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Shear-Wave Splitting and Mantle Flow Beneath the Colorado Plateau and its Boundary with the Great Basin
Shear-wave splitting measurements from SKS and SKKS phases show fast polarization azimuths that are subparallel to North American absolute plate motion within the central Rio Grande Rift (RGR) and Colorado Plateau (CP) through to the western rim of the CP, with anisotropy beneath the CP and central RGR showing a remarkably consistent pattern with a mean fast azimuth of 4 degrees +/- degrees 6 E of N. Approaching the rim from the southeast, fast anisotropic directions become north-northeast-south-southwest (NNE-SSW), rotate counter clockwise to north-south in the CP-GB transition, and then to NNW-SSE in the western Great Basin ( GB). This change is coincident with uppermost mantle S-wave velocity perturbations that vary from +4% beneath the western CP and the eastern edge of the Marysvale volcanic field to about -8% beneath the GB. Corresponding delay times average 1.5 sec beneath the central CP, decrease to approximately 0.8 sec near the CP-GB transition, and increase to about 1.2 sec beneath the GB. For the central CP, we suggest anisotropy predominantly controlled by North American plate motion above the asthenosphere. The observed pattern of westward-rotating anisotropy from the western CP through the CP-GB transition may be influenced to asthenospheric flow around a CP lithospheric keel and/or by vertical flow arising from edge-driven small-scale convection. The anisotropic transition from the CP to the GB thus marks a first-order change from absolute plate motion dominated lithosphere-asthenosphere shear to a new regime controlled by regional flow processes. The NNW-SSE anisotropic fast directions of split SKS waves in the eastern GB area are part of a broad circular pattern of seismic anisotropic fast direction in the central GB that has recently been hypothesized to be due to toroidal flow around the sinking Juan de Fuca-Gorda slab.National Science Foundation EAR 9706094, 9707188, 9707190, 0207812Los Alamos National Laboratory Institute of Geophysics and Planetary PhysicsNational Science Foundation Cooperative EAR-000430Department of Energy National Nuclear Security AdministrationGeological Science
DAMPAK RADIASI ELEKTROMAGNET DAN MIKROPLASTIK TERHADAP KESEHATAN MANUSIA
terhadap kesehatan, antara lain keganasan, autoimun, dan gangguan hormonal. Masih banyak masyarakat yang belum memahami dampak buruk tersebut karena gejala gangguan kesehatan yang ditimbulkan tidak langsung tampak atau terasa, dan umumnya baru disadari beberapa bulan atau tahun kemudian. Hal yang menjadi masalah adalah masyarakat saat ini tidak dapat dipisahkan dari gadget dan berbagai piranti yang menggunakan listrik karena kemajuan teknologi makin canggih. Plastik pun makin banyak digunakan karena sifatnya yang ringan, praktis dan tahan lama. Upaya yang harus dilakukan adalah meningkatkan pengetahuan masyarakat tentang dampak buruk radiasi elektromagnet dan mikroplastik terhadap kesehatan, yaitu dengan meminimalkan pararan radiasielektromagnet dan mikroplasti sekaligus mengupayakan kemampuan tubuh untuk memulihkan diri secara berkesinambungan. Pengetahuan dan kesadaran tentang fenomena gunung es dan empat tahap sakit perlu disosialisasikan kepada masyarakat agar memahami pentingnya upaya preventif dan promotif. Rencana kegiatan berupa sharing knowledge, lomba poster dan lomba memasak sehat kaya antioksidan, serta praktek olahraga qigong agar peserta lebih memahami dan mampu menerapkan dalam kehidupan sehari-hari. Upaya ini sejalan dengan program Kementrian Kesehatan dan Gerakan Masyarakat Hidup Sehat (Germas) untuk mengatasi dampak buruk radiasi electromagnet dan mikroplastik terhadap kesehatan
UPGRADE SISTEM PLTS ATAP TIPE HYBRID-OFF GRID SEBAGAI SUMBER ENERGI UTAMA DALAM BUDIDAYA HIDROPONIK DI UMKM MAESTRO BORNEO HIDROPONIK FARM PALANGKA RAYA
Sistem budidaya dengan sistem hidroponik saat ini telah banyak digemari kalangan masyarakat luas karena tidak memerlukan tanah dan lahan yang luas. Dengan menggunakan sistem hidroponik, tentu hasil panen akan lebih cepat dan optimal namun masih terdapat hal yang perlu diperhatikan seperti pada ketepatan dalam pemberian nutrisi, paparan intensitas cahaya matahari dan juga suhu sekitar tanaman. Seperti halnya yang telah dilakukan UMKM Maestro Borneo Hidroponik Farm Palangka Raya bahwa dengan menanam hidroponik metode NFT (Nutrient Film Technique) dibutuhkan aliran air yang tetap terjaga, tujuannya untuk mengalirkan air nutrisi pada akar tanaman agar terus berjalan di setiap waktu. Dalam praktiknya, listrik PLN tentu sangat diperlukan guna untuk menghidupkan pompa air. Seiring dengan penggunaan listrik PLN, tentu beban listrik yang digunakan menjadi hal yang perlu diperhatikan, ditambah dengan kenaikan tarif PLN yang terjadi dan tentu akan lumayan memberikan dampak yang signifikan kepada pelaku usaha. Dalam kegiatan pengabdian ini, penulis akan melakukan upgrade sistem PLTS Atap yang sebelumnya pihak UMKM hanya menggunakan PLTS Atap sebagai energi alternatif. Artinya sistem PLTS Atap saat ini hanya akan digunakan jika terjadi pemadaman tiba-tiba listrik dari PLN. Berdasarkan permasalahan ini, solusi yang ditawarkan adalah dengan melakukan upgrade Sistem PLTS Atap Tipe Hybrid-Off Grid sebagai sumber energi utama dalam budidaya sistem hidroponi
Suppression of extraneous thermal noise in cavity optomechanics
Extraneous thermal motion can limit displacement sensitivity and radiation
pressure effects, such as optical cooling, in a cavity-optomechanical system.
Here we present an active noise suppression scheme and its experimental
implementation. The main challenge is to selectively sense and suppress
extraneous thermal noise without affecting motion of the oscillator. Our
solution is to monitor two modes of the optical cavity, each with different
sensitivity to the oscillator's motion but similar sensitivity to the
extraneous thermal motion. This information is used to imprint "anti-noise"
onto the frequency of the incident laser field. In our system, based on a
nano-mechanical membrane coupled to a Fabry-P\'{e}rot cavity, simulation and
experiment demonstrate that extraneous thermal noise can be selectively
suppressed and that the associated limit on optical cooling can be reduced.Comment: 27 pages, 14 figure
Universal three-state nematicity and magneto-optical Kerr effect in the charge density waves in AVSb (A=Cs, Rb, K)
The kagome lattice provides a fascinating playground to study geometrical
frustration, topology and strong correlations. The newly discovered kagome
metals AVSb (A=K, Rb, Cs) exhibit various interesting phenomena
including topological band structure and superconductivity. Nevertheless, the
nature of the symmetry breaking in the CDW phase is not yet clear, despite the
fact that it is crucial to understand whether the superconductivity is
unconventional. In this work, we perform scanning birefringence microscopy and
find that six-fold rotation symmetry is broken at the onset of the CDW
transition temperature in all three compounds. Spatial imaging and angle
dependence of the birefringence show a universal three nematic domains that are
120 to each other. We propose staggered CDW orders with a relative
phase shift between layers as a possibility to explain the three-state
nematicity in AVSb. We also perform magneto-optical Kerr effect and
circular dichroism measurements on all three compounds, and the onset of the
both signals is at the CDW transition temperature, indicating broken
time-reversal symmetry and the existence of the long-sought loop currents in
the CDW phase. Our work strongly constrains the nature of the CDWs and sheds
light on possible unconventional superconductivity in AVSb.Comment: 7 pages, 4 figures, submitted versio
Using e-learning to support international students' dissertation preparation
Purpose: A research paper on the design and implementation of an e-learning resource responding to the globalisation of education. The purpose of this paper is to focus on the challenges presented in learning and teaching on how to support international postgraduate (PG) students undertaking the specific task of a dissertation.
Design/methodology/approach: Using findings from 250 PG students, 40 supervisors and two module tutors the research identified the content and language issues faced by students and recognised the need to design an enabler supporting the latter as independent learners and the academic staff delivering support.
Findings: The e-learning tool provides an independent learning tool which addresses student concerns relating to the process and content of structuring a dissertation and the function of language. Initial responses have been positive from both staff and students in respect to providing a source of student support and feedback.
Originality/value: The research shows how the Dissertation Game Model (DGM), evolved into an e-learning resource supporting student understanding of the content, structure, planning and writing of a dissertation. The e-learning tool focuses on helping international students understand what the generic contents of each chapter of a dissertation should contain and supports them in engaging in research as a transferable skill
Psychometric evaluation of the Chinese version of the subjective happiness scale: Evidence from the Hong Kong FAMILY cohort
BACKGROUND: With China's rapid economic growth in the past few decades, there is currently an emerging focus on happiness. Cross-cultural validity studies have indicated that the four-item Subjective Happiness Scale (SHS) has high internal consistency and stable reliability. However, the psychometric characteristics of the SHS in broader Chinese community samples are unknown. PURPOSE: We evaluated the factor structure and psychometric properties of the SHS in the Hong Kong general population. METHODS: The Chinese SHS was derived using forward-backward translation. Of the Cantonese-speaking participants aged >/=15 years, 2,635 were randomly selected from the random sample component of the FAMILY Cohort, a territory-wide cohort study in Hong Kong. In addition to the SHS, a single-item overall happiness scale, the Patient Health Questionnaire-9 (PHQ-9), the Family Adaptation, Partnership, Growth, Affection, Resolve (APGAR) scale, and the Medical Outcomes Study 12-item short-form version 2 (SF-12) mental and physical health scales were administered. RESULTS: Exploratory and confirmatory factor analyses supported a single factor with high loadings for the four SHS items. Multiple group analyses indicated factor invariance across sex and age groups. Cronbach's alpha was 0.82, and 2-week test-retest reliability (n = 191) was 0.70. The SHS correlated significantly with single-item overall happiness (Spearman's rho [rho] = 0.57), Family APGAR (rho = 0.26), PHQ-9 (rho = -0.34), and mental health-related quality of life (rho = 0.40) but showed a lower correlation with physical health (rho = 0.15). A regression model that included the PHQ-9 and Family APGAR scores explained 37 % of the variance in SF-12 mental health scores; adding the SHS raised the variance explained to 41 %. CONCLUSIONS: Our results support the reliability and validity of the SHS as a relevant component in the measurement battery for mental well-being in a Chinese general population.published_or_final_versio
Precise targeted integration by a chimaeric transposase zinc-finger fusion protein
Transposons of the Tc1/mariner family have been used to integrate foreign DNA stably into the genome of a large variety of different cell types and organisms. Integration is at TA dinucleotides located essentially at random throughout the genome, potentially leading to insertional mutagenesis, inappropriate activation of nearby genes, or poor expression of the transgene. Here, we show that fusion of the zinc-finger DNA-binding domain of Zif268 to the C-terminus of ISY100 transposase leads to highly specific integration into TA dinucleotides positioned 6-17 bp to one side of a Zif268 binding site. We show that the specificity of targeting can be changed using Zif268 variants that bind to sequences from the HIV-1 promoter, and demonstrate a bacterial genetic screen that can be used to select for increased levels of targeted transposition. A TA dinucleotide flanked by two Zif268 binding sites was efficiently targeted by our transposase-Zif268 fusion, suggesting the possibility of designer ‘Z-transposases’ that could deliver transgenic cargoes to chosen genomic locations
Submesoscale eddies in the South China Sea
Submesoscale eddies are often seen in high‐resolution satellite‐derived ocean color images. To efficiently identify these eddies from surface chlorophyll data, here, we develop an automatic submesoscale eddy detection method and apply it to the South China Sea. The detected submesoscale eddies are found to have a radius of 13 ± 5 km and an aspect ratio of 0.5 ± 0.2, with a notable predominance of cyclones. Further investigation reveals that the surface structure of these eddies displays a unique “cat's‐eye” pattern, and the eddies become more circular with increasing eddy radius. Submesoscale eddies can strongly regulate surface chlorophyll via horizontal advection while they have less coherent signatures in sea surface temperature. These findings may help to improve submesoscale parameterizations in Earth system models
pH-responsive and antibacterial PANI-PEDOT:PSS fibres for wearable applications
With the emergence of wearable electronics for health and the prevalence of chronic wounds, there is demand for an effective wearable pH sensor. A simple method of solvent treating wet-spun poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) fibres proved effective in the development of highly conductive fibre substrates. With an optimised polyaniline coating, these fibres displayed a Nernstian response to changes in pH in the solid-state vs. a fabricated pseudoreference electrode across a wide pH range of 3.0 to 9.0. In addition, these biocompatible fibre electrodes displayed antibacterial properties. The fibre electrodes offer significant opportunities for future wearable textile-based sensors as well as the realisation of a real-time, on-body pH sensing device for monitoring skin and wound healing
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