bluuebunny/crossref_metadata_2025_split huggingface dataset:
Branchial Ventilation in the Burrowing Crab,Atelecyclus Rotundatus
Authors: Taylor A. C. 
Published: May 2009

Atelecyclusburies itself by digging backwards into the sand, sometimes until only the antennae protrude above the sand. In this position it is difficult for the animal to maintain an adequate respiratory current through the branchial chambers by pumping water in the normal direction.Studies of the ventilatory behaviour ofAtelecyclushave shown that, when on the surface of the sand, water flows through the branchial chambers as in most other crabs i.e. water enters the chambers at the base of the limbs and the exhalant water leaves anteriorly. This direction of flow is also maintained when the crabs are only partially buried but when more deeply buried, the direction of water flow is reversed by the reversal of the direction of beat of the scaphognathites and water is drawn down the antennal tube and leaves the branchial chambers at the base of the limbs.InactiveAtelecyclusshow a well-defined rhythm of pumping in which regular periods of active pumping alternate with periods during which the scaphognathites stop beating and ventilation of the branchial chambers ceases. The rhythm of ventilation is regular but the duration of the ventilatory pauses (apnoea) may vary considerably between animals.During pausing, the activity of the scaphognathites and of the heart are closely synchronized. The cessation of scaphognathite activity is accompanied by a period of cardiac arrest, although single heart beats may sometimes occur during a pause.As in many decapods, the Po of the post-branchial blood was high (Pa, o = 92 torr, Pv, O = 21 torr) but during a pause P, o gradually declined.
Factors Controlling Cold Tolerance and Breeding inBalanus Balanoides
Authors: Crisp D. J. , Lewis A. H. 
Published: May 2009

Measurements during autumn and winter of the lower median lethal temperature of the barnacleBalanus balanoides(L.) under natural and modified environmental conditions in field and laboratory, show that the cold resistant state is advanced by three factors: short day photoperiod, reduced food assimilation and reduced temperature. Their relative efficacy is in that order.These factors combine in promoting breeding and the acquisition of the cold tolerant state during autumn and winter. Although normally associated, breeding and cold tolerance are not mutually dependent; the one can be induced without the other under abnormal conditions.Similar measurements made in the spring show that only a single factor is required to terminate the cold tolerant state — resumption of food assimilation. If feeding is discontinued in the spring, however, the cold tolerant state tends to return, but animals that have bred do not breed again until the following autumn.Of the three well established mechanisms for seasonal cold tolerance — production of substances to cause freezing hysteresis, production of cryoprotective agents, and nucleating agents to promote freezing in the intercellular compartment — only the last can be entertained since the cold tolerant animal survives some 80% of the body fluids being converted to ice. The cold tolerant condition may also relate to higher levels of polyunsaturated fatty acids being present in the membrane lipid fraction in winter, so rendering cell membranes less prone to damage by ice crystals.The suggestion is made that normal metabolic activity and tolerance of low chemical potential of water - the common factor in freezing and desiccation - are not compatible.
The Benthos of a Marine Fly-Ash Dumping Ground
Authors: Bamber Roger N. 
Published: May 2009

AbstractThe benthic fauna of a fly-ash dumping ground off the Northumberland coast has been studied in comparison with that of the surrounding natural sediments and a designated offshore spoil ground. Continued ash dumping has resulted in an increase in the silt fraction of the sediments, together with the appearance of pozzolanic aggregates at the sites of greatest dumping, some 3·5 km offshore. The sediments here show a more rapid decline in Eh values with depth. The natural benthic macrofauna represented a typical Echinocardium-filiformis community, giving way throughout the offshore spoil ground to a ‘ Paraonis-Magelona’ community dominated by smaller polychaete species more tolerant of poor sediments, while the stations at the centre of the ash dumping showed an anomalous community structure. The density of the fauna was reduced at the centre of the ash dumping, the worst station yielding only eight individuals in 0·2m. Contours of numbers of macrofaunal individuals and species, of faunistic diversity and biomass, and of meiofaunal numbers all show a similar pattern of some depression along the spoil ground, and greater depression at the ash-dumping centre. Statistical analyses confirm a significant negative correlation between faunistic parameters and ash content. Deposit-feeding species represented a lower proportion of the community at sites of high ash content. The negative correlation between faunistic diversity and ash content was statistically significant over an area of 43 km around the centre of the dumping. The faunistic impoverishment is considered mainly to be a response to the dumping per se, and options for reducing this effect are discussed.
Calcification in the Shore Crab,Carcinus Maenas(L.): pH and the Precipitation of Carbonate From Sea Water and Blood
Authors: Digby Peter S. B. 
Published: May 2009

Much evidence has suggested that calcification inCarcinusand certain other marine organisms may arise at least partly by the local formation of base. The extent of changes of pH needed to precipitate calcium carbonate from sea water or from the blood of the crab are not known with certainty. These have been investigated, using sea water and crabs from the coast of Maine.Mean sea water pH, mostly as measured in aerated samples used for experiments in the laboratory, was 8·00, a little below the values commonly found close to the shore in summer. The corresponding mean blood pH was 7·12. Crushing calcified crab cuticle in sea-water raised the pH, showing the sea water to be below saturation with the salts concerned. The rise in pH was slightly greater in the more dilute suspensions, an effect attributed to the mixed composition of the calcifying salts. Thus in one group of experiments cuticle crushed in sea water in proportions 1:20 and 112·7 raised its pH by 0·66 and 0·62 units respectively, and extrapolation suggested that interstitial fluid of almost zero volume would equilibrate at 0·38 pH units above sea water. Crushing cuticle in crab blood in proportion 1:2·7 raised its pH by 1·03 units, showing the plasma also to be unsaturated with carbonate.Carbonates were precipitated from sea water by rendering it alkaline with sodium hydroxide; in four experiments the first crystallites were found in samples in which in 3 days after addition of base pH had fallen to between 8·46 and 9·30. In a longer series of experiments with crab plasma, crystals were first seen in samples in which after three days the mean pH had fallen to 8–09. Crystallites at the surface formed mosaics of spherulites closely resembling those of normal crab cuticle.
The Food of Post-Larval Fish. No. II (1918)
Authors: Lebour Marie V. 
Published: May 2009

Investigation of the food of larval and post-larval fish from the townets has been continued throughout the year (1918) in the same way as previously, by examining the contents of stomach and intestine in the fresh state. From May 24th a new big net made of stramin, with a wooden frame 36 inches by 25 inches, was used in addition to the ordinary tow-nets. Any live specimens, and these were chiefly caught in the big net, were kept in small aërated aquaria standing in running water and fed with plankton in order to see, when possible, what food they ate. In this way a few post-larval fish went through the metamorphosis into the adult form. Details of these will be found in another paper in the same number of the Journal (page 9).The tow-nettings were regularly examined by Miss Webb in order to see whether the fish were feeding on what was commonest at the moment, and this was found to be usually the case, so far as the Copepods were concerned, although most of the young fish seemed to select their food to a certain extent. In any month the Copepods which are at that time commonest in the plankton are those most eaten by the young fish, but most of them have preferences and select in various degrees.
Thus in June Calanus finmarchicus and Acartia clausi were the commonest Copepods, Temora longicornis coming next, Pseudocalanus elongatus and Oithona similis not occurring so frequently. The commonest young fish in the tow-nets in the same month were the Whiting, Pollack, Rockling and Ballan Wrasse (Labrus bergylta).
Biometrics, Carbon and Nitrogen Content in the Ophiuroid Ophiothrix Fragilis
Authors: Davoult D. , Degros N. , Janquín M. A. , Soyez B. 
Published: May 2009

Relationships between size, wet weight, dry weight, carbon and nitrogen content were determined in Ophiothrix fragilis (Echinodermata: Ophiuroidea). Such relationships appeared very useful when studying dynamic processes such as nutrition, growth, excretion or reproduction, considered as fluxes of carbon and nitrogen in the ecosystem.Relationships between size, wet weight, dry weight, ash free dry weight, carbon and nitrogen content of organisms are of fundamental interest in ecological studies of ecosystems. They allow us to understand and quantify the role of a species as it stores, consumes or produces organic matter during its life cycle. Determination of conversion factors are time-consuming but very useful for estimating flows in the ecosystem (Brey et al., 1988). Some compilations of conversion factors have been published (Båmstedt, 1981; Rumohr et al., 1987).Ophiothrix fragilis (Abildgaard) is the dominant species of the ‘pebbles with sessile epifaunal community’ (Davoult, 1990), located in the Dover Strait (eastern Channel), where tidal currents are very strong. It is considered as an efficient suspension feeder (Roushdy & Hansen, 1960; Warner, 1971) and lives in dense populations (1000–2000 individuals m-2; Davoult, 1989) which are assumed to have a significant effect on the fluxes of organic matter from the pelagic to the benthic system and on the fluxes of ammonium to the water column (Davoult et al., 1991).Individuals were sampled in May and June 1991 off the Cape Gris-Nez (50°55′N 1°35′E). Two-hundred individuals were measured (diameter ±01 mm, after Guille, 1964), dried at 60°C for 48 h, weighed (±0·1 mg), burnt at 520°C for 6 h (Anonymous, 1986), and the ash weighed (±0·1 mg). Total organic carbon and nitrogen content were determined with a CHN element analyser (Carlo Erba 1106): after a flash combustion in a helium stream temporarily enriched with pure oxygen, quantitative combustion was achieved by passing gases over Cr2O3 after a transfer through a reduction reactor to eliminate the excess of oxygen; components were separated in a chromato-graphic column, eluted, then measured by a thermal conductivity detector. Thirty-eight dried ophiuroids were ground with a micro-grinder, then two sub-samples (except for individuals <2 mm) were weighed at ±1 μg (76 measurements).
The Reproductive Maturity of the Common Eel
Authors: Cunningham J. T. 
Published: May 2009

In the Museum of the Royal College of Surgeons, in London, there are two specimens of the common eel, in which the ovaries are much enlarged, greatly distending the abdomen, and evidently very nearly ripe. Both those specimens were presented by Mr. Geo. Buckeridge, a salesman in Billingsgate Market, who deals largely in eels. The following are certain particulars concerning the specimens:—(1) Length 15 in., weight 4½ oz. Presented Jan. 4, 1894.(2) Length 19 in., girth round the abdomen 5½in., weight 10¼ oz. Presented Sept. 25, 1895.
Report on the Sponge Fishery of Florida and the Artificial culture of Sponges
Authors: Allen E. J. 
Published: May 2009

SUMMARYI. The Florida Sponge Fishery .—History of the Fishery. Kinds of sponges taken. Relative value of sponges. Methods of procuring sponges. Curing the sponges. Sponge grounds reduced in value through over—fishing.Sponge Culture Experiments.—historical.Experiments of Buccicli. —Description of apparatus used, and manner in which the experiments were conducted. Buccich concluded that sponge cuttings would grow to marketable size in seven years.Experiments in Florida.—Sponge cuttings said to grow more rapidly, increasing to from four to six times their original size in six months, when placed under favourable conditions.Memorandum by Mr. Benedict, of U.S. National Museum,.—Sponge culture experiments do not appear to have been tried to any great extent. Fishermen opposed to anything of the kind as likely to lead to monopoly, and the cutting off their means of subsistence.Would Sponge—Culture By Cuttings Be Profitable—Marenzeller points out that this would depend on whether pieces of a sponge would in a given time together attain a greater weight than the original sponge would have reached if left undisturbed.Suggested Experiments.—Suggestions by Mr. Bidder {see below). Fishing by means of divers, or dredging, should be tried in deeper water.
Ammonium-Limited Continuous Culures of Skeletonema Costatum in Steady and Transitional State: Experimental Results and Model Simulations
Authors: Maske Helmut 
Published: May 2009

The physiological response of ammonium-limited continuous cultures of Skeletonema costatum (Grev.)Cleve to steady-state and transient conditions was tested and compared to simulations with a Droop-type quota model and a four-state variable model (internal amino acid pool added to the quota model). External ammonium, free internal amino acids, protein, silicate and culture-cell volume were measured.All cultures showed reproducible changes in growth and uptake kinetics due to spontaneous cell-cycle synchronization of the populations. Under steady-state conditions protein decreased with increasinggrowth rate from 82%; cell-nitrogen to 52% and free internal amino acids increased from 2·5% cell-nitrogen to 8%. Under transient conditions amino acids could reach 25% of cell-nitrogen.A comparison of model and culture results yielded the following information: Both models could simulate steady-state and most transient conditions. The dependence of the quota on steady-state growth rate is not the result of changes in amino acid or protein pool size. The amino acid pool, an intermediary step in the nitrogen assimilation, does not serve to increase the time lag in growth response significantly. The four-state variable model reproduced under most conditions the behaviour of theamino acid pool without the use of feedback control mechanisms on the rate of uptake. The models could simulate a strong increase in growth rate except when it was initiated by impulse dilution of the culture. Then growth response was controlled by epigenetic mechanisms induction of enzyme synthesis). (6) The maximum nutrient uptake rate per culture cell volume of Skeletonema is inversely related to cell size.
‘The Bourgeois Woman and the Half-Naked One’: Or the Indian Nation's Contradictions Personified
Authors: CIOTTI MANUELA 
Published: May 2009

AbstractThis paper explores the interplay between development, identity politics and middle-class aspirations amongst low-caste Chamar women in rural north India. It argues that this interplay has reinvigorated notions of women's domesticity, education and modern conjugality as they emerged in the reforms and ‘modernising’ efforts of sections of Indian society, since the nineteenth century, in their encounter with the colonial ‘civilising mission’. It will show how the long-term effects of this ‘legacy’, through its reconfiguration and appropriation by members from a low caste, have affected a historically marginalised community in their pursuit of middle-class aspirations. In addition to the criticality of Indian women and their gender roles as ‘sites’ where nation and community transformations are symbolically and practically negotiated, scholars of South Asia have also highlighted the separation between historical and anthropological discourses on women. This paper brings these discourses together and addresses this separation by showing that Chamar appropriation of the ‘modernising’ agenda has initiated a dual process. On the one hand, a minority of women have embarked on an embourgeoisement trajectory predicated on education, ‘modern motherhood’ and aspirations to white collar employment, and on the other hand, underprivileged women (with their ‘unfit’ personas) have become increasingly vulnerable to stigmatisation as a result of being in ‘menial labour’. It is further argued that dialectic study of the ‘two [groups of] Chamar women’ will provide an insightful lens through which inner conflicts within low-caste communities in contemporary India may be understood, and suggests that there are contradictory trends concerning women, their development prospects, and their membership within the nation.
On the astrobiological relevance of viruses in extraterrestrial ecosystems
Authors: Jalasvuori Matti , Örmälä Anni-Maria , Bamford Jaana K.H. 
Published: May 2009

AbstractViruses are the dominant form of genetically reproducing entities on Earth. Yet, viruses are mostly neglected in the context of astrobiology due to their non-living nature. In this discussion it is considered whether viruses are likely to be transferred within bacterial endospores to other planetary bodies through lithopanspermia. Interestingly, it seems possible that ecosystems of panspermial origin might yield biospheres in which viruses are absent. The evolutionary pathway of life in these systems might differ significantly from the path observed on Earth. We hypothesize that the difference in the two potential ways for the emergence of life, those being panspermial or local origin, on any certain planet could be clarified by analyzing the diversity of virosphere on the planet. The use of viruses as putative biomarkers is also discussed and studied.
Exposure of children and adolescents to alcohol advertising on Australian metropolitan free‐to‐air television
Authors: Fielder Lynda , Donovan Robert J. , Ouschan Robyn 
Published: May 2009

ABSTRACTAim  This study investigated the exposure of underage youth to alcohol television advertising on metropolitan free‐to‐air television in the five mainland capital city markets of Australia.Design  Exposure levels (target audience rating points; TARPs) were obtained for all alcohol advertisements screened from November 2005 to October 2006 in each capital city market for: children 0–12 years; underage teens 13–17 years; young adults 18–24 years; and mature adults 25+ years. The 30 most exposed advertisements across age groups were then content‐analysed for elements appealing to children and underage youth.Results  In each of the five metropolitan markets, mature adults were most exposed to alcohol advertising. Children were exposed to one‐third the level of mature adults and underage teens to approximately the same level as young adults. However, there was considerable variation in media weight between markets, such that underage teens in two markets had higher advertising TARPs than young adults in other markets.All 30 highest exposed advertisements contained at least one element known to appeal to children and underage youth, with 23 containing two or more such elements. Fifteen of the 30 advertisements featured an animal.Conclusions  The self‐regulation system in Australia does not protect children and youth from exposure to alcohol advertising, much of which contains elements appealing to these groups.
Sexual orientation, substance use behaviors and substance dependence in the United States
Authors: McCabe Sean Esteban , Hughes Tonda L. , Bostwick Wendy B. , West Brady T. , Boyd Carol J. 
Published: May 2009

ABSTRACTAims  To assess past‐year prevalence rates of substance use behaviors and substance dependence across three major dimensions of sexual orientation (identity, attraction and behavior) in a large national sample of adult women and men in the United States.Design  Data were collected from structured diagnostic face‐to‐face interviews using the Alcohol Use Disorder and Associated Disabilities Interview Schedule DSM‐IV version IV (AUDADIS‐IV).Setting  Prevalence estimates were based on data collected from the 2004–2005 (wave 2) National Epidemiologic Survey on Alcohol and Related Conditions (NESARC).Participants  A large national sample of 34 653 adults aged 20 years and older: 52% female, 71% white, 12% Hispanic, 11% African American, 4% Asian and 2% Native American.Findings  Approximately 2% of the population self‐identified as lesbian, gay or bisexual; 4% reported at least one life‐time same‐sex sexual partner and 6% reported same‐sex sexual attraction. Although non‐heterosexual orientation was generally associated with a higher risk of substance use and substance dependence, the majority of sexual minority respondents did not report substance use or meet criteria for DSM‐IV substance dependence. There was considerable variation in substance use outcomes across sexual orientation dimensions; these variations were more pronounced among women than among men.Conclusions  Results support previous research findings of heightened risk of substance use and substance dependence among some sexual minority groups and point to the need for research that examines the reasons for such differences. Results also highlight important gender differences and question previous findings indicating uniformly higher risk for substance dependence among sexual minorities. Risks appear to vary based on gender and how sexual orientation is defined. Findings have implications for more effective prevention and intervention efforts that target subgroups at greatest risk.
Recanting of life‐time inhalant use: how big a problem and what to make of it
Authors: Martino Steven C. , McCaffrey Daniel F. , Klein David J. , Ellickson Phyllis L. 
Published: May 2009

ABSTRACTAims  To establish the prevalence of recanting of life‐time inhalant use, identify correlates of recanting to gain insight to its causes and develop a method for distinguishing recanters who truly are versus are not life‐time users of inhalants.Design and setting  Longitudinal survey data from students in 62 South Dakota middle schools who were participating in a field trial to evaluate a school‐based drug prevention program.Measurements  At grades 7–8, participants reported on their life‐time inhalant use, other drug use and drug‐related beliefs, attitudes and behaviors.Findings  Forty‐nine per cent of students who reported life‐time inhalant use at grade 7 recanted their reports a year later. Comparison of students who recanted inhalant use with those who did or did not report inhalant use consistently on drug‐related beliefs, attitudes and behaviors at grades 7 and 8 suggested that, whereas some inhalant use recanting reflects denial of past behavior, some reflects erroneous initial reporting. Based on a latent mixture model fitted to the multivariate distribution of grade 7 and grade 8 responses of recanters and consistent reporters, we calculated the probability that each recanter was, in fact, a life‐time inhalant user. An estimated 67% of the recanters in our sample appear to be life‐time inhalant users who admitted use in grade 7 and then denied that use at grade 8; 33% appear to be students who reported use incorrectly at grade 7 and then corrected that error at grade 8.Conclusions  Inhalant use recanting is a significant problem that, if not handled carefully, is likely to have a considerable impact on our understanding of the etiology of inhalant use and efforts to prevent it.