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Abstract: The Kozak motif, which is located near the translational start codon, often regulates the protein translation. Moreover, it is believed that the conserved positions −3 and +4 contribute the most. Since changes that occur in this motif have a great impact on protein yield and in some cases are associated with disease, we screened the human SNP database for all Kozak-motif-located SNPs (kSNPs) and focused on the strong-changed kSNPs (sckSNPs). Many intron-located and synonymous SNPs are reported to be associated with disease, though the mechanisms underlying these associations are poorly understood. Here, we performed haplotype analysis on sckSNP-containing genes and found that there are some sckSNPs that exist in the same haplotype blocks of reported intron-located and synonymous disease-associated SNPs, indicating that those kSNPs could be a true risk factor for disease-association by affecting the efficiency of protein expression. Our findings provide a candidate explanation for how diseases are associated with intron-located and synonymous SNPs. [Copyright &y& Elsevier]

Abstract: B3LYP and MP2 theoretical methods were employed to study the structures and relative stabilities of the Gly, Ala, Val, Aib, F-Gly, I-Gly and dF-Gly conformers. It was found that the relative stabilities of the Gly, Ala, Val and Aib conformers increase in the same orders of V < IV < III < II < I, due to the similar shapes of the corresponding conformers. Two exceptions exist for the above orders: In Gly, conformer IV is slightly more stable than conformer III; in Aib, conformer II is more stable than conformer I. The relative stability of conformer II vs. I is gradually enhanced by the substitutions of the lateral H atoms with the alkyl groups, especially in the case of the double substitutions to form Aib. The geometries and relative stabilities of the F-Gly, I-Gly and dF-Gly conformers are quite different from Gly as well as Ala, Aib and Val with the alkyl side chains. The driving forces in the conformers of the halogenated amino acids are mainly the intramolecular hydrogen bonding interactions, at least four hydrogen bonds formed in each dF-Gly conformer. For F-Gly and I-Gly, three conformers II–IV exist whereas conformers I and V are spontaneously transformed into conformers IV and III, respectively. It was found that the functional rather than alkyl side chains interact strongly with the NH2CHCOOH fragments and accordingly have more remarkable influences on the geometries and relative stabilities of the conformers. [Copyright &y& Elsevier]

A total of 120 ns molecular dynamics simulations was used to study the folding and conformational aspects of six peptides with different lengths (Pep19–25, Pep15–25, Pep1–25, Pep15–39, Pep1–40, and Pep1–50) truncated from the αβ-tubulin dimer. These truncated peptides were found to undergo distinct structural transitions, with Pep1–25 and Pep1–50 folding into their respective stable conformations whereas on the contrary for the others. All the six truncated peptides are more or less compact than the corresponding segments in the αβ-tubulin dimer. The most striking contraction was observed in Pep1–25, which folds in a similar manner of β-hairpin. Pep1–50 has the least contraction and its folded conformation is the closest to that in the αβ-tubulin dimer. Moreover, the same conversions of β12–β23 from helices to hydrogen-bonded turns were witnessed in both Pep1–50 and the αβ-tubulin dimer. The structural instabilities of Pep19–25, Pep15–25, Pep15–39, and Pep1–40 were caused by the lack of long-distance interactions or/and the absence of key residues, with the details given in the discussions. The folding and conformational divergences of six truncated peptides were also observed in their active peptide segments (Ap15–25). Ap15–25 in Pep1–50 achieves the best agreements with the αβ-tubulin dimer, implying that the local structure of Ap15–25 in the αβ-tubulin dimer can be well reserved in Pep1–50 rather than in the other truncated peptides. The long-distance interactions, especially the key residues (e.g. β48-Arg), play a crucial role in the correct folding of Ap15–25. The correct folding into the stable conformations is a prerequisite for the peptides to implement their catalytic actions, and therefore the present results are helpful to the future designs of active peptides. [ABSTRACT FROM AUTHOR]

Ab initio calculations at MP2 level of theory were used to study the proton transfer at the carboxylic sites of amino acids, in the isolated, mono- and di-hydrated forms. In the case of water dimer, two interaction modes with glycine neutral structures (see Fig. 3) were explored, corresponding to the concerted and stepwise reaction pathways. Their transition states can be described as (H2O&bond;H&bond;OH2)+ [Fig. 4(a)] and (H2O---H&bond;OH2)+ [Fig. 4(b)], respectively. The energy analysis indicated that the concerted pathway is preferred. In the isolated, mono- and di-hydrated glycine complexes, the activation barriers of the proton transfer at the carboxylic sites were calculated to be 34.49, 16.59, and 13.36 kcal mol-1, respectively. It was thus shown that the proton transfer is significantly assisted and catalyzed by water monomer so that it can take place at room temperature. Instead, the further addition of water molecules plays solvent effects rather than catalytic effects to this proton transfer process. The above results obtained with discrete water molecules were supported by the solvent continuum calculated data. It was also observed that the heavy dependence of the solvent continuum models on dipole moments may produce misleading results. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009 [ABSTRACT FROM AUTHOR]

Abstract: A new kind of metal-organic hybrid materials composed of the nickel ions and poly(p-phenylenediamine) have been synthesized in aqueous solution. Long hybrid rods and large nanosheets have been obtained by using the different ratios of the initial reactants. The synthesized rods and nanosheets have been characterized by SEM, TEM, AFM and XPS. The synthesized rods have been found to have porous polymeric structures. The nanosheets are made up of many small nanoparticles. [Copyright &y& Elsevier]

Blue honeysuckle (Lonicera caerulea var. edulis) berry has been used in folk medicine for the treatment of bacterial infections, gastrointestinal disorders, and metabolic diseases. There is evidence to support its pharmacological effects in improving diabetes, fatty liver, and obesity. To investigate the effect of blue honeysuckle berry extract (BHBE) on lipid accumulation in adipocytes and the underlying mechanism. High-performance liquid chromatography (HPLC) coupled with mass spectrometry (MS) was applied to analyze the polyphenolic compounds in BHBE. 3T3-L1 cells were used to induce into adipocytes. Oil Red O staining combined with triglyceride (TG) content determination were carried out to evaluate intracellular lipid accumulation. Western blot was used to determine the expression of lipogenic enzymes and transcription factors. Real-time PCR was used to determine the expression of lipolytic enzymes and adipocyte markers. The primary polyphenols in BHBE are flavonoids (mainly flavonols and anthocyanins). BHBE dose-dependently inhibited lipid accumulation in adipocytes by reducing the expression of fatty acid synthase (FAS) and increasing the phosphorylation level of acetyl-CoA carboxylase (ACC). Moreover, BHBE was found to promote the phosphorylation of AMP-activated protein kinase (AMPK) and further reduce the expression of lipogenic transcription factors (PPARγ, C/EBPα, and SREBP-1c), while the selective AMPK inhibitor attenuated the suppressive effect of BHBE on lipogenesis. In addition, BHBE increased the expression of beige adipocyte markers (Cd137 and Tmem26) and uncoupling protein 1 (UCP1) without affecting the expression of brown adipocyte markers (Ebf3 and Eva1). BHBE inhibits lipid accumulation in adipocytes by suppressing lipogenesis via AMPK activation as well as by promoting beiging of adipocytes, which supports the anti-obesity potential of blue honeysuckle berry. [Display omitted] • Blue honeysuckle berry extract inhibited lipid accumulation in adipocytes. • Blue honeysuckle berry extract suppressed lipogenesis via AMPK activation. • Blue honeysuckle berry extract promoted beiging of adipocytes. [ABSTRACT FROM AUTHOR]

• Cellulose paclitaxel molecularly imprinted polymer (3D-CM&PTX&MIPs) was prepared. • The 3D-CM&PTX&MIPs showed highly adsorption capability for paclitaxel. • 3D-CM&PTX&MIPs has selective recognition ability and reusability. • The 3D-CM&PTX&MIPs can enrich the paclitaxel in Taxus × media Rehde. In this article, we successfully prepared three-dimensional cellulose microspheres modified by molecularly imprinted polymer for paclitaxel recognition and separation (3D-CM &PTX&MIPs). The material was characterized by Fourier Transform Infrared spectroscopy (FTIR), Scanning Electron Microscope (SEM), Thermogravimetric Analysis (TG) and diffraction of X-rays (XRD). Under the optimized adsorption conditions, the maximum adsorption capacity reached 65.7 mg/g. And after 5 runs of reuse, (3D-CM&PTX&MIPs) still maintained a reusability rate of 90%. Besides, (3D-CM&PTX&MIPs) showed excellent selectivity for target PTX. Finally, (3D-CM&PTX&MIPs) was used for PTX recognition and separation in the extracts of yew leaves. This research laid a good foundation and scientific basis for the efficient, environmentally friendly, and rapid enrichment of metabolites in plants using bio-based molecularly imprinted polymers. [ABSTRACT FROM AUTHOR]

[Display omitted] • This paper developed a method for obtaining compounds from disused cili leaves. • The CO 2 -based switchable-solvent is recyclable and environmentally friendly. • The extraction mechanism was studied by density functional theory. • This green extraction and enrichment method was a promising alternative. An efficient and ecofriendly extraction and enrichment process from Rosa roxburghii Tratt leaves using a CO 2 -responsive switchable solvent with ultrasound assistance based on a N,N-dimethyl-cyclohexylamine (DMCHA)/water system was developed in this study. We applied single-factor experiments combined with a Box-Behnken design to obtain the best operation conditions. The optimal parameters were as follows: bubbling CO 2 rate of 40 mL/min, bubbling CO 2 time of 29 min, and ultrasound time of 11.5 min. The yields of representative roxburic acid, kajiichigoside F1, pomonic acid, catechin, epicatechin, kaempferol, rutin, and quercetin reached 1.31 ± 0.02, 1.89 ± 0.01, 1.62 ± 0.02, 0.56 ± 0.015, 1.24 ± 0.024, 0.074 ± 0.002, 0.13 ± 0.001, and 1.56 ± 0.028 mg/g, respectively. The eight phytochemical extraction efficiencies and contents increased observably compared with traditional extraction methods. This process could achieve 5 cycles of extraction without obvious loss. Moreover, the properties of SHS and their relationship with the eight compounds were investigated by density functional theory. This process is a promising alternative for industrial manufacturing. [ABSTRACT FROM AUTHOR]

Abstract: A capillary zone electrophoresis method was developed for fingerprint determination of allantoic fluid in specific pathogen free (SPF) embryonated chicken eggs. The effects of some crucial parameters, such as buffer type, pH, wavelength and running voltage on the separation were studied systematically. The components of the allantoic fluid were well separated using a fused-silica uncoated capillary with an effective length of 50cm and an internal diameter of 50μm. One hundred millimolars sodium tetraborate buffer containing 20mM sodium dihydrogen phosphate with a final pH 9.8 was used as a running buffer. Comparative fingerprints of allantoic fluid in normal and infected with infectious bronchitis virus (IBV) SPF embryonated chicken eggs were also evaluated. The results showed that there were significant differences between composition of normal allantoic fluid and allantoic fluid infected with IBV, which led to different migration behavior. This method was shown to be stable and reproducible with a relative standard deviation of less than 5% for both migration time and peak current. [Copyright &y& Elsevier]

Abstract: In an attempt to improve the antitumor activity and decrease the cytotoxicity of camptothecin, 18 new 10-substituted camptothecin derivatives were prepared. The cytotoxicity in vitro on cancer cell lines and antitumor activity in vivo, and inhibitory properties of topoisomerase I of these derivatives were evaluated. Most of these derivatives possessed lower cytotoxicities than CPT, and the compounds 13, 21, 22, 23, and 24 showed similar topoisomerase I inhibitory activity to CPT. Analogues 13 exhibited the best antitumor activity in vivo among all derivatives we prepared. [Copyright &y& Elsevier]

• Quantitative study on eight components of Acanthopanax senticosus (AS). • Factor analysis (FA) and hierarchical cluster analysis (HCA) process the data. • Qualitative analysis of AS based on fingerprint and similarity analysis (SA). A comprehensive method for the evaluation of Acanthopanax senticosus (AS) was established by the quantitative analysis of multiple components by single marker (QAMS), fingerprint, similarity analysis (SA), hierarchical cluster analysis (HCA), and factor analysis (FA) based on high performance liquid chromatography (HPLC). A total of 27 common peaks were identified in the standard fingerprint of 20 batches of AS from different regions in China, of which 8 peaks were identified as protocatechuic acid, syringin, chlorogenic acid, caffeic acid, eleutheroside E, hyperoside, isofrqxidin, and acacetin, and the concentrations of these eight components were determined simultaneously by QAMS. The results showed that the QAMS method was effective and feasible compared with the external standard method (ESM) (RD < 3.3 %, P ≤ 0.01). Sample 1 (S1) was used as the reference chromatogram, the similarity of other samples was between 0.765 and 0.968. Through HCA, AS could be mainly divided into two production areas, the north Liaoning (including Liaoning) and the south Liaoning areas. Furthermore, FA showed that the quality of AS in the north Liaoning area was better than that in the south Liaoning area. In summary, the method established in this study can comprehensively and systematically evaluate quality differences in AS samples, and may be used to help to improve the quality control of AS. [ABSTRACT FROM AUTHOR]

• A novel magnetic biobased heteropolyacid catalyst was prepared via in-situ reaction. • The conditions of phosphonation and in-situ reaction were optimized. • The catalyst performed efficiently in transesterification of tree-born seed oil. • The catalyst showed excellent stability after recycling for six runs. An active and recyclable magnetic biobased heteropolyacid catalyst (HPW-MCMs) was prepared for the high yield of transesterification of Pistacia chinensis seed oil (PCO). The magnetic cellulose microspheres (MCMs) were used as the supporter, and the phosphotungstic acid (HPW) was synthesized in surface and micropores via in-situ reaction. Fourier transform infrared spectra (FT-IR), scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDX) and diffraction of X-ray (XRD) were fully used to characterize the catalyst. Furthermore, the conditions of 600 W of microwave power, 65 °C of temperature, 6 wt. % of catalyst amount, 8 of methanol/oil ratio and 30 min of reaction time were selected as the optimal conditions. Under the conditions, a high conversion of 96.6 % could be obtained. The HPW-MCMs could also be recovered conveniently and efficiently recycled for six cycles. Therefore, the prepared HPW-MCMs would be potentially useful for the efficient and economic transesterification reaction of PCO. [ABSTRACT FROM AUTHOR]

A novel approach for synchronous extraction and enrichment of hydrophilic component and hydrophobic component with CO 2 -based switchable-solvent (SHS) from pigeon pea leaves was developed in the present study. After screening of SHS, N, N-dimethyl-cyclohexylamine (DMCHA)/water system was selected as the properest SHS for the extraction and enrichment process. To optimize this process, we conducted single factor experiments with the Box-Behnken design. The optimal parameters were as follows: solid-liquid ratio R (S/L) 40:1 (mg/mL), ultrasound time 15 min and bubbling CO 2 time 79 min (0.5 mL/s). Under the circumstances, the extraction yields of representative flavonoid vitexin and stilbene cajaninstilbenes acid (CSA) reached 1.80 ± 0.12 mg/g and 9.32 ± 0.08 mg/g, respectively, which were 1.06 and 1.49 folds to those by the traditional methods. And the contents of target compounds vitexin and CSA in the enriched extracts were 2.3% and 12.1%, which increased above 6.76 and 4.58 folds to that in extracts using 65% ethanol-UAE. And the results suggested that the N, N-dimethyl-cyclohexylamine (DMCHA)/water system can be guaranteed for at least 5 cycles with relatively stable extraction yields of vitexin and CSA. Furthermore, a theoretical study using density functional theory was put into effect to explore the properties of SHS and their relationship with the vitexin and CSA. The mechanism study showed that SHS had higher biocompatibility with target compounds due to the H-bonds. The present method was an eco-friendly, promising, and sustainable alternative to extract and enrich simultaneously hydrophilic and hydrophobic phytochemicals from plant materials. Image 1 • This paper developed a novel approach for efficient and recyclable extraction and enrichment of phytochemicals from the disused pigeon pea leaves in one solvent system. • The mechanism study showed that SHS had higher biocompatibility with target compounds due to the H-bonds using the density functional theory. • The switchable solvents have usually been used in the extraction of oil. Moreover, the exploit of SHS considering bioactive compounds from plants material has hardly been reported yet. [ABSTRACT FROM AUTHOR]

• A new ZnS quantum dot-based MIP is developed for specific recognition of paclitaxel. • The addition of M-POSS significantly improves the pore structure of POSS-MIP/QDs. • POSS-MIP/QDs have uniform spherical shapes and excellent dispersibility in solution. • The obtained POSS-MIP/QDs shows fast detection ability and reusability. In this study, a molecularly imprinted fluorescent sensor was constructed successfully for selective recognition of PTX by introducing methacryl polyhedral oligomeric silsesquioxane (M-POSS) to add porous structure. The obtained fluorescent sensors were prepared by grafting MIP shell on the surface of silane functionalized Mn: ZnS Quantum Dots (QDs) by a free radical polymerization process. The binding properties and selectivity of the MIP-QDs were demonstrated by adsorption capacity obtained based on fluorescence spectroscopy. These MIP-based fluorescent sensors showed good dispersibility and high stability in solution. Under the optimized conditions, the binding experiment demonstrated the fluorescent intensity of the porous fluorescent sensors was obviously decreased with the increase of PTX in the concentration range 0.1–2.0 μM and the detection limit was 0.043 μM. These results demonstrated a new type of molecularly imprinted fluorescent porous nanoparticles with potential applications for selective recognition of PTX biological samples. [ABSTRACT FROM AUTHOR]

• Modified porous cellulose microspheres (p-CM@MPS) were prepared successfully. • A Res molecularly imprinted polymer was prepared using p-CM@MPS as the carrier. • The p-CM@MPS@MIP-Res showed remarkable adsorption capacity and reusability. • The p-CM@MPS@MIP-Res was used as an adsorbent for resveratrol enrichment. A novel resveratrol molecularly imprinted polymer (p-CM@MPS@MIP-Res) was prepared on the surface of silanized porous cellulose microspheres (p-CM@MPS) for the first time, and was successfully applied for the efficient enrichment of targeted resveratrol in Polygonum cuspidatum. The adsorption kinetics and adsorption equilibrium of p-CM@MPS@MIP-Res were also studied in detail. Compared with non-molecularly imprinted polymer (p-CM@MPS@NIP), the prepared p-CM@MPS@MIP-Res showed high adsorption capacity for resveratrol, the adsorption capacity of the p-CM@MPS@MIP-Res could reach to 11.56 mg/g. Furthermore, the stability of the p-CM@MPS@MIP-Res was evaluated and the result showed that the p-CM@MPS@MIP-Res could be reused for 5 runs. Finally, the p-CM@MPS@MIP-Res was applied to enrich the resveratrol in Polygonum cuspidatum sample, the content of resveratrol in the extraction solution could be increased greatly from 4.23 % to 23.74 %, indicating the p-CM@MPS@MIP-Res was a promising adsorbent for efficiently separation and enrichment of resveratrol in Polygonum cuspidatum. [ABSTRACT FROM AUTHOR]

• A green one-pot method for simultaneous extraction and transesterification of seed oil was proposed. • Novel p -toluenesulfonic acid based deep eutectic solvents were prepared successfully. • Central composite design (CCD) and response surface methodology were conducted. • High extraction and transesterification yields of oil demonstrated the eff ;ectiveness of the prepared catalyst. In this study, a novel p -toluenesulfonic acid (PTSA) based deep eutectic solvent (DES) was prepared successfully for biodiesel production by one-pot method. The DES consisting of PTSA and tetrabutylammonium bromide (TBAB) exhibited the best catalytic activity among the five prepared DESs. Central composite design (CCD) and response surface methodology were conducted to investigate reaction factors. The maximum oil extraction yield 90.33 % and fatty acid methyl esters (FAMEs) conversion yield 96.53 % were obtained under the optimal condition: microwave temperature 72 °C, microwave power 500 W, time 40 min, the ratio of liquid to seed weight 27:1 and DES amount 11 wt%. The chemical composition of FAMEs and main physical-chemical properties were investigated and the results demonstrated that the prepared biodiesel product possessed high quality. The study showed the prepared DES was a green and efficient catalyst for rapid and simultaneous extraction and transesterification seed oil for biodiesel production by one-pot method. [ABSTRACT FROM AUTHOR]

• Proanthocyanidins-Fe 3 O 4 nanoparticles were synthesized by a hydrothermal method. • The Fe 3 O 4 nanoparticles have been characterized by FTIR, SEM, TEM and XRD. • The Fe 3 O 4 nanoparticles can efficiently removal of heavy metal ions. Large-scale hydrophilic proanthocyanidins-functionalized Fe 3 O 4 nanoparticles were synthesized via a hydrothermal approach. The obtained Fe 3 O 4 nanocomposites were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). The results revealed that the Fe 3 O 4 nanoparticles had cubic spinel structure and capped by proanthocyanidins outside. Furthermore, the proanthocyanidins-functionalized Fe 3 O 4 nanoparticles can be utilized to adsorb the heavy metal ions in water. The primary results indicated that the proanthocyanidins-functionalized Fe 3 O 4 nanoparticles have high removal rate for Cu2+, Cd2+ and Pb2+ in water. [ABSTRACT FROM AUTHOR]

Sulfur compounds in oil phase were captured into the catalyst phase, then oxidized to their corresponding sulfones in the presence of molecular oxygen. • A series of electrophilicity-tunable ionic liquids were successfully synthesized via a facile ion exchange method. • Both cation and anion parts in ionic liquid played an important role in ODS process. • The prepared ionic liquid [C 4 VIM]PMoV 2 exhibited high efficiency in aerobic ODS process under mild conditions. • The structure-function relationship was investigated in detail from various methods. With increasing stringent standard of sulfur content in fuels, deep desulfurization with high-efficiency is necessary for ecological and environmental demands. Herein, vanadium-substituted polyoxometalate-based ionic liquids with tunable electrophilicity were facilely synthesized through ion exchange method, and applied in the aerobic oxidative desulfurization. The experimental results indicated that both imidazole cation and polyoxometalate anion played a vital role in the desulfurization process. The prepared materials have a good performance on the degradation of aromatic sulfur compounds, which can reach up to 98.9 % under optimal conditions. Moreover, the structure-function relationship was also investigated in detail, as well as the proposed mechanism. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this study was to evaluate the in vitro and in vivo antitumor efficacy and the dose dependent toxicity of camptothecin nanosuspension (Nano-CPT) comparing with that of topotecan (TPT). A novel supercritical antisolvent (SAS) process-high pressure homogenization technique has been developed to prepare Nano-CPT. The cytotoxicity of Nano-CPT and TPT was investigated against MCF-7, HCT-8, and PC-3 cell lines using MTT assay, antitumor activity in vivo were evaluated against HCT-8 xenograft model, and the dose dependent toxicity in vivo during the treatment were investigated by body weight changes and relative organ weight variations. The Nano-CPT presents about 6 times in vitro cytotoxicity active than TPT against cell lines MCF-7, nearly the same in vivo antitumor activity with TPT and lower toxicity. The results confirm that Nano-CPT is a novel potential formulation with high antitumor efficacy and low toxicity. [Copyright &y& Elsevier]

• Uniform porous PTX-MIP microparticles were prepared by RAFTPP. • The amounts of M−POSS significantly improved the pore structure of PTX-MIP. • The PTX-MIP exhibited good adsorption selectivity towards Paclitaxel. • The obtained PTX-MIP showed fast adsorption kinetics and reusability. A type of novel porous molecularly imprinted polymer (MIP) microspheres containing methacryl polyhedral oligomeric silsesquioxane (M−POSS) were synthesized through reversible addition-fragmentation chain transfer polymerization precipitation polymerization (RAFTPP). The obtained porous microspheres had narrow particle size distribution and regular spherical shape. The addition of M−POSS could not only largely enhance the structural stability but also increase the pore structure of MIPs. The composition and shape characteristic of the MIPs were characterized by FT-IR, CA, SEM, TGA, and N 2 adsorption–desorption isotherm. The binding properties and selectivity of the MIP and non-imprinted polymer (NIP) were demonstrated by adsorption capacity obtained based on HPLC absorption measurements. The results showed that the adsorption capacity of the paclitaxel imprinted polymer containing 85 mg M−POSS (PTX-MIP2) for PTX reached 17.24 mg g−1 after 200 min. A comparative study demonstrated that PTX-MIP2 possessed excellent selectivity towards PTX, which presented an imprinting factor of 3.17. Meanwhile, PTX-MIP2 could be reused five cycles with slight loss in adsorption capacity. [ABSTRACT FROM AUTHOR]