InviCloak: An End-to-End Approach to Privacy and Performance in Web Content Distribution

In today's web ecosystem, a website that uses a Content Delivery Network (CDN) shares its Transport Layer Security (TLS) private key or session key with the CDN. In this paper, we present the design and implementation of InviCloak, a system that protects the confidentiality and integrity of a user and a website's private communications without changing TLS or upgrading a CDN. InviCloak builds a lightweight but secure and practical key distribution mechanism using the existing DNS infrastructure to distribute a new public key associated with a website's domain name. A web client and a website can use the new key pair to build an encryption channel inside TLS. InviCloak accommodates the current web ecosystem. A website can deploy InviCloak unilaterally without a client's involvement to prevent a passive attacker inside a CDN from eavesdropping on their communications. If a client also installs InviCloak's browser extension, the client and the website can achieve end-to-end confidential and untampered communications in the presence of an active attacker inside a CDN. Our evaluation shows that InviCloak increases the median page load times (PLTs) of realistic web pages from 2.0s to 2.1s, which is smaller than the median PLTs (2.8s) of a state-of-the-art TEE-based solution

The Relationship between Teacher Quality and Teaching Effectiveness Perceived by Students from Industrial Vocational High Schools

[[abstract]]This research explores the relationship between teacher quality and teaching effectiveness perceived by students from Industrial Vocational High Schools. The conclusions are: (1) The present conditions of teacher quality and teaching effectiveness perceived by students are positive. (2) With different student “Grade,” “Teacher Gender,” “School Type” and “School Category,” teacher quality perceived by students is significantly different. (3) With different student “Gender” and “School Type,” teaching effectiveness is significantly different. (4) Teacher quality and teaching effectiveness are positively related, meaning the prediction power of teaching effectiveness, with teacher quality as the predictor, is significant

2020 roadmap on two-dimensional materials for energy storage and conversion

Energy storage and conversion have attained significant interest owing to its important applications that reduce CO2 emission through employing green energy. Some promising technologies are included metal-air batteries, metal-sulfur batteries, metal-ion batteries, electrochemical capacitors, etc. Here, metal elements are involved with lithium, sodium, and magnesium. For these devices, electrode materials are of importance to obtain high performance. Two-dimensional (2D) materials are a large kind of layered structured materials with promising future as energy storage materials, which include graphene, black phosporus, MXenes, covalent organic frameworks (COFs), 2D oxides, 2D chalcogenides, and others. Great progress has been achieved to go ahead for 2D materials in energy storage and conversion. More researchers will join in this research field. Under the background, it has motivated us to contribute with a roadmap on ‘two-dimensional materials for energy storage and conversion

Plant 45S rDNA Clusters Are Fragile Sites and Their Instability Is Associated with Epigenetic Alterations

Our previous study demonstrated that 45S ribosomal DNA (45S rDNA) clusters were chromosome fragile sites expressed spontaneously in Lolium. In this study, fragile phenotypes of 45S rDNA were observed under aphidicolin (APH) incubation in several plant species. Further actinomycin D (ActD) treatment showed that transcriptional stress might interfere with chromatin packaging, resulting in 45S rDNA fragile expression. These data identified 45S rDNA sites as replication-dependent as well as transcription-dependent fragile sites in plants. In the presence of ActD, a dramatic switch to an open chromatin conformation and accumulated incomplete 5′ end of the external transcribed spacer (5′ETS) transcripts were observed, accompanied by decreased DNA methylation, decreased levels of histone H3, and increased histone acetylation and levels of H3K4me2, suggesting that these epigenetic alterations are associated with failure of 45S rDNA condensation. Furthermore, the finding that γ-H2AX was accumulated at 45S rDNA sites following ActD treatment suggested that the DNA damage signaling pathway was associated with the appearance of 45S rDNA fragile phenotypes. Our data provide a link between 45S rDNA transcription and chromatin-packaging defects and open the door for further identifying the molecular mechanism involved

Posterior capsule opacification: What's in the bag?

Cataract, a clouding of the lens, is the most common cause of blindness in the world. It has a marked impact on the wellbeing and productivity of individuals and has a major economic impact on healthcare providers. The only means of treating cataract is by surgical intervention. A modern cataract operation generates a capsular bag, which comprises a proportion of the anterior capsule and the entire posterior capsule. The bag remains in situ, partitions the aqueous and vitreous humours, and in the majority of cases, houses an intraocular lens (IOL). The production of a capsular bag following surgery permits a free passage of light along the visual axis through the transparent intraocular lens and thin acellular posterior capsule. Lens epithelial cells, however, remain attached to the anterior capsule, and in response to surgical trauma initiate a wound-healing response that ultimately leads to light scatter and a reduction in visual quality known as posterior capsule opacification (PCO). There are two commonly-described forms of PCO: fibrotic and regenerative. Fibrotic PCO follows classically defined fibrotic processes, namely hyperproliferation, matrix contraction, matrix deposition and epithelial cell trans-differentiation to a myofibroblast phenotype. Regenerative PCO is defined by lens fibre cell differentiation events that give rise to Soemmerring's ring and Elschnig's pearls and becomes evident at a later stage than the fibrotic form. Both fibrotic and regenerative forms of PCO contribute to a reduction in visual quality in patients. This review will highlight the wealth of tools available for PCO research, provide insight into our current knowledge of PCO and discuss putative management of PCO from IOL design to pharmacological interventions

Estimate the Rebound Effect for Household Vehicle Usage Choice by Regression Models

The recent Notice of Proposed Rulemaking (NPRM) published by the Environmental Protection Agency (EPA) proposed less stringent fuel economy standards for a safer affordable fuel-efficient (SAFE) vehicle rule for passenger vehicles and light trucks. With the advancements in the vehicle technology and improving fuel efficiency, the per-mile driving cost of passenger vehicles will reduce. However, this reduction in the driving cost may result in the rise of vehicle miles traveled, which is referred to as the rebound effect. Motivated by observing this unusual behavior on vehicle miles traveled (VMT) as a result of vehicle-related taxation schemes, this study aims at understanding the elasticity of VMT to fuel economy, which will be the reflection of the rebound effect, as well as the difference between elasticity of VMT to fuel price and fuel economy using 2017 National Household Travel Survey (NHTS). The magnitude of the elasticity of VMT to fuel economy is estimated to be between 0.19 and 0.37. This study aids in contemplating the effectiveness of the standards at reducing fuel utilization and related greenhouse gas emissions

Mandarin Chinese teachers across borders: challenges and needs for professional development

The learning and teaching of Mandarin Chinese as a second or foreign language (CSL/CFL) has been gaining momentum around the world, leading to a shortage of qualified Chinese teachers. Thus more research is needed into the training and professional development of Chinese teachers. This study investigates the challenges and difficulties that native Chinese-speaking teachers of Mandarin have encountered in British schools and the professional development that they desire. A questionnaire survey and semi-structured interviews were used for data collection from native Chinese-speaking teachers of Mandarin in Confucius Institutes (Hanban teachers) in the UK. Results show that participants have encountered linguistic, pedagogical and socio-cultural challenges. Major challenges reported by the Hanban teachers include lack of English proficiency and intercultural competence, lack of knowledge about the local education system, and lack of effective pedagogical methods and classroom management skills to work with disruptive students, students with special educational needs, as well as teaching assistants. The study concludes that training and professional development tailored to the local context seems imperative for this group of teachers to facilitate their effective teaching and localisation

Exploring the potential of terahertz time-domain spectroscopy for label-free identification of animal origin of chondroitin sulfate

This study developed a simple method to distinguish the animal source of chondroitin sulfate (CS) through systematic investigations and comparisons of the terahertz (THz) spectral characteristics of CS with different animal sources. CS from shark had the lowest THz absorption coefficient, followed by that from cattle, with CS from piglet exhibiting the highest values. Meanwhile, in case of continuous and no heating, the changing trends of the THz absorption index value of CS from shark source exhibited significant changes, followed by that from cattle and piglet. Based on the Raman spectrum, infrared spectrum, and thermogravimetric analysis, the molecular composition and structure differences between them were the primary causes of the observed results, being related to the physical index of production by different manufacturers. Thus, the THz spectral characteristics of CS exhibit obvious species differences, which can be used in qualitative animal origin identification