Theνe − e − elastic scattering cross-section was measured with a CsI(Tl) scintillating crystal array having a total mass of 187 kg. The detector was exposed to an average reactorνe flux of 6.4 × 10 12 cm −2 s −1 at the Kuo-Sheng Nuclear Power Station. The experimental design, conceptual merits, detector hardware, data analysis and background understanding of the experiment are presented. Using 29882/7369 kg-days of Reactor ON/OFF data, the Standard Model (SM) electroweak interaction was probed at the squared 4-momentum transfer range of Q 2 ∼ 3 × 10 −6 GeV 2 . The ratio of experimental to SM cross-sections of ξ = [1.08 ± 0.21(stat) ± 0.16(sys)] was measured. Constraints on the electroweak parameters (gV , gA) were placed, corresponding to a weak mixing angle measurement of sin 2 θW = 0.251 ± 0.031(stat ) ± 0.024(sys ). Destructive interference in the SMνe−e process was verified. Bounds on anomalous neutrino electromagnetic properties were placed: neutrino magnetic moment at µν e < 2.2 × 10 −10 µB and the neutrino charge radius at −2.1 × 10 −32 cm 2 < r 2 νe < 3.3 × 10 −32 cm 2 , both at 90% confidence level.

The aim of this study was to evaluate the changes in the prevalence of myopia in Taiwanese schoolchildren over the past few decades and to analyze the risk factors for myopia.Design: Analysis of 8 consecutive population-based myopia surveys conducted from 1983 through 2017.Participants: An average of 8917 (5019e11 656) schoolchildren 3 to 18 years of age were selected using stratified systematic cluster sampling or by probability proportional to size sampling.Methods: All participants underwent complete ophthalmic evaluations. Three drops of 0.5% tropicamide were used to obtain the cycloplegic refractive status of each participant. Questionnaires were used to acquire participant data from the 1995, 2005, 2010, and 2016 surveys.Main Outcome Measures: Prevalence of myopia (spherical equivalence of À0.25 diopter [D]) and high myopia ( À6.0 D) was assessed. Multivariate analyses of risk factors were conducted.Results: The prevalence of myopia among all age groups increased steadily. From 1983 through 2017, the weighted prevalence increased from 5.37% (95% confidence interval [CI], 3.50%e7.23%) to 25.41% (95% CI, 21.27%e29.55%) for 7-year-olds (P ¼ 0.001 for trend) and from 30.66% (95% CI, 26.89%e34.43%) to 76.67% (95% CI, 72.94%e80.40%) for 12-year-olds (P ¼ 0.001 for trend). The prevalence of high myopia also increased from 1.39% (95% CI, 0.43%e2.35%) to 4.26% (95% CI, 3.35%e5.17%) for 12-year-olds (P ¼ 0.008 for trend) and from 4.37% (95% CI, 2.91%e5.82%) to 15.36% (95% CI, 13.78%e16.94%) for 15-year-olds (P ¼ 0.039 for trend). In both the 2005 and 2016 survey samples, children who spent less than 180 minutes daily on near-work activities showed significantly lower risks for myopia developing (<60 minutes: odds ratio [OR], 0.48 and 0.56; 60e180 minutes: OR, 0.69 and 0.67). In the 2016 survey, spending more than 60 minutes daily on electronic devices was associated significantly with both myopia and high myopia (OR, 2.43 and 2.31).Conclusions: The prevalence of myopia among schoolchildren increased rapidly from 1983 through 2017 in Taiwan. The major risk factors are older age and time spent on near-work activities. Use of electronic devices increased the amount of time spent on near-work and may increase the risk of developing myopia.

Germanium ionization detectors with sensitivities as low as 100 eVee (electron-equivalent energy) open new windows for studies on neutrino and dark matter physics. The relevant physics subjects are summarized. The detectors have to measure physics signals whose amplitude is comparable to that of pedestal electronic noise. To fully exploit this new detector technique, various experimental issues including quenching factors, energy reconstruction and calibration, signal triggering and selection as well as evaluation of their associated efficiencies have to be attended. The efforts and results of a research program to address these challenges are presented.

An energy threshold of (220±10) eV was achieved at an efficiency of 50% with a four-channel ultra-low-energy germanium detector each with an active mass of 5 g. This provides a unique probe to WIMP dark matter with mass below 10 GeV. With a data acquisition live time of 0.338 kg-day at the Kuo-Sheng Laboratory, constraints on WIMPs in the galactic halo were derived. The limits improve over previous results on both spin-independent WIMP-nucleon and spin-dependent WIMPneutron cross-sections for WIMP mass between 3−6 GeV. Sensitivities for full-scale experiments are projected. This detector technique makes the unexplored sub-keV energy window accessible for new neutrino and dark matter experiments.PACS numbers: 95.35.+d, 98.70.Vc There is compelling evidence from cosmological and astrophysical observations that about one quarter of the energy density of the universe can be attributed to Cold Dark Matter(CDM), whose nature and properties are still unknown [1]. Weakly Interacting Massive Particles (WIMP, denoted by χ) are the leading candidates for CDM. There are intense experimental efforts[2] to look for WIMPs through direct detection of nuclear recoils in χN→χN elastic scattering or in the studies of the possible products through χχ annihilations. The Kuo-Sheng(KS) Laboratory[12] is located at 28 m from a 2.9 GW reactor core with an overburden of about 30 meter-water-equivalence. Limits on neutrino magnetic moments(µ ν )[13] with a 1.06-kg germanium detector(HPGe) at a threshold of 5 keV were reported [14]. These data also allowed the studies of reactor electron neutrinos [15] and reactor axions [16]. A background level of ∼ 1 event kg −1 keV −1 day −1 (cpkkd) at 20 keV, comparable with those of underground CDM experiments, was achieved. The current goal is to develop detectors with kg-scale target mass, 100 eV-range threshold and lowbackground specifications for the studies of WIMPs, µ ν and neutrino-nucleus coherent scatterings [17].Ultra-low-energy germanium detectors(ULEGe) is a matured technique for sub-keV soft X-rays measurements. They typically have modular mass of 5−10 g while detector arrays of up to 30 elements have been constructed. Compared with Al 2 O 3 , Ge provides enhancement in χN spin-independent couplings(σ SI χN ) due to the A 2 dependence [1,18], where A is the mass number of the target isotopes. The isotope 73 Ge (natural isotopic abundance of 7.73%) comprises an unpaired neutron such that it can provide additional probe to the spin-dependent couplings of WIMPs with the neutrons(σ SD χn ). The nuclear recoils from χN interactions in ULEGe only give rise to ∼20% of the observable ionizations compared with electron recoils at the same energy. The suppression ratio is called the quenching factor(QF) [19]. For clarity, all ULEGe measurements discussed hereafter in this article are electron-equivalent-energy, unless otherwise stated.The ULEGe array consists of 4-element each having an active mass of 5 g [20]. Standard ultra-low-background specifications were adopted in its construction and ch...

Neutrino-electron scatterings are purely leptonic processes with robust Standard Model (SM) predictions. Their measurements can therefore provide constraints to physics beyond SM. Thē νe − e data taken at the Kuo-Sheng Reactor Neutrino Laboratory were used to probe two scenarios: Non-Standard Neutrino Interactions (NSI) and Unparticle Physics. New constraints were placed to the NSI parameters (ε eL ee ,ε eR ee ), (ε eL eµ ,ε eR eµ ) and (ε eL eτ ,ε eR eτ ) for the Non-Universal and Flavor-Changing channels, respectively, as well as to the coupling constants for scalar (λ0) and vector (λ1) unparticles to the neutrinos and electrons.

In LMH secondary to ERM with significant visual decrease, ERM and ILM peeling may improve BCVA. Postoperative gas tamponade is associated with better restoration of macular configuration. Final BCVA is related to an intact photoreceptor IS-OS junction rather than to the normalization of the macular contour.

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