Growth of fungi and yeasts in food production waste streams: a feasibility study.

Food production produces nutrient-rich waste streams which, depending on local legislation, are either sent to wastewater treatment plants or discharged into the environment. In addition to causing environmental harm in the second instance, valuable nutrients are lost. A more circular approach would be to reuse these waste streams. Fungi and yeasts are ideal candidates as they require lots of organic carbon (which is especially high in food production waste streams) for growth, with the potential for producing value-added biomass. Here, we tested the metabolic activity and possible growth of seven fungi and three yeasts in five different food production waste streams. Initial tests were done to find the most promising waste streams for growth and these were chosen for further study. All species were then cultured in these waste streams and oxygen uptake was measured to gauge metabolic activity which we used as a proxy for growth rate. Pelletization's effect on metabolic rates was tested on the most pellet-forming species, by adding agar to inhibit pellet formation. The most promising waste stream for yeast/fungal growth was cheese whey (Whey). Pellet inhibition (i.e., filamentous growth) resulted in increased metabolic activity of cells in the confectionary bakery waste stream with agar but decreased metabolic activity in Whey with agar. The best-growing species, Geotrichum candidum, has potential commercial value as a producer of enzymes, biochemicals and lipids and could provide added value while improving the circularity of water and nutrients in food production.

Unwanted mainstream nitritation-denitritation causing massive N2O emissions in a continuous activated sludge process.

Nitrous oxide emissions can contribute significantly to the carbon footprint of municipal wastewater treatment plants even though emissions from conventional nitrogen removal processes are assumed to be moderate. An increased risk for high emissions can occur in connection with process disturbances and nitrite (NO2-) accumulation. This work describes the findings at a large municipal wastewater treatment plant where the levels of NO2- in the activated sludge process effluent were spontaneously and strongly increased on several activated sludge lines which was suspected to be due to shortcut nitrogen removal that stabilized for several months. The high NO2- levels were linked to a dramatic increase in nitrous oxide (N2O) emissions. As much as over 20% of the daily influent nitrogen load was emitted as N2O. These observations indicate that highly increased NO2- levels can occur in conventional activated sludge processes and result in high nitrous oxide emissions. They also raise questions concerning the risk of increased greenhouse gas (GHG) emissions of the nitritation-denitritation processes - although the uncontrolled nature of the event described here must be taken into consideration - and underline the importance of continuous monitoring and control of N2O emissions.

Data analytics in control and operation of municipal wastewater treatment plants: qualitative analysis of needs and barriers.

This study aims to identify barriers and needs for the application of data analytics in municipal wastewater treatment. The study was conducted through a series of interviews with stakeholders involved in instrumentation, control, and automation of wastewater treatment plants. Opportunities and limitations observed by different stakeholders were assessed with a thematic analysis. Thematic analysis enabled a broader consideration of social and organizational aspects related to process control, operation, and maintenance. Identified key barriers for applying data analytics included laborious instrumentation maintenance, unstable control loops, and deficient customization of digital tools for users at wastewater treatment plants. Development needs include easier data processing tools, quality assurance of instrumentation, and controller tuning. Results indicate that the perceived potential of data analytics is highly dependent on the performance of underlying physical and digital systems, as well as the control strategies and operating environment of the plant. Despite the barriers, users and developers see many potential applications for data analytics and expect them to have a central role in the control and operation of wastewater treatment plants in the future.

Full-Scale investigation of the influence of flow equalization and prefermentation on nitrification.

This article presents the findings on the effects of flow equalization and prefermentation on nitrification in a full-scale municipal plant. Existing primary clarifiers in one process train were modified for diurnal flow equalization and for a low-rate volatile fatty acid production. The performance of the biological process was compared with the parallel reference process train operated with conventional primary clarification. Only a few reports on the effects of equalization on nitrification have been published, but based on this limited knowledge, diurnal flow equalization was presumed to improve the nitrification performance. However, more constant flow conditions could not fully explain the improvements of autotrophic activity. The authors suggest that increased readily biodegradable organic matter played indirectly a role in nitrification performance. Moreover, stable flow conditions were reflected in improved sludge characteristics and offered, in addition to a levelling out of diurnal variations, a long-term buffer capacity against high hydraulic loadings.

Performance and microbial community structure of a full-scale ANITATMMox bioreactor for treating reject water located in Finland.

The aim of this work was to study the operational performance and the microbial community dynamics during the start-up of ANITATMMox technology implemented at full-scale wastewater treatment plant in Finland to treat reject water from anaerobic digesters. The average ammonium removal in the studied setup reached around 90%, withstanding ammonium loads up to 0.13 g N m-2h-1. The nitrite concentration in the effluent did not exceed 10 mg L-1, and there was a slight accumulation of NO3--N during the operation which was controlled. Thus, the result showed a robust success to high ammonium loading in presence of organic matter. The sequencing showed a heterogeneous microbial population where Methanosaeta, WCHA1-57 genus, Sphingobacteriia, Chlorobia and diverse unknown fungi were found as dominant phylotypes. Moreover, members of the Brocadiaceae family were dominant in the adhered biomass, mostly represented by Candidatus Scalindua, rarely reported in WWTPs. Overall, the results demonstrated a drastic effect of region-specific operational conditions on carrier biofilm microbial communities as it was demonstrated by the microbial studies.

The effect of flow equalisation and prefermentation on the sludge production and sludge characteristics in a BNR plant.

A full-scale study investigated the influence of diurnal flow equalisation and prefermentation on the characteristics of sludge. The diurnal variations in the sludge concentration and the level of sludge blanket in the secondary clarifiers were evened out significantly with the use of an equalization basin. Stable conditions in the aeration basin and in the secondary clarifiers contributed to the improvements in the performance of the BNR plant. A decrease in the waste activated sludge production and an improvement in the settleability were also observed. The low WAS yield was attributed to the low yield COD compounds produced by the prefermentation, longer sludge age and constant conditions obtained by the flow equalisation. Some evidence was found that good settling properties would be related to the amount of suspended solids fed to the biological process as well as to the good performance of the biological process.

The definition of depression.

Prevalence figures of depression usually show a sex ratio for males:females of 1:2. This unequal ratio has been examined by varying the time periods for the calculation of prevalance rates and the criteria for case definition. Based on results of a 20-23 yr-old cohort of 591 males and females studied in Switzerland, some evidence was found to support the hypothesis that an unequal sex ratio is partially due to unequal reporting of depressive symptoms and to differential forgetting, perhaps linked with the male role in society. It is not yet possible to extend the results of this study to older cohorts. Further research would be desirable.

Do the diagnostic criteria determine the sex ratio in depression?

The 1-year prevalence rates and sex ratio of dysphoric mood, brief (BDE, less than 2 weeks) and extensive (EDE, greater than or equal to 2 weeks) depressive episodes and major depression (RDC, DSM-III) from an epidemiologic study are presented. Factors influencing the sex ratio are analyzed: subjective suffering from EDE, social and work impairment were found to an equal degree in both genders. Factors favoring female preponderance: women report more symptoms, men most probably forget symptoms, frequency and length of less recent depressions more readily, women see a physician or proceed to self-medication much more often. Consequently, the identical minimum symptom number for both genders is questioned and occupational impairment suggested as an alternative case-defining criterion.

Swiss heroin-addicted females. Career and social adjustment.

Studies on gender-related differences among heroin-addicted individuals are uncommon because women usually make up only one quarter of any one sample group. In our sample group of 248 Swiss-German heroin-addicted individuals from different therapeutic programs and prisons, 70 were women (28.2%). Follow-up investigations were conducted after a lapse of 2 years, and after a lapse of 7 years, respectively. Men and women appear to differ with respect to why they begin to use drugs, as well as why they relapse back into drug use. Prior to the commencement of drug abuse, social background concerns and social adjustment dynamics appear to constitute a heavier burden for women than for men. Observations of social functioning and adjustment phenomena made during their drug careers and in the follow-up investigations, however, failed to yield significant statistical differences. The predominant effects of drug use appear to eclipse the gender-related role-pattern. On the basis of our background data, as well as our therapeutic experience, we postulate that for an individual whose sex-role identity is threatened, drug abuse has a stabilizing function, and it carries a message.

[Economic evaluation in a trial of medically controlled prescription of narcotics to dependent users (PROVE)]. / Gesundheitsökonomische Bewertung der Versuche für eine ärztliche Verschreibung von Betäubungsmitteln (PROVE).

In the 1994-1996 trial of medically controlled prescription of narcotics to dependent users, 800 places were ascribed to heroin substitutes and another 200 for methadone and morphine substitutes. The trial was evaluated with the aid of an accompanying research. Among the results demonstrated in the evaluation was an improvement of the health of the participants. The economic assessment was drawn from observations of health effects within a sub-sample of 142 participants from four centers. In a retrospective statistical survey, for each acute illness which could be influenced through the trial, the number of diagnoses was recorded in the first and thirteenth month after study entry. Also, based on a number of representative cases for each of these acute illnesses, the resource use, i.e. the types and numbers of medical products and services rendered to the patients, was recorded. The results showed a clear decline in depressive episodes, skin diseases, digestive system disorders as well as epileptic attacks and intoxication. Treatment costs could be reduced from a total of CHF 94875.--to CHF 21,998.--/month or from CHF 22.27 to CHF 5.15/patient per day. The improvement of somatic and psychic health due to the medically controlled prescription of narcotics resulted in a benefit of CHF 17.11/person per day.

The Zurich Study--a prospective epidemiological study of depressive, neurotic and psychosomatic syndromes. IV. Recurrent and nonrecurrent brief depression.

How common and how significant are brief depressive episodes (BDE) lasting less than 2 weeks? The authors propose splitting the BDE into two groups: one occurring monthly over 1 year of observation, termed 'recurrent brief depression' (RBD), and those occurring less frequently, labeled 'nonrecurrent brief depression' (NRBD). From a medical point of view, the RBD are a relevant group. Different thresholds of definition are tested, the narrowest of which (including occupational impairment and predetermined minimum number of symptoms) is accepted for 'case'-definition. The such defined RBD (SYM) group differs from major depression only by length and frequency of episodes. In a young cohort, its 1-year prevalence rate was found to be 4.4% (males 3.9%, females 4.9%). One-third of these cases needed treatment, a fourth suffered from pronounced subjective and social impairment as well as from persistent suicidal ideation. The self-reporting of subjective impairment, assessed with the SCL-90 symptom inventory and an analog-rating, yields high scores which are in no way inferior to major depression diagnosed with RDC, DSM-III or EDE (SYM) criteria. The RBD (SYM) demonstrate less hypomania than the major depressive disorders. On the other hand, a family history of depression is equally frequent across all groups. The validity of the RBD (SYM) group has yet to be confirmed by a follow-up study, and further research is needed to delineate it from secondary depression. The findings largely support the hypothesis of a continuum from mild and short to more severe, longer lasting depressive syndromes, but they do not exclude heterogeneity of RBD (Angst and Dobler-Mikola 1984b).(ABSTRACT TRUNCATED AT 250 WORDS)

The Zurich Study. VI. A continuum from depression to anxiety disorders?

A representative sample of 456 persons from the normal population aged 22 and 23 years was used to study the overlap of depression with anxiety disorders. The 1-year prevalence rate for major depression (DSM-III), minor depression, and anxiety disorder together was 16.4%. The observed cases of major depression occurred in 36% with anxiety disorder, the cases with minor depression in 60%. On the level of symptoms assessed by a semistructured clinical interview and on the level of self-assessed items of the symptom check list SCL-90, the overlap was even greater. The main finding was that subjects with both diagnoses, depression and anxiety disorder, were more severely affected in general. Discriminant analyses of the SCL-90 scales together with the qualitative distribution of SCL items characterizing depression, anxiety, or phobia, did not disprove the hypothesis of a continuum.

The Zurich Study. V. Anxiety and phobia in young adults.

From data collected within the frame of a longitudinal epidemiologic study of a representative sample population of young adults (the Zurich Study), anxiety disorders--anxiety and phobic states--were analyzed. The current prevalence rate was found to be 2.9% for anxiety states and 4.3% for phobic states, totaling 7.2%. Because of their anxiety disorders, one-fifth of the cases had undergone treatment during the preceding 12 months. Substantial difficulties arose, from the point of view of classification. The currently used categories, such as anxiety states, panic attacks, agoraphobia, simple phobia, social phobia, have more in common than differing symptoms. On a syndromal level, numerous overlapping configurations resulted which can only be artificially forced into the aforementioned diagnostic classes of anxiety disorders. On the symptom level, merely a few operationalized items defined these categories. In this way, most of a broad identical 'nonspecific' symptomatology was not taken into account. This was exemplified by a comparison of anxiety states and agoraphobia. In fact, these two groups did not differ significantly in many symptoms or in SCL-90 profiles, but did show a highly significant difference from control samples. Both groups suffered to the same great degree from depressive, cardiovascular, and gastrointestinal symptoms. We doubt whether any forced categorical diagnostic differentiation of anxiety and phobic states is at all reasonable.

The Zurich study. II. The continuum from normal to pathological depressive mood swings.

The longitudinal study of a cohort of 591 men and women aged 20 and 21 years respectively at outset, and 23/24 years at a subsequent investigation, was analyzed for the manifestation of depressive syndromes. The syndromes were grouped according to their duration: 1 week once or twice per year (group B), 1 week three or more times per year (C), 2 weeks (D), 4 weeks (E) and 3 months (F). Prevalence rates are given over 1 month, 3 months and 1 year, subdivided by sex. Unexpected identical prevalence rates are found for both sexes up to 3 months. Over 1 year, the ratio shifts to favor the women. Setting out from the hypothesis of a continuum of depressive mood from normal to pathological, groups B to E were examined with respect to the prevailing symptomatology (assessed with an interview and a self-rating questionnaire, the SCL-90R). We found no relevant qualitative differences, only a trend of somatic symptoms becoming more prominent along with increasing duration of episode. Symptomatology thus does not point to further classification. Other criteria, such as subjective impairment, social impairment, illness behavior, discussing depressive mood with parents/friends/employer, treatment, all favor the assumption of a continuum of depressive syndromes from normal to pathological.

The Zurich study. III. Diagnosis of depression.

A 23- to 24-year-old age group representative of the general population of the Canton of Zurich, was used to detect depression. The classifications obtained by means of the Feighner, RDC and DSM-III criteria are compared with our own concept, which differs in some aspects. A minimum of 2 weeks of depression is labeled as EDE (extensive depressive episode). Instead of the presence of a minimum number of depressive symptoms, social impairment at work is first examined as a case-defining criterion (EDE[WORK]); in a second step, a diagnostic threshold of three, and five, depressive symptoms for males and females respectively is adopted (EDE[SYM]). The consequences are presented relating to prevalence, incidence, sex distribution, overlap with other diagnostic concepts, severity, bipolarity and family history. An unequal sex distribution in depression is shown to be an artifact of definition. Preference should go to a case-definition that could be specifically adapted to a given problem. On the whole, the DSM-III and EDE(WORK) criteria appear to be too broad. We will henceforth prefer the RDC and EDE(SYM) criteria, which both, however, necessitate further methodological and empirical study.

Capillary density of tenotomized skeletal muscles. I. Experimental study in the rat.

Our purpose was to study the capillary density of rat gastrocnemius muscle by microangiography 7-21 days after achillotenotomy or immobilization in a plaster cast. Sixteen animals were tenotomized, 12 immobilized in a plaster cast, and 4 served as controls. The number of capillaries was counted per 1,000 muscle fibres from each sample. No site differences were found in control muscles, where on an average 1,250 capillaries per 1,000 muscle fibers were found. After tenotomy the number of capillaries was decreased 35%, 31%, and 32% on days 7, 14, and 21, respectively. In immobilized muscles the decrease in capillary density occurred slowly, the corresponding decrease being 23%, 33%, and 28% on days 7, 14, and 21, respectively. These results indicate that the capillary density of muscular tissue is greatly decreased following the disuse produced by tenotomy or immobilization.

The Zurich Study. VII. Insomnia: symptoms, classification and prevalence.

This study describes sleep behaviour and insomnia in a representative cohort of a Swiss population. Interviews were carried out prospectively from age 20-21 to 27-28 years, starting with 292 males and 299 females. Females usually go to bed earlier and sleep 30 min longer than males. Taking into account length and periodicity of insomnia we can distinguish occasional insomnia (OI), repeated brief insomnia (RBI), and continued insomnia (CI), defined by operational criteria. The prevalence of sleep problems is stable from age 21-28, at 36%-40%. CI (prevalence 8%-10%) and RBI (13%-19%) are both medical problems in terms of treatment by professionals (10%-17%) or self-medication (7%-12%). The majority of insomniacs cope with sleep problems in various other ways. Frequency and patterns of symptoms of insomnia are described.

Prescribing narcotics to drug-dependent people in prison: some preliminary results.

AIDS: Switzerland began testing a program in which narcotics are prescribed under medical care for drug-dependent inmates. The goal of the program being run at the Oberschongrun penitentiary is to make drug-dependent people feel better, have the chance of becoming stable in prison, and escape the vicious cycle of committing further drug-related crimes when they are released. Participation in the trial is voluntary. Participants must be at least 20 years of age, been drug dependent for two years, and have undergone unsuccessful drug treatment. An additional selection criterion is illegal consumption of heroin while incarcerated. Issues involved with the trial are described, including the conflicts inherent in prescribing drugs that are usually considered illegal. Preliminary conclusions show that the program is feasible, although there are significant problems in instituting this type of program in an environment that is totalitarian and rigid. The program raises prison role issues of rehabilitation versus punishment.^ieng