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| 1 | Mentors Expressing What They Value Through Their Writings: Emphasizing the Person in Mathematics显示文摘Purpose:This article identifies an issue in mathematics education,that is,the perceived lack of emphasis in recent times of the roles that the'person'plays in the development of mathematics.The purpose is to exami ne how values/valui ng might con tribute to addressi ng the issue.Design/Approach/Methods:“Data”were collected from several purposeful conversations among the three authors.The conversations were audio-recorded and machine-transcribed.The transcript was then subjected to content analysis to identify themes.Findings:The data analysis yielded two novel approaches to raising learners'awareness of the humanness of mathematics.One would be to reframe the values that are operationalized when mathematics is taught and learnt,as processes of valuing which teachers and students engage in,respectively.The sec ond approach would be to ack no wledge that writers of mathematics/mathematicia ns are not simply prese nting kn owledge but are also acti ng as men tors conv eying and transmitting messages about the discipline.Originality/Value:The invoIvement of the'person' in the development of mathematics is not new knowledge,though it can be made more visible in mathematics education.This article identifies two approaches-valuing and mentoring-which are novel in that they are already part of the pedagogical process and thus,accessible. | 余伟忠 张侨平 Alan J.Bishop | 2021 | ECNU Review of Education2021，4，2： | 3 |
| 2 | Patterns of Dwarf expression and brassinosteroid accumulation in tomato reveal the importance of brassinosteroid synthesis during fruit development显示文摘 | TeresaMontoya TakahitoNomura TakaoYokota KerrieFarrar KateHarrison Jonathan G. D.Jones TsuyoshiKaneta YujiKamiya MiklosSzekeres Gerard J.Bishop | 2005 | The Plant Journal2005，，2： | 1 |
| 3 | A system for probing Casimir energy corrections to the condensation energy显示文摘In this article,we present a nanoelectromechanical system(NEMS)designed to detect changes in the Casimir energy.The Casimir effect is a result of the appearance of quantum fluctuations in an electromagnetic vacuum.Previous experiments have used nano-or microscale parallel plate capacitors to detect the Casimir force by measuring the small attractive force these fluctuations exert between the two surfaces.In this new set of experiments,we aim to directly detect the shifts in the Casimir energy in a vacuum due to the presence of the metallic parallel plates,one of which is a superconductor.A change in the Casimir energy of this configuration is predicted to shift the superconducting transition temperature(T_(c))because of the interaction between it and the superconducting condensation energy.In our experiment,we take a superconducting film,carefully measure its transition temperature,bring a conducting plate close to the film,create a Casimir cavity,and then measure the transition temperature again.The expected shifts are smaller than the normal shifts one sees in cycling superconducting films to cryogenic temperatures,so using a NEMS resonator in situ is the only practical way to obtain accurate,reproducible data.Using a thin Pb film and opposing Au surface,we observe no shift in T_(c)>12µK down to a minimum spacing of~70 nm at zero applied magnetic field. | Diego Perez-Morelo Alexander Stange Richard W.Lally Lawrence K.Barrett Matthias Imboden Abhishek Som David K.Campbell Vladimir A.Aksyuk David J.Bishop | 2020 | Microsystems & Nanoengineering2020，6，1： | 1 |
| 4 | Sports compression garments improve resting markers of venous return and muscle blood flow in male basketball players显示文摘Background:The benefits associated with sports compression garments are thought to be closely related to enhanced blood flow.However,findings are equivocal,possibly due to heterogeneity in the techniques used for measuring blood flow,the garment types used,and the pressures applied.This study combined Doppler ultrasound and near-infrared spectroscopy technologies to provide the first comprehensive assessment of the effects of 3 sports compression garment types on markers of venous return and muscle blood flow at rest.Methods:Resting lower-limb blood flow measures(markers of venous return,muscle blood flow,and muscle oxygenation)of 22 elite,junior,male basketball players(age=17.2±0.9 years,mean±SD)were assessed in 4 separate conditions:no compression(CON),compression tights(TIGHTS),compression shorts(SHORTS),and compression socks(SOCKS).Markers of venous return(cross-sectional area,time-averaged mean and peak blood flow velocity,and venous blood flow)were measured via Doppler ultrasound at the popliteal and common femoral veins.Muscle blood flow and muscle oxygenation were measured in the gastrocnemius medialis and vastus lateralis using near-infrared spectroscopy.Results:Popliteal markers of venous return were higher in TIGHTS compared to CON(p<0.01)and SHORTS(p<0.01),with SOCKS values higher compared with CON(p<0.05).Common femoral vein markers of venous return were higher for all conditions compared to CON(p<0.05),with TIGHTS values also higher compared to SOCKS(p<0.05).Gastrocnemius medialis blood flow was higher for TIGHTS compared to CON(p=0.000),SOCKS(p=0.012),and SHORTS(p=0.000),with SOCKS higher compared to SHORTS(p=0.046).Vastus lateralis blood flow was higher for TIGHTS compared to CON(p=0.028)and SOCKS(p=0.019),with SHORTS also higher compared to CON(p=0.012)and SOCKS(p=0.005).Gastrocnemius medialis oxygenation was higher for TIGHTS compared to CON(p=0.003),SOCKS(p=0.033),and SHORTS(p=0.003),with SOCKS higher compared to CON(p=0.044)and SHORTS(p=0.032).Vastus lateralis oxygenation was higher for TIGHTS compared to CON(p=0.020)and SOCKS(p=0.006).Conclusion:Markers of venous return,muscle blood flow,and muscle oxygenation are increased with sports compression garments.TIGHTS are most effective,potentially because of the larger body area compressed. | Shane F.O'Riordan Rod McGregor Shona L.Halson David J.Bishop James R.Broatch | 2023 | Journal of Sport and Health Science2023，12，4： | 1 |
| 5 | 100pT/cm single-point MEMS magnetic gradiometer from a commercial accelerometer显示文摘Magnetic sensing is present in our everyday interactions with consumer electronics and demonstrates the potential for the measurement of extremely weak biomagnetic fields,such as those of the heart and brain.In this work,we leverage the many benefits of microelectromechanical system(MEMS)devices to fabricate a small,low-power,and inexpensive sensor whose resolution is in the range of biomagnetic fields.At present,biomagnetic fields are measured only by expensive mechanisms such as optical pumping and superconducting quantum interference devices(SQUIDs),suggesting a large opportunity for MEMS technology in this work.The prototype fabrication is achieved by assembling micro-objects,including a permanent micromagnet,onto a postrelease commercial MEMS accelerometer using a pick-and-place technique.With this system,we demonstrate a room-temperature MEMS magnetic gradiometer.In air,the sensor’s response is linear,with a resolution of 1.1 nT cm^(−1),spans over 3 decades of dynamic range to 4.6µT cm^(−1),and is capable of off-resonance measurements at low frequencies.In a 1mTorr vacuum with 20 dB magnetic shielding,the sensor achieves a 100 pT cm^(−1) resolution at resonance.This resolution represents a 30-fold improvement compared with that of MEMS magnetometer technology and a 1000-fold improvement compared with that of MEMS gradiometer technology.The sensor is capable of a small spatial resolution with a magnetic sensing element of 0.25 mm along its sensitive axis,a>4-fold improvement compared with that of MEMS gradiometer technology.The calculated noise floor of this platform is 110 fTcm^(−1) Hz−1/2,and thus,these devices hold promise for both magnetocardiography(MCG)and magnetoencephalography(MEG)applications. | Josh Javor Alexander Stange Corey Pollock Nicholas Fuhr David J.Bishop | 2020 | Microsystems & Nanoengineering2020，6，1： | 1 |
| 6 | Modular next generation fast-neutron detector for portal monitoring显示文摘Nuclear nonproliferation is of critical importance for global security.Dangerous fissile materials including highly enriched uranium and weapons-grade plutonium are especially important to detect.Active interrogation techniques may result in much better sensitivity but are difficult with conventional portal monitors that rely on detecting thermal neutrons.Also,most conventional portal monitoring systems rely on ^(3)He,which has a finite and continually decreasing supply.By designing a highly segmented array of organic scintillators,we posit that we can accurately and quickly identify fissile materials,including weapons-grade plutonium and highly enriched uranium,being smuggled.We propose a new design for a fast-neutron detector that overcomes the limitations of the current generation of portal monitors.MCNP6 simulations have been performed in conjunction with the UMPBT statistical model to determine the sensitivity limitations of the proposed detector.Results suggest that the proposed detector may be 10 times more efficient than current-generation thermal neutron detectors and may be able to positively identify a 81 mg 235U source in as little as 192 seconds utilizing active interrogation techniques. | E.Aboud S.Ahn G.V.Rogachev V.E.Johnson J.Bishop G.Christian E.Koshchiy C.E.Parker D.P.Scriven | 2022 | Nuclear Science and Techniques2022，33，1： | 0 |
| 7 | Analysis of a Casimir-driven parametric amplifier with resilience to Casimir pull-in for MEMS single-point magnetic gradiometry显示文摘The Casimir force,a quantum mechanical effect,has been observed in several microelectromechanical system(MEMS)platforms.Due to its extreme sensitivity to the separation of two objects,the Casimir force has been proposed as an excellent avenue for quantum metrology.Practical application,however,is challenging due to attractive forces leading to stiction and device failure,called Casimir pull-in.In this work,we design and simulate a Casimir-driven metrology platform,where a time-delay-based parametric amplification technique is developed to achieve a steady-state and avoid pull-in.We apply the design to the detection of weak,low-frequency,gradient magnetic fields similar to those emanating from ionic currents in the heart and brain.Simulation parameters are selected from recent experimental platforms developed for Casimir metrology and magnetic gradiometry,both on MEMS platforms.While a MEMS offers many advantages to such an application,the detected signal must typically be at the resonant frequency of the device,with diminished sensitivity in the low frequency regime of biomagnetic fields.Using a Casimir-driven parametric amplifier,we report a 10,000-fold improvement in the best-case resolution of MEMS single-point gradiometers,with a maximum sensitivity of 6 Hz/(pT/cm)at 1 Hz.Further development of the proposed design has the potential to revolutionize metrology and may specifically enable the unshielded monitoring of biomagnetic fields in ambient conditions. | Josh Javor Zhancheng Yao Matthias Imboden David K.Campbell David J.Bishop | 2021 | Microsystems & Nanoengineering2021，7，5： | 0 |
| 8 | Probing the subcellular nanostructure of engineered human cardiomyocytes in 3D tissue显示文摘The structural and functional maturation of human induced pluripotent stem cell-derived cardiomyocytes(hiPSC-CMs)is essential for pharmaceutical testing,disease modeling,and ultimately therapeutic use.Multicellular 3D-tissue platforms have improved the functional maturation of hiPSC-CMs,but probing cardiac contractile properties in a 3D environment remains challenging,especially at depth and in live tissues.Using small-angle X-ray scattering(SAXS)imaging,we show that hiPSC-CMs matured and examined in a 3D environment exhibit a periodic spatial arrangement of the myofilament lattice,which has not been previously detected in hiPSC-CMs.The contractile force is found to correlate with both the scattering intensity(R^(2)=0.44)and lattice spacing(R^(2)=0.46).The scattering intensity also correlates with lattice spacing(R^(2)=0.81),suggestive of lower noise in our structural measurement than in the functional measurement.Notably,we observed decreased myofilament ordering in tissues with a myofilament mutation known to lead to hypertrophic cardiomyopathy(HCM).Our results highlight the progress of human cardiac tissue engineering and enable unprecedented study of structural maturation in hiPSC-CMs. | Josh Javor Jourdan K.Ewoldt Paige E.Cloonan Anant Chopra Rebeccah J.Luu Guillaume Freychet Mikhail Zhernenkov Karl Ludwig Jonathan G.Seidman Christine E.Seidman Christopher S.Chen David J.Bishop | 2021 | Microsystems & Nanoengineering2021，7，1： | 0 |
| 9 | 中北海西部蔡希斯坦群蒸发岩之上重力驱动的薄次拉伸:计算机辅助剖面复原技术的应用显示文摘正断层作用和盐构造作用对北海中生代和第三纪地层的沉积及随后的变形起着重要的控制作用。除了先前证明了的盐撤离、溶解和差异沉积负裁等机理之外,还认识到了倾斜盐层上重力驱动薄皮拉伸对北海盆地的发育起着重要的作用。工业用剖面复原软件被用来简化由中北海西部的一个解释过的区域数据库所选择的地震剖面的深度转换、复原和脱压实,并能改善解释精度,用图示并定量地描述与盐有关的拉伸。本研究的结果表明:蔡希斯坦群蒸发岩是于二叠纪时期沉积在一个浅凹盆地中的。二叠系透镜体是由蒸发岩之上的向斜盆地和地堑中的局部沉积作用形成的。当可流动的盐充填到背斜核中时,层状的盐发生褶皱。自早侏罗世以来,与裂谷期后沉降有关的区域性掀斜和沉积负荷的增加,致使异地的中生代和第三纪地层因流动盐层之上的重力扩张而拉伸,它使得异地岩体与下伏原地的晚古生界岩体之间产生滑离。上凹的铲状正断层向下消失在盐层中,向上伸展到上覆盖层层序中,并且在各个地质时代活动,造成异体岩体内地层变厚和褶皱。反向和同向正断层发育,生成复杂的向上分支的断层体系。从图上看,铲状断层呈曲线雁行状排列,由转换冲断层连接。断层一般宽3~7km,厚2~3km,长7~10km。侏罗纪—第三纪期间,盐运动是由盖层的活动性拉伸驱动的,导致盐充填到由断块旋转所产生的可能空间中。因此,盐隆起就出现在拉伸位置的下方。铲状断层的倾向通常与盐底面的倾向相同,尽管还有一些较大的反向区域性断层。在拉伸期间,区域倾斜增加到5°左右。它对盐层上的动力驱动拉伸来说是足够了。已出现了约6%的总拉伸。中北海西部已证实的重力驱动的薄皮拉伸是一种在北海盆地别的地方也能识别出的一种现象,并可与安哥拉近海、巴西、Nova Scotia和墨西哥湾已证实的类似现象相对比。 | Daniel J.Bishop 蔡伟 | 1996 | 国外油气勘探1996，8，2： | 0 |
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