WorldWideScience

Sample records for achieve high foraging

  1. Effect of forage quality in faeces from different ruminant species fed high and low quality forage

    Jalali, A R; Nørgaard, P; Nielsen, M O;

    2010-01-01

    Effect of forage quality in faeces from different ruminant species fed high and low quality forage......Effect of forage quality in faeces from different ruminant species fed high and low quality forage...

  2. Bust economics: foragers choose high quality habitats in lean times.

    Bleicher, Sonny S; Dickman, Christopher R

    2016-01-01

    In environments where food resources are spatially variable and temporarily impoverished, consumers that encounter habitat patches with different food density should focus their foraging initially where food density is highest before they move to patches where food density is lower. Increasing missed opportunity costs should drive individuals progressively to patches with lower food density as resources in the initially high food density patches deplete. To test these expectations, we assessed the foraging decisions of two species of dasyurid marsupials (dunnarts: Sminthopsis hirtipes and S. youngsoni) during a deep drought, or bust period, in the Simpson Desert of central Australia. Dunnarts were allowed access to three patches containing different food densities using an interview chamber experiment. Both species exhibited clear preference for the high density over the lower food density patches as measured in total harvested resources. Similarly, when measuring the proportion of resources harvested within the patches, we observed a marginal preference for patches with initially high densities. Models analyzing behavioral choices at the population level found no differences in behavior between the two species, but models analyzing choices at the individual level uncovered some variation. We conclude that dunnarts can distinguish between habitat patches with different densities of food and preferentially exploit the most valuable. As our observations were made during bust conditions, experiments should be repeated during boom times to assess the foraging economics of dunnarts when environmental resources are high. PMID:26839751

  3. Bust economics: foragers choose high quality habitats in lean times

    Dickman, Christopher R.

    2016-01-01

    In environments where food resources are spatially variable and temporarily impoverished, consumers that encounter habitat patches with different food density should focus their foraging initially where food density is highest before they move to patches where food density is lower. Increasing missed opportunity costs should drive individuals progressively to patches with lower food density as resources in the initially high food density patches deplete. To test these expectations, we assessed the foraging decisions of two species of dasyurid marsupials (dunnarts: Sminthopsis hirtipes and S. youngsoni) during a deep drought, or bust period, in the Simpson Desert of central Australia. Dunnarts were allowed access to three patches containing different food densities using an interview chamber experiment. Both species exhibited clear preference for the high density over the lower food density patches as measured in total harvested resources. Similarly, when measuring the proportion of resources harvested within the patches, we observed a marginal preference for patches with initially high densities. Models analyzing behavioral choices at the population level found no differences in behavior between the two species, but models analyzing choices at the individual level uncovered some variation. We conclude that dunnarts can distinguish between habitat patches with different densities of food and preferentially exploit the most valuable. As our observations were made during bust conditions, experiments should be repeated during boom times to assess the foraging economics of dunnarts when environmental resources are high. PMID:26839751

  4. Bat guilds, a concept to classify the highly diverse foraging and echolocation behaviors of microchiropteran bats

    AnnetteDenzinger

    2013-07-01

    Full Text Available Throughout evolution the foraging and echolocation behaviors as well as the motor systems of bats have been adapted to the tasks they have to perform while searching and acquiring food. When bats exploit the same class of environmental resources in a similar way, they perform comparable tasks and thus share similar adaptations independent of their phylogeny. Species with similar adaptations are assigned to guilds or functional groups. Habitat type and foraging mode mainly determine the foraging tasks and thus the adaptations of bats. Therefore we use habitat type and foraging mode to define seven guilds. The habitat types open, edge and narrow space are defined according to the bats’ echolocation behavior in relation to the distance between bat and background or food item and background. Bats foraging in the aerial, trawling, flutter detecting, or active gleaning mode use only echolocation to acquire their food. When foraging in the passive gleaning mode bats do not use echolocation but rely on sensory cues from the food item to find it. Bat communities often comprise large numbers of species with a high diversity in foraging areas, foraging modes, and diets. The assignment of species living under similar constraints into guilds identifies pattern of community structure and helps to understand the factors that underlie the organization of highly diverse bat communities. Bat species from different guilds do not compete for food as they differ in their foraging behavior and in the environmental resources they use. However, sympatric living species belonging to the same guild often exploit the same class of resources. To avoid competition they should differ in their niche dimensions. The fine grain structure of bat communities below the rather coarse classification into guilds is determined by mechanisms that result in niche partitioning.

  5. Bat guilds, a concept to classify the highly diverse foraging and echolocation behaviors of microchiropteran bats.

    Denzinger, Annette; Schnitzler, Hans-Ulrich

    2013-01-01

    Throughout evolution the foraging and echolocation behaviors as well as the motor systems of bats have been adapted to the tasks they have to perform while searching and acquiring food. When bats exploit the same class of environmental resources in a similar way, they perform comparable tasks and thus share similar adaptations independent of their phylogeny. Species with similar adaptations are assigned to guilds or functional groups. Habitat type and foraging mode mainly determine the foraging tasks and thus the adaptations of bats. Therefore, we use habitat type and foraging mode to define seven guilds. The habitat types open, edge and narrow space are defined according to the bats' echolocation behavior in relation to the distance between bat and background or food item and background. Bats foraging in the aerial, trawling, flutter detecting, or active gleaning mode use only echolocation to acquire their food. When foraging in the passive gleaning mode bats do not use echolocation but rely on sensory cues from the food item to find it. Bat communities often comprise large numbers of species with a high diversity in foraging areas, foraging modes, and diets. The assignment of species living under similar constraints into guilds identifies patterns of community structure and helps to understand the factors that underlie the organization of highly diverse bat communities. Bat species from different guilds do not compete for food as they differ in their foraging behavior and in the environmental resources they use. However, sympatric living species belonging to the same guild often exploit the same class of resources. To avoid competition they should differ in their niche dimensions. The fine grain structure of bat communities below the rather coarse classification into guilds is determined by mechanisms that result in niche partitioning. PMID:23840190

  6. Climatic and management factors affecting the forage yield and quality of a high density mulberry forage bank established under low input tropical farming conditions

    Martin-Martin, Giraldo

    2015-01-01

    Effects of year season (SEAS), organic fertilization (N) and harvest frequency (FREQ) on forage yield and composition were evaluated in a high density mulberry forage bank, established under low input tropical farming conditions. The experiment, replicated 2 consecutive years, was arranged in 18 treatments resulting from a 3 × 3 × 2 factorial design combining 3 FREQ (60, 90 and 120 d), 3 N rates (100, 300 and 500 kg N/ha/year) and the 2 seasons (RAIN and DRY). Forage yield, leaf to stem ratio...

  7. Catholic High Schools and Rural Academic Achievement.

    Sander, William

    1997-01-01

    A study of national longitudinal data examined effects of rural Catholic high schools on mathematics achievement, high school graduation rates, and the likelihood that high school graduates attend college. Findings indicate that rural Catholic high schools had a positive effect on mathematics test scores and no effect on graduation rates or rates…

  8. Ultra-High Foraging Rates of Harbor Porpoises Make Them Vulnerable to Anthropogenic Disturbance.

    Wisniewska, Danuta Maria; Johnson, Mark; Teilmann, Jonas; Rojano-Doñate, Laia; Shearer, Jeanne; Sveegaard, Signe; Miller, Lee A; Siebert, Ursula; Madsen, Peter Teglberg

    2016-06-01

    The question of how individuals acquire and allocate resources to maximize fitness is central in evolutionary ecology. Basic information on prey selection, search effort, and capture rates are critical for understanding a predator's role in its ecosystem and for predicting its response to natural and anthropogenic disturbance. Yet, for most marine species, foraging interactions cannot be observed directly. The high costs of thermoregulation in water require that small marine mammals have elevated energy intakes compared to similar-sized terrestrial mammals [1]. The combination of high food requirements and their position at the apex of most marine food webs may make small marine mammals particularly vulnerable to changes within the ecosystem [2-4], but the lack of detailed information about their foraging behavior often precludes an informed conservation effort. Here, we use high-resolution movement and prey echo recording tags on five wild harbor porpoises to examine foraging interactions in one of the most metabolically challenged cetacean species. We report that porpoises forage nearly continuously day and night, attempting to capture up to 550 small (3-10 cm) fish prey per hour with a remarkable prey capture success rate of >90%. Porpoises therefore target fish that are smaller than those of commercial interest, but must forage almost continually to meet their metabolic demands with such small prey, leaving little margin for compensation. Thus, for these "aquatic shrews," even a moderate level of anthropogenic disturbance in the busy shallow waters they share with humans may have severe fitness consequences at individual and population levels. PMID:27238281

  9. High precision during food recruitment of experienced (reactivated) foragers in the stingless bee Scaptotrigona mexicana (Apidae, Meliponini)

    Sánchez, Daniel; Nieh, James C.; Hénaut, Yann; Cruz, Leopoldo; Vandame, Rémy

    Several studies have examined the existence of recruitment communication mechanisms in stingless bees. However, the spatial accuracy of location-specific recruitment has not been examined. Moreover, the location-specific recruitment of reactivated foragers, i.e., foragers that have previously experienced the same food source at a different location and time, has not been explicitly examined. However, such foragers may also play a significant role in colony foraging, particularly in small colonies. Here we report that reactivated Scaptotrigona mexicana foragers can recruit with high precision to a specific food location. The recruitment precision of reactivated foragers was evaluated by placing control feeders to the left and the right of the training feeder (direction-precision tests) and between the nest and the training feeder and beyond it (distance-precision tests). Reactivated foragers arrived at the correct location with high precision: 98.44% arrived at the training feeder in the direction trials (five-feeder fan-shaped array, accuracy of at least +/-6° of azimuth at 50 m from the nest), and 88.62% arrived at the training feeder in the distance trials (five-feeder linear array, accuracy of at least +/-5 m or +/-10% at 50 m from the nest). Thus, S. mexicana reactivated foragers can find the indicated food source at a specific distance and direction with high precision, higher than that shown by honeybees, Apis mellifera, which do not communicate food location at such close distances to the nest.

  10. Identifying learning techniques among high achievers

    Shanmukananda P

    2013-04-01

    Full Text Available Background: In every college, it is noticed that in spite of being exposed to the same teaching modalities and adopting seemingly similar strategies, some students perform much better than their peers. This can be evaluated in the form of better academic performance in the internal assessments they undertake. This project is an endeavor to identify the learning techniques among high achievers which they employ to outperform others. We can also suggest the same to the medium and low achievers so that they can improve their academic performance. This study was conducted to identify different learning techniques adopted by high achievers and suggesting the same to medium and low achievers. Methods: After obtaining clearance from the institutional ethics committee, the high achievers were identified by selecting the upper third of the students in the ascending order of marks obtained in the consecutive three internal assessments in three consecutive batches. The identity of the students was not revealed. They were then administered an open ended questionnaire which addressed relevant issues. The most common and feasible techniques will be suggested to the medium and low achievers. Results: The respondents’ (n=101 replies were analyzed by calculating the percentages of responses, and assessing based on that, which were the most frequently adapted techniques by these high achievers Conclusions: High-achievers have a diligent study pattern; they not only study regularly, but also involve in group discussions and approach their teachers when in doubt. Additionally, they refer to other sources of information like the internet, demonstrating a proactive attitude towards studies. [Int J Basic Clin Pharmacol 2013; 2(2.000: 203-207

  11. Identifying learning techniques among high achievers

    Shanmukananda P; L. Padma

    2013-01-01

    Background: In every college, it is noticed that in spite of being exposed to the same teaching modalities and adopting seemingly similar strategies, some students perform much better than their peers. This can be evaluated in the form of better academic performance in the internal assessments they undertake. This project is an endeavor to identify the learning techniques among high achievers which they employ to outperform others. We can also suggest the same to the medium and low achievers ...

  12. Student Perceptions of High-Achieving Classmates

    Händel, Marion; Vialle, Wilma; Ziegler, Albert

    2013-01-01

    The reported study investigated students' perceptions of their high-performing classmates in terms of intelligence, social skills, and conscientiousness in different school subjects. The school subjects for study were examined with regard to cognitive, physical, and gender-specific issues. The results show that high academic achievements in…

  13. Paternal kin recognition in the high frequency / ultrasonic range in a solitary foraging mammal

    Kessler Sharon E; Scheumann Marina; Nash Leanne T; Zimmermann Elke

    2012-01-01

    Abstract Background Kin selection is a driving force in the evolution of mammalian social complexity. Recognition of paternal kin using vocalizations occurs in taxa with cohesive, complex social groups. This is the first investigation of paternal kin recognition via vocalizations in a small-brained, solitary foraging mammal, the grey mouse lemur (Microcebus murinus), a frequent model for ancestral primates. We analyzed the high frequency/ultrasonic male advertisement (courtship) call and alar...

  14. Achieving High Performance Perovskite Solar Cells

    Yang, Yang

    2015-03-01

    Recently, metal halide perovskite based solar cell with the characteristics of rather low raw materials cost, great potential for simple process and scalable production, and extreme high power conversion efficiency (PCE), have been highlighted as one of the most competitive technologies for next generation thin film photovoltaic (PV). In UCLA, we have realized an efficient pathway to achieve high performance pervoskite solar cells, where the findings are beneficial to this unique materials/devices system. Our recent progress lies in perovskite film formation, defect passivation, transport materials design, interface engineering with respect to high performance solar cell, as well as the exploration of its applications beyond photovoltaics. These achievements include: 1) development of vapor assisted solution process (VASP) and moisture assisted solution process, which produces perovskite film with improved conformity, high crystallinity, reduced recombination rate, and the resulting high performance; 2) examination of the defects property of perovskite materials, and demonstration of a self-induced passivation approach to reduce carrier recombination; 3) interface engineering based on design of the carrier transport materials and the electrodes, in combination with high quality perovskite film, which delivers 15 ~ 20% PCEs; 4) a novel integration of bulk heterojunction to perovskite solar cell to achieve better light harvest; 5) fabrication of inverted solar cell device with high efficiency and flexibility and 6) exploration the application of perovskite materials to photodetector. Further development in film, device architecture, and interfaces will lead to continuous improved perovskite solar cells and other organic-inorganic hybrid optoelectronics.

  15. What Characterises High Achieving Students’ Mathematical Reasoning?

    Haavold, Per Øystein

    2011-01-01

    This study investigates high achieving students’ mathematical reasoning when given an unfamiliar trigonometric equation. The findings indicate that the students’ way of thinking is strongly linked with imitative reasoning and only when they received some form of guidance, were they able to display flexible and creative mathematical reasoning.

  16. Low and high achievers in math

    Overgaard, Steffen; Tonnesen, Pia Beck; Weng, Peter;

    2015-01-01

    In this session we will present the results of the preliminary analysis of the qualitative and quantitative data, which can be used to enhance the teaching of low and high mathematics achievers so as to increase their mathematical knowledge and confidence....

  17. Foraging segregation and genetic divergence between geographically proximate colonies of a highly mobile seabird

    Wiley, Anne E.; Welch, Andreanna J.; Ostrom, P.H.; James, Helen F.; Stricker, C.A.; Fleischer, R.C.; Gandhi, H.; Adams, J.; Ainley, D.G.; Duvall, F.; Holmes, N.; Hu, D.; Judge, S.; Penniman, J.; Swindle, K.A.

    2012-01-01

    Foraging segregation may play an important role in the maintenance of animal diversity, and is a proposed mechanism for promoting genetic divergence within seabird species. However, little information exists regarding its presence among seabird populations. We investigated genetic and foraging divergence between two colonies of endangered Hawaiian petrels (Pterodroma sandwichensis) nesting on the islands of Hawaii and Kauai using the mitochondrial Cytochrome b gene and carbon, nitrogen and hydrogen isotope values (?? 13C, ?? 15N and ??D, respectively) of feathers. Genetic analyses revealed strong differentiation between colonies on Hawaii and Kauai, with ?? ST = 0. 50 (p segregation during molt. Feather ??D varied from -69 to 53???. This variation cannot be related solely to an isotopically homogeneous ocean water source or evaporative water loss. Instead, we propose the involvement of salt gland excretion. Our data demonstrate the presence of foraging segregation between proximately nesting seabird populations, despite high species mobility. This ecological diversity may facilitate population coexistence, and its preservation should be a focus of conservation strategies. ?? 2011 Springer-Verlag (outside the USA).

  18. Academic achievement in high functioning autistic individuals.

    Minshew, N J; Goldstein, G; Taylor, H G; Siegel, D J

    1994-04-01

    Academic achievement levels in 54 high functioning (IQ > 70) autistic subjects were compared with those of 41 normal controls, who did not differ significantly in age, IQ, gender, race, or SES from the autistic subjects. The measures of academic achievement used included portions of the Detroit Tests of Learning Aptitude-2, the Woodcock Reading Mastery Test, and the Kaufman Test of Educational Achievement. Based on prior neuropsychological findings, it was hypothesized that autistic subjects would not differ from controls on subtests assessing mechanical and procedural skills, but would differ on subtests measuring comprehension and interpretive skills. As predicted, the autistic subjects performed significantly less well than controls on comprehension tasks, but not on mechanical reading, spelling, and computational tasks. This pattern is at variance with the typical academic profile of individuals with disabilities in reading or spelling, but shares some features with the nonverbal learning disabilities. PMID:8021313

  19. Devclopment of the Forage Riees WithHigh Protein Gontent in Hunan

    2000-01-01

    @@The meaning of the high protein forage rices Rices may be classified by itsuses as human'sfood.animal's on poultry's feed,or the raw materials of various industries.For ricesused as people's food.its breeding objectives are focused on the varietal characters such as medium amylose content .high rale of head rice.hyaline smoothmilled grains and delicious taste:for those used in making rice meal.beer,gourmet powder,etc.specially on high amylose content:while in wine making,it should be focused on big white belly and white beart,but low protein content in particular.As for the rices used as feed,the most important is its high rate of pre -protein in the brown rice ,leaving its grain appearance out of consideration.Thcrefore,the so called forage rice (FR)sgiykd be a kind of paddy rice with high pre-protein content of brown rice(≥8.25%)and high grain yicld (≥8.25t/ha),to be used as the composition of the animal feed by applying cultivation management oplimized under the suitable growth duration and strong pest resistance.

  20. Lactation performance of dairy cows fed yeast-derived microbial protein in low- and high-forage diets.

    Manthey, A K; Kalscheur, K F; Garcia, A D; Mjoun, K

    2016-04-01

    The objective of this study was to investigate the effect of substituting soybean meal products with yeast-derived microbial protein (YMP) on lactation performance in diets containing 2 forage-to-concentrate ratios. Sixteen Holstein cows (4 primiparous and 12multiparous) were randomly assigned to multiple 4×4 Latin squares with a 2×2 factorial arrangement of treatments. Diets contained low (LF; 45% of diet DM) or high forage (HF; 65% of diet DM) and YMP at 0 (NYMP) or 2.25% (WYMP) of the diet. The forage mix consisted of 67% corn silage and 33% alfalfa hay on a DM basis. No interactions of forage and YMP were noted for any of the production parameters measured. Feed efficiency (energy-corrected milk/dry matter intake) was greater for cows fed NYMP compared with WYMP. Regardless of the addition of YMP, cows fed LF had greater dry matter intake and produced more milk than cows fed HF. In addition, cows fed LF produced more energy-corrected milk than those fed HF. Milk fat percentage was lower in cows fed LF compared with HF, whereas fat yield was similar between forage concentrations. Fat yield tended to decrease with feeding YMP. Interactions of forage and YMP were observed for propionate concentration, acetate and propionate proportion, and acetate-to-propionate ratio. A tendency for an interaction of forage and YMP was also noted for ruminal pH. Cows fed HF diets had greater ruminal ammonia and butyrate concentrations, as well as proportion of butyrate. Arterial concentrations of Ile, Leu, Met, Thr, and Val were greater in cows fed LF. Cows fed NYMP had greater arterial concentrations of Ile, Lys, Trp, and Val than cows fed WYMP. Substitution of soybean proteins with YMP did not improve performance or feed efficiency of high-producing dairy cows regardless of the forage-to-concentrate ratio of the diet. PMID:26851859

  1. A high lysine mutant of winter forage barley induced by Co60 gamma rays

    It is typical of the induced high lysine mutant of winter forage barley that compared to the parental form its height is reduced 10-15 cm. Besides, it is distinguished by greatly shrunken endosperm and, therefore, reduced (24.32%) 1000 grain weight. The crude protein content of the grain is 17.37%, and of lysine - 5,46 g/16 g N. The gene controlling endosperm is linked with the gene governing synthesis of more lysine. The test of allelisms for that gene has revealed that it is not allelic to the gene of Hiproly, Notch 1 and Riso-1508

  2. Paternal kin recognition in the high frequency / ultrasonic range in a solitary foraging mammal

    Kessler Sharon E

    2012-11-01

    Full Text Available Abstract Background Kin selection is a driving force in the evolution of mammalian social complexity. Recognition of paternal kin using vocalizations occurs in taxa with cohesive, complex social groups. This is the first investigation of paternal kin recognition via vocalizations in a small-brained, solitary foraging mammal, the grey mouse lemur (Microcebus murinus, a frequent model for ancestral primates. We analyzed the high frequency/ultrasonic male advertisement (courtship call and alarm call. Results Multi-parametric analyses of the calls’ acoustic parameters and discriminant function analyses showed that advertisement calls, but not alarm calls, contain patrilineal signatures. Playback experiments controlling for familiarity showed that females paid more attention to advertisement calls from unrelated males than from their fathers. Reactions to alarm calls from unrelated males and fathers did not differ. Conclusions 1 Findings provide the first evidence of paternal kin recognition via vocalizations in a small-brained, solitarily foraging mammal. 2 High predation, small body size, and dispersed social systems may select for acoustic paternal kin recognition in the high frequency/ultrasonic ranges, thus limiting risks of inbreeding and eavesdropping by predators or conspecific competitors. 3 Paternal kin recognition via vocalizations in mammals is not dependent upon a large brain and high social complexity, but may already have been an integral part of the dispersed social networks from which more complex, kin-based sociality emerged.

  3. Bed disturbance via foraging fish increases bedload transport during subsequent high flows and is controlled by fish size and species

    Pledger, A. G.; Rice, S. P.; Millett, J.

    2016-01-01

    Benthic foraging by fish can modify the nature and rates of fine sediment accrual and the structure and topography of coarse-grained fluvial substrates, with the potential to alter bed material characteristics, particle entrainment thresholds, and bedload transport fluxes. However, knowledge of what controls the nature, extent, and intensity of benthic foraging and the consequent influence of these controls on geomorphic impact remain rudimentary. An ex-situ experiment utilising Barbel Barbus barbus and Chub Leuciscus cephalus extended previous work by considering the role of fish size and species as controls of sediment disturbance by foraging and the implications for bed material characteristics and bedload transport. In a laboratory flume, changes in bed microtopography and structure were measured when a water-worked bed of 5.6-22.6 mm gravels was exposed to four size classes of Barbel (4-5″, 5-6″, 6-8″, 8-10″ in length) and a single size class of Chub (8-10″). In line with other studies that have investigated animal size as a control of zoogeomorphic agency, increasing the size of Barbel had a significant effect on measured disturbance and transport metrics. Specifically, the area of disturbed substrate, foraging depth, and the fish's impact on microtopographic roughness and imbrication all increased as a function of fish size. In a comparison of the foraging effects of like-sized Barbel and Chub, 8-10″ in length, Barbel foraged a larger area of the test bed and had a greater impact on microtopographic roughness and sediment structure. Relative to water-worked beds that were not foraged, bed conditioning by both species was associated with increased bedload transport during the subsequent application of high flows. However, the bedload flux after foraging by Barbel, which is a specialist benthivore, was 150% higher than that following foraging by Chub, which feed opportunistically from the bed, and the total transported mass of sediment was 98

  4. Academic Attitudes of High Achieving and Low Achieving Academically Able Black Male Adolescents.

    Trotter, John Rhodes

    1981-01-01

    In order to identify the relationships between the attitudes and perceptions of peer pressure and the academic achievement of academically able male adolescents, this study compares the school attitudes of high achieving and low achieving Black male youth. (EF)

  5. Attitudes and Opinions from the Nation's High Achieving Teens: 26th Annual Survey of High Achievers.

    Who's Who among American High School Students, Lake Forest, IL.

    A national survey of 3,351 high achieving high school students (junior and senior level) was conducted. All students had A or B averages. Topics covered include lifestyles, political beliefs, violence and entertainment, education, cheating, school violence, sexual violence and date rape, peer pressure, popularity, suicide, drugs and alcohol,…

  6. Achieving High Data Throughput in Research Networks

    WarrenMatthews; LesCottrell

    2001-01-01

    After less than a year of operation ,the BaBar experiment at SLAC has collected almost 100 million particle collision events in a database approaching 165TB.Around 20 TB of data has been exported via the Internet to the BaBar regional center at IN2P3 in Lyon,France,and around 40TB of simulated data has been imported from the Lawrence Livermore National Laboratory(LLNL),BaBar Collaborators plan to double data collection each year and export a third of the data to IN2P3.So within a few years the SLAC OC3 (155Mbps) connection will be fully utilized by file transfer to France alone.Upgrades to infrastructure is essential and detailed understanding of performance issues and the requirements for reliable high throughput transfers is critical.In this talk results from active and passive monitoring and direct measurements of throughput will be reviewed.Methods for achieving the ambitious requirements will be discussed.

  7. Factors affecting forage stand establishment

    Sulc R.M.

    1998-01-01

    Significant advances have been made in our knowledge of forage seed physiology, technology, and stand establishment practices; however, stand establishment continues to be one of the most common production problems affecting forage crops in the USA. There is a need for research on stand establishment of forage crops under abiotic and biotic stress. Although the forage seed industry produces and markets seed of high quality, new methods of assessing seed vigor are needed and their use should b...

  8. Ultra-high foraging rates of harbour porpoises make them vulnerable to anthropogenic disturbance

    Wisniewska, Danuta; Johnson, Mark; Teilmann, Jonas;

    2016-01-01

    and prey echo recording tags on five wild harbour porpoises to examine foraging interactions in one of the most metabolically challenged cetacean species. We report that porpoises forage nearly continuously day and night, attempting to capture up to 550 small (3-10 cm) fish prey per hour with a...

  9. Does High School Homework Increase Academic Achievement?

    Kalenkoski, Charlene Marie; Wulff Pabilonia, Sabrina

    2014-01-01

    Although previous research has shown that homework improves students' academic achievement, the majority of these studies use data on students' homework time from retrospective questionnaires, which are less accurate than time-diary data. However, most time-diary data sets do not contain outcome measures, and thus are limited in the questions they can answer. One data set that does have both time-diary and outcome information is the combined Child Development Supplement (CDS) and the Transiti...

  10. Bat guilds, a concept to classify the highly diverse foraging and echolocation behaviors of microchiropteran bats

    AnnetteDenzinger

    2013-01-01

    Throughout evolution the foraging and echolocation behaviors as well as the motor systems of bats have been adapted to the tasks they have to perform while searching and acquiring food. When bats exploit the same class of environmental resources in a similar way, they perform comparable tasks and thus share similar adaptations independent of their phylogeny. Species with similar adaptations are assigned to guilds or functional groups. Habitat type and foraging mode mainly determine the foragi...

  11. Transfer of 226Ra and 210Pb to forage and milk in a Brazilian high natural radioactivity region

    The Pocos de Caldas plateau, where the Brazilian uranium mine and mill facilities are located, is a natural high radioactivity region. A study has been carried out in order to assess the environmental transport of the natural radionuclides in the region. The present work is concerned with the transfer of 226Ra and 210Pb to forage and milk. Similar concentrations for both radionuclides were found in soil samples. In forage 210Pb concentrations are one order of magnitude higher than those of 226Ra, however, the milk samples presented higher values for 226Ra concentrations. The average forage to milk concentration factors are of the order of 10-4 d.l-1 for 226Ra and 10-5 d.l-1 for 210Pb. Regarding transfer mechanisms, the results suggest the foliar deposition as the main pathway for 210Pb uptake by the forage. In contrast, for 226Ra the root uptake appears as the main transfer pathway. (author)

  12. High sea surface temperatures driven by a strengthening current reduce foraging success by penguins.

    Carroll, Gemma; Everett, Jason D; Harcourt, Robert; Slip, David; Jonsen, Ian

    2016-01-01

    The world's oceans are undergoing rapid, regionally specific warming. Strengthening western boundary currents play a role in this phenomenon, with sea surface temperatures (SST) in their paths rising faster than the global average. To understand how dynamic oceanography influences food availability in these ocean warming "hotspots", we use a novel prey capture signature derived from accelerometry to understand how the warm East Australian Current shapes foraging success by a meso-predator, the little penguin. This seabird feeds on low trophic level species that are sensitive to environmental change. We found that in 2012, prey capture success by penguins was high when SST was low relative to the long-term mean. In 2013 prey capture success was low, coincident with an unusually strong penetration of warm water. Overall there was an optimal temperature range for prey capture around 19-21 °C, with lower success at both lower and higher temperatures, mirroring published relationships between commercial sardine catch and SST. Spatially, higher SSTs corresponded to a lower probability of penguins using an area, and lower prey capture success. These links between high SST and reduced prey capture success by penguins suggest negative implications for future resource availability in a system dominated by a strengthening western boundary current. PMID:26923901

  13. Evaluation of barley (hordeum vulgare l.) germplasm for high forage production under salt stress

    To explore high biomass producing salt tolerant cultivars of a potential forage crop barley (Hordeum vulgare L.), 30-day old plants of 105 different accessions from different origin were subjected to saline and non-saline (control) conditions for 45 days. Salinity stress (150 mM NaCl) markedly suppressed plant growth (shoot and/or root fresh and dry weights), chlorophyll pigments (a and b), internal CO/sub 2/ concentration, stomatal conductance, rate of transpiration and photosynthesis, while a considerable salt-induced increase was observed in all fluorescence related attributes including efficiency of photosystem-II (Fv/Fm), co-efficient of non-photochemical quenching (QN), photochemical quenching (QP), and non-photochemical quenching (NPQ) in all 105 accessions of barley. The response of all 105 barley accessions to salt stress varied significantly for all the morpho-physiological attributes determined in the present study. Overall, on the basis of shoot and root dry weights, accessions, 4050, 4053, 4056, 4163, 4228, 4229, 4244, 4245, 4290, 4414, 4415, 4427, 4452, Mahali, Jesto, 4165, 4229, 4249, 4405, 4409, 4426, 4456, and Giza 123 were found superior while accessions, 4245, 4158, 4166, 4246, 4406, 4423, 4441, 4442 4447, 4453 and 4458 inferior under saline conditions. (author)

  14. Achieving High-Temperature Ferromagnetic Topological Insulator

    Katmis, Ferhat

    Topological insulators (TIs) are insulating materials that display conducting surface states protected by time-reversal symmetry, wherein electron spins are locked to their momentum. This unique property opens new opportunities for creating next-generation electronic and spintronic devices, including TI-based quantum computation. Introducing ferromagnetic order into a TI system without compromising its distinctive quantum coherent features could lead to a realization of several predicted novel physical phenomena. In particular, achieving robust long-range magnetic order at the TI surface at specific locations without introducing spin scattering centers could open up new possibilities for devices. Here, we demonstrate topologically enhanced interface magnetism by coupling a ferromagnetic insulator (FMI) to a TI (Bi2Se3); this interfacial ferromagnetism persists up to room temperature, even though the FMI (EuS) is known to order ferromagnetically only at low temperatures (FMI bilayer system. Due to the short range nature of the ferromagnetic exchange interaction, the time-reversal symmetry is broken only near the surface of a TI, while leaving its bulk states unaffected. The topological magneto-electric response originating in such an engineered TI could allow for an efficient manipulation of the magnetization dynamics by an electric field, providing an energy efficient topological control mechanism for future spin-based technologies. Work supported by MIT MRSEC through the MRSEC Program of NSF under award number DMR-0819762, NSF Grant DMR-1207469, the ONR Grant N00014-13-1-0301, and the STC Center for Integrated Quantum Materials under NSF grant DMR-1231319.

  15. Achievement Goals, Learning Strategies and Language Achievement among Peruvian High School Students

    Lennia Matos

    2007-05-01

    Full Text Available We used an achievement goal framework to study the role of motivation in the academic context of a Peruvian sample of 8th to 10th grade high school students (N = 1505. The purpose of this cross-sectional study was to examine the relationship between students' achievement goals, their use of learning strategies and their academic achievement. Multiple Hierarchical Regressions Analyses identified, as predicted, positive effects of mastery goals, including more use of learning strategies and higher academic achievement, and negative effects of performance avoidance goals, including lower academic achievement. Mixed results were found for pursuing performance approach goals, which predicted a greater use of learning strategies, but were unrelated to academic achievement. The present findings support the external validity of achievement goal theory in a sample of students from a culture that is understudied in the achievement goal literature in particular and the motivational literature in general.

  16. Differences in foraging ecology align with genetically divergent ecotypes of a highly mobile marine top predator.

    Jeglinski, Jana W E; Wolf, Jochen B W; Werner, Christiane; Costa, Daniel P; Trillmich, Fritz

    2015-12-01

    Foraging differentiation within a species can contribute to restricted gene flow between ecologically different groups, promoting ecological speciation. Galapagos sea lions (Zalophus wollebaeki) show genetic and morphological divergence between the western and central archipelago, possibly as a result of an ecologically mediated contrast in the marine habitat. We use global positioning system (GPS) data, time-depth recordings (TDR), stable isotope and scat data to compare foraging habitat characteristics, diving behaviour and diet composition of Galapagos sea lions from a western and a central colony. We consider both juvenile and adult life stages to assess the potential role of ontogenetic shifts that can be crucial in shaping foraging behaviour and habitat choice for life. We found differences in foraging habitat use, foraging style and diet composition that aligned with genetic differentiation. These differences were consistent between juvenile and adult sea lions from the same colony, overriding age-specific behavioural differences. Our study contributes to an understanding of the complex interaction of ecological condition, plastic behavioural response and genetic make-up of interconnected populations. PMID:26307593

  17. Adverse foraging conditions may impact body mass and survival of a high Arctic seabird

    Harding, A.M.A.; Welcker, J.; Steen, H.; Hamer, K.C.; Kitaysky, A.S.; Fort, J.; Talbot, S.L.; Cornick, L.A.; Karnovsky, N.J.; Gabrielsen, G.W.; Gremillet, D.

    2011-01-01

    Tradeoffs between current reproduction and future survival are widely recognized, but may only occur when food is limited: when foraging conditions are favorable, parents may be able to reproduce without compromising their own survival. We investigated these tradeoffs in the little auk (Alle alle), a small seabird with a single-egg clutch. During 2005-2007, we examined the relationship between body mass and survival of birds breeding under contrasting foraging conditions at two Arctic colonies. We used corticosterone levels of breeding adults as a physiological indicator of the foraging conditions they encountered during each reproductive season. We found that when foraging conditions were relatively poor (as reflected in elevated levels of corticosterone), parents ended the reproductive season with low body mass and suffered increased post-breeding mortality. A positive relationship between body mass and post-breeding survival was found in one study year; light birds incurred higher survival costs than heavy birds. The results of this study suggest that reproducing under poor foraging conditions may affect the post-breeding survival of long-lived little auks. They also have important demographic implications because even a small change in adult survival may have a large effect on populations of long-lived species. ?? 2011 Springer-Verlag.

  18. Nutrient Utilization, Lactational Performance, and Profitability of Dairy Cows by Feeding Protein Supplements in High-Forage Lactation Diets

    Neal, Kathryn

    2014-01-01

    Due to the increasing cost of soybean meal and concerns of excess N being excreted into the environment, new protein supplements have been developed. Two products that have shown potential in increasing N utilization efficiency are slow release urea (SRU; Optigen) and ruminal escape protein derived from yeast (YMP; DEMP). The objective of this study was to assess the effects of feeding these 2 supplements in high-forage [(54% of total dietary dry matter (DM)] dairy diets on nutrient utilizati...

  19. Achievement Goals, Learning Strategies and Language Achievement among Peruvian High School Students

    Lennia Matos; Willy Lens; Maarten Vansteenkiste

    2007-01-01

    We used an achievement goal framework to study the role of motivation in the academic context of a Peruvian sample of 8th to 10th grade high school students (N = 1505). The purpose of this cross-sectional study was to examine the relationship between students' achievement goals, their use of learning strategies and their academic achievement. Multiple Hierarchical Regressions Analyses identified, as predicted, positive effects of mastery goals, including more use of learning strategies and hi...

  20. Achieving High Quality in the Work of Supreme Audit Institutions

    OECD

    2004-01-01

    This paper focuses primarily on the issue of how to achieve high quality in the audit process. In addition to describing the types of procedures needed to achieve quality, however, it discusses basic principles and those matters of institutional management that create an environment that encourages high quality in an SAI’s work. Audit quality is obtained by a process of identifying and administering the activities needed to achieve the quality objectives of an SAI. All types of SAIs need to u...

  1. A review on studies in forage in China

    LONG Wenxing; YANG Xiaobo; QI Meiying

    2007-01-01

    A review is made of the achievements in the collection,conservation,and genetic diversity of forage germplasm resources;methods and goals for forage breeding;and development and utilization of forage in China.The current problems based on the researches in forage are analyzed,and some suggestions are put forward.

  2. High sea surface temperatures driven by a strengthening current reduce foraging success by penguins

    Gemma Carroll; Everett, Jason D.; Robert Harcourt; David Slip; Ian Jonsen

    2016-01-01

    The world’s oceans are undergoing rapid, regionally specific warming. Strengthening western boundary currents play a role in this phenomenon, with sea surface temperatures (SST) in their paths rising faster than the global average. To understand how dynamic oceanography influences food availability in these ocean warming “hotspots”, we use a novel prey capture signature derived from accelerometry to understand how the warm East Australian Current shapes foraging success by a meso-predator, th...

  3. Utilization of complete rumen modifier on sheep fed high fibrous forages.

    Amlius Thalib

    2010-06-01

    Full Text Available A research to improve livestock productivity and lower enteric methane production on ruminant was conducted by manipulation approach on rumen system using a complete rumen modifier (CRM. An in vivo experiment was carried out using twenty four sheep ( mean weight 18 kg which were distributed into 3 treatment groups of feed additive: I. control ( without treatment: K; II: K + CRM-LG; III: K + CRM-EL. Diet given consisted of fermented rice straw (ad libitum + concentrate containing 16 % protein (400 g/head/day, and drinking water was given ad libitum. The experiment was conducted for 14 weeks based on completely randomized design. By the end of the experiment, animals were placed in the metabolism cages for 2 weeks (ie. 1 week for adaptation and 1 week for data collection. Rumen liquid of each treated animal was taken for the measurement of rumen characteristics. Parameter measuremed were: total gas production; gas composition of CO2 and CH4; in vitro DMD; NH3 and VFA contents; pH; bacterial and protozoal counts; consumption/ DMI; in vivo DMD; ADG and FCR. The results showed that productivity of sheep was improved by CRM treatments followed by lowered enteric methane production. The ADG values of CRM treatments (71.4 to 73.5 g were significantly higher (P < 0.05 than that of control (50 g. The improvement of average daily gain was followed by a better feed conversion (P < 0.05 (ie. 10.6 vs. 12.8. The CRM treatments lowered the percentage of CH4 by 24% compared to Control (P < 0.05. The total and composition of VFA of CRM-treated rumen liquor were significantly different (P<0.05 compared to that of rumen liquor of Control (ie. the total VFA: 85.3 vs 73.5 mM and the percentage of acetic acid: 67.8 vs 60.3%. It is concluded that CRM treatment resulted in positive effects on growth of ruminant fed high fibrous forages such as rice straw and could lower enteric methane production.

  4. Mobility and Student Achievement in High Poverty Schools

    Dalton, Janet Denise

    2013-01-01

    Student mobility is an issue for high poverty schools in the shadow of increased rigor and accountability for student performance. Whereas mobility is not a sole cause for poor achievement, it is a contributing factor for students in poverty who are already considered to be at risk of low achievement. Student mobility creates a hardship for…

  5. Biculturalism and Academic Achievement of African American High School Students

    Rust, Jonathan P.; Jackson, Margo A.; Ponterotto, Joseph G.; Blumberg, Fran C.

    2011-01-01

    Biculturalism was examined as a factor that may positively affect the academic achievement of African American high school students, beyond cultural identity and self-esteem. Hierarchical regression analyses determined that cultural identity and academic self-esteem were important factors for academic achievement, but not biculturalism.…

  6. Tracking and Detracking: High Achievers in Massachusetts Middle Schools

    Loveless, Tom

    2009-01-01

    This study examines tracking--the practice of grouping students into separate classes or courses based on their prior academic achievement--at the middle-school level, and the percentage of high-achieving students in tracked and untracked schools. It focuses on Massachusetts, a leader in "reforming" tracking, and the changes that have occurred…

  7. Achievement Awards for High School Matriculation: Evidence from Randomized Trials

    Joshua Angrist; Victor Lavy

    2002-01-01

    In Israel, as in many other countries, a high school matriculation certificate is required by universities and some jobs. In spite of the certificate's value, Israeli society is marked by vast differences in matriculation rates by region and socioeconomic status. We attempted to increase the likelihood of matriculation among low-achieving students by offering substantial cash incentives in two demonstration programs. As a theoretical matter, cash incentives may be helpful if low-achieving stu...

  8. Exploring High-Achieving Students' Images of Mathematicians

    Aguilar, Mario Sánchez; Rosas, Alejandro; Zavaleta, Juan Gabriel Molina; Romo-Vázquez, Avenilde

    2016-01-01

    The aim of this study is to describe the images that a group of high-achieving Mexican students hold of mathematicians. For this investigation, we used a research method based on the Draw-A-Scientist Test (DAST) with a sample of 63 Mexican high school students. The group of students' pictorial and written descriptions of mathematicians assisted us…

  9. High School Employment and Academic Achievement: A Note for Educators

    Keister, Mary; Hall, Joshua

    2010-01-01

    Educators are often in a position to affect student decisions to work during the school term. This study reviews and summarizes the literature on the effect that employment during high school has on academic achievement. The available evidence suggests that part-time jobs for high school students are beneficial as long as the number of hours…

  10. Economic Evaluation of Irrigated Dairy Forage Production.

    Gaffy, Joe; Gyles, Oliver

    2003-01-01

    An optimisation model was developed to compare the profitability of different forage species on irrigated dairy farms. The model is driven by the energy and protein requirements of the milking cow. The objective of the model is to maximise income, after herd and feed costs, by selecting the area of the farm sown to particular forage species. Different forage species may require different animal production systems to optimise their profitability. In order to achieve this, the model can alter t...

  11. Productivity and carbon footprint of perennial grass-forage legume intercropping strategies with high or low nitrogen fertilizer input.

    Hauggaard-Nielsen, Henrik; Lachouani, Petra; Knudsen, Marie Trydeman; Ambus, Per; Boelt, Birte; Gislum, René

    2016-01-15

    A three-season field experiment was established and repeated twice with spring barley used as cover crop for different perennial grass-legume intercrops followed by a full year pasture cropping and winter wheat after sward incorporation. Two fertilization regimes were applied with plots fertilized with either a high or a low rate of mineral nitrogen (N) fertilizer. Life cycle assessment (LCA) was used to evaluate the carbon footprint (global warming potential) of the grassland management including measured nitrous oxide (N2O) emissions after sward incorporation. Without applying any mineral N fertilizer, the forage legume pure stand, especially red clover, was able to produce about 15 t above ground dry matter ha(-1) year(-1) saving around 325 kg mineral Nfertilizer ha(-1) compared to the cocksfoot and tall fescue grass treatments. The pure stand ryegrass yielded around 3t DM more than red clover in the high fertilizer treatment. Nitrous oxide emissions were highest in the treatments containing legumes. The LCA showed that the low input N systems had markedly lower carbon footprint values than crops from the high N input system with the pure stand legumes without N fertilization having the lowest carbon footprint. Thus, a reduction in N fertilizer application rates in the low input systems offsets increased N2O emissions after forage legume treatments compared to grass plots due to the N fertilizer production-related emissions. When including the subsequent wheat yield in the total aboveground production across the three-season rotation, the pure stand red clover without N application and pure stand ryegrass treatments with the highest N input equalled. The present study illustrate how leguminous biological nitrogen fixation (BNF) represents an important low impact renewable N source without reducing crop yields and thereby farmers earnings. PMID:26479907

  12. Forage density effect on sound insulation properties

    Green, Ole; Tortajada, Vicent Gassó; Gislum, René;

    2010-01-01

    One of the main parameters affecting forage management and quality is density. Existing methods used for measuring physical properties of forage involve costly destructive analysis. A frequent and appropriate control of the forage density is required for optimizing the management of silage, hay and...... forage density. The method has been used to analyse the correlation of the density with the sound insulation spectra produced by small-scale models of hay, silage and straw. Results show that the sound insulation spectra of forage have a high correlation with the density and a significant congruence with...

  13. Relationship between High School Leadership Team Practices and Student Achievement

    McInnis, Timothy M.

    2009-01-01

    This study investigated if a relationship existed between student achievement in 10th grade Missouri Assessment Program mathematics and 11th grade communication arts scores in 2007 and high school leadership team perceptions of the extent to which they demonstrated leadership practices. The secondary purpose was to compare perceptional…

  14. Student Achievement through the Development of Complete High School Culture

    Lamphere, Michael Frederick, Jr.

    2012-01-01

    This dissertation undertook an investigation of school culture and achievement in the high school setting. The national data set ELS:2002 was used as the pool of variables because it allows for a complete picture of school culture comprising students, parents, administrators, and teachers. The data were selected based on current literature and…

  15. Self-Esteem and Academic Achievement of High School Students

    Moradi Sheykhjan, Tohid; Jabari, Kamran; Rajeswari, K.

    2014-01-01

    The primary purpose of this study was to determine the influence of self-esteem on academic achievement among high school students in Miandoab City of Iran. The methodology of the research is descriptive and correlation that descriptive and inferential statistics were used to analyze the data. Statistical Society includes male and female high…

  16. Student Achievement Levels Climb at Ribault Senior High School.

    Profiles, Programs & Products, 1983

    1983-01-01

    Ribault (Florida) Senior High School has reported a dramatic increase in student achievement levels since implementing a comprehensive college preparation curriculum. Among the program changes that contributed to those gains are: (1) the establishment and consistent enforcement of a strong discipline program, including rules for student conduct, a…

  17. Best Practices for Achieving High, Rapid Reading Gains

    Carbo, Marie

    2008-01-01

    The percentage of students who read at the proficient level on the National Assessment of Educational Progress (NAEP) has not improved, and is appallingly low. In order for students to achieve high reading gains and become life-long readers, reading comprehension and reading enjoyment must be the top two goals. This article presents several…

  18. Having opposite gender friends can reduce high school achievement

    Hill, Andrew J.

    2015-01-01

    Is having a friend from the opposite gender a help or a hindrance to getting good grades in high school? In new research using data on high school friendship networks and academic achievement, Andrew J. Hill finds that a ten percent increase in opposite gender friends reduces a students’ GPA score by 0.1 points. He writes that this effect on students can be found in mathematics and science subjects, but not in English and history.

  19. Database - Student's Achievements in High School and Thereafter

    Branislav Oreskovic; Ana Hajdic; Marko Baotic

    2005-01-01

    Computer infrastructure represented in the Croatian educational system is rather developed nowadays. It would be necessary to develop an integral information system (IIS) within the competent Ministry (Ministry of Science, Education and Sports) for the purpose of more efficient and high-quality management of the educational process itself as well as process control. In this paper by the proposed database “Students’ achievements in high school and thereafter” we describe a possible model of da...

  20. Academic achievement of junior high school students with sleep disorders

    Fijri Auliyanti

    2016-07-01

    Full Text Available Background Sleep disorders are prevalent in adolescents and may influence their academic achievement. To date, no study has been done in Indonesia on academic achievement in students with sleep disorders and its related factors. Objective To assess for relationships between academic achievement and related factors, including gender, motivation and learning strategies, IQ level, maternal educational level, socioeconomic status, family structure, after-hours education program, presence of TV/computer in the bedroom, sleep duration during school days, as well as bedtime and wakeup time difference in junior high school students with sleep disorders. Methods This cross-sectional study was performed from January to March 2013. Subjects were students from five junior high schools in Jakarta who fulfilled the criteria for sleep disorders based on the Sleep Disturbance Scale for Children questionnaire. Results There were 111 study subjects. The prevalence of sleep disorders was 39.7%, mostly in difficulties initiating and maintaining sleep (70.2%. Below-average academic achievement was seen in 47.6% of subjects. Factors significantly related to below-average academic achievement were after-hours education program (prevalence ratio 5.6; 95%CI 1.36 to 23.18; P = 0.017, average IQ level (prevalence ratio 3.26; 95%CI 1.38 to 7.71; P = 0.007, and male gender (prevalence ratio 2.68; 95%CI 1.06 to 6.78; P = 0.037. Conclusion Among junior high school students with sleep disorders, factors related to below-average academic achievement are afterhours education program (more than 2 types, the average IQ level, and male gender.

  1. Academic achievement of junior high school students with sleep disorders

    Fijri Auliyanti

    2015-01-01

    Full Text Available Background Sleep disorders are prevalent in adolescents and may influence their academic achievement. To date, no study has been done in Indonesia on academic achievement in students with sleep disorders and its related factors. Objective To assess for relationships between academic achievement and related factors, including gender, motivation and learning strategies, IQ level, maternal educational level, socioeconomic status, family structure, after-hours education program, presence of TV/computer in the bedroom, sleep duration during school days, as well as bedtime and wakeup time difference in junior high school students with sleep disorders. Methods This cross-sectional study was performed from January to March 2013. Subjects were students from five junior high schools in Jakarta who fulfilled the criteria for sleep disorders based on the Sleep Disturbance Scale for Children questionnaire. Results There were 111 study subjects. The prevalence of sleep disorders was 39.7%, mostly in difficulties initiating and maintaining sleep (70.2%. Below-average academic achievement was seen in 47.6% of subjects. Factors significantly related to below-average academic achievement were after-hours education program (prevalence ratio 5.6; 95%CI 1.36 to 23.18; P = 0.017, average IQ level (prevalence ratio 3.26; 95%CI 1.38 to 7.71; P = 0.007, and male gender (prevalence ratio 2.68; 95%CI 1.06 to 6.78; P = 0.037. Conclusion Among junior high school students with sleep disorders, factors related to below-average academic achievement are after-hours education program (more than 2 types, the average IQ level, and male gender. [Paediatr Indones. 2015;55:50-8.].

  2. A SELF PROCESS IMPROVEMENT FOR ACHIEVING HIGH SOFTWARE QUALITY

    DR. SHASHANK.D.JOSHI

    2011-05-01

    Full Text Available Quality has been one of the most important factors in judging any product. Quality means “a degree or grade of excellence or worth”. Quality is a term that is usually described using adjectives. Quality has several attributes to it, some of which can be quantified using metrics. These attributes such as usability, portability, security, performance, reliability etc have different importance in different projects. Different software quality assurance methods & practices have been used in different software projects to attain the true value. Quality is an attribute which is a distinct feature and it differs with people’s perception. Achieving high software quality involves measurement of software metrics and optimization based on estimated values. As the software systems grow larger, complexity ofdesign and implementation increases, and this in turn is more prone to defects and hence directly affect the quality of the systems. However, in any software project, high quality is always desirable, and many projects have specific quality requirements. Achieving high software quality involves measurement of software metrics and optimization based on estimated values. Developing high quality software is governed by factors such as people, process, technology and cost. This paper attempts to present a novel approach towards achieving high software quality in various kinds of projects under given constraints.

  3. Parent Involvement Practices of High-Achieving Elementary Science Students

    Waller, Samara Susan

    This study addressed a prevalence of low achievement in science courses in an urban school district in Georgia. National leaders and educators have identified the improvement of science proficiency as critical to the future of American industry. The purpose of this study was to examine parent involvement in this school district and its contribution to the academic achievement of successful science students. Social capital theory guided this study by suggesting that students achieve best when investments are made into their academic and social development. A collective case study qualitative research design was used to interview 9 parent participants at 2 elementary schools whose children scored in the exceeds category on the Science CRCT. The research questions focused on what these parents did at home to support their children's academic achievement. Data were collected using a semi-structured interview protocol and analyzed through the categorical aggregation of transcribed interviews. Key findings revealed that the parents invested time and resources in 3 practices: communicating high expectations, supporting and developing key skills, and communicating with teachers. These findings contribute to social change at both the local and community level by creating a starting point for teachers, principals, and district leaders to reexamine the value of parent input in the educational process, and by providing data to support the revision of current parent involvement policies. Possibilities for further study building upon the findings of this study may focus on student perceptions of their parents' parenting as it relates to their science achievement.

  4. "Rigorous Courses" and Student Achievement in High School

    Shireman, Robert

    2004-01-01

    Holding schools accountable for student achievement can only work if the goals are clear. California's school standards are well-regarded nationally for their clarity and their rigor, but it is not clear what courses students are expected to take beyond the minimum graduation requirements. The paper discusses the relatively successful efforts to encourage students to take higher-level courses in high school in two states, Indiana and Texas; it outlines potential stumbling blocks in these effo...

  5. Unlocking Emergent Talent: Supporting High Achievement of Low-Income, High Ability Students

    Olszewski-Kubilius, Paula; Clarenbach, Jane

    2012-01-01

    This report takes a comprehensive look at achievement for low-income promising learners--past, present, and future. At its core, it challenges the nation to move beyond its near-singular focus of achieving minimum performance for all students, to identifying and developing the talent of all students who are capable of high achievement, including…

  6. Factors affecting forage stand establishment

    Sulc R.M.

    1998-01-01

    Full Text Available Significant advances have been made in our knowledge of forage seed physiology, technology, and stand establishment practices; however, stand establishment continues to be one of the most common production problems affecting forage crops in the USA. There is a need for research on stand establishment of forage crops under abiotic and biotic stress. Although the forage seed industry produces and markets seed of high quality, new methods of assessing seed vigor are needed and their use should be expanded in the industry to enable matching seed lot performance to specific environmental conditions where performance can be maximized. Seed treatment and seed coating are used in the forage seed industry, and studies have shown they are of benefit in some environments. There is an increase in no-tillage seeding of forage crops, but improvements in the no-tillage planting equipment are needed to make them better suited to small seeds. Other recent developments in seeding techniques include broadcasting seed with dry granular and fluid fertilizers, which improves the efficiency of the seeding operation.

  7. Fishing amplifies forage fish population collapses

    Essington, Timothy E.; Moriarty, Pamela E.; Froehlich, Halley E.; Hodgson, Emma E.; Koehn, Laura E.; Oken, Kiva L.; Siple, Margaret C.; Stawitz, Christine C.

    2015-01-01

    Forage fish provide substantial benefits to both humans and ocean food webs, but these benefits may be in conflict unless there are effective policies governing human activities, such as fishing. Collapses of forage fish induce widespread ecological effects on dependent predators, but attributing collapses to fishing has been difficult because of natural fluctuations of these stocks. We implicate fishing in forage fish stock collapses by showing that high fishing rates are maintained when sto...

  8. Mindmapping: Its effects on student achievement in high school biology

    Cunningham, Glennis Edge

    The primary goal of schools is to promote the highest degree of learning possible. Yet teachers spend the majority of their time engaged in lecturing while students spend the majority of their time passively present (Cawelti, 1997, Grinder, 1991; Jackson & Davis, 2000; Jenkins, 1996). Helping students develop proficiency in learning, which translates into using that expertise to construct knowledge in subject domains, is a crucial goal of education. Students need exposure to teaching and learning practices that prepare them for both the classroom and their places in the future workforce (Ettinger, 1998; Longley, Goodchild, Maguire, & Rhind, 2001; NRC, 1996; Texley & Wild, 1996). The purpose of this study was to determine if achievement in high school science courses could be enhanced utilizing mindmapping. The subjects were primarily 9th and 10th graders (n = 147) at a suburban South Texas high school. A pretest-posttest control group design was selected to determine the effects of mindmapping on student achievement as measured by a teacher-developed, panel-validated instrument. Follow-up interviews were conducted with the teacher and a purposive sample of students (n = 7) to determine their perceptions of mindmapping and its effects on teaching and learning. Mindmapping is a strategy for visually displaying large amounts of conceptual, hierarchical information in a concise, organized, and accessible format. Mindmaps arrange information similar to that found on the traditional topic outline into colorful spatial displays that offer the user a view of the "forest" as well as the "trees" (Hyerle, 1996; Wandersee, 1990b). An independent samples t-test and a one-way analysis of covariance (ANCOVA) determined no significant difference in achievement between the groups. The experimental group improved in achievement at least as much as the control group. Several factors may have played a role in the lack of statistically significant results. These factors include the

  9. Assessing the Effects of Grassland Management on Forage Production and Environmental Quality to Identify Paths to Ecological Intensification in Mountain Grasslands

    Loucougaray, Grégory; Dobremez, Laurent; Gos, Pierre; Pauthenet, Yves; Nettier, Baptiste; Lavorel, Sandra

    2015-11-01

    Ecological intensification in grasslands can be regarded as a process for increasing forage production while maintaining high levels of ecosystem functions and biodiversity. In the mountain Vercors massif, where dairy cattle farming is the main component of agriculture, how to achieve forage autonomy at farm level while sustaining environmental quality for tourism and local dairy products has recently stimulated local debate. As specific management is one of the main drivers of ecosystem functioning, we assessed the response of forage production and environmental quality at grassland scale across a wide range of management practices. We aimed to determine which components of management can be harnessed to better match forage production and environmental quality. We sampled the vegetation of 51 grasslands stratified across 13 grassland types. We assessed each grassland for agronomic and environmental properties, measuring forage production, forage quality, and indices based on the abundance of particular plant species such as timing flexibility, apiarian potential, and aromatic plants. Our results revealed an expected trade-off between forage production and environmental quality, notably by stressing the contrasts between sown and permanent grasslands. However, strong within-type variability in both production and environmental quality as well as in flexibility of timing of use suggests possible ways to improve this trade-off at grassland and farm scales. As achieving forage autonomy relies on increasing both forage production and grassland resilience, our results highlight the critical role of the ratio between sown and permanent grasslands as a major path for ecological intensification in mountain grasslands.

  10. Honeybee economics: optimisation of foraging in a variable world

    Stabentheiner, Anton; Kovac, Helmut

    2016-01-01

    In honeybees fast and efficient exploitation of nectar and pollen sources is achieved by persistent endothermy throughout the foraging cycle, which means extremely high energy costs. The need for food promotes maximisation of the intake rate, and the high costs call for energetic optimisation. Experiments on how honeybees resolve this conflict have to consider that foraging takes place in a variable environment concerning microclimate and food quality and availability. Here we report, in simultaneous measurements of energy costs, gains, and intake rate and efficiency, how honeybee foragers manage this challenge in their highly variable environment. If possible, during unlimited sucrose flow, they follow an ‘investment-guided’ (‘time is honey’) economic strategy promising increased returns. They maximise net intake rate by investing both own heat production and solar heat to increase body temperature to a level which guarantees a high suction velocity. They switch to an ‘economizing’ (‘save the honey’) optimisation of energetic efficiency if the intake rate is restricted by the food source when an increased body temperature would not guarantee a high intake rate. With this flexible and graded change between economic strategies honeybees can do both maximise colony intake rate and optimise foraging efficiency in reaction to environmental variation. PMID:27320240

  11. Honeybee economics: optimisation of foraging in a variable world.

    Stabentheiner, Anton; Kovac, Helmut

    2016-01-01

    In honeybees fast and efficient exploitation of nectar and pollen sources is achieved by persistent endothermy throughout the foraging cycle, which means extremely high energy costs. The need for food promotes maximisation of the intake rate, and the high costs call for energetic optimisation. Experiments on how honeybees resolve this conflict have to consider that foraging takes place in a variable environment concerning microclimate and food quality and availability. Here we report, in simultaneous measurements of energy costs, gains, and intake rate and efficiency, how honeybee foragers manage this challenge in their highly variable environment. If possible, during unlimited sucrose flow, they follow an 'investment-guided' ('time is honey') economic strategy promising increased returns. They maximise net intake rate by investing both own heat production and solar heat to increase body temperature to a level which guarantees a high suction velocity. They switch to an 'economizing' ('save the honey') optimisation of energetic efficiency if the intake rate is restricted by the food source when an increased body temperature would not guarantee a high intake rate. With this flexible and graded change between economic strategies honeybees can do both maximise colony intake rate and optimise foraging efficiency in reaction to environmental variation. PMID:27320240

  12. Achieving High Resolution Timer Events in Virtualized Environment.

    Adamczyk, Blazej; Chydzinski, Andrzej

    2015-01-01

    Virtual Machine Monitors (VMM) have become popular in different application areas. Some applications may require to generate the timer events with high resolution and precision. This however may be challenging due to the complexity of VMMs. In this paper we focus on the timer functionality provided by five different VMMs-Xen, KVM, Qemu, VirtualBox and VMWare. Firstly, we evaluate resolutions and precisions of their timer events. Apparently, provided resolutions and precisions are far too low for some applications (e.g. networking applications with the quality of service). Then, using Xen virtualization we demonstrate the improved timer design that greatly enhances both the resolution and precision of achieved timer events. PMID:26177366

  13. Computer Security: SAHARA - Security As High As Reasonably Achievable

    Stefan Lueders, Computer Security Team

    2015-01-01

    History has shown us time and again that our computer systems, computing services and control systems have digital security deficiencies. Too often we deploy stop-gap solutions and improvised hacks, or we just accept that it is too late to change things.    In my opinion, this blatantly contradicts the professionalism we show in our daily work. Other priorities and time pressure force us to ignore security or to consider it too late to do anything… but we can do better. Just look at how “safety” is dealt with at CERN! “ALARA” (As Low As Reasonably Achievable) is the objective set by the CERN HSE group when considering our individual radiological exposure. Following this paradigm, and shifting it from CERN safety to CERN computer security, would give us “SAHARA”: “Security As High As Reasonably Achievable”. In other words, all possible computer security measures must be applied, so long as ...

  14. Achieving ultra-high temperatures with a resistive emitter array

    Danielson, Tom; Franks, Greg; Holmes, Nicholas; LaVeigne, Joe; Matis, Greg; McHugh, Steve; Norton, Dennis; Vengel, Tony; Lannon, John; Goodwin, Scott

    2016-05-01

    The rapid development of very-large format infrared detector arrays has challenged the IR scene projector community to also develop larger-format infrared emitter arrays to support the testing of systems incorporating these detectors. In addition to larger formats, many scene projector users require much higher simulated temperatures than can be generated with current technology in order to fully evaluate the performance of their systems and associated processing algorithms. Under the Ultra High Temperature (UHT) development program, Santa Barbara Infrared Inc. (SBIR) is developing a new infrared scene projector architecture capable of producing both very large format (>1024 x 1024) resistive emitter arrays and improved emitter pixel technology capable of simulating very high apparent temperatures. During earlier phases of the program, SBIR demonstrated materials with MWIR apparent temperatures in excess of 1400 K. New emitter materials have subsequently been selected to produce pixels that achieve even higher apparent temperatures. Test results from pixels fabricated using the new material set will be presented and discussed. A 'scalable' Read In Integrated Circuit (RIIC) is also being developed under the same UHT program to drive the high temperature pixels. This RIIC will utilize through-silicon via (TSV) and Quilt Packaging (QP) technologies to allow seamless tiling of multiple chips to fabricate very large arrays, and thus overcome the yield limitations inherent in large-scale integrated circuits. Results of design verification testing of the completed RIIC will be presented and discussed.

  15. Nutritional Evaluation of Non Forage High Fibrous Tropical Feeds for Ruminant Using In Vitro Gas Production Technique

    Songsak CHUMPAWADEE

    2005-06-01

    Full Text Available Six non forage high fibrous tropical feedstuffs were used to evaluate their nutritive value using an in vitro gas production technique. The rumen mixed microbe inoculums were taken from 2fistulated Brahman-Thai native crossbred steers. The treatments were 1 palm meal (mech-extd, 2 palm meal (solv-extd, 3 leucaena meal (leaf and stem, 4 coconut meal (mech-extd, 5 mung bean meal and 6 dried brewers grain. The treatments were assigned to a completely randomized design. The results indicated that the soluble gas fraction (a; -7.91, -24.06, -2.11, -28.96, -10.31 and -4.35 ml, respectively, fermentation of the insoluble fraction (b; 99.33, 124.06, 70.90, 128.96, 110.31 and 99.33 ml, respectively, rate of gas production (c; 0.054, 0.071, 0.047, 0.122, 0.050 and 0.045 %/h, respectively and potential extent of gas production (a+b; 107.26, 148.13, 73.02, 157.93, 120.62 and 103.82 ml, respectively were significantly different (P < 0.01 among treatments. The cumulative gas volume at 24, 48 and 96 h after incubation were significantly different (P < 0.01. These results suggested that coconut meal (mech-extd, palm meal (solv-extd, mung bean meal, palm meal (mech-extd and dried brewer grain exhibit high fermentability in the rumen while luecaena meal has the lowest value.

  16. Heat Damaged Forages: Effects on Forage Quality

    Traditionally, heat damage in forages has been associated with alterations in forage protein quality as a result of Maillard reactions, and most producers and nutritionists are familiar with this concept. However, this is not necessarily the most important negative consequence of spontaneous heating...

  17. Application Of Stable Isotope Analysis To Study Temporal Changes In Foraging Ecology In A Highly Endangered Amphibian

    Gillespie, J. Hayley

    2013-01-01

    Background Understanding dietary trends for endangered species may be essential to assessing the effects of ecological disturbances such as habitat modification, species introductions or global climate change. Documenting temporal variation in prey selection may also be crucial for understanding population dynamics. However, the rarity, secretive behaviours and obscure microhabitats of some endangered species can make direct foraging observations difficult or impossible. Furthermore, the leth...

  18. Shallow food for deep divers: Dynamic foraging behavior of male sperm whales in a high latitude habitat

    Teloni, Valeria; Johnson, M.P.; Miller, P.J.O.;

    2008-01-01

    218 m and the last usual click at depths ranging between 1 and 1114 m. Echolocation buzzes, which are used as an indication of prey capture attempts, were emitted at depths between 17 and 1860 m, during both the descent and ascent phase of deep dives. The foraging behavior varied markedly with depth...

  19. Winter distribution and use of high elevation caves as foraging sites by the endangered Hawaiian hoary bat, Lasiurus cinereus semotus

    Bonaccorso, Frank; Montoya-Aiona, Kristina; Pinzari, Corinna A.; Todd, Christopher M.

    2016-01-01

    We examine altitudinal movements involving unusual use of caves by Hawaiian hoary bats, Lasiurus cinereus semotus, during winter and spring in the Mauna Loa Forest Reserve (MLFR), Hawai‘i Island. Acoustic detection of hoary bat vocalizations, were recorded with regularity outside 13 lava tube cave entrances situated between 2,200 to 3,600 m asl from November 2012 to April 2013. Vocalizations were most numerous in November and December with the number of call events and echolocation pulses decreasing through the following months. Bat activity was positively correlated with air temperature and negatively correlated with wind speed. Visual searches found no evidence of hibernacula nor do Hawaiian hoary bats appear to shelter by day in these caves. Nevertheless, bats fly deep into caves as evidenced by numerous carcasses found in cave interiors. The occurrence of feeding buzzes around cave entrances and visual observations of bats flying in acrobatic fashion in cave interiors point to the use of these spaces as foraging sites. Peridroma moth species (Noctuidae), the only abundant nocturnal, flying insect sheltering in large numbers in rock rubble and on cave walls in the MLFR, apparently serve as the principal prey attracting hoary bats during winter to lava tube caves in the upper MLFR. Caves above 3,000 m on Mauna Loa harbor temperatures suitable for Pseudogymnoascus destructansfungi, the causative agent of White-nose Syndrome that is highly lethal to some species of North American cave-dwelling bats. We discuss the potential for White-nose Syndrome to establish and affect Hawaiian hoary bats.

  20. High-Achieving High School Students and Not so High-Achieving College Students: A Look at Lack of Self-Control, Academic Ability, and Performance in College

    Honken, Nora B.; Ralston, Patricia A. S.

    2013-01-01

    This study investigated the relationship among lack of self-control, academic ability, and academic performance for a cohort of freshman engineering students who were, with a few exceptions, extremely high achievers in high school. Structural equation modeling analysis led to the conclusion that lack of self-control in high school, as measured by…

  1. Does Recreational Computer Use Affect High School Achievement?

    Bowers, Alex J.; Berland, Matthew

    2013-01-01

    Historically, the relationship between student academic achievement and use of computers for fun and video gaming has been described from a multitude of perspectives, from positive, to negative, to neutral. However, recent research has indicated that computer use and video gaming may be positively associated with achievement, yet these studies…

  2. Learning Styles and High School Students' Chemistry Achievement

    Uzuntiryaki, Esen

    2007-01-01

    The aim of the present study was to investigate the effects of students' learning styles on their chemistry achievement, and whether matching between teaching and learning styles also affects students' chemistry achievement. Two hundred and sixty-five tenth-grade students enrolled in a chemistry course and seven chemistry teachers participated in…

  3. Preferences of High Achieving High School Students in Their Career Development

    Kim, Mihyeon

    2010-01-01

    The intent of this study was to identify the needs and preference of high-achieving high school students. In terms of career related programs in high school, students listed AP courses and mentoring as their preferred career-related programs. Also, students stated that career guidance by counselors, workshops or sessions, and tech prep were the…

  4. Potency Of Clitoria Ternatea As Forage For Livestock

    Endang Sutedi

    2013-01-01

    Availability of forage is one of the factors determining the success of ruminant livestock production, especially during drought that resulting in poor livestock condition. Forage legume is an important group of forage plants, containing high nutritive value. One of the legume plants which potential as ruminant feed is Clitoria ternatea. This plant can grow well in all types of soil and dry conditions, also produces seed continously. The production of forage was 25-29 ton DM/ha with seed prod...

  5. Productivity and carbon footprint of perennial grass-forage legume intercropping strategies with high or low nitrogen fertilizer input

    Hauggaard-Nielsen, Henrik; Lachouani, Petra; Knudsen, Marie Trydeman;

    2016-01-01

    A three-season field experiment was established and repeated twice with spring barley used as cover crop for different perennial grass-legume intercrops followed by a full year pasture cropping and winter wheat after sward incorporation. Two fertilization regimes were applied with plots fertilized...... fertilizer, the forage legume pure stand, especially red clover, was able to produce about 15 t aboveground dry matter ha− 1 year− 1 saving around 325 kg mineral N fertilizer ha− 1 compared to the cocksfoot and tall fescue grass treatments. The pure stand ryegrass yielded around 3 t DM more than red clover...... lowest carbon footprint. Thus, a reduction in N fertilizer application rates in the low input systems offsets increased N2O emissions after forage legume treatments compared to grass plots due to the N fertilizer production-related emissions. When including the subsequent wheat yield in the total...

  6. Absence of vancomycin-resistant enterococci among highly ESBL-positive crows (Corvus splendens) foraging on hospital waste in Bangladesh

    Hasan, Badrul; Järhult, Josef D.

    2015-01-01

    Background: Vancomycin-resistant enterococci (VRE) have emerged as a growing problem in hospitals; however, domesticated animals, poultry, and wild birds are acting as potential reservoirs. There is a knowledge gap in the Epidemiology of VRE from Bangladesh.Methods: To study the prevalence of VRE and the mechanisms of resistance implicated among wild birds, 238 fecal samples were collected in 2010 from house crows (Corvus splendens) foraging on hospital waste in Bangladesh. Fecal samples were...

  7. Adaptive Bacterial Foraging Optimization Algorithm Based on Social Foraging Strategy

    Hai Shen; Yunlong Zhu

    2014-01-01

    In 2002, K. M. Passino proposed Bacterial Foraging Optimization Algorithm (BFOA) for distributed optimization and control. Biologic foraging strategies are diverse. Based on social and intelligent foraging theory, this paper proposed an adaptive bacterial foraging optimization algorithm, and introduced six foraging operators: chaos run operator, assimilation run operator, tumble operator, swimming operator, reproduction operator and elimination-dispersal operator. Among those operators, chaos...

  8. Academic attainment and the high school science experiences among high-achieving African American males

    Trice, Rodney Nathaniel

    This study examines the educational experiences of high achieving African American males. More specifically, it analyzes the influences on their successful navigation through high school science. Through a series of interviews, observations, questionnaires, science portfolios, and review of existing data the researcher attempted to obtain a deeper understanding of high achieving African American males and their limitations to academic attainment and high school science experiences. The investigation is limited to ten high achieving African American male science students at Woodcrest High School. Woodcrest is situated at the cross section of a suburban and rural community located in the southeastern section of the United States. Although this investigation involves African American males, all of whom are successful in school, its findings should not be generalized to this nor any other group of students. The research question that guided this study is: What are the limitations to academic attainment and the high school science experiences of high achieving African American males? The student participants expose how suspension and expulsion, special education placement, academic tracking, science instruction, and teacher expectation influence academic achievement. The role parents play, student self-concept, peer relationships, and student learning styles are also analyzed. The anthology of data rendered three overarching themes: (1) unequal access to education, (2) maintenance of unfair educational structures, and (3) authentic characterizations of African American males. Often the policies and practices set in place by school officials aid in creating hurdles to academic achievement. These policies and practices are often formed without meaningful consideration of the unintended consequences that may affect different student populations, particularly the most vulnerable. The findings from this study expose that high achieving African American males face major

  9. Sampling requirements for forage quality characterization of rectangular hay bales

    Sheaffer, C.C.; Martin, N.P.; Jewett, J.G.; Halgerson, J.; Moon, R.D.; Cuomo, G.R.

    2000-02-01

    Commercial lots of alfalfa (Medicago sativa L.) hay are often bought and sold on the basis of forage quality. Proper sampling is essential to obtain accurate forage quality results for pricing of alfalfa hay, but information about sampling is limited to small, 20- to 40-kg rectangular bales. Their objectives were to determine the within-bale variation in 400-kg rectangular bales and to determine the number and distribution of core samples required to represent the crude protein (CP), acid detergent fiber (ADF), neutral detergent fiber (NDF), and dry matter (DM) concentration in commercial lots of alfalfa hay. Four bales were selected from each of three hay lots and core sampled nine times per side for a total of 54 cores per bale. There was no consistent pattern of forage quality variation within bales. Averaged across lots, any portion of a bale was highly correlated with bale grand means for CP, ADF, NDF, and DM. Three lots of hay were probed six times per bale, one core per bale side from 55, 14, and 14 bales per lot. For determination of CP, ADF, NDF, and DM concentration, total core numbers required to achieve an acceptable standard error (SE) were minimized by sampling once per bale. Bootstrap analysis of data from the most variable hay lot suggested that forage quality of any lot of 400-kg alfalfa hay bales should be adequately represented by 12 bales sampled once per bale.

  10. Parenting Style, Perfectionism, and Creativity in High-Ability and High-Achieving Young Adults

    Miller, Angie L.; Lambert, Amber D.; Speirs Neumeister, Kristie L.

    2012-01-01

    The current study explores the potential relationships among perceived parenting style, perfectionism, and creativity in a high-ability and high-achieving young adult population. Using data from 323 honors college students at a Midwestern university, bivariate correlations suggested positive relationships between (a) permissive parenting style and…

  11. Success Despite Socioeconomics: A Case Study of a High-Achieving, High-Poverty School

    Tilley, Thomas Brent; Smith, Samuel J.; Claxton, Russell L.

    2012-01-01

    This case study of a high-achieving, high-poverty school describes the school's leadership, culture, and programs that contributed to its success. Data were collected from two surveys (the School Culture Survey and the Vanderbilt Assessment of Leadership in Education), observations at the school site, and interviews with school personnel. The…

  12. Utilisation of intensive foraging zones by female Australian fur seals.

    Andrew J Hoskins

    Full Text Available Within a heterogeneous environment, animals must efficiently locate and utilise foraging patches. One way animals can achieve this is by increasing residency times in areas where foraging success is highest (area-restricted search. For air-breathing diving predators, increased patch residency times can be achieved by altering both surface movements and diving patterns. The current study aimed to spatially identify the areas where female Australian fur seals allocated the most foraging effort, while simultaneously determining the behavioural changes that occur when they increase their foraging intensity. To achieve this, foraging behaviour was successfully recorded with a FastLoc GPS logger and dive behaviour recorder from 29 individual females provisioning pups. Females travelled an average of 118 ± 50 km from their colony during foraging trips that lasted 7.3 ± 3.4 days. Comparison of two methods for calculating foraging intensity (first-passage time and first-passage time modified to include diving behaviour determined that, due to extended surface intervals where individuals did not travel, inclusion of diving behaviour into foraging analyses was important for this species. Foraging intensity 'hot spots' were found to exist in a mosaic of patches within the Bass Basin, primarily to the south-west of the colony. However, the composition of benthic habitat being targeted remains unclear. When increasing their foraging intensity, individuals tended to perform dives around 148 s or greater, with descent/ascent rates of approximately 1.9 m•s-1 or greater and reduced postdive durations. This suggests individuals were maximising their time within the benthic foraging zone. Furthermore, individuals increased tortuosity and decreased travel speeds while at the surface to maximise their time within a foraging location. These results suggest Australian fur seals will modify both surface movements and diving behaviour to maximise their time within a

  13. Achieving Timeliness and High Throughput Metrics in Dissemination Systems

    MANNE ANUSHA

    2012-09-01

    Full Text Available Existing systems for information dissemination is inadequate and typically results in information gaps. The lack of a clear concise system for information dissemination makes it difficult to determine the most efficient and effective way to pass information especially in the fields of ecommerce and security alerting systems to the appropriate parties. These systems usually require that the desired information be matched between numerous sources and sinks based on established subscriptions. Timeliness and Throughput are performance metrics used for evaluation. And these existing systems fail to achieve a balance between the two. So a much better system termed INFOD (INFOrmation Dissemination was proposed earlier that achieves a balance between performance metrics. We observed that an Integrated Control Loop used by admission control scheme of INFOD employs PL/SQL stored procedures that are huge computation overhead. We propose to replace them with Java stored procedures that can tremendously increase the performance.

  14. Ruminal Fermentation of Anti-Methanogenic Nitrate- and Nitro-Containing Forages In Vitro

    Anderson, Robin C.; Ripley, Laura H.; Bowman, Jan G. P.; Callaway, Todd R.; Genovese, Kenneth J.; Beier, Ross C.; Harvey, Roger B.; Nisbet, David J.

    2016-01-01

    Nitrate, 3-nitro-1-propionic acid (NPA) and 3-nitro-1-propanol (NPOH) can accumulate in forages and be poisonous to animals if consumed in high enough amounts. These chemicals are also recognized as potent anti-methanogenic compounds, but plants naturally containing these chemicals have been studied little in this regard. Presently, we found that nitrate-, NPA-, or NPOH-containing forages effectively decreased methane production, by 35–87%, during in vitro fermentation by mixed cultures of ruminal microbes compared to fermentation by cultures incubated similarly with alfalfa. Methane production was further decreased during the incubation of mixed cultures also inoculated with Denitrobacterium detoxificans, a ruminal bacterium known to metabolize nitrate, NPA, and NPOH. Inhibition of methanogens within the mixed cultures was greatest with the NPA- and NPOH-containing forages. Hydrogen accumulated in all the mixed cultures incubated with forages containing nitrate, NPA or NPOH and was dramatically higher, exceeding 40 μmol hydrogen/mL, in mixed cultures incubated with NPA-containing forage but not inoculated with D. detoxificans. This possibly reflects the inhibition of hydrogenase-catalyzed uptake of hydrogen produced via conversion of 50 μmol added formate per milliliter to hydrogen. Accumulations of volatile fatty acids revealed compensatory changes in fermentation in mixed cultures incubated with the nitrate-, NPA-, and NPOH-containing forages as evidenced by lower accumulations of acetate, and in some cases, higher accumulations of butyrate and lower accumulations of ammonia, iso-buytrate, and iso-valerate compared to cultures incubated with alfalfa. Results reveal that nitrate, NPA, and NPOH that accumulate naturally in forages can be made available within ruminal incubations to inhibit methanogenesis. Further research is warranted to determine if diets can be formulated with nitrate-, NPA-, and NPOH-containing forages to achieve efficacious mitigation

  15. Ruminal Fermentation of Anti-Methanogenic Nitrate- and Nitro-Containing Forages In Vitro.

    Anderson, Robin C; Ripley, Laura H; Bowman, Jan G P; Callaway, Todd R; Genovese, Kenneth J; Beier, Ross C; Harvey, Roger B; Nisbet, David J

    2016-01-01

    Nitrate, 3-nitro-1-propionic acid (NPA) and 3-nitro-1-propanol (NPOH) can accumulate in forages and be poisonous to animals if consumed in high enough amounts. These chemicals are also recognized as potent anti-methanogenic compounds, but plants naturally containing these chemicals have been studied little in this regard. Presently, we found that nitrate-, NPA-, or NPOH-containing forages effectively decreased methane production, by 35-87%, during in vitro fermentation by mixed cultures of ruminal microbes compared to fermentation by cultures incubated similarly with alfalfa. Methane production was further decreased during the incubation of mixed cultures also inoculated with Denitrobacterium detoxificans, a ruminal bacterium known to metabolize nitrate, NPA, and NPOH. Inhibition of methanogens within the mixed cultures was greatest with the NPA- and NPOH-containing forages. Hydrogen accumulated in all the mixed cultures incubated with forages containing nitrate, NPA or NPOH and was dramatically higher, exceeding 40 μmol hydrogen/mL, in mixed cultures incubated with NPA-containing forage but not inoculated with D. detoxificans. This possibly reflects the inhibition of hydrogenase-catalyzed uptake of hydrogen produced via conversion of 50 μmol added formate per milliliter to hydrogen. Accumulations of volatile fatty acids revealed compensatory changes in fermentation in mixed cultures incubated with the nitrate-, NPA-, and NPOH-containing forages as evidenced by lower accumulations of acetate, and in some cases, higher accumulations of butyrate and lower accumulations of ammonia, iso-buytrate, and iso-valerate compared to cultures incubated with alfalfa. Results reveal that nitrate, NPA, and NPOH that accumulate naturally in forages can be made available within ruminal incubations to inhibit methanogenesis. Further research is warranted to determine if diets can be formulated with nitrate-, NPA-, and NPOH-containing forages to achieve efficacious mitigation in

  16. EFFECTS OF FORAGE SPECIES ON RIB COMPOSITION, COLOR, AND PALATABILITY IN FORAGE-FINISHED BEEF

    Forty-seven Angus-crossbred steers were used to evaluate the effects of forage species grazed in the last 41 d of the finishing period on rib composition, color, and palatability in forage-finished beef and compared to traditional high concentrate finished. Steers grazed naturalized pastures (bluegr...

  17. “CORRELATES OF ACADEMIC ACHIEVEMENT OF HIGH ACHIEVERS OF HIGH SCHOOL STUDENTS AND THEIR HEALTH STATUS”.

    Anand K

    2015-01-01

    Many accounts have been given on the relationship between health variables and academic achievement of school students. Many studies have reported significant findings between school performance scores and health status indicators. The academic performance and of children with good health status were significantly higher than those of children with poor nutritional or health status as a whole. It is useful to have a general sense of conditions, potentially, important for school age childre...

  18. Relationships among Stress, Coping, and Mental Health in High-Achieving High School Students

    Suldo, Shannon M.; Shaunessy, Elizabeth; Hardesty, Robin

    2008-01-01

    This study investigates the relationships among stress, coping, and mental health in 139 students participating in an International Baccalaureate (IB) high school diploma program. Mental health was assessed using both positive indicators (life satisfaction, academic achievement, academic self-efficacy) and negative indicators (psychopathology) of…

  19. Practically Perfect in Every Way: Can Reframing Perfectionism for High-Achieving Undergraduates Impact Academic Resilience?

    Dickinson, Mary J.; Dickinson, David A. G.

    2015-01-01

    This study focuses on a pan-disciplinary scheme that targeted high-achieving undergraduate students. Earlier research from the scheme argued that high achievers have discernibly different learning and personal development support needs. One of the most frequent self-reported challenges within this high-achieving group is perfectionism. This…

  20. Absence of vancomycin-resistant enterococci among highly ESBL-positive crows (Corvus splendens foraging on hospital waste in Bangladesh

    Badrul Hasan

    2015-12-01

    Full Text Available Background: Vancomycin-resistant enterococci (VRE have emerged as a growing problem in hospitals; however, domesticated animals, poultry, and wild birds are acting as potential reservoirs. There is a knowledge gap in the Epidemiology of VRE from Bangladesh. Methods: To study the prevalence of VRE and the mechanisms of resistance implicated among wild birds, 238 fecal samples were collected in 2010 from house crows (Corvus splendens foraging on hospital waste in Bangladesh. Fecal samples were screened by analyzing color change in broth and screening for vanA and vanB resistant genes by PCR. Results: Neither vanA nor vanB genes were detected from the fecal samples. The house crow does not seem to constitute a reservoir for VRE. Conclusion: The zero prevalence is an indication that foraging on hospital waste does not constitute a major risk of VRE carriage in house crows and this is the first study to focus on the prevalence of VRE from wild birds in Bangladesh.

  1. Perception of dimethyl sulfide (DMS) by loggerhead sea turtles: a possible mechanism for locating high-productivity oceanic regions for foraging.

    Endres, Courtney S; Lohmann, Kenneth J

    2012-10-15

    During their long-distance migrations, sea turtles of several species feed on jellyfish and other invertebrates that are particularly abundant in ocean regions characterized by high productivity. An ability to distinguish productive oceanic regions from other areas, and to concentrate foraging activities in locations where prey density is highest, might therefore be adaptive. The volatile compound dimethyl sulfide (DMS) accumulates in the air above productive ocean areas such as upwelling and frontal zones. In principle, DMS might therefore serve as an indicator of high prey density for turtles. To determine whether turtles perceive DMS, juvenile loggerhead sea turtles (Caretta caretta) were placed into a water-filled arena in which DMS and other odorants could be introduced to the air above the water surface. Turtles exposed to air that had passed over a cup containing 10 nmol l(-1) DMS spent more time at the surface with their noses out of the water than control turtles, which were exposed to air that had passed over a cup containing distilled water. Odors that do not occur in the sea (cinnamon, jasmine and lemon) did not elicit increased surface time, implying that the response to DMS is unlikely to reflect a generalized response to any novel odor. The results demonstrate for the first time that sea turtles can detect DMS, an ability that might enable the identification of favorable foraging areas. PMID:23014568

  2. Achieving Mixtures of Ultra-High Performance Concrete

    Mircea POPA

    2013-07-01

    Full Text Available Ultra-High Performance Concrete (UHPC is a relatively new concrete. According to [11] UHPC is that concrete which features compressive strength over C100/115 class. Up to this point standards for this type of concrete were not adopted, although its characteristic strength exceeds those specified in [33]. Its main property is high compressive strength. This provides the possibility of reducing the section of elements (beams or columns made of this type of concrete, while the load capacity remains high. The study consists in blending mixtures of UHPC made of varying proportions of materials. The authors have obtained strengths of up to 160 MPa. The materials used are: Portland cement, silica fume, quartz powder, steel fibers, superplasticiser, sand and crushed aggregate for concrete - andesite.

  3. Environmental conditions and crop density as the limiting factors of forage maize production

    Dragičević Vesna D.

    2016-01-01

    Full Text Available In rain-fed cropping, defining the best combination of practices could achieve high forage yield and silage quality. The aim of this study was to compare energetic quality of produced silage with productive characteristics of forage maize cultivated on alluvium and hydromorphous black soil in rain-fed conditions at four plant densities (68-74,000 plants ha-1 during the period 2005- 2010. Yield and energy parameters were increased to some extent at higher crop densities indicating that higher densities (74,000 plants ha-1 were potentially better for high forage and DM yields, while lower densities (70,000 plants ha-1 were better for the increase of energy parameters of produced silage. [Projekat Ministarstva nauke Republike Srbije, br. TR-31037

  4. Computerised biofeedback achieving continence in high anal atresia.

    Owen-Smith, V H; Chesterfield, B W

    1986-01-01

    Computerised biofeedback has been used to attempt to improve continence in three boys with high anal atresia. The results obtained so far have been extremely encouraging. Over a period of six months progressive improvement has taken place and been maintained in each child.

  5. Organizational Citizenship of Faculty and Achievement of High School Students

    DiPaola, Michael F.; Hoy, Wayne K.

    2005-01-01

    All successful organizations, including successful high schools, have employees who go beyond their formal job responsibilities and freely give of their time and energy to succeed. Organ was the first to use the phrase "organizational citizenship behavior" (OCB) to denote organizationally beneficial behavior of workers that was not prescribed but…

  6. Scavenger: Transparent Development of Efficient Cyber Foraging Applications

    Kristensen, Mads Darø

    Cyber foraging is a pervasive computing technique where small mobile devices offload resource intensive tasks to stronger computing machinery in the vicinity. This paper presents Scavenger-a new cyber foraging system supporting easy development of mobile cyber foraging applications, while still...... delivering efficient, mobile use of remote computing resources through the use of a custom built mobile code execution environment and a new dual-profiling scheduler. One of the main difficulties within cyber foraging is that it is very challenging for application programmers to develop cyber foraging...... enabled applications. An application using cyber foraging is working with mobile, distributed and, possibly, parallel computing; fields within computer science known to be hard for programmers to grasp. In this paper it is shown by example, how a highly distributed, parallel, cyber foraging enabled...

  7. Achieving High Resolution Timer Events in Virtualized Environment

    Adamczyk, Blazej; Chydzinski, Andrzej

    2015-01-01

    Virtual Machine Monitors (VMM) have become popular in different application areas. Some applications may require to generate the timer events with high resolution and precision. This however may be challenging due to the complexity of VMMs. In this paper we focus on the timer functionality provided by five different VMMs—Xen, KVM, Qemu, VirtualBox and VMWare. Firstly, we evaluate resolutions and precisions of their timer events. Apparently, provided resolutions and precisions are far too low ...

  8. Achieving High Reliability Operations Through Multi-Program Integration

    Holly M. Ashley; Ronald K. Farris; Robert E. Richards

    2009-04-01

    Over the last 20 years the Idaho National Laboratory (INL) has adopted a number of operations and safety-related programs which has each periodically taken its turn in the limelight. As new programs have come along there has been natural competition for resources, focus and commitment. In the last few years, the INL has made real progress in integrating all these programs and are starting to realize important synergies. Contributing to this integration are both collaborative individuals and an emerging shared vision and goal of the INL fully maturing in its high reliability operations. This goal is so powerful because the concept of high reliability operations (and the resulting organizations) is a masterful amalgam and orchestrator of the best of all the participating programs (i.e. conduct of operations, behavior based safety, human performance, voluntary protection, quality assurance, and integrated safety management). This paper is a brief recounting of the lessons learned, thus far, at the INL in bringing previously competing programs into harmony under the goal (umbrella) of seeking to perform regularly as a high reliability organization. In addition to a brief diagram-illustrated historical review, the authors will share the INL’s primary successes (things already effectively stopped or started) and the gaps yet to be bridged.

  9. Telescoping Solar Array Concept for Achieving High Packaging Efficiency

    Mikulas, Martin; Pappa, Richard; Warren, Jay; Rose, Geoff

    2015-01-01

    Lightweight, high-efficiency solar arrays are required for future deep space missions using high-power Solar Electric Propulsion (SEP). Structural performance metrics for state-of-the art 30-50 kW flexible blanket arrays recently demonstrated in ground tests are approximately 40 kW/cu m packaging efficiency, 150 W/kg specific power, 0.1 Hz deployed stiffness, and 0.2 g deployed strength. Much larger arrays with up to a megawatt or more of power and improved packaging and specific power are of interest to mission planners for minimizing launch and life cycle costs of Mars exploration. A new concept referred to as the Compact Telescoping Array (CTA) with 60 kW/cu m packaging efficiency at 1 MW of power is described herein. Performance metrics as a function of array size and corresponding power level are derived analytically and validated by finite element analysis. Feasible CTA packaging and deployment approaches are also described. The CTA was developed, in part, to serve as a NASA reference solar array concept against which other proposed designs of 50-1000 kW arrays for future high-power SEP missions could be compared.

  10. Achieving High Burnup Targets With Mox Fuels: Techno Economic Implications

    For a typical MOX fuelled SFR of power reactor size, Implications due to higher burnup have been quantified. Advantages: – Improvement in the economy is seen upto 200 GWd/ t; Disadvantages: – Design changes > 150 GWd/ t bu; – Need for 8/ 16 more fuel SA at 150/ 200 GWd/ t bu; – Higher enrichment of B4C in CSR/ DSR at higher bu; – Reduction in LHR may be required at higher bu; – Structural material changes beyond 150 GWd/ t bu; – Reprocessing point of view-Sp Activity & Decay heat increase. Need for R & D is a must before increasing burnup. bu- refers burnup. Efforts to increase MOX fuel burnup beyond 200 GWd/ t may not be highly lucrative; • MOX fuelled FBR would be restricted to two or four further reactors; • Imported MOX fuelled FBRs may be considered; • India looks towards launching metal fuel FBRs in the future. – Due to high Breeding Ratio; – High burnup capability

  11. EFFECT OF EDUCATION ON ACHIEVEMENT MOTIVATION AMONG HIGH PROFILE AND LOW PROFILE COLLEGE STUDENTS

    DR. QUADRI SYED JAVEED

    2012-01-01

    The present study was undertaken to investigate the effect of education on achievement motivation among high profile and low profile college students. Sample of the study 200 college students. Hypothesis of the study 1. High educated college students have significantly high achievement motivation than the low educated college students. 2. High socio-economic status college students have significantly high achievement motivation than the low socio-economic status college students. Macre and Co...

  12. Self-learning Multiscale Simulation for Achieving High Accuracy and High Efficiency Simultaneously

    Li, Wenfei

    2009-01-01

    We propose a new multi-scale molecular dynamics simulation method which can achieve high accuracy and high sampling efficiency simultaneously without aforehand knowledge of the coarse grained (CG) potential and test it for a biomolecular system. Based on the resolution exchange simulations between atomistic and CG replicas, a self-learning strategy is introduced to progressively improve the CG potential by an iterative way. Two tests show that, the new method can rapidly improve the CG potential and achieve efficient sampling even starting from an unrealistic CG potential. The resulting free energy agreed well with exact result and the convergence by the method was much faster than that by the replica exchange method. The method is generic and can be applied to many biological as well as non-biological problems.

  13. Aggressive and foraging behavioral interactions among ruffe

    Savino, Jacqueline F.; Kostich, Melissa J.

    2000-01-01

    The ruffe, Gymnocephalus cernuus, is a nonindigenous percid in the Great Lakes. Ruffe are aggressive benthivores and forage over soft substrates. Laboratory studies in pools (100 cm in diameter, 15 cm water depth) were conducted to determine whether fish density (low = 2, medium = 4, high = 6 ruffe per pool) changed foraging and aggressive behaviors with a limited food supply of chironomid larvae. All fish densities demonstrated a hierarchy based on aggressive interactions, but ruffe were most aggressive at low and high fish densities. Time spent in foraging was lowest at the low fish density. The best forager at the low fish density was the most aggressive individual, but the second most aggressive fish at the medium and high fish density was the best forager and also the one chased most frequently. A medium fish density offered the best energetic benefits to ruffe by providing the lowest ratio of time spent in aggression to that spent foraging. Based on our results, ruffe should grow best at an intermediate density. With high ruffe densities, we would also expect disparity in size as the more aggressive fish are able to garner a disproportionate amount of the resources. Alternatively, as the Great Lakes are a fairly open system, ruffe could migrate out of one area to colonize another as populations exceed optimal densities.

  14. Forage polyphenol oxidase and ruminant livestock nutrition

    Lee, Michael R. F.

    2014-01-01

    Polyphenol oxidase (PPO) is predominately associated with the detrimental effect of browning fruit and vegetables, however, interest within PPO containing forage crops (crops to be fed to animals) has grown since the browning reaction was associated with reduced nitrogen (N) losses in silo and the rumen. The reduction in protein breakdown in silo of red clover (high PPO forage) increased the quality of protein, improving N-use efficiency [feed N into product N (e.g., Milk): NUE] when fed to r...

  15. Feeding of wheat bran and sugar beet pulp as sole supplements in high-forage diets emphasizes the potential of dairy cattle for human food supply.

    Ertl, P; Zebeli, Q; Zollitsch, W; Knaus, W

    2016-02-01

    Besides the widely discussed negative environmental effects of dairy production, such as greenhouse gas emissions, the feeding of large amounts of potentially human-edible feedstuffs to dairy cows is another important sustainability concern. The aim of this study was therefore to investigate the effects of a complete substitution of common cereal grains and pulses with a mixture of wheat bran and sugar beet pulp in a high-forage diet on cow performance, production efficiency, feed intake, and ruminating behavior, as well as on net food production potential. Thirteen multiparous and 7 primiparous mid-lactation Holstein dairy cows were randomly assigned to 1 of 2 treatments in a change-over design with 7-wk periods. Cows were fed a high-forage diet (grass silage and hay accounted for 75% of the dry matter intake), supplemented with either a cereal grain-based concentrate mixture (CON), or a mixture of wheat bran and dried sugar beet pulp (WBBP). Human-edible inputs were calculated for 2 different scenarios based on minimum and maximum potential recovery rates of human-edible energy and protein from the respective feedstuffs. Dietary starch and neutral detergent fiber contents were 3.0 and 44.1% for WBBP, compared with 10.8 and 38.2% in CON, respectively. Dietary treatment did not affect milk production, milk composition, feed intake, or total chewing activity. However, chewing index expressed in minutes per kilogram of neutral detergent fiber ingested was 12% lower in WBBP compared with CON. In comparison to CON, the human-edible feed conversion efficiencies for energy and protein, defined as human-edible output per human-edible input, were 6.8 and 5.3 times higher, respectively, in WBBP under the maximum scenario. For the maximum scenario, the daily net food production (human-edible output minus human-edible input) increased from 5.4 MJ and 250 g of crude protein per cow in CON to 61.5 MJ and 630 g of crude protein in the WBBP diet. In conclusion, our data suggest

  16. COMPARATIVE PERSPECTIVES OF STUDY STRATEGIES AMONG HIGH AND LOW ACHIEVERS DISTANCE LEARNING STUDENTS

    Muhammad Imran YOUSUF

    2009-07-01

    Full Text Available The main aim of this research is to better understand and draw perceptions of low and high achiever distance learners about their study patterns. The study indicates the areas where significant difference is found among low and high achievers of Allama Iqbal Open University, Pakistan through a self developed questionnaire covering their preferred study location, study times, number of hours spent on study, the difficulties affecting their study patterns and the organization of study strategies in comparative perspective. Greater difficulties were being faced by low achievers in their study. Increased difficulties were encountered by low achievers with study material, volume of study, self-motivation and other factors. There was no significant difference between low and high achievers for their study strategies of studying materials without taking notes and reading aloud. Greater low achievers attempted easy portions of their study material first and took notes simultaneously as compared to high achievers.

  17. Neural Mechanisms of Foraging

    Kolling, Nils; Behrens, Timothy EJ; Mars, Rogier B.; Rushworth, Matthew FS

    2012-01-01

    Behavioural economic studies, involving limited numbers of choices, have provided key insights into neural decision-making mechanisms. By contrast, animals’ foraging choices arise in the context of sequences of encounters with prey/food. On each encounter the animal chooses to engage or whether the environment is sufficiently rich that searching elsewhere is merited. The cost of foraging is also critical. We demonstrate humans can alternate between two modes of choice, comparative decision-ma...

  18. The Chinese High School Student's Stress in the School and Academic Achievement

    Liu, Yangyang; Lu, Zuhong

    2011-01-01

    In a sample of 466 Chinese high school students, we examined the relationships between Chinese high school students' stress in the school and their academic achievements. Regression mixture modelling identified two different classes of the effects of Chinese high school students' stress on their academic achievements. One class contained 87% of…

  19. English and Mathematics: Determinants of Physics Achievement among Public High School Seniors in Naga City

    DR. EDGAR M. BAYLON, JR.

    2014-01-01

    This evaluative and relational study determined the influence of English and Mathematics on the Physics achievement of public high school senior students in Naga City, Philippines. Results showed that the students had an average achievement level in Speaking, Reading, Literature and Grammar. The overall achievement level in Advanced Algebra, Trigonometry and Statistics was average. The overall achievement level in Optics and Waves, Nuclear Physics and Mechanics was average. There was a signif...

  20. Fishing amplifies forage fish population collapses

    Essington, Timothy E.; Moriarty, Pamela E.; Froehlich, Halley E.; Hodgson, Emma E.; Koehn, Laura E.; Oken, Kiva L.; Siple, Margaret C.; Stawitz, Christine C.

    2015-01-01

    Forage fish support the largest fisheries in the world but also play key roles in marine food webs by transferring energy from plankton to upper trophic-level predators, such as large fish, seabirds, and marine mammals. Fishing can, thereby, have far reaching consequences on marine food webs unless safeguards are in place to avoid depleting forage fish to dangerously low levels, where dependent predators are most vulnerable. However, disentangling the contributions of fishing vs. natural processes on population dynamics has been difficult because of the sensitivity of these stocks to environmental conditions. Here, we overcome this difficulty by collating population time series for forage fish populations that account for nearly two-thirds of global catch of forage fish to identify the fingerprint of fisheries on their population dynamics. Forage fish population collapses shared a set of common and unique characteristics: high fishing pressure for several years before collapse, a sharp drop in natural population productivity, and a lagged response to reduce fishing pressure. Lagged response to natural productivity declines can sharply amplify the magnitude of naturally occurring population fluctuations. Finally, we show that the magnitude and frequency of collapses are greater than expected from natural productivity characteristics and therefore, likely attributed to fishing. The durations of collapses, however, were not different from those expected based on natural productivity shifts. A risk-based management scheme that reduces fishing when populations become scarce would protect forage fish and their predators from collapse with little effect on long-term average catches. PMID:25848018

  1. An Analysis of Java Programming Behaviors, Affect, Perceptions, and Syntax Errors among Low-Achieving, Average, and High-Achieving Novice Programmers

    Rodrigo, Ma. Mercedes T.; Andallaza, Thor Collin S.; Castro, Francisco Enrique Vicente G.; Armenta, Marc Lester V.; Dy, Thomas T.; Jadud, Matthew C.

    2013-01-01

    In this article we quantitatively and qualitatively analyze a sample of novice programmer compilation log data, exploring whether (or how) low-achieving, average, and high-achieving students vary in their grasp of these introductory concepts. High-achieving students self-reported having the easiest time learning the introductory programming…

  2. Energetic Optimisation of Foraging Honeybees: Flexible Change of Strategies in Response to Environmental Challenges

    Anton Stabentheiner; Helmut Kovac

    2014-01-01

    Heterothermic insects like honeybees, foraging in a variable environment, face the challenge of keeping their body temperature high to enable immediate flight and to promote fast exploitation of resources. Because of their small size they have to cope with an enormous heat loss and, therefore, high costs of thermoregulation. This calls for energetic optimisation which may be achieved by different strategies. An 'economizing' strategy would be to reduce energetic investment whenever possible, ...

  3. The Effect of the Time Management Art on Academic Achievement among High School Students in Jordan

    Al-Zoubi, Maysoon

    2016-01-01

    This study aimed at recognizing the effect of the Time Management Art on academic achievement among high school students in the Hashemite Kingdom of Jordan. The researcher employed the descriptive-analytic research to achieve the purpose of the study where he chose a sample of (2000) high school female and male students as respondents to the…

  4. Adaptive collective foraging in groups with conflicting nutritional needs.

    Senior, Alistair M; Lihoreau, Mathieu; Charleston, Michael A; Buhl, Jerome; Raubenheimer, David; Simpson, Stephen J

    2016-04-01

    Collective foraging, based on positive feedback and quorum responses, is believed to improve the foraging efficiency of animals. Nutritional models suggest that social information transfer increases the ability of foragers with closely aligned nutritional needs to find nutrients and maintain a balanced diet. However, whether or not collective foraging is adaptive in a heterogeneous group composed of individuals with differing nutritional needs is virtually unexplored. Here we develop an evolutionary agent-based model using concepts of nutritional ecology to address this knowledge gap. Our aim was to evaluate how collective foraging, mediated by social retention on foods, can improve nutrient balancing in individuals with different requirements. The model suggests that in groups where inter-individual nutritional needs are unimodally distributed, high levels of collective foraging yield optimal individual fitness by reducing search times that result from moving between nutritionally imbalanced foods. However, where nutritional needs are highly bimodal (e.g. where the requirements of males and females differ) collective foraging is selected against, leading to group fission. In this case, additional mechanisms such as assortative interactions can coevolve to allow collective foraging by subgroups of individuals with aligned requirements. Our findings indicate that collective foraging is an efficient strategy for nutrient regulation in animals inhabiting complex nutritional environments and exhibiting a range of social forms. PMID:27152206

  5. Achieving combined high strength and high conductivity in re-processed Cu-Cr alloy

    A.O. Olofinjanaa

    2009-07-01

    Full Text Available Purpose: Precipitation hardening by nano-sized precipitates had proven to be the most adequate way to achieve the optimum combination for strength and conductivity in copper based alloys. However, precipitation strengthened Cu- alloys are limited to very dilute concentration thereby limiting the volume proportion hardening precipitates. In this work, we report the investigation of the reprocessing of higher Cr concentration Cu- based alloys via rapid solidification.Design/methodology/approach: The ingot alloys with Cr content up to 10 wt.% were prepared via semi-chilling of small rods before been cast into ribbon using chill block melt spinner. Thermal aging studies followed by conductivity and microhardness tests were performed to follow the HSHC properties.Findings: It is found that the rapid solidification in the as-cast ribbon imposed combined solution extension and ultra-refinement of Cr rich phases. X-ray diffraction evidences suggest that the solid solution extension was up to 6wt%Cr. Lattice parameters determined confirmed the many folds extension of solid solution of Cr in Cu. Thermal aging studies of the cast ribbons indicated that peak aging treatments occurred in about twenty minutes. Peak aged hardness ranged from about 200 to well over 300Hv. The maximum peak aged hardness of 380Hv was obtained for alloy containing 6wt.%Cr but with conductivity of about 50%IACS. The best combined strength/conductivity was obtained for 4wt.%Cr alloy with hardness of 350HV and conductivity of 80% IACS. The high strengths observed are attributed to the increased volume proportion of semi-coherent Cr rich nano-sized precipitates that evolved from the supersaturated solid solution of Cu-Cr that was achieved from the high cooling rates imposed by the ribbon casting processResearch limitations/implications: The rapid overaging of the high Cr concentration Cu-Cr alloy is still a cause for concern in optimising the process for reaching peak HSHC properties

  6. Redesigning forages with condensed tannins

    Maximizing protein content in forages and minimizing protein loss during silage fermentation and rumen digestion are concerns for livestock and dairy producers. Substantial amounts of forage protein undergo proteolysis (breakdown) during the ensiling process and during rumen fermentation, transforme...

  7. Postweaning substitution of grazed forage with a high-energy concentrate has variable long-term effects on subcutaneous fat and marbling in Bos taurus genotypes.

    Greenwood, P L; Siddell, J P; Walmsley, B J; Geesink, G H; Pethick, D W; McPhee, M J

    2015-08-01

    The objective of this study was to quantify the effects and interactions of stage of growth and genotype on commercial carcass traits and intramuscular fat (IMF) content in 5 muscles of steers ( = 165) and to test the hypothesis that substituting pasture with a high-energy concentrate during the immediate postweaning period increases IMF. Cattle of 3 genotypes (Angus, Hereford, and Wagyu × Angus; = 55/genotype) were selected at weaning from commercial herds, targeting genotypic differences in marbling and subcutaneous fatness. Following weaning, steers were fed for 168 d within 2 different improved, temperate pasture-based nutritional systems: a forage-only system (FS) and forage with high-energy supplemented system (SS), with 2 replicates per system. The supplement was fed at a level of 1% of average BW adjusted every 2 wk to provide an estimated 50% of energy requirements for 168 d from weaning. Pasture on offer in both systems was managed to match the BW of the FS and SS steers during the postweaning treatment period to avoid confounding due to differences in growth rate during this period. Steers were then regrouped into 2 replicates and backgrounded on improved, temperate pasture for 158 d and then grain fed within 1 group for 105 d (short fed) or 259 d (long fed). Groups were slaughtered at commencement (d 0) and end of postweaning nutritional treatments (d 168), end of backgrounding (d 326), and after short (d 431) or long feedlotting (d 585). Serial slaughter stage had an effect on all traits assessed ( < 0.01). The FS steers had more rib fat ( < 0.01) and higher Meat Standards Australia marbling score ( < 0.05) and a tendency ( < 0.10) to have greater eye muscle area than the SS steers throughout the study. Genotypic differences were evident ( < 0.05) for all traits assessed except HCW, dressing percentage, rib fat depth, ossification score, ultimate pH, and IMF in the semitendinosus muscle. The results for marbling and IMF do not support the use of a

  8. Little auks ( Alle alle ) breeding in a High Arctic fjord system: bimodal foraging strategies as a response to poor food quality?

    Steen, Harald; Vogedes, Daniel; Broms, Fredrik; Falk-Petersen, Stig; Berge, Jørgen

    2007-01-01

    The foraging behaviour of little auks ( Alle alle ) in the Bjørndalen colony on the western coast of Spitsbergen was studied during the breeding season 2005. The duration of foraging trips and contents of gular pouches were analysed. Quantitative zooplankton samples procured in the vicinity of the colony facilitated a comparison between gular pouch contents and the availability of prey species. Zooplankton and gular pouch samples were all sampled within a time window of approximately one week...

  9. Achieving high strength and high ductility in magnesium alloy using hard-plate rolling (HPR) process

    Wang, Hui–Yuan; Yu, Zhao–Peng; Zhang, Lei; Liu, Chun–Guo; Zha, Min; Wang, Cheng; Jiang, Qi–Chuan

    2015-11-01

    Magnesium alloys are highly desirable for a wide range of lightweight structural components. However, rolling Mg alloys can be difficult due to their poor plasticity, and the strong texture yielded from rolling often results in poor plate forming ability, which limits their further engineering applications. Here we report a new hard-plate rolling (HPR) route which achieves a large reduction during a single rolling pass. The Mg-9Al-1Zn (AZ91) plates processed by HPR consist of coarse grains of 30-60 μm, exhibiting a typical basal texture, fine grains of 1-5 μm and ultrafine (sub) grains of 200-500 nm, both of the latter two having a weakened texture. More importantly, the HPR was efficient in gaining a simultaneous high strength and uniform ductility, i.e., ~371 MPa and ~23%, respectively. The superior properties should be mainly attributed to the cooperation effect of the multimodal grain structure and weakened texture, where the former facilitates a strong work hardening while the latter promotes the basal slip. The HPR methodology is facile and effective, and can avoid plate cracking that is prone to occur during conventional rolling processes. This strategy is applicable to hard-to-deform materials like Mg alloys, and thus has a promising prospect for industrial application.

  10. Collective foraging in heterogeneous landscapes

    Bhattacharya, Kunal; Vicsek, Tamás

    2013-01-01

    Animals foraging alone are hypothesized to optimize the encounter rates with resources through Lévy walks. However, the issue of how the interactions between multiple foragers influence their search efficiency is still not completely understood. To address this, we consider a model to study the optimal strategy for a group of foragers searching for targets distributed heterogeneously. In our model, foragers move on a square lattice containing immobile but regenerative targets. At any instant,...

  11. English and Mathematics: Determinants of Physics Achievement among Public High School Seniors in Naga City

    DR. EDGAR M. BAYLON, JR.

    2014-02-01

    Full Text Available This evaluative and relational study determined the influence of English and Mathematics on the Physics achievement of public high school senior students in Naga City, Philippines. Results showed that the students had an average achievement level in Speaking, Reading, Literature and Grammar. The overall achievement level in Advanced Algebra, Trigonometry and Statistics was average. The overall achievement level in Optics and Waves, Nuclear Physics and Mechanics was average. There was a significant positive relationship between English and Physics achievement, and between Mathematics and Physics Achievement. Reading, Literature and Grammar were the areas in English that significantly influenced Physics achievement. In Mathematics, Advanced Algebra and Trigonometry significantly influenced Physics achievement. The students’ achievement between English and Physics had no significant difference at 1% level but significantly different at 5% level. Mathematics and Physics achievement had no significant difference at 1% and 5% levels. There was no significant difference between schools C and D; A and C; and schools B and C at 5% and 1% levels. However, the achievement level between schools A and B, B and D, and schools A and D were significantly different at 1% level.

  12. Unforgiving Confucian Culture: A Breeding Ground for High Academic Achievement, Test Anxiety and Self-Doubt?

    Stankov, Lazar

    2010-01-01

    This paper reviews findings from several studies that contribute to our understanding of cross-cultural differences in academic achievement, anxiety and self-doubt. The focus is on comparisons between Confucian Asian and European regions. Recent studies indicate that high academic achievement of students from Confucian Asian countries is…

  13. Instructional, Transformational, and Managerial Leadership and Student Achievement: High School Principals Make a Difference

    Valentine, Jerry W.; Prater, Mike

    2011-01-01

    This statewide study examined the relationships between principal managerial, instructional, and transformational leadership and student achievement in public high schools. Differences in student achievement were found when schools were grouped according to principal leadership factors. Principal leadership behaviors promoting instructional and…

  14. Parental Involvement, Homework, and TV Time: Direct and Indirect Effects on High School Achievement.

    Keith, Timothy Z.; And Others

    1986-01-01

    A set of High School and Beyond data was used to study the effect of three variables on academic achievement. Homework had a positive effect, TV a negative, and parental involvement no direct effect on seniors' achievement scores, but influenced the amount of time students spent on homework. (Author/JAZ)

  15. Gender and High School Chemistry: Student Perceptions on Achievement in a Selective Setting

    Cousins, Andrew; Mills, Martin

    2015-01-01

    This paper reports on research undertaken in a middle-class Australian school. The focus of the research was on the relationship between gender and students' engagement with high school chemistry. Achievement data from many OECD [Organisation for Economic Co-operation and Development] countries suggest that middle-class girls are achieving equally…

  16. Cohort versus Non-Cohort High School Students' Math Performance: Achievement Test Scores and Coursework

    Parke, Carol S.; Keener, Dana

    2011-01-01

    The purpose of this study is to compare multiple measures of mathematics achievement for 1,378 cohort students who attended the same high school in a district from 9th to 12th grade with non-cohort students in each grade level. Results show that mobility had an impact on math achievement. After accounting for gender, ethnicity, and SES, adjusted…

  17. Optimal Foraging in Semantic Memory

    Hills, Thomas T.; Jones, Michael N.; Todd, Peter M.

    2012-01-01

    Do humans search in memory using dynamic local-to-global search strategies similar to those that animals use to forage between patches in space? If so, do their dynamic memory search policies correspond to optimal foraging strategies seen for spatial foraging? Results from a number of fields suggest these possibilities, including the shared…

  18. Habitat-specific foraging strategies in Australasian gannets

    Melanie R. Wells

    2016-07-01

    Full Text Available Knowledge of top predator foraging adaptability is imperative for predicting their biological response to environmental variability. While seabirds have developed highly specialised techniques to locate prey, little is known about intraspecific variation in foraging strategies with many studies deriving information from uniform oceanic environments. Australasian gannets (Morus serrator typically forage in continental shelf regions on small schooling prey. The present study used GPS and video data loggers to compare habitat-specific foraging strategies at two sites of contrasting oceanographic regimes (deep water near the continental shelf edge, n=23; shallow inshore embayment, n=26, in south-eastern Australia. Individuals from the continental shelf site exhibited pelagic foraging behaviours typical of gannet species, using local enhancement to locate and feed on small schooling fish; in contrast only 50% of the individuals from the inshore site foraged offshore, displaying the typical pelagic foraging strategy. The remainder adopted a strategy of searching sand banks in shallow inshore waters in the absence of conspecifics and other predators for large, single prey items. Furthermore, of the individuals foraging inshore, 93% were male, indicating that the inshore strategy may be sex-specific. Large inter-colony differences in Australasian gannets suggest strong plasticity in foraging behaviours, essential for adapting to environmental change.

  19. Habitat-specific foraging strategies in Australasian gannets

    Wells, Melanie R.; Arnould, John P. Y.

    2016-01-01

    ABSTRACT Knowledge of top predator foraging adaptability is imperative for predicting their biological response to environmental variability. While seabirds have developed highly specialised techniques to locate prey, little is known about intraspecific variation in foraging strategies with many studies deriving information from uniform oceanic environments. Australasian gannets (Morus serrator) typically forage in continental shelf regions on small schooling prey. The present study used GPS and video data loggers to compare habitat-specific foraging strategies at two sites of contrasting oceanographic regimes (deep water near the continental shelf edge, n=23; shallow inshore embayment, n=26), in south-eastern Australia. Individuals from the continental shelf site exhibited pelagic foraging behaviours typical of gannet species, using local enhancement to locate and feed on small schooling fish; in contrast only 50% of the individuals from the inshore site foraged offshore, displaying the typical pelagic foraging strategy. The remainder adopted a strategy of searching sand banks in shallow inshore waters in the absence of conspecifics and other predators for large, single prey items. Furthermore, of the individuals foraging inshore, 93% were male, indicating that the inshore strategy may be sex-specific. Large inter-colony differences in Australasian gannets suggest strong plasticity in foraging behaviours, essential for adapting to environmental change. PMID:27305927

  20. Incremental amounts of Ascophyllum nodosum meal do not improve animal performance but do increase milk iodine output in early lactation dairy cows fed high-forage diets.

    Antaya, N T; Soder, K J; Kraft, J; Whitehouse, N L; Guindon, N E; Erickson, P S; Conroy, A B; Brito, A F

    2015-03-01

    The objective of this study was to investigate the effects of incremental amounts of Ascophyllum nodosum meal (ANOD) on milk production, milk composition including fatty acids and I, blood metabolites, and nutrient intake and digestibility in early lactation dairy cows fed high-forage diets. Twelve multiparous Jersey cows averaging (mean±standard deviation) 40±21 d in milk and 464±35 kg of body weight and 4 primiparous Jersey cows averaging 75±37 d in milk and 384±17kg of body weight were randomly assigned to treatment sequences in a replicated 4×4 Latin square design. Each period lasted 21 d with 14 d for diet adaptation and 7 d for data and sample collection. Cows were fed a total mixed ration (64:36 forage-to-concentrate ratio) supplemented (as fed) with 0, 57, 113, or 170 g/d of ANOD. Milk yield as well as concentrations and yields of milk components (fat, protein, lactose, milk urea N) were not affected by increasing dietary amounts of ANOD. Concentration (from 178 to 1,370 µg/L) and yield (from 2.8 to 20.6 mg/d) of milk I increased linearly in cows fed incremental amounts of ANOD as a result of the high concentration of I (820 mg/kg of dry matter) in ANOD. Overall, only minor changes were observed in the proportion of milk fatty acids with ANOD supplementation. Quadratic trends were observed for dry matter intake and total-tract digestibilities of organic matter and neutral detergent fiber, whereas negative linear trends were observed for serum concentration of cortisol and crude protein digestibility with ANOD supplementation. Serum concentrations of triiodothyronine and thyroxine were not affected by ANOD supplementation and averaged 1.1 and 48.4 ng/mL, respectively. However, feeding increasing amounts of ANOD linearly reduced the plasma concentration of nonesterified fatty acids (from 164 to 132 mEq/L). Quadratic effects were found for the total-tract digestibility of ADF and urinary output of purine derivatives, suggesting that ANOD supplementation

  1. Effect of Propionibacterium spp. on ruminal fermentation, nutrient digestibility, and methane emissions in beef heifers fed a high-forage diet.

    Vyas, D; McGeough, E J; McGinn, S M; McAllister, T A; Beauchemin, K A

    2014-05-01

    The objective of this study was to test the efficacy of different Propionibacterium strains in mitigating methane (CH4) emissions in beef heifers fed a high-forage diet. Twenty ruminally cannulated beef heifers were used in a randomized block design with 28-d periods. Treatments included 1) Control, 2) Propionibacterium acidipropionici strain P169, 3) Propionibacterium acidipropionici strain P5, and 4) Propionibacterium jensenii strain P54. Strains (5 × 10(9) CFU) were administered daily directly into the rumen in 10 g of a maltodextrin carrier in a gel capsule. Control heifers received the carrier only. All heifers were fed a basal diet (70:30 forage to concentrate, DM basis) based on barley silage and corn grain. No treatment effects were observed for overall DMI (P = 0.78) or DMI in chambers (P = 0.29). Dry matter intake was 12 to 29% less in the chambers, with intake depression numerically lower in heifers receiving Propionibacterium than Control. Mean ruminal pH averaged 6.47 and was not affected by treatments (P = 0.34). Likewise, no treatment differences were observed for ruminal concentrations of total VFA (P = 0.24) and ammonia-N (P = 0.49) or for molar proportion of individual VFA. Total daily enteric CH4 production was not affected by Propionibacterium strains as compared to Control and averaged 178 g/d (P = 0.69). However, enteric CH4 emission intensity (g CH4/kg of DMI) was reduced by 12, 8, and 13% with P169, P5, and P54 as compared to Control, respectively (P = 0.03). No treatment effects were observed for total tract digestibility of nutrients. Likewise, total universal bacterial (P = 0.22) and methanogen (P = 0.64) counts were similar among treatments. However, the relative abundance of total Propionibacteria tended to increase with inoculation as compared to Control (P = 0.06). The relative abundance of Propionibacterium P169 tended to be greater at 3 h postdosing, but returned to pretreatment (0 h) levels within 9 h, suggesting it failed to

  2. Arboreal forage lichen response to partial cutting of high elevation mountain caribou range in the Quesnel Higland of east-central British Columbia

    Michaela J. Waterhouse

    2007-04-01

    Full Text Available Group selection silvicultural systems have been recommended for managing mountain caribou (Rangifer tarandus caribou habitat in high elevation Engelmann spruce – subalpine fir forests in east-central British Columbia. We measured the response of arboreal lichen (a key winter forage to harvesting of 30% of the forested area using three partial cutting treatments, which created small (0.03 ha, medium (0.13 ha, and large (1.0 ha openings, and a no-harvest treatment. Treatments were replicated on four sites, and monitored over a ten year post-harvest period. The short-term loss of lichen associated with removal of approximately one third of the trees was partially offset by a significant (P=0.01 increase in lichen abundance on trees in the caribou feeding zone (up to 4.5 m in the three partial cutting treatments relative to trees in the uncut forest. Differences among treatments in the change in lichen composition, as measured by the percentage of Alectoria sarmentosa and Bryoria spp., were marginally significant (P=0.10. The partial cutting treatments showing a greater likelihood of shifting towards more Bryoria spp. than no-harvest treatment (P=0.04. In the year of harvest (1993, larger trees were found to hold more lichen than smaller trees (P=0.04, and live trees supported more lichen than dead trees (P=0.01, but lichen loading was similar among tree species (P=0.51. Tree fall rates were similar among treatments, based on the ten year average (0.6–0.8% of sample trees per year. The results indicate that caribou foraging habitat is maintained in the residual forest when group selection systems that remove only 30% of the trees are applied. Information on the distribution of lichen is useful for developing stand level prescriptions. Providing lichen bearing habitat meets just one of the needs of caribou. A comprehensive approach that considers all factors and their interactions is essential to maintain and recover the threatened mountain

  3. [Optimized Spectral Indices Based Estimation of Forage Grass Biomass].

    An, Hai-bo; Li, Fei; Zhao, Meng-li; Liu, Ya-jun

    2015-11-01

    As an important indicator of forage production, aboveground biomass will directly illustrate the growth of forage grass. Therefore, Real-time monitoring biomass of forage grass play a crucial role in performing suitable grazing and management in artificial and natural grassland. However, traditional sampling and measuring are time-consuming and labor-intensive. Recently, development of hyperspectral remote sensing provides the feasibility in timely and nondestructive deriving biomass of forage grass. In the present study, the main objectives were to explore the robustness of published and optimized spectral indices in estimating biomass of forage grass in natural and artificial pasture. The natural pasture with four grazing density (control, light grazing, moderate grazing and high grazing) was designed in desert steppe, and different forage cultivars with different N rate were conducted in artificial forage fields in Inner Mongolia. The canopy reflectance and biomass in each plot were measured during critical stages. The result showed that, due to the influence in canopy structure and biomass, the canopy reflectance have a great difference in different type of forage grass. The best performing spectral index varied in different species of forage grass with different treatments (R² = 0.00-0.69). The predictive ability of spectral indices decreased under low biomass of desert steppe, while red band based spectral indices lost sensitivity under moderate-high biomass of forage maize. When band combinations of simple ratio and normalized difference spectral indices were optimized in combined datasets of natural and artificial grassland, optimized spectral indices significant increased predictive ability and the model between biomass and optimized spectral indices had the highest R² (R² = 0.72) compared to published spectral indices. Sensitive analysis further confirmed that the optimized index had the lowest noise equivalent and were the best performing index in

  4. EFFECTS OF FORAGE SPECIES ON FATTY ACID COMPOSITION OF BEEF LONGISSIMUS MUSCLE FROM FORAGE-FINISHED BEEF

    Forty-seven Angus-crossbred steers were used to evaluate the effects of forage species grazed in the last 41 d of the finishing period on rib composition, color, and palatability in forage-finished beef and compared to traditional high concentrate finished. Steers grazed naturalized pastures (bluegr...

  5. Field application of mycorrhizal bio-inoculants affects the mineral uptake of a forage legume (Hedysarum coronarium L.) on a highly calcareous soil.

    Labidi, S; Jeddi, F Ben; Tisserant, B; Yousfi, M; Sanaa, M; Dalpé, Y; Sahraoui, A Lounès-Hadj

    2015-05-01

    The efficiency of two mycorrhizal bio-inoculants on the mineral uptake during the growth stages of a Mediterranean forage legume sulla (Hedysarum coronarium L.) was studied in the field on a highly calcareous soil. The first inoculum (Mm) was made up of a mixture of native arbuscular mycorrhizal fungi (AMF) isolated from calcareous soils: Septoglomus constrictum, Funneliformis geosporum, Glomus fuegianum, Rhizophagus irregularis and Glomus sp. The second was a commercial inoculum (Mi) containing one AMF species: R. irregularis. Both mycorrhizal inoculants increased total and arbuscular colonization of sulla roots. Inoculation with Mm showed a positive effect on sulla shoot dry weight (SDW) when compared to Mi and non-inoculated plants (control). Mineral contents (P, Mg, Mn, Fe) were higher in the shoots of sulla plants cultivated on mycorrhiza-inoculated plots compared to non-inoculated ones. This enhancement was observed during the flowering stage for P, Mg and Mn and during the rosette stage for Fe. An increase in P content of 50 % in plants inoculated with Mm compared to non-inoculated ones may be explained by the induction of root alkaline and acid phosphatase activities. Higher efficiency of native AMF species adapted to calcareous soils opens the way towards the development of mycorrhiza bio-fertilizers targeted to improve sustainable fertilization management in such soils. PMID:25323044

  6. Fatty acid profile, meat quality, and carcass traits of Nellore young bulls fed different sources of forage in high-concentrate diets with crude glycerin

    Andressa Ferreira Ribeiro

    2016-04-01

    Full Text Available ABSTRACT The objectives of this study were to evaluate the effect of forages with different nutritional values - specifically, corn silage (CS, sugar cane (SC, and sugar cane bagasse (SB - in diets with crude glycerin, on carcass traits, meat quality, and fatty acid profile, using young Nellore bulls finished in the feedlot. Thirty young Nellore bulls with an initial average body weight of 416.70±24.74 kg were randomly assigned to three treatments containing different sources of forage. The carcass traits and variables related to meat quality of the Nellore young bulls were not significantly influenced by different sources of forage in diets with crude glycerin. The yellow color index was significantly greater in the fat of animals fed corn silage. Heptadecenoic fatty acid was significantly lower in the meat of animals fed sugar cane bagasse. The sources of forage in diets with crude glycerin did not influence the profile of saturated, monounsaturated, or polyunsaturated fatty acids in the longissimus muscle. Overall, our results indicate that none of the treatments changed the carcass and meat quality traits of Nellore young bulls finished in the feedlot. Thus, sugar cane and sugar cane bagasse could be used in feedlot as a viable forage alternative to corn silage.

  7. Factors affecting forage stand establishment Fatores que afetam o estabelecimento do estande em plantas forrageiras

    Sulc, R.M.

    1998-01-01

    Significant advances have been made in our knowledge of forage seed physiology, technology, and stand establishment practices; however, stand establishment continues to be one of the most common production problems affecting forage crops in the USA. There is a need for research on stand establishment of forage crops under abiotic and biotic stress. Although the forage seed industry produces and markets seed of high quality, new methods of assessing seed vigor are needed and their use should b...

  8. Breeding Better Forages to Help Feed Man and Preserve and Enhance the Environment

    Burton, Glenn W.

    1973-01-01

    Discusses the importance of forages in agriculture, and expresses the need for the same high level of technology that is used in the production of corn, wheat, and rice to be applied to forage production. Describes promising forage species, breeding objectives, and breeding procedures used in research. (JR)

  9. Honeybee foraging in differentially structured landscapes.

    Steffan-Dewenter, Ingolf; Kuhn, Arno

    2003-03-22

    Honeybees communicate the distance and location of resource patches by bee dances, but this spatial information has rarely been used to study their foraging ecology. We analysed, for the first time to the best of the authors' knowledge, foraging distances and dance activities of honeybees in relation to landscape structure, season and colony using a replicated experimental approach on a landscape scale. We compared three structurally simple landscapes characterized by a high proportion of arable land and large patches, with three complex landscapes with a high proportion of semi-natural perennial habitats and low mean patch size. Four observation hives were placed in the centre of the landscapes and switched at regular intervals between the six landscapes from the beginning of May to the end of July. A total of 1137 bee dances were observed and decoded. Overall mean foraging distance was 1526.1 +/- 37.2 m, the median 1181.5 m and range 62.1-10037.1 m. Mean foraging distances of all bees and foraging distances of nectar-collecting bees did not significantly differ between simple and complex landscapes, but varied between month and colonies. Foraging distances of pollen-collecting bees were significantly larger in simple (1743 +/- 95.6 m) than in complex landscapes (1543.4 +/- 71 m) and highest in June when resources were scarce. Dancing activity, i.e. the number of observed bee dances per unit time, was significantly higher in complex than in simple landscapes, presumably because of larger spatial and temporal variability of resource patches in complex landscapes. The results facilitate an understanding of how human landscape modification may change the evolutionary significance of bee dances and ecological interactions, such as pollination and competition between honeybees and other bee species. PMID:12769455

  10. Evaluation of English Achievement Test: A Comparison between High and Low Achievers amongst Selected Elementary School Students of Pakistan

    Haider, Zubair; Latif, Farah; Akhtar, Samina; Mushtaq, Maria

    2012-01-01

    Validity, reliability and item analysis are critical to the process of evaluating the quality of an educational measurement. The present study evaluates the quality of an assessment constructed to measure elementary school student's achievement in English. In this study, the survey model of descriptive research was used as a research method.…

  11. The Relationship between Cognitive and Emotional Intelligence and High School Academic Achievement.

    Matešić, Krunoslav

    2015-06-01

    The study investigated the relationship between intelligence, emotional intelligence and academic achievement in high school. The study was conducted within the standardization of two instruments for Croatian samples. A total of 369 high school students from the Republic of Croatia participated in the study. They completed the Naglieri Nonverbal Ability Test (NNAT)--a test of cognitive intelligence and the BarOn Emotional Quotient Inventory: Youth Version (EQ-i:YV). Academic achievement criteria were general school achievement, Croatian language and mathematics. Several regression analyses were conducted on the results. The results show that cognitive intelligence and the adaptability scale to be consistent predictors of academic achievement. Emotional intelligence was not shown to be a significant predictor of school success. PMID:26753453

  12. Resilience influence, goals and social context in the academic achievement of high school students

    José Concepción Gaxiola Romero

    2012-05-01

    Full Text Available The academic achievement in high school students of Mexico, according to national and international evaluations has been insufficient. In spite of this situation, is possible to find excellent students, even in the context of sharing negative contextual and physical conditions. There are few investigations that describe the variables associated to resilient students. The alumni that are beyond the risks are called resilient (Rutter, 2007. The aim of this research was to explore and identify the internal variables: goals and resilience, and the external variables: risky neighborhood and risky friends that predicted the scholar achievement of high school students. To measure those variables, was used a compilation of scales validated in the region. The data were analyzed using structural equation modeling, and show that resilience predicted indirectly the scholar achievement trough the academic goals. The results could be used in programs to improve the academic achievement of this group of students.

  13. A Study On Scientific Aptitude Of High School Students In Relation To Their Achievement In Science

    P.N. Nataraj; Manjula, G

    2012-01-01

    In the present study the researcher has attempted to study the Scientific Aptitude of high school students in relation to their achievement in science. The investigation was carried out on 650, 9th standard students using the Scientific Aptitude Battery by Dr. K.K. Agarwal, and achievement test in science constructed and standardized by investigator. Descriptive Statistics Differential Analysis and Correlation were used to analyses the data. The findings of the study on Scientific...

  14. Impact of Principal Leadership on Catholic High School Students' Academic Achievement in Edo State, Nigeria

    Imhangbe, Osayamen Samson

    2012-01-01

    Over the years, students of Catholic High/Senior secondary schools in Edo state, Nigeria have maintained a significantly higher level of academic achievement than their counterparts in public schools in the state. This development has not only been a cause of serious concern for parents of students who attend public High/Senior secondary schools…

  15. School Context, Precollege Educational Opportunities, and College Degree Attainment among High-Achieving Black Males

    Rose, Valija C.

    2013-01-01

    Access to high-quality educational opportunities is central to growing postsecondary degree attainment. This study employs secondary data analysis of the public-use National Education Longitudinal Study (NELS:88/00) to examine how school context and precollege educational opportunities influence college degree attainment among high-achieving Black…

  16. Emotional Intelligence as a Predictor of Leadership of Kuwaiti High and Low Achieving 11th Graders

    Alnabhan, Mousa

    2010-01-01

    The current study examined the association between emotional intelligence (EI) and the Leadership components (L) of high school students in the state of Kuwait. The possibility of predicting each leadership component via emotional intelligence components was investigated for high and low achievers. A sample of 11th grade students from Kuwaiti…

  17. Causes of Nonattendance and Its Effect on Student Achievement at the High School Level

    Bracht, Kelly D.

    2010-01-01

    Many high schools in America have issues with student nonattendance. The researcher designed this mixed methods study to determine the affect of nonattendance on student achievement and to ascertain whether home-related factors or school-related factors were more significant causes of nonattendance. Both the high school in this study and other…

  18. Mathematics Achievement with Digital Game-Based Learning in High School Algebra 1 Classes

    Ferguson, Terri Lynn Kurley

    2014-01-01

    This study examined the impact of digital game-based learning (DGBL) on mathematics achievement in a rural high school setting in North Carolina. A causal comparative research design was used in this study to collect data to determine the effectiveness of DGBL in high school Algebra 1 classes. Data were collected from the North Carolina…

  19. Study-Orientation of High and Low Academic Achievers at Secondary Level in Pakistan

    Sarwar, Muhammad; Bashir, Muhammad; Khan, Muhammad Naemullah; Khan, Muhammad Saeed

    2009-01-01

    The study orientation of low and high academic achievers was compared, measured through a self-developed study orientation scale (SOS) primarily based on 47 items comparing study habits and attitude. Students' marks obtained in the 10th grade Examination determined the measure of academic performance. The analysis revealed that the high achievers…

  20. Niche dynamics of shorebirds in Delaware Bay: Foraging behavior, habitat choice and migration timing

    Novcic, Ivana

    2016-08-01

    Niche differentiation through resource partitioning is seen as one of the most important mechanisms of diversity maintenance contributing to stable coexistence of different species within communities. In this study, I examined whether four species of migrating shorebirds, dunlins (Calidris alpina), semipalmated sandpipers (Calidris pusilla), least sandpipers (Calidris minutilla) and short-billed dowitchers (Limnodromus griseus), segregate by time of passage, habitat use and foraging behavior at their major stopover in Delaware Bay during spring migration. I tested the prediction that most of the separation between morphologically similar species will be achieved by differential migration timing. Despite the high level of overlap along observed niche dimensions, this study demonstrates a certain level of ecological separation between migrating shorebirds. The results of analyses suggest that differential timing of spring migration might be the most important dimension along which shorebird species segregate while at stopover in Delaware Bay. Besides differences in time of passage, species exhibited differences in habitat use, particularly least sandpipers that foraged in vegetated areas of tidal marshes more frequently than other species, as well as short-billed dowitchers that foraged in deeper water more often than small sandpipers did. Partitioning along foraging techniques was less prominent than segregation along temporal or microhabitat dimensions. Such ranking of niche dimensions emphasizes significance of temporal segregation of migratory species - separation of species by time of passage may reduce the opportunity for interspecific aggressive encounters, which in turn can have positive effects on birds' time and energy budget during stopover period.

  1. Disruption of foraging by a dominant invasive species to decrease its competitive ability.

    Fabian Ludwig Westermann

    Full Text Available Invasive species are a major threat to biodiversity when dominant within their newly established habitat. The globally distributed Argentine ant Linepithema humile has been reported to break the trade-off between interference and exploitative competition, achieve high population densities, and overpower nests of many endemic ant species. We have used the sensitivity of the Argentine ant to the synthetic trail pheromone (Z-9-hexadecanal to investigate species interactions for the first time. We predicted that disrupting Argentine ant trail following behaviour would reduce their competitive ability and create an opportunity for three other resident species to increase their foraging success. Argentine ant success in the control was reduced with increasing pheromone concentration, as predicted, but interactions varied among competing resident species. These behavioural variations provide an explanation for observed differences in foraging success of the competing resident species and how much each of these individual competitors can increase their foraging if the competitive ability of the dominant invader is decreased. The mechanism for the observed increase in resource acquisition of resident species appears to be a decrease in aggressive behaviour displayed by the Argentine ant, which may create an opportunity for other resident species to forage more successfully. Our demonstration of species interactions with trail pheromone disruption is the first known case of reduced dominance under a pheromone treatment in ants.

  2. The Impact of Including Children with Intellectual Disability in General Education Classrooms on the Academic Achievement of Their Low-, Average-, and High-Achieving Peers

    Sermier Dessemontet, Rachel; Bless, Gerard

    2013-01-01

    Background: This study aimed at assessing the impact of including children with intellectual disability (ID) in general education classrooms with support on the academic achievement of their low-, average-, and high-achieving peers without disability. Method: A quasi-experimental study was conducted with an experimental group of 202 pupils from…

  3. Intercropping of Cereals and Legumes for Forage Production

    Hamdollah ESKANDARI; Ghanbari, Ahmad; Abdollah JAVANMARD

    2009-01-01

    Cereals are high important in feeding ruminant animals for their high dry matter production and low cost. However, cereals forage is poor in protein content which shows their low quality and nutritive value. Regarding to high feed costs of protein supplementations, legumes can be used in livestock nutrition for their high protein content and, thus, providing cost saving. Since legumes have low dry matter yield, acceptable forage yield and quality can obtained from intercropping of cereals and...

  4. School factors affecting postsecondary career pursuits of high-achieving girls in mathematics and science

    Yoo, Hyunsil

    This study examined the influences of secondary school experiences of high-achieving girls in math and science on their postsecondary career pursuits in science fields. Specifically, using the National Education Longitudinal Study of 1988 (NELS:88), the study investigated how science class experiences in high school affect science career persistence of high-achieving girls over and above personal and family factors. Selecting the top 10% on the 8 th grade math and science achievement tests from two panel samples of 1988--1994 and 1988--2000, this study examined which science instructional experiences (i.e., lecture-oriented, experiment-oriented, and student-oriented) best predicted college major choices and postsecondary degree attainments in the fields of science after controlling for personal and family factors. A two-stage test was employed for the analysis of each panel sample. The first test examined the dichotomous career pursuits between science careers and non-science careers and the second test examined the dichotomous pursuits within science careers: "hard" science and "soft" science. Logistic regression procedures were used with consideration of panel weights and design effects. This study identified that experiment-oriented and student-oriented instructional practices seem to positively affect science career pursuits of high-achieving females, while lecture-oriented instruction negatively affected their science career pursuits, and that the longitudinal effects of the two positive instructional contributors to science career pursuits appear to be differential between major choice and degree attainment. This study also found that the influences of instructional practices seem to be slight for general females, while those for high-achieving females were highly considerable, regardless of whether negative or positive. Another result of the study found that only student-oriented instruction seemed to have positive effects for high-achieving males. In

  5. Achieving Both High Power and Energy Density in Electrochemical Supercapacitors with Nanoporous Graphene Materials

    Yang, Hao; Kannappan, Santhakumar; Pandian, Amaresh S.; Jang, Jae-Hyung; Lee, Yun Sung; Lu, Wu

    2013-01-01

    Supercapacitors, based on the fast ion transportation, are specialized to provide high power, long stability, and efficient energy storage with highly porous electrode materials. However, their low energy density and specific capacitance prevent them from many applications that require long duration. Using a scalable nanoporous graphene synthesis method involving a simple annealing process in hydrogen, here we show graphene supercapacitors capable of achieving a high energy density comparable...

  6. What leadership behaviors were demonstrated by the principal in a high poverty, high achieving elementary school?

    E. Hayet J. Woods

    2016-12-01

    Full Text Available Examined through the lens of leadership, were the behaviors of a principal as perceived by stakeholders. The following themes emerged: (1 Educating the Whole Child, with the subthemes: (a providing basic needs; (b academic interventions based on achievement data; (c an emphasis on reading; (d extended academic time; and (e relationships; and (2 Synergy of Expectations, with the subthemes: (a consistent student expectations; (b increased staff accountability; and (c community involvement. The researchers found that the principal by demonstrating behaviors as a change agent, a creator of vision, and a provider of necessary support and strategies, rather than adopting numerous programs, the school personnel were able to increase and sustain academic achievement of the students of poverty as well as their peers. Implications for principal practices, along with leadership preparatory programs are significant.

  7. Following Different Pathways: Social Integration, Achievement, and the Transition to High School.

    Langenkamp, Amy G

    2009-11-01

    This study expands research on an academic and social turning point for adolescents, the transition to high school, by analyzing how students' level of social integration into school can affect high school academic performance. Using nationally representative data, three different pathways emerged as students transition to high school, characterized by varying amounts of disruption and opportunity for new social relationships upon entering high school. Findings suggest that elements of middle school social integration, including teacher bonding, popularity, and extracurricular participation, affect academic achievement when students enter high school. However, the association between integration into school and academic performance appears to be contingent upon the pathway students follow. PMID:20664813

  8. Collective foraging in heterogeneous landscapes

    Bhattacharya, Kunal

    2013-01-01

    Animals foraging alone are hypothesized to optimize the encounter rates with resources through L\\'evy walks. However, the issue of how the interactions between multiple foragers influence their search efficiency is still not completely understood. To address this, we consider a model to study the optimal strategy for a group of foragers searching for targets distributed heterogeneously. In our model foragers move on a square lattice containing immobile but regenerative targets. At any instant a forager is able to detect only those targets that happen to be in the same site. However, we allow the foragers to have information about the state of other foragers. A forager who has not detected any target walks towards the nearest location, where another forager has detected a target, with probability $\\exp{\\left(-\\alpha d\\right)}$, where $d$ is the distance and $\\alpha$ is a parameter. The model reveals that neither overcrowding ($\\alpha\\to 0$) nor independent searching ($\\alpha\\to\\infty$) is beneficial for the gr...

  9. High IQ Is Sufficient to Explain the High Achievements in Math and Science of the East Asian Peoples

    Lynn, Richard

    2010-01-01

    It is argued that it is unnecessary to propose that Confucian values explain the high achievements in math and science of the North East Asian peoples, and that these can be satisfactorily and more parsimoniously be explained by their high IQs.

  10. Relative contribution of ruminal buffering systems to pH regulation in feedlot cattle fed either low- or high-forage diets.

    Chibisa, G E; Beauchemin, K A; Penner, G B

    2016-07-01

    The relative contribution of ruminal short-chain fatty acid (SCFA) absorption and salivary buffering to pH regulation could potentially change under different dietary conditions. Therefore, the objective of this study was to investigate the effects of altering the ruminal supply of rapidly fermentable carbohydrate (CHO) on absorptive function and salivation in beef cattle. Eight heifers (mean BW±SD=410±14 kg) were randomly allocated to two treatments in a crossover design with 37-day periods. Dietary treatments were barley silage at 30% low forage (LF) or 70% high forage (HF) of dietary dry matter (DM), with the remainder of the diet consisting of barley grain (65% or 25% on a DM basis) and a constant level (5%) of supplement. The LF and HF diets contained 45.3% and 30.9% starch, and 4.1% and 14.0% physically effective fiber (DM basis), respectively. Ruminal pH was continuously measured from day 17 to day 23, whereas ruminal fluid was collected on day 23 to determine SCFA concentration. Ruminal liquid passage rate was determined on day 23 using Cr-ethylenediaminetetraacetic acid. Eating or resting salivation was measured by collecting masticate (days 28 and 29) or saliva samples (days 30 and 31) at the cardia, respectively. On days 30 and 31, the temporarily isolated and washed reticulo-rumen technique was used to measure total, and Cl--competitive (an indirect measure of protein-mediated transport) absorption of acetate, propionate and butyrate. As a result of the higher dietary starch content and DM intake, the ruminal supply of rapidly fermentable CHO, total ruminal SCFA concentration (118 v. 95 mM; P<0.001) and osmolality (330 v. 306 mOsm/kg; P=0.018) were greater in cattle fed LF compared with HF. In addition, feeding LF resulted in a longer duration (2.50 v. 0.09 h/day; P=0.02) and a larger area (0.44 v. 0.01 (pH×h)/day; P=0.050) that pH was below 5.5. There was no diet effect on total and Cl--competitive absorption (mmol/h and %/h) of acetate, propionate

  11. Antecedent and Concurrent Psychosocial Skills That Support High Levels of Achievement within Talent Domains

    Olszewski-Kubilius, Paula; Subotnik, Rena F.; Worrell, Frank C.

    2015-01-01

    Motivation and emotional regulation are important for the sustained focused study and practice required for high levels of achievement and creative productivity in adulthood. Using the talent development model proposed by the authors as a framework, the authors discuss several important psychosocial skills based on the psychological research…

  12. Experiencing More Mathematics Anxiety than Expected? Contrasting Trait and State Anxiety in High Achieving Students

    Roos, A.-L.; Bieg, M.; Goetz, T.; Frenzel, A. C.; Taxer, J.; Zeidner, M.

    2015-01-01

    This study examined mathematics anxiety among high and low achieving students (N = 237, grades 9 and 10) by contrasting trait (habitual) and state (momentary) assessments of anxiety. Previous studies have found that trait anxiety measures are typically rated higher than state measures. Furthermore, the academic self-concept has been identified to…

  13. The Influence of Social Capital Factors on African-American and Hispanic High School Student Achievement

    Davis, Jacqueline L.

    2009-01-01

    The underachievement of African American and Hispanic students has been an ongoing problem for schools in the United States. The purpose of this investigation was to add to the existing body of knowledge concerning social capital of African American and Hispanic high school students' academic achievement. Using a nationally representative sample…

  14. The Role of the High School Principal in Improving Student Learning and Achievement

    Raines, Paula L.

    2012-01-01

    The purpose of this exploratory mixed-method correlational and interview study was to gain insights into how the school principal influences student learning and achievement by providing positive instructional leadership. Research has suggested the principal's role is highly significant in determining the quality of teaching and learning…

  15. One-to-One Computing and Student Achievement in Ohio High Schools

    Williams, Nancy L.; Larwin, Karen H.

    2016-01-01

    This study explores the impact of one-to-one computing on student achievement in Ohio high schools as measured by performance on the Ohio Graduation Test (OGT). The sample included 24 treatment schools that were individually paired with a similar control school. An interrupted time series methodology was deployed to examine OGT data over a period…

  16. Social Media Use, Loneliness, and Academic Achievement: A Correlational Study with Urban High School Students

    Neto, Roque; Golz, Nancy; Polega, Meaghan

    2015-01-01

    This study explored the association between social media use, loneliness, and academic achievement in high school students and identified the demographic characteristics associated with these three elements. This study also aimed to identify the percentage of variance in loneliness accounted for by social media use and GPA. Participants were 345…

  17. Actively Closing the Gap? Social Class, Organized Activities, and Academic Achievement in High School

    Morris, David S.

    2015-01-01

    Participation in Organized Activities (OA) is associated with positive behavioral and developmental outcomes in children. However, less is known about how particular aspects of participation affect the academic achievement of high school students from different social class positions. Using the Education Longitudinal Study of 2002, this study…

  18. The Relationship between Illinois School District Superintendent Longevity and High School Student Achievement

    Libka, Robert J.

    2012-01-01

    Frequent changes in school district superintendents may be having a detrimental impact on student achievement. Rapid changes in leadership today parallel the present (NCLB) era of high stakes state assessments. The goal of the study was to provide correlation research that would have a positive effect on school district management, superintendent…

  19. Being Labeled "Nerd": Factors that Influence the Social Acceptance of High-Achieving Students

    Rentzsch, Katrin; Schutz, Astrid; Schroder-Abe, Michela

    2011-01-01

    The present investigation addresses the question of whether certain factors can protect high-achieving students at risk for being labeled a nerd against devaluation. In 2 studies, 125 and 317 students from Grade 8 evaluated vignettes describing average students and students who were called "nerds." Results indicate that being modest about good…

  20. An Analysis of the Academic Achievement of Indian High School Students in Federal and Public Schools.

    Bass, Willard P.

    A longitudinal study was designed to determine whether there were significant differences in academic achievement between senior high American Indian students in Federal on-reservation, Federal off-reservation, public on-reservation, and public off-reservation schools. The purpose of the study was to gather a variety of data on psychological and…

  1. Emotional Intelligence and Academic Achievement of High School Students in Kanyakumari District

    Lawrence, A. S. Arul; Deepa, T.

    2013-01-01

    The objective of the study is to find the significant relationship between emotional intelligence and academic achievement of high school students with reference to the background variables. Survey method was employed. Two tools are used in this study namely self-made Trait Emotional Intelligence Questionnaire Short Form (TEIQue SF) and the…

  2. Communication Satisfaction, Organizational Citizenship Behavior and the Relationship to Student Achievement in High Schools

    Blanchard, Gayle A.

    2012-01-01

    This study used a correlational design that allowed the researcher to examine the relationship among communication satisfaction, organizational citizenship behaviors (OCB) and student achievement. High school teachers were surveyed from a convenience sample of 12 school districts in Arizona. Established instruments were used to survey…

  3. Brain Structure and Resting-State Functional Connectivity in University Professors with High Academic Achievement

    Li, Weiwei; Yang, Wenjing; Li, Wenfu; Li, Yadan; Wei, Dongtao; Li, Huimin; Qiu, Jiang; Zhang, Qinglin

    2015-01-01

    Creative persons play an important role in technical innovation and social progress. There is little research on the neural correlates with researchers with high academic achievement. We used a combined structural (regional gray matter volume, rGMV) and functional (resting-state functional connectivity analysis, rsFC) approach to examine the…

  4. The Effects of Alcohol Use on Academic Achievement in High School

    Balsa, Ana I.; Giuliano, Laura M.; French, Michael T.

    2011-01-01

    This paper examines the effects of alcohol use on high school students' quality of learning. We estimate fixed-effects models using data from the National Longitudinal Study of Adolescent Health. Our primary measure of academic achievement is the student's grade point average (GPA) abstracted from official school transcripts. We find that…

  5. The Impact of Reading Success Academy on High School Reading Achievement

    Burlison, Kelly; Chave, Josh

    2014-01-01

    The study explores the effectiveness of the Reading Success Academy on the reading achievement of the selected group of ninth-grade students in a comprehensive high school. We examine in what ways the Reading Success Academy may improve the reading proficiency rates and amount of reading growth of ninth-grade students. The results indicate that…

  6. Achieving High Performance in AC-Field Driven Organic Light Sources

    Junwei Xu; David L. Carroll; Smith, Gregory M.; Chaochao Dun; Yue Cui

    2016-01-01

    Charge balance in organic light emitting structures is essential to simultaneously achieving high brightness and high efficiency. In DC-driven organic light emitting devices (OLEDs), this is relatively straight forward. However, in the newly emerging, capacitive, field-activated AC-driven organic devices, charge balance can be a challenge. In this work we introduce the concept of gating the compensation charge in AC-driven organic devices and demonstrate that this can result in exceptional in...

  7. Achievement of public and non-Catholic private high school students within a matched sample

    Mead, Susan Virginia

    1987-01-01

    Over the past six years, analyses of the National Center for Education Statistics' High School and Beyond data have primarily focused on the differences in achievement between public and Catholic high school students. Valuable data on non-Catholic private school students have been virtually ignored. Based on a strategy proposed by Althauser and Rubin (1970), in this study non-Catholic private schools are matched with public schools similar in school average base year student ...

  8. The Effects of College Counseling on High-Achieving, Low-Income Students

    Avery, Christopher N.

    2009-01-01

    This paper reports the results of a pilot study, using a randomized controlled trial to provide college counseling to high-achieving students from relatively poor families. We followed 107 high school seniors through the college admissions process in 2006-2007; we selected 52 of these students at random, offering them ten hours of individualized college advising with a nearby college counselor. The counseling had little or no effect on college application quality, but does seem to have influe...

  9. Breeding tropical forages

    L Jank

    2011-01-01

    Full Text Available Brazil has the largest commercial beef cattle herd and is the main beef exporter in the world. Cultivated pastures arethe basis for the Brazilian beef production, and occupy an area of 101.4 million hectares. However, very few forage cultivars arecommercially available, and the majority of these are of apomictic reproduction, thus genetically homogeneous. Tropical foragebreeding is at its infancy, but much investment and efforts have been applied in the last three decades and some new cultivars havebeen released. In this paper, origin of different species, modes of reproduction, breeding programs and targets are discussed andthe resulting new cultivars released are presented.

  10. Movement patterns for a critically endangered species, the leatherback turtle (Dermochelys coriacea, linked to foraging success and population status.

    Helen Bailey

    Full Text Available Foraging success for pelagic vertebrates may be revealed by horizontal and vertical movement patterns. We show markedly different patterns for leatherback turtles in the North Atlantic versus Eastern Pacific, which feed on gelatinous zooplankton that are only occasionally found in high densities. In the Atlantic, travel speed was characterized by two modes, indicative of high foraging success at low speeds (<15 km d(-1 and transit at high speeds (20-45 km d(-1. Only a single mode was evident in the Pacific, which occurred at speeds of 21 km d(-1 indicative of transit. The mean dive depth was more variable in relation to latitude but closer to the mean annual depth of the thermocline and nutricline for North Atlantic than Eastern Pacific turtles. The most parsimonious explanation for these findings is that Eastern Pacific turtles rarely achieve high foraging success. This is the first support for foraging behaviour differences between populations of this critically endangered species and suggests that longer periods searching for prey may be hindering population recovery in the Pacific while aiding population maintenance in the Atlantic.

  11. Implementation and control of electrolysers to achieve high penetrations of renewable power

    Troncoso, E.; Newborough, M. [ITM Power plc, Orkney House, Great Chesterford Court, Great Chesterford, Saffron Walden CB10 1PF (United Kingdom)

    2007-09-15

    The mass deployment of electrolysers, within a power system serving a region of high wind resource, as the enabling mechanism for achieving five key objectives is assessed (that is: a very high installed capacity of wind power plant (WPP); zero wind curtailment during times of low demand; a very high load factor for thermal power plant; an electricity supply of low-carbon intensity; and a hydrogen supply of low-carbon intensity). Three electrolyser implementation cases were simulated for three days characterised mainly by wind availability and emphasis was placed on maximizing the smoothness of the load profile (LF) applied to thermal power plant. If zero-carbon hydrogen is to be produced a daily load factor for thermal power plant of 90% is the upper limit, but load factors of up to 100% are achievable if a carbon intensity of 3kgCO{sub 2}/kgH{sub 2} is permitted. For wind penetrations exceeding approximately 30% of system maximum demand, the electrolyser stock must include implementations close to WPP if curtailment is to be avoided. To achieve very high wind penetrations and very high load factors for thermal power plant requires a large stock of electrolysers - for the system investigated approximately 1.1 MW of electrolyser capacity is required per installed MW of wind power. (author)

  12. Achievement Motivation of the High School Students: A Case Study among Different Communities of Goalpara District of Assam

    Sarangi, C.

    2015-01-01

    Achievement motivation is a consistent striving force of an individual to achieve success to a certain standard of excellence in competing situation. In this study an attempt was made to study the effect of achievement motivation on the academic achievement of the high school students of tribal and non tribal communities in relation to their sex…

  13. The role of chronotype, gender, test anxiety, and conscientiousness in academic achievement of high school students.

    Rahafar, Arash; Maghsudloo, Mahdis; Farhangnia, Sajedeh; Vollmer, Christian; Randler, Christoph

    2016-01-01

    Previous findings have demonstrated that chronotype (morningness/intermediate/eveningness) is correlated with cognitive functions, that is, people show higher mental performance when they do a test at their preferred time of day. Empirical studies found a relationship between morningness and higher learning achievement at school and university. However, only a few of them controlled for other moderating and mediating variables. In this study, we included chronotype, gender, conscientiousness and test anxiety in a structural equation model (SEM) with grade point average (GPA) as academic achievement outcome. Participants were 158 high school students and results revealed that boys and girls differed in GPA and test anxiety significantly, with girls reporting better grades and higher test anxiety. Moreover, there was a positive correlation between conscientiousness and GPA (r = 0.17) and morningness (r = 0.29), respectively, and a negative correlation between conscientiousness and test anxiety (r = -0.22). The SEM demonstrated that gender was the strongest predictor of academic achievement. Lower test anxiety predicted higher GPA in girls but not in boys. Additionally, chronotype as moderator revealed a significant association between gender and GPA for evening types and intermediate types, while intermediate types showed a significant relationship between test anxiety and GPA. Our results suggest that gender is an essential predictor of academic achievement even stronger than low or absent test anxiety. Future studies are needed to explore how gender and chronotype act together in a longitudinal panel design and how chronotype is mediated by conscientiousness in the prediction of academic achievement. PMID:26651154

  14. High fat diet promotes achievement of peak bone mass in young rats

    Malvi, Parmanand; Piprode, Vikrant; Chaube, Balkrishna; Pote, Satish T. [National Centre for Cell Science, Savitribai Phule Pune University Campus, Ganeshkhind, Pune 411 007 (India); Mittal, Monika; Chattopadhyay, Naibedya [Division of Endocrinology and Center for Research in Anabolic Skeletal Targets in Health and Illness (ASTHI), CSIR-Central Drug Research Institute, Jankipuram Extension, Sitapur Road, Lucknow 226 031 (India); Wani, Mohan R. [National Centre for Cell Science, Savitribai Phule Pune University Campus, Ganeshkhind, Pune 411 007 (India); Bhat, Manoj Kumar, E-mail: manojkbhat@nccs.res.in [National Centre for Cell Science, Savitribai Phule Pune University Campus, Ganeshkhind, Pune 411 007 (India)

    2014-12-05

    Highlights: • High fat diet helps in achieving peak bone mass at younger age. • Shifting from high fat to normal diet normalizes obese parameters. • Bone parameters are sustained even after withdrawal of high fat diet. - Abstract: The relationship between obesity and bone is complex. Epidemiological studies demonstrate positive as well as negative correlation between obesity and bone health. In the present study, we investigated the impact of high fat diet-induced obesity on peak bone mass. After 9 months of feeding young rats with high fat diet, we observed obesity phenotype in rats with increased body weight, fat mass, serum triglycerides and cholesterol. There were significant increases in serum total alkaline phosphatase, bone mineral density and bone mineral content. By micro-computed tomography (μ-CT), we observed a trend of better trabecular bones with respect to their microarchitecture and geometry. This indicated that high fat diet helps in achieving peak bone mass and microstructure at younger age. We subsequently shifted rats from high fat diet to normal diet for 6 months and evaluated bone/obesity parameters. It was observed that after shifting rats from high fat diet to normal diet, fat mass, serum triglycerides and cholesterol were significantly decreased. Interestingly, the gain in bone mineral density, bone mineral content and trabecular bone parameters by HFD was retained even after body weight and obesity were normalized. These results suggest that fat rich diet during growth could accelerate achievement of peak bone mass that is sustainable even after withdrawal of high fat diet.

  15. High fat diet promotes achievement of peak bone mass in young rats

    Highlights: • High fat diet helps in achieving peak bone mass at younger age. • Shifting from high fat to normal diet normalizes obese parameters. • Bone parameters are sustained even after withdrawal of high fat diet. - Abstract: The relationship between obesity and bone is complex. Epidemiological studies demonstrate positive as well as negative correlation between obesity and bone health. In the present study, we investigated the impact of high fat diet-induced obesity on peak bone mass. After 9 months of feeding young rats with high fat diet, we observed obesity phenotype in rats with increased body weight, fat mass, serum triglycerides and cholesterol. There were significant increases in serum total alkaline phosphatase, bone mineral density and bone mineral content. By micro-computed tomography (μ-CT), we observed a trend of better trabecular bones with respect to their microarchitecture and geometry. This indicated that high fat diet helps in achieving peak bone mass and microstructure at younger age. We subsequently shifted rats from high fat diet to normal diet for 6 months and evaluated bone/obesity parameters. It was observed that after shifting rats from high fat diet to normal diet, fat mass, serum triglycerides and cholesterol were significantly decreased. Interestingly, the gain in bone mineral density, bone mineral content and trabecular bone parameters by HFD was retained even after body weight and obesity were normalized. These results suggest that fat rich diet during growth could accelerate achievement of peak bone mass that is sustainable even after withdrawal of high fat diet

  16. Personality, foraging and fitness consequences in a long lived seabird.

    Samantha C Patrick

    Full Text Available While personality differences in animals are defined as consistent behavioural variation between individuals, the widely studied field of foraging specialisation in marine vertebrates has rarely been addressed within this framework. However there is much overlap between the two fields, both aiming to measure the causes and consequences of consistent individual behaviour. Here for the first time we use both a classic measure of personality, the response to a novel object, and an estimate of foraging strategy, derived from GPS data, to examine individual personality differences in black browed albatross and their consequences for fitness. First, we examine the repeatability of personality scores and link these to variation in foraging habitat. Bolder individuals forage nearer the colony, in shallower regions, whereas shyer birds travel further from the colony, and fed in deeper oceanic waters. Interestingly, neither personality score predicted a bird's overlap with fisheries. Second, we show that both personality scores are correlated with fitness consequences, dependent on sex and year quality. Our data suggest that shyer males and bolder females have higher fitness, but the strength of this relationship depends on year quality. Females who forage further from the colony have higher breeding success in poor quality years, whereas males foraging close to the colony always have higher fitness. Together these results highlight the potential importance of personality variation in seabirds and that the fitness consequences of boldness and foraging strategy may be highly sex dependent.

  17. PRODUCTIVE IMPACT OF THE GREEN FORAGE SUPPLY USAGE AT THE DAIRY FARMS

    LAVINIA MOISE

    2013-12-01

    Full Text Available This paper presents the importance of the crop structure as a tool to maximize efficiency in the conceiving of the green forage supply scheme in a dairy farm. Several apects are necessary to consider for proper green forage utilization by the cattle, as follows: climatic conditions, proper field operations for each crop, optimal harvest date, and farm technical and economical resources. With a high degree of succulence, green forage and derived products (silage, haylage, present addvantages as compared to hay, having superior indices of nutritive value and palatability. A green forage supply scheme was applied on an area of 188 ha taking into account dairy cattle biological traits. Crop structure was as follows: forage maize, Sudan grass, Italian ryegrass, new lucern and old lucerne, and orchardgrass. Insuring the required superior green forage for the dairy cattle according to forage rations, represents one of the main techniques to maximize milk production and to minimize milk production cost.

  18. The Effect of High Stakes High School Achievement Awards : Evidence from a School-Centered Randomized Trial

    Angrist, Joshua D.; Lavy, Victor

    2004-01-01

    In many countries, college-bound high school seniors must pass a test or series of tests. In Israel, this requirement is known as the ?Bagrut?, or matriculation certificate, obtained by passing a series of subject tests. In spite of the Bagrut?s value, Israeli society is marked by vast differences in Bagrut rates by region and socioeconomic status. We attempted to increase the likelihood of Bagrut certification among low-achieving students by offering substantial cash incentives to high schoo...

  19. Goal Setting: Enhancing Academic Attitudes and Achievement in High School Gifted Underachievers

    Sivaraman, Rhonda Czapla

    2012-01-01

    The underachievement of gifted students is a well-documented problem in educational research. This study employed an experimental design to determine whether an existing personal goal setting intervention could successfully improve academic attitudes and achievement in a sample of 44 high school gifted underachievers, as well as determine if any patterns existed in students' goal writing exercises. The goal setting intervention included two after-school goal setting sessions for a duration ...

  20. RELATIONSHIP BETWEEN PARENTAL RESTRAINTS, EMOTIONAL INTELLIGENCE AND ACADEMIC ACHIEVEMENT AMONG RURAL HIGH SCHOOL GIRLS

    Sushma H.B; Surekha Ksheerasagar

    2014-01-01

    This study investigated the relationship among parental restraints on emotional intelligence and academic achievement of 60 high school going pre-adolescent girls (30 Kannada Medium and 30 English Medium) of rural areas of Gulbarga district. The participants ranged in age between 11 to 17years. Two hypotheses were tested for significance at 0.05 margin in error. The main objective of the study is to find the relationship between parental restraints on emotional intelligence an...

  1. What Makes a Good Program? A Case Study of a School Admitting High Academic Achievers

    Ching Man Lam

    2008-01-01

    This paper reports the results of a qualitative study that explored the administration and implementation of the Tier 1 Program (Secondary 1 Curriculum) of the Project P.A.T.H.S. The case study method was used to explore perceptions of the teachers and the project coordinator of program effectiveness, and to identify various factors for program success. A school admitting high academic achievers was selected, and site visits, as well as individual and focus group interviews, were conducted wi...

  2. Resilience influence, goals and social context in the academic achievement of high school students

    José Concepción Gaxiola Romero; Sandybell González Lugo; Zita Guadalupe Contreras Hernández

    2012-01-01

    The academic achievement in high school students of Mexico, according to national and international evaluations has been insufficient. In spite of this situation, is possible to find excellent students, even in the context of sharing negative contextual and physical conditions. There are few investigations that describe the variables associated to resilient students. The alumni that are beyond the risks are called resilient (Rutter, 2007). The aim of this research was to explore and identify ...

  3. A new Methodology for achieving MMIC Bandpass Active Filters at High Frequencies

    Darcel, L.; Duême, P.; Funck, R.; Alquié, G.

    2004-01-01

    This paper presents a new methodology based on actively coupled resonators, for achieving microwave active filters. In this method, which lends itself to narrowband and wideband filtering applications, we associate core cells with different resonance frequencies, adjusted separately, to synthesise a Butterworth, Chebyshev or other all-pole approximation. Two 1-pole bandpass filters centred at 9GHz, with 3dB bandwidth of 500 MHz, high gain of 17 dB and 21 dB, including ...

  4. AN ENERGY MODEL FOR ACHIEVING HIGH PERFORMANCE BURST TRANSMISSION IN OBCS NETWORKS

    Renuka, R.; Kavitha, V.

    2013-01-01

    Optical burst switching is a promising solution for all optical WDM networks. It combines the benefits of optical circuit switching and optical packet switching. In OBS, the user data is collected at the edge of the network, sorted based on the destination address and grouped into variable size bursts. The OBS framework has been widely used in past years, for recent work use Optical Burst Chain switching (OBCS) to achieve high performance. Here switching unit is burst chain it consist of non-...

  5. Forage yield and nitrogen nutrition dynamics of warm-season native forage genotypes under two shading levels and in full sunlight

    Raquel Santiago Barro

    2012-07-01

    Full Text Available The successful achievement of a highly productive understorey pasture in silvopastoral systems depends on the use of well-adapted forage genotypes, showing good agronomic performance and persistence under shading and grazing. In this study, the herbage dry matter yield (DMY and nitrogen nutrition dynamics were determined in three native warm-season grasses (Paspalum regnellii, Paspalum dilatatum and Paspalum notatum and a forage legume (Arachis pintoi under two shading levels compared with full sun. The experiment was conducted in the Campanha region, Bagé, state of Rio Grande do Sul, Brazil, during two evaluation cycles (2008/2009 and 2009/2010. Three shade cloth levels (0%, 50% and 80% of light restriction were applied to the forage genotypes in a split plot design, in which shading levels were the main plot and forage genotypes were the subplots, with three replications. P. regnellii showed the highest accumulated DMY (1500 and 1700 g m-2, respectively, for the first and second evaluation cycles at all shading levels and showed no DMY decreased under the heavy shade (80%. Average DMY over the four genotypes under the 50% shade level was higher or equal compared with full sun. Influence of rainfall was observed on the DMY performance of all genotypes: the positive effect of moderate shading (50% on P. dilatatum and P. notatum DMY was associated to a low soil water availability status. Increased shading level resulted in high nitrogen nutrition index values on grasses, in comparison with full sun. All genotypes performed well under the moderate shading level, but the DMY of both P. regnellii and P. dilatatum and the herbage N content in P. notatum and A. pintoi of all genotypes stood out, showing that those main genotypes are promising to grow in silvopastoral systems at the Campanha region in southern Brazil.

  6. High-fidelity simulation: Assessment of student nurses' team achievements of clinical judgment.

    Hallin, Karin; Bäckström, Britt; Häggström, Marie; Kristiansen, Lisbeth

    2016-07-01

    Nursing educators have the challenge of preparing nursing students to handle complex patient care situations in real life, but much remains unknown about the ability to make clinical judgments. In this study, high-fidelity simulation (HFS) was used at a Swedish university to find answers about pre-licensure nursing students' success in clinical judgment in terms of team ability and relationships with theoretical achievements, and personal and scenario circumstances. The matrix Lasater Clinical Judgment Rubric (LCJR) was used to analyze and score the students' ability in teams to notice, interpret and respond to complex care situations. Overall, the results showed the student teams in their first meeting with HFS in a complex care situation achieved low clinical judgment points; most teams were in the stages of Beginning and Developing. For attaining high team achievements the majority of the students in the team should theoretically be "high performance". Being observers and having HFS experience before nursing education was significant too. However, age, health care experience, and assistant nurse degrees were of secondary importance. Further research at universities regionally, nationally, and internationally is needed. PMID:27428686

  7. Attention in Urban Foraging

    Malcolm McCullough

    2013-05-01

    Full Text Available This position paper argues how there has to be much more to smart city learning than just wayshowing, and something better as augmented reality than covering the world with instructions. Attention has become something for many people to know better in an age of information superabundance. Embodied cognition explains how the work-ings of attention are not solely a foreground task, as if attention is something to pay. As digital media appear in ever more formats and contexts, their hybrids with physical form increasing influence how habitual engagement with persistent situations creates learning. Ambient information can just add to the distraction by multitasking, or it can support more favorable processes of shifting among different kinds of information with a particular intent. As one word for this latter process, foraging deserves more consideration in smart city learning

  8. Radiation and temperature influence on forage grasses yield

    Biomass production has been studied in forage plants, as well as the temperature and radiation effects on plant growth. Four cultivars of grasses: Lolium multiflorum var westerwoldicum cv Promenade, Lolium perenne cvs Combi and Compas and Bromus inermis were growing as microswards in a growth chamber with constant temperature and outdoors. A field assay was done also with the same cultivars. L. multiflorum was the highest productive genotype anywhere showing also more active growth at low temperatures. Total production showed significant differences among genotypes. It was also a clear correspondence among microswards and field productions. Highest efficiency values (in % of PAR accumulated as dry matter) was obtained in 6th cut (April) achieving to 5.18 % in L. multiflorum. Biomass production variations through the growth period show a low correlation with <> and very high correlation with total irradiation received by the sward between consecutive cuts

  9. The Effect of English Learning Anxiety on Iranian High-School Students’ English Language Achievement

    Sara Atef-Vahid

    2011-10-01

    Full Text Available The present study explored English language learning anxiety among 38 third-year high school students in English classrooms and its relationship with overall English achievement. Students’ foreign language anxiety was surveyed and analyzed using the Foreign Language Classroom Anxiety Scale (Horwitz, Horwitz, & Cope, 1986 [14] and their English achievement was measured through their final standardized English exam administered by the school. The results showed that although some students felt extremely confident and relaxed, however, one-third of the
    students experienced moderate to high-anxiety levels while learning the English language in class. Correlational analysis revealed that the total FLCAS scores had a significantly moderate negative correlation (r=-.0586, p<.01 with the total final English exams scores of the participants. Anxiety was also analyzed according to the four different variables of anxiety (communication anxiety, test anxiety, fear of negative evaluation, English classroom anxiety which were measured by the FLCAS. The results of the Pearson correlational analysis indicated that English achievement was modestly correlated with all four anxiety variables (p<0.01. Of the four types of anxiety, English Classroom anxiety had the highest correlational value. Finally, possible anxiety provoking factors
    leading to these findings are examined and discussed, and some pedagogical implications are proposed.

  10. Achieving High Contrasts Through Speckle Rejection With Slicer Based Integral Field Spectrographs

    Salter, Graeme; Thatte, Niranjan; Tecza, Matthias; Clarke, Fraser

    2011-09-01

    Speckle noise, not photon noise, remains to be the limiting factor in the direct detection of high contrast companions. With studies for the future exo-planet characterisation and imaging instruments on the ELTs under way, the correct choice of technology must be made that will enable the fitting and removal of the speckle noise that remains after AO. We conclusively demonstrate, through the use of an experimental setup producing a simulated speckle, that slicer based integral field spectrographs (IFS) and post-processing using spectral deconvolution can achieve speckle rejection factors of 1000 in broad band reconstructed images (and 100 per spectral channel). This represents an order of magnitude improvement over current state-of-the-art. Contrary to popular belief, we do not find any evidence that this choice of IFS technology limits the achievable contrast of extra solar planet direct detection instruments. Coupled with extreme adaptive optics systems and high performance coronagraphs, a slicer based integral field spectrograph can achieve contrasts exceeding 10^9, making it an attractive option for the next generation of instruments being designed for the direct detection of extra solar planets (e.g. EPICS for the E-ELT).

  11. Strategies to achieve high-solids enzymatic hydrolysis of dilute-acid pretreated corn stover.

    Geng, Wenhui; Jin, Yongcan; Jameel, Hasan; Park, Sunkyu

    2015-01-01

    Three strategies were presented to achieve high solids loading while maximizing carbohydrate conversion, which are fed-batch, splitting/thickening, and clarifier processes. Enzymatic hydrolysis was performed at water insoluble solids (WIS) of 15% using washed dilute-acid pretreated corn stover. The carbohydrate concentration increased from 31.8 to 99.3g/L when the insoluble solids content increased from 5% to 15% WIS, while the final carbohydrate conversion was decreased from 78.4% to 73.2%. For the fed-batch process, a carbohydrate conversion efficiency of 76.8% was achieved when solid was split into 60:20:20 ratio, with all enzymes added first. For the splitting/thickening process, a carbohydrate conversion of 76.5% was realized when the filtrate was recycled to simulate a steady-state process. Lastly, the clarifier process was evaluated and the highest carbohydrate conversion of 81.4% was achieved. All of these results suggests the possibility of enzymatic hydrolysis at high solids to make the overall conversion cost-competitive. PMID:25836373

  12. The effects of modeling instruction on high school physics academic achievement

    Wright, Tiffanie L.

    The purpose of this study was to explore whether Modeling Instruction, compared to traditional lecturing, is an effective instructional method to promote academic achievement in selected high school physics classes at a rural middle Tennessee high school. This study used an ex post facto , quasi-experimental research methodology. The independent variables in this study were the instructional methods of teaching. The treatment variable was Modeling Instruction and the control variable was traditional lecture instruction. The Treatment Group consisted of participants in Physical World Concepts who received Modeling Instruction. The Control Group consisted of participants in Physical Science who received traditional lecture instruction. The dependent variable was gains scores on the Force Concepts Inventory (FCI). The participants for this study were 133 students each in both the Treatment and Control Groups (n = 266), who attended a public, high school in rural middle Tennessee. The participants were administered the Force Concepts Inventory (FCI) prior to being taught the mechanics of physics. The FCI data were entered into the computer-based Statistical Package for the Social Science (SPSS). Two independent samples t-tests were conducted to answer the research questions. There was a statistically significant difference between the treatment and control groups concerning the instructional method. Modeling Instructional methods were found to be effective in increasing the academic achievement of students in high school physics. There was no statistically significant difference between FCI gains scores for gender. Gender was found to have no effect on the academic achievement of students in high school physics classes. However, even though there was not a statistically significant difference, female students' gains scores were higher than male students' gains scores when Modeling Instructional methods of teaching were used. Based on these findings, it is recommended

  13. Biological conversion of forage sorghum biomass to ethanol by steam explosion pretreatment and simultaneous hydrolysis and fermentation at high solid content

    Manzanares, Paloma; Ballesteros, Ignacio; Negro, Maria Jose; Oliva, Jose Miguel; Gonzalez, Alberto; Ballesteros, Mercedes [Renewable Energy Department-CIEMAT, Biofuels Unit, Madrid (Spain)

    2012-06-15

    In this work, forage sorghum biomass was studied as feedstock for ethanol production by a biological conversion process comprising the steps of hydrothermal steam explosion pretreatment, enzymatic hydrolysis with commercial enzymes, and fermentation with the yeast Saccharomyces cerevisiae. Steam explosion conditions were optimized using a response surface methodology considering temperature (180-230 C) and time (2-10 min). Sugar recovery in the pretreatment and the enzymatic digestibility of the pretreated solid were used to determine the optimum conditions, i.e., 220 C and 7 min. At these conditions, saccharification efficiency attained 89 % of the theoretical and the recovery of xylose in the prehydrolyzate accounted for 35 % of the amount of xylose present in raw material. Then, a simultaneous hydrolysis and fermentation (SSF) process was tested at laboratory scale on the solid fraction of forage sorghum pretreated at optimum condition, in order to evaluate ethanol production. The effect of the enzyme dose and the supplementation with xylanase enzyme of the cellulolytic enzyme cocktail was studied at increasing solid concentration up to 18 % (w/w) in SSF media. Results show good performance of SSF in all consistencies tested with a significant effect of increasing enzyme load in SSF yield and final ethanol concentration. Xylanase supplementation allows increasing solid concentration up to 18 % (w/w) with good SSF performance and final ethanol content of 55 g/l after 4-5 days. Based on this result, about 190 l of ethanol could be obtained from 1 t of untreated forage sorghum, which means a transformation yield of 85 % of the glucose contained in the feedstock. (orig.)

  14. Alfalfa (Medicago Sativa L As A Promising Forage In Indonesia

    Sajimin

    2011-06-01

    Full Text Available Alfalfa (Medicago sativa L or Lucerne is a perennial herbaceous legume with superior forage quality. It is the most important forage crop in the world and it was the first domesticated forage crop. Alfalfa is able to fix nitrogen from the air through a symbiotic relationship with Rhizobium bacteria with N production 7.85 – 10.37 g/m2. Its rooting system can reach 4.5 m that allows it to escape drought. Forage production can reach 15.48 tons of dry matter per ha/year and containing 18.0 – 29.1 % crude protein. Plants can live 3 to 12 years depending on climatic conditions and crop varieties. However, alfalfa is not a tropical plant, thus it has not been widely cultivated in Indonesia. The problem of alfalfa cultivation are high pest attacks and competition with weeds. Therefore, alfalfa cultivation requires attention and good management to obtain optimum yield.

  15. Information flow and regulation of foraging activity in bumble bees (Bombus spp.)

    Dornhaus, Anna; Chittka, Lars

    2004-01-01

    Communication in the context of foraging in bumble bees has received less attention than in other social bees. Yet, recent studies have revealed that information flow mediates colony foraging activity. The species studied do not recruit to specific locations, but bees can learn the scent of food sources at the nest, which may reduce their search time. Location communication may not confer high benefits to bumble bees. But bees react to nectar influx with increased foraging activity, with high...

  16. Hmong Parental Involvement and Support: A Comparison Between Families of High and Low Achieving High School Seniors

    Katherine Green

    2009-01-01

    Full Text Available The Hmong are some of the newest refugees who have settled in the United States with population estimates around 300,000. Unfortunately research has shown many Hmong children are not as successful in their education as their peers. Parental involvement in education has consistently been shown to impact academic success and attendance in higher education programs. Little is known about Hmong parental involvement in their children’s education process. Therefore, this study was done to compare and contrast the general family characteristics, parenting methods, parental involvement philosophies, parental involvement experiences, and parental education expectations in Hmong families of high school seniors classified as either high academic achievers or low achievers. Students were classified into either higher or lower academic achievement groups based on their high school cumulative GPA. Five students were randomly selected for each group and a qualitative research interview method was used to interview the students and both of their parents (n=30. The findings showed the parents of the higher academic achieving students were younger, had higher levels of education, and had better relationships and trust with the students. Parents from both groups did not have any written rules for their children to follow at home, they mainly became involved in their children’s education during the elementary and middle school years, and they did not have any specific preference of an educational level, career, or school for their children after high school. Recommendations for ways Hmong families can be encouraged to participate more in education are made.

  17. Depletion of selenium in whole blood, liver and muscle tissue of beef heifers that had previously grazed forages containing high amounts of selenium

    time after grazing (P < 0.01), but the rates of Se mobilization from blood, liver and muscle differed. Even though the concentration of Se in liver was 25% higher in TWG heifers at the end of grazing, after 20 d of being fed a diet with lower levels of Se, both groups had similar concentrations of Se in liver (i.e., 0.92 vs. 0.85 mg/kg), demonstrating that mobilization of Se that had accumulated in liver occurred quickly. The Se concentration in blood decreased at a much slower rate than in liver, possibly because Se mobilized from liver and muscle continuously entered the blood pool. At 81 d of post-grazing feeding, concentrations of Se were reduced by 77% in liver, 49% in blood, but only 31% in muscle. Overall, muscle tissue had the slowest rate of Se mobilization after grazing high Se pastures, but it is the largest pool of Se in the body. The differences in the muscle Se content for CWR and TWG grazed heifers also demonstrate that the content of Se in forage is critical to maximizing Se levels in muscle. Beef production systems that target marketing of Se enriched beef may have to rely on feeding strategies that allow finishing of cattle in no more than 60 d after Se loading, but ideally in as short a time as possible

  18. Achieving High Performance Distributed System: Using Grid, Cluster and Cloud Computing

    Sunil Kr Singh

    2015-02-01

    Full Text Available To increase the efficiency of any task, we require a system that would provide high performance along with flexibilities and cost efficiencies for user. Distributed computing, as we are all aware, has become very popular over the past decade. Distributed computing has three major types, namely, cluster, grid and cloud. In order to develop a high performance distributed system, we need to utilize all the above mentioned three types of computing. In this paper, we shall first have an introduction of all the three types of distributed computing. Subsequently examining them we shall explore trends in computing and green sustainable computing to enhance the performance of a distributed system. Finally presenting the future scope, we conclude the paper suggesting a path to achieve a Green high performance distributed system using cluster, grid and cloud computing

  19. Achieving High Performance in AC-Field Driven Organic Light Sources

    Xu, Junwei; Carroll, David L.; Smith, Gregory M.; Dun, Chaochao; Cui, Yue

    2016-04-01

    Charge balance in organic light emitting structures is essential to simultaneously achieving high brightness and high efficiency. In DC-driven organic light emitting devices (OLEDs), this is relatively straight forward. However, in the newly emerging, capacitive, field-activated AC-driven organic devices, charge balance can be a challenge. In this work we introduce the concept of gating the compensation charge in AC-driven organic devices and demonstrate that this can result in exceptional increases in device performance. To do this we replace the insulator layer in a typical field-activated organic light emitting device with a nanostructured, wide band gap semiconductor layer. This layer acts as a gate between the emitter layer and the voltage contact. Time resolved device characterization shows that, at high-frequencies (over 40 kHz), the semiconductor layer allows for charge accumulation in the forward bias, light generating part of the AC cycle and charge compensation in the negative, quiescent part of the AC cycle. Such gated AC organic devices can achieve a non-output coupled luminance of 25,900 cd/m2 with power efficiencies that exceed both the insulator-based AC devices and OLEDs using the same emitters. This work clearly demonstrates that by realizing balanced management of charge, AC-driven organic light emitting devices may well be able to rival today’s OLEDs in performance.

  20. Number Sense-Based Strategies Used by High-Achieving Sixth Grade Students Who Experienced Reform Textbooks

    Alsawaie, Othman N.

    2012-01-01

    The purpose of this study was to explore strategies used by high-achieving 6th grade students in the United Arab Emirates (UAE) to solve basic arithmetic problems involving number sense. The sample for the study consisted of 15 high-achieving boys and 15 high-achieving girls in grade 6 from 2 schools in the Emirate of Abu Dhabi, UAE. Data for the…

  1. Cognitive abilities and motivational processes in high school students' science achievement and engagement

    Lau, Shun

    The dissertation presents two analytic approaches, a variable-centered and person-centered approach, to investigating holistic patterns of the cognitive, motivational, and affective correlates of science achievement and engagement in a sample of 491 10th and 11th grade high-school students. Building on Snow's (1989) idea of two pathways to achievement outcomes, Study 1 adopted a variable-centered approach to examining how cognitive and motivational factors associated with the performance and commitment pathways, respectively, contributed to the prediction of achievement outcomes in science. Results of hierarchical regression analyses showed that (a) students' cognitive abilities were the strongest predictors of their performance in science as measured by standardized test scores; (b) motivational processes enhanced the predictive validity for science test scores and grades beyond the variance accounted for by ability and demography; (c) motivational processes were the strongest predictors of students' commitment to science in the form of situational engagement and anticipated choices of science-related college majors and careers; and (d) competence beliefs served as a point of contact between the performance and commitment pathways. These results are consistent with Snow's (1989) conjecture that both performance and commitment pathway-related factors are necessary for understanding the full range of person-level inputs to achievement outcomes. Study 2 adopted a person-centered approach to examining holistic organizations of psychological factors within individuals and their relations to science achievement and engagement. Four types of students characterized by unique configurations of cognitive, motivational, and affective attributes were identified in both the male and female subsamples using inverse factor analysis. Type membership was found to distinguish students in various indicators of science achievement and engagement. Two of the four types were also found

  2. Students High Achievement on Learning Style Preferences in Chinese Department, Binus University

    Yetty Go

    2015-02-01

    every student has her/his own individual way to resolve their problems in learning. In learning process, students individual differences exist. These differences lead to different learning speed and learning style of the student. The purpose of this study was to investigate the high achievement students learning styles. This study was based on Reids learning styles theory and also uses Reids Perceptual Learning Style Preference Questionnaire (PLSPQ to investigate students learning styles. The main finding of this study is that students learning style preference is group style. According to student learning style preferences results, students prefer to learn together with others or in group and learn in a more interactive way.

  3. AN ENERGY MODEL FOR ACHIEVING HIGH PERFORMANCE BURST TRANSMISSION IN OBCS NETWORKS

    R.RENUKA

    2013-04-01

    Full Text Available Optical burst switching is a promising solution for all optical WDM networks. It combines the benefits of optical circuit switching and optical packet switching. In OBS, the user data is collected at the edge of the network, sorted based on the destination address and grouped into variable size bursts. The OBS framework has been widely used in past years, for recent work use Optical Burst Chain switching (OBCS to achieve high performance. Here switching unit is burst chain it consist of non-periodic bursts in one wavelength. We present extensive simulation result for throughput, delay and energy to demonstrate its superior performance over OBS networks.

  4. Corn in consortium with forages

    Cássia Maria de Paula Garcia; Marcelo Andreotti; Marcelo Carvalho Minhoto Teixeira Filho; Keny Samejima Mascarenha Lopes; Ciniro Costa; Erikelly Aline Ribeiro de Santana

    2013-01-01

    The basic premises for sustainable agricultural development with focus on rural producers are reducing the costs of production and aggregation of values through the use crop-livestock system (CLS) throughout the year. The CLS is based on the consortium of grain crops, especially corn with tropical forages, mainly of the genus Panicum and Urochloa. The study aimed to evaluate the grain yield of irrigated corn crop intercropped with forage of the genus Panicum and Urochloa. The experiment was c...

  5. Salt preferences of honey bee water foragers.

    Lau, Pierre W; Nieh, James C

    2016-03-15

    The importance of dietary salt may explain why bees are often observed collecting brackish water, a habit that may expose them to harmful xenobiotics. However, the individual salt preferences of water-collecting bees were not known. We measured the proboscis extension reflex (PER) response of Apis mellifera water foragers to 0-10% w/w solutions of Na, Mg and K, ions that provide essential nutrients. We also tested phosphate, which can deter foraging. Bees exhibited significant preferences, with the most PER responses for 1.5-3% Na and 1.5% Mg. However, K and phosphate were largely aversive and elicited PER responses only for the lowest concentrations, suggesting a way to deter bees from visiting contaminated water. We then analyzed the salt content of water sources that bees collected in urban and semi-urban environments. Bees collected water with a wide range of salt concentrations, but most collected water sources had relatively low salt concentrations, with the exception of seawater and swimming pools, which had >0.6% Na. The high levels of PER responsiveness elicited by 1.5-3% Na may explain why bees are willing to collect such salty water. Interestingly, bees exhibited high individual variation in salt preferences: individual identity accounted for 32% of variation in PER responses. Salt specialization may therefore occur in water foragers. PMID:26823100

  6. Foraging ecology of ringed seals (Pusa hispida, beluga whales (Delphinapterus leucas and narwhals (Monodon monoceros in the Canadian High Arctic determined by stomach content and stable isotope analysis

    Jordan K. Matley

    2015-05-01

    Full Text Available Stomach content and stable isotope analysis (δ13C and δ15N from liver and muscle were used to identify habitat and seasonal prey selection by ringed seals (Pusa hispida; n=21, beluga whales (Delphinapterus leucas; n=13 and narwhals (Monodon monoceros; n=3 in the eastern Canadian Arctic. Arctic cod (Boreogadus saida was the main prey item of all three species. Diet reconstruction from otoliths and stable isotope analysis revealed that while ringed seal size influenced prey selection patterns, it was variable. Prey-size selection and on-site observations found that ringed seals foraged on smaller, non-schooling cod whereas belugas and narwhals consumed larger individuals in schools. Further interspecific differences were demonstrated by δ13C and δ15N values and indicated that ringed seals consumed inshore Arctic cod compared to belugas and narwhals, which foraged to a greater extent offshore. This study investigated habitat variability and interseasonal variation in the diet of Arctic marine mammals at a local scale and adds to the sparse data sets available in the Arctic. Overall, these findings further demonstrate the critical importance of Arctic cod to Arctic food webs.

  7. High Titer and Yields Achieved with Novel, Low-Severity Pretreatment Strategy

    2016-03-01

    NREL researchers obtained high concentration sugar syrups in enzymatic hydrolysis that are fermentable to ethanol and other advanced biofuels and intermediate products at high yields. The novel DMR process is simpler and bypasses all severe pretreatment methods, thus reducing the environmental impact. The results are unprecedented. Researchers achieved a high concentration of sugars (230g/L of monomeric sugar and 270 g/L total sugar) and this low toxicity, highly fermentable syrup yielded 86 g/L ethanol (> 90 percent conversion). In addition, the lignin streams from this process can readily be converted to jet or renewable diesel blendstocks through a hydrodeoxygenation step. The NREL-developed, low severity DMR process may potentially replace higher severity chemical pretreatments and associated expensive reactors constructed of exotic alloys with a simpler process, using commercial-scale equipment commonly associated with the pulp and paper industry, to produce high concentration, low toxicity sugar streams and highly reactive lignin streams from non-food renewable biomass for biological and catalytic upgrading to advanced biofuels and chemicals. The simpler DMR process with black liquor recycling could reduce environmental and life-cycle impacts, and repurpose shuttered pulp and paper mills to help revitalize rural economies.

  8. Strategies for achieving a high response rate in a home interview survey

    Power Kevin

    2009-06-01

    Full Text Available Abstract Background Response rates in surveys have been falling over the last 20 years, leading to the need for novel approaches to enhance recruitment. This study describes strategies used to maximise recruitment to a home interview survey of mothers with young children living in areas of high deprivation. Methods Mothers of two year old children received a letter from their GP inviting them to take part in a survey on diet. Participants were subsequently recruited by a researcher. The researcher first tried to contact potential participants by telephone, to discuss the study and make an appointment to conduct a home interview. Where telephone numbers for women could not be obtained from GP records, web searches of publicly available databases were conducted. After obtaining correct telephone numbers, up to six attempts were made to establish contact by telephone. If this was unsuccessful, a postal request for telephone contact was made. Where no telephone contact was achieved, the researcher sent up to two appointments by post to conduct a home interview. Results Participating GPs invited 372 women to take part in a home based interview study. GP practices provided telephone numbers for 162 women, of which 134 were valid numbers. The researcher identified a further 187 numbers from electronic directories. Further searches of GP records by practice staff yielded another 38 telephone numbers. Thus, telephone numbers were obtained for 99% of potential participants. The recruitment rate from telephone contacts was 77%. Most of the gain was achieved within four calls. For the remaining women, contact by post and home visits resulted in 18 further interviews, corresponding to 35% of the women not recruited by telephone. The final interview rate was 82%. This was possible because personal contact was established with 95% of potential participants. Conclusion This study achieved a high response rate in a hard to reach group. This was mainly achieved

  9. Effectiveness of Problem Solving Method In Dynamics And Academic Achievement of High School Students

    Ahmadi, F.; Hamidi, F.; Mohammadzadeh, A.; Ahmadi, M. K. A.

    2010-07-01

    The present research as a per and post tests design with control group investigates the effectiveness of problem solving method as independent variable on academic achievement of students in the second grade of high school in the physics topic of dynamics. The sample consists of four random groups as experimental and control groups which were chosen from the students of the second grade of high school. Each sample consists of 25 participants. The experimental groups were taught in problem solving method without any changing in method for control groups. Data was analyzed using Mixed Analysis Of Variance (MANOVA). Result showed a significant difference between two methods of learning (P<0.05). Further the evaluation of their attitude about problem solving method has been showed that a significant percentage of participants in experimental group were interested to continue that method in other physical topics.

  10. Forage based animal production systems and sustainability, an invited keynote

    Abdul Shakoor Chaudhry

    2008-07-01

    Full Text Available Forages are essential for the successful operation of animal production systems. This is more relevant to ruminants which are heavily dependant upon forages for their health and production in a cost-effective and sustainable manner. While forages are an economical source of nutrients for animal production, they also help conserve the soil integrity, water supply and air quality. Although the role of these forages for animal production could vary depending upon the regional preferences for the animal and forage species, climate and resources, their importance in the success of ruminant production is acknowledged. However with the increasing global human population and urbanisation, the sustainability of forage based animal production systems is sometimes questioned due to the interrelationship between animal production and the environment. It is therefore vital to examine the suitability of these systems for their place in the future to supply quality food which is safe for human consumption and available at a competitive price to the growing human population. Grassland and forage crops are recognised for their contribution to the environment, recreation and efficiency of meat and milk production,. To maintain sustainability, it is crucial that such farming systems remain profitable and environmentally friendly while producing nutritious foods of high economical value. Thus, it is pertinent to improve the nutritive value of grasses and other forage plants in order to enhance animal production to obtain quality food. It is also vital to develop new forages which are efficiently utilised and wasted less by involving efficient animals. A combination of forage legumes, fresh or conserved grasses, crop residues and other feeds could help develop an animal production system which is economically efficient, beneficial and viable. Also, it is crucial to use efficient animals, improved forage conservation methods, better manure handling, and minimum

  11. Evidence for ship noise impacts on humpback whale foraging behaviour.

    Blair, Hannah B; Merchant, Nathan D; Friedlaender, Ari S; Wiley, David N; Parks, Susan E

    2016-08-01

    Noise from shipping activity in North Atlantic coastal waters has been steadily increasing and is an area of growing conservation concern, as it has the potential to disrupt the behaviour of marine organisms. This study examines the impacts of ship noise on bottom foraging humpback whales (Megaptera novaeangliae) in the western North Atlantic. Data were collected from 10 foraging whales using non-invasive archival tags that simultaneously recorded underwater movements and the acoustic environment at the whale. Using mixed models, we assess the effects of ship noise on seven parameters of their feeding behaviours. Independent variables included the presence or absence of ship noise and the received level of ship noise at the whale. We found significant effects on foraging, including slower descent rates and fewer side-roll feeding events per dive with increasing ship noise. During 5 of 18 ship passages, dives without side-rolls were observed. These findings indicate that humpback whales on Stellwagen Bank, an area with chronically elevated levels of shipping traffic, significantly change foraging activity when exposed to high levels of ship noise. This measureable reduction in within-dive foraging effort of individual whales could potentially lead to population-level impacts of shipping noise on baleen whale foraging success. PMID:27512131

  12. Nutritional Characteristics of Forage Grown in South of Benin.

    Musco, Nadia; Koura, Ivan B; Tudisco, Raffaella; Awadjihè, Ghislain; Adjolohoun, Sebastien; Cutrignelli, Monica I; Mollica, Maria Pina; Houinato, Marcel; Infascelli, Federico; Calabrò, Serena

    2016-01-01

    In order to provide recommendations on the most useful forage species to smallholder farmers, eleven grass and eleven legume forages grown in Abomey-Calavi in Republic of Benin were investigated for nutritive value (i.e. chemical composition and energy content) and fermentation characteristics (i.e. gas and volatile fatty acid production, organic matter degradability). The in vitro gas production technique was used, incubating the forages for 120 h under anaerobic condition with buffalo rumen fluid. Compared to legume, tropical grass forages showed lower energy (8.07 vs 10.57 MJ/kg dry matter [DM]) and crude protein level (16.10% vs 19.91% DM) and higher cell wall content (neutral detergent fiber: 63.8% vs 40.45% DM), respectively. In grass forages, the chemical composition showed a quite high crude protein content; the in vitro degradability was slightly lower than the range of tropical pasture. The woody legumes were richer in protein and energy and lower in structural carbohydrates than herbaceous plants, however, their in vitro results are influenced by the presence of complex compounds (i.e. tannins). Significant correlations were found between chemical composition and in vitro fermentation characteristics. The in vitro gas production method appears to be a suitable technique for the evaluation of the nutritive value of forages in developing countries. PMID:26732328

  13. Is Early Ability Grouping Good for High-Achieving Students' Psychosocial Development? Effects of the Transition into Academically Selective Schools

    Becker, Michael; Neumann, Marko; Tetzner, Julia; Böse, Susanne; Knoppick, Henrike; Maaz, Kai; Baumert, Jürgen; Lehmann, Rainer

    2014-01-01

    The present study investigates school context effects on psychosocial characteristics (academic self-concept, peer relations, school satisfaction, and school anxiety) of high-achieving and gifted students. Students who did or did not make an early transition from elementary to secondary schools for high-achieving and gifted students in 5th grade…

  14. Trajectories of Chinese Students' Sense of School Belonging and Academic Achievement over the High School Transition Period

    Liu, Yangyang; Lu, Zuhong

    2011-01-01

    The present study identified the different patterns of Chinese students' academic achievement trajectories over the high school transition period and examined the relationships between students' sense of school belonging trajectories and the different patterns of academic achievement trajectories. In a sample of 567 Chinese high school students, a…

  15. A Comparison of Strategic Development for Multiplication Problem Solving in Low-, Average-, and High-Achieving Students

    Zhang, Dake; Ding, Yi; Barrett, Dave E.; Xin, Yan Ping; Liu, Ru-de

    2014-01-01

    The present study investigated the differences of strategy use between low-, average-, and high-achieving students when solving different multiplication problems. Nineteen high-, 48 average-, and 17 low-achieving students participated in this study. All participants were asked to complete three different multiplication tests and to explain how…

  16. Self-Concept and Academic Achievement: Investigating Their Importance as Discriminators of Academic Track Membership in High School.

    Byrne, Barbara M.

    1990-01-01

    Using linear discriminant analysis, two samples of Canadian high school students (n=929 and n=968) were tested using measures of self-concept, academic self-concept, and academic achievement. Academic self-concept was more effective than was academic achievement in differentiating between low-track and high-track students. (SLD)

  17. Science literacy in high school students: A comparison of achievement in two curriculum approaches

    McAlister, Diane C.

    2009-12-01

    Academic achievement as measured by the Florida Comprehensive Assessment Test (FCAT) in science for 367 students in two science curriculum options, integrated science and the traditional subject-specific courses, in one central Florida high school were compared. A multivariate analysis of covariance (MANCOVA) of science curriculum choice was analyzed for three variables, total FCAT score, earth science subscore, and scientific thinking subscore. Covariate of academic ability as defined by grade point average (GPA) and academic focus as defined by post secondary plans were considered for use. Analysis of statistically significant results was completed through analysis of covariance (ANCOVA). While statistically significant results were found in favor of the traditional curriculum group, additional statistical analysis of the curriculum groups for differences in socioeconomic status (SES), gender, and instructional level led to a logistic regression to explore the ability of these variables, GPA, and total FCAT score to predict curriculum group membership. GPA, level of instruction and FCAT score were found to be statistically significant predictors. Final conclusions to the study indicated a significant difference in scientific literacy for the two groups in favor of the traditional curriculum. However, logistic regression results indicated that due to significant differences in SES, gender, GPA, and level of instruction for the groups, the differences in academic achievement were probably due to factors other than curriculum design. Limitations of the study and suggestions for further research were presented.

  18. A Quantitative Literature Review of Cooperative Learning Effects on High School and College Chemistry Achievement

    Bowen, Craig W.

    2000-01-01

    This paper has two purposes. First, the reader is given an overview on how quantitative literature reviews (meta-analyses) can be conducted to give overall estimates of the quantitative impact an instructional treatment has on a specific student outcome. The second purpose is to illustrate how such a literature review is carried out by examining studies on using cooperative learning to teach chemistry at the high school and college levels. This analysis extends earlier reported work on effects of cooperative learning on achievement in college-level science, mathematics, and engineering and technology (SMET) courses. The analysis shows that while median student performance in a traditional course is at the 50th percentile, the median student performance in a cooperative learning environment is 14 percentile points higher.

  19. Do crabeater seals forage cooperatively?

    Gales, Nicholas J.; Fraser, William R.; Costa, Daniel P.; Southwell, Colin

    2004-08-01

    Crabeater seals are abundant pack-ice predators that feed almost exclusively on krill. They have a circumpolar distribution and are generally sighted hauled out on ice floes alone or in pairs. Here we report our observations of a sighting of 150-200 crabeater seals, which were synchronised in their diving and surfacing behaviour, along with a summary of similar observations from western Antarctica of large groups of crabeater seals in synchronous dive cycles. We report on the low frequency of sightings of such groups during Antarctic pack-ice seal surveys in eastern (Greater) Antarctica. We examine plausible hypotheses to explain these observations, and suggest this behaviour is likely to represent some form of cooperative foraging behaviour, whereby a net advantage in individual energy intake rates is conferred to each seal. Current research on crabeater seal foraging using satellite-linked dive recorders is unlikely to provide sufficiently fine-scale data to examine this hypothesis. Nor will this approach indicate if a seal is foraging with conspecifics. The use of remote or animal-borne camera systems is more likely to provide an insight into fine-scale foraging tactics, as well as the possible, occasional use of cooperative foraging strategies.

  20. Held Back: The Impact of Curricular and Pedagogical Factors on Tested Achievement in High School Mathematics

    Agvanian, Zara

    2013-01-01

    This study examined the impact of curricular factors and teaching practices on students' tested achievement in mathematics, explored the best predictors of the tested achievement, and examined differences in the tested achievement among student subgroups. The study utilized qualitative and quantitative methods and triangulated findings from…

  1. Examining the Long-Term Impact of Achievement Loss during the Transition to High School

    Smith, Joshua S.

    2006-01-01

    Research shows that prior academic achievement is a strong predictor of future academic performance. For some students, the transition from one educational environment to another is associated with academic challenges and achievement loss. This study examined the extent to which achievement loss during the transition from middle school to high…

  2. Development of a 14-inch ID High-Pressure Hybrid Riser for SBOP Drilling Développement d’un riser hybride 14”ID haute pression pour le forage SBOP

    Persent E.

    2009-11-01

    Full Text Available This paper discusses the development of a 14-inch ID high-pressure hybrid riser (10 000 psi for surface BOP drilling in ultra-deep water (10 000 ft. The high-pressure hybrid riser system is obtained by adapting and combining two existing technologies, previously developed by the IFP for other applications: – the Clip connector, a double breech-block type connector to provide a quick and safe connection for riser joints; – hybrid pipe technology, a steel pipe hoop-wound with tapes of carbon fibers impregnated with polyamide thermoplastic resin. IFP has developed a new 14-inch ID HP Clip connector for the hybrid riser application. The connector is capable of withstanding a 2.8 million pound tension and a 10 000 psi operating pressure. In addition, a 16-inch nominal OD hybrid riser pipe has been designed to replace the steel riser pipe with a thinnerwalled hoop-wound steel pipe. The significant weight savings that can be achieved with the hybrid riser pipe make it possible to design an effective riser architecture to withstand the high pressure and deep water requirements. Pursuant to design studies, a 14-inch ID prototype assembly consisting of two hybrid riser pipe sections with a high-pressure Clip connector was manufactured. A test program, including burst and collapse tests as well as cyclic fatigue testing, was formulated and carried out to qualify the performance of the Clip connector and hybrid riser pipe system. Completion of hybrid pipe additional fatigue testing and realization of a scale-one field testing of the hybrid riser are considered as the next steps of the project. To date, the main test results (burst, collapse, fatigue resistance confirm that the Clip connector and the hybrid pipe technologies are well suited for ultra-deep sea drilling with a surface BOP. However, the fatigue resistance of hybrid riser pipes still needs to be better characterized. Cet article présente le développement d’un riser hybride 14”ID haute

  3. Combination of Engineering Physics and Modern Scientific Management in High Technology Achievements

    Arezu Jahanshir

    2015-02-01

    Full Text Available Studying and contemplating the current managerial structure of developed countries show that management and its strategic results have lost their own traditional and usual concept. In these countries, modern management has been developed depending on the knowledge-based infrastructures. In other words, long-term and short-term modern management in all fields is founded upon the predetermined ordered scientific principles and structures that has entered different scientific concepts, wishes and objectives into this field and affects both  and non-organizational managerial procedure observed widely in each field of sciences. For this reason, the results and achievements of knowledge-based management of developed countries indicate the significant development of a kind of modern management in the basic and human sciences. While it is doubtlessly true that developed countries are better endowed more than others to compete in the global knowledge high technologies and new equipment management, the problem is rarely that the fewer successful countries lack sufficient scientific high technologies management.

  4. Highly efficient industrial large-area black silicon solar cells achieved by surface nanostructured modification

    Li, Ping; Wei, Yi; Zhao, Zengchao; Tan, Xin; Bian, Jiming; Wang, Yuxuan; Lu, Chunxi; Liu, Aimin

    2015-12-01

    Traditional black silicon solar cells show relatively low efficiencies due to the high surface recombination occurring at the front surfaces. In this paper, we present a surface modification process to suppress surface recombination and fabricate highly efficient industrial black silicon solar cells. The Ag-nanoparticle-assisted etching is applied to realize front surface nanostructures on silicon wafers in order to reduce the surface reflectance. Through a further tetramethylammonium hydroxide (TMAH) treatment, the carrier recombination at and near the surface is greatly suppressed, due to a lower surface dopant concentration after the surface modification. This modified surface presents a low reflectivity in a range of 350-1100 nm. Large-area solar cells with an average conversion efficiency of 19.03% are achieved by using the TMAH treatment of 30 s. This efficiency is 0.18% higher than that of standard silicon solar cells with pyramidal surfaces, and also a remarkable improvement compared with black silicon solar cells without TMAH modifications.

  5. Important aspects for consideration in minimizing plant outage times. Swiss experience in achieving high availability

    Operation of Swiss nuclear power plants has not been entirely free of trouble. They have experienced defective fuel elements, steam generator tube damage, excessive vibration of the core components, leakages in the recirculation pump seals and excessive corrosion and erosion in the steam-feedwater plant. Despite these technical problems in the early life of the plants, on overall balance the plants can be considered to have performed exceedingly well. The safety records from more than 40 reactor-years of operation are excellent and, individually and collectively, the capacity factors obtained are among the highest in the world. The problems mentioned have been solved and the plants continue operation with high availabilities. This success can be attributed to the good practices of the utilities with regard to the choice of special design criteria, plant organization, plant operation and plant maintenance, and also to the pragmatic approach of the licensing authorities and their consultants to quality assurance and quality control. The early technical problems encountered, the corresponding solutions adopted and the factors that contributed towards achieving high availabilities in Swiss nuclear power plants are briefly described. (author)

  6. Are seabirds foraging for unpredictable resources?

    Weimerskirch, Henri

    2007-02-01

    It is generally assumed that the extreme life history traits of pelagic seabirds, such as low fecundity or slow growth of chicks, result from the difficulties obtaining energy at sea from unpredictable and patchily distributed resources. However, little information on seabird prey distribution and availability exists to sustain this widely accepted hypothesis. Using tracking studies of 68 sub-populations of flying seabirds, I examine whether it is possible to gain information on the predictability of their marine resources. Because prey are clustered from fine to large scale in nested unities, from swarms to patches and concentrations of patches, it is important to take into account spatial scale. In temperate and polar regions, at large and meso-scales, seabirds appear to have a good knowledge of the location and concentrations of patches and generally use a commuting type of trip to reach foraging zones. Predictability appears to be high at large and meso-scales, with individuals from each sub-population heading in a particular direction from the colony to reach favoured habitats of known enhanced productivity such as shelf edges, frontal zones, upwellings. Within these mesoscale features, the animals use an area-restricted search behaviour to search for patches and swarms at finer scales. Using information on foraging site fidelity of individual birds, I show that differences in predictability at coarse scales are related to the distance and time spent foraging, and in particular to the specific types of foraging habitat. Some habitats appear to be more predictable than others: birds return consistently to the same coarse-scale sectors on shelf edges, whereas predictability is low in oceanic waters, even in frontal zones. Preliminary results on tropical species suggest that the environment here is less predictable in tropic than in temperate or polar zones. This review highlights that patchiness and predictability of marine resources are complex notions

  7. Effects of Intercropping forage Legumes and Maize Grain and Forage Yield in the Upper Midland Zone 1 and 4 (UM1 and 4) of Kenya

    Intercropping forage legumes and cereal crops could assist smallholder farmers to increase the quantity and quality of livestock feeds per unit land particularly during dry season. Two studies were carried out in the upper midland zone (UM1) at Kisii (UM4) at Kitale to asses the effects of intercropping forage legumes and maize on maize grain yield and quantity of livestock feeds. In the first study, five annual/biannual legumes comprising of three- grain type and two herbaceous forage legumes were intercropped with maize at Kisii and Kitale. The second study involved three perennial forage legumes. Results of two cropping seasons at Kitale and three seasons in Kisii are reported.. Intercropping of grain type legume with maize had no significant effects on maize grain yield and stover DM yield at both sites.However, the herbaceous forage legumes (Dolichos lablab cv. Rongai and Macuma pururiens) significantly reduced maize grain yield compared to maize top dressed with 60 kg N ha-1 although maize stover and legume DM yields were not significantly affected. Total forage yields (maize stover + legume herbage) were significantly increased in forage legume intercrops (P -1. The results demonstrate that increased quantity and quality of dairy cattle feed may be achieved by intercropping forage legumes and maize although it may cause some reduction in maize yield. Practical implications of this technology in terms of economic evaluation are discussed significantly reduced maize grain yield. Decreases in maize green yield were associated with legume herbage yields above 3 t ha-1. The results demonstrate that increased quantity and quality of dairy cattle feed may be achieved by intercropping forage legumes and maize although it may cause reduction in maize yield. Practical implications of this technology in terms of economic evaluation are discussed

  8. Intellectual and non-intellectual determinants of high academic achievement – the contribution of personality traits to the assessment of high performance potential

    Silvia Schubhart; Stefana Holocher-Ertl; Georg Wilflinger

    2013-01-01

    In this paper a study is presented which tries to explain and predict high academic achievement in children or adolescents on the basis of intellectual and non-intellectual determinants – in this case, performance relevant personality traits as well as the social environment of stimulation. The prognosis of high academic achievement is based on a new diagnostic model, the Viennese Diagnostic Model of High Achievement Potential, which undergoes its first empirical validation here. The resu...

  9. Foraging in corallivorous butterflyfish varies with wave exposure

    Noble, Mae M.; Pratchett, Morgan S.; Coker, Darren J.; Cvitanovic, Christopher; Fulton, Christopher J.

    2014-06-01

    Understanding the foraging patterns of reef fishes is crucial for determining patterns of resource use and the sensitivity of species to environmental change. While changes in prey availability and interspecific competition have been linked to patterns of prey selection, body condition, and survival in coral reef fishes, rarely has the influence of abiotic environmental conditions on foraging been considered. We used underwater digital video to explore how prey availability and wave exposure influence the behavioural time budgets and prey selectivity of four species of obligate coral-feeding butterflyfishes. All four species displayed high selectivity towards live hard corals, both in terms of time invested and frequency of searching and feeding events. However, our novel analysis revealed that such selectivity was sensitive to wave exposure in some species, despite there being no significant differences in the availability of each prey category across exposures. In most cases, these obligate corallivores increased their selectivity towards their most favoured prey types at sites of high wave exposure. This suggests there are costs to foraging under different wave environments that can shape the foraging patterns of butterflyfishes in concert with other conditions such as prey availability, interspecific competition, and territoriality. Given that energy acquisition is crucial to the survival and fitness of fishes, we highlight how such environmental forcing of foraging behaviour may influence the ecological response of species to the ubiquitous and highly variable wave climates of shallow coral reefs.

  10. Qualitative research study of high-achieving females' life experiences impacting success

    Butcher, Ann Patrice

    2003-07-01

    This qualitative study investigated the life experiences of five academically gifted female students in math and science in reflection of their elementary learning prior to enrollment at a prestigious science and mathematics high school. The elite high school limits admission to the state of Illinois' top students. The purpose of this study is to unfold the story of five academically gifted females in attendance at the elite high school reflecting on their life experiences in elementary school that contributed to their current academic success. Twelve female students, who at the time of this study were currently in their senior year (12th grade) of high school, were solicited from the top academic groups who are regarded by their teachers as highly successful in class. Students were selected as part of the study based on academic status, survey completion and interest in study, Caucasian and Asian ethnicity, locale of elementary school with preference given to the variety of school demographics---urban, suburban, and rural---further defined the group to the core group of five. All female participants were personally interviewed and communicated via Internet with the researcher. Parents and teachers completing surveys as well met the methodological requirements of triangulation. An emergent theme of paternal influence came from the research. Implications supported in the research drawn from this study to increase achievement of academically gifted females include: (a) proper early identification of learner strengths plays a role; (b) learning with appropriate intellectual peers is more important than learning with their age group; (c) teachers are the greatest force for excellent instruction; (d) effective teaching strategies include cooperative learning, multi-sensory learning, problem-based learning, and hands-on science; (e) rigor in math is important; (f) gender and stereotypes need not be barriers; (g) outside interests and activities are important for self

  11. Intellectual and non-intellectual determinants of high academic achievement – the contribution of personality traits to the assessment of high performance potential

    Silvia Schubhart

    2013-09-01

    Full Text Available In this paper a study is presented which tries to explain and predict high academic achievement in children or adolescents on the basis of intellectual and non-intellectual determinants – in this case, performance relevant personality traits as well as the social environment of stimulation. The prognosis of high academic achievement is based on a new diagnostic model, the Viennese Diagnostic Model of High Achievement Potential, which undergoes its first empirical validation here. The results show impressive evidence that performance-relevant personality traits and categories of social environment of stimulation contribute to high academic achievement in children and adolescents of above-average intelligence.

  12. Optimal microelectromechanical systems (MEMS) device for achieving high pyroelectric response of AlN

    Kebede, Bemnnet; Coutu, Ronald A.; Starman, LaVern

    2014-03-01

    This paper discusses research being conducted on aluminum nitride (AlN) as a pyroelectric material for use in detecting applications. AlN is being investigated because of its high pyroelectric coefficient, thermal stability, and high Curie temperature. In order to determine suitability of the pyroelectric properties of AlN for use as a detector, testing of several devices was conducted. These devices were fabricated using microelectromechanical systems (MEMS) fabrication processes; the devices were also designed to allow for voltage and current measurements. The deposited AlN films used were 150 nm - 300 nm in thickness. Thin-films were used to rapidly increase the temperature response after the thermal stimulus was applied to the pyroelectric material. This is important because the pyroelectric effect is directly proportional to the rate of temperature change. The design used was a face-electrode bridge that provides thermal isolation which minimizes heat loss to the substrate, thereby increasing operation frequency of the pyroelectric device. A thermal stimulus was applied to the pyroelectric material and the response was measured across the electrodes. A thermal imaging camera was used to monitor the changes in temperature. Throughout the testing process, the annealing temperatures, type of layers, and thicknesses were also varied. These changes resulted in improved MEMS designs, which were fabricated to obtain an optimal design configuration for achieving a high pyroelectric response. A pyroelectric voltage response of 38.9 mVp-p was measured without filtering, 12.45 mVp-p was measured in the infrared (IR) region using a Si filter, and 6.38 mVp-p was measured in the short wavelength IR region using a long pass filter. The results showed that AlN's pyroelectric properties can be used in detecting applications.

  13. Relationships between high-stakes testing policies and student achievement after controlling for demographic factors in aggregated data.

    Gregory J. Marchant

    2006-11-01

    Full Text Available With the mandate of No Child Left Behind, high-stakes achievement testing is firmly in place in every state. The few studies that have explored the effectiveness of high-stakes testing using NAEP scores have yielded mixed results. This study considered state demographic characteristics for each NAEP testing period in reading, writing, mathematics, and science from 1992 through 2002, in an effort to examine the relation of high-stakes testing policies to achievement and changes in achievement between testing periods. As expected, demographic characteristics and their changes were related significantly to most achievement outcomes, but high-stakes testing policies demonstrated few relationships with achievement. The few relationships between high-stakes testing and achievement or improvement in reading, writing, or science tended to appear only when demographic data were missing; and the minimal relationships with math achievement were consistent with findings in previous research. Considering the cost and potential unintended negative consequences, high-stakes testing policies seem to provide a questionable means of improving student learning.

  14. Forage characteristics affecting meat goat preferences for forage chicory cultivars

    Concentration of bitter sesquiterpene lactones (SL), lactucin, lactucopicrin, and 8-deoxylactucin, has been associated with low soil phosphorus fertility and reduced livestock preference for forage chicory (Cichorium intybus L.). We evaluated the effect of cultivar and available soil P (ASP) on mea...

  15. American High School Students from Different Ethnic Backgrounds: The Role of Parents and the Classroom in Achievement Motivation

    Kim, Jung-In

    2015-01-01

    The purpose of this study was to investigate the relationships between ethnically diverse US high school students' (N = 331) perceptions of their parents' or classroom's motivating factors and their achievement motivation in their math class, connecting achievement goal orientation and self-determination theories. Two hypothesized path models were…

  16. Teacher Credentials and Student Achievement in High School: A Cross-Subject Analysis with Student Fixed Effects

    Clotfelter, Charles T.; Ladd, Helen F.; Vigdor, Jacob L.

    2010-01-01

    We use data on statewide end-of-course tests in North Carolina to examine the relationship between teacher credentials and student achievement at the high school level. We find compelling evidence that teacher credentials, particularly licensure and certification, affects student achievement in systematic ways and that the magnitudes are large…

  17. Validation of a Test to Measure Need-Achievement Motivation Among American Indian High School Students. Final Report.

    Michener, Bryan P.

    A cross-cultural test measuring need-achievement motivation was developed and administered to 634 American Indian, Spanish American and Anglo high school seniors attending 24 schools, including Federal, public and private boarding and day types. Need-achievement was related to the following types of measures: academic, aptitude, intelligence, and…

  18. The Impact of Principal Perception on Student Academic Climate and Achievement in High School: How Does It Measure Up?

    Urick, Angela; Bowers, Alex J.

    2014-01-01

    The purpose of this study is to examine the independent direct effects of student and principal perceptions of academic climate on student achievement in high school. To date, few studies have considered the influence of principal perceptions of academic climate on student achievement. In the present study, we test a set of two-level hierarchical…

  19. Extrinsic Motivation for Large-Scale Assessments: A Case Study of a Student Achievement Program at One Urban High School

    Emmett, Joshua; McGee, Dean

    2013-01-01

    The purpose of this case study was to discover the critical attributes of a student achievement program, known as "Think Gold," implemented at one urban comprehensive high school as part of the improvement process. Student achievement on state assessments improved during the period under study. The study draws upon perspectives on motivation as a…

  20. Multiple-stage decisions in a marine central-place forager.

    Friedlaender, Ari S; Johnston, David W; Tyson, Reny B; Kaltenberg, Amanda; Goldbogen, Jeremy A; Stimpert, Alison K; Curtice, Corrie; Hazen, Elliott L; Halpin, Patrick N; Read, Andrew J; Nowacek, Douglas P

    2016-05-01

    Air-breathing marine animals face a complex set of physical challenges associated with diving that affect the decisions of how to optimize feeding. Baleen whales (Mysticeti) have evolved bulk-filter feeding mechanisms to efficiently feed on dense prey patches. Baleen whales are central place foragers where oxygen at the surface represents the central place and depth acts as the distance to prey. Although hypothesized that baleen whales will target the densest prey patches anywhere in the water column, how depth and density interact to influence foraging behaviour is poorly understood. We used multi-sensor archival tags and active acoustics to quantify Antarctic humpback whale foraging behaviour relative to prey. Our analyses reveal multi-stage foraging decisions driven by both krill depth and density. During daylight hours when whales did not feed, krill were found in deep high-density patches. As krill migrated vertically into larger and less dense patches near the surface, whales began to forage. During foraging bouts, we found that feeding rates (number of feeding lunges per hour) were greatest when prey was shallowest, and feeding rates decreased with increasing dive depth. This strategy is consistent with previous models of how air-breathing diving animals optimize foraging efficiency. Thus, humpback whales forage mainly when prey is more broadly distributed and shallower, presumably to minimize diving and searching costs and to increase feeding rates overall and thus foraging efficiency. Using direct measurements of feeding behaviour from animal-borne tags and prey availability from echosounders, our study demonstrates a multi-stage foraging process in a central place forager that we suggest acts to optimize overall efficiency by maximizing net energy gain over time. These data reveal a previously unrecognized level of complexity in predator-prey interactions and underscores the need to simultaneously measure prey distribution in marine central place forager

  1. Food limitation of sea lion pups and the decline of forage off central and southern California.

    McClatchie, Sam; Field, John; Thompson, Andrew R; Gerrodette, Tim; Lowry, Mark; Fiedler, Paul C; Watson, William; Nieto, Karen M; Vetter, Russell D

    2016-03-01

    California sea lions increased from approximately 50 000 to 340 000 animals in the last 40 years, and their pups are starving and stranding on beaches in southern California, raising questions about the adequacy of their food supply. We investigated whether the declining sea lion pup weight at San Miguel rookery was associated with changes in abundance and quality of sardine, anchovy, rockfish and market squid forage. In the last decade off central California, where breeding female sea lions from San Miguel rookery feed, sardine and anchovy greatly decreased in biomass, whereas market squid and rockfish abundance increased. Pup weights fell as forage food quality declined associated with changes in the relative abundances of forage species. A model explained 67% of the variance in pup weights using forage from central and southern California and 81% of the variance in pup weights using forage from the female sea lion foraging range. A shift from high to poor quality forage for breeding females results in food limitation of the pups, ultimately flooding animal rescue centres with starving sea lion pups. Our study is unusual in using a long-term, fishery-independent dataset to directly address an important consequence of forage decline on the productivity of a large marine predator. Whether forage declines are environmentally driven, are due to a combination of environmental drivers and fishing removals, or are due to density-dependent interactions between forage and sea lions is uncertain. However, declining forage abundance and quality was coherent over a large area (32.5-38° N) for a decade, suggesting that trends in forage are environmentally driven. PMID:27069651

  2. Marine foraging ecology influences mercury bioaccumulation in deep-diving northern elephant seals

    Peterson, Sarah H.; Ackerman, Joshua T.; Costa, Daniel P.

    2015-01-01

    Mercury contamination of oceans is prevalent worldwide and methylmercury concentrations in the mesopelagic zone (200–1000 m) are increasing more rapidly than in surface waters. Yet mercury bioaccumulation in mesopelagic predators has been understudied. Northern elephant seals (Mirounga angustirostris) biannually travel thousands of kilometres to forage within coastal and open-ocean regions of the northeast Pacific Ocean. We coupled satellite telemetry, diving behaviour and stable isotopes (carbon and nitrogen) from 77 adult females, and showed that variability among individuals in foraging location, diving depth and δ13C values were correlated with mercury concentrations in blood and muscle. We identified three clusters of foraging strategies, and these resulted in substantially different mercury concentrations: (i) deeper-diving and offshore-foraging seals had the greatest mercury concentrations, (ii) shallower-diving and offshore-foraging seals had intermediate levels, and (iii) coastal and more northerly foraging seals had the lowest mercury concentrations. Additionally, mercury concentrations were lower at the end of the seven-month-long foraging trip (n = 31) than after the two-month- long post-breeding trip (n = 46). Our results indicate that foraging behaviour influences mercury exposure and mesopelagic predators foraging in the northeast Pacific Ocean may be at high risk for mercury bioaccumulation.

  3. A comparison of rural high school students in Germany with rural Tennessee high school students' mathematics and science achievement

    Harding, R. Fredrick

    This descriptive study compared the science and mathematics aptitudes and achievement test scores for the final school year students in rural White County and Van Buren County, Tennessee with rural county students in Germany. In accordance with the previous research literature (Stevenson, 2002), German students outperformed U.S. students on The International Trends in Math and Science test (TIMSS). As reform in the U.S. education system has been underway, this study intended to compare German county student final school year performance with White County and Van Buren County (Grade 12) performance in science and mathematics. The entire populations of 176 White and Van Buren Counties senior high final school year students were compared with 120 school final year students from two rural German county high schools. The student responses to identical test and questionnaire items were compared using the t-test statistical analysis. In conclusion after t-test analyses, there was no significant difference (p>.05 level) in student attitudes on the 27 problem achievement and the 35 TIMSS questionnaire items between the sampled population of 120 German students compared with the population of 176 White and Van Buren students. Also, there was no statistically significant difference (p>.05 level) between the German, White, and Van Buren County rural science and math achievement in the TIMSS problem section of the final year test. Based on the research, recommendations to improve U.S. student scores to number one in the world include making changes in teaching methodology in mathematics and science; incorporating pamphlet lessons rather than heavily reliance on textbooks; focusing on problem solving; establishing an online clearinghouse for effective lessons; creating national standards in mathematics and science; matching students' course choices to job aspirations; tracking misbehaving students rather than mainstreaming them into the regular classroom; and designing

  4. Achieving High Aspect Ratio of Track Length to Width in Molds for Discrete Track Recording Media

    S. N. Piramanayagam

    2008-06-01

    Full Text Available Discrete track media (DTM fabricated by nanoimprint lithography (NIL is considered as a potential technology for future hard disk drives (HDD. In the fabrication of a master mold for NIL, patterning the resist tracks with a narrow distribution in the width is the first critical step. This paper reports the challenges involved in the fabrication of high aspect ratio discrete tracks on Polymethylmethacrylate (PMMA resist by means of electron beam lithography. It was observed that fabrication parameters applied for successful patterning of discrete tracks in nanoscale length were not directly suitable for the patterning of discrete tracks in micron scale. Hence different approaches such as thick layer resist coating, introducing of post exposure baking process, and varying of exposure parameters were used in order to achieve uniform sharp discrete tracks in micron scale length on the resist. The optimal parameters were used to pattern 20 μm long tracks with 70 nm track pitch on the resist.

  5. The Stories Clinicians Tell: Achieving High Reliability and Improving Patient Safety.

    Cohen, Daniel L; Stewart, Kevin O

    2016-01-01

    The patient safety movement has been deeply affected by the stories patients have shared that have identified numerous opportunities for improvements in safety. These stories have identified system and/or human inefficiencies or dysfunctions, possibly even failures, often resulting in patient harm. Although patients' stories tell us much, less commonly heard are the stories of clinicians and how their personal observations regarding the environments they work in and the circumstances and pressures under which they work may degrade patient safety and lead to harm.If the health care industry is to function like a high-reliability industry, to improve its processes and achieve the outcomes that patients rightly deserve, then leaders and managers must seek and value input from those on the front lines-both clinicians and patients. Stories from clinicians provided in this article address themes that include incident identification, disclosure and transparency, just culture, the impact of clinical workload pressures, human factors liabilities, clinicians as secondary victims, the impact of disruptive and punitive behaviors, factors affecting professional morale, and personal failings. PMID:26580146

  6. Effect of bead and illustrations models on high school students' achievement in molecular genetics

    Rotbain, Yosi; Marbach-Ad, Gili; Stavy, Ruth

    2006-05-01

    Our main goal in this study was to explore whether the use of models in molecular genetics instruction in high school can contribute to students' understanding of concepts and processes in genetics. Three comparable groups of 11th and 12th graders participated: The control group (116 students) was taught in the traditional lecture format, while the others received instructions which integrated a bead model (71 students), or an illustration model (71 students). Similar instructions and the same guiding questions accompanied the two models. We used three instruments: a multiple-choice and an open-ended written questionnaire, as well as personal interviews. Five of the multiple-choice questions were also given to students before receiving their genetics instruction (pretest). We found that students who used one of the two types of models improved their knowledge in molecular genetics compared to the control group. However, the open-ended questions revealed that bead model activity was significantly more effective than illustration activity. On the basis of these findings we conclude that, though it is advisable to use a three-dimensional model, such as the bead model, engaging students in activities with illustrations can still improve their achievement in comparison to traditional instruction.

  7. New Powder Metallurgical Approach to Achieve High Fatigue Strength in Ti-6Al-4V Alloy

    Cao, Fei; Ravi Chandran, K. S.; Kumar, Pankaj; Sun, Pei; Zak Fang, Z.; Koopman, Mark

    2016-05-01

    Recently, manufacturing of titanium by sintering and dehydrogenation of hydride powders has generated a great deal of interest. An overarching concern regarding powder metallurgy (PM) titanium is that critical mechanical properties, especially the high-cycle fatigue strength, are lower than those of wrought titanium alloys. It is demonstrated here that PM Ti-6Al-4V alloy with mechanical properties comparable (in fatigue strength) and exceeding (in tensile properties) those of wrought Ti-6Al-4V can be produced from titanium hydride powder, through the hydrogen sintering and phase transformation process. Tensile and fatigue behavior, as well as fatigue fracture mechanisms, have been investigated under three processing conditions. It is shown that a reduction in the size of extreme-sized pores by changing the hydride particle size distribution can lead to improved fatigue strength. Further densification by pneumatic isostatic forging leads to a fatigue strength of ~550 MPa, comparable to the best of PM Ti-6Al-4V alloys prepared by other methods and approaching the fatigue strengths of wrought Ti-6Al-4V alloys. The microstructural factors that limit fatigue strength in PM titanium have been investigated, and pathways to achieve greater fatigue strengths in PM Ti-6Al-4V alloys have been identified.

  8. Safety management systems and their role in achieving high standards of operational safety

    Achieving high standards of operational safety requires a robust management framework that is visible to all personnel with responsibility for its implementation. The structure of the management framework must ensure that all processes used to manage safety interlink in a logical and coherent manner, that is, they form a management system that leads to continuous improvement in safety performance. This Paper describes BNFL's safety management system (SMS). The SMS has management processes grouped within 5 main elements: 1. Policy, 2. Organisation, 3. Planning and Implementation, 4. Measuring and Reviewing Performance, 5. Audit. These elements reflect the overall process of setting safety objective (from Policy), measuring success and reviewing the performance. Effective implementation of the SMS requires senior managers to demonstrate leadership through their commitment and accountability. However, the SMS as a whole reflects that every employee at every level within BNFL is responsible for safety of operations under their control. The SMS therefore promotes a proactive safety culture and safe operations. The system is formally documented in the Company's Environmental, Health and Safety (EHS) Manual. Within in BNFL Group, the Company structures enables the Manual to provide overall SMS guidance and co-ordination to its range of nuclear businesses. Each business develops the SMS to be appropriate at all levels of its organisation, but ensuring that each level is consistent with the higher level. The Paper concludes with a summary of BNFL's safety performance. (author)

  9. Comparative digestibility by cattle versus sheep: effect of forage quality.

    Soto-Navarro, S A; Lopez, R; Sankey, C; Capitan, B M; Holland, B P; Balstad, L A; Krehbiel, C R

    2014-04-01

    after feeding. Ruminal VFA were generally not influenced (P ≥ 0.06) by ruminant specie. Results suggest that apparent total tract digestibilities are more similar among ruminant species when moderate- to high-quality forages are evaluated. However, sheep are not an adequate model for cattle when low-quality forages are compared because cattle digest low-quality forages to a greater extent than sheep. Expressing digestibility as digestible intake per unit of BW allows for a wider range of forage qualities to be compared when substituting sheep for cattle. PMID:24663196

  10. Achieving accurate simulations of urban impacts on ozone at high resolution

    The effects of urbanization on ozone levels have been widely investigated over cities primarily located in temperate and/or humid regions. In this study, nested WRF-Chem simulations with a finest grid resolution of 1 km are conducted to investigate ozone concentrations [O3] due to urbanization within cities in arid/semi-arid environments. First, a method based on a shape preserving Monotonic Cubic Interpolation (MCI) is developed and used to downscale anthropogenic emissions from the 4 km resolution 2005 National Emissions Inventory (NEI05) to the finest model resolution of 1 km. Using the rapidly expanding Phoenix metropolitan region as the area of focus, we demonstrate the proposed MCI method achieves ozone simulation results with appreciably improved correspondence to observations relative to the default interpolation method of the WRF-Chem system. Next, two additional sets of experiments are conducted, with the recommended MCI approach, to examine impacts of urbanization on ozone production: (1) the urban land cover is included (i.e., urbanization experiments) and, (2) the urban land cover is replaced with the region’s native shrubland. Impacts due to the presence of the built environment on [O3] are highly heterogeneous across the metropolitan area. Increased near surface [O3] due to urbanization of 10–20 ppb is predominantly a nighttime phenomenon while simulated impacts during daytime are negligible. Urbanization narrows the daily [O3] range (by virtue of increasing nighttime minima), an impact largely due to the region’s urban heat island. Our results demonstrate the importance of the MCI method for accurate representation of the diurnal profile of ozone, and highlight its utility for high-resolution air quality simulations for urban areas. (letter)

  11. Achieving numerical accuracy and high performance using recursive tile LU factorization with partial pivoting

    Dongarra, Jack

    2013-09-18

    The LU factorization is an important numerical algorithm for solving systems of linear equations in science and engineering and is a characteristic of many dense linear algebra computations. For example, it has become the de facto numerical algorithm implemented within the LINPACK benchmark to rank the most powerful supercomputers in the world, collected by the TOP500 website. Multicore processors continue to present challenges to the development of fast and robust numerical software due to the increasing levels of hardware parallelism and widening gap between core and memory speeds. In this context, the difficulty in developing new algorithms for the scientific community resides in the combination of two goals: achieving high performance while maintaining the accuracy of the numerical algorithm. This paper proposes a new approach for computing the LU factorization in parallel on multicore architectures, which not only improves the overall performance but also sustains the numerical quality of the standard LU factorization algorithm with partial pivoting. While the update of the trailing submatrix is computationally intensive and highly parallel, the inherently problematic portion of the LU factorization is the panel factorization due to its memory-bound characteristic as well as the atomicity of selecting the appropriate pivots. Our approach uses a parallel fine-grained recursive formulation of the panel factorization step and implements the update of the trailing submatrix with the tile algorithm. Based on conflict-free partitioning of the data and lockless synchronization mechanisms, our implementation lets the overall computation flow naturally without contention. The dynamic runtime system called QUARK is then able to schedule tasks with heterogeneous granularities and to transparently introduce algorithmic lookahead. The performance results of our implementation are competitive compared to the currently available software packages and libraries. For example

  12. Motivational Factors Contributing to Turkish High School Students' Achievement in Gases and Chemical Reactions

    Kadioglu, Cansel; Uzuntiryaki, Esen

    2008-01-01

    This study aimed to investigate the contribution of motivational factors to 10th grade students' achievement in gases and chemical reactions in chemistry. Three hundred fifty nine 10th grade students participated in the study. The Gases and Chemical Reactions Achievement Test and the Motivated Strategies for Learning Questionnaire were…

  13. Social Adaptation and Its Relationship to Achievement Motivation among High School Students in Jordan

    AlZboon, Saleem Odeh

    2013-01-01

    The study amid at exploring and detecting the level of social adaptation and its relationship with the achievement motivation of the secondary school students in Jordan, the study sample consisted of 495 secondary school students in the province of Jerash, and to achieve the objective of this study comes the development of two tools: the first one…

  14. Longitudinal Analysis of Chinese High School Student's Stress in School and Academic Achievement

    Liu, Yangyang; Lu, Zuhong

    2011-01-01

    In previous research, few studies have examined the effects of adolescents' stress in school on the change rates of their academic achievement. In the present study, we seek to examine the longitudinal relationships between adolescents' stress in school and the change rates of their academic achievement. The results indicated that for those whose…

  15. Relationship between High School Students' Achievement Goal Orientation and Academic Motivation for Learning Biology: A Path Analysis

    Yerdelen, Sündüs; Kafkas Üniversitesi, Eğitim Fakültesi, İlköğretim Bölümü; Aydın, Solmaz; Kafkas Üniversitesi, Eğitim Fakültesi, İlköğretim Bölümü; Gürbüzoğlu Yalmancı, Sibel; Kafkas Üniversitesi, Eğitim Fakültesi, OFMAE; Göksu, Volkan; Kafkas Üniversitesi, Eğitim Fakültesi, İlköğretim Bölümü

    2014-01-01

    This study aimed to investigate the relationship between high school students' achievement goal orientation and academic motivation for learning biology. The sample of the study consisted of 281 students taking biology course at science and Anatolian high schools in Kars. Survey method was employed in the study, and "Academic motivation scale for learning biology (AMSLB)" and "Achievement goal orientation questionnaire" were used as data gathering tools. According to the results of the study,...

  16. Needs-Satisfaction, Motivation, and Achievement in High School Students: Testing Predictive Models by Gender and Ethnicity

    Bialis-White, Lionel Henry

    2013-01-01

    Student motivation is one proposed contributing factor to disparate rates of high school achievement. Guided by self-determination theory (SDT; Ryan & Deci, 2000a), the purpose of the present study is to investigate whether a process model of the relationship between motivation and achievement varied by gender and racial subsamples of students within one large high school (see Figure 1). First, I examined the reliability and structural validity of the measures within the model. Second, I e...

  17. Execution Plans for Cyber Foraging

    Kristensen, Mads Darø

    2008-01-01

    Cyber foraging helps small devices perform heavy tasks by opportunistically discovering and utilising available resources (such as computation, storage, bandwidth, etc.) held by larger, nearby peers. This offloading is done in an ad-hoc manner, as larger machines will not always be within reach. In...

  18. Squirrel Foraging Preferences: Gone Nuts?

    Darling, Randi A.

    2007-01-01

    This field exercise examines the feeding preferences of Gray Squirrels ("Sciurus carolinensis"). Students present squirrels with a variety of food types in a cafeteria-style arrangement in order to test hypotheses about foraging preferences. This exercise, which is appropriate for introductory biology, ecology, and animal behavior classes, is…

  19. Foraging Activity Pattern Is Shaped by Water Loss Rates in a Diurnal Desert Rodent.

    Levy, Ofir; Dayan, Tamar; Porter, Warren P; Kronfeld-Schor, Noga

    2016-08-01

    Although animals fine-tune their activity to avoid excess heat, we still lack a mechanistic understanding of such behaviors. As the global climate changes, such understanding is particularly important for projecting shifts in the activity patterns of populations and communities. We studied how foraging decisions vary with biotic and abiotic pressures. By tracking the foraging behavior of diurnal desert spiny mice in their natural habitat and estimating the energy and water costs and benefits of foraging, we asked how risk management and thermoregulatory requirements affect foraging decisions. We found that water requirements had the strongest effect on the observed foraging decisions. In their arid environment, mice often lose water while foraging for seeds and cease foraging even at high energetic returns when water loss is high. Mice also foraged more often when energy expenditure was high and for longer times under high seed densities and low predation risks. Gaining insight into both energy and water balance will be crucial to understanding the forces exerted by changing climatic conditions on animal energetics, behavior, and ecology. PMID:27420785

  20. Evidence for foraging -site fidelity and individual foraging behavior of pelagic cormorants rearing chicks in the gulf of Alaska

    Kotzerka, J.; Hatch, Shyla A.; Garthe, S.

    2011-01-01

    The Pelagic Cormorant (Phalacrocorax pelagicus) is the most widespread cormorant in the North Pacific, but little is known about its foraging and diving behavior. However, knowledge of seabirds' foraging behavior is important to understanding their function in the marine environment. In 2006, using GPS dataloggers, we studied the foraging behavior of 14 male Pelagic Cormorants rearing chicks on Middleton Island, Alaska. For foraging, the birds had high fidelity to a small area 8 km north of the colony. Within that area, the cormorants' diving activity was of two distinct kinds-near-surface dives (1-6 m) and benthic dives (28-33 m). Individuals were consistent in the depths of their dives, either mostly shallow or mostly deep. Few showed no depth preference. Dive duration, time at maximum depth, and pauses at the water surface between consecutive dives were shorter for shallow dives than for deep dives. The cormorants made dives of both types throughout the day, but the frequency of deep dives increased toward evening. Maximum foraging range was 9 km; maximum total distance traveled per trip was 43.4 km. Trip durations ranged from 0.3 to 7.7 hr. Maximum depth of a dive was 42.2 m, and duration of dives ranged from 4 to 120 sec. We found that Pelagic Cormorants at Middleton Island were faithful to one particular foraging area and individuals dived in distinct patterns. Distinct, specialized foraging behavior may be advantageous in reducing intra- and interspecific competition but may also render the species vulnerable to changing environmental conditions. Copyright ?? The Cooper Ornithological Society 2011.

  1. Anion control as a strategy to achieve high-mobility and high-stability oxide thin-film transistors.

    Kim, Hyun-Suk; Jeon, Sang Ho; Park, Joon Seok; Kim, Tae Sang; Son, Kyoung Seok; Seon, Jong-Baek; Seo, Seok-Jun; Kim, Sun-Jae; Lee, Eunha; Chung, Jae Gwan; Lee, Hyungik; Han, Seungwu; Ryu, Myungkwan; Lee, Sang Yoon; Kim, Kinam

    2013-01-01

    Ultra-definition, large-area displays with three-dimensional visual effects represent megatrend in the current/future display industry. On the hardware level, such a "dream" display requires faster pixel switching and higher driving current, which in turn necessitate thin-film transistors (TFTs) with high mobility. Amorphous oxide semiconductors (AOS) such as In-Ga-Zn-O are poised to enable such TFTs, but the trade-off between device performance and stability under illumination critically limits their usability, which is related to the hampered electron-hole recombination caused by the oxygen vacancies. Here we have improved the illumination stability by substituting oxygen with nitrogen in ZnO, which may deactivate oxygen vacancies by raising valence bands above the defect levels. Indeed, the stability under illumination and electrical bias is superior to that of previous AOS-based TFTs. By achieving both mobility and stability, it is highly expected that the present ZnON TFTs will be extensively deployed in next-generation flat-panel displays. PMID:23492854

  2. Microalgal growth with intracellular phosphorus for achieving high biomass growth rate and high lipid/triacylglycerol content simultaneously.

    Wu, Yin-Hu; Yu, Yin; Hu, Hong-Ying

    2015-09-01

    Nutrient deprivation is a commonly-used trigger for microalgal lipid accumulation, but its adverse impact on microalgal growth seems to be inevitable. In this study, Scenedesmus sp. LX1 was found to show similar physiological and biochemical variation under oligotrophic and eutrophic conditions during growth with intracellular phosphorus. Under both conditions microalgal chlorophyll content and photosynthesis activity was stable during this growth process, leading to significant increase of single cell weight and size. Therefore, while algal density growth rate dropped significantly to below 1.0 × 10(5)cells mL(-1) d(-1) under oligotrophic condition, the biomass dry weight growth rate still maintained about 40 mg L(-1) d(-1). Meanwhile, the lipid content in biomass and triacylglycerols (TAGs) content in lipids increased significantly to about 35% and 65%, respectively. Thus, high biomass growth rate and high lipid/TAG content were achieved simultaneously at the late growth phase with intracellular phosphorus. Besides, microalgal biomass produced was rich in carbohydrate with low protein content. PMID:26056779

  3. Potency Of Clitoria Ternatea As Forage For Livestock

    Endang Sutedi

    2013-06-01

    Full Text Available Availability of forage is one of the factors determining the success of ruminant livestock production, especially during drought that resulting in poor livestock condition. Forage legume is an important group of forage plants, containing high nutritive value. One of the legume plants which potential as ruminant feed is Clitoria ternatea. This plant can grow well in all types of soil and dry conditions, also produces seed continously. The production of forage was 25-29 ton DM/ha with seed production was 2.2 ton DM/ha per harvest (42 day cutting interval. The crude protein and crude fiber contents of C. ternatea leaf were 21.5 and 29%, respectively. Meanwhile, the crude protein, crude fat and sugar contents of C. ternatea seed were 25-38,10 and 5%, respectively. This plant can be fed to ruminant as fresh forage or hay with no negative effect on growth performance of animal. The average daily gain of cattle grazing on mixture of Brachiaria mutica grass and C. ternatea was 680 g/day. The value of DM and OM digestibilities of C. ternatea in cattle were 50.15 and 53.47%, respectively. Feeding C. ternatea to dairy cow impoved the content of fat and total solid of milk, meanwhile feeding it to male sheep improved quality of semen.

  4. Achievement and Social Ascription: A Comparison of Public and Private High Schools.

    Bickel, Robert

    1986-01-01

    Public and private schooling have a roughly uniform effect on achievement, but variability among students' home and neighborhood environments mask the leveling effect. Includes an historical discussion of egalitarianism and stratification in American education. (PS)

  5. Family socioeconomic status, family health, and changes in students' math achievement across high school: A mediational model.

    Barr, Ashley Brooke

    2015-09-01

    In response to recent calls to integrate understandings of socioeconomic disparities in health with understandings of socioeconomic disparities in academic achievement, this study tested a mediational model whereby family socioeconomic status predicted gains in academic achievement across high school through its impact on both student and parent health. Data on over 8000 high school students in the U.S. were obtained from wave 1 (2009-2010) and wave 2 (2012) of the High School Longitudinal Study of 2009 (HSLS:09), and structural equation modeling with latent difference scores was used to determine the role of family health problems in mediating the well-established link between family SES and gains in academic achievement. Using both static and dynamic indicators of family SES, support was found for this mediational model. Higher family SES in 9th grade reduced the probability of students and their parents experiencing a serious health problem in high school, thereby promoting growth in academic achievement. In addition, parent and student health problems mediated the effect of changes in family SES across high school on math achievement gains. Results emphasize the importance of considering the dynamic nature of SES and that both student and parent health should be considered in understanding SES-related disparities in academic achievement. This relational process provides new mechanisms for understanding the intergenerational transmission of socioeconomic status and the status attainment process more broadly. PMID:26189011

  6. What’s Past is Prologue: Relations Between Early Mathematics Knowledge and High School Achievement

    Watts, TW; Duncan, GJ; Siegler, RS; Davis-Kean, PE

    2014-01-01

    © 2014 AERA. Although previous research has established the association between early-grade mathematics knowledge and later mathematics achievement, few studies have measured mathematical skills prior to school entry, and few have investigated the predictive power of early gains in mathematics ability. The current paper relates mathematical skills measured at 54 months to adolescent mathematics achievement using multisite longitudinal data. We find that preschool mathematics ability predicts ...

  7. A strategy for achieving manufacturing statistical process control within a highly complex aerospace environment

    Veira, Adryan; Khan, Khurshid; Farrell, Ian

    2013-01-01

    This paper presents a strategy to achieve process control and overcome the previously mentioned industry constraints by changing the company focus to the process as opposed to the product. The strategy strives to achieve process control by identifying and controlling the process parameters that influence process capability followed by the implementation of a process control framework that marries statistical methods with lean business process and change management principles. The reliability ...

  8. Contrasting Cellularity and Fatty Acid Composition in Fat Depots from Alentejana and Barrosã Bovine Breeds Fed High and Low Forage Diets

    Ana S.H. Costa, Paula A. Lopes, Marta Estevão, Susana V. Martins, Susana P. Alves, Rui M.A. Pinto, Hugo Pissarra, Jorge J. Correia, Mário Pinho, Carlos M.G.A. Fontes, José A.M. Prates

    2012-01-01

    Full Text Available During the finishing phase of bovines, large amounts of subcutaneous and visceral fats are deposited leading to production inefficiencies with major impact on meat quality. A better understanding of the cellularity features of the main fat depots could provide strategies for adipose tissue manipulation. This study assessed the effect of feeding diets with distinct forage to concentrate ratios on the cellularity of two fat depots of beef cattle and their implications on the fatty acid profile. Thus, two phylogenetically distant Portuguese bovine breeds, Alentejana and Barrosã, were selected. The results did not show differences in subcutaneous fat deposition nor in visceral fat depots partitioning. Plasma adipokines concentration failed to show a consistent relationship with fatness, as leptin remained constant in all experimental groups, whereas interleukin-6 was influenced by breed. Fat depot seems to determine the area and number of adipocytes, with larger adipocytes and a lower number of cells in subcutaneous fat than in mesenteric fat. Neither breed nor diet influenced adipocytes area and number. The contents of total fatty acids, partial sums of fatty acids and conjugated linoleic acid isomeric profile were affected by breed and fat depot. The incorporation of saturated fatty acids (SFA, trans fatty acids, polyunsaturated fatty acids (PUFA and branched chain fatty acids (BCFA was higher in mesenteric fat depot, whereas subcutaneous fat depot had greater percentages of monounsaturated fatty acids (MUFA. In addition, SFA and MUFA proportions seem to be breed-related. In spite of the less relevant role of diet, the percentages of PUFA and BCFA were influenced by this factor. Under these experimental conditions, the effect of fat depot on cellularity and fatty acid composition prevails over breed or diet, as reinforced by the principal component analysis.

  9. Forage Polyphenol Oxidase and Ruminant Livestock Nutrition

    Michael Richard F. Lee

    2014-12-01

    Full Text Available Polyphenol oxidase (PPO is associated with the detrimental effect of browning fruit and vegetables, however interest within PPO containing forage crops has grown since the brownng reaction was associated with reduced nitrogen (N losses in silo and the rumen. The reduction in protein breakdown in silo of red clover (high PPO forage increased the quality of protein, improving N-use efficiency (NUE when fed to ruminants. A further benefit of red clover silage feeding is a significant reduction in lipolysis in silo and an increase in the deposition of beneficial C18 polyunsaturated fatty acid (PUFA in animal products, which has also been linked to PPO activity. PPOs protection of plant protein and glycerol based-PUFA in silo is related to the deactivation of plant proteases and lipases. This deactivation occurs through PPO catalysing the conversion of diphenols to quinones which bind with cellular nucleophiles such as protein reforming a protein-bound phenol (PBP. If the protein is an enzyme the complexing denatures the enzyme. However, PPO is inactive in the anaerobic rumen and therefore any subsequent protection of plant protein and glycerol based-PUFA in the rumen must be as a result of events that occurred to the forage pre-ingestion. Reduced activity of plant proteases and lipases would have little effect on NUE and glycerol based-PUFA in the rumen due to the greater concentration of rumen microbial proteases and lipases. The mechanism for PPOs protection of plant protein in the rumen is a consequence of complexing plant protein, rather than protease deactivation per se. These complexed proteins reduce protein digestibility in the rumen and subsequently increase un-degraded dietary protein flow to the small intestine. The mechanism for protecting glycerol-based PUFA has yet to be fully elucidated but may be associated with entrapment within PBP reducing access to microbial lipases or differences in rumen digestion kinetics of red clover.

  10. Multimodal floral signals and moth foraging decisions.

    Jeffrey A Riffell

    Full Text Available BACKGROUND: Combinations of floral traits - which operate as attractive signals to pollinators - act on multiple sensory modalities. For Manduca sexta hawkmoths, how learning modifies foraging decisions in response to those traits remains untested, and the contribution of visual and olfactory floral displays on behavior remains unclear. METHODOLOGY/PRINCIPAL FINDINGS: Using M. sexta and the floral traits of two important nectar resources in southwestern USA, Datura wrightii and Agave palmeri, we examined the relative importance of olfactory and visual signals. Natural visual and olfactory cues from D. wrightii and A. palmeri flowers permits testing the cues at their native intensities and composition - a contrast to many studies that have used artificial stimuli (essential oils, single odorants that are less ecologically relevant. Results from a series of two-choice assays where the olfactory and visual floral displays were manipulated showed that naïve hawkmoths preferred flowers displaying both olfactory and visual cues. Furthermore, experiments using A. palmeri flowers - a species that is not very attractive to hawkmoths - showed that the visual and olfactory displays did not have synergistic effects. The combination of olfactory and visual display of D. wrightii, however - a flower that is highly attractive to naïve hawkmoths - did influence the time moths spent feeding from the flowers. The importance of the olfactory and visual signals were further demonstrated in learning experiments in which experienced moths, when exposed to uncoupled floral displays, ultimately chose flowers based on the previously experienced olfactory, and not visual, signals. These moths, however, had significantly longer decision times than moths exposed to coupled floral displays. CONCLUSIONS/SIGNIFICANCE: These results highlight the importance of specific sensory modalities for foraging hawkmoths while also suggesting that they learn the floral displays as

  11. Achievement Emotions as Predictors of High School Science Success Among African-American and European American Students

    Bowe, Marilyn Louise Simmons

    The literature includes few studies of the interrelations of achievement goals and achievement emotions with respect to minority students and science achievement. The objective of this study was to test the control-value theory (CVT) of achievement emotions to determine if the eight discrete achievement emotions would be predictive of test scores on the High School Graduation Test (GHSGT)-Science for African-American compared to European-American science students. Convenience cluster sampling was employed to select 160 students who were all juniors in the same public high school at the time that they took the GHSGT-Science. The central research question for this study aimed to uncover whether any of the eight achievement emotions identified in CVT would contribute significantly to the predictability of science achievement as measured by GHSGT-Science scores. Data were collected using a nonexperimental, cross sectional design survey. Data were analyzed using a hierarchal, forced entry, multiple regression analysis. Key results indicated that the eight achievement emotions were predictive of GHSGT-Science score outcomes. Positive social change at the individual level could reflect a boost in confidence for African American science students and help decrease the achievement gap in science, technology, engineering, and mathematics (STEM) endeavors between European Americans and African-American students. Educators may consider the importance of achievement emotions in science outcomes by including social emotional learning (SEL) as a part of the regular science curriculum. Future researchers should repeat the study in a school district where the population is available to support the desired cluster sample of equal parts European Americans to African Americans and male to female students.

  12. Corn in consortium with forages

    Cássia Maria de Paula Garcia

    2013-12-01

    Full Text Available The basic premises for sustainable agricultural development with focus on rural producers are reducing the costs of production and aggregation of values through the use crop-livestock system (CLS throughout the year. The CLS is based on the consortium of grain crops, especially corn with tropical forages, mainly of the genus Panicum and Urochloa. The study aimed to evaluate the grain yield of irrigated corn crop intercropped with forage of the genus Panicum and Urochloa. The experiment was conducted at the Fazenda de Ensino, Pesquisa e Extensão – FEPE  of the Faculdade de Engenharia - UNESP, Ilha Solteira in an Oxisol in savannah conditions and in the autumn winter of 2009. The experimental area was irrigated by a center pivot and had a history of no-tillage system for 8 years. The corn hybrid used was simple DKB 390 YG at distances of 0.90 m. The seeds of grasses were sown in 0.34 m spacing in the amount of 5 kg ha-1, they were mixed with fertilizer minutes before sowing  and placed in a compartment fertilizer seeder and fertilizers were mechanically deposited in the soil at a depth of 0.03 m. The experimental design used was a randomized block with four replications and five treatments: Panicum maximum cv. Tanzania sown during the nitrogen fertilization (CTD of the corn; Panicum maximum cv. Mombaça sown during the nitrogen fertilization (CMD of the corn; Urochloa brizantha cv. Xaraés sown during the occasion of nitrogen fertilization (CBD of the corn; Urochloa ruziziensis cv. Comumsown during the nitrogen fertilization (CRD of the corn and single corn (control. The production components of corn: plant population per hectare (PlPo, number of ears per hectare (NE ha-1, number of rows per ear (NRE, number of kernels per row on the cob (NKR, number of grain in the ear (NGE and mass of 100 grains (M100G were not influenced by consortium with forage. Comparing grain yield (GY single corn and maize intercropped with forage of the genus Panicum

  13. Foraging decisions in wild versus domestic Mus musculus: What does life in the lab select for?

    Troxell-Smith, Sandra M; Tutka, Michal J; Albergo, Jessica M; Balu, Deebika; Brown, Joel S; Leonard, John P

    2016-01-01

    What does domestication select for in terms of foraging and anti-predator behaviors? We applied principles of patch use and foraging theory to test foraging strategies and fear responses of three strains of Mus musculus: wild-caught, control laboratory, and genetically modified strains. Foraging choices were quantified using giving-up densities (GUDs) under three foraging scenarios: (1) patches varying in microhabitat (covered versus open), and initial resource density (low versus high); (2) daily variation in auditory cues (aerial predators and control calls); (3) patches with varying seed aggregations. Overall, both domestic strains harvested significantly more food than wild mice. Each strain revealed a significant preference for foraging under cover compared to the open, and predator calls had no detectable effects on foraging. Both domestic strains biased their harvest toward high quality patches; wild mice did not. In terms of exploiting favorable and avoiding unfavorable distributions of seeds within patches, the lab strain performed best, the wild strain worst, and the mutant strain in between. Our study provides support for hypothesis that domestic animals have more energy-efficient foraging strategies than their wild counterparts, but retain residual fear responses. Furthermore, patch-use studies can reveal the aptitudes and priorities of both domestic and wild animals. PMID:26548716

  14. Investigate Factor Effecting Of Students’ Achievement on High School Entrance Exam-(SBS Respect to the Different Variables

    Mustafa METİN

    2013-04-01

    Full Text Available The aim of study is to investigate factor affecting of secondary school students’ achievement on high school entrance exam (SBS respect to the different variables. The study was carried out at fall semester of 2012 with 991 students educating primary schools in Artvin. In this study survey method was used and data gathered with questionnaire consists of 40 items. As a result of study, it was determinate that effects of family, educational facilities, teachers and personal characters on students’ achievement are at high level. There is no different between gender and students achievement (p>0.05, although there are different between grade level, family incomes, graduation types of mother and father and students achievement (p<0.05.

  15. Markets, voucher subsidies and free nets combine to achieve high bed net coverage in rural Tanzania

    Gerrets Rene PM

    2008-06-01

    Full Text Available Abstract Background Tanzania has a well-developed network of commercial ITN retailers. In 2004, the government introduced a voucher subsidy for pregnant women and, in mid 2005, helped distribute free nets to under-fives in small number of districts, including Rufiji on the southern coast, during a child health campaign. Contributions of these multiple insecticide-treated net delivery strategies existing at the same time and place to coverage in a poor rural community were assessed. Methods Cross-sectional household survey in 6,331 members of randomly selected 1,752 households of 31 rural villages of Demographic Surveillance System in Rufiji district, Southern Tanzania was conducted in 2006. A questionnaire was administered to every consenting respondent about net use, treatment status and delivery mechanism. Findings Net use was 62.7% overall, 87.2% amongst infants (0 to1 year, 81.8% amongst young children (>1 to 5 years, 54.5% amongst older children (6 to 15 years and 59.6% amongst adults (>15 years. 30.2% of all nets had been treated six months prior to interview. The biggest source of nets used by infants was purchase from the private sector with a voucher subsidy (41.8%. Half of nets used by young children (50.0% and over a third of those used by older children (37.2% were obtained free of charge through the vaccination campaign. The largest source of nets amongst the population overall was commercial purchase (45.1% use and was the primary means for protecting adults (60.2% use. All delivery mechanisms, especially sale of nets at full market price, under-served the poorest but no difference in equity was observed between voucher-subsidized and freely distributed nets. Conclusion All three delivery strategies enabled a poor rural community to achieve net coverage high enough to yield both personal and community level protection for the entire population. Each of them reached their relevant target group and free nets only temporarily

  16. Students' attitude to homework: how is homework perceived by high-achieving students and those with learning disabilities

    Trobec, Nika

    2013-01-01

    Homework assignments have many positive educational effects, which are achieved only when they are regularly performed and completed. While doing homework, students are under the influence of various external and internal factors that affect its utility. Many of them experience homework-related problems in one or more areas which are described in theoretical part. Aim of the empirical survey was to do a research on homework practices of students with learning disabilities and high achieving s...

  17. Case Studies of Factors Affecting the Motivation of Musical High Achievers to Learn Music in Hong Kong

    Leung, Bo Wah; McPherson, Gary E.

    2011-01-01

    This article reports on the personal beliefs and attitudes of highly motivated Hong Kong school-age subjects who studied music. A total of 24 participants who demonstrated high achievement and interest in learning music were interviewed. Content analysis of the interview data was performed to elucidate four topics: background information about the…

  18. Gender Differences in Korean High School Students' Science Achievements and Attitudes towards Science in Three Different School Settings

    Bang, EunJin; Baker, Dale R.

    2013-01-01

    This study analysed the effect of high schools' gender organization on Korean tenth-grade students' science achievements, and their attitudes towards science. The high schools involved included an all-male institution, an all-female institution, and a co-educational institution. Three schools, three principals, three science teachers, and 302…

  19. Differential regulation of the foraging gene associated with task behaviors in harvester ants

    Kleeman Lindsay

    2011-08-01

    Full Text Available Abstract Background The division of labor in social insect colonies involves transitions by workers from one task to another and is critical to the organization and ecological success of colonies. The differential regulation of genetic pathways is likely to be a key mechanism involved in plasticity of social insect task behavior. One of the few pathways implicated in social organization involves the cGMP-activated protein kinase gene, foraging, a gene associated with foraging behavior in social insect species. The association of the foraging gene with behavior is conserved across diverse species, but the observed expression patterns and proposed functions of this gene vary across taxa. We compared the protein sequence of foraging across social insects and explored whether the differential regulation of this gene is associated with task behaviors in the harvester ant, Pogonomyrmex occidentalis. Results Phylogenetic analysis of the coding region of the foraging gene reveals considerable conservation in protein sequence across insects, particularly among hymenopteran species. The absence of amino acid variation in key active and binding sites suggests that differences in behaviors associated with this gene among species may be the result of changes in gene expression rather than gene divergence. Using real time qPCR analyses with a harvester ant ortholog to foraging (Pofor, we found that the brains of harvester ant foragers have a daily fluctuation in expression of foraging with mRNA levels peaking at midday. In contrast, young workers inside the nest have low levels of Pofor mRNA with no evidence of daily fluctuations in expression. As a result, the association of foraging expression with task behavior within a species changes depending on the time of day the individuals are sampled. Conclusions The amino acid protein sequence of foraging is highly conserved across social insects. Differences in foraging behaviors associated with this gene among

  20. The role of knowledge management in achieving harmonized high level of nuclear safety

    Full text: The challenge for governments in the nuclear safety regulatory area is to maintain high standards of safety while ensuring that regulation is effective and focused on real risks. We speak more and more about the need for harmonization, one of the reasons probably is that the context in which nuclear regulators work has changed. Protecting citizens and the environment is a more demanding task in the 21st century. Nuclear operators must perform more efficiently and be more innovative in a highly integrated international economy. Perhaps not surprisingly, regulators can hear from the industry that the current regulatory system often acts as a constraint to innovation, competitiveness, investment and trade. Regulatory oversight was earlier very much connected to inspection and review of the technical solutions presented for various purposes. Today it is instead an outspoken strategy by many regulators to move more towards inspection and reviewing of the work processes by which nuclear power plants themselves ensure that their safety management activities are covering and efficient. The concept of risk informed regulation has also been associated to an allocation of resources for regulatory activities, which is governed by their importance for safety. The enlarged EU is the world's leading nuclear electricity generator. Development in regulatory approaches and priorities due to changing economic conditions to produce electricity, ageing and modernization of existing reactors and due to human assets takes place in countries with nuclear power. The EURATOM Treaty calls for the establishment of 'uniform safety standards' in the EU, at the same time, the sovereign power of national governments to manage their energy sectors is affirmed. A compromise must be found which maintains the highest safety standards for EU citizens, but respects these two positions. The nuclear safety regulatory requirements are always anchored in the national legislation, because they

  1. Relations among Beliefs about Epistemology, Ability Conceptions, and Achievement in High School Physical Education Students

    Ken Lodewyk

    2009-01-01

    While the critical role of knowledge in physical education performance is well-documented, there is little research into the role that students' beliefs about what knowing is and how they come to know relate to their achievement in physical education. The purpose of this study was to discover relations between beliefs about epistemology, ability…

  2. Mathematically Gifted Students and High Achievement: The Role of Motivation and Classroom Structure

    Lüftenegger, Marko; Kollmayer, Marlene; Bergsmann, Evelyn; Jöstl, Gregor; Spiel, Christiane; Schober, Barbara

    2015-01-01

    One of the most intriguing questions for those who study intellectually gifted students is why some of them reach peak performances at school and others don't. Moderator theories of giftedness assume that domain-specific gifts are transformed into achievement in a process influenced by non-cognitive and environmental variables. Thus, the current…

  3. High School Teachers' Perceptions of School Change and Its Implications for Student Achievement

    Mitchell, Anthony J.

    2010-01-01

    This study attempted to observe if there was a statistical significant relationship between perceptions of educational change and student achievement. The independent variables that represented perceptions of educational change included: community pressure for change, faculty anxiety to change, faculty openness to change, principal anxiety to…

  4. Effect of Blended Learning Environment Model on High School Students' Academic Achievement

    Kazu, Ibrahim Yasar; Demirkol, Mehmet

    2014-01-01

    This study analyzes the students' academic performance by comparing the blended learning environment and traditional learning environment. It has been observed whether there is a significant difference between the academic achievement grade dispersions and the male-female students' grades. The study has been carried out in Diyarbakir…

  5. Factors Affecting the Achievement of High School Students in Beginning Computer Science Courses.

    Guinan, Tricia; Stephens, Larry

    1988-01-01

    Considers three questions regarding computer science courses: (1) Can performance be predicted?; (2) Does a solid mathematical background provide the student with an advantage?; and (3) Is gender a factor in performance or aptitude? Reports a strong math background was related to achievement in a beginning course while gender was not related. (MVL)

  6. Impacts of Comprehensive Reading Instruction on Diverse Outcomes of Low- and High-Achieving Readers

    Guthrie, John T.; McRae, Angela; Coddington, Cassandra S.; Klauda, Susan Lutz; Wigfield, Allan; Barbosa, Pedro

    2009-01-01

    Low-achieving readers in Grade 5 often lack comprehension strategies, domain knowledge, word recognition skills, fluency, and motivation to read. Students with such multiple reading needs seem likely to benefit from instruction that supports each of these reading processes. The authors tested this expectation experimentally by comparing the…

  7. Three Dopaminergic Polymorphisms Are Associated with Academic Achievement in Middle and High School

    Beaver, Kevin M.; Vaughn, Michael G.; Wright, John Paul; DeLisi, Matt; Howard, Matthew O.

    2010-01-01

    Although academic achievement is a heritable construct, to date research has yet to explore its molecular genetic underpinnings. Drawing on data from the National Longitudinal Study of Adolescent Health, the current longitudinal study investigated the associations between polymorphisms in three dopaminergic genes (DAT1, DRD2, and DRD4) and…

  8. The Influence of Mathematics Anxiety in Middle and High School Students Math Achievement

    Al Mutawah, Masooma Ali

    2015-01-01

    Math anxiety has been the focus of much psychological and educational research in the past few years, there are many international studies showing that mathematics anxiety is an influence on student's achievements in school, but little research has been done about this issue in Bahrain. Bahrain is a country in the Arabian Gulf region, its economic…

  9. What's Past Is Prologue: Relations between Early Mathematics Knowledge and High School Achievement

    Watts, Tyler W.; Duncan, Greg J.; Siegler, Robert S.; Davis-Kean, Pamela E.

    2014-01-01

    Although previous research has established the association between early-grade mathematics knowledge and later mathematics achievement, few studies have measured mathematical skills prior to school entry, and few have investigated the predictive power of early gains in mathematics ability. The current paper relates mathematical skills measured at…

  10. Nutritive value response of forage chicory cultivars to phosphorus fertility

    Forage chicory (Cichorium intybus L.) is a productive plant that appears particularly well suited to improving summer yield of pastures in the USA. Poor palatability of some chicory cultivars in locations with low soil phosphorus fertility has been linked to high levels of sesquiterpene lactones, b...

  11. Yield and persistence response of forage chicory to phosphorus fertility

    Forage chicory (Cichorium intybus) is a productive plant that appears particularly well suited to improving summer yield of pastures in the USA. Poor palatability of some chicory cultivars in locations with low soil phosphorus fertility has been linked to high levels of sesquiterpene lactone, a bit...

  12. Wild Bee Community Composition and Foraging Behaviour in Commercial Strawberries

    Ahrenfeldt, Erica Juel

    were ground-nesting polylectic solitary species that are known to forage in the family Rosaceae, to which strawberry belong, which indicate that the bees sampled are a source of pollination in strawberries (I, II). Furthermore, the high proportion of polylectic bees found in Danish strawberry fields...

  13. Survey of diverse wheat lines for forage tannins

    Winter wheat (Triticum aestivum L.) is the main cool-season forage grown in the southern Great Plains. The high digestibility, soluble protein, and intake of lush growing wheat contribute to pasture bloat, leading to substantial economic loss. In the 1999-2000 grazing season in OK 40% of animal deat...

  14. In situ Rumen Degradation Kinetics of High-Protein Forage Crops in Temperate Climates Cinética de Degradación Ruminal in situ en Forrajes de Alto Contenido Proteico en Clima Templado

    Ximena Valderrama L.

    2011-12-01

    Full Text Available The present study was conducted to evaluate the nutritional value and in situ degradation kinetics of eight high protein forage crops: alfalfa (Medicago sativa L., forage oat (Avena sativa L., mixed pasture, and ryegrass (Lolium multiflorum Lam. pasture in early vegetative stages, two forage lupins (Lupinus albus L. in early bloom stages, sugar beet (Beta vulgaris L. and kale (Brassica napus var. pabularia (DC. Rchb. leaves at root maturity. Dry matter (DM and crude protein (CP degradation kinetics were evaluated by the nylon bag technique through the in situ procedure described by 0rskov and MacDonald (1979 using three ruminally cannulated sheep. Chemical composition of the forage crops showed on average 13.7% DM; 21.4% CP; 31.5% neutral detergent fiber (NDF; 17.7% crude fiber (CF, 80.6% digestibility of organic matter (DOMD and 12.13 MJ kg-1 metabolizable energy (ME. The high total degradability of forage crops reported here (> 87% DM; > 93% CP can be associated with the presence of large quantities of fraction a (> 34% DMa; > 29% CPa and high degradability of fraction b, resulting in low amounts of undegradable fraction (U (7.02% DM and 3.55% CP. Correlations between CPb and DMb degradability (r = 0.79 and CPc and DMc degradation rates (r = 0.78 were high, however differences in c were not explained by differences in CP or NDF contents, nor by the amounts of a or b fractions. Degradation for DM and CP during the first 6 h of incubation was strongly and inversely correlated to b (36 h (r = 0.93 (P El presente estudio se desarrolló con el objetivo de evaluar el valor nutricional y la cinética de degradación in situ de ocho forrajes de alto valor proteico: alfalfa (Medicago sativa L., avena (Avena sativa L., pastos mixtos y pastos de ballica (Lolium multiflorum Lam., en las primeras etapas vegetativas, dos lupinos forrajeros (Lupinus albus L. en etapas inicio de la floración, hojas de remolacha azucarera (Beta vulgaris L. y de col (Brassica

  15. The evolution of foraging rate across local and geographic gradients in predation risk and competition.

    Urban, Mark C; Richardson, Jonathan L

    2015-07-01

    Multiple theories predict the evolution of foraging rates in response to environmental variation in predation risk, intraspecific competition, time constraints, and temperature. We tested six hypotheses for the evolution of foraging rate in 24 spotted salamander (Ambystoma maculatum) populations from three latitudinally divergent sites using structural equation models derived from theory and applied to our system. We raised salamander larvae in a common-garden experiment and then assayed foraging rate under controlled conditions. Gape-limited predation risk from marbled salamanders solely explained foraging rate variation among populations at the southern site, which was dominated by this form of selection. However, at the middle and northern sites, populations evolved different foraging rates depending on their unique responses to local intraspecific density. The coupling of gape-limited predation risk from marbled salamanders and high intraspecific density at the middle site jointly contributed to selection for rapid foraging rate. At the northernmost site, intraspecific density alone explained 97% of the interpopulation variation in foraging rate. These results suggest that foraging rate has evolved multiple times in response to varying contributions from predation risk and intraspecific competition. Predation risk often varies along environmental gradients, and, thus, organisms might often shift evolutionary responses from minimizing predation risk to maximizing intraspecific competitive performance. PMID:26098352

  16. THE EXAMINATION OF ACHIEVEMENT OF STUDENTS AT THE DEPARTMENT OF MUSICAL EDUCATION BY THE TYPES OF HIGH SCHOOL THEY GRADUATED

    ECE, Ahmet Serkan; BİLGİN, Ahmet Süleyman

    2007-01-01

    In this research students attending the Department of Musical Education were examined for any significant difference between their scores on the musical aptitude test and their achievement scores in their disciplinary lessons in terms of their high school background: ?Anatolian Fine Arts High School? and ?Other High Schools? Datas for this research consisted of the scores students were given at the musical aptitude test for enrolment to Abant İzzet Baysal University Faculty of Education Dep...

  17. Utilization of male sterility in forage crops

    The genetic nature of male sterility in forage crops was reviewed. Many workers have suggested that hybrids in forage crops are quite promising. First, the selection of the most desirable parental genotype from a large original population is improtant in heterosis breeding programs. After the more promising inbreds or clones have been selected on the basis of good general combining ability, it is necessary to identify the particular single, three-way or double cross that will produce the highest yields. A high seed yield potential is also important in a new variety so that the seeds can be sold at lower prices than other varieties. A tentative scheme for hybrid seed production by using inbred lines of male sterile or normal parents is proposed. At a breeding station, the seeds for male sterile F1(AB), maintainer S1(C-S1) and either maintainer or restorer S1s(D-S1, E-S1) are produced from the parental clones. At a seed increase agency, the seeds for male sterile F1(ABC) and either maintainer or restorer S2(D-S2) are produced. In the case that D-S2 seed production is difficult, maintainer or restorer F1(DE) should be produced from D-S1 x E-S1. These seeds are used for commercial seed production. Seeds of hybrid F1(ABCD) or hybrid F1(ABCDE) are for practical use. (Kaihara, S.)

  18. Achieving high-throughput State Machine Replication in multi-core systems

    Santos, Nuno; Schiper, André

    2011-01-01

    State machine replication is becoming an increasingly popular technique among online services to ensure fault-tolerance using commodity hardware. This has led to a renewed interest in its throughput, as these services have typically a large number of users. Recent work has shown how to improve the throughput of the replication protocol, using techniques like Ring-topologies, IP multicast, and rotating leaders. When deployed in modern fast networks, the resulting systems achieve unprecedented ...

  19. Exam High Schools and Academic Achievement: Evidence from New York City

    Will Dobbie; Roland G. Fryer, Jr.

    2011-01-01

    Publicly funded exam schools educate many of the world's most talented students. These schools typically contain higher achieving peers, more rigorous instruction, and additional resources compared to regular public schools. This paper uses a sharp discontinuity in the admissions process at three prominent exam schools in New York City to provide the first causal estimate of the impact of attending an exam school in the United States on longer term academic outcomes. Attending an exam school ...

  20. Junior High School Students’ Perception of Classroom Environment and Their English Achievement

    Rahmedia Alfi Rahmi; Chuzaimah Dahlan Diem

    2014-01-01

    Classroom environment is different from one school to another. This may lead to students’ achievement. This study was aimed at finding out whether the two variables were correlated positively by involving 378 students selected randomly from 55 schools in different sub-districts. The ‘What Is Happening In this Class (WIHIC) questionnaire’ and an English test were used to collect the data. The findings showed that: (1) there was a positive correlation between classroom environment and students’...

  1. Cadmium and chromium concentrations in six forage species irrigated with canal, sewage or mixed canal and sewage water

    Cadmium (Cd) and chromium (Cr) concentrations were investigated in six different forage species, i.e., Trifolium alexandrium, Cichorium intybus, Avena sativa, Medicago polymorpha, Brassica campestris and Medicago sativa, irrigated with canal, sewage or mixed canal and sewage water. The Cd levels of the forages irrigated with different water treatments in this study were greater than the tolerance level for grazing livestock reported in the literature. Thus, the Cd levels in the six plant species found in the current study showed high potential threat for livestock consuming these forages. Similarly, high levels of Cr in the six forages were observed with sewage water treatment only. However, in the present investigation, Cr concentration of forages was below the toxic level. Therefore, there was no threat of Cr toxicity for animals being reared on these forages. (author)

  2. From cradle to early grave: juvenile mortality in European shags Phalacrocorax aristotelis results from inadequate development of foraging proficiency.

    Daunt, F; Afanasyev, V; Adam, A; Croxall, J P; Wanless, S

    2007-08-22

    In most long-lived animal species, juveniles survive less well than adults. A potential mechanism is inferior foraging skills but longitudinal studies that follow the development of juvenile foraging are needed to test this. We used miniaturized activity loggers to record daily foraging times of juvenile and adult European shags Phalacrocorax aristotelis from fledging to the following spring. Juveniles became independent from their parents 40 days post-fledging. They compensated for poor foraging proficiency by foraging for approximately 3 h d(-1) longer than adults until constrained by day length in early November. Thereafter, juvenile foraging time tracked shortening day length up to the winter solstice, when foraging time of the two age classes converged and continued to track day length until early February. Few individuals died until midwinter and mortality peaked in January-February, with juvenile mortality (including some of the study birds) five times that of adults. In their last two weeks of life, juveniles showed a marked decline in foraging time consistent with individuals becoming moribund. Our results provide compelling evidence that juveniles compensate for poor foraging proficiency by increasing foraging time, a strategy that is limited by day length resulting in high winter mortality. PMID:17504733

  3. Rearing and foraging affects bumblebee (Bombus terrestris) gut microbiota.

    Newbold, Lindsay K; Oliver, Anna E; Cuthbertson, Leah; Walkington, Sarah E; Gweon, Hyun S; Heard, Matthew S; van der Gast, Christopher J

    2015-08-01

    Bumblebees are ecologically and economically important as pollinators of crop and wild plants, especially in temperate systems. Species, such as the buff-tailed bumblebee (Bombus terrestris), are reared commercially to pollinate high-value crops. Their highly specific gut microbiota, characterized by low diversity, may affect nutrition and immunity and are likely to be important for fitness and colony health. However, little is known about how environmental factors affect bacterial community structure. We analysed the gut microbiota from three groups of worker bumblebees (B. terrestris) from distinct colonies that varied in rearing and foraging characteristics: commercially reared with restricted foraging (RR); commercially reared with outside foraging (RF); and wild-caught workers (W). Contrary to previous studies, which indicate that bacterial communities are highly conserved across workers, we found that RF individuals had an intermediate community structure compared with RR and W types. Further, this was shaped by differences in the abundances of common operational taxonomic units (OTUs) and the diversity of rare OTUs present, which we propose results from an increase in the variety of carbohydrates obtained through foraging. PMID:25994560

  4. Evidence of trapline foraging in honeybees.

    Buatois, Alexis; Lihoreau, Mathieu

    2016-08-15

    Central-place foragers exploiting floral resources often use multi-destination routes (traplines) to maximise their foraging efficiency. Recent studies on bumblebees have showed how solitary foragers can learn traplines, minimising travel costs between multiple replenishing feeding locations. Here we demonstrate a similar routing strategy in the honeybee (Apis mellifera), a major pollinator known to recruit nestmates to discovered food resources. Individual honeybees trained to collect sucrose solution from four artificial flowers arranged within 10 m of the hive location developed repeatable visitation sequences both in the laboratory and in the field. A 10-fold increase of between-flower distances considerably intensified this routing behaviour, with bees establishing more stable and more efficient routes at larger spatial scales. In these advanced social insects, trapline foraging may complement cooperative foraging for exploiting food resources near the hive (where dance recruitment is not used) or when resources are not large enough to sustain multiple foragers at once. PMID:27307487

  5. Association between scores in high school, aptitude and achievement exams and early performance in health science college

    Al-Alwan Ibrahim

    2009-01-01

    Full Text Available This retrospective study was carried out to assess the correlation between admi-ssion criteria to health science colleges, namely, final high school grade and Saudi National Apti-tude and Achievement exams, and early academic performance in these colleges. The study inclu-ded 91 male students studying in the two-year pre-professional program at the King Saud bin Abdulaziz University for Health Sciences (KSAU-HS, Riyadh, Saudi Arabia. Records of these students were used to extract relevant information and their academic performance (based on the grade point average achieved at the end of the first semester of the pre-professional program, which were analytically studied. Pearson correlation coefficient was used to assess the associa-tions between the different scores. SPSS statistical program (version 12.0 was used for data ana-lyses. We found a strong correlation between the academic performance and the Achievement Exam, Aptitude Exam and high school final grade, with Pearson Correlation Coefficients of 0.96, 0.93, 0.87, respectively. The Saudi National Achievement Exam showed the most significant correla-tion. Our results indicate that academic performance showed good correlation with the admission criteria used, namely final high school grade, Saudi National Aptitude and Achievement Exams.

  6. Paternity Testing, a Poor Man’s Marker Assisted Breeding Strategy to Increase Selection Gains in Outbred Forage Species

    Many methods to incorporate molecular markers into breeding programs have been proposed. Most existing marker assisted selection strategies use selection based on molecular marker linkage to achieve selection gains. Such strategies are often prohibitively expensive in forage breeding (Riday, 2007)...

  7. Foraging: an ecology model of consumer behaviour?

    Wells, V.K.

    2012-01-01

    Foraging theory is a well established set of models and ideas in ecology, anthropology and behavioural psychology. Two areas of research, the behavioural ecology of consumption and information foraging, have made strides in the application of foraging theories in relation to consumption and related behaviours. These focus on online situations and restrictions in methodologies utilized allows application to only a small range of marketing problems. This paper broadens the application of these ...

  8. Following Different Pathways: Social Integration, Achievement, and the Transition to High School

    LANGENKAMP, AMY G.

    2009-01-01

    This study expands research on an academic and social turning point for adolescents, the transition to high school, by analyzing how students’ level of social integration into school can affect high school academic performance. Using nationally representative data, three different pathways emerged as students transition to high school, characterized by varying amounts of disruption and opportunity for new social relationships upon entering high school. Findings suggest that elements of middle...

  9. Inquiry-Based Laboratory Activities in Electrochemistry: High School Students' Achievements and Attitudes

    Sesen, Burcin Acar; Tarhan, Leman

    2013-01-01

    This study aimed to investigate the effects of inquiry-based laboratory activities on high school students' understanding of electrochemistry and attitudes towards chemistry and laboratory work. The participants were 62 high school students (average age 17 years) in an urban public high school in Turkey. Students were assigned to experimental (N =…

  10. Safety as high and as harmonized as reasonably achievable: Nuclear regulators facing globalization

    The use of nuclear energy and ionizing radiation is being extensively scrutinized once again in light of the present debate on its role in sustainable development and on global security problems. Nuclear power is an important feature of today's energy supply. Commercial nuclear generation is a mature, established technology, having accumulated over 40 years of successful operation. Yet nuclear power raises passions as do few other energy issues. Within countries and among them, both support and opposition are strong. Loyola de Palacio, the European Union Commissioner responsible for energy and transport, summed up the dilemma very succinctly: Either we shut down the nuclear sector and give up on Kyoto, or we do not shut down the nuclear sector and we respect Kyoto. It is as simple as that: sometimes you have to put it crudely so that people understand. What is the role of nuclear regulators in this environment? The primary objective of government intervention into nuclear business is to allow humankind to maximize the benefits and minimize the risks emanating from nuclear sciences and their applications. Because both the nuclear power industry and the societal context within which it is regulated are dynamic, regulators must continuously assess their approaches to regulation to best achieve their regulatory mandate. This includes adjusting the boundaries of activity between the plant and the regulator. That is, working out the practical approaches that allow the power reactor operator/owner to achieve and maintain safety while allowing the regulatory body to assure itself and the public that appropriate levels of safety are achieved and maintained

  11. IDENTITY AND TEMPORAL PERSPECTIVE OF ADOLESCENTS WITH HIGH ACHIEVEMENTS IN SCHOOL

    Denitsa Alipieva

    2015-12-01

    Full Text Available The current article is an empirical approach reviewing the theories for the factors for formation of identity and self-conception in the adolescent. Under the theories for internal attribution and temporal perspective the study was conducted with teenagers between 11 and 18 years with different achievements. The aim is to show the relevance between the subjective affective involving and success in academic activity and realistic self-esteem that could enhance the abilities of students to create adequate plans and goals for future and mature self-conception

  12. Boa constrictor (Boa constrictor): foraging behavior

    Sorrell, G.G.; Boback, M.S.; Reed, R.N.; Green, S.; Montgomery, Chad E.; DeSouza, L.S.; Chiaraviglio, M.

    2011-01-01

    Boa constrictor is often referred to as a sit-and-wait or ambush forager that chooses locations to maximize the likelihood of prey encounters (Greene 1983. In Janzen [ed.], Costa Rica Natural History, pp. 380-382. Univ. Chicago Press, Illinois). However, as more is learned about the natural history of snakes in general, the dichotomy between active versus ambush foraging is becoming blurred. Herein, we describe an instance of diurnal active foraging by a B. constrictor, illustrating that this species exhibits a range of foraging behaviors.

  13. U.S. Dairy Forage Research Center

    Federal Laboratory Consortium — Vision: Leading the world in integrated dairy forage systems research. Mission: Providing dairy industry solutions for food security, environmental sustainability,...

  14. U.S. DAIRY FORAGE RESEARCH CENTER

    Federal Laboratory Consortium — Vision: Leading the world in integrated dairy forage systems research. Mission: Providing dairy industry solutions for food security, environmental sustainability,...

  15. The effects of a science intervention program on the attitudes and achievement of high school girls in science

    Steakley, Carrie Capers

    This study investigated the effects of a high school science intervention program that included hands-on activities, science-related career information and exposure, and real-world experiences on girls' attitudes and achievement in science. Eighty-four girls, 44 ninth-graders and 40 tenth-graders, and 105 parents participated in the study. Survey data was collected to assess the girls' attitudes toward science in seven distinct areas: social implications of science, normality of scientists, attitude toward scientific inquiry, adoption of scientific attitudes, enjoyment of science lessons, leisure interest in science, and career interest in science. Additional questionnaires were used to determine the extent of the girls' participation in sports and the attitudes of their parents toward science. The girls' cumulative science semester grade point averages since the seventh grade were used to assess academic science achievement. This study found no evidence that participation in the program improved the girls' attitudes or achievement in science. Parent attitudes and years of participation in sports were not accurate predictors of science achievement. Additionally, no significant relationship was detected between the girls' and their parents' perceptions of science. However, the study did suggest that extended participation in sports may positively affect science achievement for girls. This study holds implications for educational stakeholders who seek to implement intervention methods and programs that may improve student attitudes and achievement in science and attract more youth to future science-related careers.

  16. Individual honey bee (Apis cerana) foragers adjust their fuel load to match variability in forage reward

    Tan, Ken; Latty, Tanya; Dong, Shihao; Liu, Xiwen; Wang, Chao; Oldroyd, Benjamin P.

    2015-01-01

    Animals may adjust their behavior according to their perception of risk. Here we show that free-flying honey bee (Apis cerana) foragers mitigate the risk of starvation in the field when foraging on a food source that offers variable rewards by carrying more ‘fuel’ food on their outward journey. We trained foragers to a feeder located 1.2 km from each of four colonies. On average foragers carried 12.7% greater volume of fuel, equivalent to 30.2% more glucose when foraging on a variable source (a random sequence of 0.5, 1.5 and 2.5 M sucrose solution, average sucrose content 1.5 M) than when forging on a consistent source (constant 1.5 M sucrose solution). Our findings complement an earlier study that showed that foragers decrease their fuel load as they become more familiar with a foraging place. We suggest that honey bee foragers are risk sensitive, and carry more fuel to minimize the risk of starvation in the field when a foraging trip is perceived as being risky, either because the forager is unfamiliar with the foraging site, or because the forage available at a familiar site offers variable rewards. PMID:26549746

  17. High-School Students' Need for Cognition, Self-Control Capacity, and School Achievement: Testing a Mediation Hypothesis

    Bertrams, Alex; Dickhauser, Oliver

    2009-01-01

    In the present article, we examine the hypothesis that high-school students' motivation to engage in cognitive endeavors (i.e., their need for cognition; NFC) is positively related to their dispositional self-control capacity. Furthermore, we test the prediction that the relation between NFC and school achievement is mediated by self-control…

  18. Mathematics: Self-Efficacy, Identity, and Achievement among African American Males from the High School Longitudinal Study

    Briggs, Calvin

    2014-01-01

    The purpose of this study was to determine if a relationship existed between mathematics self-efficacy and mathematics identity to mathematics achievement among African American males from High School Longitudinal Study of 2009 (HSLS:09). Subsequently, the extent to which mathematics self-efficacy and mathematics identity accounted for low and…

  19. The Perceptions of Principals and Teachers Regarding Mental Health Providers' Impact on Student Achievement in High Poverty Schools

    Perry, Teresa

    2012-01-01

    This study examined the perceptions of principals and teachers regarding mental health provider's impact on student achievement and behavior in high poverty schools using descriptive statistics, t-test, and two-way ANOVA. Respondents in this study shared similar views concerning principal and teacher satisfaction and levels of support for the…

  20. Black High School Students' Participation in School-Sponsored Sports Activities: Effects on School Engagement and Achievement.

    Jordan, Will J.

    1999-01-01

    Examined the effects of sports participation on African American high school students' school engagement, academic achievement, and self-evaluation. Data from the National Educational Longitudinal Study of 1998 indicated that sports participation improved African American students' school engagement and academic self-confidence. There was a…

  1. The Relationship between School Culture and Student Achievement: Perceptions of Georgia Suburban and Urban High School Administrators

    Tucker, Treva L.

    2011-01-01

    The purpose of this quantitative research study was to determine the relative impact school culture has on student achievement (specifically AYP status, dropout rates and graduation rates) in select urban and suburban Georgia high schools. To examine this relationship, the researcher reviewed data collected from the School Culture Survey (SCS)…

  2. Differences between High and Low Academic Achieving University Students in Learning and Study Strategies: A Further Investigation

    Yip, Michael C. W.

    2009-01-01

    Following up on the general framework of the research study of Yip (2007), this article sets out a similar research question, investigating the differences between high and low academic achieving Hong Kong university students based on their different learning and study strategies. In this study, we recruited 100 university students who pursued…

  3. Self-Regulated Learning and a Sense of Achievement in MOOCs among High School Science and Technology Students

    Cohen, Lizi; Magen-Nagar, Noga

    2016-01-01

    This study, conducted in Israel, examined how learning strategies and motivational orientations contributed to high school students' sense of achievement in a massive open online course. The objective was to integrate an innovative teaching-learning strategy into the educational system that is based on online learning for students in subjects that…

  4. The Effect of Poverty on the Achievement of Urban African American Male Students Successfully Completing High School

    Welch, Amy L.

    2013-01-01

    The purpose of this study was to determine the impact of poverty on the achievement of African American male high school students attending the same large Midwest urban school district. Cumulative grade point average (GPA) at the tenth grade level were compared to the level of poverty provided through census data of African American male tenth…

  5. The Effect of Blended Learning Model on High School Students' Biology Achievement and on Their Attitudes towards the Internet

    Yapici, I.Umit; Akbayin, Hasan

    2012-01-01

    The present study aims to determine the effect of the blended learning model on high school students' biology achievement and on their attitudes towards the Internet. Among the experimental models, the pretest-posttest control group model was used in the study. The study was carried out with 107 students (47 of whom were in the experimental group,…

  6. Challenge and Success: A Qualitative Study of the Career Development of Highly Achieving Women With Physical and Sensory Disabilities

    Noonan, Brigid M.; Gallor, Susanna M.; Hensler-McGinnis, Nancy F.; Fassinger, Ruth E.; Wang, Shihwe; Goodman, Jennifer

    2004-01-01

    This qualitative study examined the career development experiences of 17 highly achieving women with physical and sensory disabilities. Interviews were conducted and data were analyzed using modified grounded theory strategies (A. L. Strauss & J. Corbin, 1998). The emergent theoretical model was conceptualized as a system of influences organized…

  7. Unpacking High and Low Efficacy Teachers' Task Analysis and Competence Assessment in Teaching Low-Achieving Students in Secondary Schools

    Wang, Li-Yi; Jen-Yi, Li; Tan, Liang-See; Tan, Irene; Lim, Xue-Fang; Wu, Bing Sheng

    2016-01-01

    This study adopted a pragmatic qualitative research design to unpack high and low efficacy teachers' task analysis and competence assessment in the context of teaching low-achieving students. Nine secondary school English and Science teachers were recruited and interviewed. Results of thematic analysis show that helping students perform well in…

  8. High-Achieving Black Students, Biculturalism, and Out-of-School STEM Learning Experiences: Exploring Some Unintended Consequences

    McGee, Ebony O.

    2013-01-01

    In this article, the author discusses the complex challenges of high-achieving Black students who are successful in becoming immersed in predominately White STEM (science, technology, engineering, and mathematics) spaces and how such immersion can exacerbate their experiences of racial stereotyping and other forms of racial bias. The author…

  9. An Exploration of the Psychosocial Characteristics of High Achieving Students and Identified Gifted Students: Implications for Practice

    Ritchotte, Jennifer A.; Suhr, Diana; Alfurayh, Naif F.; Graefe, Amy K.

    2016-01-01

    High achieving students or "bright children" are often denied access to gifted services because they do not meet "gifted" criteria. Although psychosocial factors play an integral role in academic success, and can be useful in providing a clearer picture of student need, they are seldom considered in the decision to identify a…

  10. Predicting High School Graduation for Latino Males Using Expectancy Value Theory of Motivation and Tenth Grade Reading Achievement Scores

    Knape, Erin Oakley

    2010-01-01

    National education data indicate that young men of color and students living in poverty are not experiencing the same academic success as their female, White, or higher socioeconomic status peers, as evidenced by low reading achievement levels and high dropout rates. Of particular concern is the underachievement of Latino males, who currently have…

  11. Public, Catholic Single-Sex, and Catholic Coeducational High Schools: Their Effects on Achievement, Affect, and Behaviors.

    Marsh, Herbert W.

    1991-01-01

    Using data from the High School and Beyond survey, compares junior and senior year performance and other variables in Catholic single sex, Catholic coed, and public schools. Finds Catholic school students are urged to take more academically demanding courses; this accounts for public/Catholic differences in achievement and university attendance.…

  12. Practice Brief: Assessing Compensatory Strategies and Motivational Factors in High-Achieving Postsecondary Students with Attention Deficit/Hyperactivity Disorder

    Schaffer, Gary

    2013-01-01

    Research speculates that high-achieving college students with attention deficit/hyperactivity disorder (ADHD) may demonstrate a set of compensatory strategies and experience areas of difficulty and motivational factors that differ from the general ADHD populace. This Practice Brief used informal surveys with seven undergraduates with ADHD who had…

  13. Examining the Predictive Power of Autonomy and Self-Evaluation on High School Students' Language Achievement

    Yuksel, Ismail; Toker, Yalcin

    2013-01-01

    This study aims to determine language learners' autonomy, self-evaluation levels and to examine the predictive power of these two variables on language achievement. The study was designed as mixed method design and was conducted with 108 high school students. Data were collected through an autonomy scale, a self-evaluation scale, schools…

  14. High school students' science academic achievement: The effect of the Lemov positive framing trust-building technique

    Gigliette, Linda Marie

    The purpose of this research was to investigate the effect of a trust-building technique called "positive-framing" (Lemov, 2010, p. 204) on the level of student-teacher trust and students' science academic achievement. The existing literature was reviewed under the constructs of trust, types of trust, trust-building strategies, and student academic achievement. The identified problem is a lack of research into the effect of trust from the high school student perspective and the effect of trust on student academic achievement in science. In addition, there is no empirical evidence to support the effectiveness of the "positive-framing" (Lemov, 2010, p. 204) trust-building intervention. The study involved a volunteer, convenience sample of 9th-grade science students at one high school in Northern California (N=240). The study employed a quasi-experimental, pretest, posttest non-equivalent control group design to examine the level of student trust in the teacher, using the "Student trust in faculty scale" (Forsyth, Adams, & Hoy, 2011, p. 180), and the students' academic achievement, according to the Integrated Process Skills Test II (Okey, Wise, & Burns, 1982). The independent variable was the "positive-framing" (Lemov, 2010, p. 204) trust-building intervention; the two dependent variables were the level of student-teacher trust and student academic achievement. The composite data from the "Student trust in faculty scale" and the academic achievement test were evaluated by a multivariate analysis of covariance (MANCOVA). Results of this study indicated that the null hypothesis was accepted. The "positive-framing" (Lemov, 2010, p. 204) trust-building intervention did not have a significant effect on either the student-teacher trust level or academic achievement in science.

  15. The Relationship between Motivations and Self-Learning and the English Language Achievement in Secondary High School Students

    Hadriana Hadriana

    2013-08-01

    Full Text Available This study aims to determine the level of motivation and relationship of intrinsic and extrinsic motivations and self-learning concerning students’ achievement in the English language, in relevance with their determination and the use of English to derive knowledge and as a medium of communication. A total of 120 secondary high school students in Pekanbaru Riau, Indonesia were randomly chosen as sample to evaluate and determine the influence of internal and external factors, as well as self-learning in mastering the English Language. A set of questionnaire was used in this study to assess the level of students’ motivation and self-learning and its relationship with their achievement. A test was used to measure the level of English proficiency. Pearson correlation and descriptive analysis were used to analyze the findings by using SPSS version 19.0. The findings showed a medium high level of intrinsic motivation, extrinsic motivation and self-learning, whereas students’ achievement was simply at the medium low level. The findings show that there is a less significant relationship between extrinsic motivation and the English Language achievement among students, however there is no significant relationship between intrinsic motivation and self-learning with the achievement. The study also stressed on the importance of providing a supportive learning environment to inspire and encourage students’ interest to form a culture of learning English Language rather than independent learning and intrinsic motivation.

  16. Shedding light on light: benefits of anthropogenic illumination to a nocturnally foraging shorebird.

    Dwyer, Ross G; Bearhop, Stuart; Campbell, Hamish A; Bryant, David M

    2013-03-01

    Intertidal habitats provide important feeding areas for migratory shorebirds. Anthropogenic developments along coasts can increase ambient light levels at night across adjacent inter-tidal zones. Here, we report the effects of elevated nocturnal light levels upon the foraging strategy of a migratory shorebird (common redshank Tringa totanus) overwintering on an industrialised estuary in Northern Europe. To monitor behaviour across the full intertidal area, individuals were located by day and night using VHF transmitters, and foraging behaviour was inferred from inbuilt posture sensors. Natural light was scored using moon-phase and cloud cover information and nocturnal artificial light levels were obtained using geo-referenced DMSP/OLS night-time satellite imagery at a 1-km resolution. Under high illumination levels, the commonest and apparently preferred foraging behaviour was sight-based. Conversely, birds feeding in areas with low levels of artificial light had an elevated foraging time and fed by touch, but switched to visual rather than tactile foraging behaviour on bright moonlit nights in the absence of cloud cover. Individuals occupying areas which were illuminated continuously by lighting from a large petrochemical complex invariably exhibited a visually based foraging behaviour independently of lunar phase and cloud cover. We show that ambient light levels affect the timing and distribution of foraging opportunities for redshank. We argue that light emitted from an industrial complex improved nocturnal visibility. This allowed sight-based foraging in place of tactile foraging, implying both a preference for sight-feeding and enhanced night-time foraging opportunities under these conditions. The study highlights the value of integrating remotely sensed data and telemetry techniques to assess the effect of anthropogenic change upon nocturnal behaviour and habitat use. PMID:23190422

  17. Contrasting Foraging Patterns: Testing Resource-Concentration and Dilution Effects with Pollinators and Seed Predators

    Alexandria Wenninger

    2016-06-01

    Full Text Available Resource concentration effects occur when high resource density patches attract and support more foragers than low density patches. In contrast, resource dilution effects can occur if high density patches support fewer consumers. In this study, we examined the foraging rates of pollinators and seed predators on two perennial plant species (Rudbeckia triloba and Verbena stricta as functions of resource density. Specifically, we examined whether resource-dense patches (densities of flower and seeds on individual plants resulted in greater visitation and seed removal rates, respectively. We also examined whether foraging rates were context-dependent by conducting the study in two sites that varied in resource densities. For pollinators, we found negative relationships between the density of flowers per plant and visitation rates, suggesting dilution effects. For seed predators, we found positive relationships consistent with concentration effects. Saturation effects and differences in foraging behaviors might explain the opposite relationships; most of the seed predators were ants (recruitment-based foragers, and pollinators were mostly solitary foragers. We also found that foraging rates were site-dependent, possibly due to site-level differences in resource abundance and consumer densities. These results suggest that these two plant species may benefit from producing as many flowers as possible, given high levels of pollination and low seed predation.

  18. Contrasting Foraging Patterns: Testing Resource-Concentration and Dilution Effects with Pollinators and Seed Predators.

    Wenninger, Alexandria; Kim, Tania N; Spiesman, Brian J; Gratton, Claudio

    2016-01-01

    Resource concentration effects occur when high resource density patches attract and support more foragers than low density patches. In contrast, resource dilution effects can occur if high density patches support fewer consumers. In this study, we examined the foraging rates of pollinators and seed predators on two perennial plant species (Rudbeckia triloba and Verbena stricta) as functions of resource density. Specifically, we examined whether resource-dense patches (densities of flower and seeds on individual plants) resulted in greater visitation and seed removal rates, respectively. We also examined whether foraging rates were context-dependent by conducting the study in two sites that varied in resource densities. For pollinators, we found negative relationships between the density of flowers per plant and visitation rates, suggesting dilution effects. For seed predators, we found positive relationships consistent with concentration effects. Saturation effects and differences in foraging behaviors might explain the opposite relationships; most of the seed predators were ants (recruitment-based foragers), and pollinators were mostly solitary foragers. We also found that foraging rates were site-dependent, possibly due to site-level differences in resource abundance and consumer densities. These results suggest that these two plant species may benefit from producing as many flowers as possible, given high levels of pollination and low seed predation. PMID:27271673

  19. Gender differences in Korean high school students’ science achievements and attitudes towards science in three different school settings

    EunJin Bang; Dale R. Baker

    2013-01-01

    This study analysed the effect of high schools' gender organization on Korean tenth-grade students’ science achievements, and their attitudes towards science. The high schools involved included an all-male institution, an all-female institution, and a co-educational institution. Three schools, three principals, three science teachers, and 302 tenthgrade students from their respective school types responded to an initial survey, and eleven academically outstanding students were subsequently in...

  20. Fuel Element Designs for Achieving High Burnups in 220 MW(e) Indian PHWRs

    Presently 19-element natural uranium fuel bundles are used in 220 MW(e) Indian PHWRs. The core average design discharge burnup for these bundles is 7000 MW·d/Te U and maximum burnup for assembly goes upto of 15 000 MWD/Te U. Use of fuel materials like MOX, Thorium, slightly enriched uranium etc in place of natural uranium in 19-element fuel bundles, in 220 MW(e) PHWRs is being investigated to achieve higher burnups. The maximum burnup investigated with these bundles is 30 000 MW·d/Te U. In PHWR fuel elements no plenum space is available and the cladding is of collapsible type. Studies have been carried out for different fuel element target burnups with different alternative concepts. Modification in pellet shape and pellet parameters are considered. These studies for the PHWR fuel elements/assemblies have been elaborated in this paper. (author)

  1. Teachers' Awareness of Cultural Diversity and Academic Achievement in Ninth Grade Academies and Senior High Schools

    Whipps-Johnson, Jamellah Renee

    2016-01-01

    High school graduation rates are higher than they have ever been in 40 years, but disparities continue to exist for students of color and students from poverty when compared to their counterparts. High school reform efforts like creating small learning communities are promising, but small schools alone do not improve student outcomes.…

  2. The Relationships among Reported Strategy Use, Metacognitive Awareness, and Reading Achievement of High School Students

    Hong-Nam, Kay; Leavell, Alexandra G.; Maher, Sheila

    2014-01-01

    The metacognitive awareness and reading strategy use of high school students enrolled in two high schools were investigated. The correlations between reading scores and strategy use were examined as well as the variation in strategy use by self-rated reading proficiency and academic grades. The factor analysis revealed four factors on the…

  3. The Effects of Two Scheduling Formats on Student Achievement in a Suburban High School Setting

    Jackson, Kenyada Morton

    2013-01-01

    Limited studies have been conducted on the relationship between scheduling formats and academic performance of high school students. At the target high school, students underperform on standardized tests in English language arts (ELA) and math. The purpose of this causal comparative quantitative study was to compare the means of ELA and math test…

  4. Experimental evidence for cryptic interference among socially foraging shorebirds

    Bijleveld, Allert Imre; Folmer, Eelke Olov; Piersma, Theunis

    2012-01-01

    Foraging rate and the distribution of foragers depend on prey distribution in conjunction with interindividual interactions. Generalized functional response models predict intake rates and spatial distributions of foragers on the basis of resource distribution and interference competition. The adequ

  5. The roles of sex, mass and individual specialisation in partitioning foraging-depth niches of a pursuit-diving predator.

    Ratcliffe, Norman; Takahashi, Akinori; O'Sullivan, Claire; Adlard, Stacey; Trathan, Philip N; Harris, Michael P; Wanless, Sarah

    2013-01-01

    Intra-specific foraging niche partitioning can arise due to gender differences or individual specialisation in behaviour or prey selection. These may in turn be related to sexual size dimorphism or individual variation in body size through allometry. These variables are often inter-related and challenging to separate statistically. We present a case study in which the effects of sex, body mass and individual specialisation on the dive depths of the South Georgia shag on Bird Island, South Georgia are investigated simultaneously using a linear mixed model. The nested random effects of trip within individual explained a highly significant amount of the variance. The effects of sex and body mass were both significant independently but could not be separated statistically owing to them being strongly interrelated. Variance components analysis revealed that 45.5% of the variation occurred among individuals, 22.6% among trips and 31.8% among Dives, while R(2) approximations showed gender explained 31.4% and body mass 55.9% of the variation among individuals. Male dive depths were more variable than those of females at the levels of individual, trip and dive. The effect of body mass on individual dive depths was only marginally significant within sexes. The percentage of individual variation in dive depths explained by mass was trivial in males (0.8%) but substantial in females (24.1%), suggesting that differences in dive depths among males was largely due to them adopting different behavioural strategies whereas in females allometry played an additional role. Niche partitioning in the study population therefore appears to be achieved through the interactive effects of individual specialisation and gender upon vertical foraging patch selection, and has the potential to interact in complex ways with other axes of the niche hypervolume such as foraging locations, timing of foraging and diet. PMID:24205368

  6. The roles of sex, mass and individual specialisation in partitioning foraging-depth niches of a pursuit-diving predator.

    Norman Ratcliffe

    Full Text Available Intra-specific foraging niche partitioning can arise due to gender differences or individual specialisation in behaviour or prey selection. These may in turn be related to sexual size dimorphism or individual variation in body size through allometry. These variables are often inter-related and challenging to separate statistically. We present a case study in which the effects of sex, body mass and individual specialisation on the dive depths of the South Georgia shag on Bird Island, South Georgia are investigated simultaneously using a linear mixed model. The nested random effects of trip within individual explained a highly significant amount of the variance. The effects of sex and body mass were both significant independently but could not be separated statistically owing to them being strongly interrelated. Variance components analysis revealed that 45.5% of the variation occurred among individuals, 22.6% among trips and 31.8% among Dives, while R(2 approximations showed gender explained 31.4% and body mass 55.9% of the variation among individuals. Male dive depths were more variable than those of females at the levels of individual, trip and dive. The effect of body mass on individual dive depths was only marginally significant within sexes. The percentage of individual variation in dive depths explained by mass was trivial in males (0.8% but substantial in females (24.1%, suggesting that differences in dive depths among males was largely due to them adopting different behavioural strategies whereas in females allometry played an additional role. Niche partitioning in the study population therefore appears to be achieved through the interactive effects of individual specialisation and gender upon vertical foraging patch selection, and has the potential to interact in complex ways with other axes of the niche hypervolume such as foraging locations, timing of foraging and diet.

  7. Combining enhanced biomass density with reduced lignin level for improved forage quality.

    Gallego-Giraldo, Lina; Shadle, Gail; Shen, Hui; Barros-Rios, Jaime; Fresquet Corrales, Sandra; Wang, Huanzhong; Dixon, Richard A

    2016-03-01

    To generate a forage crop with increased biomass density that retains forage quality, we have genetically transformed lines of alfalfa (Medicago sativa L.) expressing antisense constructs targeting two different lignin pathway biosynthetic genes with a construct for down-regulation of a WRKY family transcription factor that acts as a repressor of secondary cell wall formation in pith tissues. Plants with low-level expression of the WRKY dominant repressor construct produced lignified cell walls in pith tissues and exhibited enhanced biomass and biomass density, with an increase in total sugars in the cell wall fraction; however, lines with high expression of the WRKY dominant repressor construct exhibited a very different phenotype, with loss of interfascicular fibres associated with repression of the NST1 transcription factor. This latter phenotype was not observed in transgenic lines in which the WRKY transcription factor was down-regulated by RNA interference. Enhanced and/or ectopic deposition of secondary cell walls was also seen in corn and switchgrass expressing WRKY dominant repressor constructs, with enhanced biomass in corn but reduced biomass in switchgrass. Neutral detergent fibre digestibility was not impacted by WRKY expression in corn. Cell walls from WRKY-DR-expressing alfalfa plants with enhanced secondary cell wall formation exhibited increased sugar release efficiency, and WRKY dominant repressor expression further increased sugar release in alfalfa down-regulated in the COMT, but not the HCT, genes of lignin biosynthesis. These results suggest that significant enhancements in forage biomass and quality can be achieved through engineering WRKY transcription factors in both monocots and dicots. PMID:26190611

  8. Grazing season and forage type influence goat milk composition and rennet coagulation properties.

    Inglingstad, R A; Steinshamn, H; Dagnachew, B S; Valenti, B; Criscione, A; Rukke, E O; Devold, T G; Skeie, S B; Vegarud, G E

    2014-01-01

    Two different types of pasture (cultivated and rangeland) and 2 different hay qualities (high and low quality) were examined for their effects on goat milk composition and rennet coagulation properties. Furthermore, the effect of dietary treatments in both the early and late grazing season was studied. As lactation stage is known to influence milk composition, the goats in the early and late grazing season were in the same lactation stage at the start of the experiment. The milk composition was influenced both by dietary treatment and season. Milk from goats on pasture was superior to those on hay by containing a higher content of protein and casein, and the goats on cultivated pasture had the highest milk yield. Casein composition was significantly influenced by forage treatment. Goats grazing on cultivated pasture had higher contents of αs1-casein and also of κ-casein compared with the other treatments, whereas goats grazing on rangeland had the highest content of β-casein. Factors such as milk yield, casein micelle size, αs2-casein, and calcium content were reduced in late compared with early season. More favorable rennet coagulation properties were achieved in milk from the early grazing season, with shorter firming time and higher curd firmness compared with milk from the late grazing season, but the firming time and curd firmness were not prominently influenced by forage treatment. The content of αs2-casein and calcium in the milk affected the firming time and the curd firmness positively. The influence of season and forage treatment on especially milk yield, casein content, and rennet coagulation properties is of economic importance for both the dairy industry and goat milk farmers. PMID:24704223

  9. Following a foraging fish-finder: diel habitat use of Blainville's beaked whales revealed by echolocation.

    Patricia Arranz

    Full Text Available Simultaneous high resolution sampling of predator behavior and habitat characteristics is often difficult to achieve despite its importance in understanding the foraging decisions and habitat use of predators. Here we tap into the biosonar system of Blainville's beaked whales, Mesoplodon densirostris, using sound and orientation recording tags to uncover prey-finding cues available to echolocating predators in the deep-sea. Echolocation sounds indicate where whales search and encounter prey, as well as the altitude of whales above the sea-floor and the density of organisms around them, providing a link between foraging activity and the bio-physical environment. Tagged whales (n = 9 hunted exclusively at depth, investing most of their search time either in the lower part of the deep scattering layer (DSL or near the sea-floor with little diel change. At least 43% (420/974 of recorded prey-capture attempts were performed within the benthic boundary layer despite a wide range of dive depths, and many dives included both meso- and bentho-pelagic foraging. Blainville's beaked whales only initiate searching when already deep in the descent and encounter prey suitable for capture within 2 min of the start of echolocation, suggesting that these whales are accessing prey in reliable vertical strata. Moreover, these prey resources are sufficiently dense to feed the animals in what is effectively four hours of hunting per day enabling a strategy in which long dives to exploit numerous deep-prey with low nutritional value require protracted recovery periods (average 1.5 h between dives. This apparent searching efficiency maybe aided by inhabiting steep undersea slopes with access to both the DSL and the sea-floor over small spatial scales. Aggregations of prey in these biotopes are located using biosonar-derived landmarks and represent stable and abundant resources for Blainville's beaked whales in the otherwise food-limited deep-ocean.

  10. An examination of the saturation microstructures achieved in ultrafine-grained metals processed by high-pressure torsion

    Shima Sabbaghianrad

    2014-10-01

    Full Text Available Experiments were conducted on two commercial alloys, a Cu–0.1%Zr alloy and an Al-7075 aluminum alloy, to investigate the significance of the saturation microstructure which is achieved after processing by high-pressure torsion (HPT. Samples were processed by HPT and also by a combination of equal-channel angular pressing (ECAP followed by HPT. The results show that the saturation conditions are dependent upon the grain size in the material immediately prior to the HPT processing. Additional grain refinement may be achieved in HPT by initially processing the material to produce an ultrafine-grain size before conducting the processing by HPT.

  11. Tropical forage meals: An alternative for sustainable monogastric species production

    digestibility studies in vitro. Growing guinea pig Macabea) of 700 gr were used for digestibility and morphophysiological and performances studies. Tropical forage meals bromatological composition does not show their nutritional potential value that is limited by its fibrous fraction and secondary metabolites that could decrease digestive utilisation in monogastric species. It was shown that determination of physico-chemical characterization (solubility, volume, water holding capacity, cationic interchange capacity, acid and basic buffer capacity are necessary for nutritive evaluation of fibrous feed for monogastric species. Forage meals spectra analysis confirmed the similarity between FDN structure and chemical composition. This could contribute to the utilisation and manipulation of these sources in order to formulate monogastric species rations. Inclusions levels of tropical forage meals sere related to species digestive characteristics as well as with sensitivity to secondary metabolites present. Among forage legumes, dolicho was the most promising species due to its results in digestive utilisation of fibrous components and in the morphopysiology of gastrointestinal tract of poultry, swine and rabbits. It was shown that the complete replacement of alfalfa forage meal by mulberry in rabbits was possible taking into account its low lignin content, high digestive utilisation of fibrous components and its similar nutrient value. It is possible to replace until 30% of alfalfa meal by mulberry, trichantera and eritrina in concentrate for growing guinea pig without affecting nutrient consumption, morphophysiological indices, nor productive performances (experimental scale) and to obtain improvements in production costs. The application of these knowledge will allow making decisions and taking choices in the formulation of diets based in forage meals for non ruminant species. These results proportionate improvements in production performances with sustainable conditions for small

  12. 黑龙江省垦区西北部高寒地区优质牧草引种试验%Introduction Test of Forages of High Quality in Cold Area in Northwest Part of Heilongjiang Reclamation Area

    范圣华; 孙伯臣; 邱继兰; 阚文亮; 荣占华

    2009-01-01

    对来源不同的22份优质牧草材料通过4年(2004~2007年)的试验进行筛选,结果表明:草原2号苜蓿、肇东苜蓿、龙牧801苜蓿、农菁1号苜蓿、草原1.号苜蓿、敖汉苜蓿、公农1号苜蓿、羊草、鹅观草、冰草等牧草能够在黑龙江垦区西北部高寒地区安全越冬,产量性状、抗病性等都优于其它品种.%22 high-quality forage materials from different parts were screened for four years (2004~ 2007), the results showed that: alfalfa "Caoyuan No. 2",alfalfa "Zhaodong", alfalfa "Longmu 801", alfal- fa "Nongjing No. 1", alfalfa "Caoyuan No. 1", alfalfa "Aohan", alfalfa "Gongnong No. 1", Leymus chinesis, Roegneria kamogi and wheatgrass can over winter safely, they were superior to other varieties in yield and diseases resistance.

  13. Achieving High Performance Distributed System: Using Grid, Cluster and Cloud Computing

    Sunil Kr Singh; Kavneet Kaur

    2015-01-01

    To increase the efficiency of any task, we require a system that would provide high performance along with flexibilities and cost efficiencies for user. Distributed computing, as we are all aware, has become very popular over the past decade. Distributed computing has three major types, namely, cluster, grid and cloud. In order to develop a high performance distributed system, we need to utilize all the above mentioned three types of computing. In this paper, we shall first have a...

  14. Environmental conditions and intraspecific interference: unexpected effects of turbidity on pike (Esox lucius) foraging

    Nilsson, P.A.; Jacobsen, Lene; Berg, Søren;

    2009-01-01

    on pike foraging alone or among conspecifics in different levels of water turbidity, we expected high turbidity to decrease the perceived risk of intraspecific interactions among pike, and thereby decrease the strength of interference, as turbidity would decrease the visual contact between...... individuals and act as a refuge from behavioural interactions. The results show that this is not the case, but suggest that interference is induced instead of reduced in high turbidity. Per capita foraging rates do not differ between pike foraging alone or in groups in our clear and moderately turbid...... treatments, indicating no effect of interference. As high turbidity enhances prey consumption for pike individuals foraging alone, but does not have this effect for pike in groups, high turbidity induces the relative interference effect. We suggest that future evaluations of the stabilizing effects of...

  15. Individual honey bee (Apis cerana) foragers adjust their fuel load to match variability in forage reward

    Ken Tan; Tanya Latty; Shihao Dong; Xiwen Liu; Chao Wang; Oldroyd, Benjamin P.

    2015-01-01

    Animals may adjust their behavior according to their perception of risk. Here we show that free-flying honey bee (Apis cerana) foragers mitigate the risk of starvation in the field when foraging on a food source that offers variable rewards by carrying more ‘fuel’ food on their outward journey. We trained foragers to a feeder located 1.2 km from each of four colonies. On average foragers carried 12.7% greater volume of fuel, equivalent to 30.2% more glucose when foraging on a variable source ...

  16. A comprehensive approach to decipher biological computation to achieve next generation high-performance exascale computing.

    James, Conrad D.; Schiess, Adrian B.; Howell, Jamie; Baca, Micheal J.; Partridge, L. Donald [University of New Mexico, Albuquerque, NM; Finnegan, Patrick Sean; Wolfley, Steven L.; Dagel, Daryl James; Spahn, Olga Blum; Harper, Jason C.; Pohl, Kenneth Roy; Mickel, Patrick R.; Lohn, Andrew; Marinella, Matthew

    2013-10-01

    The human brain (volume=1200cm3) consumes 20W and is capable of performing>10%5E16 operations/s. Current supercomputer technology has reached 1015 operations/s, yet it requires 1500m%5E3 and 3MW, giving the brain a 10%5E12 advantage in operations/s/W/cm%5E3. Thus, to reach exascale computation, two achievements are required: 1) improved understanding of computation in biological tissue, and 2) a paradigm shift towards neuromorphic computing where hardware circuits mimic properties of neural tissue. To address 1), we will interrogate corticostriatal networks in mouse brain tissue slices, specifically with regard to their frequency filtering capabilities as a function of input stimulus. To address 2), we will instantiate biological computing characteristics such as multi-bit storage into hardware devices with future computational and memory applications. Resistive memory devices will be modeled, designed, and fabricated in the MESA facility in consultation with our internal and external collaborators.

  17. Radionuclide transfer from forage plants into milk

    There is a lot of information regarding the transfer of radionuclides (iodine, caesium, strontium) which allows the transfer factor being calculated with high certainty. The transfer coefficients (forage-)plant/milk laid down in Paragraph 45 of the Radiation Protection Ordinance (Strahlenschutzverordnung) amount to 1.0x10-2 for iodine-131, 1.2x10-2 for caesium-137 and 2.0x10-3 for strontium-90. More recent calculated factors are markedly lower at the average. During milk processing, the greatest amount of radionuclides gets access to the whey or into the permeate after ultrafiltration of whey. In butter and cheese only minute amounts of caesium can be expected. (orig.)

  18. Examining School Improvement through the Lens of Principal and Teacher Flow of Influence in High-Achieving, High-Poverty Schools

    Murley, Lisa Downing; Keedy, John L.; Welsh, John F.

    2008-01-01

    Based on the social exchange theory of Homans, Gouldner, and Malinowski, this sociocultural analysis of three elementary schools focused on principal-teacher and teacher-teacher exchanges of instructional influence. Two questions were asked: (a) In what ways, if any, do principals and teachers in high-achieving, high-poverty schools exchange…

  19. Palatability of Forage Chicory Cultivars for Goats

    Sesquiterpene lactones (SL) in forage chicory (Cichorium intybus L.) may have anthelmintic activity against gastrointestinal parasites in sheep and goats, but have been implicated in poor palatability of forage. We used three levels of soil P fertilization to influence SL concentrations in three cu...

  20. A Study of Organizational Justice, Organizational Citizenship Behavior, and Student Achievement in High Schools

    Burns, W. R. Travis; DiPaola, Michael F.

    2013-01-01

    Emerging research suggests that teachers' perceptions of fairness with respect to interactions with school administrators, decision-making processes, and decision outcomes can contribute greatly to understanding effective schools. This study of Virginia public high schools used correlational analysis to measure the strength of the…

  1. The Effects of Learning Styles on High School Students' Achievement on a Mathematics Course

    Orhun, Nevin

    2013-01-01

    This study examined the relationship between learning styles of students and their success on a mathematics course. In this study, the categorization of high school students' learning style scores was defined. The given method for calculating the learning style scores was developed by the author. The purpose of this study was to raise the…

  2. World first in high level waste vitrification - A review of French vitrification industrial achievements

    Brueziere, J.; Chauvin, E. [AREVA, 1 place Jean Millier, 92084 Paris La Defense (France); Piroux, J.C. [Joint Vitrification Laboratory - LCV, Marcoule, BP171, 30207 Bagnols sur Ceze (France)

    2013-07-01

    AREVA has more than 30 years experience in operating industrial HLW (High Level radioactive Waste) vitrification facilities (AVM - Marcoule Vitrification Facility, R7 and T7 facilities). This vitrification technology was based on borosilicate glasses and induction-heating. AVM was the world's first industrial HLW vitrification facility to operate in-line with a reprocessing plant. The glass formulation was adapted to commercial Light Water Reactor fission products solutions, including alkaline liquid waste concentrates as well as platinoid-rich clarification fines. The R7 and T7 facilities were designed on the basis of the industrial experience acquired in the AVM facility. The AVM vitrification process was implemented at a larger scale in order to operate the R7 and T7 facilities in-line with the UP2 and UP3 reprocessing plants. After more than 30 years of operation, outstanding record of operation has been established by the R7 and T7 facilities. The industrial startup of the CCIM (Cold Crucible Induction Melter) technology with enhanced glass formulation was possible thanks to the close cooperation between CEA and AREVA. CCIM is a water-cooled induction melter in which the glass frit and the waste are melted by direct high frequency induction. This technology allows the handling of highly corrosive solutions and high operating temperatures which permits new glass compositions and a higher glass production capacity. The CCIM technology has been implemented successfully at La Hague plant.

  3. High Enrollment Course Success Factors in Virtual School: Factors Influencing Student Academic Achievement

    Liu, Feng; Cavanaugh, Cathy

    2011-01-01

    This paper describes a study of success factors in high enrollment courses in a K-12 virtual school learning environment. The influence of variables: time student spent in the learning management system (LMS), number of times logged into the LMS, teacher comment, participation in free or reduced lunch programs, student status in the virtual school…

  4. Achieving reversibility of ultra-high mechanical stress by hydrogen loading of thin films

    Nano-materials are commonly stabilized by supports to maintain their desired shape and size. When these nano-materials take up interstitial atoms, this attachment to the support induces mechanical stresses. These stresses can be high when the support is rigid. High stress in the nano-material is typically released by delamination from the support or by the generation of defects, e.g., dislocations. As high mechanical stress can be beneficial for tuning the nano-materials properties, it is of general interest to deduce how real high mechanical stress can be gained. Here, we show that below a threshold nano-material size, dislocation formation can be completely suppressed and, when delamination is inhibited, even the ultrahigh stress values of the linear elastic limit can be reached. Specifically, for hydrogen solved in epitaxial niobium films on sapphire substrate supports a threshold film thickness of 6 nm was found and mechanical stress of up to (−10 ± 1) GPa was reached. This finding is of basic interest for hydrogen energy applications, as the hydride stability in metals itself is affected by mechanical stress. Thus, tuning of the mechanical stress-state in nano-materials may lead to improved storage properties of nano-sized materials

  5. The Contributions of Vocational Education to Career Aspirations, Work Attitudes, and Academic Achievement in High School.

    Stone, James R., III

    1988-01-01

    The goal of the study was to determine the relationship between participation in marketing education, a vocational program, and the development of skills and attitudes with lifelong relevance. The conclusion was that high school vocational experience did not influence occupational aspirations for marketing education students. (JOW)

  6. Best practices in heterotrophic high-cell-density microalgal processes: achievements, potential and possible limitations

    Bumbak, F.; Cook, S.; Zachleder, Vilém; Hauser, S.; Kovar, K.

    2011-01-01

    Roč. 91, č. 1 (2011), 31-46. ISSN 0175-7598 Institutional research plan: CEZ:AV0Z50200510 Keywords : Heterotrophic growth * Microalgae * High-celldensity culture Subject RIV: EE - Microbiology, Virology Impact factor: 3.425, year: 2011

  7. Preparation for High School Chemistry: The Effects of a Summer School Course on Student Achievement

    Garland, Eva R.; Garland, Harry T.

    2006-01-01

    A summer course was developed with the goal of preparing girls to succeed in secondary school chemistry. Group work and mathematical, logical, and laboratory skills were stressed in the course, with minimal emphasis on memorization. Students who took the summer course ranked statistically higher during their first semester of high school chemistry…

  8. Self-Directed Activity-Based Learning and Achievement in High School Chemistry

    Bassett, Meighan M.; Martinez, James; Martin, Ellice P.

    2014-01-01

    The effects of student-directed activity-based learning (SDABL) were examined in two high school chemistry classes. Students in the SDABL class were given pretest results, a list of standards to be mastered, and a chart of learning activities categorized by difficulty level. They selected activities to meet their needs and preferences.…

  9. School-Wide Positive Behavior Support: Effects on Pennsylvania High School Achievement, Discipline, and Climate

    Fox, Jon David

    2013-01-01

    Teachers and administrators are faced with managing the behaviors of students while preparing for the high stakes testing associated with the No Child Left Behind Act. One program that has demonstrated positive results at the elementary and middle school level is the school-wide positive behavior support model (SWPBS). Limited research is…

  10. The Impact of High-Speed Internet Connectivity at Home on Eighth-Grade Student Achievement

    Kingston, Kent J.

    2013-01-01

    In the fall of 2008 Westside Community Schools - District 66, in Omaha, Nebraska implemented a one-to-one notebook computer take home model for all eighth-grade students. The purpose of this study was to determine the effect of a required yearlong one-to-one notebook computer program supported by high-speed Internet connectivity at school on (a)…

  11. The Influence of Momentary Classroom Goal Structures on Student Engagement and Achievement in High School Science

    Zaleski, Diana Janet

    2012-01-01

    Teachers' instructional practices fundamentally shape students' classroom experiences. However, it is still unclear what patterns of instructional practice are related to specific classroom goal structures, and how momentary changes in classroom goal structures affect students' momentary cognitive engagement in high school science.…

  12. High-speed dental radiography achieved with a kilohertz-range pulsed x-ray generator

    The development of a high-intensity kilohertz-range pulsed x-ray generator and its application to dental radiography are described. The pulsed x-ray generator consisted of the following major components: a constant high-voltage power supply, a high-voltage main condenser, a hot-cathode triode, a DC power supply for the filament (hot cathode), and a grid controller. The main condenser of 0.5 microF-100 kV in the pulser was charged from 50 to 70 kV by the power supply, and the electric charges in the condenser were discharged to the triode by the grid controller. To be exact, the tube voltage decreased during the discharging for generating pulsed x-rays, yet the maximum value was equivalent to the initial charging voltage of the main condenser. The maximum values of the tube current and the repetition rate were about 0.5 A and 30 kHz, respectively. The pulse width of the x-rays ranged from approximately 20 to 400 micros, and the x-ray intensity with a charging voltage of 70 kV and a total resistance of 5.1 MΩ was about 0.83 microC/kg at 1.0 m per pulse. Using this generator, high-speed dental radiography, e.g., delayed radiography and multiple-shot radiography, was performed

  13. Achieving reversibility of ultra-high mechanical stress by hydrogen loading of thin films

    Hamm, M.; Burlaka, V.; Wagner, S.; Pundt, A.

    2015-06-01

    Nano-materials are commonly stabilized by supports to maintain their desired shape and size. When these nano-materials take up interstitial atoms, this attachment to the support induces mechanical stresses. These stresses can be high when the support is rigid. High stress in the nano-material is typically released by delamination from the support or by the generation of defects, e.g., dislocations. As high mechanical stress can be beneficial for tuning the nano-materials properties, it is of general interest to deduce how real high mechanical stress can be gained. Here, we show that below a threshold nano-material size, dislocation formation can be completely suppressed and, when delamination is inhibited, even the ultrahigh stress values of the linear elastic limit can be reached. Specifically, for hydrogen solved in epitaxial niobium films on sapphire substrate supports a threshold film thickness of 6 nm was found and mechanical stress of up to (-10 ± 1) GPa was reached. This finding is of basic interest for hydrogen energy applications, as the hydride stability in metals itself is affected by mechanical stress. Thus, tuning of the mechanical stress-state in nano-materials may lead to improved storage properties of nano-sized materials.

  14. The Study Experiences of the High Achievers in a Competitive Academic Environment: A Cost of Success?

    Nordmo, Ivar; Samara, Akylina

    2009-01-01

    The present paper is a case study that explores the study experiences and possible costs of success for the students accepted into the professional program in psychology at the University of Bergen in Norway. In this highly competitive environment, between 500 and 1000 students compete for 36 places during the introduction year. The study is based…

  15. Using Reading Rate and Comprehension CBM to Predict High-Stakes Achievement

    Miller, Kelli Caldwell; Bell, Sherry Mee; McCallum, R. Steve

    2015-01-01

    Because of the increased emphasis on standardized testing results, scores from a high-stakes, end-of-year test (Tennessee Comprehensive Assessment Program [TCAP] Reading Composite) were used as the standard against which scores from a group-administered, curriculum-based measure (CBM), Monitoring Instructional Responsiveness: Reading (MIR:R), were…

  16. Achieving and Sustaining New Knowledge Development in High-Expectation Start-Ups

    Matricano, Diego

    2010-01-01

    In markets characterized by strong competition, new knowledge and new knowledge development are generally recognized as the key means for an enterprise to gain competitive advantage. This knowledge-based competitive advantage is critical for all commercial ventures, but is especially so for high-expectation start-ups (technology-based ventures…

  17. Overcoming Adversity: High-Achieving African American Youth's Perspectives on Educational Resilience

    Williams, Joseph M.; Bryan, Julia

    2013-01-01

    This qualitative multicase research study identified the home, school, and community factors and processes that contributed to the academic success of 8 urban, African American high school graduates from low-income, single-parent families. Ten main themes emerged: school-related parenting practices, personal stories of hardship, positive…

  18. Achieving highly-enhanced UV photoluminescence and its origin in ZnO nanocrystalline films

    Thapa, Dinesh; Huso, Jesse; Morrison, John L.; Corolewski, Caleb D.; McCluskey, Matthew D.; Bergman, Leah

    2016-08-01

    ZnO is an efficient luminescent material in the UV-range ∼3.4 eV with a wide range of applications in optical technologies. Sputtering is a cost-effective and relatively straightforward growth technique for ZnO films; however, most as-grown films are observed to contain intrinsic defects which can significantly diminish the desirable UV-emission. In this research the defect dynamics and optical properties of ZnO sputtered films were studied via post-growth annealing in Ar or O2 ambient, with X-ray diffraction (XRD), imaging, transmission and Urbach analysis, Raman scattering, and photoluminescence (PL). The imaging, XRD, Raman and Urbach analyses indicate significant improvement in crystal morphology and band-edge characteristics upon annealing, which is nearly independent of the annealing environment. The native defects specific to the as-grown films, which were analyzed via PL, are assigned to Zni related centers that luminesce at 2.8 eV. Their presence is attributed to the nature of the sputtering growth technique, which supports Zn-rich growth conditions. After annealing, in either environment the 2.8 eV center diminished accompanied by morphology improvement, and the desirable UV-PL significantly increased. The O2 ambient was found to introduce nominal Oi centers while the Ar ambient was found to be the ideal environment for the enhancement of the UV-light emission: an enhancement of ∼40 times was achieved. The increase in the UV-PL is attributed to the reduction of Zni-related defects, the presence of which in ZnO provides a competing route to the UV emission. Also, the effect of the annealing was to decrease the compressive stress in the films. Finally, the dominant UV-PL at the cold temperature regime is attributed to luminescent centers not associated with the usual excitons of ZnO, but rather to structural defects.

  19. Achievement of Runaway Electron Energy Dissipation by High-Z Gas Injection in DIII-D

    Hollmann, E. M.

    2014-10-01

    Disruption runaway electron (RE) formation followed by RE beam-wall strikes is a concern for future tokamaks, motivating the study of mitigation techniques to reduce the RE beam energy in a controlled manner. A promising approach for doing this is the injection of high-Z gas into the RE beam. Massive (100 torr-l) injection of high-Z gas into RE beams in DIII-D is shown to significantly dissipate both RE magnetic and kinetic energy. For example, injection of argon into a typical 300 kA current RE beam is observed to cause a drop in kinetic energy from 50 kJ to 10 kJ in 10 ms, thus rapidly reducing the damage-causing capability of the RE beam. Both the RE kinetic energy and pitch angle are important for determining the resulting wall damage, with high energy, high pitch angle electrons typically considered most dangerous. The RE energy distribution is found to be more skewed toward low energies than predicted by avalanche theory. The pitch angle is not found to be constant, as is frequently assumed, but is shown to drop from sin(θ) ~ 1 for energies less than 1 MeV to sin(θ) ~ 0 . 2 for energies greater than 10 MeV. Injection of high-Z impurities does not appear to change the overall shape of the energy or pitch angle distributions dramatically. The enhanced RE energy dissipation appears to be caused primarily via collisions with the cold plasma leading to line radiation. Synchrotron power loss only becomes significant in the absence of high-Z impurities, while radial transport loss of REs is seen to become dominant if the RE beam moves sufficiently close to the vessel walls. The experiments demonstrate that avalanche theory somewhat underestimates collisional dissipation of REs in the presence of high-Z atoms, even in the absence of radial transport losses, meaning that reducing RE wall damage in large tokamaks should be easier than previously expected. Supported by the US Department of Energy under DE-FG02-07ER54917 and DE-FC02-04ER54698.

  20. Different Gender Students' Participation in the High- and Low-achieving Middle School Questioning-orientated Biology Classrooms in Taiwan

    She, Hsiao-Ching

    2001-02-01

    This case study investigated gender-based differences in classroom participation through examining teacher-student interactions between a female biology teacher and two groups of middle school students, namely high achievers and low achievers. The female teacher used a questioning-orientated instructional strategy as her major teaching style which creates greater opportunities for student participation in biology learning. Classroom sessions were videotaped for one school year, then analysed for gender differences in question-and-answer patterns. The results showed that more teacher-initiated questions, teacher-directed interactions, and teacher feedback were given to males than females in both groups, but a large difference was found between the two groups of students. Girls in the low-achieving biology class (LABC) were more likely to participate at a rate comparable with their male classmates; girls answered more procedure questions and an equal percentage of process questions, called out approximately the same percentage of answers to undirected teacher-initiated questions, and received more instances of praise and follow-up questions. Contrary to what was observed in the high-achieving biology class (HABC), LABC girls initiated more questions than LABC boys.

  1. A simple method for detection of food foraging behavior in the rat: involvement of NMDA and dopamine receptors in the behavior.

    Li, F; Cao, W Y; Li, M B; Xu, Y; Zhang, J W; Zhang, J Y; Luo, X G; Dai, R P; Zhou, X F; Li, C Q

    2012-03-15

    Food foraging behavior involves food removing, hoarding, and competitive preying upon other animals. It is also associated with high cognitive functions such as investing effort into decision making, but no established laboratory model is available to detect the behaviors. In the present study, we have developed a novel laboratory rodent model to detect competitive, non-competitive, and no-hurdle foraging conditions that can mimic the corresponding environment in nature. We found that normal rats consistently foraged the food from a food container to the field and spread food into piles in the open field. There was no difference between male and female rats in the amount of foraged food in the competitive, non-competitive, and no-hurdle food foraging tests. The amount of foraged food was consistent each day for five consecutive days with a slight increase in following days. There was no significant difference in the amount of food foraged in the presence or absence of bedding materials. A dramatic decrease of foraged food was found in the rats after administration of haloperidol (dopamine D2 receptor antagonist) in the competitive, non-competitive, and no-hurdle food foraging tests. Treatment with MK-801 (non-competitive N-methy-D-aspartate receptor antagonist) reduced the foraged food in the competitive food foraging test, but did not affect the foraged food in the non-competitive and no-hurdle food foraging tests. Our study provides a simple but consistent analogue of natural food foraging behavior. Our study also suggests that dopaminergic and glutaminergic systems are differentially involved in the food foraging behaviors. PMID:22244978

  2. Effect of feeding extruded flaxseed with different forage: concentrate ratios on the performance of dairy cows.

    Neveu, C; Baurhoo, B; Mustafa, A

    2013-06-01

    Twenty Holstein cows were used in a Latin square design experiment with a 2×2 factorial arrangement to determine the effects of extruded flaxseed (EF) supplementation with 2 different forage to concentrate ratios on the performance of dairy cows. Extruded flaxseed diets contained 9% (dry matter basis) EF product which consisted of 75% EF and 25% ground alfalfa meal. Four lactating Holsteins cows fitted with rumen fistulae were used to determine the effects of dietary treatments on ruminal fermentation. Intakes of dry matter and crude protein were not influenced by dietary treatments. However, neutral detergent fiber intake was greater for the high-forage (8.4 kg/d) than the low-forage (7.8 kg/d) diet. Milk yield (average 40.2 kg/d) was similar for all dietary treatments. However, cows fed the high-forage diets produced milk with higher fat (3.76 vs. 2.97%) and total solids (12.58 vs. 11.95%) concentrations, but lower protein (3.19 vs. 3.33%) and lactose (4.66 vs. 4.72%) contents. Ruminal pH and total volatile fatty acid concentration were not affected by dietary treatments. However, feeding high forage relative to low forage diets increased molar proportion of acetate but decreased that of propionate. Ruminal NH3-N was reduced by feeding high forage relative to low forage diets. Milk fatty acid composition was altered by both forage level and EF supplementation. Feeding diets containing EF or low forage reduced the concentrations of saturated fatty acids and increased those of mono-unsaturated fatty acids. Concentrations of poly-unsaturated fatty acids were increased by feeding EF or low-forage diets. Extruded flaxseed supplementation increased milk fat α-linolenic acid content by 100% and conjugated linoleic acid by 54%. It was concluded that differences in animal performance and ruminal fermentation observed in this study were mostly due to differences in forage to concentrate ratio. However, EF supplementation caused most of the differences observed in milk

  3. Universality classes of foraging with resource renewal

    Chupeau, M.; Bénichou, O.; Redner, S.

    2016-03-01

    We determine the impact of resource renewal on the lifetime of a forager that depletes its environment and starves if it wanders too long without eating. In the framework of a minimal starving random-walk model with resource renewal, there are three universal classes of behavior as a function of the renewal time. For sufficiently rapid renewal, foragers are immortal, while foragers have a finite lifetime otherwise. In the specific case of one dimension, there is a third regime, for sufficiently slow renewal, in which the lifetime of the forager is independent of the renewal time. We outline an enumeration method to determine the mean lifetime of the forager in the mortal regime.

  4. Combining Harmonic Generation and Laser Chirping to Achieve High Spectral Density in Compton Sources

    Terzić, Balša; Krafft, Geoffrey A

    2015-01-01

    Recently various laser-chirping schemes have been investigated with the goal of reducing or eliminating ponderomotive line broadening in Compton or Thomson scattering occurring at high laser intensities. As a next level of detail in the spectrum calculations, we have calculated the line smoothing and broadening expected due to incident beam energy spread within a one-dimensional plane wave model for the incident laser pulse, both for compensated (chirped) and unchirped cases. The scattered compensated distributions are treatable analytically within three models for the envelope of the incident laser pulses: Gaussian, Lorentzian, or hyperbolic secant. We use the new results to demonstrate that the laser chirping in Compton sources at high laser intensities: (i) enables the use of higher order harmonics, thereby reducing the required electron beam energies; and (ii) increases the photon yield in a small frequency band beyond that possible with the fundamental without chirping. This combination of chirping and h...

  5. The study experiences of the high achievers in a competitive academic environment: A cost of success?

    Nordmo, Ivar; Samara, Akylina

    2009-01-01

    The present paper is a case study that explores the study experiences and possible costs of success for the students accepted into the professional program in psychology at the University of Bergen in Norway. In this highly competitive environment, between 500 and 1000 students compete for 36 places during the introduction year. The study is based on 31 students' written narratives about their studying experiences during the introductory year in psychology. The data were analys...

  6. In Search of Variables Distinguishing Low and High Achievers in Music Sight Reading Task

    Ligges, Uwe; Weihs, Claus; Kopiez, Reinhard; Lee, Ji In

    2004-01-01

    The unrehearsed performance of music, called ?sight reading? (SR), is a basic skill for all musicians. Despite the merits of expertise theory, there is no comprehensive model which can classify subjects into high and low performance groups. This study is the first that classifies subjects and is based on an extensive experiment measuring the total SR performance of 52 piano students. Classification methods (cluster analysis, classification tree, linear discriminant analysis) were applied. Res...

  7. Achieving large linear elasticity and high strength in bulk nanocompsite via synergistic effect

    Hao, Shijie; Cui, Lishan; Guo, Fangmin; Liu, Yinong; Shi, Xiaobin; Jiang, Daqiang; Brown, Dennis E.; Ren, Yang

    2015-03-01

    Elastic strain in bulk metallic materials is usually limited to only a fraction of 1%. Developing bulk metallic materials showing large linear elasticity and high strength has proven to be difficult. Here, based on the synergistic effect between nanowires and orientated martensite NiTi shape memory alloy, we developed an in-situ Nb nanowires -orientated martensitic NiTi matrix composite showing an ultra-large linear elastic strain of 4% and an ultrahigh yield strength of 1.8 GPa. This material also has a high mechanical energy storage efficiency of 96% and a high energy storage density of 36 J/cm3 that is almost one order of larger than that of spring steel. It is demonstrated that the synergistic effect allows the exceptional mechanical properties of nanowires to be harvested at macro scale and the mechanical properties of matrix to be greatly improved, resulting in these superior properties. This study provides new avenues for developing advanced composites with superior properties by using effective synergistic effect between components.

  8. Flexible foraging shapes the topology of plant-pollinator interaction networks.

    Spiesman, Brian J; Gratton, Claudio

    2016-06-01

    In plant-pollinator networks, foraging choices by pollinators help form the connecting links between species. Flexible foraging should therefore play an important role in defining network topology. Factors such as morphological trait complementarity limit a pollinator's pool of potential floral resources, but which potential resource species are actually utilized at a location depends on local environmental and ecological context. Pollinators can be highly flexible foragers, but the effect of this flexibility on network topology remains unclear. To understand how flexible foraging affects network topology, we examined differences between sets of locally realized interactions and corresponding sets of potential interactions within 25 weighted plant-pollinator networks in two different regions of the United States. We examined two possible mechanisms for flexible foraging effects on realized networks: (1) preferential targeting of higher-density plant resources, which should increase network nestedness, and (2) context-dependent resource partitioning driven by interspecific competition, which should increase modularity and complementary specialization. We found that flexible foraging has strong effects on realized network topology. Realized connectance was much lower than connectance based on potential interactions, indicating a local narrowing of diet breadth. Moreover, the foraging choices pollinators made, which particular plant species to visit and at what rates, resulted in networks that were significantly less nested and significantly more modular and specialized than their corresponding networks of potential interactions. Preferentially foraging on locally abundant resources was not a strong driver of the realization of potential interactions. However, the degree of modularity and complementary specialization both increased with the number of competing pollinator species and with niche availability. We therefore conclude that flexible foraging affects realized

  9. Sex-related differences in the trade-off between foraging and vigilance in a granivorous forager.

    Thibaut Powolny

    Full Text Available The relationship between intake rate and food density can provide the foundation for models that predict the spatiotemporal distribution of organisms across a range of resource densities. The functional response, describing the relationship between resource density and intake rate is often interpreted mechanistically as the relationships between times spend searching and handling. While several functional response models incorporate anti-predator vigilance (defined here as an interruption of feeding or some other activity to visually scan the environment, directed mainly towards detecting potential predators, the impacts of environmental factors influencing directly anti-predator vigilance remains unclear. We examined the combined effects of different scenarios of predation risk and food density on time allocation between foraging and anti-predator vigilance in a granivorous species. We experimentally exposed Skylarks to various cover heights and seed densities, and measured individual time budget and pecking and intake rates. Our results indicated that time devoted to different activities varied as a function of both seed density and cover height. Foraging time increased with seed density for all cover heights. Conversely, an increased cover height resulted in a decreased foraging time. Contrary to males, the decreased proportion of time spent foraging did not translate into a foraging disadvantage for females. When vegetation height was higher, females maintained similar pecking and intake rates compared to intermediate levels, while males consistently decreased their energy gain. This difference in anti-predator responses suggests a sexually mediated strategy in the food-safety trade-off: when resource density is high a females would adopt a camouflage strategy while an escape strategy would be adopted by males. In other words, males would leave risky-areas, whereas females would stay when resource density is high. Our results suggest that

  10. Co-evolution of learning complexity and social foraging strategies

    Arbilly, Michal; Motro, Uzi; Marcus W Feldman; Lotem, Arnon

    2010-01-01

    Variation in learning abilities within populations suggests that complex learning may not necessarily be more adaptive than simple learning. Yet, the high cost of complex learning cannot fully explain this variation without some understanding of why complex learning is too costly for some individuals but not for others. Here we propose that different social foraging strategies can favor different learning strategies (that learn the environment with high or low resolution), thereby maintaining...

  11. Harvest-related edge effects on prey availability and foraging of hooded warblers in a bottomland hardwood forest.

    John Kilgo

    2005-04-20

    The effects of harvest-created canopy gaps in bottomland hardwood forests on arthropod abundance and, hence, the foraging ecology of birds are poorly understood. I predicted that arthropod abundance would be high near edges of group-selection harvest gaps and lower in the surrounding forest, and that male Hooded Warblers (Wilsonia citrina) foraging near gaps would find more prey per unit time than those foraging in the surrounding forest. In fact, arthropod abundance was greater >100 m from a gap edge than at 0-30 m or 30-100 m from an edge, due to their abundance on switchcane (Arundinaria gigantea); arthropods did not differ in abundance among distances from gaps on oaks (Quercus spp.) or red maple (Acer rubrum). Similarly, Hooded Warbler foraging attack rates were not higher near gap edges: when foraging for fledglings, attack rate did not differ among distances from gaps, but when foraging for themselves, attack rates actually were lower 0-30 m from gap edges than 30-100 m or >100 m from a gap edge. Foraging attack rate was positively associated with arthropod abundance. Hooded Warblers apparently encountered fewer prey and presumably foraged less efficiently where arthropods were least abundant, i.e., near gaps. That attack rates among birds foraging for fledglings were not affected by distance from gap (and hence arthropod abundance) suggests that prey availability may not be limiting at any location across the forest, despite the depressing effects of gaps on arthropod abundance.

  12. Achieving large linear elasticity and high strength in bulk nanocompsite via synergistic effect

    Shijie Hao; Lishan Cui; Fangmin Guo; Yinong Liu; Xiaobin Shi; Daqiang Jiang; Dennis E. Brown; Yang Ren

    2015-01-01

    Elastic strain in bulk metallic materials is usually limited to only a fraction of 1%. Developing bulk metallic materials showing large linear elasticity and high strength has proven to be difficult. Here, based on the synergistic effect between nanowires and orientated martensite NiTi shape memory alloy, we developed an in-situ Nb nanowires -orientated martensitic NiTi matrix composite showing an ultra-large linear elastic strain of 4% and an ultrahigh yield strength of 1.8 GPa. This materia...

  13. An examination of the saturation microstructures achieved in ultrafine-grained metals processed by high-pressure torsion

    Shima Sabbaghianrad; Jittraporn Wongsa-Ngam; Megumi Kawasaki; Terence G. Langdon

    2014-01-01

    Experiments were conducted on two commercial alloys, a Cu–0.1%Zr alloy and an Al-7075 aluminum alloy, to investigate the significance of the saturation microstructure which is achieved after processing by high-pressure torsion (HPT). Samples were processed by HPT and also by a combination of equal-channel angular pressing (ECAP) followed by HPT. The results show that the saturation conditions are dependent upon the grain size in the material immediately prior to the HPT processing. Additional...

  14. The Relationship between Motivations and Self-Learning and the English Language Achievement in Secondary High School Students

    Hadriana Hadriana; Mohd. Arif Ismail; Mahdum Mahdum

    2013-01-01

    This study aims to determine the level of motivation and relationship of intrinsic and extrinsic motivations and self-learning concerning students’ achievement in the English language, in relevance with their determination and the use of English to derive knowledge and as a medium of communication. A total of 120 secondary high school students in Pekanbaru Riau, Indonesia were randomly chosen as sample to evaluate and determine the influence of internal and external factors, as well as self-l...

  15. Doping in the Mixed Layer to Achieve High Brightness and Efficiency Organic Light Emitting Devices

    高文宝; 杨开霞; 刘宏宇; 冯晶; 刘式墉

    2002-01-01

    Doping in the mixed layer was introduced to fabricate high brightness and high efficiency organic light emitting devices. In these devices, a copper phthalocyanine (CuPc) film acts as the buffer layer, a naphthylphenybiphenyl amine (NPB) film as the hole transport layer and a tris(8-hydroxyquinolinolate)aluminium (Alq3) film as the electron transport layer. The luminescent layer consists of the mixture of NPB, Alq3 (to be called the mixed layer), and an emitting dopant 5,6,11,12-petraphenylnaphthacene (rubrene), where the concentration of NPB declined and the concentration of Alq3 was increased gradually in the deposition process. Adopting this doping mixed layer, the device exhibits the maximum emission of 49300cd/m2 at 35 V and the maximum efficiency of 7.96cd/A at 10.5 V, which have been improved by two times in comparison with conventional doped devices. We attribute this improvement to the effective confinement of carriers in the mixed layer, which leads to the increase of the recombination efficiency of carriers.

  16. The design of an animal PET: flexible geometry for achieving optimal spatial resolution or high sensitivity.

    Weber, S; Terstegge, A; Herzog, H; Reinartz, R; Reinhart, P; Rongen, F; Müller-Gärtner, H W; Halling, H

    1997-10-01

    We present the design of a positron emission tomograph (PET) with flexible geometry dedicated to in vivo studies of small animals (TierPET). The scanner uses two pairs of detectors. Each detector consists of 400 small individual yttrium aluminum perovskite (YAP) scintillator crystals of dimensions 2 x 2 x 15 mm3, optically isolated and glued together, which are coupled to position-sensitive photomultiplier tubes (PSPMT's). The detector modules can be moved in a radial direction so that the detector-to-detector spacing can be varied. Special hardware has been built for coincidence detection, position detection, and real-time data acquisition, which is performed by a PC. The single-event data are transferred to workstations where the radioactivity distribution is reconstructed. The dimensions of the crystals and the detector layout are the result of extensive simulations which are described in this report, taking into account sensitivity, spatial resolution and additional parameters like parallax error or scatter effects. For the three-dimensional (3-D) reconstruction a genuine 3-D expectation-maximization (EM)-algorithm which can include the characteristics of the detector system has been implemented. The reconstruction software is flexible and matches the different detector configurations. The main advantage of the proposed animal PET scanner is its high flexibility, allowing the realization of various detector-system configurations. By changing the detector-to-detector spacing, the system is capable of either providing good spatial resolution or high sensitivity for dynamic studies of pharmacokinetics. PMID:9368124

  17. A noninvasive high frequency oscillation ventilator: Achieved by utilizing a blower and a valve

    Yuan, YueYang; Sun, JianGuo; Wang, Baicun; Feng, Pei; Yang, ChongChang

    2016-02-01

    After the High Frequency Oscillatory Ventilation (HFOV) has been applied in the invasive ventilator, the new technique of noninvasive High Frequency Oscillatory Ventilation (nHFOV) which does not require opening the patient's airway has attracted much attention from the field. This paper proposes the design of an experimental positive pressure-controlled nHFOV ventilator which utilizes a blower and a special valve and has three ventilation modes: spontaneous controlled ventilation combining HFOV, time-cycled ventilation combining HFOV (T-HFOV), and continuous positive airway pressure ventilation combining HFOV. Experiments on respiratory model are conducted and demonstrated the feasibility of using nHFOV through the control of fan and valve. The experimental ventilator is able to produce an air flow with small tidal volume (VT) and a large minute ventilation volume (MV) using regular breath tubes and nasal mask (e.g., under T-HFOV mode, with a maximum tidal volume of 100 ml, the minute ventilation volume reached 14 400 ml). In the process of transmission, there is only a minor loss of oscillation pressure. (Under experimental condition and with an oscillation frequency of 2-10 Hz, peak pressure loss was around 0%-50% when it reaches the mask.)

  18. Influence of milk production potential on forage dry matter intake by multiparous and primiparous Brangus females.

    Johnson, C R; Lalman, D L; Brown, M A; Appeddu, L A; Buchanan, D S; Wettemann, R P

    2003-07-01

    Brangus cows (n = 29) were used in three experiments to evaluate the effects of parity (multiparous vs. primiparous) and potential genetic merit for milk production (high vs. low) on forage intake during late gestation, early lactation, and late lactation. Cows were selected for milk production based on their sire's EPD for milk production (MEPD). Cows had ad libitum access to (130% of previous 2-d average intake) low-quality hay (5.3% CP and 76% NDF), and cottonseed meal was supplemented to ensure adequate degradable intake protein. All females were adapted to diets for at least 7 d, and individual intake data were collected for 9 d. During the lactation trials, actual milk production was determined using a portable milking machine following a 12-h separation from calves. During late gestation, multiparous cows consumed 24% more (P = 0.01) forage DM (kg/d) than primiparous cows; however, parity class did not influence forage intake when intake was expressed relative to BW. Furthermore, MEPD did not influence forage intake during late gestation. During early lactation, multiparous cows produced 66% more (P < 0.001) milk than primiparous cows, and high MEPD tended (P = 0.10) to produce more milk than low MEPD. Multiparous cows consumed 19% more (P < 0.0001) forage DM than did primiparous cows when expressed on an absolute basis, but not when expressed on a BW basis. High-MEPD cows consumed 8% more (P < 0.05) forage DM than did low-MEPD cows. During late lactation, multiparous cows produced 84% more milk than primiparous cows, although MEPD did not influence (P = 0.40) milk yield. In addition, multiparous cows consumed 17% more (P < 0.01) forage DM per day than primiparous cows, but when intake was expressed relative to BW, neither parity nor MEPD influenced forage DMI during late lactation. Milk yield and BW explained significant proportions of the variation in forage DMI during early and late lactation. Each kilogram increase in milk yield was associated with a 0

  19. A study of the relationships between "highly qualified" status, instructional practices, and students' science achievement in three high poverty Louisiana school systems

    Clayton, Michelle

    Using a mixed methods research design, the author examined the relationships between "highly qualified" status, instructional practices, and students' science achievement for six third grade teachers in three high poverty Louisiana school systems. The study analyzed qualitative and quantitative data for three science classes taught by "highly qualified" teachers and three science classes taught by "non-highly qualified" teachers. The qualitative portion of the study was conducted through classroom observations, teacher interviews, and lesson plan reviews. The qualitative data was coded and triangulated to determine whether the instructional practices of each teacher were more "teacher-centered" or "student-centered." The qualitative data analysis indicated various patterns and consistencies in the instructional practices used by the "highly qualified" and "non-highly qualified" teachers selected for this study. The quantitative portion of the study involved analysis of the students' science achievement data for the six third grade science teachers selected for the study. Science achievement was measured by the third grade Integrated Louisiana Education Assessment Program (iLEAP) scores. A two-way ANOVA indicated that there were statistically significant differences in the mean scores of the three high poverty Louisiana school systems as well as the students taught by "highly qualified" and "non-highly qualified" teachers and the interactions between the two: F(2, 123) = 46.99, p teachers in the study: F (5, 123) = 20.386, p teachers' scores significantly differed from each other.

  20. NEMO5: Achieving High-end Internode Communication for Performance Projection Beyond Moore's Law

    Andrawis, Robert; Charles, James; Fang, Jianbin; Fonseca, Jim; He, Yu; Klimeck, Gerhard; Jiang, Zhengping; Kubis, Tillmann; Mejia, Daniel; Lemus, Daniel; Povolotskyi, Michael; Rubiano, Santiago Alonso Perez; Sarangapani, Prasad; Zeng, Lang

    2015-01-01

    Electronic performance predictions of modern nanotransistors require nonequilibrium Green's functions including incoherent scattering on phonons as well as inclusion of random alloy disorder and surface roughness effects. The solution of all these effects is numerically extremely expensive and has to be done on the world's largest supercomputers due to the large memory requirement and the high performance demands on the communication network between the compute nodes. In this work, it is shown that NEMO5 covers all required physical effects and their combination. Furthermore, it is also shown that NEMO5's implementation of the algorithm scales very well up to about 178176CPUs with a sustained performance of about 857 TFLOPS. Therefore, NEMO5 is ready to simulate future nanotransistors.

  1. Integrated Operating Scenario to Achieve 100-Second, High Electron Temperature Discharge on EAST

    Qian, Jinping; Gong, Xianzu; Wan, Baonian; Liu, Fukun; Wang, Mao; Xu, Handong; Hu, Chundong; Wang, Liang; Li, Erzhong; Zeng, Long; Ti, Ang; Shen, Biao; Lin, Shiyao; Shao, Linming; Zang, Qing; Liu, Haiqing; Zhang, Bin; Sun, Youwen; Xu, Guosheng; Liang, Yunfeng; Xiao, Bingjia; Hu, Liqun; Li, Jiangang; EAST Team

    2016-05-01

    Stationary long pulse plasma of high electron temperature was produced on EAST for the first time through an integrated control of plasma shape, divertor heat flux, particle exhaust, wall conditioning, impurity management, and the coupling of multiple heating and current drive power. A discharge with a lower single null divertor configuration was maintained for 103 s at a plasma current of 0.4 MA, q95 ≈7.0, a peak electron temperature of >4.5 keV, and a central density ne(0)∼2.5×1019 m‑3. The plasma current was nearly non-inductive (Vloop energy confinement of stationary plasma on EAST. It further introduced an example of integrated “hybrid” operating scenario of interest to ITER and CFETR. supported by the National Magnetic Confinement Fusion Science Foundation of China (Nos. 2015GB102000 and 2014GB103000)

  2. The Impact of Attending a School with High-Achieving Peers: Evidence from the New York City Exam Schools

    Will Dobbie; Roland G. Fryer Jr.

    2014-01-01

    This paper uses data from three prominent exam high schools in New York City to estimate the impact of attending a school with high-achieving peers on college enrollment and graduation. Our identification strategy exploits sharp discontinuities in the admissions process. Applicants just eligible for an exam school have peers that score 0.17 to 0.36 standard deviations higher on eighth grade state tests and that are 6.4 to 9.5 percentage points less likely to be black or Hispanic. However, exp...

  3. Achieving precision in high density batch mode micro-electro-discharge machining

    This paper reports a parametric study of batch mode micro-electro-discharge machining (µEDM) of high density features in stainless steel. Lithographically fabricated copper tools with single cross, parallel line and 8 × 8 circle/square array features of 5–100 µm width and 5–75 µm spacing were used to quantify trends in machining tolerance and the impact of debris accumulation. As the tool feature density is increased, debris accumulation effects begin to dominate, eventually degrading both tool and workpiece. Two independent techniques for mitigating this debris buildup are separately investigated. The first is a passivation coating which suppresses spurious discharges triggered from the sidewalls of the machining tool. By this method, the mean tool wear rate decreases from a typical of about 34% to 1.7% and machining non-uniformity reduces from 4.9 µm to 1.1 µm across the workpiece. The second technique involves a two-step machining process that enhances the hydrodynamic removal of machining debris compared to standard methods. This improves surface and edge finish, machining time and tool wear

  4. A luciferin analogue generating near-infrared bioluminescence achieves highly sensitive deep-tissue imaging.

    Kuchimaru, Takahiro; Iwano, Satoshi; Kiyama, Masahiro; Mitsumata, Shun; Kadonosono, Tetsuya; Niwa, Haruki; Maki, Shojiro; Kizaka-Kondoh, Shinae

    2016-01-01

    In preclinical cancer research, bioluminescence imaging with firefly luciferase and D-luciferin has become a standard to monitor biological processes both in vitro and in vivo. However, the emission maximum (λmax) of bioluminescence produced by D-luciferin is 562 nm where light is not highly penetrable in biological tissues. This emphasizes a need for developing a red-shifted bioluminescence imaging system to improve detection sensitivity of targets in deep tissue. Here we characterize the bioluminescent properties of the newly synthesized luciferin analogue, AkaLumine-HCl. The bioluminescence produced by AkaLumine-HCl in reactions with native firefly luciferase is in the near-infrared wavelength ranges (λmax=677 nm), and yields significantly increased target-detection sensitivity from deep tissues with maximal signals attained at very low concentrations, as compared with D-luciferin and emerging synthetic luciferin CycLuc1. These characteristics offer a more sensitive and accurate method for non-invasive bioluminescence imaging with native firefly luciferase in various animal models. PMID:27297211

  5. Integrated Operating Scenario to Achieve 100-Second, High Electron Temperature Discharge on EAST

    QIAN Jinping; GONG Xianzu; WAN Baonian; LIU Fukun; WANG Mao; XU Handong; HU Chundong

    2016-01-01

    Stationary long pulse plasma of high electron temperature was produced on EAST for the first time through an integrated control of plasma shape,divertor heat flux,particle exhaust,wall conditioning,impurity management,and the coupling of multiple heating and current drive power.A discharge with a lower single null divertor configuration was maintained for 103 s at a plasma current of 0.4 MA,q95 ≈7.0,a peak electron temperature of >4.5 keV,and a central density ne(0)~ 2.5×1019 m-3.The plasma current was nearly non-inductive (Vloop <0.05 V,poloidal beta ~ 0.9) driven by a combination of 0.6 MW lower hybrid wave at 2.45 GHz,1.4 MW lower hybrid wave at 4.6 GHz,0.5 MW electron cyclotron heating at 140 GHz,and 0.4 MW modulated neutral deuterium beam injected at 60 kV.This progress demonstrated strong synergy of electron cyclotron and lower hybrid electron heating,current drive,and energy confinement of stationary plasma on EAST.It further introduced an example of integrated “hybrid” operating scenario of interest to ITER and CFETR.

  6. Achieving a high coverage – the challenge of controlling HIV spread in heroin users

    Meng Jin-Huai

    2007-02-01

    Full Text Available Abstract In China, the national plan to open 1000 methadone clinics over a five-year period provides a unique opportunity to assess the impacts of harm reduction in a country with concentrated HIV epidemic amongst heroin users. To track the progress of this public health response, data were collected from the first methadone clinic in Liuzhou, Guangxi, a province with a high HIV prevalence. In the first 15 months of its operation, a cumulative total of 488 heroin users, 86% of which male, had joined the programme. The first dose of methadone was given efficiently at a median of 2 days after registration. Of the 240 heroin users attending the clinic in August 2006, 61% took methadone for four days or more each week. The number of active methadone users, however, leveled off at around 170 after the first two months, despite the availability of capacity to deliver more services. The reasons for this observation are: firstly, the provision of one single service that may not be convenient to all heroin users; and secondly, concerns of heroin users who may feel insecure to come forward. As broad coverage is essential in ultimately reducing HIV risk, a low threshold approach is crucial, which should be supported by the removal of social obstacles and a refinement of the administrative procedures.

  7. Achieving the Benefits of a High-Potassium, Paleolithic Diet, Without the Toxicity.

    Palmer, Biff F; Clegg, Deborah J

    2016-04-01

    The average US dietary intake of K(+) is well below the current recommended nutritional requirements. This deficiency is even more striking when comparing our current intake with that of our ancestors, who consumed large amounts of dietary K(+). K(+) deficiency has been implicated in many diseases including cardiovascular disease, kidney stones, and osteoporosis. Importantly, dietary supplementation of K(+) has favorable effects on reducing blood pressure, decreasing the risk of stroke, improving bone health, and reducing the risk of nephrolithiasis. For this comprehensive review, we scanned the literature using PubMed and MEDLINE using the following search terms: potassium intake, renal potassium excretion, and prevention of hyperkalemia. Articles were selected for inclusion if they represented primary data or review articles published between 1980 and 2015 in high-impact journals. The normal kidney has the capacity to tightly regulate K(+) homoeostasis. We discuss new findings with respect to sensing mechanisms by which the kidney maintains K(+) homeostasis in the gastrointestinal tract and distal tubule. There are widely prescribed hypertensive medications that cause hyperkalemia and thus require dietary K(+) restriction. We conclude by discussing newly approved drugs capable of binding K(+) in the gastrointestinal tract and speculate that this new pharmacology might allow diet liberalization in patients at risk for hyperkalemia, affording them the numerous benefits of a K(+)-rich diet. PMID:26948054

  8. Mathematical and numerical models to achieve high speed with special-purpose parallel processors

    Historically, safety analyses and plant dynamic simulations have been and still are being carried out be means of detailed FORTRAN codes on expensive mainframe computers in time-consuming batch processing mode. These codes have grown to be so expensive to execute that their utilization depends increasingly on the availability of very expensive supercomputers. Thus, advanced technology for high-speed, low-cost, and accurate plant dynamic simulations is very much needed. Ideally, a low-cost facility based on a modern minicomputer can be dedicated to the staff of a power plant, which is easy and convenient to use, and which can simulate realistically plant transients at faster than real-time speeds. Such a simulation capability can enhance safety and plant utilization. One such simulation facility that has been developed is the Brookhaven National Laboratory (BNL) Plant Analyzer, currently set up for boiling water reactor plant simulations at up to seven times faster than real-time process speeds. The principal hardware components of the BNL Plant Analyzer are two units of special-purpose parallel processors, the AD10 of Applied Dynamics International and a PDP-11/34 host computer

  9. A luciferin analogue generating near-infrared bioluminescence achieves highly sensitive deep-tissue imaging

    Kuchimaru, Takahiro; Iwano, Satoshi; Kiyama, Masahiro; Mitsumata, Shun; Kadonosono, Tetsuya; Niwa, Haruki; Maki, Shojiro; Kizaka-Kondoh, Shinae

    2016-01-01

    In preclinical cancer research, bioluminescence imaging with firefly luciferase and D-luciferin has become a standard to monitor biological processes both in vitro and in vivo. However, the emission maximum (λmax) of bioluminescence produced by D-luciferin is 562 nm where light is not highly penetrable in biological tissues. This emphasizes a need for developing a red-shifted bioluminescence imaging system to improve detection sensitivity of targets in deep tissue. Here we characterize the bioluminescent properties of the newly synthesized luciferin analogue, AkaLumine-HCl. The bioluminescence produced by AkaLumine-HCl in reactions with native firefly luciferase is in the near-infrared wavelength ranges (λmax=677 nm), and yields significantly increased target-detection sensitivity from deep tissues with maximal signals attained at very low concentrations, as compared with D-luciferin and emerging synthetic luciferin CycLuc1. These characteristics offer a more sensitive and accurate method for non-invasive bioluminescence imaging with native firefly luciferase in various animal models. PMID:27297211

  10. High resolution anoscopy may be useful in achieving reductions in anal cancer local disease failure rates.

    Goon, P; Morrison, V; Fearnhead, N; Davies, J; Wilson, C; Jephcott, C; Sterling, J; Crawford, R

    2015-05-01

    Anal cancer is uncommon, with an incidence rate of 0.5-1.0 per 100,000 of the population but incidence rates have been steadily increasing over the last 3 decades. Biological and epidemiological evidence have been mounting and demonstrate that anal cancer has many similarities to cervical cancer, especially in regard to its aetiology. High-resolution anoscopy (HRA) of the anal region – analogous to colposcopy of the cervix, is a technique that is not well-known in the medical and surgical fraternity. Evidence to support the use of HRA for detection and treatment in the surveillance of AIN exists and strongly suggests that it is beneficial, resulting in reduced rates of cancer progression. Pilot data from our study showed a local disease failure rate of 1.73 per 1000 patient-months compared with a published rate of 9.89 per 1000 patient-months. This demonstrates a 5.72-fold reduction in local disease failure rates of patients with T1-T3 tumours; the data therefore suggests that use of HRA for detection and treatment in surveillance of anal cancer patients will help prevent local regional relapse at the anal site. There is an urgent need for a large, randomised controlled clinical trial to definitively test this hypothesis. PMID:24373061

  11. Stochastic resonance and the evolution of Daphnia foraging strategy

    Search strategies are currently of great interest, with reports on foraging ranging from albatrosses and spider monkeys to microzooplankton. Here, we investigate the role of noise in optimizing search strategies. We focus on the zooplankton Daphnia, which move in successive sequences consisting of a hop, a pause and a turn through an angle. Recent experiments have shown that their turning angle distributions (TADs) and underlying noise intensities are similar across species and age groups, suggesting an evolutionary origin of this internal noise. We explore this hypothesis further with a digital simulation (EVO) based solely on the three central Darwinian themes: inheritability, variability and survivability. Separate simulations utilizing stochastic resonance (SR) indicate that foraging success, and hence fitness, is maximized at an optimum TAD noise intensity, which is represented by the distribution's characteristic width, σ. In both the EVO and SR simulations, foraging success is the criterion, and the results are the predicted characteristic widths of the TADs that maximize success. Our results are twofold: (1) the evolving characteristic widths achieve stasis after many generations; (2) as a hop length parameter is changed, variations in the evolved widths generated by EVO parallel those predicted by SR. These findings provide support for the hypotheses that (1) σ is an evolved quantity and that (2) SR plays a role in evolution. (communication)

  12. Achieving high quality long-term care for elderly people: consumers' wishes and providers' responsibilities.

    Morse, R; Jenkinson, D

    1995-01-01

    The organisation of long-term care for older people has major implications for all hospital and community health services. However, even health professionals have a poor understanding of the structure and purpose of long-term care and national professional bodies are still not giving enough attention to the issues involved. In the wider context, care of disabled older people has received little public debate in the UK despite the ethical, social, and financial issues involved and despite the recent major organisational changes in the health service. The past ten years have seen a huge expansion in private residential and nursing homes with a concomitant fall in NHS long-stay beds. Currently, approximately 500,000 elderly people in the UK are living in some form of long-stay care facility, and many other elderly people with multiple disabilities are being supported at home and should also be included under the umbrella of long-term care. Ensuring appropriate, equitable, and high-quality care is a responsibility not only for health and social services but also for society as a whole. This conference, organised jointly by the Royal College of Physicians, the British Geriatrics Society, and Age Concern England, with support from the Department of Health, was a much-needed and welcomed initiative. Over 200 delegates attended, consisting of doctors (geriatricians, psychiatrists, general practitioners), nurses (public and private sector), social services representatives, Department of Health representatives, managers of nursing homes, and members of charities such as Age Concern and the Relatives Association. PMID:7658422

  13. The National COSEE Network's decade of assisting scientists to achieve high-quality Broader Impacts

    Hotaling, L. A.; Yoder, J. A.; Scowcroft, G.

    2012-12-01

    Many ocean scientists struggle with defining Broader Impact (BI) activities that will satisfy reviewers or fit within budget and time constraints, and many scientists are uncertain as to how to find assistance in crafting sound BI plans. In 2002, the National Centers for Ocean Sciences Education Excellence (COSEE) Network began engaging and connecting scientists and educators to transform ocean sciences education. COSEE's success in engaging scientists in BI activities is due to the Network's ability to find and create opportunities for education and outreach, assist scientists in designing programs that feature their research, and support scientists with courses, workshops and tools, which assist them in becoming better communicators of their research to non-scientific audiences. Among its most significant accomplishments to date is the development of a network of ocean scientists that is connected to education and outreach professionals, formal K-12 educators and students, informal science professionals, learning sciences experts, and graduate and undergraduate students. In addition to networking, COSEE Centers have developed and implemented the Ocean Literacy Principles and Fundamental Concepts and the Ocean Literacy Scope and Sequence for grades K-12. COSEE has also helped engage scientists with public audiences, facilitating the use of real-time ocean observing systems (OOS) data in formal and informal education settings, creating new distance learning and online resources for ocean sciences education, and promoting high quality ocean sciences education and outreach in universities and formal/informal venues. The purpose of this presentation is to review several tools that the COSEE Network has developed to assist ocean scientists with BI activities and to describe the Network's efforts to prepare young scientists to communicate their research to non-expert audiences.

  14. The effect of online quizzes on student achievement in high school chemistry

    Deeter, Christopher L.

    The idea of student engagement has come to the forefront of the United States educational system over the past decade. Student engagement requires learners to be actively involved in all stages of the learning process. This study focuses on the use of online quizzes in the chemistry classroom as a means to help students become more engaged in their learning outside of the classroom. Students were given three different types of online quizzes over the course of a chemistry chapter. Student scores on end of the chapter examinations was used to determine whether there was a significant difference in the amount of learning that occurred when a student took each of the three types of online quizzes. Students in a private parochial high school chemistry class completed online quizzes over the course of a semester. The quizzes were taken after completing assigned readings from the chemistry text. After each reading, a third of the students took online multiple-choice quizzes, a third took a paragraph quiz, and a third took no quiz. Scores received from end of chapter tests were evaluated to determine if the impact each of the quiz types had on the learning. All statistical analysis was done using SPSS using two-way split plot ANOVA with condition (paragraph, multiple-choice, nothing) as the within subject factor and group (A, B, C) as between subject factor. The data indicates that there was no significance within the condition F (1.877, 90.087) =.996, p>.05, or the interaction results. F (3.754, 90.087) =.509, p>.05. The data indicated that the effect of group was not significant either. F (2, 48) =.981, p>.05. Interviews undertaken to explain this outcome discovered that students did not become engaged with the content until the night before each test. When they did so, they used a teacher-provided study guide as their primary learning tool.

  15. Thirty Years of Social Science Research on High-Level Nuclear Waste: Achievements and Future Challenges

    Research on high-level nuclear waste management has focused on technical and scientific issues since the U.S. National Academy of Sciences first studied the problem in the mid 1950s and recommended long-term disposal in deep salt formations. In this review, we trace the development of the problem's definition and its associated research since socioeconomic, political and policy issues were first given consideration and nuclear waste management became recognized as more than a technical issue. Three time periods are identified. First, from the mid 1970s to early 1980s, initial research explored institutional dimensions of nuclear waste, including ethics. The second period began in the early 1980s with a concerted effort to solve the problem and site nuclear waste repositories, and ended in the mid 1990s with minimal progress in the U.S. and general stalemate in Asia and Europe (with the notable exception of Sweden). This phase accelerated research on risk perception and stigma of nuclear waste, and elevated a focus on public trust. Great attention was given to repository siting conflicts, while minimal attention was placed on ethics, equity, political systems, and public participation. The last period, since the mid 1990s, has been characterized by continuing political stalemate and increased attention to public participation, political systems and international solutions. Questions of ethics have been given renewed attention, while research on risk perceptions and siting conflicts continues. We frame these periods in a broader context of the shifting role of applied social scientists. The paper concludes with a general discussion of this research area and prospects for future research

  16. Volumetric modulated arc therapy for lung stereotactic radiation therapy can achieve high local control rates

    The aim of this study was to report the outcome of primary or metastatic lung cancer patients undergoing volumetric modulated arc therapy for stereotactic body radiation therapy (VMAT-SBRT). From October 2010 to December 2013, consecutive 67 lung cancer patients received single-arc VMAT-SBRT using an Elekta-synergy system. All patients were treated with an abdominal compressor. The gross tumor volumes were contoured on 10 respiratory phases computed tomography (CT) datasets from 4-dimensional (4D) CT and merged into internal target volumes (ITVs). The planning target volume (PTV) margin was isotropically taken as 5 mm. Treatment was performed with a D95 prescription of 50 Gy (43 cases) or 55 Gy (12 cases) in 4 fractions for peripheral tumor or 56 Gy in 7 fractions (12 cases) for central tumor. Among the 67 patients, the median age was 73 years (range, 59–95 years). Of the patients, male was 72% and female 28%. The median Karnofsky performance status was 90-100% in 39 cases (58%) and 80-90% in 20 cases (30%). The median follow-up was 267 days (range, 40–1162 days). Tissue diagnosis was performed in 41 patients (61%). There were T1 primary lung tumor in 42 patients (T1a in 28 patients, T1b in 14 patients), T2 in 6 patients, three T3 in 3 patients, and metastatic lung tumor in 16 patients. The median mean lung dose was 6.87 Gy (range, 2.5-15 Gy). Six patients (9%) developed radiation pneumonitis required by steroid administration. Actuarial local control rate were 100% and 100% at 1 year, 92% and 75% at 2 years, and 92% and 75% at 3 years in primary and metastatic lung cancer, respectively (p = 0.59). Overall survival rate was 83% and 84% at 1 year, 76% and 53% at 2 years, and 46% and 20% at 3 years in primary and metastatic lung cancer, respectively (p = 0.12). Use of VMAT-based delivery of SBRT in primary in metastatic lung tumors demonstrates high local control rates and low risk of normal tissue complications

  17. Impact of Mindfulness-based Stress Reduction Training on Third Grade High School Female Students' Mental Health and Educational Achievement

    Gholamreza Sharifiniya

    2014-01-01

    Full Text Available This study is conducted with the title of "Impact of Mindfulness-Based Stress Reduction training on third grade high school female students' mental health and educational achievement in Asadabad city during the school year 2011-2012. This study aims at investigating the impact of Mindfulness-Based Stress Reduction (MBSR training on students' mental health and educational achievement. This research is conducted based on clinical trial with the empirical study (pretest-posttest method with the control group. Statistical population of this survey includes all third grade high school female students (780 students, who were educating in Asadabad city and the sample group contains 40 students ¬who were selected according to the randomized cluster method (20 subjects in the empirical group and 20 subjects in the control group. Data collection tool for mental health structure includes the components of interpersonal sensitivity, obsessive thoughts, depression, anxiety and somatization which are selected from the General Health Questionnaire (SCL-90. Results indicated that the Mindfulness-based stress reduction training has affected the components of obsessive thoughts, interpersonal sensitivity, depression and anxiety after 8 sessions, but it has no effect on the somatization. Furthermore, the mindfulness training also has a positive effect on the educational achievement.

  18. The effect of an integrated high school science curriculum on student achievement, knowledge retention, and science attitudes

    Smith, Kimberly A.

    The research study investigates the effectiveness of an integrated high school science curriculum on student achievement, knowledge retention and science attitudes using quantitative and qualitative research. Data was collected from tenth grade students, in a small urban high school in Kansas City, Missouri, who were enrolled in a traditional Biology course or an integrated Environmental Science course. Quantitative data was collected in Phase 1 of the study. Data collected for academic achievement included pretest and posttest scores on the CTBS MATN exam. Data collected for knowledge retention included post-posttest scores on the CTBS MATN exam. Data collected for science attitudes were scores on a pretest and posttest using the TOSRA. SPSS was used to analyze the data using independent samples t-tests, one-way ANCOVA's and paired samples statistics. Qualitative data was collected in Phase 2 of the study. Data included responses to open-ended interview questions using three focus groups. Data was analyzed for common themes. Data analysis revealed the integrated Environmental Science course had a statistically significant impact on academic achievement, knowledge retention and positive science attitudes. Gender and socioeconomic status did not influence results. The study also determined that the CTBS MATN exam was not an accurate predictor of scores on state testing as was previously thought.

  19. Relationships Among Student-body Composition, School Process, and Mathematics Achievement in Argentina’s High Schools

    Rubén Alberto Cervini Iturre

    2003-05-01

    Full Text Available This is a study of the relationships between the student-body composition of the school, some characteristics of the scholastic process—culture and school climate—according to learners’ perceptions, and the mathematics achievement of students in the last year of high school in Argentina. The data used came from the 1998 National Census of High School Completion, carried out by the nation’s Ministry of Culture and Education. The file contains data for 135,000 students of 2,708 schools in 25 states. Multilevel linear modeling with three levels (student, school and state was applied. A strong relationship was detected between mathematics achievement and the variables student-body composition and school process. When both variables acted together, the effect of other variables experienced a pronounced descent. Although reduced, the variables of the process influenced the student’s achievement. There was identified for future works a reference model which would evaluate other institutional learning factors.

  20. The relationship between service-learning participation and high school students' achievement in math and science education

    Elliott, Eddie Brown

    This study examined a causal relationship between service-learning participation and academic achievement of 9th grade students in math and science courses. The central purpose of the study was to examine the impact of service-learning participation on students' academic outcomes, and to determine if this impact was consistent after controlling for the socioeconomic status (SES) of the student. The participants in this study were from the base year data of the High School Longitudinal Study of 2009 (HSLS:09). For this study, 15,058 students identified as being enrolled in mathematics and science classes were selected. Quantitative methods were used to analyze cross-sectional data from the HSLS:09 study. The initial findings from this study suggest that service-learning participation was consistent in student's academic achievement of all students regardless of socioeconomic status.

  1. Control Method for Achieving High Power Factor in Single-Phase to Three-Phase Converters without Electrolytic Capacitors

    Yokoyama, Takahiro; Ohishi, Kiyoshi; Haga, Hitoshi; Shibata, Junji

    In this paper, we propose a method for the digital control of IPM motors in order to achieve a high power factor in single-phase to three-phase power converters without reactors or electrolytic capacitors. For achieving the unity power factor under any load condition and any speed condition, we propose a new digital control method that involves the use of a new feedback technique and a new feedforward technique on the source-current regulator side. The proposed digital control system is constructed by using DSP devices. In this paper, we also propose a new method for the compensation of one sampling delay time. The superior performance of the proposed method is demonstrated by experimental results. The experimental results were obtained using 1.5[kW] inverter system, which consists of a vector control system with a 14[μF] dc-link capacitor. The maximum power factor obtained in the experiments was 96.8[%].

  2. High Performing Schools in High Risk Environments: A Study on Leadership, School Safety, and Student Achievement at Two Urban Middle Schools in Los Angeles County

    Frias, Gus

    2010-01-01

    In the United States of America, all students and staff have a constitutional right to attend schools that are safe, secure, and successful. Despite this right, at many public schools, education leaders have failed to ensure the safety and high academic achievement of all students. The purpose of this research study is to expand knowledge about…

  3. A study on cultural practices for high forage yield in stylosanthes guianensis cv. Reyan No. 2%柱花草高产栽培综合农艺措施的研究

    戚春林; 胡耀华; 林日健

    2000-01-01

    试验采用5因素二次正交旋转组合回归设计,对柱花草高产栽培的综合农艺措施进行研究,并建立了干物质产量与种植密度、收割次数、施过磷酸钙量、施复合肥量、喷施钼酸铵浓度等5项农艺措施之间的数学模型,通过模型解析和寻优,得出在试验条件下,5项农艺措施对热研2号柱花草产量影响的程度依次为:收割次数>种植密度>施复合肥量>施过磷酸钙量>喷施钼酸铵浓度,并得出高产栽培组合方案.%Field test was conducted by quadratic orthogonal regression design. A regressive mode! Between the dry matter yield of Stylosanthes guianensis cv. Reyan No. 2 and cultural variables included plant density, cutting frequency, superphosphate application rates, compound fertilizer application rates and spraying concentration of ammonium molybdate was built. After analysis and optimization, it was concluded from the model that based on the extent of the effects of the variables on forae yields their order as follows: cutting frequency>plant density> compound fertilizer application rates>superphosphate application rates spraying concentration of ammonium molybdate. Cultural pratcices for high forage yield in S. Guianensis cv. Reyan No. 2 was recommended.

  4. Experimental Wing Damage Affects Foraging Effort and Foraging Distance in Honeybees Apis mellifera

    Andrew D. Higginson

    2011-01-01

    Full Text Available Bees acquire wing damage as they age, and loss of wing area affects longevity and behaviour. This may influence colony performance via effects on worker behaviour. The effects of experimental wing damage were studied in worker honeybees in observation hives by recording survivorship, how often and for how long bees foraged, and by decoding waggle dances. Mortality rate increased with both age and wing damage. Damaged bees carried out shorter and/or less frequent foraging trips, foraged closer to the hive, and reported the profitability of flower patches to be lower than did controls. These results suggest that wing damage caused a reduction in foraging ability, and that damaged bees adjusted their foraging behaviour accordingly. Furthermore, the results suggest that wing damage affects the profitability of nectar sources. These results have implications for the colony dynamics and foraging efficiency in honeybees.

  5. Contact rate modulates foraging efficiency in leaf cutting ants

    S. Bouchebti; Ferrere, S.; Vittori, K.; LATIL, G.; Dussutour, A; Fourcassié, V.

    2015-01-01

    Lane segregation is rarely observed in animals that move in bidirectional flows. Consequently, these animals generally experience a high rate of head-on collisions during their journeys. Although these collisions have a cost (each collision induces a delay resulting in a decrease of individual speed), they could also have a benefit by promoting information transfer between individuals. Here we explore the impact of head-on collisions in leaf-cutting ants moving on foraging trails by artificia...

  6. Similar Comparative Low and High Doses of Deltamethrin and Acetamiprid Differently Impair the Retrieval of the Proboscis Extension Reflex in the Forager Honey Bee (Apis mellifera

    Steeve H. Thany

    2015-09-01

    Full Text Available In the present study, the effects of low (10 ng/bee and high (100 ng/bee doses of acetamiprid and deltamethrin insecticides on multi-trial learning and retrieval were evaluated in the honey bee Apis mellifera. After oral application, acetamiprid and deltamethrin at the concentrations used were not able to impair learning sessions. When the retention tests were performed 1 h, 6 h, and 24 h after learning, we found a significant difference between bees after learning sessions when drugs were applied 24 h before learning. Deltamethrin-treated bees were found to be more sensitive at 10 ng/bee and 100 ng/bee doses compared to acetamiprid-treated bees, only with amounts of 100 ng/bee and at 6 h and 24 h delays. When insecticides were applied during learning sessions, none of the tested insecticides was able to impair learning performance at 10 ng/bee or 100 ng/bee but retention performance was altered 24 h after learning sessions. Acetamiprid was the only one to impair retrieval at 10 ng/bee, whereas at 100 ng/bee an impairment of retrieval was found with both insecticides. The present results therefore suggest that acetamiprid and deltamethrin are able to impair retrieval performance in the honey bee Apis mellifera.

  7. Space use and resource selection by foraging Indiana bats at the northern edge of their distribution

    Jachowski, David S.; Johnson, Joshua B.; Dobony, Christopher A.; Edwards, John W.; Ford, W. Mark

    2014-01-01

    Despite 4 decades of conservation concern, managing endangered Indiana bat (Myotis sodalis) populations remains a difficult wildlife resource issue facing natural resource managers in the eastern United States. After small signs of population recovery, the recent emergence of white-nose syndrome has led to concerns of local and/or regional extirpation of the species. Where Indiana bats persist, retaining high-quality foraging areas will be critical to meet physiological needs and ensure successful recruitment and overwinter survival. However, insight into foraging behavior has been lacking in the Northeast of the USA. We radio-tracked 12 Indiana bats over 2 summers at Fort Drum, New York, to evaluate factors influencing Indiana bat resource selection during night-time foraging. We found that foraging space use decreased 2% for every 100 m increase in distance to water and 6% for every 100 m away from the forest edge. This suggests high use of riparian areas in close proximity to forest and is somewhat consistent with the species’ foraging ecology in the Midwest and upper South. Given the importance of providing access to high-quality foraging areas during the summer maternity season, Indiana bat conservation at the northern extent of the species’ range will be linked to retention of forested habitat in close proximity to riparian zones. 

  8. Honey Bee Location- and Time-Linked Memory Use in Novel Foraging Situations: Floral Color Dependency

    Marisol Amaya-Márquez

    2014-02-01

    Full Text Available Learning facilitates behavioral plasticity, leading to higher success rates when foraging. However, memory is of decreasing value with changes brought about by moving to novel resource locations or activity at different times of the day. These premises suggest a foraging model with location- and time-linked memory. Thus, each problem is novel, and selection should favor a maximum likelihood approach to achieve energy maximization results. Alternatively, information is potentially always applicable. This premise suggests a different foraging model, one where initial decisions should be based on previous learning regardless of the foraging site or time. Under this second model, no problem is considered novel, and selection should favor a Bayesian or pseudo-Bayesian approach to achieve energy maximization results. We tested these two models by offering honey bees a learning situation at one location in the morning, where nectar rewards differed between flower colors, and examined their behavior at a second location in the afternoon where rewards did not differ between flower colors. Both blue-yellow and blue-white dimorphic flower patches were used. Information learned in the morning was clearly used in the afternoon at a new foraging site. Memory was not location-time restricted in terms of use when visiting either flower color dimorphism.

  9. A collimated focused ultrasound beam of high acoustic transmission and minimum diffraction achieved by using a lens with subwavelength structures

    Lin, Zhou; Tu, Juan; Cheng, Jianchun [Key Laboratory of Modern Acoustics (MOE), Department of Physics, Collaborative Innovation Center of Advanced Microstructure, Nanjing University, Nanjing 210093 (China); Guo, Xiasheng, E-mail: guoxs@nju.edu.cn, E-mail: dzhang@nju.edu.cn [Key Laboratory of Modern Acoustics (MOE), Department of Physics, Collaborative Innovation Center of Advanced Microstructure, Nanjing University, Nanjing 210093 (China); Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Wu, Junru [Department of Physics, University of Vermont, Burlington, Vermont 05405 (United States); Huang, Pingtong [Department of Ultrasound, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou 310009 (China); Zhang, Dong, E-mail: guoxs@nju.edu.cn, E-mail: dzhang@nju.edu.cn [Key Laboratory of Modern Acoustics (MOE), Department of Physics, Collaborative Innovation Center of Advanced Microstructure, Nanjing University, Nanjing 210093 (China); The State Key Laboratory of Acoustics, Chinese Academy of Science, Beijing 10080 (China)

    2015-09-14

    An acoustic focusing lens incorporated with periodically aligned subwavelength grooves corrugated on its spherical surface has been developed. It is demonstrated theoretically and experimentally that acoustic focusing achieved by using the lens can suppress the relative side-lobe amplitudes, enhance the focal gain, and minimize the shifting of the focus. Use of the lens coupled with a planar ultrasound transducer can generate an ultrasound beam with enhanced acoustic transmission and collimation effect, which offers the capability of improving the safety, efficiency, and accuracy of targeted surgery implemented by high intensity focused ultrasound.

  10. Association between scores in high school, aptitude and achievement exams and early performance in health science college

    Al-Alwan Ibrahim

    2009-01-01

    This retrospective study was carried out to assess the correlation between admi-ssion criteria to health science colleges, namely, final high school grade and Saudi National Apti-tude and Achievement exams, and early academic performance in these colleges. The study inclu-ded 91 male students studying in the two-year pre-professional program at the King Saud bin Abdulaziz University for Health Sciences (KSAU-HS), Riyadh, Saudi Arabia. Records of these students were used to extract relevant in...

  11. A collimated focused ultrasound beam of high acoustic transmission and minimum diffraction achieved by using a lens with subwavelength structures

    An acoustic focusing lens incorporated with periodically aligned subwavelength grooves corrugated on its spherical surface has been developed. It is demonstrated theoretically and experimentally that acoustic focusing achieved by using the lens can suppress the relative side-lobe amplitudes, enhance the focal gain, and minimize the shifting of the focus. Use of the lens coupled with a planar ultrasound transducer can generate an ultrasound beam with enhanced acoustic transmission and collimation effect, which offers the capability of improving the safety, efficiency, and accuracy of targeted surgery implemented by high intensity focused ultrasound

  12. Forage: a sensitive indicator of airborne radioactivity

    This paper presents the results of using Ge(Li) γ-ray spectroscopy to measure radioactivity concentration of forage in the vicinity of the Joseph M. Farley Nuclear Plant, Houston County, AL., over a 31/2 yr period. The report period includes 2 yr of pre-operational and 11/2 yr of operational sampling. Although the objective of forage sampling was the measurement of manmade airborne fallout radioactivity, several natural radioisotopes were also found to be present. A summary of natural radioactivity data for all samples measured during the period from August 1975 to December 1978 is given. Approximately 10 days after each of four Chinese atmospheric nuclear tests conducted during the sampling period fresh fission product fallout was measured on the forage. The information from these nuclear tests shows forage sampling to be a convenient and sensitive monitoring tool for airborne fallout radioactivity. (author)

  13. Contrasting responses of male and female foraging effort to year-round wind conditions.

    Lewis, Sue; Phillips, Richard A; Burthe, Sarah J; Wanless, Sarah; Daunt, Francis

    2015-11-01

    There is growing interest in the effects of wind on wild animals, given evidence that wind speeds are increasing and becoming more variable in some regions, particularly at temperate latitudes. Wind may alter movement patterns or foraging ability, with consequences for energy budgets and, ultimately, demographic rates. These effects are expected to vary among individuals due to intrinsic factors such as sex, age or feeding proficiency. Furthermore, this variation is predicted to become more marked as wind conditions deteriorate, which may have profound consequences for population dynamics as the climate changes. However, the interaction between wind and intrinsic effects has not been comprehensively tested. In many species, in particular those showing sexual size dimorphism, males and females vary in foraging performance. Here, we undertook year-round deployments of data loggers to test for interactions between sex and wind speed and direction on foraging effort in adult European shags Phalacrocorax aristotelis, a pursuit-diving seabird in which males are c. 18% heavier. We found that foraging time was lower at high wind speeds but higher during easterly (onshore) winds. Furthermore, there was an interaction between sex and wind conditions on foraging effort, such that females foraged for longer than males when winds were of greater strength (9% difference at high wind speeds vs. 1% at low wind speeds) and when winds were easterly compared with westerly (7% and 4% difference, respectively). The results supported our prediction that sex-specific differences in foraging effort would become more marked as wind conditions worsen. Since foraging time is linked to demographic rates in this species, our findings are likely to have important consequences for population dynamics by amplifying sex-specific differences in survival rates. PMID:26283625

  14. Sensory Ecology of Foraging in Bumblebees

    Spaethe, Johannes

    2002-01-01

    Pollinating insects exhibit a complex behavior while foraging for nectar and pollen. Many studies have focused on ultimate mechanisms of this behavior, however, the sensory-perceptual processes that constrain such behavior have rarely been considered. In the present study I used bumblebees (Bombus terrestris), an important pollinating insect, to investigate possible sensory constraints on foraging behavior. Additionally, I survey inter-individual variation in the sensory capabilities and beha...

  15. Interactions Increase Forager Availability and Activity in Harvester Ants.

    Evlyn Pless

    Full Text Available Social insect colonies use interactions among workers to regulate collective behavior. Harvester ant foragers interact in a chamber just inside the nest entrance, here called the 'entrance chamber'. Previous studies of the activation of foragers in red harvester ants show that an outgoing forager inside the nest experiences an increase in brief antennal contacts before it leaves the nest to forage. Here we compare the interaction rate experienced by foragers that left the nest and ants that did not. We found that ants in the entrance chamber that leave the nest to forage experienced more interactions than ants that descend to the deeper nest without foraging. Additionally, we found that the availability of foragers in the entrance chamber is associated with the rate of forager return. An increase in the rate of forager return leads to an increase in the rate at which ants descend to the deeper nest, which then stimulates more ants to ascend into the entrance chamber. Thus a higher rate of forager return leads to more available foragers in the entrance chamber. The highest density of interactions occurs near the nest entrance and the entrances of the tunnels from the entrance chamber to the deeper nest. Local interactions with returning foragers regulate both the activation of waiting foragers and the number of foragers available to be activated.

  16. Problem Solving Skills and Learning Achievements through Problem-Based Module in teaching and learning Biology in High School

    Wan Syafii

    2013-08-01

    Full Text Available The purpose of this study was to examine the effects of using problem-based module (PBM in the subject of Biology on high school students’ problem-solving skill and achievement. This research used the quasi-experiment method with Non-Equivalent Pretest and Posttest Control Group Design, which involved two science classes, in which one group was assigned as control group and another one as experiment group, in a high school in Pekan Baru, Indonesia. The problem-solving ability and the product of learning were descriptively analyzed before being inferentially analyzed. To find out whether or not there is any difference in their problem-solving skill, t-Test and N-gain test was conducted on the experimental group’s and control group’s concept mastery level and product of learning. The result shows that the problem-solving skill percentage of the experimental group was 95.47% (very good, whereas that of the control group was 25.12% (low. The average of student’s achievement in the experimental group was 84.26% (good, while that of the control group equaled 79.08% (moderate. The average of the product of learning was 89.89% (good for the experimental group, whereas that of the control group was 52.10% (low. The findings showed that PBM can actually increase problem-solving skill, students’ achievement, and students’ learning product, with the experimental group getting higher percentage in all three aspects compared to the control group by using PBM in their Biology class. The implication of this study is the increase in the quality of learning through learning innovation using learning module. The panned and organized implementation of this module by teachers will not only improve students’ thinking skills, but also increase the quality of science and technology, consistent with the aim of Indonesia education.

  17. Nutritional status, brain development and scholastic achievement of Chilean high-school graduates from high and low intellectual quotient and socio-economic status.

    Ivanovic, Daniza M; Leiva, Boris P; Pérez, Hernán T; Almagià, Atilio F; Toro, Triana D; Urrutia, MaríaSoledadC; Inzunza, Nélida B; Bosch, Enrique O

    2002-01-01

    The objective of the present study was to investigate the inter-relationships between nutritional status (past and current nutrition), brain development, and scholastic achievement (SA) of Chilean high-school graduates from high and low intellectual quotient (IQ) and socio-economic status (SES) (mean age 18.0 (SD 0.9) years). Results showed that independently of SES, high-school graduates with similar IQ have similar nutritional, brain development and SA variables. Multiple regression analysis between child IQ (dependent variable) and age, sex, SES, brain volume (BV), undernutrition during the first year of life, paternal and maternal IQ (independent variables) revealed that maternal IQ (Peducational planning. PMID:11895316

  18. 无意识成就目标对高低成就动机个体的激励%Effects of Unconscious Achievement Goals:When Individuals Are in High or Low Achievement Motivation

    陈瑞涵; 杨文静; 李海江; 张庆林

    2013-01-01

    The 2X2 mixed paradigm was used to investigate the effects of unconscious achievement goals on the outcome expectation and task performance of priming and non-priming in high and low achievement motivation individuals. The results showed that the priming effects of unconscious achievement goals were regulated by the level of the individuals' achievement motivation. Priming of unconscious achievement goals had no significant effects on the outcome expectation when the individuals were high on achievement motivation, but produced expectation of high outcome prior to working on the task when the individuals were low on achievement motivation. Priming of unconscious achievement goals had no significant effects on the task performance of the individuals with either high or low achievement motivation, and the individuals who scored high on achievement motivation got higher task performance whether the unconscious a-chievement goals were primed or not.%采用2×2混合实验设计探讨了在个体无意识状态下启动的成就目标,对高、低成就动机个体结果预期及任务表现的影响.研究结果表明无意识成就目标启动效应是否出现,受个体成就动机水平的调节:①无意识成就目标的启动,对高成就动机个体的结果预期没有显著影响,但是能显著提高低成就动机个体的结果预期;②无意识成就目标的启动,对高、低成就动机个体的任务表现均没有显著影响,但是高成就动机个体的任务表现显著好于低成就动机个体.

  19. Teaching image-processing concepts in junior high school: boys' and girls' achievements and attitudes towards technology

    Barak, Moshe; Asad, Khaled

    2012-04-01

    Background : This research focused on the development, implementation and evaluation of a course on image-processing principles aimed at middle-school students. Purpose : The overarching purpose of the study was that of integrating the learning of subjects in science, technology, engineering and mathematics (STEM), and linking the learning of these subjects to the children's world and to the digital culture characterizing society today. Sample : The participants were 60 junior high-school students (9th grade). Design and method : Data collection included observations in the classes, administering an attitude questionnaire before and after the course, giving an achievement exam and analyzing the students' final projects. Results and conclusions : The findings indicated that boys' and girls' achievements were similar throughout the course, and all managed to handle the mathematical knowledge without any particular difficulties. Learners' motivation to engage in the subject was high in the project-based learning part of the course in which they dealt, for instance, with editing their own pictures and experimenting with a facial recognition method. However, the students were less interested in learning the theory at the beginning of the course. The course increased the girls', more than the boys', interest in learning scientific-technological subjects in school, and the gender gap in this regard was bridged.

  20. Gender differences in Korean high school students’ science achievements and attitudes towards science in three different school settings

    EunJin Bang

    2013-08-01

    Full Text Available This study analysed the effect of high schools' gender organization on Korean tenth-grade students’ science achievements, and their attitudes towards science. The high schools involved included an all-male institution, an all-female institution, and a co-educational institution. Three schools, three principals, three science teachers, and 302 tenthgrade students from their respective school types responded to an initial survey, and eleven academically outstanding students were subsequently interviewed. Also, the students’ pencil and paper tests—which included second semester midterms, and final exams containing their general science test scoreswere collected from each school. The questionnaire responses and the transcribed interview sections were analysed using One-Way ANOVA, followed by Post Hoc analysis, constant comparison, and content analysis. Results indicated that the male and female students from the co-ed school had significantly higher science achievement and positive attitudes towards science. Interview transcripts of the selected students from the all-male, the all-female, and the co-ed schools confirmed the findings. Later discussion addresses the improvement of the Korean science curriculum, of learning environments, of the teachers’ and students' roles in the classroom, and of education policies.

  1. Wild chacma baboons (Papio ursinus) remember single foraging episodes.

    Noser, Rahel; Byrne, Richard W

    2015-07-01

    Understanding animal episodic-like memory is important for tracing the evolution of the human mind. However, our knowledge about the existence and nature of episodic-like memory in non-human primates is minimal. We observed the behaviour of a wild male chacma baboon faced with a trade-off between protecting his stationary group from aggressive extra-group males and foraging among five out-of-sight platforms. These contained high-priority food at a time of natural food shortage. In 10 morning and eight evening trials, the male spontaneously visited the platforms in five and four different sequences, respectively. In addition, he interrupted foraging sequences at virtually any point on eight occasions, returning to the group for up to 2 h. He then visited some or all of the remaining platforms and prevented revisits to already depleted ones, apparently based on his memory for the previous foraging episode about food value, location, and time. Efficient use of memory allowed him to keep minimal time absent from his group while keeping food intake high. These findings support the idea that episodic-like memory offers an all-purpose solution to a wide variety of problems that require flexible, quick, yet precise decisions in situations arising from competition for food and mates in wild primates. PMID:25833223

  2. Low forager fertility: demographic characteristic or methodological artifact?

    Early, J D

    1985-09-01

    Anthropological literature has long held that traditional foraging populations have low fertility levels. This research examines the number of live births per woman for 9 non-western forager groups who have been investigated in the last 20 years. Data are derived from 1) birth registration systems, 2) surveys conducted during short stays with the group, and 3) surveys conducted as part of longer ethnographic studies. Fertility rates for the groups are 1) 3.5 for the Kiunga area of Papula, New Guinea, 2) 4.2 for Northern Territory Australian aborigines, 3) 5.0 for Cayapo groups in Brazil, 4) 5.3 for Hiowe people of New Guinea, 5) 5.7 for 3 Xavante groups in Brazil, 6) 6.0 for West Alaskan Eskimos, 7) 6.9 for Nunamiut Eskimos of Alaska, 8) 7.6 for the Bisman-Asmat group of Indonesian New Guinea, and 9) 8.4 for the Winikina Warao of Venezuela. Since fertility rates are highest when ethnographic studies, which allow for question clarification, memory recall, and cross-checking, are used, the author believes that high fertility rates most accurately represent forager societies. Research on the Dobe ]Kung (fertility rate - 4.7), may contradict these findings, but the author believes that the ]Kung fertility rates are higher than reported because of infanticide practices, sexual abstinence during lactation, and disease related fertility problems. In summary, the study finds high fertility (7-9 births) in traditional foraging societies. Although the study examines small populations, correlation strength and overall consistency help verify the results. PMID:4077041

  3. Individual lifetime pollen and nectar foraging preferences in bumble bees

    Hagbery, Jessica; Nieh, James C.

    2012-10-01

    Foraging specialization plays an important role in the ability of social insects to efficiently allocate labor. However, relatively little is known about the degree to which individual bumble bees specialize on collecting nectar or pollen, when such preferences manifest, and if individuals can alter their foraging preferences in response to changes in the colony workforce. Using Bombus impatiens, we monitored all foraging visits made by every bee in multiple colonies and showed that individual foragers exhibit consistent lifetime foraging preferences. Based upon the distribution of foraging preferences, we defined three forager types (pollen specialists, nectar specialists, and generalists). In unmanipulated colonies, 16-36 % of individuals specialized (≥90 % of visits) on nectar or pollen only. On its first day of foraging, an individual's foraging choices (nectar only, pollen only, or nectar and pollen) significantly predicted its lifetime foraging preferences. Foragers that only collected pollen on their first day of foraging made 1.61- to 1.67-fold more lifetime pollen foraging visits (as a proportion of total trips) than foragers that only collected nectar on their first foraging day. Foragers were significantly larger than bees that stayed only in the nest. We also determined the effect of removing pollen specialists at early (brood present) or later (brood absent) stages in colony life. These results suggest that generalists can alter their foraging preferences in response to the loss of a small subset of foragers. Thus, bumble bees exhibit individual lifetime foraging preferences that are established early in life, but generalists may be able to adapt to colony needs.

  4. The effects of food abundance and disturbance on foraging flock patterns of the wintering Hooded Crane (Grus monacha)

    Ling Yang; Lizhi Zhou; and Yunwei Song

    2015-01-01

    Background:Food abundance and availability affect flock patterns of foraging birds. Cost and risk tradeoffs are especially critical for flocks of wintering waterbirds foraging in lake wetlands. Waterbirds losing suitable habitats face insufficient food supplies and high levels of disturbance, affecting their foraging activities. Our objective was to study the effects of food abundance and disturbances on flock size and the structure of Hooded Crane flocks wintering at Shengjin Lake and, as well, to understand the response of wintering waterbirds to habitat degradation for future management decisions and protection of the population. Methods:We investigated food abundance, disturbances and flock foraging activities of the wintering Hooded Crane in several foraging habitats of Shengjin Lake from November 2013 to April 2014. Flock size and structure were observed by scan sampling. Data on food abundance and disturbances were collected by sampling. Flock size and structure were compared among three wintering stages. The relationship between food resources, disturbances and flock size were illustrated using a generalized linear model. Results:In the early and middle wintering periods, the Hooded Crane used paddy fields as its major foraging habitat, where the number of foraging birds and flocks were the highest. During the late period, the cranes took to meadows as their major foraging habitat. The variation among foraging flock was mainly embodied in the size of the flocks, while the age composition of these flocks did not change perceptibly. Family flocks were notably different from flock groups in size and age composition. The results of a generalized linear model showed that the food abundance had a marked effect on foraging flock size and age composition, while disturbances had a significant effect only on flock size. From our analysis, it appeared that the combined effect of the two variables was significant on the size of the foraging flock, but had less impact

  5. Multimedia OC12 parallel interface using VCSEL array to achieve high-performance cost-effective optical interconnections

    Chang, Edward S.

    1996-09-01

    ribbon cable, and MT connectors to achieve a high-performance, low-cost parallel link. A logical model of a multimedia server with parallel connections to an ATM switch, and to clients is presented. The design of the parallel optical link is analyzed. Furthermore, the link configured for testing, the test method, and test results are presented to confirm the analysis and to assure reliable link performance.

  6. Nectar robbing, forager efficiency and seed set: Bumblebees foraging on the self incompatible plant Linaria vulgaris (Scrophulariaceae)

    Stout, Jane C.; Allen, John A.; Goulson, Dave

    2000-07-01

    In southern England, Linaria vulgaris (common yellow toadflax) suffers from high rates of nectar robbery by bumblebees. In a wild population of L. vulgaris we found that 96 % of open flowers were robbed. Five species of bumblebee were observed foraging on these flowers, although short-tongued species ( Bombus lapidarius, B. lucorum and B. terrestris) robbed nectar whilst longer-tongued ones behaved as legitimate pollinators ( B. hortorum and B. pascuorum). Nectar rewards were highly variable; on average there was less nectar in robbed than in unrobbed flowers, but this difference was not statistically significant. The proportion of flowers containing no nectar was significantly higher for robbed flowers compared with unrobbed flowers. Secondary robbers and legitimate pollinators had similar handling times on flowers and, assuming they select flowers at random to forage on, received approximately the same nectar profit per minute, largely because most flowers had been robbed. There was no significant difference in the number of seeds in pods of robbed flowers and in pods of flowers that were artificially protected against robbing. However, more of the robbed flowers set at least some seed than the unrobbed flowers, possibly as a consequence of the experimental manipulation. We suggest that nectar robbing has little effect on plant fecundity because legitimate foragers are present in the population, and that seed predation and seed abortion after fertilization may be more important factors in limiting seed production in this species.

  7. Availability and toxicity of cadmium to forage grasses grown in contaminated soil.

    Silva, Enilson B; Fonseca, Felipe G; Alleoni, Luís R F; Nascimento, Sandra S; Grazziotti, Paulo H; Nardis, Bárbara O

    2016-09-01

    It is important to know the mechanisms for forage development, especially those related to the tolerance of potentially toxic elements, when considering their use in phytoremediation in heavy metal contaminated areas. In this study, we evaluated plant growth, concentration, and the availability of cadmium (Cd) for forage grasses (Panicum maximum Jacq. cv. Aruana and cv. Tanzânia; Brachiaria decumbens cv. Basilisk; Brachiaria brizantha cv. Xaraés and cv. Marandu) cultivated in Cd contaminated soils. The experiments were performed under greenhouse conditions over a 90-day evaluation period, and the Cd rates were 2, 4, and 12 mg/kg of soil. The relative growth rate of the forage grasses decreased as Cd rates increased, and the following descending order of susceptibility was observed: Marandu > Xaraés > Aruana > Tanzânia > Basilisk, with regard to phytotoxicity in these plants. The forage Cd concentration increased in line with increases in the Cd rates. Cd contents extracted by Mehlich-1 and by diethylenetriaminepentaacetic acid presented high positive correlation with forage relative growth. The forage plants did not block Cd entry into the food chain because they were not capable of limiting Cd absorption. PMID:26854007

  8. Successful foraging zones of southern elephant seals from the Kerguelen Islands in relation to oceanographic conditions.

    Bailleul, Frédéric; Charrassin, Jean-Benoît; Monestiez, Pascal; Roquet, Fabien; Biuw, Martin; Guinet, Christophe

    2007-11-29

    Southern elephant seals, Mirounga leonina, undertake large-scale oceanic movements to access favourable foraging areas. Successful foraging areas of elephant seals from the Kerguelen Islands are investigated here in relation to oceanographic parameters. Movements and diving activity of the seals as well as oceanographic data were collected through a new generation of satellite relayed devices measuring and transmitting locations, pressure, temperature and salinity. For the first time, we have associated foraging behaviour, determined by high increased sinuosity in tracks, and dive density (i.e. number of dives performed per kilometre covered), and changes in body condition, determined by variations in drift rate obtained from drift dives, to identify the oceanographic conditions of successful foraging zones for this species. Two main sectors, one close to the Antarctic continent and the other along the Polar Front (PF), where both foraging activity and body condition increase, seem to be of particular interest for the seals. Within these regions, some seals tended to focus their foraging activity on zones with particular temperature signatures. Along the Antarctic continent, some seals targeted colder waters on the sea bottom during benthic dives, while at the PF the favourable zones tended to be warmer. The possible negative effect of colder waters in Antarctic on the swimming performances of potential fish or squid prey could explain the behaviour of elephant seals in these zones, while warmer waters within the PF could correspond to the optimal conditions for potential myctophid prey of elephant seals. PMID:17472917

  9. The effects of chlorpyrifos on cholinesterase activity and foraging behavior in the dragonfly, Anax junius (Odonata)

    Brewer, S.K.; Atchison, G.J.

    1999-01-01

    We examined head capsule cholinesterase (ChE) and foraging behavior in nymphs of the dragonfly, Anax junius, exposed for 24 h to 0.2, 0.6 and 1.0 ??g l-1 of the organophosphorus (OP) insecticide, chlorpyrifos [O,O-diethyl O-(3,5,6-trichloro-2-pyridyl) phosphorothioate]. The invertebrate community is an important component of the structure and function of wetland ecosystems, yet the potential effects of insecticides on wetland ecosystems are largely unknown. Our objectives were to determine if exposure to environmentally realistic concentrations of chlorpyrifos affected foraging behavior and ChE activity in head capsules of dragonfly nymphs. Nymphs were exposed to different concentrations of chlorpyrifos and different prey densities in a factorial design. ChE activities and foraging behaviors of treated nymphs were not statistically different (p ??? 0.05) from control groups. Prey density effects exerted a greater effect on dragonfly foraging than toxicant exposures. Nymphs offered higher prey densities exhibited more foraging behaviors but also missed their prey more often. High variability in ChE activities within the control group and across treated groups precluded determination of relationships between ChE and foraging behaviors. It appears that A. junius is relatively tolerant of chlorpyrifos, although the concentrations we tested have been shown in other work to adversely affect the prey base; therefore the introduction of this insecticide may have indirect adverse affects on top invertebrate predators such as Odonata.

  10. Spatio-Temporal Dynamics of Foraging Networks in the Grass-Cutting Ant Atta bisphaerica Forel, 1908 (Formicidae, Attini).

    Lopes, Juliane F S; Brugger, Mariana S; Menezes, Regys B; Camargo, Roberto S; Forti, Luiz Carlos; Fourcassié, Vincent

    2016-01-01

    Foraging networks are a key element for ant colonies because they facilitate the flow of resources from the environment to the nest and they allow the sharing of information among individuals. Here we report the results of an 8-month survey, extending from November 2009 to June 2010, of the foraging networks of four mature colonies of Atta bisphaerica, a species of grass-cutting ant which is considered as a pest in Brazil. We found that the distribution of foraging effort was strongly influenced by the landscape features around the nests, in particular by the permanently wet parts of the pasture in which the nests were located. The foraging networks consisted of underground tunnels which opened on average at 21.5m from the nests and of above-ground physical trails that reached on average 4.70m in length. The use of the foraging networks was highly dynamic, with few sections of the networks used for long periods of time. Three different phases, which could be linked to the seasonal change in the local rainfall regime, could be identified in the construction and use of the foraging networks. The first phase corresponded to the beginning of the rainy season and was characterized by a low foraging activity, as well as a low excavation and physical trail construction effort. The second phase, which began in February and extended up to the end of the humid season at the end of March, was characterized by an intense excavation and trail construction effort, resulting in an expansion of the foraging networks. Finally, in the third phase, which corresponded to the beginning of the dry season, the excavation and trail construction effort leveled off or decreased while foraging activity kept increasing. Our hypothesis is that ants could benefit from the underground tunnels and physical trails built during the humid season to maintain their foraging activity at a high level. PMID:26752413

  11. Spatio-Temporal Dynamics of Foraging Networks in the Grass-Cutting Ant Atta bisphaerica Forel, 1908 (Formicidae, Attini.

    Juliane F S Lopes

    Full Text Available Foraging networks are a key element for ant colonies because they facilitate the flow of resources from the environment to the nest and they allow the sharing of information among individuals. Here we report the results of an 8-month survey, extending from November 2009 to June 2010, of the foraging networks of four mature colonies of Atta bisphaerica, a species of grass-cutting ant which is considered as a pest in Brazil. We found that the distribution of foraging effort was strongly influenced by the landscape features around the nests, in particular by the permanently wet parts of the pasture in which the nests were located. The foraging networks consisted of underground tunnels which opened on average at 21.5m from the nests and of above-ground physical trails that reached on average 4.70m in length. The use of the foraging networks was highly dynamic, with few sections of the networks used for long periods of time. Three different phases, which could be linked to the seasonal change in the local rainfall regime, could be identified in the construction and use of the foraging networks. The first phase corresponded to the beginning of the rainy season and was characterized by a low foraging activity, as well as a low excavation and physical trail construction effort. The second phase, which began in February and extended up to the end of the humid season at the end of March, was characterized by an intense excavation and trail construction effort, resulting in an expansion of the foraging networks. Finally, in the third phase, which corresponded to the beginning of the dry season, the excavation and trail construction effort leveled off or decreased while foraging activity kept increasing. Our hypothesis is that ants could benefit from the underground tunnels and physical trails built during the humid season to maintain their foraging activity at a high level.

  12. Interviews with Students of High Confidence and Low Achievement. Mathematics Education Diagnostic and Instructional Centre (MEDIC) Report No. 5-76.

    Feghali, Issa

    A previous study had confirmed that a substantial number of low achievers in grades 5 through 8 had high algorithmic confidence in each of the four arithmetic operations with whole numbers. The purpose of the present study was to follow up the results through interviewing low achievement-high confidence students in order to ascertain if they…

  13. 2009 Winter Forage Conference to teach horse owners about forage and grazing management

    Sutphin, Michael D.

    2009-01-01

    Virginia Cooperative Extension and the Virginia Forage and Grassland Council will explore how horse owners can best utilize their land for grazing and protect soil and water resources at the same time during this year's equine forage conference on March 2 through 4.

  14. Beneficial Effects of Temperate Forage Legumes that Contain Condensed Tannins

    Jennifer W. MacAdam

    2015-07-01

    Full Text Available The two temperate forage legumes containing condensed tannins (CT that promote ruminant production are birdsfoot trefoil (Lotus corniculatus L.; BFT and sainfoin (Onobrychis viciifolia Scop.; SF. Both are well-adapted to the cool-temperate climate and alkaline soils of the Mountain West USA. Condensed tannins comprise a diverse family of bioactive chemicals with multiple beneficial functions for ruminants, including suppression of internal parasites and enteric methane. Birdsfoot trefoil contains 10 to 40 g·CT·kg−1 dry matter (DM, while SF contains 30 to 80 g·CT·kg−1 DM. Our studies have focused on these two plant species and have demonstrated consistently elevated rates of gain for beef calves grazing both BFT and SF. Novel results from our BFT research include carcass dressing percentages and consumer sensory evaluations equivalent to feedlot-finished steers and significantly greater than grass-finished steers, but with omega-3 fatty acid concentrations equal to grass-finished beef. We have further demonstrated that ruminants fed BFT or SF will consume more endophyte-infected tall fescue (Schedonorus arundinaceus (Schreb. Dumort. forage or seed than ruminants fed a non-CT forage legume. There is great potential value for sustainable livestock production in the use of highly digestible, nitrogen-fixing legumes containing tannins demonstrated to improve ruminant productivity.

  15. Therapeutic Potential of Temperate Forage Legumes: A Review.

    Cornara, Laura; Xiao, Jianbo; Burlando, Bruno

    2016-07-29

    The discovery of bioactive molecules from botanical sources is an expanding field, preferentially oriented to plants having a tradition of use in medicine and providing high yields and availability. Temperate forage legumes are Fabaceae species that include worldwide-important crops. These plants possess therapeutic virtues that have not only been used in veterinary and folk medicine, but have also attracted the interest of official medicine. We have examined here Medicago sativa (alfalfa), Trifolium pratense and T. repens (clovers), Melilotus albus and M. officinalis (sweet clovers), Lotus corniculatus (birdsfoot trefoil), Onobrychis viciifolia (sainfoin), Lespedeza capitata (roundhead lespedeza), and Galega officinalis (goat's rue). The phytochemical complexes of these species contain secondary metabolites whose pharmacological potentials deserve investigation. Major classes of compounds include alkaloids and amines, cyanogenic glycosides, flavonoids, coumarins, condensed tannins, and saponins. Some of these phytochemicals have been related to antihypercholesterolemia, antidiabetic, antimenopause, anti-inflammatory, antiedema, anthelmintic, and kidney protective effects. Two widely prescribed drugs have been developed starting from temperate forage legumes, namely, the antithrombotic warfarin, inspired from sweet clover's coumarin, and the antidiabetic metformin, a derivative of sainfoin's guanidine. Available evidence suggests that temperate forage legumes are a potentially important resource for the extraction of active principles to be used as nutraceuticals and pharmaceuticals. PMID:26507574

  16. Competition and facilitation between a native and a domestic herbivore: trade-offs between forage quantity and quality.

    Augustine, David J; Springer, Tim L

    2013-06-01

    Potential competition between native and domestic herbivores is a major consideration influencing the management and conservation of native herbivores in rangeland ecosystems. In grasslands of the North American Great Plains, black-tailed prairie dogs (Cynomys ludovicianus) are widely viewed as competitors with cattle but are also important for biodiversity conservation due to their role in creating habitat for other native species. We examined spatiotemporal variation in prairie dog effects on growing-season forage quality and quantity using measurements from three colony complexes in Colorado and South Dakota and from a previous study of a fourth complex in Montana. At two complexes experiencing below-average precipitation, forage availability both on and off colonies was so low (12-54 g/m2) that daily forage intake rates of cattle were likely constrained by instantaneous intake rates and daily foraging time. Under these dry conditions, prairie dogs (1) substantially reduced forage availability, thus further limiting cattle daily intake rates, and (2) had either no or a small positive effect on forage digestibility. Under such conditions, prairie dogs are likely to compete with cattle in direct proportion to their abundance. For two complexes experiencing above-average precipitation, forage quantity on and off colonies (77-208 g/m2) was sufficient for daily forage intake of cattle to be limited by digestion rather than instantaneous forage intake. At one complex where prairie dogs enhanced forage digestibility and [N] while having no effect on forage quantity, prairie dogs are predicted to facilitate cattle mass gains regardless of prairie dog abundance. At the second complex where prairie dogs enhanced digestibility and [N] but reduced forage quantity, effects on cattle can vary from competition to facilitation depending on prairie dog abundance. Our findings show that the high spatiotemporal variation in vegetation dynamics characteristic of semiarid grasslands

  17. Functional Organosulfide Electrolyte Promotes an Alternate Reaction Pathway to Achieve High Performance in Lithium-Sulfur Batteries.

    Chen, Shuru; Dai, Fang; Gordin, Mikhail L; Yu, Zhaoxin; Gao, Yue; Song, Jiangxuan; Wang, Donghai

    2016-03-18

    Lithium-sulfur (Li-S) batteries have recently received great attention because they promise to provide energy density far beyond current lithium ion batteries. Typically, Li-S batteries operate by conversion of sulfur to reversibly form different soluble lithium polysulfide intermediates and insoluble lithium sulfides through multistep redox reactions. Herein, we report a functional electrolyte system incorporating dimethyl disulfide as a co-solvent that enables a new electrochemical reduction pathway for sulfur cathodes. This pathway uses soluble dimethyl polysulfides and lithium organosulfides as intermediates and products, which can boost cell capacity and lead to improved discharge-charge reversibility and cycling performance of sulfur cathodes. This electrolyte system can potentially enable Li-S batteries to achieve high energy density. PMID:26918660

  18. Real-time visual sensing system achieving high-speed 3D particle tracking with nanometer resolution.

    Cheng, Peng; Jhiang, Sissy M; Menq, Chia-Hsiang

    2013-11-01

    This paper presents a real-time visual sensing system, which is created to achieve high-speed three-dimensional (3D) motion tracking of microscopic spherical particles in aqueous solutions with nanometer resolution. The system comprises a complementary metal-oxide-semiconductor (CMOS) camera, a field programmable gate array (FPGA), and real-time image processing programs. The CMOS camera has high photosensitivity and superior SNR. It acquires images of 128×120 pixels at a frame rate of up to 10,000 frames per second (fps) under the white light illumination from a standard 100 W halogen lamp. The real-time image stream is downloaded from the camera directly to the FPGA, wherein a 3D particle-tracking algorithm is implemented to calculate the 3D positions of the target particle in real time. Two important objectives, i.e., real-time estimation of the 3D position matches the maximum frame rate of the camera and the timing of the output data stream of the system is precisely controlled, are achieved. Two sets of experiments were conducted to demonstrate the performance of the system. First, the visual sensing system was used to track the motion of a 2 μm polystyrene bead, whose motion was controlled by a three-axis piezo motion stage. The ability to track long-range motion with nanometer resolution in all three axes is demonstrated. Second, it was used to measure the Brownian motion of the 2 μm polystyrene bead, which was stabilized in aqueous solution by a laser trapping system. PMID:24216655

  19. Forage and seed production of Puero (Pueraria javanica in a Different Light intensity level

    Fanindi A

    2016-06-01

    Full Text Available Puero (Pueraria javanica is forage that can serve as a cover crop in plantations. The limiting factor for plant growth in the plantation is the light intensity, therefore the influence of light intensity on forage and seed production of Puero needs to be examined. Research was conducted at Kaum Pandak Research station of Indonesian Research Institute for Animal Production Bogor and Laboratory of Agrostology Faculty of Animal Husbandry, Bogor Agricultural University, for 16 months. Four levels of light intensity,i.e 100, 80,60 and 40% were applied, leguminosainous species Puero (Pueraria javanica, was used. The treatments were arangged in Randomized Complete Block Design with 3 replications. Data collected were analyzed by ANOVA and Duncan’s Multiple Range Test. Forage production was evaluated in one year. The forage quality and digestibility (invitro were assessed. Seed production was recorded accumulatively from seasonal seed production during one year. Results show that light intensity affected (P 0.05 quality and digestibility of Puero. The highest forage and seed production of Puero were obtained from full light intensity (100%. and seed production of Puero was affected (P < 0.05 by light intensity. The seed quality of Puero was also affected by light intensity. The best seed quality of Puero was achieved by from 80% light intensity.

  20. Black Phosphorus Based Field Effect Transistors with Simultaneously Achieved Near Ideal Subthreshold Swing and High Hole Mobility at Room Temperature.

    Liu, Xinke; Ang, Kah-Wee; Yu, Wenjie; He, Jiazhu; Feng, Xuewei; Liu, Qiang; Jiang, He; Dan Tang; Wen, Jiao; Lu, Youming; Liu, Wenjun; Cao, Peijiang; Han, Shun; Wu, Jing; Liu, Wenjun; Wang, Xi; Zhu, Deliang; He, Zhubing

    2016-01-01

    Black phosphorus (BP) has emerged as a promising two-dimensional (2D) material for next generation transistor applications due to its superior carrier transport properties. Among other issues, achieving reduced subthreshold swing and enhanced hole mobility simultaneously remains a challenge which requires careful optimization of the BP/gate oxide interface. Here, we report the realization of high performance BP transistors integrated with HfO2 high-k gate dielectric using a low temperature CMOS process. The fabricated devices were shown to demonstrate a near ideal subthreshold swing (SS) of ~69 mV/dec and a room temperature hole mobility of exceeding >400 cm(2)/Vs. These figure-of-merits are benchmarked to be the best-of-its-kind, which outperform previously reported BP transistors realized on traditional SiO2 gate dielectric. X-ray photoelectron spectroscopy (XPS) analysis further reveals the evidence of a more chemically stable BP when formed on HfO2 high-k as opposed to SiO2, which gives rise to a better interface quality that accounts for the SS and hole mobility improvement. These results unveil the potential of black phosphorus as an emerging channel material for future nanoelectronic device applications. PMID:27102711

  1. Black Phosphorus Based Field Effect Transistors with Simultaneously Achieved Near Ideal Subthreshold Swing and High Hole Mobility at Room Temperature

    Liu, Xinke; Ang, Kah-Wee; Yu, Wenjie; He, Jiazhu; Feng, Xuewei; Liu, Qiang; Jiang, He; Dan Tang; Wen, Jiao; Lu, Youming; Liu, Wenjun; Cao, Peijiang; Han, Shun; Wu, Jing; Liu, Wenjun; Wang, Xi; Zhu, Deliang; He, Zhubing

    2016-04-01

    Black phosphorus (BP) has emerged as a promising two-dimensional (2D) material for next generation transistor applications due to its superior carrier transport properties. Among other issues, achieving reduced subthreshold swing and enhanced hole mobility simultaneously remains a challenge which requires careful optimization of the BP/gate oxide interface. Here, we report the realization of high performance BP transistors integrated with HfO2 high-k gate dielectric using a low temperature CMOS process. The fabricated devices were shown to demonstrate a near ideal subthreshold swing (SS) of ~69 mV/dec and a room temperature hole mobility of exceeding >400 cm2/Vs. These figure-of-merits are benchmarked to be the best-of-its-kind, which outperform previously reported BP transistors realized on traditional SiO2 gate dielectric. X-ray photoelectron spectroscopy (XPS) analysis further reveals the evidence of a more chemically stable BP when formed on HfO2 high-k as opposed to SiO2, which gives rise to a better interface quality that accounts for the SS and hole mobility improvement. These results unveil the potential of black phosphorus as an emerging channel material for future nanoelectronic device applications.

  2. Modality-specific attention in foraging bumblebees.

    Nityananda, Vivek; Chittka, Lars

    2015-10-01

    Attentional demands can prevent humans and other animals from performing multiple tasks simultaneously. Some studies, however, show that tasks presented in different sensory modalities (e.g. visual and auditory) can be processed simultaneously. This suggests that, at least in these cases, attention might be modality-specific and divided differently between tasks when present in the same modality compared with different modalities. We investigated this possibility in bumblebees (Bombus terrestris) using a biologically relevant experimental set-up where they had to simultaneously choose more rewarding flowers and avoid simulated predatory attacks by robotic 'spiders'. We found that when the tasks had to be performed using visual cues alone, bees failed to perform both tasks simultaneously. However, when highly rewarding flowers were indicated by olfactory cues and predators were indicated by visual cues, bees managed to perform both tasks successfully. Our results thus provide evidence for modality-specific attention in foraging bees and establish a novel framework for future studies of crossmodal attention in ecologically realistic settings. PMID:26587245

  3. Attributes and characteristics of the Mathematics, Engineering, Science, Achievement (MESA) high school program for first-generation Latino students

    Flores, Ramon

    This study used a web-based survey collected data from 28 first-generation Latino engineers who participated in the Mathematics, Engineering, Science, Achievement (MESA) program during their high school years. From the set of 28 respondents, 5 volunteered to participate in an optional telephone interview. The purpose of this study was to describe the critical attributes and characteristics of the MESA program that lead to success at both the high school and college levels for first-generation Latino students. Success at the high school level was operationally defined as successfully graduating with a high school diploma. Success at the college level was operationally defined here as college graduation with an engineering degree. Using a mixed-methods technique, the researcher attempted to secure consensus of opinion from a sample population of 28 first-generation Latino engineers. The mixed-methods technique was chosen since it allowed the researcher to draw on the strengths of quantitative and qualitative approaches. According to the findings, the typical respondent felt that mentoring was the attribute of the MESA program that most prepared him to graduate from high school. The respondents felt that the following MESA attributes most helped them transition into an undergraduate engineering program: Academic and University Advising; Enrichment Activities; Career Advising; Field Trips; Mentoring; Scholarship Incentive Awards; and Speakers. The respondents viewed study groups as the MESA attribute that best prepared them to graduate college with an engineering degree. This study was purposefully designed as a descriptive study. Future research is required to extend this work into an evaluative study. This would allow for the generalization of the critical attributes to the general student population serviced by the MESA program.

  4. Foraging ecology of sanderlings Calidris alba wintering in estuarine and non-estuarine intertidal areas

    Lourenço, Pedro M.; Alves, José A.; Catry, Teresa; Granadeiro, José P.

    2015-10-01

    Outside the breeding season, most shorebirds use either estuarine or non-estuarine intertidal areas as foraging grounds. The sanderling Calidris alba is mostly associated with coastal sandy beaches, a habitat which is currently at risk worldwide due to increasing coastal erosion, but may also use estuarine sites as alternative foraging areas. We aimed to compare the trophic conditions for sanderlings wintering in estuarine and non-estuarine sites within and around the Tejo estuary, Portugal, where these two alternative wintering options are available within a relatively small spatial scale. To achieve this, we analysed sanderling diet, prey availability, foraging behaviour, and time and energy budgets in the different substrates available in estuarine and non-estuarine sites. In terms of biomass, the most important sanderling prey in the estuarine sites were siphons of the bivalve Scrobicularia plana, polychaetes, staphylinids and the gastropod Hydrobia ulvae. In non-estuarine sites the main prey were polychaetes, the bivalve Donax trunculus and chironomid larvae. Both food availability and energetic intake rates were higher on estuarine sites, and sanderlings spent a higher proportion of time foraging on non-estuarine sites. In the estuary, sanderlings foraged in muddy-sand substrate whenever it was available, achieving higher intake rates than in sandy substrates. In the non-estuarine sites they used both sandy and rocky substrates throughout the tidal cycle but had higher intakes rates in sandy substrate. Estuarine sites seem to offer better foraging conditions for wintering sanderlings than non-estuarine sites. However, sanderlings only use muddy-sand and sandy substrates, which represent a small proportion of the intertidal area of the estuary. The extent of these substrates and the current sanderling density in the estuary suggest it is unlikely that the estuary could provide alternative wintering habitat for sanderlings if they face habitat loss and

  5. Evolution of foraging behavior in Drosophilid larvae

    Rivera-Alba, Marta; Kabra, Mayank; Branson, Kristin; Mirth, Christen

    2015-03-01

    Drosophilids, like other insects, go through a larval phase before metamorphosing into adults. Larvae increase their body weight by several orders of magnitude in a few days. We therefore hypothesized that foraging behavior is under strong evolutionary pressure to best fit the larval environment. To test our hypothesis we used a multidisciplinary approach to analyze foraging behavior across species and larval stages. First, we recorded several videos of larvae foraging for each of 47 Drosophilid species. Then, using a supervised machine learning approach, we automatically annotated the video collection for the foraging sub-behaviors, including crawling, turning, head casting or burrowing. We also computed over 100 features to describe the posture and dynamics of each animal in each video frame. From these data, we fit models to the behavior of each species. The models each had the same parametric form, but differed in the exact parameters. By simulating larva behavior in virtual arenas we can infer which properties of the environments are better for each species. Comparisons between these inferred environments and the actual environments where these animals live will give us a deeper understanding about the evolution of foraging behavior in Drosophilid larvae.

  6. Utilisation des polymères organiques durant le forage et la cimentation des puits à haute température Using Organic Polymers During Drilling and Cementing of High Temperature Wells

    Martin M.

    2006-11-01

    Full Text Available Dans les puits pétroliers, par suite de l'accroissement de la profondeur, des températures statiques de fond voisines de 250 °C seront probablement atteintes dans un très proche avenir. Dans les puits géothermiques à haute énergie, cette limite est déjà largement dépassée avec des températures pouvant aller jusque 400 °C. II est indispensable que les fluides de forage et les matériaux de cimentation alors mis en oeuvre possèdent des stabilités suffisantes. Pour les fluides de forage, à base d'eau et à base d'huile, il convient de prévenir, à l'aide d'additifs, les évolutions réversibles et irréversibles des caractéristiques de viscosité et de filtration durant le cycle ou pendant des arrêts de circulation de quelques heures. Ces additifs sont, pour la plupart, des polymères susceptibles de se disperser dans la phase liquide. Mais actuellement leur stabilité ne permet guère d'envisager l'utilisation des fluides à base d'eau au-delà de 260 °C et celle des fluides à base d'huile au-delà de 285 °C. Pour les cimentations, il peut être souhaitable de remplacer le ciment hydraulique habituellement employé par un matériau de masse volumique plus faible et/ou de durabilité accrue. Pendant toute la vie du puits, prévue pour 20 à 30 ans, ce matériau devra assurer l'étanchéité de l'annulaire et conserver sa résistance mécanique. II devra, de plus, supporter l'environnement parfois agressif des eaux de formation. Des recherches de laboratoire sur de nouveaux matériaux de cimentation ont été orientées vers des résines organiques et des composés à base d'organosiloxanes. Elles conduisent à sélectionner des formules stables jusqu'à 300 °C. Mais les possibilités de mise en oeuvre sur puits restent encore à étudier et le coût élevé des produits de base risque de limiter leur application. Static downhole temperatures of around 250°C will probably be reached in the very near future in oil wells as the

  7. Offering a forage crop at pasture did not adversely affect voluntary cow traffic or milking visits in a pasture-based automatic milking system.

    Scott, V E; Kerrisk, K L; Garcia, S C

    2016-03-01

    Feed is a strong incentive for encouraging cows in automatic milking systems (AMS) to voluntarily move around the farm and achieve milkings distributed across the 24 h day. It has been reported that cows show preferences for some forages over others, and it is possible that offering preferred forages may increase cow traffic. A preliminary investigation was conducted to determine the effect of offering a forage crop for grazing on premilking voluntary waiting times in a pasture-based robotic rotary system. Cows were offered one of two treatments (SOYBEAN or GRASS) in a cross-over design. A restricted maximum likelihood procedure was used to model voluntary waiting times. Mean voluntary waiting time was 45.5±6.0 min, with no difference detected between treatments. High and mid-production cows spent 55 min/milking for low-production cows, whereas waiting time increased as queue length increased. Voluntary waiting time was 23% and 80% longer when cows were fetched from the paddock or had a period of forced waiting before volunteering for milking, respectively. The time it took cows to return to the dairy since last exiting was not affected by treatment, with a mean return time of 13.7±0.6 h. Although offering SOYBEAN did not encourage cows to traffic more readily through the premilking yard, the concept of incorporating forage crops in AMS still remains encouraging if the aim is to increase the volume or quantity of home-grown feed rather than improving cow traffic. PMID:26567465

  8. Reindeer (Rangifer tarandus and climate change: Importance of winter forage

    Thrine Moen Heggberget

    2002-06-01

    climate may cause an altitudinal upward shift in the production of mat-forming lichens in alpine, sub-arctic regions. This is due to an increased potential for lichen growth at high altitudes, combined with increased competition from taller-growing vascular plants at lower altitudes, where the biomass of Betula nana in particular will increase. Matforming lichens dominant on dry, windblown ridges are easily overgrazed at high reindeer densities. This has longterm effects due to lichens’ slow regeneration rate, but may also reduce competition from vascular plants in a long time perspective. Fires may act in a similar way in some forested areas. Accessibility of winter forage depends on plant biomass, snow depth and hardness; ice crusts or exceptionally deep snow may result in starvation and increased animal mortality. Calf recruitment appears to be low and/or highly variable where winter ranges are overgrazed and hard or deep snow is common. Population decline in several Rangifer tarandus spp. has been associated with snow-rich winters. Effects tend to be delayed and cumulative, particularly on calves. This is mainly ascribed to feeding conditions for young animals which later affect age at maturation. Global warming may increase the frequency of deep or hard snow on reindeer ranges in Norway, due to increased precipitation and more frequent mild periods in winter. We hypothesise that potential benefits from increased plant productivity due to global warming will be counteracted by shifts in the distribution of preferred lichen forage, reduction of the areas of suitable winter ranges, and generally reduced forage accessibility in winter.

  9. Progress achieved in restricting the marketing of high-fat, sugary and salty food and beverage products to children.

    Kraak, Vivica I; Vandevijvere, Stefanie; Sacks, Gary; Brinsden, Hannah; Hawkes, Corinna; Barquera, Simón; Lobstein, Tim; Swinburn, Boyd A

    2016-07-01

    In May 2010, 192 Member States endorsed Resolution WHA63.14 to restrict the marketing of food and non-alcoholic beverage products high in saturated fats, trans fatty acids, free sugars and/or salt to children and adolescents globally. We examined the actions taken between 2010 and early 2016 - by civil society groups, the World Health Organization (WHO) and its regional offices, other United Nations (UN) organizations, philanthropic institutions and transnational industries - to help decrease the prevalence of obesity and diet-related noncommunicable diseases among young people. By providing relevant technical and policy guidance and tools to Member States, WHO and other UN organizations have helped protect young people from the marketing of branded food and beverage products that are high in fat, sugar and/or salt. The progress achieved by the other actors we investigated appears variable and generally less robust. We suggest that the progress being made towards the full implementation of Resolution WHA63.14 would be accelerated by further restrictions on the marketing of unhealthy food and beverage products and by investing in the promotion of nutrient-dense products. This should help young people meet government-recommended dietary targets. Any effective strategies and actions should align with the goal of WHO to reduce premature mortality from noncommunicable diseases by 25% by 2025 and the aim of the UN to ensure healthy lives for all by 2030. PMID:27429493

  10. A method for achieving monotonic frequency-temperature response for langasite surface-acoustic-wave high-temperature sensor

    Shaoming, Bao; Yabing, Ke; Yanqing, Zheng; Lina, Cheng; Honglang, Li

    2016-02-01

    To achieve the monotonic frequency-temperature response for a high-temperature langasite (LGS) surface-acoustic-wave (SAW) sensor in a wide temperature range, a method utilizing two substrate cuts with different propagation angles on the same substrate plane was proposed. In this method, the theory of effective permittivity is adopted to calculate the temperature coefficients of frequency (TCF), electromechanical coupling coefficients (k2), and power flow angle (PFA) for different propagation angles on the same substrate plane, and then the two substrate cuts were chosen to have large k2 and small PFA, as well as the difference in their TCFs (ΔTCF) to always have the same sign of their values. The Z-cut LGS substrate plane was taken as an example, and the two suitable substrate cuts with propagation angles of 74 and 80° were chosen to derive a monotonic frequency-temperature response for LGS SAW sensors at -50 to 540 °C. Experiments on a LGS SAW sensor using the above two substrate cuts were designed, and its measured frequency-temperature response at -50 to 540 °C agreed well with the theory, demonstrating the high accuracy of the proposed method.

  11. A methodology for achieving high-speed rates for artificial conductance injection in electrically excitable biological cells.

    Butera, R J; Wilson, C G; Delnegro, C A; Smith, J C

    2001-12-01

    We present a novel approach to implementing the dynamic-clamp protocol (Sharp et al., 1993), commonly used in neurophysiology and cardiac electrophysiology experiments. Our approach is based on real-time extensions to the Linux operating system. Conventional PC-based approaches have typically utilized single-cycle computational rates of 10 kHz or slower. In thispaper, we demonstrate reliable cycle-to-cycle rates as fast as 50 kHz. Our system, which we call model reference current injection (MRCI); pronounced merci is also capable of episodic logging of internal state variables and interactive manipulation of model parameters. The limiting factor in achieving high speeds was not processor speed or model complexity, but cycle jitter inherent in the CPU/motherboard performance. We demonstrate these high speeds and flexibility with two examples: 1) adding action-potential ionic currents to a mammalian neuron under whole-cell patch-clamp and 2) altering a cell's intrinsic dynamics via MRCI while simultaneously coupling it via artificial synapses to an internal computational model cell. These higher rates greatly extend the applicability of this technique to the study of fast electrophysiological currents such fast a currents and fast excitatory/inhibitory synapses. PMID:11759927

  12. Elimination of perinatal HIV infection in the United States and other high-income countries: achievements and challenges

    Nesheim, Steven; Harris, Lauren Fitz; Lampe, Margaret

    2015-01-01

    Purpose of review To describe progress and challenges to elimination of mother-to-child HIV transmission (EMCT) in high-income countries. Recent findings Despite ongoing declines in the number of perinatally HIV-infected infants in most high-income countries, the number of HIV-infected women delivering may be increasing, accompanied by apparent changes in this population, including higher percentages with antiretroviral “pre-treatment” (with possible antiretroviral resistance), other co-infections, mental health diagnoses, and recent immigration. The impact of antiretroviral resistance on mother-to-child transmission is yet to be defined. A substantial minority of infant HIV acquisitions occur in the context of maternal acute HIV infection during pregnancy. Some infant infections occur after pregnancy, e.g., by premastication of food, or breastfeeding (perhaps by an uninfected woman who acquires HIV while breastfeeding). Summary The issues of EMCT are largely those of providing proper care for HIV-infected women. Use of combination antiretroviral therapy by increasing proportions of the infected population may function as a structural intervention important to achieving this goal. Providers and public health systems need to be alert for HIV-serodiscordant couples in which the woman is uninfected and for changes in the population of HIV-infected pregnant women. Accurate data about HIV-exposed pregnancies is vital to monitor progress toward EMCT. PMID:23925002

  13. The preclinical set-up at the ID17 biomedical beamline to achieve high local dose deposition using interlaced microbeams

    Bräuer-Krisch, E.; Nemoz, C.; Brochard, Th; Berruyer, G.; Renier, M.; Pouyatos, B.; Serduc, R.

    2013-03-01

    Microbeam Radiation Therapy (MRT) uses spatially a fractionated "white beam" (energies 50-350 keV) irradiation from a Synchrotron Source. The typical microbeams used at ID17 are 25-100μm-thick, spaced by 200-400μm, and carry extremely high dose rates (up to about 16 kGy/s). These microbeams are well tolerated by biological tissue, i.e. up to several hundred of Gy in the peaks. When valley doses, caused by Compton scattering in between two microbeams, remain within a dose regime similar to conventional RT, a superior tumour control can be achieved with MRT than with conventional RT. The normal tissue tolerance of these microscopically small beams is outstanding and well documented in the literature. The hypothesis of a differential effect in particular on the vasculature of normal versus tumoral tissue might best be proven by using large animal models with spontaneous tumors instead of small laboratory animals with transplantable tumors, an ongoing project on ID17. An alternative approach to deposit a high dose, while preserving the feature of the spatial separation of these microbeams outside the target has opened up new applications in preclinical research. The instrumentation of this method to produce such interlaced beams is presented with an outlook on the challenges to build a treatment platform for human patients. Dose measurements using Gafchromic films exposed in interlaced geometries with their steep profiles highlight the potential to deposit radiotoxic doses in the vicinity of radiosensitive tissues.

  14. Novel DDR Processing of Corn Stover Achieves High Monomeric Sugar Concentrations from Enzymatic Hydrolysis (230 g/L) and High Ethanol Concentration (10% v/v) During Fermentation

    Chen, Xiaowen; Jennings, Ed; Shekiro, Joe; Kuhn, Erik M.; O' Brien, Marykate; Wang, Wei; Schell, Daniel J.; Himmel, Mike; Elander, Richard T.; Tucker, Melvin P.

    2015-04-03

    Distilling and purifying ethanol, butanol, and other products from second and later generation lignocellulosic biorefineries adds significant capital and operating cost for biofuels production. The energy costs associated with distillation affects plant gate and life cycle analysis costs. Lower titers in fermentation due to lower sugar concentrations from pretreatment increase both energy and production costs. In addition, higher titers decrease the volumes required for enzymatic hydrolysis and fermentation vessels. Therefore, increasing biofuels titers has been a research focus in renewable biofuels production for several decades. In this work, we achieved over 200 g/L of monomeric sugars after high solids enzymatic hydrolysis using the novel deacetylation and disc refining (DDR) process on corn stover. The high sugar concentrations and low chemical inhibitor concentrations from the DDR process allowed ethanol titers as high as 82 g/L in 22 hours, which translates into approximately 10 vol% ethanol. To our knowledge, this is the first time that 10 vol% ethanol in fermentation derived from corn stover without any sugar concentration or purification steps has been reported. Techno-economic analysis shows the higher titer ethanol achieved from the DDR process could significantly reduce the minimum ethanol selling price from cellulosic biomass.

  15. Sex-specific foraging behavior in response to fishing activities in a threatened seabird.

    García-Tarrasón, Manuel; Bécares, Juan; Bateman, Santiago; Arcos, José Manuel; Jover, Lluís; Sanpera, Carolina

    2015-06-01

    Some seabird species have learnt to efficiently exploit fishing discards from trawling activities. However, a discard ban has been proposed as necessary in Europe to ensure the sustainability of the seas. It is of crucial importance for the management and conservation purposes to study the potential consequences of a discard ban on the foraging ecology of threatened seabirds. We assessed the influence of fishing activities on the feeding habits of 22 male and 15 female Audouin's gulls (Larus audouinii) from the Ebro Delta (Mediterranean Sea) during the breeding period using GPS loggers together with Stable Isotope Analysis (SIA), which provided new insights into their foraging behavior and trophic ecology, respectively. GPS data revealed different sex-specific foraging patterns between workdays and weekends. Females were highly consistent in that they foraged at sea throughout the week even though discarding stops at weekends. In contrast, males switched from foraging at sea during the week (when discards are produced) to an increased use of rice field habitats at weekends (when fishermen do not work). This sex-specific foraging behavior could be related to specific nutritional requirements associated with previous egg production, an energetically demanding period for females. However, on a broader time scale integrated by the SIA, both sexes showed a high degree of individual specialization in their trophic ecology. The need to obtain detailed information on the dependence and response of seabirds to fishing activities is crucial in conservation sciences. In this regard, sex-specific foraging behavior in relation to fisheries has been overlooked, despite the ecological and conservation implications. For instance, this situation may lead to sex differentiation in bycatch mortality in longlines when trawlers do not operate. Moreover, any new fisheries policy will need to be implemented gradually to facilitate the adaptation of a specialized species to a discard ban

  16. Forage: A sensitive indicator for airborne radioactivity

    As a part of the radiological environmental monitoring program at the Joseph M. Parley Nuclear Plant to meet the requirements of NRC Regulations 10 CRF 50, Appendix I, routine sampling of forage was implemented. Indicator plots of forage (grass) were established at the plant site boundary in the two Meteorological sectors having the highest X/Q values for ground-level dispersion of airborne radioactivity. Likewise, a control plot was established in a sector having a significantly lower X/Q value at a distance of 18 miles. Procedures for maintenance of the grass plots, sampling of forage, and sample preparation for measurement of gamma radioactivity with a Ge (Li) detector were developed during the reported three year measurement period. Three atmospheric nuclear tests by the Peoples Republic of China in 1976 and 1977 has proven forage sampling to be convenient, sensitive, and in the judgement of the authors gives results which are superior to most other media sampled for airborne radioactivity. Typical measured levels of radioactivity from 150 to greater than 10,000 pCi/kg (dry weight) were obtained for the principal fission products in the Chinese bomb fallout, which included 95Zr-95Nb, 103Ru, 131I, 140Ba-140La, 141Ce, and 144Ce. On a unit weight basis the level of radioactivity measured was consistently higher for forage than for green leafy vegetables. This was attributed to the higher surface area for the forage. For comparison, plots of airborne concentrations for gross beta and particulate gamma emitters are shown during the time periods that include the Chinese nuclear tests. (author)

  17. Highlights on R and D work related to the achievement of high burnup with MOX fuel in commercial reactors

    Part of the R and D work made at BELGONUCLEAIRE in the field of high burnup achievement with MOX fuel in commercial LWRs is made through lnternational Programmes. Special attention is given to the evolution with burnup of fuel neutronic characteristics and of in-reactor rod thermal-mechanical behaviour. Pu burning in MOX is characterized essentially by a drop of Pu239 content. The other Pu isotopes have an almost unchanged concentration, due to internal breeding. The reactivity drop of MOX versus burnup is consequently much less pronounced than in UO2 fuel. Concentration of minor actinides Am and Cm becomes significant with burnup increase. These nuclides start to play a role on total reactivity and in the helium production. The thermal-mechanical behaviour of MOX fuel rod is very similar to that of UO2. Some specificities are noticed. The better PCI resistance recognized to MOX fuel has recently been confirmed. Three PWR MOX segments pm-irradiated up to 58 GWd/tM were ramped at 100 W/cm.min respectively to 430-450-500 W/cm followed by a hold time of 24 hours. No segment failed. MOX and UO2 fuels have different reactivities and operate thus at different powers. Moreover, radial distribution of power in MOX pellet is less depressed at high burnup than in UO2, leading to higher fuel central temperature for a same rating. The thermal conductivity of MOX fuel decreases with Pu content, typically 4% for 10% Pu. The combination of these three elements (power level, power profile, and conductivity) lead to larger FGR at high burnup compared to UO2. Helium production remains low compared to fission gas production (ratio < 0.2). As faster diffusing element, the helium fractional release is much higher than that of fission gas, leading to rod pressure increase comparable to the one resulting from fission gas. (author)

  18. Achievement of very low jitter extraction of high power proton beams in the J-PARC RCS

    The 3 GeV rapid cycling synchrotron (RCS) of the Japan Proton Accelerator Research Complex (J-PARC) delivers high intensity proton beams to the Materials and Life Science Facility (MLF) and the main ring (MR). The repetition rate of the RCS is 25 Hz. The typical operation period of the J-PARC is 3.2 s, which consists of 80 RCS cycles. Four beam pulses are for the MR and the other pulses are led into the MLF. Since a bucket-to-bucket injection scheme is used for the MR, the beam from the RCS must be injected with a precise phase to the proper rf bucket of the MR. In case of the MLF, the beam has to be synchronized to the Fermi chopper, which has a tolerance of only a few 100 ns. Thus, stable beam timings with a very low jitter are required for both destinations. To realize the stable beam timing, we employ the timing system, which is not synchronized to the AC power line. Also the magnetic-alloy accelerating cavities and the full digital low-level RF control system are the keys for the precise beam phase control. For acceleration of a high power beam, the phase feedback loop, which damps the longitudinal dipole oscillation, is necessary. The phase loop is a cause of the jitter of the beam extraction timing. We apply a gain pattern of the phase loop to avoid the influence on the beam phase at the extraction. We have achieved a very low jitter extraction of a high power beam within 1.7 ns, which corresponds to 1 degree of the rf frequency at the extraction.

  19. Achievement of very low jitter extraction of high power proton beams in the J-PARC RCS

    Tamura, Fumihiko; Yoshii, Masahito; Schnase, Alexander; Ohmori, Chihiro; Yamamoto, Masanobu; Nomura, Masahiro; Toda, Makoto; Shimada, Taihei; Hara, Keigo; Hasegawa, Katsushi

    2011-08-01

    The 3 GeV rapid cycling synchrotron (RCS) of the Japan Proton Accelerator Research Complex (J-PARC) delivers high intensity proton beams to the Materials and Life Science Facility (MLF) and the main ring (MR). The repetition rate of the RCS is 25 Hz. The typical operation period of the J-PARC is 3.2 s, which consists of 80 RCS cycles. Four beam pulses are for the MR and the other pulses are led into the MLF. Since a bucket-to-bucket injection scheme is used for the MR, the beam from the RCS must be injected with a precise phase to the proper rf bucket of the MR. In case of the MLF, the beam has to be synchronized to the Fermi chopper, which has a tolerance of only a few 100 ns. Thus, stable beam timings with a very low jitter are required for both destinations. To realize the stable beam timing, we employ the timing system, which is not synchronized to the AC power line. Also the magnetic-alloy accelerating cavities and the full digital low-level RF control system are the keys for the precise beam phase control. For acceleration of a high power beam, the phase feedback loop, which damps the longitudinal dipole oscillation, is necessary. The phase loop is a cause of the jitter of the beam extraction timing. We apply a gain pattern of the phase loop to avoid the influence on the beam phase at the extraction. We have achieved a very low jitter extraction of a high power beam within 1.7 ns, which corresponds to 1 degree of the rf frequency at the extraction.

  20. Optimal foraging predicts the ecology but not the evolution of host specialization in bacteriophages.

    Sébastien Guyader

    Full Text Available We explore the ability of optimal foraging theory to explain the observation among marine bacteriophages that host range appears to be negatively correlated with host abundance in the local marine environment. We modified Charnov's classic diet composition model to describe the ecological dynamics of the related generalist and specialist bacteriophages phiX174 and G4, and confirmed that specialist phages are ecologically favored only at high host densities. Our modified model accurately predicted the ecological dynamics of phage populations in laboratory microcosms, but had only limited success predicting evolutionary dynamics. We monitored evolution of attachment rate, the phenotype that governs diet breadth, in phage populations adapting to both low and high host density microcosms. Although generalist phiX174 populations evolved even broader diets at low host density, they did not show a tendency to evolve the predicted specialist foraging strategy at high host density. Similarly, specialist G4 populations were unable to evolve the predicted generalist foraging strategy at low host density. These results demonstrate that optimal foraging models developed to explain the behaviorally determined diets of predators may have only limited success predicting the genetically determined diets of bacteriophage, and that optimal foraging probably plays a smaller role than genetic constraints in the evolution of host specialization in bacteriophages.