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The expanded forehead flap has its unique advantage in nasal reconstruction. The authors present their 12-year experience with nasal reconstruction with an expanded forehead flap. The esthetic and functional outcomes were assessed with long-term subjective and objective evaluations. A retrospective analysis was conducted of consecutive patients who underwent nasal reconstruction with the expanded forehead flap from 2009 to 2021 performed by the senior author (F.F.). Data were collected and analyzed regarding defect characteristics, processes of treatment, and complications. Subjective esthetic and functional outcomes were assessed through questionnaires FACE-Q (Face Questionnaire) and NOSE (Nasal Obstruction Symptom Evaluation). The objective esthetic outcome was assessed by a senior resident through the viewing of clinical photographs. One hundred and fifty-five patients underwent nasal reconstruction with an expanded forehead flap. The average expansion period was 174 days, and the injection volume was 685.7 ml. There were 15 complications. One hundred and eight patients (69.6%) were satisfied, and 19 patients (12.2%) were very satisfied with the outcome. The differences between postoperative and preoperative scores of FACE-Q were statistically significant (p < 0.01). Sixty-nine percent of patients complained of bilateral eyebrow asymmetry, 27.1% of patients reported partial recovery of frontal deformity with dissatisfaction, and 2.6% of patients considered not recovered at all. The results of 78 patients (50.3%) were considered "satisfied," and 41 patients (26.5%) were considered "very satisfied" by objective evaluation. Nasal reconstruction with an expanded forehead flap was a safe technique with good esthetic outcomes. Although problems with the asymmetry of the eyebrows and frontal deformation were presented, the influence was minimal and well-accepted by most patients. [ABSTRACT FROM AUTHOR]

The zinc smelting solution purification process regulates the oxidation-reduction reactions (characterized by the oxidation-reduction potential (ORP)) by controlling the amount of zinc powder added to remove the impurity ions. In order to ensure the optimal operation of the process, the target key technical indicators should be converted into the optimal setpoint of controlled variables (that is, ORP). Based on the mechanism knowledge, fuzzy rules, and preference-guided predictive optimization, a comprehensive setting method for the optimal setpoint of controlled variables under multi-variation inlet status is proposed. It includes a hybrid trend detection method for inlet status, a mechanism model under multiple operating modes, and a fuzzy correction method and a preference-guided predictive optimization method to deal with slight and violent fluctuations in the inlet status, respectively. The experimental results show that the proposed method can obtain the optimal setpoint of controlled variables and reduce zinc powder consumption by approximately 3.6%. • A comprehensive setting method for the optimal setpoint of controlled variables under multi-variation status is proposed. • A hybrid trend detection method is proposed to identify different inlet statuses of the solution purification process. • Based on the reaction kinetics and the reaction efficiency, a mechanism model under multiple operating modes is constructed. • An optimal setpoint correction method based on fuzzy rules is proposed to cope with slight changes in inlet status. • A preference-guided predictive optimization method is proposed to cope with violent changes or anomalies in inlet status. [ABSTRACT FROM AUTHOR]

The solution purification process includes multiple continuous reactors. Setting the key technical indicators of each reactor through global optimization is the prerequisite for realizing the optimal operation of the entire process. Affected by fluctuations in inlet conditions, adjustments of operating parameters, and random disturbances, the operating status of the solution purification process will change accordingly, causing the optimal value settings based on global optimization to become no longer applicable. To ensure the applicability of the optimal value settings as the process changes and considering that the production data collected at different time scales contain different process information, this study proposes a dynamic correction method for the optimal value settings of the solution purification process at multiple time scales. First, considering the low-frequency testing data that can reflect the operation effect, the low-frequency correction is realized by combining mechanism knowledge and expert experience. Second, based on the characteristic that the high-frequency detection data can reflect the changing operating status in time, a supervised self-organizing map method is proposed to classify the changing trends in the operating status. Finally, an integrated, spatiotemporal, just-in-time learning method (with multiple changing trends in the operating status) is proposed to realize high-frequency correction. The experimental results show that the proposed method can dynamically correct the optimal value settings and reduce resource consumption while ensuring product quality. • A dynamic correction method at multiple time scales is proposed. • A fuzzy correction method is proposed for low-frequency correction. • A supervised SOM method is proposed to classify the operating status changing trend. • An improved just-in-time learning method is proposed for high-frequency correction. [ABSTRACT FROM AUTHOR]

Our aim was to evaluate the efficacy and safety of multimodal cocktail intercostal injection for the relief of chest pain after costal cartilage harvest for rhinoplasty. Consecutive patients who underwent costal cartilage harvest during rhinoplasty were prospectively assigned as per patient preference to group A (injection containing ropivacaine, parecoxib sodium, epinephrine, and compound betamethasone), group B (intercostal nerve block (ICNB)), or group C (ICNB plus patient-controlled analgesia (PCA)). The outcomes were visual analogue scale (VAS) scores for chest pain after costal cartilage harvest, rescue analgesia, complications, and cost during the first two days. Of the 66 patients assessed, 63 (29 patients in group A, 13 in group B, and 21 in group C) were eligible and included. The VAS scores in group A were significantly lower than those in groups B and C (all p<0.001). Group A had a significantly lower rate of rescue analgesia due to a VAS score of more than 4 (3.45%, 1/29) compared with group B (46.15%, 6/13; p=0.001) and group C (28.57%, 6/21; p=0.012). Complications were observed only in group C (nausea/vomiting 28.57%; dizziness/headache 23.81%), which differed significantly from group A (p=0.002 and 0.006, respectively). The mean cost for group A (US $15 (0)) was significantly lower than it was for group C (US $113.1 (4.4), p<0.05), but higher than it was for group B (US $5.97 (0), p = -). Multimodal cocktail intercostal injection may be superior for chest pain relief after costal cartilage harvest for rhinoplasty compared with ICNB with or without PCA. Further study is warranted. [ABSTRACT FROM AUTHOR]

A hydrometallurgical reactor is the central production unit in a hydrometallurgy process. Due to the correlation between multiple parallel reactions and feeding condition fluctuations, modeling the outlet technical indicator alone is insufficient to express the highly informative reaction state comprehensively. This paper proposes a cascaded modeling approach for comprehensive reaction state perception of a hydrometallurgical reactor by considering the feeding conditions, operation modes, outlet technical indicators, and their relations. First, propose a perception model based on the information of two adjacent reactors for feeding condition perception. Second, develop an online operating mode perception model, combining dynamic feature extraction methods based on dynamic inner principal component analysis and mechanism knowledge. Finally, an outlet technical indicator perception model integrates mechanism and data features for multiple operation modes. The simulation results reveal that the proposed model can comprehensively describe the reaction state and guide on-site control. [ABSTRACT FROM AUTHOR]

Abstract: Dengue virus (DENV) can infect human dendritic cells (DCs), and cause a spectrum of clinical symptoms. Envelope protein of DENV contains three distinct domains, including domain I (DI), domain II (DII) and domain III (DIII), and plays important roles in receptor binding and induction of protective antibodies. Previously, a new DENV-2 type virus (named B strain) with eight gene mutations in DI of the envelope protein was isolated from a dengue hemorrhagic fever patient. BALB/c mice infected with DENV B strain showed more prolonged viremia than mice infected with the New Guinea C (NGC) strain. However, the mechanism of prolonged viremia was not determined. In this study, DI proteins derived from B and NGC strains of DENV were expressed in Rosetta (DE3) host bacteria and purified by affinity chromatography after refolding. A flow cytometry-based binding assay and confocal microscopy indicated that both proteins could bind to human DCs induced from peripheral blood mononuclear cells (PBMCs), but DI of the B strain had a lower affinity than DI of the NGC strain, and viable B virus also show less binding efficiency with DCs. In addition, DI of the NGC strain, but not the B strain, induced IL-12 secretion and phenotypic maturation of DCs, such as up-regulated expression of CD80, CD83, CD86 and HLA-DR. NGC strain could induce more virus specific IgM/IgG. These results suggest that the naturally mutated envelope protein DI of the Chinese B strain of DENV cannot induce DC maturation as high efficiency as that of NGC strain, which may be the partial reason that DENV B strain escapes immune recognition and induce prolonged viremia. The mutated B strain envelope protein is not a good candidate for subunit vaccine target. [Copyright &y& Elsevier]

Abstract: In order to realize the digitization of the shearer control system and master the magnetic performance of the shearer switched reluctance motors drive (SRD), the three-phase 12/8 switched reluctance motors (SRM) used on shearer was studied, and the distribution form of SRM magnetic field of the rotor different position angles (θ=0°, θ=8°, θ=12°, θ=16°, θ=22.5°) were analyzed basing on the finite element theory. The results indicate that: when the θ=0o, the magnetic flux density in the stator and rotor is lower, which is unsaturated state and the magnetic flux leakage is serious, and whether the self-induction magnetic leakage or the mutual inductance magnetic leakage is bigger; when the θ=8° and θ=12°, there is higher local saturation phenomenon on the magnetic pole tips; when the θ=16°, the local saturation phenomenon is relieved and the magnetic leakage is decreased; when the θ=22.5°, there is little local saturation phenomenon, and the magnetic flux leakage is very small, the self-induction magnetic leakage is nearly to zero, the mutual inductance magnetic leakage is negligible. But, there is no saturation phenomenon on the rotor yoke in any position of the rotor. [Copyright &y& Elsevier]

Optimizing the roasting process is essential for achieving high-efficiency production. However, due to lacking key data detection, limited studies are available in this area. To address this challenge, this paper introduces a practical optimization method aimed at operational parameters such as the blast rate to feed rate (RBF) ratio and roasting temperature. First, a first-principles model of the roasting oxidation reaction was established. The model reveals the essential influence of operating parameters on product quality. This model provides a basis for subsequent optimization of operating parameters. Then, to solve the expensive black-box problem, a new optimization framework is proposed. In this framework, agent models are trained via just-in-time learning, which are tailored to the specific characteristics of the incoming mineral sources. The experimental results verify the effectiveness of the model. The proposed optimization method is approved to be adaptable to varying zinc concentrate compositions, facilitating the optimization of more suitable operational parameters. [Display omitted] • A first principle model is developed to achieve roasting process optimization. • A new framework is proposed to overcome the expensive black-box optimization problem. • The first principle model and optimization framework application are verified. [ABSTRACT FROM AUTHOR]

Activation of peracetic acid (PAA) by Fe species is the attractive advanced oxidation processes for the removal of antibiotics. However, achieving optimal performance in many of these processes often requires acidic pH conditions, which impedes practical application. In this study, an iron electrocoagulation (EC) system was devised to for activate PAA and oxidate sulfamethoxazole (SMX). Under optimal conditions, the degradation of SMX by the EC/PAA system reached 96.2% within 15 min, with a pseudo-first order reaction constant of 0.241 min−1, but only consuming 0.044 kW·h/m3. Interestingly, the EC/PAA system showed a high buffering capacity in the initial pH range of 4–8 to maintain the final pH of around 7. The quenching experiments revealed both free radical and non-free radical pathways involved in the oxidation of SMX in the EC/PAA system. Specifically, the active species, including •OH, organic radicals (CH 3 COO• and CH 3 COOO•) and 1O 2 , contribute 86.77%, 5.53% and 7.70%, respectively. These findings suggest that the EC/PAA system has unique advantages and potential for the degradation of antibiotic organics such as SMX in aquatic environments due to its strong oxidative capacity, wide pH range and high buffering capacity. [Display omitted] • PAA was effectively activated by iron electrocoagulation at a wide pH range. • In-situ OH- production on cathode offered unique efficient buffering capacity. • OH was the major reactive oxidant for sulfamethoxazole degradation. • Organic radicals (CH 3 COO• and CH 3 COOO•) and 1O 2 also contributes to the oxidation. [ABSTRACT FROM AUTHOR]

Both Pax3 and Pax7 can activate a large panel of genes involved in muscle stem cell function. Despite a significant overlap in their transcriptional network, functional difference between them is observed. After overexpressing Pax3 or Pax7 in C2C12, we find both Zac1 and GPR39 are upregulated by Pax7 but not Pax3. Further studies suggest Zac1 interacts directly with Pax7, which can regulate GPR39 expression by activating Zac1. In addition, the effect of Zac1/GPR39 system on myogenic progression has been illuminated: Zac1/GPR39 can promote myogenic differentiation and produce type-II muscle fibers. Gait analysis verifies that transplanting GFP-labeled Pax7 RV/siZac1 transfected cells into mdx mice with muscle injury would delay muscle function repair. Molecular mechanism studies reveal the Zac1/GPR39 system is associated with different myogenic functions of Pax3 and Pax7: Pax7 activates Zac1/GPR39, which mediates the phosphorylation of CaMK-II, resulting in p-ERK1/2 dephosphorylation and β-catenin inhibition, that promotes the formation of type-II muscle fibers; cells lacking Zac1/GPR39 system tend to remain stemness and form type-I muscle fibers after induced differentiation. This study will help the better understanding of the molecular mechanism of Pax3 and Pax7 in the regulation of myogenic progression and muscle fiber types, laying the providing suitable targets for the treatment of muscle diseases. [ABSTRACT FROM AUTHOR]

• The length of fracture process zone is determined by finite element analysis. • The size effect of fracture toughness test value is analyzed. • The reason of size effect of fracture toughness test value is revealed. • The crack growth paths and failure characteristics of samples are discussed. In order to investigate the size effect and reason of rock fracture toughness, the split loading test was carried out in the GCTS rock mechanics testing machine using the center-cracked circular disc (CCCD) samples with diameters of 50 mm, 100 mm, 150 mm and 205 mm, respectively. The lengths of fracture process zone (l FPZ) were determined by the maximum normal stress criterion. The size effect of the l FPZ , fracture toughness test value (K Ic), and fracture energy (G f) were analyzed. The influence of the l FPZ on the size effect of the K Ic was revealed. The crack growth paths and failure characteristics of the samples were discussed. The results show that the l FPZ and the K Ic increase linearly with the sample size, and there is obvious size effect within the range of the test. The K Ic and the l FPZ do not always increase linearly with the size in a larger size range, but gradually stabilize by extrapolation analysis. The l FPZ increases with the size, which means the release of stored energy increases with the size corresponding to the size effect of the G f , and in turn leads to the size effect of the K Ic. It is helpful to deeply understand the cause of the size effect reason of rock fracture toughness. [ABSTRACT FROM AUTHOR]

As the most critical variable in the zinc roasting process, the roasting temperature has been heavily researched for stable control through its average value. However, relying solely on the average temperature cannot convey the entire temperature field information necessary to achieve the optimal production state. To address this, This paper initially proposes a control scheme for the zinc roasting temperature field. First, a computational fluid dynamics (CFD) temperature field model was established through the mechanism of the roasting process. The influence of the feeding position on the temperature field was incorporated into the mechanism model, which provided the basis for the subsequent real-time control. Second, a convolutional Q-learning network (CQLN) is proposed to learn the mapping from state and action to Q value. CQLN can fully mine the spatial information of the temperature field. Then, the feed rate and feed location are adjusted in real-time to obtain the optimal roasting temperature field. Finally, extensive comparative experiments were conducted. Experimental results show that control performance of the proposed method is better than that of the comparison methods, with more uniform temperature distribution and smaller steady-state error. [ABSTRACT FROM AUTHOR]

• BPI 23 -Fcγ significantly improves the survival of lethal multi-drug-resistant (MDR) Acinetobacter baumannii infection-induced pneumonia. • BPI23-Fcγ eliminates MDR A. baumannii effectively by direct bactericidal activity. • BPI23-Fcγ reduces endotoxaemia by neutralizing endotoxin. • BPI23-Fcγ promotes neutrophil recruitment, phagocytosis and maturation. • BPI23-Fcγ and neutrophils enhance bactericidal function synergistically. Antibiotic resistance has become a major threat, contributing significantly to morbidity and mortality globally. Administering non-antibiotic therapy, such as antimicrobial peptides, is one potential strategy for effective treatment of multi-drug-resistant Gram-negative bacterial infections. Bactericidal/permeability-increasing protein (BPI) derived from neutrophils has bactericidal and endotoxin-neutralizing activity. However, the protective roles and mechanisms of BPI in multi-drug-resistant bacterial infections have not been fully elucidated. In this study, a chimeric BPI 23 -Fcγ recombined protein comprising the functional N terminus of BPI and Fcγ was constructed and expressed by adenovirus vector 5 (Ad5). Ad5-BPI 23 -Fcγ or recombinant BPI 23 -Fcγ protein significantly improved the survival of mice with pneumonia induced by a minimal lethal dose of multi-drug-resistant Acinetobacter baumannii or Klebsiella pneumoniae by ameliorating lung pathology and reducing pro-inflammatory cytokines. Transfection with Ad5-BPI 23 -Fcγ significantly decreased the bacterial load and endotoxaemia, which was associated with enhanced bactericidal ability and elevated the phagocytic activity of neutrophils in vitro and in vivo. In addition, Ad5-BPI 23 -Fcγ transfection significantly increased the recruitment of neutrophils to lung, increased the proportion and number of neutrophils in peripheral blood, and promoted the maturation of bone marrow (BM) neutrophils after drug-resistant A. baumannii infection. BPI 23 -Fcγ and neutrophils synergistically enhanced bactericidal activity and decreased pro-inflammatory cytokines. These results demonstrated that the chimeric BPI 23 -Fcγ protein protected mice from pneumonia induced by multi-drug-resistant A. baumannii infection by direct bactericidal effects and promotion of neutrophil recruitment, phagocytosis and maturation. Chimeric BPI 23 -Fcγ may be a promising candidate as a non-antibiotic biological agent for multi-drug-resistant A. baumannii infection. [ABSTRACT FROM AUTHOR]

Abstract Interleukin (IL)-1β and IL-18 play central and detrimental roles in the development of acute lung injury (ALI), and mammalian target of rapamycin (mTOR) is involved in regulating IL-1β and IL-18 production. However, it is not clear whether the mTOR specific inhibitor rapamycin can attenuate lipopolysaccharide (LPS)-induced ALI by modulating IL-1β and IL-18 production. In this study, we found that rapamycin ameliorated LPS-induced ALI by inhibiting NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome-mediated IL-1β and IL-18 secretion. Mechanistically, elevated autophagy and decreased nuclear factor (NF)-κB activation were associated with downregulated IL-1β and IL-18. Moreover, rapamycin reduced leukocyte infiltration in the lung tissue and bronchoalveolar lavage fluid (BALF), and contributed to the alleviation of LPS-induced ALI. Consistently, rapamycin also significantly inhibited IL-1β and IL-18 production by RAW264.7 cells via increased autophagy and decreased NF-κB signaling in vitro. Our results demonstrated that rapamycin protects mice against LPS-induced ALI partly by inhibiting the production and secretion of IL-1β and IL-18. mTOR and rapamycin might represent an appropriate therapeutic target and strategy for preventing ALI induced by LPS. Highlights • Rapamycin, the mTOR inhibitor, can ameliorate LPS-induced acute lung injury. • Rapamycin inhibits the production of IL-1β and IL-18 in vivo and in vitro. • Decreased IL-1β and IL-18 are associated with autophagy and NF-κB activation. • Rapamycin reduces leukocyte infiltration into the lung tissue and BALF. [ABSTRACT FROM AUTHOR]

Abstract: This study aimed to generate a monoclonal antibody (mAb) targeting both tumor necrosis factor-α (TNF-α) and receptor activator of NF-κB ligand (RANKL) and to evaluate the therapeutic effects of this antibody on acute inflammation and osteoporosis. We used hybridoma techniques to generate potential mAbs and enzyme-linked immunosorbent assay (ELISA) to determine their specificity. Crystal violet staining was performed to measure the effective dose of the candidate mAbs. The neutralizing effect of the mAbs was evaluated by TNF-α-mediated cytotoxicity and RANKL-induced osteoclastogenesis assays. We further assessed the therapeutic effect of the mAbs in BALB/c mice with carrageenan-induced acute inflammation and ovariectomy-induced osteoporosis. We successfully generated an IgG1 isotype mAb that recognizes human TNF-α and RANKL, which we named 8G12. The 50% effective dose of 8G12 was approximately 1μg/mL. L929 cells treated with 8G12 exhibited decreased levels of apoptosis (20.04% compared to 63.28% in the positive controls). In addition, treatment with 8G12 inhibited osteoclastogenesis in a dose-dependent manner in vitro. Carrageenan-induced paw edema was significantly reduced in the 8G12-treated mice compared to the positive controls. Treatment with 8G12 also reduced the number of infiltrating leukocytes by more than 50%. The 8G12 treatment not only prevented bone loss but also increased the number, thickness and volume of trabeculae and reduced trabecular separation in ovariectomized mice. Our data suggest that the 8G12 effectively neutralizes the bioactivity of TNF-α and RANKL, ameliorating osteoporosis and inflammation. We therefore propose that 8G12 could be a candidate for generating therapeutic antibodies for treating inflammatory bone diseases. [Copyright &y& Elsevier]

Abstract: This paper aims to explore the influence of vaccination on the diffusion of computer viruses under more reasonable assumptions. By incorporating a vaccination probability in the SIRS model with generalized nonlinear incidence rate, a novel epidemic model of computer viruses is established. A thorough analysis of this model shows that, depending on the value of the basic reproduction number, either the virus-free equilibrium or the endemic equilibrium is globally asymptotically stable. Simulation results not only justify the proposed model, but also demonstrate the effectiveness of vaccination. Based on a parameter analysis for the model, some effective strategies for inhibiting the virus prevalence are posed. [Copyright &y& Elsevier]

Abstract: Targeting tumor necrosis factor-α (TNF-α) and activator of NF-κB ligand (RANKL) has been proved highly successful in rheumatoid arthritis (RA) models and patients. This raises a possibility whether a single agent simultaneously targeting TNF-α and RANKL provides a potential therapeutic opportunity. This study aimed to design a dual functional vaccine and evaluate its therapeutic effects in RA mice model. Standard molecular biological techniques were used to generate human RANKL-TNF-like core fusion protein (RTFP-2) vaccine. High titers of antibodies against human TNF-α and RANKL were elicited and the RTFP-2 antiserum decreased TNF-α mediated apoptosis of L929 cells to 41% compared with 90% in positive controls. In addition, the antiserum completely abrogated osteoclastogenesis in vitro. Immunization with RTFP-2 also reduced the mortality of TNF-α induced cachexia from 56% to 28%. The RANKL-mediated hypercalcemic effects were significantly attenuated in RTFP-2 vaccinated mice. Furthermore, RTFP-2 vaccine significantly mitigated the incidence and severity of CIA via inhibition of inflammation and bone resorption. Our results showed the RTFP-2 vaccine of dual targets ameliorated the symptoms of CIA mice, suggesting the potential possibility to treat inflammatory bone diseases such as RA. [Copyright &y& Elsevier]

Abstract: Objective: To achieve higher tumor detection efficiency, we evaluated a multiplex assay for TM analysis based on the Luminex-100 multiplex suspension bead array. Design: The assay simultaneously determined the concentrations of nine TMs in 1114 human serum specimens (546 patients with tumors, 158 patients with non-tumor inflammatory diseases, and 410 normal controls). The nine TMs were AFP, CEA, CA125, CYFRA 21‐1, CA242, f-PSA, t-PSA, NSE and free β-hCG. The multiplex suspension bead assays were compared with conventional methods used in clinical laboratories. Results: The Luminex assay has the same levels of sensitivity, specificity and accuracy in the prediction of positive tumor specimens as conventional methods. Conclusion: Multiplex suspension bead arrays have promising applications in clinical laboratories. [Copyright &y& Elsevier]

• The development of FPZ of SCB specimens is studied with the help of DIC method. • The length of FPZ is about 2–2.5 times its width at the peak. • The crack opening mode is divided into three stages during the loading process. • FPZ begins to develop around the 65% pre-peak, and the shape of FPZ is strip. • The length and width of FPZ increase with the size of the SCB specimen. In order to investigate the development characteristics and size effect of rock fracture process zone (FPZ), the GCTS RTX-3000 rock mechanics testing machine was used to carry out on semi-circular bend (SCB) sandstone specimens with diameters of 50 mm, 100 mm, 150 mm and 200 mm, respectively. Combined with the digital image correlation (DIC) method, the variations of the displacement field at the crack tip of specimens with different sizes were analyzed. The results show that the crack opening mode of the SCB sandstone specimen has experienced three stages of slow, linear and accelerated growth. Its critical crack opening displacement is about 20 μm. When the load reaches around 65% pre-peak, the FPZ begins to develop. The range of the FPZ reaches the maximum at the peak. The closer to the peak, the faster the development of the FPZ, and the length of the FPZ that increases from 90% pre-peak to peak accounts for 50% of the total FPZ length. The FPZ length of specimens of different sizes at the peak is about 2–2.5 times of the width. As the size of the specimen increases, the length and width of the FPZ increase. The thickness of the specimen has a significant effect on the width of the FPZ. [ABSTRACT FROM AUTHOR]