Publications by authors named "MELNIK A"

Bioluminescence is a functional property used by many marine organisms for multilateral communications. In the Arabian Sea, the dinoflagellate Noctiluca scintillans (Macartney) Kofoid and Swezy, 1921, contributes gradually to the bioluminescent potential (BP) of the phytoplankton community. Experiments, field sampling, and remote sensing were employed, to estimate the seasonal variation of the BP and the abundance of cells in the northwestern Arabian Sea.

View Article and Find Full Text PDF

Objectives: The present study aimed to assess the effects of blackcurrant (BC) anthocyanins on concentrations of microbial-derived short-chain carboxylic acids (SCCAs) and metabolites of phytoestrogens. We then examined their associations with six-month changes in whole-body bone mineral density (BMD) and biomarkers of bone metabolism.

Methods: Fecal and blood samples from a pilot randomized controlled trial were collected and analyzed from 37 eligible peri- and early postmenopausal women aged 45-60 years who were randomized into one of three treatment groups consuming one placebo capsule (control), 392 mg BC (low BC) or 784 mg BC (high BC) daily for six months.

View Article and Find Full Text PDF

Nature's molecular diversity is not random but displays intricate organization stemming from biological necessity. Molecular networking connects metabolites with structural similarity, enabling molecular discoveries from mass spectrometry data using arbitrary similarity thresholds that can fracture natural metabolite families. We present molecular community networking (MCN), that optimizes connectivity for each metabolite, rescuing lost relationships and capturing otherwise "hidden" metabolite connections.

View Article and Find Full Text PDF

Our goal with this survey is to provide an overview of the state of the art deep learning methods for face generation and editing using StyleGAN. The survey covers the evolution of StyleGAN, from PGGAN to StyleGAN3, and explores relevant topics such as suitable metrics for training, different latent representations, GAN inversion to latent spaces of StyleGAN, face image editing, cross-domain face stylization, face restoration, and even Deepfake applications. We aim to provide an entry point into the field for readers that have basic knowledge about the field of deep learning and are looking for an accessible introduction and overview.

View Article and Find Full Text PDF

Despite the increasing availability of tandem mass spectrometry (MS/MS) community spectral libraries for untargeted metabolomics over the past decade, the majority of acquired MS/MS spectra remain uninterpreted. To further aid in interpreting unannotated spectra, we created a nearest neighbor suspect spectral library, consisting of 87,916 annotated MS/MS spectra derived from hundreds of millions of MS/MS spectra originating from published untargeted metabolomics experiments. Entries in this library, or "suspects," were derived from unannotated spectra that could be linked in a molecular network to an annotated spectrum.

View Article and Find Full Text PDF

In the last decade, Ficin, a proteolytic enzyme extracted from the latex sap of the wild fig tree, has been widely investigated as a promising tool for the treatment of microbial biofilms, wound healing, and oral care. Here we report the antibiofilm properties of the enzyme immobilized on soluble carboxymethyl chitosan (CMCh) and CMCh itself. Ficin was immobilized on CMCh with molecular weights of either 200, 350 or 600 kDa.

View Article and Find Full Text PDF
Article Synopsis
  • Detection dogs were trained to identify SARS-CoV-2 infections by sniffing armpit sweat, with samples collected from confirmed positive and negative patients.
  • After a training period of 2-3 months, the dogs exhibited high sensitivity (81%), specificity (98%), and accuracy (95%) in detecting the virus, with validation showing consistent performance.
  • The study found a unique scent in SARS-CoV-2 positive sweat linked to various volatiles, and a survey indicated strong public support for using these dogs as a reliable pre-screening tool alongside traditional PCR testing.
View Article and Find Full Text PDF

This paper presents the results of the development and testing of a secondary ion accelerator for the diagnostic complex of neutral particle analyzers at ITER. The accelerator is part of an analyzer designed to measure fluxes of neutral deuterium and tritium particles escaping from reactor plasma in a total range of 10-200 keV. The aim of the accelerator is to improve the signal/background ratio of the analyzer.

View Article and Find Full Text PDF

Introduction: Although pre/pro/postbiotics have become more prevalent in dermatologic and cosmetic fields, the mode of action when topically applied is largely unknown. A multi-omic approach was applied to decipher the impact of the skincare products with pre/postbiotics on skin microbiome and metabolome.

Methods: Subjects with dry skin applied a body wash and body lotion with or without pre/postbiotics for 6 weeks.

View Article and Find Full Text PDF

The work presents the findings of the laboratory and in situ studies of ctenophore Pleurobrachia pileus O.F. Müller, 1776 which have shown that this species has bioluminescent properties.

View Article and Find Full Text PDF

Mesoscale eddies of the ocean (with a characteristic diameter of about 100 km and a life time-span of about several weeks) are habitats of plankton organisms, many of which are bioluminescent. The spatial heterogeneity of bioluminescence of the upper mixed layer associated with the impact of mesoscale eddies is poorly studied. The 45-year historical data set was retrieved, in order to select the bathy-photometric surveys carried out in the form of station grids and transects across eddies.

View Article and Find Full Text PDF

With growing awareness that what we put in and on our bodies affects our health and wellbeing, little is still known about the impact of textiles on the human skin. Athletic wear often uses silver threading to improve hygiene, but little is known about its effect on the body's largest organ. In this study, we investigated the impact of such clothing on the skin's chemistry and microbiome.

View Article and Find Full Text PDF

A review of the literature on the problem of the use of non-invasive technologies in early diagnosis and prediction of age-associated cognitive decline associated with Alzheimer's disease is presented. The main attention is paid to the study of the buccal epithelium, oral fluid, as surrogate models of degenerative lesions of cerebral structures, as well as determining the role of oral microorganisms in the formation and development of cognitive disorders. An original hypothesis of neurodegenerative lesions of cerebral structures is presented, on the basis of which an algorithm for studying the state of the oral cavity is proposed in order to detect and predict cognitive deficits as early as possible.

View Article and Find Full Text PDF

In January 2022, during scientific cruise 87 on the RV Academic Mstislav Keldysh in the Atlantic sector of the Southern Ocean, three hydrobiophysical cross-sections were performed in the Bransfield Strait. Bioluminescent signals were measured in a layer of 0-200 m at each of the 24 stations located at three sites. For the first time, a new hydrobiological system 'Salpa MA +' was used, which made it possible to obtain novel data in the photic layer of the studied water area.

View Article and Find Full Text PDF

The chemistry of indoor surfaces and the role of microbes in shaping and responding to that chemistry are largely unexplored. We found that, over 1 month, people's presence and activities profoundly reshaped the chemistry of a house. Molecules associated with eating/cooking, bathroom use, and personal care were found throughout the entire house, while molecules associated with medications, outdoor biocides, and microbially derived compounds were distributed in a location-dependent manner.

View Article and Find Full Text PDF

Large-scale surveys represented by 5800 bathymetric casts in the western Indian Ocean (0-22 N, 54-58 E), elucidated the 10-fold variation of the bioluminescent potential (BP) in the upper mixed layer, during the winter (north-east) monsoon season. The mesoscale survey in February 2017 consisted of 26 drift stations (4 N-3 S, 65-68 E) on which 5-10 bathymetric casts were deployed down to 60 m. The maximal BP was associated with the periphery of a cyclonic eddy.

View Article and Find Full Text PDF
Article Synopsis
  • Understanding the microbial and chemical diversity in traditional fermented foods like Chinese dark teas (CDTs) is crucial for modern manufacturing.
  • Research using microbial DNA sequencing and mass spectrometry identified key influences on CDT diversity, primarily geography (latitude) and manufacturing methods (pile fermentation).
  • The study found many metabolites shared between CDTs and fungi, highlighting compounds important for taste and nutrition, while also revealing patterns in chemical families through molecular networking.
View Article and Find Full Text PDF

The toolbox available for microbiologists to study interspecies interactions is rapidly growing, and with continuously more advanced instruments, we are able to expand our knowledge on establishment and function of microbial communities. However, unravelling molecular interspecies interactions in complex biological systems remains a challenge, and interactions are therefore often studied in simplified communities. Here we perform an in-depth characterization of an observed interspecies interaction between two co-isolated bacteria, and .

View Article and Find Full Text PDF

Not all infants carry specialized gut microbes, meaning they cannot digest human milk oligosaccharides and therefore do not receive complete benefits from human milk. EVC001 is equipped to convert the full array of complex oligosaccharides into compounds usable by the infant, making it an ideal candidate to stabilize gut function and improve nutrition in preterm infants. A prospective, open-label study design was used to evaluate the tolerability of EVC001 and its effects on the fecal microbiota in preterm infants in a Neonatal Intensive Care Unit.

View Article and Find Full Text PDF

The leaf homogenate of is widely used in Samoan traditional medicine to treat inflammation associated with fever, body aches, swellings, wounds, elephantiasis, incontinence, skin infections, vomiting, respiratory infections, and abdominal distress. However, the bioactive components and underlying mechanisms of action are unknown. We used chemical genomic analyses in the model organism (baker's yeast) to identify and characterize an iron homeostasis mechanism of action in the traditional medicine as an unfractionated entity to emulate its traditional use.

View Article and Find Full Text PDF

Decentralization is a central characteristic of biological motor control that allows for fast responses relying on local sensory information. In contrast, the current trend of Deep Reinforcement Learning (DRL) based approaches to motor control follows a centralized paradigm using a single, holistic controller that has to untangle the whole input information space. This motivates to ask whether decentralization as seen in biological control architectures might also be beneficial for embodied sensori-motor control systems when using DRL.

View Article and Find Full Text PDF

In this work, IBSS materials on seawater bioluminescence intensity changes in the Atlantic sector of the Antarctic Ocean (the Weddell Sea area) with an interval of almost 20 years are presented. Data were obtained using a single instrument, the hydrobiophysical system Salpa-M, in the area of 50-63°S, 62-49°W in March 2002 (183 soundings at 45 stations during cruise 7 on RV Gorizont) and in February 2020 (122 soundings at 18 stations during cruise 79 on RV Academic Mstislav Keldysh). The bioluminescence studies were coupled with the simultaneous measurement of temperature, electrical conductivity, and photosynthetically active radiation, and they were compared with the data from processing plankton samples.

View Article and Find Full Text PDF

Deep Reinforcement Learning techniques demonstrate advances in the domain of robotics. One of the limiting factors is a large number of interaction samples usually required for training in simulated and real-world environments. In this work, we demonstrate for a set of simulated dexterous in-hand object manipulation tasks that tactile information can substantially increase sample efficiency for training (by up to more than threefold).

View Article and Find Full Text PDF

Vertical distribution of ctenophores near the boundary of oxygen-depleted waters of the Black Sea redoxcline was studied by use of video observations with real-time water sampling, horizontal MultiNet towing, and soundings using bathyphotometers with simultaneous vertical plankton net sampling. The results of the study showed for the first time that the daytime accumulation of ctenophores above the upper boundary of the suboxic zone changes the biophysical properties of the medium, causing an increase in the daytime intensity of bioluminescence near the redoxcline. The dynamics of this glow is in antiphase to that in the surface layers, where it is associated with the bioluminescence of phytoplankton.

View Article and Find Full Text PDF

Bench tests of a 15 keV helium ion source, which has been developed for the neutral particle diagnostic system of the International Thermonuclear Experimental Reactor (ITER), are described. Being part of the diagnostic system, the ion source will be used to monitor the intactness of carbon stripping foils as well as to check the detection and dispersion systems of the main diagnostic instruments-neutral particle analyzers (NPAs). The ion source produces a wide 5-cm diameter (FWHM) ion beam at a distance of about 50 cm; the ion beam uniformity at a 2-cm area corresponding to the size of the stripping foil is not worse than 10%.

View Article and Find Full Text PDF