243 research outputs found
Using Social Media to Improve Student-Instructor Communication in an Online Learning Environment
The lack of effective faculty-student interaction has been identified as a main contributor to the high dropout rate in online education. For this paper, the authors conducted an empirical study using a social networking tool, specifically Facebook, to improve student-instructor communication and student performance in an online learning environment. They recruited three sections of an introductory IT course at a public university and divided them into two groups: (1) a treatment group where Facebook was used as an additional communication tool and (2) a control group where the course setting wasn\u27t changed. The authors surveyed the participants\u27 opinions on the use of Facebook in the treatment group, and collected participants\u27 academic performance data for both the treatment and control groups. Their research findings show that the use of Facebook as a supplemental communication method can help an instructor better reach out to students, reduce a course\u27s failure rate, and improve student course performance
Perceptions of Information Systems Security Compliance: An Empirical Study in Higher Education Setting
Ensuring information systems security policy compliance is an integral part of the security program of any organization. This paper investigated the perceptions of different stakeholder groups towards information security policy compliance constructs of Unified Model of Information Security Compliance (UMISPC) [1] in a higher education environment. The research findings showed that faculty/staff generally has higher tendency towards security policy compliance comparing to students in a higher education institution. In addition, students with security knowledge are more incline to have security policy compliance activities. Our finding not only added to the knowledge base of information systems security compliance research, but also offers practical implications
An Evaluation Framework for Selecting Collaboration Systems for Student Teamwork
Collaboration technologies play an increasingly important role in student teamwork in universities. With the proliferation of collaboration systems on the market and the wide range of features they offer, choosing an appropriate system can be an overwhelming task for college students. In this paper, the authors present an empirical study that aimed to help college instructors and students assess and select appropriate collaboration systems for their teamwork needs. They first identified and ranked the important features of collaboration systems for students through a web-based survey. Based on the survey results, the authors built an evaluation framework, in the form of weighted scoring tables, to help students systematically choose technologies that met their collaborative needs. They further demonstrated how to use those scoring tables for an undergraduate capstone class that had a term-long team project. The implications and future directions of the authors\u27 study are also discussed
Quantum Microscopy of Cancer Cells at the Heisenberg Limit
Entangled biphoton sources exhibit nonclassical characteristics and have been
applied to novel imaging techniques such as ghost imaging, quantum holography,
and quantum optical coherence tomography. The development of wide-field quantum
imaging to date has been hindered by low spatial resolutions, speeds, and
contrast-to-noise ratios (CNRs). Here, we present quantum microscopy by
coincidence (QMC) with balanced pathlengths, which enables super-resolution
imaging at the Heisenberg limit with substantially higher speeds and CNRs than
existing wide-field quantum imaging methods. QMC benefits from a configuration
with balanced pathlengths, where a pair of entangled photons traversing
symmetric paths with balanced optical pathlengths in two arms behave like a
single photon with half the wavelength, leading to 2-fold resolution
improvement. Concurrently, QMC resists stray light up to 155 times stronger
than classical signals. The low intensity and entanglement features of
biphotons in QMC promise nondestructive bioimaging. QMC advances quantum
imaging to the microscopic level with significant improvements in speed and CNR
toward bioimaging of cancer cells. We experimentally and theoretically prove
that the configuration with balanced pathlengths illuminates an avenue for
quantum-enhanced coincidence imaging at the Heisenberg limit.Comment: 20 pages, 4 figures; Supplementary Information 15 pages, 9 figure
Single Image Super Resolution via Neighbor Reconstruction
Super Resolution (SR) is a complex, ill-posed problem where the aim is to construct the mapping between the low and high resolution manifolds of image patches. Anchored neighborhood regression for SR (namely A+ Â [27]) has shown promising results. In this paper we present a new regression-based SR algorithm that overcomes the limitations of A+ and benefits from an innovative and simple Neighbor Reconstruction Method (NRM). This is achieved by vector operations on an anchored point and its corresponding neighborhood. NRM reconstructs new patches which are closer to the anchor point in the manifold space. Our method is robust to NRM sparsely-sampled points: increasing PSNR by 0.5 dB compared to the next best method. We comprehensively validate our technique on standardised datasets and compare favourably with the state-of-the-art methods: we obtain PSNR improvement of up to 0.21 dB compared to previously-reported work
Akt/mTOR mediated induction of bystander effect signaling in a nucleus independent manner in irradiated human lung adenocarcinoma epithelial cells
Towards General and Efficient Online Tuning for Spark
The distributed data analytic system -- Spark is a common choice for
processing massive volumes of heterogeneous data, while it is challenging to
tune its parameters to achieve high performance. Recent studies try to employ
auto-tuning techniques to solve this problem but suffer from three issues:
limited functionality, high overhead, and inefficient search.
In this paper, we present a general and efficient Spark tuning framework that
can deal with the three issues simultaneously. First, we introduce a
generalized tuning formulation, which can support multiple tuning goals and
constraints conveniently, and a Bayesian optimization (BO) based solution to
solve this generalized optimization problem. Second, to avoid high overhead
from additional offline evaluations in existing methods, we propose to tune
parameters along with the actual periodic executions of each job (i.e., online
evaluations). To ensure safety during online job executions, we design a safe
configuration acquisition method that models the safe region. Finally, three
innovative techniques are leveraged to further accelerate the search process:
adaptive sub-space generation, approximate gradient descent, and meta-learning
method.
We have implemented this framework as an independent cloud service, and
applied it to the data platform in Tencent. The empirical results on both
public benchmarks and large-scale production tasks demonstrate its superiority
in terms of practicality, generality, and efficiency. Notably, this service
saves an average of 57.00% memory cost and 34.93% CPU cost on 25K in-production
tasks within 20 iterations, respectively
16S rRNA gene sequencing reveals the correlation between the gut microbiota and the susceptibility to pathological scars
The gut microbiome profile in patients with pathological scars remains rarely known, especially those patients who are susceptible to pathological scars. Previous studies demonstrated that gut microbial dysbiosis can promote the development of a series of diseases via the interaction between gut microbiota and host. The current study aimed to explore the gut microbiota of patients who are prone to suffer from pathological scars. 35 patients with pathological scars (PS group) and 40 patients with normal scars (NS group) were recruited for collection of fecal samples to sequence the 16S ribosomal RNA (16S rRNA) V3-V4 region of gut microbiota. Alpha diversity of gut microbiota showed a significant difference between NS group and PS group, and beta diversity indicated that the composition of gut microbiota in NS and PS participants was different, which implied that dysbiosis exhibits in patients who are susceptible to pathological scars. Based on phylum, genus, species levels, we demonstrated that the changing in some gut microbiota (Firmicutes; Bacteroides; Escherichia coli, etc.) may contribute to the occurrence or development of pathological scars. Moreover, the interaction network of gut microbiota in NS and PS group clearly revealed the different interaction model of each group. Our study has preliminary confirmed that dysbiosis exhibits in patients who are susceptible to pathological scars, and provide a new insight regarding the role of the gut microbiome in PS development and progression
Soil nitrogen concentration mediates the relationship between leguminous trees and neighbor diversity in tropical forests
Legumes provide an essential service to ecosystems by capturing nitrogen from the atmosphere and delivering it to the soil, where it may then be available to other plants. However, this facilitation by legumes has not been widely studied in global tropical forests. Demographic data from 11 large forest plots (16â60âha) ranging from 5.25° S to 29.25° N latitude show that within forests, leguminous trees have a larger effect on neighbor diversity than non-legumes. Where soil nitrogen is high, most legume species have higher neighbor diversity than non-legumes. Where soil nitrogen is low, most legumes have lower neighbor diversity than non-legumes. No facilitation effect on neighbor basal area was observed in either high or low soil N conditions. The legumeâsoil nitrogen positive feedback that promotes tree diversity has both theoretical implications for understanding species coexistence in diverse forests, and practical implications for the utilization of legumes in forest restoration
Contrasting Soil Bacterial Community, Diversity, and Function in Two Forests in China
Bacteria are the highest abundant microorganisms in the soil. To investigate bacteria community structures, diversity, and functions, contrasting them in four different seasons all the year round with/within two different forest type soils of China. We analyzed soil bacterial community based on 16S rRNA gene sequencing via Illumina HiSeq platform at a temperate deciduous broad-leaved forest (Baotianman, BTM) and a tropical rainforest (Jianfengling, JFL). We obtained 51,137 operational taxonomic units (OTUs) and classified them into 44 phyla and 556 known genera, 18.2% of which had a relative abundance >1%. The composition in each phylum was similar between the two forest sites. Proteobacteria and Acidobacteria were the most abundant phyla in the soil samples between the two forest sites. The Shannon index did not significantly differ among the four seasons at BTM or JFL and was higher at BTM than JFL in each season. The bacteria community at both BTM and JFL showed two significant (P < 0.05) predicted functions related to carbon cycle (anoxygenic photoautotrophy sulfur oxidizing and anoxygenic photoautotrophy) and three significant (P < 0.05) predicted functions related to nitrogen cycle (nitrous denitrificaton, nitrite denitrification, and nitrous oxide denitrification). We provide the basis on how changes in bacterial community composition and diversity leading to differences in carbon and nitrogen cycles at the two forests
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