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We present a new global survey of the purest anorthosite (PAN) rock using the Spectral Profiler onboard Kaguya. We found that PAN rocks are widely distributed over the Moon, including the Feldspathic Highland Terrain and the south and north polar regions. All PAN sites are associated with huge impact structures with diameters larger than 100 km. Based on the global distributions of PAN and olivine‐rich sites, we propose the existence of a massive PAN layer with a thickness of ∼50 km below an uppermost mafic‐rich mixed layer with a thickness of ∼10 km. Below the PAN layer, a lower crustal layer with olivine‐rich materials may be present on the nearside, but not on the far side of the Moon. The existence of a PAN layer with a thickness of ∼50 km suggests an Al2O3 abundance of 33 to 34 wt.% in the lunar crust, which is higher than previous estimates of <32 wt.%. Our data indicate the massive production event of PAN during the early stage of the formation of the Moon, supporting the lunar magma ocean scenario. Key Points The existence of a massive layer of pure anorthosite on the Moon Massive production of pure anorthosite produced during the lunar magma ocean Dichotomy of lunar lower crust

Underwater disturbances are the largest error source in Global Navigation Satellite System ‐ Acoustic ranging combination technique (GNSS‐A) seafloor geodetic observation. In particular, the gradient of sound speed structure (SSS) directly affects the horizontal accuracy and needs to be examined. Previous studies have not investigated its temporal change component. In this paper, we verified the assumption that the underwater gradient structure does not change significantly during GNSS‐A observation for several hours through applying a modified version of an analysis software called GARPOS to actual data of SGO‐A (provided by Japan Coast Guard). Obtained results suggested that this assumption holds at many observation data, and the positioning accuracy becomes better. Some non‐improved observation epochs were speculated to be accompanied by structure changes for which this assumption was not valid. It is suggested that the SSS change during observation will be an important research topic in GNSS‐A. Plain Language Summary Global Navigation Satellite System ‐ Acoustic ranging combination technique (GNSS‐A) is a seafloor geodetic observation method that determines the seafloor position by combining GNSS and acoustic ranging with centimeter‐scale accuracy. The biggest error in GNSS‐A is not the high‐rate (>1 Hz) GNSS noise, but the kilometer‐scale underwater disturbances. Previous studies have showed that the gradient of the sound speed structure strongly affects the positioning accuracy, but its time stability has not been verified. This paper has verified the assumption that the underwater structure does not change significantly during several hours in GNSS‐A observation and only the intensity of the gradient may change. Incorporating this assumption into the analysis method improved the variation of the GNSS‐A time‐series. Thus, the kilometer‐scale underwater structure was found to be generally time‐stable for components that affect GNSS‐A. This leads new research theme of GNSS‐A seafloor geodesy and GNSS‐A oceanography. Key Points We verified the assumption that the gradient of sound speed structure (SSS) affecting Global Navigation Satellite System ‐ Acoustic ranging combination technique (GNSS‐A) does not change during a given measurement epoch Incorporating this assumption into the determination of seafloor position reduced the variation in the GNSS‐A time‐series The results suggest that perceived changes in SSS are in fact unmodeled errors in acoustic measurements

Yuya Yokota, Yuki Otsuka, Fumio OtsukaDepartment of General Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, 700-8558, JapanCorrespondence: Yuki Otsuka, Department of General Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama, 700-8558, Japan, Tel +81-86-235-7342, Fax +81-86-235-7345, Email [email protected]View the original paper by Dr Hirata and colleaguesA Response to Letter has been published for this article.

Japanese Hayabusa2 spacecraft has successfully carried out an impact experiment using a small carry-on impactor (SCI) on an asteroid (162173) Ryugu. We examine the size distribution of particles inside and outside an artificial impact crater (the SCI crater) based on the images taken by the optical navigation camera onboard the Hayabusa2 spacecraft. The circumferential variation in particle size distribution inside the SCI crater is recognized and we interpret that major circumferential variation is caused by the large boulders inside the SCI crater that existed prior to the impact. The size distribution inside the SCI crater also shows that the subsurface layer beneath the SCI impact site had a large number of particles with a characteristic size of – 9 cm, which is consistent with the previous evaluations. On the other hand, the size distribution outside the SCI crater exhibits the radial variation, implying that the deposition of ejecta from the SCI crater is involved. The slope of the size distribution outside the crater at small sizes differs from the slope of the size distribution on the surface of Ryugu by approximately 1 or slightly less. This is consistent with the claim that some particles are buried in fine particles of the subsurface origin included in ejecta from the SCI crater. Thus, the particle size distributions inside and outside the SCI crater reveal that the subsurface layer beneath the SCI impact site is rich in fine particles with – 9 cm in size while the particles on the surface have a size distribution of a power-law form with shallower slopes at small sizes due to the deposition of fine ejecta from the subsurface layer. Finally, we discuss a process responsible for this difference in particle size distribution between the surface and the subsurface layers. The occurrence of segregation in the gravitational flow of particles on the surface of Ryugu is plausible.

The Global Navigation Satellite System—Acoustic combination (GNSS‐A) is used to observe seafloor crustal deformation by determining the global position of the seafloor with GNSS positioning and acoustic ranging between a sea surface platform and a transponder station located on the seafloor. However, GNSS‐A observations are currently conducted mainly by vessels, and economic and physical constraints limit the ability to improve the frequency and real‐time nature of observations. Therefore, unmanned arial vehicle (UAV) ‐based GNSS‐A observation has been proposed. In this study, we constructed a GNSS‐A system based on a seaplane‐type UAV capable of centimeter‐level measurements and evaluated its seafloor positioning performance. An experiment in a tank showed that the system has an acoustic ranging accuracy of less than 2.1 cm, and allowed us to evaluate the previously unreported fractional wavelength instrumental biases. UAV‐based GNSS‐A tests were conducted using the constructed system at an actual GNSS‐A site. Under optimal sea conditions devoid of significant waves or wind, the observation result suggested that seafloor positioning could be achieved with a horizontal RMS of approximately 1–2 cm—comparable to that of vessel‐based systems. Thus, we established the foundations for practical UAV observation technology for the operation of high‐frequency observations and emergency observations for detecting postseismic deformation. It has also become possible to verify instrument bias in a vessel‐based system. Key Points We constructed a centimeter‐level seafloor geodetic observation system using a seaplane‐type drone and evaluated its performance The preliminary and at‐sea trial tests demonstrated the precision of the constructed unmanned arial vehicle observation technology Building a system that does not need a ship enables high‐frequency observations and is also effective in verifying accuracy

Species generalization in the profound, modality-specific effects of Hedgehog pathway inhibition (HPI) in taste organ homeostasis and sensation is shown. With the HPI, cancer drug sonidegib, we demonstrate that the rat taste system, in addition to mouse, is regulated by Hedgehog signaling. After sonidegib treatment for 16–36 days in rat, there is loss of taste buds (TB) in soft palate, in fungiform (FP) and circumvallate papillae (CV), and elimination of taste responses from chorda tympani and glossopharyngeal nerves. The retained innervation in FP and CV during HPI cannot sustain TB. Responses to tactile stimuli are not altered, and temperature responses are reduced only after 28 days treatment, demonstrating modality-specific effects. Rat FP and neural effects are similar to those in mouse whereas TB and neural response effects from the rat CV are much more severe. When recovery is introduced in mouse after prolonged, 48 days HPI, the TB in CV are restored whereas those in FP are not. Overall, Hedgehog signaling regulation is shown to generalize to the rat taste system, and the modality-specific controls in taste organ sensation are affirmed. The reported, debilitating taste disturbances in patients who use HPI drugs can be better understood based on these data.

Leptoglossus zonatus is a polyphagous pest found throughout much of the Western Hemisphere. In California, L. zonatus attacks almond, pistachio, pomegranate, and walnut crops, but the seasonal use of and economic damage to these crops varies. To better understand the seasonal changes of L. zonatus populations and to improve monitoring programs in California’s San Joaquin Valley, we caged overwintering adult males and females and then followed the resulting population dynamics over a one-year period. There were three generations over the one-year period, although eggs, nymphs, and adults overlapped among successive generations. From an initial 75 overwintering adult females, there were 1214 egg strands, 16,692 nymphs, and 4900 adults recorded during the one-year period. Depending on the generation, the number of nymphs per egg strand ranged from 11.3 to 14.3; the sex ratio was close to 1:1 with the exception of one female-biased cage; and nymph mortality ranged from 22.0% to 39.5%. Adult females isolated from each generation produced 2.4–5.1 egg strands per female that totaled 41.7–61.7 eggs per female with a 67.1–86.8% successful hatch rate. We find that the adult is the overwintering stage, as more adults (without food provisions) survived the winter compared to medium-sized or large-sized nymphs provided with both food and water. The results are discussed with respect to the development of L. zonatus control and monitoring programs for California’s multi-billion-dollar (US) nut crops.

The vine mealybug (VMB), Planococcus ficus (Hemiptera: Pseudococcidae), is a key insect pest of vineyards, and improvements in sustainable control of this pest are needed to meet increasing consumer demand for organically farmed products. One promising option is mating disruption. In a series of experiments conducted from 2004 to 2007, we tested the effects of mating disruption on trap captures of Pl. ficus males in pheromone-baited traps, on Pl. ficus numbers and age structure on vines, and on damage to grape clusters. From 2004 to 2005, the effects of dispenser load (mg active ingredient per dispenser) were also assessed, and dispensers were compared to a flowable formulation. Across all trials, mating disruption consistently reduced pheromone trap captures and often reduced mealybug numbers on vines and/or crop damage, regardless of the pheromone dose that was applied. Reductions in Pl. ficus densities in mating disruption plots were not accompanied by clear effects on mealybug population age structure; however, production of non-viable ovisacs by unmated females may have obscured differences in proportional representation of ovisacs. Pheromone trap captures were never lowered to zero (often called trap shut down), possibly because trials were conducted in vineyards with unusually high Pl. ficus densities. Trap-capture patterns in both treated and control plots commonly began low in April–May, increased in mid-July or August, and often decreased in September–October when post-harvest insecticides were applied. During the four-year trial, the release rate from plastic sachet dispensers was improved by industry cooperators as pheromone was released too quickly (2004) or not completely released during the season (2005–2006). The flowable formulation performed slightly better than dispensers at the same application dose. Results over all years suggest season-long coverage or late-season coverage may be as or more important than dose per hectare. Development of a dispenser with optimized season-long pheromone emission or targeted seasonal periods should be a future goal.

Rendezvous of the Japanese spacecraft Hayabusa with the near-Earth asteroid 25143 Itokawa took place during the interval September through November 2005. The onboard camera imaged the solid surface of this tiny asteroid (535 meters by 294 meters by 209 meters) with a spatial resolution of 70 centimeters per pixel, revealing diverse surface morphologies. Unlike previously explored asteroids, the surface of Itokawa reveals both rough and smooth terrains. Craters generally show unclear morphologies. Numerous boulders on Itokawa's surface suggest a rubble-pile structure.

1. Mechanisms responsible for the success or failure of agricultural diversification are often unknown. Most studies of arthropod pest management focus on enhancing natural enemy effectiveness. However, non-crop plants can also change crop host quality by reducing or adding soil nutrients or water, and therefore improve or hamper pest suppression. Native perennial ground covers may provide food or habitat to natural enemies and, in terms of competition for soil nutrients or water, be more compatible with crop management than exotic annuals. 2. We conducted a 3-year vineyard study to examine the impacts of native perennial grasses on pests, natural enemies, crop plant condition and soil properties. We included three ground cover treatments: bare soil with a grower standard drip irrigation; native grasses with drip irrigation; and native grasses with drip irrigation as well as an additional flood irrigation to keep the grasses green and growing during the season. 3. Numbers of leafhopper pests Erythroneura spp. decreased in both native grass treatments, where parasitism rates were higher. Vine petiole nitrate levels were lower in grass treatments, indicating competition for soil nitrogen, which is most often considered to be detrimental. Berry weight was higher in the irrigated treatment but did not differ between the bare soil and non-irrigated grass treatment. Grape °Brix was similar in the bare soil and native grass treatments, suggesting native grasses did not compromise grape quality. In fact, leaf water stress was lower and soil moisture higher not only in the irrigated grass treatment but, at times, in the non-irrigated grass treatment, compared with the bare soil treatment. 4. synthesis and applications. Our work shows that native grasses contribute to a reduction in vineyard leafhopper pests by reducing host quality through competition for soil nitrogen and providing food resources and/or habitat for natural enemies. Native grasses also improve soil water content and may be part of a water conservation program for perennial crops in dry climate regions.