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Differential Privacy via a Truncated and Normalized Laplace Mechanism

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Journal of Computer Science & Technology 2022年第2期37卷 369-388页

作者： William Croft Jorg-Rudiger Sack Wei Shi school of Computer Science Carleton UniversityOttawa K1S 5B6Canada school of Information Technology Carleton UniversityOttawa K1S 5B6Canada

When querying databases containing sensitive information,the privacy of individuals stored in the database has to be *** guarantees are provided by differentially private mechanisms which add controlled noise to the query ***,most such mechanisms do not take into consideration the valid range of the query being ***,noisy responses that fall outside of this range may potentially be *** rectify this and therefore improve the utility of the mechanism,the commonly-used Laplace distribution can be truncated to the valid range of the query and then ***,such a data-dependent operation of normalization leaks additional information about the true query response,thereby violating the differential privacy ***,we propose a new method which preserves the differential privacy guarantee through a careful determination of an appropriate scaling parameter for the Laplace *** adapt the privacy guarantee in the context of the Laplace distribution to account for data-dependent normalization factors and study this guarantee for different classes of range constraint *** provide derivations of the optimal scaling parameter(i.e.,the minimal value that preserves differential privacy)for each class or provide an approximation *** a result of this work,one can use the Laplace distribution to answer queries in a range-adherent and differentially private *** demonstrate the benefits of our proposed method of normalization,we present an experimental comparison against other range-adherent *** show that our proposed approach is able to provide improved utility over the alternative mechanisms.

关键词： differential privacy Laplace mechanism query range constraint

Modelling die filling with charged particles using DEM/CFD

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Particuology 2012年第2期10卷 229-235页

作者： Emmanuel Nkem Nwose school of Chemical Engineering University of Birmingham Birmingham B15 2TT UK

The effects of electrostatic charge on powder flow behaviour during die filling in a vacuum and in air were analysed using a coupled discrete element method and computational fluid dynamics （DEM]CFD） code, in which long range electrostatic interactions were implemented. The present 2D simulations revealed that both electrostatic charge and the presence of air can affect the powder flow hehaviour during die filling. It was found that the electrostatic charge inhibited the flow of powders into the die and induced a loose packing structure. At the same filling speed, increasing the electrostatic charge led to a decrease in the fill ratio which quantifies the volumetric occupancy of powder in the die. In addition, increasing the shoe speed caused a further decrease in the fill ratio, which was characterised using the concept of critical filling speed, When the electrostatic charge was low, the air/particle interaction was strong so that a lower critical filling speed was obtained for die filling in air than in a vacuum. With high electrostatic charge, the electrostatic interactions became dominant. Consequently, similar fill ratio and critical filling speed were obtained for die filling in air and in a vacuum.

关键词： DEMCFDElectrostaticsDie fillingPowder flowCohesionCharged particles

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Low complexity DCT-based distributed source coding with Gray code for hyperspectral images

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Journal of Systems Engineering and Electronics 2010年第6期21卷 927-933页

作者： Rongke Liu Jianrong Wang Xuzhou Pan school of Electronic and Information Engineering Beihang University B eijing 100191 E R. China

To compress hyperspectral images, a low complexity discrete cosine transform （DCT）-based distributed source coding （DSC） scheme with Gray code is proposed. Unlike most of the existing DSC schemes, which utilize transform in spatial domain, the proposed algorithm applies transform in spectral domain. Set-partitioning-based approach is applied to reorganize DCT coefficients into waveletlike tree structure and extract the sign, refinement, and significance bitplanes. The extracted refinement bits are Gray encoded. because of the dependency along the line dimension of hyperspectral images, low density paritycheck-（LDPC）-based Slepian-Wolf coder is adopted to implement the DSC strategy. Experimental results on airborne visible/infrared imaging spectrometer （AVIRIS） dataset show that the proposed paradigm achieves up to 6 db improvement over DSC-based coders which apply transform in spatial domain, with significantly reduced computational complexity and memory storage.

关键词： image compression hyperspectral images distributed source coding (DSC) discrete cosine transform (DCT) Gray code band-interleaved-by-pixel (bIP).

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Dose of alendronate directly increases trabeculae expansivity without altering bone volume in rat femurs

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World Journal of Orthopedics 2018年第10期9卷 190-197页

作者： Suyany G Weiss Gabrielle O Kuchar Jennifer T Gerber Fernanda Tiboni Carmen Lucia M Storrer Thaís C Casagrande Allan F Giovanini Rafaela Scariot school of health Science Department of Dentistry Positivo University school of health Science Department of Biotecnology Positivo University

AIM To evaluate the effects of sodium alendronate on bone repair in fractures created in appendicular bones. METHODS Wistar rats(n = 36) were allocated into three distinct groups: group C(control), group b1(received 1 mg/kg of alendronate), and group b2(received 3 mg/kg of alendronate). The rats underwent femoral transversal linear fracture surgery using stable internal fixation with a 2.0 mm plate and screw system. Each animal randomly received intraperitoneal applications of sodium alendronate at a dose corresponding to group b1 or b2 three times a week, while the control group received a 0.9% saline solution. Drug administration was performed until euthanasia at 45 d. The femurs were removed and each surgical piece was sent for radiographic, tomographic and microtomographic analysis. Data were submitted to descriptive and inferential statistical analysis(95% confidence interval).RESULTS Quantitative evaluations of bone neoformation did not show differences among the groups in the radiographic(P = 0.341), microtomographic(P = 0.581) and tomographic evaluations(P = 0.171). In the qualitative microtomographic analysis, a smaller distance was observed between the internal bone trabeculae in the groups that used alendronate(P = 0.05). On the other hand, group b2 had a higher amount of bone trabeculae per unit length when compared to the other groups(P = 0.04).CONCLUSION It is likely that the use of alendronate did not have a direct influence on the amount of bone neoformation, however it did influence the bone quality in a dosedependent manner, ultimately affecting the distance and quantity of the trabeculae.

关键词： Alendronate bone regeneration Fracture Femur bisphosphonates

Mesenchymal stem cells secretome:current trends and future challenges

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Neural Regeneration Research 2020年第1期15卷 75-77页

作者： Fabio G.Teixeira Antonio J.Salgado Life and health Sciences Research Institute(ICVS) School of MedicineUniversity of MinhoBragaPortugalICVS/3B’s Associate LabPT Government Associated LabBraga/GuimaraesPortugal

Mesenchymal stem cells(MSCs)secretome:a good candidate for medical biotechnology?Medical biotechnology is currently defined as the application of biotechnological tools for producing multiple technologies and products to health care,becoming an important bridge between different fields,namely neuroscience,regenerative medicine,pharmacology and bio-engineering(Pham,2018).The use and manipulation of stem cells can potentially represent a medical biotechnology breakthrough that brings regenerative medicine to a new ***,over the last decade,the use of stem cells has remarkably been proposed as a regenerative tool,and within it,MSCs have emerged as a promising therapeutic option.

关键词： manipulation breakthrough becoming

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Evaluating modified effects of family factors on intervention to protect primary school students from the impact of heatwave

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Advances in Climate Change Research 2023年第6期14卷 866-872页

作者： Rui ZHANG bo SUN Si-Yuan WU Shui-Ling QU Yan WANG Yu-Jie MENG Song-Wang WANG Xiao-Yuan YAO Shilu TONG Yong-Hong LI Yi-bin CHENG Chinese Center for Disease Control and Prevention Bejing 102206China National Institute of Environmental health Chinese Center for Disease Control and PreventionBeijing 100021China China CDC Key Laboratory of Environment and Population health National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijing 100021China Sprott school of businss Carleton UniversityOttawa Ontario KIS 5B6Canada school of Public health and Social Work Queensland University of Technology BrisbaneBrisbane 4006Australia

Identifying the factors that may impact intervention effectiveness of primary students is crucial for developing targeted intervention strategies on heatwave *** purpose of the study was to assess how the family factors could affect the intervention effects of primary school students to adapt heatwave,using the data from a previously conducted primary school-based intervention *** study recruited 648 students(9-13 years old)and their parents from two primary schools in Dongtai of Jiangsu province,*** May to September 2017,a 5-mon intervention for enhancing knowledge,attitude and practice(KAP)was implemented at the intervention *** students'KAP scores and the family-related information were measured by designed self-administered questionnaires at intervention school and control school separately before and after *** effects of the intervention were explored through the propensity score matching and difference-in-difference method(PSM-DID),and stratifed analysis were conducted by family *** overall KAP score increased by 2.391(95%CI:1.881,2.902)after intervention,which shows that the intervention was *** students whose parents with higher school educational attainment,parents with employment,and household number≤3 achieved significantly higher increment of KAP scores than their *** students whose parents in marriage achieved higher score increasing than parents not in marriage,the difference was *** findings indicated that parental education status,working status and the household size were the influence factors of heatwave adaption interventions for primary school *** interventions should take parental education status,working status and household size into account to improve the effectiveness of heatwave adaption intervention for primary school students.

关键词： Heatwave Intervention Family factors Primary students Parents

Recent Advances in Electrode Design based on One-Dimensional Nanostructure Arrays for Proton Exchange Membrane Fuel Cell Applications

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Engineering 2021年第1期7卷 33-49页

作者： Shangfeng Du school of Chemical Engineering University of BirminghamBirmingham B152TTUK

One-dimensional(1D)Pt-based electrocatalysts demonstrate outstanding catalytic activities and stability toward the oxygen reduction reaction(ORR).Advances in three-dimensional(3D)ordered electrodes based on 1D Pt-based nanostructure arrays have revealed great potential for developing highperformance proton exchange membrane fuel cells(PEMFCs),in particular for addressing the mass transfer and durability challenges of Pt/C nanoparticle *** paper reviews recent progress in the field,with a focus on the 3D ordered electrodes based on self-standing Pt nanowire *** thin-film(NSTF)catalysts are discussed along with electrodes made from Pt-based nanoparticles deposited on arrays of polymer nanowires,and carbon and TiO2 *** on electrodes from Pt-based nanotube arrays are also *** importance of size,surface properties,and the distribution control of 1D catalyst nanostructures is ***,challenges and future development opportunities are addressed regarding increasing electrochemical surface area(ECSA)and quantifying oxygen mass transport resistance for 1D nanostructure array electrodes.

关键词： Proton exchange membrane fuel cell (PEMFC) Electrode One-dimensional(1D) Oxygen reduction reaction(ORR) Catalyst Ordered

Posterior vitreous detachment rate following intravitreal dexamethasone injection

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International Journal of Ophthalmology(English edition) 2019年第8期12卷 1298-1303页

作者： Atilla Alpay Department of Ophthalmology the School of MedicineZonguldak Bülent Ecevit University

AIM: To determine whether intravitreal dexamethasone(DEX) implant induces posterior vitreous detachment or not. METHODS: We retrospectively reviewed 810 eyes of 405 patients who underwent intravitreal DEX implantation due to macular edema caused by diabetic and retinal venous occlusion in our clinic. The eyes having no injection were determined as the control group. The examination findings of the patients before the injection and 3 mo after the injection and optical coherence tomography(OCT) images were scanned. The pre-injection OCT findings and OCT findings of the patients having no posterior vitreous detachment(PVD) and determined to have partial PVD were compared. RESULTS: The separation in vitreoretinal adhesion and total PVD development of DEX-injected 56/208(26.9%) eyes were statistically greater in comparison with the 12/129(9.3%) eyes that had not been injected(P=0.001). PVD development was observed more in the patients that were younger, had larger macula thickness and lower visual acuity. CONCLUSION: It can be stated that intravitreal DEX implant induces PVD development. Prospective, controlled studies are required in order to determine prognosis of vitreoretinal disease in PVD-developed patients and in non-PVD-developed patients.

关键词： dexamethasone implant intravitreal injection vitreoretinal adhesion diabetic macular edema retinal vein occlusion posterior vitreous detchment

ZbTb7A governs estrogen receptor alpha expression in breast cancer

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Journal of Molecular Cell biology 2018年第4期10卷 273-284页

作者： Mary Ellen Molloy Monika Lewinska Amanda K. Williamson Thanh Thao Nguyen Gamze Kuser-Abali Lu Gong Jiawei Yan John b. Little Pier Paolo Pandolfi Zhi-Min Yuan Department of Environmental health John B. Little Center for Radiation Sciences Harvard T.H. Chan School of Public Health Boston MA 02215 USA biotech Research and Innovation Centre Department of Health and Medical Sciences University of Copenhagen Copenhagen Denmark Cancer Genetics Program Beth Israel Deaconess Cancer Center Departments of Medicine and Pathology Beth Israel Deaconess Medical Center Harvard Medical School Boston MA 02215 USA

ZbTb7A, a member of the POZ/bTb and Krüppel （POK） family of transcription factors, has been shown to have a context-dependent role in cancer development and progression. The role of ZbTb7A in estrogen receptor alpha （ERα）-positive breast cancer is largely unknown. Approximately 70% of breast cancers are classified as ERα-positive. ERα carries out the biological effects of estrogen and its expression level dictates response to endocrine therapies and prognosis for breast cancer patients. In this study, we find that ZbTb7A transcriptionally regulates ERα expression in ERα-positive breast cancer cell lines by binding to the ESR1 promoter leading to increased transcription of ERα. Inhibition of ZbTb7A in ERα-positive cells results in decreased estrogen responsiveness as demonstrated by diminished estrogen-response element-driven luciferase reporter activity, induction of estrogen target genes, and estrogen-stimulated growth. We also report that ERα potentiates ZbTb7A expression via a post-translational mechanism, suggesting the presence of a positive feedback loop between ZbTb7A and ERα, conferring sensitivity to estrogen in breast cancer. Clinically, we find that ZbTb7A and ERα are often co-expressed in breast cancers and that high ZbTb7A expression correlates with improved overall and relapse-free survival for breast cancer patients. Importantly, high ZbTb7A expression predicts a more favorable outcome for patients treated with endocrine therapies. Together, these findings demonstrate that ZbTb7A contributes to the transcriptional program maintaining ERα expression and potentially an endocrine therapy-responsive phenotype in breast cancer.

关键词： ZbTb7A ERα breast cancer endocrine therapies