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Faith leaders can be uniquely positioned to guide and support young people on health issues, particularly HIV/AIDS and sexual violence. Faith Matters!, a 2-day training workshop for faith leaders, was delivered in September 2021 in Zambia. Sixty-six faith leaders completed a questionnaire at baseline, 64 at posttraining, and 59 at 3-month follow-up. Participants' knowledge, beliefs, and comfort communicating about HIV/AIDS and sexual violence were assessed. More faith leaders accurately identified common places where sexual violence occurs at the 3-month point compared to baseline: at church (2 vs. 22, p = .000), the fields (16 vs. 29, p = .004), parties (22 vs. 36, p = .001), and clubs (24 vs. 35, p = .034). More faith leaders stated that they engaged in conversations that supported people living with HIV (48 at baseline vs. 53, p = .049 at 3-month follow-up). These findings can inform future HIV/AIDS initiatives focusing on increasing the capacity among communities of faith.

Military activities can contaminate productive land with potentially toxic substances. The most common trace metal contaminant on military bases is lead (Pb). A field experiment was begun in 2016 at Fort Riley, KS, in an area with total soil Pb concentrations ranging from 900 to 1,500 mg kg -1 and near-neutral pH. The main objectives were to test the potential of Miscanthus sp. for phytostabilization of the site and to evaluate the effects of soil amendments on Miscanthus growth, soil-plant Pb transfer, bioaccessibility of soil Pb, and soil health. The experimental design was a randomized complete block, with five treatments and four replications. Treatments were (a) existing vegetation; (b) Miscanthus planted in untilled soil, no amendments; (c) Miscanthus planted in tilled soil; (d) Miscanthus planted in tilled soil amended with inorganic P (triple superphosphate applied at 5:3 Pb:P); and (e) Miscanthus planted in tilled soil amended with organic P (Class B biosolids applied at 45 Mg ha -1 ). Tilling and soil amendments increased dry matter yields only in the establishment year. Total Pb uptake, plant tissue Pb concentration, and soil Pb bioaccessibility were significantly less in the Miscanthus plots amended with biosolids than the Miscanthus plots with no added P across all 3 yr. Enzyme activities, organic carbon, and microbial biomass were also greater in biosolids-treated plots. Results show that planting-time addition of soil amendments to Pb-contaminated soil supported Miscanthus establishment, stabilized and reduced bioaccessibility of soil Pb, reduced concentration and uptake of Pb by Miscanthus, and enhanced soil health parameters., (© 2021 The Authors. Journal of Environmental Quality published by Wiley Periodicals LLC on behalf of American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America.)

The aim of this study was to develop a nanoparticle-based cell capture system combined with a lateral flow test strip (LFT) assay for rapid detection of Campylobacter jejuni from poultry samples. The developed assay was bench-marked against the standard modified Charcoal Cefoperazone Deoxycholate Agar (mCCDA) method according to ISO16140:2003 procedures. The synthesized ferromagnetic nanoparticles (FMNs) were modified with glutaraldehyde, then functionalized with polyclonal antibodies for specific C. jejuni capture and concentration from poultry samples. After lysing captured cells, DNA from C. jejuni was amplified by PCR using the primers designed to target the hipO gene, and the PCR amplicons were detected with the lateral flow test strip assay. Following the ISO16140:2003 guidelines, the relative detection limit, and the inclusivity and exclusivity tests were determined. The results showed that the limit of detection (LOD) of the assay was 10 0 or 1 cfu/ml with C. jejuni in pure culture and 10 1 -10 2  cfu/ml with target cells spiked in poultry sample. In addition, the inclusivity and exclusivity tests were found to be 100%. Using field chicken samples (n = 60), the assay showed relative accuracy, relative specificity, and relative sensitivity of 96.67%, 100% and 93.33%, respectively. The positive predictive values (PPV) and negative predictive values (NPV), and the kappa index of concordance (k) were calculated as 100% and 93.75%, and 0.93, respectively. The developed assay required approximately 3 h to complete and gave results comparable to those analyzed by the standard culture method, which required 5-7 days. The assay is rapid, easy-to-use, and has potential to be directly applied to C. jejuni detection in various categories of poultry samples., (Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.)

There are many good reasons to promote sustainable development and reduce greenhouse gas emissions and other combustion emissions. The air quality in many urban environments is causing many premature deaths because of asthma, cardiovascular disease, chronic obstructive pulmonary disease, lung cancer, and dementia associated with combustion emissions. The global social cost of air pollution is at least $3 trillion/year; particulates, nitrogen oxides and ozone associated with combustion emissions are very costly pollutants. Better air quality in urban environments is one of the reasons for countries to work together to reduce greenhouse gas emissions through the Paris Agreement on Climate Change. There are many potential benefits associated with limiting climate change. In the recent past, the concentrations of greenhouse gases in the atmosphere have been increasing and the number of weather and climate disasters with costs over $1 billion has been increasing. The average global temperature set new record highs in 2014, 2015, and 2016. To reduce greenhouse gas emissions, the transition to electric vehicles and electricity generation using renewable energy must take place in accord with the goals of the Paris Agreement on Climate Change. This work reviews progress and identifies some of the health benefits associated with reducing combustion emissions., (© 2017 American Institute of Chemical Engineers Environ Prog, 36: 982-988, 2017.)

Introduction: The collaborations between dental care providers and other health care providers are especially needed for underserved populations. There is a deficit of research focused on underserved populations who utilize a safety net facility such as a free clinic in the United States. The purpose of this study is to examine the association between health-related beliefs and oral health behaviors among uninsured adults utilizing a primary care free clinic providing oral health care., Methods: Uninsured primary care patients utilizing a free clinic (N = 585) participated in a self-administered paper survey in May and June, 2016., Results: More than 60% of free clinic patients reported a perceived need for dental treatment. Free clinic patients who brush their teeth more than once a day reported better perceived general health compared with those who do not brush their teeth more than once a day. Free clinic patients who had perceived a need for dental treatment reported worse perceived general health compared to those who did not report dental needs., Conclusions: The results of this study indicate a pressing need for the further development of dental care services at safety-net clinics. By including dental care in health promotion programs, it will have positive impacts not only on oral health but also on a healthy lifestyle and the general health of underserved populations utilizing a safety-net clinic. The implementation and evaluation of the integrated health programs, which include primary care and oral health care together, would be beneficial to reduce oral health disparities.

Objectives: Oral health-related quality of life (OHRQoL) is an important health indicator not only for individuals but also for oral health care providers to treat a person holistically. Previous studies focused on OHRQoL do not provide comprehensive knowledge regarding low-income patients in the United States, many of whom have chronic health conditions that can affect their oral health. The purpose of this study is to examine factors associated with OHRQoL among low-income, uninsured patients of safety-net providers, which provide free or reduced fee medical and/or dental care to underserved populations., Methods: Uninsured patients (N = 584) participated in a self-administered survey in May and June 2016 at a safety-net clinic in the United States serving a low-income uninsured population, which provides limited oral health care services. This study used cross-sectional design and a nonprobability sample. The dependent variable was OHRQoL measured using the Oral Health Impact Profile-14. Chi square tests, Analysis of Variance tests, and multiple regression were used for statistical analysis., Results: Higher levels of dental care neglect and lower frequency of oral hygiene practice were associated with lower levels of OHRQoL (P < 0.01). Participants utilizing a diabetes clinic reported better OHRQoL than those who were not patients of a diabetes clinic (P < 0.05). US born English speakers had worse general health and OHRQoL compared to non-US born English speakers and Spanish speakers (P < 0.01)., Conclusions: An intervention to remedy dental neglect is recommended to improve OHRQoL among uninsured safety-net patients., (© 2016 American Association of Public Health Dentistry.)

Constructed wetland treatment systems are used to remove selenium (Se) from flue-gas desulfurization (FGD) wastewater (WW). However, direct confirmation of the mechanism responsible for FGD WW Se retention in soil is lacking. A laboratory-based soil column study was performed to develop an evidence-based mechanism of Se retention and to study the behavior and the retention capacity of FGD WW constituents in water-saturated soil. A deoxygenated 1:1 mixture of FGD WW and raw water was delivered to the columns bottom-up at a flux of 1.68 cm d for 100 d. Some of the columns were flushed with the raw water at the same rate for an additional 100 d. Column effluent was analyzed for constituents of concern. Results showed a complete retention of FGD WW Se in the soil materials. Boron and fluorine were partially retained; however, sulfur, sodium, and chlorine retention was poor, agreeing with field observations. The FGD WW Se was retained in soil near the inlet end of the columns, indicating its limited mobility under reduced conditions. Sequential extraction procedure revealed that retained Se was mainly sequestered as stable/residual forms. Bulk- and micro-X-ray absorption near-edge structure spectroscopy confirmed that Se was mainly retained as reduced/stable species [Se(IV), organic Se, and Se(0)]. This study provides direct evidence for FGD WW Se retention in water-saturated soil via the transformation of oxidized Se into reduced/stable forms., (Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.)

The Paris Agreement on Climate Change has the potential to improve air quality and human health by encouraging the electrification of transportation and a transition from coal to sustainable energy. There will be human health benefits from reducing combustion emissions in all parts of the world. Solar powered charging infrastructure for electric vehicles adds renewable energy to generate electricity, shaded parking, and a needed charging infrastructure for electric vehicles that will reduce range anxiety. The costs of wind power, solar panels, and batteries are falling because of technological progress, magnitude of commercial activity, production experience, and competition associated with new trillion dollar markets. These energy and transportation transitions can have a very positive impact on health. The energy, transportation, air quality, climate change, health nexus may benefit from additional progress in developing solar powered charging infrastructure., Competing Interests: Conflict of Interest: All authors declare no conflicts of interest in this paper.

Studies were conducted in a Thai poultry plant to identify the factors that affected numbers of Campylobacter jejuni in chicken carcasses. The concentrations of Campylobacter were determined using the SimPlate most probable number and modified charcoal cefoperazone deoxycholate plating methods. Results indicated that the mean concentrations of C. jejuni in carcasses after scalding, plucking, and chilling were 2.93 ± 0.31, 2.98 ± 0.38, 2.88 ± 0.31, and 0.85 ± 0.95 log cfu, whereas the concentrations of C. jejuni in the scalding tank water, plucked feathers, and chicken breast portion were 1.39 ± 0.70, 3.28 ± 0.52, and 0.50 ± 1.22 log cfu, respectively. Sensitivity analysis using tornado order correlation analysis showed that risk parameters affecting the contamination of C. jejuni in the chicken slaughter and processing plant could be ranked as chilling water pH, number of pathogens in the scald tank water, scalding water temperature, number of C. jejuni on plucked feathers, and residual chlorine in the chill water, respectively. The exposure assessment and analysis of process parameters indicated that some of the current critical control points were not effective. The suggested interventions included preventing fecal contamination during transportation; increasing the scalding temperature, giving the scalding water a higher countercurrent flow rate; reducing contamination of feathers in the scalding tank to decrease C. jejuni in the scalding water; spraying water to reduce contamination at the plucking step; monitoring and maintaining the chill water pH at 6.0 to 6.5; and increasing the residual chlorine in the chill water. These interventions were recommended for inclusion in the hazard analysis and critical control point plan of the plant.

New technologies are not only critical in supporting traditional industrial and military success but also play a pivotal role in advancing sustainability and sustainable development. With the current global economic challenges, resulting in tighter budgets and increased uncertainty, synergistic paradigms and tools that streamline the design and dissemination of key technologies are more important than ever. Accordingly, a proactive and holistic approach can facilitate efficient research, design, testing, evaluation, and fielding for novel and off-the-shelf products, thereby assisting developers, end users, and other diverse stakeholders in better understanding tradeoffs in the defense industry and beyond. By prioritizing mechanisms such as strategic life-cycle environmental assessments (LCEA); programmatic environment, safety, and occupational health evaluations (PESHE); health hazard assessments (HHA); and other innovative platforms and studies early within systems engineering, various nonlethal military technologies have been successfully developed and deployed. These efforts provide a framework for addressing complex environment, safety, and occupational health risks that affect personnel, infrastructure, property, socioeconomic, and natural/cultural resources. Moreover, integrated, comprehensive, multidisciplinary, and iterative analyses involving flexible groups of specialists/subject matter experts can be applied at various spatiotemporal scales in support of collaborations. This paper highlights the Urban Operations Laboratory process utilized for inclusive and transformative environmental analysis, which can translate into advantages and progress toward sustainable systems., ((c) 2009 SETAC.)

Phytoremediation, the use of plants to clean up contaminated soil and water, has a wide range of applications and advantages, and can be extended to scientific education. Phytoremediation of textile dyes can be used as a scientific experiment or demonstration in teaching laboratories of middle school, high school and college students. In the experiments that we developed, students were involved in a hands-on activity where they were able to learn about phytoremediation concepts. Experiments were set up with 20-40 mg L(-1) dye solutions of different colors. Students can be involved in the set up process and may be involved in the experimental design. In its simplest forms, they use two-week-old sunflower seedlings and place them into a test tube of known volume of dye solution. Color change and/or dye disappearance can be monitored by visual comparison or with a spectrophotometer. Intensity and extent of the lab work depends on student's educational level, and time constraints. Among the many dyes tested, Evan's Blue proved to be the most readily decolorized azo dye. Results could be observed within 1-2 hours. From our experience, dye phytoremediation experiments are suitable and easy to understand by both college and middle school students. These experiments help visual learners, as students compare the color of the dye solution before and after the plant application. In general, simple phytoremediation experiments of this kind can be introduced in many classes including biology, biochemistry and ecological engineering. This paper presents success stories of teaching phytoremediation to middle school and college students.

The dermal absorption potential of a nanocrystalline magnesium oxide (MgO) and titanium dioxide (TiO(2)) mixture in dermatomed human skin was assessed in vitro using Bronaugh-type flow-through diffusion cells. Nanocrystalline material was applied to the skin surface at a dose rate of 50 mg/cm(2) as a dry powder, as a water suspension, and as a water/surfactant (sodium lauryl sulfate) suspension, for 8 hours. Dermal absorption of nanocrystalline MgO and TiO(2) through human skin with intact, functional stratum corneum was not detectable under the conditions of this experiment.

The degree of steak doneness is an important factor in providing consumers with a satisfying eating experience. Endpoint temperature and cooking rate are the determinants of degree of doneness. Our objectives were to predict internal temperature profiles and cooking times for longissimus lumborum and biceps femoris steaks. Each biceps femoris and longissimus lumborum steak was cooked individually in a gas-fired, forced-air-convection oven at 163 °C until the center temperature of each steak reached 70 °C. Temperature profiles were recorded by a Doric temperature recorder and the recorded time and temperature data were imported into a spreadsheet. A prediction method was then implemented to predict cooking times and temperature profiles. No significant differences (p<0.05) were found in cooking times between experimental and predicted values for either longissimus lumborum or biceps femoris steaks. Good agreement was found between experimental and predicted temperature profiles for the longissimus lumborum muscle. However, predicted temperature profiles were consistently higher (except for the beginning of the cooking cycle) than the experimental values up to 65 °C in the cooking cycle for biceps femoris steaks. A highly positive linear relationship was found between experimental and modeled temperature profiles for longissimus lumborum (R(2)=0.99), whereas a high quadratic (R(2)=0.99) relationship was found for biceps femoris steaks. Our method for predicting temperature profiles of steaks for a specified cooking time to attain a given degree of doneness should increase consumer satisfaction by reducing variation in meat sensory traits related to an expected degree of doneness.

This article describes a systematic approach to understanding the effect of environmental variables on plant uptake (phyto-uptake) of organic contaminants. Uptake (and possibly phytotransformation) of xenobiotics is a complex process that may differ from nutrient uptake. A specific group of xenobiotics (benzotriazoles) were studied using sunflowers grown hydroponically with changes of environmental conditions including solution volume, temperature, pH, and mixing. The response of plants to these stimuli was evaluated and compared using physiological changes (biomass production and water uptake) and estimated uptake rates (influx into plants), which define the uptake characteristics for the xenobiotic. Stirring of the hydroponic solution had a significant impact on plant growth and water uptake. Plants were healthier, probably because of a combination of factors such as improved aeration and increase in temperature. Uptake and possibly phytotransformation of benzotriazoles was increased accordingly. Experiments at different temperatures allowed us to estimate an activation energy for the reaction leading to triazole disappearance from the solution. The estimated activation energy was 43 kJ/mol, which indicates that the uptake process is kinetically limited. Culturing plants in triazole-amended hydroponic solutions at different pH values did not strongly affect the biomass production, water uptake, and benzotriazole uptake characteristics. The sunflowers showed an unexpected capacity to buffer the solution pH.

Vegetation is often used to clean up soils and groundwater contaminated with organic contaminants. Plant-induced upward water movement may draw organic contaminants spilled near the watertable to the more aerated near-surface soil. The objective of this study was to develop and verify a 1-D model of fate and transport of JP-8, a kerosene-based jet fuel, in soil. The modeling approach considered the advective and dispersive transport of jet fuels dissolved in groundwater, which may undergo simple first-order decay or linear adsorption. The governing partial differential advection dispersion equation was solved in one dimension. Data from an experiment of fate and transport of JP-8 with plant-induced upward water movement were used to verify the model. Simulated results with different scenarios described the experimental results well for different depths above the contaminated zone in both vegetated and unvegetated columns. Advection was the dominant mechanism near the contaminated zone and advection with retardation and decay was used to fit the data away from the contaminated zone. Results indicated that the soil water movement impacted the transport and concentration of JP-8 in the soil columns. This model can be used to simulate the fate of JP-8 associated with phytoremediation and evapotranspiration.

Remediation of soil and groundwater contaminated by leaking fuel storage tanks may be assisted by plants, although plant effects on abiotic and biotic removal processes remain unclear. The objectives of this study were to investigate abiotic and biotic removal of JP-8, a kerosene-based jet fuel, in soils with plants, and to determine the effects of plant-induced water movement. Loss of JP-8 in a dry-soil, control column was 25% after 5 months, primarily due to volatilization and gas-phase diffusion. By comparison, managed treatments with simulated surface spills averaged 86% mass reduction at 5 months, indicating an important contribution of biodegradation. Overall JP-8 mass reduction was similar in surface and subsurface-irrigated systems, indicating water content, not mode of water application, influences bioremediation in near-surface systems. The JP-8 concentration reductions in soil columns contaminated above a simulated watertable were 36% after 3 months and 50% after 12 months for vegetated columns compared to 26% and 34% in unplanted columns. Downward movement of JP-8 in unplanted columns was double that in planted columns. Near the groundwater table, JP-8 persists longer than near the soil surface. Plants promote upward movement of water and help draw spilled JP-8 to aerobic near-surface soil.

Plant roots interact with organic pollutants and some of these contaminants can be phytotransformed. Root uptake of 1-H-benzotriazole and its derivatives, tolyltriazole, 5-methyl benzotriazole, and 1-hydroxy benzotriazole was studied. At levels below the toxic threshold of about 100 mg/L, triazoles appear to be incorporated into plant tissue. Their concentration in the aqueous phase of the culture decreases with time and they cannot be extracted from the plant material using methanol. Hydroponic studies with sunflowers (Helianthus annuus) were used to investigate the behavior of the solution concentration versus time and to determine kinetic parameters for plant uptake of triazoles. Plants actively take up the triazoles at a rate greater than predicted by transpiration stream-concentration factor and plant-water uptake. Analyses of the data for phytotransformation rate versus concentration were performed to establish the kinetic model for the removal process. Except for 1-hydroxy-benzotriazole, triazole disappearance in plant systems followed the Michaelis-Menten kinetic model (commonly found for enzyme-catalyzed reactions) better than a first order rate model. However, the fit for the first order model was improved when normalizing to the plant fresh weight, which was assumed to be an approximate measure of the changing root surface area. Experiments with other plant species are in progress.

Stabilization and remediation of lead-contaminated soils has received considerable attention recently. Amending Pb-contaminated soils with phosphate as an in situ remediation option has been proposed as an alternative to other remediation options, such as soil removal. Research shows that hydroxyapatite (HA) [Ca(5)(PO(4))(3)OH] can reduce the bioavailability of Pb efficiently and thus is considered as an ideal phosphate source for formation of lead pyromorphite. Environmental models are increasingly being relied upon to help identify the limiting factors in such kind of in situ remediation. In this work, the contaminated aggregates remediation model has been developed and simulated to describe the effects of initial contaminant concentration, diffusion coefficient, and aggregate diameter on the time of remediation which is defined as the time required to reduce the aqueous phase lead concentration to <1 ppb. Results of simulation demonstrate that the aggregate size plays a significant role in remediation. The compartments-in-series model has been used to describe the dynamics of in situ stabilization in a soil bed. Results show that for a shallow bed a single, well-mixed, one compartment model gives approximately the same remediation time as the three compartments-in-series model.

Concentrations measured in alfalfa plant stem segments indicated that plants grown in methyl tert-butyl ether (MTBE)-contaminated soil took up the chemical through their roots. Assuming a cylindrical shape for the plant stem, a mathematical model was developed to describe the transport of MTBE through the stems. Simulation results from uniform and nonuniform initial concentration distributions across the stem radius were compared with steady-state experimental data. With known values of plant stem radius, water usage, water content, and the distance over which the concentration decreased by 50%, the diffusion coefficient of MTBE radial transport across the plant stem was estimated with 95% confidence to be in the range of 8.43-16.2 x 10(-8) cm2/s with a mean of 1.23 x 10(-7) cm2/s. When the diffusion coefficient was calculated based on transient experimental data, the values with 95% confidence interval ranged from 4.14 x 10(-7) to 8.00 x 10(-7) cm2/s with a mean value of 6.07 x 10(-7) cm2/s. The difference between these two results can be reduced by more accurate estimation of the water flow velocity through plant stems. The model is applicable to other species including sunflowers and poplars upon substitution of appropriate parameters.

We report a new principle and technique that allows one to electrodeposit material patterns of arbitrary shape down to the submicrometer scale. We demonstrate that an electrochemical metal deposition reaction can be initiated selectively at surface defects created in a p-type Si(100) substrate by Si (++) focused ion beam bombardment. The key principle is that, for cathodic electrochemical polarization of p-type material in the dark, breakdown of the blocking Schottky barrier at the semiconductor/electrolyte interface occurs at significantly lower voltages at implanted locations than for an unimplanted surface. This difference in the threshold voltages is exploited to achieve selective electrochemical deposition.

Material and energy balances for fermentation processes are developed based on the facts that the heat of reaction per electron transferred to oxygen for a wide variety of organic molecules, the number of available electrons per carbon atom in biomass, and the weight fraction carbon in biomass are relatively constant. Mass-energy balance equations are developed which relate the biomass energetic yield coefficient to sets of variables which may be determined experimentally. Organic substrate consumption, biomass production, oxygen consumption, carbon dioxide production, heat evolution, and nitrogen consumption are considered as measured variables. Application of the balances using direct and indirect methods of yield coefficient estimation is illustrated using experimental results from the literature. Product formation is included in the balance equations and the effect of product formation on biomass yield estimates is examined. Application of mass-energy balances in the optimal operation of continuous single-cell protein production facilities is examined, and the variation of optimal operating conditions with changes in yield are illustrated for methanol as organic substrate.

Vegetation can enhance in situ bioremediation processes in many applications. Microbial transformations occur in soil and water external to plant roots. Organic contaminants also enter vegetation and are transformed within plants. Research progress is reviewed with emphasis on recent experimental results and mathematical models of contaminant fate in systems where vegetation is present. Plant evapotranspiration provides a solar driven pump-and-treat system which moves contaminants to the rhizosphere and helps to contain them on site. Significant savings have been reported at several field sites where vegetation has been utilized.

Activation by opioid receptors of cell proliferation was examined with fibroblast cell lines stably expressing either delta-opioid or mu-opioid receptors. Addition of [D-Ala2, D-Leu5]-enkephalin or [D-Pen2,D-Pen5]-enkephalin to Chinese hamster ovary (CHO) cells transfected with delta-opioid receptor cDNA resulted in an agonist concentration-dependent potentiation of fetal calf serum (FCS)-stimulated cell proliferation. This potentiation by delta-opioid agonists was antagonized by naloxone and was not observed with the kappa-opioid receptor selective agonist U50,488 or the mu-opioid receptor selective agonist [D-Ala2,N-MePhe4, Gly-ol5]-enkephalin. This delta-opioid agonist effect was not observed at FCS concentrations > 0.1% and could be blocked by pretreating cells with pertussis toxin, indicating that Gi/Go were involved in this action. In addition, delta-opioid agonists could potentiate CHO cell proliferation stimulated by those growth factors that are mediated by tyrosine kinase receptors (i.e., insulin, insulin-like growth factor 1, and fibroblast-derived growth factor b). This delta-opioid agonist potentiation of growth apparently was dependent on the level of delta-opioid receptors that were expressed and had cell-line selectivity. Activation of delta-opioid receptors expressed in Rat-1 or NIH3T3 fibroblast did not result in a modulation of the cell growth induced by FCS or by growth factors. Interestingly, in CHO cells transfected with mu-opioid receptor cDNA, activation with agonists did not produce a potentiation of FCS-stimulated proliferation. This lack of mu-opioid receptor effect was not due to the differences among CHO clones. In a CHO cell line transfected with both delta-opioid receptor cDNA and mu-opioid receptor cDNA, activation of delta-but not mu-opioid receptors resulted in a potentiation of growth. These data suggest that delta- and mu-opioid receptors in CHO cells activate similar but divergent second messenger pathways, resulting in the differential regulation of cell growth.

The shear sensitivity of animal and plant cells is a problem often encountered in large-scale cell culture. Such sensitivity varies with different cell lines and the severity of cellular damage may depend on both the magnitude and the duration of the shear stress. In a bioreactor, the shear susceptibility of cells depends on their response to hydrodynamic forces arising from fluid motions of particular scale. Cell damage may be induced by forces in the bulk liquid phase, but fluid motions associated with the gas-liquid interface are especially energetic. The detrimental effects of hydrodynamic forces are abated by the addition of some polymers, such as Pluronic F-68, methylcellulose, or serum; the exact mechanisms of protection are the subject of current research.

Oxygen transfer from gas to liquid under steady-state cocurrent flow conditions was modeled using the dispersion model, and the oxygen transfer coefficients were estimated from available data for a column with Koch motionless mixers. The dispersion in the column was estimated for several different gas and liquid flow rates using steady-state tracer experiments. The estimated oxygen transfer coefficients were compared with those estimated using complete mixing and plug flow models. The results indicate that the dispersion model is the most appropriate model for estimating the mass transfer coefficient from the available data.

Blue-green algae, Spirulina platensis, is cultivated under photoautotrophic growth conditions designed to have nearly uniform growth rate throughout the fermentor by illumination both sides of a rectangular vessel. The results show that growth rate and bioenergetic yield are a function of light intensity. Several kinetic models are considered to express the relationship between growth rate and light intensity.

This work is concerned with statistical methods to estimate yield and maintenance parameters associated with microbial growth. For a given dilution rate, an experimenter typically measures substrate concentration, oxygen utilization rate, the rate of carbon dioxide evolution, and biomass concentration. These correlated response variables each contain information about the maintenance and yield parameters of interest. A maximum likelihood estimator which combines this correlated information for the yield and maintenance parameters is proposed, evaluated, and tested on literature data. Both point and interval estimators are considered.

The effect of vinblastine on the intracellular transport of newly synthesized protein in the mouse exocrine pancreas in vivo was studied by electron microscopic autoradiography after administration of 3H-leucine. Vinblastine (1.1 mumole/mouse; i.v. injection) was in general given 1 h before radioleucine and 2-4 h before fixation of the pancreas by perfusion with glutaraldehyde. Vinblastine causes the disappearance of microtubules, mainly present in controls in the apical portion of the acinar cell. After injection of vinblastine, zymogen granules from clusters located throughout the cell but often associated with Golgi areas. The latter are enlarged mainly due to the accumulation of small vesicles. In addition, Golgi areas are displaced, most often in an apical direction. Electron microscopic autoradiography demonstrated that vinblastine delays the appearance of labeled protein in zymogen granules; even 2 h after injection of radioleucine the majority of silver grains is located over the rough endoplasmic reticulum while very few grains are related to zymogen granules. This finding might be related to the structural changes of the Golgi areas observed. Although intracellular migration of protein is retarded, zymogen granules are formed. However, many of the labeled granules are found in peculiar locations, often distant from the acinar lumen. The present study suggests that vinblastine, possibly due to its effect on microtubules, influences both the formation and the translocation of zymogen granules.

Obtaining accurate estimates of maximum specific growth rate, growth yield, and product yield is important for many fermentation processes. A systematic procedure is presented to select the exponential growth region and estimate the maximum specific growth rate using the covariate adjustment method with all the available measured variables (i.e. biomass, substrate, and product). The procedure is applied to data collected during growth of pure and mixed cultures of Lactobacillus bulgaricus and Streptococcus thermophilus on 3% dry milk under anaerobic conditions. The estimation procedure gives good estimates with relatively narrow confidence intervals even though biomass concentration is measured by an indirect method. The estimated values of maximum specific growth rate range from 0.2805 h(-1) for S. thermophilus (ATCC-19258) to 0.4672 h(-1) for S. thermophilus (Microlife). Growth and product yields are estimated using regression analysis and the data for the exponential growth region. The growth yields are compared to their theoretical maximum values.

Carbon, available electron, and energetic yields are determined from literature data for photoheterotrophic and mixotrophic growth. Maintenance coefficients and energetic yields corrected for maintenance are estimated using covariate adjustment methods for several sets of data. Results are presented and compared for anaerobic photoheterotrophic growth, microaerobic photoheterotrophic growth, aerobic photoheterotrophic growth, and aerobic mixotrophic growth to gain a better understanding of yields for these photosynthetic processes.

Candida lipolytica (strain ATCC 8662) was grown on a simple defined medium with n-hexadecane as the main carbon source under batch fementation conditions. The relative importance of the cells growing in the aqueous phase on the overall kinetics was studied. The effect of interfacial tension, unoccupied interfacial area, and pseudosolubility on the specific growth was also studied. Results are presented and discussed here.

A microwave oven has been used to measure biomass concentration and construct a growth curve for Candida utilis ATCC 1084. Drying curve results show that when a sample was exposed to microwave radiation for 15 min, microwave and air oven dry weight results are within 4 mg of one another when dried at the "cook" power setting (approximately 630 W at full power). For biomass dry weight sample sizes of 147.74 and 14.42 mg, the sample weight was reduced to within 10% of the final air oven dry weight in less than 4 min. At the "defrost" power setting 7 min were required to reduce the sample weight to within 10% of the final air oven dry weight for the large sample. For the small sample, this point was not reached in 15 min. Microwave drying can be used to rapidly estimate microbial biomass concentration.

Methods are presented for examining the consistency of experimental data for microbial growth where light energy is converted to chemical energy through photosynthesis. True growth yield and maintenance parameters are estimated for several sets of available experimental data. Methods of parameter estimation are presented which allow all of the measured variables to be used simultaneously for parameter estimation. The results show that a wide range of values have been found for the true growth yield and maintenance parameters. Values of the true growth yield range from 0.04 to values above those predicted by the Z-scheme model for photosynthesis.

Diffusion of gases through legume nodules is important for nitrogen fixation. A mathematical model is presented for diffusion and enzymatic reaction for legume nodules with a reactive core and an inert shell. The transient model is solved numerically for spherical geometry for acetylene reduction by nitrogenase enzyme. The results are used to estimate the diffusivities of acetylene and ethylene in the nodules by comparing predicted and experimental lag times. The experimental results are also analyzed using an effectiveness factor plot for spherical nodules with inert shells and reactive cores. The results show that the diffusivities are slightly higher than those for acetylene and ethylene in water because of some contribution of gas phase diffusion. Applications to oxygen diffusion through nodule tissue are suggested.

Application of experimental design techniques to Pirt's yield model shows that it is important to collect data at the lowest and highest specific growth rates. In the fed-batch fermentation process, values of specific growth rate can be varied from the maximum value at the start of the process to very low values near the end of the experiment. Candida utilis was cultivated using batch followed by fed-batch culture with glucose as the main source of carbon and energy. Values of substrate concentration, oxygen consumption, carbon dioxide evolution, liquid volume, flow rate cell concentration, and nitrogen concentration, which was an indirect measure of biomass, were measured. Least-squares estimates of the true biomass energetic yield and maintenance coefficient were obtained using a multivariate statistical analysis procedure referred to as the covariate adjustment procedure. Methods of selecting the best estimates using covariate adjustment are illustrated. The results show that useful parameter estimates with relatively short confidence intervals can be obtained using these statistical methods.

Two different strains of Lactobacillus bulgaricus (ATCC-11842 and Microlife) and two strains of Streptococcus thermophilus (ATCC-19258 and Microlife) were grown anaerobically on 3% nonfat dry milk in pure and mixed culture using batch followed by fed batch culture. Samples were collected every 30 min. Concentrations of lactose, galactose, lactic acid, and other products present were measured using high pressure liquid chromatography. A spectrophotometric method from the literature was modified and used to determine microbial biomass concentrations. Relative cell numbers of the two organisms were measured microscopically in mixed culture. The results are presented in tabular form. S. thermophilus (Microlife) showed different growth characteristics compared to the other cultures. This culture utilized most of the galactose that was formed and produced greater amounts of lactic acid and biomass.