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Visual perception equips unmanned aerial vehicles (UAVs) with increasingly comprehensive and instant environmental perception, rendering it a crucial technology in intelligent UAV obstacle avoidance. However, the rapid movements of UAVs cause significant changes in the field of view, affecting the algorithms' ability to extract the visual features of collisions accurately. As a result, algorithms suffer from a high rate of false alarms and a delay in warning time. During the study of visual field angle curves of different orders, it was found that the peak times of the curves of higher-order information on the angular size of looming objects are linearly related to the time to collision (TTC) and occur before collisions. This discovery implies that encoding higher-order information on the angular size could resolve the issue of response lag. Furthermore, the fact that the image of a looming object adjusts to meet several looming visual cues compared to the background interference implies that integrating various field-of-view characteristics will likely enhance the model's resistance to motion interference. Therefore, this paper presents a concise A-LGMD model for detecting looming objects. The model is based on image angular acceleration and addresses problems related to imprecise feature extraction and insufficient time series modeling to enhance the model's ability to rapidly and precisely detect looming objects during the rapid self-motion of UAVs. The model draws inspiration from the lobula giant movement detector (LGMD), which shows high sensitivity to acceleration information. In the proposed model, higher-order information on the angular size is abstracted by the network and fused with multiple visual field angle characteristics to promote the selective response to looming objects. Experiments carried out on synthetic and real-world datasets reveal that the model can efficiently detect the angular acceleration of an image, filter out insignificant background motion, and provide early warnings. These findings indicate that the model could have significant potential in embedded collision detection systems of micro or small UAVs. [ABSTRACT FROM AUTHOR]

Pitted cones are cone-shaped structures, spanning from meters to kilometers in size, characterized by summit depressions. They are widely distributed on the surface of Mars with various origins, such as rootless cones, mud volcanoes, cinder or scoria cones, tuff rings or cones, pingos, and dirt cones. If the pitted cones identified in southern Utopia Planitia are mud volcanoes, as is speculated, they could be of particular interest due to the fact that mud volcanoes on Earth bring sediments from a depth of meters to kilometers to the surface. In this study, we have investigated the pitted cones near Zhurong rover's landing site in southern Utopia Planitia, utilizing recent images and digital elevation models obtained from the High Resolution Imaging Camera instrument onboard China's Tianwen-1 orbiter. By leveraging the high-resolution images and digital elevation models, we have conducted a geometric measurement to distinguish the origin of pitted cones in the vicinity of the Zhurong rover. The morphological characteristics of these pitted cones indicate an explosive mud volcano origin. These explosive mud volcanoes could have formed by the violent eruption of subsurface overpressurized sediments generated from the combined effect of overburden pressure and anomalous high heat flow. The sediments forming the pitted cones in the northern plains could be the remnants of an ancient ocean. With future in-situ observations of these pitted cones, we hope to gain further insights into the sediments of the putative northern ocean, as well as the physical and chemical properties of the Martian subsurface during the formation of the pitted cones. [ABSTRACT FROM AUTHOR]

Aqueous activities on Mars have gradually declined since the Noachian (>3.7 Ga). Although water can be stored in the subsurface during the latest epochs, geomorphological evidence is still limited. In this study, we used in situ imaging and spectral data acquired by China's Zhurong rover, as well as high‐resolution remote‐sensing data, to investigate the transverse aeolian ridges (TARs) in the Zhurong landing region of Utopia Planitia. A two‐stage evolutionary scenario of the TARs is proposed and polygonal features with hydrated minerals are identified for the first time on the surface of Martian TARs. We discussed the possible formation mechanisms of the polygonal features, and proposed that they could be related to recent aqueous activity and atmosphere‐surface water exchange on Mars, which sheds light on the hydrological cycle of Mars in current cold and dry climate. Plain Language Summary: The history of water on the surface of Mars has been studied for a long time. Since about 3.7 billion years ago, the role of water has gradually declined. Although the existence of subsurface ice on present‐day Mars has been confirmed, evidence for surface water is still limited. Transverse aeolian ridges (TARs), a kind of ripple‐like aeolian landform, are widely distributed on Mars and usually thought to be active within the last ∼3 million years. They are also identified in southern Utopia Planitia, the landing region of China's Mars exploration rover Zhurong. We analyzed the morphology and evolution of the TARs in the Zhurong landing region, and found some polygonal features with hydrated minerals such as gypsum on the surface of the latest‐formed TARs. We discussed the possible origins of these polygons, and proposed that they represent very recent aqueous activity on the Martian surface, which will help us better understand the hydrological cycle on current Mars. Key Points: Morphology and evolution of the transverse aeolian ridges (TARs) in the Zhurong landing region are studiedPolygonal features with hydrated minerals are identified on some of the TARs investigated by the Zhurong roverThe polygons could be related to very recent aqueous activity and atmosphere‐surface water exchange on Mars [ABSTRACT FROM AUTHOR]

Over the past few decades, taxi drivers' income has received extensive attention from scholars. Previous studies have investigated the factors affecting taxi drivers' income from multiple perspectives. However, less attention has been paid to road network topology, which has a direct impact on taxis' operation efficiency and drivers' income. To fill this gap, this paper examines the relationship between taxi drivers' income and urban road network topology; we employed various methods, namely, spatial design network analysis (sDNA), bivariate Moran's I, and geographically weighted regression (GWR). The results show the following. (1) The total order income (TOI) of taxi drivers has a certain degree of positive spatial correlation with closeness and betweenness. (2) The impact of urban road network topology on the average order income (AOI) of taxi drivers is stable. Specifically, closeness and betweenness have significant impacts on the AOI of taxi drivers at the medium and larger scales. (3) Closeness has a negative impact on the AOI of taxi drivers, and betweenness has a positive impact on the AOI of taxi drivers. (4) Compared with betweenness, the impact of closeness on the AOI of taxi drivers is greater and more stable. These findings can provide useful reference values for the development of policies aimed at improving both taxi drivers' income and urban road network efficiency. [ABSTRACT FROM AUTHOR]

We used imaging, laser altimeter and thermal infrared data to map a 0.5 by 0.5° area containing the landing site of the Zhurong rover of the Tianwen‐1 mission. We analyzed the regional topography and thermophysical characteristics, and identified and characterized cones, impact craters, polygonal troughs, ridges and aeolian bedforms. An absolute model age of 757 ± 66 Ma was obtained for the major unit dominating the study area, younger than previous geological mapping results. We propose several targets of high scientific interest for Zhurong and a stratigraphic model composed of five layers (from bottom to top: Noachian basement, Early Hesperian volcanic ridged plains, Vastitas Borealis Formation materials, rocky materials and loose materials). The geomorphic features identified, the proposed stratigraphy and the regional geological evolution scenario set the stage for the Zhurong rover to continue to carry out its exploration of Mars. Plain Language Summary: Tianwen‐1 is China's first independent Mars mission. It consists of an orbiter and a lander and a rover (Zhurong). The Zhurong rover successfully touched down on the surface of Mars on May 15, 2021. The landing site lies in southern Utopia Planitia, in the northern lowlands of Mars. We identified various geomorphologic features within an area of 0.5 by 0.5° centered around the landing site of the Zhurong rover using image, elevation and temperature remote sensing data. We propose a history and geological evolution of the region to set the stage for the Zhurong rover exploration and analysis. Key Points: We conducted detailed geological mapping of the Zhurong landing region on MarsHigh scientific interest targets for Zhurong rover including cones, pitted‐wall craters, aeolian bedforms, polygons, and ridges are proposedA middle Amazonian surface age is suggested and a five‐layer stratigraphic model of the Zhurong landing region is proposed [ABSTRACT FROM AUTHOR]

Background: Laparoscopic approaches for the management of Mirizzi syndrome (MS) are controversial and challenging procedures for high conversion rate. This review aims at evaluating their safety and feasibility. Methods: We reviewed studies related to the laparoscopic approaches for the management of MS with detailed data of articles from January 2009 to December 2019 found in PubMed. Results: From 63 articles, we reviewed 17 articles detailing laparoscopic approaches for MS. There were 857 patients with MS; 432 of which were identified from 73,842 patients underwent cholecystectomy. Laparoscopic approaches were attempted in 440 patients and were successful in 290. The conversion rate was 34.09%. Various methods including laparoscopic cholecystectomy, laparoscopic subtotal cholecystectomy, laparoscopic common bile duct exploration (LCBDE) and (LTCBDE) were performed. The preoperative diagnosis of MS was made in 338 of 500 patients (67.60%). The mean operating time ranged from 49.7 ± 27.5 min to 270.5 ± 65.5 min, and the mean intraoperative bleeding varied from 21.1 ± 15.9 ml to 162.81 ± 40.83 ml. The mean hospital stay varied from 4.5 ± 3.7 to 7.21 ± 1.61 days. Postoperative complications occurred in 27 patients. Conclusions: Various laparoscopic approaches are safe and feasible for the treatment of MS in the hands of experienced laparoscopic surgeons, especially for type I and II of Csendes classification. Definitive preoperative diagnosis and earlier management are essential. [ABSTRACT FROM AUTHOR]

Hellas basin is the largest and deepest depositional sink in the southern highlands of Mars. The region to the north of the Hellas basin is characterized by a variety of fan-shaped sedimentary deposits, which record the history of aqueous activities and climate change. We newly identified 20 potential deltas, 134 alluvial fans, 42 debris flows, 137 glacier-related fans, and 121 other fan-shaped landforms including landslides. The accumulation of liquid water-related fans along the northeastern flanks of the Hellas basin is likely controlled by elevation. The focus of this study is the potential deltas and alluvial fans for which detailed geomorphic analysis was carried out. The sediment fans sit mainly within closed basins and their feeder valleys are immature, indicating a short-lived activity of water. We observed two cases of a younger fan system creating an incision through an older sediment fan, indicating a punctuated reduction in the activity of water, in which the duration of the interfluvial period was assessed. We dated the sediment fans and found that they were mainly formed in the Hesperian and Early Amazonian and underwent glacial resurfacing around 700 Myr ago. Only a few fans formed in the Late Noachian were identified. Based on our observations, we submitted snowfall as the main source of water for these sedimentary fans although, as seen in the two cases of alluvial fans, a few of them could also have been fed by small-scale glacial melt. Both water sources supported cold and dry spells. We concluded that the fans record a persistence of water/ice activity until the Middle Amazonian in Martian history. • Mapping, morphologic and genesis studies of fan-shaped deposits were conducted. • Sediment fans were mainly formed in the Hesperian and Early Amazonian periods. • Sediment fans record a short-lived and two-stage decreasing activity of water. • Snowpack melting contributes to forming most sediment fans under a cold climate. • Younger alluvial fans formed by small-scale glacial melt were found. [ABSTRACT FROM AUTHOR]

Lava tubes are widely distributed in volcanic fields on a planetary surface and they are important means of lava transportation. We have identified 38 sinuous ridges with a lava-tube origin in southeast Tharsis. The lengths vary between ~ 14 and ~ 740 km, and most of them occur in areas with slopes < 0.3°. We analyzed their geomorphology in detail with CTX (Context Camera) and HiRISE (High Resolution Imaging Science Experiment) images and DTM (digital terrain model) derived from them. We identified three cross-sectional shapes of these sinuous ridges: round-crested, double-ridged, and flat-crested and described features associated with the lava tubes, including branches, axial cracks, collapsed pits, breakout lobes, and tube-fed lava deltas. Age determination results showed that most of the lava tubes formed in Late Hesperian and were active until the Hesperian-Amazonian boundary. We proposed that these lava tubes formed at relatively low local flow rate, low lava viscosity, and sustained magma supply during a long period. Besides, lava flow inflation is also important in the formation of the ridge-like lava tubes and some associated features. These lava tubes provide efficient lateral pathways for magma transportation over the relatively low topographic slopes in southeast Tharsis, and they are important for the formation of long lava flows in this region. The findings of this study provide an alternative formation mechanism for sinuous ridges on the martian surface. [ABSTRACT FROM AUTHOR]

Autoimmune diseases represent a class of over 80 illnesses with high incidence and prevalence and share a common pathogenesis of immune system disorders and self-attack. Over the past decade, extensive studies have demonstrated that imbalance of cGAS-STING mediated innate immune signaling is closely involved in autoimmune diseases. Over-activation of cGAS-STING pathway by mutations of STING or several exonucleases can cause accumulation of interferon and systemic inflammation. Therefore, suppression of the upregulated cGAS-STING pathway holds great potential in the treatment of human inflammatory and autoimmune diseases. Inhibitors targeting cGAS, STING and the downstream factors have been developed and pharmacologically evaluated recently. Herein, we summarize the recent advance on development of small molecular inhibitors targeting the key effectors in cGAS-STING axis as promising treatment for autoimmune diseases. [Display omitted] • Autoimmune diseases represent a class of over 80 illnesses with high incidence. • Over-activation of cGAS-STING pathway is implicated in autoimmune diseases. • Mice disease models were built bearing mutations of STING or several exonucleases. • Inhibitors targeting cGAS, STING and the downstream factors have been developed. • Some of these inhibitors showed efficacy in cells and in mice models. [ABSTRACT FROM AUTHOR]

The NOD-like receptor family pyrin domain-containing protein 3 (NLRP3) is a key cytosolic pattern recognition receptor that senses diverse pathogen- and host-originated threat signals. Aberrant activation of NLRP3 inflammasomes is closely associated with the pathogenesis of various complex inflammatory diseases. Nevertheless, the detailed regulation mechanism of NLRP3 inflammasome and its pathogenic roles in the inflammation progression remain to be fully elucidated. Fluorescent imaging with small molecule probe can provide valuable visualization information on the expression, occupancy and bio-distribution of target protein. Herein, we reported a series of diarylsulfonylurea NLRP3 fluorescent inhibitors bearing an amino benzodiazole fluorophore. Compared to the previously reported NLRP3 fluorescent probes, these inhibitors are more structurally concise and membrane permeable due to no additionally appended fluorophore via a linker. Among this series, compound 13a exhibited the most potent cellular NLRP3 inhibitory effect with an IC 50 value of 49 nM, and significantly suppressed LPS/Nigericin-induced secretion of active caspase-1 and mature IL-1 β in a dose-dependent manner to block the activation of NLRP3 inflammasome. Meanwhile, this new probe exhibited promising fluorescent properties for specifically detecting and imaging the LPS-induced or constitutively expressed NLRP3 proteins in RAW264.7 cells. Collectively, probe 13a is a potent NLRP3 fluorescent inhibitor with cellular NLRP3 imaging ability, which is useful for NLRP3 inhibitor screening and related mechanism study. [Display omitted] • A series of new NLRP3 fluorescent inhibitors was developed. • 13a suppressed cellular NLRP3 inflammasome activation with IC 50 of 49 nM. • 13a could specifically detect and image cellular NLRP3 in RAW264.7 cells. [ABSTRACT FROM AUTHOR]

A catalytic asymmetric carbonyl–ene reaction of β,γ-unsaturated α-ketoesters with 5-methyleneoxazolines was accomplished. The process was based on the utilization of a chiral N,N′-dioxide/MgII catalyst, providing the desired products with excellent outcomes (up to 99% yield, ＞99% ee) under mild reaction conditions. Based on the experimental investigations and previous reports, a possible transition state was proposed. [ABSTRACT FROM AUTHOR]

Novel band gap-tunable K–Na co-doped graphitic carbon nitride was prepared by molten salt method using melamine, KCl, and NaCl as precursor. X-ray diffraction (XRD), N 2 adsorption, Scanning electron microscope (SEM), UV–vis spectroscopy, Photoluminescence (PL), and X-ray photoelectron spectroscopy (XPS) were used to characterize the prepared catalysts. The CB and VB potentials of graphitic carbon nitride could be tuned from −1.09 and +1.55 eV to −0.29 and +2.25 eV by controlling the weight ratio of eutectic salts to melamine. Besides, ions doping inhibited the crystal growth of graphitic carbon nitride, enhanced the surface area, and increased the separation rate of photogenerated electrons and holes. The visible-light-driven Rhodamine B (RhB) photodegradation and mineralization performances were significantly improved after K–Na co-doping. [ABSTRACT FROM AUTHOR]

A highly enantioselective Mannich reaction of silyl ketene imines with isatin-derived ketimines has been realized by using a chiral N, N′-dioxide/ZnII catalyst. A variety of β-amino nitriles containing congested vicinal tetrasubstituted stereocenters were obtained with excellent outcomes (up to 98 % yield, >19:1 d.r. and 99 % ee). Based on the experimental investigations, a possible transition state has been proposed to explain the origin of the asymmetric induction. [ABSTRACT FROM AUTHOR]

A highly enantioselective Mannich reaction of silyl ketene imines with isatin-derived ketimines has been realized by using a chiral N, N′-dioxide/ZnII catalyst. A variety of β-amino nitriles containing congested vicinal tetrasubstituted stereocenters were obtained with excellent outcomes (up to 98 % yield, >19:1 d.r. and 99 % ee). Based on the experimental investigations, a possible transition state has been proposed to explain the origin of the asymmetric induction. [ABSTRACT FROM AUTHOR]

Fluvial activities play important roles in the geologic evolution of early Mars. As one of the most ancient fluvial features on Mars, the widely distributed valley networks (VNs) provide clues for understanding the early martian climate. Our study focuses on the morphological and hydrological features of VNs around the Huygens basin in the ancient southern highland. A total of 198 VNs are identified in the Huygens region with a total length of 23,991.6 km, among which 83 VNs are firstly identified. VNs possess drainage patterns of dendritic to parallel, and show average stream order of 2.45 with a maximum of 5, suggesting a simple branching morphology. Sinuosity indexes of mainstreams range from 1.02 to 1.98 with an average of 1.15, exhibiting a straight to winding form. Two types of VN channels are observed with distinct elevational distribution, headwater morphology, and longitudinal profile shape, and are considered to be sapping-related and surface runoff-related, respectively. Age estimations from crater size-frequency distribution measurements suggest that VN activities at the basin rim mainly started around the Noachian/Hesperian boundary at ~3.7 Ga, and decayed near the Early/Late Hesperian boundary. VNs at the basin floor show a younger age of ~3.5 Ga, which supports a potential short-lived lake inside the basin during the Noachian-Hesperian transition. A combined effect of rainfall and groundwater is considered as the dominant water sources of VNs in the Huygens region, with the climate condition characterized by transient warm and arid-semiarid periods under a possibly cold and arid environment. • Detailed mapping and morphological study of Huygens valley networks are conducted. • Regional valley network activities occur intermittently over ~3.7–~3.3 Ga. • A combined water source of limited rainfall and groundwater is favored. • Transient warm and arid-semiarid periods exist around Noachian/Hesperian boundary. [ABSTRACT FROM AUTHOR]

A range of β‐amino nitriles containing contiguous tertiary and quaternary stereogenic carbon centers were synthesized by using the title reaction. The reaction was catalyzed by a chiral N,N′‐dioxide scandium(III) complex under mild reaction conditions. Based on experimental investigations, a possible transition state has been proposed to explain the origin of asymmetric inductivity. [ABSTRACT FROM AUTHOR]

Direkt benachbarte tertiäre und quartäre Kohlenstoffstereozentren zeichnen die Produkte der Titelreaktion aus, die unter milden Bedingungen verläuft und durch einen chiralen N,N′ ‐ Dioxid ‐ ScIII ‐ Komplex katalysiert wird. Auf der Grundlage experimenteller Untersuchungen wird ein möglicher Übergangszustand vorgeschlagen, der die asymmetrische Induktion erklärt. [ABSTRACT FROM AUTHOR]

The N,N′-dioxide-Ni(II) complex has been developed for the asymmetric Mukaiyama aldol reaction between glyoxal derivatives and enolsilane which produced the 2-hydroxy-1,4-dicarbonyl compounds in moderate to high yields (up to 95%) with excellent enantioselectivities (up to 95% ee). Based on the configuration of the product and X-ray structure of the catalyst, a possible transition state was proposed to explain the mechanism of the reaction. [ABSTRACT FROM AUTHOR]

Zephyria Tholus has been proposed to be a composite volcano, however, detailed geomorphological study was not carried out due to limited high-resolution remote sensing data. Here we use MOLA, THEMIS, CTX and HiRISE data to conduct topographical and geomorphological analysis of Zephyria Tholus. We identify extensive valleys and troughs on the flank, which are sector collapse or glacio-fluvial in origin. The valleys and troughs indicate coexistence of different erosion resistance materials, along with the observed solid lava outcrops. There are also layered materials identified on the wall of the largest valley. In addition, perched craters are identified on the top depression and flanks of Zephyria Tholus, indicating the presence of ice-rich layer. We conducted crater size-frequency distribution of the caldera and found the absolute model age is 3.74 (+0.03, −0.04) Ga. The geomorphology evidence and chronology result support the composite volcano nature of Zephyria Tholus, and indicate the magma volatile content in the Aeolis region in Noachian is more than 0.15 wt% if the atmosphere paleo-pressure was similar to present Mars. [ABSTRACT FROM AUTHOR]

Curvilinear ridges are extensively identified on the surface of terrestrial planets and can be formed by volcanic, glacial, eolian, or fluvial processes. In the Qaidam Basin, NW China, a set of unique curvilinear ridges that have similar appearances as inverted channels but are dominated by sand deposits in their interiors has been identified. To reveal its formation mechanism, we analyzed their topography, morphology, outcrop and profile characteristics by remote-sensing and field surveys. We proposed that these curvilinear ridges are "sand-infilled inverted channels" formed by episodic wet and dry climate transitions. Considering the long history of Mars, some martian curvilinear ridges could also be formed by this mechanism, thus we should be more cautious in the identification and analysis of martian inverted channels. In addition, the occurrence of sand-infilled inverted channels on Mars may imply that the martian climate change from warm and wet to cold and dry has been gradual rather than abrupt, once this kind of inverted channels found on Mars. • Curvilinear ridges infilled with eolian sand are identified in the Qaidam Basin. • A sand-infilled inverted channel origin is proposed for the curvilinear ridges. • Curvilinear ridges of similar origin could be found on Mars. • Paleodischarge estimation of inverted channels should be cautious. • The climate change from warm and wet to cold and dry could be episodic on Mars. [ABSTRACT FROM AUTHOR]

Yardangs, as typical aeolian landforms, are extensively identified in arid/hyper-arid areas on Earth and other terrestrial bodies. In this review, based on analyses of morphology, distribution, age, climate, and geologic condition of yardangs worldwide, we (1) assess the impacts of various controlling factors on yardang development to generalize a model based on morphology; (2) illustrate the climate-driven mechanism for yardangs; (3) propose a geomorphological evolutionary model of yardang fields; and (4) discuss potential implications of the above two models of yardang evolution on Earth to Mars. It is demonstrated that both deflation and abrasion work on yardang development, and it is the lithology to determine which one will be more effective. In addition, the wind action dominates the general aerodynamic form of yardangs, while non-aeolian factors account for the diversity in yardang morphology. Thus, a model including four stages and initiating mechanisms is generalized for yardang processes, from initiation to demise. The synthetic analyses of meteorological data, chronology, and paleoclimatic proxies show that yardang development is mostly controlled by westerlies, and would be accelerated during glacial periods and interrupted by lake formation during interglacial periods due to dry-humid fluctuations and changes in atmospheric circulation, driven by variations in solar radiation at orbital scales. This leads to the zonal distributions of yardangs near 30° in both hemispheres. Depressions would be created or enlarged in yardang fields during glacial period, along with activities of dust release and transport, leading to aeolian deposition (e.g. loess) downwind. The depressions, then, could be turned into lakes during wet phase of interglacial period and evolved into new yardangs in the following glacial period due to wind erosion. This climate-controlled geomorphological process under glacial-interglacial cycles suggests that high accumulation rate in sediments from enclosed inland basins (e.g. the Qaidam Basin) doesn't mean high-resolution climatic record due to the hiatus by wind erosion, indicating the significance of robust chronology establishment before any climatic correlation. Under the rules of Earth-based yardang evolution, it is potential to identify the specific level of development and explore the geomorphological processes as well as the climatic background for yardangs on Mars. • A morphological model is generalized based on yardang processes and controllers. • Driven by orbital climatic change, westerlies account for most yardang development. • A model of yardang fields reveals alternation of yardangs and lakes chronologically. • High accumulation rate does not mean high resolution in sediments of inland basins. • Earth yardang model is helpful to identify Martian yardang and its related climate. [ABSTRACT FROM AUTHOR]

• A central caldera, radial/concentric distributed domes and faults exist in Gardner. • Sill intrusions or large conduit solidification happened beneath Gardner. • Gardner experienced four periods of magma eruptions from 3.90 to 2.96 Ga. • Gardner is the largest central-vent volcano identified so far on the Moon. • Gardner volcano is an important source region for basalts in Mare Tranquillitatis. Large shield-building volcanic structures (>30 km) with central vents are rare on the Moon. The most popular candidate targets of lunar large shield volcanoes are volcanic complexes on the lunar nearside within the compositionally evolved Procellarum KREEP terrane (PKT). However, there is a unique mass concentrated volcanic complex not within the PKT, namely Gardner (16.1°N, 34.1°E, ∼70 km in diameter) on the northern edge of Mare Tranquillitatis, whose origin is enigmatic. Here we use multi-source remote-sensing data to assess its morphology, composition and stratigraphy to better understand its formation and evolution. Results show that domes, sinuous rilles, and an irregular depression exist in this region. Gardner has experienced four stages of volcanic activities with absolute model ages from 3.90 to 2.96 Ga, contemporaneous with the main volcanic activity periods of the lunar nearside. An area with relatively low albedo, high FeO and TiO 2 contents, low rock abundances, and young surface age is identified in the southeast part of the irregular depression at the summit of the plateau, which could have been the result of a long-lived eruptive center. Quasi-circular positive Bouguer-gravity anomaly suggests either sill/laccolith intrusions or large conduit solidifications underneath this area, which could be related to its surrounding radially distributed lava domes, wrinkle ridges and faults. We conclude that Gardner is the largest central-vent volcano identified so far on the Moon, and it provides an essentially new perspective and supplement for the knowledge of the lunar nearside volcanism. [ABSTRACT FROM AUTHOR]

Impact craters are extensively researched geological features that contribute to various aspects of lunar science, such as evaluating the model age, regolith thickness, etc. The method for identifying impact craters has gradually transitioned from manual counting to automated identification. Automatic crater detection based on the digital elevation model (DEM) is commonly used to detect larger craters. However, using only DEM has limitations in discerning smaller craters (diameter < ~1 km). This study utilizes an improved Faster R-CNN algorithm and the Kaguya Terrain Camera (TC) morning map to detect small impact craters in the Chang'e-5 (CE-5) landing site. It uses model fusion to improve the precision of small crater identification. The results show a recall rate of 96.33% and a precision value of 90.19% for craters with diameters exceeding 200 m. The model found a total of 187,101 impact craters in the CE-5 region. The spatial distribution density of impact craters with diameters ranging from 100 m to 200 m is approximately 2.5706/km2. For craters with diameters ranging from 200 m to 1 km, the average spatial distribution density is about 0.9016/km2. By the unbiased impact crater density of chronological analysis, the model age of the Im2 and Em4 geological units in the CE-5 region is 3.78 Ga and 2.07 Ga, respectively. [ABSTRACT FROM AUTHOR]

When discussing the influence of the built environment on taxi travel demand, few studies have considered the effect of the modifiable areal unit problem (MAUP) or the influence of the "5D" dimensions of the built environment (It refers to the consideration of the built environment from five dimensions of density, diversity, design, destination accessibility and distance to transit.) on taxi travel demand. Moreover, discussion of the nonlinear and linear relationships between taxi demand and environment variables is also lacking. To address these gaps, we constructed a "5D" dimension index system of built environment variables. The influence of the MAUP on the model results was discussed using the optimal parameter-based geographical detector (OPGD) model, and the optimal spatial analysis unit was selected. The OPGD and multiscale geographically weighted regression (MGWR) models were used to reveal the influence of different dimensions of the built environment on taxi travel demand from global and local perspectives, respectively. Finally, the central urban area of Xi'an was analyzed as an example. The results show the following: (1) Most built environment variables are sensitive to the influence of MAUP. (2) It is better to divide the space into regular hexagons than squares, and the optimal spatial analysis unit in this study is a regular hexagon grid with sides of 900m. (3) From a global perspective, the distance to the city center, commercial residence POI density, transportation facility POI density, and population density have the greatest influence on the demand for taxi travel. (4) From a local perspective, the MGWR model considering spatial heterogeneity and scale differences is superior to the GWR model, and the influence of built environment variables exhibited spatial heterogeneity. The proposed optimal spatial analysis unit can provide a basis for taxi demand forecasting and scheduling. This study provides a reference for urban planners and traffic managers to offer optimization strategies related to the built environment, promote healthy development of the taxi industry, and solve the problems of the urban transportation system. [ABSTRACT FROM AUTHOR]

Moreover, the simple α-keto ester (X) can also be converted to the corresponding product (XI). [ABSTRACT FROM AUTHOR]

A highly enantioselective Mannich reaction of silyl ketene imines with isatin-derived ketimines is realized by using a chiral N,N′-dioxide/ZnII catalyst. [ABSTRACT FROM AUTHOR]

This new process proceeds under mild conditions, exhibits a broad substrate scope and functional-group tolerance, and features good air and moisture tolerance. [ABSTRACT FROM AUTHOR]

A new catalyst system allows the diastereo- and enantioselective synthesis of various title compounds, precursors of optically active diamines and β-amino acids. [ABSTRACT FROM AUTHOR]

The Chang'e-3 (CE-3) spacecraft successfully landed on one of the youngest mare surfaces on the Moon in December 2013. The Yutu rover carried by CE-3 was equipped with a radar system that could reveal subsurface structures in unprecedented details, which would facilitate understanding regional and global evolutionary history of the Moon. Based on regional geology, cratering scaling, and morphological study, here we quantify the subsurface structures of the landing site using high-resolution orbital and in-situ imagery data. Three layers of lunar regolith, two layers of basalt units, and one layer of ejecta deposits are recognized at the subsurface of the landing site, and their thicknesses are deduced based on the imagery data. These results could serve as essential references for the on-going interpretation of the CE-3 radar data. The ability to validate our theoretical subsurface structure using CE-3 in-situ radar observations will improve the methods for quantifying lunar subsurface structure using crater morphologies and scaling. [ABSTRACT FROM AUTHOR]

There are many buried craters on Mars invisible in imaging or topographic data; however, the residual gravity anomaly separated from the Mars Bouguer gravity anomaly by minimum curvature separation method can reveal these buried craters. In our research, gravity separation results exposed 39 residual gravity anomaly highs (RGAHs), which may represent deeply buried impact craters with 300–500 ​km diameter. The RGAHs are widely distributed across the surface of Mars, but are especially concentrated in volcanic areas like Tharsis and Elysium, which indicates that there might be more craters buried in these regions. Older craters in volcanic regions were likely buried by subsequent volcanism coming from surrounding volcanoes, so the retention age of craters in all areas where RGAHs are located will be older than reported in the existing research based on topographic data alone. This study will help improve the chronological model of Mars. • The impact craters of Mars with diameter of 300–500 km appear central positive residual gravity anomalies. • The gravity separation results exposed 39 anomaly highs, that is inferred to be buried impact craters. • The most RGAHs are concentrated in volcanic areas just like Tharsis and Elysium. [ABSTRACT FROM AUTHOR]

The Sinus Iridum region is one of the important candidate landing areas for the future Chinese lunar robotic and human missions. Considering its flat topography, abundant geomorphic features and complex evolutionary history, this region shows great significance to both lunar science and landing exploration, including powered descent, surface trafficability and in-situ exploration. First, we use Lunar Reconnaissance Orbiter (LRO) Altimeter (LOLA) and Camera (LROC) data to characterize regional topographic and geomorphological features within Sinus Iridum, e.g., wrinkle ridges and sinuous rilles. Then, we deduce the iron and titanium content for the mare surface using the Clementine ultraviolet–visible (UVVIS) data and generate mineral absorption features using the Chandrayaan-1 Moon Mineralogy Mapper (M 3 ) spectrometer data. Later, we date the mare surface using crater size-frequency distribution (CSFD) method. CSFD measurements show that this region has experienced four major lava infilling events with model ages ranging from 3.32 Ga to 2.50 Ga. The regional magmatic activities evolved from Imbrian-aged low-titanium to Eratosthenian-aged medium-titanium. The inner Sinus Iridum is mainly composed of pyroxene-rich basalts with olivine abundance increasing with time, while the surrounding highlands have a feldspar-dominated composition. In the northern wall of Sinus Iridum, some potential olivine-rich materials directly excavated from the lunar mantle are visible. The Sinus Iridum region is an ideal target for future landing exploration, we propose two candidate landing sites for the future Chinese robotic and human missions. [ABSTRACT FROM AUTHOR]

The Elysium Rise in the Martian northern hemisphere is the second largest volcanic province on Mars. To understand the volcanic activity in the Elysium Rise, the gravitational characteristics of this area were studied using the Bouguer gravity data derived from Goddard Mars Model-3 (GMM-3). The Bouguer gravity anomaly in the Elysium Rise was separated into regional fields and residual fields and the subsurface density profiles were obtained by a three-dimensional density inversion. The different anomaly features of the large volcanoes in the Elysium Rise were exhibited by the separation and density inversion results. Elysium Mons is characterized by a positive residual gravity anomaly surrounded by an annular negative anomaly, which possibly results from the volcano loading on a lithosphere plate. Albor Tholus has a positive gravity anomaly but with no obvious annular negative anomalies, which may result from the relatively small mass deficit generated by the eruption of Albor Tholus, unlike the Elysium Mons. In addition, the residual field shows prominent positive gravity anomalies with 150 km wide, centred at 157.2°E, 12.1°N, which could possibly be a hidden impact crater with an untraceable surface morphology or topography. Our study reveals the subsurface mass source distributions and structures of the Elysium volcanoes, providing a new method to understand the tectonic framework of the Martian subsurface through the study of gravity. • The cross-correlation method can separate local shallow anomalies in the time domain by controlling a single parameter. • Different residual gravity signatures between Elysium and Albor possibly result from their volcano loadings on a lithosphere plate. • An additional anomaly signature located in the southeast of Elysium Rise indicates the possible existence of a buried basin. [ABSTRACT FROM AUTHOR]

Phosphine‐mediated deoxygenative nucleophilic substitutions, such as the Mitsunobu reaction, are of great importance in organic synthesis. However, the conventional protocols require stoichiometric oxidants to trigger the formation of the oxyphosphonium intermediates for the subsequent nucleophilic additions. Through dual catalysis of photoredox and cobaloxime, we realized a radical strategy for the catalytic formation of acyloxyphosphonium ions that enables direct amidation. The deoxygenative protocol exhibits a broad scope and has been used in the late‐stage amidation of drug molecules. In addition to batch reactions, a continuous‐flow reactor was developed, enabling rapid peptide synthesis on gram scale. The successful assembly of a tetrapeptide on the solid support further demonstrated the versatility of this photocatalytic system. Moreover, experimental and computational studies are consistent with the hypothesis of acyloxyphosphonium ions being formed as the key intermediates. [ABSTRACT FROM AUTHOR]

Phosphine‐mediated deoxygenative nucleophilic substitutions, such as the Mitsunobu reaction, are of great importance in organic synthesis. However, the conventional protocols require stoichiometric oxidants to trigger the formation of the oxyphosphonium intermediates for the subsequent nucleophilic additions. Through dual catalysis of photoredox and cobaloxime, we realized a radical strategy for the catalytic formation of acyloxyphosphonium ions that enables direct amidation. The deoxygenative protocol exhibits a broad scope and has been used in the late‐stage amidation of drug molecules. In addition to batch reactions, a continuous‐flow reactor was developed, enabling rapid peptide synthesis on gram scale. The successful assembly of a tetrapeptide on the solid support further demonstrated the versatility of this photocatalytic system. Moreover, experimental and computational studies are consistent with the hypothesis of acyloxyphosphonium ions being formed as the key intermediates. [ABSTRACT FROM AUTHOR]

Lunar volcanic domes are essential windows into the local magmatic activities on the Moon. Classification of domes is a useful way to figure out the relationship between dome appearances and formation processes. Previous studies of dome classification were manually or semi-automatically carried out either qualitatively or quantitively. We applied an unsupervised machine-learning method to domes that are annularly or radially distributed around Gardner, a unique central-vent volcano located in the northern part of the Mare Tranquillitatis. High-resolution lunar imaging and spectral data were used to extract morphometric and spectral properties of domes in both the Gardner volcano and its surrounding region in the Mare Tranquillitatis. An integrated robust Fuzzy C-Means clustering algorithm was performed on 120 combinations of five morphometric (diameter, area, height, surface volume, and slope) and two elemental features (FeO and TiO2 contents) to find the optimum combination. Rheological features of domes and their dike formation parameters were calculated for dome-forming lava explanations. Results show that diameter, area, surface volume, and slope are the selected optimum features for dome clustering. 54 studied domes can be grouped into four dome clusters (DC1 to DC4). DC1 domes are relatively small, steep, and close to the Gardner volcano, with forming lavas of high viscosities and low effusion rates, representing the latest Eratosthenian dome formation stage of the Gardner volcano. Domes of DC2 to DC4 are relatively large, smooth, and widely distributed, with forming lavas of low viscosities and high effusion rates, representing magmatic activities varying from Imbrian to Eratosthenian in the northern Mare Tranquillitatis. The integrated algorithm provides a new and independent way to figure out the representative properties of lunar domes and helps us further clarify the relationship between dome clusters and local magma activities of the Moon. [ABSTRACT FROM AUTHOR]

As an important service industry in cities, taxis provide people with an all-weather travel mode. And its demand is greatly affected by the internal functions of the city. It is very important to understand the relationship between the mixed degree of urban internal functions and the residents' taxi travel demand to alleviate traffic congestion and formulate corresponding urban traffic strategies. This paper combined two heterogeneous data in the main urban area of Xi'an, urban points of interest (POIs) and taxi GPS. Firstly, a spatial information entropy model was constructed to quantitatively evaluate the mixed degree of functions in different spaces within the city. Secondly, the kernel density estimation method was used to analyze the spatial distribution evolution characteristics of residents' taxi travel demand. A geographically weighted regression (GWR) model was further used to study the spatial and temporal influences of the mixed degree of urban internal functions on taxi travel demand. Results indicate that there is an obvious spatiotemporal pattern in the impact of the mixed degree of urban functions on taxi travel demand. And the GWR model is used to study the impact is superior to the ordinary least squares (OLS). In more developed areas, improving the mixed degree of urban functions will be more attractive than backward areas. It is also found that although the single function of the city has an impact on the taxi travel demand, the result of the single function is not ideal. This study can provide a reference for the optimal combination of basic units of urban space in urban planning, promote the balance of supply and demand of urban taxis, rationalize urban taxis' operation and allocation, and solve the problems of urban transportation systems. [ABSTRACT FROM AUTHOR]

• In-situ zircon neoblasts within reidite lamellae record the onset of granular process. • Systematic orientations of granules are controlled by reversion from reidite. • Zirconia in reidite is related to dissociation process during shock release. Zircon with granular texture from hypervelocity impact structures can be used to estimate the thermodynamic conditions of impact processes, including pressure and temperature, and in some cases the timing of impact events via U-Pb geochronology. However, two disparate formation models have been proposed to explain the occurrence of zircon neoblasts that preserve systematic orientation relations; one involves zircon-reidite phase transformations (FRIGN zircon), whereas the other features melting and thermal dissociation of zircon in the absence of reidite. Distinguishing between these models is hampered by the lack of observational constraints on the intermediate transformation steps at nanoscale, and what processes give rise to observed systematic orientation relations among zircon neoblasts. Here we report new analyses of reidite-bearing and granular zircons from peak ring core samples of the Chicxulub impact structure using nanoscale methods. We describe lamellar and lense-like reidite habits associated with reidite twins in shocked zircon from impact melt-bearing breccia, along with the first observation of nanoscale zircon granules forming locally within preserved reidite lamellae. The crystallographic orientation of the zircon nano-granules matches the orientations predicted by the FRIGN zircon model, confirming they formed directly by solid-state reversion of reidite to zircon, and represent the earliest stages of the formation of granular zircon. Minor occurrences of baddeleyite at the interface of reidite and neoblastic zircon domains suggest that the reversion of reidite to zircon can occur together with local ZrSiO 4 dissociation driven either by the loss of SiO 2 , which creates excess zirconia, or by local thermal dissociation of reidite. Other partially- and fully-granular zircon grains from the same impact melt-bearing breccia also preserve systematic orientation relationships among zircon neoblasts, consistent with having transformed directly from reidite. The observation that zircon neoblasts maintain systematic orientations from nanoscale to microscale in granular zircon supports the idea that neoblast orientations are encoded at the nucleation stage via solid state phase transformation. Observations in this study provide direct evidence to explain the nature of systematic high-pressure phase transitions involving zircon and have implications for unraveling the pressure-temperature history of zircon phase transitions in large impacts on Earth or other planetary bodies. [ABSTRACT FROM AUTHOR]

The lunar regolith layer preserves abundant information on the internal properties of the Moon as well as the space-surface interactions. By gardening and overturning through time, the regolith layer is heterogenous and soils from different depths could record the complex evolution history of the Moon. Chang'e-5 (CE-5) successfully returned scooped samples and drilled samples from the northeastern Oceanus Procellarum of the Moon. In this study, one scooped sample (0–3 cm depth, S0) and two drilled samples (~10 cm depth, S10; and ~ 65 cm depth, S65) were employed to analyze their granulometry and mineralogy by micro Raman spectroscopy. The grain size increases with depth, and the median grain size of S0, S10, and S65 are Φ5.45 (30.2 μm), Φ4.47 (45.0 μm), and Φ3.37 (96.4 μm), respectively. Their mineral types and contents are pyroxene (33.4–40.5 vol%), plagioclase (30.4–33.8 vol%), olivine (9.0–13.1 vol%), glass (6.9–10.7 vol%), Fe Ti oxide (6.7–7.5 vol%), cristobalite (0.2–3.8 vol%), quartz (0.4–0.9 vol%), and phosphate (0.2–0.6 vol%). The size-dependent mineral modes reveal the relationship between grain size and mineralogy. The mineral modal abundances of 3 soil samples at different depths are roughly similar to that of CE-5 basalts. Raman peak position of quartz may record a peak shock pressure of 31.4 GPa. 5–9 vol% plagioclase amorphization reflects that at least 2–9% exogenous materials in CE-5 soil samples are ejected from craters with diameters larger than 3 km located beyond 50 km from the landing site. • Granulometry and mineralogy of CE-5 soil samples from three different depths were analyzed by micro-laser Raman spectroscopy. • The grain size distribution of CE-5 lunar soil exhibits an increasing trend with depth. • The mineral constituents of the soil samples are consistent throughout various depths. • Highly shocked materials were observed, including shocked quartz, quartz glass, and plagioclase glass. • Exogenous materials account for >2–9% of the CE-5 samples. [ABSTRACT FROM AUTHOR]

An efficient catalytic enantioselective aza-ene-type reaction of glyoxal derivatives with enamides and enecarbamates has been realized using a nickel(ii)-N,N′-dioxide complex as the catalyst. [ABSTRACT FROM AUTHOR]

The Von Kármán Crater, within the South Pole-Aitken (SPA) Basin, is the landing site of China's Chang'E-4 mission. To complement the in situ exploration mission and provide initial subsurface interpretation, we applied a 3D density inversion using the Gravity Recovery and Interior Laboratory (GRAIL) gravity data. We constrain our inversion method using known geological and geophysical lunar parameters to reduce the non-uniqueness associated with gravity inversion. The 3D density models reveal vertical and lateral density variations, 2600–3200 kg/m3, assigned to the changing porosity beneath the Von Kármán Crater. We also identify two mass excess anomalies in the crust with a steep density contrast of 150 kg/m3, which were suggested to have been caused by multiple impact cratering. The anomalies from recovered near surface density models, together with the gravity derivative maps extending to the lower crust, are consistent with surface geological manifestation of excavated mantle materials from remote sensing studies. Therefore, we suggest that the density distribution of the Von Kármán Crater indicates multiple episodes of impact cratering that resulted in formation and destruction of ancient craters, with crustal reworking and excavation of mantle materials. [ABSTRACT FROM AUTHOR]

The recent developments in asymmetric A3 (aldehyde–alkyne–amine) coupling has been summarized in this review. Several interesting modifications of the ligands enabled the highly enantioselective synthesis of chiral propargylamines, which are further used in the construction of nitrogen-containing chiral building blocks. [ABSTRACT FROM AUTHOR]

[Display omitted] An N -heterocyclic carbene catalyzed benzylic C–H acylation of o -alkyl benzamides and cascade cyclization is developed through a radical-mediated 1,5-hydrogen atom transfer (HAT) mechanism. Different from photoredox catalysis, this light-free approach enables the generation of amidyl radicals through single-electron transfer (SET) with Breslow enolates. The mild process tolerates most common functional groups and delivers a variety of dihydroisoquinolinones in moderate to high yields. The electrochemical character of the aryloxyamide is consistent with the hypothesis of ground-state SET and a plausible mechanism for the organocatalytic transformation is proposed. [ABSTRACT FROM AUTHOR]

Remote sensing observations and rover missions have documented the presence of playas, salts, and wind erosion landforms of lacustrine sediments on Mars. All of these observations suggest Mars was aqueous in its early history. However, abundant questions remain: How wet was the environment, what were the properties of the liquids and the possibility of ancient habitability, and what kinds of geological processes shaped the present landforms? To explore these unknowns, analogue studies can play a key role. In this contribution, we introduce the Qaidam Basin, Tibetan Plateau, northwestern China as a new and unique analogue site for studying the past aqueous and present arid environments of Mars. The Qaidam Basin, the highest and one of the largest and driest deserts on Earth, is located in a dry, cold, and high UV environment, similar to the surface of Mars. We demonstrate a variety of landforms and also their counterparts on Mars, which include aeolian dunes and yardangs, polygons, gullies, valleys, and fluvial fans. In the Qaidam Basin, various environmental regimes for the formation of linear and asymmetric barchans have been described. Saline lakes and playas representing different stages of lake evolution in arid environment are also present in the Qaidam Basin and provide promising cases for studying the habitability in Mars-like environments. Results for microorganism isolation suggest that halophiles are the most important fraction in the hypersaline sediments and this may shed light on studying present Martian habitability. Moreover, the remote but ready accessibility of the Qaidam Basin make it a potential site for engineering testing in regards to future martin exploration missions. We propose that the variety of exogenic and endogenic geomorphic types, lacustrine sediments, evaporite mineral assemblages and Mars-like extreme environments collectively point to the Qaidam Basin as an optimal [ABSTRACT FROM AUTHOR]

Deltas are water-related sedimentary landforms commonly discovered on Mars and Earth. During the formation of a delta, the self-weight consolidation process reduces its porosity and thickness. Previous studies on the martian consolidation process either adopted the terrestrial consolidation rate or ignored this process altogether. However, the consolidation process may diverge on these two planets due to their different gravity regimes, which may further affect the delta morphology and lithification and the estimation of the delta formation timescale. In this study, we carry out a series of laboratory experiments to determine the basic parameters for modeling consolidation using water-saturated martian sediment simulants. The consolidation process is modeled with Gibson's 1-D consolidation model for deltas with different initial thicknesses (20–150 m) and different types of base drainage conditions (rigid bedrock and loose regolith). The modeling results suggest that for the delta area with fine grains, the settlement amount on Mars is lower than that on Earth, which indicates the martian delta to be looser, more erodible and more easily disturbed than the counterparts on Earth from the effects of the consolidation process alone. Higher delta channelization, more sediment deformations and post-deposition erosions before significant cementation are thus expected on Mars. More cementation/recrystallization is needed for martian deltas to be lithified. By using the simulated final porosity of martian deltas (0.45–0.46) and an updated timescale calculation formula, estimated delta formation timescale is reduced to be 32–44% of the previous results. • Basic parameters for the consolidation process are obtained by lab experiments. • The delta consolidation process on Mars is slower than that on Earth. • The timescale of a martian delta formation is 32%–44% of results in previous studies. • The consolidation process affected martian delta morphology and lithification. [ABSTRACT FROM AUTHOR]

This article introduces a new technology about a rod pumping in the offshore platform according to the demand of offshore heavy oil thermal recovery and the production of stripper well, analyzes the research status of hydraulic pumping unit at home and abroad, and designs a new kind of miniature hydraulic pumping unit with long-stroke, low pumping speed and compact structure to resolve the problem of space limitation. The article also describes the whole structure and the working principle of this pumping unit, determines the choice of stroke and rate of the pumping unit, and establishes mathematical models based on the polished rod loads. A new composite hydraulic cylinder with a special structure was designed by combining the hydraulic cylinder with the energy accumulator. This composite hydraulic cylinder is applied on land, and the model prototype runs smoothly, which indicates that the whole structure design of the pumping unit is reasonable and the control strategy is correct. [ABSTRACT FROM AUTHOR]

Chemical equations are presented for the article "Chiral Bifunctional Guanidine-Catalyzed Enantioselective Aza-Henry Reaction of Isatin-Derived Ketimines" by B. Fang & others published in a 2015 issue of the journal "Journal of Organic Chemistry."

An asymmetric synthesis of cyclic sulfamates by catalytic haloaminocyclization of primary sulfamate ester derivatives is described. The remarkable reversal of diastereoselectivity was found to be dependent on the halogen source and the chiral catalyst. By using privileged complexes of N, N′-dioxides with Sc(OTf)3 or Lu(OTf)3 as the catalyst, a variety of enantioenriched syn- and anti-cyclic sulfamates or related trans-aziridines could be obtained in 92-99 % ee and up to 97 % yield. [ABSTRACT FROM AUTHOR]

Mare Fecunditatis is a ~310,000 km2 flat basalt plain located in the low-latitude area of the Moon. Plenty of volcanic features (multiple episodes of mare basalts, sinuous rilles, lava tubes, pyroclastic deposits, domes, irregular mare patches (IMP), ring-moat dome structures (RMDS), floor-fractured craters), tectonic features (grabens and wrinkle ridges), impact-related features, and other features (swirls, pit craters) are identified in Mare Fecunditatis. An in-situ mission to Mare Fecunditatis is scientifically significant to better understand the lunar thermal histories and other questions. All previous in-situ and human missions (Apollo, Luna, Chang'E) were limited to small areas, and no traverse longer than 40 km has been made yet. With the development of technology, long-distance movement will be possible in the future on the lunar surface, providing opportunities to explore multiple sites at one mission with complete documentation of the regional geology. Eight high-value targets (pit crater, IMPs, RMDSs, young basalts, high-Al basalts, pyroclastic deposits, swirls, and fresh craters) were found in Mare Fecunditatis, and a ~1400 km-traverse in 5 years is proposed to explore them to solve the most fundamental lunar questions. [ABSTRACT FROM AUTHOR]

Computational chemistry, peptides, phosphines, redox chemistry, visible-light chemistry Keywords: computational chemistry; peptides; phosphines; redox chemistry; visible-light chemistry EN computational chemistry peptides phosphines redox chemistry visible-light chemistry 1 1 1 01/20/22 20220126 NES 220126 B Amides are ubiquitous b in biological and medicinal chemistry. Inside Back Cover: Generation of Oxyphosphonium Ions by Photoredox/Cobaloxime Catalysis for Scalable Amide and Peptide Synthesis in Batch and Continuous-Flow (Angew. [Extracted from the article]

Computational chemistry, peptides, phosphines, redox chemistry, visible-light chemistry Keywords: computational chemistry; peptides; phosphines; redox chemistry; visible-light chemistry EN computational chemistry peptides phosphines redox chemistry visible-light chemistry 1 1 1 01/20/22 20220126 NES 220126 B Amide b sind in der biologischen und medizinischen Chemie allgegenwärtig. Innenrücktitelbild: Generation of Oxyphosphonium Ions by Photoredox/Cobaloxime Catalysis for Scalable Amide and Peptide Synthesis in Batch and Continuous-Flow (Angew. [Extracted from the article]