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For direction-of-arrival (DOA) estimation problems in a sparse domain, sparse Bayesian learning (SBL) is highly favored by researchers owing to its excellent estimation performance. However, traditional SBL-based methods always assign Gaussian priors to parameters to be solved, leading to moderate sparse signal recovery (SSR) effects. The reason is Gaussian priors play a similar role to l 2 regularization in sparsity constraint. Therefore, numerous methods are developed by adopting hierarchical priors that are used to perform better than Gaussian priors. However, these methods are in straitened circumstances when multiple measurement vector (MMV) data are adopted. On this basis, a block-sparse SBL method (named BSBL) is developed to handle DOA estimation problems in MMV models. The novelty of BSBL is the combination of hierarchical priors and block-sparse model originating from MMV data. Therefore, on the one hand, BSBL transfers the MMV model to a block-sparse model by vectorization so that Bayesian learning is directly performed, regardless of the prior independent assumption of different measurement vectors and the inconvenience caused by the solution of matrix form. On the other hand, BSBL inherited the advantage of hierarchical priors for better SSR ability. Despite the benefit, BSBL still has the disadvantage of relatively large computation complexity caused by high dimensional matrix operations. In view of this, two operations are implemented for low complexity. One is reducing the matrix dimension of BSBL by approximation, generating a method named BSBL-APPR, and the other is embedding the generalized approximate message passing (GAMB) technique into BSBL so as to decompose matrix operations into vector or scale operations, named BSBL-GAMP. Moreover, BSBL is able to suppress temporal correlation and handle wideband sources easily. Extensive simulation results are presented to prove the superiority of BSBL over other state-of-the-art algorithms. [ABSTRACT FROM AUTHOR]

The research aims to study the application of remote Femto Second (FS) technology in black silicon material preparation and optical devices. Based on the principle and characteristic research of FS technology, the interaction between FS and silicon is adopted to propose a scheme for preparing black silicon material through experiments. Moreover, the experimental parameters are optimized. Then, the scheme of using the FS for etching polymer optical power splitter as a new technical means is proposed. In addition, while ensuring processing accuracy, the appropriate process parameters of laser etching photoresist are obtained. The results show that the performance of black silicon prepared with SF6 as the background gas is greatly improved in the 400-2200nm range. However, the performance of black silicon samples with the two-layer structure etched at different laser energy densities has little difference. Black silicon with a Se+Si two-layer film structure has the best optical absorption performance in the infrared range of 1100nm-2200nm. Besides, the optical absorption rate is the highest when the laser scanning rate is 0.5mm/s. In the band of >1100nm, when the maximum laser energy density is 6.5kJ/m2, the overall absorption of the etched sample is the worst. The absorption rate is the best when the laser energy density is 3.9kJ/m2. It suggests that the proper parameter selection greatly impacts the quality of the final laser-etched sample. [ABSTRACT FROM AUTHOR]

Phytophthora root rot is a destructive soybean disease worldwide, which is caused by the oomycete pathogen Phytophthora sojae (P. sojae). Wall-associated protein kinase (WAK) genes, a family of the receptor-like protein kinase (RLK) genes, play important roles in the plant signaling pathways that regulate stress responses and pathogen resistance. In our study, we found a putative Glycine max wall-associated protein kinase, GmWAK1, which we identified by soybean GmLHP1 RNA-sequencing. The expression of GmWAK1 was significantly increased by P. sojae and salicylic acid (SA). Overexpression of GmWAK1 in soybean significantly improved resistance to P. sojae, and the levels of phenylalanine ammonia-lyase (PAL), SA, and SA-biosynthesis-related genes were markedly higher than in the wild-type (WT) soybean. The activities of enzymatic superoxide dismutase (SOD) and peroxidase (POD) antioxidants in GmWAK1-overexpressing (OE) plants were significantly higher than those in in WT plants treated with P. sojae; reactive oxygen species (ROS) and hydrogen peroxide (H2O2) accumulation was considerably lower in GmWAK1-OE after P. sojae infection. GmWAK1 interacted with annexin-like protein RJ, GmANNRJ4, which improved resistance to P. sojae and increased intracellular free-calcium accumulation. In GmANNRJ4-OE transgenic soybean, the calmodulin-dependent kinase gene GmMPK6 and several pathogenesis-related (PR) genes were constitutively activated. Collectively, these results indicated that GmWAK1 interacts with GmANNRJ4, and GmWAK1 plays a positive role in soybean resistance to P. sojae via a process that might be dependent on SA and involved in alleviating damage caused by oxidative stress. [ABSTRACT FROM AUTHOR]

• A DOA estimation method based on variational Bayesian inference is proposed. • The minimum hole array is adopted to maximize the array aperture based sparse representation. • A sparsity-inducing Bayesian framework with three-stage hierarchical Laplace priors is developed. • The unknown noise is eliminated by a selection matrix. • A refinement operation based on Newton's method is developed to compensate the off-grid errors. For direction-of-arrival (DOA) estimation problems, sparse Bayesian learning (SBL) has achieved excellent estimation performance, especially in sparse arrays. However, numerous SBL-based methods with hyperparameters assigned to Gaussian priors cannot enhance sparsity well, and mainly focus on the nested array (NA) or the co-prime array (CPA) that cause relatively large degree of freedom (DOF) losses. Based on this, we propose a novel method with a Bayesian framework containing three-stage hierarchical Laplace priors that significantly promote sparsity. Moreover, the proposed method is based on the minimum hole array (MHA) that retains a larger array aperture than NA or CPA after redundancy removal, which is required and achieved simultaneously by a denoising operation. In addition, to correct the intractable off-grid model errors caused by grid mismatch, a new refinement operation is developed. And, the refinement empirically outperforms others based on Taylor expansion. Extensive simulations are presented to confirm the superiority of the proposed method beyond state-of-the-art methods. [ABSTRACT FROM AUTHOR]

• Surface topography evolves from the bump to the crater as laser fluence rises. • Mass inflow caused by solid-phase oxidation of material produces "flat-topped" bumps. • Oxygen mass inflow and surface oxygen content greatly influence "M-shaped" bumps. • Surface tension considering oxygen content forms outward flows and crater topography. • Pulse width greatly influences three types of surface morphologies through heat and mass transfer as well as fluid flow. The evolution of surface topography of 304L stainless steel, induced by a fiber laser with a wavelength of 1070 nm and a pulse width of 10 μs in ambient air, is studied experimentally in the fluence range between roughly 30 J/cm2 and 118 J/cm2. A two-dimensional (2D) transient model is developed to simulate the laser micromachining process of 304L stainless steel, which incorporates the heat and mass transfer as well as fluid flow. An oxidation kinetics model is established to describe the mass inflow caused by high temperature oxidation of stainless steel in both solid and liquid phases, and the oxygen concentration on the surface of the molten liquid is treated as a function of temperature and then applied to the expression of surface tension coefficient. A modified level-set method is developed to trace the free surface and consider the mass transfer caused by oxidation and evaporation, and the possible effects on the free surface boundary containing surface tension, recoil pressure, Marangoni effect and the shear stress caused by metallic vapor flow are coupled in the model. Based on this model, the impacts of laser fluence, ambient air and pulse duration on both laser micromachining processes and the evolution of surface topography from the bump to the crater are numerically investigated. Comparing the experimental results and the numerical results, the validity of the model is verified, and the formation mechanisms of both various topographies and phenomena during laser micromachining are analyzed. The results show that with the increase of laser fluence the irradiated zone presents the "flat-topped" bump, the "M-shaped" bump and the "Gaussian-like" crater successively. Furthermore, the mass inflow has a great influence on the topography of both the "flat-topped" bump and the "M-shaped" bump. Even though the surface tension considering oxygen concentration plays an important role in the formation of both the "M-shaped" bump and the "Gaussian-like" crater, evaporation largely determines the surface topography of the "Gaussian-like" crater at high laser fluences. [ABSTRACT FROM AUTHOR]

The evolution of surface topography of 304L stainless steel, induced by long pulse laser with a wavelength of 1070 nm and a pulse width of 10 μs and a pulse number of 400 in air, was investigated in the fluence range between around 3 J/cm2 and 210 J/cm2. Three-dimensional (3D) morphologies and two-dimensional (2D) cross-sectional profiles of microstructures at different laser fluences were compared. Furthermore, surface profiles of the microstructures were quantified by using the inner diameter, the outer diameter, the elevation of central area and the rim height thereof. The trends of the above four geometrical parameters and surface profiles suggest five laser fluence ranges, where the corresponding topographies change from bump to crater. Energy dispersive spectrometer (EDS) was used to analyze surface elements of different microstructures, and the results showed that the content of oxygen had a great influence on surface tension and surface topography. In this study, a complex picture was drawn where melting, vaporization, solidification, melt displacement, melt expulsion and plasma shielding take place at different laser fluences. [ABSTRACT FROM AUTHOR]

This paper proposes a dynamic infectious disease model for COVID-19 daily counts data and estimate the model using the Langevinized EnKF algorithm, which is scalable for large-scale spatio-temporal data, converges to the right filtering distribution, and is thus suitable for performing statistical inference and quantifying uncertainty for the underlying dynamic system. Under the framework of the proposed dynamic infectious disease model, we tested the impact of temperature, precipitation, state emergency order and stay home order on the spread of COVID-19 based on the United States county-wise daily counts data. Our numerical results show that warm and humid weather can significantly slow the spread of COVID-19, and the state emergency and stay home orders also help to slow it. This finding provides guidance and support to future policies or acts for mitigating the community transmission and lowering the mortality rate of COVID-19. [ABSTRACT FROM AUTHOR]

Objective: The goal of this study was to examine the relation between users' reported risk concerns and their choice behaviors in a mobile application (app) selection task. Background: Human users are typically regarded as the weakest link in cybersecurity and privacy protection; however, it is possible to leverage the users' predilections to increase security. There have been mixed results on the relation between users' self-reported privacy concerns and their behaviors. Method: In three experiments, the timing of self-reported risk concerns was either a few weeks before the app-selection task (pre-screen), immediately before it (pre-task), or immediately after it (post-task). We also varied the availability and placement of clear definitions and quizzes to ensure users' understanding of the risk categories. Results: The post-task report significantly predicted the app-selection behaviors, consistent with prior findings. The pre-screen report was largely inconsistent with the reports implemented around the time of the task, indicating that participants' risk concerns may not be stable over time and across contexts. Moreover, the pre-task report strongly predicted the app-selection behaviors only when elaborated definitions and quizzes were placed before the pre-task question, indicating the importance of clear understanding of the risk categories. Conclusion: Self-reported risk concerns may be unstable over time and across contexts. When explained with clear definitions, self-reported risk concerns obtained immediately before or after the app-selection task significantly predicted app-selection behaviors. Application: We discuss implications for including personalized risk concerns during app selection that enable comparison of alternative mobile apps. [ABSTRACT FROM AUTHOR]

Trust management is an approach to scalable and flexible access control in decentralized systems. In trust management, a server often needs to evaluate a chain of credentials submitted by a client; this requires the server to perform multiple expensive digital signature verifications. In this paper, we study low-bandwidth Denial-of-Service (DoS) attacks that exploit the existence of trust management systems to deplete server resources. Although the threat of DoS attacks has been studied for some application-level protocols such as authentication protocols, we show that it is especially destructive for trust management systems. Exploiting the delegation feature in trust management languages, an attacker can forge a long credential chain to force a server to consume a large amount of computing resource. Using game theory as an analytic tool, we demonstrate that unprotected trust management servers will easily fall prey to a witty attacker who moves smartly. We report our empirical study of existing trust management systems, which manifests the gravity of this threat. We also propose a defense technique using credential caching, and show that it is effective in the presence of intelligent attackers. [ABSTRACT FROM AUTHOR]

Fengyun-3C (FY-3C) is a second-generation meteorological satellite of China that was launched on 23 September 2013. The on board Visible and Infrared Radiometer (VIRR) can be used to observe global sea surface temperature (SST). In this paper, the VIRR SST products are compared with MODIS SST products and buoy measurements from 2015 to 2019. The collocations of VIRR, MODIS, and buoy SST are generated separately during the day and night with the spatial window of 0.05° × 0.05°. The comparison results show that the biases of VIRR SST minus buoy SST during the day and night are −0.21 and −0.13 °C with a corresponding robust standard deviation (RSD) of 0.58 and 0.59 °C, respectively. The mean differences between VIRR and MODIS are −0.10 and 0.08 °C with RSDs of 0.53 and 0.58 °C for the daytime and nighttime, respectively. The consistency of VIRR SST accuracy from 2015 to 2019 and the dependence of VIRR SST error on SST and latitude are also investigated. [ABSTRACT FROM AUTHOR]

Abstract: When releasing microdata for research purposes, one needs to preserve the privacy of respondents while maximizing data utility. An approach that has been studied extensively in recent years is to use anonymization techniques such as generalization and suppression to ensure that the released data table satisfies the k-anonymity property. A major thread of research in this area aims at developing more flexible generalization schemes and more efficient searching algorithms to find better anonymizations (i.e., those that have less information loss). This paper presents three new generalization schemes that are more flexible than existing schemes. This flexibility can lead to better anonymizations. We present a taxonomy of generalization schemes and discuss their relationship. We present enumeration algorithms and pruning techniques for finding optimal generalizations in the new schemes. Through experiments on real census data, we show that more-flexible generalization schemes produce higher-quality anonymizations and the bottom-up works better for small k values and small number of quasi-identifier attributes than the top-down approach. [Copyright &y& Elsevier]

SPKI/SDSI is a language for expressing distributed access control policy, derived from SPKI and SDSI. We provide a first-order logic (FOL) semantics for SDSI, and show that it has several advantages over previous semantics. For example, the FOL semantics is easily extended to additional policy concepts and gives meaning to a larger class of access control and other policy analysis queries. We prove that the FOL semantics is equivalent to the string rewriting semantics used by SDSI designers, for all queries associated with the rewriting semantics. We also provide a FOL semantics for SPKI/SDSI and use it to analyze the design of SPKI/SDSI. This reveals some problems. For example, the standard proof procedure in RFC 2693 is semantically incomplete. In addition, as noted before by other authors, authorization tags in SPKI/SDSI are algorithmically problematic, making a complete proof procedure unlikely. We compare SPKI/SDSI with RT1C, which is a language in the RT Role-based Trust-management framework that can be viewed as an extension of SDSI. The constraint feature of RT1C, based on Constraint Datalog, provides an alternative mechanism that is expressively similar to SPKI/SDSI tags, semantically natural, and algorithmically tractable. [ABSTRACT FROM AUTHOR]

We propose a new cryptographic primitive called oblivious signature-based envelope (OSBE). Informally, an OSBE scheme enables a sender to send an envelope (encrypted message) to a receiver, and has the following two properties: (1) The receiver can open the envelope if and only if it has a third party’s (e.g., a certification authority’s) signature on an agreed-upon message. (2) The sender does not learn whether the receiver has the signature or not. We show that OSBE can be used to break policy cycles in automated trust negotiation (ATN) and to achieve oblivious access control. We develop a provably secure and efficient OSBE protocol for certificates signed using RSA signatures, as well as provably secure and efficient one-round OSBE protocols for Rabin and BLS signatures from recent constructions for identity-based encryption. We also present constructions for Generalized OSBE, where signatures on multiple messages (and possibly by different authorities) are required to open the envelope. [ABSTRACT FROM AUTHOR]

We introduce a simple Role-based Trust-management language RTOur goal-directed, distributed chain discovery algorithm finds and retrieves credentials as needed. We prove that the algorithm is correct by proving that the algorithm is sound and complete with respect to the credential graph composed of the credentials it retrieves, and that the algorithm retrieves all credentials that constitute a traversable chain. We further introduce a storage type system for RT [ABSTRACT FROM AUTHOR]

Federation is a popular concept in building distributed cyberinfrastructures, whereby computational resources are provided by multiple organizations through a unified portal, decreasing the complexity of moving data back and forth among multiple organizations. Federation has been used in bioinformatics only to a limited extent, namely, federation of datastores, e.g. SBGrid Consortium for structural biology and Gene Expression Omnibus (GEO) for functional genomics. Here, we posit that it is important to federate both computational resources (CPU, GPU, FPGA, etc.) and datastores to support popular bioinformatics portals, with fast-increasing data volumes and increasing processing requirements. A prime example, and one that we discuss here, is in genomics and metagenomics. It is critical that the processing of the data be done without having to transport the data across large network distances. We exemplify our design and development through our experience with metagenomics-RAST (MG-RAST), the most popular metagenomics analysis pipeline. Currently, it is hosted completely at Argonne National Laboratory. However, through a recently started collaborative National Institutes of Health project, we are taking steps toward federating this infrastructure. Being a widely used resource, we have to move toward federation without disrupting 50 K annual users. In this article, we describe the computational tools that will be useful for federating a bioinformatics infrastructure and the open research challenges that we see in federating such infrastructures. It is hoped that our manuscript can serve to spur greater federation of bioinformatics infrastructures by showing the steps involved, and thus, allow them to scale to support larger user bases. [ABSTRACT FROM AUTHOR]

Land use transitions are an important research area in land system science. In seeking a feasible way to improve rural residents' livelihoods and rural development, this paper explores the mechanism and effects of farmland use transition on rural livelihood transformation from the perspective of the human-land relationship. The theoretical framework of rural livelihood transformation as affected by farmland use transition is established, and econometric models are used to test the effects based on empirical panel data from China for the period 2000–2017. The major conclusions are drawn as follows. In essence, farmland use transition is the redistribution of agricultural productivity on farmland, and rural livelihood transformation is a process of long-term and trend transformation of rural residents' livelihood capital, livelihood structure, and livelihood pattern. Land use transitions boost the transformation of rural livelihood by regulating the rural human-land interactive relationship and substitutional relationship of elements in agricultural development. For every 1% increase in farmland management scale transition and farmland efficiency transition, rural livelihood transformation can be improved by 3.748% and 3.854%, respectively. The direction and intensity of the impact of farmland use transition on rural livelihood transformation differ by area and topographic conditions. Furthermore, people's livelihood finances and farmers' planting decisions regulate the effects of farmland use transition on rural livelihood transformation. The authors argue that regulating land use transitions can be an important component of policy-making to promote rural livelihoods transformation, and rural development transformation. • Theoretical framework for rural livelihood transformation affected by farmland use transition is established. • For every 1% increase in farmland scale and efficiency transition, rural livelihood transformation can be improved by 3.748% and 3.854%, respectively. • Impact of farmland use transition on rural livelihood transformation is heterogeneous in different areas and terrains. • People's livelihood finances and farmers' planting decisions will regulate the effect of farmland use transition on rural livelihoods transformation. • Regulating land use transition can be an important component of policy-making to promote rural livelihood transformation. [ABSTRACT FROM AUTHOR]

Recent findings suggest that cold acclimation can enhance cold resistance in wheat. Dongnongdongmai 1 (DM1) is a winter wheat variety that can overwinter at −30 °C; however, its cold acclimation mechanism is yet to be fully elucidated. Here, we elucidated the potential mechanisms of cold acclimation in DM1 and the China Spring (CS) variety, especially the role of the antioxidant system, using transcriptome and physiological analyses. Cold stress increased H2O2 and O2− production in both varieties; however, CS had higher contents of H2O2 and O2− than DM1. Moreover, cold significantly increased ROS-scavenging activities in DM1, especially at 30 days after exposure. Gene ontology (GO) analysis showed that differentially expressed peroxidase (POD) genes were enriched in antioxidant activity, with most POD genes being significantly upregulated in DM1 under cold acclimation. Additionally, cold acclimation increased the expression of cold acclimation protein (CAP), late embryogenesis abundant protein (LEA), and cold-responsive genes in both varieties, with higher expression levels in DM1. Overall, the results showed that DM1 exhibited a higher cold tolerance than CS during cold acclimation by increasing the expression of POD genes, LEA, CAP, and cold-responsive proteins, improving the understanding of the mechanism of cold resistance in DM1. [ABSTRACT FROM AUTHOR]

Several anonymization techniques, such as generalization and bucketization, have been designed for privacy preserving microdata publishing. Recent work has shown that generalization loses considerable amount of information, especially for high-dimensional data. Bucketization, on the other hand, does not prevent membership disclosure and does not apply for data that do not have a clear separation between quasi-identifying attributes and sensitive attributes. In this paper, we present a novel technique called slicing, which partitions the data both horizontally and vertically. We show that slicing preserves better data utility than generalization and can be used for membership disclosure protection. Another important advantage of slicing is that it can handle high-dimensional data. We show how slicing can be used for attribute disclosure protection and develop an efficient algorithm for computing the sliced data that obey the \ell-diversity requirement. Our workload experiments confirm that slicing preserves better utility than generalization and is more effective than bucketization in workloads involving the sensitive attribute. Our experiments also demonstrate that slicing can be used to prevent membership disclosure. [ABSTRACT FROM AUTHOR]

The threat of a cryptographically relevant quantum computer contributes to an increasing interest in the field of post-quantum cryptography (PQC). Compared to existing research efforts regarding the integration of PQC into the Transport Layer Security (TLS) protocol, industrial communication protocols have so far been neglected. Since industrial cyber-physical systems (CPS) are typically deployed for decades, protection against such long-term threats is needed. In this work, we propose two novel solutions for the integration of post-quantum (PQ) primitives (digital signatures and key establishment) into the industrial protocol Open Platform Communications Unified Architecture (OPC UA): a hybrid solution combining conventional cryptography with PQC and a solution solely based on PQC. Both approaches provide mutual authentication between client and server and are realized with certificates fully compliant to the X.509 standard. We implement the two solutions and measure and evaluate their performance across three different security levels. All selected algorithms (Kyber, Dilithium, and Falcon) are candidates for standardization by the National Institute of Standards and Technology (NIST). We show that Falcon is a suitable option – especially – when using floating-point hardware provided by our ARM-based evaluation platform. Our proposed hybrid solution provides PQ security for early adopters but comes with additional performance and communication requirements. Our solution solely based on PQC shows superior performance across all evaluated security levels in terms of handshake duration compared to conventional OPC UA but comes at the cost of increased handshake sizes. In addition to our performance evaluation, we provide a proof of security in the symbolic model for our two PQC-based variants of OPC UA. For this proof, we use the cryptographic protocol verifier ProVerif and formally verify confidentiality and authentication properties of our quantum-resistant variants. [ABSTRACT FROM AUTHOR]

Nowadays, online services, like e-commerce or streaming services, provide a personalized user experience through recommender systems. Recommender systems are built upon a vast amount of data about users/items acquired by the services. Such knowledge represents an invaluable resource. However, commonly, part of this knowledge is public and can be easily accessed via the Internet. Unfortunately, that same knowledge can be leveraged by competitors or malicious users. The literature offers a large number of works concerning attacks on recommender systems, but most of them assume that the attacker can easily access the full rating matrix. In practice, this is never the case. The only way to access the rating matrix is by gathering the ratings (e.g., reviews) by crawling the service's website. Crawling a website has a cost in terms of time and resources. What is more, the targeted website can employ defensive measures to detect automatic scraping. In this paper, we assess the impact of a series of attacks on recommender systems. Our analysis aims to set up the most realistic scenarios considering both the possibilities and the potential attacker's limitations. In particular, we assess the impact of different crawling approaches when attacking a recommendation service. From the collected information, we mount various profile injection attacks. We measure the value of the collected knowledge through the identification of the most similar user/item. Our empirical results show that while crawling can indeed bring knowledge to the attacker (up to 65% of neighborhood reconstruction on a mid-size dataset and up to 90% on a small-size dataset), this will not be enough to mount a successful shilling attack in practice. [ABSTRACT FROM AUTHOR]

Tamarin is a popular tool dedicated to the formal analysis of security protocols. One major strength of the tool is that it offers an interactive mode, allowing to go beyond what push-button tools can typically handle. Tamarin is for example able to verify complex protocols such as TLS, 5G, or RFID protocols. However, one of its drawback is its lack of automation. For many simple protocols, the user often needs to help Tamarin by writing specific lemmas, called "sources lemmas", which requires some knowledge of the internal behaviour of the tool. In this paper, we propose a technique to automatically generate sources lemmas in Tamarin. Following the intuition of manually written sources lemmas, our lemmas try to keep track of the origin of a term by looking into emitted messages or facts. We prove formally that our lemmas indeed hold, for arbitrary protocols that make use of cryptographic primitives that can be modelled with a subterm convergent equational theory (modulo associativity and commutativity). We have implemented our approach within Tamarin. Our experiments show that, in most examples of the literature, we are now able to generate suitable sources lemmas automatically, in replacement of the hand-written lemmas. As a direct application, many simple protocols can now be analysed fully automatically, while they previously required user interaction. [ABSTRACT FROM AUTHOR]

• The shoot apex differentiation of cold resistant wheat is slow. • MADS-box associated with differentiation of shoot apex in wheat at seedling stage. • Expression of cold-resistance genes in DM1 higher than in CS without low temperature. The shoot apex is a region where new cells are produced and elongate. The developmental state of the wheat shoot apex under low temperature affects its cold resistance. In this study, the morphology of shoot apex before overwintering was characterized for 24 wheat line with different winter and spring characteristics. Our research showed that the shoot apex of autumn-sown spring wheat lines reached the temperature sensitive double-ridge stage before overwintering, whereas shoot apex of winter wheat lines are found in temperature-insensitive vegetative or elongation stages. In order to explore how gene expression is associated with shoot apex differentiation in winter and spring wheat, we used strand-specific RNA sequencing to profile the gene expression patterns at four time-points between 14 after germination and 45 days after germination in the winter wheat cultivar Dongnongdongmai No. 1 (DM1) and in the spring wheat cultivar China Spring (CS). We identified 11,848 differentially expressed genes between the two cultivars. Most up-regulated genes in CS were involved in energy metabolism and transport during the seedling stage, whereas up-regulated genes in DM1 were involved in protein and DNA synthesis. MADS-box genes affect plant growth and development. In this study, MADS-boxes with differential expression between CS and DM1 were screened and evolutionary tree analysis was conducted. During all sampling periods, CS highly expressed MADS-box genes that induce flowering promotion genes such as VRN1 , VRT and AG, while lowly expressed MADS-box genes that induce flowering-inhibiting homologous genes such as SVP. TaVRN1 composition in DM1 and CS was vrn-A1 , vrn-B1 , and Vrn-D1b. Analysis of the sequence of TaVRN1 (TraesCS5A01G391700) from DM1 and CS revealed 5 SNP differences in the promoter regions and 3 SNP deletions in the intron regions. The expression levels of cold resistant genes in DM1 were significantly higher than those in CS at seedling stage (neither DM1 nor CS experienced cold in this study), including CBF, cold induced protein,acid desaturase and proline rich proteins. Additionally, the expression levels of auxin-related genes were significantly higher in CS than those in DM1 at 45 days after germination. Our study identified candidate genes associated with the process of differentiation of the shoot apex in winter and spring wheat at the seedling stage and also raised an internal stress tolerance model for winter wheat to endogenously anticipate the coming stressful conditions in winter. [ABSTRACT FROM AUTHOR]

Abstract: This paper analyzes the potential impacts of the Doha trade proposals (those of the USA, EU and G20) on agricultural production and incomes of China''s farmers by region and income group. By linking a global trade model to a national policy model which itself is connected to a set of disaggregated household data, we are able to assess the effects of the proposed Doha trade liberalizations on households both at the national and regional levels. According to the results of the model, the impacts of a Doha Round agreement on households differ significantly from those of China''s WTO accession. China''s economy would benefit from the trade liberalization associated with the Doha Round. The overall impacts, however, are relatively minor. Although farmers will benefit at the national level, the gains among farmers vary largely by income group and province. Also, the impacts on households that produce different types of crops differ. [Copyright &y& Elsevier]

Objective: Evaluate the effectiveness of training embedded within security warnings to identify phishing webpages.Background: More than 20 million malware and phishing warnings are shown to users of Google Safe Browsing every week. Substantial click-through rate is still evident, and a common issue reported is that users lack understanding of the warnings. Nevertheless, each warning provides an opportunity to train users about phishing and how to avoid phishing attacks.Method: To test use of phishing-warning instances as opportunities to train users' phishing webpage detection skills, we conducted an online experiment contrasting the effectiveness of the current Chrome phishing warning with two training-embedded warning interfaces. The experiment consisted of three phases. In Phase 1, participants made login decisions on 10 webpages with the aid of warning. After a distracting task, participants made legitimacy judgments for 10 different login webpages without warnings in Phase 2. To test the long-term effect of the training, participants were invited back a week later to participate in Phase 3, which was conducted similarly as Phase 2.Results: Participants differentiated legitimate and fraudulent webpages better than chance. Performance was similar for all interfaces in Phase 1 for which the warning aid was present. However, training-embedded interfaces provided better protection than the Chrome phishing warning on both subsequent phases.Conclusion: Embedded training is a complementary strategy to compensate for lack of phishing webpage detection skill when phishing warning is absent.Application: Potential applications include development of training-embedded warnings to enable security training at scale. [ABSTRACT FROM AUTHOR]

How the human user trusts and interacts with an automation system is influenced by how well the system capabilities are conveyed to the user. When interacting with the automation system, the user can obtain the system reliability information through an explicit description of the reliability or through experiencing the system over time. The term description-experience gap illustrates the difference between description-based and experience-based human decisions. In the current study, we investigated how this description-experience gap applies to human-automation interaction with a phishing-detection task in the cyber domain. In two experiments, participants’ performance in detecting phishing emails and their trust in the phishing detection system were measured when system reliability, description, and experience (i.e., feedback) were varied systematically in easy and difficult phishing detection tasks. The results suggested that system reliability had a profound influence on human performance in the system, but the benefits of having a more reliable system may depend on task difficulty. Also, providing feedback increased trust calibration in terms of both objective and subjective trust measures, yet providing description of system reliability increased only subjective trust. This result pattern not only shows the gap in the effects of feedback and description, but it also extends the description-experience gap concept from rare events to common events. [ABSTRACT FROM AUTHOR]

In this communication, we have discussed and compared the different drying processes i.e. flat plate solar collector, open sun and mechanical dryer with the preservative solution of Sodium Benzoate. Loquats were pretreated with preservative solution and subject to the drying process. Drying kinetics in terms of moisture lost per hour and drying rate, texture and antioxidants retention were determined before and after drying. Statistical analysis of the data showed that the different drying process has significantly affected on the kinetics of loquat fruits with the confidence interval of (α ≤ 0.05), whereas the preservative solution showed a non-significant effect on texture and antioxidants retention. High moisture lost per hour (5.4%) was recorded in mechanical dryer followed by flat plate solar collector dryer (3.7 %) while minimum (1.8%) was recorded in open sun drying. Good textured dried loquat with optimum hardness (313 g) and stiffness (141 g mm−1) was found in flat plate solar collector dried samples. Similarly more antioxidants (52%) retained in samples dried with hot air using flat plate solar collector followed by the mechanical dryer (47%) while minimum (41%) was recorded in open sun drying. Although mechanical drying is fast, it does not help to maintain a good texture and more antioxidants. From the study, it was concluded that hot air drying using a flat plate solar collector is better for drying process to get valuable dried loquat with good texture and more antioxidants. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the effectiveness of domain highlighting in helping users identify whether Web pages are legitimate or spurious.Background: As a component of the URL, a domain name can be overlooked. Consequently, browsers highlight the domain name to help users identify which Web site they are visiting. Nevertheless, few studies have assessed the effectiveness of domain highlighting, and the only formal study confounded highlighting with instructions to look at the address bar.Method: We conducted two phishing detection experiments. Experiment 1 was run online: Participants judged the legitimacy of Web pages in two phases. In Phase 1, participants were to judge the legitimacy based on any information on the Web page, whereas in Phase 2, they were to focus on the address bar. Whether the domain was highlighted was also varied. Experiment 2 was conducted similarly but with participants in a laboratory setting, which allowed tracking of fixations.Results: Participants differentiated the legitimate and fraudulent Web pages better than chance. There was some benefit of attending to the address bar, but domain highlighting did not provide effective protection against phishing attacks. Analysis of eye-gaze fixation measures was in agreement with the task performance, but heat-map results revealed that participants' visual attention was attracted by the highlighted domains.Conclusion: Failure to detect many fraudulent Web pages even when the domain was highlighted implies that users lacked knowledge of Web page security cues or how to use those cues.Application: Potential applications include development of phishing prevention training incorporating domain highlighting with other methods to help users identify phishing Web pages. [ABSTRACT FROM AUTHOR]

Policy integration and inter-operation is often a crucial requirement when parties with different access control policies need to participate in collaborative applications and coalitions. Such requirement is even more difficult to address for dynamic large-scale collaborations, in which the number of access control policies to analyze and compare can be quite large. An important step in policy integration and inter-operation is to analyze the similarity of policies. Policy similarity can sometimes also be a pre-condition for establishing a collaboration, in that a party may enter a collaboration with another party only if the policies enforced by the other party match or are very close to its own policies. Existing approaches to the problem of analyzing and comparing access control policies are very limited, in that they only deal with some special cases. By recognizing that a suitable approach to the policy analysis and comparison requires combining different approaches, we propose in this paper a comprehensive environment—EXAM. The environment supports various types of analysis query, which we categorize in the paper. A key component of such environment, on which we focus in the paper, is the policy analyzer able to perform several types of analysis. Specifically, our policy analyzer combines the advantages of existing MTBDD-based and SAT-solver-based techniques. Our experimental results, also reported in the paper, demonstrate the efficiency of our analyzer. [ABSTRACT FROM AUTHOR]

The Chinese Ocean Color and Temperature Scanner (COCTS) onboard the Haiyang-1C (HY-1C) satellite was launched in September 2018. Accurate and stable calibration is one of the important factors when deriving geophysical parameters with high quality. The first assessment of HY-1C COCTS thermal infrared calibration is conducted in this research. We choose the Infrared Atmospheric Sounding Interferometer (IASI) onboard the MetOp-B satellite as the reference instrument, mainly due to its hyper-spectral characteristic and accurate calibration superiority. The brightness temperatures (BTs) from the two HY-1C COCTS thermal infrared bands centered near 11 and 12 µm are collocated with the IASI in the spatial window of 0.12° × 0.12° and temporal window of half an hour. The homogeneity filtering of matchups is also carried out by setting the relative standard deviation (RSD) thresholds on each collocated grid and its neighboring grids. Based on the filtered matchups, the HY-1C COCTS BTs from the 11 and 12 µm channels are compared with IASI. The mean differences of COCTS minus IASI are 2.68 and 3.18 K for the 11 and 12 μm channels, respectively. The corresponding standard deviations (SDs) are also 0.29 and 0.28 K, respectively. In addition, the BT differences show latitude-dependence and BT-dependence. In order to correct the HY-1C COCTS thermal infrared BTs, the latitude-dependent coefficients are obtained to express the relationship between the BT differences and IASI BTs using the linear robust regression. After the BT correction, the biases and BT-dependence of the COCTS original BT minus IASI differences are removed. Further, the SDs decrease to 0.21 K for the 11 and 12 μm channels. Overall, the calibration of the HY-1C COCTS thermal infrared channels remains stable and the accuracy is around 0.2 K after inter-calibration. [ABSTRACT FROM AUTHOR]