Site Specific Relationships between COVID-19 Cases and SARS-CoV-2 Viral Load in Wastewater Treatment Plant Influent

Wastewater based epidemiology (WBE) has become an important tool during the COVID-19 pandemic, however the relationship between SARS-CoV-2 RNA in wastewater treatment plant influent (WWTP) and cases in the community is not well-defined. We report here the development of a national WBE program across 28 WWTPs serving 50% of the population of Scotland, including large conurbations, as well as low-density rural and remote island communities. For each WWTP catchment area, we quantified spatial and temporal relationships between SARS-CoV-2 RNA in wastewater and COVID-19 cases. Daily WWTP SARS-CoV-2 influent viral RNA load, calculated using daily influent flow rates, had the strongest correlation (ρ > 0.9) with COVID-19 cases within a catchment. As the incidence of COVID-19 cases within a community increased, a linear relationship emerged between cases and influent viral RNA load. There were significant differences between WWTPs in their capacity to predict case numbers based on influent viral RNA load, with the limit of detection ranging from 25 cases for larger plants to a single case in smaller plants. SARS-CoV-2 viral RNA load can be used to predict the number of cases detected in the WWTP catchment area, with a clear statistically significant relationship observed above site-specific case thresholds.

The Influence of Logic on Conditional Reasoning Performance

Two experiments are reported, in each of which subjects were asked to decide whether or not a number of statements, including the inverse, converse and contra-positive, followed logically from a given conditional rule of the form “if P then Q”. Rules referred to letter, number relationships, the linguistic form being manipulated by systematic negation of the antecedent and consequent components.

The influence of logical validity on responses was investigated by examining differential frequencies with which inferences were drawn and by testing for consistent behaviour across inferences which depend upon the same logical principle. These analyses revealed little evidence for an influence of logic. Responses were found to be substantially influenced by a response bias, such that subjects showed a preference for agreeing with statements having affirmative antecedents and negative consequents. This finding was in part a replication of parallel findings on other inference tasks. In addition, correlational evidence suggested that subjects’ susceptibility to these biases was consistent across problems.

A possible explanation of the non-logical biases, in terms of a “caution” effect, was proposed and it was argued that these, and other, findings indicate that logical validity plays little role in mediating behaviour regarding the consequent of a conditional rule.

Environmental influences on virus-host interactions in an Australian subtropical reservoir

Viral and prokaryotic interactions in freshwaters have been investigated worldwide but there are few temporal studies in the tropics and none in the sub-tropics. In this 10-month study, we examined temporal changes in virus-host interactions and viral life cycles (lytic versus lysogenic) in relation to the prevailing environmental conditions in a subtropical water reservoir (Wivenhoe) in southeast Queensland, Australia. Heterotrophic prokaryotes and picocyanobacteria were positively correlated with concentrations of viruses throughout the study, indicating the presence of both bacteriophages and cyanophages in the reservoir. The percentage of heterotrophic prokaryotes and picocyanobacteria containing intracellular viruses (FVIC) ranged between 0.2% and 2.4% and did not vary significantly over the 10-month study, whereas lysogenic heterotrophic prokaryotes were only detected in the drier months of June and July. Spearman rank correlation analysis showed that the oxidative-reduction potential (ORP) of the water reservoir influenced the concentrations of viruses, heterotrophic prokaryotes and picocyanobacteria significantly, with low ORP offering a favourable environment for these components. There was a negative relationship between FVIC and rainfall suggesting the associated run-off altered virus-host interactions. Overall, our study provides novel information and inferences on how virus-host interactions in subtropical freshwaters might respond to changes in precipitation predicted to occur with global climate change.

How viruses control microbial ecosystems

Viruses are the most abundant nucleic acid containing biological parcel on earth, being ten times more than bacteria and archaea. Most are phage (infect bacteria), have a genome of DNA or RNA, and are encapsulated in a protein coat at concentrations of 1010/L in aquatic environments. The planet holds 1031 viruses inthe oceans alone and their biomass equals 200 Mt of carbon or 75 million blue whales. Stretched end-to-end they would span 10 million light years. They are obligate parasites and without doubt a pervasive influence on microbial ecosystems.

Sensitive and meaningful measures of bacterial metabolic activity using NADH fluorescence

Successful biological wastewater treatment depends on bacterial metabolic activity. Commercial fluorimeters are designed to monitor this activity using the native fluorescence of Nicotinamide Adenine Dinucleotide [NADH]. However, fluorescence measurements in wastewater treatment plants remain scarce due to difficulties with interpreting fluorescence data. This paper shows that fluorescence probe measurements taken from wastewater do not represent bacterial cell metabolic activity because intracellular NADH is likely swamped by the stable extracellular NADH fraction. Thus, a simple filtration/extraction/centrifugation method was developed to collect the bacterial cells, extract the intracellular NADH using heat treatment in Tris buffer and collect the purified intracellular NADH fraction. NADH standards were used to quantify NADH from the unknown wastewater samples where limits of detection were between 1 nmol mL(-1) and 0.35 micromol mL(-1). Fluorescence of [NADH] greater than 0.35 micromol mL(-1) was self-quenched. At high pH's NADH was stable outside the cell. NADH was stable at neutral and basic pH ranges of pH 7 to 11, but declined proportionally below a pH of 7. Since commercially available fluorescence probes used for measuring NADH are more likely detecting extracellular NADH, separating bacterial cells from water samples followed by NADH extraction was essential to distinguish intracellular and extracellular [NADH]. Here we have proposed three simple steps to meaningful measures of bacterial metabolic activity based on the autofluorescence of NADH. The three simple steps to getting it right are Future development of an on-line monitoring system based on these three steps is achievable with a little ingenuity.

Identification of cyanophage Ma-LBP and infection of the cyanobacterium Microcystis aeruginosa from an Australian subtropical lake by the virus

Viruses can control the structure of bacterial communities in aquatic environments. The aim of this project was to determine if cyanophages (viruses specific to cyanobacteria) could exert a controlling influence on the abundance of the potentially toxic cyanobacterium Microcystis aeruginosa (host). M. aeruginosa was isolated, cultured, and characterized from a subtropical monomictic lake-Lake Baroon, Sunshine Coast, Queensland, Australia. The viral communities in the lake were separated from cyanobacterial grazers by filtration and chloroform washing. The natural lake viral cocktail was incubated with the M. aeruginosa host growing under optimal light and nutrient conditions. The specific growth rate of the host was 0.023 h(-1); generation time, 30.2 h. Within 6 days, the host abundance decreased by 95%. The density of the cyanophage was positively correlated with the rate of M. aeruginosa cell lysis (r(2) = 0.95). The cyanophage replication time was 11.2 h, with an average burst size of 28 viral particles per host cell. However, in 3 weeks, the cultured host community recovered, possibly because the host developed resistance (immunity) to the cyanophage. The multiplicity of infection was determined to be 2,890 virus-like particles/cultured host cell, using an undiluted lake viral population. Transmission electron microscopy showed that two types of virus were likely controlling the host cyanobacterial abundance. Both viruses displayed T7-like morphology and belonged to the Podoviridiae group (short tails) of viruses that we called cyanophage Ma-LBP. In Lake Baroon, the number of the cyanophage Ma-LBP was 5.6 x 10(4) cyanophage x ml(-1), representing 0.23% of the natural viral population of 2.46 x 10(7) x ml(-1). Our results showed that this cyanophage could be a major natural control mechanism of M. aeruginosa abundance in aquatic ecosystems like Lake Baroon. Future studies of potentially toxic cyanobacterial blooms need to consider factors that influence cyanophage attachment, infectivity, and lysis of their host alongside the physical and chemical parameters that drive cyanobacterial growth and production.

Biliary PAH metabolites and EROD activity in flounder (Platichthys flesus) from a contaminated estuarine environment

The present study in the Firth of Forth, Scotland, emphasises the usefulness of biliary metabolite measurements in estuarine monitoring using the flounder (Platichthys flesus). The short time scale (a few hours) of response to polycyclic aromatic hydrocarbon (PAH) exposure, allowed clearer interpretation of trends and differences between sites. Such differences and trends in the metabolite data were not as apparent from 7-ethoxyresorufin O-deethlyation (EROD) activity measurements, which were likely to have been blurred by the movements of flounder between sites. Statistical differences were not observed in EROD activity in flounder from the Firth of Forth (ANOVA, P = 0.065). The biliary metabolites showed statistical differences between the uppermost site of Longannet and Port Edgar, in the outer Firth, for both the 1-OH pyrene and 2-OH naphthalene metabolites (ANOVA, Tukeys, P = 0.012 and 0.022 respectively). There was also a significant correlation between the concentrations of all three individual metabolites (1-OH pyrene, 2-OH naphthalene, I-OH phenanthrene) and the log of the distance downstream from the major PAH input sources of Longannet power station and Grangemouth. Biliary PAH metabolites were shown to better reflect local contamination gradients than EROD activity. This is explained by the relative response times of the two biomarkers and local movements of the flounder in the estuary.

The influence of victim gender and sexual orientation on judgments of the victim in a depicted stranger rape

This study investigated the impact of respondent gender, victim gender, and victim sexual orientation on judgments toward the victim of a depicted stranger rape. Respondents were required to read a scenario in which victim gender and sexual orientation varied between subjects, and to complete measures of behavioral blame, responsibility, and severity of the attack. Results revealed that male respondents made more anti-victim judgments than female respondents did. Male respondents judged gay male victims more negatively than they did other victims. Female respondents' judgments were pro-victim regardless of victim gender and victim sexual orientation. Results are discussed in relation to the feminist analysis of victim blame, and blame toward male rape victims. Implications for support services, particularly of male victims, are also considered.

Managing a complex river catchment: a case study on the River Almond

The River Almond catchment in the east central belt rates amongst Scotland's most polluted rivers. This paper describes how shifting forms of economic development in the catchment since the 1860s have affected river quality. A legacy of effects from past land uses has combined with the impacts associated with current land uses to present a substantial and complex management challenge. It is argued that there have been, and still are, scientific, legislative and socio-economic constraints on the abilities of managers to respond promptly to changing patterns of impacts on the river system. This response lag has tended to increase the costs of subsequent remediation, and has consequently supported a downward pressure on the quality standards that are considered 'realistic' by river managers. Conversely, advances in science, the expansion of regulatory powers and resources, and an increase in public interest in the environment has helped to clarify the extent of the management problems in the catchment, and allowed major advances in some areas of pollution management. In an attempt to overcome some of the remaining weaknesses of river management, river managers and interest groups have started to form inter-sectoral and multidisciplinary partnerships. The success of these new groupings is highly contingent, not so much on the competence of their scientific advice, but on the priority given to water protection by the land-use decision-makers involved, and the resources they are prepared to commit to funding rehabilitation.

Molecular evidence for a common leukaemic progenitor in acute mixed lymphoid and myeloid leukaemia

De novo acute leukaemia presenting with a mixed lymphoid and myeloid leukaemic population has rarely been described. We have used the consensus Ig heavy chain primers and DNA isolated from these two distinct populations of cells in polymerase chain reactions. We demonstrated that both populations of cells exhibited Ig heavy chain gene rearrangements. Cloning and subsequent DNA sequencing of the amplified products showed a common V-D-J junctional nucleotide sequence. This work therefore provides the first evidence that the leukaemic cells in de novo acute leukaemia with a mixed lymphoid and myeloid population are derived from a common progenitor clone and may offer an explanation for the poor prognosis in these patients.

Gide in the U.S.S.R.: some observations on Comradeship

After 1914-18, Gide emphasized the value of the Comradeship of Mankind rather than the essentially individualistic ethos to which he had been previously committed. However, while believing in the social benefits of tolerating pederasty, he still saw a person's difference from the norm as the guarantee of authenticity. Political idealism and curiosity took him to the U.S.S.R. in 1936, and on his return he criticized the inertia, ignorance, and conformism which he considered were encouraged by the Soviet state's promotion of the family unit. This essay examines how his attitude towards sexuality led him to question alleged political freedoms and to see in the Soviet oppression of minorities, including homosexuals, the denial of the revolutionary spirit.

Judgements about victims and attackers in depicted rapes: a review

This paper reviews the effects on subjects' judgements of a variety of factors that have been included in experimental depictions of rape. The focus is on attribution of responsibility or fault to the victim or attacker and related judgements, particularly regarding guilt and sanctions. Generally, females make more pro-victim judgements than do males, and people with non-traditional sex-role attitudes make more pro-victim judgements than do holders of more traditional views. Other factors covered are various victim characteristics, victim-attacker acquaintance, resistance, and victim attire and a range of behaviours prior to the attack. These are limits to generalization due to populations studied and methods used, and the observed effects of several factors are either minimal or inconsistent. However, some factors have reliable effects on judgements, which it is argued are explainable in terms of their link with traditional beliefs about women's rights and roles. Males have often been found to be more susceptible to these effects. In particular, it appears that if a female engages in any behaviour deemed to be 'incautious' that results in victimization then she may be perceived to be at fault, even though these behaviours would be 'legitimate' for males, and that prior romantic involvement with the attacker mitigates the perceived seriousness of, and may even be seen as supplying justification for, a sexual attack. The existence of these attitudes implies that rape may be tacitly condoned in many situations.

The source of belief bias effects in syllogistic reasoning

In studies of the belief bias effect in syllogistic reasoning, an interaction between logical validity and the believability of the conclusion has been found; in essence, logic has a larger effect on unbelievable than on believable conclusions. Two main explanations have been proposed for this finding. The selective scrutiny account claims that people focus on the conclusion and only engage in logical processing if this is found to be unbelievable; while the misinterpreted necessity account claims that subjects misunderstand what is meant by logical necessity and respond on the basis of believability when indeterminate syllogisms are presented. Experiments 1 and 2 compared the predictions of these two theories by examining whether the interaction would disappear if only determinate syllogisms were used. It did, thus providing strong support for the misinterpreted necessity explanation. However, the results are also consistent with a version of the mental models theory, and so Experiment 3 was carried out to compare these two explanations. The mental models theory received strong support, as it did also in the follow-up Experiments 4 and 5. It is concluded that people try to construct a mental model of the premises but, if there is a believable conclusion consistent with the first model they produce, then they fail to construct alternative models.

The effect of set size on the interpretation of quantifiers used in rating scales

Two studies are reported which investigated how people interpret quantifiers of amount such as are commonly used in questionnaires and rating scales. The results indicated that the interpretation of certain quantifiers and rating scales. The results indicated that the interpretation of certain quantifiers varied depending on the context in which they occurred. Low-magnitude quantifiers (e g, 'few', 'several') seemed to signify a much greater proportion when they described small set sizes than when they described relatively large ones. This means that it will be virtually impossible to find quantifiers for use in rating scales which achieve the desirable property of interval scaling. Despite this, some quantifiers are clearly more consistent in their interpretation and more appropriate to use than others, and recommendations are made as to the best ones to use in different situations.

The effect of secoverine hydrochloride on stimulated sigmoid motility: a double-blind, placebo controlled cross-over study in irritable bowel syndrome

The effect of oral secoverine hydrochloride on neostigmine-stimulated sigmoid motility in 12 patients with irritable bowel syndrome was studied in a double-blind placebo-controlled cross-over study. Both spontaneous and stimulated motor activity were significantly reduced by the compound in comparison with placebo. The most sensitive indices were the frequency of wave activity, maximum amplitude and motility index. Two patients reported mild dizziness after secoverine.

Menopausal flushing: double-blind trial of a non-hormonal medication

A multicentre, placebo-controlled, double-blind, cross-over study conducted in general practice on 100 patients has shown clonidine to have a statistically highly significant effect in controlling the number and the severity and duration of menopausal flushes. The relatively mild side effects and the absence of potentially harmful oestrogenic effects suggest that clonidine in the dose range 25 to 75 mug twice daily is a useful addition or alternative to the existing therapy for this common symptom of the menopause.

Controlled trial of dipotassium clorazepate ("Tranxene") in anxiety

Dipotassium clorazepate is a new benzodiazepine derivative with pharmacological and clinical properties resembling diazepam. This report concerns a double-blind placebo-controlled crossover comparison of clorazepate and diazepam which was carried out simultaneously at four centres in the United Kingdom.

Evaluation of Acid Treatments from Pressure Build-Up Analysis

Published in Petroleum Transactions, AIME, Volume 216, 1959, pages 38–43.

Abstract

A method has been developed for evaluating acid treatments in fractured limestone fields by breaking down pressure drawdown into three component parts:pressure differential across "skin" near the borehole face,pressure differential due to flow resistance in the coarse communicating fissures andpressure differential between the fine voids and the coarse fissures.

It is apparent that in most successful acid treatments the first term, skin resistance, has been reduced or eliminated. Further, it is often possible to estimate the volume of coarse fissures associated with the second term, coarse fissure flow resistance. In cases where this volume is comparable with practical acid volumes it seems likely that this resistance also may be attacked with a suitably retarded acid.

Introduction

Acid treatment has been successfully applied as a general practice in the limestone wells in the Mara/ Maracaibo districts of Venezuela for some 10 years. At the same time the need has been felt for a more precise method of:evaluating the effect of an acid job andselecting wells which should benefit from an acid treatment.

The following method, based on an analysis Of build-up curves for wells producing from fractured limestone, provides a means of forecasting the effect acid will have on a well and in many cases the probable order of production rate increase which may be expected. In certain cases it is also possible to calculate the fissure volume through which the acid has to be displaced for best results.

Various approximations are introduced in the method, but within the limitations of these the analysis gives an indication of how a well, whether previously acidized or not, may be expected to respond to acid treatment.