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1.
J Theor Biol ; 579: 111718, 2024 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-38142855

RESUMEN

Data from the Danish milk recording system routinely enter the Danish Cattle Database, including somatic cell counts (SCC) for individual animals. Elevated SCC can signal intramammary inflammation, suggesting subclinical mastitis. Detecting mastitis is pivotal to limit severity, prevent pathogen spread, and target treatment or culling. This study aimed to differentiate normal and abnormal SCC patterns using recorded registry data. We used registry data from 2010 to 2020 for dairy cows in herds with 11 annual milk recordings. To create consistency across herds, we used data from 13,996 unique animals and eight different herds, selected based on the amount of data available, only selecting Holstein animals and conventional herds. We fitted log10-transformed SCC to days in milk (DIM) using the Wilmink and Wood's curve functions, originally developed for milk yield over the lactation. We used Nonlinear Least Square and Nonlinear Mixed Effect models to fit the log10-transformed SCC observations to DIM at animal level. Using mean squared residuals (MSR), we found a consistently better fit using a Wood's style function. Detection of MSR outliers in the model fitting process was used to identify animals with log10(SCC) curves deviating from the expected "normal" curve for that same animal. With this study, we propose a method to identify single animals with SCC patterns that indicate abnormalities, such as mastitis, based on registry data. This method could potentially lead to a registry data-based detection of mastitis cases in larger dairy herds.


Asunto(s)
Mastitis Bovina , Datos de Salud Recolectados Rutinariamente , Bovinos , Animales , Femenino , Humanos , Mastitis Bovina/diagnóstico , Mastitis Bovina/epidemiología , Industria Lechera/métodos , Lactancia , Leche , Recuento de Células/veterinaria , Glándulas Mamarias Animales
2.
Trop Anim Health Prod ; 56(3): 118, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38589528

RESUMEN

In field progeny testing program milk recording at monthly or bimonthly intervals and prediction of first lactation 305-day milk yield (FL305DMY) from these test day yields have been adapted as an alternative to daily milk recording. Wood's incomplete gamma function is the one of the commonly used nonlinear lactation curve model. In recent years Bayesian approach of fitting nonlinear biological models is gaining attention among researchers. In this study Wood's incomplete gamma function was fitted using Bayesian approach using monthly (MTDY) and bimonthly test day (BTDY) yields. The lactation curve parameters thus obtained were used for prediction of FL305DMY. Efficiency of prediction based on monthly and bimonthly test day milk yield were compared using error of prediction. It was found to be 5.78% and 7.59% as root mean square error (RMSE) based on MTDY and BTDY respectively.The Breeding values of 97 Karan Fries sires were estimated using BLUP-AM based on actual and predicted FL305DMY thus obtained. The RMSE was calculated as the difference between estimated breeding values based on actual and predicted yield. It was found that RMSE calculated based on MTDY showed only a marginal superiority of 0.79% over BTDY and showed high degree of correlation with actual yield. Therefore, recording at bimonthly intervals could be an economical alternative without compromising the efficiency.


Asunto(s)
Lactancia , Leche , Femenino , Bovinos , Animales , Teorema de Bayes , Dinámicas no Lineales
3.
Glob Chang Biol ; 29(11): 2968-2980, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36867108

RESUMEN

Climate models, and empirical observations, suggest that anthropogenic climate change is leading to changes in the occurrence and severity of extreme climatic events (ECEs). Effects of changes in mean climate on phenology, movement, and demography in animal and plant populations are well documented. In contrast, work exploring the impacts of ECEs on natural populations is less common, at least partially due to the challenges of obtaining sufficient data to study such rare events. Here, we assess the effect of changes in ECE patterns in a long-term study of great tits, near Oxford, over a 56-year period between 1965 and 2020. We document marked changes in the frequency of temperature ECEs, with cold ECEs being twice as frequent in the 1960s than at present, and hot ECEs being ~three times more frequent between 2010 and 2020 than in the 1960s. While the effect of single ECEs was generally quite small, we show that increased exposure to ECEs often reduces reproductive output, and that in some cases the effect of different types of ECE is synergistic. We further show that long-term temporal changes in phenology, resulting from phenotypic plasticity, lead to an elevated risk of exposure to low temperature ECEs early in reproduction, and hence suggest that changes in ECE exposure may act as a cost of plasticity. Overall, our analyses reveal a complex set of risks of exposure and effects as ECE patterns change and highlight the importance of considering responses to changes in both mean climate and extreme events. Patterns in exposure and effects of ECEs on natural populations remain underexplored and continued work will be vital to establish the impacts of ECEs on populations in a changing climate.


Asunto(s)
Passeriformes , Animales , Temperatura , Frío , Cambio Climático , Adaptación Fisiológica , Estaciones del Año
4.
Prog Oceanogr ; 218: 1-15, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-38269259

RESUMEN

Achieving gender equity is a long-standing and ubiquitous challenge in marine science. Creating equitable experiences for all genders in marine science requires recognizing scientists' intersectional identities, and how this leads to unique lived experiences of privilege and marginalization. One approach to increase equitable experiences for women in marine science is to create affinity groups where women can learn from each other, share their experiences, and provide support and mentorship. The Society for Women in Marine Science (SWMS) is one such organization, founded to amplify the work of early career women in marine science and create community, through events such as full-day symposium events. This study investigates the experiences of symposium attendees for four events held from 2018 through 2020, as reported in pre- and post-symposium surveys. We used quantitative analysis of the open-ended survey questions to examine the demographics of attendees and their fields of study. Qualitative thematic analysis identified the most effective aspects of the symposia, areas of logistical and content improvement for future symposia, and emphasized the unique challenges women in marine science experience. The majority of symposium attendees were white graduate students. Nearly all attendees identified as women, with a small number of men and non-binary individuals. Symposia attendees enjoyed opportunities for professional development and interactions with colleagues across career stages. We present recommendations for continuing to foster a sense of belonging in marine science and STEM more broadly, both specific to SWMS and transferable actions that can be applied for other affinity groups. These suggestions include empathetic event logistics, continual democratic evaluation, identity reflexivity among group leaders, and professional development activities targeted towards the unique needs of the affinity group. The positive responses received from SWMS's adaptive integration of survey results into symposia demonstrate that incorporating these recommendations and findings will help create an inclusive wave in marine science.

5.
Sensors (Basel) ; 23(11)2023 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-37299789

RESUMEN

Weak fault detection with stochastic resonance (SR) is distinct from conventional approaches in that it is a nonlinear optimal signal processing to transfer noise into the signal, resulting in a higher output SNR. Owing to this special characteristic of SR, this study develops a controlled symmetry with Woods-Saxon stochastic resonance (CSwWSSR) model based on the Woods-Saxon stochastic resonance (WSSR), where each parameter of the model may be modified to vary the potential structure. Then, the potential structure of the model is investigated in this paper, along with the mathematical analysis and experimental comparison to clarify the effect of each parameter on it. The CSwWSSR is a tri-stable stochastic resonance, but differs from others in that each of its three potential wells is controlled by different parameters. Moreover, the particle swarm optimization (PSO), which can quickly find the ideal parameter matching, is introduced to attain the optimal parameters of the CSwWSSR model. Fault diagnosis of simulation signals and bearings was carried out to confirm the viability of the proposed CSwWSSR model, and the results revealed that the CSwWSSR model is superior to its constituent models.


Asunto(s)
Algoritmos , Vibración , Simulación por Computador , Procesamiento de Señales Asistido por Computador , Ruido
6.
Environ Res ; 214(Pt 3): 113994, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35931185

RESUMEN

Atmospheric radiocarbon (14C) recorded in tree rings has been widely used for atmospheric 14C calibration purposes and climate studies. But atmospheric 14C records have been limited along tropical latitudes. Here we report a sequence from 1938 to 2007 of precisely measured 14C dates in tree rings of the parenchyma-rich Hymenolobium petraeum tree species (Porto Trombetas, 1°S, 56°W) from the Central Brazilian Amazon. H. petraeum has discernible growth ring boundaries that allow dating techniques to be employed to produce calendrical dates. Bomb-peak tree-ring 14C reconstruction coincides with the broader changes associated with reported values of the Southern Hemisphere atmospheric 14C curve (SH zone 3; values within the ±2σ interval), suggesting that inter-hemispheric air-mass transport of excess-14C injected into the stratosphere during intensive atmospheric nuclear tests is relatively uniform across distinct longitudinal regions. From the early 1980s onwards, H. petraeum had lower 14C values than other pantropical 14C records. Through 14C-based estimation, we found a strong influence of fossil-fuel CO2 contributions from Porto Trombetas mining operations and shipping traffic on inland waterways. An increase of at least 6.3 ± 0.8 ppm of fossil-fuel CO2 has been detected by 14C. Our findings invite further 14C analyses using tree rings of tropical tree species as a potential tracer for a wide range of environmental sources of atmospheric 14C-variability.


Asunto(s)
Bombas (Dispositivos Explosivos) , Combustibles Fósiles , Dióxido de Carbono/análisis , Clima , Minería
7.
Sensors (Basel) ; 22(14)2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35890993

RESUMEN

Scanning laser Doppler vibrometry is a widely adopted method to measure the full-field out-of-plane vibrational response of materials in view of detecting defects or estimating stiffness parameters. Recent technological developments have led to performant 3D scanning laser Doppler vibrometers, which give access to both out-of-plane and in-plane vibrational velocity components. In the present study, the effect of using (i) the in-plane component; (ii) the out-of-plane component; and (iii) both the in-plane and out-of-plane components of the recorded vibration velocity on the inverse determination of the stiffness parameters is studied. Input data were gathered from a series of numerical simulations using a finite element model (COMSOL), as well as from broadband experimental measurements by means of a 3D infrared scanning laser Doppler vibrometer. Various materials were studied, including carbon epoxy composite and wood materials. The full-field vibrational velocity response is converted to the frequency-wavenumber domain by means of Fourier transform, from which complex wavenumbers are extracted using the matrix pencil decomposition method. To infer the orthotropic elastic stiffness tensor, an inversion procedure is developed by coupling the semi-analytical finite element (SAFE) as a forward method to the particle swarm optimizer. It is shown that accounting for the in-plane velocity component leads to a more accurate and robust determination of the orthotropic elastic stiffness parameters.


Asunto(s)
Vibración
8.
J Hist Biol ; 54(2): 151-173, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33835368

RESUMEN

This article examines Chen Ziying, an American-trained Chinese biologist and his prewar efforts to bring his Woods Hole experience from the United States to China between 1930 and 1936. I argue that the Marine Biological Laboratory (MBL) appears as a prominent American scientific institution in the twentieth century among visiting Chinese students and scholars who were drawn to the American approach of building world-class seaside laboratories to facilitate marine biological study while cultivating a collaborative culture via songs of biology. Chen was one of the leading US-trained Chinese scientists who aspired to the international trend of developing coastal biology in the early twentieth century and was determined to modernize China's discipline-building of biology with the construction of marine research facilities similar to the MBL. I show that Chen's efforts of bringing the MBL practice to China took place at a time when science in China was overshadowed by the impulse of nationalism. Despite the nationalistic rhetoric, Chen was able to establish a Chinese connection with Woods Hole by introducing the MBL cultural practices of songs with biological significance. Lyrics from popular biological songs such as "It's a Long Way from Amphioxus" and "Songs of Amoy" reflect not just Darwinian themes but also a transnational connection between American and Chinese biologists in Republican-era China--a period in modern Chinese history that is often characterized by soaring sentiments of nationalism. This paper sets out to reconsider the interplay of scientific nationalism and scientific internationalism in shaping marine science in modern China, as well as to reflect on the meanings of value-laden terms such as "nationalism" and "foreignness" and their conceptual impacts on writing the historiography of biology in twentieth-century China.

9.
Molecules ; 25(6)2020 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-32214037

RESUMEN

Wood is one of the most highly valued materials in enology since the chemical composition and sensorial properties of wine change significantly when in contact with it. The need for wood in cooperage and the concern of enologists in their search for new materials to endow their wines with a special personality has generated interest in the use of other Quercus genus materials different from the traditional ones (Q. petraea, Q. robur and Q. alba) and even other wood genera. Thereby, species from same genera such as Q. pyrenaica Willd., Q. faginea Lam., Q. humboldtti Bonpl., Q. oocarpa Liebm., Q. stellata Wangenh, Q. frainetto Ten., Q. lyrata Walt., Q. bicolor Willd. and other genera such as Castanea sativa Mill. (chestnut), Robinia pseudoacacia L. (false acacia), Prunus avium L. and P. cereaus L. (cherry), Fraxinus excelsior L. (European ash) and F. americana L. (American ash) have been studied with the aim of discovering whether they could be a new reservoir of wood for cooperage. This review aims to summarize the characterization of tannin and low molecular weight phenol compositions of these alternative woods for enology in their different cooperage stages and compare them to traditional oak woods, as both are essential to proposing their use in cooperage for aging wine.


Asunto(s)
Fenoles/química , Quercus/química , Taninos/química , Madera/química , Peso Molecular
10.
Sensors (Basel) ; 18(4)2018 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-29671821

RESUMEN

The Centrifugal compressor is a piece of key equipment for petrochemical factories. As the core component of a compressor, the blades suffer periodic vibration and flow induced excitation mechanism, which will lead to the occurrence of crack defect. Moreover, the induced blade defect usually has a serious impact on the normal operation of compressors and the safety of operators. Therefore, an effective blade crack identification method is particularly important for the reliable operation of compressors. Conventional non-destructive testing and evaluation (NDT&E) methods can detect the blade defect effectively, however, the compressors should shut down during the testing process which is time-consuming and costly. In addition, it can be known these methods are not suitable for the long-term on-line condition monitoring and cannot identify the blade defect in time. Therefore, the effective on-line condition monitoring and weak defect identification method should be further studied and proposed. Considering the blade vibration information is difficult to measure directly, pressure sensors mounted on the casing are used to sample airflow pressure pulsation signal on-line near the rotating impeller for the purpose of monitoring the blade condition indirectly in this paper. A big problem is that the blade abnormal vibration amplitude induced by the crack is always small and this feature information will be much weaker in the pressure signal. Therefore, it is usually difficult to identify blade defect characteristic frequency embedded in pressure pulsation signal by general signal processing methods due to the weakness of the feature information and the interference of strong noise. In this paper, continuous wavelet transform (CWT) is used to pre-process the sampled signal first. Then, the method of bistable stochastic resonance (SR) based on Woods-Saxon and Gaussian (WSG) potential is applied to enhance the weak characteristic frequency contained in the pressure pulsation signal. Genetic algorithm (GA) is used to obtain optimal parameters for this SR system to improve its feature enhancement performance. The analysis result of experimental signal shows the validity of the proposed method for the enhancement and identification of weak defect characteristic. In the end, strain test is carried out to further verify the accuracy and reliability of the analysis result obtained by pressure pulsation signal.


Asunto(s)
Algoritmos , Reproducibilidad de los Resultados , Procesamiento de Señales Asistido por Computador , Instrumentos Quirúrgicos , Vibración
11.
J Hum Evol ; 112: 134-147, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28882548

RESUMEN

On the eastern side of Lake Turkana in northern Kenya are extensive Plio-Pleistocene deposits containing a rich diversity of fossil mammals, hominins and flora within the radiometrically dated tuffaceous, lacustrine and fluvial sequence. Reconstruction of this landscape and paleoenvironment are part of an ongoing multinational and multidisciplinary human evolution project in the eastern Turkana Basin. Today there is a huge lake in the Rift Valley but it has fluctuated since the early Pliocene. Silicified wood is fairly common in some areas of the Koobi Fora Formation. One such site is FwJj 14E, alongside one of the tributaries of the Ileret River. Hominin hand and arm bones have been excavated from here in the Okote Member and dated at 1.56-1.36 Ma. The fossils are associated with hominin and bovid footprints. Sixty of the over 100 wood specimens collected have been sectioned and studied. In general the woods have large vessels and an average vulnerability index of 40, which implies a mesic megathermal environment with no water stress. Taxonomically the woods belong to large African families: Caesalpiniaceae (Didelotia idae), Combretaceae (Anogeissus sp.), Putranjivaceae (Euphorbiaceae; Drypetes sp.), Lamiaceae (cf Premna sp.), Malvaceae (Heritiera sp.) and Sapindaceae (Sapindoxylon sp.). Most of these taxa do not occur in the area today because now it is much drier and the local vegetation is predominantly Acacia-Commiphora-Salvadora shrubland. The reconstruction of the paleovegetation supports the interpretation from the fauna, namely, a tall riverine forest with shady refuge trees, possibly some edible fruits, and wooded grassland and more open bushland in the vicinity.


Asunto(s)
Bosques , Fósiles/anatomía & histología , Magnoliopsida/clasificación , Árboles/clasificación , Madera/anatomía & histología , Animales , Ambiente , Hominidae , Kenia , Magnoliopsida/anatomía & histología , Árboles/anatomía & histología , Madera/clasificación
12.
J Eur Acad Dermatol Venereol ; 30(1): 57-9, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25611172

RESUMEN

BACKGROUND: Allergic contact dermatitis caused by wood dust remains uncommon and most cases are occupational. Contact allergy to finished wooden products is even more rare and only few cases of contact dermatitis to wooden furnishings and furniture are described. OBJECTIVE: During 2012-2014 surprisingly many patients with dermatitis associated to sauna baths were referred to our clinic. METHODS: We report three novel cases with allergic contact dermatitis to western red cedar due to exposure during sauna baths. RESULTS: Three cases of non-occupational contact dermatitis to western red cedar were confirmed by patch testing. CONCLUSION: Allergic contact dermatitis to interior decoration or furniture is a rarity, but can be induced by novel exposures, like western red cedar in sauna interior decoration.


Asunto(s)
Dermatitis Alérgica por Contacto/etiología , Diseño Interior y Mobiliario , Baño de Vapor , Thuja , Madera/efectos adversos , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas del Parche
15.
Phytochem Anal ; 25(4): 350-6, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24497327

RESUMEN

INTRODUCTION: Nuclear magnetic resonance (NMR) is one of the most commonly used analytical techniques in plant metabolomics. Although this technique is very reproducible and simple to implement, sample preparation procedures have a great impact on the quality of the metabolomics data. OBJECTIVE: Investigation of different sample preparation methods and establishment of an optimised protocol for untargeted NMR-based metabolomics of Vitis vinifera L. wood samples. METHODS: Wood samples from two different cultivars of V. vinifera with well-defined phenotypes (Gamaret and 2091) were selected as reference materials. Different extraction solvents (successively, dichloromethane, methanol and water, as well as ethyl acetate and 7:3 methanol-water (v/v)) and deuterated solvents (methanol-d4, 7:3 chloroform-d-methanol-d4 (v/v), dimethylsulphoxide-d6 and 9:1 dimethylsulphoxide-d6-water-d2 (v/v)) were evaluated for NMR acquisition, and the spectral quality was compared. The optimal extract concentration, chemical shift stability and peak area repeatability were also investigated. RESULTS: Ethyl acetate was found to be the most satisfactory solvent for the extraction of all representative chemical classes of secondary metabolites in V. vinifera wood. The optimal concentration of dried extract was 10 mg/mL and 7:3 chloroform-d-methanol-d4 (v/v) was the most suitable solvent system for NMR analysis. Multivariate data analysis was used to estimate the biological variation and clustering between different cultivars. CONCLUSION: Close attention should be paid to all required procedures before NMR analysis, especially to the selection of an extraction solvent and a deuterated solvent system to perform an extensive metabolomic survey of the specific matrix.


Asunto(s)
Espectroscopía de Resonancia Magnética/métodos , Metabolómica , Vitis/metabolismo , Madera , Cromatografía Líquida de Alta Presión , Solventes/química
16.
Heliyon ; 10(5): e27228, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38495134

RESUMEN

Leaf litter decomposition is a major component of nutrient cycling which depends on the quality and quantity of the leaf material. Ash trees (Fraxinus excelsior, decay time âˆ¼ 0.4 years) are declining throughout Europe due to a fungal pathogen (Hymenoscyphus fraxineus), which is likely to alter biochemical cycling across the continent. The ecological impact of losing species with fast decomposing leaves is not well quantified. In this study we examine how decomposition of three leaf species with varying decomposition rates including ash, sycamore (Acer pseudoplatanus, decay time âˆ¼ 1.4 years), and beech (Fagus sylvatica, decay time âˆ¼ 6.8 years) differ in habitats with and without ash as the dominant overstorey species. Ten plots (40 m × 40 m) were set up in five locations representing ash dominated and non-ash dominated habitats. In each plot mesh bags (30 cm × 30 cm, 0.5 mm aperture) with a single leaf species (5 g) were used to include (large holes added) and exclude macrofauna invertebrates (with a focus on decomposer organisms such as earthworms, millipedes, and woodlice). The mesh bags were installed in October 2020 and retrieved without replacement at exponential intervals after 6, 12, 24 and 48 weeks. Total leaf mass loss was highest in the ash dominated habitat (ash dominated: 88.5%, non-ash dominated: 66.5%) where macrofauna were the main contributor (macrofauna: 96%, microorganisms/mesofauna: 4%). The difference between macrofauna vs microorganisms and mesofauna was less pronounced in the non-ash dominated habitat (macrofauna: 68%, microorganisms/mesofauna: 31%). Our results suggest that if ash dominated habitats are replaced by species such as sycamore, beech, and oak, the role of macrofauna decomposers will be reduced and leaf litter decomposition rates will decrease by 25%. These results provide important insights for future ash dieback management decisions.

17.
Sci Total Environ ; 949: 175010, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39053534

RESUMEN

To ensure unbiased tree-ring radiocarbon (14C) results, traditional pretreatments carefully isolate wood cellulose from extractives using organic solvents, among other chemicals. The addition of solvents is laborious, time-consuming, and can increase the risk of carbon contamination. Tropical woods show a high diversity in wood-anatomical and extractive composition, but the necessity of organic-solvent extraction for the 14C dating of these diverse woods remains untested. We applied a chemical treatment that excludes the solvent step on the wood of 8 tropical tree species sampled in South-America and Africa, with different wood-anatomical and extractive properties. We analyzed the success of the extractive removal along with several steps of the α-cellulose extraction procedure using Fourier Transform Infrared (FTIR) spectroscopy and further confirmed the quality of 14C measurements after extraction. The α-cellulose extracts obtained here showed FTIR-spectra free of signals from various extractives and the 14C results on these samples showed reliable results. The chemical method evaluated reduces the technical complexity required to prepare α-cellulose samples for 14C dating, and therefore can bolster global atmospheric 14C applications, especially in the tropics.


Asunto(s)
Celulosa , Madera , Madera/química , Celulosa/química , Espectroscopía Infrarroja por Transformada de Fourier , Clima Tropical , Radioisótopos de Carbono/análisis , Árboles , Monitoreo del Ambiente/métodos , Datación Radiométrica/métodos
18.
Sci Rep ; 14(1): 12821, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38834628

RESUMEN

Timber plantations across the world are suffering from the effects of increasingly frequent wildfires, which potentially degrade the wood of affected trees, depending on the exposure temperature and time. However, it is rather complicated to determine the exact temperature of the fire, or the temperature to which the wood was exposed. This study aimed to determine the exposure temperature of wood retrospectively through solid-state NMR analysis. Models were developed from softwood and hardwood samples exposed to defined temperatures, which successfully linked the NMR signal to the exposure temperature. Various fit equations were developed to link the half-width or peak area of the NMR signal to the exposure temperatures. Hard- and softwoods displayed noticeable differences: a linear function best described the half-width in the higher temperature region for Pine and Eucalyptus, whereas a parabolic function for the peak area of Eucalyptus yielded the best correlation to the entire temperature range. This non-destructive and direct method offers a valuable evaluation method to determine, if wood in burnt trees is degraded and can be processed. An informed choice can be made on the decision to use, or discard burnt wood.

19.
Bioresour Technol ; 369: 128315, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36414143

RESUMEN

Lignocellulose represents the most abundant carbon-capturing substance that is convertible for biofuels and bioproduction. Although biomass pretreatments have been broadly applied to reduce lignocellulose recalcitrance for enhanced enzymatic saccharification, they mostly require strong conditions with potential secondary waste release. By classifying all major types of pretreatments that have been recently conducted with different sources of lignocellulose substrates, this study sorted out their distinct roles for wall polymer extraction and destruction, leading to the optimal pretreatments evaluated for cost-effective biomass enzymatic saccharification to maximize biofuel production. Notably, all undigestible lignocellulose residues are also aimed for effective conversion into value-added bioproduction. Meanwhile, desired pretreatments were proposed for the generation of highly-valuable nanomaterials such as cellulose nanocrystals, lignin nanoparticles, functional wood, carbon dots, porous and graphitic nanocarbons. Therefore, this article has proposed a novel strategy that integrates cost-effective and green-like pretreatments with desirable lignocellulose substrates for a full lignocellulose utilization with zero-biomass-waste liberation.


Asunto(s)
Biocombustibles , Lignina , Lignina/química , Biocombustibles/análisis , Celulosa/química , Pared Celular , Biomasa
20.
Asian Pac J Cancer Prev ; 24(10): 3555-3561, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37898863

RESUMEN

BACKGROUND: Shielding from radiation and plan dose verification is vital during the potential applications in industrial and medical applications. A number of natural composites have been investigated for protecting against high-energy X-ray shielding. OBJECTIVE: The aim is to learn about how natural composites behave under various X-ray energies at STP. MATERIAL AND METHODS: The radiological parameters of wood samples were determined using computed tomography imaging, specifically relative electron density (RED), Hounsfield units (HUs), and mass density (MD). Percentage attenuation was measured using a semiflux ionization chamber incorporated with a brass build-up cap and an ionization chamber placed at the beam Isocenter for a different type of natural composite. Measurements are being carried out on a Linear accelerator at an SSD of 110 cm with different collimator sizes. RESULTS: Measured values of  HUs, RED, and MD were -232 ± 40, 0.738 ± 0.039, 0.768 ± 0.024 g/cc,-368 ± 41, 0.662 ± 0.047, 0.632 ± 0.024 g/cc, -334 ± 44, 0.639 ± 0.042, 0.666 ± 0.026 g/cc, -370±61, 0.604±0.059, 0.63± 0.036 g/cc, -433±39, 0.543±0.038, 0.608 ± 0.035 g/cc, -382±54, 0.5±0.052, 0.618 ± 0.0316 g/cc, -292±68, 0.680±0.066, 0.708 ± 0.039 g/cc, -298±27, 0.680±0.0229, 0.702± 0.131 g/cc, for Acacia Nilotica, Mangifera Indica, Azadirachta Indica, Tectona Grandis L, Ficus Religiosa, Tecomella Undulata, Sesamum Indicum, Pinus respectively. CONCLUSION: Measurements show that attenuation is affected by the energy of incident photons, collimator opening, and the type of density of the wood. Various radiological parameters were determined for wood samples that can be utilized to create inhomogeneous phantoms in dosimetry. The largest attenuation is found in Acacia Nilotica and Sesamum Indicum, while the lowest attenuation is found in Ficus religiosa.


Asunto(s)
Radiología , Radiometría , Humanos , Rayos X , Radiometría/métodos , Fotones , Tomografía Computarizada por Rayos X/métodos , Fantasmas de Imagen
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