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Presenteeism at work
\"The cost of absenteeism in organizational functioning has been widely acknowledged and extensively examined in the management disciplines of organizational behavior, organizational theory and strategy (Cascio & Boudreau, 2011). Yet, its alleged flip side \"presenteeeism\" (working while sick) has only recently attracted scholarly attention as a byproduct of organizational restructuring in the wake of the global economic recession, and subsequently as a factor in explaining worsening employee wellbeing, loss productivity, strained team dynamics, hampered implementation of management strategies, and depressed organizational functioning. In the past decade, the rapid advance of digital technologies, i.e. Information and Communication Technologies (ICT) has facilitated agile working and flexibility, but also fuelled the \"always on\" culture (McDowall & Kinman, 2017), which may be more potent in Asian societies working in harmony with the social values of diligence. Alongside this global transformation of \"work taking over life, any time anywhere\", presenteeism may have ceased to be just a work issue: cultural forces, social factors, managerial practices, employees' self-concept, values, motivations, psychological resources will all conspire to make it into a socio-cultural as much as an individual-personal act (of attending work given the circumstance). Unfortunately, the existing work on presenteeism is scattered across a wide range of academic disciplines and under a variety of topics, lacking the coherence and comprehensiveness to address the complexity underlying the phenomenon\"-- Provided by publisher.
Book
Strengthening Materials by Engineering Coherent Internal Boundaries at the Nanoscale
Strengthening materials traditionally involves the controlled creation of internal defects and boundaries so as to obstruct dislocation motion. Such strategies invariably compromise ductility, the ability of the material to deform, stretch, or change shape permanently without breaking. Here, we outline an approach to optimize strength and ductility by identifying three essential structural characteristics for boundaries: coherency with surrounding matrix, thermal and mechanical stability, and smallest feature size finer than 100 nanometers. We assess current understanding of strengthening and propose a methodology for engineering coherent, nanoscale internal boundaries, specifically those involving nanoscale twin boundaries. Additionally, we discuss perspectives on strengthening and preserving ductility, along with potential applications for improving failure tolerance, electrical conductivity, and resistance to electromigration.
Journal Article
Revealing the Maximum Strength in Nanotwinned Copper
The strength of polycrystalline materials increases with decreasing grain size. Below a critical size, smaller grains might lead to softening, as suggested by atomistic simulations. The strongest size should arise at a transition in deformation mechanism from lattice dislocation activities to grain boundary-related processes. We investigated the maximum strength of nanotwinned copper samples with different twin thicknesses. We found that the strength increases with decreasing twin thickness, reaching a maximum at 15 nanometers, followed by a softening at smaller values that is accompanied by enhanced strain hardening and tensile ductility. The strongest twin thickness originates from a transition in the yielding mechanism from the slip transfer across twin boundaries to the activity of preexisting easy dislocation sources.
Journal Article
Transition of dislocation nucleation induced by local stress concentration in nanotwinned copper
Metals with a high density of nanometre-scale twins have demonstrated simultaneous high strength and good ductility, attributed to the interaction between lattice dislocations and twin boundaries. Maximum strength was observed at a critical twin lamella spacing (∼15 nm) by mechanical testing; hence, an explanation of how twin lamella spacing influences dislocation behaviours is desired. Here, we report a transition of dislocation nucleation from steps on the twin boundaries to twin boundary/grain boundary junctions at a critical twin lamella spacing (12–37 nm), observed with
in situ
transmission electron microscopy. The local stress concentrations vary significantly with twin lamella spacing, thus resulting in a critical twin lamella spacing (∼18 nm) for the transition of dislocation nucleation. This agrees quantitatively with the mechanical test. These results demonstrate that by quantitatively analysing local stress concentrations, a direct relationship can be resolved between the microscopic dislocation activities and macroscopic mechanical properties of nanotwinned metals.
Metallic materials with a nanometre-scaled lamella structure can have properties that are very different from their coarser-grained counterparts. Here, the authors demonstrate how dislocations in such a material—nanotwinned copper—can nucleate in two distinctly different mechanisms depending on local stress
Journal Article
Screening Accuracy of SARC-F for Sarcopenia in the Elderly: A Diagnostic Meta-Analysis
Sarcopenia is an age-related disease, which is characterized by a decline in muscle mass and function. It is one of the most important health issues in the elderly and often leads to a high rate and variety of adverse outcomes.
To evaluate the screening accuracy of SARC-F for sarcopenia in the elderly.
We conducted a meta-analysis using articles available in 6 databases including PubMed (Medline), Web of Science, Embase, Cochrane Controlled Register of Trials (CENTRAL), China Knowledge Resource Integrated Database (CNKI), and Wanfang databases from inception to May 2020. Participants: Adults aged 60 years and older.
Sarcopenia was defined by EWGSOP2, EWGSOP, AWGS, FNIH and IWGS. Two authors independently extracted data based on predefined criteria. Where data were available we calculated pooled summary estimates of sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR) and their 95% confidence interval (CI) based on different criteria using the hierarchical logistic regression modeling including bivariate modeling and hierarchical summary receiver operating characteristic (HSROC) modeling.
We included 20 studies, with the prevalence of sarcopenia ranging from 6.42% to 21.56%. The number of the literatures using EWGSOP, EWGSOP2, AWGS, IWGS and FNIH as diagnostic criteria was 13, 4, 13, 8, 7, respectively. Bivariate analysis yielded a pooled sensitivity of 32% (95%CI: 19%–47%), 77% (95%CI: 49%–92%), 27% (95%CI: 16%–42%), 39% (95%CI: 27%–52%), 35% (95%CI: 23%–49%) and a pooled specificity of 86% (95%CI:77%–92%), 63% (95%CI: 43%–79%), 91% (95%CI: 85%–95%), 86% (95%CI: 76%–92%), 89% (95%CI: 81%–93%), respectively. The area under the HSROC curve were 0.68 (95%CI: 0.64–0.72), 0.75 (95%CI: 0.71–0.78), 0.73 (95%CI: 0.69–0.77), 0.67 (95%CI: 0.62–0.71), 0.70 (95%CI: 0.65–0.73), respectively.
The screening accuracy of SARC-F was various based on different diagnostic criteria. There were some limitations for SARC-F, however, considering the higher practicability and specificity for screening sarcopenia in practice, SARC-F was still an effective screening tool for sarcopenia in the elderly. And the screening accuracy of SARC-F needs further exploration when EWGSOP2 is applied as diagnostic criteria and geriatric inpatients are the target participants.
Journal Article
Overexpression of PIK3CA in murine head and neck epithelium drives tumor invasion and metastasis through PDK1 and enhanced TGFβ signaling
Head and neck squamous cell carcinoma (HNSCC) patients have a poor prognosis, with invasion and metastasis as major causes of mortality. The phosphatidylinositol 3-kinase (PI3K) pathway regulates a wide range of cellular processes crucial for tumorigenesis, and
PIK3CA
amplification and mutation are among the most common genetic alterations in human HNSCC. Compared with the well-documented roles of the PI3K pathway in cell growth and survival, the roles of the PI3K pathway in tumor invasion and metastasis have not been well delineated. We generated a
PIK3CA
genetically engineered mouse model (
PIK3CA-GEMM
) in which wild-type
PIK3CA
is overexpressed in head and neck epithelium. Although
PIK3CA
overexpression alone was not sufficient to initiate HNSCC formation, it significantly increased tumor susceptibility in an oral carcinogenesis mouse model.
PIK3CA
overexpression in mouse oral epithelium increased tumor invasiveness and metastasis by increasing epithelial–mesenchymal transition and by enriching a cancer stem cell phenotype in tumor epithelial cells. In addition to these epithelial alterations, we also observed marked inflammation in tumor stroma. AKT is a central signaling mediator of the PI3K pathway. However, molecular analysis suggested that progression of
PIK3CA
-driven HNSCC is facilitated by 3-phosphoinositide-dependent protein kinase (PDK1) and enhanced transforming growth factor β (TGFβ) signaling rather than by AKT. Examination of human HNSCC clinical samples revealed that both PIK3CA and PDK1 protein levels correlated with tumor progression, highlighting the significance of this pathway. In summary, our results offer significant insight into how
PIK3CA
overexpression drives HNSCC invasion and metastasis, providing a rationale for targeting PI3K/PDK1 and TGFβ signaling in advanced HNSCC patients with
PIK3CA
amplification.
Journal Article
Regulation of tumor cell migration and invasion by the H19/let-7 axis is antagonized by metformin-induced DNA methylation
The imprinted, developmentally regulated H19 long noncoding RNA has been implicated in the pathogenesis of diverse human cancers, but the underlying mechanisms have remained poorly understood. Here, we report that H19 promotes tumor cell migration and invasion by inhibiting let-7, a potent tumor suppressor microRNA that functions to posttranscriptionally suppress the expression of oncogenes that regulate cell growth and motility. We show that H19 depletion impairs, whereas its overexpression enhances the motility and invasiveness of tumor cells. These phenomena occur, at least in part through affecting let-7-mediated regulation of metastasis-promoting genes, including
Hmga2
,
c-Myc
and
Igf2bp3
. This H19/let-7-dependent regulation is recapitulated
in vivo
where co-expressions of oncogenes and H19 exist in both primary human ovarian and endometrial cancers. Furthermore, we provide evidence that the anti-diabetic drug metformin inhibits tumor cell migration and invasion, partly by downregulating H19
via
DNA methylation. Our results reveal a novel mechanism underpinning H19-mediated regulation in metastasis and may explain why in some cases increased let-7 expression unexpectedly correlates with poor prognosis, given the widely accepted role for let-7 as a tumor suppressor. Targeting this newly identified pathway might offer therapeutic opportunities.
Journal Article
A Corpus-Based Evaluation of Syntactic Complexity Measures as Indices of College-Level ESL Writers' Language Development
This article reports results of a corpus‐based evaluation of 14 syntactic complexity measures as objective indices of college‐level English as a second language (ESL) writers' language development. I analyzed large‐scale ESL writing data from the Written English Corpus of Chinese Learners (Wen, Wang, & Liang, 2005) using a computational system designed to automate syntactic complexity measurement with 14 measures that have been proposed in second language writing development studies (Lu, 2010). This analysis allows us to investigate the impact of sampling condition on the relationship between syntactic complexity and language development, to identify measures that significantly differentiate between developmental levels, to determine the magnitude at which between‐level differences in each measure reach statistical significance, to assess the pattern of development associated with each measure, and to examine the strength of the relationship between different pairs of measures. This research provides ESL teachers and researchers with useful insights into how these measures can be used effectively as indices of college‐level ESL writers' language development.
Journal Article
miR-130a acts as a potential diagnostic biomarker and promotes gastric cancer migration, invasion and proliferation by targeting RUNX3
MicroRNAs (miRNAs) are abnormally expressed in various types of cancer. miR-130a expression and function in gastric cancer has yet to be elucidated. The aim of the present study was to identify the miR-130a expression and function in gastric cancer. miR-130a expression was examined in gastric cancer cell lines and tissues by RT-qPCR. The diagnostic and prognostic significance of miR-130a in gastric cancer was analyzed by receiver-operating characteristic (ROC) curve and Kaplan-Meier analysis. miR130a expression was identified and the diagnostic significance in the serum of gastric cancer patients and healthy controls was analyzed using RT-qPCR and ROC curves, respectively. A target gene for miR-130a was identified using luciferase reporter assays, and gastric cancer tumorigenesis ability was examined by 3-(4,5-dimethylthazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and Transwell assays. The results showed that miR-130a was upregulated in gastric cancer. The low-miR-130a group had significantly improved overall survival compared to the high-miR-130a group. Furthermore, the expression of miR-130a in plasma in gastric cancer patients was upregulated and diagnostic value for gastric cancer of miR-130a is more effective than the tumor markers carcinoembryonic antigen (CEA) and CA-199. miR-130a directly targeted runt-related transcription factor 3 (RUNX3) and promoted gastric cancer tumorigenesis by targeting RUNX3. miR-130a may therefore be a useful marker for the diagnosis and prognosis of gastric cancer. Additionally, miR-130a was identified as an oncogene that promotes gastric cancer tumorigenesis by targeting RUNX3.
Journal Article
The Relationship of Lexical Richness to the Quality of ESL Learners' Oral Narratives
This study was an examination of the relationship of lexical richness to the quality of English as a second language (ESL) learners’ oral narratives. A computational system was designed to automate the measurement of 3 dimensions of lexical richness, that is, lexical density, sophistication, and variation, using 25 different metrics proposed in the language acquisition literature. This system was used to analyze large‐scale data from the Spoken English Corpus of Chinese Learners (Wen, Wang, & Liang, 2005) together with the vocd utility of the Computerized Language Analysis programs (MacWhinney, 2000), which offers an additional measure of lexical variation, the D measure (Malvern, Richards, Chipere, & Durán, 2004; McKee, Malvern, & Richards, 2000). This comprehensive analysis allowed us to identify measures that correlate strongly with the raters’ judgments of the quality of ESL learners’ oral narratives, as well as to understand the relationships among these measures. This research provides ESL teachers and researchers with a robust tool for assessing the lexical richness of ESL language samples and insights into how lexical richness measures may be effectively used as indices of the quality of ESL learners’ speaking task performance.
Journal Article