Search Results (20,655)

Two new heteroleptic cobalt(II) complexes (3,6-Cat)Co(R-DAD) (where (3,6-Cat)²⁻ is a dianion of 3,6-di-tert-butyl-o-benzoquinone, R-DAD is diisopropyl-1,4-diaza-1,3-butadiene (R = i-Pr (1)) or dicyclohexyl-1,4-diaza-1,3-butadiene (R = c-Hex (2)) have been synthesized and characterized in detail by IR, UV–Vis–NIR spectroscopy, and elemental analysis. The molecular structure of 1 was determined by X-ray diffraction analysis. Magnetic properties of 1 and 2 were measured both in a solid state and in a solution. According to the single-crystal X-ray diffraction analysis, the metal ion in 1 has a planar coordination environment, but magnetic susceptibility measurements of the microcrystalline samples of 1 and 2 indicate the formation of both forms with tetrahedral (d⁷, h.s., S_Co = 3/2) and planar (d⁷, l.s., S_Co = ½) coordination environments of the metal ion. Absorption spectra of crystalline samples of 1 and 2 possess intense absorption band in the NIR region. Electrochemical measurements of 1 and 2 were also performed. Full article

An analysis of the international radon regulatory framework identified actual challenges for the design and conduct of indoor radon surveys, though there is little discussion on this issue in the radon community. The main challenges hindering the development of radon regulation on an international scale, particularly in indoor radon surveys include the following: (i) responsibility for indoor radon testing and mitigation, (ii) excessive focus on Radon Priority Areas, (iii) the role of temporal uncertainty in indoor radon testing, (iv) the standardization of indoor radon measurements, and (v) the standardization of thoron EEC measurements and indoor testing. To address these gaps and inconsistencies, actual needs for design and conduct of indoor radon surveys are proposed, covering the aforementioned challenges. The needs statement, including a discussion of solutions, addresses the following key aspects of radon regulation: (1) legislation, (2) radon measurements, (3) awareness, and (4) building protection. The focus remains on the radon measurement aspect, detailing the strategy and tools for conducting indoor radon surveys within a rational approach. This includes the main research activities necessary for the sustainable development of global radon regulation. The final part of the article presents a Rational Method (protocol) of indoor radon measurements serving as a detailed guideline for standardizing indoor radon testing at the international level. This ensures the decision-making reliability of at least 95% and harmonizes relevant national approaches considering traditional measurement protocols using both short-term and long-term measurements. The proposed solutions aim to achieve the goal of a modern design and conduct of indoor radon surveys that are consistent with large-scale (mass) testing and effectively identify hazardous buildings. These solutions are based on a rational approach with convenient tools and active voluntary participation of the population to be implemented within the framework of national radon regulation. Full article

One new genus and five new species of the extinct family Maimetshidae from mid-Cretaceous Kachin amber are described based on five well-preserved specimens as follows: Maimetshasia nova Li, Kopylov and Rasnitsyn, sp. nov.; Maimetshasia engeli Li, Kopylov and Rasnitsyn, sp. nov.; Guyotemaimetsha perrichoti Li, Kopylov and Rasnitsyn, sp. nov.; Guyotemaimetsha ortegablancoi Li, Kopylov and Rasnitsyn, sp. nov.; and Crucimaimetsha nigra Li, Kopylov and Rasnitsyn, sp. nov. A new generic synonymy is proposed: Turgonalus Rasnitsyn, 1990 (= Turgonaliscus Engel, 2016, syn. nov. and = Ahiromaimetsha Perrichot, Azar, Nel and Engel, 2011, syn. nov.); Guyotemaimetsha Perrichot, Nel and Néraudeau, 2004 (= Burmaimetsha Perrichot, 2013, syn. nov.); Afrapia, Rasnitsyn and Brothers, 2009 (= Afromaimetsha, Rasnitsyn and Brothers, 2009, syn. nov.); and Iberomaimetsha nihtmara Ortega-Blanco, Delclòs and Engel, 2011 are transferred to Afrapia, Rasnitsyn and Brothers, 2009. This results in the following new combinations: Turgonalus cooperi, Rasnitsyn and Jarzembowski, 1998, comb. resurr.; Turgonalus najlae (Perrichot, Azar, Nel & Engel, 2011), comb. nov; Afrapia robusta (Rasnitsyn & Brothers, 2009), comb. nov; and Afrapia nihtmara (Ortega-Blanco, Delclòs & Engel, 2011), comb. nov. The occurrence of various genera of Maimetshidae in amber and compression fossil and the morphological differences of the forewings in all the fossil species are provided, which highlights a high level of genus-level diversity among Mesozoic maimetshids. The key to genera was updated. Full article

Reductive stress (RS), characterized by excessive accumulation of reducing equivalents such as NADH and NADPH, is emerging as a key factor in metabolic disorders and cancer. While oxidative stress (OS) has been widely studied, RS and its complex interplay with endocrine regulation remain less understood. This review explores molecular circuits of bidirectional crosstalk between metabolic hormones and RS, focusing on their role in diabetes, obesity, cardiovascular diseases, and cancer. RS disrupts insulin secretion and signaling, exacerbates metabolic inflammation, and contributes to adipose tissue dysfunction, ultimately promoting insulin resistance. In cardiovascular diseases, RS alters vascular smooth muscle cell function and myocardial metabolism, influencing ischemia-reperfusion injury outcomes. In cancer, RS plays a dual role: it enhances tumor survival by buffering OS and promoting metabolic reprogramming, yet excessive RS can trigger proteotoxicity and mitochondrial dysfunction, leading to apoptosis. Recent studies have identified RS-targeting strategies, including redox-modulating therapies, nanomedicine, and drug repurposing, offering potential for novel treatments. However, challenges remain, particularly in distinguishing physiological RS from pathological conditions and in overcoming therapy-induced resistance. Future research should focus on developing selective RS biomarkers, optimizing therapeutic interventions, and exploring the role of RS in immune and endocrine regulation. Full article

Background: Cerebral cavernous malformations (CCMs) are vascular lesions linked to mutations in the CCM1, CCM2, and CCM3 genes, resulting in angiogenesis dysregulation. This case study highlights the clinical course of a child with severe CCMs and explores the genetic basis of the condition. Methods: We used comprehensive clinical assessment and magnetic resonance imaging (MRI) to monitor the patient’s neurological status and CCM progression and genetic analysis by whole-exome sequencing to identify mutations in CCM-related genes. Results: The patient presented with developmental delays, multiple CCMs, and recurrent hemorrhagic events, requiring five surgical interventions. Genetic analysis revealed a novel frameshift mutation in the PDCD10 gene. Despite surgical efforts, the patient developed significant disability by age 13. Conclusions: This case illustrates the aggressive clinical course associated with CCMs, particularly in patients with CCM3 mutations. It underscores the importance of genetic screening and monitoring in understanding hereditary CCM progression and guiding treatment strategies. Full article

A team of unmanned surface vehicles (USVs) travels with a bounded speed in an unknown corridor-like scene containing obstacles. USVs should line up at the right angle with the corridor and evenly spread themselves out to form a densest barrier across the corridor, and this barrier should move along the corridor with a given speed. Collisions between the USVs and the corridor walls, other obstacles, and among themselves must be avoided. In the fractions of the scene containing obstacles, the line formation should be preserved, but the demand for an even distribution is inevitably relaxed. This evenness should be automatically restored after such a fraction is fully traversed. Any USV is aware of the corridor direction and measures the relative coordinates of the objects that lie within a given finite sensing distance. USVs do not know the corridor’s width and the team’s size, cannot distinguish between the team-mates and fill different roles, and do not use communication devices. A computationally cheap control law is presented that attains the posed objectives when being individually run at every USV. The robustness of this law to losses of teammates and admissions of newcomers is justified. Its performance is demonstrated by mathematically rigorous non-local convergence results, computer simulation tests, and experiments with real robots. Full article

Bacterial antibiotic resistance represents a major healthcare problem. In 2019, 4.95 million deaths were associated with antibiotic resistance, and it is estimated that, by 2050, up to 3.8% of the global gross domestic product could be lost due to this problem. Methicillin-resistant Staphylococcus aureus is one of the leading sources of hospital-acquired infections associated with increased mortality, length of hospital stay, and higher cost of treatment. Here, we describe the de novo synthesis of a library of 22 triazeneindole derivatives with high activity against a wide panel of multidrug-resistant MRSA clinical isolates. Leading compound BX-SI043 (ethyl 6-fluoro-3-[pyrrolidin-1-yl-azo]-1H-indole-2-carboxylate) showed high activity (minimal inhibitory concentration range, 0.125–0.5 mg/L) against 41 multidrug-resistant MRSA strains, as well as relatively low in vitro cytotoxicity (selectivity index, 76) and in vivo acute toxicity (maximum tolerated dose, 600 mg/kg), via intragastric administration in rats. These data suggest that BX-SI043 is a promising drug candidate for the development a novel MRSA treatment. Full article

Background: This is a comparative metabolomic study of the medicinal plant Dryopteris fragrans (L.) Schott from the family Dryopteridaceae Herter (or Aspidiaceae Mett. ex Frank) growing under cold pole conditions in the Oymyakon region of the Republic of Sakha (Yakutia). Methods: The aerial parts of D. fragrans were subjected to extraction using supercritical CO₂ extraction and maceration methods. Several experimental conditions were investigated, including a pressure range of 50–300 bar and a temperature range of 31–60 °C. A 1% volume of ethanol was used as a co-solvent in the liquid phase of the extraction. Results: The most effective D. fragrans extraction conditions were 200 Bar pressure and a temperature of 55 °C. Tandem mass spectrometry was used to detect the target analytes. A total of 141 bioactive compounds (86 compounds from the polyphenol group and 55 compounds from other chemical groups) were tentatively identified in extracts of aerial parts of D. fragrans. Among these, thirty chemical constituents from the polyphenol group were identified for the first time. Other compound classes that were newly identified in D. fragrans include naphthoquinones (5,8-dihydroxy-6-methyl-2,3-dihydro-1,4-naphthoquinone, 1,8-dihydroxy-anthraquinone, 1,4,8-trihydroxyanthraquinone, chrysophanol, etc.), diterpenoids (tanshinone IIa, cryptotanshinone, isocryptotanshinone II, tanshinone IIb, etc.), polysaccharides, triterpenoids, and sesquiterpenes. Conclusions: These results highlight that D. fragrans is rich in bioactive compounds and put forward several newly detected compounds for further investigation. Full article

Long-term observations in wells make it possible to study changes in groundwater pressure/level during individual earthquakes (seismo-hydrogeodynamic effects—SHGEs) over a wide range of periods of their manifestation. Information on the morphological features and durations of the SHGEs together with data on earthquake parameters form the basis for creating the unique typifications of SHGEs for individual observation wells. With reliable verification, such SHGE typifications provide the practical use of well observation data to predict strong earthquakes and assess their impact on groundwater. During long-term (1996–2022) precision observations of pressure/water level variations in wells of the Petropavlovsk–Kamchatsky test site (Kamchatka Peninsula, northwest Pacific seismic belt), SHGE typifications describing the manifestations of various types of SHGEs at the earthquakes in ranges of magnitudes M_w = 5.0–9.1 and epicentral distances d_e = 80–14,600 km were developed. At the same time, the issue of verifying created SHGE typifications for individual wells in relation to the strongest and closest earthquakes, accompanied by noticeable tremors in the observation area, is relevant. On 3 April 2023, an earthquake, M_w = 6.6 (EQ), occurred at an epicentral distance d_e = 67–77 km from observation wells. Various changes in the groundwater pressure/level were recorded in the wells: oscillations and other short-term and long-term effects of seismic waves, coseismic jumps in water pressure caused by a change in the static stress state of water-bearing rocks during the formation of rupture in the earthquake source, and supposed hydrogeodynamic precursors. The EQ was used to verify the SHGE typifications for wells YuZ-5 and E-1 with the longest observation series of more than 25 years. In these wells, the seismo-hydrogeodynamic effects recorded during the EQ corresponded to the previously observed SHGE during the two strongest earthquakes with M_w = 7.2, d_e = 80 km and M_w = 7.8, d_e = 200 km. This correspondence is considered an example of the experimental verification of previously created SHGE typifications in individual wells in relation to the most powerful earthquakes in the wells’ area. Updated SHGE typifications for wells E-1 and YuZ-5 are presented, showing the patterns of water level/pressure changes in these wells depending on earthquake parameters and thereby increasing the practical significance of well observations for assessing earthquake consequences for groundwater, searching for hydrogeodynamic precursors and forecasting strong earthquakes. The features of the hydrogeodynamic precursor manifesting in the water level/pressure lowering with increased rates in well E-1 before earthquakes with M_w ≥ 5.0 at epicentral distances of up to 360 km are considered. A retrospective statistical analysis of the prognostic significance of this precursor showed that its use for earthquake forecasting increases the efficiency of predicting earthquakes with M_w ≥ 5.0 by 1.55 times and efficiency of predicting earthquakes with M_w ≥ 5.8 by 2.34 times compared to random guessing. This precursor was recorded during the 92 days before the EQ and was identified in real time with the issuance of an early prognostic conclusion on the possibility of a strong earthquake to the Kamchatka branch of the Russian Expert Council for Earthquake Forecasting. Full article

Mambalgins are peptide inhibitors of acid-sensing ion channels type 1 (ASIC1) with potent analgesic effects in models of inflammatory and neuropathic pain. To optimize recombinant peptide production and enhance pharmacological properties, we developed a mutant analog of mambalgin-1 (Mamb) through molecular modeling and site-directed mutagenesis. The resulting peptide, Mamb-AL, features methionine-to-alanine and methionine-to-leucine substitutions, allowing for a more efficient recombinant production protocol in E. coli. Electrophysiological experiments demonstrated that Mamb-AL exhibits three-fold and five-fold greater inhibition of homomeric ASIC1a and ASIC1b channels, respectively, and a two-fold increase in inhibition of heteromeric ASIC1a/3 channels compared with Mamb. In a mouse model of acetic acid-induced writhing pain, Mamb-AL showed a trend toward stronger analgesic efficacy than the wild-type peptide. These improvements in both production efficiency and pharmacological properties make Mamb-AL a valuable tool for studying ASIC channels and a promising candidate for analgesic drug development. Full article

A model of a “smart” composite based on a thermosensitive PNIPAM polymer deposited on a FeRh substrate with a modified periodic microstructure was proposed. The initial parameters of the model were determined from the properties of the actual composite sample and its components. Cooling of the sample using a magnetic field was shown by two independent methods, and at ~37 °C, it was −5.5 °C when a magnetic field of 1.8 T was applied. Based on experimental data, models of traditional and modified PNIPAM/FeRh composites were constructed. Calculations show that surface modification allows for an increase in the activation time for a polymer layer that is 20 µm thick from ~20 ms for a conventional composite to ~60 ms for a modified composite. Modification of the surface in the form of wells can be used to more effectively implement the idea of loading and releasing drugs for potential biomedical applications. Full article

Background: Tauopathy has been identified as a prevalent causative agent of neurodegenerative diseases, including frontotemporal dementia with parkinsonism-17 (FTDP-17). This rare hereditary neurodegenerative condition is characterised by the manifestation of parkinsonism and behavioural changes. The majority of cases of FTDP-17 are associated with mutations in the MAPT gene, which encodes the tau protein. MAPT mutations lead to disruption of the balance between 3R and 4R tau forms, which causes destabilisation of microtubules and impairment of cellular organelle functions, particularly mitochondrial dysfunction. The development of model systems and tools for studying the molecular, genetic, and biochemical mechanisms underlying FTDP-17 and testing therapies at the cellular level is an urgent necessity. Methods: In this study, we generated transgenic lines of induced pluripotent stem cells (iPSCs) from a patient carrying the pathogenic mutation c.2013T > G (rs63750756, p.N279K) of MAPT and a healthy donor. A doxycycline-controlled transgene of the genetically encoded biosensor MitoTimer was integrated into the AAVS1 locus of these cells. The MitoTimer biosensor allows for lifetime monitoring of the turnover of mitochondria in neuronal cells derived from directed iPSC differentiation. The fact that transcription of the transgene can be induced by doxycycline provides additional possibilities for pulse labelling of newly formed mitochondria. Results: Transgenic iPSC lines provide a unique tool to study the molecular and genetic mechanisms of FTDP-17 caused by the presence of the c.2013T > G (p.N279K) mutation, as well as to test potential drugs in vitro. Full article

This paper analyzes the impact of a single soft error on the performance of a synchronous and self-timed pipeline. A nuclear particle running through the integrated circuit body is considered the most probable soft error source. The existing estimates show that self-timed circuits offer an advantage in terms of single soft error tolerance. The paper proves these estimates on the basis of a comparative probability analysis of a critical fault in two types of pipelines. The mathematical models derived in the paper describe the probability of a critical fault depending on the circuit’s characteristics, its operating discipline, and the soft error parameters. The self-timed pipeline operates in accordance with a two-phase discipline, based on the request–acknowledge interaction within the pipeline’s stages, which provides it with increased immunity to soft errors. Quantitative calculations performed on the basis of the derived mathematical models show that the self-timed pipeline has about 6.1 times better tolerance to a single soft error in comparison to its synchronous counterpart. The obtained results are in good agreement with empirical estimates of the soft error tolerance level of synchronous and self-timed circuits. Full article

A novel, strictly aerobic, non-motile, and pink-pigmented bacterium, designated 7Alg 153^T, was isolated from the Pacific green alga Cladophora stimpsonii. Strain 7Alg 153^T was able to grow at 4–32 °C in the presence of 1.5–4% NaCl and hydrolyze L-tyrosine, gelatin, aesculin, Tweens 20, 40, and 80 and urea, as well as produce catalase, oxidase, and nitrate reductase. The novel strain 7Alg 153^T showed the highest similarity of 96.75% with Pseudaestuariivita rosea H15^T, followed by Thalassobius litorarius MME-075^T (96.60%), Thalassobius mangrovi GS-10^T (96.53%), Tritonibacter litoralis SM1979^T (96.45%), and Marivita cryptomonadis CL-SK44^T (96.38%), indicating that it belongs to the family Roseobacteraceae, the order Rhodobacteales, the class Alphaproteobacteria, and the phylum Pseudomonadota. The respiratory ubiquinone was Q-10. The main polar lipids were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine, two unidentified aminolipids, and one unidentified lipid. The predominant cellular fatty acids (>5%) were C_18:1 ω7c, C_16:0, C_18:0, and 11-methyl C_18:1 ω7c. The 7Alg 153^T genome is composed of a single circular chromosome of 3,786,800 bp and two circular plasmids of 53,157 bp and 37,459 bp, respectively. Pan-genome analysis showed that the 7Alg 153^T genome contains 33 genus-specific clusters spanning 92 genes. The COG20-annotated singletons were more often related to signal transduction mechanisms, cell membrane biogenesis, transcription, and transport, and the metabolism of amino acids. The complete photosynthetic gene cluster (PGC) for aerobic anoxygenic photosynthesis (AAP) was found on a 53 kb plasmid. Based on the phylogenetic evidence and phenotypic and chemotaxonomic characteristics, the novel isolate represents a novel genus and species within the family Roseobacteraceae, for which the name Algirhabdus cladophorae gen. nov., sp. nov. is proposed. The type strain is 7Alg 153^T (=KCTC 72606^T = KMM 6494^T). Full article

Erwinia are widely known as phytopathogenic bacteria, but among them, there are also plant-friendly strains that can promote plant growth (PGPR). The Erwinia-like strain OPT-41 was isolated from Triticum aestivum seedlings as a potential PGPR. The cells (0.9–1.3 × 1.5–3.1 µm) of this microorganism are Gram-negative, rod-shaped, motile (with peritrichous flagella), and non-spore- and non-capsule-forming. The 16S rRNA gene sequence analyses showed it is located in the Erwiniaceae family and has a pairwise similarity above the species delineation threshold of 98.65% with several of its members: Erwinia tasmaniensis (99.21%), Candidatus Pantoea bathycoeliae (98.93%), Pantoea agglomerans (98.87%), Erwinia endophytica (98.83%), Erwinia persicina (98.82%), Erwinia billingiae (98.76%) and Erwinia aphidicola (98.75%). Whole genome-based taxonomy performed on the Type (Strain) Genome Server clarified the status of strain OPT-41, detecting it as a potential new species in the genus Erwinia. The microorganism under study was the most closely related to the type strain of E. phyllosphaerae, demonstrating 27.2% similarity in dDDH, 83.44% similarity in OrthoANIu, and 1.9% difference in G+C content. The major fatty acids of strain OPT-41 were 9 C_16:1, C_14:0, and C_16:0. A combination of genome-based taxonomy and traditional polyphasic taxonomy clearly indicated that strain OPT-41 belongs to a novel Erwinia species, for which the name E. plantamica sp. nov was proposed. OPT-41 (=IBPPM 712=VKM B-3874D=CCTCC AB 2024361) has been designated as the type strain. In addition, OPT-41 was found to have low degradation potential for host plant pectins and proteins and be friendly in Triticum aestivum and Hordeum vulgare crops. Full article