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Introduction: This study aimed to develop, implement, and test a visuo-haptic simulator designed to explore the buoyancy phenomenon for freshman engineering students enrolled in physics courses. The primary goal was to enhance students' understanding of physical concepts through an immersive learning tool. Methods: The visuo-haptic simulator was created using the VIS-HAPT methodology, which provides high-quality visualization and reduces development time. A total of 182 undergraduate students were randomly assigned to either an experimental group that used the simulator or a control group that received an equivalent learning experience in terms of duration and content. Data were collected through pre- and post-tests and an exit-perception questionnaire. Results: Data analysis revealed that the experimental group achieved higher learning gains than the control group ( p = 0.079). Additionally, students in the experimental group expressed strong enthusiasm for the simulator, noting its positive impact on their understanding of physical concepts. The VIS-HAPT methodology also reduced the average development time compared to similar visuo-haptic simulators. Discussion: The results demonstrate the efficacy of the buoyancy visuo-haptic simulator in improving students' learning experiences and validate the utility of the VIS-HAPT method for creating immersive educational tools in physics., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Neri, Noguez, Escobar-Castillejos, Robledo-Rella, García-Castelán, Gonzalez-Nucamendi, Magana and Benes.)

Selection for yield at high planting density has reshaped the leaf canopy of maize, improving photosynthetic productivity in high density settings. Further optimization of canopy architecture may be possible. However, measuring leaf angles, the widely studied component trait of leaf canopy architecture, by hand is a labor and time intensive process. Here, we use multiple, calibrated, 2D images to reconstruct the 3D geometry of individual sorghum plants using a voxel carving based algorithm. Automatic skeletonization and segmentation of these 3D geometries enable quantification of the angle of each leaf for each plant. The resulting measurements are both heritable and correlated with manually collected leaf angles. This automated and scaleable reconstruction approach was employed to measure leaf-by-leaf angles for a population of 366 sorghum plants at multiple time points, resulting in 971 successful reconstructions and 3,376 leaf angle measurements from individual leaves. A genome wide association study conducted using aggregated leaf angle data identified a known large effect leaf angle gene, several previously identified leaf angle QTL from a sorghum NAM population, and novel signals. Genome wide association studies conducted separately for three individual sorghum leaves identified a number of the same signals, a previously unreported signal shared across multiple leaves, and signals near the sorghum orthologs of two maize genes known to influence leaf angle. Automated measurement of individual leaves and mapping variants associated with leaf angle reduce the barriers to engineering ideal canopy architectures in sorghum and other grain crops., Competing Interests: James C. Schnable has an equity interests in Data2Bio, a company that provides genotyping services using the same protocol employed for genotyping in this study., (©2021 Tross et al.)

Changes in canopy architecture traits have been shown to contribute to yield increases. Optimizing both light interception and light interception efficiency of agricultural crop canopies will be essential to meeting the growing food needs. Canopy architecture is inherently three-dimensional (3D), but many approaches to measuring canopy architecture component traits treat the canopy as a two-dimensional (2D) structure to make large scale measurement, selective breeding, and gene identification logistically feasible. We develop a high throughput voxel carving strategy to reconstruct 3D representations of sorghum from a small number of RGB photos. Our approach builds on the voxel carving algorithm to allow for fully automatic reconstruction of hundreds of plants. It was employed to generate 3D reconstructions of individual plants within a sorghum association population at the late vegetative stage of development. Light interception parameters estimated from these reconstructions enabled the identification of known and previously unreported loci controlling light interception efficiency in sorghum. The approach is generalizable and scalable, and it enables 3D reconstructions from existing plant high throughput phenotyping datasets. We also propose a set of best practices to increase 3D reconstructions' accuracy., Competing Interests: The authors are not aware of any conflict of interest arising from drafting this manuscript., (© 2020 The Authors. Plant Direct published by American Society of Plant Biologists and the Society for Experimental Biology and John Wiley & Sons Ltd.)

Computational models of plants have identified gaps in our understanding of biological systems, and have revealed ways to optimize cellular processes or organ-level architecture to increase productivity. Thus, computational models are learning tools that help direct experimentation and measurements. Models are simplifications of complex systems, and often simulate specific processes at single scales (e.g. temporal, spatial, organizational, etc.). Consequently, single-scale models are unable to capture the critical cross-scale interactions that result in emergent properties of the system. In this perspective article, we contend that to accurately predict how a plant will respond in an untested environment, it is necessary to integrate mathematical models across biological scales. Computationally mimicking the flow of biological information from the genome to the phenome is an important step in discovering new experimental strategies to improve crops. A key challenge is to connect models across biological, temporal and computational (e.g. CPU versus GPU) scales, and then to visualize and interpret integrated model outputs. We address this challenge by describing the efforts of the international Crops in silico consortium., (© 2020 Society for Experimental Biology and John Wiley & Sons Ltd.)

Multi-scale models can facilitate whole plant simulations by linking gene networks, protein synthesis, metabolic pathways, physiology, and growth. Whole plant models can be further integrated with ecosystem, weather, and climate models to predict how various interactions respond to environmental perturbations. These models have the potential to fill in missing mechanistic details and generate new hypotheses to prioritize directed engineering efforts. Outcomes will potentially accelerate improvement of crop yield, sustainability, and increase future food security. It is time for a paradigm shift in plant modeling, from largely isolated efforts to a connected community that takes advantage of advances in high performance computing and mechanistic understanding of plant processes. Tools for guiding future crop breeding and engineering, understanding the implications of discoveries at the molecular level for whole plant behavior, and improved prediction of plant and ecosystem responses to the environment are urgently needed. The purpose of this perspective is to introduce Crops in silico (cropsinsilico.org), an integrative and multi-scale modeling platform, as one solution that combines isolated modeling efforts toward the generation of virtual crops, which is open and accessible to the entire plant biology community. The major challenges involved both in the development and deployment of a shared, multi-scale modeling platform, which are summarized in this prospectus, were recently identified during the first Crops in silico Symposium and Workshop.

The fovea is one of the most studied retinal specializations in vertebrates, which consists of an invagination of the retinal tissue with high packing of cone photoreceptors, leading to high visual resolution. Between species, foveae differ morphologically in the depth and width of the foveal pit and the steepness of the foveal walls, which could influence visual perception. However, there is no standardized methodology to measure the contour of the foveal pit across species. We present here FOVEA, a program for the quantification of foveal parameters (width, depth, slope of foveal pit) using images from histological cross-sections or optical coherence tomography (OCT). FOVEA is based on a new algorithm to detect the inner retina contour based on the color variation of the image. We evaluated FOVEA by comparing the fovea morphology of two Passerine birds based on histological cross-sections and its performance with data from previously published OCT images. FOVEA detected differences between species and its output was not significantly different from previous estimates using OCT software. FOVEA can be used for comparative studies to better understand the evolution of the fovea morphology in vertebrates as well as for diagnostic purposes in veterinary pathology. FOVEA is freely available for academic use and can be downloaded at: http://estebanfj.bio.purdue.edu/fovea.

In 2006, levels of seven indicator polychlorinated biphenyl congeners (PCB28, 52, 101, 118, 138, 153, and 180) in blood serum of 202 blood donors residing for more than 2 years in five urban areas included in the Czech Human Biomonitoring project were measured by GC/MS/MS method. PCB congeners 138, 153 and 180 accounted for about 97% of the sum of the indicator congeners analyzed. Overall, the median and 95th percentile of the most abundant congener PCB 153 were 438 ng/g lipid and 1079 ng/g lipid, respectively. The highest median levels were found in Uherské Hradiste (669 ng/g lipid) and Ostrava (672 ng/g lipid in males compared to 341 ng/g lipid in females). Serum PCB concentrations were significantly associated with age, gender, place of residence and smoking habit, but not with body mass index and education. The results suggest the importance of PCB body burden in the Czech general population and the existence of hot spots.

Variations in the levels of Cu, Se and Zn in blood were analyzed in relation to gender, age, BMI, smoking and hormonal contraception. The blood samples were collected from 3,207 blood donors (2,362 men, 845 women) during years 1996-2003. Blood concentrations of these elements were in the same range as those found for populations of other European countries. Significant differences exist between men and women, in blood concentration, for Cu (840 microg Cu.l(-1) vs. 970 microg Cu.l(-1), p<0.01) and Zn (6,780 microg Zn.l(-1) vs. 6,235 microg Zn.l(-1), p<0.01) only. The level of Cu in relation to age is increasing in men, but decreasing in women. The level of Se in relation to age increases regardless of sex. Concentrations of Zn rise with age in women group, only. Positive correlation was found between BMI and level of Cu only for group of men. For Se levels and BMI differences exist only in men namely between groups <20 and >35 (82 microg Se.l(-1) vs. 92 microg Se.l(-1)). Slight positive correlations exist between Zn concentration and BMI in women only. The significant differences were found between smokers and non-smokers for Cu in men (850 microg Cu.l(-1) vs. 830 microg Cu.l(-1)) and Se (81 microg Se.l(-1) vs. 84 microg Se.l(-1)). The smoking has not significant influence on concentration of Zn in the blood. The hormonal contraception significantly increases the concentration of Cu in blood (920 microg Cu.l(-1) vs. 1,270 microg Cu.l(-1), p<0.01). The levels of Se and Zn in blood are not influenced using hormonal contraception.

Knowledge of normal levels of concentrations of trace elements (Cd, Cr, Cu, Hg, Pb, Se and Zn) in the population serve, among others, in the designing of regulations of exposure limits and prevention of diseases caused by deficiency in essential trace elements. Concentrations of the named elements in the hair of children in the Czech population were determined by means of atomic absorption spectrometry. The samples of hair were collected during 1994- 2001 from 3,556 children (1,741 boys and 1,815 girls, average age 9.9 years). Mineralization in a microwave digestion system was used following a washing procedure. The accuracy of results was checked by means of the control materials CRM Human Hair GBW 07601. Values of concentrations of the trace elements in hair found for children were (in medians) 0.14 microg Cd.g(-1), 0.22 microg Cr.g(-1), 12 microg Cu.g(-1), 0.19 microg Hg.g(-1), 1.6 microg Pb.g(-1), 0.22 microg Se.g(-1) and 124 microg Zn.g(-1), respectively. Statistically significant differences between boys and girls were found for Cd, Cu and Zn. Concentrations of the elements under study correspond to the published values for the non-exposed population.

Knowledge of normal levels of concentrations of trace elements (Cd, Pb, Hg, Cu, Zn, and Se) in the population serves, among others, in design of regulations concerning health protection, determination of exposition limits and prevention of diseases caused by deficiency of trace elements. Concentrations of the named elements in urine of the Czech population were determined by means of atomic absorption spectrometry. The urine has been collected during 1996-2000 from 1192 individuals (816 males and 376 females, average age 34.6 years) and 2008 children (1052 boys and 956 girls, average age 9.9 years). Mineralization in a microwave digestion system was used in sample preparation. The accuracy of results was checked by means of the Control Materials Seronorm 403,125 and BioRad 69,041. Values of concentrations of the trace elements in urine found for adult (medians) were 0.36 microgram Cd.g-1 creatinine, 10.6 micrograms Cu.g-1 creatinine, 0.68 microgram Hg.g-1 creatinine, 3.3 micrograms Pb.g-1 creatinine, 6.2 micrograms Se.g-1 creatinine, and 397 micrograms Zn.g-1 creatinine, respectively. Statistically significant differences between men and women have been found in the concentrations of Cu and Hg. In the juvenile population following concentrations have been found: 0.29 microgram Cd.g-1 creatinine, 16.1 micrograms Cu.g-1 creatinine, 0.32 microgram Hg.g-1 creatinine, 4.8 micrograms Pb.g-1 creatinine, 10.2 micrograms Se.g-1 creatinine and 460 micrograms Zn.g-1 creatinine. Statistically significant differences between boys and girls were found only in Cu and Hg concentrations. Concentrations of the studied elements correspond to the published values concerning population not exposed professionally.

The retrospective study evolution of trends in concentrations of Cd, Pb, Cu and Se in the population of the Czech Republic over 30 years period could be useful in design of regulations concerning health protection, prevention of diseases caused by deficiency of trace elements and have considerable economic importance. Concentrations of the named elements in the serum were determined by means of atomic absorption spectrometry (AAS) after mineralisation in a microwave digestion system. The 1433 samples of serum (730 males and 703 females, average age 48.7 and 49.1 years respectively) from a time period 1970-1995 were obtained from the Serum bank of National Institute of Public Health and volunteers (1999). Serum samples from the years 1970, 1975, 1980, 1985, 1990, 1995 and 1999 were examined. The accuracy of the results was checked by means of the Control material Seronorm Whole Blood 404,107 and Seronorm Serum 704,121, Nycomed. The concentration of Cd had a decreasing trend for the years 1975-1999 (0.82 microgram Cd.l-1 vs 0.47 microgram Cd.l-1). The levels of Pb are falling in the interval 1970-1980 (15.6 micrograms Pb.l-1 vs. 6.6 micrograms Pb.l-1). In year 1985 concentration of Pb increased (10.7 micrograms Pb.l-1) but subsequently decreased again (1995--6.4 micrograms Pb.l-1). In year 1999, it was 8.9 micrograms.l-1. The concentration of Cu decreased in period 1970-1990 (1525 micrograms Cu.l-1 vs. 990 micrograms Cu.l-1). From 1990 to 1999 the levels of Cu had an increasing tendency (1999--1060 micrograms Cu.l-1). Levels of Se in the interval 1970-1985 were surprisingly equal (58.1 micrograms Se.l(-1)-54.4 micrograms Se.l-1). However in the interval 1986-1990 the level of Se sharp declined (38.3 micrograms Se.l-1). Since 1990 levels of Se in serum increased again, up to 67.1 micrograms Se.l-1 in 1999. Statistically significant differences between men and women were found only in Cu and Pb concentrations. Concentrations of under study elements corresponded to the published values concerning unexposed population.

Knowledge of normal levels of concentrations of trace elements (Cd, Pb, Hg, Cu, Zn, and Se) in the population serves, among others, in design of regulations concerning health protection, determination of exposure limits and prevention of diseases caused by deficiency of trace elements. Concentrations of the named elements in whole blood of the Czech population were determined by means of atomic absorption spectrometry. The blood was collected during 1996-1998 from 1,216 blood donors (896 males and 320 females, average age 33 years) and 758 children (397 boys and 361 girls, average age 9.9 years). Mineralisation in a microwave digestion system was used in sample preparation. The accuracy of results was checked by means of the Control material Seronorm Whole Blood 404107 and Seronorm Serum 704121, Nycomed. Values of concentrations of the trace elements in blood found for adult (medians) were 0.7 microgram Cd.l-1, 800 micrograms Cu.l-1, 0.78 microgram Hg.l-1, 41 micrograms Pb.l-1, 76 micrograms Se.l-1, and 5,800 micrograms Zn.l-1, respectively. Statistically significant differences between men and women have been found in the concentrations of Cu, Hg, Pb, and Zn. In the juvenile population following medians of concentrations have been found: 0.15 microgram Cd.l-1, 1,047 micrograms Cu.l-1, 0.46 microgram Hg.l-1, 34 micrograms Pb.l-1, 69 micrograms Se.l-1, and 8,180 micrograms Zn.l-1. Statistically significant differences between boys and girls were found only in Pb and Zn concentrations. Concentrations of the studied elements correspond to the published values concerning population not exposed professionally.

The sensation of adequate taste detection can be associated with satisfaction of food intake. The impairment of taste detection may be associated with the development of obesity. Taste detection is determined hereditarily, but it can be influenced also by the occurrence of neuropathy. To find an explanation for these phenomena, we investigated 73 patients with diabetes mellitus (DM) 2 (i.e., non-insulin-dependent DM); 11 patients with DM 1 (i.e., insulin-dependent DM); 12 obese patients (body-mass index >30) without DM; and 29 control patients. All subjects underwent electrogustometric examination with Hortmman's electrogustometer. During this examination, we obtained electrical thresholds of taste by stimulating appropriate parts of the tongue. We stimulated the apex, middle, and near tongue radix areas on both sides. The resulting value is the average on the left and right sides of the mentioned areas. We considered a value of less than 40 microA to be normal. Values in excess of 100 microA are considered as hypogeusia. Values between 40 and 100 microA are taken as borderline, and ageusia is in excess of 500 microA. According to these criteria, in the DM 2 group, we found 40% of patients with hypogeusia, whereas in the DM 1 group, we found 33% of patients; 25% of patients were in the obese group. Among normal subjects (people without obesity or DM), no hypogeusia was found. We found ageusia in 5% of patients with DM 2, in 3% of patients with DM 1, and in 14% of obese patients. Among normal subjects, we found no ageusia. These results support the hypothesis that diminished taste detection can evoke hyperphagia and later obesity.

The biological monitoring of toxic and essential metals in biological material is important for the study of influence of environmental conditions on the human body. In this work, the determination of Cd, Pb and Hg in blood, urine and hair of children has been performed by atomic absorption spectroscopy. The electrothermal atomisation with Zeeman background correction was used for Pb and Cd determination and mercury was determined using Trace Mercury Analyser TMA 254. Methylmercury in hair was determined simultaneously. To check the method, SRM Lyphochek Urine Metal control--Biorad, Seronorm Trace Elements--Nycomed and GWB Human Hair (China) were used. The group of more than 100 children were chosen for the study. Statistical tests were used for the evaluation of the obtained results. The concentrations of all elements in all types of samples correspond to the "normal contents" published for the non-exposed population.

The biological monitoring of essential metals in blood, urine and hair became important for the control of biological processes and for the study of the influence of environmental conditions on the human organism. To determine the normal level of copper and zinc in the children population group of Central Bohemia (Benesov), 98 samples of whole blood, 133 samples of urine and 135 samples of hair have been analysed by means of atomic absorption spectroscopy. The mineralisation of blood and hair samples in the microwave oven and 3-fold dilution of urine were used for the sample preparation. Arithmetic and geometric means as well as median and ratio Zn/Cu were calculated. The concentration of the elements under study in all samples did not differ from the values published in the literature. Some differences between girls and boys have been found.