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The particle size distribution (PSD) in emulsion polymerization (EP) has been modeled in the past using either the pseudo bulk (PB) or the 0-1/0-1-2 approaches. There is some controversy on the proper type of model to be used to simulate the experimental PSDs, which are apparently broader than the theoretical ones. Additionally, the numerical technique employed to solve the model equations, involving hyperbolic partial differential equations (PDEs) with moving and possibly steep fronts, has to be precise and robust, which is not a trivial matter. A deterministic kinetic model for the PSD evolution of ab initio EP of vinyl monomers was developed to investigate these issues. The model considers three phases, micellar nucleation, and particles that can contain n≥0 radicals. Finite volume (FV) and weighted-residual methods are used to solve the system of PDEs and compared; their limitations are also identified. The model was validated by comparing predictions with data of monomer conversion and PSD for the batch emulsion homopolymerization of styrene (Sty) and methyl methacrylate (MMA) using sodium dodecyl sulfate (SDS)/potassium persulfate (KPS) at 60 °C, as well as the copolymerization of Sty-MMA (50/50; mol/mol) at 50 and 60 °C. It is concluded that the PB model has a structural problem when attempting to adequately represent PSDs with steep fronts, so its use is discouraged. On the other hand, there is no generalized evidence of the need to add a stochastic term to enhance the PSD prediction of EP deterministic models.

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Nanoscale particles described by Mie resonance in the UV-vis-NIR region are in high demand for optical applications. Controlling the shape and size of these particles is essential, as it results in the ability to control the wavelength of the Mie resonance peak. In this work, we study the extensive scattering properties of gadolinium niobate particles with complex bar- and cube-like shapes in the UV-vis-NIR region. We perform our experimental analysis by characterizing the morphology and extinction spectra, and our theoretical study by implementing a Mie scattering model for a distribution of spherical particles. We can accurately model the size distribution and extinction spectra of complex shaped particles and isolate the contribution of aggregates to the extinction spectra. We can separate the contributions of dipoles, quadrupoles, and octupoles to the Mie resonances for their respective electric and magnetic parts. Our results show that we can tune the broad Mie resonance peak in the extinction spectra by the nanoscale properties of our system. This behavior can aid in the design of lasing and luminescence-enhanced systems. These dielectric gadolinium niobate submicron particles are excellent candidates for light manipulation on the nanoscale.

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The automated search software integrated with a scanning electron microscope (SEM/EDS) has been the standard tool for detecting inorganic gunshot residues (iGSR) for several decades. The detection of these particles depends on various factors such as collection, preservation, contamination with organic matter, and the method for sample analysis. This article focuses on the influence of equipment resolution setup on the backscattered electron images of the sample. The pixel size of these images plays a crucial role in determining the detectability of iGSR particles, especially those with sizes close to the pixel size. In this study, we calculated the probability of missing all characteristic iGSR particles in a sample using an SEM/EDS automated search and how it depends on the image pixel resolution setup. We developed and validated an iGSR particle detection model that links particle size with equipment registers and applied it to 320 samples analyzed by a forensic science laboratory. Our results show that the probability of missing all characteristic iGSR particles due to their size is below 5% for pixel sizes below 0.32 µm2 . These findings indicate that pixel sizes as large as twice the one commonly used in laboratory casework, that is, 0.16 µm2 , are effective for initial sample scanning, yielding good detection rates of characteristic particles that could exponentially reduce laboratory workload.

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We investigated whether excessive retroperitoneal adipose tissue (AT) expansion programmed by maternal obesity (MO) affects adipocyte size distribution and gene expression in relation to adipocyte proliferation and differentiation in male and female offspring (F1) from control (F1C) and obese (F1MO) mothers. Female Wistar rats (F0) ate a control or high-fat diet from weaning through pregnancy and lactation. F1 were weaned onto a control diet and euthanized at 110 postnatal days. Fat depots were weighed to estimate the total AT. Serum glucose, triglyceride, leptin, insulin, and the insulin resistance index (HOMA-IR) were determined. Adipocyte size and adipogenic gene expression were examined in retroperitoneal fat. Body weight, retroperitoneal AT and adipogenesis differed between male and female F1Cs. Retroperitoneal AT, glucose, triglyceride, insulin, HOMA-IR and leptin were higher in male and female F1MO vs. F1C. Small adipocytes were reduced in F1MO females and absent in F1MO males; large adipocytes were increased in F1MO males and females vs. F1C. Wnt, PI3K-Akt, and insulin signaling pathways in F1MO males and Egr2 in F1MO females were downregulated vs. F1C. MO induced metabolic dysfunction in F1 through different sex dimorphism mechanisms, including the decreased expression of pro-adipogenic genes and reduced insulin signaling in males and lipid mobilization-related genes in females.

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Effect sizes of school-based intervention are commonly described as small to moderate when using Cohen's conventional effect size cutoffs (small [0.2], medium [0.5], and large [0.8]). However, Jacob Cohen's rule of thumb might vary across different areas of research, nature of the intervention, and population, because effect sizes are context-dependent. Moreover, when planning research studies, minimum detectable effect sizes are used to calculate the sample size. In the present study, we investigate whether conventional effect size cutoffs (small [0.2], medium [0.5], and large [0.8]) represent the reported distribution of effect sizes in school-based anti-bullying intervention. To determine small, medium, and large effect sizes, we calculated the effect size distribution (ESD) using 50th percentile effect size (medium effect) of the distributions of effect sizes provided by a recent meta-analysis on school-based anti-bullying intervention. Also, the 25th and 75th percentile effects, as they are equidistant from the average effect size, were used redefining small and large effects, respectively. Results showed that 0.07, 0.123, and 0.227 represent small, medium, and large effect sizes in anti-bullying interventions. Our results indicate that Cohen's suggested effect size thresholds (0.2, 0.5, and 0.8) overestimate effect sizes when compared to the real-world context of school based anti-bullying interventions. We also propose sample sizes required to reliably detect small, medium, and large percentile effect sizes in anti-bullying interventions.

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Abstract Solubility of pharmaceutical drugs in organic solvents is one of the important parameters to understand the equilibrium concentration of solute-solvent, which helps optimize and design crystallization conditions to obtain the desired product crystals. In the present study, Chlorzoxazone (CHZ) is used as a model pharmaceutical compound to investigate the equilibrium solubility, the influence of solvent and the operating conditions on the shape, and the size distribution. The solubility of CHZ is determined in organic solvents like Isopropanol, Ethanol, and 2-Ethoxyethylacetate, Ethylacetate and Ethyllactate using shake flask method from -5ºC to 60ºC. The solubility of CHZ in these solvents shows an increasing trend as the temperature increases in the following order: ethyllactate + water (0.5+0.5) < ethylacetate < isopropanol < ethanol < 2-ethoxyethylacetate < ethyllactate + water (0.75+0.25). The solvents, isopropanol, ethanol, and ethyl lactate, produce needle-shaped crystals, while 2-ethoxyethylacetate and ethyl acetate tend to produce plate shaped crystals. CHZ crystals obtained from 2-ethoxyethylacetate tend to have plate shaped crystals with a lower aspect ratio and are selected for batch cooling crystallization experiments performed at different cooling rates, and agitation. It is found that the agitation at 300 rpm and the cooling rate 0.2ºC/min produce more uniform crystal size distribution

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The control of inclusions in steel components is essential to guarantee strong performance. The reliable characterization of inclusion populations is essential not only to evaluate the quality of the components but also to allow the use of analytical procedures for the comparison and discrimination of inclusion populations. In this work, inclusion size distributions in wire rod specimens from six plant-scale heats were measured and analyzed. For the measurements, the metallographic procedure specified in the ASTM E2283 standard was used. The population density function (PDF) approach and the extreme value statistical procedure specified in the ASTM E2283 standard were used to analyze the whole size distribution and the upper tail of the size distribution, respectively. The PDF approach allowed us to identify differences among inclusion size distributions and showed that new inclusions were not formed after the liquid steel treatment process. The extreme value statistical procedure led to the prediction of the maximum inclusion length for each heat, which was used for the statistical discrimination of heats. Furthermore, the estimation of the probability of finding an inclusion larger than a given inclusion size using the extreme value theory allowed us to order the heats for different critical inclusion sizes.

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X-ray scattering and diffraction phenomena are widely used as analytical tools in nanoscience. Size discrepancies between the two phenomena are commonly observed in crystalline nanoparticle systems. The root of the problem is that each phenomenon is affected by size distribution differently, causing contrasting shifts between the two methods. Once understood, the previously discrepant results lead to a simple formula for obtaining the nanoparticle size distribution.

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Sandy soils (containing > 50% sand) are widely distributed worldwide and are characterized by their poor structure, low organic matter, weak hydraulic and nutritional properties, and low crop productivity. Using a 2-year pot experiment, in this study, we investigated the effects of humic acid (HA) as a soil amendment and study two plant growth stimulants (PGSs), zinc oxide nanoparticles (ZnONPs), and L-tryptophan (L-TRP), as a foliar application on wheat grown in nutrient-poor sandy soil. Three HA rates (0 (HA0), 0.2 (HA0.2), and 0.4 (HA0.4) g kg-1 soil) and five PGS levels [control, 50 mg l-1 (ZnONPs50), 100 mg l-1 (ZnONPs100), 0.25 mmol l-1 (L-TRP0.25), and 0.5 mmol l-1 (L-TRP0.5)] were used. The soil hydro-physico-chemical properties, morpho-physiological responses, yield, and quality were measured. HA addition amended the soil structure by allowing rapid macroaggregate formation, decreasing bulk density and pH, and increasing porosity and electrical conductivity, thereby improving soil hydraulic properties. HA0.2 and HA0.4 additions improved growth, yield components, and grain minerals, resulting in higher grain yield by 28.3-54.4%, grain protein by 10.2-13.4%, wet gluten by 18.2-23.3%, and dry gluten by 23.5-29.5%, respectively, than HA0. Foliar application of ZnONPs or L-TRP, especially at higher concentrations compared to the control, noticeably recorded the same positive results as HA treatments. The best results were achieved through the integration of HA0.4 + ZnONPs100 or L-TRP0.5 to the tested nutrient-poor sandy soil. The interactive application of HA0.4 + ZnONPs100 or L-TRP0.5 and the use of mineral fertilizer, which is considered a surplus point in permaculture, can be recommended for sustainable wheat production in nutrient-poor sandy soil.

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The research presents the inter-comparison of atmospheric variables measured by 9 automatic weather stations. This set of data was compared with the measurements of other weather stations in order to standardize the values that must be adjusted when taken to different areas. The data of a set of a total of 9 GMX500, which measures conventional meteorological variables, and 10 WS100 sensors, which measures precipitation parameters. The automatic stations were set up at the Huancayo Observatory (Geophysical Institute of Peru) for a period of 5 months. The data set of GMX500 were evaluated comparing with the average of the 9 sensors and the WS100 was compared with an optical disdrometer Parsivel2. The temperature, pressure, relative humidity, wind speed, rainfall rate, and drop size distribution were evaluated. A pair of GMX500 sensors presented high data dispersion; it was found found that the errors came from a bad configuration; once this problem was solved, good agreement was archived, with low RMSE and high correlation. It was found that the WS100 sensors overestimate the precipitation with a percentage bias close to 100% and the differences increase with the greater intensity of rain. The drop size distribution retrieved by WS100 have unrealistic behavior with higher concentrations in diameters of 1 mm and 5 mm, in addition to a flattened curve.

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Tree size shapes forest carbon dynamics and determines how trees interact with their environment, including a changing climate. Here, we conduct the first global analysis of among-site differences in how aboveground biomass stocks and fluxes are distributed with tree size. We analyzed repeat tree censuses from 25 large-scale (4-52 ha) forest plots spanning a broad climatic range over five continents to characterize how aboveground biomass, woody productivity, and woody mortality vary with tree diameter. We examined how the median, dispersion, and skewness of these size-related distributions vary with mean annual temperature and precipitation. In warmer forests, aboveground biomass, woody productivity, and woody mortality were more broadly distributed with respect to tree size. In warmer and wetter forests, aboveground biomass and woody productivity were more right skewed, with a long tail towards large trees. Small trees (1-10 cm diameter) contributed more to productivity and mortality than to biomass, highlighting the importance of including these trees in analyses of forest dynamics. Our findings provide an improved characterization of climate-driven forest differences in the size structure of aboveground biomass and dynamics of that biomass, as well as refined benchmarks for capturing climate influences in vegetation demographic models.

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Microplastics have been studied in sediments from coastal and aquatic environments, but contamination of mangrove soils is still relatively unknown in most mangroves around the world. In this study, the presence of microplastics was investigated in six mangrove soils around the Todos Santos Bay (TSB), the largest and most important navigable bay on the Brazilian coast. Samples were collected at three depths (surface, 10 cm, and 30 cm) at three different distances from the lower tidal area. Ten grams of soil were sieved in a 150 µm mesh and centrifuged with ZnCl2 solution (density of 1.5 kg dm-3) for the extraction of microplastics. The microplastics were quantified, measured, and described using a systematic photographic method and the ImageJ program. Microplastics were abundant in all samples, with a mean of 10,782 ± 7,671 items kg-1 (max.: 31,087 items kg-1, only one sample <2,000 items kg-1), higher than any other value reported worldwide. The abundances varied among the six mangroves studied, with a predominance of fibers and mean size of 196 µm. Even remote mangroves were highly polluted, reflecting a large dispersion of the pollutants. The abundance did not differ significantly between soil depths, evidencing a continuous input and burial of microplastics in the soil up to 30 cm. The investigation of the source of microplastics and their presence in water and biota is urgent in this Brazilian region, and these results emphasize the need for global actions to protect coastal ecosystems.

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One of the main factors limiting the productivity of potatoes (Solanum tuberosum L.) is water stress. Two irrigation systems: full irrigation (I) and rainfed conditions (R), were compared over the growing seasons from 2012-13 to 2019-20. The evaluated varieties were Desiree, Karú-INIA, Patagonia-INIA, Puyehue-INIA, Yagana-INIA, Yaike, and Porvenir. This study determined (i) the yield and tuber size distribution, (ii) their relationship between productivity and environmental conditions, and (iii) the most drought-tolerant varieties based on drought tolerance indices. Nine indices including yield index (YI), tolerance index (TOL), mean productivity (MP), geometric mean productivity (GMP), harmonic mean (Harm), stress tolerance index (STI), harmonic mean productivity (HMP), yield reduction (Yr), and stress susceptible index (SSI) were calculated by using tuber yield under I and R conditions. Tuber yield under R conditions decreased by 27 and 34%. However, the highest yield under R conditions occurred in years with more precipitation between 60 and 120 days after planting (DAP; ±60 mm). Under R conditions, the varieties Porvenir, Patagonia-INIA, Yaike, and Puyehue-INIA showed more tolerance to water stress. Water stress negatively affected tuber size distribution, reducing the production of tubers with size >65 mm by 50-60%. The best indices to study drought tolerance were TOL, MP, GMP, Harm, STI, and HMP. This study suggests that in southern Chile, an area with big yield potential, typically cultivated as rainfed, with cool temperate climate conditions and favorable soil properties for potatoes, as Andisols, available rainfall is still a constraint for yield. Therefore, using more water stress-tolerant varieties and providing supplementary irrigation between 60 and 120 DAP are critical to optimize yield and avoid the failure of the crop in years with remarkably low precipitations, which will be more pronounced in the future according to weather trends. These results exemplify how much we can lose in productivity in rainfed conditions even in one of the most favorable areas for growing potatoes in the world and how risky this situation can be for the performance of the potato farms in the future.

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The development of greener nano-constructs with noteworthy biological activity is of supreme interest, as a robust choice to minimize the extensive use of synthetic drugs. Essential oils (EOs) and their constituents offer medicinal potentialities because of their extensive biological activity, including the inhibition of fungi species. However, their application as natural antifungal agents are limited due to their volatility, low stability, and restricted administration routes. Nanotechnology is receiving particular attention to overcome the drawbacks of EOs such as volatility, degradation, and high sensitivity to environmental/external factors. For the aforementioned reasons, nanoencapsulation of bioactive compounds, for instance, EOs, facilitates protection and controlled-release attributes. Nanoliposomes are bilayer vesicles, at nanoscale, composed of phospholipids, and can encapsulate hydrophilic and hydrophobic compounds. Considering the above critiques, herein, we report the in-house fabrication and nano-size characterization of bioactive oregano essential oil (Origanum vulgare L.) (OEO) molecules loaded with small unilamellar vesicles (SUV) nanoliposomes. The study was focused on three main points: (1) multi-compositional fabrication nanoliposomes using a thin film hydration-sonication method; (2) nano-size characterization using various analytical and imaging techniques; and (3) antifungal efficacy of as-developed OEO nanoliposomes against Trichophyton rubrum (T. rubrum) by performing the mycelial growth inhibition test (MGI). The mean size of the nanoliposomes was around 77.46 ± 0.66 nm and 110.4 ± 0.98 nm, polydispersity index (PdI) of 0.413 ± 0.015, zeta potential values up to -36.94 ± 0.36 mV were obtained by dynamic light scattering (DLS). and spherical morphology was confirmed by scanning electron microscopy (SEM). The presence of OEO into nanoliposomes was displayed by attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy. Entrapment efficiency values of 79.55 ± 6.9% were achieved for OEO nanoliposomes. In vitro antifungal activity of nanoliposomes tested against T. rubrum strains revealed that OEO nanoliposomes exhibited the highest MGI, 81.66 ± 0.86%, at a concentration of 1.5 µL/mL compared to the rest of the formulations. In summary, this work showed that bioactive OEO molecules with loaded nanoliposomes could be used as natural antifungal agents for therapeutical purposes against T. rubrum.

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Exposure to high concentrations of particulate matter (PM) is associated with a number of adverse health effects. However, it is unclear which aspects of PM are most hazardous, and a better understanding of particle sizes and personal exposure is needed. We characterized particle size distribution (PSD) from biomass-related pollution and assessed total and regional lung-deposited doses using multiple-path deposition modeling. Gravimetric measurements of kitchen and personal PM2.5 (<2.5 µm in size) exposures were collected in 180 households in rural Puno, Peru. Direct-reading measurements of number concentrations were collected in a subset of 20 kitchens for particles 0.3-25 µm, and the continuous PSD was derived using a nonlinear least-squares method. Mean daily PM2.5 kitchen concentration and personal exposure was 1205 ± 942 µg/m3 and 115 ± 167 µg/m3 , respectively, and the mean mass concentration consisted of a primary accumulation mode at 0.21 µm and a secondary coarse mode at 3.17 µm. Mean daily lung-deposited surface area (LDSA) and LDSA during cooking were 1009.6 ± 1469.8 µm2 /cm3 and 10,552.5 ± 8261.6 µm2 /cm3 , respectively. This study presents unique data regarding lung deposition of biomass smoke that could serve as a reference for future studies and provides a novel, more biologically relevant metric for exposure-response analysis compared to traditional size-based metrics.

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ABSTRACT: This study evaluated the effects of the physically effective fiber (peNDF) content on nutrient composition of the total mixed ration (TMR), orts and fecal parameters in 15 commercial beef feedlots. The particle size distribution of TMR was measured adopting Penn State Particle Size Separator (PSPS). Samples were evaluated for dry matter (DM), ash, ether extract (EE), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and starch content. Fecal samples were also evaluated for pH and score. The feedlots were categorized into peNDF<20% and peNDF ≥ 20%. Data were analyzed by a model that included fixed effects of treatment and covariates (sex and genetic groups). Levels of DM, CP, EE and starch were lower in TMR with peNDF ≥ 20% (P<0.05). Fecal dry matter was higher and morning fecal pH was lower for TMR with peNDF<20% (P<0.05). Physically effective fiber changed nutrient levels in TMR, orts, fecal pH and DM. So, using PSPS and fecal parameters are practical and indirect tools for measuring fecal starch and assessing the effectiveness of the diet supplied to ruminants.

RESUMO: O objetivo desse estudo foi avaliar o teor de fibra fisicamente efetiva (FDNfe) de dietas totais e seus efeitos nos nutrientes da dieta, das sobras e nos parâmetros fecais de bovinos de corte em 15 confinamentos comerciais. As amostras da dieta foram separadas utilizando a peneira Penn State Particle Size Separator (PSPS). As amostras foram analisadas quanto aos teores de matéria seca (MS), matéria mineral (MM), extrato etéreo (EE), proteína bruta (PB), fibra em detergente neutro (FDN), fibra em detergente ácido (FDA) e amido. Nas amostras de fezes também foram avaliadas o escore e pH fecal. Os confinamentos foram categorizados em dois tratamentos: FDNfe<20% e FDNfe≥20%. Os dados foram analisados ​​ por um modelo que incluiu os efeitos de grupo e covariável (sexo e grupo genético). Os teores de MS, PB, EE e amido foram menores nas dietas com FDNfe≥20%(P<0,05). A MS fecal foi maior e pH fecal matinal foi menor nas dietas com FDNfe<20% (P<0,05). Sendo assim a efetividade da fibra alterou os nutrientes da dieta total e sobras, bem como as variáveis pH e MS fecal. Com isso, o uso de PSPS e parâmetros fecais são ferramentas práticas e indiretas para medir o amido fecal e a efetividade da dieta em confinamentos de bovinos comerciais.

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This study evaluated the effects of the physically effective fiber (peNDF) content on nutrient composition of the total mixed ration (TMR), orts and fecal parameters in 15 commercial beef feedlots. The particle size distribution of TMR was measured adopting Penn State Particle Size Separator (PSPS). Samples were evaluated for dry matter (DM), ash, ether extract (EE), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and starch content. Fecal samples were also evaluated for pH and score. The feedlots were categorized into peNDF 20% and peNDF 20%. Data were analyzed by a model that included fixed effects of treatment and covariates (sex and genetic groups). Levels of DM, CP, EE and starch were lower in TMR with peNDF 20% (P 0.05). Fecal dry matter was higher and morning fecal pH was lower for TMR with peNDF 20% (P 0.05). Physically effective fiber changed nutrient levels in TMR, orts, fecal pH and DM. So, using PSPS and fecal parameters are practical and indirect tools for measuring fecal starch and assessing the effectiveness of the diet supplied to ruminants.(AU)

O objetivo desse estudo foi avaliar o teor de fibra fisicamente efetiva (FDNfe) de dietas totais e seus efeitos nos nutrientes da dieta, das sobras e nos parâmetros fecais de bovinos de corte em 15 confinamentos comerciais. As amostras da dieta foram separadas utilizando a peneira Penn State Particle Size Separator (PSPS). As amostras foram analisadas quanto aos teores de matéria seca (MS), matéria mineral (MM), extrato etéreo (EE), proteína bruta (PB), fibra em detergente neutro (FDN), fibra em detergente ácido (FDA) e amido. Nas amostras de fezes também foram avaliadas o escore e pH fecal. Os confinamentos foram categorizados em dois tratamentos: FDNfe 20% e FDNfe20%. Os dados foram analisados por um modelo que incluiu os efeitos de grupo e covariável (sexo e grupo genético). Os teores de MS, PB, EE e amido foram menores nas dietas com FDNfe20%(P 0,05). A MS fecal foi maior e pH fecal matinal foi menor nas dietas com FDNfe 20% (P 0,05). Sendo assim a efetividade da fibra alterou os nutrientes da dieta total e sobras, bem como as variáveis pH e MS fecal. Com isso, o uso de PSPS e parâmetros fecais são ferramentas práticas e indiretas para medir o amido fecal e a efetividade da dieta em confinamentos de bovinos comerciais.(AU)

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Cassiopea jellyfish have successfully invaded several marine ecosystems worldwide. We investigated if Cassiopea andromeda grows larger (umbrella size) and if their populations are more stable in shrimp farms than in mangroves in the Brazilian coast. Our results show that jellyfish abundance is higher in the shrimp farm during the rainy season and in the mangrove during dry season. The population is stable during both seasons in the shrimp farm, but unstable in the mangroves, as jellyfish are absent during rainy season. Shrimp farm-associated jellyfish are three times larger than those in the mangroves, regardless of season. We recorded the largest (49.2 cm of umbrella diameter) ever C. andromeda individual in the shrimp farm. Unlike the mangroves, the shrimp farm provides environmental intra-annual stability that promotes jellyfish growth and population persistence. Therefore, C. andromeda populations can be seasonally dynamic and artificial environments such as aquaculture facilities may facilitate the invasion process.

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The soil water retention curve is one of the most important properties used to predict the amount of water available to plants, pore size distribution and hydraulic conductivity, as well as knowledge for drainage and irrigation modeling. Depending on the method of measurement adopted, the water retention curve can involve the application of several wetting and drying (W-D) cycles to a soil sample. The method assumes soil pore structure is constant throughout however most of the time soil structure is dynamic and subjected to change when submitted to continuous W-D. Consequently, the pore size distribution, as well as other soil morphological properties can be affected. With this in mind, high resolution X-ray Computed micro-Tomography was utilized to evaluate changes in the soil pore architecture following W-D cycles during the procedure of the water retention curve evaluation. Two different soil sample volumes were analyzed: ROIW (whole sample) and ROIHC (the region close to the bottom of the sample). The second region was selected due to its proximity to the hydraulic contact of the soil with the water retention curve measurement apparatus. Samples were submitted to the following W-D treatments: 0, 6 and 12 W-D. Results indicated the soil changed its porous architecture after W-D cycles. The image-derived porosity did not show differences after W-D cycles for ROIW; while for ROIHC it increased porosity. The porosity was also lower in ROIHC in comparison to ROIW. Pore connectivity improved after W-D cycles for ROIHC, but not for ROIW. W-D cycles induced more aligned pores for both ROIs as observed by the tortuosity results. Pore shape showed changes mainly for ROIW for the equant and triaxial shaped pores; while pore size was significantly influenced by the W-D cycles. Soil water retention curve measurements showed that W-D cycles can affect water retention evaluation and that the changes in the soil morphological properties can play an important role in it.

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The maximum entropy theory of ecology (METE) applies the concept of "entropy" from information theory to predict macroecological patterns. The energetic predictions of the METE rely on predetermined metabolic scaling from external theories, and this reliance diminishes the testability of the theory. In this work, I build parameterized METE models by treating the metabolic scaling exponent as a free parameter, and I use the maximum-likelihood method to obtain empirically plausible estimates of the exponent. I test the models using the individual tree data from an oak-dominated deciduous forest in the northeastern United States and from a tropical forest in central Panama. My analysis shows that the metabolic scaling exponents predicted from the parameterized METE models deviate from that of the metabolic theory of ecology and exhibit large variation, at both community and population levels. Assemblage and population abundance may act as ecological constraints that regulate the individual-level metabolic scaling behavior. This study provides a novel example of the use of the parameterized METE models to reveal the biological processes of individual organisms. The implication and possible extensions of the parameterized METE models are discussed.

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