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The 2-layer medium has a semitransparent diffuse interface and four black surfaces. The fully implicit finite difference method is used to discretize the 2-D transient differential heat transfer equation, in which a radiative source term is considered. The radiative source term is expressed by radiative transfer coefficients, which are solved by establishing functions to trace the reflection and transmission of radiative energy. By using the Patankar linearization method, additional source term method, and alternating direction implicit method, temperature distribution within the 2-layer medium is solved. The increase in the refractive indexes of the 2-layer medium makes the temperature distribution of the composite more uniform and the time to reach a steady state to be reduced. Compared with pure radiation, the participation of conduction makes the heat transfer ability of the 2-layer medium to be enhanced and the temperature distribution discontinuity at the interface disappears. [ABSTRACT FROM AUTHOR]

Oil Red O (ORO) staining is a commonly used experimental technique to detect lipid content in cells or tissues. Freshly prepared ORO in 60% isopropanol is the most widely used method at present. However, isopropanol is volatile and harmful to the human body. It will also affect the interpretation of the results due to the formation of crystals and non-specific diffuse staining. In this paper, by screening and validation, we report a salicylic acid ethanol solution (containing 50% ethanol, 5%-10% salicylic acid) for the preparation of ORO solution, which has a better staining effect on lipid staining in cells and tissues, with a clean background and short dyeing time. What's more, this ORO solution is non-toxic, convenient to prepare, and can be stored for a long time. Therefore, it is reliable, easy to operate, and can be widely popularized and applied in laboratories. [ABSTRACT FROM AUTHOR]

Cerebral ischemia/reperfusion (I/R) injury is a brain injury following ischaemic stroke that is associated with oxidative stress. Taraxasterol, a natural product, has been shown to have anti-oxidative and neuro-protective effects. However, the role of taraxasterol in cerebral I/R injury remains unknown. Primary hippocampal neurons were subjected to oxygen-glucose deprivation/reperfusion (OGD/R) to induce cerebral I/R injury in vitro. Cell viability of hippocampal neurons was measured CCK-8 assay. Reactive oxygen species (ROS) production and MDA generation were measured to reflect oxidative stress. Western blotting was performed to evaluate the expressions of bax, bcl-2, NF-E2-related factor 2 (Nrf2), haem oxygenase (HO-1), NAD(P)H:quinone oxidoreductase 1 (NQO-1) and GPx-3. Caspase-3 activity was measured to assess cell apoptosis. Hippocampal neurons were treated with ML385 to inhibit Nrf2 signalling pathway. Our results showed that taraxasterol improved OGD/R-caused decrease in cell viability of hippocampal neurons. In addition, taraxasterol significantly suppressed ROS production and MDA generation in OGD/R-induced hippocampal neurons. Taraxasterol resulted in a significant decrease in caspase-3 activity and bcl-2 expression, as well as increase in bax expression. Furthermore, taraxasterol induced the Nrf2 nuclear accumulation and expressions of HO-1, NQO-1 and GPx-3 in OGD/R-induced hippocampal neurons. Notably, inhibition of Nrf2 signalling reversed the protective effects of taraxasterol on OGD/R-induced hippocampal neurons injury. In conclusion, these findings indicated that taraxasterol protected hippocampal neurons from OGD/R-induced oxidative stress and cell apoptosis via regulating the Nrf2 signalling pathway. [ABSTRACT FROM AUTHOR]

The development of novel magnetic nanoparticles (MNPs) with satisfactory biocompatibility for biomedical applications has been the subject of extensive exploration over the past two decades. In this work, we synthesized superparamagnetic iron oxide MNPs coated with polystyrene sulfonic acid (PSS-MNPs) and with a conventional co-precipitation method. The core size and hydrodynamic diameter of the PSS-MNPs were determined as 8–18 nm and 50–200 nm with a transmission electron microscopy and dynamic light scattering, respectively. The saturation magnetization of the particles was measured as 60 emu g−1 with a superconducting quantum-interference-device magnetometer. The PSS content in the PSS-MNPs was 17% of the entire PSS-MNPs according to thermogravimetric analysis. Fourier-transform infrared spectra were recorded to detect the presence of SO3− groups, which confirmed a successful PSS coating. The structural properties of the PSS-MNPs, including the crystalline lattice, composition and phases, were characterized with an X-ray powder diffractometer and 3D nanometer-scale Raman microspectrometer. MTT assay and Prussian-blue staining showed that, although PSS-MNPs caused no cytotoxicity in both NIH-3T3 mouse fibroblasts and SK-HEP1 human liver-cancer cells up to 1000 μg mL−1, SK-HEP1 cells exhibited significantly greater uptake of PSS-MNPs than NIH-3T3 cells. The low cytotoxicity and high biocompatibility of PSS-MNPs in human cancer cells demonstrated in the present work might have prospective applications for drug delivery. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the effects of astragalus polysaccharides (APS) on the proliferation and apoptosis of bone marrow mesenchymal stem cells (BMSCs) induced by X-ray radiation-induced A549 cells bystander effect (RIBE), and to explore their mechanisms. In this study, APS increased the reduced cell proliferation rate induced by RIBE and inhibiting the apoptosis of bystander cells. In terms of mechanism, APS up-regulates the proteins Bcl-2, Bcl-xl, and down-regulates the proteins Bax and Bak, which induces a decrease in mitochondrial membrane potential, which induces the release of Cyt-c and AIF, which leads to caspase-dependent and caspase-independent pathway to cause apoptosis. In addition, we believe that ROS may be the main cause of these protein changes. APS can inhibit the generation of ROS in bystander cells and thus inhibit the activation of the mitochondrial pathway, further preventing cellular damage caused by RIBE. [ABSTRACT FROM AUTHOR]

The sensitivity of myocardium is enhanced to ischemia/reperfusion (I/R) injury under PM2.5 exposure. It is still under prelude for lncRNA-miRNA pair in the study of aggravated myocardial I/R injury under PM2.5 exposure. In this study, we first built a rat model of 30 min ischemia and 24 h reperfusion followed PM2.5 (6.0 mg/kg) exposure. We found PM2.5 exposure could obviously aggravate I/R injury in the fields of myocardium damage, apoptosis levels and cardiac function which were evaluated by TTC staining, TUNEL and echocardiography, respectively. Then, based on results of sequencing and RT-qPCR, we selected NONRATT003473.2 in the follow-up experiments and named this lncRNA as PM2.5 exposure aggravated myocardial I/R injury lncRNA (PEAMIR). Consistent with the results rat model, we confirmed PEAMIR to be a protective lncRNA against PM + HR triggered damages in H9c2 cells. Next, according to the bioinformatics analysis from miRanda database and a series of gain- and loss-of-function experiments, we proved PEAMIR to be a ceRNA for miR-29b-3p to inhibit cardiac inflammation and apoptosis. Finally, using Target-Scan database, the conserved binding sites for miR-29b-3p was identified in the 3'UTR of PI3K (p85a), a key protein of apoptosis. Our subsequent experiments validated the regulatory relationship between PEAMIR-miR-29b-3p ceRNA pair and PI3K (p85a)/Akt/GSK3b/p53 cascade pathway. In conclusion, our study demonstrated the role and mechanism of PEAMIR in the augment of I/R injury under PM2.5 exposure, suggesting a promising strategy for the prevention and treatment of I/R injury under PM2.5 exposure. [ABSTRACT FROM AUTHOR]

The ~100,000 km2 granitoid belt in the Lesser Xing'an-Zhangguangcai Ranges (LXZR) is an important component of the Phanerozoic granitic provinces (known as the 'granitoid ocean') in NE China. To reveal the mechanisms of Mesozoic magmatism and crustal growth in the LXZR, we present systematic geologic data, lithofacies information, zircon U-Pb ages, Hf isotopic, and element geochemical data for the Dong'an granites in the northern LXZR. The results show the following: (1) the Dong'an granites can be subdivided into three lithofacies, namely, medium- to coarse-grained alkali-feldspar granite, fine-grained alkali-feldspar granite, and granitic aplite, which were emplaced during the Early Jurassic (187–178 Ma); (2) the Dong'an granites are characterized by high SiO2 and total alkali contents and low Fe2O3t contents and Mg# values, and they are enriched in LILEs (e.g., Rb and K) and depleted in HFSEs (e.g., Nb and Ta); and (3) the zircons from these granites yield εHf(t) values of −2.4 to +5.7 and two-stage model ages of 772–1542 Ma. These results indicate that the Dong'an granites were emplaced during the Early Jurassic, are highly fractionated I-type (HFI) granites and were likely derived from partial melting of the thickened lower crust. Regionally, the Dong'an granites and the Early-Middle Jurassic intrusive rocks (201–163 Ma; 90,000 km2) in the LXZR show a trend of comagmatic evolution controlled by fractional crystallization, and they were successively emplaced during magma evolution. The HFI granites that are geochemically similar to the Dong'an granites formed in the later stage of magma evolution. Combined with regional geological observations, we conclude that the granitic rocks in the LXZR formed in an active continental margin setting related to the subduction of the Paleo-Pacific Plate beneath the Eurasian continent. This process may record an important episode of crustal accretion in the LXZR. [ABSTRACT FROM AUTHOR]

Backgrounds and aims: Increased arterial stiffness may increase cardiovascular morbidity and mortality. Angiotensin II type 1 receptor blockers (ARBs) are potentially useful in controlling the central blood pressure and arterial stiffness in mild to moderate essential hypertension, while the effects of ARBs in aged patients with essential hypertension are not entirely investigated. Methods: The carotid-femoral arterial pulse wave velocity (PWV) was measured in aged patients with essential hypertension. Results: In a cross-sectional study, PWV value was significantly higher in these old patients with essential hypertension, compared to patients without essential hypertension. In correlation analysis, PWV was associated positively with age, hypertension duration, and carotid atherosclerosis. However, there was no relationship between PWV and gender in aged patients with essential hypertension. In a perspective study, 6–12 months administration of ARBs (losartan, 50 mg/day; telmisartan, 40 mg/day; valsartan 80 mg/day; irbesartan, 150 mg/day) remarkably reduced PWV in aged patients with essential hypertension. Regression analyses of multiple factors indicated that the effects of ARBs on arterial stiffness were not associated with the reduction of blood pressure. Conclusion: ARB treatment is a negative risk factor of arterial stiffness in aged patients with essential hypertension. [ABSTRACT FROM AUTHOR]

An energy-based method for thermal stresses of various statically indeterminate structures is presented. Using the Lagrange multiplier method, internal forces of statically indeterminate structures are investigated. A new functional from unconditional generalized variational principles is presented. Based on the variational method, a general matrix solution for internal forces and thermal stresses of statically indeterminate structures is established. Several types of structures including the rivet, truss, and bilayer cantilever beam are considered. Compared with the traditional methods, the accuracy and universality of the present model are confirmed. This work provides a convenient and unified method to solve the thermal stresses of various statically indeterminate structures. [ABSTRACT FROM AUTHOR]

This study combines finite element method and animal studies, aiming to investigate tissue remodelling processes around dental implants inserted into sika deer antler and to develop an alternative animal consuming model for studying bone remodelling around implants. Implants were inserted in the antlers and loaded immediately via a self-developed loading device. After 3, 4, 5 and 6 weeks, implants and surrounding tissue were taken out. Specimens were scanned by μCT scanner and finite element models were generated. Immediate loading and osseointegration conditions were simulated at the implant-tissue interface. A vertical force of 10 N was applied on the implant. During the healing time, density and Young’s modulus of antler tissue around the implant increased significantly. For each time point, the values of displacement, stresses and strains in the osseointegration model were lower than those of the immediate loading model. As the healing time increased, the displacement of implants was reduced. The 3-week immediate loading model (9878 ± 1965 μstrain) illustrated the highest strains in the antler tissue. Antler tissue showed similar biomechanical properties as human bone in investigating the bone remodelling around implants, therefore the use of sika deer antler model is a promising alternative in implant biomechanical studies. [ABSTRACT FROM AUTHOR]

Glycopolymers with different sugar densities were prepared by reacting monomericS-sialoside with polymers carrying maleic anhydride moieties. The glycoconjugates as mucin mimics competitively inhibit viral infection through multivalent interactions with hemagluttinin and neuraminidase as sialic acid receptor, which were evaluated using hemagglutination aggregation, neuraminidase inhibition assays and isothermal titration calorimetry. These glycopolymers can also be potentially used as capture molecules for a wide variety of viral strains. We anticipate that theseS-sialyl polymers with strong bindings to influenza virus can not only be used as antiviral agents but also tools for the study of sialic acid-influenza virus recognition, interaction and capture. [ABSTRACT FROM PUBLISHER]

A multivalent Zanamivir (ZA) conjugate as new anti-influenza agent was prepared. Specifically, multiple copies of ZA with a C7 azido-terminated linker were covalently attached onto alkyne-modified bovine serum albumin (BSA)viacopper-free click reaction. The loading number of ZA was determined by MALDI-TOF. Primary neuraminidase (NA) inhibition assay showed that this conjugate retained some NA inhibitory activity compared to its parent ZA monomer. Moreover, the ZA-BSA conjugate was not cytotoxic with concentrations up to 1 µM. [ABSTRACT FROM PUBLISHER]

Studies demonstrated that deficiency in 17β-estradiol (E2) in postmenopausal women influences their immune system. However, few studies have reported alterations in immunologic presentation during nonnatural menopause in young females. Here we compared the differences in immune response between young C57BL/6N mice with surgical or medical variectomy and aged C57BL/6N mice with the common feature of E2deficiency following Con A stimulation. We observed inverted CD4/CD8 ratios in the aged group and apparent reduced production of serum immunoglobin (Ig)G, IgA, and IgM in the surgical group, whereas changes in immune parameters in the medical group were moderate. These data suggested that the immunological response to Con A stimulus differed among the three groups and that E2deficiency was only partially responsible for the development of immune deficiency in aged mice. [ABSTRACT FROM PUBLISHER]

Four coordination polymers, [CsL1(H2O)2]·H2O (1), [CsL2(H2O)2]·H2O (2), [Rb2(L2)2(H2O)2]·2H2O (3) and [RbL3(H2O)] (4), were synthesized by Cs(I), Rb(I) and 4′-hydroxyisoflavone-3′-sulfonatesL1–L3[L1 = 7-methoxy-4′-hydroxyisoflavone-3′-sulfonate,L2 = 7-ethoxy-4′-hydroxyisoflavone-3′-sulfonate,L3 = 7-ethoxy-4′,5-dihydroxyisoflavone-3′-sulfonate]. The crystal structures of1–4were determined by single-crystal X-ray diffraction. The influences of 4′-hydroxyisoflavone-3′-sulfonate ligands and Cs+, Rb+on their structural features and self-assembly were investigated. The sulfonates ofL1–L3not only coordinate with Cs+or Rb+directly, but also bridge the organic region and the inorganic region in1–4. Non-covalent interactions such as coordination interaction,π–πstacking interaction and hydrogen bonding assembled1–4into 3-D networks together with the electrostatic interactions between Cs+, Rb+and the sulfonate anions. [ABSTRACT FROM PUBLISHER]

To characterize the ultraphytoplankton community structure and understand its succession, we investigated photosynthetic pigment concentration and composition; algae phyla composition and abundance; and environmental factors in Xiangxi Bay (XXB) from February to December 2013. High-performance liquid chromatography (HPLC) analyses revealed eight diagnostic pigments: Fucoxanthin, Neoxanthin, Violaxanthin, Alloxanthin, Lutein, Zeaxanthin, Chlorophyll b and Chlorophyll a. The temporal differences between seven of the pigments (all excepting Neoxanthin) were significant (P< 0.05), and there were no significant spatial differences between the eight pigments (P> 0.05). A chemical taxonomy (CHEMTAX) calculation identified seven phyla of ultraphytoplankton: cryptophytes, chlorophytes, cyanobacteria, diatoms, euglenophytes, chrysophytes, and dinoflagellates. The temporal differences between five of the phyla (except chlorophytes and euglenophytes) were significant (P< 0.05), and there was no significant spatial difference between the seven phyla (P> 0.05). The redundancy analyses demonstrated that the key environmental factors for the succession were N-NH4+and P-PO43–. Application of the HPLC-CHEMTAX method has provided the first analysis of ultraphytoplankton community structure in XXB, and our findings also show that environmental factors influence the succession of ultraphytoplankton over time. [ABSTRACT FROM PUBLISHER]

A simple, rapid, and sensitive electrochemical aptasensor based on target-induced strand displacement and gold nanoparticle amplification was developed for the determination ofSalmonella. The aptamer forSalmonellawas captured on the sensing interface by hybridizing with a capture probe. In the presence ofSalmonella, the aptamer dissociated from the capture probe as the stronger interaction between the aptamer and theSalmonella. The single-strand capture probe was then hybridized with the biotinylated detection probe assembled on gold nanoparticles and catalyzed by streptavidin–alkaline phosphatase, providing a sensitive electrochemical response. The gold nanoparticles significantly amplified the detection probe signal and increased the sensitivity. The linear dynamic range was from 2 × 101to 2 × 106CFU mL−1with a detection limit of 20 CFU mL−1. This strategy was utilized for the determination ofSalmonellain milk, demonstrating potential application in clinical diagnostics, food safety, and environmental monitoring. [ABSTRACT FROM AUTHOR]

The role ofHelicobacter pylori(H. pylori) infection on thrombocytopenia in chronic hepatitis B (CHB) related compensatory cirrhotic patients is unknown. We conducted an observational study to determine whetherH. pyloriplays a role in these patients. A total of 255 patients from three centers in China were enrolled in the study. All patients received nucleoside analogs (NA) therapy and were screened forH. pyloriinfection. Patients were divided into three groups based on theirH. pyloriinfection status and the therapy administered: patients withoutH. pyloriinfection who received NA therapy alone (N = 146); patients withH. pyloriinfection who received NA therapy alone (n = 48); and patients withH. pyloriinfection who receivedH. pylorieradication combined with NA therapy (N = 61). We observed that in CHB compensatory cirrhotic patients withH. pyloriinfection, the platelets count was significantly lower relative to uninfected patients (31 versus 60 × 109/L,p < 0.01). During a 2-year follow-up, the elevation in platelet count was significantly higher in HBV/H. pylorico-infected patients who received the NA andH. pylorieradication treatment compared to the other two groups (p < 0.01). It suggested thatH. pyloriinfection and eradication treatment combined with NA were independent risk factors associated with platelets response during treatment of thrombocytopenia in CHB compensatory cirrhosis (p < 0.01). In conclusion,H. pyloriinfection may associate with thrombocytopenia in CHB compensatory cirrhosis.H. pylorieradication combined with NA treatment may prove to be beneficial to CHB compensatory cirrhotic patients with thrombocytopenia who are infected withH. pylori. [ABSTRACT FROM PUBLISHER]

In the presence of iron dust, diaryl disulfides react withα-bromo carbonyl compounds to obtainα-arylthio carbonyl compounds in good yield at 90 °C under an N2atmosphere, using commercial dimethylformamide (DMF) as solvent. The possible reaction mechanism is that the disulfide is reduced by iron dust to give ArSFeSAr and then reacted withα-bromo carbonyl compounds to give productα-arylthio carbonyl compounds and FeBr2. [ABSTRACT FROM PUBLISHER]

This study focuses on the correlations between the structural dynamic properties and the instantaneous response characteristics of a 492-m high building during a typhoon. An instantaneous analysis framework is established based on a combined usage of both linear-phase filtering and time–frequency techniques. This analysis framework can separate each modal response contribution without phase distortions. Random decrement technique is used to estimate the modal damping ratios. It is found that beating phenomenon widely exists in the separated modal response contributions, and the damping ratios correlate with the modulation of phase and amplitude within the beating closely. When the beating amplitude comes close to zero, the instantaneous frequency fluctuates evidently. The more intensive this fluctuation is, the larger the damping ratio becomes. An empirical model is presented to formulate the variations of damping ratio and natural frequency of this building with the fluctuation intensity of the instantaneous frequency. [ABSTRACT FROM AUTHOR]

This article presents a high-frequency method for the prediction of radar cross-section of coated targets with extremely electrically large size in the terahertz band in free space. To consider the scattering characteristics of the coated targets with a rough surface in the terahertz band, taking into account the effect of surface roughness, the reflection coefficients on the smooth coating surface can be modified; the equivalent electric and magnetic currents on the surface can then be corrected by the modified reflection coefficients to obtain the electric and magnetic induced current densities on the rough coating surface. Therefore the physical optics method, which was combined with the graphical electromagnetic computing method and improved using the partition display algorithm, can be used to solve the scattered fields, and the radar cross-section of the coated targets with a rough surface in the terahertz band can then be obtained. Numerical results for several coated targets, such as the mother warhead of the Minuteman III intercontinental ballistic missile and VFY-218 aircraft, are given and discussed. The results provide an important basis and method for applications of terahertz radar in many fields, such as military, astronomy, and remote sensing, in the future. [ABSTRACT FROM AUTHOR]

Mitomycin C (MTC) was incorporated to a micelle system preparing from a polymer named deoxycholic acid chitosan-grafted poly(ethylene glycol) methyl ether (mPEG-CS-DA). mPEG-CS-DA was synthesized and characterized by 1H nuclear magnetic resonance (1H-NMR) and Fourier transform infrared spectroscopy. mPEG-CS-DA formed a core-shell micellar structure with a critical micelle concentration of 6.57 µg/mL. The mPEG-CS-DA micelles were spherical with a hydrodynamic diameter of about 231 nm. After poly(ethylene glycol)ylation of deoxycholic acid chitosan (CS-DA), the encapsulation efficiency and drug loading efficiency increased from 50.62% to 56.42% and from 20.51% to 24.13%, respectively. The mPEG-CS-DA micelles possessed a higher drug release rate than the CS-DA micelles. For pharmacokinetics, the area under the curve (AUC) of the mPEG-CS-DA micelles was 1.5 times higher than that of MTC injection, and these micelles can enhance the bioavailability of MTC. mPEG-CS-DA micelles reduced the distribution of MTC in almost all normal tissues and had the potential to improve the kidney toxicity caused by MTC injection. [ABSTRACT FROM AUTHOR]

In 2003, the Chinese Government initiated a free antiretroviral therapy (ART) program focusing on adult AIDS patients. Pediatric antiretroviral (ARV) formulations were yet unavailable. It was not until July 2005, with the initiation of a two-stage program implemented by the Chinese Ministry of Health, that pediatric formulations became accessible in China. Initially, the pediatric ART program was piloted in six provinces with the highest incidences of pediatric HIV/AIDS. The pilot stage allowed the Chinese Center for Disease Control and Prevention (CCDC) to finalize entry criteria, treatment regimen, and patient monitoring and follow-up procedures. The second stage commenced at the end of 2006 when the program was scaled-up nationally. In order to guarantee treatment of pediatric patients, extensive training in the selection of appropriate ARV drug regimen and dosage was provided to doctors, often through on-site collaboration with domestic and international experts. The CCDC simultaneously established a pediatric ARV management system and a pediatric ART information system. CD4 count and other laboratory tests are being routinely performed on these pediatric patients. By the end of June 2009, 1529 pediatric patients had received ARV under the national program. However, challenges remain. Firstly, many children infected with HIV/AIDS live in rural areas where the treatment quality is hindered by the limited number of medical facilities and skilled medical workers. Secondly, much of the pediatric ARV drug supply depends on donation. An effort needs to be made by the Chinese Government to establish China's own drug procurement and supply system. [ABSTRACT FROM AUTHOR]

Background and objectives: The Kidd system antibodies, if undetected, can cause immediate or delayed hemolytic transfusion reactions as well as hemolytic disease of the newborn. There have been anecdotal reports about the inefficiency of the manual Polybrene test in detecting these antibodies. Here, we sought to determine the sensitivity of the manual Polybrene test in detecting anti-Jka and anti-Jkb antibodies and Jka and Jkb antigens. Materials and methods: Ten archived anti-Jka/Jkb antibody positive human sera were examined by both the manual Polybrene test and the indirect antiglobulin test using polyspecific antibodies, monospecific anti-IgG antibodies and anti-C3 antibodies. Furthermore, 40 randomly selected donor blood samples were collected and phenotyped for the frequencies of Jka and Jkb antigens using the manual Polybrene test and the indirect antiglobulin test. The results from these tests were further confirmed by saline tube tests. Results: The manual Polybrene test displayed an overall sensitivity of 60% in detecting anti-Jka and anti-Jkb antibody. Specifically, it had a sensitivity of 57.14% for anti-Jka antibody and a sensitivity of 66.7% for anti-Jkb antibody. Furthermore, the manual Polybrene test exhibited a sensitivity of 46.15% for Jka antigen and a sensitivity of 77.42% for Jkb antigen. Conclusion: The manual Polybrene test has a very low sensitivity in detecting anti-Jka and anti-Jkb antibody, especially anti-Jka antibody. It is also a very insensitive test for detecting Jka antigen. [ABSTRACT FROM AUTHOR]