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Chirality plays a fundamental role in biology and chemistry and the precise control of chirality in a catalytic conversion is a key to modern synthesis most prominently seen in the production of pharmaceuticals. In enantioselective metal-based catalysis, access to each product enantiomer is commonly achieved through ligand design with chiral bisphosphines being widely applied as privileged ligands. Switchable phosphine ligands, in which chirality is modulated through an external trigger signal, might offer attractive possibilities to change enantioselectivity in a catalytic process in a non-invasive manner avoiding renewed ligand synthesis. Here we demonstrate that a photoswitchable chiral bisphosphine based on a unidirectional light-driven molecular motor, can be used to invert the stereoselectivity of a palladium-catalysed asymmetric transformation. It is shown that light-induced changes in geometry and helicity of the switchable ligand enable excellent selectivity towards the racemic or individual enantiomers of the product in a Pd-catalysed desymmetrization reaction. Typically in asymmetric catalysis each product enantiomer is produced using a different enantiomer of catalyst. Here, the authors show a photoswitchable bisphosphine ligand, capable of altering the stereoselectivity of a palladium catalysed process and producing either enantiomer of product.

Let G be a subgraph of the complete bipartite graph K l , m , l ≤ m , with e = q m + p > 0 , 0 ≤ p < m , edges. The maximal value of the sum of the squares of the degrees of the vertices of G is q m 2 + p 2 + p ( q + 1 ) 2 + ( m - p ) q 2 . We classify all graphs that attain this bound using the diagonal sequence of a partition.

Clinical practice guidelines recommend surgical referral for patients with severe symptoms, thenar atrophy, or positive findings on electrodiagnostic testing.5 Mild to moderate CTS should be treated with splinting, injections, occupational therapy, or surgery.4 The 2024 Cochrane review discussed here evaluated the benefits and harms of surgical vs various nonsurgical treatments for CTS in adults.6 The systematic review found 14 randomized controlled trials (RCTs) comparing surgery vs splinting, corticosteroid injection, splinting plus corticosteroid injection, platelet-rich plasma injection, manual therapy, multimodal nonoperative treatment, and unspecified medical treatment and hand support. [...]this review compared outcomes from treatment-naive patients, limiting the applicability to this population and its generalizability to patients who have already been treated with nonsurgical therapies. Additionally, the evidence is uncertain about whether surgery vs corticosteroid injection results in beneficial long-term clinical improvement or difference in harms. [...]shared decision-making should be used, considering disease severity and duration, along with patient concerns, previous treatments, occupation, goals, and preferences.

Purpose The aim of the present review was to determine effects of strength exercise on secondary lymphedema in breast cancer patients. Methods Research was conducted by using the databases PubMed/Medline and Embase. Randomized controlled trials published from January 1966 to May 2015 investigating the effects of resistance exercise on breast cancer patients with or at risk of secondary lymphedema in accordance with the American College of Sports Medicine exercise guidelines for cancer survivors were included in the present study. Results Nine original articles with a total of 957 patients met the inclusion criteria. None of the included articles showed adverse effects of a resistance exercise intervention on lymphedema status. In all included studies, resistance exercise intensity was described as moderate to high. Conclusions Strength exercise seems not to have negative effects on lymphedema status or might not increase risk of development of lymphedema in breast cancer patients. Further research is needed in order to investigate the effects of resistance exercise for patients suffering from lymphedema.

Multi-messenger astrophysics is a fast-growing, interdisciplinary field that combines data, which vary in volume and speed of data processing, from many different instruments that probe the Universe using different cosmic messengers: electromagnetic waves, cosmic rays, gravitational waves and neutrinos. In this Expert Recommendation, we review the key challenges of real-time observations of gravitational wave sources and their electromagnetic and astroparticle counterparts, and make a number of recommendations to maximize their potential for scientific discovery. These recommendations refer to the design of scalable and computationally efficient machine learning algorithms; the cyber-infrastructure to numerically simulate astrophysical sources, and to process and interpret multi-messenger astrophysics data; the management of gravitational wave detections to trigger real-time alerts for electromagnetic and astroparticle follow-ups; a vision to harness future developments of machine learning and cyber-infrastructure resources to cope with the big-data requirements; and the need to build a community of experts to realize the goals of multi-messenger astrophysics.A group of experts suggests ways in which deep learning can be used to enhance the potential for discovery in multi-messenger astrophysics.

The Cassini magnetometer has detected the interaction of the magnetospheric plasma of Saturn with an atmospheric plume at the icy moon Enceladus. This unanticipated finding, made on a distant flyby, was subsequently confirmed during two follow-on flybys, one very close to Enceladus. The magnetometer data are consistent with local outgassing activity via a plume from the surface of the moon near its south pole, as confirmed by other Cassini instruments.

On the basis of previous ground-based and fly-by information, we knew that Titan's atmosphere was mainly nitrogen, with some methane, but its temperature and pressure profiles were poorly constrained because of uncertainties in the detailed composition. The extent of atmospheric electricity (‘lightning’) was also hitherto unknown. Here we report the temperature and density profiles, as determined by the Huygens Atmospheric Structure Instrument (HASI), from an altitude of 1,400 km down to the surface. In the upper part of the atmosphere, the temperature and density were both higher than expected. There is a lower ionospheric layer between 140 km and 40 km, with electrical conductivity peaking near 60 km. We may also have seen the signature of lightning. At the surface, the temperature was 93.65 ± 0.25 K, and the pressure was 1,467 ± 1 hPa. New views of Titan The Huygens probe landed on Titan on 14 January this year, and seven papers published in this issue record the encounter. They describe a world that resembles a primitive Earth, complete with weather systems and geological activity. The ‘Huygens on Titan’ section opens with an overview of the descent and landing and a News and Views piece. Tomasko et al . describe the dry riverbed and drainage channels seen during Huygens' descent, evidence that liquid methane falls as rain or erupts from cryovolcanoes, periodically flooding the surface. This paper includes the images used on the cover to the Huygens section. Niemann et al . measured the abundances of isotopes of argon, nitrogen and carbon in the atmosphere, and conclude that there is no evidence that Titan's methane comes from biological activity. Fulchignoni et al . obtained precise measurements of temperature and pressure from the upper atmosphere right down to the surface. On the way down Huygens recorded evidence for lightning. Zarnecki et al . report that the probe landed on a relatively smooth surface of icy grains with the consistency of wet clay or sand. Isräl et al . report that the aerosols in Titan's clouds have solid cores made from complex organic molecules containing carbon and nitrogen. And Bird et al . found that on average Titan's winds blow in the same direction as the moon rotates, and that close to the surface these winds are very weak, travelling at around walking speed.

The solar wind at the orbit of the Earth is usually strongly super‐Alfvénic and super‐fast, causing a bow‐shock to be formed upstream of the Earth's magnetosphere. We here present observational evidence that during 24 and 25 May 2002, the solar wind at the Earth was sub‐Alfvénic (with an Alfvén Mach number as low as 0.4 in the rest frame of the Earth) and was therefore sub‐fast for time periods of up to four hours. The low Alfvén Mach number implies that the Earth's bow‐shock disappeared and two Alfvén wings formed. These Alfvén wings are two structures on both the East and West side of the Earth's magnetosphere, where the solar wind plasma is decelerated and the magnetic field direction changes. We present observations of the Geotail spacecraft, which are consistent with Geotail entering the foot of one of these Alfvén wings. We estimate that these wings reached an extension of 600 RE. Even though Alfvén wings are present at several moons in the solar system (e.g., Io, Europa, Enceladus) and are likely to occur at some extrasolar planets, this is the first time that they are observed at the Earth. We also study how the Earth is affected by this transition from a super‐fast to a sub‐Alfvénic environment and how the Alfvén wings are affected by the constantly varying solar wind. The sub‐Alfvénic solar wind is due to very low density in the solar wind. While the solar wind Alfvén Mach number was very low, the magnetosphere was geomagnetically extremely quiet. Whereas the SYM‐H index indicates a recovery phase from a small to moderate magnetic storm; the AL and AU indices show no substorm activity. In addition, there was almost no auroral activity. Key Points Earth bow shock disappeared due to long sub‐Alfvenic solar wind interval Two Alfven wings were formed and reached a size of up to 600 Re

After 3 years and 31 close flybys of Titan by the Cassini Orbiter, Titan was finally observed in the shocked solar wind, outside of Saturn's magnetosphere. These observations revealed that Titan's flow-induced magnetosphere was populated by \"fossil\" fields originating from Saturn, to which the satellite was exposed before its excursion through the magnetopause. In addition, strong magnetic shear observed at the edge of Titan's induced magnetosphere suggests that reconnection may have been involved in the replacement of the fossil fields by the interplanetary magnetic field.

Correlations are studied between the power density of transverse waves having frequencies between 0.01 and 1 normalized to the proton gyrofrequency in the plasma frame and the ratio of the perpendicular and parallel temperature of the protons. The wave power spectrum is evaluated from high‐resolution 3D magnetic field vector components, and the ion temperatures are derived from the velocity distribution functions as measured in fast solar wind during the Helios‐2 primary mission at radial distances from the Sun between 0.3 AU and 0.9 AU. From our statistical analysis, we obtain a striking correlation between the increases in the proton temperature ratio and enhancements in the wave power spectrum. Near the Sun the transverse part of the wave power is often found to be by more than an order of magnitude higher than its longitudinal counterpart. Also the measured ion temperature anisotropy appears to be limited by the theoretical threshold value for the ion‐cyclotron instability. This suggests that high‐frequency Alfvén‐cyclotron waves regulate the proton temperature anisotropy.