuconate-ε-semialdehyde decarboxylase (ACMSD), a rate-limiting enzyme of NAD+ de novo synthesis pathway, promoted SIRT1 activity, increased mtDNA contents and enhanced AMPK expression, thus significantly reducing hair cells loss and deformation. The protection was blocked by EX527, a specific SIRT1 inhibitor. Meanwhile, the use of NMN, a precursor of NAD+ salvage synthesis pathway, had shown beneficial effect on hair cell under cisplatin administration, effectively suppressing PARP1. In vivo experiments confirmed the hair cell protection of NAD+ modulators in cisplatin treated mice and zebrafish. In conclusion, we demonstrated that modulation of NAD+ biosynthesis via the de novo synthesis pathway and the salvage synthesis pathway could both prevent ototoxicity of cisplatin. These results suggested that direct modulation of cellular NAD+ levels could be a promising therapeutic approach for protection of hearing from cisplatin-induced ototoxicity. [ABSTRACT FROM AUTHOR]

Mammalian mitochondrial tRNA (mt-tRNA) plays a central role in the synthesis of the 13 subunits of the oxidative phosphorylation complex system (OXPHOS). However, many aspects of the context-dependent expression of mt-tRNAs in mammals remain unknown. To investigate the tissue-specific effects of mt-tRNAs, we performed a comprehensive analysis of mitochondrial tRNA expression across five mice tissues (brain, heart, liver, skeletal muscle, and kidney) using Northern blot analysis. Striking differences in the tissue-specific expression of 22 mt-tRNAs were observed, in some cases differing by as much as tenfold from lowest to highest expression levels among these five tissues. Overall, the heart exhibited the highest levels of mt-tRNAs, while the liver displayed markedly lower levels. Variations in the levels of mt-tRNAs showed significant correlations with total mitochondrial DNA (mtDNA) contents in these tissues. However, there were no significant differences observed in the 2-thiouridylation levels of tRNALys, tRNAGlu, and tRNAGln among these tissues. A wide range of aminoacylation levels for 15 mt-tRNAs occurred among these five tissues, with skeletal muscle and kidneys most notably displaying the highest and lowest tRNA aminoacylation levels, respectively. Among these tissues, there was a negative correlation between variations in mt-tRNA aminoacylation levels and corresponding variations in mitochondrial tRNA synthetases (mt-aaRS) expression levels. Furthermore, the variable levels of OXPHOS subunits, as encoded by mtDNA or nuclear genes, may reflect differences in relative functional emphasis for mitochondria in each tissue. Our findings provide new insight into the mechanism of mt-tRNA tissue-specific effects on oxidative phosphorylation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cancer is the number one enemy of human health. • Purely inorganic Polyoxometalates (POMs)-based compounds are effective against cancers, but still bear many drawbacks. • Novel POMs-based Inorganic organic hybrids have been confirmed to be more effective comparing with purely inorganic compounds. • These researches open us a new and meaningful direction of cancer drug treatments. Inorganic polyoxometalates (POMs) have drawn extensive attentions in the fields of chemical catalysis, biological medicine, and energy-store material. Due to their remarkable performances on bioactivity especial in anti-tumor and anti-virus, POMs have been regarded as a novel and potential anti-tumor drug material. However, the purely inorganic POMs would bear obvious defects when they were applied in drug therapy, such as low solubility in organism and high-toxic on normal cell. Therefore, researchers in recent have paid great efforts to improve the solubility and anti-tumor activity of POMs by grafting organic functional groups onto inorganic parent frame. At present, as new and potential anti-tumor drug compounds, these inorganic organic hybrids generated by combining POMs and organic groups have become a hot spot and have been deeply studied around the world. Here in this review, we would like to summarize the important works that reported in the last five years, mainly about the synthetic routes, basic structures, and anti-tumor effects of POMs-organism hybrids. [ABSTRACT FROM AUTHOR]

Abstract: Mitochondrial tRNA mutations are one of the important causes of both syndromic and non-syndromic deafness. Of those, syndromic deafness-associated tRNA mutations such as tRNALeu(UUR) 3243A>G are often present in heteroplasmy, while non-syndromic deafness-associated tRNA mutations including tRNASer(UCN) 7445A>G often occur in homplasmy or in high levels of heteroplasmy. These tRNA mutations are the primary mutations leading to hearing loss. However, other tRNA mutations such as tRNAThr 15927G>A and tRNASer(UCN) 7444G>A may act in synergy with the primary mitochondrial DNA mutations, modulating the phenotypic manifestation of the primary mitochondrial DNA mutations. Theses tRNA mutations cause structural and functional alteration. A failure in tRNA metabolism caused by these tRNA mutations impaired mitochondrial translation and respiration, thereby causing mitochondrial dysfunctions responsible for deafness. These data offer valuable information for the early diagnosis, management and treatment of maternally inherited deafness. [Copyright &y& Elsevier]

The structure of niobium-doped SrBiTiO was calculated by using density function and discrete variation method (DFT-DVM). By comparing the total energy of different doping sites, the total energy is found to be lower when Nb ion was substituted into the Ti site in the upper perovskite layer, which is far from the two bismuth (Bi) ions in the perovskite layer. The bonding strength of Nb (3)-O increases and the electronic conductivity of the SBT decreases after Nb doping. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2011 [ABSTRACT FROM AUTHOR]

Abstract: Yeast Saccharomyces cerevisiae MTO2, MTO1, and MSS1 genes encoded highly conserved tRNA modifying enzymes for the biosynthesis of carboxymethylaminomethyl (cmnm)5s2U34 in mitochondrial tRNALys, tRNAGlu, and tRNAGln. In fact, Mto1p and Mss1p are involved in the biosynthesis of the cmnm5 group (cmnm5U34), while Mto2p is responsible for the 2-thiouridylation (s2U34) of these tRNAs. Previous studies showed that partial modifications at U34 in mitochondrial tRNA enabled mto1, mto2, and mss1 strains to respire. In this report, we investigated the functional interaction between MTO2, MTO1, and MSS1 genes by using the mto2, mto1, and mss1 single, double, and triple mutants. Strikingly, the deletion of MTO2 was synthetically lethal with a mutation of MSS1 or deletion of MTO1 on medium containing glycerol but not on medium containing glucose. Interestingly, there were no detectable levels of nine tRNAs including tRNALys, tRNAGlu, and tRNAGln in mto2/mss1, mto2/ mto1, and mto2/mto1/mss1 strains. Furthermore, mto2/mss1, mto2/mto1, and mto2/mto1/mss1 mutants exhibited extremely low levels of COX1 and CYTB mRNA and 15S and 21S rRNA as well as the complete loss of mitochondrial protein synthesis. The synthetic enhancement combinations likely resulted from the completely abolished modification at U34 of tRNALys, tRNAGlu, and tRNAGln, caused by the combination of eliminating the 2-thiouridylation by the mto2 mutation with the absence of the cmnm5U34 by the mto1 or mss1 mutation. The complete loss of modifications at U34 of tRNAs altered mitochondrial RNA metabolisms, causing a degradation of mitochondrial tRNA, mRNA, and rRNAs. As a result, failures in mitochondrial RNA metabolisms were responsible for the complete loss of mitochondrial translation. Consequently, defects in mitochondrial protein synthesis caused the instability of their mitochondrial genomes, thus producing the respiratory-deficient phenotypes. Therefore, our findings demonstrated a critical role of modifications at U34 of tRNALys, tRNAGlu, and tRNAGln in maintenance of mitochondrial genome, mitochondrial RNA stability, translation, and respiratory function. [Copyright &y& Elsevier]

Abstract: The yeast MTO1 gene encodes an evolutionarily conserved protein for the biosynthesis of the 5-carboxymethylaminomethyl group of cmnm5s2U in the wobble position of mitochondrial tRNA. However, mto1 null mutant expressed the respiratory deficient phenotype only when coupled with the C1409G mutation of mitochondrial 15S rRNA. To further understand the role of MTO1 in mitochondrial RNA metabolism, the yeast mto1 null mutants carrying either wild-type (PS) or 15S rRNA C1409G allele (PR) have been characterized by examining the steady-state levels, aminoacylation capacity of mitochondrial tRNA, mitochondrial gene expression and petite formation. The steady-state levels of tRNALys, tRNAGlu, tRNAGln, tRNALeu, tRNAGly, tRNAArg and tRNAPhe were decreased significantly while those of tRNAMet and tRNAHis were not affected in the mto1 strains carrying the PS allele. Strikingly, the combination of the mto1 and C1409G mutations gave rise to the synthetic phenotype for some of the tRNAs, especially in tRNALys, tRNAMet and tRNAPhe. Furthermore, the mto1 strains exhibited a marked reduction in the aminoacylation levels of mitochondrial tRNALys, tRNALeu, tRNAArg but almost no effect in those of tRNAHis. In addition, the steady-state levels of mitochondrial COX1, COX2, COX3, ATP6 and ATP9 mRNA were markedly decreased in mto1 strains. These data strongly indicate that unmodified tRNA caused by the deletion of MTO1 gene caused the instability of mitochondrial tRNAs and mRNAs and an impairment of aminoacylation of mitochondrial tRNAs. Consequently, the deletion of MTO1 gene acts in synergy with the 15S rRNA C1409G mutation, leading to the loss of COX1 synthesis and subsequent respiratory deficient phenotype. [Copyright &y& Elsevier]

AbstractOxygen free radicals are produced during stress, are unstable, and potentially interact with other cellular components or molecules. This reactivity can influence cellular function, including a prolongation in tissue recovery following exercise. We tested the effect of ribose (d-ribose), a pentose carbohydrate, in a double-blinded, crossover study on markers of free radical production during hypoxic exercise. Seven healthy volunteers cycled at their lactate threshold for 25 minutes while inhaling 16% O2with a subsequent 60-minute resting period at room air. Subjects ingested either placebo or 7 g of ribose in 250 mL of water before and after the exercise session. Urinary malondialdehyde (MDA) and plasma reduced glutathione levels increased significantly during placebo ingestion (0.2 ± 0.03 nM/mg and 0.26 ± 0.29 μM, respectively) but were lower with ribose supplementation (0.04 ± 0.03 nM/mg and 0.38 ± 0.29 μM, respectively; P< .05). Uric acid levels were similar between groups (ribose vs. placebo, 4.55 ± 0.06 mg/dL vs. 4.67 ± 0.06 mg/dL). Ribose demonstrated a beneficial trend in lower MDA and reduced glutathione levels during hypoxic stress. [ABSTRACT FROM AUTHOR]

Mitochondrial tRNA 3'-end metabolism is critical for the formation of functional tRNAs. Deficient mitochondrial tRNA 3'-end metabolism is linked to an array of human diseases, including optic neuropathy, but their pathophysiology remains poorly understood. In this report, we investigated the molecular mechanism underlying the Leber's hereditary optic neuropathy (LHON)-associated tRNAAla 5587A>G mutation, which changes a highly conserved adenosine at position 73 (A73) to guanine (G73) on the 3'-end of the tRNA acceptor stem. The m.5587A>G mutation was identified in three Han Chinese families with suggested maternal inheritance of LHON. We hypothesized that the m.5587A>G mutation altered tRNAAla 3'-end metabolism and mitochondrial function. In vitro processing experiments showed that the m.5587A>G mutation impaired the 3'-end processing of tRNAAla precursors by RNase Z and inhibited the addition of CCA by tRNA nucleotidyltransferase (TRNT1). Northern blot analysis revealed that the m.5587A>G mutation perturbed tRNAAla aminoacylation, as evidenced by decreased efficiency of aminoacylation and faster electrophoretic mobility of mutated tRNAAla in these cells. The impact of m.5587A>G mutation on tRNAAla function was further supported by increased melting temperature, conformational changes, and reduced levels of this tRNA. Failures in tRNAAla metabolism impaired mitochondrial translation, perturbed assembly and activity of oxidative phosphorylation complexes, diminished ATP production and membrane potential, and increased production of reactive oxygen species. These pleiotropic defects elevated apoptotic cell death and promoted mitophagy in cells carrying the m.5587A>G mutation, thereby contributing to visual impairment. Our findings may provide new insights into the pathophysiology of LHON arising from mitochondrial tRNA 3'-end metabolism deficiency. [ABSTRACT FROM AUTHOR]

Two cyan-emitting phosphors with different bandwidths were successfully synthesized through the high-temperature solid-state method in a reducing atmosphere. The crystal structures, morphologies, and luminescence properties of the as-prepared phosphors were investigated. The Rietveld refinements of the powder X-ray diffraction (XRD) data demonstrated the single phase of the samples, and two crystallographic sites of La3+ were observed in the crystal structure. Under the excitation of UV light, both Ba 0.45 Ca 2.5 La 6 (SiO 4) 6 : 0.05 Eu2+ and Ba 1.45 Ca 1.5 La 6 (SiO 4) 6 : 0.05 Eu2+ phosphors emitted cyan light due to the 4f65 d1→4f7 transitions of the Eu2+ ion. The emission spectra could be well fitted by two component Gaussian peaks corresponding to two different coordination environments of the Eu2+ ions. The temperature-dependent photoluminescence spectra show a large difference on the thermal stability between the two phosphors. The two phosphors exhibit effective absorption of near-UV light and their internal quantum efficiencies (IQEs) were calculated as 31.5% and 42.4% under 295 nm UV-light excitation. The experimental results indicate that the novel cyan phosphors might have potential applications in white light-emitting diodes (LEDs) based on the near-UV LED chip. [ABSTRACT FROM AUTHOR]

Abstract  Increasing evidences have shown that pathogens might promote atherosclerosis and trigger acute myocardial infarction (AMI). But the conclusions from various studies on the correlation between previous influenza virus (IV) infection and AMI were inconsistent. We conducted a case-control study to assess the association of previous IV infection and AMI. Questionnaire survey was conducted to collect information about demographic characteristics and heart disease risk factors. Fasting blood sample was obtained to measure IgG antibodies to influenza virus A(IV-A), influenza virus B(IV-B), cytomegalovirus (CMV), herpes simplex virus type-1 (HSV-1) and type-2 (HSV-2), adenovirus (ADV), rubella virus (RV) and Chlamydia pneumoniae (CP) and measure the level of some biochemistry markers. Compared to controls, cases were more likely to have positive IgG antibodies to IV-A and IV-B (IV-A: OR, 3.3; 95%CI, 1.5 to 7.4; IV-B: OR, 17.2; 95%CI, 7.7 to 38.0). After adjustment for potential confounding variables, the risk of AMI was still associated with the presence of IgG antibodies to IV-A (adjusted OR, 7.5; 95%CI, 1.3 to 43.0) and IV-B (adjusted OR, 27.3; 95%CI, 6.6 to 113.8). The study supported the hypothesis that previous IV infection took part in the development of atherosclerosis and trigger the occurrence of AMI. [ABSTRACT FROM AUTHOR]

Abstract: We report here the characterization of the yeast mto2 null mutants carrying wild-type mitochondrial DNA or 15S rRNA C1049G allele. The amounts of mitochondrial tRNALys, tRNAGlu, tRNAGln, tRNALeu, tRNAGly and tRNAMet were markedly decreased but those of tRNAArg and tRNAHis were not affected in mto2 strains. The mto2 strains exhibited significant reduction in the aminoacylation of tRNALys, tRNALeu but almost no effect in those of tRNAHis. Interestingly, the strain carrying the C1049G allele exhibited an impairment of aminoacylation of those tRNAs. Furthermore, the steady-state levels of mitochondrial mRNA CYTB, COX1, COX2, COX3, and ATP6 were markedly decreased in mto2 strains. These data strongly indicate that unmodified tRNA caused by the deletion of MTO2 caused the instability of mitochondrial tRNAs and mRNAs and impairment of aminoacylation of tRNAs. [Copyright &y& Elsevier]

Abstract: We report here the identification and characterization of mouse mTERF encoding a mitochondrial transcription termination factor. A full-length mTERF cDNA has been isolated and the genomic organization of mTERF has been elucidated. The mouse mTERF gene containing two exons encodes a 380 residue protein with a strong homology to the mTERF-like proteins of human and other organisms, related to mitochondrial transcription termination. Northern blot analysis detected both 1.4 and 5.4kb transcripts. The mouse mTERF 1.4kb transcript agreeing with the size of cDNA is predominately expressed in heart and liver, but at extremely low level in other tissues. In addition, a ∼5.4kb transcript likely resulting from the retention of intron appears to express abundantly in heart and skeletal muscle, but at very low level in other tissues. Furthermore, immunofluorescence analysis of NIH3T3 cells expressing mTERF-GFP fusion protein demonstrated that the mouse mTERF localizes in mitochondrion. These observations suggest that the mouse mTERF is an evolutionarily conserved mitochondrial transcription termination factor, thereby promoting the termination of transcription in mitochondrial RNA. [Copyright &y& Elsevier]

We explore the phases of N=1 supersymmetric U(N) gauge theories with fundamental matter that arise as deformations of N=2 SQCD by the addition of a superpotential for the adjoint chiral multiplet. As the parameters in the superpotential are varied, the vacua of this theory sweep out various branches, which in some cases have multiple semiclassical limits. In such limits, we recover the vacua of various product gauge group theories, with flavors charged under some group factors. We describe in detail the structure of the vacua in both classical and quantum regimes, and develop general techniques such as an addition and a multiplication map which relate vacua of different gauge theories. We also consider possible indices characterizing different branches and potential relationships with matrix models. [Copyright &y& Elsevier]

Purpose: The present study aimed to explore the clinical characteristics of heparin-induced thrombocytopenia (HIT) after surgery for acute type A aortic dissection and perform a relevant prognostic analysis.Methods: After continuous observation and analysis of 204 patients who underwent acute type A aortic dissection, we found that blood platelets decreased significantly after surgery and that these patients can be suspected to suffer HIT based on relevant 4Ts scores. For these suspected HIT patients, a latex particle-enhanced immunoturbidimetric assay was conducted to detect heparin-induced antibodies. Perioperative clinical data of patients in HIT and non-HIT groups were recorded as were blood platelet counts, HIT antibody test results, 4Ts scores, thromboembolic complications, clinical prognosis and outcomes.Results: In the present study, 38 suspected HIT patients, 16 HIT patients and 188 non-HIT patients were selected in the clinical setting. Among them, HIT patients were found to have prolonged cardiopulmonary bypass time (223 min on average vs. 164 min) and delayed aortic cross-clamp time (128 min on average vs. 107 min), and these differences between HIT patients and non-HIT patients were significant (P < 0.05). Additionally, the HIT group required longer operation time and higher dose of heparin, but showing no statistical differences (P > 0.05). The transfusions of blood platelets in the HIT group and non-HIT group were 18.7 ± 5.0u and 15.6 ± 7.34 u, respectively. In the HIT group, the mechanic ventilation time and the length of ICU stay were longer comparing the non-HIT group(P < 0.05), though no significant differences in total length of stay or In-hospital mortality were observed (P > 0.05). The incidence of continuous renal replacement therapy in HIT group was higher than the non-HIT group (P < 0.05). Additionally,there were no significant differences in 24-h postoperative drainage or reoperation for bleeding in both group(P > 0.05). However, the HIT antibody titer in the HIT group was significantly higher than that in the Suspected HIT group (2.7 ± 0.8 U/mL vs. 0.3 ± 0.2 U/mL) (P < 0.05). Among patients diagnosed with HIT, the incidence of thromboembolism reached 31.5%.For example, two HIT patients newly developed thromboembolism in both lower extremities,and three patients experienced cerebral infarction.Conclusions: After surgery for acute type A aortic dissection, HIT patients developed postoperative complications, the duration of ventilatory support and length of ICU stay were extended, and the incidence of thromboembolism increased. HIT antibody detection and risk classification should be implemented for high-risk patients showing early clinical characteristics. [ABSTRACT FROM AUTHOR]

In the desert, plant diaspore spreading usually relies on both external vectors, such as wind, and internal factors, such as diaspore shape. Ammopiptanthus mongolicus is a heterocarpous shrub species in the cold desert in northwest China. Mature pods may have dehisced or not yet dehisced when abscising, and the dehiscent pods may be twisted or flattened. The propagation distances of diaspores might vary due to differences in their buoyancies in upward air and ground friction according to pod shape. The wind tunnel experiments were conducted to measure the horizontal displacement upon fruit dropping (D1) and the wind‐blown distance traveled by a fallen pod (D2) of A. mongolicus. A generalized linear mixed model and generalized linear model were used to test the effects of pod shape, release height, wind speed and ground substrate type on the spread distance of pods. D1 is jointly determined by the effects of release height and pod shape. Wind speed, pod shape and ground substrate type together affect D2. A twisted pod has higher dispersibility than a flat pod, and dehiscent pods spread further than indehiscent ones. The positive correlation of D1 and D2 indicates that the difference in pod shape additively broadens the range of seed‐spreading distance. Differential seed‐spreading properties could be adaptively advantageous to disperse the risks associated with diasporic dissemination compared with the maintenance of a single optimal dissemination characteristic. Thus, heterodiaspory is an advantageous adaptive characteristic for seed spreading in the windy, arid and harsh desert environment. [ABSTRACT FROM AUTHOR]

In the past, microcrystalline graphite (MG) was mainly used for the preparation of carbon enhancers and flame retardant, and is a low value-added inorganic mineral. There are very few reports of MG being compounded with Cu to produce friction materials. Carbon coated microcrystalline graphite/Cu (Carbon@MG/Cu) composites were prepared by coating MG with phenolic resin and mixing it with Cu. The effect of the phenolic resin coating on the mechanical and tribological properties of the composites was investigated by comparison with pure Cu, microcrystalline graphite/Cu (MG/Cu). The hardness and flexural strength of pure Cu were 39.8 HV and 72.3 MPa, respectively. The protection of the amorphous carbon shells led to a significant improvement in the mechanical properties of Carbon@MG/Cu, with hardness and flexural strengths of 72.3 HV and 103.8 MPa. The poor bonding between the MG and Cu severely affects its mechanical properties. Pure Cu has the highest wear rate (10.6 × 10−7(mm3/(N∙m)), while Carbon@MG/Cu has a stable coefficient of friction (0.19) and the lowest wear rate (4.3 × 10−7 (mm3/(N∙m)) compared to pure Cu and MG/Cu. We provide a method to prepare graphite/Cu composites with high mechanical and tribological properties based on low-cost MG, which helps to solve the problem of reuse of MG and increase its industrial added value. [Display omitted] • A low-cost core-shell structured Carbon@MG/Cu composites with enhanced mechanical and tribological properties. • The reuse of microcrystalline graphite and the increase of its industrial added value. To increase the mechanical and tribological properties of the composites. • The hardness and bending strength are increased by 44.9% and 39.8% respectively. [ABSTRACT FROM AUTHOR]

A novel g-C 3 N 4 composite photocatalyst was synthesized by one-step calcination using melamine and different functionalized multi-walled carbon nanotubes (MWCNT) as raw materials. The effect of additives on the photocatalytic performance of the composite g-C 3 N 4 has been investigated. The results showed that the incorporation of functionalized MWCNT led to a porous structure in g-C 3 N 4 , increasing the specific surface area and availability of active sites. The addition of hydroxylated/carboxylated MWCNT (HMWCNT/CMWCNT) affected the band structure of g-C 3 N 4 and reduced the band gap. The visible-light photocatalytic degradation efficiency of Rhodamine B (RhB) using g-C 3 N 4 composited with various types and amounts of MWCNT was evaluated. Among them, g-C 3 N 4 with 1 wt% CMWCNT showed the highest photocatalytic degradation efficiency of RhB and still had 92.71% photocatalytic activity after 5 cycles of degradation. • A novel composite g-C 3 N 4 with functionalized multi-walled carbon nanotubes was synthesized. • The porous structure in composite increases the availability of active sites. • The reduced band gap of the composite increases the separation rate of photogenerated electron-hole pair. • The composite exhibited 3.83-fold photocatalytic degradation efficiency with good cycling stability. [ABSTRACT FROM AUTHOR]

In the pursuit of enhancing the property of photocatalytic hydrogen production, strategies for enhancing light absorption and the separation and transport efficiency of photo-induced carriers have been studied. Perovskite photocatalyst has great application potential in the field of photocatalytic hydrogen production due to its special crystal structure. LaMn (1-x) Fe x O 3 (x = 0–0.08) perovskite nanofibers with diameters of 50–200 nm were synthesized by electrospinning, and their photochemical properties were investigated. The results of UV–Vis diffuse reflectance spectroscopy, PL spectroscopy, I-t, and EIS revealed that the doping with Fe could improve light absorption and reduce the recombination rate of photogenerated electron-hole pairs, and improve the separation and transfer efficiency of photogenerated electron-hole pairs, likely due to the increased concentration of oxygen vacancies caused by doping. Through optimization of the Fe doping amount, an improved hydrogen production efficiency of 767.71 μmol h−1 g−1 was achieved for LaMn 0·96 Fe 0·04 O 3 , which is 2.5 times the efficiency of undoped LaMnO 3 (300.74 μmol h−1 g−1). These results provide a new idea for the development of efficient photocatalysts for hydrogen production. • LaMnO3 nanofibers with various Fe-doping ratios were prepared by electrospinning. • Fe doping can adjust the crystal structure; change the oxygen vacancy concentration. • The prepared LaMn (1-x) Fe x O 3 nanofibers exhibited good photocatalytic activity. [ABSTRACT FROM AUTHOR]

Mitochondriamaintain a distinct pool of ribosomal machinery, including tRNAs and tRNAs activating enzymes, such as mitochondrial tyrosyl-tRNAsynthetase (YARS2). Mutations in YARS2, which typically lead to the impairment of mitochondrial protein synthesis, have been linked to an array of human diseases including optic neuropathy. However, the lack of YARS2mutation animal model makes us difficult to elucidate the pathophysiology underlying YARS2 deficiency. To explore this system, we generated YARS2 knockout (KO) HeLa cells and zebrafish using CRISPR/Cas9 technology. We observed the aberrant tRNATyr aminoacylation overall and reductions in the levels in mitochondrion- and nucleus-encoding subunits of oxidative phosphorylation system(OXPHOS), which were especially pronounced effects in the subunits of complex I and complex IV. These deficiencies manifested the decreased levels of intact supercomplexes overall. Immunoprecipitationassays showedthatYARS2 boundto specific subunits of complex I and complex IV, suggesting the posttranslational stabilization of OXPHOS. Furthermore, YARS2 ablation caused defects in the stability and activities of OXPHOS complexes. These biochemical defects could be rescued by the overexpression of YARS2cDNAin the YARS2KO cells. In zebrafish, the yars2KO larva conferred deficient COX activities in the retina, abnormal mitochondrial morphology, and numbers in the photoreceptor and retinal ganglion cells. The zebrafish further exhibited the retinal defects affecting both rods and cones. Vision defects in yars2KO zebrafish recapitulated the clinical phenotypes in the optic neuropathy patients carrying the YARS2 mutations. Our findings highlighted the critical role of YARS2 in the stability and activity of OXPHOS and its pathological consequence in vision impairments. [ABSTRACT FROM AUTHOR]

A shape‐stabilized composite phase change material (SS‐CPCM) with paraffin (PA) and biological porous carbon (BPC) was prepared. Freeze‐dried biological‐cellulose include abandoned pomelo peel (APP) and tangerine peel (ATP) were carbonized in vacuum at 800 °C to obtain BPC to be used as a matrix material to prevent PA leakage and enhance thermal conductivity. A vacuum impregnation process was utilized to obtain the SS‐CPCM. Scanning electron microscopy showed that BPC (carbonized APP is subsequently referred to as BPC1 and carbonized ATP as BPC2) has a porous, honeycomb‐like structure, and that the paraffin encapsulated by the pores is evenly distributed. The SS‐CPCM2 (made from ATP) had the highest thermal conductivity (2.10 W/m K), which is 1.89 and 10 times that of the SS‐CPCM1 (made using APP) and pure PA, respectively. Differential scanning calorimetry and thermo‐gravimetric analysis were applied to determine the thermal performance and thermal reliability of the SS‐CPCM. Therefore, the prepared SS‐CPCM has potential in the field of energy storage. [ABSTRACT FROM AUTHOR]

GdMnO 3 sample was firstly applied in the catalytic oxidation of VOC and furthermore, much highly active GdMn 2 O 5 /GdMnO 3 samples were in-situ generated by acid etching of GdMnO 3. In this work, GdMnO 3 material is successfully prepared using sol-gel method and GdMn 2 O 5 /GdMnO 3 materials are in-situ generated by acid treatment. These materials are investigated and applied as catalysts for oxygenated VOC complete oxidation. The evaluation results show that GdMn 2 O 5 /GdMnO 3 -1.00 exhibits a remarkable increase in catalytic activity (T 50% = 198 °C and T 90% = 225 °C) of 2-ethoxyethanol oxidation when compared with the initial sample GdMnO 3 (T 50% = 223 °C and T 90% = none). Characterization analyses show that acid treatment can result in the significant improvement of specific surface area from 20.502 m2·g−1 to 67.952 m2·g−1, abundant surface Mn4+ content and active oxygen, excellent reducibility at low temperature in GdMn 2 O 5 /GdMnO 3 -1.00 sample. In-situ DRIFTS results point out that the main functional groups such as ν as (OCO), ν as (COO), ν s (C O) are formed in the process of 2-ethoxyethanol oxidation over GdMn 2 O 5 /GdMnO 3 -1.00 sample and some by-products including ethanol, 2-ethoxyethyl acetate, acetic acid, carbonic acid, 2-ethoxyethyl 2-methoxyethyl ester, ethane and 1,1′-oxybis[2-methoxy-] can be produced at a reaction temperature of 200 °C. Additionally, in-situ DRIFTS studies indicate the presence of gas-phase O 2 plays a vital role in facilitating 2-ethoxyethanol deep oxidation to final products. [ABSTRACT FROM AUTHOR]

Leber's hereditary optic neuropathy (LHON) is a maternal inheritance of eye disease because of the mitochondrial DNA (mtDNA) mutations. We previously discovered a 3866T>C mutation within the gene for the ND1 subunit of complex I as possibly amplifying disease progression for patients bearing the disease-causing 11778G>A mutation within the gene for the ND4 subunit of complex I. However, whether and how the ND1 mutation exacerbates the ND4 mutation were unknown. In this report, we showed that four Chinese families bearing both m.3866T>C and m.11778G>A mutations exhibited higher penetrances of LHON than 6 Chinese pedigrees carrying only the m.3866T>C mutation or families harboring only the m.11778G>A mutation. The protein structure analysis revealed that the m.3866T>C (I187T) and m.11778G>A (R340H) mutations destabilized the specific interactions with other residues of ND1 and ND4, thereby altering the structure and function of complex I. Cellular data obtained using cybrids, constructed by transferring mitochondria from the Chinese families into mtDNA-less (p°) cells, demonstrated that the mutations perturbed the stability, assembly, and activity of complex I, leading to changes in mitochondrial ATP levels and membrane potential and increasing the production of reactive oxygen species. These mitochondrial dysfunctions promoted the apoptotic sensitivity of cells and decreased mitophagy. Cybrids bearing only the m.3866T>C mutation displayed mild mitochondrial dysfunctions, whereas those harboring both m.3866T>C and m.11778G>A mutations exhibited greater mitochondrial dysfunctions. These suggested that the m.3866T>C mutation acted in synergy with the m.11778G>A mutation, aggravating mitochondrial dysfunctions and contributing to higher penetrance of LHON in these families carrying both mtDNA mutations. [ABSTRACT FROM AUTHOR]

The study recruited 168 patients diagnosed with major depressive disorder (MDD). The nine-item Patient Health Questionnaire (PHQ-9) and Perceived Deficits Questionnaire for Depression (PDQ-D) were lower and the Digit Symbol Substitution Test (DSST) was higher in the community volunteers than those in MDD patients. Depression-related scores (17-item Hamilton Depression Rating Scale [HAMD-17], Clinical Global Impressions-Severity of Illness Scale [CGI-S], and PHQ-9), functioning-related scores (Sheehan Disability Scale [SDS]), and Work Efficiency and Activity Damage-Specific Health Problems questionnaire work productivity loss were decreased, and the quality of life-related scores (European Quality of life-5 Dimensions [EQ-5D] utility score) were increased in the MDD patients. PDQ-D was decreased and DSST was increased with the increase of follow-up time. Linear regression indicated that cognitive symptoms (PDQ-D and DSST) improved more slowly than depressive symptoms (PHQ-9). At baseline, PDQ-D was related with functioning (SDS and work productivity loss). PDQ-D and DSST were related with EQ-5D utility score. In addition, at month 6, PDQ-D was related with functioning (SDS and work productivity loss) and EQ-5D utility score. Cognitive impairment might be a risk for MDD and MDD-related changes in the functioning and quality of life. [ABSTRACT FROM AUTHOR]

Leber's hereditary optic neuropathy (LHON) is a maternally inherited eye disease. X-linked nuclear modifiers were proposed to modify the phenotypic manifestation of LHON-associated mitochondrial DNA (mtDNA) mutations. By whole-exome sequencing, we identified the X-linked LHON modifier (c.157C>T, p.Arg53Trp) in PRICKLE3 encoding a mitochondrial protein linked to biogenesis of ATPase in 3 Chinese families. All affected individuals carried both ND4 11778G>A and p.Arg53Trp mutations, while subjects bearing only a single mutation exhibited normal vision. The cells carrying the p.Arg53Trp mutation exhibited defective assembly, stability, and function of ATP synthase, verified by PRICKLE3-knockdown cells. Coimmunoprecipitation indicated the direct interaction of PRICKLE3 with ATP synthase via ATP8. Strikingly, cells bearing both p.Arg53Trp and m.11778G>A mutations displayed greater mitochondrial dysfunction than those carrying only a single mutation. This finding indicated that the p.Arg53Trp mutation acted in synergy with the m.11778G>A mutation and deteriorated mitochondrial dysfunctions necessary for the expression of LHON. Furthermore, we demonstrated that Prickle3-deficient mice exhibited pronounced ATPase deficiencies. Prickle3-knockout mice recapitulated LHON phenotypes with retinal deficiencies, including degeneration of retinal ganglion cells and abnormal vasculature. Our findings provided new insights into the pathophysiology of LHON that were manifested by interaction between mtDNA mutations and X-linked nuclear modifiers. [ABSTRACT FROM AUTHOR]

• 147 mitochondrial tRNA variants were identified in 887 Chinese Subjects with hearing loss. • 39 tRNA mutations (10 pathogenic and 29 likely pathogenic) were identified as putative deafness-associated tRNA variants. • 4.96% of the individuals carried the pathogenic/likely pathogenic tRNA mutations. • The mitochondrial tRNA mutations are the important causes of hearing loss. Mutations in the mitochondrial tRNAs have been reported to be the important cause of hearing loss. However, only a few cases have been identified thus far and the prevalence of mitochondrial tRNA mutations in hearing-impaired patients remain unclear. Here we performed the mutational analysis of 22 mitochondrial tRNA genes in a large cohort of 887 Han Chinese subjects with hearing loss by Sanger sequencing. The systemic evaluation of putative pathogenic variants was further carried out by frequency in controls (<1%), phylogenetic analysis, structural analysis and functional prediction. As a result, a total of 147 variants on 22 tRNA genes were identified. Among these, 39 tRNA mutations (10 pathogenic and 29 likely pathogenic) which absent or present <1% in 773 Chinese controls, localized at highly conserved nucleotides, or changed the modified nucleotides, could have potential structural alterations and functional significance, thereby considered to be deafness-associated mutations. Furthermore, 44 subjects carried one of these 39 pathogenic/likely pathogenic tRNA mutations with a total prevalence of 4.96%. However, the phenotypic variability and incomplete penetrance of hearing loss in pedigrees carrying these tRNA mutations indicate the involvement of modifier factors, such as nuclear encoded genes associated with mitochondrion biogenesis, mitochondrial haplotypes, epigenetic and environmental factors. Thus, our data provide the evidence that mitochondrial tRNA mutations are the important causes of hearing loss among Chinese population. These findings further increase our knowledge on the clinical relevance of tRNA mutations in the mitochondrial genome, and should be helpful to elucidate the pathogenesis of maternal hearing loss. [ABSTRACT FROM AUTHOR]

Graphite foams were prepared using foaming method and template method with nature flake graphite powder as main raw materials, sucrose as a foaming agent or binder, as well sodium chloride as a template. The compositions, microstructure, thermal properties and mechanical performance of the fabricated graphite foams were investigated by X-ray fluorescence spectrometer, scanning electron microscope, laser thermal conductivity meter, and electronic universal testing machine, respectively. The results show that water in binder played an important role in forming process of graphite foams. Graphite foams with controllable pore structure can be obtained by template method. The porosity of graphite foams increased with increasing the concentration of templating agent. With a fixed concentration of the templating agent the thermal diffusivity of the foams deceased with increasing the concentration of binder. Moreover, the obtained graphite foams has a minimum density of 288 kg/m3, a maximum porosity of 78% and a maximum thermal diffusivity of 7.14 × 10−6 m2/s. Two binding models of graphite foams prepared using template method has been proposed in the first time. This work provided an optimized processing for graphite foams with simple preparation, low-cost recyclable raw materials, and a promising thermal management material for many applications. Image 1 • New type of graphite foams were developed using natural flake graphite as main raw material. • Two binding models of graphite foams prepared using template method has been proposed. • Water can promote the pore-forming during the forming process of graphite foams. • The routes have superiority of simple, low-cost with recyclable raw materials. [ABSTRACT FROM AUTHOR]

Phase‐change materials (PCMs) have been widely investigated as candidates for thermal energy storage and solar thermal energy conversion. However, low thermal conductivity and poor shape stability during phase transition processes are detrimental to their practical applications. In this study, we designed composite PCMs based on carbon foam (CF) via the vacuum impregnation method to overcome these problems. CF with 3D interconnected microporous structures and good compressive strength was fabricated from phenolic resin (PF) using a combined process of carbonization and sacrificial template techniques. The developer material is considered a promising support material for PCMs. The as‐prepared polyethylene glycol/CF composite (PCC) exhibited a high energy‐storage density with a melting enthalpy of 135.7 J/g, and the thermal conductivity was enhanced by 109.8% compared to that of pure polyethylene glycol. In addition, the PCC showed excellent thermal stability and leakage‐proof performance after 100 heating/cooling cycles and good compressive strength. Because of the simple preparation process and low cost, PCC is a promising material for various thermal energy storage applications, especially in building energy storage systems. [ABSTRACT FROM AUTHOR]

The deafness-associated m.12201T>C mutation affects the A5-U68 base-pairing within the acceptor stem of mitochondrial tRNAHis. The primary defect in this mutation is an alteration in tRNAHis aminoacylation. Here, we further investigate the molecular mechanism of the deafness-associated tRNAHis 1220- 1T>C mutation and test whether the overexpression of the human mitochondrial histidyl-tRNA synthetase gene (HARS2) in cytoplasmic hybrid (cybrid) cells carrying the m.12201T>C mutation reverses mitochondrial dysfunctions. Using molecular dynamics simulations, we demonstrate that the m.12201T>C mutation perturbs the tRNAHis structure and function, supported by decreased melting temperature, conformational changes, and instability of mutated tRNA. We show that the m.12201T>C mutation-induced alteration of aminoacylation tRNAHis causes mitochondrial translational defects and respiratory deficiency. We found that the transfer of HARS2 into the cybrids carrying the m.12201T>C mutation raises the levels of aminoacylated tRNAHis from 56.3 to 75.0% but does not change the aminoacylation of other tRNAs. Strikingly, HARS2 overexpression increased the steady-state levels of tRNAHis and of noncognate tRNAs, including tRNAAla, tRNAGln, tRNAGlu, tRNALeu(UUR), tRNALys, and tRNAMet, in cells bearing the m.12201T>C mutation. This improved tRNA metabolism elevated the efficiency of mitochondrial translation, activities of oxidative phosphorylation complexes, and respiration capacity. Furthermore, HARS2 overexpression markedly increased mitochondrial ATP levels and membrane potential and reduced production of reactive oxygen species in cells carrying the m.12201T>C mutation. These results indicate that HARS2 overexpression corrects the mitochondrial dysfunction caused by the tRNAHis mutation. These findings provide critical insights into the pathophysiology of mitochondrial disease and represent a step toward improved therapeutic interventions for mitochondrial disorders. [ABSTRACT FROM AUTHOR]

Nuclear modifier genes have been proposed to modify the phenotypic expression of mitochondrial DNA mutations. Using a targeted exome-sequencing approach, here we found that the p.191Gly>Val mutation in mitochondrial tyrosyl-tRNA synthetase 2 (YARS2) interacts with the tRNASer(UCN) 7511A>Gmutation in causing deafness. Strikingly, members of a Chinese family bearing both the YARS2 p.191Gly>Val and m.7511A>G mutations displayed much higher penetrance of deafness than those pedigrees carrying only the m.7511A>G mutation. The m.7511A>G mutation changed the A4:U69 base-pairing to G4:U69 pairing at the aminoacyl acceptor stem of tRNASer(UCN) and perturbed tRNASer(UCN) structure and function, including an increased melting temperature, altered conformation, instability, and aberrant aminoacylation of mutant tRNA. Using lymphoblastoid cell lines derived from symptomatic and asymptomatic members of these Chinese families and control subjects, we show that cell lines harboring only the m.7511A>G or p.191Gly>Val mutation revealed relatively mild defects in tRNASer(UCN) or tRNATyr metabolism, respectively. However, cell lines harboring both m.7511A>G and p.191Gly>Val mutations displayed more severe defective aminoacylations and lower tRNASer(UCN) and tRNATyr levels, aberrant aminoacylation, and lower levels of other tRNAs, including tRNAThr, tRNALys, tRNALeu(UUR), and tRNASer(AGY), than those in the cell lines carrying only the m.7511A>G or p.191Gly>Val mutation. Furthermore, mutant cell lines harboring both m.7511A>Gand p.191Gly>Val mutations exhibited greater decreases in the levels of mitochondrial translation, respiration, and mitochondrial ATP and membrane potentials, along with increased production of reactive oxygen species. Our findings provide molecularlevel insights into the pathophysiology of maternally transmitted deafness arising from the synergy between tRNASer(UCN) and mitochondrial YARS mutations. [ABSTRACT FROM AUTHOR]

Needle‐like α‐Si3N4 with unique structures has potential application in both field emission devices and tips for atomic force microscopes. Single‐crystalline, α‐Si3N4 nanoneedles have been prepared by using an improved chemical vapor deposition (CVD) method at 1200°C for 3 hours. The phases, chemical composition, and microstructure of the as‐prepared products were determined by X‐ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM) equipped with EDS. The as‐synthesized products show a needle‐like morphology with hundreds of micrometers in length and nanometer‐featured tips. The nanoneedles show a α‐Si3N4@SiOx core‐shell heterostructure as characterized by TEM, with single‐crystalline α‐Si3N4 core and an insulating amorphous silicon oxide shell. The growth of α‐Si3N4 nanoneedles corresponds to vapor‐liquid‐solid cap‐growth and base‐growth mechanism. Photoluminescence (PL) properties of the products were also characterized. An obvious emission peak at 400 nm under 254 nm UV excitation was observed. The nanoneedle morphology and photoluminescence properties of the products have potentials to be used in future optoelectronic nanodevices. [ABSTRACT FROM AUTHOR]

Na 3 Gd(PO 4) 2 phosphors doped with rare-earth metal ions Ce3+ and Tb3+ were fabricated by the solid-state reaction method. Under the excitation of 340 nm light, the Ce3+-doped Na 3 Gd(PO 4) 2 phosphors exhibit a broad emission band ranging from 370 nm to 480 nm, which emitted blue light centered at 405 nm. When excited at 373 nm, the Tb3+-doped Na 3 Gd(PO 4) 2 phosphors presented a green light emission, including a strong peak located at 547 nm. In addition, both of the Na 3 Gd(PO 4) 2 : Ce3+ and Na 3 Gd(PO 4) 2 : Tb3+ phosphors showed excellent thermal stability at different temperatures, be specific in the Na 3 Gd(PO 4) 2 : Ce3+ emission intensities at 150 °C could maintain about 84 % and the Na 3 Gd(PO 4) 2 : Tb3+ could maintain about 92.9 % of those at room temperature. A prototype of the white light-emitting diodes lamp exhibiting bright white light was fabricated by using a 365 nm near-ultraviolet-emitting LED chip, combined with Na 3 Gd(PO 4) 2 : Ce3+ blue phosphors, Na 3 Gd(PO 4) 2 : Tb3+ green phosphors, and Na 3 Gd(PO 4) 2 : Eu3+ red phosphors, which produced a high color rendering index of 89.4, and a relatively low correlated color temperature of 5496 K. Moreover, the CIE point was calculated to be at (0.3332, 0.3438), locating in the white light region. These results indicate that the as-prepared phosphors can be considered as potential candidates for ultraviolet/near-ultraviolet light-excited white light-emitting diodes applications. • The Na 3 Gd(PO 4) 2 : Ce3+, Tb3+ phosphors were prepared with excellent thermal stability. • Both blue and green light phosphors have high internal quantum efficiency. • The CRI, CCT and CIE coordinate of the self-made w-LED has good performance. • The phosphors are potential for application in UV/NUV based w-LEDs. [ABSTRACT FROM AUTHOR]

Advances in solid-state white-light-emitting diodes (WLEDs) necessitate the urgent development of highly efficient single-phase phosphors with tunable photoluminescence properties. Herein, the Tm3+, Dy3+, and Sm3+ ions are incorporated into the orthorhombic NaGdTiO4 (NGT) phosphors, resulting in phosphors that fulfill the aforementioned requirement. The emission spectrum of Tm3+ ions overlaps well with the adsorption spectra of both Dy3+ and Sm3+ ions. Under the excitation at 358 nm, the single-phase NaGdTiO4: Tm3+, Dy3+, Sm3+ phosphor exhibits tunable emission peaks in the blue, yellow, and red regions simultaneously, resulting in an intense white-light emission. The coexisting energy transfer behaviors from Tm3+ to Dy3+ and Sm3+ ions and the energy transfer from Dy3+ to Sm3+ ions are demonstrated to be responsible for this phenomenon. The phosphors with multiple energy transfers enable the development of single-phase white-light-emitting phosphors for phosphor-converted WLEDs. [ABSTRACT FROM AUTHOR]

A novel robust and flexible superhydrophobic fluoropropyl methylsiloxane-dimethylsiloxane multi-block copolymer containing methacryloxyl group was synthesized via ring-opening polymerization, followed by macromolecular modification using 3-(trimethoxsilyl) propyl methacrylate (TMPMA). The propionyloxy group of MAc(PTFMS- alt -PDMS) could be crosslinked under UV irradiation, and its silicon methoxy group (-SiOCH 3) was simultaneously condensed under moisture ambient, so as to acquire both higher crosslink density and adhesion strength duo to the dual-curing mode. After coating and curing MAc(PTFMS- alt -PDMS) on the surface of cotton fabric, a robust superhydrophobic elastomer coating was obtained. The elastomer exhibited excellent mechanical properties with a tensile strength >4.0 Mpa and an elongation at break >300%. Moreover, the elastomer exhibited superhydrophobic properties (contact angle CA > 150o) and good adhesion properties (shear strength >3.7 Mpa) on various inorganic and organic substrates such as steel, glass, paper, and polyethylene (PE) films, with the assistant of the hydrophobic silica particles. The excellent flexibility and adhesive strength of the MAc(PTFMS- alt -PDMS) allowed a PE film to be bent at a large angle (120o). The results obtained here demonstrate that this material has good application prospects where flexible superhydrophobic coatings are desired. [ABSTRACT FROM AUTHOR]

The ADP/ATP carrier (AAC) is a transporter responsible for the equal molar exchange of cytosolic ADP and ATP synthesized within mitochondrial matrix across the mitochondrial membrane. Its primary structure consists of three homologous repeats, and each repeat contains a conserved motif that is shared by all members of the mitochondrial carrier family (MCF). Although these MCF motif residues cluster together in the crystal structure of AAC, detailed analyses on the interactions among the motif residues are still limited. In the present study, all-atom molecular dynamics (MD) simulations of up to 10 μs have been carried out on AAC, and interactions and structural dynamics of the MCF motif residues have been specifically investigated. Our simulations have revealed: i) a very asymmetrical electrostatic network at the bottom of the pocket of apo AAC, ii) the asymmetrical interactions between the Pro kink region and the [YWF][KR] G motif in three repeats, iii) the role of the conserved Arg residues in stabilizing the C-ends of the odd-numbered helices, iv) the structural change of the [YWF][KR] G motif and its potential involvement in substrate translocation process. Our results highlight the asymmetry of the MCF residues in the three repeats, which might contribute to the ability of the carriers to transport the asymmetrical substrates. Our observations provide microscopic basis for further research on the translocation mechanism of mitochondrial carriers. • An asymmetrical electrostatic network forms at the bottom of the pocket of apo AAC. • Pro kink-[YWF][RK]G interactions, between the first and the second part of MCF sequence motif, are asymmetrical in the three AAC repeats. • The three capping Arg residues are important in stabilizing the odd-numbered helices. • Structural change of the [YWF][RK]G portion of second part of AAC sequence motif is observed. [ABSTRACT FROM AUTHOR]

Mutations in mitochondrial DNA (mtDNA) have been associated with deafness and their pathophysiology remains poorly understood. In this study, we investigated the pathogenic mechanism of deafness-associated 7505A > G variant in the mitochondrial tRNASer(UCN). The m.7505A > G variant affected the highly conserved adenine at position 11 (A11), disrupted the highly conserved A11-U24 base-pairing of DHU stem of tRNASer(UCN) and introduced a tertiary base pairing (G11-C56) with the C56 in the TΨC loop. We therefore hypothesized that the m.7505A > G variant altered both structure and function of tRNASer(UCN). We demonstrated that the m.7505A > G variant perturbed the conformation and stability of tRNASer(UCN), as indicated by an increased melting temperature and electrophoretic mobility of the mutated tRNA compared with the wild type molecule. Using the cybrids constructed by transferring mitochondria from the Chinese family into mitochondrial DNA (mtDNA)-less cells, we demonstrated the m.7505A > G variant led to significantly decreased steady-state levels of tRNASer(UCN) in the mutant cybrids, as compared with those of control cybrids. The aberrant tRNASer(UCN) metabolism resulted in the variable decreases in mtDNA-encoded polypeptides in the mutant cybrids. Furthermore, we demonstrated that the m.7505A > G variant decreased the activities of mitochondrial respiratory complexes I, III and IV, markedly diminished mitochondrial ATP levels and membrane potential, and increased the production of reactive oxygen species in the mutant cybrids. These results demonstrated that the m.7505A > G variant affected both structure and function of tRNASer(UCN) and consequently altered mitochondrial function. Our findings highlighted critical insights into the pathophysiology of maternally inherited deafness, which is manifested by the aberrant tRNA metabolism. • tRNASer(UCN) 7505A > G variant were identified in a hearing-impaired Chinese family. • The tRNASer(UCN) 7505A > G variant caused the structural and functional alterations. • The m.7505A > G variant impaired mitochondrial translation, diminished ATP levels and increased the production of ROS. • Maternally inherited deafness, which is manifested by the aberrant tRNA metabolism. [ABSTRACT FROM AUTHOR]

In this study, tetradecanol–palmitic acid/expanded perlite composites containing carbon fiber (TD-PA/EP-CF CPCMs) were prepared by a vacuum impregnation method. Binary eutectic mixtures of PA and TD were utilized as thermal energy storage material in the composites, where EP behaved as supporting material. X-ray diffraction demonstrated that crystal structures of PA, TD, EP, and CF remained unchanged, confirming no chemical interactions among raw materials besides physical combinations. The microstructures indicated that TD-PA was sufficiently absorbed into EP porous structure, forming no leakage even in molten state. Differential scanning calorimetry estimated the melting temperature of TD-PA/EP-CF CPCM to 33.6 °C, with high phase change latent heat (PCLH) of 138.3 kJ kg−1. Also, the freezing temperature was estimated at 29.7 °C, with PCLH of 137.5 kJ kg−1. The thermal cycling measurements showed that PCM composite had adequate stability even after 200 melting/freezing cycles. Moreover, the thermal conductivity enhanced from 0.48 to 1.081 W m−1 K−1 in the presence of CF. Overall, the proposed CPCMs look promising materials for future applications due to their appropriate phase change temperature, elevated PCLH, and better thermal stability. [ABSTRACT FROM AUTHOR]

β‐SiC materials have been seen as the third‐generation semiconductor widely used in kinds of photoelectric device, high temperature electronics, and other fields. Compared with ordinary semiconductors, β‐SiC materials have huge potential application in replacing monocrystalline silicon in extreme environments because of their numerals extraordinary chemical and physical properties. Based on this, β‐SiC nanowires obviously are more desirable in any way. Here, we present a modified chemical vapor deposition (CVD) method to synthesis β‐SiC nanowires, which needs no protect gas, and transfer it to Si/SiO2 substrates equipped with Au electrodes. The microstructure of the as‐prepared samples is tested by field emission scanning electron microscopy (FESEM). The humidity sensing performance of electronic device is measured by electrochemical workstation test equipment. It shows that the resistance of β‐SiC nanowires increases with increasing environment humidity within very short response/recovery time‐0.5 seconds/0.5 seconds and also performs excellent cycling stability. Such advantage superiorities make it highly possible to apply β‐SiC nanowires into various environments. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Carbonization corn cobs were a perfect carrier matrix to form shape stabilized PCMs. • Carbonization corn cobs exhibit a highly porous structure comprising rough micropores. • Latent heat, stability, and thermal properties of PCMs were excellent. • The thermal conductivity of LA-SA/CNCC was 87.5% greater than that of LA-SA. Abstract In this study, novel form-stable composite phase change materials (FS-CPCMs) were prepared by the incorporation of a eutectic mixture of lauric-stearic acid (LA-SA) into carbonization corn cob (CNCC). CNCC served as a good supporting material that not only prevented the leakage of LA-SA but also enhanced its thermal conductivity. Scanning electron microscopy results demonstrated that CNCC exhibits a highly porous structure comprising rough micropores. The retention of 77.9 wt% of LA-SA in CNCC without leakage was observed. Differential scanning calorimetry results revealed that LA-SA/CNCC FS-CPCMs melt at 35.1 °C with a latent heat of 148.3 J/g and solidify at 29.7 °C with a latent heat of 144.2 J/g. The thermal conductivity of LA-SA/CNCC FS-CPCMs was approximately 87.5% greater than that of LA-SA. Thermogravimetric analysis and 200-cycle experiments indicated that the LA-SA/CNCC FS-CPCMs exhibit excellent thermal stability and form-stable performance. Therefore, the as-prepared LA-SA/CNCC FS-CPCMs demonstrate promise for building energy-efficiency applications. [ABSTRACT FROM AUTHOR]

Phase change materials (PCMs) require an excellent matrix support material such as porous carbon materials. Orange peel, a discarded, readily available raw material, could potentially be used to prepare biological porous carbon material (BPCM) with abundant pores of uniform size and strong loading capacity through a vacuum freeing method and a carbonization process under nitrogen atmosphere. Herein, paraffin (PA) was encapsulated into BPCM by vacuum impregnation method to obtain environmentally friendly; recyclable PA/carbonized-abandoned orange peel (CAOP) shape-stable PCMs (PA/CAOP SS-PCMs). CAOP was composed of amorphous carbon and a certain degree of graphitization occurred, the best of which was observed following carbonization at 1000 °C. Further, at this temperature, the pores were abundant and PA loading was sufficient. PA/CAOP SS-PCMs were shown to undergo simple physical loading with no chemical interactions and to have good thermal stability and a maximum loading percentage of 88.46%; the calculated maximum loading percentage was of 88.07%. The temperature and latent heat during the melting of PA/CAOP SS-PCMs were 47.68 °C and 180.25 J/g, respectively, and the solidification process occurred 34.47 °C and 177.55 J/g, respectively. The composite exhibited excellent thermal stability and reliability after 200 thermal cycles. Therefore, it has very broad application prospects and value in the fields of energy saving and emission reduction, including solar energy, air conditioning storage cooling systems, and building cladding. [ABSTRACT FROM AUTHOR]

Innovative syntheses of uniform and size-controlled chlorapatite crystals need to be developed. Molten salt synthesis is a simple process, which uses low temperatures and short reaction times to obtain synthesized powders with uniform chemical composition as well as good crystal morphology and high-phase purity. In this study, a molten salt synthesis was used to prepare ClAP microcrystallites at different temperatures, reaction times, and quantities of molten salt. ClAP microcrystallites with different sizes and morphologies were obtained, and the process parameters were optimized. The phase formation and morphologies of the ClAP microcrystallites were examined by X-ray powder diffraction and scanning electron microscopy. The results determined the optimal parameters, as follows: synthesis temperature, 600 °C; reaction time, 4 h; and ClAP/molten salt ratio, 1 : 3. The reaction time and the quantity of the molten salt, as well as the growth mechanism of the ClAP microcrystallites, were proposed based on the phase formation and morphologies of ClAP synthesized at various temperatures. ClAP phosphors activated using different ions (Sb3+, Eu2+, and Tb3+) were prepared by the molten salt method at 600 °C for 4 h with a ClAP/salt ratio of 1 : 3. The as-prepared ClAP:Sb3+/Eu2+/Tb3+ phosphors exhibited a blue-green emission (470 nm), a blue emission (460 nm), and a green emission (547 nm). Their excellent photoluminescence properties indicated their potential for application in white light emitting diodes. [ABSTRACT FROM AUTHOR]

The ZrN‐SiAlON composite powder was synthesized using low‐grade zircon and bauxite by carbothermal reduction nitridation at first and then ZrN‐SiAlON‐SiC‐C composite refractory were fabricated with the ZrN‐SiAlON powder, SiC particles, and a small amount of Si powder as raw materials and sucrose as the binder. The slag resistance of these composites in O2, N2 and Ar atmosphere was investigated by X‐ray diffraction, scanning electron microscopy, and energy dispersion spectra. The results show that the pores in the inside of ZrN‐SiAlON‐SiC‐C composite refractory were enlarged in oxygen atmosphere due to oxidation, which leads to the decrease in slag resistance. In argon atmosphere, blast furnace slag destroyed the sintered body of zircon, corundum, and cristobalite with the formation of CaZrO3, then infiltrated into and filled the pores inside the refractory to form a dense layer, which hindered the further erosion of the blast furnace slag. In the reducing atmosphere, the interfacial energy of the gas‐liquid phases became larger due to the reactions between blast furnace slag liquid and the gas, resulting in a larger wetting angle which prevented the erosion. [ABSTRACT FROM AUTHOR]