Reduction of Environmental Pollutants and Travel Burden Through an Academic Medical Center-based Electronic Consultation Program

Background: We evaluated the impact of electronic consultation (eConsult) in reducing the environmental pollutants associated with health care delivery. Methods: A retrospective analysis of the eConsult data between July 2018 and December 2022 was extracted from the electronic health record (Epic). Travel time and mileage from the patient home to the academic medical center (AMC) were calculated along with fuel expenditure and greenhouses gas savings. Projected savings through the end of the decade were forecast using a random walk model. Results: A total of 15,499 eConsults were submitted to AMC specialist providers from community primary care providers. Completed eConsults (n = 11,590) eliminated the need for a face-to-face visit with a specialist provider, eliminating mileage, fuel, time, and pollutants associated with face to face visits. In-state travel distance saved was 310,858 miles, travel time saved was 5,491 h, with an associated fuel reduction of 13,575 gallons and $56,893 savings. This reduced greenhouse gas emissions by 128 metric tons of carbon dioxide, 0.022 tons of nitrogen oxide, 0.005 tons of methane, and 0.001 tons of nitrous oxide. Out of state travel distance saved was 188,346 miles with 2,842 h reduced travel time, and associated fuel reduction of 8,225 gallons and of $34,118. Reduced greenhouse gas emissions were equivalent to 77 metric tons of carbon dioxide, 0.0132 tons of nitrogen oxide, 0.0033 tons of methane, and 0.0007 tons of nitrous oxide. Conclusion: This study indicates that medical care provided through telehealth modalities reduces the environmental impact of pollutants associated with face to face visits.

ECHO "Bootcamp": An Innovative Training Model to Onboard Providers in the Care of Gender Diverse Patients

Purpose: Extension for Community Health Outcomes (ECHO) is a model of continuing medical education meant to connect academic medical center-based specialists with community providers to increase capacity in managing complex health conditions. The purpose of this study was to evaluate the effectiveness of a shortened "bootcamp" ECHO model in increasing participant competence with topics related to transgender and gender diverse (TGD) health care and the impact of "bootcamp" participation on enrollment in an ongoing ECHO series. Methods: An ongoing monthly ECHO series was instituted on topics of TGD health. After 2 years, the team implemented a four-session "bootcamp" for four consecutive weeks during March 2022 to introduce foundational topics for new participants who had joined or were considering joining the ongoing series. Qualitative and quantitative results were collected from self-reported pre-/post-surveys as well as from in-session quizzes. Results: There were 71 participants in the "bootcamp" including health care providers and support staff. Attendees reported a 10.3% increase (p = 0.02) in self-reported comfort providing care to transgender patients. Pre-/post-knowledge improved in areas of health inequities (50% vs. 74% correct pre/post), surgical requirements (33% vs. 74%), and effects of masculinizing (55% vs. 70%) and feminizing (64% vs. 89%) hormone therapy. Prescribing providers reported a significant change across four areas of practice competency. Among 71 "bootcamp" participants, 15 registered for the ongoing program. Conclusion: Use of a "bootcamp" highlights ways to increase participant comfort and knowledge in providing TGD health care in a shortened timeframe and recruit new participants to an ongoing ECHO curriculum.

Diabetes Technology Use in Remote Pediatric Patients with Type 1 Diabetes Using Clinic-to-Clinic Telemedicine

Background: Clinic-to-clinic telemedicine can increase visit frequency in pediatric patients with type 1 diabetes (T1D) living far from a diabetes specialty clinic, but the impact on adoption of diabetes technology is unclear. Materials and Methods: Pediatric patients with T1D in Colorado and surrounding states who received diabetes care using clinic-to-clinic telemedicine were enrolled. Medical records and surveys were reviewed to ascertain technology use, and data were compared to patients from the main clinic population. Results: Patients (N = 128, baseline mean age 12.4 ± 4.2 years, median T1D duration 3.3 years [IQR 1.4-7.7], mean A1c 8.9% ± 1.8%, 60% male, 75% non-Hispanic white, 77% private insurance) who utilized telemedicine were included. Technology use among telemedicine patients was not associated with gender, T1D duration, insurance, distance from the main clinic or rural designation but was associated with ethnicity and A1c. Compared to the main clinic cohort (N = 3636), continuous glucose monitor (CGM) use and pump/CGM combination use was lower among patients participating in clinic-to-clinic telemedicine (CGM: 29.7% vs. 56.0%, P < 0.001; CGM/pump combination: 27.3% vs. 40.3%, P = 0.004). Technology use was associated with lower A1c regardless of cohort. Conclusions: Compared to patients attending in-person clinic, pediatric T1D patients who use clinic-to-clinic telemedicine due to their distance from the main clinic, have lower CGM and combination CGM/pump use. For both telemedicine and main clinic patients, CGM and CGM/pump combination was associated with lower A1c. Additional research is needed to explore reasons for this discrepancy and find methods to improve CGM use in this population.

Increasing Capacity for Treatment of Opioid Use Disorder in Rural Primary Care Practices

PURPOSE

Evidence supports treatment for opioid use disorder (OUD) with buprenorphine in primary care practices (PCPs). Barriers that slow implementation of this treatment include inadequately trained staff. This study aimed to increase the number of rural PCPs providing OUD treatment with buprenorphine. This evaluation describes the impact of a practice team training on the implementation and delivery of OUD treatment with buprenorphine in PCPs of rural Colorado.

METHODS

Implementing Technology and Medication Assisted Treatment Team Training in Rural Colorado (IT MATTTRs) was a multilevel implementation study that included a practice-focused intervention to improve awareness, adoption, and use of buprenorphine treatment for OUD. Participating PCP teams received the IT MATTTRs Practice Team Training and support. Practices' implementation of treatment components was assessed before and after training. Practice-reported and population-level data from the Prescription Drug Monitoring Program were obtained to describe changes in delivery of treatment after training.

RESULTS

Forty-two practices received team training. Practices reported an average of 4.7 treatment-related components in place at baseline compared with 13.0 at 12-month follow-up (F[2,56] = 31.17, P <.001). The proportion of participating practices providing or referring patients for treatment increased from 18.8% to 74.4%. The increase in number of people with a prescription for buprenorphine was significantly greater in the study region over a 4-year period compared with the rest of the state (Wald χ² = 15.73, P <.001).

CONCLUSIONS

The IT MATTTRs training for PCP teams in OUD treatment with buprenorphine addressed elements beyond clinician waiver training to make implementation feasible and effectively increased implementation and delivery of this treatment in rural Colorado.

Building eConsult (Electronic Consults) Capability at an Academic Medical Center to Improve Efficiencies in Delivering Specialty Care

As the COVID-19 health crisis continues to reshape healthcare, systems across the country face increasing pressure to adapt their models of care to expand access to care, while also improving efficiency and quality in the face of limited resources. Consequently, many have shown a growing interest and receptivity to the expansion of telehealth models to help meet these demands. Electronic consultations (eConsults) are a telehealth modality that allow for a non-face-to-face asynchronous consultation between a primary care provider (PCP) and a specialist aimed at facilitating specialist input without the need for a patient visit. The aim of this case study is to describe eConsults, how they differ from traditional in person models of care and other models of telemedicine and to review the evidence related to the effectiveness of eConsults by PCPs and clinicians from multiple specialties at the University of Colorado School of Medicine. We have worked to develop an infrastructure, delivery system integration, and care model adaptations that aim to improve delivery system performance by ensuring proper care in appropriate settings and lowering costs through reduced utilization. Lastly, we have increased care coordination, improved collaboration and better care transitions through strengthening of relationships between community-based PCPs and academic medical center-based specialists. This work has resulted in cost savings to patients and positive provider satisfaction.

Teaching Helping Babies Breathe via Telehealth: A New Application in Rural Guatemala

Background

Helping Babies Breathe (HBB) is a neonatal resuscitation curriculum that teaches life-saving interventions utilized in the first minutes after birth, reducing morbidity and mortality. Traditionally, it requires in-person facilitators for didactic and hands-on training.

Objectives

The aim of this study was to offer HBB to nurses and nursing students in Guatemala, with the lead facilitator presenting concepts via telehealth and in-person facilitators providing hands-on demonstration.

Methods

Learners completed pre- and post-tests that included the standard HBB knowledge check, as well as an assessment of the course teaching model. Learners also completed the standard Objective Structured Clinical Evaluations (OSCEs).

Results

Eighteen learners were included in the analysis. All but one learner (94%) passed the course, and the average percent improvement from the pre- to post-test was 12%. All learners achieved passing scores on the OSCEs. Learners responded positively to questions regarding the technology, connection with the instructor, and ability to ask questions. Ninety-four percent of the learners agreed with the statement "this lecture was as good via telehealth as in person." A cost analysis demonstrated approximately USD 3,979.00 in savings using telehealth compared to a standard in-person course.

Conclusions

The telehealth model was successful in delivering course material to the learners and was well received. This model represents a cost-effective way to improve access to HBB. This study may not be generalizable to other populations, and the ability to use telehealth requires reliable internet connectivity, which may not be available in all settings. Further study and expansion of this pilot are needed to assess success in other settings.

Implementing a Home-Based Telehealth Group Adherence Intervention with Adolescent Transplant Recipients

Introduction: To improve access to care and engage adolescent transplant recipients for adherence-promoting interventions, innovative solutions utilizing technology are needed. Materials and Methods: This study describes the implementation of a five-session group intervention targeting medication adherence in adolescent transplant recipients through home-based telemedicine. Results: Seven videoconferencing groups were conducted with a total of 33 participants living a median of 57 miles away from their transplant medical center. The median coefficient of variation (CV) of tacrolimus (immunosuppression medication) decreased from 32.2% to 23.5% from the pregroup to postgroup phase. Analyses indicated that the group was acceptable and engaging for participants, as highlighted by one participant reporting, "I liked how me and the group members came together… it felt like a little family." Overall satisfaction with the group and with the technology was endorsed by 86%. The group intervention was generally feasible; however, there were technological difficulties reported by participants and the facilitator, particularly given the diversity of the home-based connections and equipment. Other adaptations helped improve recruitment, attendance, and participation. Discussion: Implementing a telehealth group can pose unique challenges, especially with a group of adolescent participants. Although nonsignificant, we observed a decrease in the median CV of tacrolimus, indicating that medication adherence generally improved after group intervention. Our experience facilitating these groups provides insights into strategies to optimize feasibility and the participant experience. Distance of participants from the hospital is an important consideration and provides a strong rationale for the need for telemedicine-enabled approaches. We explore and discuss the challenges to implementing a home-based group, suggest practical strategies and developmentally sensitive adjustments when working with adolescents, and propose strategies to prepare clinicians for obstacles that may present when implementing a telehealth group with youth.

The Use of Telepsychiatry to Provide Cost-Efficient Care During Pediatric Mental Health Emergencies

OBJECTIVE

This study evaluated a videoconference-based psychiatric emergency consultation program (telepsychiatry) at geographically dispersed emergency department (ED) sites that are part of the network of care of an academic children's hospital system. The study compared program outcomes with those of usual care involving ambulance transport to the hospital for in-person psychiatric emergency consultation prior to disposition to inpatient care or discharge home.

METHODS

This study compared process outcomes in a cross-sectional, pre-post design at five network-of-care sites before and after systemwide implementation of telepsychiatry consultation in 2015. Clinical records on 494 pediatric psychiatric emergencies included ED length of stay, disposition/discharge, and hospital system charges. Satisfaction surveys regarding telepsychiatry consultations were completed by providers and parents or guardians.

RESULTS

Compared with children who received usual care, children who received telepsychiatry consultations had significantly shorter median ED lengths of stay (5.5 hours and 8.3 hours, respectively, p<.001) and lower total patient charges ($3,493 and $8,611, p<.001). Providers and patient caregivers reported high satisfaction with overall acceptability, effectiveness, and efficiency of telepsychiatry. No safety concerns were indicated based on readmissions within 72 hours in either treatment condition.

CONCLUSIONS

Measured by charges and time, telepsychiatry consultations for pediatric psychiatric emergencies were cost-efficient from a hospital system perspective compared with usual care consisting of ambulance transport for in-person consultation at a children's hospital main campus. Telepsychiatry also improved clinical and operational efficiency and patient and family experience, and it showed promise for increasing access to other specialized health care needs.

Association of parental health literacy with oral health of Navajo Nation preschoolers

Health literacy is 'the capacity to obtain, process and understand basic health information and services needed to make appropriate health decisions'. Although numerous studies show a link between health literacy and clinical outcomes, little research has examined the association of health literacy with oral health. No large-scale studies have assessed these relationships among American Indians, a population at risk for limited health literacy and oral health problems. This analysis was conducted as part of a clinical trial aimed at reducing dental decay among preschoolers in the Navajo Nation Head Start program. Using baseline data for 1016 parent-child dyads, we examined the association of parental health literacy with parents' oral health knowledge, attitudes, and behavior, as well as indicators of parental and pediatric oral health. More limited health literacy was associated with lower levels of oral health knowledge, more negative oral health attitudes, and lower levels of adherence to recommended oral health behavior. Parents with more limited health literacy also had significantly worse oral health status (OHS) and reported their children to have significantly worse oral health-related quality of life. These results highlight the importance of oral health promotion interventions that are sensitive to the needs of participants with limited health literacy.

Use of Telemedicine to Improve Adherence to American Diabetes Association Standards in Pediatric Type 1 Diabetes

BACKGROUND

The American Diabetes Association (ADA) recommends that children with type 1 diabetes (T1D) see a multidisciplinary team and have hemoglobin A1c (A1C) levels measured every 3 months. Patients in rural areas may not follow guidelines because of limited specialty care access. We hypothesized that videoconferencing would result in equivalent A1C compared with in-person visits and increased compliance with ADA recommendations.

MATERIALS AND METHODS

The Barbara Davis Center (BDC) (Aurora, CO) telemedicine program provides diabetes care to pediatric patients in Casper and Cheyenne, WY, via remote consultation with annual in-person visits. Over 27 months, 70 patients were consented, and 54 patients completed 1 year in the study.

RESULTS

Patients were 70% male, with a mean age of 12.1 ± 4.1 years and T1D duration of 5.4 ± 4.1 years. There was no significant change between baseline and 1-year A1C levels for patients with data at both time points. Patients saw diabetes specialists an average of 2.0 ± 1.3 times per year in the year prior to starting telemedicine and 2.9 ± 1.3 times (P < 0.0001) in the year after starting telemedicine. Patients and families missed significantly less school and work time to attend appointments.

CONCLUSIONS

Our study suggests telemedicine is equivalent to in-person visits to maintain A1C, whereas families increase the number of visits in line with ADA recommendations. Patients and families miss less school and work. Decreased financial burden and increased access may improve overall diabetes care and compliance for rural patients. Further study is needed to detect long-term differences in complications screenings and the financial impact of telemedicine on pediatric diabetes care.

Teen dating violence and substance use following a natural disaster: does evacuation status matter?

OBJECTIVES

In September 2008, the Texas coast was directly hit by Hurricane Ike. Galveston Island was flooded by 4.25 m of storm surge, affecting most of the island's housing and infrastructure. The purpose of this study is to examine whether youth who did not evacuate (11 percent), and subsequently were exposed to Hurricane Ike, exhibit higher rates of substance use and physical and sexual teen dating violence (TDV; both perpetration and victimization) when compared with adolescents who did evacuate.

SETTING

Public high school in southeast Texas that was in the direct path of Hurricane Ike.

PARTICIPANTS

An anonymous survey was conducted in March 2009 to 1,048 high school students who returned to the Galveston Island post-storm (41 percent Hispanic, 23 percent African American, and 27 percent White).

MAIN OUTCOME MEASURES

Teen dating violence and substance use.

RESULTS

Mantel-Haenszel odds ratios, adjusting for age and ethnicity, were computed. When compared with boys who evacuated, nonevacuating boys were more likely to perpetrate physical dating violence and sexual assault and to be a victim of sexual assault. Nonevacuating boys and girls were more likely to report recent use of excessive alcohol, marijuana, and cocaine than those who did evacuate.

CONCLUSIONS

School personnel, medical personnel, and mental health service providers should consider screening for evacuation status in seeking to identify those adolescents who most need services after a natural disaster. In addition to addressing internalized emotions and psychological symptoms associated with experiencing trauma, intervention programs should focus on reducing externalized behavior such as substance use and TDV.

Reversion of flowering in Glycine Max (Fabaceae)

Photoperiodic changes, if occurring before a commitment to flowering is established, can alter the morphological pattern of plant development. In this study, Glycine max (L.) Merrill cv. Ransom plants were initially grown under an inductive short-day (SD) photoperiod to promote flower evocation and then transferred to a long-day (LD) photoperiod to delay flower development by reestablishing vegetative growth (SD-LD plants). Some plants were transferred back to SD after 4-LD exposures to repromote flowering (SD-LD-SD plants). Alterations in organ initiation patterns, from floral to vegetative and back to floral, are characteristic of a reversion phenomenon. Morphological features that occurred at the shoot apical meristem in SD, LD, SD-LD, and SD-LD-SD plants were observed using scanning electron microscopy (SEM). Reverted plants initiated floral bracts and resumed initiation of trifoliolate leaves in the two-fifths floral phyllotaxy prior to terminal inflorescence development. When these plants matured, leaf-bract intermediates were positioned on the main stem instead of trifoliolate leaves. Plants transferred back to a SD photoperiod flowered earlier than those left in LD conditions. Results indicated that in plants transferred between SDs and LDs, photoperiod can influence organ initiation in florally evoked, but not committed, G. max plants.

CD4-independent infection by HIV-2 is mediated by fusin/CXCR4

Several members of the chemokine receptor family have been shown to function in association with CD4 to permit HIV-1 entry and infection. However, the mechanism by which these molecules serve as CD4-associated cofactors is unclear. In the present report, we show that one member of this family, termed Fusin/ CXCR4, is able to function as an alternative receptor for some isolates of HIV-2 in the absence of CD4. This conclusion is supported by the finding that (1) CD4-independent infection by these viruses is inhibited by an anti-Fusin monoclonal antibody, (2) Fusin expression renders human and nonhuman CD4-negative cell lines sensitive to HIV-2-induced syncytium induction and/or infection, and (3) Fusin is selectively down-regulated from the cell surface following HIV-2 infection. The finding that one chemokine receptor can function as a primary viral receptor strongly suggests that the HIV envelope glycoprotein contains a binding site for these proteins and that differences in the affinity and/or the availability of this site can extend the host range of these viruses to include a number of CD4-negative cell types.

Chaos in thermal pulse combustion

An experimental thermal pulse combustor and a differential equation model of this device are shown to exhibit chaotic behavior under certain conditions. Chaos arises in the model by means of a progression of period-doubling bifurcations that occur when operating parameters such as combustor wall temperature or air/fuel flow are adjusted to push the system toward flameout. Bifurcation sequences have not yet been reproduced experimentally, but similarities are demonstrated between the dynamic features of pressure fluctuations in the model and experiment. Correlation dimension, Kolmogorov entropy, and projections of reconstructed attractors using chaotic time series analysis are demonstrated to be useful in classifying dynamical behavior of the experimental combustor and for comparison of test data to the model results. Ways to improve the model are suggested. (c) 1995 American Institute of Physics.

Involvement of p21ras distinguishes positive and negative selection in thymocytes

Small molecular weight GTP binding proteins of the ras family have been implicated in signal transduction from the T cell antigen receptor (TCR). To test the importance of p21ras in the control of thymocyte development, we generated mice expressing a dominant-negative p21ras protein (H-rasN17) in T lineage cells under the control of the lck proximal promoter. Proliferation of thymocytes from lck-H-rasN17 mice in response to TCR stimulation was nearly completely blocked, confirming the importance of p21ras in mediating TCR-derived signals in mature CD4+8- or CD8+4- thymocytes. In contrast, some TCR-derived signals proceeded unimpaired in the CD4+8+ thymocytes of mice expressing dominant-negative p21ras. Analysis of thymocyte development in mice made doubly transgenic for the H-Y-specific TCR and lck-H-rasN17 demonstrated that antigen-specific negative selection occurs normally in the presence of p21H-rasN17. Superantigen-induced negative selection in vivo also proceeded unhindered in H-rasN17 thymocytes. In contrast, positive selection of thymocytes in the H-Y mice was severely compromised by the presence of p21H-rasN17. These observations demonstrate that positive and negative selection, two conceptually antithetical consequences of TCR stimulation, are biochemically distinguishable.

Promontory electrical stimulation in postoperative acoustic tumor patients

Complete deafness can follow acoustic tumor surgery and results from labyrinthine injury, auditory nerve trauma, and/or vascular compromise. A central auditory prosthesis is one potential rehabilitative strategy in such patients. Anatomical studies suggest that some spiral ganglion cells may survive after vascular occlusion, and we have demonstrated responses to electrical stimulation in patients after labyrinthectomy. It was thus hypothesized that patients deafened after a hearing conservation attempt, but maintaining an intact auditory nerve, could utilize an intracochlear implant. To investigate this possibility, promontory electrical stimulation was performed on three patients who had tumors less than 2 cm and who had serviceable preoperative hearing, but no responses postoperatively. Behavioral responses and electrically evoked auditory brainstem and middle latency responses were obtained from two patients, one of whom was 6 years postsurgery. These data indicate that a cochlear implant may be possible after acoustic tumor surgery.

Some social correlates with the dental health of young children

A socio-dental investigation was carried out among 405 five-year-old school children living in a predominantly rural area of West Wales. Information was gathered from a clinical examination of the children and a questionnaire to their parents. The replies to the questionnaires were then cross-tabulated with the clinical findings. The results indicated that lower dmft values were positively associated with household ownership of a telephone and a car and a higher educational attainment by mothers. Mothers with a high level of anxiety about a dental visit and an expectation of eventual edentulousness tended to be the parents of the children with the highest level of untreated carious teeth. The importance of a family pattern of service use is also demonstrated.

Lead intake and blood lead in two-year-old U.K. urban children

A comprehensive study of a group of 2-year-old urban children (n = 97), designed to provide quantitative information simultaneously for lead intakes via all identified pathways, has been carried out in Birmingham (U.K.). Results showed that for children whose blood levels and exposure to environmental lead were within the normal range for the U.K., blood lead concentration was significantly related to a combination of house dust lead loading and an overall rate of touching objects, to water lead concentration and to the parents' smoking habits. On the basis of assumptions used by the Royal Commission on Environmental Pollution (RCEP), the estimated average total uptake of lead was 36 micrograms day-1; of this, 97% was from ingestion from dust, food and water and only 3% from inhalation.

Assessment of an apparent relationship between availability of soluble carbohydrates and reduced nitrogen during floral initiation in tobacco

Daily relative accumulation rate of soluble carbohydrates (RARS) and reduced nitrogen (RARN) in the shoot, as estimates of source strength, were compared with daily relative growth rates (RGR) of the shoot, as an estimate of sink demand, during floral transformation in apical meristems of tobacco (Nicotiana tabacum 'NC 2326') grown at day/night temperatures of 18/14, 22/18, 26/22, 30/26, and 34/30 C. Source strength was assumed to exceed sink demand for either carbohydrates or nitrogen when the ratio of RARS/RGR or RARN/RGR was greater than unity, and sink demand was assumed to exceed source strength when the ratio was less than unity. Time of floral initiation, which was delayed up to 21 days with increases in temperature over the experimental range, was associated with intervals in which source strength of either carbohydrate or nitrogen exceeded sink demand, while sink demand for the other exceeded source strength. Floral initiation was not observed during intervals in which source strengths of both carbohydrates and nitrogen were greater than or less than sink demand. These results indicate that floral initiation is responsive to an imbalance in the relative availabilities of carbohydrate and nitrogen.

Safety margins for lead in the general population

The results of monitoring blood lead concentrations, the accepted biological indicator for lead in man, are examined against the three trigger values put forward in the UK, first as justifying environmental investigation (25 μg 100 ml(-1)), second as justifying health checks (35 μg 100 ml(-1)) and third as likely to give rise to obvious symptoms in a few individuals (50 μg 100 ml(-1)). Arguments for using the proportion or the number of individuals above a trigger value rather than the ratio of the mean blood lead concentration to the trigger value, the conventional safety margin, are presented. The numbers of individuals or proportions in the total population who are likely to be above the trigger values have been estimated and shown to be relatively small for all three. Factors likely to affect blood lead concentrations are examined against the possible effects of the changes, current and proposed, in the controls imposed on lead usage and on pathways. The qualitative changes expected are considered by groups-eg. smokers and drinkers, by regions, eg., those with lead-free drinking water as against those still with lead in their supplies, and for the general population eg. from the elimination of the soldered can for food and the reduction, and eventual elimination, of lead in petrol.Because the relationship between intake and blood concentration is non-linear in the UK, those with the highest existing blood lead concentrations in the general population must be expected to show the smallest relative reductions in blood lead for any small reduction in exposure. The analysis also concludes that those at highest risk will have to depend on their being identified individually and action taken on them and their immediate specific environment.

Intercellular localization of nitrate reductase in roots

Experiments were conducted with segments of corn roots to investigate whether nitrate reductase (NR) is compartmentalized in particular groups of cells that collectively form the root symplastic pathway. A microsurgical technique was used to separate cells of the epidermis, of the cortex, and of the stele. The presence of NR was determined using in vitro and enzyme-linked immunosorbent assays. In roots exposed to 0.2 millimolar NO(3) (-) for 20 hours, NR was detected almost exclusively in epidermal cells, even though substantial amounts of NO(3) (-) likely were being transported through cortical and steler cells during transit to the vascular system. Although NR was present in all cell groups of roots exposed to 20.0 millimolar NO(3) (-), the majority of the NR still was contained in epidermal cells. The results are consistent with previous observations indicating that limited reduction of endogenous NO(3) (-) occurs during uptake and reduction of exogenous NO(3) (-). Several mechanisms are advanced to account for the restricted capacity of cortical and stelar cells to induce NR and reduce NO(3) (-). It is postulated that (a) the biochemical system involved in the induction of NR in the cortex and stele is relatively insensitive to the presence of NO(3) (-), (b) the receptor for the NR induction response and the NR protein are associated with cell plasmalemmae and little NO(3) (-) is taken up by cells of the cortex and stele, and/or (c) NO(3) (-) is compartmentalized during transport through the symplasm, which limits exposure for induction of NR and NO(3) (-) reduction.

Internode and petiole elongation of soybean in response to photoperiod and end-of-day light quality

Elongation of main stem internodes and petioles of soybeans, Glycine max 'Ransom,' was examined in response to various photoperiod/temperature combinations and to end-of-day (EOD) light quality. Photoperiod treatments consisted of 10, 14, and 16 h in combination with day/night temperatures of 18/14, 22/18, 26/22, 30/26, and 34/30 C. The EOD treatments consisted of exposing plants to illumination from either incandescent (high far-red component, FR) or fluorescent (high red component, R) lamps during the final 0.5 h of a 10-h photoperiod. Internode elongation was not significantly promoted by the photoperiod treatments, and, in fact, under the two highest temperature regimes, internode elongation was suppressed under the longer photoperiods. Petiole elongation, however, was enhanced under the longer photoperiods at all temperatures. In the EOD light study, internode and petiole elongation was significantly greater on plants exposed to 0.5 h EOD from incandescent lamps than from fluorescent. Under the incandescent EOD treatment, plants increased dry matter production by 41% and exhibited greater partitioning of assimilates in stem and root portions than under fluorescent EOD.

Photoperiod regulation of floral initiation for soybean plants at different ages

Soybean plants [Glycine max (L.) Merr.] of the determinate cultivar Ransom growing in controlled environments under 16-h photoperiods were exposed to 10, 12, 14, 15, and 16-h photoperiods upon expansion of either the two primaries or fifth trifoliolate leaf (V1 and V6 developmental stages, respectively) to determine the influence of plant size on sensitivity to photoperiod. Plants were sampled at 2 to 3-day intervals over a 21-day treatment period and examined microscopically for evidence of floral development. Time of floral initiation for plants exposed to photoperiod treatments at either V1 or V6 stage varied only by a few days among photoperiods, but the subsequent differentiation of floral primordia was much more rapid at shorter than at longer photoperiods. These results confirm previous observations for plants transferred upon expansion of the first trifoliolate leaf (V2 stage) and indicate that sensitivity of floral responsiveness to photoperiod changed little with plant size.

Response of Agronomic and Forest Species to Elevated Atmospheric Carbon Dioxide

The effects of atmospheric carbon dioxide on corn, soybeans, loblolly pine, and sweetgum were studied in the field during a growing season. The plants were exposed to a range of concentrations of carbon dioxide day and night in open-topped, flow-through chambers. At a mean daytime carbon dioxide concentration of 910 parts per million, increases in total biomass ranged from 157 to 186 percent of the control values. Seed yield and wood volume increased and there were changes in plant anatomy and form. Net photosynthesis increased with increasing carbon dioxide concentration in soybeans and sweetgum, but was unaffected in corn. Water use efficiency also increased in corn, soybeans, and sweetgum.

Integrated monitoring - Principles and practice

The concept of integrated monitoring is examined and defined. The different types and applications of monitoring in the United Kingdom are considered against the information they can provide. Two examples of integrated monitoring of health hazards in the UK are described. The relevance of the principles and the practice to the assessment of regional and global environmental problems is discussed and suggestions made for their review.

Phytochrome Regulation of Flowering in the Long-Day Plant, Hyoscyamus niger

A daylength extension with incandescent light is more effective in promoting flowering of long-day plants like Hyoscyamus niger than fluorescent light. A low phytochrome photoequilibrium (Pfr/P(tot)), attained by a far-red irradiation at the close of long days under fluorescent light, also promotes flowering. Moreover, if flower initiation processes are initiated by several long days, a low phytochrome photoequilibrium at the end of short, postinduction photoperiods also enhances flowering. The initiation phase of flowering requires Pfr to be present whereas the development phase proceeds more rapidly in the absence of Pfr. Spectral dependence studies, therefore, could be misinterpreted if the initiation and development stages are combined into a single audit of flowering.

Sickle cell trait counseling-evaluation of counselors and counselees

In this study, information about both counselee and counselor performance was obtained from taped recordings of 193 structured counseling sessions with persons diagnosed as having sickle cell trait. The data provide evidence that: (1) lay persons can understand essential sickle cell information; (2) trained lay persons using a structured format can transmit successfully sickle cell information; (3) only education and age, among counselee characteristics studies, were related to successful learning; (4) the evaluation of information transfer in counseling programs cannot be limited to counselees' comprehension but must also consider other variables such as counselor performance and curriculum content; (5) a reduction in negative feelings associated with a diagnosis of sickle cell trait is an immediate effect of counseling; and (6) audio-taping of counseling sessions is client acceptable and useful for evaluation, quality control, and counselor training.