Drum filter performance in a recirculating eel culture unit

The performance of a drum filter of a recirculating eel culture unit was studied. Electron microscopy scanning micrographs of drum filter panels showed a high degree of clogging of the filter mesh (after 4 months of operation). Mean removal efficiency for Total Suspended Solids (TSS) fluctuated considerably between subsequent sampling periods (9.6–18.4%). Drum filtration changed the particle size distribution of fish tank drainage water, resulting in increasing amounts (from 56 to 67% of dry weight, before and after filter passage) of the smaller particle fractions (< 20 μm), thereby indicating a partial breakdown of larger particles during the filtration process. Possible reasons for rapid filter clogging and suggestions for improvements in filter performance are discussed.     

Timing and Factors Affecting Cannibalism in Red Drum, Sciaenops ocellatus, Larvae in Captivity

Since 1987, when the red drum, Sciaenops ocellatus, was introduced into Taiwan, research has been concentrated on its feasibility and biological studies applied to aquaculture. As a part of these biological studies, an experiment was conducted to investigate the timing and factors affecting cannibalism in red drum larvae in captivity. Experimental larvae were graded into small and large sizes. Four treatments were then applied: (1) the control group, (2) water turbidity increased by adding green algae, (3) density of larvae increased twofold, and (4) satiation feeding with Artemia nauplii. Each treatment was triplicated, each in a 12 l test tank stocked with 20 large and 20 small test larvae except those with doubled density of larvae. In a period of three days, the size difference in test larvae was found to be the most important factor affecting cannibalism, whereas water turbidity and density of larvae showed no apparent effect. Satiation feeding significantly decreased but did not stop cannibalism. The peak stage of cannibalism for red drum larvae was likely to occur at a total body length of 1.8–1.9 cm, when the ratio of lower jaw length to total body length was at its maximum.     

Association of Large Juvenile Red Drum, Sciaenops ocellatus, with an Estuarine Creek on the Atlantic Coast of Florida

Seasonal abundance, size distribution, year-class presence, residence duration, and migrational patterns of red drum, Sciaenops ocellatus, in an estuarine marsh creek in the northern Indian River Lagoon, Florida, were investigated during a study in which gill net samples were collected monthly from August 1991 to March 1996. A total of 282 large juvenile red drum were collected, of which 161 were tagged and released and 68 were sacrificed for age determination. Although red drum were collected in the creek throughout the year, abundance levels were negatively correlated with water temperatures and reached maximum levels during the winter months. Significant correlations between fish abundance and salinity or dissolved oxygen levels were not detected. The majority (90%) of the fish collected were large juveniles (260–450mm standard length) that were estimated to be from 10 to 26 months old. The oldest red drum we examined from the creek was estimated to be 37 months old. Tag-recapture data indicated that some fish repeatedly used or were associated with the creek for periods of up to 18 months after release. Estuarine creeks in this region provide exploitable habitat for large juvenile red drum (相似文献   

Selection of Estuarine Nursery Habitats by Wild-caught and Hatchery-reared Juvenile Red Drum in Laboratory Mesocosms

We examined patterns of habitat selection in wild-caught and hatchery-reared early juvenile red drum, Sciaenops ocellatus, using mesocosm experiments. Experiments were performed in the presence and absence of a pinfish, Lagodon rhomboides. We hypothesized that newly recruited red drum would have distinct patterns of habitat selection, and these patterns could be influenced by the presence of a pinfish predator. Red drum were introduced to replicate mesocosms containing all possible pair-wise comparisons of four different habitat types: marsh Spartina alterniflora, non-vegetated bottom/sand, oyster reef Crassostrea virginica, and seagrass Halodule wrightii. Wild-caught and hatchery-reared red drum showed distinctively different patterns of habitat selection. In general, wild-caught red drum selected structured habitats, while hatchery-reared fish did not show strong selection for any habitat type. When a predator was present, wild-caught red drum either changed habitat selection or showed significant selection for other structured habitats. This predator effect was similar albeit weaker for hatchery-reared red drum, but as in the trials without a predator, overall habitat selection was reduced compared to wild-caught red drum. Our results suggest that in the absence of seagrass, other habitat types such as marshes and oyster reefs may be important recruitment habitat for red drum. Additionally, hatchery-dependent behaviors may need to be assessed in designing stock enhancement programs.     

Social Dancing and Incidence of Falls in Older Adults: A Cluster Randomised Controlled Trial

BackgroundThe prevention of falls among older people is a major public health challenge. Exercises that challenge balance are recognized as an efficacious fall prevention strategy. Given that small-scale trials have indicated that diverse dance styles can improve balance and gait of older adults, two of the strongest risk factors for falls in older people, this study aimed to determine whether social dance is effective in i) reducing the number of falls and ii) improving physical and cognitive fall-related risk factors.ConclusionsSocial dancing did not prevent falls or their associated risk factors among these retirement villages'' residents. Modified dance programmes that contain "training elements" to better approximate structured exercise programs, targeted at low and high-risk participants, warrant investigation.

Trial Registration

The Australian New Zealand Clinical Trials Registry ACTRN12612000889853     

Dancing the Main jo'oh: Hma ‘Btsisi’ Celebrate Their Humanity and Religious Identity in a Malaysian World

Official government census takers tick the religion box titled ‘none’ when they fill out the forms for most Orang Asli. Yet at weddings and other festivities, the Hma' Btsisi', an indigenous Mon‐Khmer speaking people of Peninsular Malaysia, perform a religious dance and song cycle called the main jo'oh. Today, in Malaysia, the main jo'oh is a government centrepiece for Orang Asli culture. Btsisi' are frequently asked to perform the main jo'oh for the Malaysian public and for tourists. The main jo'oh is displayed as a curious, albeit beautiful and exotic performance by a heathen people who have ‘no’ religion. But this paper points out that the dance is far from being solely an exotic relic. I argue that the meanings embodied in the dance performance form the foundation of Btsisi' beliefs; in other words, their religion. I conclude by discussing the main jo'oh in the modern Btsisi' and national context. In particular, I demonstrate that the main jo'oh is a way for the Btsisi' to identify and distinguish themselves from other Orang Asli communities as well as from the majority Malay population.     

A histological study of seasonal ovarian development in freshwater drum in the Red Lakes, Minnesota

Female freshwater drum Aplodinotus grunniens Rafinesque, from the Red Lakes of north central Minnesota, U.S.A. were sampled periodically over a 13-month period. Red Lakes drum mature at approximately age 9 and can live to be over 60 years old. The ovarian development of drum from its northern limit of distribution is described histologically. The stages of oocyte growth and the seasonal change in the proportion of oocyte stages within the ovaries are presented. Drum ovaries contained a continuum of oocyte sizes and at spawning, only the largest oocytes are ovulated. A large percentage of the oocytes became atretic mid-way through the spawning season, while gonadosomatic indexes were still high. This may have reduced the spawning potential of Red Lakes drum.     

Genetic characterization of brown meagre (Sciaena umbra) and Shi Drum (Umbrina cirrosa) populations

This study analyzed population structure of fish, brown meagre (Sciaena umbra) and Shi drum (Umbrina cirrosa) from the Black Sea, the Aegean Sea, and the Mediterranean Sea. The Cytb and 16S rRNA genes of Shi drum and brown meagre fish were sequenced. In brown meagre and Shi drum, 25 and 20 haplotypes, respectively, of Cytb gene were identified; while for 16S rRNA, 4 and 8 haplotypes were identified. Nucleotide diversities of 16S rRNA and Cytb gene sites were found to be 83.8% and 52.6%, respectively, for brown meagre; while that for Shi drum were of 80.5% and 73.6%, respectively. There was a significant relationship between geographic distance and the genetic distance of the fish. Since Shi drum and brown meagre are migratory species, they can migrate between the seas. The lack of barriers among different populations facilitates the gene flow among the populations belonging to different regions. Since there is no information available on Shi drum and brown meagre population genetics, this study may be useful to understand the genetic diversity of these species to assist fishery managers for the management of these resources in terms of conservation and sustainability.     

Study on Mechanics of Driving Drum with Superelastic Convexity Surface Covering-Layer Structure

Belt conveyor is one of the main transport equipment in coal mine and the driving drum is its key part. With the method of bionic design, the mushroom morphological structure is applied to the design of covering-layer structure of driving drum surface of belt conveyor. Superelastic rubber with large deformation is adopted as the covering-layer material. Nonlinear constitutive model of rubber, which is of superelasticity and large deformation, is established. The stress states and deformation principles of driving drums including both bionic covering-layer and common covering-layer are obtained by static intensity analysis with Finite Element Analysis (FEA) software ANSYS. The values of the stress and strain on the driving drum surface are gotten and the dangerous area is determined. FEA results show that the superelastic convexity surface structure can enlarge the contact area between the driving drum and viscoelastic belt. The results also show that in comparison with common driving drum, the bionic surface driving drum can not only increase the friction coefficient between drum and belt but also prolong its service life.     

Modes of Continuity and Change in Action Sign Systems

ABSTRACT

This paper opens with stories of continuity and change from ethnographic accounts. It proceeds to a brief examination of the use of film as a recording device for action sign systems, then to the work of two archaeologists in the field of dance and human movement. Next, the recording of sign languages is examined, and finally a case of recent transformation of a ritual (the Dominican rite of the Catholic Mass) is explored, followed by an exposure of some of the reasons why “transformations” occur in rituals, dances, and sign languages throughout the world.

Despite the growing interest among the human sciences in bodies, the notion of moving persons and their signifying acts/actions tends to remain absent from ethnographic accounts and sociocultural theory. Once it is realized that (1) people enact their selves to each other in words, movement, and other modes of action, and that (2) all human selves are culturally defined, as time/space itself is culturally defined, it then becomes possible to develop strategies for a systematic investigation of human actions.

It is argued that the adoption of movement literacy not only as a methodological resource, but as a further development in the evolution of social scientific disciplines, seems necessary. When literacy enters the picture, the understanding of continuity and change in patterned human movement across time will finally come into its own.     

Dance and early childhood cognition: The Isadora Effect

ABSTRACT

This article proposes the existence of an Isadora Effect: the propositions that motor development plays a primal role in brain development, and the first understanding of symbolic meaning among young children occurs from an understanding of movement and gesture. Anecdotal evidence for the past few decades has demonstrated that dance education and the early use of symbolic movement greatly enhance cognitive development in young children. The author presents (a) background and historical information about dance in early childhood in the United States; (b) research in which physical, emotional, and social development has served the backbone for rationalizing inclusion of dance in early education; (c) The Isadora Effect in early childhood dance education and its relationship to cognitive development, brain development, and intelligence; (d) the 21st Century Skills in relation to early childhood development and dance education; and (e) early childhood dance education and the National Core Arts Standards. The author makes three recommendations for improving the development of American youth relative to early childhood dance education: increased inclusion of creative movement and dance in early childhood curricula, scientific study by the pediatric and neurological communities to investigate effects of motor development and early symbolic movement on brain development and cognitive growth, and ways dance educators can communicate with policy makers about the kinds of support needed to make the first two recommendations a reality.     

Visual motor imagery predominance in professional Spanish dancers

Abstract

Purpose: The main objectives of the study were to analyse the predominant motor imagery modality used by professional Spanish dancers and to compare Spanish dancers’ ability to perform mental motor imagery with that of non-dancers, and to analyse differences between male and female dancers. As a secondary aim, to compare the motor imagery ability between two styles of Spanish dance: classical Spanish dancers and Flamenco dancers.

Methods: A total of 74 participants were classified into two groups: professional Spanish dancers (n?=?37) and sedentary participants (n?=?37). The professional Spanish dancer group was composed of two dance disciplines: flamenco dancers (n?=?17), and classical dancers (n?=?20).

Results: Professional Spanish dancers used predominantly visual imagery modalities over kinesthetics to generate motor imagery, with a moderate effect size (p?<?.01, d?=?0.68). Regarding the ability to generate motor imagery, significant intergroup differences between professional Spanish dancers and sedentary participants were observed in all variables, with a large effect size (p?<?.05, d?>?0.80). Differences were obtained between men and women among non-dancers group (t?=??3.34; p?=?.03; d?=?0.5). No differences between Flamenco and classical dancers were observed.

Conclusion: Visual motor imagery modality was easier than the kinaesthetic modality in the generation of motor imagery for professional Spanish dancers regardless of the dance style. Spanish dancers had a greater ability to perform motor imagery compared with non-dancer individuals, needing less time to perform these mental tasks. Men non-dancers had a greater ability to generate motor imagery than women. Reinforcing the training of kinaesthetic motor imagery might be useful for professional Spanish dancers.     

Large-Scale Autotrophic Culture of Euglena gracilis*

SYNOPSIS. Large quantities of autotrophic Euglena gracilis can be obtained in a short time using simple and inexpensive equipment. Cultures grown in flasks on a rotary shaker are transferred to a polyethylene drum containing 180 liters of medium. The drum, which is illuminated with both internal and external fluorescent lamps, contains a coil of vinyl tubing carrying tap water for temperature control and 2 vinyl tubes for air and CO₂. Sterilization of the drum or the medium was unnecessary, but can be accomplished by gassing the drum with ethylene oxide or overnight exposure to germicidal lamps and by dispensing the medium into the drum through a large Millipore apparatus. Yields of 289–330 g of fresh weight material have been obtained after one week's growth. Shorter growth periods yielded 134–160 g of fresh weight material. Ten g of purified chloroplasts have been obtained from 160 g of cells grown in this manner.     

Use of Biochronology to Examine Interactions of Freshwater Drum, Walleye and Yellow Perch in the Red Lakes of Minnesota

Growth histories for freshwater drum, Aplodinotus grunniens, walleye, Stizostedion vitreum, and yellow perch, Perca flavescens, were constructed using calcified structures for the period 1947 through 1996 for the Red Lakes, Minnesota. Increased walleye growth and decreased yellow perch growth were observed over the period from 1983 to 1996, which are attributed to intensive fishing resulting in decreased intraspecific competition in walleye and increased intraspecific competition in yellow perch through release from predation. Strong year-classes of yellow perch were positively correlated with walleye growth (r=0.57, p-value=0.042). There was no evidence for interactions of walleye or yellow perch with freshwater drum. Freshwater drum growth (r=0.680, p-value=0.0001) was more highly correlated with temperature than were walleye (r=0.386, p-value=0.006) and yellow perch growth (r=0.303, p-value=0.036).     

Use of Comparative Genomics to Develop EST-SSRs for Red Drum (Sciaenops ocellatus)

Microsatellites physically linked to expressed sequence tags (EST-SSRs) are an important resource for linkage mapping and comparative genomics, and data mining in publicly available EST databases is a common strategy for EST-SSR discovery. At present, many species lack species-specific EST sequence data needed for the efficient characterization of EST-SSRs. This paper describes the discovery and development of EST-SSRs for red drum (Sciaenops ocellatus), an estuarine-dependent sciaenid species of economic importance in the USA and elsewhere, using a phylogenetically informed, comparative genomics approach to primer design. The approach entailed comparing existing genomic resources from species closely allied phylogenetically to red drum, with resources from more distantly related outgroup species. By taking into account the degree to which flanking regions are conserved across taxa, the efficiency of PCR primer design was increased greatly. The amplification success rate for primers designed for red drum was 100?% when using EST libraries from confamilial species and 92?% when using an EST library from a species in the same suborder. The primers developed also amplified EST-SSRs in a wide range of perciform fishes, suggesting potential use in comparative genomics. This study demonstrates that EST-SSRs can be efficiently developed for an organism when limited species-specific data are available by exploiting genomic resources from well-studied species, even those at extended phylogenetic distances.     

The Function of Ceremonial Sexual Intercourse Among the Northern Plains Indians

Abstract

Sexual intimacy as a means of transferring spiritual power appears to have been a Mandan-Hidatsa ceremonial trait borrowed by three Algonkian Plains tribes as part of the graded men’s societies complex. The Algonkian tribes modified the rite, which in the village tribes emphasized the role of father’s clan. The Arapaho emphasized the cosmic symbolism of the rite, the Atsina made it a test of self-discipline, and the Blackfoot stressed the dangerous power commanded by those who performed it. These modifications parallel the differences in kinship structure between village and nomadic Plains tribes discussed by Eggan.     

Incorporating Non-Coding Annotations into Rare Variant Analysis

BackgroundThe success of collapsing methods which investigate the combined effect of rare variants on complex traits has so far been limited. The manner in which variants within a gene are selected prior to analysis has a crucial impact on this success, which has resulted in analyses conventionally filtering variants according to their consequence. This study investigates whether an alternative approach to filtering, using annotations from recently developed bioinformatics tools, can aid these types of analyses in comparison to conventional approaches.ConclusionIncorporating variant annotations from non-coding bioinformatics tools should prove to be a valuable asset for rare variant analyses in the future. Filtering by variant consequence is only possible in coding regions of the genome, whereas utilising non-coding bioinformatics annotations provides an opportunity to discover unknown causal variants in non-coding regions as well. This should allow studies to uncover a greater number of causal variants for complex traits and help elucidate their functional role in disease.     

Application of Beneficial Microorganisms to Seeds during Drum Priming

Five microbial plant growth promoters or biocontrol agents (Pseudomonas fluorescens CHA0, Pseudomonas sp. AB842, Bacillus subtilis MBI600, Trichoderma harzianum T22 and T. virens G20) were assessed for ability to proliferate on seeds of carrot, parsnip and leek. In small-scale priming systems, both pseudomonads and MBI600 (when applied as cells) at levels between 10⁵ and 10⁶ cfu g^?1 seed were able to colonise all seeds at the end of priming (240 h) despite initial poor recovery after addition of the cells in some cases. Pf CHA0 was a particularly aggressive seed coloniser often comprising the total pseudomonad population at the end of priming. Drying the seed after priming resulted in &lt;1 log₁₀ cfu g^?1 seed loss for the pseudomonads but greater losses for MBI600 on carrot and leek seed. Application of spores of MBI600 resulted in little loss in cfu g^?1 seed following addition of the cells and these levels were maintained throughout the priming period and after drying back. Both T22 and G20 were recovered from carrot and parsnip at the end of priming and in general reflected survival of the inoculum rather than proliferation. T22 and G20 could not be recovered from leek seed following priming. Comparisons were made between proliferation and survival in large-scale drum priming with post-priming application of microorganisms. Pf CHA0 proliferated on carrot and parsnip seed during drum priming and survived the drying back process whereas there was no recovery when applied as a post-priming treatment. In contrast, MBI600 could not be recovered when applied during priming as cells, whereas recovery was good when applied post-priming as spores. T22 spores could be applied in either manner. Post-priming application of metalaxyl and thiabendazole had variable effects on microorganism recovery. The significance of the application of microorganisms to seeds during priming is discussed.