During their evolution, short-period exoplanets may lose envelope mass through atmospheric escape owing to intense X-ray and extreme ultraviolet (XUV) radiation from their host stars. Roche-lobe ...overflow induced by orbital evolution or intense atmospheric escape can also contribute to mass loss. To study the effects of mass loss on inner planet populations, we calculate the evolution of hot Jupiters considering mass loss of their envelopes and thermal contraction. Mass loss is assumed to occur through XUV-driven atmospheric escape and the following Roche-lobe overflow. The runaway effect of mass loss results in a dichotomy of populations: hot Jupiters that retain their envelopes and super Earths whose envelopes are completely lost. Evolution primarily depends on the core masses of planets and only slightly on migration history. In hot Jupiters with small cores (Asymptotically = to10 Earth masses), runaway atmospheric escape followed by Roche-lobe overflow may create sub-Jupiter deserts, as observed in both mass and radius distributions of planetary populations. Comparing our results with formation scenarios and observed exoplanets populations, we propose that populations of closely orbiting exoplanets are formed by capturing planets at/inside the inner edges of protoplanetary disks and subsequent evaporation of sub-Jupiters.
We examined the excitations of planetesimals caused by the resonances of a giant planet in a protoplanetary gas disk. The highly excited planetesimals generate bow shocks, the mechanism of which ...results in chondrule formation, crystallization of silicate dust, and evaporation of icy planetesimals. The planetesimals beyond 2:1 resonance migrate owing to the gas drag and obtain the maximum eccentricity around 3:1 resonance, which is located at approximately half the planetary distance. The eccentricity depends on the parameters of the planetesimals and the Jovian planet, such as size and location, and the gas density of the disk. The maximum relative velocity of a 100 km sized planetesimal with respect to the gas disk reaches up to ∼12 km s−1 in the case of Jupiter owing to secular resonance, which occurs because of the disk's gravity. We find that if a Jovian-mass planet is located within 10 au, the planetesimals larger than 100 km gain sufficient velocity to cause the melting of chondrule precursors and crystallization of the silicate. The maximum velocity is higher for large planetesimals and eccentric planets. Planetesimals are trapped temporarily in the resonances and continue to have high speed over 1 Myr after the formation of a Jovian planet. This duration fits into the timescale of chondrule formation suggested by the isotopic data. The evaporation of icy planetesimals occurs when a Jovian planet is located within 15 au. This mechanism can be a new indicator of planet formation in exosystems if some molecules ejected from icy planetesimals are detected.
We made near-infrared multicolor imaging observations of a disk around Herbig Be star HD 100546 using Gemini/NICI. K (2.2 mum), H sub(2) O ice (3.06 mum), and L' (3.8 mum) disk images were obtained ...and we found a 3.1 mum absorption feature in the scattered light spectrum, likely due to water ice grains at the disk surface. We compared the observed depth of the ice absorption feature with the disk model based on Oka et al., including the water ice photodesorption effect by stellar UV photons. The observed absorption depth can be explained by both the disk models with and without the photodesorption effect within the measurement accuracy, but the model with photodesorption effects is slightly more favored, implying that the UV photons play an important role in the survival/destruction of ice grains at the Herbig Ae/Be disk surface. Further improvement to the accuracy of the observations of the water ice absorption depth is needed to constrain the disk models.
In humans, approximately 90% of saliva is secreted by the 3 major salivary glands: the parotid (PG), the submandibular (SMG), and the sublingual glands (SLG). Even though it is known that all 3 major ...salivary glands secrete saliva by a Cl--dependent mechanism, salivary secretion rates differ greatly among these glands. The goal of this study was to gain insight into the properties of the ion-transporting pathways in acinar cells that might account for the differences among the major salivary glands. Pilocarpine-induced saliva was simultaneously collected in vivo from the 3 major salivary glands of mice. When normalized by gland weight, the amount of saliva secreted by the PG was more than 2-fold larger than that obtained from the SMG and SLG. At the cellular level, carbachol induced an increase in the intracellular Ca2+ that was more than 2-fold larger in PG and SMG than in SLG acinar cells. Carbachol-stimulated Cl- efflux and the protein levels of the Ca2+-activated Cl- channel TMEM16A, the major apical Cl- efflux pathway in salivary acinar cells, were significantly greater in PG compared with SMG and SLG. In addition, we evaluated the transporter activity of the Na+-K+-2Cl- cotransporters (NKCC1) and anion exchangers (AE), the 2 primary basolateral Cl- uptake mechanisms in acinar cells. The SMG NKCC1 activity was about twice that of the PG and more than 12-fold greater than that of the SLG. AE activity was similar in PG and SLG, and both PG and SLG AE activity was about 2-fold larger than that of SMG. In summary, the salivation kinetics of the 3 major glands are distinct, and these differences can be explained by the unique functional properties of each gland related to Cl- movement, including the transporter activities of the Cl- uptake and efflux pathways, and intracellular Ca2+ mobilization.
Superconducting magnets for high-intensity accelerators and secondary particle sources are required to operate in the high radiation environment by beam collisions and beam losses. Neutron fluence in ...the high-luminosity LHC and the COMET experiment is expected to exceed 10 21 /m 2 . The stabilizer of superconductor is made of pure copper and/or aluminum, and it should degrade by such high radiation. A series of irradiation tests was done to evaluate degradation and recovery by measuring the electrical resistance. The effect of repetitive cycles of irradiation at cryogenic temperature and anneal at room temperature on stabilizer materials of copper and aluminum was measured using reactor neutrons at KUR. Also, pure metals were irradiated at cryogenic temperature by high-energy protons at J-PARC. This paper reviews the results of repetitive irradiation tests on copper and aluminum with reactor neutrons and accelerator protons.
Coffee berry borer (CBB),
, is a damaging insect pest of coffee worldwide. CBB has recently been introduced to Hawaii, so management techniques are still being developed for sustainable and ...cost-efficient approaches for the effective control of this pest. Field trials were conducted to evaluate the use of spinetoram on CBB infestation and bean damage compared to
and an untreated control. Initial CBB infestations were similar, and the treatments resulted in no detectable differences in subsequent new infestations. Damage to the coffee beans was reduced by both spinetoram and
compared to controls as the mortality of adult beetles resulting from the treatments prevented them from moving into the bean (C/D position) from the berry (A/B position). The mortality of adult beetles also prevented reproduction, subsequently reducing future CBB populations in the field. When applied to infested berries, spinetoram reduced live beetle populations in the A/B position by 73% and CBBs in the C/D position by 70% compared to the water control, whereas applications of
reduced beetles in the C/D position by 37% but had no effect on the live A/B population. An integrated pest management program is recommended for the effective control of CBBs, and the use of spinetoram applications when adult beetles are in the A/B position appears to have potential as another management tool.
A varistor is a non-linear <inline-formula><tex-math notation="LaTeX">V</tex-math></inline-formula>-<inline-formula><tex-math notation="LaTeX">I</tex-math></inline-formula> resistor and its feature ...helps to extract stored energy of the magnet quickly while suppressing the magnet voltage. High Energy Accelerator Research Organization (KEK) decided to install the varistor for the test facility in order to conduct quench training of a superconducting magnet safely. The new energy extraction (EE) system consists of varistors made of silicon carbide (SiC) disks and is designed to extract energy up to 5 MJ. These varistors were installed prior to the test of the HL-LHC D1 magnet in 2023 and validated throughout the power test. A current imbalance and turn-on time (<inline-formula><tex-math notation="LaTeX">t_\text{ON}</tex-math></inline-formula>) among the varistor units, which could affect performance of the magnet protection, are monitored and measured to be within <inline-formula><tex-math notation="LaTeX">\pm \text{4}\%</tex-math></inline-formula> and 300 µs, respectively.
Listeria monocytogenes and Escherichia coli O157:H7 are common causes of foodborne illness worldwide. Ohelo berry (Vaccinium calycinum) juice was found to possess inhibitory activity against L. ...monocytogenes. This study aimed to determine which constituents of ohelo berry have the most potent antimicrobial effects. The crude extract of ohelo berry was separated into sugar plus organic acids (F1), non-anthocyanin phenolics (F2), and anthocyanins (F3). The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the fractions were determined against L. monocytogenes and E. coli O157:H7. The results demonstrated that F3 contained the highest concentrations of total phenolics and anthocyanins. All fractions caused a significant growth reduction in two bacteria compared to controls. F1 at native pH had the same MIC (1.39/0.36 Bx/acid) and MBC (5.55/1.06 Bx/acid) against the two bacteria, while neutralized F1 did not inhibit the growth of either pathogen. The MIC of F3 against L. monocytogenes was 13.69 mg/L cyanidin-3-glucoside equivalent, which was not affected by neutralization. Besides, L. monocytogenes was more sensitive than E. coli O157:H7 to all fractions. These findings suggest that both phenolics and organic acids contribute to the antimicrobial properties of ohelo berry, which have the potential to be used as natural food preservatives.
We report the test results of the first series beam separation dipole, MBXF1, for the HL-LHC project. The magnet has a full length of 7 m and is designed to generate a field integral of 35 T ...<inline-formula><tex-math notation="LaTeX">\cdot</tex-math></inline-formula> m at a nominal operating current (<inline-formula><tex-math notation="LaTeX">I_\text{nominal}</tex-math></inline-formula>) of 12.11 kA. The cold test is performed at the test facility in High Energy Accelerator Research Organization (KEK) using a 9-m deep vertical cryostat. The test consists of two test cycles with one thermal cycle. In each of the test cycles MBXF1 is energized in superfluid helium at 1.9 K and subjected to a series of quench training and magnetic field evaluation. The test shows that the magnet has a good training performance as it reaches <inline-formula><tex-math notation="LaTeX">I_\text{nominal}</tex-math></inline-formula> with two quenches and an ultimate operating current (<inline-formula><tex-math notation="LaTeX">I_\text{ultimate}</tex-math></inline-formula>) of 13.231 kA with seven quenches. Furthermore we observe no quench during the training of the second test cycle, indicating MBXF1 has a good training memory. Magnetic measurements of MBXF1 show that the discrepancy between the measured and computed harmonics at the magnetic center is 3.9 units for normal sextupole and less than 0.5 units for the other allowed-normal multipoles. Finally sextupole integral (<inline-formula><tex-math notation="LaTeX">\bar{b}_{3}</tex-math></inline-formula>) and decapole integral (<inline-formula><tex-math notation="LaTeX">\bar{b}_{5}</tex-math></inline-formula>), which are major systematic field errors in MBXF, respectively are estimated to be 2.0 units and 1.7 units for an actual environmental condition with ferromagnetic materials in the LHC accelerator tunnel.
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