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Asteroids smaller than 10 km are thought to be rubble piles formed from the reaccumulation of fragments produced in the catastrophic disruption of parent bodies. Ground-based observations reveal that some of these asteroids are today binary systems, in which a smaller secondary orbits a larger primary asteroid. However, how these asteroids became binary systems remains unclear. Here, we report the analysis of boulders on the surface of the stony asteroid (65803) Didymos and its moonlet, Dimorphos, from data collected by the NASA DART mission. The size-frequency distribution of boulders larger than 5 m on Dimorphos and larger than 22.8 m on Didymos confirms that both asteroids are piles of fragments produced in the catastrophic disruption of their progenitors. Dimorphos boulders smaller than 5 m have size best-fit by a Weibull distribution, which we attribute to a multi-phase fragmentation process either occurring during coalescence or during surface evolution. The density per km2 of Dimorphos boulders ≥1 m is 2.3x with respect to the one obtained for (101955) Bennu, while it is 3.0x with respect to (162173) Ryugu. Such values increase once Dimorphos boulders ≥5 m are compared with Bennu (3.5x), Ryugu (3.9x) and (25143) Itokawa (5.1x). This is of interest in the context of asteroid studies because it means that contrarily to the single bodies visited so far, binary systems might be affected by subsequential fragmentation processes that largely increase their block density per km2. Direct comparison between the surface distribution and shapes of the boulders on Didymos and Dimorphos suggest that the latter inherited its material from the former. This finding supports the hypothesis that some asteroid binary systems form through the spin up and mass shedding of a fraction of the primary asteroid. By comparing boulders' surface distribution and shapes on the binary asteroid system, Didymos, authors show that both bodies are rubble piles produced in their progenitor catastrophic disruption and that the secondary, Dimorphos, likely inherited its material from the primary through spin up and mass shedding. [ABSTRACT FROM AUTHOR]

Spacecraft observations revealed that rocks on carbonaceous asteroids, which constitute the most numerous class by composition, can develop millimeter-to-meter-scale fractures due to thermal stresses. However, signatures of this process on the second-most populous group of asteroids, the S-complex, have been poorly constrained. Here, we report observations of boulders' fractures on Dimorphos, which is the moonlet of the S-complex asteroid (65803) Didymos, the target of NASA's Double Asteroid Redirection Test (DART) planetary defense mission. We show that the size-frequency distribution and orientation of the mapped fractures are consistent with formation through thermal fatigue. The fractures' preferential orientation supports that these have originated in situ on Dimorphos boulders and not on Didymos boulders later transferred to Dimorphos. Based on our model of the fracture propagation, we propose that thermal fatigue on rocks exposed on the surface of S-type asteroids can form shallow, horizontally propagating fractures in much shorter timescales (100 kyr) than in the direction normal to the boulder surface (order of Myrs). The presence of boulder fields affected by thermal fracturing on near-Earth asteroid surfaces may contribute to an enhancement in the ejected mass and momentum from kinetic impactors when deflecting asteroids. Here, authors study boulders' fractures on S-type asteroid, Dimorphos, and show that their size-frequency distribution and orientation are consistent with formation through thermal fatigue. Such fractures seem to propagate horizontally much faster (~kyr) than normal to the boulder's surface (~Myr). [ABSTRACT FROM AUTHOR]

To achieve high-thrust-density operation, we propose electrostatic–magnetic hybrid ion acceleration in which the empirical thrust density limit of the electrostatic acceleration is surpassed without violent plasma oscillation by combing the collisional momentum transfer mechanism, which is the ion acceleration mechanism of the electromagnetic acceleration. To achieve hybrid ion acceleration, we experimentally obtained two design criteria: one near anode propellant injection and another at the on-axis hollow cathode location. The thrust characteristics of three thrusters composed of a slowly diverging magnetic field between an on-axis hollow cathode and a coaxially set ring anode were examined. By injecting xenon propellant along the anode inner surface, the electron impact ionization process was enhanced, and generated ions are electrostatically accelerated through the radial-inward potential gradient perpendicular to the axial magnetic lines of force. The hybrid ion acceleration characteristics were obtained only if these two criteria were satisfied and the obtained thrust was consistent with the thrust formula derived for steady-state, quasi-neutral plasma flows. In addition to the criteria, strengthening the magnetic field and enhancing the propellant mass flux were effective for improving thrust density without deteriorating thrust efficiency. Among the experimental conditions in this study, the maximum thrust density was 70 N/m2 with an anode specific impulse of 1200 s, which cannot be achieved in a purely electrostatic thruster with thrust density 6.3 times than that of a typical Hall thruster. [ABSTRACT FROM AUTHOR]

The correction notice in Nature Communications addresses the omission of funding from the Spanish project PID2021-128062NB-I00 in the original article on the multi-fragmentation and mass shedding of boulders on the rubble-pile binary asteroid system (65803) Didymos. The authors have provided a list of contributors to the article, which includes a diverse group of researchers from various institutions. The corrected version of the article can be accessed online for further information. [Extracted from the article]

Anaphes (Anaphes) flavipes (Foerster), a fairyfly (Hymenoptera: Mymaridae) native of Europe, is an economically important egg parasitoid for the natural control of Oulema spp. leaf beetle (Coleoptera: Chrysomelidae) pests of cereal crops such as barley, oats, rye, and wheat in Europe, and for the classical biological control of the invasive Oulema melanopus (L.) in North America. A morphologically very similar Anaphes (Anaphes) nipponicus Kuwayama, known from mainland China, Japan, Republic of Korea, Far East of Russia and Taiwan, is an egg parasitoid of Oulema oryzae (Kuwayama), a pest of rice mainly in temperate parts of East Asia. The nuclear 28S-D2 and ITS2 and the mitochondrial COI genes were used as markers to compare specimens of A. (Anaphes) flavipes reared from eggs of an Oulema sp. on barley in Germany with those of A. (Anaphes) nipponicus reared from eggs of O. oryzae on rice in Honshu Island, Japan. Because the resulting sequences are practically identical, within an expected intraspecific genetic variability, conspecificity of these two nominal species has been confirmed, and consequently A. (Anaphes) nipponicus Kuwayama, 1932, syn. n. is synonymized with A. (Anaphes) flavipes (Foerster, 1841). Taxonomic notes and illustrations are provided for the specimens of both sexes of A. (Anaphes) flavipes from Japan to facilitate their recognition. [ABSTRACT FROM AUTHOR]

Cancer-promoting inflammation is an important event in cancer development. Canine urothelial carcinoma (cUC) overexpresses prostaglandin E2 (PGE2) and has a unique sensitivity to cyclooxygenase 2 (COX2)-inhibiting therapy. In addition, majority of cUC harbour BRAFV595E mutation. However, mechanisms underlying aberrant PGE2 production in BRAFV595E cUC patients remain unclear. Drug screening revealed that inhibition of RAF/MEK/ERK pathway, p38 and JNK pathway reduced PGE2 production in cUC cells. By pharmacological inhibition of the multiple components in the pathway, activation of the ERK MAPK pathway was shown to mediate overexpression of COX2 and production of PGE2 in BRAFV595E cUC cells. In silico gain-of-function analysis of the BRAF mutation also implicated involvement of mutation in the process. The positive association between ERK activation and COX2 expression was further validated in the clinical patients. Moreover, it was also suggested that p38 and JNK regulates PGE2 production independently of ERK pathway, possibly through COX2-dependent and COX1-/COX2- independent manner, respectively. In conclusion, this study demonstrated that activation of ERK induces production of PGE2 in BRAFV595E cUC cells, which is also independently regulated by p38 and JNK. With its unique vulnerability to COX-targeted therapy, BRAFV595E cUC may serve as a valuable model to study the tumour-promoting inflammation. [ABSTRACT FROM AUTHOR]

We report the synthesis and characterisation of palladium complexes bearing an N-heterocyclic carbene–phosphine oxide bidentate ligand and their use as catalysts for ethylene polymerisation and ethylene/polar monomer copolymerisation. [ABSTRACT FROM AUTHOR]

Pregnant women tend to fall and increased body postural instability, namely body sway, may be one of the causative factors. We had a clinical impression that pregnant women after long-term bed rest tend to fall. We hypothesised that such women may show increased body sway, which we attempted to determine. Pregnant women (n= 161) were divided into three groups: (i) women with preterm labour after 2-week bed rest, (ii) those after 4-week bed rest, and (iii) those without bed rest or preterm labour. Body sway was analysed using stabilometry, that is, computed analysis of movement of the centre of gravity. The 3 groups fundamentally showed the same stabilometric measurements. Women with oedema showed greater medial–lateral sway than those without it. Factors other than oedema yielded no differences in stabilometric parameters. Long-term bed rest fundamentally did not increase body sway to the extent that stabilometry could reveal it. It may be prudent to consider that pregnant women with oedema tend to fall. [ABSTRACT FROM PUBLISHER]

To determine whether the nocturnal decrease in arginine vasopressin (AVP) secretion into the plasma, found in a patient with multiple system atrophy (MSA) reported previously, is a usual finding in MSA, the plasma AVP concentrations in 13 patients with MSA were measured every 4 hours during a 24 hour period. The plasma AVP concentrations in these patients showed significant daily variations and were the lowest during the night. This finding indicates that patients with MSA often exhibit nocturnal decrease in AVP secretion into the plasma. The results suggest the possibility that the system responsible for the daily variations in AVP secretion is involved in MSA. [ABSTRACT FROM AUTHOR]

Background:The polypeptide N-acetylgalactosaminyltransferases (GalNAc-Ts) family of enzymes regulates the initial steps of mucin-type O-glycosylation. N-acetylgalactosaminyltransferases might show novel patterns of GalNAc-T glycosylation on tumour-derived proteins, which could influence cancer biology, but its mechanisms are unclear. We investigated the association of GalNAc-T3 and -T6 expressions with clinicopathological features and prognoses of patients with renal cell carcinomas (RCCs).Methods:Expressions of GalNAc-T3/6 and cell-adhesion molecules were analysed immunohistochemically in 254 paraffin-embedded tumour samples of patients with RCC.Results:Of 138 GalNAc-T3+ cases, 46 revealed significant co-expression with GalNAc-T6. N-acetylgalactosaminyltransferases-3+ expression showed a close relationship to poor clinical performance and large tumour size, or pathologically high Fuhrman's grading, and presence of vascular invasion and necrosis. The GalNAc-T3-positivity potentially suppressed adhesive effects with a significantly low β-catenin expression. Univariate and multivariate analyses showed the GalNAc-T3+ group, but not the GalNAc-T6+ group, to have significantly worse survival rates.Conclusion:N-acetylgalactosaminyltransferases-3 expression independently predicts high-grade tumour and poor prognosis in patients with RCC, and may offer a therapeutic target against RCC. [ABSTRACT FROM AUTHOR]

Background: The family of polypeptide N-acetylgalactosaminyltransferases (GalNAc-Ts) is responsible for the altered glycosylation in cancer. The purpose of our study was to investigate the clinical significance of two isoforms, GalNAc-T6 and -T3, and their correlation with the prognosis of pancreatic cancer.Methods: Immunohistochemistry was used to analyse GalNAc-T6 and -T3 expressions in 70 clinicopathologically characterised pancreatic cancer cases.Results: Positive expressions of GalNAc-T6 and -T3 were immunohistochemically identified in 51% (36 of 70) and in 77% (54 of 70) of patients, respectively. A close relationship was noted between GalNAc-T6 positive expression and pathological well/moderate differentiated type (P=0.001), small tumour size (P=0.044), absence of vascular invasion (P=0.009), and low stage of the American Joint Committee on Cancer systems (P=0.043). The expression of GalNAc-T3 significantly correlated with good differentiation (P=0.001), but not with other clinicopathologic features. Furthermore, univariate and multivariate analyses revealed that GalNAc-T6 expression was an independent prognosis indicator for the disease, whereas GalNAc-T3 expression had no impact on clinical outcome, even though 33 of 36 GalNAc-T6-positive cases also had a positive expression of GalNAc-T3 (P=0.001, r=0.356).Conclusion: Both GalNAc-T6 and -T3 expressions correlated significantly with tumour differentiation, whereas only GalNAc-T6 expression predicted prognosis in pancreatic cancer. [ABSTRACT FROM AUTHOR]

During physiological stress, ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) degradation is accelerated, which is considered to be one of the key factors responsible for photosynthetic decline. A recent study has shown that the large subunit (RbcL) of Rubisco is directly fragmented by hydroxyl radicals in Cucumis sativus leaves under chilling-light conditions. In the present study, we investigated biochemical aspects associated with this in vivo RbcL fragmentation by reactive oxygen species. RbcL fragmentation was observed in C. sativus and Phaseolus vulgaris, but not in Solanum lycopersicum, Glycine max, Oryza sativa, Triticum aestivum, Spinacia oleracea or Arabidopsis thaliana. In C. sativus and P. vulgaris, RbcL fragmentation followed the fragmentation of PsaB, while in the other species, PsaB fragmentation did not occur. In C. sativus and P. vulgaris, the activities of antioxidant enzymes decreased dramatically under chilling-light conditions, and the proportion of uncarbamylated Rubisco increased. These data suggest that in vivo RbcL fragmentation under chilling-light conditions is associated with a combination of events, namely, inactivation of antioxidant enzymes, destruction of photosystem I and an increase of uncarbamylated Rubisco, which can produce hydroxyl radicals via the Fenton reaction at the catalytic site of RbcL. [ABSTRACT FROM AUTHOR]

Ultrasonic hearing is widespread among moths, but very few moth species have been reported to produce ultrasounds for sexual communication. In those that do, the signals are intense and thus well matched for long distance communication. By contrast, males of the Asian corn borer moth (Crambidae) were recently shown to whisper extremely low-intensity ultrasonic courtship songs close to females. Since low sound levels will prevent eavesdropping by predators, parasites and conspecific rivals, we predicted low intensity ultrasound communication to be widespread among moths. Here we tested 13 species of moths including members of the Noctuidae, Arctiidae, Geometridae and Crambidae. Males of nine species, 70%, produced broadband ultrasound close to females. Peak frequencies ranged from 38 to above 100kHz. All sounds were of low intensity, 43-76dBSPL at 1cm [64±10dBpeSPL (mean ± s.d.), N=9 species]. These quiet and/or hyper-frequency ultrasounds are audible to nearby mates, but inaudible to unintended receivers. Although largely unknown because it is so inconspicuous, acoustic communication using low intensity ultrasound appears to be widespread among hearing moths. Thus, acoustic communication may be the norm rather than the exception. [ABSTRACT FROM AUTHOR]

Contrast-enhanced CT revealed a hypovascular tumor filling the MPD of the pancreatic head with dilation of the upstream pancreatic duct (Figure 1a, 1b). Gastrointestinal: A case of a pancreatobiliary-type intraductal papillary mucinous neoplasm of the pancreas filling the main pancreatic duct without visible mucin secretion We have reported a case of a pancreatobiliary (PB)-type intraductal papillary mucinous neoplasm (IPMN) filling the main pancreatic duct (MPD) without visible mucin secretion. [Extracted from the article]

In this study, streptozotocin-nicotinamide-induced mildly diabetic mice and streptozotocin-induced severely diabetic mice were created to compare their characteristics and to investigate the effects of antidiabetic drugs on glucose tolerance. In severely diabetic mice, the pancreatic insulin content decreased to approximately 10% of levels found in normal mice. These mice also showed a decrease in body weight, a marked increase in nonfasting blood glucose levels and urinary glucose excretion, and a marked decline in glucose tolerance due to insulin secretory deficiency. In contrast, the pancreatic insulin content was approximately 50% of normal levels in mildly diabetic mice. These mice did not show any change in body weight, but displayed a mild increase in nonfasting blood glucose levels and urinary glucose excretion, and a mild decline in glucose tolerance due to loss of early-phase insulin secretion. Administration of antidiabetic drugs, namely voglibose, metformin, glibenclamide, sitagliptin and insulin, significantly improved glucose tolerance in mildly diabetic mice. In severely diabetic mice, voglibose, metformin and insulin significantly improved glucose tolerance, but no significant effect was observed for glibenclamide and sitagliptin due to a decreased insulinotropic effect. These results demonstrate that streptozotocin-nicotinamide-induced mildly diabetic mice have many pathological features resembling type 2 diabetes, and can serve as models for the pharmacological evaluation of many antidiabetic drugs. [ABSTRACT FROM AUTHOR]

We have proposed and been developing a new broad-band terahertz (THz) radiation detector using a Nb-based superconducting tunnel junction (STJ). The STJ's were fabricated on LiNbO3 and LiTaO3 mono-crystal substrates. We radiated monochromatic THz pulses in the range 1-2 THz with the pulse repetition rate of 49 Hz, and successfully detected the corresponding periodic signals via a charge-sensitive preamplifier. The current signal obtained by the derivative of the output signal gave the time response of about 15-20 microseconds. The frequency response was compared with that of a conventional pyro-electric sensor. We found their frequency response showed the similar shape in frequency, demonstrating the flat response of the STJ detector in 1-2 THz. These results show that the detector can be used as a broad-band THz and far-infrared radiation detector above the frequency corresponding to the energy gap of the superconductor used for the base electrode. [ABSTRACT FROM AUTHOR]

We report a Japanese family with autosomal dominant adult-onset amyotrophic lateral sclerosis (FALS) with onset in the bulbar musculature, clinically benign course, absence of the Cu/Zn superoxide dismutase-1 (SOD 1) gene mutation, and many Bunina bodies, in addition to involvement of the upper and lower motor neurons. The proband was a Japanese woman who was 66 years old at the time of death. Family history disclosed five patients with FALS over three generations. She developed dysarthria at age 57, followed by dysphagia, muscle weakness of the upper extremities, and difficulty in respiration. She could walk without support until her death. The elder sister of the proband developed dysarthria at age 48 and died at age 58. A genetic study of the nephew of the proband showed the absence of a mutation in the SOD 1 gene. Neuropathological examination of the proband disclosed neuronal loss in the upper and lower motor neurons, and numerous Bunina bodies in the lower motor neurons without Lewy body-like inclusions or ubiquitin-immunoreactive neuronal inclusions. No degeneration of the Clarke’s column, middle root zone of the posterior column, or posterior spinocerebellar tract was present. Review of the literature revealed that only patients with FALS with a long survival period of over 5 years had pathological findings consistent with FALS with posterior column involvement. This study contributes to the elucidation of the clinicopathological heterogeneity of FALS. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare postprandial hemodynamic changes observed during assumption of the recumbent posture and upright posture in patients with cirrhosis and portal hypertension. Eleven patients with cirrhosis and portal hypertension were studied. Echo-Doppler examinations were performed to measure flow volume in the portal vein (PV), superior mesenteric artery (SMA), and splenic artery (SA) in the fasting condition. Collateral blood flow was indirectly calculated by determining the difference between the sum of SMA, SA, and PV blood flows. After these measurements were done, each patient received a standardized liquid meal and was then randomly assigned to either maintain supine or upright posture, in a crossover design, on 2 different days (recumbent day and upright day). On each study day, the above-mentioned measurements were repeated 30 min and 60 min after the meal. PV blood flow increased significantly after the meal on the recumbent day (P < 0.01) but not on the upright day (P = 0.78). Although there were significant postprandial increases in SMA blood flow on both study days (P < 0.01, P < 0.01), the effect was less pronounced on the upright day than on the recumbent day (P < 0.01). Postprandial SA blood flow showed no change on the recumbent day (P = 0.64), but decreased significantly on the upright day (P < 0.01). The calculated postprandial collateral blood flow increased significantly on the recumbent day (P < 0.05), but showed no change on the upright day (P = 0.53). These results suggest that the upright posture blunts postprandial splanchnic hyperemia in patients with cirrhosis and portal hypertension. [ABSTRACT FROM AUTHOR]

Self-incompatibility of Ipomoea trifida is under the control of a single multi-allelic locus, called the S-locus, and is genetically the same as the sporophytic system found in some species of Brassica. We investigated whether the S-locus-specific glycoprotein ( SLG) and S receptor kinase ( SRK) genes associated with the self-incompatibility of Brassica are expressed in the reproductive tissues of I. trifida. We amplified mRNAs from reproductive tissues of I. trifida by reverse transcriptase PCR using primers corresponding to conserved regions of the Brassica SLGs. Four kinds of PCR fragments were amplified in this experiment. These fragments were designated IPG1 to IPG4 based on dot-blot cross-hybridization. Nucleotide sequencing of the clones revealed 40-46% similarity to the Brassica SLGs and SRKs at the protein level. Northern analysis using IPG1 as a probe revealed a major transcript of 2.8 kb that would correspond in size to a fully spliced SRK transcript of Brassica. The transcript for IPG1 was detected in both mature stigma and anther tissue and was developmentally regulated. The experimental results reported here indicate that at least four kinds of SLG/SRK-like genes are expressed in the reproductive tissues of Ipomoea. [ABSTRACT FROM AUTHOR]

In the present study, we investigated the effect of ambient pressure on [3H]-thymidine incorporation and on the production of matrix metalloproteinase 1 (tissue collagenase/proMMP-1) using human aortic endothelial cells immortalized with simian virus 40 (SE-1). Incubation of cells at ambient pressures of 50 and 100 mmHg for 24 h slightly increased [3H]-thymidine incorporation when directly compared with normal culture conditions. The amount of [3H]-thymidine incorporated in SE-1 reached a maximum at 150 mmHg, while a further increase in pressure to 200 mmHg decreased incorporation. The same ambient pressure slightly stimulated human aortic intimal smooth muscle cells (SMC) to increase [3H]-thymidine incorporation but not medial SMC. Immunoblot analysis also showed that ambient pressure, ranging from 50 to 200 mmHg, like 12-O-tetradecanoyl-phorbol-13-acetate stimulated SE-1 to produce proMMP-1, an effect not seen with either intimal or medial SMC. The amount of proMMP-1 produced also reached a maximum level at 150 mmHg. We postulate that human endothelial cells are ambient pressure sensitive and that relatively lower ambient pressures play an important role in the growth of endothelial cells, while higher pressures injure endothelial cells, resulting in the initiation of atherosclerosis. This cell line may prove useful in the investigation of both the physiological and pathological roles of blood pressure on endothelial cell function. [ABSTRACT FROM AUTHOR]