Changes In Composition Research Articles

High temperature properties of nichrome resistant heaters – A systematic comparison of APS, suspension and filament HVOF sprayed coatings

This study investigates the performance of Nichrome coatings, a nickel‑chromium alloy containing 20 wt.-% chromium, applied using three thermal spray techniques: powder plasma spray, suspension HVOF, and filament HVOF. Thin, homogeneous coatings approximately 35 μm thick were deposited onto steel substrates pre-coated with an insulating Al2O3 layer. The oxide content in the coatings varied based on the spraying technique and parameters, ranging from 57 to 64 vol.-% for plasma spraying, 42 to 54 vol.-% for filament HVOF, and 9 to 43 vol.-% for suspension HVOF. The coating's heating performance was evaluated over a temperature range of room temperature (RT) to 700 °C. Analytical techniques such as X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Energy Dispersive X-ray Spectroscopy (EDS) were employed to investigate the mechanisms affecting temperature-dependent resistivity in relation to the coating microstructure. The results indicate that increased oxidation leads to a decrease in specific resistivity at RT (ρ0). In example, plasma sprayed coatings exhibited lower specific resistivity ρ0 of 0.80 Ωmm2/m. In contrast, suspension HVOF reaches values up to 2.75 Ωmm2/m. At the same time coatings with higher oxidation levels demonstrate an elevated dependence of resistivity as compared to less oxidized coatings. Both can be attributed to changes in the phase composition of the conductive phase as the dominating factor, primarily driven by the preferential oxidation of chromium during the spraying process. Notably, the results provide valuable information for adjusting the coating properties to suit specific needs, such as self-regulating or high-temperature heating applications.

Infrared Thermography: A Non-Invasive Way to Assess Animal Health and Productivity

Abstract Dairy cattle may experience stress and anxiety due to rough handling by humans, extreme weather conditions, change in feed, social grouping, transportation, and limited access to pasture. Stress is the body’s response to a threat, while anxiety is persistent stress that impacts physical and psychological health. Cows experiencing consistent stress or anxiety tend to eat less, produce less milk, have reproductive issues, change in milk composition, spend more time being vigilant and are more prone to illness and mortality. Infrared thermography (IRT) detects temperature changes in an animal’s body caused by stress or anxiety. It measures heat radiation emitted from the body’s surface using an infrared sensor from a distance. Studies have shown that IRT of the eyes has the potential to automate the assessment of cow health, monitor changes in milk composition, and differentiate between sick and healthy animals, unlike rectal temperature recording, behavioural assessment, and milk composition tests. IRT of the eyes was found to be repeatable and positively correlated with rectal temperature, unlike rectal temperature measurements, which were found to be non-reproducible. Further research and refinement of IRT of the eyes could improve automated cow health monitoring and management. Information © The Author 2024

Polyethylene glycol/carboxymethyl cellulose/montmorillonite composite phase change materials for thermal management

The fabrication of composite phase change materials (CPCMs) with excellent shape stability, reasonable thermal conductivity and good mechanical properties using simple process to obtain an effective energy storage and conversion maintains an issue of the utmost importance. In this work, carboxymethylcellulose sodium (CMC)/montmorillonite (MMT) aerogels with various MMT loading is initially prepared by gelation and freeze-drying technique. The prepared CMC/MMT aerogels have a uniformly distributed pore structure, of which the compressive strength can reach 26.4 kPa when the MMT loading content is 40 wt%. When the MMT loading content is 40 wt%, the thermal conductivity of the PEG/CMC/40MMT CPCM can reach up to 0.78 W/m·K, which is 225 % higher than that of pure PEG. In particular, the rigid CMC/MMT composite aerogel is conducive to the storage of PEG, obtaining a maximum loading percentage of 96.8 %, phase change enthalpy of 179.2 J/g, and high enthalpy efficiency of 98.6 % for CMC/40MMT aerogel. The rigid supporting matrix and adsorption capacity of the CMC/MMT framework meliorate the shape stability and cyclic stability during the phase transition, which can also cool the surface temperature of a simulated central processing unit (CPU) from 90 °C to 54.7 °C. In summary, the as-prepared novel PEG/CMC/40MMT CPCM offers a novel strategy for thermal management of next-generation electronic devices.

Invasive Fascioloides magna infections impact gut microbiota in a definitive host in Europe

Invasive parasites that expand their natural range can be a threat to wildlife biodiversity and may pose a health risk to non-adapted, naive host species. The invasive giant liver fluke, Fascioloides magna, native to North America, has extended its range in Europe and uses mainly red deer (Cervus elaphus) as definitive hosts. The penetration of the intestinal barrier by the young flukes to reach the liver via the abdominal cavity as well as the release of fluke metabolism products and excreta with the bile and/or changes in the microbial community of the biliary system may enable the translocation of intestinal bacteria across the intestinal barrier and, in turn, could be associated with inflammation and changes in the intestinal bacterial community. The gut commensal community plays a key role in host nutrition and interacts with cells of the immune system to maintain host health. For this study, the gut bacterial community of red deer infected with F. magna and of non-infected red deer from one of the largest forest ecosystems in Central Europe, located on the border between the Czech Republic and Germany, was investigated. The individual fluke burden was associated with changes in the gut microbial composition of the gut of infected individuals, whereas the diversity and composition of the gut bacteria were only slightly different between fluke-infected and uninfected deer. Several bacterial taxa at the genus level were unique to individuals carrying either one or many liver flukes. Our results suggest that the microbiota of red deer is stable to perturbation by low numbers of F. magna. However, a larger parasite burden may cause changes in the gut microbial composition in definitive hosts implying that non-invasive fecal microbiome assessments could serve as indicator for wildlife health monitoring.

Biocrusts Mediate the Niche Distribution and Diversity of Ammonia-Oxidizing Microorganisms in the Gurbantunggut Desert, Northwestern China

Biological soil crusts (biocrusts) play pivotal ecological roles in regulating nitrogen cycling within desert ecosystems. While acknowledging the essential role played by ammonia-oxidizing microorganisms in nitrogen transformation, there remains a paucity of understanding concerning how disturbances to biocrusts impact the diversity and spatial distribution patterns among ammonia oxidizer communities within temperate deserts. This investigation delved into assessing how 4 years’ worth of removing biocrust influenced niche differentiation between nitrifying archaea and bacteria while also examining its effects on shaping community structures of predominant ammonia-oxidizing archaea (AOA) within the Gurbantunggut Desert soils. Despite notable variations in abundance of ammonia-oxidizing microbes across distinct soil depths throughout different seasons, it became apparent that removing biocrust significantly altered both the abundance and niche pattern for AOA alongside their bacterial counterparts during winter and summer periods. Notably dominating over their bacterial counterparts within desert soils, AOA displayed their highest archaeal to bacterial amoA gene copy ratio (6549-fold higher) at a soil depth of 5–10 cm during summer. Moreover, substantial impacts were observed upon AOA diversity along with compositional changes following such perturbation events. The aftermath saw an emergence of more diffuse yet dynamic AOA communities, especially noticeable amidst winter when nitrogen and water limitations were relatively alleviated. In summary, our findings underscore how interactions between biocrust coverages alongside factors like soil temperature, total carbon content, or NO3−_N concentrations govern niches occupied by ammoxidation communities whilst influencing assemblage processes too. The sensitivity shown by dominant AOAs towards biocrust removal further underscores how biocrust coverage influences nitrogen transformation processes while potentially involving other communities and functions in desert ecosystems.

Acoustic richness and composition changes of humpback whale (Megaptera novaeangliae) songs on breeding grounds off the coast of Ecuador

AbstractSong evolution and revolution events recorded through time are typical cultural features for humpback whale (Megaptera novaeangliae) populations worldwide. However, it is unknown if song dynamics are equivalent among subpopulations or breeding stocks of the South Pacific Ocean. To contribute to the understanding of the temporal song dynamics of humpback whale song off the coast of Ecuador, we analyzed acoustic richness and repertoire composition based on unit, phrase, and song composition over consecutive breeding seasons from 2012 to 2019. We observed incomplete song revolutions (all themes were replaced except one) and a nonsignificant variation in the acoustic richness during the study period. Our results show that over the years, humpback whale singers incorporate acoustic material from different subpopulations such as Central South Pacific (French Polynesia) and western South Atlantic (Brazil) into their song repertoire. The temporal acoustic contact of different subpopulations migrating through the eastern South Pacific may be reflected in their particular acoustic richness and temporal evolution. Off the coast of Ecuador, humpback whale song patterns point towards an alternative scenario of song evolution, indicating how cultural transmission among subpopulations can alter the song patterns in specific breeding grounds due lack of geographical barriers surrounding the southeastern Pacific region.

Transformation of Natural Organic Matter in Simulated Abiotic Redox Dynamic Environments: Impact on Fe Cycling.

Redox fluctuations within redox dynamic environments influence the redox state of natural organic matter (NOM) and its interaction with redox-active elements, such as iron. In this work, we investigate the changes in the molecular composition of NOM during redox fluctuations as well as the impact of these changes on the Fe-NOM interaction employing Suwannee River Dissolved Organic Matter (SRDOM) as a representative NOM. Characterization of SRDOM using X-ray photoelectron spectroscopy and Fourier transform infrared spectrometry showed that irreversible changes occurred following electrochemical reduction and reoxidation of SRDOM in air. Changes in the redox state of SRDOM impacted its interaction with iron with higher rates of Fe(III) reduction in the presence of reduced and reoxidized SRDOM than in the presence of the original SRDOM. The increased rate of Fe(III) reduction in the presence of reduced SRDOM was due to the formation of reduced organic moieties on SRDOM reduction. The Fe(II) oxidation rate also increased in the presence of reduced SRDOM due to the formation of redox-active moieties that were capable of oxidizing Fe(II). Overall, our study provides useful insights into the changes in SRDOM that may occur in redox dynamic environments and the associated impact of these changes on Fe transformations.

Changes in Biochemical Composition and Nutrient Materials in Apocynum pictum Honey During Storage

Apocynum pictum (A. pictum) honey is rich in effective ingredients including flavonoids, terpenes, and alkaloids that are beneficial to human health. In this study, widely targeted metabolomics were used to detect the plant-derived secondary metabolites of the same batch of A. pictum honey from 2022 to 2024, in order to explore whether storage time changes the quality of A. pictum honey, especially the content of plant-derived secondary metabolites with important health benefits. The results showed that storage time had no significant effect on the content of sugars, proteins, and other major components in A. pictum honey. At the same time, we also found that although storage time had an impact on the content of some secondary metabolites such as flavonoids in A. pictum honey, the changes in the content of the characteristic active ingredient, hyperoside, in A. pictum honey were not significant. These findings suggest that storage time has a minimal impact on the quality of A. pictum honey. This study provides a theoretical basis for the rational storage of A. pictum honey.

Determination of changes in bioactive components and fatty acid compositions of olive fruits sonicated in different bitterness removal solutions in pickled olive production

Determination of changes in bioactive components and fatty acid compositions of olive fruits sonicated in different bitterness removal solutions in pickled olive production

Active restoration efforts drive community succession and assembly in a desert during the past 53 years.

Regreening efforts in deserts have been implemented globally to combat land degradation and desert expansion, but how they affect above- and belowground community succession and assembly processes remains unknown. Here, we examined variations in plant and soil microbial community attributes along a 53-year restoration chronosequence following the establishment of straw checkerboard barriers (SCBs) in the Tengger Desert of China. This approach is a combination of fixing shifting sand and adding organic material (straw) simultaneously to expedite vegetation restoration by enhancing the success of plant establishment. Our findings revealed that the establishment of SCBs significantly triggered plant and soil microbial communities to gradually approximate those of the natural community along restoration duration. We observed positive and negative bidirectional shifts in plant and soil microbial community composition. Critical temporal threshold zones for relatively rapid changes in community composition were identified, with 2-15.5 years for plants, 0.5-8.5 years for bacteria, and 2-8.5 years for fungi. This suggests a delayed response of plant communities to restoration efforts compared with soil microbial communities. Both stochastic and deterministic processes regulated plant and soil microbial community assembly. Stochastic processes played a more important role in plant and fungal community succession, whereas deterministic processes primarily governed bacterial succession. In terms of deterministic processes, temporal variations in community composition mainly resulted from the intrinsic correlations among plant, bacterial, and fungal communities, as well as an increase in soil organic carbon (SOC) with restoration duration. Thus, temporal patterns and functional contributions of bacterial communities appear to be more predictable than those of plant and fungal communities during desert ecosystem restoration. This study emphasizes that plant-bacteria-fungi correlations and increasing SOC content are critical for accelerating community succession and promoting dryland restoration. Future studies should explore and integrate temporal variations and restoration effects of multiple ecosystem functions to better predict dryland development and resilience to global climate changes over a large temporal scale.

Resting metabolic rate and energy efficiency in response to an intensive 84-day combat-swimmer training in the German Armed Forces

Abstract Purpose According to the ‘constrained model’, there are compensations in resting metabolic rate (RMR) at high levels of physical activity (PA). Here, we have used a standardized combat-swimmer training protocol (CST) to investigate whether changes in RMR (i) confirm the ‘constraint model’, and (ii) differ between successful participants and dropouts. Methods Controlled 84d CST in 44 male soldiers with 13 finally successful. Fat mass (FM) and fat-free mass (FFM) were measured using Quantitative Magnetic Resonance. RMR was assessed by indirect calorimetry, VO2max, and work efficiency by treadmill spiroergometry. Plasma levels of thyroid hormones, testosterone, and cortisol were analysed by standard laboratory methods. Results CST increased VO2max (+ 6.9%) and exercise efficiency at low workloads of 10 and 12 km/h (+ 8.7 and + 6.5%; both p < 0.05). As energy balance was moderately negative (−356 ± 383 kcal/d), FFM and FM decreased (−2 and −16%; both p < 0.05). There was a considerable inter-individual variance but no change in in the mean values of RMR and RMRadjFFM. RMRadjFFM before CST had a negative association with its decrease with CST (p < 0.005). Concomitantly, plasma hormone levels were unchanged. When compared with dropouts, successful participants had a higher VO2max at baseline (5.2 ± 0.6 vs. 4.9 ± 04 l/min; p < 0.05) that increased with CST (+ 4.4 vs. −0.4%; p < 0.05) at similar changes in body composition and energy balance. Conclusion While CST increased VO2max and exercise efficiency as a compensation, there was an inter-individual variance in exercise-related compensation of RMR with no differences between ‘completers’ and ‘non-completers’. Trial registration DRKS00018850, November 27, 2019.

Application of antimicrobial edible film incorporated with Caulerpa racemosa crude extract as active packaging of seaweed dodol

Using seaweed-based antimicrobial edible films containing antimicrobial seaweed extracts in food products has maintained product quality during storage. Caulerpa extracts have the potential to be antimicrobial and antioxidant agents. However, no research has been conducted regarding applying Caulerpa extract edible film to semi-wet food products, especially seaweed dodol. This study examines changes in the chemical composition and shelf life of seaweed dodol packaged with antimicrobial edible films made from agar added with crude extract of Caulerpa racemosa. The study employed a completely randomized design with two variables: packaging type and storage duration. The packaging types included an unpackaged (control), an antimicrobial edible coating (AEC), and the antimicrobial edible film (AEF), while the storage period was set to 6 days. The observed research parameters included changes in chemical quality and total microbes. Data on changes in the composition of free fatty acids and total plate numbers are also used to calculate shelf life. The results showed that using AEF as the primary packaging of seaweed dodol can inhibit changes in chemical composition during storage, especially moisture, carbohydrates and fats. The barrier to moisture and oxygen from AEF inhibits the chemical composition deterioration of the coated food product, which has an impact on increasing the product's shelf life. Seaweed dodol packaged with AEF demonstrated an extended shelf life by 2 days compared to both the control and AEC-packaged samples. Antimicrobial edible film of crude extract of C. racemosa has the potential to be developed as primary packaging in semi-wet food products.

Extent of Benthic Habitat Disturbance by Offshore Infrastructure

The effects of the interaction between sandy, mobile, low-relief (sorted) bedforms and two sewage outfalls were investigated along the south shore of Long Island, NY. Sand bedforms at scales from ripples to ridges are common on continental shelves. In dynamic environments, these features can migrate 10s to 100s of meters per year, especially during storms. Beyond engineering considerations, little is known of the interaction between these mobile features and anthropogenic structures. Modification of bedform topography and sediment grain-size distribution can be expected to alter the species composition, abundance, and diversity of the benthic community. At the study site, the interaction increased the scour of modern fine- to medium-grained sediments extending out to a kilometer and uncovered coarser-grained late Pleistocene sediments. This alteration of the seafloor in turn resulted in changes in composition, higher abundance, and lower diversity in the species assemblage found in the impacted area. The most advantaged species was Pseudunciola obliquua, a sightless, tube-building, surface deposit-feeding amphipod that is known to prefer a dynamic coarse sand habitat. Overall, the ecological effects of artificial structures on a wave-dominated seabed with sorted bedforms have not been adequately assessed. In particular, and of great importance, is the pending large-scale development of wind farms off the East Coast of the U.S.

Body Composition and Incident High-Intensity Back Pain and/or High Disability: A 10-Year Prospective Population-Based Male Cohort.

Back pain poses a significant global burden, within which individuals with more severe symptoms consume higher healthcare expenses than those with lesser back pain. Whether measures of body composition predict high-intensity back pain and/or high-disability in population-based cohorts is unknown. This study aimed to examine the association between body composition at baseline and their change in the prior 5 years (between 2001-2005 and 2006-2010) and incident high-intensity back pain and/or high-disability in long-term follow-up, 10 years later (2016-2021) in a population-based cohort of men. This study examined men with no or low-intensity back pain and disability (Graded Chronic Pain Scale) at back pain study baseline (2006-2010) within the Geelong Osteoporosis Study. Those developing high-intensity pain and/or high disability at follow-up (2016-2021) were identified. Weight, body mass index (BMI), abdominal circumferences, fat mass and lean mass (dual energy X-ray absorptiometry) were assessed prebaseline (2001-2005) and at baseline. The association of body composition at baseline and change in body composition from prebaseline to baseline with incident high-intensity pain and/or high disability at follow-up were examined using multivariable logistic regression. Of 695 participants with no or low-intensity pain and disability at baseline, 441 (62.3%) completed follow-up with a mean age of 54.3 ± 14.1 years: 37 (8.3%) developed high-intensity pain and/or high-disability, 33 (7.5%) developed high-intensity pain and 14 (3.2%) high disability. No measures of body composition at baseline were associated with incident high-intensity pain and/or high disability at follow-up in the whole population. In subgroup analysis, among men aged over 60 years, but not younger, higher lean mass was associated with decreased likelihood of high-intensity pain and/or high-disability (odds ratio [OR] 0.86, 95% confidence interval [CI] 0.76, 0.97, interaction p < 0.001). In the whole population, examination of the relationship between change in measures of body composition between prebaseline and baseline, only a one unit increase in BMI, equivalent to 3.1-kg weight gain, was associated with increased incident high disability (OR 1.63, 95% CI 1.06, 2.51). In a population-based sample, without severe back pain and disability, in older men aged ≥60 years, higher lean mass was protective of incident high-intensity pain and/or high disability. An increase in BMI, over 5 years, equivalent to 3.1-kg weight gain, was associated with incident back pain related high disability 10 years later. These results demonstrate another detrimental consequence of weight gain and highlight the importance of maintaining muscle mass in older men.

Preparation and assessment of a novel hydrated salt PCM applied for intermittent floor radiant heating systems

Intermittent floor radiant heating is widely employed in building heating systems. However, it suffers large indoor air temperature fluctuations due to its intermission. The integration of phase change material (PCM) can significantly mitigate this issue. In this study, Na2HPO4·12H2O and Na2SO4·10H2O were used as raw materials, with expanded perlite (EP) as the porous medium, to prepare a shaped composite phase change material (EPPCM). This material was then blended into mortar to produce a novel phase change mortar (EPPCM-M). Experiments were carried out to evaluate its heat storage performances. Compared to normal mortar, EPPCM-M of 25 mm thickness mitigates temperature fluctuations, with the peak temperature on the cold end reduced by about 2.5 °C and a slower cooling rate on the hot end. To assess the practical application of EPPCM in buildings, a simulation study was conducted. A room model of 4 × 4 × 3 m was built and subjected to radiant floor heating for 8 h daily, under the winter climate conditions of Shanghai from November 15th to March 14th. The results showed that the EPPCM-M can effectively suppress temperature fluctuations in both the floor surface and average indoor air temperatures. From February 27th to March 5th, the maximum fluctuation of floor surface temperature was reduced by 55.4 %, the maximum fluctuation of average indoor air temperature was reduced by 39.5 %. The application of the EPPCM-M in intermittent floor radiant heating not only ensures indoor thermal comfort but also achieves heat's “peak load shifting”, improving indoor comfort, reducing heating energy consumption, and promoting building energy efficiency.

Preparation and characterization of modified steel slag-based composite phase change materials

In order to promote the resource utilization in steel slag and reduce the environmental hazards caused by steel slag, a steel slag-based composite phase change material was prepared in this experiment. Steel slag had a porous structure with good structural stability, which could be used to prepare composite phase change materials and applied in fields such as thermal energy storage and waste heat recovery. To enhance the adsorption capacity of steel slag on phase change materials, the impact of acid or alkali modifiers on steel slag was meticulously examined. The investigation revealed that the pore structure of the modified steel slag was markedly enhanced, accompanied by a notable improvement in adsorption capacity. Among the results, the adsorption rate of the acid washed modified steel slag for paraffin reached 35 %, with the phase change temperature and latent heat of phase change being 53 °C and 60 J/g. Acid washing had a significant impact on the pore structure of the steel slag, with the adsorption rate of the acid washed modified steel slag for paraffin being approximately twice that of the unmodified steel slag.

Single-molecule imaging reveals the kinetics of non-homologous end-joining in living cells

Non-homologous end joining (NHEJ) is the predominant pathway that repairs DNA double-stranded breaks (DSBs) in vertebrates. However, due to challenges in detecting DSBs in living cells, the repair capacity of the NHEJ pathway is unknown. The DNA termini of many DSBs must be processed to allow ligation while minimizing genetic changes that result from break repair. Emerging models propose that DNA termini are first synapsed ~115 Å apart in one of several long-range synaptic complexes before transitioning into a short-range synaptic complex that juxtaposes DNA ends to facilitate ligation. The transition from long-range to short-range synaptic complexes involves both conformational and compositional changes of the NHEJ factors bound to the DNA break. Importantly, it is unclear how NHEJ proceeds in vivo because of the challenges involved in analyzing recruitment of NHEJ factors to DSBs over time in living cells. Here, we develop an approach to study the temporal and compositional dynamics of NHEJ complexes using live cell single-molecule imaging. Our results provide direct evidence for stepwise maturation of the NHEJ complex, pinpoint key regulatory steps in NHEJ progression, and allowed us to estimate the overall repair capacity of the NHEJ pathway in living cells.

Advancing biorefineries with ultrasonically assisted ionic liquid-based delignification: Optimizing biomass processing for enhanced bio-based product yields

Encouraging sustainable business needs utilization of bio-based substrate for green manufacturing of chemicals and fuels to achieve sustainable development goals set by the United Nations. One of the abundantly available bio-based substrates is lignocellulosic (LC) biomass, which requires effective pretreatment to fractionate into its structural biocomponents to maximize biorefinery potential. This study addresses the use of an inexpensive ionic liquid (triethylammonium hydrogen sulfate) [T2220][HSO4] in an ultrasound-assisted process as an environmentally acceptable pretreatment method for the delignification of LC biomass, specifically rice straw (RS). Using ionic liquid (IL)-assisted (IL, acid-IL, and alkali-IL) pretreatment procedures, the effects of IL volume, sonication time, and temperature were methodically examined for RS delignification. To evaluate the compositional changes in pretreated and raw RS, instrumental analyses were carried out. The maximum rates of 47 %, 55 %, and 64 % for the only IL, acid-IL, and alkali-IL treatments demonstrated the effect of temperature, operating time, and IL concentration on the delignification efficiency. The alkali-IL pretreatment was noteworthy for achieving a 64 % delignification rate under optimum values of IL volume (8.65 mL), sonication time (123 min), and temperature (82 °C). Artificial neural networks (ANN) and response surface methodology (RSM) were used for process modeling and optimization. With an accuracy of 0.989 in correlation coefficient, the ANN model outperformed the RSM regression model regarding forecasting delignification performance. Biorefinery of renewable biomass resources ensures the sustainable supply of materials, chemicals, and fuels. The delignification and downstream product recovery technologies are major limiting factors in the commercialization of biomass processing. The suggested [T2220][HSO4]-based ultrasonic approach provides a viable way to boost biomass valorization efficiency, which in turn improves economical and sustainable biorefinery and aids in the shift to green bio-based production.

Effects of environmental factors on natural aging of timber members of ancient buildings: Ultraviolet radiation, temperature and moisture

The main objective of this study was to investigate the effects of environmental factors on natural aging and the mechanism on larch (Larix principis-rupprechtii Mayr) timber. Firstly, 130 specimens were processed in the sapwood area of wild forest larch timber to investigate the effects of ultraviolet (UV) irradiation time and the number of dry and wet (D-W) cycle on color, physical and mechanical properties of timber specimens. And then a multifactor level tests were designed according to the response surface methodology (RSM) to analyze the compound effects of each factor on the natural aging of timber based on the established artificial accelerated aging device. Finally, the changes in the chemical composition and microstructure of timber and the natural aging mechanism were investigated by infrared (IR) spectral analysis and scanning electron microscopy (SEM) observation. The results showed that the color of wood was significantly affected by UV and DW cycle aging, in addition, the density and bending properties of wood decreased significantly in DW cycle, while the effect of UV irradiation was weak. In addition, the effects strengths of environmental factors of wood aging were UV, temperature and relative humidity by RSM analysis, and there were obvious temperature and moisture dependence of UV aging of timber. IR and SEM analyses showed that the characteristic peaks representing cellulose and hemicellulose were weakened and the microstructure was impaired after natural aging, which is similar to the trend of analyses and observations of approximately 600 years old timber members obtained from ancient architecture in Beijing. The conclusions show that temperature and humidity accelerate UV radiation aging of timber, and that the D-W cycle has a significant effect on the physical and mechanical properties of timber.

A multi-region single nucleus transcriptomic atlas of Parkinson’s disease

Parkinson’s Disease (PD) is a debilitating neurodegenerative disorder, characterized by motor and cognitive impairments, that affects >1% of the population over the age of 60. The pathogenesis of PD is complex and remains largely unknown. Due to the cellular heterogeneity of the human brain and changes in cell type composition with disease progression, this complexity cannot be fully captured with bulk tissue studies. To address this, we generated single-nucleus RNA sequencing and whole-genome sequencing data from 100 postmortem cases and controls, carefully selected to represent the entire spectrum of PD neuropathological severity and diverse clinical symptoms. The single nucleus data were generated from five brain regions, capturing the subcortical and cortical spread of PD pathology. Rigorous preprocessing and quality control were applied to ensure data reliability. Committed to collaborative research and open science, this dataset is available on the AMP PD Knowledge Platform, offering researchers a valuable tool to explore the molecular bases of PD and accelerate advances in understanding and treating the disease.