Using CDOM spectral shape information to improve the estimation of DOC concentration in inland waters: A case study of Andean Patagonian Lakes.

For the last two decades different scientific disciplines have focused on lacustrine dissolved organic matter (DOM) given its importance in the biogeochemistry of carbon and in ecosystem functioning. New satellites supply the appropriate resolutions to evaluate chromophoric dissolved organic matter (CDOM) in inland waters, opening the possibility to estimate DOM at appropriate spatiotemporal scales. This requires, however, a robust relationship between CDOM and dissolved organic carbon (DOC). In this work, we evaluated the use of CDOM as a proxy of DOC in 7 Andean Patagonian lakes. Considering the entire data set, CDOM absorption coefficients (a355 and a440) were linearly related with DOC. Shallow lakes, however, drove this relationship showing a moderate relationship, whereas, deep lakes with lower colour presented a weaker relationship. Therefore, we assessed the use of CDOM spectral shape information to improve DOC estimates regardless of observed DOM differences due to climatic seasonality and lakes' morphometry. The use of well-known CDOM spectral shape metrics (i.e., S275-295 and a250:a365 ratio) significantly improved DOC estimation. Particularly, using a Gaussian decomposition approach we found that much of the variation in the spectral shape, associated with the variability of CDOM:DOC ratio, was explained by differences in two dynamic regions centred at 270 and 320 nm. A strong nonlinear relationship was found between the a270:a320 ratio and the DOC-specific absorption coefficients a*355 and a*440. This was translated into a further improvement in DOC estimation yielding the higher R2 and lower mean absolute differences (MAPD < 16%), either considering the entire data set or shallow and deep lakes separately. Our results highlight that incorporating the CDOM spectral shape information improves the characterization of the DOC pool of inland waters, which is particularly relevant for remote and/or inaccessible sites and has significant implications for the environmental management, biogeochemical studies and future remote sensing applications.

Covariation patterns of phytoplankton and bacterioplankton in hypertrophic shallow lakes.

The aim of this work was to assess the temporal patterns in the community composition of phytoplankton (PCC) and bacterioplankton (BCC) in two interconnected and hypertrophic Pampean shallow lakes in Argentina. Factors shaping their community dynamics and community temporal covariations were also analysed. We performed 4 years of seasonal samplings (2012-2016) and communities were studied by the Utermöhl approach (PCC) and Illumina MiSeq sequencing (BCC). We found marked seasonal variations in both communities and inter-annual variations with decreasing microbial community similarities during the study. We also observed covariation in community-level dynamics among PCC and BCC within and between shallow lakes. The within-lake covariations remained positive and significant, while controlling for the effects of intrinsic (environmental) and extrinsic (temporal and meteorological) factors, suggesting a community coupling mediated by intrinsic biotic interactions. Algal-bacterial associations between different taxa of phytoplankton and bacterioplankton within each lake were also found. PCC was mainly explained by pure regional extrinsic (17-21%) and intrinsic environmental (8-9%) factors, while BCC was explained by environmental (8-10%) and biotic interactions with phytoplankton (7-8%). Our results reveal that the influence of extrinsic regional factors can be channeled to bacterioplankton through both environmental (i.e. water temperature) and phytoplankton effects.

Fluorescence components of natural dissolved organic matter (DOM) from aquatic systems of an Andean Patagonian catchment: Applying different data restriction criteria for PARAFAC modelling.

Fluorescence spectroscopy is a widely applied technique to characterize the composition of the fluorescent fraction of dissolved organic matter (DOM), allowing to infer sources and diagenetic state of soil, marine and freshwater DOM samples. The analysis of fluorescent DOM (FDOM) is often carried out by multi-way models such as parallel factor analysis (PARAFAC), which allows decomposing excitation-emission matrices (EEMs) obtained from DOM samples into their underlying chemical components. Some aspects of the performance/accuracy of the EEM-PARAFAC technique regarding the use of selective vs. non-selective EEM data are still in discussion. In this investigation, we evaluated the outcome of two different approaches (non-selective and selective) applied to study the composition of DOM from four headwater streams (Case 1) and from two neighboring shallow lakes (Case 2), all belonging to the same Andean watershed within Nahuel Huapi National Park in North Patagonia (Argentina). In both cases, the outcome of the PARAFAC performed to non-selective data (EEM datasets from all the streams and the two lakes) vs. selective datasets (EEMs from each stream and each lake treated separately) is compared on the basis of modelled fluorescent components. Regardless of the restriction criteria applied for the analyses, the results obtained indicated similar component loadings in the four streams and in the two lakes. The similarity of the outcomes likely relates to the low internal variation of the EEMs, since these are located in the same catchment, influenced by similar soils and vegetation which are the main DOM sources. Therefore, we conclude that the use of a small selective EEM dataset may not condition the validation of the FDOM components and their temporal dynamics.

[Percutaneous extracorporeal circulation in cardiogenic shock caused by combined poisoning with methyldigoxin, nifedipine and indapamide]. / Perkutane extrakorporale Zirkulation bei kardiogenem Schock aufgrund einer Mischintoxikation mit Metildigoxin, Nifedipin und Indapamid.

HISTORY AND FINDINGS: A 38-year-old man with endogenous depression was found comatose and with gasping respiration. Empty packets of tablets pointed to poisoning with methyldigoxin, nifedipine and indapamide. Pupils reacted slowly to light and no peripheral blood pressure could be measured. TREATMENT AND COURSE: Routine resuscitation measures (intubation, mechanical ventilation, external cardiac massage and drugs) were undertaken during transport to hospital where, in addition to further symptomatic treatment, digoxin antibodies were administered, but without noticeable effect. Percutaneous cardiopulmonary bypass was therefore undertaken. It achieved a cardiac output of 3.2l and a systolic pressure of 80 mm Hg: a stable rhythm and circulation were obtained within 15 hours indicating that electromechanical uncoupling had for the time being been overcome. The EEG suggested a midbrain syndrome. After another 18 hours of mechanical ventilation and symptomatic treatment asystole suddenly occurred. Renewed resuscitation procedures were not undertaken because of the very poor neurological state and prognosis. CONCLUSION: Although haemodynamic stabilization was only temporarily achieved and the patient's death could not be prevented because of adverse pretreatment conditions, the application of percutaneously implantable, transportable heart-lung machine appears to be justified in cases of intoxication with cardio- and vasodepressive substances.

[The use of a percutaneously connected heart-lung machine during resuscitation in cardiogenic shock after acute myocardial infarct]. / Einsatz einer perkutan anschliessbaren Herz-Lungen-Maschine unter Reanimationsbedingungen im kardiogenen Schock bei akutem Herzinfarkt.

A 47-year-old man was referred by an emergency physician to the intensive care unit of a hospital under resuscitation conditions while having recurrent attacks of ventricular fibrillation. Coronary angiography, performed while resuscitation measures had to be maintained, revealed severe three-vessel disease with occlusion of the anterior interventricular branch at its origin. Electrical and haemodynamic instability persisted even after thrombolysis with urokinase and introduction of an intraaortic balloon pump. Percutaneous partial cardiopulmonary bypass (CPB) was, therefore, instituted and a cardiac output of 2.5 1 achieved together with a stable sinus rhythm and a systolic pressure of 60-80 mm Hg. After 9 h on CPB, drug administration could be levelled off and he was mobilised. He showed no neurological deficits and 4 months later he underwent an elective coronary bypass operation. This report demonstrates that even in conditions of resuscitation mechanical circulatory support can be undertaken rapidly and successfully, in the face of electrical instability, to achieve at least temporarily a stable circulation.

[Youths and alcohol--drinking behavior of young people]. / Jugend und Alkohol--zum Trinkverhalten Jugendlicher.

On the basis of several representative research findings of the Central Institute of Youth Research the drinking habits of young people are described. Besides the frequency of drinking, the weekly overall consumption of alcohol, the consumption of different kinds of alcoholic beverages as well as the combinations preferred were ascertained. A habitual daily alcohol intake of more than 40 g of pure alcohol was found among one fifth of the male workers up to the age of 35 and among 14 per cent of the male apprentices, but only among three per cent of the male intellectuals. We analyzed the conditions which encourage the abuse of alcohol on the societal and individual level as well as within social groups, and thus derived some conclusions for the prevention of alcohol abuse among adolescents. An effective reduction in the abuse of alcohol can--in the long term--only be achieved by a wide range of societal measures. The first step is to make the population more aware of the problems resulting from the abuse of alcohol.

[Development of smoking behavior in adolescents]. / Die Entwicklung des Rauchverhaltens Jugendlicher.

Based on several representative studies conducted by the Central Institute for Youth Research this analysis shows how smoking among young people has developed from 1970 to 1987. Since the early 80's the proportion of adolescent smokers has not increased further. Since that time, on average, smoking has not been taken up at a younger age either. The different proportions of smokers are most clearly determined by educational level and qualifications. The predominant motivation to heavy smoking is the pressure of the peer group. To prevent young people from starting to smoke an early "immunization" is essential. This requires a long-term strategy to promote non smoking and will involve a broad range of societal measures.

Influences of nutrition on immunity and susceptibility to mouse hepatitis virus type 2.

Resistance to mouse hepatitis virus (MHV) in C3H mice is a genetic trait which appears 3-4 weeks after birth. However, when these animals were weaned on a low protein diet (8% casein), they remained susceptible to MHV-2 infection until they reached 8-9 weeks of age. During this period, the protein-restricted C3H mice were as susceptible to MHV-2 as the genetically susceptible congenic C3Hss strain. The delay in the emergence of resistance in the protein-restricted mice could be corrected by injecting these animals with spleen cells from 6-week-old C3H mice. Thymocytes from normal C3H mice, and splenocytes and thymocytes from protein-restricted C3H mice, were not protective. However, spleen cells from the protein-restricted mice were more responsive to phytohaemagglutinin, lipopolysaccharide and concanavalin A than spleen cells from normal C3H. The enhanced lymphoproliferative response in spleen cells from protein-restricted mice was abrogated by the addition of plastic-adherent cells obtained from normal C3H spleens. Spleen cells from protein-restricted and from genetically susceptible C3Hss mice also possessed more spontaneous cytotoxicity against MHV-infected 3T3 fibroblasts.

Identification of viruses in the urine of renal transplant recipients by cytomorphology.

This study was designed to reassess the cytomorphology of viral infections in urinary cells obtained from renal transplant patients and to examine the association, if any, between these cytologic changes and the transplant rejection. A total of 2,354 cytologic specimens obtained from 91 renal transplant recipients was evaluated. A combination of techniques, including cellulosic filters, immunofluorescence, hemagglutination inhibition and electron microscopy, was utilized. Cytologic observations were correlated with the patient's clinical history. Thirty-eight patients revealed cytologic evidence of viral infections (herpes simplex, cytomegalovirus and papovavirus). These viral infections had distinct cytomorphology. Cytomegalovirus infection may manifest as intracytoplasmic, orangeophilic inclusions, in addition to the classical intranuclear inclusion. In the majority of renal transplant patients there appeared to be no relationship between the viral infection and the renal transplant rejection episodes.

Ultrastructure of the mucociliary interface in the nasal mucosa of the chicken.

The ultrastructure of the extracellular mucous blanket at the nasal cavities of the chicken was preserved by a method that stabilizes primarily carbohydrate moieties. The cilia were apparently fixed as if "frozen" in the act of beating. The blanket was markedly heterogeneous, with a basic fibrous structure, and it contained membrane remnants. The lumenal surface of the blanket was smooth, but the surface in contact with the cilia penetrated to varying depths between the ciliary shafts. The findings are discussed in terms of the assumptions made by others on the basis of indirect evidence.

Identification of an immunologically distinct papillomavirus from lesions of epidermodysplasia verruciformis.

Virions isolated from warts of 2 siblings with epidermodysplasia verruciformis (EV), a rare disease characterized by the lifelong growth of warty skin tumors containing papova-like virions, were compared to isolates of human papillomavirus (HPV) from 3 pools of plantar and common hand warts. The length of relaxed, circular (form II) molecules of EV virion DNA approximated the length of HPV DNA but was 3.3% longer. Antisera prepared in rabbits against the 3 HPV pools coated and aggregated HPV in immune electron microscopy (IEM) tests but did not react with EV virions. These antisera reacted at high titers in complement fixation (CF) tests with HPV and reacted only weakly in CF tests with EV virions. Rabbit antisera to EV virions coated and aggregated EV virions but reacted only weakly or not at all with HPV virions in IEM tests. These sera reacted in CF with EV virions only. The data indicated that virions from the EV patients represent an immunologically distinct papillomavirus.

Characterization of SA12 as a simian virus 40-related papovavirus of chacma baboons.

SA12 virus, originally isolated from an uninoculated South African vervet monkey kidney culture, was identified as a new member of the simian virus 40 (SV40)-polyoma subgroup of papovaviruses. The virus produced a cytopathic effect with nuclear enlargement in primary rhesus kidney cells. The virion had papovavirus morphology and a diameter of 44 to 45 nm. The DNA of the virus was a circular, double-stranded, superhelical molecule with a mean length 101% that of SV40 DNA and an estimated molecular weight of 3.3 X 10(6). The virus was found to be unrelated to other papovaviruses by neutralization, immune electron microscopy, and immunofluorescence tests with antiviral sera. SA12 virus-infected cells exhibited a capsid antigen, which has recently been found to be common to viruses of the SV40-polyoma subgroup. The virus readily transformed kideny cells from 10-day-old hamsters. Inoculation of transformed cells produced tumors in 3- to 4-week-old hamsters. The T antigens of SA12 and SV40 viruses were strongly and reciprocally cross-reactive. A high proportion of the sera of chacma baboons, Papio ursinus, and a comparatively lower proportion of the sera of vervet monkeys, Cercopithecus pygerythrus, had neutralizing antibodies to SA12 virus

Congenital transmission of a papovavirus of the stump-tailed macaque.

Stump-tailed macaque virus, a newly recognized papovavirus of the SV40 polyoma subgroup, was demonstrated in kidney cultures from each of five stump-tailed macaque fetuses in the second half of gestation and from six adult stump-tailed macaques. Such regular presence of virus in the fetus is an unusual feature for a papovavirus.

[Investigations on the extension of smoking among the working youth of the German Democratic Republic and on the smoking habits of Leipzig Youth]. / Zur Verbreitung des Rauchens unter der werktätigen Jugend der DDR und zum Rauchverhalten Leipziger Jugendlicher.

In an extensive study performed in 1975 the extent of smoking among 4000 working adolescents of GDR was analysed. The results are approximately representative for the whole working youth of GDR in the age period of 17 to 25 years. The portion of smokers is represented approximately in dependence on socio-demographic factors and on social positions. The main results are as follows. 45% of the working youth in GDR are smokers; 55% being among male adolescents and 36% among female ones. The increasing extension of smoking habits must be first of all attributed to the growing proportion of female smokers. From all seizable influencing factors the levels of education and qualification have the most significant effect to the proportion of smokers to nonsmokers, the percentage of smokers significantly decreasing with increasing level of education and qualification. More detailed data on the smoking habits of adolescents are based on a longitudinal study of the Zentralinstitut für Jugendforschung begun in 1968 and continued every year in the same population investigating the development of the personality of adolescents and its determination in 600 Leipzig pupils of the 6th form. Onset of smoking, occasional and habitual smoking, average cigarette consumption per day and motivation for nonsmoking are analysed. Conclusions are drawn from these investigations for the prevention of smoking.

Identification of the stumptailed macaque virus as a new papovavirus.

A new viral agent, stumptailed macaque virus (STMV), isolated from uninoculated stumptailed macaque kidney cultures was identified. The virions had the size and morphology of papovaviruses of the simian virus 40 (SV40)-polyoma subgroup, but many of them appeared to have an additional outer envelope. The deoxyribonucleic acid of STMV was a superhelical circular molecule, with a mean length 91% of that of SV40. The antigenic relationship of this virus with other members of the group was examined by immune electron microscopy of isolated virions and by immunofluorescent staining of virus-infected cells. STMV was immunologically distinct from SV40, BK virus (BKV), polyoma virus, and JC virus. Its tumor antigen may be related to those of SV40 and BKV.