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As biocatalytic strategies for PET recycling reach maturation, insights gained from PET hydrolase research can be leveraged to inform the design of proteins and surface-functionalization strategies that promote stable association of functional proteins with PET surfaces, enabling the development of functional protein-plastic hybrid materials. Herein, we examine recent developments in biofunctionalization strategies of PET and related materials, with a focus on chemical biology approaches that offer more precise control of the orientation of proteins on PET and related materials. Biophysical insights from protein-polymer interface chemistry studies can inform protein selection, design, and engineering approaches to minimize denaturation and maximize function of proteins upon attachment to surfaces. Finally, we highlight applications of protein-functionalized PET and related synthetic polymers, including for biomedical applications and scalable biocatalysis, showcasing the potential of integrating biological activity into durable synthetic polymers.

Background and objectives Timely transport of donor organs is a critical determinant of successful transplantation because organ viability is limited by cold ischaemic time (CIT). Unmanned aerial vehicles (UAVs), commonly referred to as drones, have recently emerged as promising tools for rapid medical logistics. The present study describes the design, engineering validation, and field evaluation of a drone-compatible organ transport container capable of maintaining cold-chain conditions during aerial transport. Methods A multidisciplinary engineering framework integrating biomedical engineering, materials science and transplant logistics consultation was used to design a lightweight crash-resistant container. The system incorporates carbon fibre reinforced polymer (CFRP) with aluminium reinforcement for structural stability, phase change materials (PCMs) for passive thermal regulation, and embedded sensors for monitoring temperature and mechanical shocks. Structural simulations, laboratory drop tests, thermal stability experiments, and pilot drone flight trials were conducted to evaluate mechanical resilience and preservation performance. Results Finite element simulations demonstrated that the composite container could withstand anticipated operational loads with adequate safety margins. Drop tests from heights up to 18.3 m resulted in minimal structural deformation while the internal payload chamber remained protected. Thermal experiments confirmed that PCM-based cooling maintained preservation temperatures within 0-4 °C for more than 18 h. Drone flight trials using a hexacopter UAV confirmed stable payload handling and maintenance of cold-chain conditions during simulated transport. Interpretation and conclusions The prototype demonstrates proof-of-concept feasibility for drone-compatible organ transport. UAV-enabled logistics may complement existing organ transport systems by reducing delays associated with traffic congestion and coordination challenges. Further clinical validation and regulatory approvals are required before routine deployment.

Salinity is a major constraint on maize establishment, yet the extent of early-stage variation among native Mexican maize accessions remains insufficiently characterized. This study evaluated the in vitro response of 130 native maize accessions (Zea mays L.) to saline stress in order to identify promising materials for early-stage salinity tolerance. Seeds were germinated under control and saline conditions (150 mM NaCl), and early seedling traits were recorded, including germination, coleoptile length, mesocotyl length, radicle length, seminal root number, and seedling biomass. Univariate analyses were used to identify contrasting accession responses, whereas principal component analysis, Ward's hierarchical clustering, and optimized stratification were applied to classify phenotypic patterns under saline stress. Salinity reduced germination and early seedling growth overall, but the magnitude of these effects varied markedly among accessions, revealing substantial phenotypic variation at the earliest developmental stages. Several accessions maintained favourable performance under saline stress. In particular, CIMMYT 433 combined stable germination with superior radicle length and seminal root number, whereas CIMMYT 658 showed favourable coleoptile and mesocotyl elongation. Multivariate analysis based on accession-specific NaCl-response differences identified four contrasting response groups. Cluster 1 showed the lowest overall NaCl-induced reduction and therefore grouped accessions with greater early-stage stability, whereas Cluster 2 showed the greatest reductions and represented the most affected response group. Tuxpeño and Olotillo related materials were prominent among the accessions with favourable early-stage responses. Native Mexican maize harbours substantial early-stage variation in response to salinity, and this variation can be effectively captured through integrated seedling traits and multivariate classification. The accessions identified here represent promising germplasm for further physiological, genetic, and breeding studies aimed at improving salinity tolerance.

Materials with ultralow thermal conductivities are highly desirable for thermal management to capture the enormous amount of waste heat required to generate electricity. In this paper, using first-principles simulations, we investigate the intrinsic phonon transport characteristics of three sp2-hybrid carbon sheets. At room temperature, the lattice thermal conductivity of hybrid Kagome graphene and Kagome graphene is about 445 W m-1 K-1 and 42 W m-1 K-1, which are merely 5.8% and 1.5% that of graphene, respectively. We attribute these distinct properties to the obvious flat phonon bands in the phonon spectra of the Kagome structure owing to the intrinsic localized vibration ring. To further understand the suppression of the thermal conductivity in the Kagome lattice, we decompose the phonon mode properties. It is found that the low group velocity caused by the flat band and the strong anharmonicity caused by the lattice distortion of the Kagome lattice are the main origins of the obvious suppression of thermal conductivity. The results presented in this work shed light on the lattice thermal conductivity of graphene allotropes with a Kagome lattice and provide a viable way to modulate the thermal conductivity of 2D materials.

The electricity-free conversion of polymer waste into high-value functional materials represents an important step toward sustainable and circular manufacturing. Herein, we demonstrate a light-driven upcycling platform that directly transforms vulcanized waste tires into electrocatalyst supports for proton exchange membrane fuel cells (PEMFCs). In this process, waste tires form uniform composites with effective light absorbers such as MoS2 nanosheets, enabling near-infrared (NIR) light or natural sunlight to be converted into localized high-temperature thermal fields. By investigating the fundamental correlation between composite design, microstructure, and carbonization efficiency, we show that waste tires are turned into effective Pt catalyst supports via NIR- and sunlight-driven carbonization. The resulting PEMFCs deliver a maximum power density of 982 mW cm-2 (NIR) and 1048 mW cm-2 (natural sunlight), respectively, under H2/O2 operation, which are comparable to that of a benchmark Pt/C device (1024 mW cm-2). These results demonstrate that the light-driven carbonization enables the production of carbon supports with sufficient conductivity, Pt accessibility, and catalyst-layer compatibility for fuel-cell operation. Additionally, sunlight-based photothermal carbonization is accomplished in less than 1 min under ambient conditions, highlighting its potential as an alternative to conventional, energy-intensive, and time-consuming furnace-based carbonization. Ultimately, this light-driven upcycling strategy offers an efficient, self-sustained route for converting polymer waste into functional electrochemical materials.

Neutrophils are increasingly recognized as key orchestrators of the immunosuppressive tumor microenvironment, yet their intrinsic plasticity, short lifespan and resistance to genetic manipulation have impeded therapeutic targeting. Here, we report a non-pharmacological, biophysical immunomodulatory strategy based on cold atmospheric plasma (CAP) to reprogram tumor-associated neutrophils and restore antitumor immunity. We show that CAP simultaneously delivers reactive oxygen species and redox cues that inhibit mitophagy, thereby restoring mitochondrial membrane potential and oxidative metabolism in neutrophils. This metabolic reinstatement drives a shift from immunosuppressive to immunostimulatory phenotypes. In both syngeneic and humanized bladder cancer models, intravesical CAP reshapes the myeloid landscape, enhances T cell infiltration, suppresses tumor progression, and sensitizes tumors to PD-1 blockade. These findings establish CAP as a locoregional, drug-free biophysical modality capable of overcoming neutrophil-mediated immune suppression and provide a materials-based framework for modulating innate immunity in solid tumors.

Degenerative cervical myelopathy (DCM) is the most common cervical spine disorder encountered in the aging population that commonly presents with increased cervical kyphosis and impaired gait. Thus, the compounding effects of exaggerated head tilt, as a result of cervical deformity, may increase the risk of falling in individuals with DCM. What are the effects of cervical bracing and posture (i.e., kyphosis and lordosis) on outcomes relevant to the control of walking balance? This was an experimental study conducted in 15 healthy young adults. We used two discrete mechanical balance challenges designed to elicit walking-related instability. Specifically, participants walked with a series of cervical spine braces while responding to: (i) treadmill-induced slip perturbations to induce rapid reactive responses to unanticipated perturbations and (ii) a reactive lateral stepping as a goal-directed balance challenge. We used two-way repeated measures ANOVAs to determine the effect of bracing condition and balance challenges on (i) anterior-posterior and mediolateral margins of stability (MoSAP and MoSML) and (ii) reaction time and foot placement error. Our experimental manipulations successfully emulated cervical spine postures common to patient populations. Compared to unperturbed walking, treadmill belt decelerations elicited significantly smaller MoSAP and larger MoSML for all conditions, but elicited negative MoSAP indicative of instability only for braced conditions. Bracing did not increase foot placement errors during lateral reactive stepping compared to unbraced walking. However, only for kyphotic bracing did performance decrease with target distance. Individuals prescribed cervical immobilization or presenting with cervical deformities may be less capable of responding to balance challenges that could precipitate a fall in the community. We conclude that treating cervical spine deformities with cervical immobilization may benefit from educational materials and monitoring techniques to mitigate falls risks.

Photobases are materials that exhibit enhanced basicity in their excited states and play a significant role in applications such as photocatalytic chemical transformations, water splitting, and polymerization. In this study, we investigated the photobasicity of excitation dependent full color light emitting carbon Dots (C-Dots) and examined the role of nitrogen sites, specifically pyridinic, pyrrolic, and graphitic nitrogen in the core, along with various electron-donating (-NH2) and electron-withdrawing (-COOH) surface functional groups in regulating their photobase characteristics. Exploring the photobasic properties and proton transfer pathways of differently emitting C-Dots is challenging due to their complex internal structure. To address this, the ground- and excited-state pKa values, along with the protonation sites of different emitting C-Dots, were first determined using pH-metric titration. Furthermore, optical studies were carried out to investigate the photobase properties of the C-Dots. The combined results suggest the protonation pathways in various emitting C-Dots. In B-C-Dots, proton abstraction occurs directly at the core from water, whereas in G-C-Dots and R-C-Dots, protonation occurs with the assistance of functional groups present on the surface of the C-Dots upon the photoexcitation of C-Dots. Ultrafast spectroscopic measurements reveal that proton transfer occurs in different emitting C-Dots within 180-480 fs after excitation, with the fastest process observed in G-C-Dots at approximately 185 fs. Therefore, this study provides a strategy for controlling the photobasicity of C-Dots, which may open up promising applications in related fields.

A detailed cranioscopic and craniometric analysis of a skull with hypertelorism from the collection of the Department of Normal Anatomy at the S.M. Kirov Military Medical Academy. This analysis compared the forensic anthropological analysis with standard parameters and highlighted the role of museum materials in the study of craniofacial anomalies. The object of the study was the skull of an adult male. Classic craniometric methods were used. Particular attention was paid to interorbital distance measurements and nasal parameters. A cranioscopic visual examination was performed, documenting morphological abnormalities. The skull was found to belong to a Caucasian male aged 54.5±7.0 years. Characteristic signs of orbital hypertelorism with craniometric values exceeding standard values were identified, confirming the diagnosis of true orbital hypertelorism. Детальный краниоскопический и краниометрический анализ черепа с признаком гипертелоризма из коллекции кафедры нормальной анатомии ВМедА им. С.М. Кирова, сравнительный судебно-антропологический анализ с нормативными параметрами и освещение роли музейных материалов в изучении краниофациальных аномалий. Объектом исследования был череп взрослого человека мужского пола. Применяли классические краниометрические методы. Особое внимание уделяли измерениям межорбитальных расстояний и параметрам носа. Проводили краниоскопический визуальный осмотр с фиксацией морфологических отклонений. Установлено, что череп принадлежал мужчине европеоидной расы 54,5±7,0 года. Выявлены характерные признаки орбитального гипертелоризма с превышением нормативных краниометрических значений, что подтверждает диагноз истинного орбитального гипертелоризма.

Analysis and comparison of impedance parameters of cadaveric tissues and their dynamics depending on the number of accumulated degree-days. Materials and methods: the experiment was carried out on model objects - pig cadavers (skin flap, cartilage, tendon) under two conditions: standardized (+4 °C, humidity around 40%, condition I) and natural biocenosis (average temperature around +18.5 °C, condition II). The impedance modulus and phase shift angle θ were measured at five frequencies f (100 Hz, 120 Hz, 1 kHz, 10 kHz, 100 kHz) at different times of the postmortem interval; a Keysight U1733 device was used. Various coefficients were calculated for dispersion analysis, and time referencing was carried out by calculating the number of accumulated degree-days. Measurements were also carried out on embalmed anatomical preparations. The study demonstrates that calculating accumulated degree-days allows for the reconciliation and quantitative comparison of changes in the impedance characteristics of cadaveric tissues obtained under various environmental conditions. An important result is that similar values of accumulated degree-days (~300 degree-days) correspond to similar qualitative changes in tissues under standardized and natural conditions, and the θ-lgf trend equations for similar values of accumulated degree-days coincide or are close in coefficients. This confirms the predictive value of calculating the number of accumulated degree-days when interpreting impedance measurements to clarify the duration of the postmortem period and the possibility of extrapolating results obtained under certain temperature conditions to other environmental conditions. However, further research is needed to explore the mechanisms of postmortem biophysics, expand the sample size (including human cadavers), examine the influence of entomological and other factors, and validate the methodology for practical use in forensic practice. Анализ и сравнение импедансометрических показателей тканей трупа и их динамики в зависимости от количества накопленных градусо-дней. Эксперимент проводили на модельных объектах — трупах свиней (кожный лоскут, хрящ, сухожилие) в двух условиях: стандартизованные (+4 °C, влажность около 40%, условие I) и естественный биоценоз (средняя температура около +18,5 °C, условие II). Измеряли модуль импеданса и угол сдвига фаз θ на 5 частотах f (100, 120 Гц, 1, 10, 100 кГц) в разные сроки постмортального интервала; использовали прибор Keysight U1733. Для анализа дисперсии рассчитывали разные коэффициенты, а временну́ю привязку проводили через расчет количества накопленных градусо-дней. Также осуществляли измерения на забальзамированных анатомических препаратах. Проведенное исследование демонстрирует, что расчет накопленных градусо-дней позволяет согласовать и количественно сопоставить изменения импедансометрических характеристик тканей трупа, полученные в разных внешнесредовых условиях. Важный результат — близкие значения накопленных градусо-дней (~300 градусо-дней) соответствуют аналогичным качественным изменениям тканей в стандартизированных и естественных условиях, а уравнения трендов θ—lgf для близких значений накопленных градусо-дней совпадают или близки по коэффициентам. Исследование подтверждает прогностическую значимость подхода с расчетом количества накопленных градусо-дней при интерпретации импедансометрии для уточнения продолжительности посмертного периода и возможности экстраполяции результатов, полученных при одних температурных режимах, на другие внешнесредовые условия. Однако необходимы дальнейшие исследования механизмов постмортальной биофизики, расширения выборок (включая трупы человека), проверки влияния энтомологического и некоторых других факторов и валидации методики для практического использования в практической судебно-медицинской деятельности.

Electron donor-acceptor (EDA) complexation has emerged as a sustainable strategy for visible-light-driven reactions. Although numerous EDA-based transformations have been applied to small aromatic molecules, conjugated polymers (CPs) have not yet been explored as substrates for EDA-mediated functionalization. Polymer-based EDA complexes comprise extended π-conjugation systems that reduce exciton-binding energy and facilitate red-shifted absorption, thereby enabling efficient visible-light harvesting. These characteristics are expected to intrinsically promote photoinduced functionalization. Here, we demonstrate the photochemical phosphonylation of poly(9,9-dioctylfluorene) (PFO) induced via the visible-light activation of its EDA complex. Compared with a monomeric model compound, the reaction of PFO proceeded more efficiently, indicating that CPs are promising substrates for EDA-excitation-initiated photochemical transformations. Phosphonylation predominantly proceeded at the 4-position of the fluorene units, thereby preserving the effective π-conjugation length of the polymer backbone. Furthermore, density functional theory calculations revealed that the greater stability of the intermediate species and the lower excitation energy required for 4-position substitution favored that pathway over 3-position substitution. This study establishes a new platform for integrating CPs into EDA-mediated photochemical reactions, offering a facile and sustainable route for the synthesis of versatile functional polymer materials.

The cleanup of persistent microplastics (MPs) from aquifers requires the capture and removal of a broad range of MP sizes and shapes. Conventional methods such as filtration and centrifugation are inefficient in removing such a broad range of particle sizes. We designed a class of biomimetic cleaners inspired by natural systems-including "Sargassum rafts" that trap MPs within their branched thalli and "Neptune balls" formed from seagrass. The cleaners are in the form of porous meshes and balls made of biopolymers such as alginate and chitosan. The biopolymers are reprocessed morphologically into soft dendritic colloids (SDCs). The SDCs are consolidated in a honeycomb-like internal network surrounded by a hierarchically fibrillar outer layer. This mesh architecture enables adsorption of nano- and microscale particles via van der Waals and electrostatic interactions while physically trapping millimeter-scale particles into the net openings. Similar cleaners from architected sustainable materials could serve as scalable systems for efficient removal of diverse MPs from aquatic environments.

Marine natural products reflect evolutionary adaptations of marine organisms to their environments. Natural products are biosynthesized via enzymatic and nonenzymatic reactions to serve specific biological functions intra- or interspecifically. The variety of their skeletons and building blocks, together with three-dimensional attributes, such as chirality, shape, and symmetry, has made marine natural products important for the development of advanced materials and pharmaceuticals. Here, an integrated structural analysis of hundreds of new marine terpenoids and meroterpenoids isolated from Indonesian waters is presented, revealing new building blocks, skeletons, and scaffolds, together with previously known structural elements having potential applications in many fields. The present study also discusses isolation, structural determination, and significant biological activities of marine terpenoids and meroterpenoids. Moreover, a new perspective on classification of these molecules based on plausible biosynthetic analyses is also suggested.

Despite the proliferation of lasing reports in three-dimensional (3D) lead halide perovskites, robust lasing in their single-layer two-dimensional (2D) counterparts, (LA)2PbX4 (LA = spacer cation; X = halide), has remained elusive. Here, we uncover the critical role of metal ns2-lone-pair stereochemistry in modulating excitonic properties and enabling lasing in these materials. Using a library of (LA)2BI4 [B = Pb (lead), Sn (tin), or Ge (germanium)], we identify key structural descriptors that link lone pair activity to exciton-phonon coupling and exciton-exciton annihilation. Within a given B-cation series, rigid frameworks with shorter B─I bonds suppress lone pair activity and favor free exciton emission, while enhanced lone pair activity-tuned by the spacer and B-cation-can localize excitons, increase dielectric screening, and suppress exciton-exciton annihilation at high excitation fluences. By balancing these effects through cation selection, we demonstrate lasing in a newly synthesized Pb-based (2FBMZ)2PbI4 (2FBMZ = 5,6-difluoro-1H-benzimidazole cation) and achieve the most thermally stable lasing in its Sn-based analog. These insights provide design principles for high-brightness 2D perovskite photonic devices.

Drowning represents one of the most frequent causes of accidental death; however, many submerged remains remain unrecovered or unidentified due to the challenges associated with aquatic decomposition. This process differs substantially from decomposition on land and is influenced by a complex array of factors, including temperature, oxygen availability, depth, and the presence of necrophagous organisms. In aquatic environments, decomposition follows a nonlinear trajectory and can be either slowed - under hypoxic conditions or at low temperatures - or accelerated by the activity of scavenging organisms. In marine ecosystems, key contributors to soft tissue degradation include crustaceans (such as crabs, shrimp, and lobsters), fish, and other invertebrates (e.g., polychaete worms and mollusks). Their activity leads to rapid skeletonization. Subsequently, the remains are colonized by fouling organisms (including barnacles and bivalves) and undergo bioerosion by specialized species such as the bone-devouring worms of the genus Osedax. In freshwater environments, the main participants in the process are leeches, flatworms, insects, and crustaceans. Their sequential succession ensures complete recycling of organic material. The rate of decomposition is highly variable, ranging from several days to several months, complicating the estimation of the postmortem submersion interval. Biological indicators, such as the developmental stage of barnacles, are used to address this challenge. Многие тела в водоемах остаются необнаруженными или неопознанными из-за сложностей, связанных с подводным разложением. Данный процесс существенно отличается от наземного разложения и зависит от комплекса факторов, включая температуру, доступность кислорода, глубину и присутствие некрофагов. В водной среде разложение протекает нелинейно и может как замедляться (в условиях гипоксии или низких температур), так и ускоряться вследствие деятельности падальщиков. В морских экосистемах ключевую роль в деградации мягких тканей играют ракообразные (крабы, креветки, омары), рыбы и другие беспозвоночные (многощетинковые черви, моллюски). Их активность приводит к быстрому скелетированию, и останки в дальнейшем колонизируется организмами-обрастателями (усоногие раки, двустворчатые моллюски) и подвергаются биоэрозии со стороны специализированных видов, таких как костные черви Osedax. В пресных водоемах основными участниками процесса являются пиявки, планарии, насекомые и ракообразные, последовательная сукцессия которых обеспечивает полную утилизацию органического вещества. Скорость разложения крайне вариабельна и может составлять от нескольких дней до месяцев, что затрудняет оценку времени пребывания тела в воде. Для ее установления используются биологические индикаторы, например стадия роста усоногих раков.

Calcium phosphate graphene (CaPG) is a promising reinforcement for polymeric bone matrices, yet the impact of graphene oxide (GO) oxidation on CaPG chemistry and matrix performance remains unclear. Our previous work demonstrated that 5 wt% CaPG provides optimal mechanical and biological performance of poly (lactic-co-glycolic acid) (PLGA) matrix. The present study isolates GO oxidation as the sole variable while maintaining a fixed 5 wt% CaPG loading. CaPG was synthesized under three oxidation conditions: Low Phosphate-High Oxygen at 50 °C, High Phosphate-High Oxygen at 100 °C, and High Phosphate-Low Oxygen at 156 °C and incorporated into the PLGA microspheres. Our results have shown that oxidation state regulates oxygen functional group density, calcium phosphate incorporation, hydrophilicity, and hydration behavior, which collectively modulate mechanical properties and osteogenic activity of the matrix. These findings demonstrate that oxidation can serve as a key tunable factor that generates distinct physicochemical and biological profiles, establishing oxidation programming as a practical approach for creating adaptable CaPG-reinforced PLGA matrices for diverse bone regeneration needs.

Long-term warfarin therapy following prosthetic heart valve placement is essential for preventing valve-related thromboembolic complications. Due to its narrow therapeutic window, maintaining a therapeutic International Normalized Ratio (INR) requires strict adherence to healthcare medication, dietary recommendations, and regular monitoring. Despite receiving education at discharge, patients with prosthetic heart valves continue to demonstrate poor adherence to warfarin therapy. While previous quantitative studies have identified factors associated with non-adherence, little is known about patients' day-to-day experiences and challenges with long-term warfarin use in low-resource settings. This study explored day-to-day experiences and challenges encountered during long-term warfarin use among patients with prosthetic heart valves attending a National Cardiac Institute in Dar es Salaam, Tanzania. An explorative qualitative study design using inductive content analysis was conducted among twelve (12) patients with prosthetic valves on long-term warfarin therapy, who were purposively recruited based on the principle of data saturation between April 2025 and June 2025 at a national cardiac institute. In-depth interviews were conducted using a semi-structured interview guide. Data were analyzed manually using a deductive-inductive content analysis approach. Two main categories emerged from this study. The first category, adapting to life with long-term warfarin use, describes participants' experiences of symptom relief and improved quality of life after surgery, alongside issues related to dietary restrictions, medication side effects, emotional distress, and reduced engagement in socio-economic activities. Participants perceived dietary recommendations as restrictive and reported difficulties with lifestyle modifications required during long-term warfarin therapy. The second category, navigating warfarin care within an unstructured continuum of care, reports participants' struggles in maintaining therapeutic INR levels amid financial difficulties, inconsistent medication use, contradictory information from healthcare providers, and limited access to INR monitoring and warfarin services in peripheral regions. Some participants reported self-adjusting warfarin doses or missing follow-up appointments due to cost and accessibility barriers. Although participants experienced clinical improvement post-surgery, they continued to face substantial challenges related to long-term warfarin use and access to anticoagulation care. Strengthening patient-centered education, improving continuity and consistency of anticoagulation counselling, decentralizing warfarin and INR monitoring services, and enhancing structured long-term follow-up systems may improve warfarin adherence and patient outcomes in low-resource settings.