Explore the vast range of titles available.

In ferromagnets, an electric current generally induces a transverse Hall voltage in proportion to the internal magnetization. This effect is frequently used for the electrical readout of the spin-↑ and spin-↓ states. Although these properties are usually not expected in antiferromagnets, recent theoretical studies predicted that a non-coplanar antiferromagnetic order with finite scalar spin chirality—meaning a solid angle spanned by neighbouring spins—can induce a large spontaneous Hall effect even without a net magnetization or external magnetic field. This phenomenon—the spontaneous topological Hall effect—can potentially be used for the efficient electrical readout of antiferromagnetic states, but it has not been experimentally verified due to a lack of appropriate materials hosting such magnetism. Here we report the discovery of an all-in–all-out-type non-coplanar antiferromagnetic order in triangular lattice compounds CoTa3S6 and CoNb3S6. These compounds are reported to host unconventionally large spontaneous Hall effects despite their vanishingly small net magnetization, and our analysis reveals that it can be explained in terms of the topological Hall effect that originates from the fictitious magnetic field associated with scalar spin chirality. These results indicate that the scalar spin chirality mechanism offers a promising route to the realization of a giant spontaneous Hall response even in compensated antiferromagnets, and highlight intercalated van der Waals magnets as a promising quasi-two-dimensional material platform to enable various non-trivial ways of electrical reading and the possible writing of non-coplanar antiferromagnetic domains.The spontaneous topological Hall effect, combining non-coplanar antiferromagnetic order with finite scalar spin chirality in the absence of a magnetic field, is now experimentally demonstrated for the triangular lattice compounds CoTa3S6 and CoNb3S6.

Topological swirling spin textures, such as skyrmions and merons, have recently attracted much attention as potential building blocks for high-density magnetic information devices. Controlling the transformation between different types of these quasiparticles is an important challenge. To date, these transitions have mostly been limited to a few non-centrosymmetric systems, where they are driven by the Dzyaloshinskii–Moriya interaction. Here we demonstrate multistep topological transitions among a variety of meron and skyrmion crystal states in a centrosymmetric magnet GdRu 2 Ge 2 . These are governed by the competition between Ruderman–Kittel–Kasuya–Yosida interactions at inequivalent wave vectors. These findings demonstrate that even a simple centrosymmetric magnet with competing interactions can be a promising material platform to realize a richer variety of magnetic quasiparticles with distinctive symmetry and topology, whose stability can be tuned by various external stimuli. Topological magnetic spin structures such as skyrmions and merons have the potential to be used in magnetic information devices. Now multistep transformations between such structures are demonstrated in a centrosymmetric material.

Mammography is the only proven method for breast cancer screening that reduces mortality, although it is inaccurate in young women or women with dense breasts. We investigated the efficacy of adjunctive ultrasonography. Between July, 2007, and March, 2011, we enrolled asymptomatic women aged 40–49 years at 42 study sites in 23 prefectures into the Japan Strategic Anti-cancer Randomized Trial (J-START). Eligible women had no history of any cancer in the previous 5 years and were expected to live for more than 5 years. Randomisation was done centrally by the Japan Clinical Research Support Unit. Participants were randomly assigned in 1:1 ratio to undergo mammography and ultrasonography (intervention group) or mammography alone (control group) twice in 2 years. The primary outcome was sensitivity, specificity, cancer detection rate, and stage distribution at the first round of screening. Analysis was by intention to treat. This study is registered, number UMIN000000757. Of 72 998 women enrolled, 36 859 were assigned to the intervention group and 36 139 to the control group. Sensitivity was significantly higher in the intervention group than in the control group (91·1%, 95% CI 87·2–95·0 vs 77·0%, 70·3–83·7; p=0·0004), whereas specificity was significantly lower (87·7%, 87·3–88·0 vs 91·4%, 91·1–91·7; p<0·0001). More cancers were detected in the intervention group than in the control group (184 [0·50%] vs 117 [0·32%], p=0·0003) and were more frequently stage 0 and I (144 [71·3%] vs 79 [52·0%], p=0·0194). 18 (0·05%) interval cancers were detected in the intervention group compared with 35 (0·10%) in the control group (p=0·034). Adjunctive ultrasonography increases sensitivity and detection rate of early cancers. Ministry of Health, Labour and Welfare of Japan.

The purpose of this study was to compare the muscle synergies extracted from 14 unilateral lower‐limb and trunk muscles between the first and final parts of a 400‐m sprint in experienced sprinters to understand neuromuscular coordination of multiple muscles in the fatigued condition sprint. Nine male 400‐m sprinters (400‐m personal record: 48.11 ± 1.6 s) performed 400‐m sprints as with the real competition strategy. We defined the first part (100–150 m section) and the final part (350–400 m section), and obtained mean spatiotemporal variables (e.g., running speed, step frequency, and step length) for both parts. Electromyography (EMG) signals were obtained using wireless EMG sensors (2000 Hz) from 14 lower‐limb and trunk muscles. Non‐negative matrix factorization was performed to extract the muscle synergies for both parts. We observed significantly declined spatiotemporal variables in the final part induced by fatigue. The extracted number of synergies was 7.0 ± 0.7 (mean ± SD) for the first part and 7.2 ± 0.4 for the final part with no significant differences between parts. However, we identified specific muscle synergy, and alterations in the individual muscle weightings of several hip muscles (rectus femoris: RF, tensor fasciae latae: TFL, and glutes maximus: Gmax muscles) while there was no change in the muscle weighting of shank muscles and the temporal patterns of all muscles even following fatigue in the 400‐m sprint. Fatigue‐induced performance decline in a 400‐m sprint corresponds to alterations in muscle synergies, particularly in hip muscles, with notable shifts in RF, TFL, and Gmax activation. Highlights Running speed, step frequency, and step length significantly declined in the final part (350–400 m) compared to the first part (100–150 m) during the 400‐m maximal sprint due to fatigue. Number of muscle synergies was no significant differences between the first part (7.0 ± 0.7) and the final part (7.2 ± 0.4). Several hip muscle weighting components were altered, while no changes were observed in the shank muscles. The temporal patterns of all muscles remained consistent even after fatigue in the 400‐m sprint.

Purpose To evaluate the influence of cortical and cancellous bone structure on the biomechanical properties of all-suture and conventional anchors and compare the morphological bone damage after their failure. The hypothesis of the study is that all-suture anchor pullout is less invasive and that the pullout force is influenced by the cortical thickness. Methods Thirty human humeri were biomechanically tested as follows: starting with a load cycle from 20 to 50 N, a stepwise increase of the upper peak force by 0.05 N for each cycle at a rate of 1 Hz was performed. Analysis included maximum pullout strength for three different anchor implantation angles (45°, 90°, 110°) of the two anchor types. After anchor pullout, every sample underwent micro-CT analysis. Bone mineral density (BMD) and cortical thickness were determined at the anchor implantation site. Furthermore, the diameter of the cortical defect and the volume of the bone cavity were identified. Results The maximum pullout strength of all-suture anchors demonstrates a strong correlation to the adjacent cortical thickness ( r  = 0.82, p  ≤ 0.05) with at least 0.4 mm needed to withstand 200 N. No correlation could be seen in conventional anchors. Moreover, no correlation could be detected for local BMD in both anchors. All-suture anchors show a significantly narrower cortical defect as well as a smaller bone cavity following pullout (4.3 ± 1.3 mm vs. 5.3 ± 0.9 mm, p  = 0.037; 141 mm 3 vs. 212 mm 3 ; p  = 0.009). The cortical defect is largest if the anchors are placed at a 45° angle. Conclusion In contrast to conventional anchors, the pullout force of all-suture anchors depends on the thickness of the humeral cortex. Furthermore, all-suture anchors show a significantly smaller cortical defect as well as decreased bone damage in the case of pullout. Therefore, the clinical implication of this study is that all-suture anchors are advantageous due to their bone preserving ability. Also, intraoperative decortication should not be performed and cortical thickness should be preoperatively evaluated to decrease the risk of anchor failure.

The best chemotherapy regimen for metastatic gastric cancer is uncertain, but promising findings have been reported with irinotecan plus cisplatin and S-1 (tegafur, 5-chloro-2,4-dihydropyrimidine, and potassium oxonate). We aimed to investigate the superiority of irinotecan plus cisplatin and non-inferiority of S-1 compared with fluorouracil, with respect to overall survival, in patients with metastatic gastric cancer. We undertook a phase 3 open label randomised trial in 34 institutions in Japan. We enrolled patients aged 20–75 years or younger, who had histologically proven gastric adenocarcinoma, and randomly assigned them by minimisation to receive either: a continuous infusion of fluorouracil (800 mg/m 2 per day, on days 1–5) every 4 weeks (n=234); intravenous irinotecan (70 mg/m 2, on days 1 and 15) and cisplatin (80 mg/m 2, on day 1) every 4 weeks (n=236); or oral S-1 (40 mg/m 2, twice a day, on days 1–28) every 6 weeks (n=234). The primary endpoint was overall survival. Analyses were done by intention to treat. This study is registered with Clinicaltrials.gov, number NCT00142350, and with UMIN-CTR, number C000000062. All randomised patients were included in the primary analysis. Median overall survival was 10·8 months (IQR 5·7–17·8) for individuals assigned fluorouracil, 12·3 months (8·1–19·5) for those allocated irinotecan plus cisplatin (hazard ratio 0·85 [95% CI 0·70–1·04]; p=0·0552), and 11·4 months (6·4–21·3) for those assigned S-1 (0·83 [0·68–1·01]; p=0·0005 for non-inferiority). Three treatment-related deaths occurred in the irinotecan plus cisplatin group and one was recorded in the S-1 group. S-1 is non-inferior to fluorouracil and, in view of the convenience of an oral administration, could replace intravenous fluorouracil for treatment of unresectable or recurrent gastric cancer, at least in Asia. Irinotecan plus cisplatin is not superior to fluorouracil in this setting. Ministry of Health, Labour, and Welfare of Japan; Taiho Pharmaceutical; Yakult Honsha.

Robust transmission of information despite the presence of variation is a fundamental problem in cellular functions. However, the capability and characteristics of information transmission in signaling pathways remain poorly understood. We describe robustness and compensation of information transmission of signaling pathways at the cell population level. We calculated the mutual information transmitted through signaling pathways for the growth factor—mediated gene expression. Growth factors appeared to carry only information sufficient for a binary decision. Information transmission was generally more robust than average signal intensity despite pharmacological perturbations, and compensation of information transmission occurred. Information transmission to the biological output of neurite extension appeared robust. Cells may use information entropy as information so that messages can be robustly transmitted despite variation in molecular activities among individual cells.

Spring phytoplankton blooms play a major role in the carbon biogeochemical cycle of the Oyashio region, western subarctic Pacific, where the seasonal biological drawdown effect on seawater pCO₂ is one of the greatest among the world’s oceans. However, the bloom often terminates before depleting macronutrients, and the initiation and magnitude of the bloom is heterogeneous. We conducted a high resolution taxonomic and physiological assessment of phytoplankton in relation to the different physicochemical water masses of Coastal Oyashio Water (COW), Oyashio water (OYW), and modified Kuroshio water (MKW) in the Oyashio region from April to June 2007. Massive diatom blooms were found in April. Then, chlorophyll a concentration, cell abundance of diatom taxa, and the maximum photosystem II photochemical efficiency (F v/F m) were positively correlated with the mixing ratios of COW, suggesting that the spring bloom in April was strongly affected by the intrusion of COW. In the OYW, intensive blooms occurred from the middle of May under low dissolved iron (DFe) concentration (< 0.26 nM). Redundancy analysis showed that while diatom blooms accompanied by COW were related to DFe concentration, this was not the case in the OYW. These results indicated that diatoms in the OYW possess different iron adaptation strategies compared with diatoms in thewater masses affected by COW. This led to the spatial heterogeneity of the Oyashio spring bloom. The results presented here demonstrate that water mass characterization with detailed assessments of phytoplankton taxonomy and physiological status can improve our understanding of marine ecosystems.

Chromophoric dissolved organic matter (CDOM) ubiquitously occurs in marine environments and plays a significant role in the marine biogeochemical cycles. Basin scale distributions of CDOM have recently been surveyed in the global ocean and indicate that quantity and quality of oceanic CDOM are mainly controlled by in situ production and photobleaching. However, factors controlling the spectral parameters of CDOM in the UV region, i.e., spectral slope of CDOM determined at 275–295 nm (S275–295) and the ratio of two spectral slope parameters (SR); the ratio of S275–295 to S350–400, have not been well documented. To evaluate the factor controlling the spectral characteristics of CDOM in the UV region in the open ocean, we determined the quantitative and qualitative characteristics of CDOM in the subarctic and subtropical surface waters (5–300 m) of the western North Pacific. Absorption coefficients at 320 nm in the subarctic region were higher than those in the subtropical region throughout surface waters, suggesting that magnitudes of photobleaching were different between the two regions. The values of S275–295 and SR were also higher in the subtropical region than the subarctic region. The dark microbial incubation showed biodegradation of DOM little affected S275–295, but slightly decreased SR. On the other hand, increases in S275–295 and relative stableness of SR were observed during photo-irradiation incubations respectively. These experimental results indicated that photobleaching of CDOM mainly induced qualitative differences in CDOM at UV region between the subarctic and subtropical surface waters. The results of this study imply that S275–295 can be used as a tracer of photochemical history of CDOM in the open ocean.

Nitrogen isotope analysis of chloropigments provides information on the sources of nitrogenous nutrients assimilated by phytoplankton. The abundant, ubiquitous chlorophyll a records nitrogen isotopic compositions (δ15N) of eukaryotic phytoplankton and cyanobacteria, whereas more source‐specific chloropigments, such as the divinylchlorophylls exclusively possessed by the marine picocyanobacterium Prochlorococcus, can potentially resolve isotopic variability within the phytoplankton community. In this study, we analyzed the δ15N of both chlorophyll a and divinylchlorophyll a isolated from suspended particulate material collected at the subsurface chlorophyll maximum (SCM) along a meridional transect at 88°E in the oligotrophic eastern Indian Ocean. The nitrogen isotopic compositions of Prochlorococcus (δ15NPRO) and the combined biomass of eukaryotic phytoplankton and Synechococcus (δ15NEU+SYN) estimated from the δ15N of divinylchlorophyll a and chlorophyll a, respectively, revealed systematic variations that were not apparent from bulk isotope measurements. Whereas consistently low δ15NPRO indicated reliance of Prochlorococcus on regenerated nitrogen throughout the transect, elevation in δ15NEU+SYN values at several stations was interpreted to reflect assimilation of subsurface NO3− by eukaryotic phytoplankton. The δ15N distributions revealed subtle differences in NO3− availability at the SCM along the transect, which were consistently explained by the occurrence of mesoscale eddies in the Bay of Bengal, deepening of the mixed layer induced by a seasonal Wyrtki Jet in the equatorial region, and substantial deepening of the nutricline in the South Indian Ocean gyre. Our results highlight the utility of compound‐specific isotopic measurements of multiple species of chlorophylls in obtaining essential non‐incubation‐based biogeochemical constraints on the primary production in the ocean. Key Points We determined nitrogen sources for phytoplankton based on nitrogen isotopic measurements of chlorophyll a and divinylchlorophyll a Prochlorococcus depended on regenerated nitrogen whereas eukaryotic phytoplankton responded sensitively to the subsurface nitrate supply Phytoplankton responses were consistently explained by oceanographic conditions along a meridional transect in the eastern Indian Ocean