Neural-network Kohn-Sham exchange-correlation potential and its out-of-training transferability

We incorporate in the Kohn-Sham self consistent equation a trained neural-network projection from the charge density distribution to the Hartree-exchange-correlation potential $n \rightarrow V_{\rm Hxc}$ for possible numerical approach to the exact Kohn-Sham scheme. The potential trained through a newly developed scheme enables us to evaluate the total energy without explicitly treating the formula of the exchange-correlation energy. With a case study of a simple model we show that the well-trained neural-network $V_{\rm Hxc}$ achieves accuracy for the charge density and total energy out of the model parameter range used for the training, indicating that the property of the elusive ideal functional form of $V_{\rm Hxc}$ can approximately be encapsulated by the machine-learning construction. We also exemplify a factor that crucially limits the transferability--the boundary in the model parameter space where the number of the one-particle bound states changes--and see that this is cured by setting the training parameter range across that boundary. The training scheme and insights from the model study apply to more general systems, opening a novel path to numerically efficient Kohn-Sham potential.Comment: 7 pages, 6 figure

Short-term intake of a Japanese-style healthy lunch menu contributes to prevention and/or improvement in metabolic syndrome among middle-aged men: a non-randomized controlled trial

BACKGROUND: Metabolic syndrome is now widely appreciated as a cluster of metabolic abnormalities such as visceral obesity, hypertension, hyperglycemia and dyslipidemia. To date, incidence of metabolic syndrome is continuously increasing worldwide. In addition, low vegetable consumption has recently become a serious issue in Japan. Furthermore, Japan is facing a shortfall in places offering food that can help prevent metabolic syndrome in the first place. Our study is designed to influence these developments. We conducted a non-randomized controlled trial by offering a Japanese-style healthy lunch menu to middle-aged men in a workplace cafeteria. This menu was designed to prevent and reduce metabolic syndrome. METHODS: This intervention study took the form of a non-randomized controlled trial. Participants chose the control or intervention group. The control group consumed their habitual lunches without restriction and only nutrient contents were assessed. The intervention group received a Japanese-style healthy lunch at a workplace cafeteria for 3 months. The participants worked in offices at a city hall and mostly had low levels of physical activity. Data of 35 males (control group: 7 males, intervention group: 28 males, mean age: 47.2 ± 7.9 years) were collected and analyzed. RESULTS: We obtained an effective outcome by demonstrating that ongoing intake of a Japanese-style healthy lunch decreased blood pressure and serum lipids and increased plasma ghrelin levels. The results grew more pronounced as intake of Japanese-style healthy lunches increased in frequency. CONCLUSIONS: This study presents new empirical data as a result of an original intervention program undertaken in Japan. A Japanese-style healthy lunch menu containing many vegetables consumed can help prevent and/or improve metabolic syndrome

Nonclasscial interference between independent intrinsically pure single photons at telecom wavelength

We demonstrate a Hong-Ou-Mandel interference between two independent, intrinsically pure, heralded single photons from spontaneous parametric down conversion (SPDC) at telecom wavelength. A visibility of $85.5\pm8.3$ was achieved without using any bandpass filter. Thanks to the group-velocity-matched SPDC and superconducting nanowire single photon detectors (SNSPDs), the 4-fold coincidence counts are one order higher than that in the previous experiments. The combination of bright single photon sources and SNSPDs is a crucial step for future practical quantum info-communication systems at telecom wavelength.Comment: 4 pages, 5 figure

Detection-dependent six-photon NOON state interference

NOON state interference (NOON-SI) is a powerful tool to improve the phase sensing precision, and can play an important role in quantum sensing and quantum imaging. However, most of the previous NOON-SI experiments only investigated the center part of the interference pattern, while the full range of the NOON-SI pattern has not yet been well explored.In this Letter, we experimentally and theoretically demonstrate up to six-photon NOON-SI and study the properties of the interference patterns over the full range.The multi-photons were generated at a wavelength of 1584 nm from a PPKTP crystal in a parametric down conversion process.It was found that the shape, the coherence time and the visibility of the interference patterns were strongly dependent on the detection schemes.This experiment can be used for applications which are based on the envelope of the NOON-SI pattern, such as quantum spectroscopy and quantum metrology.Comment: 5 pages, 3 figure

Efficient generation of twin photons at telecom wavelengths with 10 GHz repetition-rate tunable comb laser

Efficient generation and detection of indistinguishable twin photons are at the core of quantum information and communications technology (Q-ICT). These photons are conventionally generated by spontaneous parametric down conversion (SPDC), which is a probabilistic process, and hence occurs at a limited rate, which restricts wider applications of Q-ICT. To increase the rate, one had to excite SPDC by higher pump power, while it inevitably produced more unwanted multi-photon components, harmfully degrading quantum interference visibility.Here we solve this problem by using recently developed 10 GHz repetition-rate-tunable comb laser, combined with a group-velocity-matched nonlinear crystal, and superconducting nanowire single photon detectors. They operate at telecom wavelengths more efficiently with less noises than conventional schemes, those typically operate at visible and near infrared wavelengths generated by a 76 MHz Ti Sapphire laser and detected by Si detectors. We could show high interference visibilities, which are free from the pump-power induced degradation. Our laser, nonlinear crystal, and detectors constitute a powerful tool box, which will pave a way to implementing quantum photonics circuits with variety of good and low-cost telecom components, and will eventually realize scalable Q-ICT in optical infra-structures.Comment: 10 pages, 10 figure

Study on relation between spatial distribution and release rate of hydrophobic compounds incorporated in polymer micelles with anomalous small angle X-ray scattering

Amphiphilic block copolymers in aqueous solution undergo self-assembly into polymer micelles composed of hydrophobic core and hydrophilic shell. The polymer micelles can solubilize hydrophobic compounds in aqueous solution by incorporating them in the hydrophobic core. Therefore, they have been expected to be a drug career in drug delivery system (DDS). In DDS, controlling of the drug release behavior and retention stability are critical issues. However, tuning release rate and stability of retention of drug molecules is significantly difficult. Since the hydrophobic molecules must pass through the hydrophobic cores and hydrated corona layers to go out the polymer micelles, their release properties should strongly depend on spatial distribution of drug molecules in polymer micelles. Therefore, to elucidate the relation between spatial distribution of drug molecules and release properties of drug molecules is of significant importance to design a novel DDS. Thus, the aim of this study is to clarify the relation between spatial distribution of hydrophobic compounds in polymer micelles and their release and retention property. Poly(methyl methacrylate)-block-poly(N,N-(dimethylamino)ethyl methacrylate) (Poly-1) as amphiphilic block copolymer was synthesized by reversible addition-fragmentation radical polymerization. The weight- and number-average molecular weights of the resulting Poly-1 were 1.6104 g mol-1 and 1.9104 g mol-1, respectively. Three kinds of compounds (9-bromofluorene (BrF), 4-bromobenzyl alcohol (BrBzOH), 4-bromophenol (BrPh)) were employed as bromine-labeled hydrophobic compounds. Poly-1 and a hydrophobic compound were mixed at 10 wt% of a hydrophobic compound against Poly-1. Please click Additional Files below to see the full abstract