Environmental Conditions Research Articles

Differential absorption laser spectroscopy at 8 kHz using precompensated current modulation

We present a differential laser absorption spectroscopy (DLAS) system operating at 1550 nm for rapid and sensitive gas concentration measurements. A dual-wavelength toggling mechanism is presented, which significantly reduces data processing, hence supporting a high update rate and data robustness against fast-changing environmental conditions. We showcase the ability to toggle between two wavelengths separated by 90 pm in 14 μs and with minimal chirp (∼1 pm), facilitating sensitive DLAS measurements at 8 kHz update rate. This performance is achieved by driving a 1550 nm diode laser with a modified square-wave current pulse, overcoming the thermal time constant limited wavelength-modulation response of the diode laser. A sensitive feedback mechanism ensures excellent long-term wavelength stability better than 1.4 pm peak-to-peak at 8 kHz toggling over 20 h. As a performance test, we measured the volumetric ratio (VMR) of hydrogen cyanide (HCN) gas in a fiber-coupled gas cell with less than 0.2% peak-to-peak variation over 20 h at 40 Hz. A best sensitivity in VMR of 8×10−6 was achieved at 25 ms integration time. The simplicity and high update rate of our system make it well-suited for gas monitoring in dynamic atmospheric and industrial environments. Further, it offers potential utility in applications requiring precise wavelength control, such as injection seeding of pulsed lasers. A simple analytical model is derived, which, in detail, supports the experimental results, hence offering a tool for future design optimization.

Germplasm collection and ex situ conservation of Adansonia digitata in Ghana

ABSTRACT Baobab (Adansonia digitata L.) domestication and conservation have become necessary due to its increasing global usage and decreasing population. Although it is resilient and survives harsh environmental conditions, its destruction due to anthropogenic and natural forces could lead to genetic erosion. Therefore, it is important to domesticate the baobab and provide it with the necessary husbandry practices to ensure its survival. The objective of the study was to collect baobab germplasm across the Volta Region of Ghana for conservation. A reconnaissance survey was conducted and followed with germplasm collection. As a result, 109 accessions were collected within latitude 5°47ʹ46.24190ʹʹ to 7° 9ʹ34.15030ʹʹN and longitude 0°11ʹ35.25ʹʹto1°8ʹ36.74180 ʹʹE. They were from mangrove swamps, woodland savannah, grassland savannah and deciduous forest. The scions were grafted on pre-raised rootstocks. They are represented on a bar chart, and a three-dimensional map drawn indicating the geographic locations of collection. The lowest and highest altitudes at the ground at which the accessions were taken were 4 m and 287 m, respectively. The accessions were planted in the Ho Technical University ex situ gene bank. The collection will help in the maintenance of baobab genetic diversity, serve as materials for studies and crop improvement, and improve biodiversity.

Investigating and Evaluating Novel Fly Ash-Based Proppant Compressive Strength Under Various Environmental Conditions

As hydraulic fracturing becomes increasingly prevalent in the oil and gas industry, there is a growing need to develop more cost-effective and sustainable technologies, particularly concerning the materials used. Proppants play a vital role in hydraulic fracturing by ensuring that fractures remain conductive and can withstand the pressure exerted by the surrounding strata. One key parameter for evaluating proppants is their compressive strength, especially under harsh environmental conditions. High-strength proppants, such as those made from ceramics or bauxite, are typically expensive due to the materials and complex manufacturing processes involved. In contrast, fly ash, a byproduct of coal-fired power plants, offers a more affordable and environmentally sustainable alternative for proppant production. This study focuses on the development and evaluation of a fly ash-based proppant, exposed to harsh conditions including high temperature and pressure, as well as acidic, alkaline, saline, and crude oil environments. The fly ash was activated using an alkaline solution, which served as a chemical binder for the proppant. After exposure to these conditions, the compressive strength of the fly ash-based proppants was compared to control samples. The results showed that the proppants’ compressive strength was largely unaffected by the harsh environments, particularly for the B20W25 mix design. However, while the fly ash-based proppants performed well under stress, their compressive strength was still lower than that of conventional proppants used in the industry. The B20W25 sample demonstrated a compressive strength of 1181.19 psi (8.1 MPa), which, although resilient, remains below industry standards.

Investigation of Exome-Wide Tumor Heterogeneity on Colorectal Tissue-Based Single Cells

The progression of colorectal cancer is strongly influenced by environmental and genetic conditions. One of the key factors is tumor heterogeneity which is extensively studied by cfDNA and bulk sequencing methods; however, we lack knowledge regarding its effects at the single-cell level. Motivated by this, we aimed to employ an end-to-end single-cell sequencing workflow from tissue-derived sample isolation to exome sequencing. Our main goal was to investigate the heterogeneity patterns by laser microdissecting samples from different locations of a tissue slide. Moreover, by studying healthy colon control, tumor-associated normal, and colorectal cancer tissues, we explored tissue-specific heterogeneity motifs. For completeness, we also compared the performance of the whole-exome bulk, cfDNA, and single-cell sequencing methods based on variation at the level of a single nucleotide.

How do red foxes (Vulpes vulpes) explore their environment? Characteristics of movement patterns in time and space

Abstract Background Many animals must adapt their movements to different conditions encountered during different life phases, such as when exploring extraterritorial areas for dispersal, foraging or breeding. To better understand how animals move in different movement phases, we asked whether movement patterns differ between one way directed movements, such as during the transient phase of dispersal or two way exploratory-like movements such as during extraterritorial excursions or stationary movements. Methods We GPS collared red foxes in a rural area in southern Germany between 2020 and 2023. Using a random forest model, we analyzed different movement parameters, habitat features—for example landclasses and distances to linear structures—and time variables (season and time of day) within red fox exploratory, transient and stationary movement phases to characterize phase specific movement patterns and to investigate the influence of different variables on classifying the movement phases. Results According to the classification model, the movement patterns in the different phases were characterized most strongly by the variables persistence velocity, season, step length and distance to linear structures. In extraterritorial areas, red foxes either moved straight with high persistence velocity, close to anthropogenic linear structures during transient movements, or more tortuously containing a higher variance in turning angles and a decrease in persistence velocity during exploratory-like movements. Transient movements mainly took place during autumn, whereas exploratory-like movements were mainly conducted during winter and spring. Conclusion Movement patterns of red foxes differ between transient, exploratory and stationary phases, reflecting displacement, searching and resident movement strategies. Our results signify the importance of the combined effect of using movement, habitat and time variables together in analyzing movement phases. High movement variability may allow red foxes to navigate in extraterritorial areas efficiently and to adapt to different environmental and behavioral conditions.

Regulation of Flavonoid Biosynthesis by the MYB-bHLH-WDR (MBW) Complex in Plants and Its Specific Features in Cereals

Flavonoids are a large group of secondary metabolites, which are responsible for pigmentation, signaling, protection from unfavorable environmental conditions, and other important functions, as well as providing numerous benefits for human health. Various stages of flavonoid biosynthesis are subject to complex regulation by three groups of transcription regulators—MYC-like bHLH, R2R3-MYB and WDR which form the MBW regulatory complex. We attempt to cover the main aspects of this intriguing regulatory system in plants, as well as to summarize information on their distinctive features in cereals. Published data revealed the following perspectives for further research: (1) In cereals, a large number of paralogs of MYC and MYB transcription factors are present, and their diversification has led to spatial and biochemical specialization, providing an opportunity to fine-tune the distribution and composition of flavonoid compounds; (2) Regulatory systems formed by MBW proteins in cereals possess distinctive features that are not yet fully understood and require further investigation; (3) Non-classical MB-EMSY-like complexes, WDR-independent MB complexes, and solely acting R2R3-MYB transcription factors are of particular interest for studying unique regulatory mechanisms in plants. More comprehensive understanding of flavonoid biosynthesis regulation will allow us to develop cereal varieties with the required flavonoid content and spatial distribution.

Tourism Industry in Vietnam: Importance for the Economy and Development Challenges

The article discusses the prospects for the development of the tourism industry in Vietnam, as well as cooperation in this area with Russia. Environmental conditions determine the tourist attractiveness of the country and great opportunities for beach recreation. Tourism is an important part of the modern Vietnamese economy. The author examines successes and difficulties of developing this industry in Vietnam.

Punctuated versus gradual shifts in the multivariate evolutionary process: a test with paired radiations of scincid lizards

Abstract As lineages become separated in time, they are expected to accumulate mutational (or developmental-genetic) differences that influence the macroevolutionary trajectories of those lineages even under similar environmental conditions. Here, we compare the dynamics of phenotypic evolution in radiations of scincid lizards from Australia and Madagascar that are separated by more than 100 million years of independent evolution and show rampant phenotypic parallelism. We collected linear measurements of the skull, limbs, and limb girdles from micro-CT scans of 94 Australian and 29 Malagasy species. Using multivariate comparative methods, we tested whether the underlying evolutionary covariance structure for this superficial parallelism was conserved and whether these patterns were consistent across distinct functional modules. Malagasy and most Australian skinks have similar covariance matrices for skull evolution. Results are ambiguous for limbs and limb girdles, as some trait subsets support different evolutionary processes and for other subsets, a shared covariance matrix could not be rejected. However, across most trait sets, the extremely speciose Australian genus Ctenotus exhibits a radically different covariance structure from all other lizards in these groups, including several closely related genera. The shift in Ctenotus demonstrates that the architecture of trait correlations can change at relatively shallow timescales and may explain the unique position of this clade in morphospace relative to other scincid lizards from both geographic regions. More generally, our results demonstrate that the multivariate evolutionary process can change dramatically in a relatively short period of time.

Tropical fruit-derived Lactiplantibacillus as potential probiotic and antifungal agents against Fusarium oxysporum

Abstract Fifty-five lactic acid bacteria (LAB) were isolated from seven selected tropical fruits, with Solanum nigrum exhibiting the highest LAB prevalence and Couroupita guianenis and Musa fruits showing the lowest counts. Two strains isolated from Ficus racemosa demonstrated significant antifungal activity against Fusarium oxysporum. 16S rDNA sequencing identified these strains as Lactiplantibacillus plantarum MYSVCF3 and Lpb. argentoratensis MYSVCF5. The isolates displayed adaptability to a broad range of environmental conditions, including temperatures of 10–45 °C, pH 2–6, and salt up to 7%. The strains tolerated simulated gastrointestinal conditions of acid (pH-2), phenol (0.6%), and bile (0.3%) suggesting potential probiotic attributes. Lpb. argentoratensis MYSVCF5 inhibited F. oxysporum, two ESKAPE group bacteria (P. aeruginosa, S. aureus) plus S. paratyphi and E. coli. The cell-free supernatant (CFS) of Lpb. argentoratensis MYSVCF5 reduced the growth of fungal biomass by 94% and completely inhibited conidial germination, retaining activity even after extended cold storage. LC–MS/MS analysis identified organic acids in the CFS, with citric acid as the most abundant at 34.9 (± 0.3) µg/mL, followed by lactic (8.3 µg/mL) and malic acids (5.2 µg/mL). This study isolated a novel LAB, a potential candidate having probiotics and antifungal properties for application in food and agriculture.

Advanced Path Planning for UAV Swarms in Smart City Disaster Scenarios Using Hybrid Metaheuristic Algorithms

In disaster-stricken areas, rapid restoration of communication infrastructure is critical to ensuring effective emergency response and recovery. Swarm UAVs, operating as mobile aerial base stations (MABS), offer a transformative solution for bridging connectivity gaps in environments where the traditional infrastructure has been compromised. This paper presents a novel hybrid path planning approach combining affinity propagation clustering (APC) with genetic algorithms (GA), aimed at maximizing coverage, and ensuring quality of service (QoS) compliance across diverse environmental conditions. Comprehensive simulations conducted in suburban, urban, dense urban, and high-rise urban environments demonstrated the efficacy of the APC-GA approach. The proposed method achieved up to 100% coverage in suburban settings with only eight unmanned aerial vehicle (UAV) swarms, and maintained superior performance in dense and high-rise urban environments, achieving 97% and 93% coverage, respectively, with 10 UAV swarms. The QoS compliance reached 98%, outperforming benchmarks such as GA (94%), PSO (90%), and ACO (88%). The solution exhibited significant stability, maintaining consistently high performance, highlighting its robustness under dynamic disaster scenarios. Mobility model analysis further underscores the adaptability of the proposed approach. The reference point group mobility (RPGM) model consistently achieved higher coverage rates (95%) than the random waypoint model (RWPM) (90%), thereby demonstrating the importance of group-based mobility patterns in enhancing UAV deployment efficiency. The findings reveal that the APC-GA adaptive clustering and path planning mechanisms effectively navigate propagation challenges, interference, and non-line-of-sight (NLOS) conditions, ensuring reliable connectivity in the most demanding environments. This research establishes the APC-GA hybrid as a scalable and QoS-compliant solution for UAV deployment in disaster response scenarios. By dynamically adapting to environmental complexities and user mobility patterns, it advances state-of-the-art emergency communication systems, offering a robust framework for real-world applications in disaster resilience and recovery.

Biofilm Formation, Modulation, and Transcriptomic Regulation Under Stress Conditions in Halomicronema sp.

In nature, bacteria often form heterogeneous communities enclosed in a complex matrix known as biofilms. This extracellular matrix, produced by the microorganisms themselves, serves as the first barrier between the cells and the environment. It is composed mainly of water, extracellular polymeric substances (EPS), lipids, proteins, and DNA. Cyanobacteria form biofilms and have unique characteristics such as oxygenic photosynthesis, nitrogen fixation, excellent adaptability to various abiotic stress conditions, and the ability to secrete a variety of metabolites and hormones. This work focused on the characterization of the cyanobacterium Halomicronema sp. strain isolated from a brackish environment. This study included microscopic imaging, determination of phenolic content and antioxidant capacity, identification of chemicals interfering with biofilm formation, and transcriptomic analysis by RNA sequencing and real-time PCR. Gene expression analysis was centered on genes related to the production of EPS and biofilm-related transcription factors. This study led to the identification of wza1 and wzt as EPS biomarkers and luxR-05665, along with genes belonging to the TetR/AcrR and LysR families, as potential biomarkers useful for studying and monitoring biofilm formation under different environmental conditions. Moreover, this work revealed that Halomicronema sp. can grow even in the presence of strong abiotic stresses, such as high salt, and has good antioxidant properties.

Occurrence of Pestalotiopsis sp. on Ornamental Plants Camellia japonica L. in Romanian Public Gardens

Camellias are evergreen shrubs native to the eastern and southern regions of Asia. In Romania, camellias are popular ornamental plants grown in pots. Pestalotiopsis species have a worldwide distribution and are pathogenic to a wide range of hosts. They also represent an important group of endophytes capable of producing a variety of bioactive secondary metabolites. This paper reports the occurrence of grey blight and twig or branch dieback caused by Pestalotiopsis sp. on Camellia japonica L. grown in pots and used in the landscaping of a public garden located in Iasi city, Romania (GPS coordinates: 47°09′24.0″ N 27°35′15.6″ E). Pestalotiopsis species were identified based on morphological characteristics and Sanger sequencing. Genomic analysis of the fungal isolate coded P_CJ_24, obtained from living plants, was based on ribosomal internal transcribed spacer region amplification using the LSU primers. This first report of Pestalotiopsis species infection of ornamental plants in Romania suggests that new plant pathogens can be introduced in new environmental conditions through plant pods and their incidence increases with the widespread of plant material among gardens.

Changes in enzymatic activity and oxidative stress in honeybees kept in the apiary and laboratory conditions during the course of nosemosis

The aim of this study was to investigate the changes in the level of oxidative stress and lysozyme-like and phenoloxidase (PO) activity under the influence of nosemosis. Honeybees were kept in natural (apiary) and artificial (laboratory) conditions. In this study, it was shown for the first time that honeybees kept in apiaries have higher levels and activity of the studied parameters than honeybees kept in the laboratory. The greatest difference was noted in the case of PO activity in 28-day-old infected honeybees in May, when the activity was 32.3 times higher in honeybees kept in the apiary than in the laboratory, suggesting that environmental conditions have a significant influence on the immune response of honeybees. Simultaneously, the apiary conditions resulted in higher level of oxidative stress, indicating lower effectiveness of antioxidative mechanisms. Additional nosemosis infection increased the level of oxidative stress as well as lysozyme and PO activities. In July, in 28-day-old infected honeybees kept in laboratory, the highest increase in PO activity (by 10.79 fold) was detected compared to healthy honeybees. This may indicate that infection causes a decrease in the effectiveness of primarily antioxidant mechanisms, whereas immune mechanisms are still activated during infection. Another interesting factor is the age of the honeybees. It was found that in the summer months (June, July) the lysozyme-like and PO activities increased with age, while in the case of oxidative stress the opposite trend was observed, suggesting better effectiveness of both immune and antioxidant mechanisms. Another important element is seasonality, which significantly affected only the lysozyme-like activity. It was found that in July in all the groups studied this activity was higher than in the other months. The results allow us to better understand the mechanisms of honeybee immunity, which are constantly being studied due to the complex social structure created by these insects. Our research emphasizes that honeybee immunity is dynamic and depends on a number of factors, such as environment, age, season or the presence of pathogens.

Causes of Mortality in Harbor (Phoca vitulina) and Gray (Halichoerus grypus) Seals in Denmark

Determination of the causes of mortality in stranded marine mammals can contribute valuable information for conservation of wild populations, as well as contribute to risk assessments for different pathogens, hosts, and environmental conditions. This study examined necropsy reports for harbor (Phoca vitulina; n = 213) and gray (Halichoerus grypus; n = 40) seals stranded in Denmark in the period 2014 to 2021 to determine the causes of mortality where feasible. The likelihood that human interactions did or might have contributed to the mortality was also assessed. Infection with lungworms, heartworms, gastrointestinal roundworms, and influenza virus was tested for each seal in the data. Parasitic bronchopneumonia was the most common cause of death in both harbor (n = 68) and gray (n = 8) seals, and significantly more juveniles than adults died as a result of parasitic infections in the harbor seal cohort. Starvation was also a major cause of death in juvenile seals. Cause of death, death class (found dead, euthanized, or culled), and whether human interactions played a role in mortality did not vary significantly between the two species. Traumatic causes of death, resulting from confirmed or probable human interactions, were associated with adult and subadult seals of both species. Culling was the cause of death for 13.6% of harbor seals and 17.5% of gray seals.

A Study on the Standardization of Smart Farm Communication

Background: Smart farming uses information and communication technology (ICT) to optimize crop and livestock environments. It is applied in greenhouses, vinyl houses, and livestock barns. By collecting data on crop growth and environmental conditions, smart farms create optimal growth environments. This leads to higher productivity and better quality with less labor, energy, and nutrient input than traditional farming methods. In Korea, crop production has declined due to fewer farmers, and over 80% of agricultural products are imported. The low birth rate and aging population are worsening the shortage of agricultural workers. It is predicted that Korea could face a food shortage in three years due to low self-sufficiency. Smart farms are seen as a solution. They can be implemented in urban areas and are considered a profitable model due to their high production potential. Methods: Nutrient machines are a vital part of smart farming. They dilute and supply essential nutrients for crop growth. However, different machines require varying nutrient ratios, which complicates crop management. To address this, a recipe program has been developed. It automatically adjusts nutrient ratios according to the user’s standard settings. This ensures uniform nutrient delivery, regardless of the type of machine used. Result: The recipe program is expected to improve crop production. It ensures consistent nutrient supply, optimizing growth conditions. It also enhances user convenience by standardizing nutrient management across different machines, reducing complexity in crop cultivation.

Patterns of interpopulation variation and physiological trade-offs of the acute thermal tolerance of juvenile Chinook salmon (Oncorhynchus tshawytscha)

IntroductionThe capacity of species and populations to respond to rapid environmental change will be pivotal for their resilience in the coming decades. To explore thermal plasticity, physiological trade-offs, and associations with environmental characteristics, we assessed the heat hardening response and acclimation capacity of juvenile Chinook salmon (Oncorhynchus tshawytscha) from seven hatchery populations spanning diverse ecoregions along the West Coast of the United States.MethodsProgeny from each population were acclimated to one of three temperatures (11, 16, or 20°C) and subjected to two acute thermal maximum (CTMAX) trials 24 h apart. The heat hardening response (ΔCTM) was calculated as the difference between an individual's second and first CTMAX trials. Acclimation capacity was determined as the maximum difference in CTMAX between fish acclimated to 11°C and 20°C during their second trial, capturing the full acclimatory scope. Bayesian models were employed to test the thermal trade-off hypothesis, which posits that individuals or populations with higher thermal tolerance have reduced capacity for acclimation. Trade-offs were analyzed at both individual and population scales. Associations between ΔCTM, acclimation capacity, and source population environmental characteristics were also examined using data from a landscape-scale, regional, river temperature model.ResultsFish acclimated to 16°C or 20°C exhibited heat hardening (positive ΔCTM), while those acclimated to 11°C exhibited “heat weakening” (negative ΔCTM), a rare phenomenon in the literature. At the individual level, fish adhered to the thermal trade-off hypothesis, with higher thermal tolerance associated with reduced plasticity. However, no such trade-off was observed at the population level. Acclimation capacity was positively correlated with latitude and the temperature of the natural rearing environment. Additionally, ΔCTM performance improved when fish were acclimated to temperatures closer to those of their natural habitats.DiscussionIndividual fish exhibited a trade-off between thermal tolerance and plasticity, while populations did not. Thermal plasticity was associated with environmental conditions, with populations from warmer habitats demonstrating greater acclimation and heat hardening capacities. This study highlights the importance of understanding interpopulation variation to identify at-risk populations, such as those from colder habitats or with limited thermal plasticity, like the Trinity population. These findings emphasize the need to account for interpopulation differences when predicting species responses to climate change and developing conservation strategies.

Effects of Providing Enrichment to Broilers in an Animal Welfare Environment on Productivity, Litter Moisture, Gas Concentration (CO2 and NH3), Animal Welfare Indicators, and Stress Level Concentration

As animal welfare becomes more active in livestock industry, research is being conducted on ways to improve poor housing environments, reduce stress, and meet welfare standards. Among these, environmental enrichment methods are effective in reducing stress and creating a welfare-friendly rearing environment, but there are few cases of actual application to farms. Therefore, we aimed to investigate the effect of providing pecking materials (grain blocks), known as one of the environmental enrichment methods, to commercial broiler farms. This study used two facilities that could accommodate 32,000 one-day-old broilers (Arbor acres) per building, and two groups (control and treatment groups) were designed after creating two identical areas within each building (total two treatments, two replicates, 16,000 birds per replicate). Two identical zones within the house were created by installing a partition in the center; one side was provided with grain blocks (one grain block per 1000 birds), and the other side was not. Analysis items included productivity (body weight, uniformity), environmental variables (litter and air), welfare indicators (leg, gait score, feather cleanliness score), and serum corticosterone levels. Analysis of all items was conducted twice, on the 19th and 27th, taking into account the farm’s feed change date and slaughter schedule. Other environmental conditions (density, lighting, ventilation, temperature, humidity, feed, and water) were the same. As a result, no difference in productivity was observed according to enrichment, and the quality of litter and air was similar. Also, there was no significant difference in welfare indicators. Interestingly, however, provision of the environment enrichment lowered serum corticosterone levels (p < 0.05). The implications of our study are that grain blocks as a pecking material are an effective way to reduce stress without adversely affecting broiler performance and rearing environment. However, it is still necessary to explore optimal enrichment materials that can help not only the welfare level but also the broiler performance.

Climate change impact on the viability of western sand lance during estivation in the Seto Inland Sea

Abstract The western sand lance (Ammodytes japonicus) is a valuable fishery resource in the Seto Inland Sea. Although it survives through summer by estivating, it faces the threat of population decline as seawater temperature increases at an alarming rate due to climate change. We applied data from meta-analyses and laboratory analyses to inform a climate-linked model of predicted survival to determine the impact of climate change on the persistence of A. japonicus through the end of the century. Our results suggest that the mortality rate of A. japonicus during estivation increases with elevated water temperature, and the initial condition factor at the onset of estivation is critical to the survival of estivating A. japonicus. Furthermore, our results indicate that climate change will pose serious challenges to the persistence of the A. japonicus population in the Seto Inland Sea in the twenty-first century if climate change mitigation measures are not implemented and the environmental conditions that promote accumulation of energy reserves in A. japonicus prior to estivation are not improved.

Influence of the Applied WC/C and CrN + WC/C Coatings on the Surface Protection of X2CrNi18-9 Cavitation Generators

The purpose of this paper is to investigate the impact of the applied WC/C and CrN + WC/C protective coatings applied using various PVD methods as protection for cavitation generators operating in an environment of intense cavitation wear. In order to carry out planned tasks, special devices generating a cavitation environment have been designed and manufactured. As part of this study, an analysis of the surface of cavitation generators, both before applying the coatings and with the applied protective PVD coatings, and also before and after operation in a cavitation environment, was carried out using the following research techniques: stereoscopic microscopy, scanning electron microscopy, transmission microscopy, XRD, and confocal microscopy. Despite the use of corrosion-resistant steels as a result of the cavitation environment, this causes surface material wear, especially in the area of the through holes. This is due to the fact that there are no protective coatings inside the through hole. Moreover, it was found that, for the tested steel with multilayer CrN + WC/C coatings, there were significantly fewer cavitation defects both on the surface of the material and on the edge of through holes, which indicates that the use of these multilayer coatings can significantly extend the service life of structural elements operating in such environmental conditions. Based on the conducted research tests, it was proven that the applying protective coatings significantly reduce the wear of the surfaces of the tested cavitation generators, thus allowing the use of cheaper steels, not resistant to corrosion, e.g., P265GH steel, which is five times cheaper than austenitic steel. The P265GH steel is used for structural elements in the heating, petrochemical, energy, food, and chemical industries, as well as for structural elements in the aviation, shipbuilding, and many other industries, and, thus, it is possible to reduce the costs associated with the operation of this construction solution in industrial conditions.

Polydiacetylene (PDA) Embedded Polymer-Based Network Structure for Biosensor Applications

Biosensors, which combine physical transducers with biorecognition elements, have seen significant advancement due to the heightened interest in rapid diagnostic technologies across a number of fields, including medical diagnostics, environmental monitoring, and food safety. In particular, polydiacetylene (PDA) is gaining attention as an ideal material for label-free colorimetric biosensor development due to its unique color-changing properties in response to external stimuli. PDA forms through the self-assembly of diacetylene monomers, with color change occurring as its conjugated backbone twists in response to stimuli such as temperature, pH, and chemical interactions. This color change enables the detection of biomarkers, metal ions, and toxic compounds. Moreover, the combination of PDA with polymeric structures including hydrogels further enhances the sensitivity and structural stability of PDA-based biosensors, making them reliable and effective in complex biological and environmental conditions. This review comprehensively examines recent research trends and applications of PDA–polymeric structure hybrid biosensors, while discussing future directions and potential advancements in this field.