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The potential for pile tip damage and extrusion buckling has become an increasing concern for the offshore wind industry following the trend toward the use of large-diameter thin-walled pile foundations, either as monopiles or as part of a jacket structure. Extrusion buckling may be triggered by an initial pile tip fabrication imperfection or pile damage during transport and handling. It may also be triggered during driving through strong heterogeneous sediments. Numerical analysis of the problem requires advanced and computationally expensive techniques because of the three-dimensional, dynamic and large-deformation nature of the pile and soil deformations. The problem is addressed here by combining coupled Eulerian–Lagrangian simulations with geotechnical centrifuge model test data in dry dense sand. Both approaches consider pre-dented piles with the objective of estimating the soil strength, characterised by the cone resistance, at which minor initial damage will start to propagate. Simplified analysis of structural dent propagation and radial stresses generated in the soil during advance of a deformed pile led to a simple calculation procedure to assess the potential for extrusion buckling. Reasonably good agreement was achieved between the proposed calculation method, numerical simulations and centrifuge tests data, rendering the approach a valuable screening tool for practical application. [ABSTRACT FROM AUTHOR]

The number of incidents worldwide where pile tip damage has occurred during driving has accelerated following the growth of the offshore wind sector, and the expansion into areas with increased risk of embedded boulders or partially weathered soft rocks. The process involving pile–boulder–soil contact can be simulated with advanced three-dimensional (3D) large-deformation dynamic coupled Eulerian–Lagrangian (CEL) finite-element (FE) analysis. However, analyses of this nature are highly time-consuming and computationally expensive. The objective of the paper is to develop a generic framework whereby the potential for denting by a boulder can be assessed a priori. The study encompasses four main components to determine the magnitude of force necessary to create plastic damage of the pile tip and what combination of boulders and soil might generate such reactions during pile installation: (a) a parametric 3D FE structural denting study; (b) a parametric boulder–soil 3D CEL study, where prescribed displacements were applied to the surface of boulders embedded in sand; (c) a range of pile–boulder–soil 3D CEL analyses where a deformable pile and different boulder–soil combinations were simulated; and (d) centrifuge model tests involving tip damage from boulders. Simple relationships and charts have been established from the numerical studies and validated from experimental work. [ABSTRACT FROM AUTHOR]

A field-based experiment was carried out to determine if watercress, commonly harvested by Māori, the indigenous people of New Zealand, could take up the vertebrate pesticide sodium fluoroacetate (Compound 1080), often applied aerially in New Zealand for the control of introduced vertebrate pests. Single toxic baits were placed within seven watercress stands, while three stands received non-toxic controls. Water and plant tissue samples were taken out to 17 days after bait placement, and samples analysed for 1080 content. 1080 was recorded from treatment watercress samples, with a maximum concentration of 63 ppb recorded on Day 7. Subsequent sampling did not show any 1080 in watercress tissue. It is concluded that there is a negligible secondary poisoning risk to humans via consumption of watercress after exposure to 1080.

Injury to the spleen during routine colonoscopy is an extremely rare injury. Diagnosis and management of the injury has evolved with technological advances and experience gained in the management of splenic injuries sustained in trauma. Of the 37 reported cases of colonoscopic splenic injury, 12 had a history of prior surgery or a disease process suggesting the presence of adhesions. Only 6 had noted difficulty during the procedure, and 31 patients experienced pain, shock, or hemoglobin drop as the indication of splenic injury. Since 1989, 21/24 (87.5%) patients have been diagnosed initially using computed tomography or ultrasonography. Overall, only 27.8% have retained their spleens. None have experienced as long a delay as our patient, nor have any had an attempt at percutaneous control of the injury. This report presents an unusual case of a rare complication of colonoscopy and the unsuccessful use of one nonoperative technique, and reviews the experience reported in the world literature, including current day management options.

This paper presents in-stope measurements of total stress and pore-water pressure at strategic locations within three underground stopes at the Raleigh mine site (Western Australia) that were filled with cemented paste backfill (CPB). The three stopes were very similar in shape. Key differences among the stopes were the filling and resting schedules, the barricade drainage systems used, and the cement content of the CPB. Data from the stopes are compared to determine which controllable factors most significantly influence barricade pressures during and after filling. The most significant factor was the scheduling of rest periods between filling, with even very short pauses in filling dramatically reducing the rate of increase of pore-water pressure and total stress with increasing height of fill. Key words: cemented paste backfill, underground mine stopes, drainage, barricade, consolidation, hydration. Le present article presente les mesures de contrainte totale et de pression interstitielle effectuees sur le terrain a differents endroits strategiques, dans trois chambres d'abattage situees dans la mine de Raleigh (Australie-Occidentale) et comblees a l'aide de remblai en pate de ciment. Ces trois chambres avaient des formes similaires. Les principales differences entre les chambres portaient sur la planification des operations de remblayage et des periodes d'attente entre chacune de ces operations, sur les differents systemes de drainage avec murs de confinement utilises et sur la teneur en ciment dans le remblai. On a compare les donnees obtenues pour chaque chambre afin de determiner quels facteurs controlables influaient le plus sur les valeurs de la pression au niveau des murs de confinement, pendant et apres le remblayage. On a constate que le plus important de ces facteurs etait la planification des periodes d'attente entre chaque remblayage et que meme de tres courtes pauses lors du remblayage reduisaient considerablement le taux d'augmentation de la pression interstitielle et de la contrainte totale a mesure que la hauteur du remblai dans les chambres augmentait. [Traduit par la Redaction] Mots-cles : remblai en pate de ciment, chambres d'abattage, drainage, murs de confinement, consolidation, hydratation., Introduction The backfilling of stopes with cemented paste backfill (CPB) is becoming increasingly common at mine sites around the world. With backfill operations consuming up to 25% of total mine [...]

Doherty and Coggeshall combined their two classes--one regular education and one special education--and, agreeing on the value of reader's theater and storyboarding for all students, embarked on a team teaching effort that resulted in improvements for all students, and unprecedented success for "special" students. A template for storyboarding is included. (Contains 2 figures and 1 footnote.)

The summer issue of Midland History features five articles covering various historical periods and topics, including conflict, economic innovations, and health. The issue includes the winning and runner-up essays from the 2023 Midland History Essay Prize, which explored the student community's response to the AIDS epidemic in Britain and the actions of Robert de Ferrers during the Barons Wars in the Midlands. Other articles discuss the collapse of Birmingham's Penny Bank, the industrial endeavors of Emerson Bainbridge, and the muster rolls of the Edgbaston garrison during the first British Civil War. The issue also includes book reviews and welcomes Dr. Ilaria Scaglia to the Midland History Board. [Extracted from the article]