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Air pollution consists of complex mixtures of chemicals with serious deleterious health effects from acute and chronic exposure. To help understand the mechanisms by which adverse effects occur, the present work examines the responses of cultured human epidermal keratinocytes to specific chemicals commonly found in woodsmoke. Our earlier findings with liquid smoke flavoring (aqueous extract of charred wood) revealed that such extracts stimulated the expression of genes associated with oxidative stress and proinflammatory response, activated the aryl hydrocarbon receptor, thereby inducing cytochrome P4501A1 activity, and induced cross-linked envelope formation, a lethal event ordinarily occurring during terminal differentiation. The present results showed that furfural produced transcriptional responses resembling those of liquid smoke, cyclohexanedione activated the aryl hydrocarbon receptor, and several chemicals induced envelope formation. Of these, syringol permeabilized the cells to the egress of lactate dehydrogenase at a concentration close to that yielding envelope formation, while furfural induced envelope formation without permeabilization detectable in this way. Furfural (but not syringol) stimulated the incorporation of amines into cell proteins in extracts in the absence of transglutaminase activity. Nevertheless, both chemicals substantially increased the amount of cellular protein incorporated into envelopes and greatly altered the envelope protein profile. Moreover, the proportion of keratin in the envelopes was dramatically increased. These findings are consistent with the chemically induced protein cross-linking in the cells. Elucidating mechanisms by which this phenomenon occurs may help understand how smoke chemicals interact with proteins to elicit cellular responses, interpret bioassays of complex pollutant mixtures, and suggest additional sensitive ways to monitor exposures.

Woody biomass is a large carbon store in terrestrial ecosystems. In calculating biomass, tree stems are assumed to be solid structures. However, decomposer agents such as microbes and insects target stem heartwood, causing internal wood decay which is poorly quantified. We investigated internal stem damage across five sites in tropical Australia along a precipitation gradient. We estimated the amount of internal aboveground biomass damaged in living trees and measured four potential stem damage predictors: wood density, stem diameter, annual precipitation, and termite pressure (measured as termite damage in downed deadwood). Stem damage increased with increasing diameter, wood density, and termite pressure and decreased with increasing precipitation. High wood density stems sustained less damage in wet sites and more damage in dry sites, likely a result of shifting decomposer communities and their differing responses to changes in tree species and wood traits across sites. Incorporating stem damage reduced aboveground biomass estimates by > 30% in Australian savannas, compared to only 3% in rainforests. Accurate estimates of carbon storage across woody plant communities are critical for understanding the global carbon budget. Future biomass estimates should consider stem damage in concert with the effects of changes in decomposer communities and abiotic conditions.

Specialty mushrooms have been implicated in foodborne illness outbreaks in the U.S. in recent years. These mushrooms are available to consumers in both their fresh and dried states. Dehydrating mushrooms is a convenient way to increase shelf life. The dehydration process results in a lowered water activity (aw) of the commodity, creating an environment where both spoilage and pathogenic bacteria cannot proliferate. Prior to food preparation and consumption, these mushrooms are typically rehydrated and possibly stored for later use which could lead to increased levels of pathogens. This study examined the survival and growth of Listeria monocytogenes and Salmonella enterica on dehydrated enoki and wood ear mushrooms during rehydration and subsequent storage. Mushrooms were heat dehydrated, inoculated at 3 log CFU/g, and rehydrated at either 5 or 25°C for 2 h. Rehydrated mushrooms were stored at 5, 10, or 25°C for up to 14 d. L. monocytogenes and S. enterica survived on enoki and wood ear mushroom types during rehydration at 5 and 25°C, with populations often <2.39 log CFU/g. During subsequent storage, no growth was observed on wood ear mushrooms, regardless of the rehydration or storage temperature, with populations remaining <2.39 log CFU/g for both pathogens. When stored at 5°C, no growth was observed for either pathogen on enoki mushrooms. During storage at 10 and 25°C, pathogen growth rates and populations after 14 d were generally significantly higher on the enoki mushrooms rehydrated at 25°C; the highest growth rate (3.56 ± 0.75 log CFU/g/d) and population (9.48 ± 0.62 log CFU/g) after 14 d for either pathogen was observed by S. enterica at 25°C storage temperature. Results indicate a marked difference in pathogen survival and proliferation on the two specialty mushrooms examined in this study and highlight the need for individual product assessments. Data can be used to assist in informing guidelines for time and temperature control for the safety of rehydrated mushrooms. [ABSTRACT FROM AUTHOR]

Wood‐derived carbons demonstrate great potential as self‐standing electrodes in energy storage/conversion applications, including supercapacitors and water‐splitting devices. However, the key challenge remains the rational customization of surface functionalities for optimized performance. This study introduces an innovative approach to self‐standing wood‐derived carbons with tailored nitrogen and metal functionalities. In contrast to traditional impregnation techniques, which offer limited precision in surface modification, this approach entails the intentional attachment of amidoxime groups to the wood substrates. These groups serve as nitrogen sources, and create abundant surface anchoring sites for metal ions due to the chelation between the amidoxime groups and metals. The resulting carbons feature uniform and high dispersion of nitrogen and metal functionalities, along with a distinctive hierarchical porosity combining interconnected open channels with abundant mesopores. As a proof‐of‐concept, different metals are incorporated (i.e., Mn, Co, Ni) into the amidoximated‐wood precursors, and the resulting self‐standing carbons showcase excellent performance in both supercapacitors and water‐splitting applications. Leveraging the specific chelating ability of amidoxime groups toward metal ions, this strategy holds great potential as a generic approach to systematically tailoring the surface functionalities of carbon‐based materials for various electrochemical energy storage/conversion processes. [ABSTRACT FROM AUTHOR]

Worldwide, silicified woods are found in many geological formations. Significantly, the organic materials of wood are no longer dominant; almost all wood fossils have been mineralized into inorganic silica materials. These unique geological processes must be understood to develop better understanding on organic material fossilization, particularly in the micron scale. Therefore, our aim was to characterize the composition of silicified wood using comprehensive microanalysis. The methods utilized were XRF, ICP-MS, XRD, FTIR, and FE-EPMA. Specimens are from Jasinga, West Java, Indonesia. The results showed that wood silicification was controlled by the infiltration of silica from the host rock into the spaces of the wood structure. In Jasinga, they are controlled by Pliocene tuffaceous sedimentary rocks. The ratio of silica phases revealed a trend in the degree of silicification. Besides silica, the distribution of trace elements also demonstrates the geochemical interaction between the wood fossil and host rock. Wood fossils are affected by the gradual replacement of organic carbon-based materials with silica through silicification. Silica enrichment occurs in the internal of wood, facilitates permineralization and recrystallization. Silica replaces organic material and preserves the wood structures. The microanalytical approach provides comprehensive perspectives on wood petrification, leads to better insights for paleontological studies. [ABSTRACT FROM AUTHOR]

The wood preservative disodium octaborate tetrahydrate (DOT) migration is studied in clay. Using boron analysis by inductively coupled plasma optical emission spectroscopy (ICP‐OES), DOT spatial and temporal dynamics are surveyed to show how DOT permeates into the wood and the clay using concentration profiles as a function of depth, initial wood moisture, and direction of filling. Atomic force microscopy and chemical imaging using photoinduced force microscopy are used to show the morphology of the wood samples and the distribution of DOT on their surface. ICP‐OES results show that the average DOT concentration in the wood samples is originally 0.8 and 1.5 wt% in the bulk and at the surface, respectively. Conditioning of the wood to a moisture content of 19% in a climatic chamber reduces DOT concentration by 8% for the fir and 17% for the spruce. After one week of contact with the clays, the results showed a rapid decrease of 25–40% in DOT concentration in wood. On longer periods (5 months), the spruce shows a tendency to reabsorb the DOT from the clay and the DOT migration stabilizes at 20%. These results contribute to defining the dosage of DOT when the wood is exposed to clay. [ABSTRACT FROM AUTHOR]

Bristlecone pine (Pinus longaeva) (PILO) trees exhibit exceptional longevity. Their tree‐ring width (TRW) series offer valuable insights into climatic variability. Maximum latewood density (MXD) typically correlates better with temperature variations than TRW, yet PILO MXD records are non‐existent due to methodological challenges related to tree‐ring structure. Here, we used an X‐ray Computed Tomography (X‐ray CT) toolchain on 51 PILO cores from the California White Mountains to build a chronology that correlates significantly (r = 0.66, p < 0.01) with warm‐season (March‐September) temperature over a large spatial extent. This led to the first X‐ray CT‐based temperature reconstruction (1625–2005 CE). Good reconstruction skill (RE = 0.51, CE = 0.32) shows that extending MXD records across the full length of the PILO archive could yield a robust warm‐season temperature proxy for the American Southwest over millennia. This breakthrough opens avenues for measuring MXD in other challenging conifers, increasing our understanding of past climate further, particularly in lower latitudes. Plain Language Summary: Ancient Bristlecone pine trees can live for several millennia and hold invaluable climate information. Their annual rings were used to develop millennium‐length records of the Holocene climate. Maximum latewood density (MXD), which is the highest wood density value in the latewood of a tree ring, has been shown to closely follow summer temperature in different conifer species, but not yet in Bristlecone pine. The gnarly and twisted growth of these ancient trees has presented significant hurdles for MXD analysis. Here we apply an X‐ray Computed Tomography toolchain that allows us to 3D scan through the tissue of a tree ring and to map MXD variations. Using this new technique, we were able to reconstruct warm‐season temperature for the American Southwest back to 1625 CE. With these findings, we are confident that a full‐length reconstruction (back to 2575 BCE) can yield the longest annually resolved temperature reconstruction for this continent. Key Points: We present the first X‐ray Computed Tomography‐derived maximum latewood density‐based temperature reconstruction using Bristlecone pine tree coresBristlecone pine maximum latewood density is a reliable proxy for warm‐season temperature over a large part of the American SouthwestOur reconstruction (1625–2005 CE) contains low‐frequency variability and can be prolonged over a large part of the Holocene [ABSTRACT FROM AUTHOR]

Purpose: Wood comprises different cell types, such as fibers, tracheids and vessels, defining its properties. Studying cells' shape, size, and arrangement in microscopy images is crucial for understanding wood characteristics. Typically, this involves macerating (soaking) samples in a solution to separate cells, then spreading them on slides for imaging with a microscope that covers a wide area, capturing thousands of cells. However, these cells often cluster and overlap in images, making the segmentation difficult and time-consuming using standard image-processing methods. Results: In this work, we developed an automatic deep learning segmentation approach that utilizes the one-stage YOLOv8 model for fast and accurate segmentation and characterization of macerated fiber and vessel form aspen trees in microscopy images. The model can analyze 32,640 x 25,920 pixels images and demonstrate effective cell detection and segmentation, achieving a mAP 0.5 - 0.95 of 78 %. To assess the model's robustness, we examined fibers from a genetically modified tree line known for longer fibers. The outcomes were comparable to previous manual measurements. Additionally, we created a user-friendly web application for image analysis and provided the code for use on Google Colab. Conclusion: By leveraging YOLOv8's advances, this work provides a deep learning solution to enable efficient quantification and analysis of wood cells suitable for practical applications. [ABSTRACT FROM AUTHOR]

Background: Wood carbon fractions (CFs)—the proportion of dry woody biomass comprised of elemental carbon (C)—are a key component of forest C estimation protocols and studies. Traditionally, a wood CF of 50% has been assumed in forest C estimation protocols, but recent studies have specifically quantified differences in wood CFs across several different forest biomes and taxonomic divisions, negating the need for generic wood CF assumptions. The Intergovernmental Panel on Climate Change (IPCC), in its 2006 "Guidelines for National Greenhouse Gas Inventories", published its own multitiered system of protocols for estimating forest C stocks, which included wood CFs that (1) were based on the best available literature (at the time) and (2) represented a significant improvement over the generic 50% wood CF assumption. However, a considerable number of new studies on wood CFs have been published since 2006, providing more accurate, robust, and spatially- and taxonomically- specific wood CFs for use in forest C estimation. Main text: We argue that the IPCC's recommended wood CFs and those in many other forest C estimation models and protocols (1) differ substantially from, and are less robust than, wood CFs derived from recently published data-rich studies; and (2) may lead to nontrivial errors in forest C estimates, particularly for countries that rely heavily on Tier 1 forest C methods and protocols (e.g., countries of the Global South with large expanses of tropical forests). Based on previous studies on this topic, we propose an alternative set of refined wood CFs for use in multiscale forest C estimation, and propose a novel decision-making framework for integrating species- and location-specific wood CFs into forest C estimation models. Conclusion: The refined wood CFs that we present in this commentary may be used by the IPCC to update its recommended wood CFs for use in forest C estimation. Additionally, we propose a novel decision-making framework for integrating data-driven wood CFs into a wider suite of multitiered forest C estimation protocols, models, and studies. [ABSTRACT FROM AUTHOR]

In situ reconstructed anti-corrosive and active surface on hierarchically porous carbonized wood for efficient overall seawater electrolysis. [Display omitted] [ABSTRACT FROM AUTHOR]

Summary: Wood is resulted from the radial growth paced by the division and differentiation of vascular cambium cells in woody plants, and phytohormones play important roles in cambium activity.Here, we identified that PagJAZ5, a key negative regulator of jasmonate (JA) signaling, plays important roles in enhancing cambium cell division and differentiation by mediating cytokinin signaling in poplar 84K (Populus alba × Populus glandulosa).PagJAZ5 is preferentially expressed in developing phloem and cambium, weakly in developing xylem cells. Overexpression (OE) of PagJAZ5m (insensitive to JA) increased cambium activity and xylem differentiation, while jaz mutants showed opposite results. Transcriptome analyses revealed that cytokinin oxidase/dehydrogenase (CKXs) and type‐A response regulators (RRs) were downregulated in PagJAZ5m OE plants. The bioactive cytokinins were significantly increased in PagJAZ5m overexpressing plants and decreased in jaz5 mutants, compared with that in 84K plants. The PagJAZ5 directly interact with PagMYC2a/b and PagWOX4b. Further, we found that the PagRR5 is regulated by PagMYC2a and PagWOX4b and involved in the regulation of xylem development.Our results showed that PagJAZ5 can increase cambium activity and promote xylem differentiation through modulating cytokinin level and type‐A RR during wood formation in poplar. [ABSTRACT FROM AUTHOR]

This study aimed to determine the effects of production parameters such as wood species and timber strength classes on some mechanical properties of CLT panels using both non-destructive and destructive methods. Additionally, the study compared the strength values obtained from non-destructive and destructive testing methods on CLT panels and elucidated the relationship between them through regression analyses. CLT panels were produced using spruce and alder timbers, as well as hybrid panels formed from combinations of these two wood species. According to the TS EN 338 standard, the C and D strength classes of the timbers were determined non-destructively using an acoustic testing device. Among the timbers whose strength classes were determined, a total of 6 different strength classes were selected for spruce and alder. The bending strength, modulus of elasticity, and screw withdrawal force tests were performed on the CLT panel groups both non-destructive and destructive. As a result of the regression analyzes, the determination coefficient (R2) between non-destructive screw withdrawal force and destructive bending strength values varied between 0.6135–0,9997. Moreover, the R2 value calculated between non-destructive and destructive modulus of elasticity values for CLT panels was found to be between 0.7076–0.9997. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the performance and factors affecting the species classification of convolutional neural network (CNN) architecture using whole-part and earlywood-part cross-sectional datasets of six Korean Quercus species. The accuracy of species classification for each condition was analyzed using the datasets, data augmentation, and optimizers—stochastic gradient descent (SGD), adaptive moment estimation (Adam), and root mean square propagation (RMSProp)—based on a CNN architecture with three to four convolutional layers. The model trained with the augmented dataset yielded significantly superior results in terms of classification accuracy compared to the model trained with the non-augmented dataset. The augmented dataset was the only factor affecting classification accuracy in the final five epochs. In contrast, four factors in the entire epoch, such as the Adam and SGD optimizers and the earlywood-part and whole-part datasets, affected species classification. The arrangement of earlywood vessels, broad rays, and axial parenchyma was identified as a major influential factor in the CNN species classification using gradient-weighted class activation mapping (Grad-CAM) analysis. The augmented whole-part dataset with the Adam optimizer achieved the highest classification accuracy of 85.7% during the final five epochs of the test phase. [ABSTRACT FROM AUTHOR]

Cryptotermes brevis (Walker) (Blattodea: Kalotermitidae) is one of the most destructive drywood termites that attack moisture‐protected timber in service. Heat treatment has been studied to control these termites, but the low thermal conductivity of wood can result in prolonged treatment times and the need for high temperatures to eliminate termite colonies. The current study investigated heat transfer through a heat transfer model and experiments within solid timber boards and a representative wall section. The aim was to optimise targeted spot heat treatment as a cost‐effective method for eradicating this pest within structural elements. Through experimental work and the development of a deterministic heat transfer model, valuable insights were gained into temperature distribution within wooden structural elements. The findings revealed that proximity to the heated surface played a crucial role, with closer distances reaching equilibrium temperatures faster. The heat transfer model, validated against experimental data, accurately predicted temperature distributions within the timber. Termite survival was significantly influenced by heating time and distance from the heated surface when a wall section was heated at 60°C. The mean survival of C. brevis pseudergates kept inside wall studs varied from 30% to 96.7% depending on the distance from the heated surface after 1.5 h of heating, where the temperature ranged from 43°C to 45°C. However, after extending the heating duration to 3 h, the temperature in wall studs was elevated to 51°C, 49°C and 47°C at 22, 40 and 60 mm from the heated stud face, respectively. All C. brevis pseudergates across all distances were killed at a 3‐h duration. This research underscores the importance of understanding temperature distribution in structural wood elements and exposure times when employing heat as a spot treatment for drywood termite control. [ABSTRACT FROM AUTHOR]

Background Objectives Results Conclusions The woods of trees of the genus Dalbergia are a frequent cause of allergic contact dermatitis.To describe the different patterns of symptoms and sensitisation to woods of the genus Dalbergia in four patients whose regular work is linked to music, either as performers (two patients) or instrument makers.The patients showed extensive cross‐reactivity between the different Dalbergia woods. The two musicians exhibited symptoms exclusively in the contact areas, while the instrument makers showed a pattern of airborne symptoms. The period from sensitisation to the development of symptoms varied greatly among the patients.The symptoms of allergic contact dermatitis to Dalbergia woods differ markedly depending on the route of contact. Cross‐reactivity between the woods of this genus is very wide. The sensitising potential varies between the various Dalbergia woods, which require different contact periods depending on their sensitising power. [ABSTRACT FROM AUTHOR]

The anatomical description of wood and charcoal for a wide variety of purposes is an essential tool for compiling databases to correctly identify species. This study describes and compares the anatomy of the wood and charcoal of Manilkara sp., collected in a protected area in the Pará state, Brazil. The qualitative anatomical characteristics of the wood, such as diffuse-porosity; vessels in radial multiples; alternate intervessel pits; axial parenchyma in lines or reticulate; rays uniseriate or biseriate, not storied, are corroborated in the literature. Moreover, this work reports the presence of helical thickenings in the vessel elements and possible helical thickenings in fibres in Manilkara. After the carbonization process, there were morphometric changes in the anatomical elements, as an increase in vessel frequency between 23 % and 141 %, and in ray frequency between 2.8 % and 12.9 %; while ray height decreased and ray width increased. Overall, some anatomical variations could be related to, or a result of the interaction between species plasticity, genetics, age and environmental factors. These characteristics enabled the identification of the samples at the genus level and the anatomical description of the wood and charcoal can be useful for forest inspections. [ABSTRACT FROM AUTHOR]

AbstractA general solution technique for hygrothermo-electroelastic problems in bodies with D∞ symmetry is developed. The displacement and electric field are expressed in terms of their respective potential functions, and the hygrothermo-electroelastic field quantities are expressed in terms of elastic and piezoelastic potential functions, each of which satisfies a Laplace equation with respect to the appropriately transformed spatial coordinates, combined with the two hygrothermoelastic displacement potential functions. As an application of this technique, a theoretical analysis of an infinite cylinder subjected to distributions of moisture content, temperature, and stress was performed, and the significance of the hygrothermo-electroelastic analyses was demonstrated. [ABSTRACT FROM AUTHOR]

The checkerboard constitutes the best pattern for full‐field strain measurement because it maximizes image gradient. In the experimental mechanics community, employing this pattern is currently strongly limited because depositing it on the surface of specimens raises practical difficulties. A recent study shows, however, that it is technically possible by using a laser engraver. The present paper aims to push this solution forward by printing a checkerboard pattern on a thin polymeric film and then gluing the resulting laser‐engraved film on the specimen surface. The underlying idea is to separate the manufacturing process of this optical strain gauge on the one hand and its use on the other hand to help spread this strain measuring tool in the experimental mechanics community. The polymeric film employed here is the same as that used in the manufacturing process of classic electrical gauges, so one can rely on the know‐how of classic strain gauge bonding to glue this optical strain gauge on the specimen surface. The main difference between the proposed tool and classic electrical gauges is that the strain field beneath the polymeric support is measured instead of localized strain values. The paper is a proof of concept for this strain field measuring tool. The manufacturing and bonding processes are described in the paper. The localized spectrum analysis, a spectral technique developed for processing images of periodic patterns, is used to retrieve the strain fields from checkerboard images. Through two complementary examples, we show the ability of this new type of strain gauge to detect and quantify local details in the strain field beneath. A simplified 1D model is also proposed to assess the minimum width of the strain peak that can reliably be measured with this technique. [ABSTRACT FROM AUTHOR]

As major terrestrial carbon sinks, forests play an important role in mitigating climate change. The relationship between the seasonal uptake of carbon and its allocation to woody biomass remains poorly understood, leaving a significant gap in our capacity to predict carbon sequestration by forests. Here, we compare the intra-annual dynamics of carbon fluxes and wood formation across the Northern hemisphere, from carbon assimilation and the formation of non-structural carbon compounds to their incorporation in woody tissues. We show temporally coupled seasonal peaks of carbon assimilation (GPP) and wood cell differentiation, while the two processes are substantially decoupled during off-peak periods. Peaks of cambial activity occur substantially earlier compared to GPP, suggesting the buffer role of non-structural carbohydrates between the processes of carbon assimilation and allocation to wood. Our findings suggest that high-resolution seasonal data of ecosystem carbon fluxes, wood formation and the associated physiological processes may reduce uncertainties in carbon source-sink relationships at different spatial scales, from stand to ecosystem levels. Forest carbon source and sink processes may have contrasting climatic sensitivities. This analysis on 177 coniferous forest sites shows that carbon fluxes and wood formation are coupled but not fully synchronous at intra-annual scales, with peaks in cambial activity preceding those in photosynthesis and respiration. [ABSTRACT FROM AUTHOR]

OBJECTIVE To retrospectively report the historical and clinical findings, diagnostics, treatment, and outcome of horses with penetrating wood foreign bodies (PWFBs) of the coronary band. ANIMALS 15 client-owned horses. CLINICAL PRESENTATION Horses had varying degrees of lameness and soft tissue swelling of the coronary band and pastern region. A defect in the coronary band was identified, but the actual wood foreign body was not always readily visualized. RESULTS Medical records of horses diagnosed with PWFBs of the coronary band between 2004 and 2023 were reviewed. Information retrieved from the medical records included history, signalment, diagnostics, treatment, and outcome. Thirteen of 15 horses that sustained a PWFB to the coronary band were participating in foxhunting. Penetrating wood foreign bodies occurred more frequently near the central axis or toe region (11/15) and more commonly in the forelimbs (11/15). Removal of PWFBs can be performed with the horse standing and sedated with regional anesthesia. Complete removal of the PWFB required partial removal of the adjacent hoof wall. CLINICAL RELEVANCE Penetrating wood foreign bodies occurred in the coronary band and lodged distally in the hoof wall of horses. Foxhunting may be a risk factor for this type of injury. Penetrating wood foreign bodies occurred most commonly in the front feet, near the central axis of the coronary band. Complete removal of the PWFB required removing a section of the adjacent hoof wall. The prognosis for return to the previous level of activity following treatment was favorable. [ABSTRACT FROM AUTHOR]

The biosynthesis of cellulose, lignin, and hemicelluloses in plant secondary cell walls (SCWs) is regulated by a hierarchical transcriptional regulatory network. This network features orthologous transcription factors shared between poplar and Arabidopsis, highlighting a foundational similarity in their genetic regulation. However, knowledge on the discrepant behavior of the transcriptional‐level molecular regulatory mechanisms between poplar and Arabidopsis remains limited. In this study, we investigated the function of PagMYB128 during wood formation and found it had broader impacts on SCW formation compared to its Arabidopsis ortholog, AtMYB103. Transgenic poplar trees overexpressing PagMYB128 exhibited significantly enhanced xylem development, with fiber cells and vessels displaying thicker walls, and an increase in the levels of cellulose, lignin, and hemicelluloses in the wood. In contrast, plants with dominant repression of PagMYB128 demonstrated the opposite phenotypes. RNA sequencing and reverse transcription – quantitative polymerase chain reaction showed that PagMYB128 could activate SCW biosynthetic gene expression, and chromatin immunoprecipitation along with yeast one‐hybrid, and effector–reporter assays showed this regulation was direct. Further analysis revealed that PagSND1 (SECONDARY WALL‐ASSOCIATED NAC‐DOMAIN PROTEIN1) directly regulates PagMYB128 but not cell wall metabolic genes, highlighting the pivotal role of PagMYB128 in the SND1‐driven regulatory network for wood development, thereby creating a feedforward loop in SCW biosynthesis. [ABSTRACT FROM AUTHOR]

Modeling of moisture transfer in porous materials is typically partitioned into liquid transport and vapor diffusion. Coefficients for liquid transport are often derived from laboratory measurements of water absorption by partial immersion. Although the assumption that capillary liquid transport is dominant while vapor diffusion is negligible is a reasonable assumption for mineral-based materials, recent work indicates that it is not representative of water absorption in wood across the grain. This article builds on earlier work and develops an improved engineering model for liquid water transport in softwoods. The approach uses a constant liquid diffusivity value, relies primarily on ordinary hygrothermal property measurements, and partitions vapor and liquid transport in a practical way that is informed by current understanding of wood–water interactions. The model is optimized using one-dimensional simulations calibrated against measured water uptake across a range of softwood species. Laboratory measurements were conducted to investigate key properties of eastern white cedar, which had the highest relative error in a previous version of the model, and to examine the practicality and relevance of vacuum saturation and free saturation for southern yellow pine. The model accuracy is improved by paying closer attention to the moisture storage function and capillary saturation value. [ABSTRACT FROM AUTHOR]

In this study we quantify wood flows from raw materials to end‐uses for the United Kingdom in a robust way using a new material flow analysis (MFA) model with uncertainty. This is important to identify opportunities for efficiency given constraints on wood supply. We have developed a new "ProbPACTOT" MFA model which introduces a systematic method to handle mixed units during reconciliation and uncertainty in data observations, conversion factors, and process recipes. This makes it possible to track material flows all the way to end‐uses, which is otherwise difficult because the diverse materials, data types, and units used to quantify end‐products are hard to integrate into standard allocation‐based MFA models. We apply the model for the case of wood in the United Kingdom by defining 56 process recipes and reconciling 117 data observations from various sources. The results quantify upstream production and trade flows, through to 19 specific end‐uses of wood fibers. We use this to show the potential scale of savings by enhancing material efficiency; for example, if pallets were used 25% more intensively, 0.49 ±$\pm$0.2 Mm3${\rm M}\mathrm{m^3}$ of wood fibers could be saved, corresponding to 4%–7% of the total soft sawnwood consumption of the United Kingdom. Judging the scale of opportunities for wood material efficiency in the United Kingdom is important domestically, and has global significance as the United Kingdom is the second largest net importer of wood products in the world. Moreover, this study proposes an important advancement in MFA giving a structure for modeling uncertain material flows up to end‐uses, applicable to any material. This article met the requirements for a gold‐gold JIE data openness badge described at http://jie.click/badges. [ABSTRACT FROM AUTHOR]

Improving the durability of short-rotation wood can be achieved through chemical and thermal modification. Chemical and thermal modification can have an impact on the physicochemical properties of wood, which can affect wood's surface characteristics and its resistance to weathering. The purpose of this study was to investigate the surface characteristics and artificial weathering resistance of chemically and thermally modified short-rotation teak wood coated with linseed oil (LO)-, tung oil (TO)-, and commercial oil-based coatings consisting of a mixture of linseed oil and tung oil (LT) and commercial oil-based polyurethane resin (LB) coatings. The short-rotation teak woods were prepared in untreated and treated with furfuryl alcohol (FA), thermal treatment (HT) at 150 and 220 °C, and combination of glycerol–maleic anhydride (GMA) impregnation with thermal treatment at 150 and 220 °C. The surface characteristics measured were surface free energy, wettability, Persoz hardness, bonding quality, and color changes before and after artificial weathering exposure. The results showed that chemical and thermal modifications treatment tended to reduce total surface free energy (SFE), hardness, wettability, and bonding quality. FA and GMA at 220 °C treatments provided homogenization effect on surface characteristics, especially in total SFE and wettability. The total SFE of untreated wood ranged from 45.00 to 51.13 mN/m, and treated wood ranged from 40.58 to 50.79 mN/m. The wettability of oil-based coating according to K-value ranged from 0.20 to 0.54. TO presented better photostability than LO. Short-rotation teak wood coated with oil-based commercial coatings presented better weathering resistance compared to pure natural drying oil. Commercial oil-based coatings provided better weathering protection for the chemically and thermally modified teak wood. The application of oil-based coatings on chemically and thermally modified short-rotation teak is being considered for the development of a better wood-protection system. [ABSTRACT FROM AUTHOR]

Water vapor sorption is a fundamental property of cellulosic materials. Numerous theoretical and empirical models have been developed to describe the relationship between water activity, temperature, and equilibrium moisture content (EMC). However, a meaningful connection between model parameters and thermodynamic properties related to the sorption process is often lacking. In cases where models yield thermodynamic properties, such as through use of the Clausius-Clapeyron equation, these are limited to temperatures where the ideal gas equation is applicable. In this paper we advance a thermodynamic framework and formulate a new semi-empirical sorption model based on the differential Gibbs energy of sorption as a function of EMC and temperature, intended for high temperature applications such as steam drying or fire modeling. We refer to this as the Comprehensive Analytical Sorption Thermodynamic (CAST) model. It has six parameters, includes temperature explicitly, and is invertible. The CAST model includes analytical equations for the differential enthalpy of sorption, the differential entropy of sorption, and the integral heat of wetting. The model is evaluated using sorption data and calorimetric data over a range of temperatures from the wood science literature and compared with several existing models. Overall, the CAST model fits the experimental sorption and calorimetric data with higher accuracy than existing models. [ABSTRACT FROM AUTHOR]

Cellulose and lignin, sourced from biomass, hold potential for innovative bioprocesses and biomaterials. However, traditional fractionation and purification methods often rely on harmful chemicals and high temperatures, making these processes both hazardous and costly. This study introduces a sustainable approach for fractionating acacia wood, focusing on both cellulose and lignin extraction using a deep eutectic solvent (DES) composed of choline chloride (ChCl) and levulinic acid (LA). A design of experiment was employed for the optimization of the most relevant fractionation parameters: time and temperature. In the case of the lignin, both parameters were found to be significant variables in the fractionation process (p-values of 0.0128 and 0.0319 for time and temperature, respectively), with a positive influence. Likewise, in the cellulose case, time and temperature also demonstrated a positive effect, with p-values of 0.0103 and 0.028, respectively. An optimization study was finally conducted to determine the maximum fractionation yield of lignin and cellulose. The optimized conditions were found to be 15% (w/v) of the wood sample in 1:3 ChCl:LA under a treatment temperature of 160 °C for 8 h. The developed method was validated through repeatability and intermediate precision studies, which yielded a coefficient of variation lower than 5%. The recovery and reuse of DES were successfully evaluated, revealing remarkable fractionation yields even after five cycles. This work demonstrates the feasibility of selectively extracting lignin and cellulose from woody biomass using a sustainable solvent, thus paving the way for valorization of invasive species biomass. [ABSTRACT FROM AUTHOR]

The actual study is the description of the biochemical characteristics of a wide range of enzymes (phenylalanine ammonia lyase, superoxide dismutase, catalase, peroxidase, polyphenol oxidase) and metabolites (malondialdehyde, phenols, extractives, cellulose, lignin), as well as the profiles of their activities during the xylem structural elements' formation during the predominance of differentiation processes during straight-grained wood formation or proliferation while the figured wood formation in the radial row cambial zone (Fraction 1)—differentiating xylem (Fraction 2)—mature xylem (MX) in the period of active cambial growth in 16-year-old straight-grained Betula pendula var. pendula and figured Betula pendula var. carelica plants. We generalized the processes associated with abnormal xylogenesis were separated spatially, and, to the greatest extent, the metabolism of the studied birch forms differed in the Fraction 2, while the diagnostic contribution of secondary metabolism enzymes and malondialdehyde (MDA) probably characterized the active secondary metabolism of parenchyma cells, which formed figured wood basis. This study described for the first time the biochemical features of a wide range of enzymes and metabolites as well as the profiles of their activities in the xylem structural elements' formation. The necessity of separately analyzing all tissue complexes was proven. This approach made possible to separate the generally observed biochemical patterns spatially. Thus, during the active cambial growth period in 16-year-old B. pendula var. pendula and B. pendula var. carelica, the differences between straight-grained plants and Karelian birch plants (non-figured and figured trunk parts) were most clearly expressed in the differentiating xylem. [ABSTRACT FROM AUTHOR]

The prevalent use of unsustainable polymers in current X‐ray scintillators poses a significant environmental concern. The advancement of biodegradable X‐ray scintillators holds promise in mitigating escalating environmental issues tied to electronic or medical waste and carbon footprints. Herein, a biodegradable and flexible X‐ray scintillation film is presented employing lead‐free 0D Cs3Cu2I5 perovskite nanoparticles integrated into densified‐delignified wood (Cs3Cu2I5@D‐Wood). The Cs3Cu2I5@D‐Wood film demonstrates precise and detailed X‐ray imaging capabilities, achieving a high spatial resolution of 10 line pairs per millimeter (lp·mm−1). To minimize the environmental impact associated with disposal, metal and halide ions (e.g., Cs+, Cu+, I−) from Cs3Cu2I5@D‐Wood can be easily retrieved by a simple solvent extraction process. The approach showcases the potential of biodegradable wood‐based X‐ray scintillation screens as alternatives to conventional, plastic‐based screens. This offers a significant contribution to environmental sustainability by reducing electronic or medical waste. [ABSTRACT FROM AUTHOR]

Blends of prevulcanized natural rubber (PVNR) and acrylic emulsion (AC) were prepared at the fixed PVNR/AC ratio of 30/70. Effects of titanium dioxide (TiO2) addition were optimized across the contents 0, 10, 20 and 30 parts per hundred parts of polymer (php) with respect to various properties. Morphological analysis revealed a two-phase system in which the PVNR particles were dispersed in the AC matrix. Incorporation of TiO2 induced a finer blend morphology in which a part of the TiO2 was located at the interfaces of blend components. The tensile strength increased with initial TiO2 loading and reached its maximum at 10 php loading, with an improvement by about 127% over the blend without filler. However, further increase in filler loading reduced the tensile strength, and the filler tended to agglomerate at those higher loadings. Thermal stability and storage modulus in rubbery region of the blends containing TiO2 were also improved over the unfilled blend, due to the improved morphology and the hydrogen bonds between TiO2 filler and polymer matrix. TiO2 improved water wettability and adhesion of the blend. The maximum peel strengths on wood and metal substrates were about 120% and 26% larger than for the reference unfilled blend. Such drastic improvements suggest that the filled blends may find applications as coating materials. [ABSTRACT FROM AUTHOR]

Fungi are key decomposers of deadwood, but the impact of anthropogenic changes in nutrients and temperature on fungal community and its consequences for wood microbial respiration are not well understood. Here, we examined how nitrogen and phosphorus additions (field experiment) and warming (laboratory experiment) together influence fungal composition and microbial respiration from decomposing wood of angiosperms and gymnosperms in a subtropical forest. Nutrient additions significantly increased wood microbial respiration via fungal composition, but effects varied with nutrient types and taxonomic groups. Specifically, phosphorus addition significantly increased wood microbial respiration (65%) through decreased acid phosphatase activity and increased abundance of fast‐decaying fungi (e.g., white rot), while nitrogen addition marginally increased it (30%). Phosphorus addition caused a greater increase in microbial respiration in gymnosperms than in angiosperms (83.3% vs. 46.9%), which was associated with an increase in Basidiomycota:Ascomycota operational taxonomic unit abundance in gymnosperms but a decrease in angiosperms. The temperature dependencies of microbial respiration were remarkably constant across nutrient levels, consistent with metabolic scaling theory hypotheses. This is because there was no significant interaction between temperature and wood phosphorus availability or fungal composition, or the interaction among the three factors. Our results highlight the key role of tree identity in regulating nutrient response of wood microbial respiration through controlling fungal composition. Given that the range of angiosperm species may expand under climate warming and forest management, our data suggest that expansion will decrease nutrient effects on forest carbon cycling in forests previously dominated by gymnosperm species. [ABSTRACT FROM AUTHOR]

This paper presents a comparative analysis of the blind test outcomes of two independent methods for the identification of tropical wood species in pulp and paper products. Both, the established anatomical and the relatively new chemotaxonomic method support the European Deforestation Regulation 2023/1115 (EUDR), which aims to ensure that only legally harvested timber that has not contributed to deforestation is traded in the EU. The blind test involved 570 decisions on 15 test sheets of 37 self-manufactured mixed tropical hardwood pulps and an industrial beech pulp, used as a matrix. Both detection techniques demonstrated robust performance with over 80 % hit rates. The results show that the synergies and combination of the strengths of both methods can be utilized and lead to even better combined performance. In order to establish the chemotaxonomic identification method as a complement to the conventional anatomy-based method, statistical analyses were performed to assess its intermediate precision between three different GC-MS systems. In most cases, the method gave consistent results independent of the instrument used. [ABSTRACT FROM AUTHOR]

Aim Location Time period Major taxa studied Methods Results Main conclusions Changes in climate are likely to have major impacts on benefits (i.e., biodiversity and ecosystem services) supported by trees. Here we explore the extent to which trees can support multiple benefits, and the potential tradeoffs among them, under increasing dryness.Eastern Australia.2018–2019.Trees.We evaluated changes in biodiversity and services supported by trees and the nature of potential tradeoffs in response to increasing aridity, our proxy of drying regional climates. We assessed six benefits (biodiversity and five ecosystem services) supported by trees at 126 sites across a gradient from Australia's mesic coast to the arid interior.The value of average benefits did not vary with aridity, with winners and losers in biodiversity and ecosystem services as aridity intensified. Tradeoffs between biodiversity and soil stability declined with increasing aridity, but only in mesic environments, whereas tradeoffs between wood production potential and carbon storage intensified under greater aridity levels, but only in mesic environments. Aridity and tree structure were the major regulators of these tradeoffs, particularly under dry environments. Increasing aridity affected tradeoffs directly or indirectly by either suppressing the positive effect of tree height or exacerbating the negative effect of tree canopy size.Our results indicate that biodiversity and most ecosystem services supported by trees are likely to decline under future climate change scenarios and demonstrate the importance of targeting afforestation programs to specific services in particular climatic areas rather than attempting to improve multiple services. [ABSTRACT FROM AUTHOR]

ABSTRACT The aroma of fine matured spirits is typically complex, resulting from numerous reactions occurring during the production process and some developing during maturation in oak casks. The refreshing sensation brought by mint notes was often expected, even after years of maturation. The main challenge lies in achieving an aromatic balance characterised by the seamless integration of woody aromas while maintaining the initial distillate's freshness. The present study examines the sensory effects associated with the interactions between wood, mint and cold sensations in spirits. Nine spirit model solutions were prepared, representing different combinations of terpene ketones (imparting mint aroma) and wood compounds, each at three concentration levels. The quantitative composition of mint compounds simulated varying degrees of mintiness in the distillate (low, medium and high), while the concentrations of wood compounds mimicked three maturation periods (short, intermediate and long term) in wooden casks. Samples were sensorily analysed by discriminative (triangle test) and rate‐all‐that‐apply (RATA) methodologies. An increase in woody intensity was notably perceived in samples with a low‐mint profile and containing wood compounds associated with medium and long‐term maturation. However, no significant sensory differences were observed in mint and cold perception between model solutions regardless of the simulated maturation conditions, indicating a limited influence of the studied wood compounds on the sensation of freshness in spirits due to competitive perceptual interactions with terpene ketones. [ABSTRACT FROM AUTHOR]

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. Increasing shortages and costs of common bedding materials have led dairy farmers in Sweden to consider using recycled manure solids (RMS), which are readily available and low cost, as an alternative bedding material. The main risks are effects on udder health and milk quality, but RMS could also affect animal welfare and claw health. The advantages and disadvantages of using RMS bedding have not been fully investigated, and findings in other countries cannot be directly applied to Swedish conditions and climate. This observational cross-sectional study investigated the use of RMS as bedding, regarding associations with certain aspects of animal welfare, herd health, milk quality, and bedding costs in Swedish dairy herds. Thirty-four dairy farms using RMS or wood shavings/sawdust (each n = 17) were compared. Each farm was visited 2 times during the housing period from 2020 to 2021, once from October to December and once from March to May. Dairy barns were observed, animal welfare was assessed, and freestall dimensions were measured. Farm owners were interviewed about housing system characteristics, herd performance, and herd management. Data on milk production and herd health were obtained from the Swedish official milk recording scheme for the indoor period from October to March. The prevalence of claw disorders and abnormal claw conformation were collected from the national claw health database for the period from October to May. On each farm visit, composite samples of unused bedding outside the barn and used bedding material from the freestalls, respectively, were taken for total bacterial count and DM analysis. Samples of bulk tank milk for determination of total bacterial count were taken in connection to the visits. In addition, samples of unused and used bedding material and manure from alleys for analysis of 3 Treponema species associated with digital dermatitis (DD) were gathered and analyzed. Total bacterial count was significantly higher in unused (8.50 log 10 cfu/g) and used RMS bedding (9.75 log 10 cfu/g) than in wood shavings/sawdust (used 4.74; unused 8.63 log 10 cfu/g), but there were no significant differences in bulk milk total bacterial count (median 4.07 vs. 3.89 log 10 cfu/mL) or SCC (median 243,800 vs. 229,200 cells/mL). The aspects of animal welfare assessed did not differ significantly between the 2 bedding systems, whereas the prevalence of total claw disorders (25.9% vs. 38.0% of trimmed cows), dermatitis (6.9% vs. 16.2% of trimmed cows) and sole ulcers (2.0% vs. 4.0% of trimmed cows) were significantly lower in the RMS herds. Treponema spp. were not detected in unused RMS material, but all RMS herds had presence of DD recorded at foot trimming. An economic assessment based on the interview results and price level from winter 2021 revealed that the costs of RMS bedding varied with amount of RMS produced. Thus, RMS is a potential alternative bedding material for dairy cows in Sweden and can be a profitable option for large dairy herds. However, the high level of total bacteria in the material requires attention to bedding and milking routines as well as regular monitoring of herd health. [ABSTRACT FROM AUTHOR]

Summary: Wood formation, which occurs mainly through secondary xylem development, is important not only for supplying raw material for the 'ligno‐chemical' industry but also for driving the storage of carbon. However, the complex mechanisms underlying the promotion of xylem formation remain to be elucidated. Here, we found that overexpression of Auxin‐Regulated Gene involved in Organ Size (ARGOS) in hybrid poplar 84 K (Populus alba × Populus tremula var. glandulosa) enlarged organ size. In particular, PagARGOS promoted secondary growth of stems with increased xylem formation. To gain further insight into how PagARGOS regulates xylem development, we further carried out yeast two‐hybrid screening and identified that the auxin transporter WALLS ARE THIN1 (WAT1) interacts with PagARGOS. Overexpression of PagARGOS up‐regulated WAT1, activating a downstream auxin response promoting cambial cell division and xylem differentiation for wood formation. Moreover, overexpressing PagARGOS caused not only higher wood yield but also lower lignin content compared with wild‐type controls. PagARGOS is therefore a potential candidate gene for engineering fast‐growing and low‐lignin trees with improved biomass production. [ABSTRACT FROM AUTHOR]

This study evaluated two fundamental assumptions about the geometry of the wood cell wall to develop a mechanistic characterization of wood behavior at the scale of wood structural components. This paper used a three-step homogenization scheme implemented through homogenization techniques and finite-element analyses to evaluate a multilayered cell wall and a simplified single-layer method. Both earlywood and latewood geometries were considered. A three-part sensitivity analysis assessed the influence of wood constituent proportions, microfibril angle, and cellulose crystallinity on cell wall stiffness. Sensitivity to constituent ratios was evaluated through a Monte Carlo simulation of 1,000 sampled points and correlation analysis. Sensitivity to microfibril angle and cellulose crystallinity was evaluated through parametric characterization. The investigation found that both methods provided an accurate assessment of wood stiffness when compared with experimentally determined values. Care should be taken when modeling higher densities of wood, and use of either method in higher order models should be determined by the resolution of input data and computational needs. [ABSTRACT FROM AUTHOR]

Sorption of water has a profound effect on the material properties of wood. The uptake of water vapour in wood and other materials releases more heat than the condensation of vapour to liquid water. This excess energy provides insights to the interactions and energy state of the absorbed water molecules. Modification of wood by acetylation is a common way of altering the wood-water interactions; however, very few data exist on how this and other types of modification affect the energy state of absorbed water in wood. This study is the first to use sorption calorimetry on modified wood to explore the effect of acetylation on wood-water interactions. Acetylation decreased the strength of the interactions between wood and water as seen from a decrease in differential enthalpy of mixing, both overall and in the dry state. It appears that acetylation removes or hinders the most-energetic interactions or bonding configurations of water in wood, perhaps because acetylation reduces the number of water-accessible hydroxyls more than it reduces the amount of absorbed water molecules. [ABSTRACT FROM AUTHOR]

The hydrothermal/soft templating method is an effective way to synthesize ordered mesoporous carbon (OMC), yet the mechanism of this strategy is not well illustrated. Herein, a hydrothermal temperature‐controlled approach is developed to precisely synthesize OMCs with well‐defined morphologies from liquefied wood (LW). As the hydrothermal temperature increases from 130 to 210°C, the hydrophilicity of the hydrophilic blocks decreases accompanied by the increase of the relative volume of the hydrophobic block, resulting in the packing parameter p of micelles changing from p ≤ 1/3 to 1/3 < p < 1/2, which transforms the micelle's structure from spherical to cylindrical. Additionally, accelerated nucleation occurred with the increased hydrothermal temperature. When the rate of nucleation is matched to the self‐assembly of the composite micelles, the composite micelles grow into worm‐like morphology and an ordered p6m mesostructure. This hydrothermal temperature‐controlled strategy provides a straightforward and effective approach for synthesizing OMCs with various morphologies from LW, addressing the previously insufficiently elucidated micelle formation mechanism in the hydrothermal/soft templating method. [ABSTRACT FROM AUTHOR]

Like many other anthropogenic habitats, log piles are mainly built in urban areas as a species-specific conservation measure for the European stag beetle (Lucanus cervus). As little is known about the success of this measure, we aim to study their success and longevity based on 100 small log piles that were followed up with emergence traps. Log piles were colonised the first year of building and beetles emerged up to 13 years later, with most beetles emerging after eight years. Overall, 67% of the log piles had emerging beetles: Quercus robur log piles (80%) were more successful than Fagus sylvatica (58%) and Populus x canadensis (50%). Overall, 177 ± 5, 131 ± 5 and 89 ± 5 beetles emerged per 1 m³ wood used in the log pile for oak, beech, and poplar respectively, but tree species had no effect on the size of the beetles. The emergence phenology was explained by a degree-day model with 6.6 °C as baseline temperature, predicting start and end of the emergence around 620 and 810 accumulated degree-days. Implications for insect conservation: We conclude that log piles are a successful conservation measure for the European stag beetle but distance to populations and abiotic characteristics need to be considered. For conserving this species in urban areas, we propose to build a network of log piles and to build new log piles about every ten years while retaining the old log piles. As the log piles are used by several species, they can also be useful for the conservation of other saproxylic species. [ABSTRACT FROM AUTHOR]

This study outlines a method of utilizing the finite element method and a simple mathematical model to predict the behavior of laminated veneer lumber (LVL) beams strengthened with composite sheets. The numerical models were created using the Abaqus 2017 software. The LVL was considered as a linearly elastic or elastic–plastic material, factoring in Hill's yield criterion. The composites were simulated as linearly elastic–ideally plastic materials. The mathematical models were predicated on the methodology of transformed cross-section. The theoretical and numerical outcomes were juxtaposed with previous empirical investigations. The comparison encompassed load-bearing capacity, stiffness, and deformation under peak force. Furthermore, presentations of normal stress maps in the LVL and composite have been illustrated. The derived maps were juxtaposed with the delineations of failure modes. An adequate correlation was identified between the theoretical, numerical, and empirical values in the case of beams reinforced with aramid, glass, and carbon sheets. The relative deviation varied from several to multiple percentages. This technique is not applicable for evaluating load-bearing capacity and deformation when only dealing with sheets with low elongation of rupture. This is a consequence of their premature failure. The proposed models may be utilized by researchers and engineers in the design of reinforcements for timber structures. [ABSTRACT FROM AUTHOR]

The pyrolysis by‐products of five common wood‐based construction materials (low‐density wood fiberboard, oriented strand board, pine, particle board, and plywood) were studied using pyrolysis‐gas chromatography/mass spectrometry. Samples of wood‐based materials were pyrolyzed under helium from 300 to 800°C to further understand the production of compounds that may become airborne and available for respiratory and dermal exposure. Benzene, toluene, ethylbenzene, p‐xylene, styrene, and naphthalene were specifically targeted since these compounds are common by‐products of pyrolysis. These compounds have been measured in previous live fire scenarios and are associated with human health concerns. The generated pyrolysates were separated and identified with a gas chromatography/mass spectrometry instrument. The results from total ion chromatograms and selected ion monitoring chromatograms were analyzed to compare the abundance of chemicals of interest generated during pyrolysis. Oriented strand board and plywood generated the greatest total concentration of the targeted volatile organic compounds. Plywood and particle boards generated the largest variety in results. Samples from solid pine boards generated the smallest number of volatile compounds, followed by low‐density wood fiberboard that is manufactured with wood fibers, starch, and wax. Notably, pyrolysis by‐products are not the sole compounds generated during the combustion of biomass and these products evolve when they are exposed to the conditions of combustion. Our future work plans to study the combustion by‐products of these materials. [ABSTRACT FROM AUTHOR]

With the increasing importance of wood as a sustainable material and addressing challenges facing the wood products industry, there is an emerging need for innovation and collaboration across all industry sectors. The mapping of the wood products industry has become crucial for gaining an overview and overall understanding of material flow. It also proved beneficial for educational and research purposes. The outcome of this study should help seek new economic opportunities and promote sustainable resource management. A Generic Map was developed to navigate the entire wood products industry as well as Dive-in Chain Maps will guide the four major production chains: sawmill (I), veneer mill (II), reconstituted wood manufacturing (III), and pulp and paper mills (IV). In addition, a By-products Management Wheel Diagram was introduced to clarify waste management practices within these chains. Our approach sheds light on efficient material flow and utilization, revealing opportunities for innovation and the development of high-value products. It also offers strategies for minimizing waste and making informed end-of-life decisions. Ultimately, this study enhances the understanding and potential for circularity and sustainability in the wood products industry. [ABSTRACT FROM AUTHOR]

Wood, a fundamental material in construction, confronts durability and weathering challenges, notably UV-induced degradation leading to colour changes. This study investigated a novel treatment using citric acid and urea to enhance the UV stability of wood. The reaction between these compounds generates water-soluble fluorescent species and insoluble particles upon thermal treatment which may provide wood with UV protection. Specimens were treated with two different treatment methods and then exposed to 2016 h of accelerated weathering, during which colour was measured regularly. Citric acid and urea were either pressure impregnated into the wood and thermally reacted in situ during heat treatment or pre-reacted in the absence of wood with subsequent implementation into melamine formaldehyde (MF) and water-based surface coatings. The results showed that water-soluble fluorophore compounds were formed with both treatment methods. Accelerated weathering tests revealed significant colour changes over time, where specimens coated with a mixture of MF and fluorescent particles from the reaction between citric acid and urea, exhibiting the least alteration. The lowest colour change ΔE of 5.9 was observed for specimens coated with a MF-based coating containing 1 wt% of citric acid and urea thermally pre-reacted at a temperature of 180 °C, showcasing potential wood protection applications. [ABSTRACT FROM AUTHOR]

Wood branches subjected to bending develop reaction wood to accommodate both tensile and compressive stresses. For softwood, such as Norway spruce and Scots pine, compression wood (CW) develops in the lower parts, while opposite wood (OW) develops on the upper parts of the branch. It is likely that the ratio of CW to OW is optimised for mechanical load bearing by nature. This hypothesis was tested with an analytical beam model using experimental data of stiffness and strength of CW and OW at CW fractions from 0 to 100%. It was found that there is indeed a maximum bending moment capacity around 35% CW, like literature values of CW content in softwood branches. For all compositions, compressive or tensile strength of OW was governing the behaviour. [ABSTRACT FROM AUTHOR]

The fungus Physisporinus vitreus and the bacterium Bacillus subtilis are commonly used organisms in wood biotechnology to increase wood permeability. However, comparative researches on wood destruction by these biological wood decomposers are scarce, particularly from microscopic and chemical perspectives. This study aimed to compare the fungal and bacterial wood destruction patterns over time. Loblolly pine (Pinus taeda L.) heartwood samples were exposed to both organisms for six and nine weeks; microscopic and spectroscopic analyses of the incubated wood were performed, and mass loss of samples was calculated. Both organisms initially destroyed the pit tori and ray parenchyma cells, but B. subtilis was more selective in its consumption of wood components. It exclusively consumed hemicelluloses and free carbohydrates in wood, whereas the fungus destroyed all chemical components simultaneously. The digestion of bordered pits by B. subtilis was more selective than that by P. vitreus, making it a better choice for controlled wood destruction. By extending the exposure duration, the bacterial destruction pattern remained consistent, whereas fungal destruction spread to the secondary wall of the tracheids. Understanding the interactions between microbes and wood can lead to a more effective and efficient use of this natural resource. [ABSTRACT FROM AUTHOR]

Considering that commonly occurring mold fungi have the ability to develop very quickly on the surface of wood chips and the ongoing studies on finding the ways to use degraded wood, the conducted research was aimed at determining the physical and mechanical properties of chipboards containing various amounts (0%, 30%, 50%, and 70%) of pine chips inoculated with Aspergillus and Penicillium fungi, varying in a degree of infestation. The inoculation did not cause significant changes in the chemical composition of chips; however, it caused a decrease in the pH of their surface after nine-week incubation. While using them, lowered pH caused a deterioration in the mechanical characteristics of the boards and increased their thickness swelling and water absorption. Moreover, no changes in density, formaldehyde content and decomposition by brown-rot fungi were found. Overall, it was concluded that the addition of partially infested chips did not significantly affect any properties of the board; however, in the case of complete overgrowth, the amount of degraded chips should be less than 30%. [ABSTRACT FROM AUTHOR]

The unassembled components of the Khufu-1 ship, dated to the mid-3rd millennium BC were found in 1954 just south of the Khufu pyramid in Egypt. It has two mid-sheer planks, one on each side: 23 m long, and a maximum of 40 cm wide and 14 cm thick. These planks were made from the cedar of Lebanon (Cedrus libani) imported from Lebanon, 320 Nautical Miles (600 km) away, along the eastern coast of the Mediterranean. According to scholars who studied this ship, the ship planks, which were curved in three dimensions, to fit the hull, were produced from the cedar trunk by carving, not by bending. Given that cedar wood was imported and expensive in Egypt, the choice of the carving technique was unexpected, and above all, would yield a plank weaker than one twisted and bent from a straight timber. The two production techniques (carving and bending) were compared, and it was found that bending was superior, and in fact, was demonstrated to be the actual method of shaping the planks of the Khufu-1 ship. [ABSTRACT FROM AUTHOR]

The study's objective was to assess the particle-size distribution and formulate an empirical model for the content of the finest dust created during the sanding of unmodified and thermally modified pine wood. The experimental design included unmodified and two options of thermally modified pine (Pinus sylvestris L.) wood samples, four feed speeds (3; 6; 9; 12 m·min−1), and three grit sizes of sanding belts (P60; P80; P100). The wood dust samples underwent sieve analysis to determine the particle-size distribution and laser analysis to determine the content of the finest particles. The sanding of thermally modified wood produced a higher amount of fine dust compared to unmodified wood. The content of fine dust increased with decreasing feed speed, while larger grit sizes resulted in increased production of fine dust. The average mass share of dust < 2.5, < 4, and < 10 µm was significantly lower when sanding the unmodified wood than thermally modified wood. The influence of feed speed, grit size, and material type on dust creation suggests that thermal modification is a factor in increasing the content of the potentially harmful finest particles (respirable fraction). The presented empirical model can help minimize health risks during the sanding of thermally modified pine wood by adjusting the sanding parameters. [ABSTRACT FROM AUTHOR]