bluuebunny/crossref_metadata_2025 huggingface dataset:
Gut Symbionts Lactobacillus reuteri R2lc and 2010 Encode a Polyketide Synthase Cluster That Activates the Mammalian Aryl Hydrocarbon Receptor
Authors: Özçam Mustafa , Tocmo Restituto , Oh Jee-Hwan , Afrazi Amin , Mezrich Joshua D. , Roos Stefan , Claesen Jan , van Pijkeren Jan-Peter
Published: November 2018

Temporary changes in the composition of the microbiota, for example, by oral administration of probiotics, can modulate the host immune system. However, the underlying mechanisms by which probiotics interact with the host are often unknown. Here, we show that
Lactobacillus reuteri
R2lc and 2010 harbor an orthologous PKS gene cluster that activates the aryl hydrocarbon receptor (AhR). AhR is a ligand-activated transcription factor that plays a key role in a variety of diseases, including amelioration of intestinal inflammation. Understanding the mechanism by which a bacterium modulates the immune system is critical for applying rational selection strategies for probiotic supplementation. Finally, heterologous and/or optimized expression of PKS is a logical next step toward the development of next-generation probiotics to prevent and treat disease.
Initial Characterization of the Two ClpP Paralogs of
Chlamydia trachomatis
Suggests Unique Functionality for Each
Authors: Wood Nicholas A. , Chung Krystal Y. , Blocker Amanda M. , Rodrigues de Almeida Nathalia , Conda-Sheridan Martin , Fisher Derek J. , Ouellette Scot P.
Published: November 2018

Chlamydia trachomatis
is the leading cause of preventable infectious blindness and of bacterial sexually transmitted infections worldwide. Chlamydiae are developmentally regulated obligate intracellular pathogens that alternate between two functional and morphologic forms, with distinct repertoires of proteins. We hypothesize that protein degradation is a critical aspect to the developmental cycle. A key system involved in protein turnover in bacteria is the Clp protease system. Here, we characterized the two chlamydial ClpP paralogs by examining their expression in
Chlamydia
spp., their ability to oligomerize, and their proteolytic activity. This work will help understand the evolutionarily diverse Clp proteases in the context of intracellular organisms, which may aid in the study of other clinically relevant intracellular bacteria.
Epidemiology and Outcomes of Nontyphoidal
Salmonella
Bacteremias from England, 2004 to 2015
Authors: Katiyo Shannon , Muller-Pebody Berit , Minaji Mehdi , Powell David , Johnson Alan P. , De Pinna Elizabeth , Day Martin , Harris Ross , Godbole Gauri
Published: November 2018

Nontyphoidal
Salmonella
(NTS) bacteremia causes hospitalization and high morbidity and mortality. We linked Gastrointestinal Bacteria Reference Unit (GBRU) data to the Hospital Episode Statistics (HES) data set to study the trends and outcomes of NTS bacteremias in England between 2004 and 2015.
Mutations in Influenza A Virus Neuraminidase and Hemagglutinin Confer Resistance against a Broadly Neutralizing Hemagglutinin Stem Antibody
Authors: Prachanronarong Kristina L. , Canale Aneth S. , Liu Ping , Somasundaran Mohan , Hou Shurong , Poh Yu-Ping , Han Thomas , Zhu Quan , Renzette Nicholas , Zeldovich Konstantin B. , Kowalik Timothy F. , Kurt-Yilmaz Nese , Jensen Jeffrey D. , Bolon Daniel N. A. , Marasco Wayne A. , Finberg Robert W. , Schiffer Celia A. , Wang Jennifer P.
Published: November 2018

Influenza A virus is a public health threat for which currently available vaccines are not always effective. Broadly neutralizing antibodies that bind to the highly conserved stem region of the influenza virus hemagglutinin (HA) can neutralize many influenza virus strains. To understand how influenza virus can become resistant or escape such antibodies, we propagated influenza A virus
in vitro
with escalating concentrations of antibody and analyzed viral populations by whole-genome sequencing. We identified HA mutations near and distal to the antibody binding epitope that conferred resistance to antibody neutralization. Additionally, we identified a neuraminidase (NA) mutation that allowed the virus to grow in the presence of high concentrations of the antibody. Virus carrying dual mutations in HA and NA also grew under high antibody concentrations. We show that NA mutations mediate the escape of neutralization by antibodies against HA, highlighting the importance of a balance between HA and NA for optimal virus function.
Antibody Responses toward the Major Antigenic Sites of Influenza B Virus Hemagglutinin in Mice, Ferrets, and Humans
Authors: Sun Weina , Kang Davina S. , Zheng Allen , Liu Sean T. H. , Broecker Felix , Simon Viviana , Krammer Florian , Palese Peter
Published: November 2018

This study dissected the specific antibody responses toward the major antigenic sites and the noncanonical epitopes of influenza B virus hemagglutinin in animals and humans using novel reagents. These findings will guide the design of the next generation of influenza virus vaccines.
Components of the Reovirus Capsid Differentially Contribute to Stability
Authors: Snyder Anthony J. , Wang Joseph Che-Yen , Danthi Pranav
Published: November 2018

Nonenveloped and enveloped viruses are exposed to the environment during transmission to a new host. Protein-protein and/or protein-lipid interactions stabilize the particle and protect the viral genome. Mammalian orthoreovirus (reovirus) is composed of two concentric, protein shells. The μ1 and σ3 proteins form the outer capsid; contacts between neighboring subunits are thought to confer resistance to inactivating agents. We further investigated the determinants of reovirus stability. The outer capsid was disrupted concurrent with the loss of infectivity; virion associated μ1 rearranged into an altered conformation. Heat sensitivity was controlled by σ3; however, particle integrity was enhanced by a single μ1 mutation. In contrast, the inner capsid (core) displayed superior resistance to heating. These findings reveal structural components that differentially contribute to reovirus stability.
Atrial Fibrillation Screen, Management And Guideline Recommended Therapy (AF SMART II) in the rural primary care setting: an implementation study protocol
Authors: Orchard Jessica J , Neubeck Lis , Freedman Ben , Webster Ruth , Patel Anushka , Gallagher Robyn , Li Jialin , Hespe Charlotte Mary , Ferguson Caleb , Zwar Nicholas , Lowres Nicole
Published: November 2018

Introduction

Screening for atrial fibrillation (AF) in people ≥65 years is now recommended by guidelines and expert consensus. While AF is often asymptomatic, it is the most common heart arrhythmia and is associated with increased risk of stroke. Early identification and treatment with oral anticoagulants can substantially reduce stroke risk. The general practice setting is ideal for opportunistic screening and provides a natural pathway for treatment for those identified.

This study aims to investigate the feasibility of implementing screening for AF in rural general practice using novel electronic tools. It will assess whether screening will fit within an existing workflow to quickly and accurately identify AF, and will potentially inform a generalisable, scalable approach.

Methods and analysis

Screening with a smartphone ECG will be conducted by general practitioners and practice nurses in rural general practices in New South Wales, Australia for 3–4 months during 2018–2019. Up to 10 practices will be recruited, and we aim to screen 2000 patients aged ≥65 years. Practices will be given an electronic screening prompt and electronic decision support to guide evidence-based treatment for those with AF. De-identified data will be collected using a clinical audit tool and qualitative interviews will be conducted with selected practice staff. A process evaluation and cost-effectiveness analysis will also be undertaken. Outcomes include implementation success (proportion of eligible patients screened, fidelity to protocol), proportion of people screened identified with new AF and rates of treatment with anticoagulants and antiplatelets at baseline and completion. Results will be compared against an earlier metropolitan study and a ‘control’ dataset of practices.

Ethics and dissemination

Ethics approval was received from the University of Sydney Human Research Ethics Committee on 27 February 2018 (Project no.: 2017/1017). Results will be disseminated through various forums, including peer-reviewed publication and conference presentations.

Trial registration number

ACTRN12618000004268; Pre-results.
Using big data in cattle practice
Authors: Hudson Chris , Kaler Jasmeet , Down Peter
Published: November 2018

The concept of big data, associated data sources and analytics is becoming increasingly talked about both in society as a whole and within the livestock industry. This article provides a clinician‐focused review of what big data means, how it is already influencing cattle farm and veterinary businesses, and where this may lead in the future. Cattle clinicians have a major role to play in making the best use of big data to improve animal health and efficiency.
Laminitis in horses
Authors: Menzies‐Gow Nicola
Published: November 2018

Laminitis is a common and painful condition of adult equids that often results in permanent lameness or euthanasia. In recent years, our knowledge of the condition has developed and this article discusses the current understanding of laminitis and approaches to its treatment and prevention.
Diagnosis of intrathyroidal ectopic thymus in thyroid fine needle aspiration samples
Authors: Li Weijie , Dim Daniel , Paulson Lorien , Rivard Douglas
Published: November 2018

Aims

Intrathyroidal ectopic thymus (ITET) is a rare cause of paediatric thyroid nodules. Although ultrasonography of ITET demonstrates a characteristic appearance similar to that of normal thymus, accurate differentiation from other thyroid nodule etiologies by ultrasonography is difficult, and so that fine needle aspiration (FNA) is usually performed for further analysis. The aim of this study was to evaluate the utility of flow cytometry (FCM) in confirming the diagnosis of ITET in thyroid FNA samples.

Methods

Five cases of ITET were retrieved from our thyroid FNA database within a 3-year period. Their clinical information, ultrasonographic features, cytology and FCM findings were retrospectively reviewed. The FCM results were compared with those of 22 T-cell acute lymphoblastic leukaemia/lymphoblastic lymphoma (T-ALL/LBL) cases.

Results

The FNA smears of all five ITET cases demonstrated abundant lymphocytes of variable sizes, which included some immature lymphoid cells. No Hassall’s bodies or atypical epithelioid cells were recognised. By multicolour FCM analysis including antibodies against CD1a, CD2, CD3, CD4, CD5, CD7, CD8, CD10, CD34, TDT and TCR, all ITET cases showed antigen expression patterns consistent with normal thymocyte maturation. All T-ALL/LBL cases exhibited significant immunophenotypic aberrancy.

Conclusions

The diagnosis of ITET based on FNA cytology is often inconclusive. The presence of immature lymphocytes often raises the concern for LBL. FCM with adequate antigen coverage can reliably distinguish ITET from T-ALL/LBL and make the diagnosis of ITET in FNA samples. Avoiding unnecessary further invasive procedures, providing reassurance to clinician and patient, the accurate diagnosis of ITET by FCM in FNA samples is clinically important.
Intergenerational social mobility and allostatic load in Great Britain
Authors: Präg Patrick , Richards Lindsay
Published: November 2018

Background

Intergenerational social mobility is hypothesised to be a stressful process that has a negative effect on health. By examining the relationship between own socioeconomic position, parental socioeconomic position and allostatic load (AL) in a representative sample of the British population, we test this hypothesis.

Methods

Our study uses cross-sectional data from 9851 adult participants of waves 2 and 3 of Understanding Society. The relationship between parental occupational class at age 14 years, respondents’ social class at the time of the interview and AL is explored by means of diagonal reference models, which allow us to disentangle the effects of parental social class, own social class and the mobility process. The AL score comprises the following biomarkers: (1) total cholesterol, (2) high-density lipoprotein cholesterol, (3) triglycerides, (4) glycated haemoglobin, (5) C-reactive protein, (6) fibrinogen, (7) systolic blood pressure, (8) diastolic blood pressure, (9) resting heart rate, (10) body mass index and (11) waist circumference.

Results

AL is particularly high among the stable working class and low among the stable upper class. On average, current class and origin class exert about equal weight on current AL. However, social mobility—regardless of whether upwards or downwards—is not detrimental for AL. Furthermore, we find evidence that class of origin may be less important among those outside the labour market for reasons other than retirement.

Conclusion

Both own social class and parental social class influence AL to a similar extent. However, we find no evidence that mobility trajectories exert any effects, good or bad, on AL.
Correlates of support for a nicotine-reduction policy in smokers with 6-week exposure to very low nicotine cigarettes
Authors: Denlinger-Apte Rachel L , Tidey Jennifer W , Koopmeiners Joseph S , Hatsukami Dorothy K , Smith Tracy T , Pacek Lauren R , McClernon F Joseph , Donny Eric C
Published: November 2018

Background

The US Food and Drug Administration recently issued an advanced notice of proposed rule-making for reducing the nicotine content in cigarettes to a minimally addictive level. Very little is known about whether use of very low nicotine content (VLNC) cigarettes affects support for a nicotine reduction policy.

Objective

This study examined the effects of using VLNC versus usual brand (UB) cigarettes on support for a nicotine reduction policy and determined whether participant characteristics and responses to VLNC cigarettes were associated with policy support.

Methods

Participants from a cigarette trial who were assigned to either 0.4 mg nicotine/g tobacco research cigarettes or their UB for 6 weeks were asked about their support for the policy. χ2tests were used to compare support for the policy between cigarette conditions and logistic regression analyses were conducted to assess covariates associated with policy support.

Findings

Policy support did not differ by condition. After 6 weeks of using VLNC cigarettes, 50% of participants supported the policy, 26% opposed and 24% responded ‘Don’t Know’. Support was higher among those adherent to smoking only VLNC cigarettes (65%) compared with those who were non-adherent (44%). Older participants and those interested in quitting had increased odds of support. Cigarette satisfaction, perceived harm and perceived nicotine content were not significantly associated with support.

Conclusions

Smoking VLNC cigarettes did not affect support for a nicotine reduction policy. Understanding predictors of policy support and opposition will help public health officials to maximise the public health acceptance and impact of this policy (ClinicalTrials.gov Identifier:NCT01681875Post-Results).
Exertional myopathy and hyoid luxation in a greyhound
Authors: Marsh Oliver James Richard , De Risio Luisa
Published: November 2018

A four‐year‐old female neutered greyhound was presented for investigation of back pain and cough one week after an episode of extreme exertion. Investigations revealed severely elevated creatine kinase (CK), but no other haematological, biochemical or urinary abnormalities. MRI of the thoracolumbar spine showed diffuse, bilaterally symmetrical signal changes of the longissimus and iliocostalis muscles. These muscles were mildly hyperintense on T1W and markedly hyperintense on T2W and short tau inversion recovery (STIR) images, with strong contrast enhancement. The signal changes were consistent with muscle oedema, which was attributed to exertional myopathy. MRI of the pharynx demonstrated ceratohyoid‐epihyoid subluxation. This dog made a complete recovery with two weeks of conservative management, which consisted of strict rest and analgesia (carprofen and gabapentin).
CT diagnosis of intermittent type IV paraoesophageal hernia in a dog
Authors: Lodzinska Joanna , Culshaw Geoff , Hall Jon L , Schwarz Tobias , Liuti Tiziana
Published: November 2018

In hiatal hernia, elements of the abdominal cavity herniate through the oesophageal hiatus into the mediastinum. Although they are uncommon in both human and veterinary medicine, patients can develop significant clinical complications such as severe gastrointestinal signs, gastric dilatation and volvulus syndrome, and in some cases death. The most comprehensive classification scheme recognises four types of hiatal hernia. Herein, the authors describe a first report of a dog with subclinical intermittent type IV paraoesophageal hernia. CT assisted a rapid, definitive diagnosis and illustrated both the dynamic nature of this type of hernia and the potential for it to lead to severe respiratory compromise. It also facilitated rapid surgical planning, increasing the likelihood of a successful surgical outcome.
Evaluation of distance-independent competition indices in predicting tree survival and diameter growth
Authors: Sun Shuaichao , Cao Quang V. , Cao Tianjian
Published: November 2018

Competition indices play a significant role in modeling individual-tree growth and survival. In this study, six distance-independent competition indices were evaluated using 200 permanent plots of loblolly pine (Pinus taeda L.). The competition indices were classified into three families: (1) size ratios, which include diameter ratio and basal area ratio; (2) relative position indices, which include basal area of larger trees (BAL) and tree relative position based on the cumulative distribution function (CDF); and (3) partitioned stand density index and relative density. Results indicated that different families of competition indices were suitable for different tree survival or diameter growth prediction tasks. The diameter ratio was superior for predicting tree survival, whereas the relative position indices (BAL and CDF) performed best for predicting tree diameter growth, with CDF receiving the highest rank.
Ambroxol attenuates cisplatin-induced hepatotoxicity and nephrotoxicity via inhibition of p-JNK/p-ERK
Authors: Bishr Abeer , Sallam Nada , Nour El-Din Mahmoud , Awad Azza S. , Kenawy Sanaa A.
Published: November 2018

Hepatotoxicity and nephrotoxicity are important drawbacks of cisplatin. The objective of this study is to evaluate the ability of ambroxol in 2 different doses (35 and 70 mg/kg, i.p.) to protect liver and kidney from damage induced by a single dose of cisplatin (10 mg/kg, i.p.) in comparison with N-acetylcysteine (250 mg/kg, i.p.). Inflammatory, oxidative stress, and apoptotic biomarkers were investigated to show the influence of ambroxol on hepatotoxicity and nephrotoxicity. Ambroxol decreased the elevated activity of liver enzymes (aspartate aminotransferase and alanine aminotransferase) and kidney function tests (blood urea nitrogen and creatinine). Ambroxol mitigated cisplatin inflammatory damage by inhibition of tumor necrosis factor-α, interleukin-1β, and nuclear factor kappa-B and elevation of nuclear factor erythroid 2-related factor 2. Moreover, ambroxol inhibited oxidative damage indicated by reduction of malondialdehyde and replenished the store of reduced glutathione likely by upregulating glutathione reductase and superoxide dismutase. Elevation of phosphorylated c-Jun N-terminal kinases (p-JNK) and phosphorylated extracellular signal-regulated kinase (p-ERK) were attenuated by ambroxol associated with a decrease in the expression of caspase-3; these results were consistent with histopathological results. These results recommend ambroxol to be co-administered with cisplatin in cancer patients to ameliorate liver and kidney damage, and this was confirmed by MTT assay.
SMEs as Extended Enterprises: A 360-Degree Model for Profiling SMEs Stakeholder Involvement in R&D
Authors: Vuori Vilma , Vesalainen Jukka , Helander Nina
Published: November 2018

This study increases knowledge on SMEs as extended enterprises, particularly from the viewpoint of stakeholder involvement in firms’ R&D activity. Previous research holds that stakeholder involvement benefits firms’ R&D performance, but tends to approach stakeholder involvement by focusing on one or two stakeholder groups at a time. This paper explores the roles and intensity of involvement of different stakeholders in the R&D processes of SMEs and presents a 360-degree model based on prior research to empirically profile the SMEs to see where their gaps in the stakeholder potential are. The study was conducted with multiple qualitative case studies and contributes to the debates on SMEs’ R&D processes and stakeholder perspective on business. This research offers a synthetizing view of the involvement of different stakeholders’ in R&D, an approach that enables to consider SMEs as extended enterprises.
BIOMECHANICAL MODELING AND SIMULATION OF SUBCUTANEOUS ADIPOSE TISSUE BASED ON LINEAR ELASTIC AND HYPERELASTIC MODEL
Authors: WANG MONAN , LIANG JIANAN , MAO ZHIYONG
Published: November 2018

The biomechanical modeling and simulation of human tissue are the basic part of virtual surgery system. As an important human soft tissue, the biomechanical modeling and simulation method of subcutaneous adipose tissue are urgent problems to be solved in virtual surgery system. In this paper, biomechanical modeling and simulation of subcutaneous adipose tissue were completed based on linear elastic and hyperelastic finite element model. First, the deformation process of subcutaneous adipose tissue was divided into two stages: Initial loading stage and later loading stage. Furthermore, the linear elastic model at initial loading stage and the nonlinear elastic model at later loading stage were established, respectively. Then, the biomechanical model of subcutaneous adipose tissue was solved based on the finite element method. Finally, the linear finite element calculation was included in nonlinear finite element calculations, and finite element simulation program of the subcutaneous adipose tissue was compiled in Visual Studio environment. The accuracy of the model was verified by comparing the simulation results with the experimental results. The efficiency of finite element simulation program of the linear and nonlinear hybrid model is evaluated by comparing the simulation time with the single linear model and the hyperelastic model.
PREDICTION OF THE SPATIO-TEMPORAL GAIT PARAMETERS USING INERTIAL SENSOR
Authors: LIU JIAN , LOCKHART THURMON , KIM SUKWON
Published: November 2018

Monitoring human gait is essential to quantify gait issues associated with fall-prone individuals as well as other gait-related movement disorders. Being portable and cost-effective, ambulatory gait analysis using inertial sensors is considered a promising alternative to traditional laboratory-based approach. The current study aimed to provide a method for predicting the spatio-temporal gait parameters using the wrist-worn inertial sensors. Eight young adults were involved in a laboratory study. Optical motion analysis system and force-plates were used for the assessment of baseline gait parameters. Spatio-temporal features of an Inertial Measurement Unit (IMU) on the wrist were analyzed. Multi-variate correlation analyses were performed to develop gait parameter prediction models. The results indicated that gait stride time was strongly correlated with peak-to-peak duration of wrist gyroscope signal in the anterio-posterior direction. Meanwhile, gait stride length was successfully predicted using a combination model of peak resultant wrist acceleration and peak sagittal wrist angle. In conclusion, current study provided the evidence that the wrist-worn inertial sensors are capable of estimating spatio-temporal gait parameters. This finding paves the foundation for developing a wrist-worn gait monitor with high user compliance.
PD CONTROL WITH DESIRED GRAVITY COMPENSATION FOR A NOVEL DYNAMIC BRACE
Authors: NIU XINJIAN , YANG CHIFU , HAN JUNWEI , CONG DACHENG , ZHENG SHUTAO , AGRAWAL SUNIL K.
Published: November 2018

A novel dynamic brace for the treatment of idiopathic scoliosis based on parallel-actuated robotic system is proposed in this paper. The new brace can apply corrective forces on patients’ spine actively to correct the abnormal spine. However, the gravity of the dynamic system results in some adverse impacts, such as reducing comfort degree of patients, accuracy loss of rehabilitation force control, big error in direction and value of force. To overcome this problem, a new active force control strategy, proportional-derivative (PD) control with desired-gravity-compensation (DGC), is proposed to improve the effectiveness of scoliosis rehabilitation. Considering the electrically driven system and the environment contacting with the brace, the dynamic model of the active brace system is derived using Kane method. Based on the above mentioned, the force controller with DGC is designed for the brace system to compensate the impact of system gravity. The brace experiment system is built and various experiment tests are performed to verify the proposed control strategy. Experiment results demonstrate that the proposed control strategy, PD control with DGC, can distinctly reduce the influence of the brace system gravity and has more efficient control effectiveness compared with the classical PID controller.
INTERSTITIAL FLUID FLOW BEHAVIOR IN OSTEON WALL UNDER NON-AXISYMMETRIC LOADING: A FINITE ELEMENT STUDY
Authors: WU XIAO-GANG , ZHAO TENG , WU XIAO-HONG , XIE JIANG-LAN , CHEN KUI-JUN , GUO HONG-MEI , LI CHAO-XIN , WANG YAN-QIN , CHEN WEI-YI
Published: November 2018

Physiological loads are non-axisymmetric and can lead to interstitial bone fluid flow, particularly in osteon. According to research, interstitial bone fluid flow plays a key role in bone mechanotransduction. To evaluate the poroelastic responses of a non-axisymmetric loaded osteon, this paper presents a finite element osteon model that is bulit by using the Comsol Multiphysics software. Obtained results show that under the same loading amplitude, the generated pressure and velocity amplitudes in the axial compression loading case are the largest, followed by that in the compressive bending loading, and smallest in the bending case. Moreover, the induced pressure and velocity amplitudes in axial compression loading exhibit an axial symmetrical distribution and axial centrosymmetric distribution in the compressive bending. In the bend loading case, the pressure amplitude presents an antisymmetric distribution, but the velocity amplitude is axially symmetrically distributed. Therefore, the distributions of pressure and velocity are definitely affected by load types, which lead to different bone fluid stimuli in mechanotransduction.
Where to from here?
Authors: Denning Peter J.
Published: November 2018

Our curriculum is not up to the challenges the world is throwing at us.
DIDACache
Authors: Shen Zhaoyan , Chen Feng , Jia Yichen , Shao Zili
Published: November 2018

Key-value caching is crucial to today’s low-latency Internet services. Conventional key-value cache systems, such as Memcached, heavily rely on expensive DRAM memory. To lower Total Cost of Ownership, the industry recently is moving toward more cost-efficient flash-based solutions, such as Facebook’s McDipper [14] and Twitter’s Fatcache [56]. These cache systems typically take commercial SSDs and adopt a Memcached-like scheme to store and manage key-value cache data in flash. Such a practice, though simple, is inefficient due to the huge
semantic gap
between the key-value cache manager and the underlying flash devices.

In this article, we advocate to reconsider the cache system design and directly open device-level details of the underlying flash storage for key-value caching. We propose an enhanced flash-aware key-value cache manager, which consists of a novel unified address mapping module, an integrated garbage collection policy, a dynamic over-provisioning space management, and a customized wear-leveling policy, to directly drive the flash management. A thin intermediate library layer provides a slab-based abstraction of low-level flash memory space and an API interface for directly and easily operating flash devices. A special flash memory SSD hardware that exposes flash physical details is adopted to store key-value items. This co-design approach bridges the semantic gap and well connects the two layers together, which allows us to leverage both the domain knowledge of key-value caches and the unique device properties. In this way, we can maximize the efficiency of key-value caching on flash devices while minimizing its weakness. We implemented a prototype, called DIDACache, based on the Open-Channel SSD platform. Our experiments on real hardware show that we can significantly increase the throughput by 35.5%, reduce the latency by 23.6%, and remove unnecessary erase operations by 28%.
Discriminative and Orthogonal Subspace Constraints-Based Nonnegative Matrix Factorization
Authors: Li Xuelong , Cui Guosheng , Dong Yongsheng
Published: November 2018

Nonnegative matrix factorization (NMF) is one widely used feature extraction technology in the tasks of image clustering and image classification. For the former task, various unsupervised NMF methods based on the data distribution structure information have been proposed. While for the latter task, the label information of the dataset is one very important guiding. However, most previous proposed supervised NMF methods emphasis on imposing the discriminant constraints on the coefficient matrix. When dealing with new coming samples, the transpose or the pseudoinverse of the basis matrix is used to project these samples to the low dimension space. In this way, the label influence to the basis matrix is indirect. Although, there are also some methods trying to constrain the basis matrix in NMF framework, either they only restrict within-class samples or impose improper constraint on the basis matrix. To address these problems, in this article a novel NMF framework named discriminative and orthogonal subspace constraints-based nonnegative matrix factorization (DOSNMF) is proposed. In DOSNMF, the discriminative constraints are imposed on the projected subspace instead of the directly learned representation. In this manner, the discriminative information is directly connected with the projected subspace. At the same time, an orthogonal term is incorporated in DOSNMF to adjust the orthogonality of the learned basis matrix, which can ensure the orthogonality of the learned subspace and improve the sparseness of the basis matrix at the same time. This framework can be implemented in two ways. The first way is based on the manifold learning theory. In this way, two graphs, i.e., the intrinsic graph and the penalty graph, are constructed to capture the intra-class structure and the inter-class distinctness. With this design, both the manifold structure information and the discriminative information of the dataset are utilized. For convenience, we name this method as the name of the framework, i.e., DOSNMF. The second way is based on the Fisher’s criterion, we name it Fisher’s criterion-based DOSNMF (FDOSNMF). The objective functions of DOSNMF and FDOSNMF can be easily optimized using multiplicative update (MU) rules. The new methods are tested on five datasets and compared with several supervised and unsupervised variants of NMF. The experimental results reveal the effectiveness of the proposed methods.
Complex and Ambiguous
Authors: Cha Yoonjeong , Kim Jongwon , Park Sangkeun , Yi Mun Yong , Lee Uichin
Published: November 2018

Stickers, though similar in appearance to emoji, have distinct characteristics because they often contain animation, diverse gestures, and multiple characters and objects. Stickers can convey richer meaning than emoji, but their complexity and placement constraint may result in miscommunication. In this paper, we aim to understand how people perceive emotion in stickers, as well as how miscommunication related to sticker occurs in actual chat contexts. Toward this goal, we conducted an online survey (n = 87) and in-depth interviews (n = 28) in South Korea. We found emotional and contextual aspects of sticker misinterpretation. In particular, emotion misinterpretation mostly happened due to stickers' ambiguous (multiple) facial/bodily expressions and different perception of dynamism in gestures. In real chat settings, there were also contextual misinterpretations where senders and receivers differently interpret stickers' visual representation/reference, or/and corresponding textual messages. Based on these findings, we provide several practical design implications such as context awareness support in sticker interaction.
Data-Driven Proactive Policy Assurance of Post Quality in Community q&a Sites
Authors: Chen Chunyang , Chen Xi , Sun Jiamou , Xing Zhenchang , Li Guoqiang
Published: November 2018

To ensure the post quality, Q&A sites usually develop a list of quality assurance guidelines for "dos and don'ts", and adopt collaborative editing mechanism to fix quality violations. Quality guidelines are mostly high-level principles, and many tacit and context-sensitive aspects of the expected quality cannot be easily enforced by a set of explicit rules. Collaborative editing is a reactive mechanism after low-quality posts have been posted. Our study of collaborative editing data on Stack Overflow suggests that tacit and context-sensitive quality-assurance knowledge is manifested in the editing patterns of large numbers of collaborative edits. Inspired by this observation, we develop and evaluate a Convolutional Neural Network based approach to learn editing patterns from historical post edits for predicting the need of editing a post. Our approach provides a proactive policy assurance mechanism that warns users potential quality issues in a post before it is posted.
Evaluating Crowdworkers as a Proxy for Online Learners in Video-Based Learning Contexts
Authors: Davis Dan , Hauff Claudia , Houben Geert-Jan
Published: November 2018

Crowdsourcing has emerged as an effective method of scaling-up tasks previously reserved for a small set of experts. Accordingly, researchers in the large-scale online learning space have begun to employ crowdworkers to conduct research about large-scale, open online learning. We here report results from a crowdsourcing study (N=135) to evaluate the extent to which crowdworkers and MOOC learners behave comparably on lecture viewing and quiz tasks---the most utilized learning activities in MOOCs. This serves to (i) validate the assumption of previous research that crowdworkers are indeed reliable proxies of online learners and (ii) address the potential of employing crowdworkers as a means of online learning environment testing. Overall, we observe mixed results---in certain contexts (quiz performance and video watching behavior) crowdworkers appear to behave comparably to MOOC learners, and in other situations (interactions with in-video quizzes), their behaviors appear to be disparate. We conclude that future research should be cautious if employing crowdworkers to carry out learning tasks, as the two populations do not behave comparably on all learning-related activities.
Technology to Support Immigrant Access to Social Capital and Adaptation to a New Country
Authors: Hsiao Joey Chiao-Yin , Dillahunt Tawanna R.
Published: November 2018

The key to successful adaptation for immigrants in a new country is their social capital, or those resources embedded in their social networks. Research suggests that information and communication technologies (ICTs) foster immigrants' social capital and facilitate their adaptation. However, it is unclear how recent immigrants use ICTs to develop social capital and how this supports their adaptation needs. We performed semi-structured interviews with thirteen recent immigrants and five long-term immigrants. We found that ICTs and technology-mediated connections: (1) easily addressed immigrants' settlement needs, (2) minimally addressed their financial and cultural needs, and (3) were not used to address their emotional needs. To support recent immigrants' adaptation, we suggest ways for ICTs to (1) reduce uncertainty about meeting local-born populations, (2) foster reciprocity among immigrant communities, and (3) facilitate safe resource exchanges.
Professional Medical Advice at your Fingertips
Authors: Ma Xiaojuan , Gui Xinning , Fan Jiayue , Zhao Mingqian , Chen Yunan , Zheng Kai
Published: November 2018

Timely access to professional medical advice is crucial for patient health outcomes. Traditional offline, one-on-one patient-provider interactions are time consuming and costly. As a result, online "Ask the doctor" (AtD) services have become increasingly popular, where patients and caregivers can obtain advice from medical professionals at a lower information and transaction cost. In this paper, we present an empirical study of Fenda, an innovative AtD platform recently introduced in China where patients and caregivers can consult a wide variety of healthcare professionals for a small fee. Using qualitative research methods, we analyzed how patients and caregivers interact with medical professionals on this platform, focusing on the nature of the questions asked and user strategies to optimize the usage of the platform. We further derived implications for designing better online AtD services connecting patients and caregivers to medical professionals.
Normative Tensions in Shared Augmented Reality
Authors: Poretski Lev , Lanir Joel , Arazy Ofer
Published: November 2018

Novel collaborative technologies afford new modes of behavior, which are often not regulated by established social norms. In particular, shared augmented reality (AR) - where multiple users can create, attach, and interact with the same virtual elements embedded into the physical environment - has the potential to interrupt current social norms of behavior. The objective of our study is to shed light on the ways in which shared AR challenges existing behavioral expectations. Using a simulated lab experimental design, we performed a study of users' interactions in a shared AR setting. Content analysis of participants' interviews reveals users' concerns over the preservation of their self- and social identity, as well as concerns related to personal space and the sense of psychological ownership over one's body and belongings. Our findings also point to the need for regulation of shared AR spaces and design of the technology's control mechanisms.
Fostering Civil Discourse Online
Authors: Rho Eugenia Ha Rim , Mark Gloria , Mazmanian Melissa
Published: November 2018

Linguistic style and affect shape how users perceive and assess political content on social media. Using linguistic methods to compare political discourse on far-left, mainstream and alt-right news articles covering the #MeToo movement, we reveal rhetorical similarities and differences in commenting behavior across the political spectrum. We employed natural language processing techniques and qualitative methods on a corpus of approximately 30,000 Facebook comments from three politically distinct news publishers. Our findings show that commenting behavior reflects how social movements are framed and understood within a particular political orientation. Surprisingly, these data reveal that the structural patterns of discourse among commenters from the two alternative news sites are similar in terms of their relationship to those from the mainstream - exhibiting polarization, generalization, and othering of perspectives in political conversation. These data have implications for understanding the possibility for civil discourse in online venues and the role of commenting behavior in polarizing media sources in undermining such discourse.
The Social Roles of Bots
Authors: Seering Joseph , Flores Juan Pablo , Savage Saiph , Hammer Jessica
Published: November 2018

Bots, or programs designed to engage in social spaces and perform automated tasks, are typically understood as automated tools or as social "chatbots." In this paper, we consider their place alongside users in the emerging social ecosystem of audience participation platforms, through the application of Structural Role Theory. We perform a large-scale analysis of activity levels of user-designed bots on Twitch, finding that they communicate at a much greater rate than any other type of user. We build on a classification scheme derived from prior literature on bot functionalities to identify the roles bots play on Twitch, how these roles vary across different types of Twitch communities, and how users engage with them and vice versa. We conclude with a discussion of what roles are missing and where opportunities lie to re-conceptualize and re-design bots as social actors who help communities grow and evolve.
Liquidity, Leverage, and Regulation 10 Years After the Global Financial Crisis
Authors: Adrian Tobias , Kiff John , Shin Hyun Song
Published: November 2018

The financial system has undergone far-reaching changes since the global financial crisis of 2008. We cast those changes in terms of shifts in the manner in which financial intermediaries manage their balance sheets. We also discuss the regulatory reform agenda, and we review the impact of regulations on market liquidity and credit availability. Current evidence suggests that the financial system has become safer, at limited unintended cost.
Absence of the sulfate transporter SAT-1 has no impact on oxalate handling by mouse intestine and does not cause hyperoxaluria or hyperoxalemia
Authors: Whittamore Jonathan M. , Stephens Christine E. , Hatch Marguerite
Published: November 2018

The anion exchanger SAT-1 [sulfate anion transporter 1 (Slc26a1)] is considered an important regulator of oxalate and sulfate homeostasis, but the mechanistic basis of these critical roles remain undetermined. Previously, characterization of the SAT-1-knockout (KO) mouse suggested that the loss of SAT-1-mediated oxalate secretion by the intestine was responsible for the hyperoxaluria, hyperoxalemia, and calcium oxalate urolithiasis reportedly displayed by this model. To test this hypothesis, we compared the transepithelial fluxes of14C-oxalate,35[Formula: see text], and36Cl−across isolated, short-circuited segments of the distal ileum, cecum, and distal colon from wild-type (WT) and SAT-1-KO mice. The absence of SAT-1 did not impact the transport of these anions by any part of the intestine examined. Additionally, SAT-1-KO mice were neither hyperoxaluric nor hyperoxalemic. Instead, 24-h urinary oxalate excretion was almost 50% lower than in WT mice. With no contribution from the intestine, we suggest that this may reflect the loss of SAT-1-mediated oxalate efflux from the liver. SAT-1-KO mice were, however, profoundly hyposulfatemic, even though there were no changes to intestinal sulfate handling, and the renal clearances of sulfate and creatinine indicated diminished rates of sulfate reabsorption by the proximal tubule. Aside from this distinct sulfate phenotype, we were unable to reproduce the hyperoxaluria, hyperoxalemia, and urolithiasis of the original SAT-1-KO model. In conclusion, oxalate and sulfate transport by the intestine were not dependent on SAT-1, and we found no evidence supporting the long-standing hypothesis that intestinal SAT-1 contributes to oxalate and sulfate homeostasis.

NEW & NOTEWORTHY SAT-1 is a membrane-bound transport protein expressed in the intestine, liver, and kidney, where it is widely considered essential for the excretion of oxalate, a potentially toxic waste metabolite. Previously, calcium oxalate kidney stone formation by the SAT-1-knockout mouse generated the hypothesis that SAT-1 has a major role in oxalate excretion via the intestine. We definitively tested this proposal and found no evidence for SAT-1 as an intestinal anion transporter contributing to oxalate homeostasis.
Early disruption of the alveolar-capillary barrier in a ricin-induced ARDS mouse model: neutrophil-dependent and -independent impairment of junction proteins
Authors: Sapoznikov Anita , Gal Yoav , Falach Reut , Sagi Irit , Ehrlich Sharon , Lerer Elad , Makovitzki Arik , Aloshin Anna , Kronman Chanoch , Sabo Tamar
Published: November 2018

Irrespective of its diverse etiologies, acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) leads to increased permeability of the alveolar-capillary barrier, which in turn promotes edema formation and respiratory failure. We investigated the mechanism of ALI/ARDS lung hyperpermeability triggered by pulmonary exposure of mice to the highly toxic plant-derived toxin ricin. One prominent hallmark of ricin-mediated pulmonary intoxication is the rapid and massive influx of neutrophils to the lungs, where they contribute to the developing inflammation yet may also cause tissue damage, thereby promoting ricin-mediated morbidity. Here we show that pulmonary exposure of mice to ricin results in the rapid diminution of the junction proteins VE-cadherin, claudin 5, and connexin 43, belonging, respectively, to the adherens, tight, and gap junction protein families. Depletion of neutrophils in ricin-intoxicated mice attenuated the damage caused to these junction proteins, alleviated pulmonary edema, and significantly postponed the time to death of the intoxicated mice. Inhibition of matrix metalloproteinase (MMP) activity recapitulated the response to neutrophil depletion observed in ricin-intoxicated mice and was associated with decreased insult to the junction proteins and alveolar-capillary barrier. However, neutrophil-mediated MMP activity was not the sole mechanism responsible for pulmonary hyperpermeability, as exemplified by the ricin-mediated disruption of claudin 18, via a neutrophil-independent mechanism involving tyrosine phosphorylation. This in-depth study of the early stage mechanisms governing pulmonary tissue integrity during ALI/ARDS is expected to facilitate the tailoring of novel therapeutic approaches for the treatment of these diseases.
Bloch-Type Spaces of Minimal Surfaces
Authors: He Guanghua , Fu Xi , Zhu Hancan
Published: November 2018

We study Bloch-type spaces of minimal surfaces from the unit disk D into Rn and characterize them in terms of weighted Lipschitz functions. In addition, the boundedness of a composition operator Cϕ acting between two Bloch-type spaces is discussed.
Experimental Investigation on the Deformation and Fracture of Steel Square Tubes under Double‐Explosion Loadings
Authors: Ji Chong , Yu Yang , Zhou You , Gao Fuyin , Xie Xingbo , Wu Jianyu
Published: November 2018

The experimental investigations on the square tubes with various stand‐off distances and wall thickness were helpful to understand the dynamic response of metal shell under single and double explosion. Therefore, the effect of stand‐off distance, wall thickness, and amounts of explosion on the deformation and damage of the square tubes and the regular pattern of the fracture development was analyzed by dimensions of local plastic deformation, volume of the depression area, and crack type. The result reveals that the deformation and fracture mode of steel square tubes gradually transform from local deformation to rupture with the decrease of wall thickness and stand‐off distance. Besides, the failure degrees of square tubes under a double explosion were relatively higher than those of square tubes under a single explosion. In addition, the experiment indicates that the side corners of the square tube are very vulnerable, and they are damaged easily by the stress concentration and shear effect. The conclusion provides an important scientific basis for the structural design of square‐tube structures and calculation of engineering protection.