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Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Habitat fragmentation and the resulting decline in population size and density commonly reduce the reproduction of rare and threatened species. We investigated the impacts of population size and density on reproduction in more than 30 populations of Circaeaster agristis, a narrow endemic and threatened species, in 2010 and 2011. We also examined the effects of NND (nearest neighbor distance) and LNS (local neighbor size), within radii of 0.1 m, 0.2 m and 0.3 m, on reproduction in two of the populations in 2011. Results: Population size did not affect fruit (seed) number and fruit set in either year studied. Population density had an indirect negative effect on fruit number and fruit set as a consequence of a negative effect on plant size in 2010, but had no effect on fruit number and fruit set in 2011. Within populations, individual fruit number did not change, and individual fruit set increased independent of plant size, in response to increasing NND. Both individual fruit number and individual fruit set increased, independent of plant size, with increases in LNS within a 0.1 m radius, but did not change with increases in LNS within radii of between 0.1 m and 0.2 m radii or between 0.2 m and 0.3 m. Conclusions: The effect of habitat fragmentation on reproduction of C. agristis is scale-dependent. In contrast to the generally accepted idea that fragmentation reduces plant reproduction, reproductive success may increase in sparse populations or increase in response to decreases in LNS in C. agristis. [ABSTRACT FROM AUTHOR]

Nanopatterned sapphire substrates were fabricated by annealing of patterned Al thin films. Square-patterned Al thin films with the diagonal length of 600 nm, period of 1 um and height of ∼200 nm were obtained by the Laser Interference Lithography and Reactive Ion Etching. Patterned Al thin films were subsequently subjected to dual stage annealing due to the melting temperature of Al thin films (660 C). The first comprised a low temperature oxidation anneal. The hillocks formation on Al thin films was minimized with an oxidation annealing at 450 C for 24 h. The little change in the morphology of patterned Al thin films was observed at 450 C for 24 h. This was followed by a high temperature annealing to induce growth of the underlying sapphire single crystal to consume the oxide layer. The SEM results show the patterns were retained on sapphire substrates after high temperature annealing at less than 1200 C. The XRD and Raman results reveal that the orientation of island patterns by dual stage annealing of patterned Al thin films for 24 h at 450 C, and 1 h at 1000 C, was the same as that of the sapphire (0001) substrates. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Zhejiang University: Science A is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Large-scale nanopatterned sapphire substrates were fabricated by annealing of patterned Al thin films. Patterned Al thin films were obtained by soft UV-nanoimprint lithography and reactive ion etching. The soft mold with 550-nm-wide lines separated by 250-nm space was composed of the toluene-diluted polydimethylsiloxane (PDMS) layer supported by the soft PDMS. Patterned Al thin films were subsequently subjected to dual-stage annealing due to the melting temperature of Al thin films (660°C). The first comprised a low-temperature oxidation anneal at 450°C for 24 h. This was followed by a high-temperature annealing in the range of 1,000°C and 1,200°C for 1 h to induce growth of the underlying sapphire single crystal to consume the oxide layer. The SEM results indicate that the patterns were retained on sapphire substrates after high-temperature annealing at less than 1,200°C. Finally, large-scale nanopatterned sapphire substrates were successfully fabricated by annealing of patterned Al thin films for 24 h at 450°C and 1 h at 1,000°C by soft UV-nanoimprint lithography.

A preclinical trial identified 4 of 20 (20%) gastric cancer (GC) patient-derived xenografts responded to cetuximab. Genome-wide profiling and additional investigations revealed that high EGFR mRNA expression and immunohistochemistry score (3+) are associated with tumor growth inhibition. Furthermore, EGFR amplification were observed in 2/4 (50%) responders with average copy number 5.8 and .15 respectively. Our data suggest that a GC subtype with EGFR amplification and overexpression benefit from cetuximab treatment. [ABSTRACT FROM AUTHOR]

GaN nanoparticles were prepared on sapphire (0001) substrates with ZnO sacrificial layers by self assembly of GaO films in their reaction with NH. ZnO sacrificial layers with different thicknesses and GaO films were deposited on sapphire substrates in turn by a radio frequency (RF) magnetron sputtering system. Nitridation of the GaO films was then carried out in a quartz tube furnace. The effect of ZnO sacrificial layer thickness on the structure and optical properties of nanoparticles prepared by RF magnetron sputtering were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), and photoluminescence (PL). GaN nanoparticles with ZnO sacrificial layers of different thicknesses possess hexagonal wurtzite crystal structure and have a preferred orientation with c axis perpendicular to the sapphire substrates. XRD, SEM, and AFM results reveal that the better-crystallinity, uniform, and well-dispersed GaN nanoparticles (∼30 nm) without agglomeration were obtained with a ZnO sacrificial layer 300-nm thick. The PL result reveals that the optical properties of the GaN nanoparticles are improved with a ZnO sacrificial layer 300-nm thick. Therefore, we suggest that a ZnO sacrificial layer 300-nm thick is the most suitable condition for obtaining better-quality GaN nanoparticles with good luminescence performance. Moreover, the mechanism of the formation of GaN nanoparticles with ZnO sacrificial layers is also discussed. [ABSTRACT FROM AUTHOR]

The higher-order theory is extended to functionally graded beams (FGBs) with continuously varying material properties. For FGBs with shear deformation taken into account, a single governing equation for an auxiliary function F is derived from the basic equations of elasticity. It can be used to deal with forced and free vibrations as well as static behaviors of FGBs. A general solution is constructed, and all physical quantities including transverse deflection, longitudinal warping, bending moment, shear force, and internal stresses can be represented in terms of the derivatives of F. The static solution can be determined for different end conditions. Explicit expressions for cantilever, simply supported, and clamped-clamped FGBs for typical loading cases are given. A comparison of the present static solution with existing elasticity solutions indicates that the method is simple and efficient. Moreover, the gradient variation of Young’s modulus and Poisson’s ratio may be arbitrary functions of the thickness direction. Functionally graded Rayleigh and Euler–Bernoulli beams are two special cases when the shear modulus is sufficiently high. Moreover, the classical Levinson beam theory is recovered from the present theory when the material constants are unchanged. Numerical computations are performed for a functionally graded cantilever beam with a gradient index obeying power law and the results are displayed graphically to show the effects of the gradient index on the deflection and stress distribution, indicating that both stresses and deflection are sensitive to the gradient variation of material properties. [ABSTRACT FROM AUTHOR]

Non-Fourier effect is important in heat conduction in strong thermal environments. Currently, generally-purposed commercial finite element code for non-Fourier heat conduction is not available. In this paper, we develop a finite element code based on a hyperbolic heat conduction equation, which includes the non-Fourier effect in heat conduction. The finite element space discretization is used to obtain a system of differential equations for the time. The transient responses are obtained by solving the system of differential equations, based on the finite difference, mode superposition, or exact time integral. The code is validated by comparing the numerical results with exact solutions for some special cases. The stability analysis is conducted and it shows that the finite difference scheme is an ideal method for the transient solution of the temperature field. It is found that with mesh refining (decreasing mesh size) and/or high-order elements, the oscillation in the vicinity of sharp change vanishes, and can be essentially suppressed by the finite difference scheme. A relationship between the time step and the space length of the element was identified to ensure that numerical oscillation vanishes. [ABSTRACT FROM AUTHOR]

Cracks and porosities inside the piezoelectric materials can weaken the electromechanical coupling effect, and hence influence the electromechanical coupling behavior of piezoelectric materials considerably. This paper studies the effect of internal cracking on the effective properties of piezoelectric media. It focuses on the piezoelectric medium of finite size with finite crack. The mechanical and electric fields in the piezoelectric material and the crack are formulated by singular integral method. Effects of crack size, medium border, and electric permeability of the crack on the overall electromechanical properties of the piezoelectric material are obtained and displayed graphically. In addition, the crack tip coupling electromechanical field intensity factors are also presented as they are not available in open literature for a finite crack in a finite piezoelectric media. [ABSTRACT FROM AUTHOR]

AbstractAim:To Characterize a new human lung cancer cell line Am1010, derived from drug-surviving cells (DSCs).Methods:The Am1010 cell line was established after 4 cycles of chemotherapy from an arm muscle metastasic tumor of a patient diagnosed with lung adenocarcinoma. The cell line has been remained in continuous culture for more than one year during this study.Results:The Am1010 cell line demonstrated in vitro multi-drug-resistance to cisplatin, taxol, and gefitinib. The Am1010 cell doubling time without drug treatment was 42.395 h. The IC50 value of cisplatin was 4.299 μmol/L and >10 μmol/L for the Am1010 and P0318 (a cell line derived from non-DSCs) cells, respectively. The IC50 value of taxol was 0.067 μmol/L and >1 μmol/L for the Am1010 and P0318 cells, respectively. The IC50 value of gefitinib was 15.233 μmol/L and >70 μmol/L for Am1010 and P0318 cells, respectively. 11 genes involved in the focal adhesion and cell adhesion pathways were found to be differentially expressed. The cells of Am1010 have a significantly larger chromosome number than most lung cancer cell lines.Conclusion:This novel DSCs derived lung cancer cell line will be a valuable in vitro tool for the investigation of lung cancer drug resistance and metastasis. [ABSTRACT FROM AUTHOR]

We evaluate the incidence and risk factors associated with positive soft tissue surgical margins (STSM) and determine the association with various surgical and pathological characteristics and clinical outcomes in patients undergoing radical cystectomy (RC) for bladder cancer. From November 1971 to December 2005, 1,591 patients with primary transitional cell carcinoma (TCC) of the bladder underwent RC, with an extended bilateral pelvic lymphadenectomy and urinary diversion. A positive STSM was defined as tumor identified at the inked perivesical soft tissue surrounding the cystectomy specimen. Data were analyzed according to various clinical and pathologic variables, and survival analysis was performed. A total of 18 patients (1%) demonstrated pathologic evidence of a positive STSM following RC. Positive STSM were significantly associated with lymphovascular invasion, advanced pathologic stage, lymph node involvement, extent of nodal involvement and lymph node density. No patient with an organ-confined primary bladder tumor had a positive STSM, while 3% with extravesical tumor extension demonstrated a positive STSM. Recurrence-free and overall survival at 5 and 10 years for patients with a positive STSM was 29 and 22%, and 29 and 11%, respectively ( p < 0.001). A positive STSM increased the risk of recurrence by threefold and the overall risk of death by 2.6 times. Only nine patients (1%) without evidence of nodal involvement had a positive STSM with a worse survival compared to those same pathologic subgroup and negative STSM. Nine patients (2%) with lymph node tumor involvement had positive STSM and also demonstrated significantly worse survival. Although a positive STSM was present in only 1% of patients undergoing a RC for TCC of the bladder, it was found to be an independent risk factor for advanced disease, lymph node involvement and tumor progression with worse survival. A dedicated effort should be made to avoid a positive STSM at the time of RC. [ABSTRACT FROM AUTHOR]

Abstract  Cellulose multi-filament fibers have been spun successfully on a pilot plant scale, from a cellulose dope in 7 wt% NaOH/12 wt% urea aqueous solution pre-cooled to −12 °C. Coagulation was accomplished in a bath with 10 wt% H2SO4/12 wt% Na2SO4 and then 5 wt% H2SO4 aqueous solution. By using different finishing oil, including H2O, 4% glycerol aqueous solution, 2% polyvinyl alcohol (PVA) aqueous solution, 2% polyethylene glycol octyl phenylether (OP) aqueous solution, mobol and 2%glycerol/1%PVA/1%OP aqueous solution (PGO), we prepared six kinds of the cellulose multi-filaments, with tensile strength of 1.7–2.1 cN/dtex. Their structure and properties were investigated with scanning electron microscope (SEM), 13C NMR solid state, wide-angle X-ray diffraction (WAXD) and tensile testing. The cellulose fibers treated with PGO possessed higher mechanical properties and better surface structure than others. Interestingly, although the orientation of the cellulose multi-filaments is relatively low, the tensile strength of the single-fiber was similar to that of Lyocell. It was worth noting that the dyeability of the multi-filament fibers was superior to viscose rayon. [ABSTRACT FROM AUTHOR]

Abstract  Fe3O4/SiO2/poly (N-isopropylacrylamide-co-N,N-dimethylaminoethyl methacrylate) [P(NIPAM-co-DMA)] multiresponsive composite microspheres with core–shell structure were synthesized by template precipitation polymerization. First, the magnetite nanoparticles were coated with silica and then modified with 3-(trimethoxysilyl)-propyl methacrylate (MPS). Subsequently, the Fe3O4/SiO2 particles grafted with MPS were used to seed the precipitation copolymerization of NIPAM and DMA. The composite microspheres with core–shell structure were superparamagnetic, pH-sensitive, and thermoresponsive. The swelling ratio (D25 �C, pH = 3/D50 �C, pH = 9)3 coupling of pH and temperature increased up to 21.2, which was much higher than that without comonomer DMA. [ABSTRACT FROM AUTHOR]

Abstract  Magnetoelectroelastic materials are inherently brittle and prone to fracture. Therefore, it is important to evaluate the fracture behavior of these advanced materials. In this paper, a periodic array of cracks in a transversely isotropic magnetoelectroelastic material is investigated. Hankel transform is applied to solve elastic displacements, electric potential and magnetic potential. The problem is reduced into a system of integral equations. Both impermeable and permeable crack-face electromagnetic boundary conditions assumptions are investigated. Quantities of the stress, electric displacement and magnetic induction and their intensity factor are obtained. Effect of the crack spacing on these quantities is investigated in details. [ABSTRACT FROM AUTHOR]

To investigate the efficacy and relationship between plasma concentrations at the end of infusion ( C end of infusion) and toxicity profile of fixed-dose-rate gemcitabine plus carboplatin in chemotherapy-naive patients with advanced non-small-cell lung cancer (NSCLC). Patients were given gemcitabine by 120 min infusion [at a fixed dose rate (FDR) of 10 mg/m2/min] on days 1 and 8 of a 21-day cycle, immediately followed by carboplatin AUC 5 by 4 h infusion on day 1. C end of infusion of gemcitabine was determined by ion-pair reversed-phase high-performance liquid chromatography (HPLC). By the close-out date, in our study population, the estimated median time to tumor progression (TTP) was 7 months (95% CI 4–10 months), median overall survival (OS) was 12 months (95% CI 11.2–12.8 months). The mean value of C end of infusion of 21 eligible patients was 16.48 ± 8.07 μmol/l (range 27.43–2.87 μmol/l). The main hematological toxicities were transient grade 3–4 thrombocytopenia. The mean percentages of reduction of WBC, NEC, PLTC and Hb of 21 eligible patients were 38.3 ± 38.1%, 31.3 ± 73.6%, 31.8 ± 53.5% and 12.0 ± 12.2%, respectively. The analysis of the C end of infusion of gemcitabine and the percentage of reduction in WBC showed a significant correlation ( r 2 = 0.4575; p < 0.05). A significant correlation ( r 2 = 0.5671; p < 0.05) was also observed between the percentage of reduction of PLTC and C end of infusion of gemcitabine infusion. The clinical data in this trial supports the further evaluation the regimen in advanced NSCLC patients, due to its predictable kinetic behavior and less severe toxicity profile than expected. [ABSTRACT FROM AUTHOR]

Abstract  The morphology and structure of the regenerated cellulose membranes prepared from its NaOH–urea aqueous solution by coagulating with 5 wt% H2SO4–10 wt% Na2SO4 aqueous solution with different temperatures and times were investigated. The pore size, water permeability and physical properties of the membranes were measured with scanning electron micrograph (SEM), wide X-ray diffraction (WXRD), Fourier transfer infrared spectroscopy (FTIR), flow rate method, and tensile testing. The SEM observation revealed that the structure and pore size of the membranes changed drastically as a function of the coagulation temperature. The membranes coagulated at lower temperatures tended to form the relatively small pore size than those at higher temperatures. On the contrary, the membranes coagulated at different times exhibited similar pore size. Interestingly, the mean pore size and water permeability of the membranes increased from 110 nm with standard deviation (SD) of 25 nm and 12 ml h−1 m−2 mmHg−1 respectively to 1,230 nm with SD of 180 nm and 43 ml h−1 m−2 mmHg−1 with an increase in coagulation temperature from 10 to 60C. However, the membranes regenerated below 20C exhibited the dense structure as well as good tensile strength and elongation at break. The result from FTIR and ultraviolet-visible (UV-vis) spectroscopy indicated that the relatively strong intermolecular hydrogen bonds exist in the cellulose membranes prepared at lower coagulation temperatures. This work provided a promising way to prepare cellulose materials with different pore sizes and physical properties by controlling the coagulation temperature. [ABSTRACT FROM AUTHOR]

A simple method has been devised for immobilization of acetylcholinesterase (AChE)—covalent bonding to a multiwall carbon nanotube (MWNT)–cross-linked chitosan composite (CMC)—and a sensitive amperometric sensor for rapid detection of acetylthiocholine (ATCl) has been based on this. Fourier-transform infrared spectroscopy proved that the native structure of the immobilized enzyme was preserved on this chemically clean and homogeneous composite film, because of the excellent biocompatibility and non-toxicity of chitosan. Glutaraldehyde was used as cross-linker to covalently bond the AChE, and efficiently prevented leakage of the enzyme from the film. Because of the inherent conductive properties of the MWNT, the immobilized AChE had greater affinity for ATCl and excellent catalytic effect in the hydrolysis of ATCl, with a $$K^{{{\text{app}}}}_{{\text{m}}} $$ value of 132 μmol L−1, forming thiocholine, which was then oxidized to produce a detectable and rapid response. Under optimum conditions the amperometric current increased linearly with the increasing concentration of ATCl in the range 2.0–400 μmol L−1, with a detection limit of 0.10 μmol L−1. Fabrication reproducibility of the sensor was good and the stability was acceptable. The sensor is a promising new tool for characterization of enzyme inhibitors and for pesticide analysis. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Purpose: To assess the effects of sperm DNA damage, as determined by the TUNEL assay and the SCSA respectively, on the outcomes of IVF/ICSI treatment. Methods: A Medline search (from Jan 1978 to Apr 2006) was performed, together with a manual search of the bibliographies of retrieved original papers and review articles. 8 articles met all inclusion/exclusion criteria, of which, 5 used the TUNEL assay and the other 3 used the SCSA. All these articles were included in separate meta-analysis. The meta-analysis was conducted using the RevMan software with fixed-effect model or random-effects model. Results: As for articles using the TUNEL assay, the pooled results of IVF outcomes indicated that the clinical pregnancy rate (RR 0.68, 95% CI 0.54 to 0.85, P=0.006), but not the fertilization rate (RR 0.79, 95% CI 0.54 to 1.16, P=0.23) decreased significantly for patients with high degree of sperm DNA damage compared with those with low degree of sperm DNA damage. RRs of the ICSI outcomes indicated that there was no significant difference in either fertilization rate (RR 1.03, 95% CI 0.89 to1.18, P=0.70) or clinical pregnancy rate (RR 0.76, 95% CI 0.55 to 1.04, P=0.09) between these two groups. As for the SCSA papers, the pooled results showed no significant effects of sperm DNA damage on the clinical pregnancy rate after IVF (RR 0.58, 95% CI 0.25 to 1.31, P=0.19) or ICSI (RR 1.18, 95% CI 0.81 to 1.74, P=0.38). Conclusion(s): Our meta-analysis indicates that sperm DNA damage, as assessed by the TUNEL assay, significantly decreases only the chance of IVF clinical pregnancy, but not that of either IVF fertilization or ICSI fertilization or ICSI clinical pregnancy. Besides, our results also reveal that sperm DNA damage, when assessed by the SCSA, has no significant effect on the chance of clinical pregnancy after IVF or ICSI treatment. [ABSTRACT FROM AUTHOR]

Uniform nanospheres were prepared by dispersion copolymerization of n-butyl methacrylate (BMA) with poly(ethylene glycol) (PEG) macromonomers with p-vinylbenzyl end groups in various ethanol/water media. Particle size effects were investigated as a function of macromonomer molecular weight, solvent composition, and initial monomer and initiator concentrations. Hydrodynamic nanoparticle radii (Rh) followed the exponential law of initial initiator, St-PEG macromonomer and BMA concentrations. When reaction conditions were properly chosen, nanosphere particle size was controlled from ca. 40 to 750 nm in diameter. It was found that nanospheres swelled in ethanol/water dispersion media and the degree of swelling responded sensitively to solvent composition changes and reached a maximum at ethanol contents of 40-50 vol %. [ABSTRACT FROM AUTHOR]

The simultaneous combustion synthesis and hot compaction of Ti, C and Ni powders under a hydrostatic pressure was undertaken to fabricate fully dense TiC-Ni functionally graded materials (FGM) in a single processing operation. The composition gradient was optimized by finite element analysis and obtained by stacking different powder mixtures of desired compositions. X-ray diffraction, scanning electron microscopy and microprobe analysis were employed to investigate the crystalline phase, microstructure and Ni distribution. Experimental results demonstrate that the combustion reaction was complete and the final products contained the phases TiC and Ni only, the microstructure varies coherently throughout the specimen with no distinct interface. The physical and mechanical properties were measured as a function of composition. It was found that the properties of the FGMs were dependent on the Ni content and approached the maximum values for the relative density, hardness and flexural strength at room temperature when the Ni content was increased to 20 wt%. The maximum in fracture toughness value was found in the TiC-30 wt% Ni material. [ABSTRACT FROM AUTHOR]

Simultaneous combustion synthesis reaction and compaction of Ti, C, and Ni powders under a hydrostatic pressure was carried out to fabricate dense TiC-Ni functionally graded materials (FGMs) in a single processing operation. Scanning-electron microscope (SEM) and microprobe analysis (EPMA) was employed to investigate the microstructure and composition distribution. Experimental results demonstrate that Ni and Ti composition varies continuously and gradually along the thickness of the reacted sample, remarkably different from stepwise type prior to combustion synthesis. The constituents are continuous in microstructure everywhere and no distinct interaction occurs in TiC-Ni FGM. Moreover, the thermal physical and mechanical properties were measured as a function of composition. It was found that the properties of the FGMs were dependent on Ni content. The residual thermal stress of TiC-Ni FGM and dual-laminate non-FGM cooled to room temperature after combustion synthesis has been analyzed by finite element method. TiC-Ni FGM shows distortion and thermal stress relaxation, which is in striking contrast to the layered TiC-Ni non-FGM. [ABSTRACT FROM AUTHOR]

By understanding the growth mechanism of nanomaterials, the morphological features of nanostructures can be rationally controlled, thereby achieving the desired physical properties for specific applications. Herein, the growth habits of aluminum nitride (AlN) nanostructures and single crystals synthesized by an ultrahigh-temperature, catalyst-free, physical vapor transport process were investigated by transmission electron microscopy. The detailed structural characterizations strongly suggested that the growth of AlN nanostructures including AlN nanowires and nanohelixes follow a sequential and periodic rotation in the growth direction, which is independent of the size and shape of the material. Based on these experimental observations, an helical growth mechanism that may originate from the coeffect of the polar-surface and dislocation-driven growth is proposed, which offers a new insight into the related growth kinetics of low-dimensional AlN structures and will enable the rational design and synthesis of novel AlN nanostructures. Further, with the increase of temperature, the growth process of AlN grains followed the helical growth model. [ABSTRACT FROM AUTHOR]

The structure evolution and oxidation behavior of ZrB2-SiC composites in air from room temperature to ultrahigh temperature were investigated using furnace testing, arc jet testing, and thermal gravimetric analysis (TGA). The oxide structure changed with the increasing temperature. SiC content has no apparent influence on the evolution of structure during the oxidation of ZrB2-SiC below 1600 °C. However, the evolution of structure for ZrB2-SiC above 1800 °C was significantly affected by the SiC content. The formation of the SiC depleted layer in the ZrB2-SiC system not only depends on the surrounding conditions of pressure and temperature but also on the structure distribution of the SiC in the ZrB2 matrix. The apparent recrystallization of the ZrO2 occurred above 1800 °C. The SiC content should be controlled at ~16% in the ZrB2-SiC system for the ultrahigh-temperature application. The mechanisms of the structure evolution during oxidation in air were also analyzed. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the needed preservation of seeds of Tibetan plants amidst climatic changes.