The article introduces an approach combining diffusion approximation and simulation ones. Furthermore, it describes how it can be used to evaluate active queue management (AQM) mechanisms. Based on the obtained queue distributions, the simulation part of the model decides on package losses and modifies the flow intensity sent by the transmitter. The diffusion is used to estimate queue distributions

According to its planning scope, path planning for unmanned surface vehicle (USV) can be divided into global and local path planning. Many scholars have improved the classic algorithms, including grids method, visibility graph method, A* algorithm and artificial potential field method (APF), But the global planning algorithm still has outstanding problems such as long calculation time and large computational

Due to rapid increase rate of smart medical devices, the existing security internet of things (IoT) protocols cannot guaranty to perform better in-term of various threats. In this paper, the Secure Addressing and Mutual Authentication protocol (SAMA) scheme is proposed to protect the network from multiple attacks. The SAMA scheme uses the unique addressing and identification method to authenticates

The existence of one-way functions seems to depend, intuitively, on certain irregular properties of polynomial-time computable functions. Therefore, for functions with continuity properties, it suggests that all such functions are not one-way. It is shown here that in the formal complexity theory of real functions, this nonexistence of continuous one-way functions can be proved for one-to-one one-dimensional

In this paper we consider the digraph width measures directed path-width, directed tree-width, directed feedback vertex set number, directed feedback arc set number, cycle rank, DAG-depth, DAG-width and Kelly-width of recursively defined digraphs. While the minimization problem for these width measures is generally NP-hard, we prove that it is computable in linear time for all these parameters, except

We introduce a notion of coded equivalence in one-sided topological Markov shifts. The notion is inspired by coding theory. One-sided topological conjugacy implies coded equivalence. We will show that coded equivalence implies continuous orbit equivalence of one-sided topological Markov shifts.

We propose two fixed-parameter tractable algorithms for the weighted Max-Cut problem on embedded 1-planar graphs parameterized by the crossing number k of the given embedding. A graph is called 1-planar if it can be drawn in the plane with at most one crossing per edge. Our algorithms recursively reduce a 1-planar graph to at most 3k planar graphs, using edge removal and node contraction. Our main

In digital systems such as fiber optical communications, the ratio between probability of errors of type 1→0 and 0→1 can be large. Practically, one can assume that only one type of error can occur. These errors are called asymmetric. Unidirectional errors differ from asymmetric type of errors; here both 1→0 and 0→1 type of errors are possible, but in any submitted codeword all the errors are of the

A tessellation of a graph is a partition of its vertices into cliques. A tessellation cover of a graph is a set of tessellations that covers all of its edges, and the tessellation cover number, denoted by T(G), is the size of a smallest tessellation cover. The t-tessellability problem aims to decide whether a graph G has T(G)≤t. The number of edges of a maximum induced star of G, denoted by s(G), is

Updating and querying on a range is a classical algorithmic problem with a multitude of applications. The Segment Tree data structure is particularly notable in handling the range query and update operations. A Segment Tree divides the range into disjoint segments and merges them together to perform range queries and range updates elegantly. Although this data structure is remarkably potent for 1-dimensional

We consider a scheduling game on parallel related machines, in which jobs try to minimize their completion time by choosing a machine to be processed on. Each machine uses an individual priority list to decide on the order according to which the jobs on the machine are processed. We prove that it is NP-hard to decide if a pure Nash equilibrium exists and characterize four classes of instances in which

Cybersecurity mainly prevents the hardware, software, and data present in the system that has an active internet connection from external attacks. Organizations mainly deploy cybersecurity for their databases and systems to prevent it from unauthorized access. Different forms of attacks like phishing, spear-phishing, a drive-by attack, a password attack, denial of service, etc. are responsible for

Optimal codebooks meeting the Welch bound with equality are desirable in many areas, such as direct spread code division multiple access communications, compressed sensing and so on. However, it is difficult to construct such optimal codebooks. There have been a number of attempts to construct codebooks nearly meeting the Welch bound. In this paper, we introduce a generic construction of codebooks

The need to forecast COVID-19 related variables continues to be pressing as the epidemic unfolds. Different efforts have been made, with compartmental models in epidemiology and statistical models such as AutoRegressive Integrated Moving Average (ARIMA), Exponential Smoothing (ETS) or computing intelligence models. These efforts have proved useful in some instances by allowing decision makers to distinguish

In the aftermath of the COVID-19 pandemic, supply chains experienced an unprecedented challenge to fulfill consumers’ demand. As a vital operational component, manual order picking operations are highly prone to infection spread among the workers, and thus, susceptible to interruption. This study revisits the well-known order batching problem by considering a new overlap objective that measures the

This paper presents a new trial to reproduce soil stress–strain behaviour by adapting a long short-term memory (LSTM) deep learning method. LSTM is an approach that employs time sequence data to predict future occurrences, and it can be used to consider the stress history of soil behaviour. The proposed LSTM method includes the following three steps: data preparation, architecture determination, and

The least squares based affine projection algorithm (APA) is sensitive to outliers/impulsive noise in the desired data. A novel robust APA over distributed networks scenario is proposed in this manuscript, which is based on the rank based robust estimator named Wilcoxon norm. The proposed diffusion Wilcoxon affine projection algorithm (DWx-APA) based on pseudo least squares formulation is robust against

Sparse Code Multiple Access (SCMA) is a multi-dimensional codebook based on a class of Non-Orthogonal Multiple Access (NOMA) to provide many users through non-orthogonal resource elements without detection complexity in 5G wireless communications. The codebook design is one of the main criteria in SCMA downlink systems. This paper proposes an efficient SCMA joint codebook design and assignment model

Mining ponds move the toxic element into the food web.

Most funders have no plans to provide postdoctoral researchers with additional pandemic funding. Society will pay a high price if this neglect continues.

Despite having a steep learning curve, the programming language offers speed and safety.

The explosively expanding COVID-19 pandemic urges the development of safe, efficacious and fast-acting vaccines. Several vaccine platforms are leveraged for a rapid emergency response1. We describe the discovery of a live virus-vectored SARS-CoV-2 vaccine candidate using the yellow fever 17D (YF17D) vaccine as vector to express a non-cleavable prefusion form of the SARS-CoV-2 Spike antigen. We assess

Why do stone, bronze, iron, oil and data get all the attention?

Nature’s first-ever survey of this key segment of the scientific workforce uncovers anxiety and doubt about their professional pathway.

CubeSat-based nanosatellites are composed of COTS components and rely on its structure and standardized interfaces. A challenge in the nanosatellites context is to adapt the V\&V (Verification and Validation) process to answer to the increase importance of the embedded software, to reduce the artefacts to be delivered aiming at cutting cost and time and still complying with international standards

Policy responses to the COVID-19 outbreak must strike a balance between maintaining essential supply chains and limiting the spread of the virus. Our results indicate a strong positive relationship between livestock-processing plants and local community transmission of COVID-19, suggesting that these plants may act as transmission vectors into the surrounding population and accelerate the spread of

The COVID-19 pandemic is caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and has spread worldwide, with millions of cases and more than 1 million deaths to date. The gravity of the situation mandates accelerated efforts to identify safe and effective vaccines. Here, we generated measles virus (MeV)-based vaccine candidates expressing the SARS-CoV-2 spike glycoprotein (S). Insertion

One of the primary ways we interact with the world is using our hands. In macaques, the circuit spanning the anterior intraparietal area, the hand area of the ventral premotor cortex, and the primary motor cortex is necessary for transforming visual information into grasping movements. However, no comprehensive model exists that links all steps of processing from vision to action. We hypothesized that

The universally conserved Sec system is the primary method cells utilize to transport proteins across membranes. Until recently, measuring the activity—a prerequisite for understanding how biological systems work—has been limited to discontinuous protein transport assays with poor time resolution or reported by large, nonnatural tags that perturb the process. The development of an assay based on a

Anxiety commonly co‐occurs with obsessive-compulsive disorder (OCD). Both of them are closely related to stress. However, the shared neurobiological substrates and therapeutic targets remain unclear. Here we report an amelioration of both anxiety and OCD via the histamine presynaptic H3 heteroreceptor on glutamatergic afferent terminals from the prelimbic prefrontal cortex (PrL) to the nucleus accumbens

Widespread seafloor methane venting has been reported in many regions of the world oceans in the past decade. Identifying and quantifying where and how much methane is being released into the ocean remains a major challenge and a critical gap in assessing the global carbon budget and predicting future climate [C. Ruppel, J. D. Kessler. Rev. Geophys. 55, 126–168 (2017)]. Methane hydrate (CH4⋅5.75H2O)

We consider disordered solids in which the microscopic elements can deform plastically in response to stresses on them. We show that by driving the system periodically, this plasticity can be exploited to train in desired elastic properties, both in the global moduli and in local “allosteric” interactions. Periodic driving can couple an applied “source” strain to a “target” strain over a path in the

We report on in vitro wound-healing and cell-growth studies under the influence of radio-frequency (rf) cell stimuli. These stimuli are supplied either by piezoactive surface acoustic waves (SAWs) or by microelectrode-generated electric fields, both at frequencies around 100 MHz. Employing live-cell imaging, we studied the time- and power-dependent healing of artificial wounds on a piezoelectric chip

Disease tolerance, the capacity of tissues to withstand damage caused by a stimulus without a decline in host fitness, varies across tissues, environmental conditions, and physiologic states. While disease tolerance is a known strategy of host defense, its role in noninfectious diseases has been understudied. Here, we provide evidence that a thermogenic fat–epithelial cell axis regulates intestinal

TIA1, a protein critical for eukaryotic stress response and stress granule formation, is structurally characterized in full-length form. TIA1 contains three RNA recognition motifs (RRMs) and a C-terminal low-complexity domain, sometimes referred to as a “prion-related domain” or associated with amyloid formation. Under mild conditions, full-length (fl) mouse TIA1 spontaneously oligomerizes to form

Streamlined characterization of protein complexes remains a challenge for the study of protein interaction networks. Here we describe serial capture affinity purification (SCAP), in which two separate proteins are tagged with either the HaloTag or the SNAP-tag, permitting a multistep affinity enrichment of specific protein complexes. The multifunctional capabilities of this protein-tagging system also

The stereotyped dimensions of animal bodies and their component parts result from tight constraints on growth. Yet, the mechanisms that stop growth when organs reach the right size are unknown. Growth of the Drosophila wing—a classic paradigm—is governed by two morphogens, Decapentaplegic (Dpp, a BMP) and Wingless (Wg, a Wnt). Wing growth during larval life ceases when the primordium attains full size

Numerous studies demonstrate that neuroinflammation is a key player in the progression of Alzheimer’s disease (AD). Interleukin (IL)-1β is a main inducer of inflammation and therefore a prime target for therapeutic options. The inactive IL-1β precursor requires processing by the the nucleotide-binding oligomerization domain-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome into a

In the late 1990s, Se-Jin Lee was exploring the effects of regulatory genes in mice when he found a gene with a remarkable phenotype (1). “These mice have a doubling of muscle mass throughout the body,” says Lee. He had been identifying and characterizing new members of the TGF-β family of signaling proteins that he called growth/differentiation factors (GDFs) and had knocked out various GDFs in mice

With ∼36,000 described species, Agaricomycetes are among the most successful groups of Fungi. Agaricomycetes display great diversity in fruiting body forms and nutritional modes. Most have pileate-stipitate fruiting bodies (with a cap and stalk), but the group also contains crust-like resupinate fungi, polypores, coral fungi, and gasteroid forms (e.g., puffballs and stinkhorns). Some Agaricomycetes

MNRR1 (CHCHD2) is a bi-organellar regulator of mitochondrial function that directly activates cytochrome c oxidase in the mitochondria and functions in the nucleus as a transcriptional activator for hundreds of genes. Since MNRR1 depletion contains features of a mitochondrial disease phenotype, we evaluated the effects of forced expression of MNRR1 on the mitochondrial disease MELAS (mitochondrial

Molybdenum sulfide (MoS2) is the most widely studied transition-metal dichalcogenide (TMDs) and phase engineering can markedly improve its electrocatalytic activity. However, the selectivity toward desired products remains poorly explored, limiting its application in complex chemical reactions. Here we report how phase engineering of MoS2 significantly improves the selectivity for nitrite reduction

Inhibiting membrane association of RAS has long been considered a rational approach to anticancer therapy, which led to the development of farnesyltransferase inhibitors (FTIs). However, FTIs proved ineffective against KRAS-driven tumors. To reveal alternative therapeutic strategies, we carried out a genome-wide CRISPR-Cas9 screen designed to identify genes required for KRAS4B membrane association

The deadly symptoms of malaria occur as Plasmodium parasites replicate within blood cells. Members of several variant surface protein families are expressed on infected blood cell surfaces. Of these, the largest and most ubiquitous are the Plasmodium-interspersed repeat (PIR) proteins, with more than 1,000 variants in some genomes. Their functions are mysterious, but differential pir gene expression

The three members of the endocrine-fibroblast growth factor (FGF) family, FGF19, 21, and 23 are circulating hormones that regulate critical metabolic processes. FGF23 stimulates the assembly of a signaling complex composed of α-Klotho (KLA) and FGF receptor (FGFR) resulting in kinase activation, regulation of phosphate homeostasis, and vitamin D levels. Here we report that the C-terminal tail of FGF23

Social influences on decision-making are particularly pronounced during adolescence and have both protective and detrimental effects. To evaluate how responsiveness to social signals may be linked to substance use in adolescents, we used functional neuroimaging and a gambling task in which adolescents who have and have not used substances (substance-exposed and substance-naïve, respectively) made choices

TAT-RasGAP317–326 is a cell-penetrating peptide-based construct with anticancer and antimicrobial activities. This peptide kills a subset of cancer cells in a manner that does not involve known programmed cell death pathways. Here we have elucidated the mode of action allowing TAT-RasGAP317–326 to kill cells. This peptide binds and disrupts artificial membranes containing lipids typically enriched

Recent evidence suggests a link between visual motion processing and social cognition. When person A watches person B, the brain of A apparently generates a fictitious, subthreshold motion signal streaming from B to the object of B’s attention. These previous studies, being correlative, were unable to establish any functional role for the false motion signals. Here, we directly tested whether subthreshold

Pericentromeric human satellite II (HSATII) repeats are normally silent but can be actively transcribed in tumor cells, where increased HSATII copy number is associated with a poor prognosis in colon cancer, and in human cytomegalovirus (HCMV)-infected fibroblasts, where the RNA facilitates viral replication. Here, we report that HCMV infection or treatment of ARPE-19 diploid epithelial cells with

Human sapoviruses (HuSaVs) cause acute gastroenteritis similar to human noroviruses. Although HuSaVs were discovered four decades ago, no HuSaV has been grown in vitro, which has significantly impeded the understanding of viral biology and the development of antiviral strategies. In this study, we identified two susceptible human cell lines, that originated from testis and duodenum, that support HuSaV

Proteostasis collapse, the diminished ability to maintain protein homeostasis, has been established as a hallmark of nematode aging. However, whether proteostasis collapse occurs in humans has remained unclear. Here, we demonstrate that proteostasis decline is intrinsic to human senescence. Using transcriptome-wide characterization of gene expression, splicing, and translation, we found a significant

Obligate symbioses involving intracellular bacteria have transformed eukaryotic life, from providing aerobic respiration and photosynthesis to enabling colonization of previously inaccessible niches, such as feeding on xylem and phloem, and surviving in deep-sea hydrothermal vents. A major challenge in the study of obligate symbioses is to understand how they arise. Because the best studied obligate

The β2 adrenergic receptor (β2AR) is an archetypal G protein coupled receptor (GPCR). One structural signature of GPCR activation is a large-scale movement (ca. 6 to 14 Å) of transmembrane helix 6 (TM6) to a conformation which binds and activates a cognate G protein. The β2AR exhibits a low level of agonist-independent G protein activation. The structural origin of this basal activity and its suppression

Seasonal cycles govern life on earth, from setting the time for the mating season to influencing migrations and governing physiological conditions like hibernation. The effect of such changing conditions on behavior is well-appreciated, but their impact on the brain remains virtually unknown. We investigate long-term seasonal changes in the mammalian brain, known as Dehnel’s effect, where animals exhibit

Cell biologist Sandra L. Schmid has compared some of her skills to that of a watchmaker. “I like to take things apart, put them back together, and understand exactly how they work,” she explained in an essay commemorating the American Society for Cell Biology’s 50th anniversary (1). For much of the past 40 years, she has uncovered the molecular mechanisms and regulation of clathrin-mediated endocytosis

We introduce MTT, a dependent type theory which supports multiple modalities. MTT is parametrized by a mode theory which specifies a collection of modes, modalities, and transformations between them. We show that different choices of mode theory allow us to use the same type theory to compute and reason in many modal situations, including guarded recursion, axiomatic cohesion, and parametric quantification

It is well established that equational algebraic theories, and the monads they generate, can be used to encode computational effects. An important insight of Power and Shkaravska is that comodels of an algebraic theory T -- i.e., models in the opposite category Set^op -- provide a suitable environment for evaluating the computational effects encoded by T. As already noted by Power and Shkaravska, taking

Cartesian difference categories are a recent generalisation of Cartesian differential categories which introduce a notion of "infinitesimal" arrows satisfying an analogue of the Kock-Lawvere axiom, with the axioms of a Cartesian differential category being satisfied only "up to an infinitesimal perturbation". In this work, we construct a simply-typed calculus in the spirit of the differential lambda-calculus

Like notions of process equivalence, behavioural preorders on processes come in many flavours, ranging from fine-grained comparisons such as ready simulation to coarse-grained ones such as trace inclusion. Often, such behavioural preorders are characterized in terms of theory inclusion in dedicated characteristic logics; e.g. simulation is characterized by theory inclusion in the positive fragment

We introduce PHFL, a probabilistic extension of higher-order fixpoint logic, which can also be regarded as a higher-order extension of probabilistic temporal logics such as PCTL and the $\mu^p$-calculus. We show that PHFL is strictly more expressive than the $\mu^p$-calculus, and that the PHFL model-checking problem for finite Markov chains is undecidable even for the $\mu$-only, order-1 fragment of