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This article reports on a capacity building partnership between The University of Georgia and the higher education system of Tunisia that has been ongoing since 2002. The article discusses important aspects of the program, highlights the conceptual framework and underlying principles that have guided and shaped its design, and gives a comprehensive overview of its overall objectives, concrete actions, and outcomes. Our team’s response to Tunisia’s most urgent development needs; integrating institutional and national resources; building networks of decision makers, administrators, faculty, and students across disciplinary and institutional boundaries; and facilitating the development of indigenous expertise were among the attributes leading to the program’s selection for the Andrew Heiskel Award for Innovation in International Education.

Women in STEM study and work in male-dominated environments with cultures based on masculine values and white male primacy. STEM women strain to conform to these cultures, and any failure to properly advance is often blamed on them. The struggles these women face and the impact on their psychological well-being and professional STEM lives remain mostly untold. The Global Women in STEM Leadership Summit (GWiS) is a multigenerational, multi-sector conference that, among other things, empowers women in STEM to explore and articulate their struggles in male-dominated study and work cultures, to discuss how these experiences hinder their progress and affect their well-being, and to recognize their unique contributions. This paper leverages data collected at the 2019 GWiS to (1) expose, amplify, validate and elevate the severely underrepresented female identity and perspective in STEM, (2) reveal struggles women in STEM face and uncover underlying root causes in male practices that hinder women in STEM, and (3) illustrate the value of counterspaces, such as GWiS, in validating women's identities and perspectives, creating empowering experiences, and countering negative feelings. If widely implemented, this shift in perspective is the first step toward dismantling one-sided systems and co-creating more balanced work environments that benefit all. [ABSTRACT FROM AUTHOR]

The hop variety Sorachi Ace was bred and first licenced in Japan by Sapporo Breweies Ltd. in 1984. Recently, this hop has been used as a 'flavour hop' to give beer a unique characteristic aroma, for example, woody, pine-like, citrus, dill-like and lemon grass-like. In previous study, we identified geranic acid as one of the unique compounds comprising Sorachi Ace. As a result of model sensory evaluations, we reported that geranic acid itself had little flavour, but that this compound could enhance the flavour intensities of other hop-derived flavour compounds in spite of its very low flavour intensity. In this study, the mechanism of Sorachi Ace varietal aroma was further investigated using sensory omission test. The selected 16 compounds were separated to five groups, 'carboxylic acids', 'alcohols', 'aldehydes', 'esters', and 'hydrocarbons'. As a result of the omission test, it was concluded that all groups could affect to the varietal aroma of Sorachi Ace, despite the concentrations of several compounds were at very low levels. In addition, an effect of blend-hopping with Sorachi Ace and other flavour hop varieties was investigated. It was surprisingly found that blend-hopping between Sorachi Ace and certain hop varieties (Kazbek, Hallertau Blanc, and Cascade) could negatively affect to the flavour impression of test-beers. On the other hand, blend-hopping between Sorachi Ace and Citra or Mosaic could positively affect to the flavour impression of test-beers. Because of high concentrations of 4-Methyl-4-sulfanylpentan-2-one (4MSP) derived from these hops, it is assumed that 4MSP containing hops could be effective choice for blending with Sorachi Ace. [ABSTRACT FROM AUTHOR]

We successfully developed new automated 'FCT (Foam Collapse Time)' system for the evaluation of visual foam stability in order to get a useful knowledge for improving practical foam stability. The FCT value is defined as the required time for a reduction of the 40 % of glass hight (32 mm) of foam layer to a single layer in a prescribed glass. The improved FCT pouring apparatus was coupled with automated turntable for 6 glasses, electronic balance, and CCD-cameras (side and upper) for measuring the foam layer (mm) and the collapse point. Based on automatically collected data, the FCT value could be statistically calculated by specialized software on the control PC. Using this system, we confirmed an importance of hop bitter acids and their derivatives, which could affect the strength of foam membrane, for visual foam stability evaluating by FCT. From comparison between FCT, Sigma, and NIBEM methods, it was suggested that detectability for foam membrane strength was more sensitive in FCT and NIBEM than Sigma, and that foam membrane strength could also affect foam lacing. [ABSTRACT FROM AUTHOR]

The successful implementation of a transmission level Harmonic Measurement System requires accurate and reliable measurement of harmonic voltages and currents. Existing substation instrument transformers are designed for 60 Hz measurements and they have been shown to cause resonance errors in the measurements. In this paper, we propose an on-line error correction method to correct for these resonance errors as well as possible saturation errors. The error correction is formulated as an output tracking problem where the distorted measurements are used along with the experimentally developed transformer model to reconstruct the transformer input. The method is generic, thereby permitting its use with any measurement system that utilizes a transducer with nonideal properties. It is also cost effective since it can be implemented on a personal computer or a digital signal processing chip.

Bioprocesses are highly nonlinear and they operate within a wide range of operating regimes. Proper modeling and control of these processes necessitate real-time identification of these regimes. In this paper, we introduce an approach for the development of a fuzzy neural network (NN) model for a bioprocess based on decomposition of the process into its different regimes. The model consists of multiple linear local models, one for each regime, and its output is the interpolation of the outputs from the local models. Regime identification is performed using fuzzy clustering and NNs. The outcome of this identification technique is a set of membership functions which indicate to what degree the process is governed by the three operating regimes at any given point in time. The method is illustrated through the development of a real-time product estimation model for a simulated gluconic acid batch fermentation. Index Terms--Bioprocess, fuzzy clustering, modeling, multiple operating regimes, neural networks.

Real-time control is becoming an integral part of modern machine systems for high-quality agricultural production. Maintaining consistently high-quality agricultural production while keeping up with growing labor shortages is a challenge. Providing a work place for laborers which meets increasingly rigorous safety requirements and environmental constraints is likewise a challenge. More appropriate energy management and soil management have also motivated real-time control applications. Appropriate sensing and control systems can reduce labor requirements, function in difficult environments, and allow vehicles to adapt to varying soil chemical and physical states. Labor shortages and environmental constraints coupled with the reality of spatial variability of chemical and physical properties among and within agricultural production areas readily explain the migration toward real-time control of agricultural equipment. This paper presents a review of the most recent advances in the development of sensors and controllers for agricultural applications. Index Terms--Controllers, robotic farming, sensors.

Successful implementation of a transmission level harmonic measurement system requires accurate and reliable measurement of harmonic voltages and currents. Existing substation instrument transformers are designed for harmonic-free 60 Hz measurements. Hence, their use to measure harmonics leads to the introduction of resonance as well as saturation errors in the measurements. An on-line error correction method to correct for wound-type potential transformer measurement errors has been proposed in previous publications. The error correction was formulated as an output tracking problem where the distorted measurements were used along with the experimentally developed transformer model to reconstruct the transformer input. The scope of this paper is to develop a sensitivity analysis for the error correction method with respect to the transformer parameters. Results of this analysis indicate that the sensitivity of the method with respect to the transformer parameters is quite low. Index Terms--Transformer, error, correction, sensitivity.

Traditional environmental control methods for poultry housing which rely solely on environmental factors fall short in meeting thermal and physiological needs of the animals. New methods are needed that factor in the physiological needs and responses of the animals in order to maximize well-being of the animals and minimize heat stress. Deep body temperature (DBT) has been shown in the literature to be a strong indicator of heat stress, therefore studies are needed that help us gain a deeper understanding of the relationship between this variable and environmental conditions. The aim of this study was to identify the order of the dynamic response of poultry DBT to large step changes in ambient temperature (AT). Temperature steps had to be big enough to take the chickens out of their homeothermic zone. A total of 46 DBT/AT data sets with 23 upward AT steps and 23 downward AT steps were obtained using a biotelemetry system, and involving three chickens. DBT responses of individual chickens to step changes in AT were found to have a 0.88 average Pearson correlation suggesting consistency in chickens' responses to the same stimuli (p<0.0005). The data indicated that DBT responses to AT followed a first order behavior in most cases with an average time constant of 1.6 h, and the curve fitting method was used to validate this observation. There was a 0.88 average correlation between DBT model and measured data (p<0.0005). These results indicate statistical significance in the data used and the model derived from it. In conclusion, it is reasonable to assume that the dynamic response of poultry DBT to large step changes in ambient temperature follows a first order model. Although further studies are needed to more fully derive the model, this study provided a stepping-stone towards gaining a better understanding of the relationship between DBT and AT, therefore taking us one step closer towards making optimal management and risk assessment decisions that are based on physiological needs of the chickens. [ABSTRACT FROM AUTHOR]

This article reports on a capacity building partnership between The University of Georgia and the higher education system of Tunisia that has been ongoing since 2002. The article discusses important aspects of the program, highlights the conceptual framework and underlying principles that have guided and shaped its design, and gives a comprehensive overview of its overall objectives, concrete actions, and outcomes. Our team's response to Tunisia's most urgent development needs; integrating institutional and national resources; building networks of decision makers, administrators, faculty, and students across disciplinary and institutional boundaries; and facilitating the development of indigenous expertise were among the attributes leading to the program's selection for the Andrew Heiskel Award for Innovation in International Education. [ABSTRACT FROM AUTHOR]

This paper reports on four microcontroller-based courses developed at the University of Georgia for a broad multidisciplinary undergraduate and graduate student body. The courses are Introduction to Robotics, Embedded Systems, Introduction to Microcontrollers, and Advanced Microcontrollers. These courses, which are taught in a hands-on manner, equip students with the necessary tools and know-how to make use of the powerful technology of microcontrollers within their own disciplines. This paper addresses some of the challenges encountered due to the diverse student backgrounds and how these challenges are met through various pedagogical methods such as teamwork, achieving the right balance between theory and practice, and giving students from various disciplines an 'industry-like' experience. [ABSTRACT FROM AUTHOR]

Hops are among the most important ingredients in beer that contribute to beer flavor. Consequently, novel types of hops have been bred and widely used worldwide. For example, the Sorachi Ace hop imparts characteristic varietal aromas, including woody, pine-like, citrus, dill-like, and lemongrass-like aromas, to the finished beer. In our previous study, the unique volatile compound geranic acid was significantly detected only in the test beer brewed with the Sorachi Ace hop; moreover, the coexistence of geranic acid and other hop-derived flavor compounds could result in the characteristic aroma of the Sorachi Ace beers. In this study, selected hop-derived flavor compounds, including geranic acid, were compared among 17 hop varieties. The geranic acid content in the Sorachi Ace hop was the highest among the studied hops. We also investigated the behavior of geranic acid and related flavor compounds throughout the fermentation process. The content of geranic acid was higher than those of the other compounds during fermentation. Next, we compared the concentrations of these compounds in kettle-, late-, and dry-hopped beers using Sorachi Ace hop. The results revealed that geranic acid remained at higher concentrations from the worts to finished beers despite the decrease in the content of other hop-derived flavor compounds as a result of evaporation and/or other factors during brewing. Further, geranic acid could remain at high levels in the test-brewed beers with Sorachi Ace hops because of its behavior as an acid throughout the brewing process, including during wort boiling and fermentation.

Background: Flavor hops (Humulus lupulus L.) are recognized as key raw materials that impart unique flavors to beer, especially in the emerging craft-beer industry. In this study the sensory evaluation of hop cone aromas using hop water extract by boiling (HWEB) was applied to develop new flavor hop cultivars in a screening from tens of varieties and breeding lines., Results: The sensory scores of HWEB showed a significant correlation with polyfunctional thiol content in hop cones, including substances such as 4-methyl-4-sulfunylpentan-2-one (4MSP) and 3-sulfunyl-4-methylpentan-1-ol (3S4MP), which are known to be difficult to analyze mechanically. As a result of the sensory evaluation of HWEB, a breeding line, 'K906901060' was found to have a strong fruity note. Subsequent chemical analyses revealed that this cultivar had 80-136 μg kg -1 of 4MSP in its cones, which is similar to the concentration present in current leading flavor hop cultivars, such as Citra (37-114 μg kg -1 ) and Simcoe (2-112 μg kg -1 ). Beer late-hopped with K906901060 provoked a greater tropical flavor impression than beer hopped using Nelson Sauvin hops., Conclusion: The sensory evaluation of HWEB was indicated to be useful to search for hops containing polyfunctional thiols. The plant was registered, as 'Furano K906901060 Go' in Japan, in the EU, and in the USA, and the cultivar was given the commercial name 'Furano Magical'. This cultivar was derived from a cross performed in 1989 and had been kept as a mid-mother plant from 1997, until being selected in 2014, as described here. © 2022 Society of Chemical Industry., (© 2022 Society of Chemical Industry.)

In recent years, many hop varieties with unique aromas, so-called "flavor hops", have been bred and grown. Here, we investigated the effect of late-harvested hops using three flavor hop varieties; Furano Beauty, Furano Magical, and Cascade. The sample hops were harvested at different days after flowering (DAF): DAF 45 (normal harvest), DAF 65, DAF 75, and DAF 85. We measured the volatile thiols in sample cones. The results indicated that 4-methyl-4-sulfanylpentane-2-one contents showed almost no change or a slightly decrease with a delay in harvest, whereas 3-sulfanyl-4-methylpentan-1-ol (3S4MP) content in late-harvested samples increased several fold in comparison with normal-harvested samples. Additionally, 3S4MP contents in the beers brewed with DAF 65 samples were several times higher than those using DAF 45 ones. From these results, we propose a new method to control 3S4MP content in hop cones by changing its harvest date.

Hops are natural ingredients used to impart bitterness and flavor to beer. Recently, new varieties of hops have attracted global research attention. The Sorachi Ace variety, in particular, interests many craft brewers. This hop imparts characteristic varietal aromas, including woody, pine-like, citrus, dill-like, and lemongrass-like, to finished beers. Here, we investigated specific flavor compounds derived from Sorachi Ace using selectable one-dimensional or two-dimensional gas chromatography-olfactometry/mass spectrometry and head space-solid phase microextraction-gas chromatography-mass spectrometry. The results showed that a unique volatile compound, geranic acid, was present at a significant level only in the test beer brewed with the Sorachi Ace hop. Furthermore, sensory evaluation techniques revealed that geranic acid has very unique characteristics. This compound is not odor-active but functions as an enhancer for hop-derived terpenoids at subthreshold levels.

A method for the quantitation of six polyfunctional thiols, 4-methyl-4-sulfanylpentan-2-one (4MSP), 3-sulfanyl-4-methylpentan-1-ol (3S4MP), 3-sulfanyl-4-methylpentyl acetate (3S4MPA), 3-sulfanyl-3-methylbutan-1-ol (3S3MB), 3-sulfanylhexan-1-ol (3SH), and 3-sulfanylhexyl acetate (3SHA), in hops and beer without organic mercury compounds was developed. The method employed specific extraction of thiols using a silver ion solid phase extraction (SPE) cartridge and gas chromatography-tandem mass spectrometry (GC-MS/MS). For all thiols analyzed, good linearity was achieved by adding thioglycerol as an analyte protectant. Recoveries for both hops (74-100%) and beer (79-113%) were acceptable, and the repeatability for both was also good (relative standard deviations of 2.8-8.4%). The limits of detection for the six polyfunctional thiols were below their odor thresholds in beer. The method was applied to quantitation of hops and beer flavored with thiol-containing hop varieties. Due to their detected levels and level variations in different beers, 4MSP and 3S4MP are thought to be important polyfunctional thiols for the characteristic flavor of hop varieties.

It is well-known that various beers contain many flavor compounds derived from barley malts, hops, yeast fermentation, and other raw materials. Among these flavor compounds, terpenoids are mainly derived from hops. Linalool, one of the monoterpene alcohols, has been found in various beers and been regarded as an important factor for a hop-derived beer flavor. We focus on contributions of other monoterpene alcohols (geraniol, beta-citronellol, nerol, and alpha-terpineol) to hopped beer flavor. Several researchers have reported that monoterpene alcohols are biotransformed by yeast and that geraniol is mainly transformed to beta-citronellol during the first 2-4 days in model fermentation. In this study, we investigated the biotransformation of monoterpene alcohols during fermentation of hopped beer by using various hop cultivars. As a result, geraniol drastically decreased during the first 3 days. beta-Citronellol was almost absent in wort and gently increased during the total fermentation period. The concentrations of geraniol and beta-citronellol in finished beer increased, depending on the initial concentration of geraniol in the wort. The continuous increase of beta-citronellol did not correspond to the fast decrease of geraniol. This increase of beta-citronellol might be partly explained by an occurrence of glycosidically bound flavor precursor and a glucoside hydrolase activity secreted from lager yeast. In addition, we examined flavor characteristics of monoterpene alcohols and found that there was an additive effect among linalool, geraniol, and beta-citronellol and that only 5 microg/L of geraniol and beta-citronellol were enough for this effect. Therefore, it is suggested that not only linalool but also geraniol and beta-citronellol might contribute to hopped beer flavor at lower levels, at which OAVs of these compounds become below 1.0.

Nelson Sauvin (NS) is a unique hop cultivar that was bred and grown in New Zealand. This hop gives a specific flavor (exotic fruit-like, white wine-like) to finished beers. However, the key compounds of this flavor have not yet been identified. We have attempted to identify the specific flavor compounds derived from NS. We focused on certain volatile thiols that are well-known to contribute to wine flavors, especially Sauvignon Blanc. The product made from NS (NS product) lost its specific flavor by contact with copper. Copper is well-known as an absorber of thiols in the field of wine flavor investigations. Therefore, it might point to the existence of thiols. We analyzed the NS product by GC-FPD, GC-olfactometry and GC-MS, and identified two new volatile thiols, 3-sulfanyl-4-methylpentan-1-ol (3S4MP), and 3-sulfanyl-4-methylpentyl acetate (3S4MPA). These compounds have a grapefruit-like and/or rhubarb-like odor, similar to that of Sauvignon Blanc. We quantified these compounds in the NS products and determined their thresholds. As a result, 3S4MP contained about 2-fold of its threshold in beers, and 3S4MPA was included below its threshold. However, it was confirmed that 3S4MP enhanced the flavors of 3S4MPA by synergy. Therefore, we concluded that both of the new volatile thiols would contribute to the specific odor of beers produced with NS.

Foam stability is an important quality trait of beer. Our previous results of two-dimensional gel electrophoresis (2DE) analyses of beer proteins implied a relationship between barley dimeric alpha-amylase inhibitor-1 (BDAI-1) and beer foam stability as judged by the NIBEM-T analyzer. To develop a novel prediction method of beer foam stability under different conditions of barley cultivar and malt modification, multiple linear regression analysis was applied. The spot intensities of major beer proteins on 2DE gel were quantified and used as explanatory variables. The foam stabilities of 25 beer samples each brewed from malt with different malt modification in one of the three cultivars (cultivars A, B, and C) were explained by the spot intensities of BDAI-1 at the 5% significance level ( r = 0.421). Furthermore, two other major protein spots (b0 and b5) were observed on the 2DE gels of Japanese commercial beer samples with different foam stability. Then, multiple regression for foam stability was calculated using these three spot intensities as explanatory variables. As a result, 72.1% of the beer foam stability in 25 beer samples was explained by a novel multiple regression equation calculated using spot b0 and BDAI-1 as positive explanatory variables and spot b5 as a negative variable. To verify the validity of the multiple regression equation and the explanatory variables, the beer foam stability in practical beer samples was analyzed. As a result, 81.5% of the beer foam stability in 10 Japanese commercial beer samples was also explained by using spot b0 and BDAI-1 as positive explanatory variables and spot b5 as a negative variable. Mass spectrometry analyses followed by database searches revealed that protein spots b0 and b5 were identified as protein Z originated from barley and thioredoxin originated from yeast, respectively. These results confirm that BDAI-1 and protein Z are foam-positive factors and identify yeast thioredoxin as a possible novel foam-negative factor.

The foam stability of beer is one of the important key factors in evaluating the quality of beer. The purpose of this study was to investigate the relationship between the level of malt modification (degradation of protein, starch, and so on) and the beer foam stability. This was achieved by examining foam-promoting proteins using two-dimensional gel electrophoresis (2DE). We found that the foam stability of beer samples brewed from the barley malts of cultivars B and C decreased as the level of malt modification increased; however, the foam stability of cultivar A did not change. To identify the property providing the increased foam stability of cultivar A, we analyzed beer proteins using 2DE. We analyzed three fractions that could contain beer foam-promoting proteins, namely, beer whole proteins, salt-precipitated proteins, and the proteins concentrated from beer foam. As a result, we found that in cultivar A, some protein spots did not change in any of these three protein fractions even when the level of malt modification increased, although the corresponding protein spots in cultivars B and C decreased. We analyzed these protein spots by peptide mass finger printing using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. As a result, all of these spots were identified as barley dimeric alpha-amylase inhibitor-I (BDAI-I). These results suggest that BDAI-I is an important contributor to beer foam stability.