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To determine the unmet need for care and barriers for consulting sexually transmitted infection (STI) services at six primary healthcare (PHC) facilities in rural South Africa.Cross-sectional study using three community-based strategies to mobilise adult individuals with STI-associated symptoms to access care. Participants were mobilised through clinic posters and referral by community healthcare workers (CHWs) and traditional leaders after training. Men with male urethritis syndrome and women with vaginal discharge syndrome were mobilised to visit participating PHC facilities on two designated days when an expert team visited the facility. Questionnaires were completed and HIV rapid tests offered. The minimal unmet need for care of individuals with STI-associated symptoms was calculated by dividing the number of cases over the adult catchment population of each PHC facility.We successfully mobilised 177 symptomatic individuals: 134 (76%) women and 43 (24%) men. The estimated minimal unmet need for STI care was 1:364 (95% CI 1:350-1:380) individuals in this region; the rate was higher in village than township facilities, and among women. Mobilisation through clinic posters (57%) and by CHWs (23%) was most successful. Three-quarters of individuals (132/177) reported symptoms that had been present for30 days; 49% (87/177) had symptoms6 months. In addition, we identified 14 individuals with untreated HIV infection amounting to a 7% HIV testing yield. Lack of awareness of symptoms (34%), and disappointment in care due to persistent (23%) or recurrent (15%) symptoms after previous treatment, or disappointment with health services in general during previous visit(s) for any reason (10%) was the most common reasons for not consulting health care.We demonstrate a high unmet need for care of individuals with STI-associated symptoms in rural South Africa that requires urgent attention. A multidisciplinary approach that creates service demand through community awareness and information provision by healthcare workers combined with strengthening the quality of STI services is required to improve reproductive health and prevent complications of untreated STIs in this population.Déterminer les besoins non satisfaits en matière de soins et les obstacles à la consultation des services pour IST dans six établissements de soins de santé primaires (SSP) en milieu rural en Afrique du Sud. MÉTHODES: Etude transversale utilisant trois stratégies communautaires pour mobiliser les individus adultes présentant des symptômes associés aux IST afin qu'ils puissent accéder aux soins. Les participants ont été mobilisés à travers des affiches dans les cliniques et sur recommandation des agents de santé communautaires (ASC) et des chefs traditionnels après une formation. Les hommes atteints du syndrome d'urétrite masculin et les femmes atteintes du syndrome de pertes vaginales ont été mobilisés à visiter les établissements de SSP participants, au cours de deux jours choisis lorsqu'une équipe d'experts était présente dans l’établissement. Des questionnaires ont été remplis et des tests de dépistage rapides du VIH ont été proposés. Le besoin minimal non satisfait de soins pour les personnes présentant des symptômes associés aux IST a été calculé en divisant le nombre de cas par la population adulte de la zone de chaque établissement de SSP. RÉSULTATS: Nous avons réussi à mobiliser 177 personnes symptomatiques: 134 (76%) femmes et 43 (24%) hommes. Le besoin minimal non satisfait en matière de soins IST était de 1:364 (IC95%: 1:350 - 1:380) individus dans cette région; le taux était plus élevé dans les villages que dans les installations des bidonvilles et chez les femmes. La mobilisation par le biais d'affiches de cliniques (57%) et par les ASC (23%) a eu le plus de succès. Les trois quarts des personnes (132/177) ont signalé des symptômes présents depuis30 jours; 49% (87/177) présentaient des symptômes6 mois. En outre, nous avons identifié 14 personnes présentant une infection par le VIH, non traitée, ce qui représente un rendement de dépistage du VIH de 7%. Le manque de prise de conscience des symptômes (34%) et la déception avec les soins en raison de symptômes persistants (23%) ou récurrents (15%) après un traitement précédent, ou la déception avec les services de santé en général lors de visites précédentes pour une raison quelconque (10 %) étaient les raisons les plus courantes de ne pas consulter les soins de santé.Dans les zones rurales d'Afrique du Sud, nous démontrons un besoin élevé de soins non satisfaits pour les personnes présentant des symptômes associés aux IST et nécessitant une attention urgente. Une approche multidisciplinaire qui crée une demande de services par le biais de la sensibilisation de la communauté et de la fourniture d'informations par les agents de santé, associée au renforcement de la qualité des services IST, est nécessaire pour améliorer la santé reproductive et prévenir les complications des IST non traitées dans cette population.

Introduction Facility‐based HIV testing services (HTS) have been less acceptable and accessible by adolescents, men and key populations in South Africa. Community‐based HIV counselling and testing (CBCT) modalities, including mobile unit and home‐based testing, have been proposed to decrease barriers to HIV testing uptake. CBCT modalities and approaches may be differentially acceptable to men and women based on age. Implementation of multimodal CBCT services may improve HIV testing rates among adolescents and men, and support the roll‐out of prevention services. Methods A cross‐sectional analysis was conducted using aggregate, routine programmatic data collected from 1 October 2015 through 31 March 2017 from a multimodal, at‐scale CBCT programme implemented in 12 high‐burden districts throughout South Africa. Data collection tools were aligned to reporting standards for the National Department of Health and donor requirements. HIV testing rates (i.e. number of tests performed per 100,000 population using South African census data) and testing proportions by modality were stratified by sex, age groups and heath districts. Descriptive statistics were performed using STATA 13.0. Results Overall, 944,487 tests were performed during the 1.5‐year testing period reported. More tests were conducted among females than males (53.6% vs. 46.4%). Overall, 8206 tests per 100,000 population (95% CI: 8190.2 to 8221.9) were performed; female‐to‐male (F:M) testing ratio was 1.11. Testing rates were highest among young women age 20 to 24 years (16,328.4; 95% CI: 16,237.9 to 16,419.1) and adolescent girls aged 15 to 19 years (12,817.0; 95% CI: 12,727.9 to 12,906.6). Home‐based testing accounted for 61.3% of HIV tests, followed by near‐home mobile unit testing (30.2%) and workplace mobile unit testing (4.7%). More women received HTS via home‐based testing (F:M ratio = 1.29), whereas more men accessed work‐place mobile testing (M:F ratio = 1.35). No sex differential was observed among those accessing near‐home mobile testing (F:M ratio = 0.98). Conclusions Concurrent implementation of multiple, targeted CBCT modalities can reduce sex disparities in HIV testing in South Africa. Given the acceptability and accessibility of these CBCT services to adolescent girls and young women, evident from their high testing rates, leveraging community‐based services delivery platforms to increase access to HIV prevention services, including pre‐exposure prophylaxis (PrEP), should be considered.

In this article, a black-box higher order fast multipole method for solving boundary integral equations on parametric surfaces in three spatial dimensions is proposed. Such piecewise smooth surfaces are the topic of recent studies in isogeometric analysis. Due to the exact surface representation, the rate of convergence of higher order methods is not limited by approximation errors of the surface. An element-wise clustering strategy yields a balanced cluster tree and an efficient numerical integration scheme for the underlying Galerkin method. By performing the interpolation for the fast multipole method directly on the reference domain, the cost complexity in the polynomial degree is reduced by one order. This gain is independent of the application of either (mathcal{H})- or (mathcal{H}^2)-matrices. In fact, several simplifications in the construction of (mathcal{H}^2)-matrices are pointed out, which are a by-product of the surface representation. Extensive numerical examples are provided in order to quantify and qualify the proposed method. In this article, a black-box higher order fast multipole method for solving boundary integral equations on parametric surfaces in three spatial dimensions is proposed. Such piecewise smooth surfaces are the topic of recent studies in isogeometric analysis. Due to the exact surface representation, the rate of convergence of higher order methods is not limited by approximation errors of the surface. An element-wise clustering strategy yields a balanced cluster tree and an efficient numerical integration scheme for the underlying Galerkin method. By performing the interpolation for the fast multipole method directly on the reference domain, the cost complexity in the polynomial degree is reducedby one order. This gain is independent of the application of either H - or H 2- matrices. In fact, several simplificationsin the construction of H 2 -matrices are pointed out, which are a by-product of the surface representation. Extensive numerical examples are provided in order to quantify and qualify the proposed method.

Objectives To assess the performance of an innovative method of transporting sputum to centralised facilities for molecular detection of Mycobacterium tuberculosis: using a swab to inoculate sputum in a transport medium, PrimeStore® Molecular Transport Medium (PS-MTM). Methods Two sputum specimens were obtained from suspected patients with tuberculosis (TB) at rural healthcare facilities in South Africa. A swab was taken from each specimen and placed into PS-MTM, prior to it being processed by either liquid culture or Xpert MTB/RIF assay (Xpert). Results A total of 141 patients (including 47 with laboratory-confirmed TB) were included in this analysis. M. tuberculosis was detected at 29% by culture and 29% by Xpert, whereas 31% tested positive by IS6110 real-time PCR of PS-MTM from the culture and 36% from the Xpert-paired specimen. Concordance between the method under evaluation with culture was 82% (McNemar, P = 0.55) and 84% (McNemar, P = 0.05) for Xpert. Stratified by culture result, the detection rate by IS6110 real-time PCR of PS-MTM was similar to Xpert for patients with positive culture (P = 0.32), but significantly higher if culture was negative (P = 0.008). Conclusions These results suggest that swab collection of sputum into PS-MTM for transport is a promising method for diagnosis of TB in rural healthcare settings, thereby potentially improving the options available for molecular diagnosis of TB in countries incapable of applying decentralised high-tech molecular testing.

Introduction The objective of this study was to assess the association between health facility characteristics and other individual/household factors with a woman's likelihood of skilled birth attendance in north-central Afghanistan. Methods Data from a 2010 household survey of 6879 households in 9 provinces of Afghanistan were linked to routine facility data. Hierarchical logistic regression models were used to assess determinants of skilled birth attendance. Results Women who reported having at least one antenatal visit with a skilled provider were 5.6 times more likely to give birth with a skilled attendant than those who did not. The odds of skilled birth attendance were 84% higher for literate women than those without literacy skills and 79% higher among women in the upper 2 wealth quintiles than women in the poorest quintile. This study did not show any direct linkages between facility characteristics and skilled birth attendance but provided insights into why studies assuming that women seek care at the nearest primary care facility may lead to misinterpretation of care-seeking patterns. Findings reveal a 36 percentage point gap between women who receive skilled antenatal care and those who received skilled birth care. Nearly 60% of women with a skilled attendant at their most recent birth bypassed the nearest primary care facility to give birth at a more distant primary care facility, hospital, or private clinic. Distance and transport barriers were reported as the most common reasons for home birth. Discussion Assumptions that women who give birth with a skilled attendant do so at the closest health facility may mask the importance of supply-side determinants of skilled birth attendance. More research based on actual utilization patterns, not assumed catchment areas, is needed to truly understand the factors influencing care-seeking decisions in both emergency and nonemergency situations and to adapt strategies to reduce preventable mortality and morbidity in Afghanistan.

We investigate the electro-optic properties of two oppositely ramped asymmetric quantum well structures in the AlInGaAs material system. The grading of the bandgap in the quantum wells has been achieved by changing the ratio of Al to Ga in the quaternary alloy during the epitaxial growth. The surface normal photo-response and the Fabry–Perot fringe shift in straight waveguides are compared for both structures as a function of applied voltage at 1550 nm for TE-polarized light. The measurements show a change in the refractive index due to a red shift of the excitonic resonances due to the quantum-confined Stark effect. The 10 quantum well structure with a ramp up of the bandgap in the growth direction leads to the figure of merit of the voltage for a π phase shift, Vπ by length, L, Vπ × L, of 6 as compared to 7 V · mm in the structure with a ramp in opposite direction. Further investigations show that the reduction in Vπ is due to increased absorption at high reverse bias which induces a non-linear phase change.

Contains fulltext : 153318.pdf (Publisher’s version ) (Open Access) Insight into the maintenance of naive T cells is essential to understand defective immune responses in the context of aging and other immune compromised states. In humans, naive CD4+ T cells, in contrast to CD8+ T cells, are remarkably well retained with aging. Here, we show that low-affinity TCR engagement is the main driving force behind the emergence and accumulation of naive-like CD4+ T cells with enhanced sensitivity to IL-2 in aged humans. In vitro, we show that these CD45RA(+) CD25(dim) CD4(+) T cells can develop from conventional naive CD25(-) CD4+ T cells upon CD3 cross-linking alone, in the absence of costimulation, rather than via stimulation by the homeostatic cytokines IL-2, IL-7, or IL-15. In vivo, TCR engagement likely occurs in secondary lymphoid organs as these cells were detected in lymph nodes and spleen where they showed signs of recent activation. CD45RA(+) CD25(dim) CD4+ T cells expressed a broad TCRVbeta repertoire and could readily differentiate into functional T helper cells. Strikingly, no expansion of CD45RA(+) CD25(dim) CD8+ T cells was detected with aging, thereby implying that maintenance of naive CD4+ T cells is uniquely regulated. Our data provide novel insight into the homeostasis of naive T cells and may guide the development of therapies to preserve or restore immunity in the elderly.

Cardiac arrhythmias are often associated with mutations in SCN5A the gene that encodes the cardiac paralogue of the voltage-gated sodium channel, NaV 1.5. The NaV 1.5 mutants R1193Q and E1784K give rise to both long QT and Brugada syndromes. Various environmental factors, including temperature, may unmask arrhythmia. We sought to determine whether temperature might be an arrhythmogenic trigger in these two mixed syndrome mutants. Whole-cell patch clamp was used to measure the biophysical properties of NaV 1.5 WT, E1784K and R1193Q mutants. Recordings were performed using Chinese hamster ovary (CHOk1) cells transiently transfected with the NaV 1.5 α subunit (WT, E1784K, or R1193Q), β1 subunit, and eGFP. The channels' voltage-dependent and kinetic properties were measured at three different temperatures: 10oC, 22oC, and 34oC. The E1784K mutant is more thermosensitive than either WT or R1193Q channels. When temperature is elevated from 22°C to 34°C, there is a greater increase in late INa and use-dependent inactivation in E1784K than in WT or R1193Q. However, when temperature is lowered to 10°C, the two mutants show a decrease in channel availability. Action potential modelling using Q10 fit values, extrapolated to physiological and febrile temperatures, show a larger transmural voltage gradient in E1784K compared to R1193Q and WT with hyperthermia. The E1784K mutant is more thermosensitive than WT or R1193Q channels. This enhanced thermosensitivity may be a mechanism for arrhythmogenesis in patients with E1784K sodium channels.

Summary Background Maternal smoking during pregnancy has been associated with increased risk of childhood overweight/obesity defined by body mass index (BMI). We examined its association with a range of adiposity measures and cardiovascular indicators in children aged 3–10 years. Methods We used data from a cross-sectional study of schoolchildren across mainland Portuguese districts (2009–2010). We applied quantile regressions to examine maternal smoking associations with adiposity (n = 17 286), blood pressure (BP) and resting pulse rate (RPR) (n ≈ 2500) measures across the age range, adjusting for prenatal and early life factors. Results Maternal smoking during pregnancy was associated with increases in offspring adiposity levels. The difference in median BMI between children of smokers and non-smokers was 0.39 kg m−2 (95% confidence interval: 0.25, 0.53) in boys and 0.46 kg m−2 (0.31, 0.62) in girls; 0.55 cm (0.24, 0.87) and 0.82 cm (0.45, 1.19), respectively, in median waist circumference; and 0.94 mm (0.49, 1.40) and 1.47 mm (0.87, 2.07) in median sum of (triceps, subscapular, suprailiac) skin-folds. The associations appeared to be stronger with increasing age. The differences in the 90th centile tended to be greater than those in median. There was no consistent association of maternal smoking with BP and RPR. Conclusions Children whose mother smoked during pregnancy had higher adiposity levels than children of non-smokers, across several measures, particularly among older children. Although there was no consistent association with cardiovascular indicators, maternal smoking association with childhood obesity may have implications for cardiovascular risk factors over the life course.

This article is dedicated to the rapid computation of separable expansions for the approximation of random fields. We consider approaches based on techniques from the approximation of non-local operators on the one hand and based on the pivoted Cholesky decomposition on the other hand. Especially, we provide an a-posteriori error estimate for the pivoted Cholesky decomposition in terms of the trace. Numerical examples are provided to validate and quantify the presented methods.

SUMMARY Background After the fall of the Taliban regime, most clinics in Afghanistan were charging fees to patients. The government invested in monitoring and evaluation systems for its newly rebuilt primary care system, but little was known about the effects of user fees. This study was undertaken to provide evidence on user fees' effects on quality and service utilization and to help inform development of health financing policy and strategy. Methods A quasi-experimental health financing pilot study was implemented in 2005. Forty-seven facilities were randomized to implement a standardized user fee intervention, offer free services, or serve as controls, continuing current cost-sharing systems. Revenues were co-managed by staff and community leaders for facility improvement. Baseline and follow-up facility assessments, exit interviews, and household surveys, as well as routine data were used to evaluate user fee effects over 2 years. Results Observed and perceived quality improved at most facilities but did not differ by study group. Utilization increased in all groups, but the increase was 682 to 748 visits per month larger in facilities randomized to free services compared with those randomized to fees or controls (p

Vagotomy, a severing of the peripheral axons of the vagus nerve, has been extensively utilized to determine the role of vagal afferents in viscerosensory signaling. Vagotomy is also an unavoidable component of some bariatric surgeries. Although it is known that peripheral axons of the vagus nerve degenerate and then regenerate to a limited extent following vagotomy, very little is known about the response of central vagal afferents in the dorsal vagal complex to this type of damage. We tested the hypothesis that vagotomy results in the transient withdrawal of central vagal afferent terminals from their primary central target, the nucleus of the solitary tract (NTS). Sprague-Dawley rats underwent bilateral subdiaphragmatic vagotomy and were sacrificed 10, 30, or 60 days later. Plastic changes in vagal afferent fibers and synapses were investigated at the morphological and functional levels by using a combination of an anterograde tracer, synapse-specific markers, and patch-clamp electrophysiology in horizontal brain sections. Morphological data revealed that numbers of vagal afferent fibers and synapses in the NTS were significantly reduced 10 days following vagotomy and were restored to control levels by 30 days and 60 days, respectively. Electrophysiology revealed transient decreases in spontaneous glutamate release, glutamate release probability, and the number of primary afferent inputs. Our results demonstrate that subdiaphragmatic vagotomy triggers transient withdrawal and remodeling of central vagal afferent terminals in the NTS. The observed vagotomy-induced plasticity within this key feeding center of the brain may be partially responsible for the response of bariatric patients following gastric bypass surgery.

The diagnosis of small fiber neuropathy (SFN) has been recently defined as typical symptoms due to small nerve fiber dysfunction accompanied by reduced intra-epidermal nerve fiber density (IENFD) or abnormal temperature threshold testing (TTT). Guidelines have been published for the assessment of IENFD. However, international guidelines for TTT are lacking. This paper presents a systematic literature review on reported TTT methods and provides recommendations for its future use in studies evaluating patients. A total of 164 papers fulfilled pre-defined requirements and were selected for review. Over 15 types of instruments are currently being used with a variety of methodological approaches for location, stimulus application, and sensation qualities examined. Consensus is needed to standardize the use of TTT as a diagnostic and follow-up tool in patients.

Esophageal motor function is highly coordinated between central and enteric nervous systems and the esophageal musculature, which consists of proximal skeletal and distal smooth muscle in three functional regions, the upper and lower esophageal sphincters, and the esophageal body. While upper endoscopy is useful in evaluating for structural disorders of the esophagus, barium esophagography, radionuclide transit studies, and esophageal intraluminal impedance evaluate esophageal transit and partially assess motor function. However, esophageal manometry is the test of choice for the evaluation of esophageal motor function. In recent years, high-resolution manometry (HRM) has streamlined the process of acquisition and display of esophageal pressure data, while uncovering hitherto unrecognized esophageal physiologic mechanisms and pathophysiologic patterns. New algorithms have been devised for analysis and reporting of esophageal pressure topography from HRM. The clinical value of HRM extends to the pediatric population, and complements preoperative evaluation prior to foregut surgery. Provocative maneuvers during HRM may add to the assessment of esophageal motor function. The addition of impedance to HRM provides bolus transit data, but impact on clinical management remains unclear. Emerging techniques such as 3-D HRM and impedance planimetry show promise in the assessment of esophageal sphincter function and esophageal biomechanics.

We compared on-station mortality, growth (mm), feed conversion, health parameters, and smolt-to-adult survival rate of spring Chinook salmon Oncorhynchus tshawytscha reared in baffled and standard (unbaffled) raceways. Fish reared in baffled raceways survived from release to adulthood at a rate 0.85 times that of fish reared in unbaffled raceways. There was no difference in percent on-station mortality (range, 0.00–0.001), health, or average length gained (1–12 mm) between fish reared in baffled and unbaffled raceways. Average feed conversion was constant (1.20–2.25) throughout the period of juvenile rearing and was similar between fish reared in baffled and unbaffled raceways, a finding supported by adiposomatic and hepatosomatic indices. Overall, we found similar on-station performance between fish reared in baffled and unbaffled raceways. The difference between SARs of fish reared in baffled versus unbaffled raceways was not statistically significant (P = 0.08). However, it is suggestive of a ...

In this article, the equivalent circuit model of an electro-absorption modulator (EAM) with planar isolated pedestal GSG contact is built to investigate the high-speed performances. A novel broadband impedance matching method for the microwave packaging of the EAM is presented. With this matching network, RF return loss can be great suppressed in a wide frequency range up to 40 GHz, along with an extended 3-dB bandwidth to 38.8 GHz. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2026–2032, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27040

Background The assessment of the esophagogastricjunction (EGJ) is the most challenging aspect of clin-ical esophageal manometry. Although conventionalmanometric systems can be optimized toward inter-rogating specific aspects of the EGJ, they are too lim-ited in recording channels and/or fidelity for acomprehensive assessment. The technological ad-vantages inherent in high resolution manometry(HRM) with esophageal pressure topography (EPT)analysis substantially change this equation providinga technology sufficiently robust to dynamically recordthe contractile activity within the EGJ with both goodfidelity and good spatial resolution.Purpose This review is an update on our under-standing of the application of HRM and EPT to theanalysis of EGJ function. With respect to sphincterrelaxation, the integrated relaxation pressure (IRP) hasproven to be a robust metric in differentiating intactfrom impaired EGJ relaxation. In the process, it re-vealed that impaired EGJ relaxation could occur notonly in the setting of achalasia but also with othercauses of EGJ outflow obstruction including hiatushernia. The morphological description of the EGJ byEPT has also revealed not only a spectrum of ab-normality ranging from an intact sphincter to overtherniation, but also the surprise finding of sponta-neous conversion among sphincter configurations,emphasizing its dynamic nature. With respect tobarrier function, preliminary data have refocused onthe crural diaphragm as a key-differentiating featurebetween preserved and compromised function. Fi-nally, although the accomplishments summarizedabove are substantial, much work remains to fullyexploit the potential of EPT in the clinical character-ization of the EGJ.Keywords esophagogastricjunction,gastro-esophagealrefluxdisease,loweresophagealsphincter,manometry.Abbreviations: CD, crural diaphragm; EGJ, esophagoga-stric junction; GERD, gastro-esophageal reflux disease;HRM, high resolution manometry; LES, lower esophagealsphincter.

This chapter summarizes the pros and cons of such alternative methods for detection of microorganisms in blood and discusses the perspectives of rapid molecular diagnosis of sepsis. Various methods have been assessed to reduce the time required for identification of microorganisms in blood cultures, including hybridization techniques, PCR-based applications, and spectrometric analysis. Among the hybridization techniques suited to identification of microorganisms in blood cultures are fluorescence in situ hybridization (FISH) and chemiluminescent probe matrices. To further reduce time to diagnosis of bloodstream infection (BSI), molecular methods may be applied directly to blood samples, without prior cultivation of microorganisms. Determination of susceptibility to antimicrobial treatment in sepsis is currently performed on cultured strains by determination of the MICs of a broad spectrum of different antibiotics. Current methods of molecular detection of sepsis concentrate on detection of DNA of the microorganism in the blood by both qualitative and quantitative approaches. In addition, alternative DNA extraction methods and multiplex PCR approaches are a first step towards point-of-care testing. For rapid detection of sepsis this is a promising approach, but a real implementation remains to be seen. Rapid molecular detection of the causative pathogen of sepsis is within reach, but many studies are required before clinical implementation. Several techniques are being tested for this application, but the best technique has not been determined. In general, all these promising tests will add to but not replace conventional blood culture as long as phenotypic susceptibility testing is needed.

To date there has been considerable work done in understanding and quantifying the lifetime and degradation of bulk heterojunction solar cells (BHJs) based on poly( para -phenylene vinylene) (PPV) [ 8–11 ] and poly(3-hexylthiophene) (P3HT) polymers. [ 12–15 ] A comparison of OPV lifetime experimental results across different research groups has posed challenges due to the lack of standardized testing and reporting procedures; however, great strides were made in this regard during the most recent International Summit on OPV Stability (ISOS-3). Modules based on P3HT/fullerene BHJs have shown lifetimes of 5000 h when state-of-the-art encapsulation with a glass-on-glass architecture is used. [ 16 ] Assuming negligible degradation in the dark and 5.5 h of one-sun intensity per day, 365 days per year, this translates into an operating lifetime approaching three years. More recently P3HT/PCBM devices utilizing an inverted architecture have been shown to retain more than 50% of their initial effi ciency after 4700 h of continuous exposure to one-sun intensity at elevated temperatures [ 17 ] and have exhibited a long shelf-life when stored in the dark in ambient conditions. [ 18 , 19 ]

To cite this article: Blumchen K, Bayer P, Buck D, Michael T, Cremer R, Fricke C, Henne T, Peters H, Hofmann U, Keil T, Schlaud M, Wahn U, Niggemann B. Effects of latex avoidance on latex sensitization, atopy and allergic diseases in patients with spina bifida. Allergy 2010; 65: 1585–1593. Abstract Background: Ten years ago, avoidance measures such as the performance of latex-free operations were implemented in children with spina bifida. Since then, latex sensitization and latex allergy have decreased in this high-risk group. Objective: To study the effect of primary latex-free prophylaxis on the prevalence of allergic diseases and atopy as a marker for sensitization spreading in children with spina bifida. Methods: One hundred and twenty children with spina bifida born after the introduction of latex-free prophylaxis and operated on under latex-free conditions (‘current group’) were examined for latex sensitization, latex allergy, sensitization to aero- and food allergens and allergic diseases. Results were compared to a ‘historic’ (not latex-free operated) group of children with spina bifida and comparable age (n = 87) and to a recent sample of children from the general population (n = 12 403). Results: In comparison with the ‘historic group’, latex sensitization (55%vs 5%, P

The syntheses of three linear condensation products of e-aminocaproic acid of a low degree of condensation, H[NH(CH2)5CO]xOH x = 3, 4 and 5, are described. The purification of these compounds has been accomplished by means of chromatographic adsorption.

Pathologic esophageal tumor length (pL) is an independent predictor of long-term survival. However, whether patients with longer (high-risk) tumors can be identified by endoscopy before surgery has not been established. The objective of the current study was to determine the value of endoscopically measured tumor length (cL) in predicting overall survival in patients with esophageal adenocarcinoma.All patients with esophageal adenocarcinoma who had undergone resection without neoadjuvant therapy and who had documented preoperative endoscopy findings were identified retrospectively by using prospectively collected databases at 2 institutions: The University of Texas M. D. Anderson Cancer Center (n = 164; training set) and University of Rochester Medical Center (n = 109; validation set). Esophageal tumors were assessed preoperatively by endoscopy for cL, depth (cT), and lymph node involvement (cN). Univariate and multivariate analyses of cL and other standard prognostic factors were performed.In the training set, cL was correlated directly with pL (Pearson correlation [r] = 0.683; P.001). Regression tree analyses suggested an optimum cutoff point of cL2 cm to identify patients with decreased long-term survival (5-year survival rate: cL2 cm, 29%; cL ≤ 2 cm, 78%; P.001). Multivariate Cox regression analysis demonstrated that cL2 cm was an independent risk factor for long-term survival (hazard ratio, 2.3; 95% confidence interval, 1.1-4.4; P = .02) even after controlling for age, cT, and cN. Validation with the validation dataset confirmed that cL was correlated directly with pL (r = 0.657; P.001) and predicted long-term survival using a cL cutoff point of2 cm (hazard ratio, 2.8; 95% confidence interval, 1.4-5.8; P = .004; univariate analysis).Endoscopic esophageal tumor length was identified as an independent predictor of long-term survival and may help to identify high-risk patients before they receive cancer-directed therapy.

The study investigates the effects of mandatory political representation of women and non-forward castes in India (73rd Constitutional Amendment) on development preferences and social equity. We used systematic content analysis of proceedings from meetings of 155 rural village assemblies. The study revealed overemphasis on physical infrastructure, relative neglect of health and education, influence of state government directives and marginalization of gender issues. However, there was higher likelihood of articulation of non forward caste-related issues by non-forward caste chairpersons. A paradigm shift in the development perspective of local governments, stressing investments in leadership development is needed. Copyright © 2009 John Wiley & Sons, Ltd.

The diffuse adsorption model accounts adequately for the adsorption of mixtures of direct dyes by cellulose if no interaction occurs between the dyes in either phase and if allowance is made for ionised carboxyl groups in the cellulose.

SUMMARY The Ministry of Public Health (MOPH) of Afghanistan has adopted the Balanced Scorecard (BSC) as a tool to measure and manage performance in delivery of a Basic Package of Health Services. Based on results from the 2004 baseline round, the MOPH identified eight of the 29 indicators on the BSC as priority areas for improvement. Like the 2004 round, the 2005 and 2006 BSCs involved a random selection of more than 600 health facilities, 1700 health workers and 5800 patient-provider interactions. The 2005 and 2006 BSCs demonstrated substantial improvements in all eight of the priority areas compared to 2004 baseline levels, with increases in median provincial scores for presence of active village health councils, availability of essential drugs, functional laboratories, provider knowledge, health worker training, use of clinical guidelines, monitoring of tuberculosis treatment, and provision of delivery care. For three of the priority indicators—drug availability, health worker training and provider knowledge—scores remained unchanged or decreased between 2005 and 2006. This highlights the need to ensure that early gains achieved in establishment of health services in Afghanistan are maintained over time. The use of a coherent and balanced monitoring framework to identify priority areas for improvement and measure performance over time reflects an objectives-based approach to management of health services that is proving to be effective in a difficult environment. Copyright # 2008 John Wiley & Sons, Ltd.

This paper examines the impact of quality improvements in conjunction with user fees on the utilization and equality of outpatient services at a range of public sector health facilities in India. Project impact on outpatient visits was estimated via the difference-in-difference method using pooled time series visit data from project and control facilities. The results indicate that the quality improvements significantly increased visits at all facility types. The project effect was largest at primary health center (PHC) and community health center (CHC), followed by district hospital (DH) and female district hospital (FDH). Pro-rich inequalities in outpatient visits increased at DHs and FDHs while at CHCs and PHCs the distribution remained equitable. This suggests that quality improvements at public sector health facilities can increase utilization of outpatient services in the presence of nominal user fees, but can also promote greater inequality favoring the better-off. At the referral hospital level, quality improvements should be made in conjuction with programs which encourage utilization by the poor. In contrast, the benefit of quality improvements at PHCs and CHCs is equitably distributed.

At times, total dissolved gas concentrations in the Columbia and Snake rivers have been elevated due to involuntary spill from high spring runoff and voluntary spill used as a method to pass juvenile salmonids over dams. The goal of this project was to determine if acute exposure to total dissolved gas supersaturation (TDGS) affects the reproductive performance of female chinook salmon late in their maturation. During this study, adult female spring chinook salmon were exposed to mean TDGS levels of 114.1% to 125.5%. We ended exposures at first mortality, or at the appearance of impending death. Based on this criterion, exposures lasted from 10 to 68 h and were inversely related to TDGS. There was no effect of TDGS on pre-spawning mortality or fecundity when comparing treatment fish to experimental controls or the general hatchery population four to six weeks after exposures. Egg quality, based on egg weight and egg diameter, did not differ between treatment and control fish. Fertilization rate and survival to eyed-stage was high ( > 94%) for all groups. With the exception of Renibacterium salmoninarum (the causative agent of bacterial kidney disease; BKD), no viral or bacterial fish pathogens were isolated from experimental fish. The prevalence (about 45%) and severity of R. salmoninarum did not differ among the groups or the general hatchery population. We conclude that these acute exposures to moderate levels of gas-supersaturated water—perhaps similar to that experienced by immigrating adult salmon as they approach and pass a hydropower dam on the Columbia River—did not affect reproductive success of female chinook salmon late in their maturation. These results are most applicable to summer and fall chinook salmon, which migrate in the summer/fall and spawn shortly after reaching their natal streams. Published in 2004 by John Wiley & Sons, Ltd.

The presence of adults with mental health and substance abuse disorders within the criminal justice system has become increasingly evident over the past decade. Interventions and treatment services have been designed and research conducted in an effort to establish evidence-based practices that effectively address the complex needs of this population. However, adopting and implementing these evidence-based interventions and practices within the real-world setting of criminal justice environments is challenging. This article reviews the research literature related to evidence-based treatment practices for offenders with co-occurring mental health and substance abuse disorders and explores the inherent challenges of fitting these interventions and services within criminal justice settings.

The Mectizan Donation Program (MDP) has been perceived as a highly effective public health programme, and as a possible model for addressing future problems in international health. This evaluation examines how the MDP partnership has been functioning from the perspectives of partner organizations. The results of a survey of 25 partners show that the perceived benefits far outweigh the problems, and that the direct costs to the organizations have been minimal. The partnership is rated highly on many aspects of governance and management, with relatively few problems identified. A factor analysis demonstrated that a wide range of factors have influenced the partners' perceptions. The benefits with the largest weights appear to be those related to external perceptions of the organization, and those indicating that the organization feels that its opinions will matter and lead to action in the partnership. The biggest factors influencing the positive perceptions on the governance and management of the MDP partnership appear to be the involvement of senior leaders from different organizations, and being able to agree on priorities. The MDP has been able to involve a large and heterogeneous number of partner organizations through relatively informal mechanisms that rely on goodwill and reciprocity. The survey results show how there was a strong alignment of the MDP with the interests of the various partners, and that a manageable number of problems were addressed and services provided. While having long-term goals, the MDP and the onchocerciasis control programmes have been effective at demonstrating the effectiveness of the approach through regular, professional, and outcome-oriented evaluations. Although the MDP is considered to be central to concerns of national officials, this feature is not rated as high as public perceptions, the internal characteristics of the partnership, or its accomplishments. Similarly, the need to secure resources is not viewed as a major determinant of the partnership's success, perhaps because resources were readily available through Merck and the partner organizations and programmes. These findings, along with the strategic and operational success of the MDP confirm the view that this type of public-private partnership should be pursued vigorously in other areas of public health. Other potential partnerships would do well to examine the characteristics of the MDP partnership, with careful attention to the features of its governance and the management, including a strong alignment of interests with partners, balancing a long-term vision with clarity of roles and intensive management of coordination, and professional and results-oriented accountability.

Predicting the long-time, nonequi- librium dynamics of receptor-ligand interactions for structured proteins in a host fluid is a formi- dable task, but of great importance to predicting and analyzing cell-signaling processes and small molecule drug efficacies. Such processes take place on timescales on the order of milliseconds to sec- onds, so "brute-force" real-time, molecular or atomic simulations to determine absolute ligand-binding rates to receptor targets and over a statistical en- semble of systems are not currently feasible. In the current study, we implement on real protein sys- tems a previously developed 3-5 hybrid molecular dynamics/Brownian dynamics algorithm, which takes advantage of the underlying, disparate time- scales involved and overcomes the limitations of brute-force approaches. The algorithm is based on a multiple timescale analysis of the total system Ham- iltonian, including all atomic and molecular struc- ture information for the system: water, ligand, and receptor. In general, the method can account for the complex hydrodynamic, translational-orientational diffusion aspects of ligand-docking dynamics as well as predict the actual or absolute rates of ligand binding. To test some of the underlying features of the method, simulations were conducted here for an artificially constructed spherical protein "made" from the real protein insulin. Excellent compari- sons of simulation calculations of the so-called grand particle friction tensor to analytical values were obtained for this system when protein charge ef- fects were neglected. When protein charges were included, we found anomalous results caused by the alteration of the spatial, microscopic structure of water proximal to the protein surface. Protein charge effects were found to be highly significant and consistent with the recent hypothesis of Hop- pert and Mayer (Am Sci 1999;87:518 -525) for charged macromolecules in water, which involves the forma- tion of a "water dense region" proximal to the charged protein surface followed by a "dilute water region." We further studied the algorithm on a D-peptide/HIV capside protein system and demon- strated the algorithms utility to study the nonequi- librium docking dynamics in this contemporary problem. In general, protein charge effects, which alter water structural properties in an anomalous fashion proximal to the protein surface, were found to be much more important than the so-called hydro- dynamic interaction effects between ligand and re- ceptor. The diminished role of hydrodynamic inter- actions in protein systems allows for a much simpler overall dynamic algorithm for the nonequilibrium protein-docking process. Further studies are now underway to critically examine this simpler overall algorithm in analyzing the nonequilibrium protein- docking problem. Proteins 2003;52:339 -348.

The uptake of Gadomer-17, as probed by fast dynamic T(1) measurements, was used to assess the vascular permeability surface-area product per leakage volume of tissue (k(Tofts)) of human glioma xenografts implanted in mice. With this approach we could discriminate between two types of glioma xenograft lines with a known difference in the perfused vascular architecture and degree of hypoxia. The T(1) data were analyzed according to the Tofts-Kermode compartment model. The fast-growing E102 tumor demonstrated a homogeneous distribution of the vascular permeability surface area across the tumor (mean k(Tofts) value = 0.18 +/- 0.05 min(-1)). The slowly growing E106 tumor showed a more heterogeneous pattern. Three perfused tumor areas with differences in vascular permeability surface area could be distinguished: a well-perfused periphery with high k(Tofts) values (0.24 +/- 0.04 min(-1)), perfused capillaries inside the tumor with low k(Tofts) values (0.108 +/- 0.026 min(-1)), and perfused capillaries adjacent to necrotic regions with high k(Tofts) values (0.29 +/- 0.10 min(-1)). On a different series of tumors, the hypoxic fractions were measured, and these were significantly higher in E106 tumors (0.14 +/- 0.05) compared to tumors of the E102 line (0.03 +/- 0.02).

OBJECTIVE To characterize the species of synovial fluid (SF) fibronectin (FN) bearing the alternatively spliced EIIIA segment. METHODS SF from patients with osteoarthritis (OA) and rheumatoid arthritis (RA), as well as corresponding affinity isolation products, were subjected to 1-dimensional and 2-dimensional electrophoresis followed by Western blot analysis. RESULTS Regardless of the clinical type of arthritis, a polyclonal antibody that recognizes antigenic determinants throughout the FN molecule produced staining of predominantly approximately 200+ and approximately 170-kd species in reduced 1-dimensional electrophoresis. Despite the overall prevalence of the larger species, 4 monoclonal antibodies (mAb) reactive with sequences lying near the center of the EIIIA segment exhibited a relative failure to recognize the larger of these 2 species in OA, but not RA, SF. The absence of recognition of EIIIA sequences within the approximately 200+ kd forms of OA SF FN was unrelated to their derivation from dimers, since anti-EIIIA mAb recognized the smaller fragment species in preference to both monomeric and dimeric forms. The approximately 170-kd EIIIA+ fragments were observed to have minimal gelatin-binding capacity and appeared on 2-dimensional electrophoresis to extend from the N-terminus of FN through at least the center of the EIIIA segment. Similar results were obtained for samples obtained by needle aspiration or arthroscopic lavage, suggesting a widespread applicability of these findings. CONCLUSION The approximately 170-kd EIIIA+ species of FN could potentially constitute a soluble "vehicle" by which chondrocyte-regulating EIIIA sequences, liberated from inhibitory flanking C-terminal sequences, could reach cells in the arthritic joint. Additionally, "FN species-specific" recognition of this segment within OA SF could constitute a marker by which to gauge the activity of the OA disease process.

The aim of this study was to investigate the swelling properties and the biocompatibility of a novel tissue expander material. The self-inflating material is a hydrogel consisting of a modified copolymer of methylmethacrylate and N-vinyl-2-pyrrolidone, which takes up water by osmosis. To increase the swelling volume, the primarily neutral gel material was modified by converting it into an ionized gel. To study the swelling and pressure behavior of the material, the anhydrous gel cylinders were equilibrated in distilled water, saline, and sugar solutions. The biocompatibility was investigated in cell culture. We tested the hydrogel eluate after swelling for cytotoxicity and mutagenicity using the cell lines MRC-5 and P3X63 Ag8 653 (Ag8). Furthermore, particles of the material were added to cell cultures to induce foreign body reactions and to verify its influence on monocyte differentiation. The material has a swelling capacity (Q = maximum swelling volume/anhydrous volume) of 5 to 50 depending on the degree of ionization of the polymer network. In this study, two polymer modifications with a swelling equilibrium of Q = 11.1 and 30 in water were tested. The swelling ratio also depends on concentration and ion content of the equilibration medium. The highest swelling capacity was found in water, the lowest in Ringer's solution. The swelling of the anhydrous material with the swelling capacity of Q = 11.1 fits best the average purpose of material properties for tissue expansion and generates a maximal hydrostatic pressure of approximately 235 mmHg. Effects on cell proliferation were detected only at the highest eluate concentration tested (i.e., eluate: culture medium = 1:1), which was far beyond physiological values, whereas mutagenicity was absent. Monocytes neither migrated nor tightly attached to the hydrogel. They neither phagocytose the material nor did they show any sign of a foreign body reaction, e.g., formation of multinucleated giant cells or monocyte proliferation. In the presence of hydrogel material, the differentiation processes of monocytes to macrophages or dendritic cells, respectively, were found to be undisturbed. From these results, we conclude that there is a high biocompatibility of the expander material, which may be a favorable and interesting candidate for further clinical applications.

Plankton communities in oligotrophic waters are characteristically dominated by the biomass of heterotrophs, including bacteria, micro-, and macrozooplankton. It has been generally assumed that these inverted biomass pyramids are the direct result of high specific production rates of phytoplankton and a tight coupling between producers and consumers. There are, however, at least two alternative hypotheses: (1) heterotrophic biomass turnover is much slower in oligotrophic than eutrophic systems; and (2) oligotrophic planktonic communities are significantly subsidized by allochthonous organic matter. In this study we assessed these hypotheses by establishing the relationship between plankton biomass structure (partition between auto- and heterotrophs), plankton function (plankton primary production and respiration) and whole-lake gas (O2 and CO2) fluxes in 20 temperate lakes that span a large range in primary production. We show that the balance of phytoplankton production and community respiration (P/R rat...

The medial preoptic nucleus (MPN) is an essential site for the regulation of male sexual behavior. Previous studies using c-fos as a marker for neural activation have shown that copulation increased c-fos expression in the MPN. Neural activation was also present in brain regions that are connected with the MPN and are involved in male sexual behavior, including the posteromedial bed nucleus of the stria terminalis (BNSTpm), posterodorsal preoptic nucleus (PD), posterodorsal medial amygdala (MEApd), and parvocellular subparafascicular thalamic nucleus (SPFp). The present study investigated whether the copulation-induced, activated neurons in these brain regions are involved in the bidirectional connections with the MPN. Therefore, mating-induced Fos expression was combined with application of anterograde (biotinylated dextran amine) or retrograde (cholera toxin B subunit) tracers in the MPN. The results demonstrated that neurons in the BNSTpm, PD, MEApd, and SPFp that project to the MPN were activated following copulation. However, in males that displayed sexual behavior but did not achieve ejaculation, few double-labeled neurons were evident, although both retrogradely labeled neurons and Fos-immunoreactive cells were present. In addition, retrograde neurons that expressed Fos were located in discrete subdivisions within the brain regions studied, where Fos is induced after ejaculation. Likewise, anterogradely labeled fibers originating from the MPN were not distributed homogeneously but were particularly dense in these discrete subdivisions. These results demonstrate that copulation-induced Fos-positive neurons in specific subdivisions of the BNSTpm, PD, MEApd, and SPFp have bidirectional connections with the MPN. Taken together with previous findings, this supports the existence of a discrete subcircuit within a larger neural network underlying male sexual behavior.

This paper describes early experience with the Sector-Wide Approach (SWAp), an emerging trend in development practice in low-income countries. The paper describes what a SWAp is, and why it is now being pursued. The SWAp is characterized as a sustained government-led partnership with donor agencies and other groups. By applying sector-wide policies to an expenditure framework and national implementation systems, explicit health sector reforms are undertaken to meet sectoral and national development objectives. The approach has changed the dynamic between governments and donor agencies, requiring systemic changes in policy-making and management in both governments and donor agencies. With the SWAp, ongoing joint assessment and negotiations around sectoral plans and review of performance replaces the old way of preparing and supervising projects. Early experiences in countries undergoing SWAps are discussed, including the problem of reconciling priority programs and old practices with broader health sector reforms and new ways of managing development assistance. The paper concludes by identifying some of the key challenges for the future of SWAps. © 1998 John Wiley & Sons, Ltd.

A new model for studying the initial events of granuloma formation in vitro is presented using heat killed Candida albicans immobilized on the surface of plastic culture wells. Human monocytes were induced to accumulate and to proliferate, forming multinucleated giant cells (MGC) and epitheloid cells within 4 days of culture. Tumour necrosis factor-alpha (TNF-alpha), interleukin (IL)-1 beta and IL-6 were detected in culture supernatants. These monokines, and additionally macrophage colony stimulating factor (M-CSF), were also detected immunocytochemically. The granuloma formation was inhibited by Dexamethasone (Dex), Pentoxifylline (POF), or interferon-gamma (IFN-gamma) in a dose-dependent manner. Antibodies to M-CSF reduced the granuloma formation to a great extent with a striking reduction of monocyte proliferation. Using antibodies to TNF-alpha the authors found a complete inhibition of the granuloma including MGC formation and monocyte proliferation.

The tremendous growth in state and federal correctional populations has focused greater attention on the needs of mentally ill and substance abusing inmates. Although an estimated 3-11% of prison inmates have co-occurring mental health (psychotic and major mood) disorders and substance abuse disorders, few treatment programs are described in the literature and there is little available information regarding effective treatment strategies for this population. The current study provides an integrative review of seven 'dual diagnosis' treatment programs that recently have been developed in state and federal prisons. Many of these have evolved from existing substance abuse treatment programs and approaches. Key program components include an extended assessment period, orientation/motivational activities, psychoeducational groups, cognitive-behavioral interventions such as restructuring of 'criminal thinking errors', self-help groups, medication monitoring, relapse prevention, and transition into institution or community-based aftercare facilities. Many programs use therapeutic community approaches that are modified to provide (a) greater individual counseling and support, (b) less confrontation, (c) smaller staff caseloads, and (d) cross-training of staff. Research is underway in three of the seven sites to examine the effectiveness of these new programs.

The time courses of uptake, distribution, and excretion of radioactive PO, were determined for 11 species of freshwater algae. Uptake of PO, by algae was rapid, reaching a steady-state asymptote within an hour and maintaining that maximum for at least 10 h. Uptake could be described as a biphasic exponential function. The rate constants for uptake decreased with cell volume raised to a power of - -0.25, whereas the uptake rates per cell increased with cell size to a power of -0.75, suggesting that small cells were much more efficient at sequestering PO,. Excretion of PO, by algae was fast during the first lo-20 min; thereafter, there was a slower prolonged loss of PO, for the remaining period. A two-compartment model could be convincingly fitted directly to the excretion time-course data. Both rate constants and flux rates of PO, excretion and intercompartmental exchanges showed a similar size-dependency to those of PO, uptake. The net uptake of PO, by algae increased proportionately to cell volume raised to a normalized power of 0.75. The allometric compartment model yielded estimates for net PO, uptake rates one order of magnitude higher than those determined by means of the Michaelis-Menten model.

Interpersonal affect has been found, in prior laboratory research, to be related to ratings of job performance. Such findings have been taken to mean that affect creates bias in ratings. The present study was conducted to determine if this relationship would hold up in a field setting. The present study was also designed to examine how structured diary-keeping, and the nature of the appraisal instrument, might be related to affect-appraisal relationships. The results for 85 raters, and 404 ratees, suggested that affect was significantly related to all ratings, but more strongly related to trait-like ratings than task/outcome-like ratings, and that having raters keep performance diaries actually increased the strength of the relationship between affect and ratings. We concluded that affect may not be a biasing influence on ratings, but may be a result of better subordinate performance. Results from an analysis of the diary content supported this conclusion. Implications for the role of affect on ratings and the nature of the relationship between past performance and interpersonal affect in field settings are discussed.

Although rates of P and N excretion by zooplankton have important implications for nutrient cycling in aquatic ecosystems, the literature offers few quantitative general models of these processes. We used data collected from published studies to construct potentially predictive models of P and N excretion rates by zooplankton from freshwater and marine habitats. Excretion rates of P and N are strongly correlated (r2 = 0.88) and consequently each predicts the other best. Respiration rate is also highly significantly correlated with P and N excretion rates and is the second best predictor. Although body size explained relatively less overall variability, the inclusion of temperature, container volume, and experimental duration as independent variables in multiple regressions substantially improved the predictive power of models based on body size. The models can be corrected for taxonomic biases in zooplankton, but these biases were usually small. These models could provide both a basis for further empirical analysis of the determinants of zooplankton nutrient excretion and a means of predicting the fate of nutrients in aquatic ecosystems.

A comparative analysis of planktonic metabolism in 20 southern Quebec lakes was carried out to test the hypothesis that planktonic P: R ratios reflect gradients of both nutrient enrichment and dissolved organic carbon (DOC). Mean epilimnetic phytoplankton photosynthesis ranged from 8 to 377 mg C m-3 d-l, and the amount of C respired by the plankton in excess of phytoplankton photosynthesis ranged from 30 to 86 mg C m-3 d-l. Plankton community respiration was 2-8 times greater than phytoplankton photosynthesis in all oligotrophic and mesotrophic lakes during the growing season, and this imbalance narrowed toward the more productive lakes. P: R ratios were positively related to chlorophyll and total P concentration, and inversely related to water color and DOC concentration. The strong influence of DOC on planktonic P: R ratios was almost exclusively due to its depressing effect on phytoplankton photosynthesis; DOC had no statistical effect on respiration. The calculated DOC loading for these lakes suggests that organic C loss through epilimnetic respiration in excess of phytoplankton photosynthesis is comparable to the estimated DOC loss within the lakes and that summer plankton metabolism could be supported by external DOC inputs in most lakes. The highly significant intercept of the respiration to production relationship, 27 mg C m-3 d-l, may indicate the baseline metabolism supported by external sources of C that occurs in these temperate lakes. Estimates of respiratory CO2 production from the pelagial of these lakes range from 11 to 60 mmol CO, m-2 d-l, depending on lake trophy and DOC concentration. These estimates suggest that the planktonic metabolism of allochthonous DOC probably constitutes a major source of CO, in lakes.

To investigate the differentiation and activation of monocytes, the combined effects of 1,25-dihydroxyvitamin D3 (D3) and IL-4 on human blood monocytes were examined with respect to expression of MHC class-II antigens, accessory activity, and phagocytic capacity. IL-4 was reported to upregulate the expression of MHC class-II antigens and accessory activity of monocytes. The experiments described here demonstrate that D3 inhibits the expression of all three subtypes of MHC class-II antigens (HLA-DR, -DP and -DQ) as well as the accessory activity of monocytes, both in a dose- and time-dependent manner. However, D3 enhances the immunoglobulin- and complement-dependent phagocytosis by monocytes in a dose- and time-dependent manner. When monocytes are treated with both IL-4 and D3, the effects of D3 are reverted by IL-4, suggesting that IL-4 induces the development of monocytes into accessory cells, whereas D3 stimulates differentiation of monocytes into classical macrophages. These findings provide further evidence for the contention that, depending on defined stimuli, monocytes may develop either into accessory cells or into classical macrophages.