Climate Change and Trophic Response of the Antarctic Bottom Fauna

BACKGROUND: As Earth warms, temperate and subpolar marine species will increasingly shift their geographic ranges poleward. The endemic shelf fauna of Antarctica is especially vulnerable to climate-mediated biological invasions because cold temperatures currently exclude the durophagous (shell-breaking) predators that structure shallow-benthic communities elsewhere. METHODOLOGY/PRINCIPAL FINDINGS: We used the Eocene fossil record from Seymour Island, Antarctic Peninsula, to project specifically how global warming will reorganize the nearshore benthos of Antarctica. A long-term cooling trend, which began with a sharp temperature drop approximately 41 Ma (million years ago), eliminated durophagous predators-teleosts (modern bony fish), decapod crustaceans (crabs and lobsters) and almost all neoselachian elasmobranchs (modern sharks and rays)-from Antarctic nearshore waters after the Eocene. Even prior to those extinctions, durophagous predators became less active as coastal sea temperatures declined from 41 Ma to the end of the Eocene, approximately 33.5 Ma. In response, dense populations of suspension-feeding ophiuroids and crinoids abruptly appeared. Dense aggregations of brachiopods transcended the cooling event with no apparent change in predation pressure, nor were there changes in the frequency of shell-drilling predation on venerid bivalves. CONCLUSIONS/SIGNIFICANCE: Rapid warming in the Southern Ocean is now removing the physiological barriers to shell-breaking predators, and crabs are returning to the Antarctic Peninsula. Over the coming decades to centuries, we predict a rapid reversal of the Eocene trends. Increasing predation will reduce or eliminate extant dense populations of suspension-feeding echinoderms from nearshore habitats along the Peninsula while brachiopods will continue to form large populations, and the intensity of shell-drilling predation on infaunal bivalves will not change appreciably. In time the ecological effects of global warming could spread to other portions of the Antarctic coast. The differential responses of faunal components will reduce the endemic character of Antarctic subtidal communities, homogenizing them with nearshore communities at lower latitudes

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Księga poświęcona Profesorowi Hieronimowi Kubiakowi w 75. rocznicę urodzin. Tom ofiarowany przez przyjaciół i uczniów

Membership Functions for Fuzzy Focal Elements

The paper presents a study on data-driven diagnostic rules, which are easy to interpret by human experts. To this end, the Dempster-Shafer theory extended for fuzzy focal elements is used. Premises of the rules (fuzzy focal elements) are provided by membership functions which shapes are changing according to input symptoms. The main aim of the present study is to evaluate common membership function shapes and to introduce a rule elimination algorithm. Proposed methods are first illustrated with the popular Iris data set. Next experiments with five medical benchmark databases are performed. Results of the experiments show that various membership function shapes provide different inference efficiency but the extracted rule sets are close to each other. Thus indications for determining rules with possible heuristic interpretation can be formulated

Reverse osmosis application in the recycling of zinc from the electroplating shop wastewater

The paper reveals the results of the research on the reverse osmosis recovery of zinc from galvanic electroplating. The pilot plant tests were performed in an electroplating shop. Raw washings were concentrated with a spiral wound 2.5x40" module with a composite polymeric membrane. The research tests have proved that the proposed RO process enables successful concentration of the non-ferrous metal in raw washings. The retentate of the RO process has contained about 96% of the metal previously wasted in washings discharged to the environment. The retentate can be recycled to the mother electroplating process. The permeate of the RO process can be recycled to the washing system of the electroplating shop

Reverse osmosis application in the recycling of zinc from the electroplating shop wastewater

The paper reveals the results of the research on the reverse osmosis recovery of zinc from galvanic electroplating. The pilot plant tests were performed in an electroplating shop. Raw washings were concentrated with a spiral wound 2.5x40" module with a composite polymeric membrane. The research tests have proved that the proposed RO process enables successful concentration of the non-ferrous metal in raw washings. The retentate of the RO process has contained about 96% of the metal previously wasted in washings discharged to the environment. The retentate can be recycled to the mother electroplating process. The permeate of the RO process can be recycled to the washing system of the electroplating shop

Photoelectronic measurement methods and the universal measurement system for precise parameter determination of semiconductor structures

In this article a new Multifunctional System for Photoelectric Measurements of Semiconductor Structures (MSPM) is presented. The system enables very accurate photocurrent measurements at levels as low as 10 fA. Measured structures can be biased by sequences of DC voltages and stimulated by light beams of predefined wavelengths and powers. The software controls all the system actions allowing flexibility in retrieving data stored in the related databases