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Lumbar disc herniation is among the common phenotypes of degenerative lumbar spine diseases, significantly affecting patients' quality of life. The practice pattern is diverse. Choosing conservative measures or surgical treatments is still controversial in some areas. For those who have failed conservative treatment, surgery with or without instrumentation is recommended, causing significant expenditures and frustrating complications, that should not be ignored. In the article, we performed a literature review and summarized the evidence by subheadings to unravel the cons of surgical intervention for lumbar disc herniation. There are tetrad critical issues about surgical treatment of lumbar disc herniation, i.e., favorable natural history, insufficient evidence in a recommendation of fusion surgery for patients, metallosis, and implant removal. Firstly, accumulating evidence reveals immune privilege and auto-immunity hallmarks of human lumbar discs within the closed niche. Progenitor cells within human discs further expand the capacity with the endogenous repair. Clinical watchful follow-up studies with repeated diagnostic imaging reveal spontaneous resolution for lumbar disc herniation, even calcified tissues. Secondly, emerging evidence indicates long-term complications of lumbar fusion, such as adjacent segment disease, pseudarthrosis, implant failure, and sagittal spinal imbalance, which get increasing attention. Thirdly, systemic and local reactions (metallosis) for metal instrumentation have been noted with long-term health concerns and toxicity. Fourthly, the indications and timing for spinal implant removal have not reached a consensus. Other challenging issues include postoperative lumbar stiffness. The review provided evidence from a negative perspective for surgeons and patients who attempt to choose surgical treatment. Collectively, the emerging underlying evidence questions the benefits of traditional surgery for patients with lumbar disc herniation. Therefore, the long-term effects of surgery should be closely observed. Surgical decisions should be made prudently for each patient.

To date, comparatively little empirical research has been done on Generation Z globally, and the studies that do exist, while informative, have arrived at different, often loosely tied, conclusions. Seeing as how Generation Z is in the process of joining the professional workforce, it is important for decision makers to understand this generation’s value differences and cultural orientation in order to mitigate intergenerational conflicts and ensure a productive workforce going forward. China, meanwhile, is a rising superpower, and its Generation Z will have a significant impact globally. With the generational mix at work changing to accommodate this new generation, this paper presents a critique of current empirical research on this topic in a cross-cultural context and offers recommendations regarding future research directions as these relate to generational shift in China and other non-Western contexts. It is only by better understanding Generation Z that organizations can develop strategies and policies that will ensure a productive, profitable and collaborative environment in the future, one that better takes into account this newest generation’s needs and outlook.

Changzhen Li,1,* Xiaomei Wang,1,* Jingjing Rao,1,* Ye Zeng,1 Jianjun Liu,2 Feng Tang1 1Department of Laboratory Medicine, Wuhan Children’s Hospital (Wuhan Maternal and Child Healthcare Hospital), Tongji Medical College, Huazhong University of Science & Technology, Wuhan, 430015, People’s Republic of China; 2Office of the Dean, Wuhan Children’s Hospital (Wuhan Maternal and Child Healthcare Hospital), Tongji Medical College, Huazhong University of Science & Technology, Wuhan, 430015, People’s Republic of China*These authors contributed equally to this workCorrespondence: Feng Tang; Jianjun Liu, Email tang33feng66@163.com; liujianjun5221@163.comObjective: To analyze bacterial distribution and antibiotic resistance in clinical specimens from a Chinese hospital for evaluating environmental factors’ impact on pathogen prevalence.Methods: From January 2017 to December 2021, we collected 42,854 clinical specimens from hospitalized children and women. The specimens were cultured on various agar plates and incubated at 35°C for 18– 48 h. Their identification was performed using standard biochemical methods and Matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF), whereas antibiotic susceptibilities were determined using the VITEK 2 system. Concurrent environmental data from Wuhan were analyzed for correlations with pathogen prevalence using multiple linear stepwise regression.Results: Of the 24,555 bacterial strains isolated, the majority were gram-positive, and sputum was the most common specimen type. Haemophilus influenzae and Escherichia coli were the most prevalent pathogens in sputum and urine samples, respectively. Notably, H. influenzae and Streptococcus pneumoniae affected children under 6 years of age the most. Furthermore, H. influenzae showed high ampicillin resistance but low cefotaxime resistance; S. pneumoniae was sensitive to penicillin G, and E. coli was resistant to ampicillin but sensitive to cefotetan. The prevalence of multidrug-resistant organisms was below national averages. In terms of seasonality, H. influenzae peaked during late winter and early spring, and environmental analysis indicated positive correlations between PM2.5 and PM10, and H. influenzae and S. pneumoniae prevalence. In addition, NO2 levels were positively correlated with increased S. aureus and M. catarrhalis prevalence; E coli prevalence was negatively correlated with ozone levels.Conclusion: This study provides valuable insights into the distribution and antibiotic resistance patterns of bacterial pathogens in maternal and child healthcare facilities in Wuhan, China. Environmental factors significantly influence the epidemiology of certain bacterial pathogens. Implementing integrated health strategies that combine microbial surveillance with environmental monitoring is needed to effectively manage and prevent bacterial infections.Keywords: epidemiology, multidrug-resistant pathogens, seasonality, particulate matter

Shipeng Chen,1– 3 Mengna Li,1– 3 Changning Xue,1– 3 Xiangting Zhou,1– 3 Jianxia Wei,1– 3 Lemei Zheng,1– 3 Yumei Duan,1– 3 Hongyu Deng,1 Faqing Tang,1 Wei Xiong,1– 3 Bo Xiang,1– 3 Ming Zhou1– 3 1NHC Key Laboratory of Carcinogenesis, Hunan Key Laboratory of Oncotarget Gene, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, 410013, People’s Republic of China; 2Cancer Research Institute, Central South University, Changsha, 410078, People’s Republic of China; 3The Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Central South University, Changsha, 410078, People’s Republic of ChinaCorrespondence: Ming Zhou; Bo Xiang, Email zhouming2001@163.com; xiangbolin@csu.edu.cnPurpose: Cinobufotalin injection has obvious curative effects on liver cancer patients with less toxicity and fewer side effects than other therapeutic approaches. However, the core ingredients and mechanism underlying these anti-liver cancer effects have not been fully clarified due to its complex composition.Methods: Multidimensional network analysis was used to screen the core ingredients, key targets and pathways underlying the therapeutic effects of cinobufotalin injection on liver cancer, and in vitro and in vivo experiments were performed to confirm the findings.Results: By construction of ingredient networks and integrated analysis, eight core ingredients and ten key targets were finally identified in cinobufotalin injection, and all of the core ingredients are tightly linked with the key targets, and these key targets are highly associated with the cell cycle-related pathways, supporting that both cinobufotalin injection and its core ingredients exert anti-liver cancer roles by blocking cell cycle-related pathways. Moreover, in vitro and in vivo experiments confirmed that either cinobufotalin injection or one of its core ingredients, cinobufagin, significantly inhibited cell proliferation, colony formation, cell cycle progression and xenograft tumor growth, and the key target molecules involved in the cell cycle pathway such as CDK1, CDK4, CCNB1, CHEK1 and CCNE1, exhibit consistent changes in expression after treatment with cinobufotalin injection or cinobufagin. Interestingly, some key targets CDK1, CDK4, PLK1, CHEK1, TTK were predicted to bind with multiple of core ingredients of cinobufotalin injection, and the affinity between one of the critical ingredients cinobufagin and key target CDK1 was further confirmed by SPR assay.Conclusion: Cinobufotalin injection was confirmed to includes eight core ingredients, and they play therapeutic effects in liver cancer by blocking cell cycle-related pathways, which provides important insights for the mechanism of cinobufotalin injection antagonizing liver cancer and the development of novel small molecule anti-cancer drugs. Keywords: cinobufotalin injection, liver cancer, cinobufagin, network pharmacology, cell cycle, core ingredients

Xiaochun Zhou,1– 3,&ast; Kaiying He,1,3,&ast; Jing Zhao,1,3 Guohua Wei,3 Qicai You,1,3 Hongxuan Du,1,3 Wenjiao Gu,1,2 Haiyu Niu,1,4 Qiaoying Jin,1,5 Jianqin Wang,3 Futian Tang1,2 1The Second Hospital & Clinical Medical School, Lanzhou University, Lanzhou, Gansu, People’s Republic of China; 2Department of Cardiovascular Disease, The Second Hospital & Clinical Medical School, Lanzhou University, Lanzhou, Gansu, People’s Republic of China; 3Department of Nephrology, The Second Hospital & Clinical Medical School, Lanzhou University, Lanzhou, Gansu, People’s Republic of China; 4Department of Tumor, The Second Hospital & Clinical Medical School, Lanzhou University, Lanzhou, Gansu, People’s Republic of China; 5Cuiying Biomedical Research Center, The Second Hospital & Clinical Medical School, Lanzhou University, Lanzhou, Gansu, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Futian Tang, Department of Cardiovascular Disease, The Second Hospital & Clinical Medical School, Lanzhou University, No. 82, Cuiyingmen, Lanzhou, Gansu, People’s Republic of China, Tel +8613321330515, Email Tangfutian2023@126.comPurpose: To investigate the therapeutic effect and underlying mechanism of a traditional Chinese medicine (TCM) mixture consisting of Astragalus, rhubarb, and saffron in a mouse model of diabetic kidney disease (DKD).Methods: Forty-eight db/db mice received no TCM (DKD model), low-dose TCM, medium-dose TCM, or high-dose TCM, and an additional 12 db/m mice received no TCM (normal control). Intragastric TCM or saline (controls) was administered daily for 24 weeks. Blood glucose, body weight, serum creatinine (SCr), blood urea nitrogen (BUN), blood lipids, and urinary microalbumin were measured every four weeks, and the urinary albumin excretion rate (UAER) was calculated. After 24 weeks, kidney tissues were collected for transcriptome sequencing, and the main functions of these genes were determined via functional enrichment analysis.Results: Compared with the DKD model group, the medium-dose and high-dose TCM groups had significantly decreased levels of SCr, BUN, total cholesterol, triglycerides, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and UAER (all p< 0.05). We identified 42 genes that potentially functioned in this therapeutic response, and the greatest effect on gene expression was in the high-dose TCM group. We also performed functional enrichment analysis to explore the potential mechanisms of action of these different genes.Conclusion: A high-dose of the Astragalus-rhubarb-saffron TCM provided the best prevention of DKD. Analysis of the kidney transcriptome suggested that this TCM mixture may prevent DKD by altering immune responses and oxygen delivery by hemoglobin.Keywords: diabetic kidney disease (DKD), mixture of astragalus, rhubarb, saffron, transcriptome sequencing, db/db mice

Zhaopeng Li,1,&ast; Deyong Bu,1,&ast; Xiaobin Wang,1 Lin Zhu,2 Daoyan Lei,3 Fengling Tang,1 Xianghua Sun,1 Cheng Chen,4 Xiang Ji,5 Song Bai1 1Department of Geriatric General Surgery, the First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, 650000, People’s Republic of China; 2Department of Ultrasound, the Affiliated Nanchong Central Hospital of North Sichuan Medical College, Nanchong, Sichuan, 637000, People’s Republic of China; 3Department of Ultrasound, Jiangchuan District People’s Hospital, Yuxi, Yunnan, 652600, People’s Republic of China; 4Department of Breast Surgery, the First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, 650000, People’s Republic of China; 5Department of Day Surgery, the First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, 650000, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Deyong Bu; Song Bai, Department of Geriatric General Surgery, the First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, 650000, People’s Republic of China, Tel/Fax +86-0871-5324-888, Email pdyka@163.com; baisong523@163.comPurpose: The present study explored the anti-tumor effects of chidamide plus oxaliplatin on colorectal cancer (CRC) and examined its underlying mechanism.Material and Methods: First, the Combination Index (CI) of chidamide and oxaliplatin was evaluated via CCK-8 assay. Second, the effects of chidamide and oxaliplatin monotherapy and the combined treatment on cell proliferation, invasion, migration, and apoptosis were detected. Third, whole-transcriptome RNA sequencing (RNA-seq) was performed to seek the potential targeted gene by which chidamide plus oxaliplatin exerted anti-tumor effects. Fourth, the validation of the targeted gene and the signal pathway it regulated were performed. Finally, the anti-tumor effect of chidamide plus oxaliplatin on mice xenograft was examined.Results: Chidamide and oxaliplatin acted synergistically to inhibit CRC growth in vitro and in vivo (CI< 1). Besides, compared with oxaliplatin monotherapy, chidamide could significantly enhance oxaliplatin-induced inhibition in cell proliferation, invasion, and migration, and promotion in HCT-116 and RKO cell apoptosis (P< 0.05). The RNA-seq displayed that, compared to oxaliplatin monotherapy, RPS27A mRNA was evidently decreased in HCT-116 cells treated with chidamide plus oxaliplatin (P< 0.001). Then, we found RPS27A was highly expressed in CRC tissues and CRC cell lines (P< 0.001). Silence of RPS27A attenuated proliferation and induced apoptosis in HCT-116 and RKO cells via downregulation of MDM2 expression and upregulation of P53. Next, RPS27A overexpression could partially reverse chidamide plus oxaliplatin induced growth inhibition and apoptosis in HCT-116 and RKO cells (P< 0.01). RPS27A overexpression could promote the upregulation of MDM2 and downregulation of P53 after the combined treatment of chidamide with oxaliplatin.Conclusion: Chidamide and oxaliplatin acted synergistically to suppress CRC growth by the inhibition of the RPS27A-MDM2-p53 axis.Keywords: chidamide, oxaliplatin, colorectal cancer, synergism

This paper presents an investigation of the side wall effects on facade flames ejected from the opening (such as a window) of an under-ventilated room fire. Experiments are carried out in a reduced-scale experimental setup, consisting of a cubic fire compartment having an opening with a vertical facade wall and two side walls normal to the façade wall. By changing the distance of the two side walls, the facade flame heights for different opening conditions (width, height) are recorded by a CCD camera. It is found that as the distance of the two side walls decreases the behavior the flame height can be distinguished into two regimes characterized by the dimensionless excess heat release rate, $skew5dot{Q}_{ex}^{ast}$ See Formula in PDF , outside the opening: (a) for the “wall fire” (skew5dot{Q}_{ex}^{ast }$See Formula in PDF ≤ 1.3 ), the flame height is shown to change little with decrease of side wall distance as the dominant entrainment is from the front direction (normal to the facade wall) independent of the side wall distances; (b) for the “axis-symmetrical fire” (\skew5dot{Q}_{ex}^{ast}$ > 1.3), the flame height increases significantly with a decrease in side wall distance as both the entrainment from the two side directions (parallel to the facade wall) and that from the front direction (normal to the facade wall) together apply. A global physically based non-dimensional factor K is then brought forward based on the side wall constraint effect on the facade flame entrainment to characterize the side wall effect on the flame height, by accounting for the dimensionless excess heat release rate, the characteristic length scales of the opening as well as the side wall separation distance. The experimental data for different opening dimensions and side wall distances collapse by using this global non-dimensional factor.

A new effective model for calculation of the equivalent uniform blast load for non-uniform blast load such as close-in explosion of a one-way square and rectangle reinforced concrete slab is proposed in this paper. The model is then validated using single degree of freedom (SDOF) system with the experiments and blast tests for square slabs and rectangle slabs. Test results showed that the model is accurate in predicting the explosive charge weight and stand-off distance to impose a given damage level on the tested RC slabs especially for close-in blast load. It is shown that the new model is more accurate than the conventional SDOF analysis and is running faster than the FE analysis.

In this paper, two loosely coupled single degree of freedom (SDOF) systems are used to generate pressure-impulse diagrams (P-I) with the flexural and direct shear responses of one-way reinforced concrete slabs subjected to blast loading. The effect of span length to height ratio in P-I diagrams is investigated. The numerical calculation results indicate that a slab tends to fail in a direct shear mode if the blast load amplitude is high but of short duration. It tends to fail in flexural failure mode if load amplitude is relatively low and duration is relatively long. And the failure of the slab might be a combination of shear and flexural damage in the dynamic loading region. Based on numerical results, different failure modes are got with different the span length to height ratio on the P-I diagrams. Results indicate that there is only shear failure mode in the P-I diagrams when L/h < 10.9. When L/h > 24.89, there are two damage mode in the P-I diagrams with flexure failure mode and flexure-shear failure mode. When 10.9 < L/h < 24.89, there are three damage modes in the P-I diagrams: shear failure mode, flexure failure mode and flexure-shear failure mode.

Yang Gu,1– 4,&ast; Xingrui Mu,1,3,4,&ast; Yan Zhang,1,3,4 Yunyan Tang,4,5 Ting Zhang,4,6 Fushan Tang1,3,4 1Department of Clinical Pharmacy, Key Laboratory of Basic Pharmacology of Guizhou Province and School of Pharmacy, Zunyi Medical University, Zunyi, 563006, People’s Republic of China; 2Department of Pharmacy, People’s Hospital in Hezhang County, Bijie, 553200, People’s Republic of China; 3Key Laboratory of Basic Pharmacology of Ministry of Education and Joint International Research Laboratory of Ethnomedicine of Ministry of Education, Zunyi Medical University, Zunyi, 563006, People’s Republic of China; 4The Key Laboratory of Clinical Pharmacy of Zunyi City, Zunyi Medical University, Zunyi, 563006, People’s Republic of China; 5Department of Pharmacy, Affiliated Meitan People’s Hospital of Zunyi Medical University, Zunyi, 564100, People’s Republic of China; 6Department of Pharmacy, Guiyang Hospital of Stomatology, Guiyang, 550002, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Fushan Tang, Department of Clinical Pharmacy, Key Laboratory of Basic Pharmacology of Guizhou Province and School of Pharmacy, Zunyi Medical University, Zunyi, Guizhou, People’s Republic of China, Tel +86851 28642337, Fax +86851 28642334, Email fstang@zmu.edu.cn; fstang@vip.163.comObjective: To investigate the effect of psychological contract of outpatients with hospital pharmacists on medication adherence, providing reference for improving the management of patients’ medication adherence from the perspective of pharmacist-patient relationship and psychological contract.Methods: The 8 patients who received medication dispensing service at the outpatient pharmacies at the First Affiliated Hospital of Zunyi Medical University and the Second Affiliated Hospital of Zunyi Medical University were selected for face-to-face in-depth interviews through a purposive sampling method. In order to get more potential information and adjust flexibly according to the actual situation of the interview, the interviews were set as semi-structured, and the interview content was analyzed by using Colaizzi’s seven-step method of phenomenological analysis and NVivo11.0 software.Results: The following four themes about effects of patients’ psychological contract with hospital pharmacists on medication adherence were extracted: from the perspective of patients, the relationship between pharmacists and patients is generally harmonious; pharmacists can basically fulfil their responsibilities; patients’ medication adherence needs to be improved; the status of patients’ psychological contract with hospital pharmacists may affect medication adherence.Conclusion: The psychological contract of outpatients with hospital pharmacists has a positive effect on their medication adherence. Effective management on medication adherence should involve the management on patients’ psychological contract with hospital pharmacists.Keywords: psychological contract, medication adherence, pharmaceutical care, qualitative study

We carry out X-ray absorption spectroscopy experiment at the oxygen K edge in croconic acid (C5H2O5) crystal as a prototype of ferroelectric organic molecular solid, whose electric polarization is generated by proton transfer. The experimental spectrum is well reproduced by the electron-hole excitation theory simulations from configuration generated by ab initio molecular dynamics simulation. When inversion symmetry is broken in the ferroelectric state, the hydrogen bonding environment on the two bonded molecules become inequivalent. Such a difference is sensitively probed by the bound excitation in the pre-edge, which is strongly localized on the excited molecules. Our analysis shows that a satellite peak in the pre-edge will emerge at higher excitation energy, which serves as a clear signature of ferroelectricity in the material.

Stuti Dang,1– 3 Marianne Desir,1– 3 Shiv Lamba,4 Kiranmayee Muralidhar,1 Fei Tang,2 Willy Marcos Valencia5 1Miller School of Medicine, University of Miami, Miami, FL, USA; 2Geriatric Research, Education and Clinical Center, Miami Veterans Affairs Healthcare System, Miami, FL, USA; 3Department of Veterans Affairs Elizabeth Dole Center of Excellence in Veteran and Caregiver Research, Miami, FL, USA; 4Washington University, St. Louis, MO, USA; 5Division of Endocrinology, Diabetes and Metabolic Diseases, Medical University of South Carolina, Charleston, SC, USACorrespondence: Stuti Dang, Email sdang@med.miami.eduIntroduction: Understanding the needs of higher-risk older adult patients can support the delivery of high quality and patient-centered healthcare. We sought to characterize the physical, functional, social and psychological needs of High-Need High-Risk (HNHR) Veterans. We hypothesized that the concept of frailty could be useful in identifying the highest-risk HNHR patients and characterizing their needs.Methods: We conducted a cross-sectional study of Veterans in the Miami Veterans Affairs Healthcare System who were identified as High-Need High-Risk by the Department of Veterans Affairs (VA) using data analytic techniques. We analyzed data of 634 Veterans who completed questionnaires by mail, telephone or in person. We assessed the Veterans’ frailty status and needs in the physical, functional, psychological and social domains. Beyond descriptive statistics, we used Chi-square (χ2) test, one-way ANOVA and Kruskal–Wallis to analyze whether there were differences in Veterans’ needs in relation to frailty status.Results: The HNHR Veterans who participated in the questionnaire had complex needs that spanned the physical, functional, psychological, and social domains. We observed a potential mismatch between functional needs and social support; over two-thirds of respondents endorsed having dependence in at least one ADL but only about a third of respondents reported having a caregiver. Patients with frailty had higher levels of functional dependence and were more likely than the other HNHR respondents to report recent falls, recent hospitalizations, depression, and transportation issues.Conclusion: High-Need High-Risk Veterans have complex needs related to the physical, functional, psychological and social domains. Within the HNHR population, HNHR Veterans with frailty appear to have particularly high levels of risk and multidomain needs. Increased attention to identifying members of these groups and aligning them with biopsychosocial interventions that are targeted to their specific needs may support development of appropriate strategies and care-models to support HNHR Veterans.Keywords: needs assessment, older adults, high need, frailty, biopsychosocial

Although the richness of spatial symmetries has led to a rapidly expanding inventory of possible topological crystalline (TC) phases of electrons, physical realizations have been slow to materialize due to the practical difficulty in ascertaining band topology in realistic calculations. Here, we integrate the recently established theory of symmetry indicators of band topology into first-principles band-structure calculations, and test it on a database of previously synthesized crystals. On applying our algorithm to just 8 out of the 230 space groups, we are able to efficiently unearth topological materials and predict a diversity of topological phenomena, including: a screw-protected three-dimensional TC insulator, β-MoTe 2 , with gapped surfaces except for one-dimensional helical hinge states; a rotation-protected TC insulator, BiBr, with coexisting surface Dirac cones and hinge states; non-centrosymmetric Z 2 topological insulators undetectable using the well-established parity criterion, AgXO (X = Na, K, Rb); a Dirac semimetal MgBi 2 O 6 ; a Dirac nodal-line semimetal AgF 2 ; and a metal with three-fold degenerate band crossing near the Fermi energy, AuLiMgSn. Our work showcases how recent theoretical insights into the fundamentals of band structures can aid in the practical goal of discovering new topological materials.

Nonsymmorphic compounds have attracted much interest owing to their potential nontrivial electronic states. Here, we grew V1−δSb2 single crystal with a nonsymmorphic space group I4/mcm and studied their de Haas–van Alphen oscillations. Orientation-dependent magnetization showed quantum oscillations, allowing determination of the three-dimensional Fermi surface and Berry phase. Our theoretical calculation implied that VSb2's band structures manifest flat bands along the Γ–X path, Dirac band crossings near the P and N points, and in the Γ–Z direction, and nontrivial surface states along the Γ ¯ – Z ¯ line. However, the inconsistencies in observed and calculated quantum oscillation frequencies suggest that VSb2's band structures cannot nicely account for these electronic properties of our samples. This study reveals the profound impact of V vacancies on VSb2's electronic states, implying the possible topological quantum phase transition via defect engineering. [ABSTRACT FROM AUTHOR]