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A large amount of transverse aeolian ridges (TARs) bedforms exist in the Zhurong rover landing region. The acquisition of high‐resolution data from the orbiter and the rover from Tianwen‐1 mission provides an excellent opportunity to study the geological characteristics of TARs. The length, width, and density of a total of 8,274 TAR samples at the landing site were analyzed. The orientation of TARs at the landing region is dominated in the E‐W direction. Analysis of Mars Climate Station (MCS) data on the Zhurong rover shows that the present‐day wind direction is inconsistent with the wind forces that promoted the formation of TARs, suggesting that the formation of TARs is dependent on the ancient wind direction. With the help of the Zhurong MarSCoDe shortwave infrared (SWIR) spectrometer data, we investigate the composition of materials including TARs, soil, and rocks, and the results show that their spectra display similar distinct absorptions consistent with the presence of hydrated minerals such as hydrated sulfates. The cemented and dusty crust covering the TARs indicates that the TARs have not migrated for a period of time in the landing site area. Some of the TARs have been eroded into small sand ridges or ripples due to the change in the prevailing wind directions, which may indicate the climate change on Mars. Plain Language Summary: Using the high‐resolution remote sensing images from the orbiter and Zhurong rover of Tianwen‐1 mission, we identified a total of 8,274 aeolian bedforms at the landing site of the rover on the Utopia Planitia. These aeolian bedforms can be classified as transverse aeolian ridges (TARs) according to their morphology, size and other observational features. The detailed geometry such as the length, the width, the density, and orientation of these TARs were characterized and compared with Martian TARs measured in the previous studies. The TARs in the study area were found to have formed in an ancient wind regime. The TARs are covered with bright dust and their surfaces have been cemented. This suggests that these TARs have not moved for a long time. Some of the TARs have been eroded into small sand ripples. The cause of this may be related to the change in the direction of the ancient wind because the current wind direction derived from the Mars Climate Station (MCS) data on the Zhurong rover is found to be different from the ancient wind direction. Key Points: The geomorphology of transverse aeolian ridges (TARs) at Zhurong landing area are mapped and analyzed and the results show that they formed at an ancient wind regimeThe cemented and dusty crust covering the TARs indicate that the TARs have not migrated for a period of timeSome of the TARs have been eroded due to the change of the prevailing wind directions which may indicate the climate change on Mars [ABSTRACT FROM AUTHOR]

While quantum computing provides an exponential advantage in solving the system of linear equations, there is little work to solve the system of nonlinear equations with quantum computing. We propose quantum Newton's method (QNM) for solving N -dimensional system of nonlinear equations based on Newton's method. In QNM, we solve the system of linear equations in each iteration of Newton's method with quantum linear system solver. We use a specific quantum data structure and l ∞ tomography with sample error ϵ s to implement the classical-quantum data conversion process between the two iterations of QNM, thereby constructing the whole process of QNM. The complexity of QNM in each iteration is O (log 4 N ∕ ϵ s 2). Through numerical simulation, we find that when ϵ s ≫ 1 ∕ N , QNM is still effective, so the complexity of QNM is sublinear with N , which provides quantum advantage compared with the optimal classical algorithm. [ABSTRACT FROM AUTHOR]

Infectious diseases threaten the health and survival of wildlife populations. Consequently, relationships between host diversity, host abundance, and parasite infection are important aspects of disease ecology and conservation research. Here, we report on the prevalence patterns of avian Plasmodium and Haemoproteus infections and host relative abundance influence based on sampling 728 wild-caught birds representing 124 species at seven geographically widespread sites in southern China. The overall prevalence of two haemoprotozoan parasites, Plasmodium and Haemoproteus, was 29.5%, with 22.0% attributable to Haemoproteus and 7.8% to Plasmodium. Haemoproteus prevalence differed significantly among different avian host families, with the highest prevalence in Nectariniidae, Pycnonotidae and Muscicapidae, whereas Plasmodium prevalence varied significantly among host species. Seventy-nine mitochondrial lineages including 25 from Plasmodium and 54 from Haemoproteus were identified, 80% of which were described here for the first time. The phylogenetic relationships among these parasites indicated stronger host-species specificity for Haemoproteus than Plasmodium. Well-supported host-family (Timaliidae) specific clades were found in both Plasmodium and Haemoproteus. The Haemoproteus tree shows regional subclades, whereas the Plasmodium clades are “scattered” among different geographical regions. Interestingly, there were statistically significant variations in the prevalence of Plasmodium and Haemoproteus among the geographical regions. Furthermore, the prevalence of Plasmodium and Haemoproteus were not significantly correlated with host relative abundance. Further efforts will focus on exploring the relationships between parasite prevalence and sex, age, and immune defense of the host. [ABSTRACT FROM AUTHOR]

The process of discovering species is a fundamental responsibility of systematics. Recently, there has been a growing interest in coalescent-based methods of species delimitation aimed at objectively identifying species early in the divergence process. However, few empirical studies have compared these new methods with character-based approaches for discovering species. In this study, we applied both a character-based and a coalescent-based approaches to delimit species in a closely related avian complex, the light-vented/Taiwan bulbul ( Pycnonotus sinensis/ Pycnonotus taivanus). Population aggregation analyses of plumage, mitochondrial and 13 nuclear intron character data sets produced conflicting species hypotheses with plumage data suggesting three species, mitochondrial data suggesting two species, and nuclear intron data suggesting one species. Such conflict is expected among recently diverged species, and by integrating all sources of data, we delimited three species verified with independently congruent character evidence as well as a more weakly supported fourth species identified by a single character. Attempts to validate species hypothesis using Bayesian Phylogenetics and Phylogeography ( BPP), a coalescent-based method of species delimitation, revealed several issues that can seemingly affect statistical support for species recognition. We found that θ priors had a dramatic impact on speciation probabilities, with lower values consistently favouring splitting and higher values consistently favouring lumping. More resolved guide trees also resulted in overall higher speciation probabilities. Finally, we found suggestive evidence that BPP is sensitive to the divergent effects of nonrandom mating caused by intraspecific processes such as isolation-with-distance, and therefore, BPP may not be a conservative method for delimiting independently evolving population lineages. Based on these concerns, we questioned the reliability of BPP results and based our conclusions about species limits exclusively on character data. [ABSTRACT FROM AUTHOR]

Abstract: Geographic variation in the Black-throated Laughingthrush (Garrulax chinensis) is examined to infer the influence of Pleistocene glacial oscillations on the genetic diversity of its subspecies. Mitochondrial evidence suggests that the endemic Hainan Island taxon, G. c. monachus, is monophyletic, whereas its closest continental relatives, G. c. chinensis and G. c. lochmius, are not. Multilocus coalescent analysis based on two mitochondrial and two nuclear intron loci indicates inter-subspecific genetic differentiation during the Pleistocene and substantial post-divergence genetic introgression from G. c. chinensis into G. c. lochmius. In contrast, G. c. monachus experienced no post-divergence gene flow despite occasional land-bridge contact with its continental relatives, suggesting its isolation may have been imposed by ecology as well as geography. It is probably reproductively isolated and should be treated as a distinct species. [Copyright &y& Elsevier]

The light-vented bulbul Pycnonotus sinensis is a small resident passerine that is found widely in central and south China, North Vietnam, and some East Asian islands, including Hainan, Taiwan and the Ryukyu Islands. Its subspecies status has been under considerable debate. A total of 10 subspecies have been proposed, but only 4 are widely recognized, including 1 continental taxon, P. s. sinensis, and 3 insular subspecies: P. s. hainanus, P. s. formosae and P. s. orii. Two mitochondrial DNA genes and 9 microsatellite loci were used to investigate the genetic divergence of this species, to identify the evolutionary status of 2 insular subspecies ( P. s. hainanus and P. s. formosae) and to uncover probable historical causes that shaped them. The results reveal that P. s. formosae has diverged significantly from the other 2 subspecies because of a substantial time of isolation for populations on Taiwan Island. There was no significant genetic differentiation between P. s. sinensis and P. s. hainanus. The notable morphological difference in P. s. hainanus might be attributed to a rapid, recent adaptation to the tropical environment of Hainan Island. The low genetic divergence between P. s. sinensis and P. s. hainanus might result from a recent divergence or gene flow between them. Two insular subspecies of light-vented bulbul populations might have diverged recently from their continental relatives through a complex evolution history owing to island isolation, ecological isolation, and possibly even hybridization. Both P. s. hainanus and P. s. formosae should be considered important conservation units because of their morphological and genetic distinctiveness. [ABSTRACT FROM AUTHOR]

Abstract: Entanglement witnesses (EW) are non-positive Hermitian operators which can detect the presence of entanglement. Let denote the set of entangled states detected by the entanglement witness W. In [M. Lewenstein, B. Kraus, J.I. Cirac, P. Horodecki, Phys. Rev. A 62 (2001) 052310], authors showed that if and only if there exists a positive operator P and such that . In this Letter, we consider the following problem that if there exists no inclusion relation between and , then how to determine whether their intersection is an empty set or not. We show that there exists a state ρ detected by and if and only if for any , is not a positive operator. And this result can be generalized to the finite number of EWs. [Copyright &y& Elsevier]

Traditional mechanical properties prediction models are mostly based on experience and mechanism, which neglect the linear and nonlinear relationships between process parameters. Aiming at the high-dimensional data collected in the complex industrial process of steel production, a new prediction model is proposed. The multidimensional support vector regression (MSVR)-based model is combined with the feature selection method, which involves maximum information coefficient (MIC) correlation characterization and complex network clustering. Firstly, MIC is used to measure the correlation between process parameters and mechanical properties, based on which a complex network is constructed and hierarchical clustering is performed. Secondly, we evaluate all parameters and select a representative one for each partition as the input of the subsequent model based on the centrality and influence indicators. Finally, an actual steel production case is used to train the MSVR prediction model. The prediction results show that our proposed framework can capture effective features from the full parameters in terms of higher prediction accuracy and is less time-consuming compared with the Pearson-based subset, full-parameter subset, and empirical subset input. The feature selection method based on MIC can dig out some nonlinear relationships which cannot be found by Pearson coefficient. [ABSTRACT FROM AUTHOR]

The location and grade setting of a timber logistics center is an important link in the optimization of the timber logistics system, the rationality of which can effectively improve the efficiency of the timber logistics supply chain. There is a long distance between the main forested areas in China, and more than 55% of the timber demand depends on imports. Research and practice of systematically planning timber logistics centers in the whole country have not been well carried out, which reduces the efficiency of timber logistics. In this paper, 47 timber trading markets with a certain scale in China are selected as the basis for logistics center selection. Based on their transportation network relationship and the number of enterprises in the market, combined with the complex network theory and data analysis method, the network characteristics of three different transportation networks are measured. After determining the transportation capacity indicator, the logistics capacity coefficient is measured based on the freight volume of each node. Then, the important nodes are identified, and each node is graded to systematically set up the timber logistics center. [ABSTRACT FROM AUTHOR]

Objective: To quantitatively measure the anatomical variations of the pelvic floor in children with exstrophy-epispadias complex using magnetic resonance imaging.Materials and Methods: Six cases of classic bladder exstrophy (CBE), 5 cases of penile epispadias (PE) and 11 cases of penopubic epispadias (PPE) were included. Another 8 cases with the testicular tumor were taken as the controls. A series of measurements obtained from the pelvic floor magnetic resonance imaging were analyzed, and the measurements with significant differences were obtained by ANOVA.Results: The pelvic floor of the CBE was significantly different from that of controls in measurements including wider pubic diastasis (P <.001), greater posterior anal distance (P = .019), greater posterior bladder neck distance (P = .004), larger iliac wing angle (P <.001), diminutive ischial angle (P <.001), bigger puborectalis angle (P <.001), larger ileococcygeous angle (P = .002) and shortened anterior corporal length (P <.001). For the PE, the posterior bladder neck distance (P = .038) was greater than that of controls. In the PPE, the posterior bladder neck distance (P = .001) and puborectalis angle (P = .026) was greater than that of controls, respectively.Conclusion: CBE shows severe anatomical variations of the pelvic floor. The bladder neck moves more anteriorly both in PE and PPE than the control. The enlarged puborectalis angle resulting from wider pubic diastasis and more anterior position of the anorectal canal is also noticed in PPE. [ABSTRACT FROM AUTHOR]

• Inverted sinuous ridges and candidate floodplain clays were found to the east of Tempe Terra on Mars. • The inverted ridges may represent exhumation of the channel belts and overbank deposits. • The findings imply prolonged fluvial activity on early Mars, potentially for tens of thousands of years. The climate on early Mars is one of the major unsolved problems in planetary science. It is unclear whether early Mars was warm and wet or cold and icy. Morphological features on Mars such as sinuous ridges could provide critical constraints to address this issue. Here we investigate several sinuous ridges to the east of Tempe Terra, located at the dichotomy boundary of the highland terrain and lowland plains and find these ridges may have recorded persistent fluvial activity on early Mars. Our analysis indicates that these ridges may represent exhumation of the channel belts and overbank deposits formed from meandering rivers over significant geologic time. Layered smectite-bearing minerals are distributed along the flank of the ridges, and could be detrital or authigenic floodplain clays. Our interpretation of the stratigraphic relationships indicates that the layered smectite-bearing materials lie between channel belt deposits, which has rarely been previously reported on Mars and supports the floodplain interpretation. Our results suggest a persistent warm period, perhaps triggered by volcanism, impacts, and/or variations in planetary obliquity, that persisted for a geologically significant interval (tens of thousands of years) during the Noachian period of Mars. [ABSTRACT FROM AUTHOR]

Chromatin replication is intricately intertwined with the recycling of parental histones to the newly duplicated DNA strands for faithful genetic and epigenetic inheritance. The transfer of parental histones occurs through two distinct pathways: leading strand deposition, mediated by the DNA polymerase ε subunits Dpb3/Dpb4, and lagging strand deposition, facilitated by the MCM helicase subunit Mcm2. However, the mechanism of the facilitation of Mcm2 transferring parental histones to the lagging strand while moving along the leading strand remains unclear. Here, we show that the deletion of Pol32, a nonessential subunit of major lagging-strand DNA polymerase δ, results in a predominant transfer of parental histone H3-H4 to the leading strand during replication. Biochemical analyses further demonstrate that Pol32 can bind histone H3-H4 both in vivo and in vitro. The interaction of Pol32 with parental histone H3-H4 is disrupted through the mutation of the histone H3-H4 binding domain within Mcm2. Our findings identify the DNA polymerase δ subunit Pol32 as a critical histone chaperone downstream of Mcm2, mediating the transfer of parental histones to the lagging strand during DNA replication., Competing Interests: Competing interests statement:The authors declare no competing interest.

The Mars' climate is cold and dry in the most recent epoch, and liquid water activities are considered extremely limited. Previous orbital data only show sporadic hydrous minerals in the northern lowlands of Mars excavated by large impacts. Using the short-wave infrared spectral data obtained by the Zhurong rover of China's Tianwen-1 mission, which landed in southern Utopia Planitia on Mars, we identify hydrated sulfate/silica materials on the Amazonian terrain at the landing site. These hydrated minerals are associated with bright-toned rocks, interpreted to be duricrust developed locally. The lithified duricrusts suggest that formation with substantial liquid water originates by either groundwater rising or subsurface ice melting. In situ evidence for aqueous activities identified at Zhurong's landing site indicates a more active Amazonian hydrosphere for Mars than previously thought.

Background: To retrospectively analyze the pulmonary computed tomography (CT) characteristics and dynamic changes in the lungs of cured coronavirus disease 2019 (COVID-19) patients at discharge and reexamination., Methods: A total of 155 cured COVID-19 patients admitted to designated hospitals in Yunnan Province, China, from February 1, 2020, to March 20, 2020, were included. All patients underwent pulmonary CT at discharge and at 2 weeks after discharge (during reexamination at hospital). A retrospective analysis was performed using these two pulmonary CT scans of the cured patients to observe changes in the number, distribution, morphology, and density of lesions., Results: At discharge, the lung CT images of 15 cured patients showed no obvious lesions, while those of the remaining 140 patients showed different degrees of residual lesions. Patients with moderate disease mostly had multiple pulmonary lesions, mainly in the lower lobes of both lungs. At reexamination, the lung lesions in the patients with moderate disease had significantly improved (P<0.05), and the lung lesions in the patients with severe disease had partially improved, especially in patients with multi-lobe involvement (χ 2 =3.956, P<0.05). At reexamination, the lung lesions of patients with severe disease did not show significant changes (P>0.05)., Conclusions: The pulmonary CT manifestations of cured COVID-19 patients had certain characteristics and variation patterns, providing a reference for the clinical evaluation of treatment efficacy and prognosis of patients.