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The conservation of quality factor under relativistic motion is applied to the superconducting cavities and the heartbeat of mammals. The total number of RF oscillation for superconducting cavities and that of heartbeat for mammals are conserved under relativistic motion. The frequency–energy relation is shown for the relativistic Doppler effect and energy conservation. The resonance frequency of the cavity decreases, and the decay time increases as the velocity and acceleration increase. The Q factor of the superconducting cavity is comparable to the total number of heartbeats of the mammal. The conservation of the Q factor for the heartbeat of the mammal, representing the total number of heartbeats, is also shown under relativistic motion. For mammals, the heart rate decreases, and the life expectancy increases as the velocity and acceleration increase.

The evaluation of half-wave resonator (HWR) cavity performance is presented in this study. We demonstrate the time-dependent characteristics of the fast cool-down process, as well as the RF conditioning and measurement procedures, including input power, reflected power, and transmitted power. Measurements encompass quality factor, resonance frequency, Lorentz force detuning (LFD), pressure sensitivity, and surface resistance for the HWR cavities. Furthermore, we determine Q slopes at temperatures of 4.2 K and 2 K for these cavities. Utilizing the Q slope data, we calculate the BCS resistance and estimate the bandgap for the Nb HWR cavity.

Physical phenomena at the zero temperature limit are studied in the field of accelerator physics. Experimental techniques have been developed to achieve temperatures approaching 0 K. As the universe expands, its background temperature continuously decreases. The energy density of thermal radiation is depicted as a function of temperature across different dimensions. In superconducting cavities, the surface resistance reduces to residual resistance at 0 K. The resistivity of various material types is presented in terms of temperature, and the thermal expansion of solid materials is also illustrated in terms of dimension. Blackbody radiation ceases at 0 K, along with thermal diffusion and thermal noise. However, quantum diffusion and zero-point noise persist at 0 K. With the exception of helium, all gases solidify at this temperature. Despite being at 0 K, zero-point energy still exists, and fundamental forces remain active. Moreover, black holes are expected to evaporate at 0 K, and the evaporation rate of black holes is calculated under these conditions.

Monolithic 3-D (M3D) integration has been spotlighted as an approach to overcome the limitation of classical scaling in integrated circuits (IC). However, the fabrication of the top-tier devices in M3D is challenging because of the limited maximum thermal budget during the integration process. In this work, a nanosecond annealing process using a pulsed green laser is introduced to fabricate the top-tier devices and minimize the thermal influence on the bottom-tier devices. With green laser, the average temperature gradient along the vertical direction within top-tier devices was reduced as much as 26%, compared to excimer laser. The pulsed green laser annealing effectively activated the dopant to form the source/drain of top-tier devices, which showed lower contact resistance ( ${R}_{c}$ ) by around 38% compared to the case of rapid thermal annealing (RTA) process. Furthermore, the nanosecond green laser annealing achieved a lower equivalent oxide thickness (EOT) and 63% reduction of interface trap density ( ${D}_{\text {it}}$ ) of high- ${K}$ gate dielectric in the top-tier MOS devices, leading to smaller subthreshold swing (SS) and enhanced effective mobility up to 13% and 29%, respectively, compared to the use of RTA.

We report the feasibility of ultralow- ${k}$ amorphous boron nitride ( $\alpha $ -BN) film as a new capping layer for copper (Cu) interconnects. $\alpha $ -BN thin films were successfully deposited using a plasma-enhanced chemical vapor deposition (PECVD) process. The CVD-grown $\alpha $ -BN showed a ${k}$ -value as low as 2.0 at 3 nm thickness, low leakage current density ( $\sim 7\times 10^{-{8}}$ A/cm2), and high breakdown field ( $\sim $ 8.8 MV/cm) comparable to a conventional SiN blocking layer. The $\alpha $ -BN has excellent thermal stability up to 1000 °C, implying that the film can be used not only for the back-end-of-line (BEOL) but also for the front-end-of-line (FEOL) processes. A 7-nm-thick $\alpha $ -BN film successfully blocked Cu diffusion at temperatures up to 500 °C. The $\alpha $ -BN film also showed excellent adhesion to Cu, with an adhesion energy of 2.90 ±0.51 J/ $\text{m}^{{2}}$ between $\alpha $ -BN and Cu. The COMSOL multiphysics simulation predicted that, compared to a conventional SiN capping layer, an $\alpha $ -BN capping layer would reduce interconnect RC delay by up to 17%. The $\alpha $ -BN was proven to be a promising new candidate for a capping layer to reduce RC delay in Cu interconnect systems.

Background: Although antiestrogens have been effective in preventing estrogen receptor (ER)-positive breast cancer, chemopreventive agents are still needed to prevent ER-negative breast cancer. Tyrosine kinase inhibitors are promising agents for the treatment and prevention of human cancers. ZD1839 (gefitinib or Iressa) is an orally active epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor that blocks signal transduction pathways in epithelial cells. We examined whether ZD1839 blocks signal transduction and prevents the development of ER-negative breast cancer. Methods: The ability of ZD1839 to block signal transduction in normal, immortalized, and malignant breast cells was assessed by western blotting with specific antibodies to detect phosphorylation of cytoplasmic signaling molecules. The effect of ZD1839 on growth of these breast cells was assessed with anchorage-dependent and anchorage-independent growth assays. Its effect on ER-negative mammary tumorigenesis was assessed in MMTV-erbB2 transgenic mice. All statistical tests were two-sided. Results: ZD1839 suppressed the phosphorylation of EGFR and mitogen-activated protein kinase in normal and malignant breast cells. ZD1839 treatment statistically significantly suppressed mammary tumorigenesis in MMTV-erbB2 transgenic mice; median time to tumor development was approximately 230 days in vehicle-treated mice and more than 310 days in mice treated with ZD1839 at 100 mg/kg (P

The unified current density for thermionic emission and field emission is derived in two-dimensional materials. Thermal radiation is investigated in two dimensions. The thermionic emission is studied in two dimensions and the field emission is also studied for two-dimensional materials. The unified theory of thermionic emission and field emission is studied in two-dimensional conductors. The two-dimensional current density is presented in terms of temperature and in terms of electric field for different work functions. The two-dimensional current density of graphene is expressed in terms of temperature and also in terms of electric field for different temperatures. Generalized three-dimensional current density is also derived and presented in terms of temperature and in terms of electric field for different work functions. The current densities of the thermionic emission in two dimensions and three dimensions are compared as a function of temperature.

•The South Korean government has established a holistic vision for smart farming•Smart farming solutions in the U.S. are discrete and driven mainly by private industry•Cultural and political differences shape alternate approaches to smart farming solutions•Frameworks for smart farming solutions could facilitate achievement of sustainable development goals

We report a theoretical investigation of field emission from metals in n-dimension. The field-emission current density is derived as a function of the electric field in one to three dimensions. Then, the generalized field-emission current density is calculated for arbitrary n dimensions, is shown as a function of electric field for different work functions of one-, two- and three-dimensional materials, and is expressed as a function of dimension for different work functions. These analyses reveal that the current density increases as the spatial dimension increases in the conductors and work function decreases. Our study on the generalized current density can be applied to material systems with high dimensions or fractional dimensions.

Although the Li metal has been gaining attention as a promising anode material for the next-generation high-energy-density rechargeable batteries owing to its high theoretical specific capacity (3860 mAh g–1), its practical use remains challenging owing to inherent issues related to Li nucleation and growth. This paper reports the fabrication of a lithiophilic multichannel layer (LML) that enables the simultaneous control of Li nucleation and growth in Li-metal batteries. The LML, composed of lithiophilic ceramic composite nanoparticles (Ag-plated Al2O3particles), is fabricated using the electroless plating method. This LML provides numerous channels for a uniform Li-ion diffusion on a nonwoven separator. Furthermore, the lithiophilic Ag on the Li metal anode surface facing the LML induces a low overpotential during Li nucleation, resulting in a dense Li deposition. The LML enables the LiNi0.8Co0.1Mn0.1O2|| Li cells to maintain a capacity higher than 75% after 100 cycles, even at high charge/discharge rates of 5.0 C at a cutoff voltage of 4.4 V, and achieve an ultrahigh energy density of 1164 Wh kg–1. These results demonstrate that the LML is a promising solution enabling the application of Li metal as an anode material in the next-generation Li-ion batteries.

Thermionic emission for quasi-free electron metals is investigated in arbitrary dimension. The thermionic emission for a constant temperature and work function is calculated for one, two and three dimensions. The generalized current density of the thermionic emission is calculated for arbitrary dimension. The current density is shown as a function of temperature for different work functions. The current density is also shown as a function of dimension for different temperatures and work functions.

The capillary rise phenomenon of the water in a cylindrical tube is investigated in arbitrary acceleration. The surface roughness of water comes from thermal energy. The critical radius of a water drop between surface tension and volume force is shown as a function of acceleration. The governing equation for capillary rise in a cylindrical tube is shown in terms of the radius, surface tension, contact angle, viscosity, and acceleration. The maximum height of the water is inversely proportional to the diameter of the cylindrical tube. The motion of the water’s height is shown as a function of the diameter of the cylindrical tube. The height of the water’s rise is also shown as a function of time for different accelerations.

The fabrication of the β= 0.12 half-wave resonator prototype at the Rare Isotope Science Project (RISP) is now complete, and the subsequent processing and the vertical test are expected to begin shortly. The details of the fabrication are reported in this paper. We describe the fabrication steps, together with the quality control effort, for the optimal performance of the cavity at the vertical test.

The design and the assembly of the quarter-wave resonator (QWR) and half-wave resonator (HWR) cryomodules for RAON are shown. The cryomodule is optimized for heat loads due to superfluid helium at 2 K, supercritical helium at 4.5 K and the thermal shield at 40 K. The cryomodule consists of a vacuum chamber, a magnetic shield, a thermal shield, a cryogenic pipe line and a support bar.

Food delivery from restaurants and fast food shops by motorbikes is one of the major modes of its distribution. We aim to investigate the environmental impact of food delivery process by motorbikes. The environmental impact was described from the viewpoint of waste gas emission and emission exergy. A university campus was selected as the test site. We extracted the number of food delivery, average fuel consumption and driving distance per motorbike by collecting data from restaurants. We did an experiment to find how much fuel is consumed if a driver does idling during delivery. The experiment gives us 20.8 ± 8.3 ml for 5 min idling. In cruising state there is a high value of CO2emission (~90% of total waste per year) into the environment mainly in September and December, although from exergy analysis CO contributes more to the exergy emission than CO2in most cases.

We report a coaxial fiber supercapacitor, which consists of carbon microfiber bundles coated with multiwalled carbon nanotubes as a core electrode and carbon nanofiber paper as an outer electrode. The ratio of electrode volumes was determined by a half-cell test of each electrode. The capacitance reached 6.3 mF cm–1(86.8 mF cm–2) at a core electrode diameter of 230 μm and the measured energy density was 0.7 μWh cm–1(9.8 μWh cm–2) at a power density of 13.7 μW cm–1(189.4 μW cm–2), which were much higher than the previous reports. The change in the cyclic voltammetry characteristics was negligible at 180° bending, with excellent cycling performance. The high capacitance, high energy density, and power density of the coaxial fiber supercapacitor are attributed to not only high effective surface area due to its coaxial structure and bundle of the core electrode, but also all-carbon materials electrodes which have high conductivity. Our coaxial fiber supercapacitor can promote the development of textile electronics in near future.

c-myc oncogene is implicated in tumorigenesis of many cancers, including breast cancer. Although c-myc is a well-known estrogen-induced gene, its promoter has no estrogen-response element, and the underlying mechanism by which estrogen induces its expression remains obscure. Recent genome-wide studies by us and others suggested that distant elements may mediate estrogen induction of gene expression. In this study, we investigated the molecular mechanism by which estrogen induces c-myc expression with a focus on these distal elements. Estrogen rapidly induced c-myc expression in estrogen receptor (ER)-positive breast cancer cells. Although estrogen had little effect on c-myc proximal promoter activity, it did stimulate the activity of a luciferase reporter containing a distal 67-kb enhancer. Estrogen induction of this luciferase reporter was dependent upon both a half-estrogen response element and an activator protein 1 (AP-1) site within this enhancer, which are conserved across 11 different mammalian species. Small interfering RNA experiments and chromatin immunoprecipitation assays demonstrated the necessity of ER and AP-1 cross talk for estrogen to induce c-myc expression. TAM67, the AP-1 dominant negative, partially inhibited estrogen induction of c-myc expression and suppressed estrogen-induced cell cycle progression. Together, these results demonstrate a novel pathway of estrogen regulation of gene expression by cooperation between ER and AP-1 at the distal enhancer element and that AP-1 is involved in estrogen induction of the c-myc oncogene. These results solve the long-standing question in the field of endocrinology of how estrogen induces c-myc expression.

There are two kinds of well-known electron emissions from metal: field and thermionic emission. For thermionic emission, electrons come out of a metal due to the thermal energy, whereas for field emission, electrons tunnel out of a metal through the strong electric field. In this study, the most general electron emission caused by the temperature and electric field with a free electron gas model was considered. The total current density of electron emission comes from the field emission effect, where the electron energy is lower than vacuum, and from the thermionic-emission effect, where the electron energy is higher than vacuum. The total current density of electron emission is shown as a function of the temperature for a constant electric field, and as a function of the electric field for a constant temperature.

A backlight unit for a 42-inch LCD TV was manufactured with red, green, and blue LED lamps. The luminous and light extraction efficiencies of the LED lamps were increased by improving their light reflection structures and thermal properties. The blue, green, and red LED lamps showed different luminous efficiencies as a function of the input current. Compared to the conventional red LED lamp, however, the developed red LED lamp showed very high luminous efficiency in a low drive current. Taking these luminous efficiencies into account, the fabricated backlight unit showed high energy efficiency, low power consumption, and a wide color gamut.

In this study, a very small LED packaging lead frame with a low thermal resistance was developed. The cost of the package process was reduced by the use of many small LED lamps, which increased the light emission efficiency. Compared to the large lead frame lamp, however, the optical property of the small LED packaging lead frame lamp was not sufficiently improved because its reflection structure was changed and its reflection area was reduced. The luminous efficiency of the LED lamp reaches 58 lm/W at the current density of 0.16 A/cm2. Using the LED lamps, 46-inch LCD BLU was manufactured. The BLU-made LED lamps have a low power consumption of 146 W and have a slim (10-mm-thick) BLU, keeping good uniformity in terms of brightness, and maintaining good thermal properties.

The ionization of a helium atom was investigated as a function of gas pressure, with the use of a tungsten tip. The tungsten tip, to which the external voltage was applied, was used to generate a constant electron current. The ionization current of helium gas was measured as a function of gas pressure. Effective ionization occurred in the pressure range of 0.5-20 torr when the distance between the field emission tip and the collector was 1 cm. The ionization current was linearly proportional to the voltage that was applied to the tungsten tip.

The transactivation of nuclear receptors is regulated by both ligand binding and phosphorylation. We previously showed that RARα (retinoic acid receptor α) phosphorylation by c-Jun N-terminal kinase contributes to retinoid resistance in a subset of NSCLC cells (non-small cell lung cancer cells), but the aetiology of this resistance in the remainder has not been fully elucidated [Srinivas, Juroske, Kalyankrishna, Cody, Price, Xu, Narayanan, Weigel and Kurie (2005) Mol. Cell. Biol. 25, 1054–1069]. In the present study, we report that Akt, which is constitutively activated in NSCLC cells, phosphorylates RARα and inhibits its transactivation. Biochemical and functional analyses showed that Akt interacts with RARα and phosphorylates the Ser96 residue of its DNA-binding domain. Mutation of Ser96 to alanine abrogated the suppressive effect of Akt. Overexpression of a dominant-negative form of Akt in an NSCLC cell line decreased RAR phosphorylation, increased RAR transactivation and enhanced the growth-inhibitory effects of an RAR ligand. The findings presented here show that Akt inhibits RAR transactivation and contributes to retinoid resistance in a subset of NSCLC cells.

Despite advances in treatment, breast cancer continues to be the second leading cause of cancer mortality in women. Statistics suggest that while focus on treatment should continue, chemopreventive approaches should also be pursued. Previous studies have demonstrated that naturally occurring retinoids such as 9-cisretinoic acid (9cRA) can prevent breast cancer in animal models. However, these studies have also shown that these compounds are too toxic for general use. Work from our laboratory showed that an RXR-selective retinoid LGD1069 prevented tumor development in animal models of cancer with reduced toxicity as compared to an RAR-selective retinoid TTNPB. In the present study, we investigated the mechanisms by which receptor-selective retinoids inhibit the growth of normal and malignant breast cells. Our results demonstrate that the synthetic retinoids tested are as effective as 9cRA in suppressing the growth of normal human mammary epithelial cells (HMECs) and estrogen receptor-positive (ER-positive) breast cancer cells. Although the receptor-selective retinoids induce minimal amounts of apoptosis in T47D breast cancer cells, the predominant factor that leads to growth arrest is G1 cell cycle blockade. Our data indicate that this blockade results from the downregulation of Cyclin D1 and Cyclin D3, which in turn causes Rb hypophosphorylation. Non-toxic retinoids that are potent inducers of cell cycle arrest may be particularly useful for the prevention of breast cancer.Despite advances in treatment, breast cancer continues to be the second leading cause of cancer mortality in women. Statistics suggest that while focus on treatment should continue, chemopreventive approaches should also be pursued. Previous studies have demonstrated that naturally occurring retinoids such as 9-cisretinoic acid (9cRA) can prevent breast cancer in animal models. However, these studies have also shown that these compounds are too toxic for general use. Work from our laboratory showed that an RXR-selective retinoid LGD1069 prevented tumor development in animal models of cancer with reduced toxicity as compared to an RAR-selective retinoid TTNPB. In the present study, we investigated the mechanisms by which receptor-selective retinoids inhibit the growth of normal and malignant breast cells. Our results demonstrate that the synthetic retinoids tested are as effective as 9cRA in suppressing the growth of normal human mammary epithelial cells (HMECs) and estrogen receptor-positive (ER-positive) breast cancer cells. Although the receptor-selective retinoids induce minimal amounts of apoptosis in T47D breast cancer cells, the predominant factor that leads to growth arrest is G1 cell cycle blockade. Our data indicate that this blockade results from the downregulation of Cyclin D1 and Cyclin D3, which in turn causes Rb hypophosphorylation. Non-toxic retinoids that are potent inducers of cell cycle arrest may be particularly useful for the prevention of breast cancer.

Abstract Multielectron bubbles (MEBs) in superfluid helium support a two-dimensional electron gas (2deg) on the surface of a sphere. In principle, electron densities can range from ~ 1010 to 1014/cm2. Wigner crystallization has been observed on a flat bulk surface of helium, but the maximum density of ~ 2 × 109 is insufficient to observe quantum melting. MEBs have a number of fascinating properties. They should not only allow observation of the Wigner lattice and quantum melting, but at very high densities a new type of electron localization into a lattice called the ripplopolaron lattice is predicted. We discuss a number of phenomena and experimental techniques aimed at long-time stabilization of MEBs.

In complex systems, synchronization plays a pivotal role underlying the coherent operation of various systems (networks) ranging from biology to technology. In a dynamic network, a link between nodes can be newly created implementing a new interaction in the network. Therefore, it is of great importance to understand how to enhance the synchronized state of a system especially when adding a new connection. This study investigates ways to enhance synchronization through optimal link addition, employing the Synchrony Alignment Function (SAF) and Adjusted Lyapunov Function (ALF) that assess the effects of new connections. By applying the ALF method to compare potential link additions, we identify two key factors that contribute to the effectiveness of link addition: the steady-state phase in the linearized dynamics, which we named the pseudo-steady-state phase, and the structural attributes of the network. By applying these methods across diverse network topologies, including Barabási–Albert, Erdős–Rényi, and Cayley tree models, we uncover the dominant role of the phase difference in promoting synchronization. This exploration offers new insights into the dynamics of network synchronization, highlighting the critical impact of specific factors on the efficacy of enhancing network coherence. Our findings also lay a foundation for further research into targeted strategies for network optimization. • When adding a new link to an oscillatory system, an effective strategy is necessary. • Phase difference and distance are the simple and crucial factors for link insertion. • The pseudo-phase difference is more effective than the actual phase differences. • Network distance plays a significant role only in the low link density cases. • The pseudo-phase can guide an optimal link addition ensuring the system's synchrony. [ABSTRACT FROM AUTHOR]

A dense fog consisting of superfluid 4He droplets can be generated in helium vapor up to a height of a few cm from the helium surface by driving a piezo transducer plate immersed under the liquid. The average droplet size is measured with a long-distance microscope and CCD camera, and ranges from about 100 μm at a drive frequency of 1 kHz to 10 μm at 100 kHz. The dependence of the droplet size on frequency is quite consistent with the capillary-wave dispersion relation of the helium surface, with the droplets ejected from the surface being about one wavelength in diameter. The initial vertical velocity of the droplets emerging from the surface is found to increase linearly with the driving voltage being applied to the piezo.

Effective frequency control in power grids has become increasingly important with the increasing demand for renewable energy sources. Here, we propose a novel strategy for resolving this challenge using graph convolutional proximal policy optimization (GC-PPO). The GC-PPO method can optimally determine how much power individual buses dispatch to reduce frequency fluctuations across a power grid. We demonstrate its efficacy in controlling disturbances by applying the GC-PPO to the power grid of the UK. The performance of GC-PPO is outstanding compared to the classical methods. This result highlights the promising role of GC-PPO in enhancing the stability and reliability of power systems by switching lines or decentralizing grid topology. • Power grids become more decentralized and vulnerable due to inertia-free generators. • Power generation fluctuates across various time scales and is subject to weather. • To ensure stability of the grid, a decentralized power dispatch strategy is demanded. • We develop an optimal power dispatch strategy using reinforcement learning. [ABSTRACT FROM AUTHOR]