406 research outputs found
How SaaS Application Led To Cloud Enabled Business Innovation: A Case Study from China
Although cloud computing is increasingly viewed as a catalyst for business innovation, many executives wonder whether and how it can enable the emergence of new business opportunities. This research-inprogress case study presents the business drivers and implementation of a leading telecommunication carrier from China in revolutionizing its SaaS application to a cloud enabled service platform in its innovation to develop a multisided platform business model. The preliminary implicatons from the case reveal that to gain value from cloud enabled business innovation, firms need to develop business strategies based on four key elements: customer needs probing, value proposition positioning, cloud enabled platform construction, and ecosystem development
Ultrasonic Assisted Machining of Nickel-Based Superalloy Inconel 718
Inconel 718 has been widely used in industries because of its excellent mechanical properties. However, the machining process, particularly the turning/grinding, of Inconel 718 is still costly due to high cutting force and heavy tool damage. Fortunately, a promising material removal technique, that is, ultrasonic-assisted turning/grinding (called UAT/UAG for simplicity), could potentially play a great role in the high efficiency precision machining of Inconel 718 due to its excellent features such as smaller turning/grinding force, better surface quality, longer tool working life and lower heat generation. However, few attempts have been done on UAT/UAG of Inconel 718. Therefore, in this work, in order to confirm the feasibility of machining Inconel 718 by UAT/UAG, experimental apparatus/equipment has at first been constructed by installing an ultrasonic cutting-unit/spindle on a NC lathe/surface grinder for UAT/UAG operations, and then experimental investigations have been performed to elucidate the fundamental machining characteristics involving Inconel 718 workpiece including the effects of the ultrasonic vibration and the cutting/grinding speed on the work-surface finish, the machining force and temperature, the chip formation, the tool/wheel wears and so on. The obtained results show that grinding forces and surface roughness were decreased in UAT/UAG
Distraction or Connection? An Investigation of Social Media Use at Work
The use of social media in the workplace is controversial. In order to develop a good understanding of social media use at work, this study examines the effects of social media use from both positive and negative sides. Based on two-factor theory, this study proposes that social media use at work engenders distraction and perceived relatedness, which in turn influence job performance. This study further draws on resource matching theory to posit that the perceptual load of the job moderates the effects of social media use at work on distraction and perceived relatedness. A survey will be conducted to collect data and test the research hypotheses. In theoretical terms, this study is expected to contribute to information systems research by investigating both positive and negative outcomes of social media usage. In practical terms, this study sheds light on the usage and management of social media in the workplace
A Case Report of Adult-Onset Alexander Disease with a Tumor-Like Lesion in the Lateral Ventricle
Adult-onset Alexander disease (AOAD) is an autosomal dominant progressive astrogliopathy caused by pathogenic variants in glial fibrillary acidic protein (GFAP). Individuals with this disorder often present with a typical neuroradiologic pattern, including frontal white matter abnormality with contrast enhancement, atrophy and signal intensity changes of the medulla oblongata and upper cervical cord on MRI. Focal lesions are rarely seen in AOAD, which causes concern for primary malignancies. This study aimed to present the case of a 37-year-old male patient initially diagnosed with an astrocytoma in the lateral ventricle that was later identified as GFAP mutation-confirmed AOAD. GFAP sequencing revealed a heterogeneous missense mutation point c.236G>A. Hence, AOAD should be considered in patients with tumor-like lesion brain lesion in association with atrophy of medulla oblongata and upper cervical spinal cord, and frontal white matter abnormality with contrast enhancement
HLA-DRB1 May Be Antagonistically Regulated by the Coordinately Evolved Promoter and 3′-UTR under Stabilizing Selection
HLA-DRB1 is the most polymorphic MHC (major histocompatibility complex) class II gene in human, and plays a crucial role in the development and function of the immune system. Extensive polymorphisms exist in the promoter and 3′-UTR of HLA-DRB1, especially a LTR (Long terminal repeat) element in the promoter, which may be involved in the expression regulation. However, it remains unknown how the polymorphisms in the whole promoter region and 3′-UTR to regulate the gene expression. In this study, we investigated the extensive polymorphisms in the HLA-DRB1 promoter and 3′-UTR, and how these polymorphisms affect the gene expression in both independent and jointly manners. It was observed that most of the haplotypes in the DRB1 promoter and 3′-UTR were clustered into 4 conserved lineages (H1, H2, H3 and H4), and showed high linkage disequilibrium. Compared with H1 and H2 lineage, a LTR element in the promoter of H3 and H4 lineage significantly suppressed the promoter activity, whereas the activity of the linked 3′-UTR increased, leading to no apparent difference in the final expression product between H1/H2 and H3/H4 lineage. Nevertheless, compared with the plasmid with a promoter and 3′-UTR from the same lineage, the recombinant plasmid with a promoter from H2 and a 3′-UTR from H3 showed about double fold increased luciferase activity, Conversely, the recombinant plasmid with a promoter from H3 and a 3′-UTR from H2 resulted in about 2-fold decreased luciferase activity. These results indicate that the promoter and 3′-UTR of HLA-DRB1 may antagonistically regulate the gene expression, which may be subjected to stabilizing selection. These findings may provide a novel insight into the mechanisms of the diseases associated with HLA-DRB1 genes
A Primary Analysis on the Food Recall System: A Hard Mountain for China to Climb
Food safety concerns people's lives and property safety, the repeated food scandals of Chinese food safety brings a great shock at home and abroad. Chinese government has put forward many policies and schemes to solve the repeated food problems in China in recent years. There are several important measures in the process of dealing with the food safety problem. Among them, food recall is the most important and linking one that should be taken when the unsafe food has already flowed into the market. The establishment of Chinese food recall system has a great significance and shows a good start and a positive attitude of China in its long fight of food safety. However, in China, the food recall system is still in the bud and dose not get enough attention, many flaws and imperfection of Chinese food recall system has been revealed in its practical implementation. This paper attempts to find the flaws existing in Chinese food recall system and analyzes the complexity and diversity of Chinese present condition from the perspective of the theory of regulation. It’s concluded that when the food safety supervisory authorities formulate the detailed plans or regulations of food recall system, they should explore a new path of food recall system and consider more the current condition and the specialty of the country rather than just put other countries’ experience rigidly.
The Broad Host Range Phage vB_CpeS_BG3P Is Able to Inhibit Clostridium perfringens Growth
Clostridium perfringens is an important pathogen for both humans and animals, causing human foodborne disease and necrotic enteritis in poultry. In the present study, a C. perfringens-specific phage, vB_CpeS_BG3P (designated as BG3P hereafter), was isolated from chicken farm sewage. Both electron microscopy and phylogenetic analysis suggested that phage BG3P is a novel phage belonging to Siphoviridae family. Phage BG3P exhibited a broad host range against different C. perfringens isolates (90.63% of strains were infected). Sequencing of the complete genome revealed a linear double-stranded DNA (43,528 bp) with 28.65% GC content. After sequence analysis, 73 open reading frames (orf s) were predicted, of which only 13 were annotated with known functions. No tRNA and virulence encoding genes were detected. It should be noted that the protein of orf 15 has 97.92% homology to C. perfringens-specific chloramphenicol resistance protein, which has not been reported for any C. perfringens phage. Phylogenetic analysis of the ssDNA binding protein demonstrated that this phage is closely related to C. perfringens phages phiSM101 and phi3626. In considering future use as an antimicrobial agent, some biological characteristics were observed, such as a good pH (3–11) stability and moderate temperature tolerance (<60 C). Moreover, bacteriophage BG3P showed a good antimicrobial effect against C. perfringens liquid cultures. Thus, phage treatment with MOI ≥ 100 completely inhibited bacterial growth compared to untreated cultures. Although phage BG3P shows good lytic efficiency and broad host range in vitro, future development and application may need to consider removal of the chloramphenicol-like resistance gene or exploring its lysin for future antibacterial applications.This work was supported by the National Key Research and Development Program of China (No. 2018YFE0101900) and the Jiangsu Agricultural Science and Technology Foundation (No. cx(21)1004)
Vegetation change and human-environment interactions in the Qinghai Lake Basin, northeastern Tibetan Plateau, since the last deglaciation
The nature of the interaction between prehistoric humans and their environment, especially the vegetation, has long been of interest. The Qinghai Lake Basin in North China is well-suited to exploring the interactions between prehistoric humans and vegetation in the Tibetan Plateau, because of the comparatively dense distribution of archaeological sites and the ecologically fragile environment. Previous pollen studies of Qinghai Lake have enabled a detailed reconstruction of the regional vegetation, but they have provided relatively little information on vegetation change within the Qinghai Lake watershed. To address the issue we conducted a pollen-based vegetation reconstruction for an archaeological site (YWY), located on the southern shore of Qinghai Lake. We used high temporal-resolution pollen records from the YWY site and from Qinghai Lake, spanning the interval since the last deglaciation (15.3 kyr BP to the present) to quantitatively reconstruct changes in the local and regional vegetation using Landscape Reconstruction Algorithm models. The results show that, since the lateglacial, spruce forest grew at high altitudes in the surrounding mountains, while the lakeshore environment was occupied mainly by shrub-steppe. From the lateglacial to the middle Holocene, coniferous woodland began to expand downslope and reached the YWY site at ∼ 7.1 kyr BP. The living environment of the local small groups of Paleolithic-Epipaleolithic humans (during 15.3–13.1 kyr BP and 9–6.4 kyr BP) changed from shrub-steppe to coniferous forest–steppe. The pollen record shows no evidence of pronounced changes in the vegetation community corresponding to human activity. However, based on a comparison of the local and regional vegetation reconstructions, low values of biodiversity and a significant increase in two indicators of vegetation degradation, Chenopodiaceae and Rosaceae, suggest that prehistoric hunters-gatherers likely disturbed the local vegetation during ∼ 9.0–6.4 kyr BP. Our findings are a preliminary attempt to study human-environment interactions at Paleolithic-Epipaleolithic sites in the region, and they contribute to ongoing environmental archaeology research in the Tibetan Plateau
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