A closer look at adaptive regret

For the prediction with expert advice setting, we consider methods to construct algorithms that have low adaptive regret. The adaptive regret of an algorithm on a time interval [t1,t2] is the loss of the algorithm minus the loss of the best expert over that interval. Adaptive regret measures how well the algorithm approximates the best expert locally, and so is different from, although closely related to, both the classical regret, measured over an initial time interval [1,t], and the tracking regret, where the algorithm is compared to a good sequence of experts over [1,t]. We investigate two existing intuitive methods for deriving algorithms with low adaptive regret, one based on specialist experts and the other based on restarts. Quite surprisingly, we show that both methods lead to the same algorithm, namely Fixed Share, which is known for its tracking regret. We provide a thorough analysis of the adaptive regret of Fixed Share. We obtain the exact worst-case adaptive regret for Fixed Share, from which the classical tracking bounds follow. We prove that Fixed Share is optimal for adaptive regret: the worst-case adaptive regret of any algorithm is at least that of an instance of Fixed Share

Atomic Force Microscopy Investigation of DNA Extracted from the Vegetative Forms and the Viable but Nonculturable Forms of Mycoplasma gallisepticum

Recent studies show that mycoplasmas have various programs of life. This means that changes in morphology and genome expression may occur once the environment of these microorganisms becomes extremely altered. In this article, we report on changes in the DNA molecule obtained from the vegetative forms and the viable but nonculturable (VBNC) forms of Mycoplasma gallisepticum S6. Atomic force microscopy studies show that the above-mentioned forms of the mycoplasma have different values of DNA parameters (height: 0.461 ± 0.141 and 0.236 ± 0.069 nm; width: 2.221 ± 0.286 and 1.291 ± 0.705 nm for the vegetative and the VBNC forms, respectively). We suppose that the observed phenomenon may be connected with the process of adaptation of these bacteria to severe environments

Methods of contactless registration of information signals for the audit of information security of power supply systems and networks

It is known that there is an information signal in power supply systems and networks. The presence of information signals in the power elements of power supply systems and networks (electrical signal) in combination with other information allows extracting secondary information from power supply systems and networks. In some cases, this kind of information is confidential, has a high level of significance, and power supply facilities may belong to critical information infrastructure facilities. Thus, auditing and ensuring information security of power supply systems and networks seem relevant. In this regard, the issues of identifying previously unaccounted for channels of possible leakage of confidential information, developing methods for contactless monitoring of information security of generation, transportation, transformation and electricity consumption facilities are important. A contactless method for recording and calculating spurious emissions in established operating modes and during transients in long lines is proposed by solving the inverse problem of calculating the currents of multi-wire long lines based on measuring their magnetic field, taking into account the principle of superposition. To implement the method in application to a Q-wire line, simultaneous measurement of the magnetic field at Q different points with known coordinates is required. It also requires knowledge of the coordinates of the wires with the length of the line. Geometric measurements are proposed to be implemented using laser rangefinders or scanners. When measuring the magnetic field of a long line, the quasi-constant component of the Earth’s magnetic field is taken into account. A method is proposed for determining the direction and delay of reflection of traveling waves in a long line, based on information from two magnetic field sensors located at a sufficient distance from each other along the line. Methods are proposed to ensure the audit and monitoring of the state of power supply systems and networks that are under the influence of threats to information security violations. Mathematical modeling of the proposed method of contactless current measurement in a long line and field experiments of current measurement in a long line and registration of traveling waves are performed. The experimental results show the accuracy of the proposed methods sufficient to solve the tasks. The work develops an idea of methods and means of ensuring audit and monitoring of information security of electrical systems and networks. The results of the work make it possible to identify new, previously unaccounted for channels of information leakage and to develop new contactless methods for registering information signals in power transmission lines

Extracellular Vesicles Derived from Acholeplasma laidlawii

Extracellular vesicle production is believed to be a ubiquitous process in bacteria, but the data on such a process in Mollicutes are absent. We report the isolation of ultramicroforms – extracellular vesicles from supernatants of Acholeplasma laidlawii PG8 (ubiquitous mycoplasma; the main contaminant of cell culture). Considering sizes, morphology, and ultrastructural organization, the ultramicroforms of A. laidlawii PG8 are similar to membrane vesicles of Gram-positive and Gram-negative bacteria. We demonstrate that A. laidlawii PG8 vesicles contain genetic material and proteins, and are mutagenic to lymphocytes of human peripheral blood. We show that Mycoplasma gallisepticum S6, the other mycoplasma, also produce similar structures, which suggests that shedding of the vesicles might be the common phenomenon in Mollicutes. We found that the action of stress conditions results in the intensive formation of ultramicroforms in mycoplasmas. The role of vesicular formation in mycoplasmas remains to be studied

CCR5/CXCR3 antagonist TAK-779 prevents diffuse alveolar damage of the lung in the murine model of the acute respiratory distress syndrome

Introduction: The acute respiratory distress syndrome (ARDS), secondary to viral pneumonitis, is one of the main causes of high mortality in patients with COVID-19 (novel coronavirus disease 2019)—ongoing SARS-CoV-2 infection— reached more than 0.7 billion registered cases.Methods: Recently, we elaborated a non-surgical and reproducible method of the unilateral total diffuse alveolar damage (DAD) of the left lung in ICR mice–a publicly available imitation of the ARDS caused by SARS-CoV-2. Our data read that two C–C chemokine receptor 5 (CCR5) ligands, macrophage inflammatory proteins (MIPs) MIP-1α/CCL3 and MIP-1β/CCL4, are upregulated in this DAD model up to three orders of magnitude compared to the background level.Results: Here, we showed that a nonpeptide compound TAK-779, an antagonist of CCR5/CXCR3, readily prevents DAD in the lung with a single injection of 2.5 mg/kg. Histological analysis revealed reduced peribronchial and perivascular mononuclear infiltration in the lung and mononuclear infiltration of the wall and lumen of the alveoli in the TAK-779-treated animals. Administration of TAK-779 decreased the 3–5-fold level of serum cytokines and chemokines in animals with DAD, including CCR5 ligands MIP-1α/β, MCP-1, and CCL5. Computed tomography revealed rapid recovery of the density and volume of the affected lung in TAK-779-treated animals.Discussion: Our pre-clinical data suggest that TAK-779 is more effective than the administration of dexamethasone or the anti-IL6R therapeutic antibody tocilizumab, which brings novel therapeutic modality to TAK-779 and other CCR5 inhibitors for the treatment of virus-induced hyperinflammation syndromes, including COVID-19

Formation of Amyloid-Like Fibrils by Y-Box Binding Protein 1 (YB-1) Is Mediated by Its Cold Shock Domain and Modulated by Disordered Terminal Domains

YB-1, a multifunctional DNA- and RNA-binding nucleocytoplasmic protein, is involved in the majority of DNA- and mRNA-dependent events in the cell. It consists of three structurally different domains: its central cold shock domain has the structure of a β-barrel, while the flanking domains are predicted to be intrinsically disordered. Recently, we showed that YB-1 is capable of forming elongated fibrils under high ionic strength conditions. Here we report that it is the cold shock domain that is responsible for formation of YB-1 fibrils, while the terminal domains differentially modulate this process depending on salt conditions. We demonstrate that YB-1 fibrils have amyloid-like features, including affinity for specific dyes and a typical X-ray diffraction pattern, and that in contrast to most of amyloids, they disassemble under nearly physiological conditions

Non-Standard Errors

In statistics, samples are drawn from a population in a data-generating process (DGP). Standard errors measure the uncertainty in estimates of population parameters. In science, evidence is generated to test hypotheses in an evidence-generating process (EGP). We claim that EGP variation across researchers adds uncertainty: Non-standard errors (NSEs). We study NSEs by letting 164 teams test the same hypotheses on the same data. NSEs turn out to be sizable, but smaller for better reproducible or higher rated research. Adding peer-review stages reduces NSEs. We further find that this type of uncertainty is underestimated by participants