Estimation of surface area and volume of a nematode from morphometric data

Nematode volume and surface area are usually based on the inappropriate assumption that the animal is cylindrical. While nematodes are approximately circular in cross section, the radius varies longitudinally. We use standard morphometric data to obtain improved estimates of volume and surface area based on (i) a geometrical approach and (ii) a Bezier representation of the nematode. These new estimators require only the morphometric data available from Cobb's ratios, but if fewer coordinates are available the geometric approach reduces to the standard estimates. Consequently, these new estimators are better than the standard alternatives

The spurious correlation between concentration and creatinine-corrected concentration in urine

The use of urinary analytes to monitor physiological processes relies on making the correct measurement. Three alternatives are commonly contemplated: concentration, creatinine-corrected concentration and excretion rate. Of these, the latter is the most reliable, but is perceived by some to be difficult to measure. This has led to the more frequent reliance on concentration and one of the justifications for this is the reported linear relationship between the concentration and the creatinine-corrected concentration. We show that this correlation is spurious in that the magnitude of the correlation coefficient depends on the ratio of the standard deviations of the creatinine and analyte concentrations. As an example urinary analyte we use pregnanediol (Pd) which is an important tool for women wishing to monitor their own fertility. Urinary Pd concentration is not a reliable substitute for creatinine-corrected Pd concentration or the Pd excretion rate

Estimation of Surface Area and Volume of a Nematode from Morphometric Data

Nematode volume and surface area are usually based on the inappropriate assumption that the animal is cylindrical. While nematodes are approximately circular in cross section, the radius varies longitudinally. We use standard morphometric data to obtain improved estimates of volume and surface area based on (i) a geometrical approach and (ii) a Bézier representation of the nematode. These new estimators require only the morphometric data available from Cobb's ratios, but if fewer coordinates are available the geometric approach reduces to the standard estimates. Consequently, these new estimators are better than the standard alternatives

Distinguishing a ‘hit’ from a ‘view’: Using the access durations of lecture recordings to tell whether learning might have happened

Audiovisual recordings of lectures are available to many students in all disciplines. The use of lecture recordings has been studied extensively, but it is still not clear how, or how much, they are actually used. Previous analysis of their use has been based on either survey data or computer logs of access. In the latter case, measurements of actual use have usually been based on counts of the number of times recordings have been accessed. This does not distinguish those that happen accidentally (‘hits’), from those that might permit learning (‘views’). This distinction is essential to the meaningful analysis of the log of the actual use of recorded lectures. Using the access logs of undergraduate science students, we show that the distribution of the durations of the access of recordings of scheduled lectures has two distinct components. The most rapid of these is complete within three minutes and we infer that it reflects the behaviour of students searching among recordings. This inference is based on a comparison of these distributions with those of (i) recordings made automatically during a non-teaching period and (ii) individual users. This is also consistent with the pattern of usage by students searching for a specific recording

Multiple novel prostate cancer susceptibility signals identified by fine-mapping of known risk loci among Europeans

Genome-wide association studies (GWAS) have identified numerous common prostate cancer (PrCa) susceptibility loci. We have fine-mapped 64 GWAS regions known at the conclusion of the iCOGS study using large-scale genotyping and imputation in 25 723 PrCa cases and 26 274 controls of European ancestry. We detected evidence for multiple independent signals at 16 regions, 12 of which contained additional newly identified significant associations. A single signal comprising a spectrum of correlated variation was observed at 39 regions; 35 of which are now described by a novel more significantly associated lead SNP, while the originally reported variant remained as the lead SNP only in 4 regions. We also confirmed two association signals in Europeans that had been previously reported only in East-Asian GWAS. Based on statistical evidence and linkage disequilibrium (LD) structure, we have curated and narrowed down the list of the most likely candidate causal variants for each region. Functional annotation using data from ENCODE filtered for PrCa cell lines and eQTL analysis demonstrated significant enrichment for overlap with bio-features within this set. By incorporating the novel risk variants identified here alongside the refined data for existing association signals, we estimate that these loci now explain ∼38.9% of the familial relative risk of PrCa, an 8.9% improvement over the previously reported GWAS tag SNPs. This suggests that a significant fraction of the heritability of PrCa may have been hidden during the discovery phase of GWAS, in particular due to the presence of multiple independent signals within the same regio

Pathological chemotherapy response score is prognostic in tubo-ovarian high-grade serous carcinoma: A systematic review and meta-analysis of individual patient data

There is a need to develop and validate biomarkers for treatment response and survival in tubo-ovarian high-grade serous carcinoma (HGSC). The chemotherapy response score (CRS) stratifies patients into complete/near-complete (CRS3), partial (CRS2), and no/minimal (CRS1) response after neoadjuvant chemotherapy (NACT). Our aim was to review current evidence to determine whether the CRS is prognostic in women with tubo-ovarian HGSC treated with NACT.This article is freely available via Open Access. Click on the Publisher URL to access the full-text via the publisher's site

The livestock burdent of parasitism database: a strategic management tool

The parasite burden of livestock places an enormous burden on both the animals and farmer. Parasite control usually involves the use of anthelmintics to which the parasites are rapidly developing resistance. To prolong the usefulness of the current generation of anthelmintics it is prudent to monitor their use and effectiveness, and provide reliable advice to farmers and veterinarians in order to minimise their use. We describe the prototype of the Livestock Burden of Parasitism database that is based on a Java interface to R which generates the web pages and graphics needed to respond to the requests of a user. The database is accessible at various levels according to the needs of the user and allows the input and checking of new data as well as the output of appropriate summaries of existing data. The database provides a tool for the management of anthelmintic use, the identification of successful treatment strategies and the provision of advice

Graphical spreadsheet tools for learning enzyme kinetics

Many students lack sufficient mathematical skill or confidence to be able to visualise a process just by looking at an equation. This is particularly apparent when students are working on the dynamics of enzyme action. Understanding the basic concepts of enzyme kinetics is essential to any appreciation of the chemical processes that occur in living organisms. Fortunately, learning can be enhanced by direct manipulation of the parameters while students observe the behaviour of the graphs of the functions. Spreadsheets are described that enable students to analyse the significance of the parameters at several levels, to connect concepts between levels of treatment and to use the basic expression in the analysis of their own experiments. Methods for constructing these spreadsheets in Excel and the essentials of the relevant theory are also summarised