Application of air photograph to porphyry copper exploration

Imperial Users onl

The pre-WDVV ring of physics and its topology

We show how a simplicial complex arising from the WDVV (Witten-Dijkgraaf-Verlinde-Verlinde) equations of string theory is the Whitehouse complex. Using discrete Morse theory, we give an elementary proof that the Whitehouse complex $\Delta_n$ is homotopy equivalent to a wedge of $(n-2)!$ spheres of dimension $n-4$. We also verify the Cohen-Macaulay property. Additionally, recurrences are given for the face enumeration of the complex and the Hilbert series of the associated pre-WDVV ring.Comment: 13 pages, 4 figures, 2 table

Working Group for the Bay of Biscay and the Iberian Waters Ecoregion (ICES WGBIE) (2-9 May 2109)

The ICES Working Group for the Bay of Biscay and the Iberian Waters Ecoregion (WGBIE) assesses the status of 23 stocks distributed from ICES Divisions 3.a–4.a though to Subarea 9, mostly distributed in Subareas 7, 8 and 9. The group was tasked with conducting assessments of stock status for 23 stocks using analytical, forecast methods or trends indicators to provide catch forecasts and a first draft of the ICES advice for 2019. For two of the Nephrops stocks updates were provided on catch data with the advice release delayed until October after the completion of the surveys used for the assessment. Analytical assessments using age-structured models were conducted for the northern stock of white anglerfish, the northern and southern stocks of megrim, four-spot megrim and sole in the Bay of Biscay. The two hake stocks and one southern stock of anglerfish were assessed using models that allow the use of length-structured data (no age data). A surplus-production model, without age or length structure, was used to assess the second southern stock of anglerfish and an age-length structure model was used for the European seabass in the Bay of Biscay. The state of stocks for which no analytical assessment could be performed was inferred from examination of catch, commercial LPUE or CPUE data and from survey information, where available. The northern stock of hake was benchmarked this year to incorporate discards into the model that were previously omitted. New reference points with the accepted benchmark assessment were proposed by the group and new proxy biomass reference points where proposed for black anglerfish in Division’s 7b-k, 8abd. A recurrent issue significantly constrained the group’s ability to fully address the terms of reference this year. Despite an ICES data call with a deadline of six weeks before the meeting, data for most stocks were submitted to ICES only two days before the start of the meeting and in one case 2 days after the meeting commenced. This delayed the process of having the data quality checked and the assessment completed before the start of the working group. This is an important matter of concerns for the working group members. The structure of the report is set out with section 1 presenting a summary of each stock, discussing general issues and conclusions. Section 2 provides descriptions of the relevant fishing fleets and surveys used in the assessment of the stocks. Sections 3–18 contains the single stock assessments

Changes in resuscitation practice at birth

Aim: To investigate secular changes in neonatal resuscitation at birth. Methods: Single centre observational study of 17 890 infants born between May 1993 and April 1997. T-piece ventilation was introduced in April 1995. Observations: Rates and modes of ventilatory resuscitation, early neonatal encephalopathy, neonatal convulsions, and meconium aspiration syndrome; 1 and 5 min Apgar scores; maternal age and method of delivery; paediatric attendance at delivery and resuscitation. Results: The rate of all forms of ventilatory resuscitation fell during the four year period from 11.0% to 8.9%. The rate of intubation fell from 2.4% to 1.2%. A reduced rate of intubation was seen at all gestations of 30 weeks and above. There was no difference in rates of relevant neonatal problems during the period except for a reduction in neonatal convulsions. The introduction of T-piece ventilation did not contribute to the reduction in intubation in a logistic regression model that included time trend. Conclusion: A marked reduction in the rate of intubation was observed, without any reduction in the efficacy of resuscitation. This may reflect improvements and changing emphasis in resuscitation training