Experiential Learning of Electronics Subject Matter in Middle School Robotics Courses

Science.gov (United States)

Rihtaršic, David; Avsec, Stanislav; Kocijancic, Slavko

2016-01-01

The purpose of this paper is to investigate whether the experiential learning of electronics subject matter is effective in the middle school open learning of robotics. Electronics is often ignored in robotics courses. Since robotics courses are typically comprised of computer-related subjects, and mechanical and electrical engineering, these…

Does tutor subject-matter expertise influence student achievement in ...

African Journals Online (AJOL)

Objective. To establish whether or not tutor subject-matter expertise influences student achievement in content-based examinations in the problem-based learning (PBL) curriculum at the University of Transkei (UNITRA) Medical School. Design. A retrospective study of MB ChB III student achievement in end-of-block ...

Prospective Science Teachers' Subject-Matter Knowledge about Overflow Container

Science.gov (United States)

Ültay, Eser

2016-01-01

The purpose of this study was to determine prospective science teachers' subject-matter knowledge (SMK) about overflow container. This study was carried out in the form of a case study in spring term of the academic year of 2013-2014 with seven sophomore prospective science teachers who were studying at Elementary Science Teaching Department in…

One Health in food safety and security education: Subject matter outline for a curricular framework.

Science.gov (United States)

Angelos, John A; Arens, Amanda L; Johnson, Heather A; Cadriel, Jessica L; Osburn, Bennie I

2017-06-01

Educating students in the range of subjects encompassing food safety and security as approached from a One Health perspective requires consideration of a variety of different disciplines and the interrelationships among disciplines. The Western Institute for Food Safety and Security developed a subject matter outline to accompany a previously published One Health in food safety and security curricular framework. The subject matter covered in this outline encompasses a variety of topics and disciplines related to food safety and security including effects of food production on the environment. This subject matter outline should help guide curriculum development and education in One Health in food safety and security and provides useful information for educators, researchers, students, and public policy-makers facing the inherent challenges of maintaining and/or developing safe and secure food supplies without destroying Earth's natural resources.

One Health in food safety and security education: Subject matter outline for a curricular framework

Directory of Open Access Journals (Sweden)

John A. Angelos

2017-06-01

Full Text Available Educating students in the range of subjects encompassing food safety and security as approached from a One Health perspective requires consideration of a variety of different disciplines and the interrelationships among disciplines. The Western Institute for Food Safety and Security developed a subject matter outline to accompany a previously published One Health in food safety and security curricular framework. The subject matter covered in this outline encompasses a variety of topics and disciplines related to food safety and security including effects of food production on the environment. This subject matter outline should help guide curriculum development and education in One Health in food safety and security and provides useful information for educators, researchers, students, and public policy-makers facing the inherent challenges of maintaining and/or developing safe and secure food supplies without destroying Earth's natural resources.

Problems Faced By Elementary School Second Grade English Subject Matter Teachers

Directory of Open Access Journals (Sweden)

Belgin Bal Incebacak

2017-11-01

Full Text Available The objective of thisstudy isto determine the problems experienced by subject matter teachers while instructing English lessons in the second grade of elementary school. What are the problemsfaced by English subject matter teachers when they instruct in 2nd grade lessons? In this research the descriptive modeling, which is one of the qualitative research methods, was employed. In accordance with this objective, we worked with 8 subject matter teachers from 5 different schoolsinAtakum and Ilkadim districtslocated in downtown Samsun, through easily accessible case sampling. The semi-structured “English Course Interview Form’’was applied to the teachers. In the study, descriptive survey model was employed, since it was aimed to reveal the current status of qualitative research methods.According to the results obtained from the research, the content was configured and presented under 5 themes. They were categorized as: 1. the problems experienced in classroom management, 2. the problems in physical and cognitive readiness, 3. the problems experienced in the learning and teacher process, 4. the problems seen in counseling, 5. the problems experienced in assessment and evaluation. In conclusion, the teachers stated that they had problems with managing the classroom, especially with the second grade students, whom are younger than others. It is observed that the change for teaching English at a younger age has been appropriate. Our teachersstated that they required in-service training so as to adapt to this aforementioned change.

[Study on retention and stability of linear occlusal complete dentures].

Science.gov (United States)

Zhang, Ping; Xu, Jun

2003-01-01

To learn retention and stability of linear occlusal complete dentures by investigating the subjective feelings of patient and the value of retention force. Static retention forces of maxillary and mandibular dentures were measured for 25 patients wearing linear occlusal dentures by using Hz-1 retention dynamometer. The subjective feelings of patients in functional state were gained simultaneously through questionnaire. Linear occlusal dentures demonstrate good retention in static and dynamic state. Among patients with severe resorption of residual ridge (RRR), mandibular linear occlusal dentures (shown good retentive subjective feelings) demonstrate significantly smaller retention force than those with slight or medium degree of RRR. There is no correlation between the subjective feelings and the values of retention forces of mandibular dentures. The subjective feelings of patients wearing new linear occlusal dentures are much better than that of old anatomic occlusal dentures. Linear occlusal dentures improve the performances of dentures by enhancing their stability during mastication movement.

What Do Subject Matter Experts Have to Say about Participating in Education and Outreach?

Science.gov (United States)

Manning, Colleen; NASA's Universe of Learning Team

2018-01-01

NASA’s Universe of Learning partners wish to actively engage with Subject Matter Experts (scientists and engineers) throughout the design, development, and delivery of products, programs, and professional development. In order to ensure these engagement efforts aligned with the needs of Subject Matter Experts, the external evaluators conducted an online survey. The subject pool included the scientists and engineers employed at the partner organizations as well as other scientists and engineers affiliated with NASA’s Astrophysics missions and research programs. This presentation will describe scientists’/engineers’ interest in various types of education/outreach, their availability to participate in education/outreach, factors that would encourage their participation in education/outreach, and the preparation and support they have for participation in education/outreach.

Research on U.S. Military Women: Recruitment and Retention Challenges and Strategies.

Science.gov (United States)

Braun, Lisa A; Kennedy, Holly P; Sadler, Lois S; Dixon, Jane

2015-12-01

To examine literature on recruitment and retention of military women in research studies as an underrepresented, and potentially marginalized, population. A literature search was conducted to examine challenges, identify potential barriers and facilitators, and to inform strategies for recruitment and retention of military women in research studies. This search was supplemented by findings in military-specific databases and discussions with Military Women's Health Research Interest Group subject matter experts. Ten articles addressed research recruitment and retention challenges and strategies in marginalized/underrepresented populations, providing an effective context to inform research recruitment and retention in military settings. Research with military women is often challenged by logistical, cultural, social, ethical, and methodological issues, which may hinder exploration of potentially sensitive issues. Researchers must consider military-specific challenges to conducting research that include lengthy deployments, unpredictable military exercises, and foreign assignments, in accessing research participants. A case example shows strategies used in a military cervical cancer screening study. There are few published articles specific to research recruitment and retention in female military populations. Available resources broadly address recruitment challenges for Veterans, marginalized, hard-to-access, and transient research participants, which may provide guidance and strategies for success when applied to military populations. Reprint & Copyright © 2015 Association of Military Surgeons of the U.S.

Retention Matters: Academic Libraries Leading the Way

Science.gov (United States)

Oliveira, Silas M.

2018-01-01

Academic libraries have always strived to be purposively involved in the university's mission attainment efforts. Today, the increase of retention levels is paramount, and, in many cases, it is at the center of higher education institution's strategic plans. For Andrews University, for example, the goal is to reach 80% in the next five years. In…

Keeping students in by sending them out: Retention and service-learning

Directory of Open Access Journals (Sweden)

Iris Mae Yob

2014-06-01

Full Text Available This review of recent literature examines the research on the impact of service-learning on student retention.  The theoretical framework of the review draws on both Tinto’s model of student attrition and Knowles’s theory of adult learning, which together suggest that academic and social integration, active participation and engagement in learning, and application and relevancy of the subject-matter under study are key factors in student success. The role of these factors has been confirmed in a growing body of research around learning experiences in general and, as this review shows, particularly in service-learning experiences. Suggestions are made for how future research might expand and critically deepen this evidence and offers some implications for service-learning as a means of improving student retention. DOI: 10.18870/hlrc.v4i2.177

Prospective outcome of the influence of complexation by natural organic matter on enhanced or retarded transport of radionuclides: case of humic substances retention

International Nuclear Information System (INIS)

Reiller, P.

2010-01-01

This document takes a prospective stock of the natural organic matter influence on the possible effects on radionuclide migration, as well as a brief critical analysis of the literature data. A comparison with the retention of the 'simple' organic complexing agents is done in order to fix the limit of the 'simplistic' analogies done in the literature very often. It appears that the magnitude of the effects is function of the residence time in the medium, and of the possibilities for the organic complexes to be retained on the mineral surfaces. The contact time between radionuclides and the natural organic matter is also an influent parameter, as it influences part of the reversibility of this interaction vis-a-vis surface retention. Modelling of the metal-organic-surface systems is only satisfying up to now when accounting fractions of organic matter that are less susceptible to form colloidal aggregates, i.e., fulvic acids. These non-aggregated fractions could be considered as simple ligands in a first approximation. Conversely, when it comes to aggregated colloids of organic origin, i.e., humic acids, modelling are limited by the lack of theoretical understanding of their structure and of their evolution in response to geochemical condition variations, as ionic strength (harsh meteoric events), acidity or water composition (non-saturated water table). (author)

Does skill retention benefit from retentivity and symbolic rehearsal? - two studies with a simulated process control task.

Science.gov (United States)

Kluge, Annette; Frank, Barbara; Maafi, Sanaz; Kuzmanovska, Aleksandra

2016-05-01

Two experiments were designed to compare two symbolic rehearsal refresher interventions (imaginary practice, a hidden introspective process) and investigate the role of retentivity in skill retention. Retentivity is investigated as the ability to memorise and reproduce information and associations that were learned a short time ago. Both experiments comprised initial training (week 1), a symbolic rehearsal for the experimental group (week 2) and a retention assessment (week 3). In the first study, the experimental group received a symbolic rehearsal, while the control group received no rehearsal. In the second study, the experimental group received the same symbolic rehearsal used in study 1, enhanced with rehearsal tasks addressing human-computer interaction. The results showed that both symbolic rehearsal interventions were equally likely to mitigate skill decay. The retentivity showed medium to high correlations with skill retention in both studies, and the results suggest that subjects high in retentivity benefit more from a symbolic rehearsal refresher intervention. Practitioner Summary: Skill decay becomes a problem in situations in which jobs require the correct mastery of non-routine situations. Two experimental studies with simulated process control tasks showed that symbolic rehearsal and retentivity can significantly mitigate skill decay and that subjects higher in retentivity benefit more from refresher interventions.

Diffusion tensor imaging identifies deficits in white matter microstructure in subjects with type 1 diabetes that correlate with reduced neurocognitive function.

Science.gov (United States)

Kodl, Christopher T; Franc, Daniel T; Rao, Jyothi P; Anderson, Fiona S; Thomas, William; Mueller, Bryon A; Lim, Kelvin O; Seaquist, Elizabeth R

2008-11-01

Long-standing type 1 diabetes is associated with deficits on neurocognitive testing that suggest central white matter dysfunction. This study investigated whether diffusion tensor imaging (DTI), a type of magnetic resonance imaging that measures white matter integrity quantitatively, could identify white matter microstructural deficits in patients with long-standing type 1 diabetes and whether these differences would be associated with deficits found by neurocognitive tests. Twenty-five subjects with type 1 diabetes for at least 15 years and 25 age- and sex-matched control subjects completed DTI on a 3.0 Tesla scanner and a battery of neurocognitive tests. Fractional anisotropy was calculated for the major white matter tracts of the brain. Diabetic subjects had significantly lower mean fractional anisotropy than control subjects in the posterior corona radiata and the optic radiation (P < 0.002). In type 1 diabetic subjects, reduced fractional anisotropy correlated with poorer performance on the copy portion of the Rey-Osterreith Complex Figure Drawing Test and the Grooved Peg Board Test, both of which are believed to assess white matter function. Reduced fractional anisotropy also correlated with duration of diabetes and increased A1C. A history of severe hypoglycemia did not correlate with fractional anisotropy. DTI can detect white matter microstructural deficits in subjects with long-standing type 1 diabetes. These deficits correlate with poorer performance on selected neurocognitive tests of white matter function.

Comparison of qualitative and quantitative imaging characteristics of [11C]PiB and [18F]flutemetamol in normal control and Alzheimer's subjects

Directory of Open Access Journals (Sweden)

James M. Mountz

2015-01-01

Conclusions: [11C]PiB and [18F]flutemetamol have similar retention characteristics across a range of amyloid negative to positive subjects. Both tracers performed similarly when a standardized visual read technique was used to classify scans as amyloid-positive or amyloid-negative and correlated well with SUVR classifications. However, care in visual interpretation of amyloid positive versus amyloid negative regions should be taken, particularly in the case of [18F]flutemetamol when considering cortical vs. white-matter retention.

Primary teachers' subject matter knowledge: decimals

Science.gov (United States)

Ubuz, Behiye; Yayan, Betül

2010-09-01

The main objective of this study was to investigate primary teachers' subject matter knowledge in the domain of decimals and more elaborately to investigate their performance and difficulties in reading scale, ordering numbers, finding the nearest decimal and doing operations, such as addition and subtraction. The difficulties in these particular areas are analysed and suggestions are made regarding their causes. Further, factors that influence this knowledge were explored. The sample of the study was 63 primary teachers. A decimal concepts test including 18 tasks was administered and the total scores for the 63 primary teachers ranged from 3 to 18 with a mean and median of 12. Fifty per cent of the teachers were above the mean score. The detailed investigation of the responses revealed that the primary teachers faced similar difficulties that students and pre-service teachers faced. Discrepancy on teachers' knowledge revealed important differences based on educational level attained, but not the number of years of teaching experience and experience in teaching decimals. Some suggestions have been made regarding the implications for pre- and in-service teacher training.

Urban Extension: Aligning with the Needs of Urban Audiences Through Subject-Matter Centers

Directory of Open Access Journals (Sweden)

Brad Gaolach

2017-06-01

Full Text Available The educational program model is the principle approach Extension uses to deliver on its mission of “taking knowledge to the people.” However, with county-based faculty fully engaged in long-term program delivery, they may have little or no capacity to address emerging issues faced by urban communities. Urban governments often seek the research capacity of a university in addition to, or instead of, the traditional Extension programming model but sometimes turn first to other urban-serving universities. Washington State University Extension has addressed these challenges by establishing subject-matter centers. This article examines how subject-matter centers can add capacity to traditional Extension offices in order to be responsive to emerging local needs, suggesting models that other university Extension programs may use or adapt to their local communities. These models also foster more community engagement and articulate greater public value for the institution as a whole.

Developing a Democratic View of Academic Subject Matters: John Dewey, William Chandler Bagley, and Boyd Henry Bode

Science.gov (United States)

Watras, Joseph

2012-01-01

In the first half of the twentieth century, the ideal of democracy influenced the conceptions people had of the academic subject matters. A common criticism was that abstract academic subjects served aristocratic societies. Although most theorists considered the academic subjects to be important, they had differing views on the conception of…

Being in a romantic relationship is associated with reduced gray matter density in striatum and increased subjective happiness

Directory of Open Access Journals (Sweden)

Hiroaki Kawamichi

2016-11-01

Full Text Available Romantic relationship, a widespread feature of human society, is one of the most influential factors in daily life. Although stimuli related to romantic love or being in a romantic relationship commonly result in enhancement of activation or functional connectivity of the reward system, including the striatum, the structure underlying romantic relationship-related regions remain unclear. Because individual experiences can alter gray matter within the adult human brain, we hypothesized that romantic relationship is associated with structural differences in the striatum related to the positive subjective experience of being in a romantic relationship. Because intimate romantic relationships contribute to perceived subjective happiness, this subjective enhancement of happiness might be accompanied by the experience of positive events related to being in a romantic relationship. To test this hypothesis and elucidate the structure involved, we compared subjective happiness, an indirect measure of the existence of positive experiences caused by being in a romantic relationship, of participants with or without romantic partners (N = 68. Furthermore, we also conducted a voxel-based morphometry (VBM study of the effects of being in a romantic relationship (N = 113. Being in a romantic relationship was associated with greater subjective happiness and reduced gray matter density within the right dorsal striatum. These results suggest that being in a romantic relationship enhances perceived subjective happiness via positive experiences. Furthermore, the observed reduction in gray matter density in the right dorsal striatum may reflect an increase in saliency of social reward within a romantic relationship. Thus, being in a romantic relationship is associated with positive experiences and a reduction of gray matter density in the right dorsal striatum, representing a modulation of social reward.

48 CFR 970.0407 - Contractor records retention.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Contractor records retention. 970.0407 Section 970.0407 Federal Acquisition Regulations System DEPARTMENT OF ENERGY AGENCY SUPPLEMENTARY REGULATIONS DOE MANAGEMENT AND OPERATING CONTRACTS Administrative Matters 970.0407 Contractor...

Hot-electron surface retention in intense short-pulse laser-matter interactions.

Science.gov (United States)

Mason, R J; Dodd, E S; Albright, B J

2005-07-01

Implicit hybrid plasma simulations predict that a significant fraction of the energy deposited into hot electrons can be retained near the surface of targets with steep density gradients illuminated by intense short-pulse lasers. This retention derives from the lateral transport of heated electrons randomly emitted in the presence of spontaneous magnetic fields arising near the laser spot, from geometric effects associated with a small hot-electron source, and from E fields arising in reaction to the ponderomotive force. Below the laser spot hot electrons are axially focused into a target by the B fields, and can filament in moderate Z targets by resistive Weibel-like instability, if the effective background electron temperature remains sufficiently low. Carefully engineered use of such retention in conjunction with ponderomotive density profile steepening could result in a reduced hot-electron range that aids fast ignition. Alternatively, such retention may disturb a deeper deposition needed for efficient radiography and backside fast ion generation.

DIAFILTRATION OF ULTRAFILTRATION RETENTATE OF WHEY FROM WHITE BRINED CHEESE

Directory of Open Access Journals (Sweden)

Maria DUSHKOVA

2012-03-01

Full Text Available Whey diafiltration was carried out with a UF25-PAN polyacrylnitrilic membrane with 25 kDa molecular weight cut-off at volume reduction factors (VRF VRF=2, VRF=4, VRF=6, VRF=8, VRF=10. The values of the principal components dry matter, protein, lactose and mineral substances in the retentates and permeate obtained were established. The relative shares of protein, lactose and mineral substances in the dry matter, the concentration factor (CF values for dry matter, protein, lactose and mineral substances, and the protein retention factor (RF were determined. Linear models were created for the CF of each investigated component according to the VRF, and a logarithmic model was developed for the protein RF according to the VRF. The results obtained demonstrated the efficiency of diafiltration for deep treatment aimed at a further elimination of lactose and mineral substances and subsequent utilization of the diafiltration concentrates low in lactose and mineral substances as a liquid supplement in the manufacture of extruded cereal products.

In-vivo tissue uptake and retention of Sn-117m(4+)DTPA in a human subject with metastatic bone pain and in normal mice

International Nuclear Information System (INIS)

Swailem, Fayez M.; Krishnamurthy, Gerbail T.; Srivastava, Suresh C.; Aguirre, Maria L.; Ellerson, Dawn L.; Walsh, T. Kent; Simpson, Laura

1998-01-01

Organ and tissue uptake and retention of Sn-117m(4+)DTPA were studied in a human subject treated for metastatic bone pain, and the results were compared with the biodistribution studies in five normal mice. The explanted organs from a patient who received a therapy dose of 18.6 mCi (688.2 MBq) Sn-117m(4+)DTPA and who died 47 days later were imaged with a γ-camera, and tissue samples were counted and also autoradiographed. Bone, muscle, liver, fat, lungs, kidneys, spleen, heart and pancreas tissue samples were assayed in a well counter for radioactivity. Regions of interest were drawn over bone and major organs to calculate and quantify clearance times using three in vivo Sn-117m(4+)DTPA whole-body scintigrams acquired at 1, 24 and 168 h after injection. Five normal mice injected with the same batch of Sn-117m(4+)DTPA as used for the human subject were sacrificed at 24 h, and tissue samples were collected and assayed for radioactivity for comparison with the human data. For the human subject, whole-body retention at 47 days postinjection was 81% of the injected dose, and the rest (19%) was excreted in urine. Of the whole-body retained activity at 47 days, 82.4% was in bone, 7.8% in the muscle and 1.5% in the liver, and the rest was distributed among other tissues. γ-Ray scintigrams and electron autoradiographs of coronal slices of the thoracolumbar vertebral body showed heterogenous metastatic involvement with normal bone between metastatic lesions. There was nonuniform distribution of radioactivity even within a single vertebral body, indicating normal bone between metastatic lesions. Lesion-to-nonlesion ratios ranged from 3 to 5. However, the osteoid-to-marrow cavity deposition ratio, from the microautoradiographs, was 11:1. The peak uptake in the human bone was seen at 137 h with no biological clearance. Soft tissues showed peak uptake at 1 h and exhibited three compartmental clearance components. Whole-body retention in normal mice was 38.7% of the injected

Influence of tutors' subject-matter expertise on student effort and achievement in problem-based learning

NARCIS (Netherlands)

H.G. Schmidt (Henk); A. van der Arend (Arie); J.H.C. Moust (Jos); I. Kokx (Irma); L. Boon (Louis)

1993-01-01

textabstractPurpose. To investigate the effects of tutors' subject-matter expertise on students' levels of academic achievement and study effort in a problem-based health sciences curriculum. Also, to study differences in turors' behaviors and the influences of these differences on students'

{sup 1}H and {sup 31}P magnetic resonance spectroscopic imaging of white matter signal hyperintensity areas in elderly subjects

Energy Technology Data Exchange (ETDEWEB)

Constans, J M [Department of Veterans Affairs Medical Center and University of California Magnetic Resonance Unit, San Francisco, CA (United States); [California Univ., San Francisco, CA (United States). Dept. of Radiology; Meyerhoff, D J [Department of Veterans Affairs Medical Center and University of California Magnetic Resonance Unit, San Francisco, CA (United States); [California Univ., San Francisco, CA (United States). Dept. of Radiology; Norman, D [California Univ., San Francisco, CA (United States). Dept. of Radiology; Fein, G [Department of Veterans Affairs Psychiatry Service, University of California, San Francisco, California (United States); [University of California, San Francisco, CA (United States). Dept. of Psychiatry; Weiner, M W [Department of Veterans Affairs Medical Center and University of California Magnetic Resonance Unit, San Francisco, CA (United States); [California Univ., San Francisco, CA (United States). Dept. of Radiology; [California Univ., San Francisco, CA (United States). Dept. of Medicine; [DVA Medical Center, Magnetic Resonance Spectroscopy Unit, San Francisco, CA (United States)

1995-11-01

White matter signal hyperintensities (WMSH) are commonly seen on MRI of elderly subjects. The purpose of this study was to characterize metabolic changes in the white matter of elderly subjects with extensive WMSH. We used water-suppressed proton ({sup 1}H) magnetic resonance spectroscopic imaging (MRSI) to compare six subjects with extensive WMSH with eight age-matched elderly subjects with minimal or absent WMSH, and phosphorus ({sup 31}P) MRSI to compare nine subjects with extensive WMSH and seven age-matched elderly subjects without extensive WMSH. Relative to region-matched tissue in elderly controls, extensive WMSH were associated with increased signal from choline-containing metabolites, no significant change of signal from N-acetylaspartate, and a trend to a decreased phosphomonoester (PME) resonance. These findings suggest that WMSH may be associated with an alteration of brain myelin phospholipids in the absence of axonal damage. There were no differences in energy phosphates, consistent with lack of ongoing brain ischemia. Within the group with extensive WMSH, PME resonance measures were significantly lower in WMSH than in contralateral normal-appearing white matter. These results provide information on pathophysiology of WMSH and a basis for comparison with WMSH in Alzheimer`s disease, vascular dementia, multiple sclerosis, and other diseases. (orig.). With 4 figs., 4 tabs.

Evaluation of Removal Mechanisms in a Graphene Oxide-Coated Ceramic Ultrafiltration Membrane for Retention of Natural Organic Matter, Pharmaceuticals, and Inorganic Salts.

Science.gov (United States)

Chu, Kyoung Hoon; Fathizadeh, Mahdi; Yu, Miao; Flora, Joseph R V; Jang, Am; Jang, Min; Park, Chang Min; Yoo, Sung Soo; Her, Namguk; Yoon, Yeomin

2017-11-22

Functionalized graphene oxide (GO), derived from pure graphite via the modified Hummer method, was used to modify commercially available ceramic ultrafiltration membranes using the vacuum method. The modified ceramic membrane functionalized with GO (ceramic GO ) was characterized using a variety of analysis techniques and exhibited higher hydrophilicity and increased negative charge compared with the pristine ceramic membrane. Although the pure water permeability of the ceramic GO membrane (14.4-58.6 L/m 2 h/bar) was slightly lower than that of the pristine membrane (25.1-62.7 L/m 2 h/bar), the removal efficiencies associated with hydrophobic attraction and charge effects were improved significantly after GO coating. Additionally, solute transport in the GO nanosheets of the ceramic GO membrane played a vital role in the retention of target compounds: natural organic matter (NOM; humic acid and tannic acid), pharmaceuticals (ibuprofen and sulfamethoxazole), and inorganic salts (NaCl, Na 2 SO 4 , CaCl 2 , and CaSO 4 ). While the retention efficiencies of NOM, pharmaceuticals, and inorganic salts in the pristine membrane were 74.6%, 15.3%, and 2.9%, respectively, these increased to 93.5%, 51.0%, and 31.4% for the ceramic GO membrane. Consequently, the improved removal mechanisms of the membrane modified with functionalized GO nanosheets can provide efficient retention for water treatment under suboptimal environmental conditions of pH and ionic strength.

Development Of Phisyics Learning Documents Based Student's Learning Style In The Matter Of Temperature And Heat Subjects Of Class X High School

OpenAIRE

Resty Noriwita, Indah Resty Noriwita Indah; Nasir, Muhammad Nasir Muhammad; Ma’aruf, Zuhdi Ma’aruf Zuhdi

2015-01-01

This study aims to produce a learning documents physicsbased learning styles of students in the matter of temperature and heat of class subjectS X SMA valid. The subjects were learning documents that consists of a lesson plan (RPP), worksheets (LKS), medium of learning and achievement test of cognitive, affective, process, and psychomotor. Data collection instrument in this study is an instrument validity device physics-based learning students' learning styles in the matter of temperature and...

Do Subject Matter Knowledge, and Pedagogical Content Knowledge Constitute the Ideal Gas Law of Science Teaching?

Science.gov (United States)

Lederman, Norman G.; Gess-Newsome, Julie

1992-01-01

Describes Pedagogical Content Knowledge and focuses on the empirical research directly concerned with the relationship between science teachers' subject matter knowledge or structures and actual classroom practice. Concludes there is little evidence that a relationship exists. (PR)

Incidental white-matter foci on MRI in ''healthy'' subjects: evidence of subtle cognitive dysfunction

International Nuclear Information System (INIS)

Baum, K.A.; Schulte, C.; Girke, W.; Reischies, F.M.; Felix, R.

1996-01-01

The clinical significance of incidental white-matter foci seen on MRI is controversial. Mainly using a computer-assisted neuropsychological test battery, we tested the hypothesis that there is a clinical correlate of these foci. We studied 41 individuals aged 45-65 years with no history of neurological or psychiatric disorder, in whom no indication of central nervous system abnormalities was found on standardised neurological examination. A computer-assisted neuropsychological test battery, with the advantage of precise measuring of both time and deviation (e. g. in position memory tests), and rating scales for emotional dysfunction were administered; selected soft neurological signs were assessed. In 16 subjects (39 %) MRI showed high-signal foci in the white matter on spin-echo sequences. White-matter foci not adjacent to the lateral ventricles were found to be related to performance on immediate visual memory/visuoperceptual skills, visuomotor tracking/psychomotor speed and, to a lesser degree, learning capacity and abstract and conceptual reasoning skills. Subtle cognitive dysfunction would appear to be a clinical correlate of punctate white-matter foci on MRI of otherwise ''healty'' individuals. (orig.). With 1 fig., 2 tabs

Water retention and availability in soils of the State of Santa Catarina-Brazil: effect of textural classes, soil classes and lithology

Directory of Open Access Journals (Sweden)

André da Costa

2013-12-01

Full Text Available The retention and availability of water in the soil vary according to the soil characteristics and determine plant growth. Thus, the aim of this study was to evaluate water retention and availability in the soils of the State of Santa Catarina, Brazil, according to the textural class, soil class and lithology. The surface and subsurface horizons of 44 profiles were sampled in different regions of the State and different cover crops to determine field capacity, permanent wilting point, available water content, particle size, and organic matter content. Water retention and availability between the horizons were compared in a mixed model, considering the textural classes, the soil classes and lithology as fixed factors and profiles as random factors. It may be concluded that water retention is greater in silty or clayey soils and that the organic matter content is higher, especially in Humic Cambisols, Nitisols and Ferralsol developed from igneous or sedimentary rocks. Water availability is greater in loam-textured soils, with high organic matter content, especially in soils of humic character. It is lower in the sandy texture class, especially in Arenosols formed from recent alluvial deposits or in gravelly soils derived from granite. The greater water availability in the surface horizons, with more organic matter than in the subsurface layers, illustrates the importance of organic matter for water retention and availability.

Total body retention of orally administered 47Ca in primary hyperparathyroidism

International Nuclear Information System (INIS)

Mallette, L.E.; Sode, J.E.; Marx, S.J.; Georges, L.P.; Aurbach, G.D.

1975-01-01

Using a whole-body radiation detector, the total-body retention of 47 Ca 7 days after oral administration of the isotope to patients with various disorders of calcium metabolism was measured. The percent retention of 47 Ca given with 90 mg of unlabeled (carrier) calcium varied with the calcium metabolic status as follows: normals (n = 14), 33--43 percent (mean 38); primary hyperparathyroidism (n = 28), 32--74 percent (mean 52); idiopathic hypercalciuria (n = 9), 34--49 percent (mean 42); and hypercalcemia of other etiology (n = 3), 23--26 percent (mean 25). Almost half (13/28) of those with hyperparathyroidism showed a retention above 55 percent, distinguishing them from subjects with idiopathic hypercalciuria. Retention of 47 Ca correlated poorly with clinical measures of severity of hyperparathyroidism. When isotope was diluted with a smaller amount of carrier calcium (20 mg), retention was increased in normals (n = 5) to 46--54 percent (mean 50) and in hyperparathyroidism (n = 5) to 64--87 percent (mean 73). After surgical cure of hyperparathyroidism retention of isotope returned toward normal in 5 of 7 subjects. Whole-body retention of orally administered 47 Ca may prove useful in detecting hyperparathyroidism in subjects with mild hypercalcemia or hypercalciuria. (U.S.)

Insight on AV-45 binding in white and grey matter from histogram analysis: a study on early Alzheimer's disease patients and healthy subjects

Science.gov (United States)

Nemmi, Federico; Saint-Aubert, Laure; Adel, Djilali; Salabert, Anne-Sophie; Pariente, Jérémie; Barbeau, Emmanuel; Payoux, Pierre; Péran, Patrice

2014-01-01

Purpose AV-45 amyloid biomarker is known to show uptake in white matter in patients with Alzheimer’s disease (AD) but also in healthy population. This binding; thought to be of a non-specific lipophilic nature has not yet been investigated. The aim of this study was to determine the differential pattern of AV-45 binding in healthy and pathological populations in white matter. Methods We recruited 24 patients presenting with AD at early stage and 17 matched, healthy subjects. We used an optimized PET-MRI registration method and an approach based on intensity histogram using several indexes. We compared the results of the intensity histogram analyses with a more canonical approach based on target-to-cerebellum Standard Uptake Value (SUVr) in white and grey matters using MANOVA and discriminant analyses. A cluster analysis on white and grey matter histograms was also performed. Results White matter histogram analysis revealed significant differences between AD and healthy subjects, which were not revealed by SUVr analysis. However, white matter histograms was not decisive to discriminate groups, and indexes based on grey matter only showed better discriminative power than SUVr. The cluster analysis divided our sample in two clusters, showing different uptakes in grey but also in white matter. Conclusion These results demonstrate that AV-45 binding in white matter conveys subtle information not detectable using SUVr approach. Although it is not better than standard SUVr to discriminate AD patients from healthy subjects, this information could reveal white matter modifications. PMID:24573658

Insight on AV-45 binding in white and grey matter from histogram analysis: a study on early Alzheimer's disease patients and healthy subjects

International Nuclear Information System (INIS)

Nemmi, Federico; Saint-Aubert, Laure; Peran, Patrice; Adel, Djilali; Salabert, Anne-Sophie; Payoux, Pierre; Pariente, Jeremie; Barbeau, Emmanuel J.

2014-01-01

AV-45 amyloid biomarker is known to show uptake in white matter in patients with Alzheimer's disease (AD), but also in the healthy population. This binding, thought to be of a non-specific lipophilic nature, has not yet been investigated. The aim of this study was to determine the differential pattern of AV-45 binding in white matter in healthy and pathological populations. We recruited 24 patients presenting with AD at an early stage and 17 matched, healthy subjects. We used an optimized positron emission tomography-magnetic resonance imaging (PET-MRI) registration method and an approach based on an intensity histogram using several indices. We compared the results of the intensity histogram analyses with a more canonical approach based on target-to-cerebellum Standard Uptake Value (SUVr) in white and grey matter using MANOVA and discriminant analyses. A cluster analysis on white and grey matter histograms was also performed. White matter histogram analysis revealed significant differences between AD and healthy subjects, which were not revealed by SUVr analysis. However, white matter histograms were not decisive to discriminate groups, and indices based on grey matter only showed better discriminative power than SUVr. The cluster analysis divided our sample into two clusters, showing different uptakes in grey, but also in white matter. These results demonstrate that AV-45 binding in white matter conveys subtle information not detectable using the SUVr approach. Although it is not more efficient than standard SUVr in discriminating AD patients from healthy subjects, this information could reveal white matter modifications. (orig.)

Indigenous Students' Voices: Monitoring Indigenous Student Satisfaction and Retention in a Large Australian University

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Shah, Mahsood; Widin, Jacquie

2010-01-01

Indigenous student satisfaction with the university learning and teaching experience matters. From a student perspective, retention matters as successful completion of tertiary education improves the life chances of students in relation to employment opportunities, being able to support themselves financially and contributing to the society in…

Glucose metabolism, gray matter structure, and memory decline in subjective memory impairment.

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Scheef, Lukas; Spottke, Annika; Daerr, Moritz; Joe, Alexius; Striepens, Nadine; Kölsch, Heike; Popp, Julius; Daamen, Marcel; Gorris, Dominik; Heneka, Michael T; Boecker, Henning; Biersack, Hans J; Maier, Wolfgang; Schild, Hans H; Wagner, Michael; Jessen, Frank

2012-09-25

To identify biological evidence for Alzheimer disease (AD) in individuals with subjective memory impairment (SMI) and unimpaired cognitive performance and to investigate the longitudinal cognitive course in these subjects. [¹⁸F]fluoro-2-deoxyglucose PET (FDG-PET) and structural MRI were acquired in 31 subjects with SMI and 56 controls. Cognitive follow-up testing was performed (average follow-up time: 35 months). Differences in baseline brain imaging data and in memory decline were assessed between both groups. Associations of memory decline with brain imaging data were tested. The SMI group showed hypometabolism in the right precuneus and hypermetabolism in the right medial temporal lobe. Gray matter volume was reduced in the right hippocampus in the SMI group. At follow-up, subjects with SMI showed a poorer performance than controls on measures of episodic memory. Longitudinal memory decline in the SMI group was associated with reduced glucose metabolism in the right precuneus at baseline. The cross-sectional difference in 2 independent neuroimaging modalities indicates early AD pathology in SMI. The poorer memory performance at follow-up and the association of reduced longitudinal memory performance with hypometabolism in the precuneus at baseline support the concept of SMI as the earliest manifestation of AD.

The Impact of Self-Perceived Subject Matter Knowledge on Pedagogical Decisions in EFL Grammar Teaching Practices

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Sanchez, Hugo Santiago

2014-01-01

Recent developments in language teacher cognition research highlight the need to explore subject matter knowledge in relation to classroom practice. This study examines the impact of two foreign language teachers' knowledge about grammar upon their pedagogical decisions. The primary database consisted of classroom observations and post-lesson…

Influence of humic fractions on retention of isoproturon residues in two Moroccan soils.

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Elkhattabi, Kaouakeb; Bouhaouss, Ahmed; Scrano, Laura; Lelario, Filomena; Bufo, Sabino A

2007-01-01

The influence of different fractions of soil organic matter on the retention of the herbicide isoproturon (IPU) has been evaluated. Water and methanol extractable residues of (14)C labeled isoproturon have been determined in two Moroccan soils by beta -counting-liquid chromatography. The quantification of bound residues in soil and in different fractions of soil humic substances has been performed using pyrolysis/scintillation-detected gas-chromatography. Microbial mineralization of the herbicide and soil organic matter has been also monitored. Retention of isoproturon residues after 30-days incubation ranged from 22% to 32% (non-extractable fraction). The radioactivity extracted in an aqueous environment was from 20% to 33% of the amount used for the treatment; meanwhile, methanol was able to extract another 48%. Both soils showed quantities of bound residues into the humin fraction higher than humic and fulvic acids. The total amount of residues retained into the organic matter of the soils was about 65 % of non-extractable fraction, and this percentage did not change with incubation time; on the contrary, the sorption rate of the retention reaction is mostly influenced by the clay fraction and organic content of the soil. Only a little part of the herbicide was mineralized during the experimental time.

Cross-sectional variations of white and grey matter in older hypertensive patients with subjective memory complaints

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Ahmed Chetouani

2018-01-01

Altogether, our findings show that cross-sectional variations in overall white brain matter are linked to the metabolism of Alzheimer-like cortical areas and to cognitive performance in older hypertensive patients with only subjective memory complaints. Additional relationships with central BP strengthen the hypothesis of a contributing pathogenic role of hypertension.

50 CFR 635.24 - Commercial retention limits for sharks and swordfish.

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2010-10-01

... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false Commercial retention limits for sharks and... Management Measures § 635.24 Commercial retention limits for sharks and swordfish. The retention limits in this section are subject to the quotas and closure provisions in §§ 635.27 and 635.28. (a) Sharks. (1...

Developing Pre-Service Teachers' Subject Matter Knowledge of Electromagnetism by Integrating Concept Maps and Collaborative Learning

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Govender, Nadaraj

2015-01-01

This case study explored the development of two pre-service teachers' subject matter knowledge (SMK) of electromagnetism while integrating the use of concept maps (CM) and collaborative learning (CL) strategies. The study aimed at capturing how these pre-service teachers' SMK in electromagnetism was enhanced after having been taught SMK in a…

Insight on AV-45 binding in white and grey matter from histogram analysis: a study on early Alzheimer's disease patients and healthy subjects

Energy Technology Data Exchange (ETDEWEB)

Nemmi, Federico; Saint-Aubert, Laure; Peran, Patrice [Inserm, Imagerie Cerebrale et Handicaps Neurologiques UMR 825, Centre Hospitalier Universitaire de Toulouse (France); Universite de Toulouse, UPS, Imagerie Cerebrale et Handicaps Neurologiques UMR 825, Centre Hospitalier Universitaire de Toulouse, Toulouse (France); Adel, Djilali; Salabert, Anne-Sophie; Payoux, Pierre [Inserm, Imagerie Cerebrale et Handicaps Neurologiques UMR 825, Centre Hospitalier Universitaire de Toulouse (France); Universite de Toulouse, UPS, Imagerie Cerebrale et Handicaps Neurologiques UMR 825, Centre Hospitalier Universitaire de Toulouse, Toulouse (France); Centre Hospitalier Universitaire de Toulouse, Service de Medecine Nucleaire, Pole Imagerie, Toulouse (France); Pariente, Jeremie [Inserm, Imagerie Cerebrale et Handicaps Neurologiques UMR 825, Centre Hospitalier Universitaire de Toulouse (France); Universite de Toulouse, UPS, Imagerie Cerebrale et Handicaps Neurologiques UMR 825, Centre Hospitalier Universitaire de Toulouse, Toulouse (France); Centre Hospitalier Universitaire de Toulouse, Service de Neurologie, Pole Neurosciences, Toulouse (France); Barbeau, Emmanuel J. [Centre Hospitalier Universitaire de Toulouse, Service de Neurologie, Pole Neurosciences, Toulouse (France); Universite de Toulouse, UPS, Centre de Recherche Cerveau et Cognition, CNRS, CerCo, Toulouse (France)

2014-07-15

AV-45 amyloid biomarker is known to show uptake in white matter in patients with Alzheimer's disease (AD), but also in the healthy population. This binding, thought to be of a non-specific lipophilic nature, has not yet been investigated. The aim of this study was to determine the differential pattern of AV-45 binding in white matter in healthy and pathological populations. We recruited 24 patients presenting with AD at an early stage and 17 matched, healthy subjects. We used an optimized positron emission tomography-magnetic resonance imaging (PET-MRI) registration method and an approach based on an intensity histogram using several indices. We compared the results of the intensity histogram analyses with a more canonical approach based on target-to-cerebellum Standard Uptake Value (SUVr) in white and grey matter using MANOVA and discriminant analyses. A cluster analysis on white and grey matter histograms was also performed. White matter histogram analysis revealed significant differences between AD and healthy subjects, which were not revealed by SUVr analysis. However, white matter histograms were not decisive to discriminate groups, and indices based on grey matter only showed better discriminative power than SUVr. The cluster analysis divided our sample into two clusters, showing different uptakes in grey, but also in white matter. These results demonstrate that AV-45 binding in white matter conveys subtle information not detectable using the SUVr approach. Although it is not more efficient than standard SUVr in discriminating AD patients from healthy subjects, this information could reveal white matter modifications. (orig.)

Gray matter changes in subjects at high risk for developing psychosis and first-episode schizophrenia: a voxel-based structural MRI study

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Kazue eNakamura

2013-03-01

Full Text Available Objectives: The aim of the present study was to use a voxel-based MRI method to investigate the neuroanatomical characteristics in subjects at high risk of developing psychosis compared with those of healthy controls and first-episode schizophrenia patients. Methods: This study included 14 subjects with at-risk mental state (ARMS, 34 patients with first-episode schizophrenia, and 51 healthy controls. We used voxel-based morphometry (VBM with the Diffeomorphic Anatomical Registration Through Exponentiated Lie Algebra (DARTEL tools to investigate the whole-brain difference in gray matter volume among the three groups. Results: Compared with the healthy controls, the schizophrenia patients showed significant gray matter reduction in the left anterior cingulate gyrus. There was no significant difference in the gray matter volume between the ARMS and other groups. Conclusion: The present study suggests that alteration of the anterior cingulate gyrus may be associated with development of frank psychosis. Further studies with a larger ARMS subjects would be required to examine the potential role of neuroimaging methods in the prediction of future transition into psychosis.

White matter organization in cervical spinal cord relates differently to age and control of grip force in healthy subjects.

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Lindberg, Påvel G; Feydy, Antoine; Maier, Marc A

2010-03-17

Diffusion tensor imaging (DTI) can be used to elucidate relations between CNS structure and function. We hypothesized that the degree of spinal white matter organization relates to the accuracy of control of grip force. Healthy subjects of different age were studied using DTI and visuomotor tracking of precision grip force. The latter is a prime component of manual dexterity. A regional analysis of spinal white matter [fractional anisotropy (FA)] across multiple cervical levels (C2-C3, C4-C5, and C6-C7) and in different regions of interest (left and right lateral or medial spinal cord) was performed. FA was highest at the C2-C3 level, higher on the right than the left side, and higher in the lateral than in the medial spinal cord (p level in the lateral spinal cord, in which the corticospinal tract innervates spinal circuitry controlling hand and digit muscles. FA of the medial spinal cord correlated consistently with age across all cervical levels, whereas FA of the lateral spinal cord did not. The results suggest (1) a functionally relevant specialization of lateral spinal cord white matter and (2) an increased sensitivity to age-related decline in medial spinal cord white matter in healthy subjects.

Improved motor sequence retention by motionless listening.

Science.gov (United States)

Lahav, Amir; Katz, Tal; Chess, Roxanne; Saltzman, Elliot

2013-05-01

This study examined the effect of listening to a newly learned musical piece on subsequent motor retention of the piece. Thirty-six non-musicians were trained to play an unfamiliar melody on a piano keyboard. Next, they were randomly assigned to participate in three follow-up listening sessions over 1 week. Subjects who, during their listening sessions, listened to the same initial piece showed significant improvements in motor memory and retention of the piece despite the absence of physical practice. These improvements included increased pitch accuracy, time accuracy, and dynamic intensity of key pressing. Similar improvements, though to a lesser degree, were observed in subjects who, during their listening sessions, were distracted by another task. Control subjects, who after learning the piece had listened to nonmusical sounds, showed impaired motoric retention of the piece at 1 week from the initial acquisition day. These results imply that motor sequences can be established in motor memory without direct access to motor-related information. In addition, the study revealed that the listening-induced improvements did not generalize to the learning of a new musical piece composed of the same notes as the initial piece learned, limiting the effects to musical motor sequences that are already part of the individual's motor repertoire.

[Exploration of a quantitative methodology to characterize the retention of PM2.5 and other atmospheric particulate matter by plant leaves: taking Populus tomentosa as an example].

Science.gov (United States)

Zhang, Zhi-Dan; Xi, Ben-Ye; Cao, Zhi-Guo; Jia, Li-Ming

2014-08-01

Taking Populus tomentosa as an example, a methodology called elution-weighing-particle size-analysis (EWPA) was proposed to evaluate quantitatively the ability of retaining fine particulate matter (PM2.5, diameter d ≤ 2.5 μm) and atmospheric particulate matter by plant leaves using laser particle size analyzer and balance. This method achieved a direct, accurate measurement with superior operability about the quality and particle size distribution of atmospheric particulate matter retained by plant leaves. First, a pre-experiment was taken to test the stability of the method. After cleaning, centrifugation and drying, the particulate matter was collected and weighed, and then its particle size distribution was analyzed by laser particle size analyzer. Finally, the mass of particulate matter retained by unit area of leaf and stand was translated from the leaf area and leaf area index. This method was applied to a P. tomentosa stand which had not experienced rain for 27 days in Beijing Olympic Forest Park. The results showed that the average particle size of the atmospheric particulate matter retained by P. tomentosa was 17.8 μm, and the volume percentages of the retained PM2.5, inhalable particulate matter (PM10, d ≤ 10 μm) and total suspended particle (TSP, d ≤ 100 μm) were 13.7%, 47.2%, and 99.9%, respectively. The masses of PM2.5, PM10, TSP and total particulate matter were 8.88 x 10(-6), 30.6 x 10(-6), 64.7 x 10(-6) and 64.8 x 10(-6) g x cm(-2) respectively. The retention quantities of PM2.5, PM10, TSP and total particulate matter by the P. tomentosa stand were 0.963, 3.32, 7.01 and 7.02 kg x hm(-2), respectively.

Subject Matter Specialists and Organizational Effectiveness of Krishi Vigyan Kendras of Tamil Nadu and Kerala

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Bimal Puthuparambil Bashir

2017-04-01

Full Text Available The study was undertaken with the objective of determining the socio-personal characteristics of Subject Matter Specialists (SMS of Krishi Vigyan Kendra (KVK and their relationship with organizational effectiveness. Altogether 65 SMS’ from 12 KVKs across Tamil Nadu and Kerala were selected. The study has concluded that most of respondents were middle aged with more than half of them being female. Majority of them was married, had work experience of below five years and had attended three to five trainings. Most of the respondents had high level of job satisfaction team-work and one-fourth felt a medium to high job stress. More than half of the respondents felt medium level of work load. There was a positive and significant correlation at one per cent level between job satisfaction / team work and organizational effectiveness of KVKs whereas job stress had a negative and significant correlation at five per cent level. Hence it may be concluded that team work, job satisfaction and job stress play a significant role in improving the organizational effectiveness of KVK. More emphasis must be given for team building enhance the job satisfaction level and reduce the job stress among Subject Matter Specialists of KVKs.

The Implementation of APIQ Creative Mathematics Game Method in the Subject Matter of Greatest Common Factor and Least Common Multiple in Elementary School

Science.gov (United States)

Rahman, Abdul; Saleh Ahmar, Ansari; Arifin, A. Nurani M.; Upu, Hamzah; Mulbar, Usman; Alimuddin; Arsyad, Nurdin; Ruslan; Rusli; Djadir; Sutamrin; Hamda; Minggi, Ilham; Awi; Zaki, Ahmad; Ahmad, Asdar; Ihsan, Hisyam

2018-01-01

One of causal factors for uninterested feeling of the students in learning mathematics is a monotonous learning method, like in traditional learning method. One of the ways for motivating students to learn mathematics is by implementing APIQ (Aritmetika Plus Intelegensi Quantum) creative mathematics game method. The purposes of this research are (1) to describe students’ responses toward the implementation of APIQ creative mathematics game method on the subject matter of Greatest Common Factor (GCF) and Least Common Multiple (LCM) and (2) to find out whether by implementing this method, the student’s learning completeness will improve or not. Based on the results of this research, it is shown that the responses of the students toward the implementation of APIQ creative mathematics game method in the subject matters of GCF and LCM were good. It is seen in the percentage of the responses were between 76-100%. (2) The implementation of APIQ creative mathematics game method on the subject matters of GCF and LCM improved the students’ learning.

On indexes and subject matter of “global competitiveness”

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A. V. Korotkov

2017-01-01

Full Text Available The aim of the research is to analyze the subject matter of a country’s competitiveness and to characterize statistical indexes of competitiveness known in the international practice from the perspective of a more elaborated theory of market competition. This aim follows from the identified problems. First, there are no generally accepted interpretation and joint understanding of competition and competitiveness at country level. Even the international organizations giving estimations of global competitiveness disagree on definitions of competitiveness. Secondly, there is no relation to the theory of market competition in the available source materials on competitiveness of the country without original methodology. Thirdly, well-known statistical indexes of global competitiveness do not have enough theoretical justification and differ in sets of factors. All this highlights the incompleteness of the methodology and methodological support of studying competitiveness at country level.Materials and methods. The research is based on the methodology of statistics, economic theory and marketing. The authors followed the basic principle of statistical methodology – requirement of continuous combination of qualitative and quantitative analysis, when the research begins and ends with qualitative analysis. A most important section of statistical methodology is widely used – construction of statistical indexes. In the course of the analysis, a method of statistical classifications is applied. A significant role in the present research is given to the method of generalizing and analogue method, realizing that related terms should mean similar and almost similar contents. Modeling of competition and competitiveness is widely used in the present research, which made it possible to develop a logical model of competition following from the competition theory.Results. Based on the definitions’ survey the analysis of the subject matter of global

Mobile Learning and Student Retention

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Bharat Inder Fozdar

2007-06-01

Full Text Available Student retention in open and distance learning (ODL is comparatively poor to traditional education and, in some contexts, embarrassingly low. Literature on the subject of student retention in ODL indicates that even when interventions are designed and undertaken to improve student retention, they tend to fall short. Moreover, this area has not been well researched. The main aim of our research, therefore, is to better understand and measure students’ attitudes and perceptions towards the effectiveness of mobile learning. Our hope is to determine how this technology can be optimally used to improve student retention at Bachelor of Science programmes at Indira Gandhi National Open University (IGNOU in India. For our research, we used a survey. Results of this survey clearly indicate that offering mobile learning could be one method improving retention of BSc students, by enhancing their teaching/ learning and improving the efficacy of IGNOU’s existing student support system. The biggest advantage of this technology is that it can be used anywhere, anytime. Moreover, as mobile phone usage in India explodes, it offers IGNOU easy access to a larger number of learners. This study is intended to help inform those who are seeking to adopt mobile learning systems with the aim of improving communication and enriching students’ learning experiences in their ODL institutions.

Habitual sleep durations and subjective sleep quality predict white matter differences in the human brain

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Sakh Khalsa

2017-06-01

Full Text Available Self-imposed short sleep durations are increasingly commonplace in society, and have considerable health and performance implications for individuals. Reduced sleep duration over multiple nights has similar behavioural effects to those observed following acute total sleep deprivation, suggesting that lack of sleep affects brain function cumulatively. A link between habitual sleep patterns and functional connectivity has previously been observed, and the effect of sleep duration on the brain's intrinsic functional architecture may provide a link between sleep status and cognition. However, it is currently not known whether differences in habitual sleep patterns across individuals are related to changes in the brain's white matter, which underlies structural connectivity. In the present study we use diffusion–weighted imaging and a group comparison application of tract based spatial statistics (TBSS to investigate changes to fractional anisotropy (FA and mean diffusivity (MD in relation to sleep duration and quality, hypothesising that white matter metrics would be positively associated with sleep duration and quality. Diffusion weighted imaging data was acquired from a final cohort of 33 (23–29 years, 10 female, mean 25.4 years participants. Sleep patterns were assessed for a 14 day period using wrist actigraphs and sleep diaries, and subjective sleep quality with the Pittsburgh Sleep Quality Index (PSQI. Median splits based on total sleep time and PSQI were used to create groups of shorter/longer and poorer/better sleepers, whose imaging data was compared using TBSS followed by post-hoc correlation analysis in regions identified as significantly different between the groups. There were significant positive correlations between sleep duration and FA in the left orbito-frontal region and the right superior corona radiata, and significant negative correlations between sleep duration and MD in right orbito-frontal white matter and the right

Transport and Retention of Colloids in Porous Media: Does Shape Really Matter?

Science.gov (United States)

The effect of particle shape on its transport and retention in porous media was evaluated by stretching carboxylate-modified fluorescent polystyrene spheres into rod shapes with aspect ratios of 2:1 and 4:1. Quartz crystal microbalance with dissipation experiments (QCM-D) were c...

Spatial targeting of conservation tillage to improve water quality and carbon retention benefits

International Nuclear Information System (INIS)

Yang, W.; Sheng, C.; Voroney, P.

2005-01-01

Conservation tillage reduces soil erosion and improves water quality in agricultural watersheds. However, the benefits of conservation tillage in carbon sequestration are the subject of controversy. Public funds are provided to farms to encourage the adoption of conservation tillage. Given the economic costs, the targeting of areas likely to achieve the greatest environmental benefits has become an important policy-making issue. A geographic information system (GIS) based modelling framework which integrated hydrologic, soil organic matter, and farm models to evaluate the spatial targeting of conservation tillage was presented. A case study applying the framework in the Fairchild Creek watershed in Ontario indicated that targeting conservation tillage based on sediment abatement goals can achieve comparable carbon retention benefits in terms of the percentage reduction of base carbon losses. Targeted subcatchments for conservation tillage varied across the watershed based on benefit to cost ratios. Conservation tillage patterns based on carbon retention goals showed similar results to sediment abatement goals but slight differences were observed because of different carbon content in the soils. The results indicated that sediment abatement may be used as an indicator in setting up program goals. The impacts of conservation programs can then be evaluated based on calibrated and validated hydrologic models in conjunction with monitoring data. Results also showed that setting carbon retention may lead to higher costs in order to achieve corresponding sediment abatement benefits. Carbon retention may not be suitable for setting as a stand-alone environmental goal for conservation programs because of the difficulties in verifying the impacts and the discrepancies between carbon and sediment benefits. It was concluded that the modelling results have important policy implications for the design of conservation stewardship programs that aim to achieve environmental

Retention of copper originating from different fungicides in contrasting soil types.

Science.gov (United States)

Komárek, Michael; Vanek, Ales; Chrastný, Vladislav; Száková, Jirina; Kubová, Karolina; Drahota, Petr; Balík, Jirí

2009-07-30

This work described the retention of Cu from two different commonly used pesticides, the Bordeaux mixture (CuSO(4)+Ca(OH)(2)) and Cu-oxychloride (3Cu(OH)(2).CuCl(2)), and from Cu(NO(3))(2) in contrasting soil types (Leptosol, Chernozem, Cambisol). Thermodynamic modeling showed that Cu speciation was similar in all fungicide solutions. However, the retention of Cu differed with the fungicide used (maximum retention from the Bordeaux mixture) which indicates that different retention processes occurred in the studied soils. The suggested mechanisms include: specific and non-specific adsorption (especially on soil organic matter), precipitation of newly formed phases, such as CuO, Cu(OH)(2), Cu(2)(OH)(3)NO(3), CuCO(3)/Cu(2)(OH)(2)CO(3) and in the case of the Bordeaux mixture, precipitation of various Cu-hydroxysulfates. These phases were identified by the speciation model. The retention of fungicide-derived Cu in the studied soil types followed well the Freundlich isotherm and was directly controlled by the chemical form of Cu. This fact should be taken into account for both environmental and practical applications.

Retention of copper originating from different fungicides in contrasting soil types

Energy Technology Data Exchange (ETDEWEB)

Komarek, Michael, E-mail: komarek@af.czu.cz [Department of Agro-Environmental Chemistry and Plant Nutrition, Czech University of Life Sciences Prague, Kamycka 129, 165 21, Prague 6 (Czech Republic); Vanek, Ales [Department of Soil Science and Soil Protection, Czech University of Life Sciences Prague, Kamycka 129, 165 21, Prague 6 (Czech Republic); Chrastny, Vladislav [Department of Applied Chemistry, University of South Bohemia, Studentska 13, 370 05, Ceske Budejovice (Czech Republic); Szakova, Jirina; Kubova, Karolina [Department of Agro-Environmental Chemistry and Plant Nutrition, Czech University of Life Sciences Prague, Kamycka 129, 165 21, Prague 6 (Czech Republic); Drahota, Petr [Institute of Geochemistry, Mineralogy and Mineral Resources, Charles University Prague, Albertov 6, 128 43, Prague 2 (Czech Republic); Balik, Jiri [Department of Agro-Environmental Chemistry and Plant Nutrition, Czech University of Life Sciences Prague, Kamycka 129, 165 21, Prague 6 (Czech Republic)

2009-07-30

This work described the retention of Cu from two different commonly used pesticides, the Bordeaux mixture (CuSO{sub 4} + Ca(OH){sub 2}) and Cu-oxychloride (3Cu(OH){sub 2}.CuCl{sub 2}), and from Cu(NO{sub 3}){sub 2} in contrasting soil types (Leptosol, Chernozem, Cambisol). Thermodynamic modeling showed that Cu speciation was similar in all fungicide solutions. However, the retention of Cu differed with the fungicide used (maximum retention from the Bordeaux mixture) which indicates that different retention processes occurred in the studied soils. The suggested mechanisms include: specific and non-specific adsorption (especially on soil organic matter), precipitation of newly formed phases, such as CuO, Cu(OH){sub 2}, Cu{sub 2}(OH){sub 3}NO{sub 3}, CuCO{sub 3}/Cu{sub 2}(OH){sub 2}CO{sub 3} and in the case of the Bordeaux mixture, precipitation of various Cu-hydroxysulfates. These phases were identified by the speciation model. The retention of fungicide-derived Cu in the studied soil types followed well the Freundlich isotherm and was directly controlled by the chemical form of Cu. This fact should be taken into account for both environmental and practical applications.

Retention of copper originating from different fungicides in contrasting soil types

International Nuclear Information System (INIS)

Komarek, Michael; Vanek, Ales; Chrastny, Vladislav; Szakova, Jirina; Kubova, Karolina; Drahota, Petr; Balik, Jiri

2009-01-01

This work described the retention of Cu from two different commonly used pesticides, the Bordeaux mixture (CuSO 4 + Ca(OH) 2 ) and Cu-oxychloride (3Cu(OH) 2 .CuCl 2 ), and from Cu(NO 3 ) 2 in contrasting soil types (Leptosol, Chernozem, Cambisol). Thermodynamic modeling showed that Cu speciation was similar in all fungicide solutions. However, the retention of Cu differed with the fungicide used (maximum retention from the Bordeaux mixture) which indicates that different retention processes occurred in the studied soils. The suggested mechanisms include: specific and non-specific adsorption (especially on soil organic matter), precipitation of newly formed phases, such as CuO, Cu(OH) 2 , Cu 2 (OH) 3 NO 3 , CuCO 3 /Cu 2 (OH) 2 CO 3 and in the case of the Bordeaux mixture, precipitation of various Cu-hydroxysulfates. These phases were identified by the speciation model. The retention of fungicide-derived Cu in the studied soil types followed well the Freundlich isotherm and was directly controlled by the chemical form of Cu. This fact should be taken into account for both environmental and practical applications.

Patterns of 11C-PIB cerebral retention in mild cognitive impairment patients.

Science.gov (United States)

Banzo, I; Jiménez-Bonilla, J F; Martínez-Rodríguez, I; Quirce, R; de Arcocha-Torres, M; Bravo-Ferrer, Z; Lavado-Pérez, C; Sánchez-Juan, P; Rodríguez, E; Jiménez-Alonso, M; López-Defilló, J; Carril, J M

2016-01-01

To evaluate the patterns of cerebral cortical distribution of (11)C-PIB in patients with mild cognitive impairment (MCI). The study included 69 patients (37 male, age range 42-79 years) with MCI, sub-classified as 53 with amnestic-MCI (A-MCI), and 16 with non-amnestic-MCI (NA-MCI). Patients underwent (11)C-PIB PET/CT scan 60min after intravenous injection of the radiotracer. A visual analysis of the images was performed by 2 experienced physicians. (11)C-PIB-positive studies were considered when gray matter uptake was equal to or greater than white matter. According to the regions involved, (11)C-PIB-positive studies were classified into A-pattern (predominant retention in frontal, anterior cingulate, lateral temporal, and basal ganglia) and B-pattern (generalized retention). Thirty-nine of the 69 (56%) patients with MCI showed (11)C-PIB retention. Of the 53 A-MCI patients, 36 (68%) showed (11)C-PIB retention. Eleven out of 36 (30%) positive scans in A-MCI patients showed A-pattern, and 25 out of 36 (70%) patients had a B-pattern. Positive (11)C-PIB was observed in 3 out of 16 (19%) patients with NA-MCI. Regional distribution in these 3 patients showed A-pattern in 1, and B-pattern in 2 patients. Cortical retention of (11)C-PIB was more frequent in A-MCI than in NA-MCI patients, and also B-pattern than A-pattern in the (11)C-PIB positive group. The recognition of (11)C-PIB distribution patterns allows MCI patients to be classified, and the A-pattern may offer a therapeutic window for potential future treatments. Copyright © 2015 Elsevier España, S.L.U. and SEMNIM. All rights reserved.

Gray matter and white matter abnormalities in online game addiction

Energy Technology Data Exchange (ETDEWEB)

Weng, Chuan-Bo, E-mail: send007@163.com [Department of Neurosurgery, Anhui Provincial Hospital Affiliated to Anhui Medical University, 17 Lujiang Road, Hefei, Ahui Province 230001 (China); School of Neurosurgery, Anhui Medical University, 81 Meishang Road, Hefei, Anhui Province 230032 (China); Qian, Ruo-Bing, E-mail: rehomail@163.com [Department of Neurosurgery, Anhui Provincial Hospital Affiliated to Anhui Medical University, 17 Lujiang Road, Hefei, Ahui Province 230001 (China); Anhui Provincial Institute of Stereotactic Neurosurgery, 9 Lujiang Road, Hefei, Ahui Province 230001 (China); Fu, Xian-Ming, E-mail: 506537677@qq.com [Department of Neurosurgery, Anhui Provincial Hospital Affiliated to Anhui Medical University, 17 Lujiang Road, Hefei, Ahui Province 230001 (China); Anhui Provincial Institute of Stereotactic Neurosurgery, 9 Lujiang Road, Hefei, Ahui Province 230001 (China); Lin, Bin, E-mail: 274722758@qq.com [School of Neurosurgery, Anhui Medical University, 81 Meishang Road, Hefei, Anhui Province 230032 (China); Han, Xiao-Peng, E-mail: hanxiaopeng@163.com [Department of Psychology, Anhui Provincial Hospital Affiliated to Anhui Medical University, 17 Lujiang Road, Hefei, Ahui Province 230001 (China); Niu, Chao-Shi, E-mail: niuchaoshi@163.com [Department of Neurosurgery, Anhui Provincial Hospital Affiliated to Anhui Medical University, 17 Lujiang Road, Hefei, Ahui Province 230001 (China); Anhui Provincial Institute of Stereotactic Neurosurgery, 9 Lujiang Road, Hefei, Ahui Province 230001 (China); Wang, Ye-Han, E-mail: wangyehan@163.com [Department of Neurosurgery, Anhui Provincial Hospital Affiliated to Anhui Medical University, 17 Lujiang Road, Hefei, Ahui Province 230001 (China); Anhui Provincial Institute of Stereotactic Neurosurgery, 9 Lujiang Road, Hefei, Ahui Province 230001 (China)

2013-08-15

Online game addiction (OGA) has attracted greater attention as a serious public mental health issue. However, there are only a few brain magnetic resonance imaging studies on brain structure about OGA. In the current study, we used voxel-based morphometry (VBM) analysis and tract-based spatial statistics (TBSS) to investigate the microstructural changes in OGA and assessed the relationship between these morphology changes and the Young's Internet Addiction Scale (YIAS) scores within the OGA group. Compared with healthy subjects, OGA individuals showed significant gray matter atrophy in the right orbitofrontal cortex, bilateral insula, and right supplementary motor area. According to TBSS analysis, OGA subjects had significantly reduced FA in the right genu of corpus callosum, bilateral frontal lobe white matter, and right external capsule. Gray matter volumes (GMV) of the right orbitofrontal cortex, bilateral insula and FA values of the right external capsule were significantly positively correlated with the YIAS scores in the OGA subjects. Our findings suggested that microstructure abnormalities of gray and white matter were present in OGA subjects. This finding may provide more insights into the understanding of the underlying neural mechanisms of OGA.

Gray matter and white matter abnormalities in online game addiction

International Nuclear Information System (INIS)

Weng, Chuan-Bo; Qian, Ruo-Bing; Fu, Xian-Ming; Lin, Bin; Han, Xiao-Peng; Niu, Chao-Shi; Wang, Ye-Han

2013-01-01

Online game addiction (OGA) has attracted greater attention as a serious public mental health issue. However, there are only a few brain magnetic resonance imaging studies on brain structure about OGA. In the current study, we used voxel-based morphometry (VBM) analysis and tract-based spatial statistics (TBSS) to investigate the microstructural changes in OGA and assessed the relationship between these morphology changes and the Young's Internet Addiction Scale (YIAS) scores within the OGA group. Compared with healthy subjects, OGA individuals showed significant gray matter atrophy in the right orbitofrontal cortex, bilateral insula, and right supplementary motor area. According to TBSS analysis, OGA subjects had significantly reduced FA in the right genu of corpus callosum, bilateral frontal lobe white matter, and right external capsule. Gray matter volumes (GMV) of the right orbitofrontal cortex, bilateral insula and FA values of the right external capsule were significantly positively correlated with the YIAS scores in the OGA subjects. Our findings suggested that microstructure abnormalities of gray and white matter were present in OGA subjects. This finding may provide more insights into the understanding of the underlying neural mechanisms of OGA

Gray matter and white matter abnormalities in online game addiction.

Science.gov (United States)

Weng, Chuan-Bo; Qian, Ruo-Bing; Fu, Xian-Ming; Lin, Bin; Han, Xiao-Peng; Niu, Chao-Shi; Wang, Ye-Han

2013-08-01

Online game addiction (OGA) has attracted greater attention as a serious public mental health issue. However, there are only a few brain magnetic resonance imaging studies on brain structure about OGA. In the current study, we used voxel-based morphometry (VBM) analysis and tract-based spatial statistics (TBSS) to investigate the microstructural changes in OGA and assessed the relationship between these morphology changes and the Young's Internet Addiction Scale (YIAS) scores within the OGA group. Compared with healthy subjects, OGA individuals showed significant gray matter atrophy in the right orbitofrontal cortex, bilateral insula, and right supplementary motor area. According to TBSS analysis, OGA subjects had significantly reduced FA in the right genu of corpus callosum, bilateral frontal lobe white matter, and right external capsule. Gray matter volumes (GMV) of the right orbitofrontal cortex, bilateral insula and FA values of the right external capsule were significantly positively correlated with the YIAS scores in the OGA subjects. Our findings suggested that microstructure abnormalities of gray and white matter were present in OGA subjects. This finding may provide more insights into the understanding of the underlying neural mechanisms of OGA. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Processes controlling the production of aromatic water-soluble organic matter during litter decomposition

NARCIS (Netherlands)

Klotzbücher, T.; Kaiser, K.; Filley, T.R.; Kalbitz, K.

2013-01-01

Dissolved organic matter (DOM) plays a fundamental role for many soil processes. For instance, production, transport, and retention of DOM control properties and long-term storage of organic matter in mineral soils. Production of water-soluble compounds during the decomposition of plant litter is a

Enhancing retention of partial dentures using elastomeric retention rings

Directory of Open Access Journals (Sweden)

Kakkirala Revathi

2015-01-01

Full Text Available This report presents an alternative method for the retention of partial dentures that relies on the engagement of tooth undercuts by a lining material. The lab procedures are also presented. A new maxillary and mandibular acrylic partial dentures were fabricated using elastomeric retention technique for a partially dentate patient. A partially dentate man reported difficulty in retaining his upper removable partial denture (RPD. The maxillary RPD was designed utilizing elastomeric retention technique. During follow-up, it was necessary to replace the retention rings due to wear. The replacement of the retention rings, in this case, was done through a chairside reline technique. Elastomeric retention technique provides exceptionally good retention can be indicated to stabilize, cushion, splint periodontally involved teeth, no enough undercut for clasps, eliminate extractions, single or isolated teeth.

Subjective or objective? What matters?

Czech Academy of Sciences Publication Activity Database

Sunega, Petr

2014-01-01

Roč. 1, č. 1 (2014), s. 35-43 ISSN 2336-2839 R&D Projects: GA ČR(CZ) GAP404/12/1446 Institutional support: RVO:68378025 Keywords : comparative housing policy * globalisation Subject RIV: AO - Sociology, Demography

An investigation of the leaf retention capacity, efficiency and mechanism for atmospheric particulate matter of five greening tree species in Beijing, China.

Science.gov (United States)

Liu, Jinqiang; Cao, Zhiguo; Zou, Songyan; Liu, Huanhuan; Hai, Xiao; Wang, Shihua; Duan, Jie; Xi, Benye; Yan, Guangxuan; Zhang, Shaowei; Jia, Zhongkui

2018-03-01

Urban trees have the potential to reduce air pollution, but the retention capacity and efficiency of different tree species for atmospheric particulate matter (PM) accumulation and the underlying mechanism hasn't been well understood. To select tree species with high air purification abilities, the supplementing ultrasonic cleaning (UC) procedure was first introduced into the conventional leaf cleaning methods [single water cleaning (WC) or plus brush cleaning (BC)] for eluting the leaf-retained PM. Further updates to the methodology were applied to investigate the retention capacity, efficiency, and mechanism for PM of five typical greening tree species in Beijing, China. Meanwhile, the particle size distribution of PM on the leaves, the PM retention efficiencies of easily removable (ERP), difficult-to-remove (DRP) and totally removable (TRP) particles on the leaf (AE leaf ), and the individual tree scales were estimated. The experimental leaf samples were collected from trees with similar sizes 4 (SDR) and 14days (LDR) after rainfall. When the leaves were cleaned by WC+BC, there was, on average, 29%-46% of the PM remaining on the leaves of different species, which could be removed almost completely if UC was supplemented. From SDR to LDR, the mass of the leaf-retained PM increased greatly, and the particle size distribution changed markedly for all species except for Sophorajaponica. Pinus tabuliformis retains particles with the largest average diameter (34.2μm), followed by Ginkgo biloba (20.5μm), Sabina chinensis (16.4μm), Salix babylonica (16.0μm), and S. japonica (13.1μm). S. japonica and S. chinensis had the highest AE leaf to retain the TRP and ERP of both PM 1 and PM 1-2.5 , respectively. Conversely, S. babylonica and P. tabuliformis could retain both TRP and ERP of PM 2.5-5 and PM 5-10 , and PM >10 and TSP with the highest AE leaf , respectively. In conclusion, our results could be useful in selecting greening tree species with high air purification

Retention of U(VI) onto silica in presence of model organic molecules

International Nuclear Information System (INIS)

Pham, T.T.H.; Mercier-Bion, F.; Drot, R.; Lagarde, G.; Simoni, E.; Lambert, J.

2008-01-01

It is well-known that the organic matter influences the retention of ions onto mineral surfaces. However, the major part of concerned studies implies humic substances and complex solids. Another approach for identifying the sorption mechanisms is possible by studying simpler solids than those present in natural medium. So, silica is chosen as mineral surface because of its abundance in soils and of the presence of Si-O groups in clayey minerals. Uranium (VI) is selected as cation. Simple organic molecules like acetic (one carboxylic group) and oxalic (two carboxylic functions) acids are considered as models of the natural organic matter for understanding their role in the retention of U(VI) onto powders and slides of silica. Binary (organics/silica, U(VI)/silica) and ternary systems (organics/silica/U(VI)) are studied by complementary approaches. Sorption edges as function of pH are obtained by liquid scintillation methods and capillary electrophoresis. Different spectroscopic techniques are used to deduce the interactions between the organic matter and U(VI) sorbed onto the silica whose: Time-Resolved Laser induced Fluorescence Spectroscopy (TRLFS), X-ray Photoelectron Spectroscopy (XPS), Nuclear Microprobe Analysis (NMA). The results of the effect of these model organic molecules onto the U(VI) retention showed a good agreement between the different techniques. Concerning the acetic acid, there are not differences in the sorption percentages of uranyl (see the figure). All these results indicate that the uranyl-acetate complexes stay in the aqueous solution rather than sorbing onto the silica. On the contrary, oxalic acid influences the sorption of U(VI) onto the silica surface. The sorption percentage of U(VI) in the ternary system (oxalic acid/silica/U(VI)) is lower than the binary system (U(VI)/silica) (see the figure). So, the presence of oxalic acid decreases the sorption of U(VI) onto the silica surface. (authors)

A more randomly organized grey matter network is associated with deteriorating language and global cognition in individuals with subjective cognitive decline.

Science.gov (United States)

Verfaillie, Sander C J; Slot, Rosalinde E R; Dicks, Ellen; Prins, Niels D; Overbeek, Jozefien M; Teunissen, Charlotte E; Scheltens, Philip; Barkhof, Frederik; van der Flier, Wiesje M; Tijms, Betty M

2018-03-30

Grey matter network disruptions in Alzheimer's disease (AD) are associated with worse cognitive impairment cross-sectionally. Our aim was to investigate whether indications of a more random network organization are associated with longitudinal decline in specific cognitive functions in individuals with subjective cognitive decline (SCD). We included 231 individuals with SCD who had annually repeated neuropsychological assessment (3 ± 1 years; n = 646 neuropsychological investigations) available from the Amsterdam Dementia Cohort (54% male, age: 63 ± 9, MMSE: 28 ± 2). Single-subject grey matter networks were extracted from baseline 3D-T1 MRI scans and we computed basic network (size, degree, connectivity density) and higher-order (path length, clustering, betweenness centrality, normalized path length [lambda] and normalized clustering [gamma]) parameters at whole brain and/or regional levels. We tested associations of network parameters with baseline and annual cognition (memory, attention, executive functioning, language composite scores, and global cognition [all domains with MMSE]) using linear mixed models, adjusted for age, sex, education, scanner and total gray matter volume. Lower network size was associated with steeper decline in language (β ± SE = 0.12 ± 0.05, p organized grey matter network was associated with a steeper decline of cognitive functioning, possibly indicating the start of cognitive impairment. © 2018 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.

Knot numbers used as labels for identifying subject matter of a khipu

Directory of Open Access Journals (Sweden)

Alberto Saez-Rodriguez

2013-03-01

Full Text Available This investigation presents a new way to look at the numerical khipu, a knotted-string recording device from Pachacamac (Peru, and the types of information it contains. In addition to celestial coordinates, khipu knots apparently pertain to an early form of double-entry accounting. This study hypothesizes that the khipu sample has the recording capacity needed to register double-entry-like accounts. After the identification of its subject matter, the khipu sample was studied in an attempt to ascertain whether the knot values could represent instructions from the Inca state administration to a local accounting center. The results indicate that the numerical information in the pairing quadrants (determined by the distribution of S- and Z-knots should be read from top to bottom along the full length of the string and can then provide certain complementary details regarding the projected corn stocks of the Inca stat

Fractional intestinal absorption and retention of calcium measured by whole-body counting. Application of a power function model

International Nuclear Information System (INIS)

Pors Nielsen, S.; Baerenholdt, O.; Munck, O.

1975-01-01

By application of a power function model, fractional intestinal calcium absorption was investigated with a new technique involving whole-body counting after successive oral and intravenous administration of standard doses of 47 Ca. The fractional calcium retention 7 days after the oral load of 47 Ca was also measured. Fractional calcium retention averaged 30.3% in normal subjects and 11.5% in 11 patients with intestinal malabsorption. In the same groups fractional calcium absorption averaged 46.6% and 16.4%, respectively. Fractional calcium retention and intestinal calcium absorption were significantly correlated to body surface area, and there was a well-defined relation between fractional retention and absorption of calcium. These studies demonstrate that measurements of fractional retention and fractional intestinal absorption of calcium can be combined by the use of a whole-body counter, that fractional retention and intestinal absorption are proportional to total body surface area and therefore probably also to the total bone mass, and that fractional retention and absorption are so closely interrelated that frational absorption can be estimated from fractional retention with reasonable accuracy in normal subjects. (auth.)

Apparent mineral retention is similar in control and hyperinsulinemic men after consumption of high amylose cornstarch.

Science.gov (United States)

Behall, Kay M; Howe, Juliette C; Anderson, Richard A

2002-07-01

The effects on apparent mineral retention after long-term consumption of a high amylose diet containing 30 g resistant starch (RS) were investigated in 10 control and 14 hyperinsulinemic men. Subjects consumed products (bread, muffins, cookies, corn flakes and cheese puffs) made with standard (70% amylopectin, 30% amylose; AP) or high amylose (70% amylose, 30% amylopectin; AM) cornstarch for two 14-wk periods in a crossover pattern. Starch products replaced usual starches in the habitual diet for 10 wk followed by 4 wk of consuming the controlled diets. During wk 12, all urine, feces and duplicate foods were collected for 7 d. Urinary chromium losses after a glucose tolerance test or 24-h collections of the hyperinsulinemic and control subjects did not differ and were not altered by diet. Except for zinc, the two subject types did not differ significantly in apparent mineral balance. Apparent retentions of calcium and magnesium were not significantly affected by diet (AM vs. AP) or type-by-diet interaction. Apparent iron retention tended to be greater after AM than AP consumption (P copper retention was greater after consuming AP than after AM (P < 0.02), whereas apparent zinc retention was greater after consuming AM than after AP (P < 0.018). Zinc also showed a significant type-by-diet interaction (P < 0.034) with control subjects retaining less zinc after consuming AP than after AM. In summary, a high amylose cornstarch diet containing 30 g RS could be consumed long term without markedly affecting, and possibly enhancing, retention of some minerals.

Middle-School Teachers' Understanding and Teaching of the Engineering Design Process: A Look at Subject Matter and Pedagogical Content Knowledge

Science.gov (United States)

Hynes, Morgan M.

2012-01-01

This paper reports on research investigating six middle school teachers without engineering degrees as they taught an engineering unit on the engineering design process. Videotaped classroom sessions and teacher interviews were analyzed to understand the subject matter and pedagogical content knowledge the teachers used and developed as they…

The Knowledge Base of Subject Matter Experts in Teaching: A Case Study of a Professional Scientist as a Beginning Teacher

Science.gov (United States)

Diezmann, Carmel M.; Watters, James J.

2015-01-01

One method of addressing the shortage of science and mathematics teachers is to train scientists and other science-related professionals to become teachers. Advocates argue that as discipline experts these career changers can relate the subject matter knowledge to various contexts and applications in teaching. In this paper, through interviews and…

Families Matter! Presexual Risk Prevention Intervention

Science.gov (United States)

Lasswell, Sarah M.; Riley, Drewallyn B.; Poulsen, Melissa N.

2013-01-01

Parent-based HIV prevention programming may play an important role in reaching youths early to help establish lifelong patterns of safe and healthy sexual behaviors. Families Matter! is a 5-session, evidence-based behavioral intervention designed for primary caregivers of children aged 9 to 12 years to promote positive parenting and effective parent–child communication about sexuality and sexual risk reduction. The program’s 5-step capacity-building model was implemented with local government, community, and faith-based partners in 8 sub-Saharan African countries with good intervention fidelity and high levels of participant retention. Families Matter! may be useful in other resource-constrained settings. PMID:24028229

Influence of PBL with open-book tests on knowledge retention measured with progress tests

NARCIS (Netherlands)

Heijne-Penninga, M.; Kuks, J. B. M.; Hofman, W. H. A.; Muijtjens, A. M. M.; Cohen-Schotanus, J.

The influence of problem-based learning (PBL) and open-book tests on long-term knowledge retention is unclear and subject of discussion. Hypotheses were that PBL as well as open-book tests positively affect long-term knowledge retention. Four progress test results of fifth and sixth-year medical

Exploring the Relationship between Secondary Science Teachers' Subject Matter Knowledge and Knowledge of Student Conceptions While Teaching Evolution by Natural Selection

Science.gov (United States)

Lucero, Margaret M.; Petrosino, Anthony J.; Delgado, Cesar

2017-01-01

The fundamental scientific concept of evolution occurring by natural selection is home to many deeply held alternative conceptions and considered difficult to teach. Science teachers' subject matter knowledge (SMK) and the pedagogical content knowledge (PCK) component of knowledge of students' conceptions (KOSC) can be valuable resources for…

Climatic variability and its role in regulating C, N and P retention in the James River Estuary

Science.gov (United States)

Bukaveckas, Paul A.; Beck, Michael; Devore, Dana; Lee, William M.

2018-05-01

Transformations and retention of C, N and P inputs to estuaries are subject to external factors such as discharge-driven variation in loading rates, and internal processes regulating biogeochemical cycles. We used an 8-year time series of finely resolved (monthly) mass balances for the tidal freshwater segment of the James River Estuary to assess the influence of discharge and temperature on C, N and P retention. Peak export and retention of organic, likely particulate, fractions occurred in months of highest discharge. With increasing discharge we observed higher mass retention, greater proportional retention (in relation to inputs) and more selective retention (with P retained preferentially over N and C). DIN retention was strongly influenced by water temperature with 10-fold high retention occurring at high (>20 °C) vs. low (estuaries is in dissolved inorganic form, and therefore subject to temperature dependent rates of biological assimilation and denitrification. By contrast, the bulk of the P load was in particulate form, which is retained via sediment trapping, and not appreciably affected by water temperature. The tidal freshwater estuary was an important site for nutrient removal where the accumulation of N- and P- rich materials may delay recovery in response to nutrient load reductions.

Atrophy of gray and white matters in the brain during aging

International Nuclear Information System (INIS)

Takeda, Shumpei; Matsuzawa, Taiju; Ito, Hisao.

1984-01-01

We studied atrophy of gray and white matter during aging in 57 males and 44 females with no neurological disturbances using x-ray computed tomography. The ages ranged from 12 to 80 years. Brain atrophy was expressed as brain volume index: 100% x [(brain volume/cranial cavity volume) in individual subjects]/[(brain volume/cranial cavity volume) in normal subjects of 20-39 years]. Atrophy of gray and white matter volume was expressed as gray and white matter volume indices: 100% x (apparent gray or white matter volume index in individual subjects)/(apparent gray or white matter volume index in normal subjects whose brain volume index was greater than 98%), where apparent gray and white matter volume indices were expressed as 100% x [(gray or white matter volume/cranial cavity volume) in individual subjects]/[(gray or white matter volume/cranial cavity volume) in normal subjects of 20-39 years]. Both the gray and white matter volume indices changed proportionally to the brain volume index (p<0.001). As the brain atrophy advanced, the gray matter volume index decreased more than the white matter volume index (P<0.001). Decrease in the gray and white matter volume indices was statistically significant only in seventies (P<0.002 for gray matter, P<0.05 for white matter). (author)

ASSOCIATIVE EFFECT OF MOLASSES-UREA BLOCK AND FORAGE QUALITY ON NUTRIENT DIGESTION AND NITROGEN RETENTION IN SHEEP

Directory of Open Access Journals (Sweden)

lqbal Saeed. M. M. Siddiqui and G. I. Habib

2002-01-01

Full Text Available A study was conducted in a 4x4 Latin square design involving four adult crossbred (Kaghani x Rambouillet weather kept in individual metabolic crates and four experimental diets viz: maize stovers (Diet A, maize stovers with 150 g/d molasses-urea block (Diet B, lucerne hay (Diet Cand lucerne hay with 150 g/d molasses-urea block (Diet D. The forage intake was restricted to 2% of body weight. Each experimental period consisted 10 days of adaptation followed by five days of data collection. Total dry matter intake on molasses-urea block (MUB supplemented diets was higher (p<0.05 than unsupplemented diets. The daily quantity of total dry matter and water consumed by weathers was higher (p < 0.001 on MUB supplemented diets. Water consumption was positively co-related to nitrogen intake (r2 0.66: p< 0.00 I and varied due to diets (p < 0.00 I. in vivo dry matter digestibility (DMD and organic matter digestibility (OMD of lucerne hay-based diets were greater (P< 005 than those containing maize stovers. Supplementation of MUB did not affect the DMD or OMD of the diets. The interaction of MUB and forage (P = 0.06 revealed that MUB was effective in increasing (P< 0.05 the nitrogen digestibility of maize stovers from 30,59% on diet A to 51.33% on diet B but did not affect the nitrogen digestibility in animals fed lucerne hay. The wethers receiving lucerne hay-based diets retained more nitrogen (p< 0.001 than those given maize stovers (8.50 's 3,12 g/d. Molasses-urea block supplementation on both forages increased (p < 0.05 the nitrogen retention. Mean nitrogen retention was I 82. 4.41, 7 .19 and 9.82 gld in wethers receiving diets A. B. C and D. respectively. Mean rumen ammonia concentration (mg N/lOO ml in wethers receiving maize stovers. was 10.52. which increased (p< 0,05 to 17.87 in response to MUB supplementation. On lucerne hay. the rumen ammonia concentrations did not change due to MUB and the mean values on diets C and D were 24,24 and 29.88 mg N/100

NASA’s Universe of Learning: Engaging Subject Matter Experts to Support Museum Alliance Science Briefings

Science.gov (United States)

Marcucci, Emma; Slivinski, Carolyn; Lawton, Brandon L.; Smith, Denise A.; Squires, Gordon K.; Biferno, Anya A.; Lestition, Kathleen; Cominsky, Lynn R.; Lee, Janice C.; Rivera, Thalia; Walker, Allyson; Spisak, Marilyn

2018-06-01

NASA's Universe of Learning creates and delivers science-driven, audience-driven resources and experiences designed to engage and immerse learners of all ages and backgrounds in exploring the universe for themselves. The project is a unique partnership between the Space Telescope Science Institute, Caltech/IPAC, Jet Propulsion Laboratory, Smithsonian Astrophysical Observatory, and Sonoma State University and is part of the NASA SMD Science Activation Collective. The NASA’s Universe of Learning projects pull on the expertise of subject matter experts (scientist and engineers) from across the broad range of NASA Astrophysics themes and missions. One such project, which draws strongly on the expertise of the community, is the NASA’s Universe of Learning Science Briefings, which is done in collaboration with the NASA Museum Alliance. This collaboration presents a monthly hour-long discussion on relevant NASA astrophysics topics or events to an audience composed largely of informal educators from informal learning environments. These professional learning opportunities use experts and resources within the astronomical community to support increased interest and engagement of the informal learning community in NASA Astrophysics-related concepts and events. Briefings are designed to create a foundation for this audience using (1) broad science themes, (2) special events, or (3) breaking science news. The NASA’s Universe of Learning team engages subject matter experts to be speakers and present their science at these briefings to provide a direct connection to NASA Astrophysics science and provide the audience an opportunity to interact directly with scientists and engineers involved in NASA missions. To maximize the usefulness of the Museum Alliance Science Briefings, each briefing highlights resources related to the science theme to support informal educators in incorporating science content into their venues and/or interactions with the public. During this

Contrast between white and grey matter: MRI appearance with ageing

International Nuclear Information System (INIS)

Magnaldi, S.; Ukmar, M.; Vasciaveo, A.; Longo, R.; Pozzi-Mucelli, R.S.

1993-01-01

MRI contrast between white and grey matter appears to be higher in young normal subjects than in older patients. The aim of the present study was to investigate the possible relationships between these changes in contrast and ageing. It consisted of two parts. In the first part we retrospectively evaluated 140 MRI brain examinations of healthy subjects, 20 per decade (age range 20-90 years), in whom the contrast was subjectively scored. In the second part we prospectively measured the actual T1, spin density (SD) and T2 values of white and grey matter in another 22 healthy subjects (age range 20-80 years). In the first group of subjects a progressive decrease in white/grey matter contrast was observed with ageing. In the second group of subjects the T1, SD and T2 values of white matter were always shorter than those of grey matter. There is a close relation among T1, SD and T2 values of white and grey matter with ageing. We suggest that there is a progressive loss of white/grey matter contrast with ageing. Such a phenomenon is possibly due to an increased water content in the white matter and the progressive neuronal loss in the grey matter that occurs with age. (orig.)

A Case Study of Beginning Science Teachers' Subject Matter (SMK) and Pedagogical Content Knowledge (PCK) of Teaching Chemical Reaction in Turkey

Science.gov (United States)

Usak, Muhammet; Ozden, Mustafa; Eilks, Ingo

2011-01-01

This paper describes a case study focusing on the subject matter knowledge, pedagogical content knowledge, and beliefs about science teaching of student teachers in Turkey at the start of their university education. The topic of interest was that of teaching chemical reactions in secondary chemistry education. A written test was developed which…

Pedotransfer functions to estimate water retention parameters of soils in northeastern Brazil

Directory of Open Access Journals (Sweden)

Alexandre Hugo Cezar Barros

2013-04-01

Full Text Available Pedotransfer functions (PTF were developed to estimate the parameters (α, n, θr and θs of the van Genuchten model (1980 to describe soil water retention curves. The data came from various sources, mainly from studies conducted by universities in Northeast Brazil, by the Brazilian Agricultural Research Corporation (Embrapa and by a corporation for the development of the São Francisco and Parnaíba river basins (Codevasf, totaling 786 retention curves, which were divided into two data sets: 85 % for the development of PTFs, and 15 % for testing and validation, considered independent data. Aside from the development of general PTFs for all soils together, specific PTFs were developed for the soil classes Ultisols, Oxisols, Entisols, and Alfisols by multiple regression techniques, using a stepwise procedure (forward and backward to select the best predictors. Two types of PTFs were developed: the first included all predictors (soil density, proportions of sand, silt, clay, and organic matter, and the second only the proportions of sand, silt and clay. The evaluation of adequacy of the PTFs was based on the correlation coefficient (R and Willmott index (d. To evaluate the PTF for the moisture content at specific pressure heads, we used the root mean square error (RMSE. The PTF-predicted retention curve is relatively poor, except for the residual water content. The inclusion of organic matter as a PTF predictor improved the prediction of parameter a of van Genuchten. The performance of soil-class-specific PTFs was not better than of the general PTF. Except for the water content of saturated soil estimated by particle size distribution, the tested models for water content prediction at specific pressure heads proved satisfactory. Predictions of water content at pressure heads more negative than -0.6 m, using a PTF considering particle size distribution, are only slightly lower than those obtained by PTFs including bulk density and organic matter

Soil retention of hexavalent chromium released from construction and demolition waste in a road-base-application scenario

DEFF Research Database (Denmark)

Butera, Stefania; Trapp, Stefan; Astrup, Thomas Fruergaard

2015-01-01

We investigated the retention of Cr(VI) in three subsoils with low organic matter content in laboratory experiments at concentration levels relevant to represent leachates from construction and demolition waste (C&DW) reused as unbound material in road construction. The retention mechanism appeared...... depth. However, in rigid climates and with high water infiltration through the road pavement, the reduction reaction could be so slow that Cr(VI) might migrate as deep as 200 cm under the road. The reaction parameters and the model can form the basis for systematically assessing under which scenarios Cr...

Chemical evaluation of soil organic matter structure in diverse cropping systems

Science.gov (United States)

Soil organic matter (SOM) improves soil structure, nutrient and water retention, and biodiversity while reducing susceptibility to soil erosion. SOM also represents an important pool of C that can be increased to help mitigate global climate change. Our understanding of how agricultural management ...

Video Games Promote Saudi Children's English Vocabulary Retention

Science.gov (United States)

AlShaiji, Ohoud Abdullatif

2015-01-01

The objective of this study was to investigate the impact of Video Games and their role on promoting Saudi Kids' English vocabulary retention. The study attempted to answer whether there was a statistically significant difference (a = 0.05) between the Saudi children's subjects' mean score on the English vocabulary test due to using Video Games…

A Subject Matter Expert View of Curriculum Development.

Science.gov (United States)

Milazzo, M. P.; Anderson, R. B.; Edgar, L. A.; Gaither, T. A.; Vaughan, R. G.

2017-12-01

In 2015, NASA selected for funding the PLANETS project: Planetary Learning that Advances the Nexus of Engineering, Technology, and Science. The PLANETS partnership develops planetary science and engineering curricula for out of classroom time (OST) education settings. This partnership is between planetary science Subject Matter Experts (SMEs) at the US Geological Survey (USGS), curriculum developers at the Boston Museum of Science (MOS) Engineering is Everywhere (EiE), science and engineering teacher professional development experts at Northern Arizona University (NAU) Center for Science Teaching and Learning (CSTL), and OST teacher networks across the world. For the 2016 and 2017 Fiscal Years, our focus was on creating science material for two OST modules designed for middle school students. We have begun development of a third module for elementary school students. The first model teaches about the science and engineering of the availability of water in the Solar System, finding accessible water, evaluating it for quality, treating it for impurities, initial use, a cycle of greywater treatment and re-use, and final treatment of blackwater. This module is described in more detail in the abstract by L. Edgar et al., Water in the Solar System: The Development of Science Education Curriculum Focused on Planetary Exploration (233008) The second module involves the science and engineering of remote sensing in planetary exploration. This includes discussion and activities related to the electromagnetic spectrum, spectroscopy and various remote sensing systems and techniques. In these activities and discussions, we include observation and measurement techniques and tools as well as collection and use of specific data of interest to scientists. This module is described in more detail in the abstract by R. Anderson et al., Remote Sensing Mars Landing Sites: An Out-of-School Time Planetary Science Education Activity for Middle School Students (232683) The third module

Strategies to enhance participant recruitment and retention in research involving a community-based population.

Science.gov (United States)

McCullagh, Marjorie C; Sanon, Marie-Anne; Cohen, Michael A

2014-11-01

Challenges associated with recruiting and retaining community-based populations in research studies have been recognized yet remain of major concern for researchers. There is a need for exchange of recruitment and retention techniques that inform recruitment and retention strategies. Here, the authors discuss a variety of methods that were successful in exceeding target recruitment and retention goals in a randomized clinical trial of hearing protector use among farm operators. Recruitment and retention strategies were 1) based on a philosophy of mutually beneficial engagement in the research process, 2) culturally appropriate, 3) tailored to the unique needs of partnering agencies, and 4) developed and refined in a cyclical and iterative process. Sponsoring organizations are interested in cost-effective recruitment and retention strategies, particularly relating to culturally and ethnically diverse groups. These approaches may result in enhanced subject recruitment and retention, concomitant containment of study costs, and timely accomplishment of study aims. Copyright © 2014 Elsevier Inc. All rights reserved.

Multiple coding strategies in the retention of musical tones by possessors of absolute pitch.

Science.gov (United States)

Zatorre, R J; Beckett, C

1989-09-01

Eighteen musicians with absolute pitch (AP) confirmed by screening tests participated in tonal and verbal short-term-retention tasks. In the tonal task, subjects identified three successive piano tones by their letter names. Recall of these note names after 18 sec of counting backwards was near perfect. Recall after an 18-sec delay filled with random piano tones was also near perfect. In contrast, the same subjects demonstrated significant forgetting when required to retain letter trigrams while counting backwards for 18 sec. These results were essentially replicated in a second experiment using longer (27 sec) retention intervals, a more demanding verbal interference task, and an active musical interference task (singing a descending scale). We interpret these results as indicating that retention of note names by possessors of AP is not limited to verbal encoding; rather, multiple codes (e.g., auditory, kinesthetic, and visual imagery) are probably used.

The clearance concept with special reference to determination of glomerular filtration rate in patients with fluid retention

DEFF Research Database (Denmark)

Henriksen, Ulrik L; Henriksen, Jens H

2014-01-01

In subjects without fluid retention, the total plasma clearance of a renal filtration indicator (inulin, (99m) Tc-DTPA, (51) Cr-EDTA) is close to the urinary plasma clearance. Conversely, in patients with fluid retention (oedema, pleural effusions, ascites), there is a substantial discrepancy...

The Effects of Test Trial and Processing Level on Immediate and Delayed Retention

Science.gov (United States)

Chang, Sau Hou

2017-01-01

The purpose of the present study was to investigate the effects of test trial and processing level on immediate and delayed retention. A 2 × 2 × 2 mixed ANOVAs was used with two between-subject factors of test trial (single test, repeated test) and processing level (shallow, deep), and one within-subject factor of final recall (immediate, delayed). Seventy-six college students were randomly assigned first to the single test (studied the stimulus words three times and took one free-recall test) and the repeated test trials (studied the stimulus words once and took three consecutive free-recall tests), and then to the shallow processing level (asked whether each stimulus word was presented in capital letter or in small letter) and the deep processing level (whether each stimulus word belonged to a particular category) to study forty stimulus words. The immediate test was administered five minutes after the trials, whereas the delayed test was administered one week later. Results showed that single test trial recalled more words than repeated test trial in immediate final free-recall test, participants in deep processing performed better than those in shallow processing in both immediate and delayed retention. However, the dominance of single test trial and deep processing did not happen in delayed retention. Additional study trials did not further enhance the delayed retention of words encoded in deep processing, but did enhance the delayed retention of words encoded in shallow processing. PMID:28344679

The Effects of Test Trial and Processing Level on Immediate and Delayed Retention.

Science.gov (United States)

Chang, Sau Hou

2017-03-01

The purpose of the present study was to investigate the effects of test trial and processing level on immediate and delayed retention. A 2 × 2 × 2 mixed ANOVAs was used with two between-subject factors of test trial (single test, repeated test) and processing level (shallow, deep), and one within-subject factor of final recall (immediate, delayed). Seventy-six college students were randomly assigned first to the single test (studied the stimulus words three times and took one free-recall test) and the repeated test trials (studied the stimulus words once and took three consecutive free-recall tests), and then to the shallow processing level (asked whether each stimulus word was presented in capital letter or in small letter) and the deep processing level (whether each stimulus word belonged to a particular category) to study forty stimulus words. The immediate test was administered five minutes after the trials, whereas the delayed test was administered one week later. Results showed that single test trial recalled more words than repeated test trial in immediate final free-recall test, participants in deep processing performed better than those in shallow processing in both immediate and delayed retention. However, the dominance of single test trial and deep processing did not happen in delayed retention. Additional study trials did not further enhance the delayed retention of words encoded in deep processing, but did enhance the delayed retention of words encoded in shallow processing.

The Effects of Test Trial and Processing Level on Immediate and Delayed Retention

Directory of Open Access Journals (Sweden)

Sau Hou Chang

2017-03-01

Full Text Available The purpose of the present study was to investigate the effects of test trial and processing level on immediate and delayed retention. A 2 × 2 × 2 mixed ANOVAs was used with two between-subject factors of test trial (single test, repeated test and processing level (shallow, deep, and one within-subject factor of final recall (immediate, delayed. Seventy-six college students were randomly assigned first to the single test (studied the stimulus words three times and took one free-recall test and the repeated test trials (studied the stimulus words once and took three consecutive free-recall tests, and then to the shallow processing level (asked whether each stimulus word was presented in capital letter or in small letter and the deep processing level (whether each stimulus word belonged to a particular category to study forty stimulus words. The immediate test was administered five minutes after the trials, whereas the delayed test was administered one week later. Results showed that single test trial recalled more words than repeated test trial in immediate final free-recall test, participants in deep processing performed better than those in shallow processing in both immediate and delayed retention. However, the dominance of single test trial and deep processing did not happen in delayed retention. Additional study trials did not further enhance the delayed retention of words encoded in deep processing, but did enhance the delayed retention of words encoded in shallow processing.

Increased dopaminergic signaling impairs aversive olfactory memory retention in Drosophila.

Science.gov (United States)

Zhang, Shixing; Yin, Yan; Lu, Huimin; Guo, Aike

2008-05-23

Dopamine is necessary for the aversive olfactory associative memory formation in Drosophila, but its effect on other stages of memory is not known. Herein, we studied the effect of enhanced dopaminergic signaling on aversive olfactory memory retention in flies. We used l-3,4-dihydroxyphenylalanine (l-DOPA) to elevate dopamine levels: l-DOPA-treated flies exhibited a normal learning performance, but a decrease in 1-h memory. Dopamine transporter (DAT) mutant flies or flies treated with the DAT inhibitor desipramine exhibited poor memory retention. Flies subjected to heat stress after training exhibited a decrease in memory. Memory was restored by blocking dopaminergic neuronal output during heat stress, suggesting that dopamine is involved in heat stress-induced memory impairment in flies. Taken together, our findings suggest that increased dopaminergic signaling impairs aversive olfactory memory retention in flies.

Measurements of tritium retention and removal on TFTR

International Nuclear Information System (INIS)

Skinner, C.H.; Blanchard, W.; Kamperschroer, J.

1996-05-01

Recent experiments on the Tokamak Fusion Test Reactor (TFTR) have afforded an opportunity to measure the retention of tritium in a graphite limiter that is subject to erosion, codeposition and high neutron flux. The tritium was injected by both gas puff and neutral beams. The isotopic mix of hydrogenic recycling was measured spectroscopically and the tritium fraction T/(H+D+T) increased to as high as 75%. Some tritium was pumped out during the experimental run and some removed in a subsequent campaign using various clean-up techniques. While the short term retention of tritium was high, various conditioning techniques were successful in removing ∼ 8,000 Ci and restoring the tritium inventory to a level well below the administrative limit

Patient-centered recruitment and retention for a randomized controlled study.

Science.gov (United States)

Chhatre, Sumedha; Jefferson, Ashlie; Cook, Ratna; Meeker, Caitlin R; Kim, Ji Hyun; Hartz, Kayla Marie; Wong, Yu-Ning; Caruso, Adele; Newman, Diane K; Morales, Knashawn H; Jayadevappa, Ravishankar

2018-03-27

Recruitment and retention strategies for patient-centered outcomes research are evolving and research on the subject is limited. In this work, we present a conceptual model of patient-centered recruitment and retention, and describe the recruitment and retention activities and related challenges in a patient-centered comparative effectiveness trial. This is a multicenter, longitudinal randomized controlled trial in localized prostate cancer patients. We recruited 743 participants from three sites over 15 months period (January 2014 to March 2015), and followed them for 24 months. At site 1, of the 773 eligible participants, 551 (72%) were enrolled. At site 2, 34 participants were eligible and 23 (68%) enrolled. Of the 434 eligible participants at site 3, 169 (39%) enrolled. We observed that strategies related to the concepts of trust (e.g., physician involvement, ensuring protection of information), communication (e.g., brochures and pamphlets in physicians' offices, continued contact during regular clinic visits and calling/emailing assessment), attitude (e.g., emphasizing the altruistic value of research, positive attitude of providers and research staff), and expectations (e.g., full disclosure of study requirements and time commitment, update letters) facilitated successful patient recruitment and retention. A stakeholders' advisory board provided important input for the recruitment and retention activities. Active engagement, reminders at the offices, and personalized update letters helped retention during follow-up. Usefulness of telephone recruitment was site specific and, at one site, the time requirement for telephone recruitment was a challenge. We have presented multilevel strategies for successful recruitment and retention in a clinical trial using a patient-centered approach. Our strategies were flexible to accommodate site-level requirements. These strategies as well as the challenges can aid recruitment and retention efforts of future large

A dynamic processes study of PM retention by trees under different wind conditions.

Science.gov (United States)

Xie, Changkun; Kan, Liyan; Guo, Jiankang; Jin, Sijia; Li, Zhigang; Chen, Dan; Li, Xin; Che, Shengquan

2018-02-01

Particulate matter (PM) is one of the most serious environmental problems, exacerbating respiratory and vascular illnesses. Plants have the ability to reduce non-point source PM pollution through retention on leaves and branches. Studies of the dynamic processes of PM retention by plants and the mechanisms influencing this process will help to improve the efficiency of urban greening for PM reduction. We examined dynamic processes of PM retention and the major factors influencing PM retention by six trees with different branch structure characteristics in wind tunnel experiments at three different wind speeds. The results showed that the changes of PM numbers retained by plant leaves over time were complex dynamic processes for which maximum values could exceed minimum values by over 10 times. The average value of PM measured in multiple periods and situations can be considered a reliable indicator of the ability of the plant to retain PM. The dynamic processes were similar for PM 10 and PM 2.5 . They could be clustered into three groups simulated by continually-rising, inverse U-shaped, and U-shaped polynomial functions, respectively. The processes were the synthetic effect of characteristics such as species, wind speed, period of exposure and their interactions. Continually-rising functions always explained PM retention in species with extremely complex branch structure. Inverse U-shaped processes explained PM retention in species with relatively simple branch structure and gentle wind. The U-shaped processes mainly explained PM retention at high wind speeds and in species with a relatively simple crown. These results indicate that using plants with complex crowns in urban greening and decreasing wind speed in plant communities increases the chance of continually-rising or inverse U-shaped relationships, which have a positive effect in reducing PM pollution. Copyright © 2017 Elsevier Ltd. All rights reserved.

Urinary retention and post-void residual urine in men: separating truth from tradition.

Science.gov (United States)

Kaplan, Steven A; Wein, Alan J; Staskin, David R; Roehrborn, Claus G; Steers, William D

2008-07-01

The definitions of acute and chronic urinary retention remain empirical and subject to wide interpretation. Standardized criteria have not been established and many questions remain unanswered. Moreover, the definition of significant post-void residual urine is unclear. We reviewed several aspects of urinary retention that require clarification with the objective of stimulating discussion among urologists to establish an accurate and coherent definition of urinary retention and significant post-void residual urine, and clarify risk factors. A MEDLINE search for articles written in English and published before April 2007 was done using a list of terms related to urinary retention. Articles not directly relevant to urinary retention or post-void residual urine were excluded. The term urinary retention lacks precise clinical or urodynamic meaning. Use of this term to describe a symptom, a sign, and a condition further complicates the issue. Many factors can contribute to the development of retention, including bladder outlet obstruction, detrusor underactivity, and neurogenic bladder conditions. Community based studies and clinical trials in patients with benign prostatic enlargement and/or lower urinary tract symptoms yield different estimates of the incidence of retention and only provide information on the epidemiology of acute urinary retention. However, age, previous retention episodes, lower urinary tract symptoms, chronic inflammation, serum prostate specific antigen level, prostate size, and urodynamic variables appear to be predictors of acute urinary retention. Alpha-receptor antagonists and 5alpha-reductase inhibitors may be useful in preventing urinary retention episodes and progressive benign prostatic enlargement. Clinical trials on the short-term use of antimuscarinics have not provided evidence that these agents increase the risk of retention; data on longer term administration are needed. Clinicians are adopting less invasive approaches (eg

Non-labile Soil Nitrogen Retention beneath Three Tree Species in a Tropical Plantation

Science.gov (United States)

Jason P. Kaye; Dan Binkley; Xiaoming Zou

2002-01-01

Soil organic matter is the largest sink for N additions to forests. Species composition may affect soilNretention by altering the amount or proportion of added N stored in non-labile organic pools. We measured 15N tracer retention in labile and non-labile pools of surface (0–20 cm) mineral soils, 7 yr after the tracer was applied to a 9 yr-old Puerto Rican tree...

Retention and leaching of nitrite by municipal solid waste incinerator bottom ash under the landfill circumstance.

Science.gov (United States)

Yao, Jun; Kong, Qingna; Zhu, Huayue; Long, Yuyang; Shen, Dongsheng

2015-01-01

The retention and leaching of nitrite by municipal solid waste incinerator (MSWI) bottom ash could affect its migration in the landfill. In this study, the effect of the dosage of MSWI bottom ash as well as the variation of the landfill environmental parameters including pH, anions and organic matter on the nitrite retention and leaching behavior was investigated by batch experiments. The highest removal percentage (73.0%) of nitrite was observed when the dosage of MSWI bottom ash was 10 g L(-1) in 2 mg L(-1) nitrite solution. Further increase of the dosage would retard the retention, as the nitrite leaching from MSWI bottom ash was enhanced. The optimum retention of nitrite was observed when the pH was 5.0, while the leaching of nitrite showed a consistent reduction with the increase of pH. Besides, the presence of Cl(-), SO4(2)(-) and acetic acid could enhance the leaching of nitrite and mitigate the retention process. However, the retention of nitrite was enhanced by PO4(3)(-), which was probably due to the formation of the apatite, an active material for the adsorption of the nitrite. These results suggested that MSWI bottom ash could affect the migration of nitrite in the landfill, which was related to the variation of the landfill circumstance. Copyright © 2014 Elsevier Ltd. All rights reserved.

Water retention and runoff formation in the Krkonoše Mts

Czech Academy of Sciences Publication Activity Database

Šír, Miloslav; Tesař, Miroslav

2013-01-01

Roč. 50, August (2013), s. 97-106 ISSN 0139-925X R&D Projects: GA TA ČR TA02021451 Institutional support: RVO:67985874 Keywords : mountain hydrology * runoff formation * catchment water retention * soil water movement Subject RIV: DA - Hydrology ; Limnology

Does Variation in the Extent of Generalized Trust, Individual Education and Extensiveness of Social Security Policies Matter for Maximization of Subjective Well-Being?

Science.gov (United States)

Valeeva, Rania F.

2016-01-01

In this paper, I examine whether generalized trust and education, as well as social security policies of welfare state institutions matter for cross-national differences in subjective well-being (SWB), because knowledge on this issue is still lacking. For this purpose I integrated the insights of two sociological theories: Social Function…

Emotional intelligence and clinical performance/retention of nursing students

Science.gov (United States)

Marvos, Chelsea; Hale, Frankie B.

2015-01-01

Objective: This exploratory, quantitative, descriptive study was undertaken to explore the relationship between clinical performance and anticipated retention in nursing students. Methods: After approval by the university's Human Subjects Committee, a sample of 104 nursing students were recruited for this study, which involved testing with a valid and reliable emotional intelligence (EI) instrument and a self-report survey of clinical competencies. Results: Statistical analysis revealed that although the group average for total EI score and the 6 score subsets were in the average range, approximately 30% of the individual total EI scores and 30% of two branch scores, identifying emotions correctly and understanding emotions, fell in the less than average range. This data, as well as the analysis of correlation with clinical self-report scores, suggest recommendations applicable to educators of clinical nursing students. Conclusions: Registered nurses make-up the largest segment of the ever-growing healthcare workforce. Yet, retention of new graduates has historically been a challenge for the profession. Given the projected employment growth in nursing, it is important to identify factors which correlate with high levels of performance and job retention among nurses. There is preliminary evidence that EI a nontraditional intelligence measure relates positively not only with retention of clinical staff nurses, but with overall clinical performance as well. PMID:27981096

Subject (of documents)

DEFF Research Database (Denmark)

Hjørland, Birger

2017-01-01

This article presents and discuss the concept “subject” or subject matter (of documents) as it has been examined in library and information science (LIS) for more than 100 years. Different theoretical positions are outlined and it is found that the most important distinction is between document......-oriented views versus request-oriented views. The document-oriented view conceive subject as something inherent in documents, whereas the request-oriented view (or the policy based view) understand subject as an attribution made to documents in order to facilitate certain uses of them. Related concepts...

Gray matter alterations and correlation of nutritional intake with the gray matter volume in prediabetes

Science.gov (United States)

Hou, Yi-Cheng; Lai, Chien-Han; Wu, Yu-Te; Yang, Shwu-Huey

2016-01-01

Abstract The neurophysiology of prediabetes plays an important role in preventive medicine. The dysregulation of glucose metabolism is likely linked to changes in neuron-related gray matter. Therefore, we designed this study to investigate gray matter alterations in medication-naive prediabetic patients. We expected to find alterations in the gray matter of prediabetic patients. A total of 64 prediabetic patients and 54 controls were enrolled. All subjects received T1 scans using a 3-T magnetic resonance imaging machine. Subjects also completed nutritional intake records at the 24-hour and 3-day time points to determine their carbohydrate, protein, fat, and total calorie intake. We utilized optimized voxel-based morphometry to estimate the gray matter differences between the patients and controls. In addition, the preprandial serum glucose level and the carbohydrate, protein, fat, and total calorie intake levels were tested to determine whether these parameters were correlated with the gray matter volume. Prediabetic patients had lower gray matter volumes than controls in the right anterior cingulate gyrus, right posterior cingulate gyrus, left insula, left super temporal gyrus, and left middle temporal gyrus (corrected P prediabetic patients. PMID:27336893

The Effects of Test Trial and Processing Level on Immediate and Delayed Retention

Science.gov (United States)

Chang, Sau Hou

2017-01-01

The purpose of the present study was to investigate the effects of test trial and processing level on immediate and delayed retention. A 2 × 2 × 2 mixed ANOVAs was used with two between-subject factors of test trial (single test, repeated test) and processing level (shallow, deep), and one within-subject factor of final recall (immediate,…

Evaluating the utility of subjective effects measures for predicting product sampling, enrollment, and retention in a clinical trial of a smokeless tobacco product.

Science.gov (United States)

O'Connor, Richard J; Lindgren, Bruce R; Schneller, Liane M; Shields, Peter G; Hatsukami, Dorothy K

2018-01-01

Subjective effects of drugs, representing pharmacological and non-pharmacological effects, have been shown to be associated with future use and abuse. This also is the case for tobacco products and so measuring subjective effects, such as liking, satisfaction, and aversion, is crucial to gaining an understanding of consumer perception leading to increased use. This study examined the predictive validity of subjective drug and product effects with respect to product adoption. Smokers (N=151) were enrolled in Minneapolis, Columbus, and Buffalo. Participants were shown two snus products (Camel Snus Winterchill and Robust), asked to try each of the products for 5min and to rate them using the Product Evaluation Scale (PES) and Drug Effects Questionnaire (DEQ). This was followed by a one-week use period of their preferred product and those who used at least 1 unit of Camel Snus per day (or at least 7 pouches total) were eligible to enroll in the Clinical Trial Phase assessing the impact of complete switching or dual use with smoking. Key outcomes for this study were product evaluation, extent of product use, and Clinical Trial enrollment. We noted no relationships between participant characteristics such as gender, age, prior smokeless use, baseline cigarettes per day (CPD), or PES and DEQ scores with any of these outcome variables. Subjective effects were weak predictors of product use, which totaled approximately 3units of snus per day. Regardless of product, it appears that PES and DEQ ratings were uniformly poor predictors of trial enrollment and retention, though they do predict the amount of snus used during the sampling phase. Findings indicate that while subjective effects predict product preference in the short-term, they did not consistently predict extent of use or enrollment in the trial, suggesting that these initial measures have limited implications for long-term behavior. Copyright © 2017. Published by Elsevier Ltd.

The effect of productive classroom talk and metacommunication on young children's oral communicative competence and subject matter knowledge: An intervention study in early childhood education

NARCIS (Netherlands)

van der Veen, C.; de Mey, J.R.P.B.; van Kruistum, C.J.; van Oers, B.

The aim of the present study was to investigate the effect of productive classroom talk and metacommunication on the development of young children's oral communicative competence and subject matter knowledge. This study can be characterized as a quasi-experimental study with a

Enhancement of water retention by cross-linked carboxymethylcellulose through polystyrene grafting or γ irradiation

International Nuclear Information System (INIS)

Bhattacharjee, S.S.; Perlin, A.S.

1975-01-01

The absorbency and retention characteristics of crosslinked carboxymethylcellulose (CLCMC) with respect to water and saline can be substantially improved by two different treatments. One treatment involves γ-radioinduced grafting of polystyrene onto fibers of CLCMC. At a critical level of grafting (approximately 25 percent) the retentive capacity of the fibers is almost doubled. Particularly noteworthy is the sharp increase that follows an initial drop in retentivity. It is concluded the polystyrene becomes associated preferentially with residual ordered regions of the CLCMC macromolecule, through the localization of free radicals in these regions. A second means for enhancing the water and saline retention value of CLCMC, consists of subjecting the material to gamma irradiation from a 60 Co source. Dosages used have ranged from 1.0 to 4.8 megarads (MR), depending on the degree of substitution of the initial carboxymethylcellulose. (JGB)

Immediate and Long-Term Retention For Pictorial and Verbal Stimuli.

Science.gov (United States)

Purdy, Jesse E.; Luepnitz, Roy R.

1982-01-01

Sixty-four subjects were presented pictures and later asked to draw them or provide one-word descriptions to test the hypothesis that decreased retention effectiveness occurs because images stored in long-term memory are accessible only through their verbal labels. Recall of pictures was significantly greater than recall of words. (Author/PN)

Water retention of repellent and subcritical repellent soils: New insights from model and experimental investigations

Science.gov (United States)

Czachor, H.; Doerr, S. H.; Lichner, L.

2010-01-01

SummarySoil organic matter can modify the surface properties of the soil mineral phase by changing the surface tension of the mineral surfaces. This modifies the soil's solid-water contact angle, which in turn would be expected to affect its water retention curve (SWRC). Here we model the impact of differences in the soil pore-water contact angle on capillarity in non-cylindrical pores by accounting for their complex pore geometry. Key outcomes from the model include that (i) available methods for measuring the Young's wetting angle on soil samples are insufficient in representing the wetting angle in the soil pore space, (ii) the wetting branch of water retention curves is strongly affected by the soil pore-water contact angle, as manifest in the wetting behavior of water repellent soils, (iii) effects for the drying branch are minimal, indicating that both wettable and water repellent soils should behave similarly, and (vi) water retention is a feature not of only wettable soils, but also soils that are in a water repellent state. These results are tested experimentally by determining drying and wetting branches for (a) 'model soil' (quartz sands with four hydrophobization levels) and (b) five field soil samples with contrasting wettability, which were used with and without the removal of the soil organic matter. The experimental results support the theoretical predictions and indicate that small changes in wetting angle can cause switches between wettable and water repellent soil behavior. This may explain the common observation that relatively small changes in soil water content can cause substantial changes in soil wettability.

Predictors of Atrasentan-Associated Fluid Retention and Change in Albuminuria in Patients with Diabetic Nephropathy

DEFF Research Database (Denmark)

Kohan, Donald E; Lambers Heerspink, Hiddo J; Coll, Blai

2015-01-01

. CONCLUSIONS: In the Reducing Residual Albuminuria in Subjects With Diabetes and Nephropathy With Atrasentan/JAPAN trials, atrasentan-associated fluid retention was more likely in patients with diabetes and nephropathy who had lower eGFR or received a higher dose of atrasentan. Finding that albuminuria......BACKGROUND AND OBJECTIVES: Endothelin A receptor antagonists (ERAs) decrease residual albuminuria in patients with diabetic kidney disease; however, their clinical utility may be limited by fluid retention. Consequently, the primary objective of this study was to identify predictors for ERA......-induced fluid retention among patients with type 2 diabetes and CKD. A secondary objective was to determine if the degree of fluid retention necessarily correlated with the magnitude of albuminuria reduction in those patients receiving ERAs. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: A post hoc analysis...

Cross-Cultural Adjustment of Native-Speaking English Teachers (NETs) in Hong Kong: A Factor in Attrition and Retention

Science.gov (United States)

Chu, Chau Kan; Morrison, Keith

2011-01-01

This paper argues that, despite government support in financial and contractual matters, ongoing problems of retention of Native-speaking English Teachers (NETs) in Hong Kong stem, in part, from problems of cross-cultural adjustment. The paper reports a small-scale qualitative investigation into the experiences of NETS in Hong Kong and finds…

Urinary retention in women.

Science.gov (United States)

Juma, Saad

2014-07-01

This review is a summary of the most pertinent published studies in the literature in the last 18 months that address cause, diagnosis, and management of urinary retention in women. Symptoms, uroflow, and pressure-flow studies have a low predictive value for and do not correlate with elevated postvoid residual urine (PVR). Anterior and posterior colporrhaphy do not cause de-novo bladder outlet obstruction in the majority of patients with elevated PVR, and the cause of elevated PVR may be other factors such as pain or anxiety causing abnormal relaxation of the pelvic floor and contributing to voiding difficulty. The risk of urinary retention in a future pregnancy after mid-urethral sling (MUS) is small. The risk of urinary tract infection and urinary retention after chemodenervation of the bladder with onabotulinumtoxin-A (100 IU) in patients with non-neurogenic urge incontinence is 33 and 5%, respectively. There is a lack of consensus among experts on the timing of sling takedown in the management of acute urinary retention following MUS procedures. There has been a significant progress in the understanding of the causation of urinary retention. Important areas that need further research (basic and clinical) are post-MUS and pelvic organ prolapse repair urinary retention and obstruction, and urinary retention owing to detrusor underactivity.

Emotional intelligence and clinical performance/retention of nursing students

Directory of Open Access Journals (Sweden)

Chelsea Marvos

2015-01-01

Full Text Available Objective: This exploratory, quantitative, descriptive study was undertaken to explore the relationship between clinical performance and anticipated retention in nursing students. Methods: After approval by the university′s Human Subjects Committee, a sample of 104 nursing students were recruited for this study, which involved testing with a valid and reliable emotional intelligence (EI instrument and a self-report survey of clinical competencies. Results: Statistical analysis revealed that although the group average for total EI score and the 6 score subsets were in the average range, approximately 30% of the individual total EI scores and 30% of two branch scores, identifying emotions correctly and understanding emotions, fell in the less than average range. This data, as well as the analysis of correlation with clinical self-report scores, suggest recommendations applicable to educators of clinical nursing students. Conclusions: Registered nurses make-up the largest segment of the ever-growing healthcare workforce. Yet, retention of new graduates has historically been a challenge for the profession. Given the projected employment growth in nursing, it is important to identify factors which correlate with high levels of performance and job retention among nurses. There is preliminary evidence that EI "a nontraditional intelligence measure" relates positively not only with retention of clinical staff nurses, but with overall clinical performance as well.

Relative activity of cerebral subcortical gray matter in varying states of attention and awareness in normal subjects and patient studies

International Nuclear Information System (INIS)

Cooper, M.; Chen, C.T.; Levy, J.; Wagner, N.; Spire, J.P.; Jacobsen, J.; Meltzer, H.; Metz, J.; Beck, R.N.

1985-01-01

An important aspect of the study of brain function involves measurement of the relationships; between activities in the subcortical gray matter of the caudate and of the thalamus; and between these structures and functional cortical areas. The authors have studied these relationships in 22 subjects under different conditions of activation, sleep and sensory deprivation using a PET VI system and F-18-2DG to determine regional cerebral metabolism. Subject activating conditions were maintained throughout the period of equilibration of F-18-2DG and E.E.G.'s were monitored. Multiple tomographic slices of 1-2 million counts were obtained simultaneously with slice separation of 14mm and each plane parallel to the cantho-meatal line. In activated and non-activated awake conditions for normal subjects, left and right thalmus-to-caudate ratios were similar and greater than unity. This relationship was maintained in non-REM sleep, but was reversed and divergent in REM sleep and sensory deprivation; this was also evident in 3/4 narcoleptics awake and asleep in non-REM and REM and 2/3 schizophrenics and affective disorder, subjects. This approach appears to have potential for characterizating normal and disordered regional cerebral function

Fission product retention in TRISO coated UO2 particle fuels subjected to HTR simulated core heating tests

International Nuclear Information System (INIS)

Baldwin, C.A.; Kania, M.J.

1991-01-01

Results of the examination and analysis of 25,730 individual microspheres from spherical fuel elements HFR-K3/1 and HFR-K3/3 are reported. The parent spheres were irradiated in excess of end-of-life exposure and subsequently subjected to simulated core heating tests in a special high-temperature furnace at Forschungszentrum, Juelich, GmbH (KFA). Following the heating tests, the spheres were electrolytically deconsolidated to obtain unbounded fuel particles for Irradiated Microsphere Gamma Analyzer (IMGA) analysis. For sphere HFR-K3/1, which was heated for 500 h at 1600 deg. C, only four particles were identified as having released fission products. The remaining particles from the sphere showed no statistical evidence of fission product release. Scanning Electron Microscopy (SEM) examination showed that three of the defect particles had large sections of the TRISO coating missing, while the fourth appeared normal. For sphere HFR-K3/3, which was heated for 100 h at 1800 deg. C, the IMGA data revealed that fission product release (cesium) from individual particles was significant and that there was large particle-to-particle variation in retention capabilities. Individual particle release (cesium) averaged ten times the KFA-measured integral spherical fuel element release value. In addition, the bimodal distribution of the individual particle data indicated that two distinct modes of failure at fuel temperatures of 1800 deg. C and above may exist. (author). 6 refs, 6 figs, 4 tabs

Fission product retention in TRISCO coated UO2 particle fuels subjected to HTR simulated core heating tests

International Nuclear Information System (INIS)

Baldwin, C.A.; Kania, M.J.

1990-11-01

Results of the examination and analysis of 25,730 individual microspheres from spherical fuel elements HFR-K3/1 and HFR-K3/3 are reported. The parent spheres were irradiated in excess of end-of-life exposure and subsequently subjected to simulated core heating tests in a special high-temperature furnace at Forschungszentrum, Juelich, GmbH (KFA). Following the heating tests, the spheres were electrolytically deconsolidated to obtain unbonded fuel particles for Irradiated Microsphere Gamma Analyzer (IMGA) analysis. For sphere HFR-K3/1, which was heated for 500 h at 1600 degree C, only four particles were identified as having released fission products. The remaining particles from the sphere showed no statistical evidence of fission product release. Scanning Electron Microscopy (SEM) examination showed that three of the defect particles had large sections of the TRISO coating missing, while the fourth appeared normal. For sphere HFR-K3/3, which was heated for 100 h at 1800 degree C, the IMGA data revealed that fission product release (cesium) from individual particles was significant and that there was large particle-to-particle variation in retention capabilities. Individual particle release (cesium) averaged ten times the KFA-measured integral spherical fuel element release value. In addition, the bimodal distribution of the individual particle data indicated that two distinct modes of failure at fuel temperatures of 1800 degree C and above may exist. 6 refs., 6 figs., 4 tabs

White matter integrity in kleptomania: A pilot study

Science.gov (United States)

Grant, Jon E.; Correia, Stephen; Brennan-Krohn, Thea

2007-01-01

This study's goal was to examine microstructural organization of frontal white matter in kleptomania. Ten females with DSM-IV kleptomania and 10 female controls underwent diffusion tensor imaging. Inferior frontal white matter was the a priori region of interest. Trace and fractional anisotropy (FA) were also calculated for frontal and posterior cortical regions in both subject groups. Kleptomania subjects had significantly higher mean frontal Trace, and significantly lower mean frontal FA than control subjects. Group differences remained significant when right and left frontal Trace and FA were analyzed. Groups did not differ significantly in posterior Trace or FA. Kleptomania may be associated with decreased white matter microstructural integrity in inferior frontal brain regions. PMID:16956753

Major Superficial White Matter Abnormalities in Huntington's Disease

Science.gov (United States)

Phillips, Owen R.; Joshi, Shantanu H.; Squitieri, Ferdinando; Sanchez-Castaneda, Cristina; Narr, Katherine; Shattuck, David W.; Caltagirone, Carlo; Sabatini, Umberto; Di Paola, Margherita

2016-01-01

Background: The late myelinating superficial white matter at the juncture of the cortical gray and white matter comprising the intracortical myelin and short-range association fibers has not received attention in Huntington's disease. It is an area of the brain that is late myelinating and is sensitive to both normal aging and neurodegenerative disease effects. Therefore, it may be sensitive to Huntington's disease processes. Methods: Structural MRI data from 25 Pre-symptomatic subjects, 24 Huntington's disease patients and 49 healthy controls was run through a cortical pattern-matching program. The surface corresponding to the white matter directly below the cortical gray matter was then extracted. Individual subject's Diffusion Tensor Imaging (DTI) data was aligned to their structural MRI data. Diffusivity values along the white matter surface were then sampled at each vertex point. DTI measures with high spatial resolution across the superficial white matter surface were then analyzed with the General Linear Model to test for the effects of disease. Results: There was an overall increase in the axial and radial diffusivity across much of the superficial white matter (p < 0.001) in Pre-symptomatic subjects compared to controls. In Huntington's disease patients increased diffusivity covered essentially the whole brain (p < 0.001). Changes are correlated with genotype (CAG repeat number) and disease burden (p < 0.001). Conclusions: This study showed broad abnormalities in superficial white matter even before symptoms are present in Huntington's disease. Since, the superficial white matter has a unique microstructure and function these abnormalities suggest it plays an important role in the disease. PMID:27242403

The Place of Subject Matter Knowledge in Pedagogical Content Knowledge: A Case Study of South African Teachers Teaching the Amount of Substance and Chemical Equilibrium

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Rollnick, Marissa; Bennett, Judith; Rhemtula, Mariam; Dharsey, Nadine; Ndlovu, Thandi

2008-01-01

This paper presents two South African case studies designed to explore the influence of subject matter knowledge on pedagogical content knowledge (PCK). In the first case study on teaching the mole in two township schools, the findings illustrate that the participant teachers favoured procedural approaches at the expense of conceptual…

Retention interval affects visual short-term memory encoding.

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Bankó, Eva M; Vidnyánszky, Zoltán

2010-03-01

Humans can efficiently store fine-detailed facial emotional information in visual short-term memory for several seconds. However, an unresolved question is whether the same neural mechanisms underlie high-fidelity short-term memory for emotional expressions at different retention intervals. Here we show that retention interval affects the neural processes of short-term memory encoding using a delayed facial emotion discrimination task. The early sensory P100 component of the event-related potentials (ERP) was larger in the 1-s interstimulus interval (ISI) condition than in the 6-s ISI condition, whereas the face-specific N170 component was larger in the longer ISI condition. Furthermore, the memory-related late P3b component of the ERP responses was also modulated by retention interval: it was reduced in the 1-s ISI as compared with the 6-s condition. The present findings cannot be explained based on differences in sensory processing demands or overall task difficulty because there was no difference in the stimulus information and subjects' performance between the two different ISI conditions. These results reveal that encoding processes underlying high-precision short-term memory for facial emotional expressions are modulated depending on whether information has to be stored for one or for several seconds.

Gray matter alterations and correlation of nutritional intake with the gray matter volume in prediabetes

OpenAIRE

Hou, Yi-Cheng; Lai, Chien-Han; Wu, Yu-Te; Yang, Shwu-Huey

2016-01-01

Abstract The neurophysiology of prediabetes plays an important role in preventive medicine. The dysregulation of glucose metabolism is likely linked to changes in neuron-related gray matter. Therefore, we designed this study to investigate gray matter alterations in medication-naive prediabetic patients. We expected to find alterations in the gray matter of prediabetic patients. A total of 64 prediabetic patients and 54 controls were enrolled. All subjects received T1 scans using a 3-T magnet...

Simplified tools for measuring retention in care in antiretroviral treatment program in Ethiopia: cohort and current retention in care.

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Assefa, Yibeltal; Worku, Alemayehu; Wouters, Edwin; Koole, Olivier; Haile Mariam, Damen; Van Damme, Wim

2012-01-01

Patient retention in care is a critical challenge for antiretroviral treatment programs. This is mainly because retention in care is related to adherence to treatment and patient survival. It is therefore imperative that health facilities and programs measure patient retention in care. However, the currently available tools, such as Kaplan Meier, for measuring retention in care have a lot of practical limitations. The objective of this study was to develop simplified tools for measuring retention in care. Retrospective cohort data were collected from patient registers in nine health facilities in Ethiopia. Retention in care was the primary outcome for the study. Tools were developed to measure "current retention" in care during a specific period of time for a specific "ART-age group" and "cohort retention" in care among patients who were followed for the last "Y" number of years on ART. "Probability of retention" based on the tool for "cohort retention" in care was compared with "probability of retention" based on Kaplan Meier. We found that the new tools enable to measure "current retention" and "cohort retention" in care. We also found that the tools were easy to use and did not require advanced statistical skills. Both "current retention" and "cohort retention" are lower among patients in the first two "ART-age groups" and "ART-age cohorts" than in subsequent "ART-age groups" and "ART-age cohorts". The "probability of retention" based on the new tools were found to be similar to the "probability of retention" based on Kaplan Meier. The simplified tools for "current retention" and "cohort retention" will enable practitioners and program managers to measure and monitor rates of retention in care easily and appropriately. We therefore recommend that health facilities and programs start to use these tools in their efforts to improve retention in care and patient outcomes.

Simplified tools for measuring retention in care in antiretroviral treatment program in Ethiopia: cohort and current retention in care.

Directory of Open Access Journals (Sweden)

Yibeltal Assefa

Full Text Available INTRODUCTION: Patient retention in care is a critical challenge for antiretroviral treatment programs. This is mainly because retention in care is related to adherence to treatment and patient survival. It is therefore imperative that health facilities and programs measure patient retention in care. However, the currently available tools, such as Kaplan Meier, for measuring retention in care have a lot of practical limitations. The objective of this study was to develop simplified tools for measuring retention in care. METHODS: Retrospective cohort data were collected from patient registers in nine health facilities in Ethiopia. Retention in care was the primary outcome for the study. Tools were developed to measure "current retention" in care during a specific period of time for a specific "ART-age group" and "cohort retention" in care among patients who were followed for the last "Y" number of years on ART. "Probability of retention" based on the tool for "cohort retention" in care was compared with "probability of retention" based on Kaplan Meier. RESULTS: We found that the new tools enable to measure "current retention" and "cohort retention" in care. We also found that the tools were easy to use and did not require advanced statistical skills. Both "current retention" and "cohort retention" are lower among patients in the first two "ART-age groups" and "ART-age cohorts" than in subsequent "ART-age groups" and "ART-age cohorts". The "probability of retention" based on the new tools were found to be similar to the "probability of retention" based on Kaplan Meier. CONCLUSION: The simplified tools for "current retention" and "cohort retention" will enable practitioners and program managers to measure and monitor rates of retention in care easily and appropriately. We therefore recommend that health facilities and programs start to use these tools in their efforts to improve retention in care and patient outcomes.

Retention in methadone maintenance treatment in mainland China, 2004-2012: a literature review.

Science.gov (United States)

Zhou, Kaina; Zhuang, Guihua

2014-01-01

Methadone maintenance treatment (MMT) was implemented in mainland China since 2004. Numerous individual studies have investigated MMT retention but the overview still remains unclear. The aim of the study was to review MMT retention rates and predicting factors in mainland China during 2004-2012. Chinese and English databases of literature were searched for studies reporting on retention rates and predicting factors in non-transfer MMT patients of fixed-site clinics in mainland China (2004-2012). Qualitative methods were used to synthesize the results. Nineteen studies were eligible for review, with sample size ranging from 29 to 3758. Retention rates varied between 30.0% at 6 months in Shanghai and 70.3% at 12 months in Xi'an. Predicting factors were non-treatment including sociodemographics (n=14), support system and social function (n=9), economic status (n=2) and psychological status (n=1), and treatment-related including drug use (n=15), methadone use (n=12), MMT clinics (n=9), MMT participation (n=7), awareness on MMT (n=5) and HIV serostatus (n=3). Methadone dose (n=12) and age (n=7) were the first two important specific factors. In mainland China, MMT retention rates are heterogeneous and relatively lower, and predicting factors mainly focus on objective aspects. Future work should further explore subjective predicting factors regarding MMT retention. © 2013.

Retention period after treatment of posterior crossbite with maxillary expansion: a systematic review

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Julia Garcia Costa

Full Text Available ABSTRACT OBJECTIVE: The aim of this systematic review was to evaluate the duration of the retention period in growing patients undergoing maxillary expansion and its relation with posterior crossbite stability. METHODS: Search strategies were executed for electronic databases Cochrane Library, Web of Science, PubMed and Scopus, which were completed on January 15, 2016. The inclusion criteria included randomized, prospective or retrospective controlled trials in growing subjects with posterior crossbite; treated with maxillary expanders; retention phase after expansion; post-retention phase of at least 6 months. The exclusion criteria were anterior crossbite, craniofacial anomalies, surgery or another orthodontic intervention; case reports; author’s opinions articles, thesis, literature reviews and systematic reviews. The risk of bias of selected articles was assessed with Cochrane risk of bias tool for RCTs and Downs and Black checklist for non-RCTs. RESULTS: A total of 156 titles/abstracts was retrieved, 44 full-texts were examined, and 6 articles were selected and assessed for their methodological quality. The retention period after maxillary expansion ranged between 4 weeks and 16 months. Fixed (acrylic plate, Haas, Hyrax and quad-helix or removable (Hawley and Hawley expander appliances were used for retention. CONCLUSIONS: Six months of retention with either fixed or removable appliances seem to be enough to avoid relapse or to guarantee minimal changes in a short-term follow-up.

Effects of Visual Feedback Distortion on Gait Adaptation: Comparison of Implicit Visual Distortion Versus Conscious Modulation on Retention of Motor Learning.

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Kim, Seung-Jae; Ogilvie, Mitchell; Shimabukuro, Nathan; Stewart, Trevor; Shin, Joon-Ho

2015-09-01

Visual feedback can be used during gait rehabilitation to improve the efficacy of training. We presented a paradigm called visual feedback distortion; the visual representation of step length was manipulated during treadmill walking. Our prior work demonstrated that an implicit distortion of visual feedback of step length entails an unintentional adaptive process in the subjects' spatial gait pattern. Here, we investigated whether the implicit visual feedback distortion, versus conscious correction, promotes efficient locomotor adaptation that relates to greater retention of a task. Thirteen healthy subjects were studied under two conditions: (1) we implicitly distorted the visual representation of their gait symmetry over 14 min, and (2) with help of visual feedback, subjects were told to walk on the treadmill with the intent of attaining the gait asymmetry observed during the first implicit trial. After adaptation, the visual feedback was removed while subjects continued walking normally. Over this 6-min period, retention of preserved asymmetric pattern was assessed. We found that there was a greater retention rate during the implicit distortion trial than that of the visually guided conscious modulation trial. This study highlights the important role of implicit learning in the context of gait rehabilitation by demonstrating that training with implicit visual feedback distortion may produce longer lasting effects. This suggests that using visual feedback distortion could improve the effectiveness of treadmill rehabilitation processes by influencing the retention of motor skills.

Seed Implant Retention Score Predicts the Risk of Prolonged Urinary Retention After Prostate Brachytherapy

International Nuclear Information System (INIS)

Lee, Hoon K.; Adams, Marc T.; Shi, Qiuhu; Basillote, Jay; LaMonica, Joanne; Miranda, Luis; Motta, Joseph

2010-01-01

Purpose: To risk-stratify patients for urinary retention after prostate brachytherapy according to a novel seed implant retention score (SIRS). Patients and Methods: A total of 835 patients underwent transperineal prostate seed implant from March 1993 to January 2007; 197 patients had 125 I and 638 patients had 103 Pd brachytherapy. Four hundred ninety-four patients had supplemental external-beam radiation. The final downsized prostate volume was used for the 424 patients who had neoadjuvant hormone therapy. Retention was defined as reinsertion of a Foley catheter after the implant. Results: Retention developed in 7.4% of patients, with an average duration of 6.7 weeks. On univariate analysis, implant without supplemental external-beam radiation (10% vs. 5.6%; p = 0.02), neoadjuvant hormone therapy (9.4% vs. 5.4%; p = 0.02), baseline α-blocker use (12.5% vs. 6.3%; p = 0.008), and increased prostate volume (13.4% vs. 6.9% vs. 2.9%, >45 cm 3 , 25-45 cm 3 , 3 ; p = 0.0008) were significantly correlated with increased rates of retention. On multivariate analysis, implant without supplemental external-beam radiation, neoadjuvant hormone therapy, baseline α-blocker use, and increased prostate volume were correlated with retention. A novel SIRS was modeled as the combined score of these factors, ranging from 0 to 5. There was a significant correlation between the SIRS and retention (p < 0.0001). The rates of retention were 0, 4%, 5.6%, 9%, 20.9%, and 36.4% for SIRS of 0 to 5, respectively. Conclusions: The SIRS may identify patients who are at high risk for prolonged retention after prostate brachytherapy. A prospective validation study of the SIRS is planned.

Using the theory of reasoned action to model retention in rural primary care physicians.

Science.gov (United States)

Feeley, Thomas Hugh

2003-01-01

Much research attention has focused on medical students', residents', and physicians' decisions to join a rural practice, but far fewer studies have examined retention of rural primary care physicians. The current review uses Fishbein and Ajzen's Theory of Reasoned Action (TRA) to organize the literature on the predictors and correlates of retention of rural practicing physicians. TRA suggests turnover behavior is directly predicted by one's turnover intentions, which are, in turn, predicted by one's attitudes about rural practice and perceptions of salient others' (eg, spouse's) attitudes about rural practice and rural living. Narrative literature review of scholarship in predicting and understanding predictors and correlates of rural physician retention. The TRA model provides a useful conceptual model to organize the literature on rural physician retention. Physicians' subjective norms regarding rural practice are an important source of influence in the decision to remain or leave one's position, and this relation should be more fully examined in future research.

Comparison of qualitative and quantitative imaging characteristics of [11C]PiB and [18F]flutemetamol in normal control and Alzheimer's subjects.

Science.gov (United States)

Mountz, James M; Laymon, Charles M; Cohen, Ann D; Zhang, Zheng; Price, Julie C; Boudhar, Sanaa; McDade, Eric; Aizenstein, Howard J; Klunk, William E; Mathis, Chester A

2015-01-01

Neuritic amyloid plaques and neurofibrillary tangles, the hallmark pathologic lesions of Alzheimer's disease, are thought to develop before the symptoms of brain failure are clinically detectable. Imaging methods capable of detecting the presence of neuritic amyloid plaques should improve a clinician's ability to identify Alzheimer's disease during the earliest symptomatic phase and to identify at-risk individuals presymptomatically. Currently the best studied amyloid imaging ligand is [(11)C]Pittsburgh Compound B ([(11)C]PiB). However, the 20-minute half-life of this radiotracer limits its use. This study is designed to evaluate the performance characteristics of [(18)F]flutemetamol and to independently compare results to [(11)C]PiB in the same subjects. Twenty-three subjects, 15 cognitively normal (NL) and 8 with a clinical diagnosis of Alzheimer's Dementia (AD), underwent [(11)C]PiB and [(18)F]flutemetamol PET scans within 28 days of study enrollment. We studied both normal and AD subjects to assess the uptake characteristics across a range of amyloid positivity. Blinded visual reads were conducted by five raters. Correlation analyses were performed between cortical SUVR for the two tracers and also between rater scores and SUVR for each tracer. Overall reader accuracy for classifying scans as amyloid positive or negative was determined for each tracer using SUVR classification as the standard. The linear correlation coefficient between global cortical SUVR for the two tracers was R(2) = 0.85, indicating that both tracers have similar retention characteristics. The two tracers were well correlated for rater-determined AD-like positivity (Cohen κ = 0.82). Averaged visual ratings and global cortical SUVR disagreed on their classification in 2/23 [(11)C]PiB scans and 4/23 [(18)F]flutemetamol scans. [(11)C]PiB and [(18)F]flutemetamol have similar retention characteristics across a range of amyloid negative to positive subjects. Both tracers performed similarly when

White matter connectivity and Internet gaming disorder

Science.gov (United States)

Jeong, Bum Seok; Han, Doug Hyun; Kim, Sun Mi; Lee, Sang Won; Renshaw, Perry F.

2017-01-01

Internet use and on-line game play stimulate corticostriatal-limbic circuitry in both healthy subjects and subjects with Internet gaming disorder (IGD). We hypothesized that increased fractional anisotropy (FA) with decreased radial diffusivity (RD) would be observed in IGD subjects, compared with healthy control subjects, and that these white matter indices would be associated with clinical variables including duration of illness and executive function. We screened 181 male patients in order to recruit a large number (n = 58) of IGD subjects without psychiatric co-morbidity as well as 26 male healthy comparison subjects. Multiple diffusion-weighted images were acquired using a 3.0 Tesla magnetic resonance imaging scanner. Tract-based spatial statistics was applied to compare group differences in diffusion tensor imaging (DTI) metrics between IGD and healthy comparison subjects. IGD subjects had increased FA values within forceps minor, right anterior thalamic radiation, right corticospinal tract, right inferior longitudinal fasciculus, right cingulum to hippocampus and right inferior fronto-occipital fasciculus (IFOF) as well as parallel decreases in RD value within forceps minor, right anterior thalamic radiation and IFOF relative to healthy control subjects. In addition, the duration of illness in IGD subjects was positively correlated with the FA values (integrity of white matter fibers) and negatively correlated with RD scores (diffusivity of axonal density) of whole brain white matter. In IGD subjects without psychiatric co-morbidity, our DTI results suggest that increased myelination (increased FA and decreased RD values) in right-sided frontal fiber tracts may be the result of extended game play. PMID:25899390

Consideration of age-dependent radium retention in people on the basis of the beagle model

International Nuclear Information System (INIS)

Parks, N.J.; Keane, A.T.

1981-01-01

This paper examines in humans the proposition emanating from studies in beagles that long-term retention of radium varies in proportion to the calcium addition rate at the time of intake. Because data on the calcium addition rate in younger humans were fragmentary, human calcium-addition rates were scaled from those in beagles, the relative calcium accretion rates in the two species at equivalent stages of skeletal growth providing the scaling factor. The variation of radium retention with age was determined by fitting a modified power function to data on the retention of radium from about 30 to 15,000 days following a series of therapeutic injections of 226 Ra in humans ranging in age from 18 to 63 yr. The fractional retention R at t days following a single injection of 226 Ra was described by R = (1 + t/d) - 0 44 . The age-dependent time constant d in the retention function was found to be proportional to the calcium addition rate at the time of injection in subjects receiving 226 Ra

Evidence for Functional Networks within the Human Brain's White Matter.

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Peer, Michael; Nitzan, Mor; Bick, Atira S; Levin, Netta; Arzy, Shahar

2017-07-05

Investigation of the functional macro-scale organization of the human cortex is fundamental in modern neuroscience. Although numerous studies have identified networks of interacting functional modules in the gray-matter, limited research was directed to the functional organization of the white-matter. Recent studies have demonstrated that the white-matter exhibits blood oxygen level-dependent signal fluctuations similar to those of the gray-matter. Here we used these signal fluctuations to investigate whether the white-matter is organized as functional networks by applying a clustering analysis on resting-state functional MRI (RSfMRI) data from white-matter voxels, in 176 subjects (of both sexes). This analysis indicated the existence of 12 symmetrical white-matter functional networks, corresponding to combinations of white-matter tracts identified by diffusion tensor imaging. Six of the networks included interhemispheric commissural bridges traversing the corpus callosum. Signals in white-matter networks correlated with signals from functional gray-matter networks, providing missing knowledge on how these distributed networks communicate across large distances. These findings were replicated in an independent subject group and were corroborated by seed-based analysis in small groups and individual subjects. The identified white-matter functional atlases and analysis codes are available at http://mind.huji.ac.il/white-matter.aspx Our results demonstrate that the white-matter manifests an intrinsic functional organization as interacting networks of functional modules, similarly to the gray-matter, which can be investigated using RSfMRI. The discovery of functional networks within the white-matter may open new avenues of research in cognitive neuroscience and clinical neuropsychiatry. SIGNIFICANCE STATEMENT In recent years, functional MRI (fMRI) has revolutionized all fields of neuroscience, enabling identifications of functional modules and networks in the human

Future Retention of the Marine Corps Top Performing Aviators

Science.gov (United States)

2016-06-10

balance, and Aviator Continuation Pay. 15. SUBJECT TERMS USMC Aviator Retention, USMC Aviation Manpower, Marine Corps Talent Management , Marine Corps...Wing Aircraft: Includes AH-1, UH-1, and CH-53 platforms. Talent Management : The process through which employers anticipate and meet their needs for...a bias due to his experience as an executive officer responsible for the talent management of company grade WTI aviators. All attempts have been

Condensed matter physics

CERN Document Server

Isihara, A

2007-01-01

More than a graduate text and advanced research guide on condensed matter physics, this volume is useful to plasma physicists and polymer chemists, and their students. It emphasizes applications of statistical mechanics to a variety of systems in condensed matter physics rather than theoretical derivations of the principles of statistical mechanics and techniques. Isihara addresses a dozen different subjects in separate chapters, each designed to be directly accessible and used independently of previous chapters. Topics include simple liquids, electron systems and correlations, two-dimensional

Urinary Analysis of Fluid Retention in the General Population: A Cross-Sectional Study.

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Robert G Hahn

Full Text Available Renal conservation (retention of fluid might affect the outcome of hospital care and can be indicated by increased urinary concentrations of metabolic waste products. We obtained a reference material for further studies by exploring the prevalence of fluid retention in a healthy population.Spot urine sampling was performed in 300 healthy hospital workers. A previously validated algorithm summarized the urine-specific gravity, osmolality, creatinine, and color to a fluid retention index (FRI, where 4.0 is the cut-off for fluid retention consistent with dehydration. In 50 of the volunteers, we also studied the relationships between FRI, plasma osmolality, and water-retaining hormones.The cut-off for fluid retention (FRI ≥ 4.0 was reached by 38% of the population. No correlation was found between the FRI and the time of the day of urine sample collection, and the FRI was only marginally correlated with the time period spent without fluid intake. Volunteers with fluid retention were younger, generally men, and more often had albuminuria (88% vs. 34%, P < 0.001. Plasma osmolality and plasma sodium were somewhat higher in those with a high FRI (mean 294.8 vs. 293.4 mosmol/kg and 140.3 vs. 139.9 mmol/l. Plasma vasopressin was consistently below the limit of detection, and the plasma cortisol, aldosterone, and renin concentrations were similar in subjects with a high or low FRI. The very highest FRI values (≥ 5.0, N = 61 were always accompanied by albuminuria.Fluid retention consistent with moderate dehydration is common in healthy staff working in a Swedish hospital.

Rainwater runoff retention on an aged intensive green roof.

Science.gov (United States)

Speak, A F; Rothwell, J J; Lindley, S J; Smith, C L

2013-09-01

Urban areas are characterised by large proportions of impervious surfaces which increases rainwater runoff and the potential for surface water flooding. Increased precipitation is predicted under current climate change projections, which will put further pressure on urban populations and infrastructure. Roof greening can be used within flood mitigation schemes to restore the urban hydrological balance of cities. Intensive green roofs, with their deeper substrates and higher plant biomass, are able to retain greater quantities of runoff, and there is a need for more studies on this less common type of green roof which also investigate the effect of factors such as age and vegetation composition. Runoff quantities from an aged intensive green roof in Manchester, UK, were analysed for 69 rainfall events, and compared to those on an adjacent paved roof. Average retention was 65.7% on the green roof and 33.6% on the bare roof. A comprehensive soil classification revealed the substrate, a mineral soil, to be in good general condition and also high in organic matter content which can increase the water holding capacity of soils. Large variation in the retention data made the use of predictive regression models unfeasible. This variation arose from complex interactions between Antecedant Dry Weather Period (ADWP), season, monthly weather trends, and rainfall duration, quantity and peak intensity. However, significantly lower retention was seen for high rainfall events, and in autumn, which had above average rainfall. The study period only covers one unusually wet year, so a longer study may uncover relationships to factors which can be applied to intensive roofs elsewhere. Annual rainfall retention for Manchester city centre could be increased by 2.3% by a 10% increase in intensive green roof construction. The results of this study will be of particular interest to practitioners implementing greenspace adaptation in temperate and cool maritime climates. Copyright © 2013

Long-term retention of radium in female former dial workers

International Nuclear Information System (INIS)

Rundo, J.; Keane, A.T.; Essling, M.A.

1984-01-01

The results of measurements of radium contents in 13 women made over 20 years or more were used to measure radium retention. The women were all employed at different studios of the same Illinois plant as luminous dial workers for up to 4 years. The data for each woman were fitted to an exponential function of time, yielding a biological half-life of approximately 30 to 60 years. There was a strong negative correlation between elimination rate and body content, suggesting an effect of radiation of bone resorption or remodelling. A strong negative correlation was observed between the elimination rate and the reduced x-ray score, a measure of bone damage observed radiographically in the same subjects. Age at first exposure and duration of exposure were not significantly correlated with the elimination rate. The concentration of radium in soft tissues from eight other subjects, expressed as a percentage of the terminal radium content, decreased with increasing body content, providing further evidence that radiation was affecting the elimination rate. An effect of radiation on the late retention of radium has been demonstrated. 10 references, 4 figures, 2 tables

The Specific Heat of Matter at Low Temperatures

CERN Document Server

Tari, A

2003-01-01

Recent discoveries of new materials and improvements in calorimetric techniques have given new impetus to the subject of specific heat. Nevertheless, there is a serious lack of literature on the subject. This invaluable book, which goes some way towards remedying that, is concerned mainly with the specific heat of matter at ordinary temperatures. It discusses the principles that underlie the theory of specific heat and considers a number of theoretical models in some detail. The subject matter ranges from traditional materials to those recently discovered - heavy fermion compounds, high temper

Surface retention and photochemical reactivity of the diphenylether herbicide oxyfluorfen.

Science.gov (United States)

Scrano, Laura; Bufo, Sabino A; Cataldi, Tommaso R I; Albanis, Triantafyllos A

2004-01-01

The photochemical behavior of oxyfluorfen [2-chloro-1-(3-etoxy-4-nitrophenoxy)-4-(trifluoromethyl) benzene] on two Greek soils was investigated. Soils were sampled from Nea Malgara and Preveza regions, characterized by a different organic matter content. Soils were spiked with the diphenyl-ether herbicide and irradiation experiments were performed either in the laboratory with a solar simulator (xenon lamp) or outside, under natural sunlight irradiation; other soil samples were kept in the dark to control the retention reaction. Kinetic parameters of both retention and photochemical reactions were calculated using zero-, first- and second- (Langmuir-Hinshelwood) order equations, and best fit was checked through statistical analysis. The soil behaviors were qualitatively similar but quantitatively different, with the soil sampled from the Nea Malgara region much more sorbent as compared with Preveza soil. All studied reactions followed second-order kinetics and photochemical reactions were influenced by retaining capability of the soils. The contributions of the photochemical processes to the global dissipation rates were also calculated. Two main metabolites were identified as 2-chloro-1-(3-ethoxy-4-hydroxyphenoxy)-4-(trifluoromethyl)benzene and 2-chloro-1- (3-hydroxy-4-nitrophenoxy)-4-(trifluoromethyl)benzene.

The retention of [99mTc]-d,l-HM-PAO in the human brain after intracarotid bolus injection

DEFF Research Database (Denmark)

Lassen, N A; Andersen, A R; Friberg, L

1988-01-01

[99mTc]-d,l-HM-PAO (HM-PAO) was injected rapidly into the internal carotid artery and its retention in the brain was recorded by external scintillation cameras in eight human subjects. A model is described based on three compartments: the lipophilic tracer in the blood pool of the brain, the lipo......[99mTc]-d,l-HM-PAO (HM-PAO) was injected rapidly into the internal carotid artery and its retention in the brain was recorded by external scintillation cameras in eight human subjects. A model is described based on three compartments: the lipophilic tracer in the blood pool of the brain...

Urinary Retention Associated with Stroke.

Science.gov (United States)

Umemura, Takeru; Ohta, Hirotsugu; Yokota, Akira; Yarimizu, Shiroh; Nishizawa, Shigeru

Patients often exhibit urinary retention following a stroke. Various neuropathological and animal studies have implicated the medulla oblongata, pons, limbic system, frontal lobe as areas responsible for micturition control, although the exact area responsible for urinary retention after stroke is not clear. The purpose of this study was to identify the stroke area responsible for urinary retention by localizing the areas where strokes occur. We assessed 110 patients with cerebral infarction and 27 patients with cerebral hemorrhage (78 men, 59 women; mean age, 73.0 years) who had been admitted to our hospital between October, 2012 and September, 2013. We used computed tomography (CT) and magnetic resonance imaging (MRI) to investigate the stroke location, and evaluated whether post-stroke urinary retention occurred. Twelve (8.8%) of the 137 patients (7 men, 5 women; mean age, 78.8 years) exhibited urinary retention after a stroke. Stroke occurred in the right/left dominant hemisphere in 7 patients; nondominant hemisphere in 1; cerebellum in 3; and brainstem in 1. Strokes in the dominant hemisphere were associated with urinary retention (P = 0.0314), particularly in the area of the insula (P < 0.01). We concluded that stroke affecting the insula of the dominant hemisphere tends to cause urinary retention.

Gas expulsion vs gas retention in young stellar clusters II: effects of cooling and mass segregation

Science.gov (United States)

Silich, Sergiy; Tenorio-Tagle, Guillermo

2018-05-01

Gas expulsion or gas retention is a central issue in most of the models for multiple stellar populations and light element anti-correlations in globular clusters. The success of the residual matter expulsion or its retention within young stellar clusters has also a fundamental importance in order to understand how star formation proceeds in present-day and ancient star-forming galaxies and if proto-globular clusters with multiple stellar populations are formed in the present epoch. It is usually suggested that either the residual gas is rapidly ejected from star-forming clouds by stellar winds and supernova explosions, or that the enrichment of the residual gas and the formation of the second stellar generation occur so rapidly, that the negative stellar feedback is not significant. Here we continue our study of the early development of star clusters in the extreme environments and discuss the restrictions that strong radiative cooling and stellar mass segregation provide on the gas expulsion from dense star-forming clouds. A large range of physical initial conditions in star-forming clouds which include the star-forming cloud mass, compactness, gas metallicity, star formation efficiency and effects of massive stars segregation are discussed. It is shown that in sufficiently massive and compact clusters hot shocked winds around individual massive stars may cool before merging with their neighbors. This dramatically reduces the negative stellar feedback, prevents the development of the global star cluster wind and expulsion of the residual and the processed matter into the ambient interstellar medium. The critical lines which separate the gas expulsion and the gas retention regimes are obtained.

Recruitment and Retention of LGBTIQ Astronomers

Science.gov (United States)

Dixon, William Van Dyke

2012-01-01

While lesbian, gay, bisexual, transgender, intersex, or questioning (LGBTIQ) astronomers face many of the same workplace challenges as women and racial/ethnic minorities, from implicit bias to overt discrimination, other challenges are unique to this group. An obvious example is the absence at many institutions of health insurance and other benefits for the same-sex domestic partners of their employees. More subtle is the psychological toll paid by LGBTIQ astronomers who remain "in the closet," self-censoring every statement about their personal lives. Paradoxically, the culture of the physical sciences, in which sexuality, gender identity, and gender expression are considered irrelevant, can discourage their discussion, further isolating LGBTIQ researchers. Addressing these challenges is not just a matter of fairness; it is an essential tool in the recruitment and retention of the brightest researchers and in assuring their productivity. We will discuss these issues and what individuals and departments can to make their institutions more welcoming to their LGBTIQ colleagues.

Molybdenum isotope fractionation during adsorption to organic matter

Science.gov (United States)

King, Elizabeth K.; Perakis, Steven; Pett-Ridge, Julie C.

2018-01-01

Organic matter is of emerging interest as a control on molybdenum (Mo) biogeochemistry, and information on isotope fractionation during adsorption to organic matter can improve interpretations of Mo isotope variations in natural settings. Molybdenum isotope fractionation was investigated during adsorption onto insolubilized humic acid (IHA), a surrogate for organic matter, as a function of time (2–170 h) and pH (2–7). For the time series experiment performed at pH 4.2, the average Mo isotope fractionation between the solution and the IHA (Δ98Mosolution-IHA) was 1.39‰ (± 0.16‰, 2σ, based on 98Mo/95Mo relative to the NIST 3134 standard) at steady state. For the pH series experiment, Mo adsorption decreased as pH increased from 2.0 to 6.9, and the Δ98Mosolution-IHA increased from 0.82‰ to 1.79‰. We also evaluated natural Mo isotope patterns in precipitation, foliage, organic horizon, surface mineral soil, and bedrock from 12 forested sites in the Oregon Coast Range. The average Mo isotope offset observed between precipitation and organic (O) horizon soil was 2.1‰, with light Mo isotopes adsorbing preferentially to organic matter. Fractionation during adsorption to organic matter is similar in magnitude and direction to prior observations of Mo fractionation during adsorption to Fe- and Mn- (oxyhydr)oxides. Our finding that organic matter influences Mo isotope composition has important implications for the role of organic matter as a driver of trace metal retention and isotopic fractionation.

Associative Learning during Early Adulthood Enhances Later Memory Retention in Honeybees

Science.gov (United States)

Arenas, Andrés; Fernández, Vanesa M.; Farina, Walter M.

2009-01-01

Background Cognitive experiences during the early stages of life play an important role in shaping the future behavior in mammals but also in insects, in which precocious learning can directly modify behaviors later in life depending on both the timing and the rearing environment. However, whether olfactory associative learning acquired early in the adult stage of insects affect memorizing of new learning events has not been studied yet. Methodology Groups of adult honeybee workers that experienced an odor paired with a sucrose solution 5 to 8 days or 9 to 12 days after emergence were previously exposed to (i) a rewarded experience through the offering of scented food, or (ii) a non-rewarded experience with a pure volatile compound in the rearing environment. Principal Findings Early rewarded experiences (either at 1–4 or 5–8 days of adult age) enhanced retention performance in 9–12-day-conditioned bees when they were tested at 17 days of age. The highest retention levels at this age, which could not be improved with prior rewarded experiences, were found for memories established at 5–8 days of adult age. Associative memories acquired at 9–12 days of age showed a weak effect on retention for some pure pre-exposed volatile compounds; whereas the sole exposure of an odor at any younger age did not promote long-term effects on learning performance. Conclusions The associative learning events that occurred a few days after adult emergence improved memorizing in middle-aged bees. In addition, both the timing and the nature of early sensory inputs interact to enhance retention of new learning events acquired later in life, an important matter in the social life of honeybees. PMID:19956575

Associative learning during early adulthood enhances later memory retention in honeybees.

Directory of Open Access Journals (Sweden)

Andrés Arenas

Full Text Available BACKGROUND: Cognitive experiences during the early stages of life play an important role in shaping the future behavior in mammals but also in insects, in which precocious learning can directly modify behaviors later in life depending on both the timing and the rearing environment. However, whether olfactory associative learning acquired early in the adult stage of insects affect memorizing of new learning events has not been studied yet. METHODOLOGY: Groups of adult honeybee workers that experienced an odor paired with a sucrose solution 5 to 8 days or 9 to 12 days after emergence were previously exposed to (i a rewarded experience through the offering of scented food, or (ii a non-rewarded experience with a pure volatile compound in the rearing environment. PRINCIPAL FINDINGS: Early rewarded experiences (either at 1-4 or 5-8 days of adult age enhanced retention performance in 9-12-day-conditioned bees when they were tested at 17 days of age. The highest retention levels at this age, which could not be improved with prior rewarded experiences, were found for memories established at 5-8 days of adult age. Associative memories acquired at 9-12 days of age showed a weak effect on retention for some pure pre-exposed volatile compounds; whereas the sole exposure of an odor at any younger age did not promote long-term effects on learning performance. CONCLUSIONS: The associative learning events that occurred a few days after adult emergence improved memorizing in middle-aged bees. In addition, both the timing and the nature of early sensory inputs interact to enhance retention of new learning events acquired later in life, an important matter in the social life of honeybees.

Girl Scouts and Subject Matter Experts: What’s the Connection?

Science.gov (United States)

Harman, Pamela; Girls Scouts of Northern California, Girl Scouts USA, Astronomical Society of the Pacifica, Univeristy of Arizona, and ARIES Scientific.

2018-01-01

Reaching for the Stars: NASA Science for Girl Scouts (Girl Scout Stars) fosters interaction between Girl Scouts and NASA Subject Matter Experts (SMEs), disseminates NASA STEM education-related resources, and engages Girl Scouts in NASA science and programs through space science badges and summer camps.A space science badge is in development for each of the six levels of Girl Scouts: Daisies, Grades K – 1; Brownies, Grades 2 -3; Juniors, Grades 4 -5; Cadettes, Grades 6 -8; Seniors, Grades 9 -10; and Ambassadors, Grades 11 -12. Indirectly, SMEs will reach tens of thousands of girls through the badges. SETI Institute SMEs Institute and SME Co-Is located at ARIES Scientific, Astronomical Society of the Pacific, University of Arizona, and Girl Scouts of Northern California developed and modified astronomy activities for the Girl Scouts USA badge writers to finesse into the Girl Scout formats. Revisions are reviewed by SMEs for accuracy. Each badge includes a step option that encourages girls to connect with SMEs, and recommendations for volunteers.A total of 127 girls from 31 states and the District of Columbia attendedTotal Eclipse Destination Camps at three locations. SMEs led activities and tours, inspiring girls to consider STEM careers. University of Arizona (U of A) SMEs lead Astronomy Camp for Volunteers, enabling volunteers to lead and inspire Girl Scouts in their respective Girl Scout Councils. A Destination Camp for Girl Scouts was also held at U of A. Girls experience authentic astronomy, learning how to collect and analyze data.Eleven teams comprised of two Girl Scouts, a volunteer or Council Staff, and an amateur astronomer attended Astronomy Club Camp, held at NASA GSFC. SMEs delivered science content. The girls will lead the formation of astronomy clubs in their councils, and will train their successors. SMEs will present and coach the clubs during monthly webinars.This presentation will highlight success and discuss lessons learned that are applicable

Absorption and retention of selenium from shrimps in man

DEFF Research Database (Denmark)

Bugel, S. H.; Sandstrom, B.; Larsen, Erik Huusfeldt

2001-01-01

This study was undertaken to evaluate the bioavailability of selenium in shrimps, a possible good source of selenium, by measurements of the absorption and retention of selenium and the effects on plasma selenium concentration and glutathione peroxidase activity. Twelve healthy young subjects (9F...... of the study, after 2, 4, and 6 weeks. The selenium intake increased from 39.4 +/- 15.3 mug/d to 127 +/- 5.5 mug/d with the addition of shrimps. The apparent absorption of selenium from shrimps was 83 +/- 4%, Faecal and urinary selenium excretion was 32.5 +/- 17.0 mug/d and 21.2 +/- 9.0 mug/d, re spectively...... and the total retention of selenium was 3.1 +/- 1.1 mg. Plasma selenium concentrations were 95.2 +/- 9.7 mug/L and 101.5 +/- 9.7 mug/L before and after six weeks of shrimp intake, respectively (p...

The Effects of Cooperative Learning on the Academic Achievement and Knowledge Retention

Science.gov (United States)

Tran, Van Dat

2014-01-01

This experimental study investigated the effects of cooperative learning on the achievement and knowledge retention of 110 first-year primary education students toward the psychology subject over the eight weeks of instruction at An Giang University. These tertiary students were divided into two matched groups of 55 to be taught by the same…

17 CFR 140.735-2a - Prohibited interests.

Science.gov (United States)

2010-04-01

... bars an employee from participating in any particular matter that will have a direct and predictable... subject to the provisions of paragraphs (d) and (f) of this section. (d) Retention or passive acquisition... matter that will have a direct and predictable effect on the financial interest in question. Any...

The interrelationship between subject matter and school gardens

DEFF Research Database (Denmark)

Christensen, Jacob Højgaard; Wistoft, Karen

2018-01-01

This article maps out existing research regarding the effectiveness of integrated teaching in school gardens, i.e. including the math, languages and science subjects with their related objectives and curricula in school garden teaching and vice versa. The article is based on a literature review...... that concludes that school gardens have a predominantly positive influence on students’ learning outcome. However, there are a few school garden programmes that have the same or even a less beneficial influence on students’ learning outcome than traditional teaching. Thus, school gardens do not have...... an unequivocally positive academic learning effect. The review extracts and discusses some of the factors that are consistently emphasized in the research literature as central to ensuring successful subject integration in school gardens. Taking these as a point of departure, it is concluded that developing...

Military Retention. A Comparative Outlook

Directory of Open Access Journals (Sweden)

Vasile Sminchise

2016-06-01

Full Text Available One of the main goals for human resources management structures and for armed forces leaders is to maintain all necessary personnel, both qualitatively and quantitatively for operational needs or for full required capabilities. The retention of military personnel is essential to keep morale and unit readiness and to reduce the costs for recruiting, training, replacement of manpower. Retention rates depend not only on money or other social measures. The goal for retention is to keep in use the most valuable resource that belongs to an organization: the human beings and their knowledge. The aim pf this paper is to provide a comparative analysis of retention measures in various countries based on Research and Technology Organisation report released in 2007 and, thus, provide more examples of retention measures as far as the Romanian military system is concerned.

Retention of Root Canal Posts

DEFF Research Database (Denmark)

Sahafi, A; Benetti, Ana Raquel; Flury, S

2015-01-01

The aim of this study was to investigate the effect of the cement film thickness of a zinc phosphate or a resin cement on retention of untreated and pretreated root canal posts. Prefabricated zirconia posts (CosmoPost: 1.4 mm) and two types of luting cements (a zinc phosphate cement [DeTrey Zinc...... received tribochemical silicate coating according to the manufacturer's instructions. Posts were then luted in the prepared root canals (n=30 per group). Following water storage at 37°C for seven days, retention of the posts was determined by the pull-out method. Irrespective of the luting cement......, pretreatment with tribochemical silicate coating significantly increased retention of the posts. Increased cement film thickness resulted in decreased retention of untreated posts and of pretreated posts luted with zinc phosphate cement. Increased cement film thickness had no influence on retention...

Retention of Basic Life Support in Laypeople: Mastery Learning vs. Time-based Education.

Science.gov (United States)

Boet, Sylvain; Bould, M Dylan; Pigford, Ashlee-Ann; Rössler, Bernhard; Nambyiah, Pratheeban; Li, Qi; Bunting, Alexandra; Schebesta, Karl

2017-01-01

To compare the effectiveness of a mastery learning (ML) versus a time-based (TB) BLS course for the acquisition and retention of BLS knowledge and skills in laypeople. After ethics approval, laypeople were randomized to a ML or TB BLS course based on the American Heart Association (AHA) Heartsaver course. In the ML group, subjects practiced and received feedback at six BLS stations until they reached a pre-determined level of performance. The TB group received a standard AHA six-station BLS course. All participants took the standard in-course BLS skills test at the end of their course. BLS skills and knowledge were tested using a high-fidelity scenario and knowledge questionnaire upon course completion (immediate post-test) and after four months (retention test). Video recorded scenarios were assessed by two blinded, independent raters using the AHA skills checklist. Forty-three subjects were included in analysis (23ML;20TB). For primary outcome, subjects' performance did not change after four months, regardless of the teaching modality (TB from (median[IQR]) 8.0[6.125;8.375] to 8.5[5.625;9.0] vs. ML from 8.0[7.0;9.0] to 7.0[6.0;8.0], p = 0.12 for test phase, p = 0.21 for interaction between effect of teaching modality and test phase). For secondary outcomes, subjects acquired knowledge between pre- and immediate post-tests (p < 0.005), and partially retained the acquired knowledge up to four months (p < 0.005) despite a decrease between immediate post-test and retention test (p = 0.009), irrespectively of the group (p = 0.59) (TB from 63.3[48.3;73.3] to 93.3[81.7;100.0] and then 93.3[81.7;93.3] vs. ML from 60.0[46.7;66.7] to 93.3[80.0;100.0] and then 80.0[73.3;93.3]). Regardless of the group after 4 months, chest compression depth improved (TB from 39.0[35.0;46.0] to 48.5[40.25;58.0] vs. ML from 40.0[37.0;47.0] to 45.0[37.0;52.0]; p = 0.012), but not the rate (TB from 118.0[114.0;125.0] to 120.5[113.0;129.5] vs. ML from 119.0[113.0;130.0] to 123.0[102.0;132.0]; p

White matter integrity in kleptomania: A pilot study

OpenAIRE

Grant, Jon E.; Correia, Stephen; Brennan-Krohn, Thea

2006-01-01

This study's goal was to examine microstructural organization of frontal white matter in kleptomania. Ten females with DSM-IV kleptomania and 10 female controls underwent diffusion tensor imaging. Inferior frontal white matter was the a priori region of interest. Trace and fractional anisotropy (FA) were also calculated for frontal and posterior cortical regions in both subject groups. Kleptomania subjects had significantly higher mean frontal Trace, and significantly lower mean frontal FA th...

Job embeddedness and nurse retention.

Science.gov (United States)

Reitz, O Ed; Anderson, Mary Ann; Hill, Pamela D

2010-01-01

Nurse retention is a different way of conceptualizing the employer-employee relationship when compared with turnover. Job embeddedness (JE), a construct based on retention, represents the sum of reasons why employees remain at their jobs. However, JE has not been investigated in relation to locale (urban or rural) or exclusively with a sample of registered nurses (RNs). The purpose of this study was to determine what factors (JE, age, gender, locale, and income) help predict nurse retention. A cross-sectional mailed survey design was used with RNs in different locales (urban or rural). Job embeddedness was measured by the score on the composite, standardized instrument. Nurse retention was measured by self-report items concerning intent to stay. A response rate of 49.3% was obtained. The typical respondent was female (96.1%), white, non-Hispanic (87.4%), and married (74.9%). Age and JE were predictive of nurse retention and accounted for 26% of the explained variance in intent to stay. Although age was a significant predictor of intent to stay, it accounted for only 1.4% of the variance while JE accounted for 24.6% of the variance of nurse retention (as measured by intent to stay). Older, more "embedded" nurses are more likely to remain employed in their current organization. Based on these findings, JE may form the basis for the development of an effective nurse retention program.

Calculation of retention time tolerance windows with absolute confidence from shared liquid chromatographic retention data.

Science.gov (United States)

Boswell, Paul G; Abate-Pella, Daniel; Hewitt, Joshua T

2015-09-18

Compound identification by liquid chromatography-mass spectrometry (LC-MS) is a tedious process, mainly because authentic standards must be run on a user's system to be able to confidently reject a potential identity from its retention time and mass spectral properties. Instead, it would be preferable to use shared retention time/index data to narrow down the identity, but shared data cannot be used to reject candidates with an absolute level of confidence because the data are strongly affected by differences between HPLC systems and experimental conditions. However, a technique called "retention projection" was recently shown to account for many of the differences. In this manuscript, we discuss an approach to calculate appropriate retention time tolerance windows for projected retention times, potentially making it possible to exclude candidates with an absolute level of confidence, without needing to have authentic standards of each candidate on hand. In a range of multi-segment gradients and flow rates run among seven different labs, the new approach calculated tolerance windows that were significantly more appropriate for each retention projection than global tolerance windows calculated for retention projections or linear retention indices. Though there were still some small differences between the labs that evidently were not taken into account, the calculated tolerance windows only needed to be relaxed by 50% to make them appropriate for all labs. Even then, 42% of the tolerance windows calculated in this study without standards were narrower than those required by WADA for positive identification, where standards must be run contemporaneously. Copyright © 2015 Elsevier B.V. All rights reserved.

Size exclusion and anion exchange high performance liquid chromatography for characterizing metals bound to marine dissolved organic matter

International Nuclear Information System (INIS)

García-Otero, Natalia; Bermejo-Barrera, Pilar; Moreda-Piñeiro, Antonio

2013-01-01

Highlights: ► Fractionation methods for assessing metals bound to marine DOM were developed. ► SEC and AEC with UV detection and hyphenated with inductively coupled plasma-mass spectrometry were used. ► SEC-UV showed marine DOM of molecular weights from 16 to 1 kDa. ► Cobalt, manganese, strontium and zinc are bound to marine DOM. - Abstract: Size exclusion chromatography (SEC) followed by anion exchange chromatography (AEC) hyphenated with inductively coupled plasma-mass spectrometry (ICP-MS) was applied for fractionating metals bound to marine dissolved organic matter (DOM). Surface seawater samples (100 L) were subjected to tangential flow ultrafiltration (10,000 Da cut off) for isolating and pre-concentrating dissolved large molecules. The isolated fraction (retentate) consisted of 1 L, which was further freeze-dried and re-dissolved to 250 mL with ultrapure water. After HI Trap desalting of the re-dissolved retentate, SEC with UV detection showed marine DOM ranging from 6.5 kDa (lower than the permeable volume of the SEC column) to 16 kDa. A further characterization of this fraction by AEC with UV detection revealed the existence of four groups of macromolecules exhibiting retention times of 2.3, 2.8, 4.5 and 14.0 min. AEC hyphenated with ICP-MS showed the presence of strontium and zinc in the first AE fraction isolated from the SEC fraction; while manganese was found to be bound to the second AE fraction. Cobalt was found to be bound to molecules comprising the third AE fraction.

Posttreatment and retention outcomes with and without periodontally accelerated osteogenic orthodontics assessed using ABO objective grading system

Directory of Open Access Journals (Sweden)

Donald J Ferguson

2016-01-01

Full Text Available Background: The posttreatment and retention outcomes following nonextraction orthodontic therapy, with and without corticotomy, were assessed using the American Board of Orthodontists objective grading system (OGS. Purpose: The purpose was to determine if the course of retention was any different following alveolar decortication and augmentation bone grafting, i.e., periodontally accelerated osteogenic orthodontics (PAOO. Materials and Methods: Study casts and panoramic radiographs of patients with and without PAOO (28 subjects each were selected on the basis of the following: (1 comprehensive nonextraction orthodontic treatment using straight wire edgewise appliances for Class I crowding, (2 availability of immediate posttreatment records and retention records at least 1 year post de-bracketing, and (3 use of Hawley removable retainers with similar wearing instructions. Results: Independent and paired t-test statistical testing revealed the following: (1 Posttreatment orthodontic outcomes were the same, with or without corticotomy. (2 During retention, 5 of 8 ABO grading criteria improved for the sample without corticotomy, and 6 of 8 ABO grading criteria improved for the group with corticotomy. (3 Retention outcome scores were lower (better for alignment and marginal ridges in the corticotomy-facilitated group. (4 The total score was significantly lower (better for the corticotomy group at retention and the increment of total score change decreased (improved significantly more during retention following corticotomy. Conclusions: The retention phase was more favorable following corticotomy because the amount of OGS total score change demonstrated a significantly improved retention outcome following PAOO therapy.

An Experimental Study on the Impact of Different-frequency Elastic Waves on Water Retention Curve

Science.gov (United States)

Deng, J. H.; Dai, J. Y.; Lee, J. W.; Lo, W. C.

2017-12-01

ABSTEACTOver the past few decades, theoretical and experimental studies on the connection between elastic wave attributes and the physical properties of a fluid-bearing porous medium have attracted the attention of many scholars in fields of porous medium flow and hydrogeology. It has been previously determined that the transmission of elastic waves in a porous medium containing two immiscible fluids will have an effect on the water retention curve, but it has not been found that the water retention curve will be affected by the frequency of elastic vibration waves or whether the effect on the soil is temporary or permanent. This research is based on a sand box test in which the soil is divided into three layers (a lower, middle, and upper layer). In this case, we discuss different impacts on the water retention curve during the drying process under sound waves (elastic waves) subject to three frequencies (150Hz, 300Hz, and 450Hz), respectively. The change in the water retention curve before and after the effect is then discussed. In addition, how sound waves affect the water retention curve at different depths is also observed. According to the experimental results, we discover that sound waves can cause soil either to expand or to contract. When the soil is induced to expand due to sound waves, it can contract naturally and return to the condition it was in before the influence of the sound waves. On the contrary, when the soil is induced to contract, it is unable to return to its initial condition. Due to the results discussed above, it is suggested that sound waves causing soil to expand have a temporary impact while those causing soil to contract have a permanent impact. In addition, our experimental results show how sound waves affect the water retention curve at different depths. The degree of soil expansion and contraction caused by the sound waves will differ at various soil depths. Nevertheless, the expanding or contracting of soil is only subject to the

Nitrogen retention across a gradient of 15N additions to an unpolluted temperate forest soil in Chile

Science.gov (United States)

Perakis, Steven S.; Compton, J.E.; Hedin, L.O.

2005-01-01

Accelerated nitrogen (N) inputs can drive nonlinear changes in N cycling, retention, and loss in forest ecosystems. Nitrogen processing in soils is critical to understanding these changes, since soils typically are the largest N sink in forests. To elucidate soil mechanisms that underlie shifts in N cycling across a wide gradient of N supply, we added 15NH415NO3 at nine treatment levels ranging in geometric sequence from 0.2 kg to 640 kg NA? ha-1A? yr-1 to an unpolluted old-growth temperate forest in southern Chile. We recovered roughly half of tracers in 0-25 cm of soil, primarily in the surface 10 cm. Low to moderate rates of N supply failed to stimulate N leaching, which suggests that most unrecovered 15N was transferred from soils to unmeasured sinks above ground. However, soil solution losses of nitrate increased sharply at inputs > 160 kg NA? ha-1A? yr-1, corresponding to a threshold of elevated soil N availability and declining 15N retention in soil. Soil organic matter (15N in soils at the highest N inputs and may explain a substantial fraction of the 'missing N' often reported in studies of fates of N inputs to forests. Contrary to expectations, N additions did not stimulate gross N cycling, potential nitrification, or ammonium oxidizer populations. Our results indicate that the nonlinearity in N retention and loss resulted directly from excessive N supply relative to sinks, independent of plant-soil-microbial feedbacks. However, N additions did induce a sharp decrease in microbial biomass C:N that is predicted by N saturation theory, and which could increase long-term N storage in soil organic matter by lowering the critical C:N ratio for net N mineralization. All measured sinks accumulated 15N tracers across the full gradient of N supply, suggesting that short-term nonlinearity in N retention resulted from saturation of uptake kinetics, not uptake capacity, in plant, soil, and microbial pools.

Age-related cerebral white matter changes on computed tomography

International Nuclear Information System (INIS)

Fukuda, Hitoshi; Kobayashi, Shotai; Koide, Hiromi; Yamaguchi, Shuhei; Okada, Kazunori; Shimote, Kouichi; Tsunematsu, Tokugoro

1989-01-01

Changes of cerebral white matter on computed cranial tomography related to aging were studied in 70 subjects aged 30 to 94 years. The subjects had no histories of cerebrovascular accidents and no abnormalities in the central nervous system were shown by physical examinations and CT scans. We measured the average attenuation values (CT numbers) of each elliptical region (165 pixels, 0.39cm 2 ) in the bilateral thalamus and twelve areas of deep white matter. Multiple regression analysis was used to assess the effects of age, cranial size and cranial bone CT numbers on the brain CT numbers. We also studied the association between brain CT numbers and brain atrophy, hypertension, diabetes mellitus. CT numbers of frontal white matter surrounding anterior horns decreased with aging in 70 subjects aged 30 to 94 years. No significant correlation between age and brain CT numbers was found in any other region by multivariate analysis, because of the prominent effect of cranial bone CT numbers on brain CT numbers. Although no age-related changes of white matter CT numbers was found in 41 subjects aged 30 to 65 years, there were significant negative correlations between age and white matter CT numbers at all regions in 29 subjects aged 66 to 94 years. Brain atrophy was associated with brain CT numbers. No association was found for hypertension or diabetes mellitus. Brain CT numbers decreased with aging even in neurologically healthy persons in older age. Brain CT numbers also decreased as cerebral atrophy advanced. (author)

Age-related cerebral white matter changes on computed tomography

Energy Technology Data Exchange (ETDEWEB)

Fukuda, Hitoshi; Kobayashi, Shotai; Koide, Hiromi; Yamaguchi, Shuhei; Okada, Kazunori; Shimote, Kouichi; Tsunematsu, Tokugoro

1989-01-01

Changes of cerebral white matter on computed cranial tomography related to aging were studied in 70 subjects aged 30 to 94 years. The subjects had no histories of cerebrovascular accidents and no abnormalities in the central nervous system were shown by physical examinations and CT scans. We measured the average attenuation values (CT numbers) of each elliptical region (165 pixels, 0.39cm/sup 2/) in the bilateral thalamus and twelve areas of deep white matter. Multiple regression analysis was used to assess the effects of age, cranial size and cranial bone CT numbers on the brain CT numbers. We also studied the association between brain CT numbers and brain atrophy, hypertension, diabetes mellitus. CT numbers of frontal white matter surrounding anterior horns decreased with aging in 70 subjects aged 30 to 94 years. No significant correlation between age and brain CT numbers was found in any other region by multivariate analysis, because of the prominent effect of cranial bone CT numbers on brain CT numbers. Although no age-related changes of white matter CT numbers was found in 41 subjects aged 30 to 65 years, there were significant negative correlations between age and white matter CT numbers at all regions in 29 subjects aged 66 to 94 years. Brain atrophy was associated with brain CT numbers. No association was found for hypertension or diabetes mellitus. Brain CT numbers decreased with aging even in neurologically healthy persons in older age. Brain CT numbers also decreased as cerebral atrophy advanced. (author).

The Picmonic(®) Learning System: enhancing memory retention of medical sciences, using an audiovisual mnemonic Web-based learning platform.

Science.gov (United States)

Yang, Adeel; Goel, Hersh; Bryan, Matthew; Robertson, Ron; Lim, Jane; Islam, Shehran; Speicher, Mark R

2014-01-01

Medical students are required to retain vast amounts of medical knowledge on the path to becoming physicians. To address this challenge, multimedia Web-based learning resources have been developed to supplement traditional text-based materials. The Picmonic(®) Learning System (PLS; Picmonic, Phoenix, AZ, USA) is a novel multimedia Web-based learning platform that delivers audiovisual mnemonics designed to improve memory retention of medical sciences. A single-center, randomized, subject-blinded, controlled study was conducted to compare the PLS with traditional text-based material for retention of medical science topics. Subjects were randomly assigned to use two different types of study materials covering several diseases. Subjects randomly assigned to the PLS group were given audiovisual mnemonics along with text-based materials, whereas subjects in the control group were given the same text-based materials with key terms highlighted. The primary endpoints were the differences in performance on immediate, 1 week, and 1 month delayed free-recall and paired-matching tests. The secondary endpoints were the difference in performance on a 1 week delayed multiple-choice test and self-reported satisfaction with the study materials. Differences were calculated using unpaired two-tailed t-tests. PLS group subjects demonstrated improvements of 65%, 161%, and 208% compared with control group subjects on free-recall tests conducted immediately, 1 week, and 1 month after study of materials, respectively. The results of performance on paired-matching tests showed an improvement of up to 331% for PLS group subjects. PLS group subjects also performed 55% greater than control group subjects on a 1 week delayed multiple choice test requiring higher-order thinking. The differences in test performance between the PLS group subjects and the control group subjects were statistically significant (P<0.001), and the PLS group subjects reported higher overall satisfaction with the

Correlation between white matter damage and gray matter lesions in multiple sclerosis patients

Directory of Open Access Journals (Sweden)

Xue-mei Han

2017-01-01

Full Text Available We observed the characteristics of white matter fibers and gray matter in multiple sclerosis patients, to identify changes in diffusion tensor imaging fractional anisotropy values following white matter fiber injury. We analyzed the correlation between fractional anisotropy values and changes in whole-brain gray matter volume. The participants included 20 patients with relapsing-remitting multiple sclerosis and 20 healthy volunteers as controls. All subjects underwent head magnetic resonance imaging and diffusion tensor imaging. Our results revealed that fractional anisotropy values decreased and gray matter volumes were reduced in the genu and splenium of corpus callosum, left anterior thalamic radiation, hippocampus, uncinate fasciculus, right corticospinal tract, bilateral cingulate gyri, and inferior longitudinal fasciculus in multiple sclerosis patients. Gray matter volumes were significantly different between the two groups in the right frontal lobe (superior frontal, middle frontal, precentral, and orbital gyri, right parietal lobe (postcentral and inferior parietal gyri, right temporal lobe (caudate nucleus, right occipital lobe (middle occipital gyrus, right insula, right parahippocampal gyrus, and left cingulate gyrus. The voxel sizes of atrophic gray matter positively correlated with fractional anisotropy values in white matter association fibers in the patient group. These findings suggest that white matter fiber bundles are extensively injured in multiple sclerosis patients. The main areas of gray matter atrophy in multiple sclerosis are the frontal lobe, parietal lobe, caudate nucleus, parahippocampal gyrus, and cingulate gyrus. Gray matter atrophy is strongly associated with white matter injury in multiple sclerosis patients, particularly with injury to association fibers.

Concept of Compound Retention Time for Organic Micro Pollutants in Anaerobic Membrane Bioreactor with Nanofiltration

KAUST Repository

Pan, Jiangjiang

2011-12-01

Organic micropollutants (OMPs) have received more and more attention in recent years due to their potential harmful effects on public health and aquatic ecosystems, and eliminating OMPs in wastewater treatment systems is an important solution to control OMPs wastage. An innovative hybrid process, anaerobic membrane bioreactor with nanofiltration (AnMBR-NF), in which enhanced OMPs removal is possible based on the concept of compound retention time (CRT) through coupling anaerobic biodegradation and NF rejection, is proposed and examined in terms of preliminary feasibility in this study. First, NF membrane screening through sludge water dead-end filtration tests demonstrated that KOCH NF200 (molecular weight cut-off (MWCO) 200 Da, acid/base stable) performed best in organic matter rejection. Then, selected OMPs (ketobrofen and naproxen) in MQ water and a biologically treated wastewater matrix were filtered through NF200 under constant-pressure dead-end mode, with and without stirring, and several methods (contact angle, scanning electronic microscopy, Zeta potential, Fourier transform infra-red spectroscopy) were used to characterize membranes. Results show selected OMPs in MQ could be rejected (about 40%) by a clean NF200 membrane. The main rejection mechanism was initial absorption by the membrane followed by size exclusion (electric charge interaction plays a less important role). The wastewater matrix could enhance the rejection significantly (up to 90%) because effluent organic matter (EfOM) enhanced size exclusion and electric charge interaction through blocking membrane pores and forming a gel layer as well as binding some OMPs through partitioning followed by retention by NF. Third, an anaerobic bioreactor was set up to evaluate the anaerobic biodegradability of selected OMPs. Results showed selected OMPs could be absorbed by sludge and reached equilibrium within one day, and then were consumed by anaerobic microorganism with a half life 9.4 days for

Urinary retention in women

African Journals Online (AJOL)

Urinary retention in women. Urinary retention in women is often transient and of no known cause. ... stones, constipation, urethral cancer, uterine fibroids ... present with abnormal bladder function secondary to ... (CT), magnetic resonance imaging (MRI) or myelography ... full blood count, urea, electrolytes and creatinine can ...

Amyloid PET imaging in Alzheimer's disease: a comparison of three radiotracers

Energy Technology Data Exchange (ETDEWEB)

Landau, S.M.; Jagust, W.J. [University of California, Berkeley, Helen Wills Neuroscience Institute, Berkeley, CA (United States); Lawrence Berkeley National Laboratory, Life Sciences Division, Berkeley, CA (United States); Thomas, B.A. [University College London, Institute of Nuclear Medicine, London (United Kingdom); Thurfjell, L. [GE Healthcare, Uppsala (Sweden); Schmidt, M. [Janssen Pharmaceutica, NV, Beerse (Belgium); Margolin, R. [Janssen Alzheimer Immunotherapy, South San Francisco, CA (United States); Mintun, M.; Pontecorvo, M. [Avid Radiopharmaceuticals, Inc., Philadelphia, PA (United States); Baker, S.L. [Lawrence Berkeley National Laboratory, Life Sciences Division, Berkeley, CA (United States); Collaboration: The Alzheimer' s Disease Neuroimaging Initiative

2014-07-15

The increasing use of amyloid PET in Alzheimer's disease research and clinical trials has motivated efforts to standardize methodology. We compared retention of the {sup 11}C radiotracer Pittsburgh Compound B (PiB) and that of two {sup 18}F amyloid radiotracers (florbetapir and flutemetamol) using two study populations. We also examined the feasibility of converting between tracer-specific measures, using PiB as the common link between the two {sup 18}F tracers. One group of 40 subjects underwent PiB and flutemetamol imaging sessions and a separate group of 32 subjects underwent PiB and florbetapir imaging sessions. We compared cortical and white matter retention for each {sup 18}F tracer relative to that of PiB, as well as retention in several reference regions and image analysis methods. Correlations between tracer pairs were used to convert tracer-specific threshold values for amyloid positivity between tracers. Cortical retention for each pair of tracers was strongly correlated regardless of reference region (PiB-flutemetamol, ρ = 0.84-0.99; PiB-florbetapir, ρ = 0.83-0.97) and analysis method (ρ = 0.90-0.99). Compared to PiB, flutemetamol had higher white matter retention, while florbetapir had lower cortical retention. Two previously established independent thresholds for amyloid positivity were highly consistent when values were converted between tracer pairs. Despite differing white and grey matter retention characteristics, cortical retention for each {sup 18}F tracer was highly correlated with that of PiB, enabling conversion of thresholds across tracer measurement scales with a high level of internal consistency. Standardization of analysis methods and measurement scales may facilitate the comparison of amyloid PET data obtained using different tracers. (orig.)

Modulation of NADPH oxidase activity by known uraemic retention solutes.

Science.gov (United States)

Schulz, Anna Marta; Terne, Cindy; Jankowski, Vera; Cohen, Gerald; Schaefer, Mandy; Boehringer, Falko; Tepel, Martin; Kunkel, Desiree; Zidek, Walter; Jankowski, Joachim

2014-08-01

Uraemia and cardiovascular disease appear to be associated with an increased oxidative burden. One of the key players in the genesis of reactive oxygen species (ROS) is nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. Based on initial experiments demonstrating a decreased inhibitory effect on NADPH oxidase activity in the presence of plasma from patients with CKD-5D after dialysis compared with before dialysis, we investigated the effect of 48 known and commercially available uraemic retention solutes on the enzymatic activity of NADPH oxidase. Mononuclear leucocytes isolated from buffy coats of healthy volunteers were isolated, lysed and incubated with NADH in the presence of plasma from healthy controls and patients with CKD-5D. Furthermore, the leucocytes were lysed and incubated in the presence of uraemic retention solute of interest and diphenyleneiodonium chloride (DPI), an inhibitor of NADPH oxidase. The effect on enzymatic activity of NADPH oxidase was quantified within an incubation time of 120 min. Thirty-nine of the 48 uraemic retention solutes tested had a significant decreasing effect on NADPH oxidase activity. Oxalate has been characterized as the strongest inhibitor of NADPH oxidase (90% of DPI inhibition). Surprisingly, none of the uraemic retention solutes we investigated was found to increase NADPH oxidase activity. Furthermore, plasma from patients with CKD-5D before dialysis caused significantly higher inhibitory effect on NADPH oxidase activity compared with plasma from healthy subjects. However, this effect was significantly decreased in plasma from patients with CKD-5D after dialysis. The results of this study show that uraemic retention solutes modulated the activity of the NADPH oxidase. The results of this study might be the basis for the development of inhibitors applicable as drug in the situation of increased oxidative stress. © 2014 Stichting European Society for Clinical Investigation Journal Foundation.

White matter involvement in sporadic Creutzfeldt-Jakob disease.

Science.gov (United States)

Caverzasi, Eduardo; Mandelli, Maria Luisa; DeArmond, Stephen J; Hess, Christopher P; Vitali, Paolo; Papinutto, Nico; Oehler, Abby; Miller, Bruce L; Lobach, Irina V; Bastianello, Stefano; Geschwind, Michael D; Henry, Roland G

2014-12-01

Sporadic Creutzfeldt-Jakob disease is considered primarily a disease of grey matter, although the extent of white matter involvement has not been well described. We used diffusion tensor imaging to study the white matter in sporadic Creutzfeldt-Jakob disease compared to healthy control subjects and to correlated magnetic resonance imaging findings with histopathology. Twenty-six patients with sporadic Creutzfeldt-Jakob disease and nine age- and gender-matched healthy control subjects underwent volumetric T1-weighted and diffusion tensor imaging. Six patients had post-mortem brain analysis available for assessment of neuropathological findings associated with prion disease. Parcellation of the subcortical white matter was performed on 3D T1-weighted volumes using Freesurfer. Diffusion tensor imaging maps were calculated and transformed to the 3D-T1 space; the average value for each diffusion metric was calculated in the total white matter and in regional volumes of interest. Tract-based spatial statistics analysis was also performed to investigate the deeper white matter tracts. There was a significant reduction of mean (P=0.002), axial (P=0.0003) and radial (P=0.0134) diffusivities in the total white matter in sporadic Creutzfeldt-Jakob disease. Mean diffusivity was significantly lower in most white matter volumes of interest (PCreutzfeldt-Jakob disease. Mean diffusivity reduction reflected concomitant decrease of both axial and radial diffusivity, without appreciable changes in white matter anisotropy. Tract-based spatial statistics analysis showed significant reductions of mean diffusivity within the white matter of patients with sporadic Creutzfeldt-Jakob disease, mainly in the left hemisphere, with a strong trend (P=0.06) towards reduced mean diffusivity in most of the white matter bilaterally. In contrast, by visual assessment there was no white matter abnormality either on T2-weighted or diffusion-weighted images. Widespread reduction in white matter mean

The Effects of Test Trial and Processing Level on Immediate and Delayed Retention

OpenAIRE

Chang, Sau Hou

2017-01-01

The purpose of the present study was to investigate the effects of test trial and processing level on immediate and delayed retention. A 2 × 2 × 2 mixed ANOVAs was used with two between-subject factors of test trial (single test, repeated test) and processing level (shallow, deep), and one within-subject factor of final recall (immediate, delayed). Seventy-six college students were randomly assigned first to the single test (studied the stimulus words three times and took one free-recall test...

Substance use and regional gray matter volume in individuals at high risk of psychosis.

Science.gov (United States)

Stone, James M; Bhattacharyya, Sagnik; Barker, Gareth J; McGuire, Philip K

2012-02-01

Individuals with an at risk mental state (ARMS) are at greatly increased risk of developing a psychotic illness. Risk of transition to psychosis is associated with regionally reduced cortical gray matter volume. There has been considerable interest in the interaction between psychosis risk and substance use. In this study we investigate the relationship between alcohol, cannabis and nicotine use with gray matter volume in ARMS subjects and healthy volunteers. Twenty seven ARMS subjects and 27 healthy volunteers took part in the study. All subjects underwent volumetric MRI imaging. The relationship between regional gray matter volume and cannabis use, smoking, and alcohol use in controls and ARMS subjects was analysed using voxel-based morphometry. In any region where a significant relationship with drug was present, data were analysed to determine if there was any group difference in this relationship. Alcohol intake was inversely correlated with gray matter volume in cerebellum, cannabis intake was use was inversely correlated with gray matter volume in prefrontal cortex and tobacco intake was inversely correlated with gray matter volume in left temporal cortex. There were no significant interactions by group in any region. There is no evidence to support the hypothesis of increased susceptibility to harmful effects of drugs and alcohol on regional gray matter in ARMS subjects. However, alcohol, tobacco and cannabis at low to moderate intake may be associated with lower gray matter in both ARMS subjects and healthy volunteers-possibly representing low-level cortical damage or change in neural plasticity. Copyright © 2011 Elsevier B.V. All rights reserved.

Features of the Subject Domain of Historical Psychology

OpenAIRE

V A Koltsova

2008-01-01

The known psychologist, the author of a number of important works on methodology of psychological science as a whole and historical psychology, in particular, considers pressing matters of the formation of historical psychology. Her attention is drawn to such matters, as the subject, structure and method of arising intersubject branch of knowledge - historical psychology.

Hiring and Retention: Key Factors in Increasing Gender Diversity in the Geosciences

Science.gov (United States)

Holmes, M.; O'Connell, S.; Frey, C.

2004-12-01

Graduation and hiring data of geoscientists over the last ten years indicate that the largest leak in the academic pipeline for women geoscientists is at hiring into tenure-track positions. Anecdotal explanations for this leak generally cite a lack of females in the applicant pool, but women in tenure-track positions anecdotally cite a lack of family-friendly practices by academic departments. Both ideas are currently being tested via surveys of geoscience departments. Is there a way to attract more women to the field to increase the applicant pool? Results of focus groups of geoscientists indicate that both men and women are attracted into the field of geosciences by the same types of events: over one-third became a geoscientist by randomly walking into an undergraduate class and finding themselves captivated by the topic and/or a dynamic instructor. The subject matter itself attracts another one-fourth, and family members encourage another one-fifth of geoscientists to initially enter the field. Slightly more women cite the first attractor of undergraduate class, but the principal draw for our future workforce, male and female, is good instruction of freshman courses. Retention of women in academia is another key issue. The proportion that considers leaving after working towards one or more degrees is highly skewed by gender: one-half of female and only one-third of male geoscientists considered leaving the field at some time in their career. The reasons for considering leaving also differ by gender. Males cite financial issues, including an uncertain job market. Females cite two principal reasons for considering leaving: family issues and difficulties with a graduate advisor. Strategies currently exist for "family issues", including stop-the-clock (of tenure for family needs), assignment shift, on-campus daycare facilities, and unflinching administrative support for such practices. Graduate advising is a learnable skill, and more attention needs to be paid to

Soil organic matter regulates molybdenum storage and mobility in forests

Science.gov (United States)

Marks, Jade A; Perakis, Steven; King, Elizabeth K.; Pett-Ridge, Julie

2015-01-01

The trace element molybdenum (Mo) is essential to a suite of nitrogen (N) cycling processes in ecosystems, but there is limited information on its distribution within soils and relationship to plant and bedrock pools. We examined soil, bedrock, and plant Mo variation across 24 forests spanning wide soil pH gradients on both basaltic and sedimentary lithologies in the Oregon Coast Range. We found that the oxidizable organic fraction of surface mineral soil accounted for an average of 33 %of bulk soil Mo across all sites, followed by 1.4 % associated with reducible Fe, Al, and Mn-oxides, and 1.4 % in exchangeable ion form. Exchangeable Mo was greatest at low pH, and its positive correlation with soil carbon (C) suggests organic matter as the source of readily exchangeable Mo. Molybdenum accumulation integrated over soil profiles to 1 m depth (τMoNb) increased with soil C, indicating that soil organic matter regulates long-term Mo retention and loss from soil. Foliar Mo concentrations displayed no relationship with bulk soil Mo, and were not correlated with organic horizon Mo or soil extractable Mo, suggesting active plant regulation of Mo uptake and/or poor fidelity of extractable pools to bioavailability. We estimate from precipitation sampling that atmospheric deposition supplies, on average, over 10 times more Mo annually than does litterfall to soil. In contrast, bedrock lithology had negligible effects on foliar and soil Mo concentrations and on Mo distribution among soil fractions. We conclude that atmospheric inputs may be a significant source of Mo to forest ecosystems, and that strong Mo retention by soil organic matter limits ecosystem Mo loss via dissolution and leaching pathways.

Variance in exposed perturbations impairs retention of visuomotor adaptation.

Science.gov (United States)

Canaveral, Cesar Augusto; Danion, Frédéric; Berrigan, Félix; Bernier, Pierre-Michel

2017-11-01

Sensorimotor control requires an accurate estimate of the state of the body. The brain optimizes state estimation by combining sensory signals with predictions of the sensory consequences of motor commands using a forward model. Given that both sensory signals and predictions are uncertain (i.e., noisy), the brain optimally weights the relative reliance on each source of information during adaptation. In support, it is known that uncertainty in the sensory predictions influences the rate and generalization of visuomotor adaptation. We investigated whether uncertainty in the sensory predictions affects the retention of a new visuomotor relationship. This was done by exposing three separate groups to a visuomotor rotation whose mean was common at 15° counterclockwise but whose variance around the mean differed (i.e., SD of 0°, 3.2°, or 4.5°). Retention was assessed by measuring the persistence of the adapted behavior in a no-vision phase. Results revealed that mean reach direction late in adaptation was similar across groups, suggesting it depended mainly on the mean of exposed rotations and was robust to differences in variance. However, retention differed across groups, with higher levels of variance being associated with a more rapid reversion toward nonadapted behavior. A control experiment ruled out the possibility that differences in retention were accounted for by differences in success rates. Exposure to variable rotations may have increased the uncertainty in sensory predictions, making the adapted forward model more labile and susceptible to change or decay. NEW & NOTEWORTHY The brain predicts the sensory consequences of motor commands through a forward model. These predictions are subject to uncertainty. We use visuomotor adaptation and modulate uncertainty in the sensory predictions by manipulating the variance in exposed rotations. Results reveal that variance does not influence the final extent of adaptation but selectively impairs the retention of

The Professional Learning Experiences of Non-Mathematics Subject Specialist Teachers: A Descriptive Study

OpenAIRE

Ho Younghusband, Alice Christine

2017-01-01

Certified teachers in British Columbia (BC) schools can be assigned to teach secondary mathematics without having a major, minor, or formal background in mathematics. This is known as out-of-field teaching. These non-mathematics subject specialist teachers (NMSSTs) must learn or relearn the subject matter of mathematics to teach secondary mathematics. This study investigates what professional learning activities NMSSTs participate in to gain subject matter content knowledge in mathematics, wh...

Reversal of long-term potentiation-like plasticity processes after motor learning disrupts skill retention.

Science.gov (United States)

Cantarero, Gabriela; Lloyd, Ashley; Celnik, Pablo

2013-07-31

Plasticity of synaptic connections in the primary motor cortex (M1) is thought to play an essential role in learning and memory. Human and animal studies have shown that motor learning results in long-term potentiation (LTP)-like plasticity processes, namely potentiation of M1 and a temporary occlusion of additional LTP-like plasticity. Moreover, biochemical processes essential for LTP are also crucial for certain types of motor learning and memory. Thus, it has been speculated that the occlusion of LTP-like plasticity after learning, indicative of how much LTP was used to learn, is essential for retention. Here we provide supporting evidence of it in humans. Induction of LTP-like plasticity can be abolished using a depotentiation protocol (DePo) consisting of brief continuous theta burst stimulation. We used transcranial magnetic stimulation to assess whether application of DePo over M1 after motor learning affected (1) occlusion of LTP-like plasticity and (2) retention of motor skill learning. We found that the magnitude of motor memory retention is proportional to the magnitude of occlusion of LTP-like plasticity. Moreover, DePo stimulation over M1, but not over a control site, reversed the occlusion of LTP-like plasticity induced by motor learning and disrupted skill retention relative to control subjects. Altogether, these results provide evidence of a link between occlusion of LTP-like plasticity and retention and that this measure could be used as a biomarker to predict retention. Importantly, attempts to reverse the occlusion of LTP-like plasticity after motor learning comes with the cost of reducing retention of motor learning.

Gray Matter Concentration Abnormality in Brains of Narcolepsy Patients

Energy Technology Data Exchange (ETDEWEB)

Joo, Eun Yeon; Tae, Woo Suk; Kim, Sung Tae; Hong, Seung Bong [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

2009-12-15

To investigate gray matter concentration changes in the brains of narcoleptic patients. Twenty-nine narcoleptic patient with cataplexy and 29 age and sex-matched normal subjects (mean age, 31 years old) underwent volumetric MRIs. The MRIs were spatially normalized to a standard T1 template and subdivided into gray matter, white matter, and cerebrospinal fluid (CSF). These segmented images were then smoothed using a 12-mm full width at half maximum (FWHM) isotropic Gaussian kernel. An optimized voxel-based morphometry protocol was used to analyze brain tissue concentrations using SPM2 (statistical parametric mapping). A one-way analysis of variance was applied to the concentration analysis of gray matter images. Narcoleptics with cataplexy showed reduced gray matter concentration in bilateral thalami, left gyrus rectus, bilateral frontopolar gyri, bilateral short insular gyri, bilateral superior frontal gyri, and right superior temporal and left inferior temporal gyri compared to normal subjects (uncorrected p < 0.001). Furthermore, small volume correction revealed gray matter concentration reduction in bilateral nuclei accumbens, hypothalami, and thalami (false discovery rate corrected p < 0.05). Gray matter concentration reductions were observed in brain regions related to excessive daytime sleepiness, cognition, attention, and memory in narcoleptics with cataplexy

Gray Matter Concentration Abnormality in Brains of Narcolepsy Patients

International Nuclear Information System (INIS)

Joo, Eun Yeon; Tae, Woo Suk; Kim, Sung Tae; Hong, Seung Bong

2009-01-01

To investigate gray matter concentration changes in the brains of narcoleptic patients. Twenty-nine narcoleptic patient with cataplexy and 29 age and sex-matched normal subjects (mean age, 31 years old) underwent volumetric MRIs. The MRIs were spatially normalized to a standard T1 template and subdivided into gray matter, white matter, and cerebrospinal fluid (CSF). These segmented images were then smoothed using a 12-mm full width at half maximum (FWHM) isotropic Gaussian kernel. An optimized voxel-based morphometry protocol was used to analyze brain tissue concentrations using SPM2 (statistical parametric mapping). A one-way analysis of variance was applied to the concentration analysis of gray matter images. Narcoleptics with cataplexy showed reduced gray matter concentration in bilateral thalami, left gyrus rectus, bilateral frontopolar gyri, bilateral short insular gyri, bilateral superior frontal gyri, and right superior temporal and left inferior temporal gyri compared to normal subjects (uncorrected p < 0.001). Furthermore, small volume correction revealed gray matter concentration reduction in bilateral nuclei accumbens, hypothalami, and thalami (false discovery rate corrected p < 0.05). Gray matter concentration reductions were observed in brain regions related to excessive daytime sleepiness, cognition, attention, and memory in narcoleptics with cataplexy

76 FR 24089 - Credit Risk Retention

Science.gov (United States)

2011-04-29

... 17 CFR Part 246 Department of Housing and Urban Development 24 CFR Part 267 Credit Risk Retention... 2501-AD53 Credit Risk Retention AGENCIES: Office of the Comptroller of the Currency, Treasury (OCC..., Commission, FHFA, and HUD (the Agencies) are proposing rules to implement the credit risk retention...

The human body retention time of environmental organically bound tritium

Energy Technology Data Exchange (ETDEWEB)

Hunt, John; Bailey, Trevor [Centre for Environment, Fisheries and Aquaculture Science, Pakefield Road, Lowestoft, Suffolk NR33 0HT (United Kingdom); Reese, Allan [Centre for Environment, Fisheries and Aquaculture Science, The Nothe, Barrack Road, Weymouth, Dorset DT4 8UB (United Kingdom)], E-mail: john.hunt@cefas.co.uk

2009-03-15

Tritium in the UK environment causes low radiation doses to the public, but uncertainty exists in the dose coefficient for the organically bound component of tritium (OBT). This can affect the assessment of effective doses to representative persons. Contributing to that uncertainty is poor knowledge of the body retention time of OBT and how this varies for different OBT compounds in food. This study was undertaken to measure the retention time of tritium by volunteers after eating sole from Cardiff Bay, which may contain OBT from discharges from the GE Healthcare Ltd plant. Five volunteers provided samples of excreta over periods up to 150 days after intake. The results, which are presented in raw form to allow independent analysis, suggest retention of total tritium with body half-times ranging from 4 to 11 days, with no evidence (subject to experimental noise) of a significant contribution due to retention with a longer half-time. This range covers the half-time of 10 days used by the ICRP for tritiated water. The short timescale could be due to rapid hydrolysis in body tissues of the particular form of OBT used in this study. Implications for the dose coefficient for OBT are that the use of the ICRP value of 4.2 x 10{sup -11} Sv Bq{sup -1} may be cautious in this specific situation. These observations on dose coefficients are separate from any implications of recent discussion on whether the tritium radiation weighting factor should be increased from 1 to 2.

Retention capacity of correlated surfaces.

Science.gov (United States)

Schrenk, K J; Araújo, N A M; Ziff, R M; Herrmann, H J

2014-06-01

We extend the water retention model [C. L. Knecht et al., Phys. Rev. Lett. 108, 045703 (2012)] to correlated random surfaces. We find that the retention capacity of discrete random landscapes is strongly affected by spatial correlations among the heights. This phenomenon is related to the emergence of power-law scaling in the lake volume distribution. We also solve the uncorrelated case exactly for a small lattice and present bounds on the retention of uncorrelated landscapes.

Retention capacity of correlated surfaces

OpenAIRE

Schrenk, K. J.; Araújo, N. A. M.; Ziff, R. M.; Herrmann, H. J.

2014-01-01

We extend the water retention model [C. L. Knecht et al., Phys. Rev. Lett. 108, 045703 (2012)] to correlated random surfaces. We find that the retention capacity of discrete random landscapes is strongly affected by spatial correlations among the heights. This phenomenon is related to the emergence of power-law scaling in the lake volume distribution. We also solve the uncorrelated case exactly for a small lattice and present bounds on the retention of uncorrelated landscapes.

Improving retention and motivation in non-clinical dialysis employees.

Science.gov (United States)

Campbell, Anne

2004-02-01

For no additional expense, little intrusion into the schedule or duties of the day, and no additional personnel to hire, dialysis facilities can make a dramatic impact on the training, motivation, and retention of employees through the use of classes designed specifically for the needs of newly employed non-clinical personnel. In today's world where many are expected to do a task with little or no orientation to the overall values and goals of the organization and how their tasks matter, what other action can accomplish so much for employee motivation and retention for so little time and expense? At DCI Mid-Missouri this program has been successful in retaining many excellent employees over many years and has been part of an ongoing effort to increase employees' interest and commitment to their work and the organization. It has also made them much more aware of treatments, other personnel and most of all, of our patients and their needs. It fulfills the needs of humans to be valued and have meaningful work. It contains costs and helps efficiency and productivity. Most of all, it keeps excellent people on the job and enjoying their work more than they would have. Participants' words when evaluating the most recent series of classes speak for themselves in demonstrating these important benefits that can be achieved easily in dialysis facilities throughout the United States and the world.

77 FR 269 - Matters Related to Patent Appeals

Science.gov (United States)

2012-01-04

... DEPARTMENT OF COMMERCE United States Patent and Trademark Office Matters Related to Patent Appeals ACTION: Proposed collection; comment request. SUMMARY: The United States Patent and Trademark Office... Matters Related to Patent Appeals comment'' in the subject line of the message. Mail: Susan K. Fawcett...

Encoding vs. retention: differential effects of cue manipulation on working memory performance in schizophrenia.

Science.gov (United States)

Javitt, Daniel C; Rabinowicz, Esther; Silipo, Gail; Dias, Elisa C

2007-03-01

Deficits in working memory performance are among the most widely replicated findings in schizophrenia. Roles of encoding vs. memory retention in working memory remain unresolved. The present study evaluated working memory performance in schizophrenia using an AX-type continuous performance test (AX-CPT) paradigm. Participants included 48 subjects with schizophrenia and 27 comparison subjects. Behavior was obtained in 3 versions of the task, which differed based upon ease of cue interoperability. In a simple cue version of the task, cue letters were replaced with red or green circles. In the complex cue version, letter/color conjunctions served as cues. In the base version of the task, patients showed increased rates of false alarms to invalidly cued targets, similar to prior reports. However, when the cue stimuli were replaced with green or red circles to ease interpretation, patients showed similar false alarm rates to controls. When feature conjunction cues were used, patients were also disproportionately affected relative to controls. No significant group by interstimulus interval interaction effects were observed in either the simple or complex cue conditions, suggesting normal retention of information even in the presence of overall performance decrements. These findings suggest first, that cue manipulation disproportionately affects AX-CPT performance in schizophrenia and, second, that substantial behavioral deficits may be observed on working memory tasks even in the absence of disturbances in mnemonic retention.

Estimation of the contribution of gaps to tritium retention in the divertor of ITER

Czech Academy of Sciences Publication Activity Database

Matveev, D.; Kirschner, A.; Schmid, K.; Litnovsky, A.; Borodin, D.; Komm, Michael; Van Oost, G.; Samm, U.

-, T159 (2014), 014063-014063 ISSN 0031-8949 Institutional support: RVO:61389021 Keywords : plasma * tokamak * tritium retention * ITER * castellated surfaces * gaps * divertor * impurity deposition Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.126, year: 2014 http://iopscience.iop.org/1402-4896/2014/T159/014063/

Supervising and Controlling Unmanned Systems: A Multi-Phase Study with Subject Matter Experts.

Science.gov (United States)

Porat, Talya; Oron-Gilad, Tal; Rottem-Hovev, Michal; Silbiger, Jacob

2016-01-01

Proliferation in the use of Unmanned Aerial Systems (UASs) in civil and military operations has presented a multitude of human factors challenges; from how to bridge the gap between demand and availability of trained operators, to how to organize and present data in meaningful ways. Utilizing the Design Research Methodology (DRM), a series of closely related studies with subject matter experts (SMEs) demonstrate how the focus of research gradually shifted from "how many systems can a single operator control" to "how to distribute missions among operators and systems in an efficient way". The first set of studies aimed to explore the modal number, i.e., how many systems can a single operator supervise and control. It was found that an experienced operator can supervise up to 15 UASs efficiently using moderate levels of automation, and control (mission and payload management) up to three systems. Once this limit was reached, a single operator's performance was compared to a team controlling the same number of systems. In general, teams led to better performances. Hence, shifting design efforts toward developing tools that support teamwork environments of multiple operators with multiple UASs (MOMU). In MOMU settings, when the tasks are similar or when areas of interest overlap, one operator seems to have an advantage over a team who needs to collaborate and coordinate. However, in all other cases, a team was advantageous over a single operator. Other findings and implications, as well as future directions for research are discussed.

Gastro-retentive drug delivery systems and their in vivo success: A recent update

Directory of Open Access Journals (Sweden)

Uttam Kumar Mandal

2016-10-01

Full Text Available Gastro-retentive drug delivery system (GRDDS has gained immense popularity in the field of oral drug delivery recently. It is a widely employed approach to retain the dosage form in the stomach for an extended period of time and release the drug slowly that can address many challenges associated with conventional oral delivery, including poor bioavailability. Different innovative approaches like magnetic field assisted gastro-retention, plug type swelling system, muco-adhesion technique, floating system with or without effervescence are being applied to fabricate GRDDS. Apart from in vitro characterization, successful GRDDS development demands well designed in vivo study to establish enhanced gastro-retention and prolonged drug release. Gama scintigraphy and MRI are popular techniques to evaluate in vivo gastric residence time. However, checking of their overall in-vivo efficacy still remains a major challenge for this kind of dosage form, especially in small animals like mice or rat. Reported in vivo studies with beagle dogs, rabbits, and human subjects are only a handful in spite of a large number of encouraging in vitro results. In spite of the many advantages, high subject variations in gastrointestinal physiological condition, effect of food, and variable rate of gastric emptying time are the challenges that limit the number of available GRDDS in the market. This review article highlights the in vivo works of GRDDS carried out in the recent past, including their limitations and challenges that need to be overcome in the near future.

Make dark matter charged again

Energy Technology Data Exchange (ETDEWEB)

Agrawal, Prateek; Cyr-Racine, Francis-Yan; Randall, Lisa; Scholtz, Jakub, E-mail: prateekagrawal@fas.harvard.edu, E-mail: fcyrraci@physics.harvard.edu, E-mail: randall@physics.harvard.edu, E-mail: jscholtz@physics.harvard.edu [Department of Physics, Harvard University, Cambridge, MA 02138 (United States)

2017-05-01

We revisit constraints on dark matter that is charged under a U(1) gauge group in the dark sector, decoupled from Standard Model forces. We find that the strongest constraints in the literature are subject to a number of mitigating factors. For instance, the naive dark matter thermalization timescale in halos is corrected by saturation effects that slow down isotropization for modest ellipticities. The weakened bounds uncover interesting parameter space, making models with weak-scale charged dark matter viable, even with electromagnetic strength interaction. This also leads to the intriguing possibility that dark matter self-interactions within small dwarf galaxies are extremely large, a relatively unexplored regime in current simulations. Such strong interactions suppress heat transfer over scales larger than the dark matter mean free path, inducing a dynamical cutoff length scale above which the system appears to have only feeble interactions. These effects must be taken into account to assess the viability of darkly-charged dark matter. Future analyses and measurements should probe a promising region of parameter space for this model.

Prediction of the soil water retention curve for structured soil from saturation to oven-dryness

DEFF Research Database (Denmark)

Karup, Dan; Møldrup, Per; Tuller, Markus

2017-01-01

. Independently measured SWRCs for 171 undisturbed soil samples with organic matter contents that ranged from 3 to 14% were used for model validation. The results indicate that consideration of the silt and organic matter fractions, in addition to the clay fraction, improved predictions for the dry-end SWRC......The soil water retention curve (SWRC) is the most fundamental soil hydraulic function required for modelling soil–plant–atmospheric water flow and transport processes. The SWRC is intimately linked to the distribution of the size of pores, the composition of the solid phase and the soil specific...... surface area. Detailed measurement of the SWRC is impractical in many cases because of the excessively long equilibration times inherent to most standard methods, especially for fine textured soil. Consequently, it is more efficient to predict the SWRCbased on easy-to-measure basic soil properties...

Cigarette smoking is associated with reduced microstructural integrity of cerebral white matter.

Science.gov (United States)

Gons, Rob A R; van Norden, Anouk G W; de Laat, Karlijn F; van Oudheusden, Lucas J B; van Uden, Inge W M; Zwiers, Marcel P; Norris, David G; de Leeuw, Frank-Erik

2011-07-01

Cigarette smoking doubles the risk of dementia and Alzheimer's disease. Various pathophysiological pathways have been proposed to cause such a cognitive decline, but the exact mechanisms remain unclear. Smoking may affect the microstructural integrity of cerebral white matter. Diffusion tensor imaging is known to be sensitive for microstructural changes in cerebral white matter. We therefore cross-sectionally studied the relation between smoking behaviour (never, former, current) and diffusion tensor imaging parameters in both normal-appearing white matter and white matter lesions as well as the relation between smoking behaviour and cognitive performance. A structured questionnaire was used to ascertain the amount and duration of smoking in 503 subjects with small-vessel disease, aged between 50 and 85 years. Cognitive function was assessed with a neuropsychological test battery. All subjects underwent 1.5 Tesla magnetic resonance imaging. Using diffusion tensor imaging, fractional anisotropy and mean diffusivity were calculated in both normal-appearing white matter and white matter lesions. A history of smoking was associated with significant higher values of mean diffusivity in normal-appearing white matter and white matter lesions (P-trend for smoking status = 0.02) and with poorer cognitive functioning compared with those who never smoked. Associations with smoking and loss of structural integrity appeared to be strongest in normal-appearing white matter. Furthermore, the duration of smoking cessation was positively related to lower values of mean diffusivity and higher values of fractional anisotropy in normal-appearing white matter [β = -0.004 (95% confidence interval -0.007 to 0.000; P = 0.03) and β = 0.019 (95% confidence interval 0.001-0.038; P = 0.04)]. Fractional anisotropy and mean diffusivity values in normal-appearing white matter of subjects who had quit smoking for >20 years were comparable with subjects who had never smoked. These data suggest

Uncovering client retention antecedents in service organizations

Directory of Open Access Journals (Sweden)

Mari Jansen van Rensburg

2014-01-01

Full Text Available This paper develops a multi-dimensional model of retention to provide a more complete and integrated view of client retention and its determinants in service contexts. To uncover the antecedents of client retention, social and economic exchanges were reviewed under the fundamental ideas of the Social Exchange Theory. Findings from a survey of senior South African advertising executives suggest that client retention is the result of evaluative as well as relational factors that can influence client responses. Despite contractual obligations, advertisers are willing to pay the costs and make the sacrifices of switching should their expectations be unmet. An important contribution of this study is the use of multi-item scales to measure retention. The model developed provides valuable insight to agencies on client retention management and the optimal allocation of resources for maximum customer equity. This model may also be applied to other service organisations to provide insight to client retention.

A Comparison of Colour and Black and White T. V.

Science.gov (United States)

Reich, Carol; Meisner, Alan

The relative educational effectiveness of color vs. black and white television has not been exhaustively explored. While previous studies have concentrated on the factual retention of subject matter--bypassing the subjective attitudes--this study was designed to thoroughly analyze both areas. Using Osgood's Semantic Differential and the Liking…

Retention of Emergency Care Knowledge.

Science.gov (United States)

Burckes, Mardie E.; Shao, Kung Ping Pam

1984-01-01

Data on the emergency care knowledge of college students were measured by a pretest, posttest, and retention test. A high relationship was found between students' posttest scores and retention test scores. Findings are discussed. (Author/DF)

Effects of calcium carbonate and hydroxyapatite on zinc and iron retention in postmenopausal women

International Nuclear Information System (INIS)

Dawson-Hughes, B.; Seligson, F.H.; Hughes, V.A.

1986-01-01

We measured the effect of calcium carbonate and hydroxyapatite on whole-body retention of zinc-65 in 11 and iron-59 in 13 healthy, postmenopausal women. In a single-blind, controlled, crossover study, each subject, on three occasions, ingested a standard test meal supplemented with iron-59 or zinc-65 and capsules containing placebo or 500 mg elemental calcium as calcium carbonate or hydroxyapatite. Whole-body countings were performed prior to, 30 min after, and 2 wk after each meal. Mean (SEM) zinc retention was 18.1 +/- 1.0% with placebo (control) and did not vary significantly with calcium carbonate (110.0 +/- 8.6% of control) or hydroxyapatite (106.0 +/- 7.9% of control). Iron retention, 6.3 +/- 2.0% with placebo, was significantly reduced with both calcium carbonate (43.3 +/- 8.8% of control, p = 0.002) and hydroxyapatite (45.9 +/- 10.0% of control, p = 0.003). Iron absorption may be significantly reduced when calcium supplements are taken with meals

The influence of career orientations on subjective work experiences

Directory of Open Access Journals (Sweden)

Melinde Coetzee

2010-11-01

Research purpose: The study empirically assessed the causal influence of individuals’ career orientations on their perceived life satisfaction, job or career satisfaction, sense of happiness and their perceptions of work as a valuable activity as aspects of their subjective work experiences. Motivation for study: From an organisational perspective, research on individuals’ inner definitions of career success and satisfaction is needed to guide current selection, placement, development, reward and retention practices. Research design, approach and method: A quantitative survey was conducted on a random sample of 2997 participants at predominantly managerial and supervisory level in the service industry. The measuring instruments consisted of an adapted five-factor career orientations model of the Career Orientations Inventory and a 4-item global subjective work experiences scale. Structural equation modelling (SEM was conducted to achieve the aim of the study. Main findings/results: Statistically significant causal relationships were observed between the career orientations and subjective work experiences variables. Practical implications: Individuals’ career orientations influence their general sense of life and job or career satisfaction, happiness and perceptions of work as a valuable activity. Organisations concerned with the retention of staff need to find a way of aligning individuals’ career needs and motives with the goals and aspirations of the organisation. Contribution/value-add: The research confirms the need for assessing the inner career orientations of employees as these provide valuable information regarding the motives and values driving individuals’ career decision making and subjective experiences of their working lives.

The pursuit of dark matter at colliders—an overview

Science.gov (United States)

Penning, Björn

2018-06-01

Dark matter is one of the main puzzles in fundamental physics and the goal of a diverse, multi-pronged research programme. Underground and astrophysical searches look for dark matter particles in the cosmos, either by interacting directly or by searching for dark matter annihilation. Particle colliders, in contrast, might produce dark matter in the laboratory and are able to probe most basic dark-matter–matter interactions. They are sensitive to low dark matter masses, provide complementary information at higher masses and are subject to different systematic uncertainties. Collider searches are therefore an important part of an inter-disciplinary dark matter search strategy. This article highlights the experimental and phenomenological development in collider dark matter searches of recent years and their connection with the wider field.

14 CFR 17.11 - Matters not subject to protest.

Science.gov (United States)

2010-01-01

... Acquisition: (a) FAA purchases from or through, state, local, and tribal governments and public authorities...) Other transactions which do not fall into the category of procurement contracts subject to the AMS. ...

Human subjects and experimental irradiation

International Nuclear Information System (INIS)

Rosen, R.

1985-01-01

In recent years the public has expressed concern about the use of human subjects in scientific research. Some professional institutions have adopted codes of practice to guide them in this matter. At the University of New South Wales, where human subjects are used in teaching and research programmes, a committee ensures that high ethical standards are maintained. As the volunteer subjects do not gain any benefit themselves from the procedures, their level of risk is kept low. One type of procedure in which risk is becoming quantifiable, is the irradiation of human subjects. To assist peer review groups, the ICRP, WHO and the National Health and Medical Research Council have enunciated principles which should be followed in the irradiation of human volunteer subjects. In general the role of the Committee is advisory to protect the rights of the investigator, the subject, and the institution. Some of the inherent problems are discussed

Multivariate analysis of chromatographic retention data as a supplementary means for grouping structurally related compounds.

Science.gov (United States)

Fasoula, S; Zisi, Ch; Sampsonidis, I; Virgiliou, Ch; Theodoridis, G; Gika, H; Nikitas, P; Pappa-Louisi, A

2015-03-27

In the present study a series of 45 metabolite standards belonging to four chemically similar metabolite classes (sugars, amino acids, nucleosides and nucleobases, and amines) was subjected to LC analysis on three HILIC columns under 21 different gradient conditions with the aim to explore whether the retention properties of these analytes are determined from the chemical group they belong. Two multivariate techniques, principal component analysis (PCA) and discriminant analysis (DA), were used for statistical evaluation of the chromatographic data and extraction similarities between chemically related compounds. The total variance explained by the first two principal components of PCA was found to be about 98%, whereas both statistical analyses indicated that all analytes are successfully grouped in four clusters of chemical structure based on the retention obtained in four or at least three chromatographic runs, which, however should be performed on two different HILIC columns. Moreover, leave-one-out cross-validation of the above retention data set showed that the chemical group in which an analyte belongs can be 95.6% correctly predicted when the analyte is subjected to LC analysis under the same four or three experimental conditions as the all set of analytes was run beforehand. That, in turn, may assist with disambiguation of analyte identification in complex biological extracts. Copyright © 2015 Elsevier B.V. All rights reserved.

On the optimal design of risk retention in securitisation

Directory of Open Access Journals (Sweden)

Metin Kaptan

2011-09-01

Full Text Available This paper examines the optimal design of retention in securitisation, in order to maximize welfare of screening per unit of retention, assuming that screening is costly and that the bank intends to securitise its loans. In contrast to the focus of previous literature on tranche retention, we deviate from the constitutional mechanisms of tranche retention to present a pareto-optimal method of tranche retention. Unlike the current ad-hoc-regulations, we derive the optimal design of retention from a utility maximization problem. We show that the level of retention per tranche should be dependent on the rate of credit default, i.e. the higher the rate of default, the higher the optimal rate of retention required to provide an incentive to screen carefully. From this approach, it follows that the rate of retention per tranche should be higher, the higher the position within the ranking order of subordination. Accordingly, the efficiency of tranche retention can be enhanced, reducing the level of retention required to maintain a given level of screening-effort. This retention design entails a recovery of the bank’s equity capital, thereby increasing liquidity and lending capacities.

The influence of discovery learning model application to the higher order thinking skills student of Srijaya Negara Senior High School Palembang on the animal kingdom subject matter

Science.gov (United States)

Riandari, F.; Susanti, R.; Suratmi

2018-05-01

This study aimed to find out the information in concerning the influence of discovery learning model application to the higher order thinking skills at the tenth grade students of Srijaya Negara senior high school Palembang on the animal kingdom subject matter. The research method used was pre-experimental with one-group pretest-posttest design. The researchconducted at Srijaya Negara senior high school Palembang academic year 2016/2017. The population sample of this research was tenth grade students of natural science 2. Purposive sampling techniquewas applied in this research. Data was collected by(1) the written test, consist of pretest to determine the initial ability and posttest to determine higher order thinking skills of students after learning by using discovery learning models. (2) Questionnaire sheet, aimed to investigate the response of the students during the learning process by using discovery learning models. The t-test result indicated there was significant increasement of higher order thinking skills students. Thus, it can be concluded that the application of discovery learning modelhad a significant effect and increased to higher order thinking skills students of Srijaya Negara senior high school Palembang on the animal kingdom subject matter.

Supervising and Controlling Unmanned Systems: A Multi-Phase Study with Subject Matter Experts

Science.gov (United States)

Porat, Talya; Oron-Gilad, Tal; Rottem-Hovev, Michal; Silbiger, Jacob

2016-01-01

Proliferation in the use of Unmanned Aerial Systems (UASs) in civil and military operations has presented a multitude of human factors challenges; from how to bridge the gap between demand and availability of trained operators, to how to organize and present data in meaningful ways. Utilizing the Design Research Methodology (DRM), a series of closely related studies with subject matter experts (SMEs) demonstrate how the focus of research gradually shifted from “how many systems can a single operator control” to “how to distribute missions among operators and systems in an efficient way”. The first set of studies aimed to explore the modal number, i.e., how many systems can a single operator supervise and control. It was found that an experienced operator can supervise up to 15 UASs efficiently using moderate levels of automation, and control (mission and payload management) up to three systems. Once this limit was reached, a single operator's performance was compared to a team controlling the same number of systems. In general, teams led to better performances. Hence, shifting design efforts toward developing tools that support teamwork environments of multiple operators with multiple UASs (MOMU). In MOMU settings, when the tasks are similar or when areas of interest overlap, one operator seems to have an advantage over a team who needs to collaborate and coordinate. However, in all other cases, a team was advantageous over a single operator. Other findings and implications, as well as future directions for research are discussed. PMID:27252662

Interaction of radiation with matter

CERN Document Server

Nikjoo, Hooshang; Emfietzoglou, Dimitris

2012-01-01

Written for students approaching the subject for the first time, this text provides a solid grounding in the physics of the interactions of photons and particles with matter, which is the basis of radiological physics and radiation dosimetry. The authors first present the relevant atomic physics and then describe the interactions, emphasizing practical applications in health/medical physics and radiation biology. They cover such important topics as microdosimetry, interaction of photons with matter, electron energy loss, and dielectric response. Each chapter includes exercises and a summary.

Retention and recruitment of general dentists in an adjunct teaching model-A pilot study.

Directory of Open Access Journals (Sweden)

Brian J Howe

Full Text Available Retention and recruitment of part time clinical adjunct faculty members in dental education is becoming increasingly difficult as dental schools come to rely on this workforce for their increased involvement in clinical education. Contributing factors include full time faculty shortage, aging workforce, practice and student debt, practice and family commitments, and financial compensation. This study attempts to ascertain barriers to teaching so appropriate strategies can be formulated to address this issue.In the spring of 2016 an email survey was sent to current and former adjunct faculty members to ascertain demographics and retention and recruitment strategies. Descriptive analyses were completed for all variables in the sample.Twenty nine of forty six subjects responded to the survey with a response rate of 63%. Subjects over the age of sixty comprised 55% with only 17% being under the age of forty five. Overall family and practice commitments along with compensation were the primary barriers to teaching part time. For new dentists, student loan debt was the primary barrier to teaching. Travel to teach was also a barrier as 70% of respondents drove 200 miles or less to the dental school.The study demonstrated that the aging part time work force is a great concern and new part time clinical adjunct faculty members must be recruited. Barriers to recruitment and retention of faculty must be considered and addressed to sustain this teaching model.

Limbic grey matter changes in early Parkinson's disease.

Science.gov (United States)

Li, Xingfeng; Xing, Yue; Schwarz, Stefan T; Auer, Dorothee P

2017-05-02

The purpose of this study was to investigate local and network-related changes of limbic grey matter in early Parkinson's disease (PD) and their inter-relation with non-motor symptom severity. We applied voxel-based morphometric methods in 538 T1 MRI images retrieved from the Parkinson's Progression Markers Initiative website. Grey matter densities and cross-sectional estimates of age-related grey matter change were compared between subjects with early PD (n = 366) and age-matched healthy controls (n = 172) within a regression model, and associations of grey matter density with symptoms were investigated. Structural brain networks were obtained using covariance analysis seeded in regions showing grey matter abnormalities in PD subject group. Patients displayed focally reduced grey matter density in the right amygdala, which was present from the earliest stages of the disease without further advance in mild-moderate disease stages. Right amygdala grey matter density showed negative correlation with autonomic dysfunction and positive with cognitive performance in patients, but no significant interrelations were found with anxiety scores. Patients with PD also demonstrated right amygdala structural disconnection with less structural connectivity of the right amygdala with the cerebellum and thalamus but increased covariance with bilateral temporal cortices compared with controls. Age-related grey matter change was also increased in PD preferentially in the limbic system. In conclusion, detailed brain morphometry in a large group of early PD highlights predominant limbic grey matter deficits with stronger age associations compared with controls and associated altered structural connectivity pattern. This provides in vivo evidence for early limbic grey matter pathology and structural network changes that may reflect extranigral disease spread in PD. Hum Brain Mapp, 2017. © 2017 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc. © 2017 The

Data Retention and Anonymity Services

Science.gov (United States)

Berthold, Stefan; Böhme, Rainer; Köpsell, Stefan

The recently introduced legislation on data retention to aid prosecuting cyber-related crime in Europe also affects the achievable security of systems for anonymous communication on the Internet. We argue that data retention requires a review of existing security evaluations against a new class of realistic adversary models. In particular, we present theoretical results and first empirical evidence for intersection attacks by law enforcement authorities. The reference architecture for our study is the anonymity service AN.ON, from which we also collect empirical data. Our adversary model reflects an interpretation of the current implementation of the EC Directive on Data Retention in Germany.

Acute urinary retention in a 23-year-old woman with mild encephalopathy with a reversible splenial lesion: a case report

Directory of Open Access Journals (Sweden)

Isobe Hideyuki

2011-04-01

Full Text Available Abstract Introduction Patients with clinically mild encephalitis/encephalopathy with a reversible splenial lesion present with relatively mild central nervous system disturbances. Although the exact etiology of the condition remains poorly understood, it is thought to be associated with infective agents. We present a case of a patient with mild encephalitis/encephalopathy with a reversible splenial lesion, who had the unusual feature of acute urinary retention. Case presentation A 23-year-old Japanese woman developed mild confusion, gait ataxia, and urinary retention seven days after onset of fever and headache. Magnetic resonance imaging demonstrated T2 prolongation in the splenium of the corpus callosum and bilateral cerebral white matter. These magnetic resonance imaging abnormalities disappeared two weeks later, and all of the symptoms resolved completely within four weeks. Except for the presence of acute urinary retention (due to underactive detrusor without hyper-reflexia, the clinical and radiologic features of our patient were consistent with those of previously reported patients with mild encephalitis/encephalopathy with a reversible splenial lesion. To the best of our knowledge, this is the first report of acute urinary retention recognized in a patient with mild encephalitis/encephalopathy with a reversible splenial lesion. Conclusion Our findings suggest that mild encephalitis/encephalopathy with a reversible splenial lesion can be associated with impaired bladder function and indicate that acute urinary retention in this benign disorder should be treated immediately to avoid bladder injury.

Best practices in doctoral retention: Mentoring

Directory of Open Access Journals (Sweden)

Judie L. Brill

2014-06-01

Full Text Available  The aim of this critical literature review is to outline best practices in doctoral retention and the successful approach of one university to improve graduation success by providing effective mentorship for faculty and students alike. The focus of this literature review is on distance learning relationships between faculty and doctoral students, regarding retention, persistence, and mentoring models. Key phrases and words used in the search and focusing on mentoring resulted in over 20,000 sources. The search was narrowed to include only doctoral study and mentoring. Research questions of interest were: Why do high attrition rates exist for doctoral students? What are the barriers to retention? What are the benefits of doctoral mentoring? What programs do institutions have in place to reduce attrition? The researchers found a key factor influencing doctoral student retention and success is effective faculty mentorship. In particular, the design of a mentoring and faculty training program to increase retention and provide for success after graduation is important. This research represents a key area of interest in the retention literature, as institutions continue to search for ways to better support students during their doctoral programs and post-graduation. DOI: 10.18870/hlrc.v4i2.186

White matter hyperintensities and changes in white matter integrity in patients with Alzheimer's disease

International Nuclear Information System (INIS)

Wang, Liya; Mao, Hui; Goldstein, Felicia C.; Levey, Allan I.; Lah, James J.; Meltzer, Carolyn C.; Holder, Chad A.

2011-01-01

White matter hyperintensities (WMHs) are a risk factor for Alzheimer's disease (AD). This study investigated the relationship between WMHs and white matter changes in AD using diffusion tensor imaging (DTI) and the sensitivity of each DTI index in distinguishing AD with WMHs. Forty-four subjects with WMHs were included. Subjects were classified into three groups based on the Scheltens rating scale: 15 AD patients with mild WMHs, 12 AD patients with severe WMHs, and 17 controls with mild WMHs. Fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (D R ), and axial diffusivity (D A ) were analyzed using the region of interest and tract-based spatial statistics methods. Sensitivity and specificity of DTI indices in distinguishing AD groups from the controls were evaluated. AD patients with mild WMHs exhibited differences from control subjects in most DTI indices in the medial temporal and frontal areas; however, differences in DTI indices from AD patients with mild WMHs and AD patients with severe WMHs were found in the parietal and occipital areas. FA and D R were more sensitive measurements than MD and D A in differentiating AD patients from controls, while MD was a more sensitive measurement in distinguishing AD patients with severe WMHs from those with mild WMHs. WMHs may contribute to the white matter changes in AD brains, specifically in temporal and frontal areas. Changes in parietal and occipital lobes may be related to the severity of WMHs. D R may serve as an imaging marker of myelin deficits associated with AD. (orig.)

Long-term retention of a divided attention psycho-motor test combining choice reaction test and postural balance test: A preliminary study.

Science.gov (United States)

Rossi, R; Pascolo, P B

2015-09-01

Driving in degraded psychophysical conditions, such as under the influence of alcohol or drugs but also in a state of fatigue or drowsiness, is a growing problem. The current roadside tests used for detecting drugs from drivers suffer various limitations, while impairment is subjective and does not necessarily correlate with drug metabolite concentration found in body fluids. This work is a validation step towards the study of feasibility of a novel test conceived to assess psychophysical conditions of individuals performing at-risk activities. Motor gestures, long-term retention and learning phase related to the protocol are analysed in unimpaired subjects. The protocol is a divided attention test, which combines a critical tracking test achieved with postural movements and a visual choice reaction test. Ten healthy subjects participated in a first set of trials and in a second set after about six months. Each session required the carrying out of the test for ten times in order to investigate learning effect and performance over repetitions. In the first set the subjects showed a learning trend up to the third trial, whilst in the second set of trials they showed motor retention. Nevertheless, the overall performance did not significantly improve. Gestures are probably retained due to the type of tasks and the way in which the instructions are conveyed to the subjects. Moreover, motor retention after a short training suggests that the protocol is easy to learn and understand. Implications for roadside test usage and comparison with current tests are also discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.

A Study on Employee Retention Techniques

OpenAIRE

Savarimuthu, Dr. A; Hemalatha, N.

2013-01-01

The objective of perusing this study is to assess the level of satisfaction of employee retention techniques at GB Engineering Enterprises PVT Limited., Trichy.This study gains significance because of employee retention techniques can be approached from various angles. It is desirable state of existence involving retention strategies generally fall in to one of four categories salary, working conditions, job enrichment and education. These four elements together constitute. The structure of e...

Comparison of isocratic retention models for hydrophilic interaction liquid chromatographic separation of native and fluorescently labeled oligosaccharides

Czech Academy of Sciences Publication Activity Database

Česla, P.; Vaňková, N.; Křenková, Jana; Fischer, J.

2016-01-01

Roč. 1438, MAR (2016), s. 179-188 ISSN 0021-9673 R&D Projects: GA ČR(CZ) GA14-06319S Institutional support: RVO:68081715 Keywords : HILIC * retention * oligosaccharides Subject RIV: CB - Analytical Chemistry , Separation Impact factor: 3.981, year: 2016

Comparison of isocratic retention models for hydrophilic interaction liquid chromatographic separation of native and fluorescently labeled oligosaccharides

Czech Academy of Sciences Publication Activity Database

Česla, P.; Vaňková, N.; Křenková, Jana; Fischer, J.

2016-01-01

Roč. 1438, MAR (2016), s. 179-188 ISSN 0021-9673 R&D Projects: GA ČR(CZ) GA14-06319S Institutional support: RVO:68081715 Keywords : HILIC * retention * oligosaccharides Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 3.981, year: 2016

Fission-product retention in HTGR fuels

International Nuclear Information System (INIS)

Homan, F.J.; Kania, M.J.; Tiegs, T.N.

1982-01-01

Retention data for gaseous and metallic fission products are presented for both Triso-coated and Biso-coated HTGR fuel particles. Performance trends are established that relate fission product retention to operating parameters, such as temperature, burnup, and neutron exposure. It is concluded that Biso-coated particles are not adequately retentive of fission gas or metallic cesium, and Triso-coated particles which retain cesium still lose silver. Design implications related to these performance trends are identified and discussed

Mastery versus the standard proficiency target for basic laparoscopic skill training: effect on skill transfer and retention.

Science.gov (United States)

Kolozsvari, Nicoleta O; Kaneva, Pepa; Brace, Chantalle; Chartrand, Genevieve; Vaillancourt, Marilou; Cao, Jiguo; Banaszek, Daniel; Demyttenaere, Sebastian; Vassiliou, Melina C; Fried, Gerald M; Feldman, Liane S

2011-07-01

Little evidence exists to guide educators in the best way to implement simulation within surgical skills curricula. This study investigated whether practicing a basic Fundamentals of Laparoscopic Surgery (FLS) simulator task [peg transfer (PT)] facilitates learning a more complex skill [intracorporeal suturing (ICS)] and compared the effect of PT training to mastery with training to the passing level on PT retention and on learning ICS. For this study, 98 surgically naïve subjects were randomized to one of three PT training groups: control, standard training, and overtraining. All the participants then trained in ICS. The learning curves for ICS were analyzed by estimating the learning plateau and rate using nonlinear regression. Skill retention was assessed by retesting participants 1 month after training. The groups were compared using analysis of variance (ANOVA). Effectiveness of skill transfer was calculated using the transfer effectiveness ratio (TER). Data are presented as mean±standard deviation (pstandard, and 23 overtrained subjects). The ICS learning plateau rose with increasing PT training (452±10 vs. 459±10 vs. 467±10; p0.5). The PT training took 20±10 min for standard training and 39±20 min for overtraining (pstandard training group, suggesting that PT overtraining took longer than the time saved on ICS training. For surgically naïve subjects, part-task training with PT alone was associated with slight improvements in the learning curve for ICS. However, overtraining with PT did not improve skill retention, and peg training alone was not an efficient strategy for learning ICS.

Motor skill learning, retention, and control deficits in Parkinson's disease.

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Lisa Katharina Pendt

Full Text Available Parkinson's disease, which affects the basal ganglia, is known to lead to various impairments of motor control. Since the basal ganglia have also been shown to be involved in learning processes, motor learning has frequently been investigated in this group of patients. However, results are still inconsistent, mainly due to skill levels and time scales of testing. To bridge across the time scale problem, the present study examined de novo skill learning over a long series of practice sessions that comprised early and late learning stages as well as retention. 19 non-demented, medicated, mild to moderate patients with Parkinson's disease and 19 healthy age and gender matched participants practiced a novel throwing task over five days in a virtual environment where timing of release was a critical element. Six patients and seven control participants came to an additional long-term retention testing after seven to nine months. Changes in task performance were analyzed by a method that differentiates between three components of motor learning prominent in different stages of learning: Tolerance, Noise and Covariation. In addition, kinematic analysis related the influence of skill levels as affected by the specific motor control deficits in Parkinson patients to the process of learning. As a result, patients showed similar learning in early and late stages compared to the control subjects. Differences occurred in short-term retention tests; patients' performance constantly decreased after breaks arising from poorer release timing. However, patients were able to overcome the initial timing problems within the course of each practice session and could further improve their throwing performance. Thus, results demonstrate the intact ability to learn a novel motor skill in non-demented, medicated patients with Parkinson's disease and indicate confounding effects of motor control deficits on retention performance.

HPLC retention thermodynamics of grape and wine tannins.

Science.gov (United States)

Barak, Jennifer A; Kennedy, James A

2013-05-08

The effect of grape and wine tannin structure on retention thermodynamics under reversed-phase high-performance liquid chromatography conditions on a polystyrene divinylbenzene column was investigated. On the basis of retention response to temperature, an alternative retention factor was developed to approximate the combined temperature response of the complex, unresolvable tannin mixture. This alternative retention factor was based upon relative tannin peak areas separated by an abrupt change in solvent gradient. Using this alternative retention factor, retention thermodynamics were calculated. Van't Hoff relationships of the natural log of the alternative retention factor against temperature followed Kirchoff's relationship. An inverse quadratic equation was fit to the data, and from this the thermodynamic parameters for tannin retention were calculated. All tannin fractions exhibited exothermic, spontaneous interaction, with enthalpy-entropy compensation observed. Normalizing for tannin size, distinct tannin compositional effects on thermodynamic parameters were observed. The results of this study indicate that HPLC can be valuable for measuring the thermodynamics of tannin interaction with a hydrophobic surface and provides a potentially valuable alternative to calorimetry. Furthermore, the information gathered may provide insight into understanding red wine astringency quality.

Soil Water Retention Curve

Science.gov (United States)

Johnson, L. E.; Kim, J.; Cifelli, R.; Chandra, C. V.

2016-12-01

Potential water retention, S, is one of parameters commonly used in hydrologic modeling for soil moisture accounting. Physically, S indicates total amount of water which can be stored in soil and is expressed in units of depth. S can be represented as a change of soil moisture content and in this context is commonly used to estimate direct runoff, especially in the Soil Conservation Service (SCS) curve number (CN) method. Generally, the lumped and the distributed hydrologic models can easily use the SCS-CN method to estimate direct runoff. Changes in potential water retention have been used in previous SCS-CN studies; however, these studies have focused on long-term hydrologic simulations where S is allowed to vary at the daily time scale. While useful for hydrologic events that span multiple days, the resolution is too coarse for short-term applications such as flash flood events where S may not recover its full potential. In this study, a new method for estimating a time-variable potential water retention at hourly time-scales is presented. The methodology is applied for the Napa River basin, California. The streamflow gage at St Helena, located in the upper reaches of the basin, is used as the control gage site to evaluate the model performance as it is has minimal influences by reservoirs and diversions. Rainfall events from 2011 to 2012 are used for estimating the event-based SCS CN to transfer to S. As a result, we have derived the potential water retention curve and it is classified into three sections depending on the relative change in S. The first is a negative slope section arising from the difference in the rate of moving water through the soil column, the second is a zero change section representing the initial recovery the potential water retention, and the third is a positive change section representing the full recovery of the potential water retention. Also, we found that the soil water moving has traffic jam within 24 hours after finished first

The Picmonic® Learning System: enhancing memory retention of medical sciences, using an audiovisual mnemonic Web-based learning platform

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Yang A

2014-05-01

Full Text Available Adeel Yang,1,* Hersh Goel,1,* Matthew Bryan,2 Ron Robertson,1 Jane Lim,1 Shehran Islam,1 Mark R Speicher2 1College of Medicine, The University of Arizona, Tucson, AZ, USA; 2Arizona College of Osteopathic Medicine, Midwestern University, Glendale, AZ, USA *These authors contributed equally to this work Background: Medical students are required to retain vast amounts of medical knowledge on the path to becoming physicians. To address this challenge, multimedia Web-based learning resources have been developed to supplement traditional text-based materials. The Picmonic® Learning System (PLS; Picmonic, Phoenix, AZ, USA is a novel multimedia Web-based learning platform that delivers audiovisual mnemonics designed to improve memory retention of medical sciences. Methods: A single-center, randomized, subject-blinded, controlled study was conducted to compare the PLS with traditional text-based material for retention of medical science topics. Subjects were randomly assigned to use two different types of study materials covering several diseases. Subjects randomly assigned to the PLS group were given audiovisual mnemonics along with text-based materials, whereas subjects in the control group were given the same text-based materials with key terms highlighted. The primary endpoints were the differences in performance on immediate, 1 week, and 1 month delayed free-recall and paired-matching tests. The secondary endpoints were the difference in performance on a 1 week delayed multiple-choice test and self-reported satisfaction with the study materials. Differences were calculated using unpaired two-tailed t-tests. Results: PLS group subjects demonstrated improvements of 65%, 161%, and 208% compared with control group subjects on free-recall tests conducted immediately, 1 week, and 1 month after study of materials, respectively. The results of performance on paired-matching tests showed an improvement of up to 331% for PLS group subjects. PLS group

28 CFR 345.67 - Retention of benefits.

Science.gov (United States)

2010-07-01

... INDUSTRIES (FPI) INMATE WORK PROGRAMS Inmate Pay and Benefits § 345.67 Retention of benefits. (a) Job retention. Ordinarily, when an inmate is absent from the job for a significant period of time, the SOI will... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Retention of benefits. 345.67 Section 345...

Novel word retention in bilingual and monolingual speakers

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Pui Fong eKan

2014-09-01

Full Text Available The goal of this research was to examine word retention in bilinguals and monolinguals. Long-term word retention is an essential part of vocabulary learning. Previous studies have documented that bilinguals outperform monolinguals in terms of retrieving newly-exposed words. Yet, little is known about whether or to what extent bilinguals are different from monolinguals in word retention. Participants were 30 English-speaking monolingual adults and 30 bilingual adults who speak Spanish as a home language and learned English as a second language during childhood. In a previous study (Kan, Sadagopan, Janich, & Andrade, 2014, the participants were exposed to the target novel words in English, Spanish, and Cantonese. In this current study, word retention was measured a week after the fast mapping task. No exposures were given during the one-week interval. Results showed that bilinguals and monolinguals retain a similar number of words. However, participants produced more words in English than in either Spanish or Cantonese. Correlation analyses revealed that language knowledge plays a role in the relationships between fast mapping and word retention. Specifically, within- and across-language relationships between bilinguals’ fast mapping and word retention were found in Spanish and English, by contrast, within-language relationships between monolinguals’ fast mapping and word retention were found in English and across-language relationships between their fast mapping and word retention performance in English and Cantonese. Similarly, bilinguals differed from monolinguals in the relationships among the word retention scores in three languages. Significant correlations were found among bilinguals’ retention scores. However, no such correlations were found among monolinguals’ retention scores. The overall findings suggest that bilinguals’ language experience and language knowledge most likely contribute to how they learn and retain new words.

Novel word retention in bilingual and monolingual speakers.

Science.gov (United States)

Kan, Pui Fong; Sadagopan, Neeraja

2014-01-01

The goal of this research was to examine word retention in bilinguals and monolinguals. Long-term word retention is an essential part of vocabulary learning. Previous studies have documented that bilinguals outperform monolinguals in terms of retrieving newly-exposed words. Yet, little is known about whether or to what extent bilinguals are different from monolinguals in word retention. Participants were 30 English-speaking monolingual adults and 30 bilingual adults who speak Spanish as a home language and learned English as a second language during childhood. In a previous study (Kan et al., 2014), the participants were exposed to the target novel words in English, Spanish, and Cantonese. In this current study, word retention was measured a week after the fast mapping task. No exposures were given during the one-week interval. Results showed that bilinguals and monolinguals retain a similar number of words. However, participants produced more words in English than in either Spanish or Cantonese. Correlation analyses revealed that language knowledge plays a role in the relationships between fast mapping and word retention. Specifically, within- and across-language relationships between bilinguals' fast mapping and word retention were found in Spanish and English, by contrast, within-language relationships between monolinguals' fast mapping and word retention were found in English and across-language relationships between their fast mapping and word retention performance in English and Cantonese. Similarly, bilinguals differed from monolinguals in the relationships among the word retention scores in three languages. Significant correlations were found among bilinguals' retention scores. However, no such correlations were found among monolinguals' retention scores. The overall findings suggest that bilinguals' language experience and language knowledge most likely contribute to how they learn and retain new words.

The structural neural substrate of subjective happiness.

Science.gov (United States)

Sato, Wataru; Kochiyama, Takanori; Uono, Shota; Kubota, Yasutaka; Sawada, Reiko; Yoshimura, Sayaka; Toichi, Motomi

2015-11-20

Happiness is a subjective experience that is an ultimate goal for humans. Psychological studies have shown that subjective happiness can be measured reliably and consists of emotional and cognitive components. However, the neural substrates of subjective happiness remain unclear. To investigate this issue, we used structural magnetic resonance imaging and questionnaires that assessed subjective happiness, the intensity of positive and negative emotional experiences, and purpose in life. We found a positive relationship between the subjective happiness score and gray matter volume in the right precuneus. Moreover, the same region showed an association with the combined positive and negative emotional intensity and purpose in life scores. Our findings suggest that the precuneus mediates subjective happiness by integrating the emotional and cognitive components of happiness.

Probes for dark matter physics

Science.gov (United States)

Khlopov, Maxim Yu.

The existence of cosmological dark matter is in the bedrock of the modern cosmology. The dark matter is assumed to be nonbaryonic and consists of new stable particles. Weakly Interacting Massive Particle (WIMP) miracle appeals to search for neutral stable weakly interacting particles in underground experiments by their nuclear recoil and at colliders by missing energy and momentum, which they carry out. However, the lack of WIMP effects in their direct underground searches and at colliders can appeal to other forms of dark matter candidates. These candidates may be weakly interacting slim particles, superweakly interacting particles, or composite dark matter, in which new particles are bound. Their existence should lead to cosmological effects that can find probes in the astrophysical data. However, if composite dark matter contains stable electrically charged leptons and quarks bound by ordinary Coulomb interaction in elusive dark atoms, these charged constituents of dark atoms can be the subject of direct experimental test at the colliders. The models, predicting stable particles with charge ‑ 2 without stable particles with charges + 1 and ‑ 1 can avoid severe constraints on anomalous isotopes of light elements and provide solution for the puzzles of dark matter searches. In such models, the excessive ‑ 2 charged particles are bound with primordial helium in O-helium atoms, maintaining specific nuclear-interacting form of the dark matter. The successful development of composite dark matter scenarios appeals for experimental search for doubly charged constituents of dark atoms, making experimental search for exotic stable double charged particles experimentum crucis for dark atoms of composite dark matter.

Low episodic memory performance in cognitively normal elderly subjects is associated with increased posterior cingulate gray matter N-acetylaspartate: a 1H MRSI study at 7 Tesla.

Science.gov (United States)

Schreiner, Simon J; Kirchner, Thomas; Wyss, Michael; Van Bergen, Jiri M G; Quevenco, Frances C; Steininger, Stefanie C; Griffith, Erica Y; Meier, Irene; Michels, Lars; Gietl, Anton F; Leh, Sandra E; Brickman, Adam M; Hock, Christoph; Nitsch, Roger M; Pruessmann, Klaas P; Henning, Anke; Unschuld, Paul G

2016-12-01

Low episodic memory performance characterizes elderly subjects at increased risk for Alzheimer's disease (AD) and may reflect neuronal dysfunction within the posterior cingulate cortex and precuneus (PCP) region. To investigate a potential association between cerebral neurometabolism and low episodic memory in the absence of cognitive impairment, tissue-specific magnetic resonance spectroscopic imaging at ultrahigh field strength of 7 Tesla was used to investigate the PCP region in a healthy elderly study population (n = 30, age 70 ± 5.7 years, Mini-Mental State Examination 29.4 ± 4.1). The Verbal Learning and Memory Test (VLMT) was administered as part of a neuropsychological battery for assessment of episodic memory performance. Significant differences between PCP gray and white matter could be observed for glutamate-glutamine (p = 0.001), choline (p = 0.01), and myo-inositol (p = 0.02). Low Verbal Learning and Memory Test performance was associated with high N-acetylaspartate in PCP gray matter (p = 0.01) but not in PCP white matter. Our data suggest that subtle decreases in episodic memory performance in the elderly may be associated with increased levels of N-acetylaspartate as a reflection of increased mitochondrial energy capacity in PCP gray matter. Copyright © 2016 Elsevier Inc. All rights reserved.

International perspectives on retention and persistence

Directory of Open Access Journals (Sweden)

Gary Burkholder

2014-06-01

Full Text Available Access to higher education globally is increasing dramatically; attainment of tertiary degrees is a high priority, as educational attainment is associated with increased personal incomes as well as growth of the middle class in developing countries. The purpose of this essay is to briefly examine retention and persistence issues from a global perspective, review some retention strategies that have been employed at schools outside the United States, and to identify several key factors that related to retention and persistence globally, including access, infrastructure, financial consideration, and readiness for tertiary education.  There exists an opportunity to utilize knowledge gained in the evolution of the higher education system in the United States to help address the problems associated with retention and persistence.   DOI: 10.18870/hlrc.v4i2.208

Gray matter network disruptions and amyloid beta in cognitively normal adults.

Science.gov (United States)

Tijms, Betty M; Kate, Mara Ten; Wink, Alle Meije; Visser, Pieter Jelle; Ecay, Mirian; Clerigue, Montserrat; Estanga, Ainara; Garcia Sebastian, Maite; Izagirre, Andrea; Villanua, Jorge; Martinez Lage, Pablo; van der Flier, Wiesje M; Scheltens, Philip; Sanz Arigita, Ernesto; Barkhof, Frederik

2016-01-01

Gray matter networks are disrupted in Alzheimer's disease (AD). It is unclear when these disruptions start during the development of AD. Amyloid beta 1-42 (Aβ42) is among the earliest changes in AD. We studied, in cognitively healthy adults, the relationship between Aβ42 levels in cerebrospinal fluid (CSF) and single-subject cortical gray matter network measures. Single-subject gray matter networks were extracted from structural magnetic resonance imaging scans in a sample of cognitively healthy adults (N = 185; age range 39-79, mini-mental state examination >25, N = 12 showed abnormal Aβ42 level and for 90 anatomical areas. Associations between continuous Aβ42 CSF levels and single-subject cortical gray matter network measures were tested. Smoothing splines were used to determine whether a linear or nonlinear relationship gave a better fit to the data. Lower Aβ42 CSF levels were linearly associated at whole brain level with lower connectivity density, and nonlinearly with lower clustering values and higher path length values, which is indicative of a less-efficient network organization. These relationships were specific to medial temporal areas, precuneus, and the middle frontal gyrus (all p levels can be related to gray matter networks disruptions. Copyright © 2016 Elsevier Inc. All rights reserved.

Strategies for improving employee retention.

Science.gov (United States)

Verlander, Edward G; Evans, Martin R

2007-03-28

This article proposes a solution to the perennial problem of talent retention in the clinical laboratory. It includes the presentation of 12 strategies that may be used to significantly improve institutional identity formation and establishment of the psychological contract that employees form with laboratory management. Identity formation and psychological contracting are deemed as essential in helping reduce employee turnover and increase retention. The 12 conversational strategies may be used as a set of best practices for all employees, but most importantly for new employees, and should be implemented at the critical moment when employees first join the laboratory. This time is referred to as "retention on-boarding"--the period of induction and laboratory orientation. Retention on-boarding involves a dialogue between employees and management that is focused on the psychological, practical, cultural, and political dimensions of the laboratory. It is placed in the context of the modern clinical laboratory, which is faced with employing and managing Generation X knowledge workers. Specific topics and broad content areas of those conversations are outlined.

Sorption of polycyclic aromatic hydrocarbons on particulate organic matters

International Nuclear Information System (INIS)

Guo Xueyan; Luo Lei; Ma Yibing; Zhang Shuzhen

2010-01-01

Particulate organic matter (POM) is a key organic matter fraction which can influence soil fertility. Its interactions with hydrophobic organic pollutants (HOCs) have not been characterized and the mechanisms of retention of HOCs by POM remain unclear. In the present study, sorption behaviors of polycyclic aromatic hydrocarbons (PAHs) naphthalene (NAP), phenanthrene (PHE), and pyrene (PYR) by POMs separated from different soils were examined and the POMs were characterized by elemental analysis, solid state 13 C NMR, and Fourier transform infrared spectroscopy (FT-IR). The results indicated that POMs were mainly composed of aliphatic components with high polarity. The different original POMs showed similar chemical composition and configuration. Sorption behaviors of PAHs indicated that there was no significant difference in sorption capacity among the POMs. Sorption of NAP and PHE by POMs displayed a nonlinear isotherm, while sorption of PYR yielded a linear isotherm. No significant hysteresis and ionic strength effect were observed for PAH desorption from the POMs.

Review of retention strategies in longitudinal studies and application to follow-up of ICU survivors.

Science.gov (United States)

Tansey, Catherine M; Matté, Andrea L; Needham, Dale; Herridge, Margaret S

2007-12-01

To review the literature on retention strategies in follow-up studies and their relevance to critical care and to comment on the Toronto experience with the acute respiratory distress syndrome (ARDS) and severe acute respiratory syndrome (SARS) follow-up studies. Literature review and two cohort studies in a tertiary care hospital in Toronto, Canada. ARDS and SARS patients. Review articles from the social sciences and medicine are summarized and our own experience with two longitudinal studies is drawn upon to elucidate strategies that can be successfully used to attenuate participant drop-out from longitudinal studies. Three key areas for retention of subjects are identified from the literature: (a) respect for patients: respect for their ideas and their time commitment to the research project; (b) tracking: collect information on many patient contacts at the initiation of the study and outline tracking procedures for subjects lost to follow-up; and (c) study personnel: interpersonal skills must be reinforced, flexible working hours mandated, and support offered. Our 5-year ARDS and 1-year SARS study retention rates were 86% and 91%, respectively, using these methods. Strategies to reduce patient attrition are time consuming but necessary to preserve internal and external validity. When the follow-up system is working effectively, researchers can acquire the necessary data to advance knowledge in their field and patients are satisfied that they have an important role to play in the research project.

"To be or not to be Retained … That's the Question!" Retention, Self-esteem, Self-concept, Achievement Goals, and Grades.

Science.gov (United States)

Peixoto, Francisco; Monteiro, Vera; Mata, Lourdes; Sanches, Cristina; Pipa, Joana; Almeida, Leandro S

2016-01-01

Keeping students back in the same grade - retention - has always been a controversial issue in Education, with some defending it as a beneficial remedial practice and others arguing against its detrimental effects. This paper undertakes an analysis of this issue, focusing on the differences in student motivation and self-related variables according to their retention related status, and the interrelationship between retention and these variables. The participants were 695 students selected from two cohorts (5th and 7th graders) of a larger group of students followed over a 3-year project. The students were assigned to four groups according to their retention-related status over time: (1) students with past and recent retention; (2) students with past but no recent retention; (3) students with no past but recent retention; (4) students with no past or recent retention. Measures of achievement goal orientations, self-concept, self-esteem, importance given to school subjects and Grade Point Average (GPA) were collected for all students. Repeated measures MANCOVA analyses were carried out showing group differences in self-esteem, academic self-concept, importance attributed to academic competencies, task and avoidance orientation and academic achievement. To attain a deeper understanding of these results and to identify profiles across variables, a cluster analysis based on achievement goals was conducted and four clusters were identified. Students who were retained at the end of the school year are mainly represented in clusters with less adaptive motivational profiles and almost absent from clusters exhibiting more adaptive ones. Findings highlight that retention leaves a significant mark that remains even when students recover academic achievement and retention is in the distant past. This is reflected in the low academic self-concept as well as in the devaluation of academic competencies and in the avoidance orientation which, taken together, can undermine students

phosphorus retention data and metadata

Science.gov (United States)

phosphorus retention in wetlands data and metadataThis dataset is associated with the following publication:Lane , C., and B. Autrey. Phosphorus retention of forested and emergent marsh depressional wetlands in differing land uses in Florida, USA. Wetlands Ecology and Management. Springer Science and Business Media B.V;Formerly Kluwer Academic Publishers B.V., GERMANY, 24(1): 45-60, (2016).

'The body does matter': Women as embodied social subjects in Angela Carter's Nights at the Circus

Directory of Open Access Journals (Sweden)

Milosavljević Tatjana B.

2017-01-01

Full Text Available Postmodernism posed a crucial ontological challenge to reality, questioning what constitutes the real world, simultaneously interrogating the horizon of representation of this unstable reality in fiction. Feminism on the other hand equipped us with critical tools for interpreting the reality of being in the world in a gendered body, as well as with a conceptual apparatus for interpreting the manifold institutional and private oppressions of women's bodies that play out in women's daily lives and in the discourses that shape them, literary discourse being one of them. This paper argues that Angela Carter's 1984 novel Nights at the Circus, which is widely held as a postfeminist text due to its narrative commitment to transcending gender binaries, essentially uses the strategies of postmodern storytelling and characterization in order to explore women's embodied potentialities of agency i.e. their construction of subjectivity through body. We will argue that the hybrid magic realist narrative constructs Fevvers' body as a titillating postmodern performance, ontologically illusive and elusive, yet it grounds that same body in various socially effected predicaments and experiences that serve to show that even in the midst of a play of signifiers, in Patricia Waugh's words, 'the body does matter, at least to what has been the dominant perspective within British female fiction' (Waugh, 2006, p. 196. In other words, it may be argued that Carter's novel is invested in traditional second-wave feminist politics to the extent that it shows that a woman's body is an indispensable medium of being in the world with material consequences that bear on the formation of her subjectivity and possibility of agency, and through which she acts out her relationships to others and is acted upon.

Accuracy of 24-h whole-body (skeletal) retention of diphosphonate measurements

International Nuclear Information System (INIS)

Fogelman, I.; Scullion, J.E.; Bessent, R.; Cuthbert, G.F.

1982-01-01

The 24-h whole-body retention (WBR) of diphosphonate was a valuable test for the assessment of skeletal metabolism. However, the reproducibility, accuracy and possible sources of error in WBR measurements have not previously been studied. In 21 paired studies the technique was found to be highly reproducible (r=0.998, R<0.0001). The coefficient of variation for whole-body counts on day 1 was 0.1% and on day 2, 1.1%. A phantom was used to assess the possible error introduced by redistribution of tracer. The net whole-body count of the phantom representing the 24-h distribution was 98% of that of a uniform phantom. Ten subjects were counted twice within a few minutes to study the effect of repositioning, and showed a mean difference between counts of only 0.8%. Eleven subjects with traumatic fractures were studied to assess the possible contribution of focal lesions to WBR. It was found that nine subjects had normal values for WBR, while two had minimally elevated results. Twenty patients with renal disease but no apparent skeletal disease were also studied to assess the possible contribution of soft-tissue retention to WBR. A significant correlation between serum creatinine and WBR was found (r=0.72, P<0.001). However WBR results were always normal when serum creatinine values were <130 μmol/1. It is suggested that WBR measurement is accurate and the technique is hgihly reproducible. The presence of a focal lesion is unlikely to affect a WBR result significantly and if serum creatinine is the normal range then WBR can be assumed to reflect skeletal metabolism without further concern as to renal function. (orig.)

Digestive physiology of captive giant anteaters (Myrmecophaga tridactyla): determinants of faecal dry matter content.

Science.gov (United States)

Gull, J M; Stahl, M; Osmann, C; Ortmann, S; Kreuzer, M; Hatt, J-M; Clauss, M

2015-06-01

Giant anteaters (Myrmecophaga tridactyla) are specialized insectivores and consume mainly ants and termites in the wild. In captivity, giant anteaters are either fed a complete diet, or a combination of a domestic carnivore diet with leaf eater pellets, or a traditional gruel-type diet. Soft faeces are a frequently encountered problem with this type of feeding. In the present study, we analysed diet and faeces composition, calculated digestibility and measured mean retention time on various diets in eight giant anteaters (total of n = 64 experiments). The results suggest that the digestive physiology of giant anteaters is similar to that of domestic dogs and cats in terms of nutrient digestibility and digesta retention. When testing correlations between faecal dry matter content and other variables, no relationship with dietary crude fibre content or mean digesta retention time could be detected. However, acid insoluble ash intake was significantly and positively correlated with faecal dry matter content. The amount of acid insoluble ash excreted with the faeces was higher than that ingested with the diet offered, indicating that the giant anteaters ingested soil from their enclosure of up to 93 g per day. This finding is consistent with observation of faeces of wild giant anteaters that contain soil or sand most likely due to indiscriminate feeding. It also corresponds to reports that indigestible materials such as peat, soil, chitin or cellulose contribute to a firmer faecal consistency in various carnivore species. Therefore, offering giant anteaters the opportunity to voluntarily ingest soil from their enclosure might be beneficial. Journal of Animal Physiology and Animal Nutrition © 2014 Blackwell Verlag GmbH.

Implications of invalidity of Data Retention Directive to telecom operators

Directory of Open Access Journals (Sweden)

Darja LONČAR DUŠANOVIĆ

2014-12-01

Full Text Available Obligation for telecom operators to retain traffic and location data for combating crime purposes had been controversial ever since the adoption of the Data Retention Directive in 2006 because of its inherent negative impact on the fundamental right to privacy and personal data protection. However, the awaited judgment of the CJEU in April this year, which declared the Directive invalid, did not so far resolve the ambiguity of the issue. Namely, having in mind that half a year later, some countries did not amend their national data retention legislations (yet to comply with the aforementioned CJEU judgment, telecom operators as addresses of this obligation are in uncertain legal situation which could be called “lose-lose” situation. Also, the emphasis from the question of proportionality between data privacy and public security is shifted to the question of existence of valid legal basis for data processing (retaining data and providing them to authorities in the new legal environment in which national and EU law are still not in compliance. In this paper the author examines the implications of the CJEU judgment to national EU legislation, telecom operators and data subjects, providing comparative analysis of national data retention legislation status in EU member states. The existence of valid legal basis for data processing is examined within EU law sources, including within proposed EU General Data Protection Regulation and opinions of the relevant data protection bodies (e.g. Article 29 Working Party.

Employee retention: a customer service approach.

Science.gov (United States)

Gerson, Richard F

2002-01-01

Employee retention is a huge problem. There are staff shortages in radiology because not enough people are entering the profession; too many people are leaving the profession for retirement, higher-paying jobs or jobs with less stress; and there are not enough opportunities for career advancement. Staff shortages are exacerbated by difficulty in retaining people who enter the profession. While much work has been focused on recruitment and getting more people "in the front door," I suggest that the bulk of future efforts be focused on employee retention and "closing the back door." Employee retention must be an ongoing process, not a program. Approaches to employee retention that focus on external things, i.e., things that the company can do to or for the employee, generally are not successful. The truth is that employee retention processes must focus on what the employee gets out of the job. The process must be a benefits-based approach that helps employees answer the question, "What's in it for me?" The retention processes must be ongoing and integrated into the daily culture of the company. The best way to keep your employees is to treat them like customers. Customer service works for external customers. We treat them nicely. We work to satisfy them. We help them achieve their goals. Why not do the same for our employees? If positive customer service policies and practices can satisfy and keep external customers, why not adapt these policies and practices for employees? And, there is a service/satisfaction link between employee retention and higher levels of customer satisfaction. Customers prefer dealing with the same employees over and over again. Employee turnover destroys a customer's confidence in the company. Just like a customer does not want to have to "train and educate" a new provider, they do not want to do the same for your "revolving door" employees. So, the key is to keep employees so they in turn will help you keep your customers. Because the

Deuterium retention in molten salt electrodeposition tungsten coatings

International Nuclear Information System (INIS)

Zhou, Hai-Shan; Xu, Yu-Ping; Sun, Ning-Bo; Zhang, Ying-Chun; Oya, Yasuhisa; Zhao, Ming-Zhong; Mao, Hong-Min; Ding, Fang; Liu, Feng; Luo, Guang-Nan

2016-01-01

Highlights: • We investigate D retention in electrodeposition W coatings. • W coatings are exposed to D plasmas in the EAST tokamak. • A cathodic current density dependence on D retention is found. • Electrodeposition W exhibits lower D retention than VPS-W. - Abstract: Molten salt electrodeposition is a promising technology to manufacture the first wall of a fusion reactor. Deuterium (D) retention behavior in molten salt electrodeposition tungsten (W) coatings has been investigated by D-plasma exposure in the EAST tokamak and D-ion implantation in an ion beam facility. Tokamak exposure experiments demonstrate that coatings prepared with lower current density exhibit less D retention and milder surface damage. Deuterium-ion implantation experiments indicate the D retention in the molten salt electrodeposition W is less than that in vacuum plasma spraying W and polycrystalline W.

Deuterium retention in molten salt electrodeposition tungsten coatings

Energy Technology Data Exchange (ETDEWEB)

Zhou, Hai-Shan [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei (China); Xu, Yu-Ping [Science Island Branch of Graduate School, University of Science and Technology of China, Hefei (China); Sun, Ning-Bo; Zhang, Ying-Chun [School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing (China); Oya, Yasuhisa [Radioscience Research Laboratory, Faculty of Science, Shizuoka University, Shizuoka (Japan); Zhao, Ming-Zhong [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei (China); Mao, Hong-Min [Science Island Branch of Graduate School, University of Science and Technology of China, Hefei (China); Ding, Fang; Liu, Feng [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei (China); Luo, Guang-Nan, E-mail: gnluo@ipp.ac.cn [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei (China); Science Island Branch of Graduate School, University of Science and Technology of China, Hefei (China); Hefei Center for Physical Science and Technology, Hefei (China); Hefei Science Center of Chinese Academy of Science, Hefei (China)

2016-12-15

Highlights: • We investigate D retention in electrodeposition W coatings. • W coatings are exposed to D plasmas in the EAST tokamak. • A cathodic current density dependence on D retention is found. • Electrodeposition W exhibits lower D retention than VPS-W. - Abstract: Molten salt electrodeposition is a promising technology to manufacture the first wall of a fusion reactor. Deuterium (D) retention behavior in molten salt electrodeposition tungsten (W) coatings has been investigated by D-plasma exposure in the EAST tokamak and D-ion implantation in an ion beam facility. Tokamak exposure experiments demonstrate that coatings prepared with lower current density exhibit less D retention and milder surface damage. Deuterium-ion implantation experiments indicate the D retention in the molten salt electrodeposition W is less than that in vacuum plasma spraying W and polycrystalline W.

Brain parenchymal density measurements by CT in demented subjects and normal controls

International Nuclear Information System (INIS)

Gado, M.; Danziger, W.L.; Chi, D.; Hughes, C.P.; Coben, L.A.

1983-01-01

Parachymal density measurements of 14 regions of gray and white matter from each cerebral hemisphere were made from CT scans of 25 subjects who had varying degrees of dementia as measured by a global Clinical Dementia Rating, and also from CT scans of 33 normal control subjects. There were few significant differences between the two groups in the mean density value for each of the regions examined, although several individual psychometric tests did correlate with density changes. Moreover, for six regions in the cerebral cortex, and for one region in the thalamus of each hemisphere, we found no significant correlation between the gray-white matter density difference and dementia. There was, however, a loss of the discriminability between the gray and white matter with an increase in the size of the ventricles. These findings may be attributed to the loss of white matter volume

NASA's Universe of Learning: The Integral Role of Research Astronomers and Other Subject Matter Experts

Science.gov (United States)

Lee, Janice; Universe of Learning Team

2018-01-01

Astronomy seeks to understand the workings of the Universe on its largest scales, and to answer fundamental questions about the story of our origins. The science of astronomy thus naturally lends itself to informal education and public outreach activities, as it broadly captures the human imagination. There are at least three overall goals for investment of resources in Astronomy E/PO: to interest students in pursuing STEM education and careers; to develop Astronomy as context for teaching more basic physical and computer science in service of US National Education Goals; to help motivate continued public support of federally funded Astronomy research and technology development. Providing a full spectrum of opportunities for the public to learn about recent Astronomy discoveries is key to achieving these societal goals. Thus, the E/PO professional community must have an understanding of recent scientific/technological results, and engage with the researchers who are creating new knowledge to explicate that knowledge to the public. It stands to reason that researchers (or “subject matter experts, SMEs”) must be involved in and remain connected to the E/PO endeavor. In this talk, I will describe how research astronomers and other SMEs play an integral role in a full range of informal education programming developed by the NASA Universe of Learning collaboration, and opportunities to get involved.

Novel word retention in sequential bilingual children.

Science.gov (United States)

Kan, Pui Fong

2014-03-01

Children's ability to learn and retain new words is fundamental to their vocabulary development. This study examined word retention in children learning a home language (L1) from birth and a second language (L2) in preschool settings. Participants were presented with sixteen novel words in L1 and in L2 and were tested for retention after either a 2-month or a 4-month delay. Results showed that children retained more words in L1 than in L2 for both of the retention interval conditions. In addition, children's word retention was associated with their existing language knowledge and their fast-mapping performance within and across language. The patterns of association, however, were different between L1 and L2. These findings suggest that children's word retention might be related to the interactions of various components that are operating within a dynamic system.

A Cost Benefit Analysis Between the Current Naval Officer Retention Bonus Plan and the Enlisted Retention Bonus Plan

Science.gov (United States)

2016-06-01

that personnel targeted for retention had a direct ability to affect the success of the transaction and company. High potential, job function, job level...and job title rounded out the top five reasons personnel were targeted for retention . In brief, this study found that slightly more than half of...lower income may value the job security provided by service in the military, thus making retention in the military a more attractive option. 4

Feasibility of dialectical behavior therapy with suicidal and self-harming adolescents with multi-problems: training, adherence, and retention.

Science.gov (United States)

Tørmoen, A J; Grøholt, B; Haga, E; Brager-Larsen, A; Miller, A; Walby, F; Stanley, B; Mehlum, L

2014-01-01

We evaluated the feasibility of DBT training, adherence, and retention preparing for a randomized controlled trial of Dialectical Behavior Therapy (DBT) adapted for Norwegian adolescents engaging in self-harming behavior and diagnosed with features of borderline personality disorder. Therapists were intensively trained and evaluated for adherence. Adherence scores, treatment retention, and present and previous self-harm were assessed. Twenty-seven patients were included (mean age 15.7 years), all of them with recent self-harming behaviors and at least 3 features of Borderline Personality Disorder. Therapists were adherent and 21 (78%) patients completed the whole treatment. Three subjects reported self-harm at the end of treatment, and urges to self-harm decreased. At follow up, 7 of 10 subjects reported no self-harm. DBT was found to be well accepted and feasible. Randomized controlled trials are required to test the effectiveness of DBT for adolescents.

White matter fibertracking in first-episode schizophrenia, schizoaffective patients and subjects at ultra-high risk of psychosis

NARCIS (Netherlands)

Peters, Bart D.; de Haan, Lieuwe; Dekker, Nienke; Blaas, Jorik; Becker, Hiske E.; Dingemans, Peter M.; Akkerman, Erik M.; Majoie, Charles B.; van Amelsvoort, Therèse; den Heeten, Gerard J.; Linszen, Don H.

2008-01-01

There is increasing evidence of white matter pathology in schizophrenia. The aim of this study was to examine whether white matter abnormalities found with diffusion tensor imaging (DTI) in previous schizophrenia studies are present in the early phase of the illness. DTI was performed at 3 T on 10

Frontal and subcortical grey matter reductions in PTSD.

Science.gov (United States)

O'Doherty, Daniel C M; Tickell, Ashleigh; Ryder, Will; Chan, Charles; Hermens, Daniel F; Bennett, Maxwell R; Lagopoulos, Jim

2017-08-30

Post-traumatic stress disorder (PTSD) is characterised by a range of debilitating psychological, physical and cognitive symptoms. PTSD has been associated with grey matter atrophy in limbic and frontal cortical brain regions. However, previous studies have reported heterogeneous findings, with grey matter changes observed beyond limbic/frontal areas. Seventy-five adults were recruited from the community, 25 diagnosed with PTSD along with 25 healthy and 25 trauma exposed age and gender matched controls. Participants underwent clinical assessment and magnetic resonance imaging. The data-analyses method Voxel Based Morphometry (VBM) was used to estimate cortical grey matter volumes. When compared to both healthy and trauma exposed controls, PTSD subjects demonstrated decreased grey matter volumes within subcortical brain regions-including the hippocampus and amygdala-along with reductions in the anterior cingulate cortex, frontal medial cortex, middle frontal gyrus, superior frontal gyrus, paracingulate gyrus, and precuneus cortex. Significant negative correlations were found between total CAPS lifetime clinical scores/sub-scores and GM volume of both the PTSD and TC groups. GM volumes of the left rACC and right amygdala showed a significant negative correlation within PTSD diagnosed subjects. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Regional White Matter Decreases in Alzheimer's Disease Using Optimized Voxel-Based Morphometry

International Nuclear Information System (INIS)

Shuyu Li; Fang Pu; Feng Shi; Sheng Xie; Yinhua Wang; Tianzi Jiang

2008-01-01

Background: Most studies that attempt to clarify structural abnormalities related to functional disconnection in patients with Alzheimer's disease (AD) have focused on exploring pathological changes in cortical gray matter. However, white matter fibers connecting these cerebral areas may also be abnormal. Purpose: To investigate the regional changes of white matter volume in patients with AD compared to healthy subjects. Material and Methods: White matter volume changes in whole-brain magnetic resonance images acquired from 19 patients with AD and 20 healthy subjects (control group) were observed using the optimized voxel-based morphometry (VBM) method. In addition, the corpus callosum (CC) of AD patients and the control group was investigated further by outlining manually the boundary of the CC on a midsagittal slice. Each area of the CC was then corrected by dividing each subject's intracranial area in the midsagittal plane. Results: Compared with the control group, AD patients showed significantly reduced white matter volumes in the posterior part of the CC and the temporal lobe in the left and right hemispheres. Moreover, the voxel showing peak statistical difference in the posterior of the CC was left sided. The five subdivisions of the CC were also significantly smaller among the AD patients relative to the control group. Conclusion: Our findings suggest that these abnormalities in white matter regions may contribute to the functional disconnections in AD

Promoting Special Educator Teacher Retention

OpenAIRE

Jeremy E. Vittek

2015-01-01

This article is a critical review of the literature on special education teacher attrition and retention. The research focused on journal articles from 2004 to present. The results of the study helped define special educator attrition and retention. The major themes present in the findings were job satisfaction, administrative support, induction programs, and mentoring. The literature shows a clear need for comprehensi...

Flocculation of retention pond water

International Nuclear Information System (INIS)

Hart, B.T.; McGregor, R.J.

1982-05-01

An integral part of the water management strategy proposed by Ranger Uranium Mining Pty. Ltd. involves the collection of runoff water in a series of retention ponds. This water will subsequently be used in the uranium milling plant or released to Magela Creek. Runoff water collected during the wet season caused a section of Magela Creek to become turbid when it was released. The eroded material causing the turbidity was very highly dispersed and showed little tendency to sediment out in the retention ponds. Results of a preliminary study to determine the feasibility of clarifying retention pond water by flocculation with alum are presented. A concentration of 30 Mg/L alum reduced turbidity from an initial 340 NTU to less than 30 NTU in four hours

Nitrogen Saturation in Highly Retentive Watersheds?

Science.gov (United States)

Daley, M. L.; McDowell, W. H.

2009-12-01

Watershed managers are often concerned with minimizing the amount of N delivered to N-limited estuaries and coastal zones. A major concern is that watersheds might reach N saturation, in which N delivered to coastal zones increases due to declines in the efficiency of N retention despite constant or even reduced N inputs. We have quantified long-term changes in N inputs (atmospheric deposition, imported food and agricultural fertilizers), outputs (N concentration and export) and retention in the urbanizing Lamprey River watershed in coastal NH. Overall, the Lamprey watershed is 70% forested, receives about 13.5 kg N/ha/yr and has a high rate of annual N retention (85%). Atmospheric deposition (8.7 kg/ha/yr) is the largest N input to the watershed. Of the 2.2 kg N/ha/yr exported in the Lamprey River, dissolved organic N (DON) is the dominant form (50% of total) and it varies spatially throughout the watershed with wetland cover. Nitrate accounts for 30% of the N exported, shows a statistically significant increase from 1999 to 2009, and its spatial variability in both concentration and export is related to human population density. In sub-basins throughout the Lamprey, inorganic N retention is high (85-99%), but the efficiency of N retention declines sharply with increased human population density and associated anthropogenic N inputs. N assimilation in the vegetation, denitrification to the atmosphere and storage in the groundwater pool could all be important contributors to the current high rates of N retention. The temporal and spatial patterns that we have observed in nitrate concentration and export are driven by increases in N inputs and impervious surfaces over time, but the declining efficiency of N retention suggests that the watershed may also be reaching N saturation. The downstream receiving estuary, Great Bay, already suffers from low dissolved oxygen levels and eelgrass loss in part due to N loading from the Lamprey watershed. Targeting and reducing

On the persistence of polar domains in ultrathin ferroelectric capacitors

Czech Academy of Sciences Publication Activity Database

Zubko, P.; Lu, H.; Bark, C.-W.; Martí, Xavier; Santiso, J.; Eom, C.-B.; Catalan, G.; Gruverman, A.

2017-01-01

Roč. 29, č. 28 (2017), s. 1-8, č. článku 284001. ISSN 1361-648X R&D Projects: GA ČR GB14-37427G Institutional support: RVO:68378271 Keywords : ultrathin barium titanate * tunnel junctions * ferroelectric domains * polarization screening * retention * negative capacitance Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.)

Silicon quantum dots: surface matters

Czech Academy of Sciences Publication Activity Database

Dohnalová, K.; Gregorkiewicz, T.; Kůsová, Kateřina

2014-01-01

Roč. 26, č. 17 (2014), 1-28 ISSN 0953-8984 R&D Projects: GA ČR GPP204/12/P235 Institutional support: RVO:68378271 Keywords : silicon quantum dots * quantum dot * surface chemistry * quantum confinement Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.346, year: 2014

Pre-stimulus BOLD-network activation modulates EEG spectral activity during working memory retention

Directory of Open Access Journals (Sweden)

Mara eKottlow

2015-05-01

Full Text Available Working memory (WM processes depend on our momentary mental state and therefore exhibit considerable fluctuations. Here, we investigate the interplay of task-preparatory and task-related brain activity as represented by pre-stimulus BOLD-fluctuations and spectral EEG from the retention periods of a visual WM task. Visual WM is used to maintain sensory information in the brain enabling the performance of cognitive operations and is associated with mental health.We tested 22 subjects simultaneously with EEG and fMRI while performing a visuo-verbal Sternberg task with two different loads, allowing for the temporal separation of preparation, encoding, retention and retrieval periods.Four temporally coherent networks - the default mode network (DMN, the dorsal attention, the right and the left WM network - were extracted from the continuous BOLD data by means of a group ICA. Subsequently, the modulatory effect of these networks’ pre-stimulus activation upon retention-related EEG activity in the theta, alpha and beta frequencies was analyzed. The obtained results are informative in the context of state-dependent information processing.We were able to replicate two well-known load-dependent effects: the frontal-midline theta increase during the task and the decrease of pre-stimulus DMN activity. As our main finding, these two measures seem to depend on each other as the significant negative correlations at frontal-midline channels suggested. Thus, suppressed pre-stimulus DMN levels facilitated later task related frontal midline theta increases. In general, based on previous findings that neuronal coupling in different frequency bands may underlie distinct functions in WM retention, our results suggest that processes reflected by spectral oscillations during retention seem not only to be online synchronized with activity in different attention-related networks but are also modulated by activity in these networks during preparation intervals.

Bromatological composition and dry matter digestibility of millet cultivars subjected to nitrogen doses

Directory of Open Access Journals (Sweden)

W.H.D. Buso

2014-06-01

Full Text Available The bromatological composition and in vitro dry matter digestibility of millet cultivars were assessed for different nitrogen doses and two sowing seasons in the Ceres municipality of Goiás state, Brazil. The treatments consisted of three millet cultivars (ADR-7010, ADR-500 and BRS-1501, four nitrogen (N doses (0, 50, 100 and 200kg ha-1 of N and two sowing seasons. Three replicates and a randomised block design with a 3 x 4 x 2 factorial scheme were used. Two cuttings were performed in each season when plants reached an average height of 0.70 cm. No significant interactions were observed between or among cultivars for N doses and dry matter (DM, crude protein (CP, neutral detergent fibre (NDF and acid detergent fibre (ADF contents. The DM, CP, NDF and ADF contents were significantly different between N doses. The DM and CP contents increased as the N dose increased to 100kg ha-1. The maximum DM and CP contents were 11.14 and 22.53%, respectively. The NDF and ADF contents were higher in the control treatment (60.11 and 30.01%, respectively. In addition, the lowest ADF and NDF concentrations occurred at an N dose of 50kg ha-1 (56.33 and 30.23%, respectively. The DM contents were higher for the February sowing, with an average of 10.59%. The highest CP and ADF contents were found for the December sowing (22.46 and 31.58%, respectively. No significant differences were found for millet cultivars, N doses or sowing seasons. A significant interaction was found between sowing season and millet cultivar. The BRS-1501 cultivar had a higher in vitro dry matter digestibility in the December/2010 sowing (73.88%.

A strategic approach to employee retention.

Science.gov (United States)

Gering, John; Conner, John

2002-11-01

A sound retention strategy should incorporate a business plan, a value proposition, progress measures, and management influences. The business plan will indicate whether a healthcare organization will achieve a return on investment for its effort. A value proposition will showcase an organization's strengths and differentiate it from its competitors. Measuring progress toward meeting retention goals at regular intervals will help keep an organization on track. The best managers require accountability, rewarding employees for their successes and taking corrective action as necessary. Retention rate targets must be at a level that will achieve a competitive advantage in the served market.

Frontal white matter hyperintensities, clasmatodendrosis and gliovascular abnormalities in ageing and post-stroke dementia.

Science.gov (United States)

Chen, Aiqing; Akinyemi, Rufus O; Hase, Yoshiki; Firbank, Michael J; Ndung'u, Michael N; Foster, Vincent; Craggs, Lucy J L; Washida, Kazuo; Okamoto, Yoko; Thomas, Alan J; Polvikoski, Tuomo M; Allan, Louise M; Oakley, Arthur E; O'Brien, John T; Horsburgh, Karen; Ihara, Masafumi; Kalaria, Raj N

2016-01-01

White matter hyperintensities as seen on brain T2-weighted magnetic resonance imaging are associated with varying degrees of cognitive dysfunction in stroke, cerebral small vessel disease and dementia. The pathophysiological mechanisms within the white matter accounting for cognitive dysfunction remain unclear. With the hypothesis that gliovascular interactions are impaired in subjects with high burdens of white matter hyperintensities, we performed clinicopathological studies in post-stroke survivors, who had exhibited greater frontal white matter hyperintensities volumes that predicted shorter time to dementia onset. Histopathological methods were used to identify substrates in the white matter that would distinguish post-stroke demented from post-stroke non-demented subjects. We focused on the reactive cell marker glial fibrillary acidic protein (GFAP) to study the incidence and location of clasmatodendrosis, a morphological attribute of irreversibly injured astrocytes. In contrast to normal appearing GFAP+ astrocytes, clasmatodendrocytes were swollen and had vacuolated cell bodies. Other markers such as aldehyde dehydrogenase 1 family, member L1 (ALDH1L1) showed cytoplasmic disintegration of the astrocytes. Total GFAP+ cells in both the frontal and temporal white matter were not greater in post-stroke demented versus post-stroke non-demented subjects. However, the percentage of clasmatodendrocytes was increased by >2-fold in subjects with post-stroke demented compared to post-stroke non-demented subjects (P = 0.026) and by 11-fold in older controls versus young controls (P < 0.023) in the frontal white matter. High ratios of clasmotodendrocytes to total astrocytes in the frontal white matter were consistent with lower Mini-Mental State Examination and the revised Cambridge Cognition Examination scores in post-stroke demented subjects. Double immunofluorescent staining showed aberrant co-localization of aquaporin 4 (AQP4) in retracted GFAP+ astrocytes with

Dynamic behaviour of river colloidal and dissolved organic matter through cross-flow ultrafiltration system.

Science.gov (United States)

Wilding, Andrew; Liu, Ruixia; Zhou, John L

2005-07-01

Through cross-flow filtration (CFF) with a 1-kDa regenerated cellulose Pellicon 2 module, the ultrafiltration characteristics of river organic matter from Longford Stream, UK, were investigated. The concentration of organic carbon (OC) in the retentate in the Longford Stream samples increased substantially with the concentration factor (cf), reaching approximately 40 mg/L at cf 15. The results of dissolved organic carbon (DOC) and colloidal organic carbon (COC) analysis, tracking the isolation of colloids from river waters, show that 2 mg/L of COC was present in those samples and good OC mass balance (77-101%) was achieved. Fluorescence measurements were carried out for the investigation of retentate and permeate behaviour of coloured dissolved organic materials (CDOM). The concentrations of CDOM in both the retentate and permeate increased with increasing cf, although CDOM were significantly more concentrated in the retentate. The permeation model expressing the correlation between log[CDOM] in the permeate and logcf was able to describe the permeation behaviour of CDOM in the river water with regression coefficients (r(2)) of 0.94 and 0.98. Dry weight analysis indicated that the levels of organic colloidal particles were from 49 to 71%, and between 29 and 51% of colloidal particles present were inorganic. COC as a percentage of DOC was found to be 10-16% for Longford Stream samples.

The Retention of Female Unrestricted Line Officers

National Research Council Canada - National Science Library

Pecenco, Elena G

2005-01-01

This thesis analyzes the retention of female Naval officers, focusing on the relationship between officer selection metrics and retention beyond minimum service obligation and the effect of lateral...

12 CFR 609.945 - Records retention.

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Records retention. 609.945 Section 609.945 Banks and Banking FARM CREDIT ADMINISTRATION FARM CREDIT SYSTEM ELECTRONIC COMMERCE Standards for Boards and Management § 609.945 Records retention. Records stored electronically must be accurate, accessible...

Employee Retention Strategies And Organizational Performance ...

African Journals Online (AJOL)

Implication of the results for practice is that any organization that fails to put in place adequate employee retention strategies is not likely to retain competent and motivated workforce in its employment and hence experience frequent labour turnover and poor organizational performance. Keywords: Employees, Retention ...

African Retentions in Blues and Jazz.

Science.gov (United States)

Meadows, Eddie S.

1979-01-01

The perseverance of African musical characteristics among American Blacks is an historic reality. African retentions have been recorded in Black music of the antebellum period. Various African scales and rhythms permeate Black American music today as evidenced in the retentions found in blues and jazz. (RLV)

Emotional Intelligence and Nursing Student Retention

Science.gov (United States)

Wilson, Victoria Jane

2013-01-01

The study examined the constructs of a Multi-Intelligence Model of Retention with four constructs: cognitive and emotional-social intelligence, student characteristics, and environmental factors. Data were obtained from sophomore students entering two diploma, nine associate, and five baccalaureate nursing programs. One year later, retention and…

Correlates of long-term alkaline earth retention

International Nuclear Information System (INIS)

Stebbings, J.H.; Schlenker, R.A.; Keane, A.T.; Kotek, T.J.; Jansen, A.J.

1987-01-01

Data on 63 subjects from several occupational cohorts, plus iatrogenic subjects, were analyzed to determine effects of sex, age at exposure, exposure duration, and age at measurement upon the coefficient of elimination (λ, % y -1 ). While 12 women exposed at age 17-18 had λ's significantly lower than those exposed at ages 15-16 or 21-26, λ showed no overall trend with age at exposure among females. Higher radium burdens associated with bone damage are associated with decreased λ's, but neither exposure duration nor age at measurement correlated significantly with λ. The 12 males had λ's about 60% of those for females after adjustment for retention time. The males λ's were lower the earlier the age at exposure. Effects of personal habits were studied in a homogeneous cohort of female Illinois dial painters with relatively uniform ages at first employment. The most powerful predictor of radium loss was the number of cups of coffee and tea consumed per day. Coffee/tea consumption explained ∼ 35% of the variance in λ, the effect persisting after deletion of smokers and subjects with x-ray evidence of bone damage. Higher weight/height ratios were associated with higher λ's. Individuals smoking throughout the measurement period had significantly low λ's. A complex interaction of weight/height ratios to both smoking and radium-induced bone damage was observed

Urinary Retention

Science.gov (United States)

... 2011. [4] Mevcha A, Drake MJ. Etiology and management of urinary retention in women. Indian Journal of Urology. 2010;26(2):230–235. August ... 30 a.m. to 5 p.m. eastern time, M-F Follow Us NIH… Turning Discovery Into ... Disease Urologic Diseases Endocrine Diseases Diet & Nutrition ...

Retention of airborne particles in granular bed filters

International Nuclear Information System (INIS)

Stroem, L.

1981-01-01

A literature survey was made on theoretical models for the prediction of particle retention in sand beds. Also data on observed retention was collected from the literature. Based on this information, a semi-empirical model was compiled. Comparison of the model with published retention data shows a general agreement. (Auth.)

Genetic Schizophrenia Risk Variants Jointly Modulate Total Brain and White Matter Volume

DEFF Research Database (Denmark)

Terwisscha van Scheltinga, Afke F; Bakker, Steven C; van Haren, Neeltje E M

2013-01-01

with total brain volume (R(2)=.048, p=1.6×10(-4)) and white matter volume (R(2)=.051, p=8.6×10(-5)) equally in patients and control subjects. The number of (independent) SNPs that substantially influenced both disease risk and white matter (n=2020) was much smaller than the entire set of SNPs that modulated...... modulating schizophrenia and brain volume. METHODS: Odds ratios for genome-wide SNP data were calculated in the sample collected by the Psychiatric Genome-wide Association Study Consortium (8690 schizophrenia patients and 11,831 control subjects, excluding subjects from the present study). These were used...

Measurement of the Retention Time of Different Ophthalmic Formulations with Ultrahigh-Resolution Optical Coherence Tomography.

Science.gov (United States)

Gagliano, Caterina; Papa, Vincenzo; Amato, Roberta; Malaguarnera, Giulia; Avitabile, Teresio

2018-04-01

Purpose/aim of the study: The purpose of this study was to measure the pre-corneal retention time of two marketed formulations (eye drops and eye gel) of a steroid-antibiotic fixed combination (FC) containing 0.1% dexamethasone and 0.3% netilmicin. Pre-corneal retention time was evaluated in 16 healthy subjects using an ultrahigh-resolution anterior segment spectral domain optical coherence tomography (OCT). All subjects randomly received both formulations of the FC (Netildex, SIFI, Italy). Central tear film thickness (CTFT) was measured before instillation (time 0) and then after 1, 10, 20, 30, 40 50, 60 and 120 min. The pre-corneal retention time was calculated by plotting CTFT as a function of time. Differences between time points and groups were analyzed by Student's t-test. CTFT increased significantly after the instillation of the eye gel formulation (p < 0.001). CTFT reached its maximum value 1 min after instillation and returned to baseline after 60 min. No effect on CTFT was observed after the instillation of eye drops. The difference between the two formulations was statistically significant at time 1 min (p < 0.0001), 10 min (p < 0.001) and 20 min (p < 0.01). The FC formulated as eye gel was retained on the ocular surface longer than the corresponding eye drop solution. Consequently, the use of the eye gel might extend the interval between instillations and decrease the frequency of administration.

Soil retention of hexavalent chromium released from construction and demolition waste in a road-base-application scenario.

Science.gov (United States)

Butera, Stefania; Trapp, Stefan; Astrup, Thomas F; Christensen, Thomas H

2015-11-15

We investigated the retention of Cr(VI) in three subsoils with low organic matter content in laboratory experiments at concentration levels relevant to represent leachates from construction and demolition waste (C&DW) reused as unbound material in road construction. The retention mechanism appeared to be reduction and subsequent precipitation as Cr(III) on the soil. The reduction process was slow and in several experiments it was still proceeding at the end of the six-month experimental period. The overall retention reaction fit well with a second-order reaction governed by actual Cr(VI) concentration and reduction capacity of the soil. The experimentally determined reduction capacities and second-order kinetic parameters were used to model, for a 100-year period, the one-dimensional migration of Cr(VI) in the subsoil under a layer of C&DW. The resulting Cr(VI) concentration would be negligible below 7-70 cm depth. However, in rigid climates and with high water infiltration through the road pavement, the reduction reaction could be so slow that Cr(VI) might migrate as deep as 200 cm under the road. The reaction parameters and the model can form the basis for systematically assessing under which scenarios Cr(VI) from C&DW could lead to an environmental issue for ground- and receiving surface waters. Copyright © 2015 Elsevier B.V. All rights reserved.

Black Student Retention in Higher Education.

Science.gov (United States)

Lang, Marvel, Ed.; Ford, Clinita A., Ed.

This collection focuses on problems in the recruitment, enrollment and retention of Blacks in higher education in America. The following chapters are provided: "The Black Student Retention Problem in Higher Education: Some Introductory Perspectives" (Marvel Lang); "Early Acceptance and Institutional Linkages in a Model Program of Recruitment,…

Minority Teacher Recruitment and Retention Strategies

Science.gov (United States)

Kearney-Gissendaner, Janet E.

2010-01-01

The tools and resources in this book help school leaders seamlessly incorporate minority teacher recruitment and retention programs into current human-resources activities. With details about exemplary minority teacher recruitment and retention programs, this book also showcases strategies for how to replicate such programs in your own school or…

Patterns of brain structural connectivity differentiate normal weight from overweight subjects

Directory of Open Access Journals (Sweden)

Arpana Gupta

2015-01-01

Conclusions: 1. An increased BMI (i.e., overweight subjects is associated with distinct changes in gray-matter and fiber density of the brain. 2. Classification algorithms based on white-matter connectivity involving regions of the reward and associated networks can identify specific targets for mechanistic studies and future drug development aimed at abnormal ingestive behavior and in overweight/obesity.

No Enhancement of 24-Hour Visuomotor Skill Retention by Post-Practice Caffeine Administration.

Directory of Open Access Journals (Sweden)

Sara J Hussain

Full Text Available Caffeine is widely consumed throughout the world and appears to indirectly facilitate learning and memory through effects on attention and motivation. Animal work indicates that post-training caffeine administration augments inhibitory avoidance memory, spatial memory, and object memory. In humans, post-training caffeine administration enhances the ability to discern between familiar images and new, similar images. However, the effect of post-training caffeine administration on motor memory has not been examined. Therefore, we tested two groups of low caffeine consumers (average weekly consumption ≤500 mg in a double-blind, placebo-controlled study involving acquisition of a continuous isometric visuomotor tracking skill. On Day 1, subjects completed 5 blocks (150 repetitions of training on the continuous isometric visuomotor skill and subsequently ingested either 200 mg of caffeine or placebo. On day 2, subjects completed an additional 5 blocks of training. Day 1 mean performance and performance variability were both similar between groups, suggesting that both groups acquired the motor skill similarly. For mean performance on Day 2, patterns of re-learning, mean performance learning magnitudes, mean performance learning rates, and mean performance retention magnitudes were all similar between groups. For performance variability on Day 2, there was a small trend towards increased variability in the caffeine group during re-learning, but performance variability learning magnitudes and performance variability retention magnitudes did not differ between groups. Because motor skill acquisition can also be conceptualized as a reduction in performance variability, these results suggest that there may be a small negative effect of post-practice caffeine administration on memory of a newly-learned visuomotor skill. Overall, we found no evidence to suggest that post-training caffeine administration enhances 24-hour retention of a newly

No Enhancement of 24-Hour Visuomotor Skill Retention by Post-Practice Caffeine Administration.

Science.gov (United States)

Hussain, Sara J; Cole, Kelly J

2015-01-01

Caffeine is widely consumed throughout the world and appears to indirectly facilitate learning and memory through effects on attention and motivation. Animal work indicates that post-training caffeine administration augments inhibitory avoidance memory, spatial memory, and object memory. In humans, post-training caffeine administration enhances the ability to discern between familiar images and new, similar images. However, the effect of post-training caffeine administration on motor memory has not been examined. Therefore, we tested two groups of low caffeine consumers (average weekly consumption ≤500 mg) in a double-blind, placebo-controlled study involving acquisition of a continuous isometric visuomotor tracking skill. On Day 1, subjects completed 5 blocks (150 repetitions) of training on the continuous isometric visuomotor skill and subsequently ingested either 200 mg of caffeine or placebo. On day 2, subjects completed an additional 5 blocks of training. Day 1 mean performance and performance variability were both similar between groups, suggesting that both groups acquired the motor skill similarly. For mean performance on Day 2, patterns of re-learning, mean performance learning magnitudes, mean performance learning rates, and mean performance retention magnitudes were all similar between groups. For performance variability on Day 2, there was a small trend towards increased variability in the caffeine group during re-learning, but performance variability learning magnitudes and performance variability retention magnitudes did not differ between groups. Because motor skill acquisition can also be conceptualized as a reduction in performance variability, these results suggest that there may be a small negative effect of post-practice caffeine administration on memory of a newly-learned visuomotor skill. Overall, we found no evidence to suggest that post-training caffeine administration enhances 24-hour retention of a newly-learned continuous visuomotor

No Enhancement of 24-Hour Visuomotor Skill Retention by Post-Practice Caffeine Administration

Science.gov (United States)

Hussain, Sara J.; Cole, Kelly J.

2015-01-01

Caffeine is widely consumed throughout the world and appears to indirectly facilitate learning and memory through effects on attention and motivation. Animal work indicates that post-training caffeine administration augments inhibitory avoidance memory, spatial memory, and object memory. In humans, post-training caffeine administration enhances the ability to discern between familiar images and new, similar images. However, the effect of post-training caffeine administration on motor memory has not been examined. Therefore, we tested two groups of low caffeine consumers (average weekly consumption ≤500 mg) in a double-blind, placebo-controlled study involving acquisition of a continuous isometric visuomotor tracking skill. On Day 1, subjects completed 5 blocks (150 repetitions) of training on the continuous isometric visuomotor skill and subsequently ingested either 200 mg of caffeine or placebo. On day 2, subjects completed an additional 5 blocks of training. Day 1 mean performance and performance variability were both similar between groups, suggesting that both groups acquired the motor skill similarly. For mean performance on Day 2, patterns of re-learning, mean performance learning magnitudes, mean performance learning rates, and mean performance retention magnitudes were all similar between groups. For performance variability on Day 2, there was a small trend towards increased variability in the caffeine group during re-learning, but performance variability learning magnitudes and performance variability retention magnitudes did not differ between groups. Because motor skill acquisition can also be conceptualized as a reduction in performance variability, these results suggest that there may be a small negative effect of post-practice caffeine administration on memory of a newly-learned visuomotor skill. Overall, we found no evidence to suggest that post-training caffeine administration enhances 24-hour retention of a newly-learned continuous visuomotor

Removal versus retention of cerclage in preterm premature rupture of membranes: a randomized controlled trial.

Science.gov (United States)

Galyean, Anna; Garite, Thomas J; Maurel, Kimberly; Abril, Diana; Adair, Charles D; Browne, Paul; Combs, C Andrew; How, Helen; Iriye, Brian K; Kominiarek, Michelle; Lu, George; Luthy, David; Miller, Hugh; Nageotte, Michael; Ozcan, Tulin; Porto, Manuel; Ramirez, Mildred; Sawai, Shirley; Sorokin, Yoram

2014-10-01

The decision of whether to retain or remove a previously placed cervical cerclage in women who subsequently rupture fetal membranes in a premature gestation is controversial and all studies to date are retrospective. We performed a multicenter randomized controlled trial of removal vs retention of cerclage in these patients to determine whether leaving the cerclage in place prolonged gestation and/or increased the risk of maternal or fetal infection. A prospective randomized multicenter trial of 27 hospitals was performed. Patients included were those with cerclage placement at ≤23 weeks 6 days in singleton or twin pregnancies, with subsequent spontaneous rupture of membranes between 22 weeks 0 days and 32 weeks 6 days. Patients were randomized to retention or removal of cerclage. Patients were then expectantly managed and delivered only for evidence of labor, chorioamnionitis, fetal distress, or other medical or obstetrical indications. Management after 34 weeks was at the clinician's discretion. The initial sample size calculation determined that a total of 142 patients should be included but after a second interim analysis, futility calculations determined that the conditional power for showing statistical significance after randomizing 142 patients for the primary outcome of prolonging pregnancy was 22.8%. Thus the study was terminated after a total of 56 subjects were randomized with complete data available for analysis, 32 to removal and 24 to retention of cerclage. There was no statistical significance in primary outcome of prolonging pregnancy by 1 week comparing the 2 groups (removal 18/32, 56.3%; retention 11/24, 45.8%) P = .59; or chorioamnionitis (removal 8/32, 25.0%; retention 10/24, 41.7%) P = .25, respectively. There was no statistical difference in composite neonatal outcomes (removal 16/33, 50%; retention 17/30, 56%), fetal/neonatal death (removal 4/33, 12%; retention 5/30, 16%); or gestational age at delivery (removal mean 200 days; retention

White matter abnormalities of microstructure and physiological noise in schizophrenia

OpenAIRE

Cheng, Hu; Newman, Sharlene D.; Kent, Jerillyn S.; Bolbecker, Amanda; Klaunig, Mallory J.; O'Donnell, Brian F.; Puce, Aina; Hetrick, William P.

2015-01-01

White matter abnormalities in schizophrenia have been revealed by many imaging techniques and analysis methods. One of the findings by diffusion tensor imaging is a decrease in fractional anisotropy (FA), which is an indicator of white matter integrity. On the other hand, elevation of metabolic rate in white matter was observed from positron emission tomography (PET) studies. In this report, we aim to compare the two structural and functional effects on the same subjects. Our comparison is ba...

76 FR 34010 - Credit Risk Retention

Science.gov (United States)

2011-06-10

... 2501-AD53 Credit Risk Retention AGENCIES: Office of the Comptroller of the Currency, Treasury (OCC... credit risk retention requirements of section 15G of the Securities Exchange Act of 1934, as added by the Dodd-Frank Wall Street Reform and Consumer Protection Act (``Credit Risk NPR'' or ``proposed rule...

Affairs of State and Student Retention: An Exploratory Study of the Factors that Impact Student Retention in a Politically Turbulent Region

Science.gov (United States)

Ben-Tsur, Dalia

2007-01-01

This study examines the impact of a country's security unrest on student retention. It draws on the key factors that influence retention worldwide, adopts Bourdieu's notion of cultural capital and also brings in concepts related to terrorism and security unrest traditionally absent from theories on student retention. Based on a case study carried…

A comparative evaluation of the effect of dentin desensitizers on the retention of complete cast metal crowns

Directory of Open Access Journals (Sweden)

Saili M Chandavarkar

2015-01-01

Full Text Available Context: Desensitizers are used to reduce dentin hypersensitivity. They affect the surface texture of prepared dentin and may alter the retention of fixed restorations. Aims: The aim was to evaluate the effect of dentin desensitizers on the retention of complete cast metal crowns luted with glass ionomer cement. Subjects and Methods: Fifty freshly extracted human premolars were subjected to standardized tooth preparation (20° total convergence, 4 mm axial height with a computer numerically controlled machine. Individual cast metal crowns were fabricated from a base metal alloy. Dentin desensitizers included none (control, a glutaraldehyde (GLU based primer (Gluma desensitizer, casein phosphopeptide (CPP-amorphous calcium phosphate (ACP (GC Mousse, erbium, chromium: YSGG laser (Waterlase MD Turbo, Biolase and Pro-Argin (Colgate Sensitive Pro-Relief desensitizing polishing paste. After desensitization, crowns were luted with glass ionomer cement and kept for 48 h at 37°C in 100% relative humidity. The samples were tested using a universal testing machine by applying a load at a crosshead speed of 0.5 mm/min. Statistical Analysis Used: Statistical analysis included One-way ANOVA, followed by the Scheffe post-hoc test with P < 0.05. Results: All dentin desensitizers showed significantly different values: Pro-Argin (4.10 Megapascals [Mpa] < CPP-ACP (4.01 mpa < GLU based primer (3.87 Mpa < Virgin dentin (3.65 Mpa < LASER (3.37 Mpa. Conclusions : On comparing the effect of prepared virgin dentin, GLU based primer, CPP-ACP, LASER and Pro-Argin on the retention of complete cast metal crowns luted with glass ionomer cement on prepared teeth, it can be concluded that Pro-Argin and CPP-ACP showed the best retention in this in vitro study.

Natural organic matter to enhance electrokinetic transport of PAH

Energy Technology Data Exchange (ETDEWEB)

Suer, P.; Joensson, S.; Allard, B. [Man-Technology-Environment Research Centre, Oerebro Univ. (Sweden)

2001-07-01

The remediation of contaminated soil can be enhanced with natural organic matter (NOM) as a complexing agent for pollutants. NOM has both hydrophobic and acidic properties, so that it is charged and thus subject to electroremediation. At the same time many contaminants have a high affinity for organic matter. Organic matter was produced in situ in an electric field or added in solute form. The resulting dissolved organic matter was transported towards the cathode, probably by cationic colloids. Produced dissolved organic matter included high molecular weight molecules near the cathode, at the site of pH buffering. Pyrene and phenanthrene were likewise transported towards the cathode. Movement was small but distinctive in 2-day experiments. Clay influence the soil/water distribution of the PAH but no effect on the total transport could be discerned. The presence of solid organic matter in the soil removed all PAH from the water phase, even though the concentration of organic matter in the water phase was high as well. (orig.)

Long-term clearance from small airways in subjects with ciliary dysfunction

Directory of Open Access Journals (Sweden)

Hjelte Lena

2006-05-01

Full Text Available Abstract The objective of this study was to investigate if long-term clearance from small airways is dependent on normal ciliary function. Six young adults with primary ciliary dyskinesia (PCD inhaled 111 Indium labelled Teflon particles of 4.2 μm geometric and 6.2 μm aerodynamic diameter with an extremely slow inhalation flow, 0.05 L/s. The inhalation method deposits particles mainly in the small conducting airways. Lung retention was measured immediately after inhalation and at four occasions up to 21 days after inhalation. Results were compared with data from ten healthy controls. For additional comparison three of the PCD subjects also inhaled the test particles with normal inhalation flow, 0.5 L/s, providing a more central deposition. The lung retention at 24 h in % of lung deposition (Ret24 was higher (p 24 with slow inhalation flow was 73.9 ± 1.9 % compared to 68.9 ± 7.5 % with normal inhalation flow in the three PCD subjects exposed twice. During day 7–21 the three PCD subjects exposed twice cleared 9 % with normal flow, probably representing predominantly alveolar clearance, compared to 19 % with slow inhalation flow, probably representing mainly small airway clearance. This study shows that despite ciliary dysfunction, clearance continues in the small airways beyond 24 h. There are apparently additional clearance mechanisms present in the small airways.

Corrosion behavior of dental alloys used for retention elements in prosthodontics.

Science.gov (United States)

Nierlich, Judith; Papageorgiou, Spyridon N; Bourauel, Christoph; Hültenschmidt, Robert; Bayer, Stefan; Stark, Helmut; Keilig, Ludger

2016-06-01

The purpose of this study was to investigate the corrosion behavior of 10 different high noble gold-based dental alloys, used for prosthodontic retention elements, according to ISO 10271. Samples of 10 high-noble and noble gold-based dental alloys were subjected to: (i) static immersion tests with subsequent analysis of ion release for eight different elements using mass spectrometry; (ii) electrochemical tests, including open-circuit potential and potentiodynamic scans; and (iii) scanning electron microscopy, followed by energy-dispersive X-ray microscopy. The results were analyzed using one-way ANOVA and Sidak multiple-comparisons post-hoc test at a level of significance of α = 0.05. Significant differences were found among the 10 alloys studied for all ions (P alloys. Scanning electron microscopy analysis confirmed the existence of typically small-diameter corrosion defects, whilst the energy-dispersive X-ray analysis found no significant alteration in the elemental composition of the alloys. The results of this study reveal the variability in the corrosive resistance among the materials used for retention elements in prosthodontics. © 2016 Eur J Oral Sci.

Employee retention within the Information Technology Division of a South African Bank

Directory of Open Access Journals (Sweden)

Joy Mohlala

2012-05-01

Research purpose: To understand the challenges faced by the bank’s information technology leadership team to retain employees. Motivation for the study: To understand the challenges faced in attracting and retaining information technology professionals, and how this can serve as input for reducing skills shortages in Information Technology Divisions. Research design, approach and method: An interpretive approach employing a case study strategy and qualitative methods was employed. Semi structured interviews were conducted with thirteen senior managers and four directors of the bank’s Information Technology Division, who were selected on a purposive basis. Data were subjected to Creswell’s four stage data analysis process. Main findings: Findings indicate that employee turnover is the main contributor of skills shortages within the studied division. The lack of a retention strategy is making it difficult for leadership to identify crucial skills that must be retained. Practical/managerial implications: Evidence suggests that this bank, although they would like to retain information technology professionals, is not creating an environment conducive to do this, as little attention is paid to the unique demands of this group of employees. Contribution/value-add: This study investigates a specific group of employees for which a unique retention strategy does not exist. In understanding the challenges that impact on attracting and retaining information technology professionals, this study can contribute to the development of a retention strategy for these employees.

Executive dysfunctions in migraine with and without aura: what is the role of white matter lesions?

Science.gov (United States)

Le Pira, Francesco; Reggio, Ester; Quattrocchi, Graziella; Sanfilippo, Cristina; Maci, Tiziana; Cavallaro, Tiziana; Zappia, Mario

2014-01-01

Executive dysfunctions and white matter lesions on magnetic resonance imaging have been reported in migraine. The aim of this study was to determine whether any correlation between these 2 variables exists. Forty-four subjects affected by migraine with or without aura were compared with 16 healthy subjects. A battery of neuropsychological tests assessing executive functions was administered to all subjects. Number and total volume of white matter lesions were assessed in the whole brain and in the frontal lobe. The performances of both groups of migraineurs, with and without aura, were significantly worse when compared with controls on Boston Scanning Test. Moreover, we found lower performances compared with controls respectively on Frontal Assessment Battery in patients with migraine with aura and on Controlled Oral Word Association Test in patients with migraine without aura. Nineteen patients (43.2%) and one control subject (6.2%) had white matter lesions. We did not find any significant correlation between white matter lesions load and neuropsychological performances. On the basis of our results, white matter lesions load on magnetic resonance imaging do not seem to contribute to neuropsychological performances deficit in migraineurs. © 2013 American Headache Society.

Phosphorus in the feeding of pigs : effect of diet on the absorption and retention of phosphorus by growing pigs

NARCIS (Netherlands)

Jongbloed, A.W.

1987-01-01

An extensive review is given of the literature concerning phosphorus feeding of pigs. Subjects dealt with are: 1. physiological background, regulation and effect of diet composition and nutrient supply on phosphorus absorption and retention; 2. estimation of the amount of P present in the

A Model for Freshman Engineering Retention

Science.gov (United States)

Veenstra, Cindy P.; Dey, Eric L.; Herrin, Gary D.

2009-01-01

With the current concern over the growing need for more engineers, there is an immediate need to improve freshman engineering retention. A working model for freshman engineering retention is needed. This paper proposes such a model based on Tinto's Interactionalist Theory. Emphasis in this model is placed on pre-college characteristics as…

Retention of Content Utilizing a Flipped Classroom Approach.

Science.gov (United States)

Shatto, Bobbi; LʼEcuyer, Kristine; Quinn, Jerod

The flipped classroom experience promotes retention and accountability for learning. The authors report their evaluation of a flipped classroom for accelerated second-degree nursing students during their primary medical-surgical nursing course. Standardized HESI® scores were compared between a group of students who experienced the flipped classroom and a previous group who had traditional teaching methods. Short- and long-term retention was measured using standardized exams 3 months and 12 months following the course. Results indicated that short-term retention was greater and long- term retention was significantly great in the students who were taught using flipped classroom methodology.

The value of animations in biology teaching: a study of long-term memory retention.

Science.gov (United States)

O'Day, Danton H

2007-01-01

Previous work has established that a narrated animation is more effective at communicating a complex biological process (signal transduction) than the equivalent graphic with figure legend. To my knowledge, no study has been done in any subject area on the effectiveness of animations versus graphics in the long-term retention of information, a primary and critical issue in studies of teaching and learning. In this study, involving 393 student responses, three different animations and two graphics-one with and one lacking a legend-were used to determine the long-term retention of information. The results show that students retain more information 21 d after viewing an animation without narration compared with an equivalent graphic whether or not that graphic had a legend. Students' comments provide additional insight into the value of animations in the pedagogical process, and suggestions for future work are proposed.

Determining the Chemical and Biological Availability of Zinc in Urban Stormwater Retention Ponds

Science.gov (United States)

Camponelli, K.; Casey, R.; Lev, S. M.; Landa, E. R.; Snodgrass, J.

2005-12-01

Highway runoff has the potential to negatively impact receiving systems due to transport of contaminants that accumulate on road surfaces. Metals such as copper and zinc are major components of automobile brake pads and tires, respectively. As these automobile parts are degraded, these metal containing particulates are deposited on the roadway and are washed into storm water retention ponds and surface water bodies during precipitation events. It has been estimated that 15 to 60% of the Zn in urban stormwater runoff comes from tire wear and that tire wear is a significant source of Zn to the environment with release inventories comparable to waste incineration sources. In urban and sub-urban systems, this large source of Zn can accumulate in stormwater retention ponds which serve as habitat for a variety of species. Understanding the chemical and biological availability of Zn to biota is integral to assessing the habitat quality of retention ponds. This study is a first effort to relate the amount and speciation of Zn in a retention pond to Zn inputs through highway-derived runoff events. In addition, results suggest that the chemical speciation and availability of particulate Zn can be related to the bioavailability and toxicity of Zn to pond organisms (i.e. larval amphibians). The study site in Owings Mills, MD is located next to a four-lane highway from which it receives runoff through a single culvert. Five species of anurans are known to utilize the pond as a breeding site and Zn in amphibian tissues and retention pond sediments were highly elevated at this site in 2001 and 2002. A recent analysis of pond sediments, soils, roadway dust and storm water collected at this site suggests that roadway particulate matter transported during runoff events is the dominant source of Zn in this system. Overall, Zn and other trace metals were found to be most abundant in the clay sized faction of pond sediments and soils. The pond cores were found to have higher Zn and Cu

Mucous retention cyst of the maxillary sinus.

Science.gov (United States)

Ruprecht, A; Batniji, S; el-Neweihi, E

1986-12-01

The mucous retention cyst is not a rare phenomenon. The incidence of dental patients was determined. Of 1685 patient radiographs reviewed, 44 (2.6%) had one or more mucous retention cysts in the maxillary sinuses.

Transport and retention of biochar nanoparticles in a paddy soil under environmentally-relevant solution chemistry conditions.

Science.gov (United States)

Chen, Ming; Wang, Dengjun; Yang, Fan; Xu, Xiaoyun; Xu, Nan; Cao, Xinde

2017-11-01

Land application of biochar has been increasingly recommended as a powerful strategy for carbon sequestration and soil remediation. However, the biochar particles, especially those in the nanoscale range, may migrate or carry the inherent contaminants along the soil profile, posing a potential risk to the groundwater. This study investigated the transport and retention of wood chip-derived biochar nanoparticles (NPs) in water-saturated columns packed with a paddy soil. The environmentally-relevant soil solution chemistry including ionic strength (0.10-50 mM), electrolyte type (NaCl and CaCl 2 ), and natural organic matter (0-10 mg L -1 humic acid) were tested to elucidate their effects on the biochar NPs transport. Higher mobility of biochar NPs was observed in the soil at lower ionic strengths, with CaCl 2 electrolyte being more effective than NaCl in decreasing biochar NPs transport. The retained biochar NPs in NaCl was re-entrained (∼57.7%) upon lowering transient pore-water ionic strength, indicating that biochar NPs were reversibly retained in the secondary minimum. In contrast, negligible re-entrainment of biochar NPs occurred in CaCl 2 due to the primary minimum and/or particle aggregation. Humic acid increased the mobility of biochar NPs, likely due to enhanced electrosteric repulsive interactions. The transport behaviors of biochar NPs can be well interpreted by a two-site kinetic retention model that assumes reversible retention for one site, and irreversible retention for the other site. Our findings indicated that the transport of wood chip biochar NPs is significant in the paddy soil, highlighting the importance of understanding the mobility of biochar NPs in natural soils for accurately assessing their environmental impacts. Copyright © 2017 Elsevier Ltd. All rights reserved.

The influence of nutrient loading, climate and water depth on nitrogen and phosphorus loss in shallow lakes: a pan-European mesocosm experiment.

Czech Academy of Sciences Publication Activity Database

Coppens, J.; Hejzlar, Josef; Šorf, Michal; Jeppesen, E.; Erdogan, S.; Scharfenberger, U.; Mahdy, A.; Noges, P.; Tuvikene, A.; Blaho, D.L.; Trigal, C.; Papastergiadou, E.; Stefanidis, K.; Olsen, S.; Beklioglu, M.

2016-01-01

Roč. 778, č. 1 (2016), s. 13-32 ISSN 0018-8158 EU Projects: European Commission(XE) 244121 - REFRESH Institutional support: RVO:60077344 Keywords : nutrient retention * nutrient budget * shallow lake * organic matter * temperature Subject RIV: DA - Hydrology ; Limnology Impact factor: 2.056, year: 2016

Issues in subject recruitment and retention with pregnant and parenting substance-abusing women.

Science.gov (United States)

Howard, J; Beckwith, L

1996-01-01

To advance knowledge about the treatment of addiction among pregnant women and other women of childbearing age, investigators must adhere to the requirements of a strict experimental research design while concurrently providing clinical services. This means that researchers must address a variety of difficult questions, including the following: Was the sample large enough? Were the criteria for subject inclusion and exclusion well defined? Did the process of recruitment result in a sample that could be generalized to a larger population, or was the sample biased in some way? Was assignment to groups clearly random? What was the attrition rate? Was attrition the same in both experimental and comparison groups? Did baseline measures collect enough information to permit a description of the facts that were associated with attrition in each group? Was the attrition rate so high that the retained sample had special characteristics? If so, what were these features? This chapter highlights several problems related to these questions, describes the difficulties that investigators have faced in meeting clinical and research challenges to date, and suggests strategies for overcoming some obstacles. In establishing the Perinatal-20 project, the National Institute on Drug Abuse took an informed first step in organizing a substantial research effort to investigate treatment modalities that incorporate services specific to the needs of substance-abusing women who have children. This initial effort has resulted in a beginning knowledge base that can be used to refine and expand future treatment efforts. Even the issue of the "study unit" for this population is evolving. Today's researchers are attempting to determine whether the mother alone or the mother along with her dependent children constitutes the study unit. This question also has led professionals in the field to examine a range of specific outcome priorities, and investigators just now are beginning to determine exactly

Blood Pressure Directed Booster Trainings Improve Intensive Care Unit Provider Retention of Excellent Cardiopulmonary Resuscitation Skills.

Science.gov (United States)

Wolfe, Heather; Maltese, Matthew R; Niles, Dana E; Fischman, Elizabeth; Legkobitova, Veronika; Leffelman, Jessica; Berg, Robert A; Nadkarni, Vinay M; Sutton, Robert M

2015-11-01

Brief, intermittent cardiopulmonary resuscitation (CPR) training sessions, "Booster Trainings," improve CPR skill acquisition and short-term retention. The objective of this study was to incorporate arterial blood pressure (ABP) tracings into Booster Trainings to improve CPR skill retention. We hypothesized that ABP-directed CPR "Booster Trainings" would improve intensive care unit (ICU) provider 3-month retention of excellent CPR skills without need for interval retraining. A CPR manikin creating a realistic relationship between chest compression depth and ABP was used for training/testing. Thirty-six ICU providers were randomized to brief, bedside ABP-directed CPR manikin skill retrainings: (1) Booster Plus (ABP visible during training and testing) versus (2) Booster Alone (ABP visible only during training, not testing) versus (3) control (testing, no intervention). Subjects completed skill tests pretraining (baseline), immediately after training (acquisition), and then retention was assessed at 12 hours, 3 and 6 months. The primary outcome was retention of excellent CPR skills at 3 months. Excellent CPR was defined as systolic blood pressure of 100 mm Hg or higher and compression rate 100 to 120 per minute. Overall, 14 of 24 (58%) participants acquired excellent CPR skills after their initial training (Booster Plus 75% vs 50% Booster Alone, P = 0.21). Adjusted for age, ABP-trained providers were 5.2× more likely to perform excellent CPR after the initial training (95% confidence interval [95% CI], 1.3-21.2; P = 0.02), and to retain these skills at 12 hours (adjusted odds ratio, 4.4; 95% CI, 1.3-14.9; P = 0.018) and 3 months (adjusted odds ratio, 4.1; 95% CI, 1.2-13.9; P = 0.023) when compared to baseline performance. The ABP-directed CPR booster trainings improved ICU provider 3-month retention of excellent CPR skills without the need for interval retraining.

Quaternary herbicides retention by the amendment of acid soils with a bentonite-based waste from wineries.

Science.gov (United States)

Pateiro-Moure, M; Nóvoa-Muñoz, J C; Arias-Estévez, M; López-Periago, E; Martínez-Carballo, E; Simal-Gándara, J

2009-05-30

The agronomic utility of a solid waste, waste bentonite (WB), from wine companies was assessed. In this sense, the natural characteristics of the waste were measured, followed by the monitoring of its effects on the adsorption/desorption behaviour of three quaternary herbicides in acid soils after the addition of increasing levels of waste. This was done with the intention of studying the effect of the added organic matter on their adsorption. The high content in C (294 g kg(-1)), N (28 g kg(-1)), P (584 mg kg(-1)) and K (108 g kg(-1)) of WB turned it into an appropriate amendment to increase soil fertility, solving at the same time its disposal. WB also reduced the potential Cu phytotoxicity due to a change in Cu distribution towards less soluble fractions. The adsorption of the herbicides paraquat, diquat and difenzoquat by acid soils amended with different ratios of WB was measured. In all cases, Langmuir equation was fitted to the data. Paraquat (PQ) and diquat (DQ) were adsorbed and retained more strongly than difenzoquat (DFQ) in the acid soil studied. However, the lowest retention of DFQ in an acid soil can be increased by amendment with organic matter through a solid waste from wineries, and it is enough for duplicate retention a dosage rate of 10t/ha. Anyway, detritivores ecology can still be affected. Detritivores are the organisms that consume organic material, and in doing so contribute to decomposition and the recycling of nutrients. The term can also be applied to certain bottom-feeders in wet environments, which play a crucial role in benthic ecosystems, forming essential food chains and participating in the nitrogen cycle.

The influence of salivary variables on fluoride retention in dental plaque exposed to a mineral-enriching solution.

Science.gov (United States)

Kato, K; Nakagaki, H; Arai, K; Pearce, E I F

2002-01-01

This study was carried out to examine interindividual differences in salivary variables related to plaque accumulation and to estimate their influence on the fluoride retention in plaque in vivo by a mineral-enriching solution. Two saliva samples were taken from 10 subjects, once after brushing and once after 24 h without brushing. Calcium, phosphate and monofluorophosphatase (MFPase) activity in the saliva samples were determined. The salivary flow rate and the debris index were also recorded. After plaque had formed over 3 days within in situ plaque-generating devices, subjects were instructed to rinse with a mineral-enriching mouthrinse three times a day on 4 consecutive days. Plaque exposed to distilled water plus flavoring agents served as a control. Fluoride-free dentifrice was used during the experimental period. Twenty-four hours after the last rinsing, the samples were removed from the mouth, and fluoride and mineral distributions in plaque analyzed using a method previously reported by the authors. Salivary flow, MFPase activity and calcium concentration in saliva were significantly higher after 24 h of plaque accumulation. Rinsing with the mineral-enriching solution produced retention of fluoride and phosphate in the outer and middle layers of plaque. Salivary calcium concentration had a direct effect on fluoride uptake in plaque, but no obvious relationship was found between other salivary variables and the plaque fluoride retention. The salivary calcium effect may be due to enhanced bacterial cell wall binding of fluoride via calcium bridging. Copyright 2002 S. Karger AG, Basel

Condensed matter studies by nuclear methods

International Nuclear Information System (INIS)

Krolas, K.; Tomala, K.

1988-01-01

The separate abstract was prepared for 1 of the papers in this volume. The remaining 13 papers dealing with the use but not with advances in the use of nuclear methods in studies of condensed matter, were considered outside the subject scope of INIS. (M.F.W.)

Runtime and Inversion Impacts on Estimation of Moisture Retention Relations by Centrifuge

Science.gov (United States)

Sigda, J. M.; Wilson, J. L.

2003-12-01

Standard laboratory methods in soil physics for measuring the moisture retention relation (drainage matric potential-volumetric moisture content relation) are each limited to only part of the moisture content range. Centrifuge systems allow intensive accurate measurements across much of the saturation range, and typically require much less time than traditional laboratory methods. An initially liquid-saturated sample is subjected to a stepwise-increasing series of angular velocities while carefully monitoring changes in liquid content. Angular velocity is held constant until the capillary and centrifugal forces equilibrate, forcing liquid flux to zero, and then a final average liquid content is noted. The procedure is repeated after increasing the angular velocity. Centrifuge measurement time is greatly reduced because the centrifugal body force gradient can far exceed the driving forces utilized in standard lab methods. Widely-used in the petroleum industry for decades, centrifuge measurement of moisture retention relations is seldom encountered in the soil physics or vadose hydrology literatures. Yet there is a need to better understand and improve the experimental methodology given the increasing number of centrifuges employed in these fields. Errors in centrifuge measurement of moisture retention relations originate from both experimental protocol and from data inversion. Like standard methods, centrifuge methods assume equilibrium conditions, and so are sensitive to errors introduced by insufficient runtimes. Unlike standard methods, centrifuge experiments require inversion of the angular velocity and average sample moisture content data to a location-specific pair of matric potential and moisture content values, The force balance causes matric potential and moisture content to vary with sample length while the sample is spinning. Numerous data inversion techniques exist, each yielding different moisture retention relations. We present analyses demonstrating

Wind Effects on Retention Time in Highway Ponds

DEFF Research Database (Denmark)

Bentzen, Thomas Ruby; Larsen, Torben; Rasmussen, Michael R.

2007-01-01

is to evaluate the quality of long term simulations based on historical rain series of the pollutant discharges from roads and highways. The idea of this paper is to evaluate the effects of wind on the retention time and compare the retention time for the situation of a spatial uniform wind shear stress...... with the situation of a "real" spatial non-uniform shear stress distribution on the surface of the pond. The result of this paper shows that wind plays a dominant role for the retention time and flow pattern. Furthermore, the results shows that the differences in retention time between the use of uniform and non...

Wind Effects on Retention Time in Highway Ponds

DEFF Research Database (Denmark)

Bentzen, Thomas Ruby; Larsen, Torben; Rasmussen, Michael R.

2008-01-01

is to evaluate the quality of long term simulations based on historical rain series of the pollutant discharges from roads and highways. The idea of this paper is to evaluate the effects of wind on the retention time and compare the retention time for the situation of a spatial uniform wind shear stress...... with the situation of a "real" spatial non-uniform shear stress distribution on the surface of the pond. The result of this paper shows that wind plays a dominant role for the retention time and flow pattern. Furthermore, the results shows that the differences in retention time between the use of uniform and non...

Nicotine delivery, retention and pharmacokinetics from various electronic cigarettes.

Science.gov (United States)

St Helen, Gideon; Havel, Christopher; Dempsey, Delia A; Jacob, Peyton; Benowitz, Neal L

2016-03-01

To measure the systemic retention of nicotine, propylene glycol (PG) and vegetable glycerin (VG) in electronic cigarette (e-cigarette) users, and assess the abuse liability of e-cigarettes by characterizing nicotine pharmacokinetics. E-cigarette users recruited over the internet participated in a 1-day research ward study. Subjects took 15 puffs from their usual brand of e-cigarette. Exhaled breath was trapped in gas-washing bottles and blood was sampled before and several times after use. San Francisco, California, USA. Thirteen healthy, experienced adult e-cigarette users (six females and seven males). Plasma nicotine was analyzed by gas chromatography-mass spectrometry (GC-MS/MS) and nicotine, VG and PG in e-liquids and gas traps were analyzed by LC-MS/MS. Heart rate changes and subjective effects were assessed. E-cigarettes delivered an average of 1.33 (0.87-1.79) mg [mean and 95% confidence interval (CI)] of nicotine, and 93.8% of the inhaled dose, 1.22 (0.80-1.66) was systemically retained. Average maximum plasma nicotine concentration (Cmax ) was 8.4 (5.4-11.5) ng/ml and time of maximal concentration (Tmax ) was 2-5 minutes. One participant had Tmax of 30 minutes. 84.4% and 91.7% of VG and PG, respectively, was systemically retained. Heart rate increased by an average of 8.0 beats per minute after 5 minutes. Withdrawal and urge to smoke decreased and the e-cigarettes were described as satisfying. E-cigarettes can deliver levels of nicotine that are comparable to or higher than typical tobacco cigarettes, with similar systemic retention. Although the average maximum plasma nicotine concentration in experienced e-cigarette users appears to be generally lower than what has been reported from tobacco cigarette use, the shape of the pharmacokinetic curve is similar, suggesting addictive potential. © 2015 Society for the Study of Addiction.

Retention and failure morphology of prefabricated posts

DEFF Research Database (Denmark)

Sahafi, Alireza; Peutzfeldt, Anne; Asmussen, Erik

2004-01-01

PURPOSE: This study evaluated the effect of cement, post material, surface treatment, and shape (1) on the retention of posts luted in the root canals of extracted human teeth and (2) on the failure morphology. MATERIALS AND METHODS: Posts of titanium alloy (ParaPost XH), glass fiber (Para...... at 37 degrees C for 7 days, retention was determined by extraction of the posts. Failure morphology of extracted posts was analyzed and quantified stereomicroscopically. RESULTS: Type of luting cement, post material, and shape of post influenced the retention and failure morphology of the posts. Because...

Urinary retention associated with herpes zoster infection.

Science.gov (United States)

Cohen, L M; Fowler, J F; Owen, L G; Callen, J P

1993-01-01

Herpes zoster infection particularly involving the sacral dermatomes has been associated with bladder and bowel dysfunction, most commonly urinary retention. We report two patients who developed acute urinary retention, one of whom also had constipation, within days of herpes zoster skin lesions of the S2-S4 dermatomes. Herpes zoster is a reversible cause of neurogenic bladder and bowel dysfunction and should be considered in a patient that presents with acute urinary retention and/or constipation. Sensory abnormalities and flaccid detrusor paralysis are most likely involved in the pathogenesis.

Quantifying Cerebellum Grey Matter and White Matter Perfusion Using Pulsed Arterial Spin Labeling

Science.gov (United States)

Li, Xiufeng; Sarkar, Subhendra N.; Purdy, David E.; Briggs, Richard W.

2014-01-01

To facilitate quantification of cerebellum cerebral blood flow (CBF), studies were performed to systematically optimize arterial spin labeling (ASL) parameters for measuring cerebellum perfusion, segment cerebellum to obtain separate CBF values for grey matter (GM) and white matter (WM), and compare FAIR ASST to PICORE. Cerebellum GM and WM CBF were measured with optimized ASL parameters using FAIR ASST and PICORE in five subjects. Influence of volume averaging in voxels on cerebellar grey and white matter boundaries was minimized by high-probability threshold masks. Cerebellar CBF values determined by FAIR ASST were 43.8 ± 5.1 mL/100 g/min for GM and 27.6 ± 4.5 mL/100 g/min for WM. Quantitative perfusion studies indicated that CBF in cerebellum GM is 1.6 times greater than that in cerebellum WM. Compared to PICORE, FAIR ASST produced similar CBF estimations but less subtraction error and lower temporal, spatial, and intersubject variability. These are important advantages for detecting group and/or condition differences in CBF values. PMID:24949416

Quantifying Cerebellum Grey Matter and White Matter Perfusion Using Pulsed Arterial Spin Labeling

Directory of Open Access Journals (Sweden)

Xiufeng Li

2014-01-01

Full Text Available To facilitate quantification of cerebellum cerebral blood flow (CBF, studies were performed to systematically optimize arterial spin labeling (ASL parameters for measuring cerebellum perfusion, segment cerebellum to obtain separate CBF values for grey matter (GM and white matter (WM, and compare FAIR ASST to PICORE. Cerebellum GM and WM CBF were measured with optimized ASL parameters using FAIR ASST and PICORE in five subjects. Influence of volume averaging in voxels on cerebellar grey and white matter boundaries was minimized by high-probability threshold masks. Cerebellar CBF values determined by FAIR ASST were 43.8 ± 5.1 mL/100 g/min for GM and 27.6 ± 4.5 mL/100 g/min for WM. Quantitative perfusion studies indicated that CBF in cerebellum GM is 1.6 times greater than that in cerebellum WM. Compared to PICORE, FAIR ASST produced similar CBF estimations but less subtraction error and lower temporal, spatial, and intersubject variability. These are important advantages for detecting group and/or condition differences in CBF values.

Quantifying cerebellum grey matter and white matter perfusion using pulsed arterial spin labeling.

Science.gov (United States)

Li, Xiufeng; Sarkar, Subhendra N; Purdy, David E; Briggs, Richard W

2014-01-01

To facilitate quantification of cerebellum cerebral blood flow (CBF), studies were performed to systematically optimize arterial spin labeling (ASL) parameters for measuring cerebellum perfusion, segment cerebellum to obtain separate CBF values for grey matter (GM) and white matter (WM), and compare FAIR ASST to PICORE. Cerebellum GM and WM CBF were measured with optimized ASL parameters using FAIR ASST and PICORE in five subjects. Influence of volume averaging in voxels on cerebellar grey and white matter boundaries was minimized by high-probability threshold masks. Cerebellar CBF values determined by FAIR ASST were 43.8 ± 5.1 mL/100 g/min for GM and 27.6 ± 4.5 mL/100 g/min for WM. Quantitative perfusion studies indicated that CBF in cerebellum GM is 1.6 times greater than that in cerebellum WM. Compared to PICORE, FAIR ASST produced similar CBF estimations but less subtraction error and lower temporal, spatial, and intersubject variability. These are important advantages for detecting group and/or condition differences in CBF values.

Drug Retention Times

Energy Technology Data Exchange (ETDEWEB)

Center for Human Reliability Studies

2007-05-01

The purpose of this monograph is to provide information on drug retention times in the human body. The information provided is based on plausible illegal drug use activities that might be engaged in by a recreational drug user.

Use of Code-Switching in Multilingual Content Subject and Language Classrooms

Science.gov (United States)

Gwee, Susan; Saravanan, Vanithamani

2018-01-01

Research literature has shown that teachers code-switched to a language which is not the medium of instruction to help students understand subject matter and establish interpersonal relations with them. However, little is known about the extent to which teachers code-switch in content subject classrooms compared to language classrooms. Using…

Promoting Special Educator Teacher Retention

Directory of Open Access Journals (Sweden)

Jeremy E. Vittek

2015-06-01

Full Text Available This article is a critical review of the literature on special education teacher attrition and retention. The research focused on journal articles from 2004 to present. The results of the study helped define special educator attrition and retention. The major themes present in the findings were job satisfaction, administrative support, induction programs, and mentoring. The literature shows a clear need for comprehensive administrative support to improve job satisfaction and the likelihood a special educator will remain in their job.

Introduction. Cosmology meets condensed matter.

Science.gov (United States)

Kibble, T W B; Pickett, G R

2008-08-28

At first sight, low-temperature condensed-matter physics and early Universe cosmology seem worlds apart. Yet, in the last few years a remarkable synergy has developed between the two. It has emerged that, in terms of their mathematical description, there are surprisingly close parallels between them. This interplay has been the subject of a very successful European Science Foundation (ESF) programme entitled COSLAB ('Cosmology in the Laboratory') that ran from 2001 to 2006, itself built on an earlier ESF network called TOPDEF ('Topological Defects: Non-equilibrium Field Theory in Particle Physics, Condensed Matter and Cosmology'). The articles presented in this issue of Philosophical Transactions A are based on talks given at the Royal Society Discussion Meeting 'Cosmology meets condensed matter', held on 28 and 29 January 2008. Many of the speakers had participated earlier in the COSLAB programme, but the strength of the field is illustrated by the presence also of quite a few new participants.

The Problem of Subject Access to Visual Materials

Directory of Open Access Journals (Sweden)

Heather P. Jespersen

2004-09-01

Full Text Available This article discusses the problem of giving subject access to works of art. We survey both concept-based and content-based access by computers and by indexers/catalogers respectively, as well as issues of interoperability, database and indexer consistency, and cataloging standards. The authors, both of whom are trained art historians, question attempts to mystify fine art subject matter by the creation of clever library science systems that are executed by the naive. Only when trained art historians and knowledgeable catalogers are finally responsible for providing subject access to works of art, will true interoperability and consistency happen.

Vocation, friendship and resilience: a study exploring nursing student and staff views on retention and attrition.

Science.gov (United States)

Williamson, Graham R; Health, Val; Proctor-Childs, Tracey

2013-01-01

There is international concern about retention of student nurses on undergraduate programmes. United Kingdom Higher Education Institutions are monitored on their attrition statistics and can be penalised financially, so they have an incentive to help students remain on their programmes beyond their moral duty to ensure students receive the best possible educational experience. to understand students' and staff concerns about programmes and placements as part of developing our retention strategies. This study reports qualitative data on retention and attrition collected as part of an action research study. One University School of Nursing and Midwifery in the South West of England. Staff, current third year and ex-student nurses from the adult field. Data were collected in focus groups, both face-to face and virtual, and individual telephone interviews. These were transcribed and subjected to qualitative content analysis. FOUR THEMES EMERGED: Academic support, Placements and mentors, Stresses and the reality of nursing life, and Dreams for a better programme. The themes Academic support, Placements and mentors and Stresses and the reality of nursing life, resonate with international literature. Dreams for a better programme included smaller group learning. Vocation, friendship and resilience seem instrumental in retaining students, and Higher Education Institutions should work to facilitate these. 'Vocation' has been overlooked in the retention discussions, and working more actively to foster vocation and belongingness could be important.

Retention performance of green roofs in three different climate regions

Science.gov (United States)

Sims, Andrew W.; Robinson, Clare E.; Smart, Charles C.; Voogt, James A.; Hay, Geoffrey J.; Lundholm, Jeremey T.; Powers, Brandon; O'Carroll, Denis M.

2016-11-01

Green roofs are becoming increasingly popular for moderating stormwater runoff in urban areas. This study investigated the impact different climates have on the retention performance of identical green roofs installed in London Ontario (humid continental), Calgary Alberta (semi-arid, continental), and Halifax Nova Scotia (humid, maritime). Drier climates were found to have greater percent cumulative stormwater retention with Calgary (67%) having significantly better percent retention than both London (48%) and Halifax (34%). However, over the same study period the green roof in London retained the greatest depth of stormwater (598 mm), followed by the green roof in Halifax (471 mm) and then Calgary (411 mm). The impact of climate was largest for medium sized storms where the antecedent moisture condition (AMC) at the beginning of a rainfall event governs retention performance. Importantly AMC was a very good predictor of stormwater retention, with similar retention at all three sites for a given AMC, emphasizing that AMC is a relevant indicator of retention performance in any climate. For large rainfall events (i.e., >45 mm) green roof average retention ranged between 16% and 29% in all cities. Overall, drier climates have superior retention due to lower AMC in the media. However, moderate and wet climates still provide substantial total volume reduction benefits.

Herpes zoster-induced acute urinary retention.

Science.gov (United States)

Addison, Ben; Harvey, Martyn

2013-06-01

Urinary retention is a common acute presentation for men in their later decades. Potential contributing pathologies are numerous. We report an unusual case of acute urinary retention requiring catheterisation secondary to sacral herpes zoster reactivation (S2-4) in an 88-year-old man with minimal preceding obstructive symptoms. © 2013 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.

Regional White Matter Decreases in Alzheimer's Disease Using Optimized Voxel-Based Morphometry

Energy Technology Data Exchange (ETDEWEB)

Shuyu Li; Fang Pu; Feng Shi; Sheng Xie; Yinhua Wang; Tianzi Jiang [Dept. of Bioengineering, Beijing Univ. of Aeronautics and Astronautics, Beijing (China)

2008-02-15

Background: Most studies that attempt to clarify structural abnormalities related to functional disconnection in patients with Alzheimer's disease (AD) have focused on exploring pathological changes in cortical gray matter. However, white matter fibers connecting these cerebral areas may also be abnormal. Purpose: To investigate the regional changes of white matter volume in patients with AD compared to healthy subjects. Material and Methods: White matter volume changes in whole-brain magnetic resonance images acquired from 19 patients with AD and 20 healthy subjects (control group) were observed using the optimized voxel-based morphometry (VBM) method. In addition, the corpus callosum (CC) of AD patients and the control group was investigated further by outlining manually the boundary of the CC on a midsagittal slice. Each area of the CC was then corrected by dividing each subject's intracranial area in the midsagittal plane. Results: Compared with the control group, AD patients showed significantly reduced white matter volumes in the posterior part of the CC and the temporal lobe in the left and right hemispheres. Moreover, the voxel showing peak statistical difference in the posterior of the CC was left sided. The five subdivisions of the CC were also significantly smaller among the AD patients relative to the control group. Conclusion: Our findings suggest that these abnormalities in white matter regions may contribute to the functional disconnections in AD.

Regional White Matter Decreases in Alzheimer's Disease Using Optimized Voxel-Based Morphometry

Energy Technology Data Exchange (ETDEWEB)

Shuyu Li; Fang Pu; Feng Shi; Sheng Xie; Yinhua Wang; Tianzi Jiang (Dept. of Bioengineering, Beijing Univ. of Aeronautics and Astronautics, Beijing (China))

2008-02-15

Background: Most studies that attempt to clarify structural abnormalities related to functional disconnection in patients with Alzheimer's disease (AD) have focused on exploring pathological changes in cortical gray matter. However, white matter fibers connecting these cerebral areas may also be abnormal. Purpose: To investigate the regional changes of white matter volume in patients with AD compared to healthy subjects. Material and Methods: White matter volume changes in whole-brain magnetic resonance images acquired from 19 patients with AD and 20 healthy subjects (control group) were observed using the optimized voxel-based morphometry (VBM) method. In addition, the corpus callosum (CC) of AD patients and the control group was investigated further by outlining manually the boundary of the CC on a midsagittal slice. Each area of the CC was then corrected by dividing each subject's intracranial area in the midsagittal plane. Results: Compared with the control group, AD patients showed significantly reduced white matter volumes in the posterior part of the CC and the temporal lobe in the left and right hemispheres. Moreover, the voxel showing peak statistical difference in the posterior of the CC was left sided. The five subdivisions of the CC were also significantly smaller among the AD patients relative to the control group. Conclusion: Our findings suggest that these abnormalities in white matter regions may contribute to the functional disconnections in AD

Integration of Digital Technology and Innovative Strategies for Learning and Teaching Large Classes: A Calculus Case Study

Science.gov (United States)

Vajravelu, Kuppalapalle; Muhs, Tammy

2016-01-01

Successful science and engineering programs require proficiency and dynamics in mathematics classes to enhance the learning of complex subject matter with a sufficient amount of practical problem solving. Improving student performance and retention in mathematics classes requires inventive approaches. At the University of Central Florida (UCF) the…

A Discussion of SY-101 Crust Gas Retention and Release Mechanisms

International Nuclear Information System (INIS)

Mendoza, D.P.; Mahoney, L.A.; Gauglitz, P.A.; Rassat, S.D.; Caley, S.M.

1999-01-01

The flammable gas hazard in Hanford waste tanks was made an issue by the behavior of double-shell Tank (DST) 241-SY-101 (SY-101). Shortly after SY-101 was filled in 1980, the waste level began rising periodically, due to the generation and retention of gases within the slurry, and then suddenly dropping as the gases were released. An intensive study of the tank's behavior revealed that these episodic releases posed a safety hazard because the released gas was flammable, and, in some cases, the volume of gas released was sufficient to exceed the lower flammability limit (LFL) in the tank headspace (Alleinann et al. 1993). A mixer pump was installed in SY-101 in late 1993 to prevent gases from building up in the settled solids layer, and the large episodic gas releases have since ceased (Allemann et al. 1994; Stewart et al. 1994; Brewster et al. 1995). However, the surface level of SY-101 has been increasing since at least 1995, and in recent months the level growth has shown significant and unexpected acceleration. Based on a number of observations and measurements, including data from the void fraction instrument (VFI), we have concluded that the level growth is caused largely by increased gas retention in the floating crust. In September 1998, the crust contained between about 21 and 43% void based on VFI measurements (Stewart et al. 1998). Accordingly, it is important to understand the dominant mechanisms of gas retention, why the gas retention is increasing, and whether the accelerating level increase will continue, diminish or even reverse. It is expected that the retained gas in the crust is flammable, with hydrogen as a major constituent. This gas inventory would pose a flammable gas hazard if it were to release suddenly. In May 1997, the mechanisms of bubble retention and release from crust material were the subject of a workshop. The evaluation of the crust and potential hazards assumed a more typical void of roughly 15% gas. It could be similar to

A Discussion of SY-101 Crust Gas Retention and Release Mechanisms

Energy Technology Data Exchange (ETDEWEB)

SD Rassat; PA Gauglitz; SM Caley; LA Mahoney; DP Mendoza

1999-02-23

The flammable gas hazard in Hanford waste tanks was made an issue by the behavior of double-shell Tank (DST) 241-SY-101 (SY-101). Shortly after SY-101 was filled in 1980, the waste level began rising periodically, due to the generation and retention of gases within the slurry, and then suddenly dropping as the gases were released. An intensive study of the tank's behavior revealed that these episodic releases posed a safety hazard because the released gas was flammable, and, in some cases, the volume of gas released was sufficient to exceed the lower flammability limit (LFL) in the tank headspace (Allemann et al. 1993). A mixer pump was installed in SY-101 in late 1993 to prevent gases from building up in the settled solids layer, and the large episodic gas releases have since ceased (Allemann et al. 1994; Stewart et al. 1994; Brewster et al. 1995). However, the surface level of SY-101 has been increasing since at least 1995, and in recent months the level growth has shown significant and unexpected acceleration. Based on a number of observations and measurements, including data from the void fraction instrument (VFI), we have concluded that the level growth is caused largely by increased gas retention in the floating crust. In September 1998, the crust contained between about 21 and 43% void based on VFI measurements (Stewart et al. 1998). Accordingly, it is important to understand the dominant mechanisms of gas retention, why the gas retention is increasing, and whether the accelerating level increase will continue, diminish or even reverse. It is expected that the retained gas in the crust is flammable, with hydrogen as a major constituent. This gas inventory would pose a flammable gas hazard if it were to release suddenly. In May 1997, the mechanisms of bubble retention and release from crust material were the subject of a workshop. The evaluation of the crust and potential hazards assumed a more typical void of roughly 15% gas. It could be similar to

A White Paper on keV sterile neutrino Dark Matter

Czech Academy of Sciences Publication Activity Database

Adhikari, R.; Agostini, M.; Ky, N. A.; Araki, T.; Archidiacono, M.; Bahr, M.; Baur, J.; Dragoun, Otokar; Vénos, Drahoslav; Zuber, K.

2017-01-01

Roč. 2017, č. 1 (2017), č. článku 025. ISSN 1475-7516 R&D Projects: GA ČR(CZ) GAP203/12/1896 Institutional support: RVO:61389005 Keywords : cosmological neutrinos * dark matter experiments * dark matter theory * particle physics - cosmology connection Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics OBOR OECD: Astronomy (including astrophysics,space science) Impact factor: 4.734, year: 2016

Lessons in participant retention in the course of a randomized controlled clinical trial.

Science.gov (United States)

Idoko, Olubukola T; Owolabi, Olumuyiwa A; Odutola, Aderonke A; Ogundare, Olatunde; Worwui, Archibald; Saidu, Yauba; Smith-Sanneh, Alison; Tunkara, Abdoulie; Sey, Gibbi; Sanyang, Assan; Mendy, Philip; Ota, Martin O C

2014-10-09

Clinical trials are increasingly being conducted as new products seek to enter the market. Deployment of such interventions is based on evidence obtained mainly from the gold standard of randomized controlled clinical trials (RCCT). A crucial factor in the ability of RCCTs to provide credible and generalisable data is sample size and retention of the required number of subjects at completion of the follow-up period. However, recruitment and retention in clinical trials are hindered by prevalent peculiar challenges in Africa that need to be circumvented. This article shares experiences from a phase II trial that recorded a high retention rate at 14 months follow-up at a new clinical trial site. Mothers bringing children less than two months of age to the health facility were given information and invited to have their child enrolled if the inclusion criteria were fulfilled. Participants were enrolled over 8 months. Trial procedures, duration and risks/benefits were painstakingly and sequentially explained to the communities, parents and relevant relatives before and during the trial period. The proportions of participants that completed or did not complete the trial were analyzed including the reasons for failure to complete all trial procedures. 1044 individuals received information regarding the trial of which 371 returned for screening. 300 (81%) of them who fulfilled the inclusion criteria and did not meet any exclusion criteria were enrolled and 94% of these completed the trial. Consent withdrawal was the main reason for not completing the trial largely (75%) due to the father not being involved at the point of consenting or parents no longer being comfortable with blood sampling. Participant retention in clinical trials remains a crucial factor in ensuring generalisability of trial data. Appropriate measures to enhance retention should include continuous community involvement in the process, adequate explanation of trial procedures and risks/benefits; and

α particles and the ''pasta'' phase in nuclear matter

International Nuclear Information System (INIS)

Avancini, S. S.; Barros, C. C. Jr.; Menezes, D. P.; Providencia, C.

2010-01-01

The effects of the α particles in nuclear matter at low densities are investigated within three different parametrizations of relativistic models at finite temperature. Both homogeneous and inhomogeneous matter (pasta phase) are described for neutral nuclear matter with fixed proton fractions and stellar matter subject to β equilibrium and trapped neutrinos. In homogeneous matter, α particles are present only at densities below 0.02 fm -3 and their presence decreases with increase of the temperature and, for a fixed temperature, the α particle fraction decreases for smaller proton fractions. A repulsive interaction is important to mimic the dissolution of the clusters in homogeneous matter. The effect of the α particles on the pasta structure is very small except close to the critical temperatures and/or proton fractions, when it may still predict a pasta phase while no pasta phase would occur in the absence of light clusters. It is shown that for densities above 0.01 fm 3 the α-particle fraction in the pasta phase is much larger than that in homogeneous matter.

Hypertension and white matter lesions are independently associated with apathetic behavior in healthy elderly subjects. The Sefuri brain MRI study

International Nuclear Information System (INIS)

Yao, Hiroshi; Takashima, Yuki; Mori, Takahiro; Hashimoto, Manabu; Yuzuriha, Takefumi; Uchino, Akira; Miwa, Yoshikazu; Sasaguri, Toshiyuki

2009-01-01

Apathy is defined as a syndrome of primary loss of motivation not attributable to emotional distress, intellectual impairment or consciousness disturbance. The aim of our study was to investigate the effects of vascular risk factors and silent ischemic brain lesions on apathetic behavior of community-dwelling elderly subjects. Brain MRI and other medical examinations were performed on 222 non-demented community-dwelling elderly subjects (96 men and 126 women, average age 70.1 years). The apathy group was defined as the most apathetic quintile determined by Starkstein's apathy scale. Silent infarction, deep white matter lesions (DWMLs) and periventricular hyperintensities were detected in 12.2, 39.2 and 22.5%, respectively. Linear regression analysis (Pearson) revealed that the scores on the apathy scale correlated slightly but significantly with logarithmically transformed scores of the Modified Stroop Test (r=0.135, P=0.045), but not with the Mini-Mental State Examination. The apathy group tended to have more high blood pressure (141.6/82.6 vs. 136.1/79.6 mmHg), less prevalent hyperlipidemia (18 vs. 35%) and lower serum albumin. Multivariate analysis (the forward stepwise method of logistic analysis) revealed an independent correlation between the apathy and grade of DWMLs (odds ratio 1.826, 95% confidence interval (CI) 1.129-2.953 per grade) or diastolic blood pressure (DBP) (odds ratio 1.055, 95% CI 1.0 14-1.098 per mmHg) after adjusting for possible confounders. The mean apathy scale score in the DBP≥90 mmHg group was significantly lower (more apathetic) than that in the DBP<80 group (P=0.011, analysis of covariance). This study showed that hypertension and DWMLs are independently associated with apathy in healthy elderly subjects. (author)

P Status In Andisol And P Content In Arabica Coffee Seedling Leaves Due To The Application Of Phosphate Providing Microorganisms And Organic Matters In Bener Meriah District

Directory of Open Access Journals (Sweden)

Hifnalisa

2017-09-01

Full Text Available Bener Meriah district is one of the arabica coffee producing regions in Indonesia. Most of arabica coffee in Bener Meriah district grown on Andisol. Generally the availability of P in Andisol is very low. Phosphate providing microorganisms and organic matters can be used to increase Andisol P availability. The objective of this study was to examine the effect of the application of phosphate providing microorganisms and organic matters on P status in Andisol and P content in arabica coffee seedlings leaves in Bener Meriah district. The experiment used a randomized block design that consisted of two factors. Factor I was the application of phosphate providing microorganisms consisting of without microorganisms Glomus sp. Kurthia sp. Corynebacterium sp. and Listeria sp. Factor II was the application of organic matters consisting of T. diversifolia and coffee bean skins. The results of the study showed that Glomus sp. Kurthia sp. Corynebacterium sp. and Listeria sp. decreased soil P-retention by 2.38 5.12 7.48 9.17 respectively increased soil P-available by 24.85 36.03 52.79 77.33 respectively and increased P-content in the arabica coffee seedling leaves by 22.22 33.33 37.0372.27 respectively compared to without the application of microorganisms. The application of coffee bean skins resulted in lower soil P-retention higher soil P-available and P-content in arabica coffee seedling leaves than T. diversifolia. The application of Listeria sp.-coffee bean skins resulted in the lowest soil P-retention the highest soil P-available and P-content in arabica coffee seedlings leaves.

Retention and chemical speciation of uranium in an oxidized wetland sediment from the Savannah River Site

Energy Technology Data Exchange (ETDEWEB)

Li, Dien; Seaman, John C.; Chang, Hyun-Shik; Jaffe, Peter R.; Koster van Groos, Paul; Jiang, De-Tong; Chen, Ning; Lin, Jinru; Arthur, Zachary; Pan, Yuanming; Scheckel, Kirk G.; Newville, Matthew; Lanzirotti, Antonio; Kaplan, Daniel I.

2014-05-01

Uranium speciation and retention mechanism onto Savannah River Site (SRS) wetland sediments was studied using batch (ad)sorption experiments, sequential extraction desorption tests and U L{sub 3}-edge X-ray absorption near-edge structure (XANES) spectroscopy of contaminated wetland sediments. U was highly retained by the SRS wetland sediments. In contrast to other similar but much lower natural organic matter (NOM) sediments, significant sorption of U onto the SRS sediments was observed at pH <4 and pH >8. Sequential extraction tests indicated that the U(VI) species were primarily associated with the acid soluble fraction (weak acetic acid extractable) and NOM fraction (Na-pyrophosphate extractable). Uranium L3- edge XANES spectra of the U-retained sediments were nearly identical to that of uranyl acetate. The primary oxidation state of U in these sediments was as U(VI), and there was little evidence that the high sorptive capacity of the sediments could be ascribed to abiotic or biotic reduction to the less soluble U(IV) species. The molecular mechanism responsible for the high U retention in the SRS wetland sediments is likely related to the chemical bonding of U to organic carbon.

Effect of exercise on deposition and subsequent retention of inhaled particles

International Nuclear Information System (INIS)

Bennett, W.D.; Messina, M.S.; Smaldone, G.C.

1985-01-01

To investigate the effect of exercise and its associated increase in ventilation on the deposition and subsequent retention of inhaled particles, we measured the fractional and regional lung deposition of a radioactively tagged (/sup 99m/Tc) monodisperse aerosol (2.6 microns mass median aerodynamic diam) in normal human subjects at rest and while exercising on a bicycle ergometer. Breath-by-breath deposition fraction (DF) was measured throughout the aerosol exposures by Tyndallometry. Following each exposure gamma camera analysis was used to 1) determine the regional distribution of deposited particles and 2) monitor lung retention for 2.5 h and again at 24 h. We found that DF was unchanged between ventilation at rest (6-10 l/min) and exercise (32-46 l/min). Even though mouth deposition was enhanced with exercise, it was not large enough to produce a significant difference in the deposition fraction of the lung (DFL) between resting and exercise exposures. The central-to-peripheral distribution of deposited aerosol was larger for the exercise vs. resting exposure, reflecting a shift of particle deposition to more central bronchial airways. Apical-to-basal distribution was not different for the two exposures. Retention at 2.5 h and 24 h (R24) was reduced following the exercise vs. the resting exposure, consistent with greater bronchial deposition during exercise. The product of DFL and R24 gave a measure of fractional burden at 24 h (B24), i.e., the fraction of inhaled aerosol residing in the lungs 24 h after exposure. B24 was not significantly different between rest and exercise exposures

Nuclear reactor melt-retention structure to mitigate direct containment heating

Science.gov (United States)

Tutu, Narinder K.; Ginsberg, Theodore; Klages, John R.

1991-01-01

A light water nuclear reactor melt-retention structure to mitigate the extent of direct containment heating of the reactor containment building. The structure includes a retention chamber for retaining molten core material away from the upper regions of the reactor containment building when a severe accident causes the bottom of the pressure vessel of the reactor to fail and discharge such molten material under high pressure through the reactor cavity into the retention chamber. In combination with the melt-retention chamber there is provided a passageway that includes molten core droplet deflector vanes and has gas vent means in its upper surface, which means are operable to deflect molten core droplets into the retention chamber while allowing high pressure steam and gases to be vented into the upper regions of the containment building. A plurality of platforms are mounted within the passageway and the melt-retention structure to direct the flow of molten core material and help retain it within the melt-retention chamber. In addition, ribs are mounted at spaced positions on the floor of the melt-retention chamber, and grid means are positioned at the entrance side of the retention chamber. The grid means develop gas back pressure that helps separate the molten core droplets from discharged high pressure steam and gases, thereby forcing the steam and gases to vent into the upper regions of the reactor containment building.

effect of differentiated instructional strategies on students' retention

African Journals Online (AJOL)

PROF EKWUEME

show that retention ability was significantly higher in the experimental group ... Differentiated instruction, Lecture , Cognitive Achievement ,Retention ability, Geometry. ... thinking. Based on this knowledge, differentiated instruction applies an ...

The more total cognitive load is reduced by cues, the better retention and transfer of multimedia learning: A meta-analysis and two meta-regression analyses.

Science.gov (United States)

Xie, Heping; Wang, Fuxing; Hao, Yanbin; Chen, Jiaxue; An, Jing; Wang, Yuxin; Liu, Huashan

2017-01-01

Cueing facilitates retention and transfer of multimedia learning. From the perspective of cognitive load theory (CLT), cueing has a positive effect on learning outcomes because of the reduction in total cognitive load and avoidance of cognitive overload. However, this has not been systematically evaluated. Moreover, what remains ambiguous is the direct relationship between the cue-related cognitive load and learning outcomes. A meta-analysis and two subsequent meta-regression analyses were conducted to explore these issues. Subjective total cognitive load (SCL) and scores on a retention test and transfer test were selected as dependent variables. Through a systematic literature search, 32 eligible articles encompassing 3,597 participants were included in the SCL-related meta-analysis. Among them, 25 articles containing 2,910 participants were included in the retention-related meta-analysis and the following retention-related meta-regression, while there were 29 articles containing 3,204 participants included in the transfer-related meta-analysis and the transfer-related meta-regression. The meta-analysis revealed a statistically significant cueing effect on subjective ratings of cognitive load (d = -0.11, 95% CI = [-0.19, -0.02], p < 0.05), retention performance (d = 0.27, 95% CI = [0.08, 0.46], p < 0.01), and transfer performance (d = 0.34, 95% CI = [0.12, 0.56], p < 0.01). The subsequent meta-regression analyses showed that dSCL for cueing significantly predicted dretention for cueing (β = -0.70, 95% CI = [-1.02, -0.38], p < 0.001), as well as dtransfer for cueing (β = -0.60, 95% CI = [-0.92, -0.28], p < 0.001). Thus in line with CLT, adding cues in multimedia materials can indeed reduce SCL and promote learning outcomes, and the more SCL is reduced by cues, the better retention and transfer of multimedia learning.

The Causal Effects of Grade Retention on Behavioral Outcomes

Science.gov (United States)

Martorell, Paco; Mariano, Louis T.

2018-01-01

This study examines the impact of grade retention on behavioral outcomes under a comprehensive assessment-based student promotion policy in New York City. To isolate the causal effect of grade retention, we implement a fuzzy regression discontinuity (RD) design that exploits the fact that grade retention is largely determined by whether a student…

Relationship between potassium intake and radiocesium retention in the reindeer

International Nuclear Information System (INIS)

Holleman, D.F.; Luick, J.R.

1975-01-01

The effect of dietary potassium on radiocesium retention was studied in reindeer fed winter diets of lichens. Potassium added to the diet markedly decreased radiocesium retention; this suggests that seasonal changes in cesium retention observed earlier in reindeer might be caused largely by nutritional factors. Data indicate that a 20-fold increase in dietary potassium results in a 2-fold decrease in radiocesium retention

Record Retention Practices among the Nation's “Most Wired” Hospitals

OpenAIRE

Rinehart-Thompson, Laurie A.

2008-01-01

This exploratory study examined health record retention practices among health information management professionals in acute care general hospitals in the United States. A descriptive research design was used, and data were collected using a self-reporting survey. Respondents answered questions about record retention policies, the responsibility of health information professionals in policy administration, record retention periods, factors that determine retention periods, and other informati...

Studies on nitrogen retention in growing pigs

DEFF Research Database (Denmark)

Thorbek, G; Henckel, S; Chwalibog, André

1987-01-01

Nitrogen retention (RN) was measured in 60 barrows of Danish Landrace and a total of 470 balance periods was carried out during the growth period from 20 to 85 kg live weight. In the first serie (Expt A) six different feed compounds of high biological value (HBV) were fed to 48 barrows, while...... in the second serie (Expt B) 12 barrows were measured on feed compounds of HBV or low biological value (LBV). Three different levels of gross energy were used in Expt B. Individual differences of 10-20% in the pigs capability for nitrogen retention were observed. Nitrogen retention increased from 12 to 21 g N....../d on the HBV-compounds and was not influenced by increasing nitrogen or energy intake. Nitrogen retention was curvilinear in relation to metabolic live weight (kg0.75) in both series. A parabolic function on kg0.75 gave the best fit to the data with the following regression equations: Expt A + B: RN, g/d = 1...

The Association Between Health Program Participation and Employee Retention.

Science.gov (United States)

Mitchell, Rebecca J; Ozminkowski, Ronald J; Hartley, Stephen K

2016-09-01

Using health plan membership as a proxy for employee retention, the objective of this study was to examine whether use of health promotion programs was associated with employee retention. Propensity score weighted generalized linear regression models were used to estimate the association between telephonic programs or health risk surveys and retention. Analyses were conducted with six study samples based on type of program participation. Retention rates were highest for employees with either telephonic program activity or health risk surveys and lowest for employees who did not participate in any interventions. Participants ranged from 71% more likely to 5% less likely to remain with their employers compared with nonparticipants, depending on the sample used in analyses. Using health promotion programs in combination with health risk surveys may lead to improvements in employee retention.

Matter-antimatter and matter-matter interactions at intermediate energies

International Nuclear Information System (INIS)

Santos, Antonio Carlos Fontes dos

2002-01-01

This article presents some of the recent experimental advances on the study on antimatter-matter and matter-matter interactions, and some of the subtle differences stimulated a great theoretical efforts for explanation of the results experimentally observed

Gatherings as a retention strategy.

Science.gov (United States)

Stokes, Lillian Gatlin

2003-01-01

Retention has long been an issue for minority students enrolled in nursing programs. Indiana University put into place an initiative to enhance retention. The initiative is "Gatherings" which provide a means for maintaining contact and direct communication with minority/international students. Gatherings allow students at varied levels in the program to interact with each other and to share issues and concerns. Over a five-year period, the benefits of this initiative have been voiced by students. These students have strongly encouraged continuation of "gatherings". Plans are underway to start similar sessions for all students.

Mentoring--a staff retention tool.

Science.gov (United States)

Kanaskie, Mary Louise

2006-01-01

Staff retention presents a common challenge for hospitals nationwide. Mentorship programs have been explored as one method of creating environments that promote staff retention. Successful achievement of nurse competencies identified in the Synergy Model for Patient Care can best be achieved in an environment that encourages and facilitates mentoring. Mentoring relationships in critical care provide the ongoing interactions, coaching, teaching, and role modeling to facilitate nurses' progression along this continuum. Mentoring relationships offer support and professional development for nurses at all levels within an organization as well as an optimistic outlook for the nursing profession.

Mechanistic failure mode investigation and resolution of parvovirus retentive filters.

Science.gov (United States)

LaCasse, Daniel; Lute, Scott; Fiadeiro, Marcus; Basha, Jonida; Stork, Matthew; Brorson, Kurt; Godavarti, Ranga; Gallo, Chris

2016-07-08

Virus retentive filters are a key product safety measure for biopharmaceuticals. A simplistic perception is that they function solely based on a size-based particle removal mechanism of mechanical sieving and retention of particles based on their hydrodynamic size. Recent observations have revealed a more nuanced picture, indicating that changes in viral particle retention can result from process pressure and/or flow interruptions. In this study, a mechanistic investigation was performed to help identify a potential mechanism leading to the reported reduced particle retention in small virus filters. Permeate flow rate or permeate driving force were varied and analyzed for their impact on particle retention in three commercially available small virus retentive filters. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:959-970, 2016. © 2016 American Institute of Chemical Engineers.

Healthy imperfect dark matter from effective theory of mimetic cosmological perturbations

International Nuclear Information System (INIS)

Hirano, Shin'ichi; Nishi, Sakine; Kobayashi, Tsutomu

2017-01-01

We study the stability of a recently proposed model of scalar-field matter called mimetic dark matter or imperfect dark matter. It has been known that mimetic matter with higher derivative terms suffers from gradient instabilities in scalar perturbations. To seek for an instability-free extension of imperfect dark matter, we develop an effective theory of cosmological perturbations subject to the constraint on the scalar field's kinetic term. This is done by using the unifying framework of general scalar-tensor theories based on the ADM formalism. We demonstrate that it is indeed possible to construct a model of imperfect dark matter which is free from ghost and gradient instabilities. As a side remark, we also show that mimetic F (R) theory is plagued with the Ostrogradsky instability.

Healthy imperfect dark matter from effective theory of mimetic cosmological perturbations

Energy Technology Data Exchange (ETDEWEB)

Hirano, Shin' ichi; Nishi, Sakine; Kobayashi, Tsutomu, E-mail: s.hirano@rikkyo.ac.jp, E-mail: sakine@rikkyo.ac.jp, E-mail: tsutomu@rikkyo.ac.jp [Department of Physics, Rikkyo University, Toshima, Tokyo 171-8501 (Japan)

2017-07-01

We study the stability of a recently proposed model of scalar-field matter called mimetic dark matter or imperfect dark matter. It has been known that mimetic matter with higher derivative terms suffers from gradient instabilities in scalar perturbations. To seek for an instability-free extension of imperfect dark matter, we develop an effective theory of cosmological perturbations subject to the constraint on the scalar field's kinetic term. This is done by using the unifying framework of general scalar-tensor theories based on the ADM formalism. We demonstrate that it is indeed possible to construct a model of imperfect dark matter which is free from ghost and gradient instabilities. As a side remark, we also show that mimetic F (R) theory is plagued with the Ostrogradsky instability.

Neutral particle retention in the JET MK I divertor

International Nuclear Information System (INIS)

Ehrenberg, J.K.; Campbell, D.J.; Harbour, P.J.; Horton, L.D.; Loarte, A.; McCormick, G.K.; Monk, R.D.; Saibene, G.R.; Simonini, R.; Taroni, A.; Stamp, M.F.

1997-01-01

Retention of neutral deuterium and nitrogen in the JET MK I divertor has been investigated. Results show that ohmic plasma detachment reduces deuterium retention, that the magnetic divertor configuration has some influence on the achievable deuterium retention, and that nitrogen in nitrogen-seeded steady state detached H-mode discharges accumulates in the divertor. (orig.)

Substance use and regional gray matter volume in individuals at high risk of psychosis

OpenAIRE

Stone, James; Bhattacharyya, Sagnik; Barker, Gareth J; McGuire, Philip K; Bhattacharyya, Sagnik

2012-01-01

Individuals with an at risk mental state (ARMS) are at greatly increased risk of developing a psychotic illness. Risk of transition to psychosis is associated with regionally reduced cortical gray matter volume. There has been considerable interest in the interaction between psychosis risk and substance use. In this study we investigate the relationship between alcohol, cannabis and nicotine use with gray matter volume in ARMS subjects and healthy volunteers. Twenty seven ARMS subjects and 27...

“To be or not to be retained … That’s the question!”Retention,self - esteem,self - concept,achievement goalsand grades

Directory of Open Access Journals (Sweden)

Francisco Peixoto

2016-10-01

Full Text Available Keeping students back in the same grade – retention – has always been a controversial issue in Education, with some defending it as a beneficial remedial practice and others arguing against its detrimental effects. This paper undertakes an analysis of this issue, focusing on the differences in student motivation and self-related variables according to their retention related status, and the interrelationship between retention and these variables. The participants were 695 students selected from two cohorts (5th and 7th graders of a larger group of students followed over a three-year project. The students were assigned to four groups according to their retention-related status over time: 1 students with past and recent retention; 2 students with past but no recent retention; 3 students with no past but recent retention; 4 students with no past or recent retention. Measures of achievement goal orientations, self-concept, self-esteem, importance given to school subjects and Grade Point Average (GPA were collected for all students.Repeated measures MANCOVA analyses were carried out showing group differences in self-esteem, academic self-concept, importance attributed to academic competencies, task and avoidance orientation and academic achievement. To attain a deeper understanding of these results and to identify profiles across variables, a cluster analysis based on achievement goals was conducted and four clusters were identified. Students who were retained at the end of the school year are mainly represented in clusters with less adaptive motivational profiles and almost absent from clusters exhibiting more adaptive ones.Findings highlight that retention leaves a significant mark that remains even when students recover academic achievement and retention is in the distant past. This is reflected in the low academic self-concept as well as in the devaluation of academic competencies and in the avoidance orientation which, taken together, can

Evaluation of the production, composition and aluminum and iron complexation of algogenic organic matter

Czech Academy of Sciences Publication Activity Database

Pivokonský, Martin; Klouček, Ondřej; Pivokonská, Lenka

2006-01-01

Roč. 40, č. 16 (2006), s. 3045-3052 ISSN 0043-1354 R&D Projects: GA AV ČR KJB200600501 Institutional research plan: CEZ:AV0Z20600510 Keywords : affinity chromatography * algogenic organic matter * aluminum and iron coagulants * extracellular organic matter * molecular weight fractionation * intracellular organic matter Subject RIV: BK - Fluid Dynamics Impact factor: 2.459, year: 2006

Hysteresis of Soil Point Water Retention Functions Determined by Neutron Radiography

Science.gov (United States)

Perfect, E.; Kang, M.; Bilheux, H.; Willis, K. J.; Horita, J.; Warren, J.; Cheng, C.

2010-12-01

Soil point water retention functions are needed for modeling flow and transport in partially-saturated porous media. Such functions are usually determined by inverse modeling of average water retention data measured experimentally on columns of finite length. However, the resulting functions are subject to the appropriateness of the chosen model, as well as the initial and boundary condition assumptions employed. Soil point water retention functions are rarely measured directly and when they are the focus is invariably on the main drying branch. Previous direct measurement methods include time domain reflectometry and gamma beam attenuation. Here we report direct measurements of the main wetting and drying branches of the point water retention function using neutron radiography. The measurements were performed on a coarse sand (Flint #13) packed into 2.6 cm diameter x 4 cm long aluminum cylinders at the NIST BT-2 (50 μm resolution) and ORNL-HFIR CG1D (70 μm resolution) imaging beamlines. The sand columns were saturated with water and then drained and rewetted under quasi-equilibrium conditions using a hanging water column setup. 2048 x 2048 pixel images of the transmitted flux of neutrons through the column were acquired at each imposed suction (~10-15 suction values per experiment). Volumetric water contents were calculated on a pixel by pixel basis using Beer-Lambert’s law in conjunction with beam hardening and geometric corrections. The pixel rows were averaged and combined with information on the known distribution of suctions within the column to give 2048 point drying and wetting functions for each experiment. The point functions exhibited pronounced hysteresis and varied with column height, possibly due to differences in porosity caused by the packing procedure employed. Predicted point functions, extracted from the hanging water column volumetric data using the TrueCell inverse modeling procedure, showed very good agreement with the range of point

Going to the Heart of the Matter

Science.gov (United States)

Todd, Sharon

2011-01-01

Written as a conversational response to Rosa Luxemburg, this piece discusses the importance of going to the heart of the matter for education, seen here in terms of the actual flesh and blood subjects who are at the centre of a pedagogy of transformation.

Retention of anatomy knowledge by student radiographers

International Nuclear Information System (INIS)

Hall, A. Susanne; Durward, Brian R.

2009-01-01

Introduction: Anatomy has long been regarded as an integral part of the core curriculum. However, anecdotal evidence suggests that long-term retention of anatomy knowledge may be deficient. This study aims to evidence whether student radiographers demonstrate the same level of knowledge of anatomy after a period of time has elapsed and to correlate to approaches to learning and studying. Methodology: A repeated measures design was utilised to measure retention of anatomy knowledge for both MCQs and short-response answers to a Practical Radiographic Anatomy Examination; alpha value p < 0.05. Fifty-one students from levels 2 and 3 were retested after a time lapse of 10 and 22 months respectively. The students were not aware that their knowledge was being retested. Approaches to learning and studying were measured using the ASSIST inventory. Results: Statistical analysis found no difference in performance on MCQ assessment, in either the combined sample or levels 2 and 3 separately, from baseline to retention occasions; average retention rate being 99%. However, a statistical difference in performance on PRAE assessment was found, with level 2 experiencing a larger reduction in scores; retention rate of 67% compared to level 3 at 77%. The students perceived themselves to be principally strategic in their approach to learning and studying but no strong relationships were found when correlated to test scores. Conclusion: The student radiographers in this study demonstrated varied anatomy retention rates dependent on assessment method employed and time interval that had elapsed. It is recommended that diverse teaching and assessment strategies are adopted to encourage a deeper approach to learning and studying.

Radiodiagnosis of filled retention bronchial cysts and lung tuberculomes

International Nuclear Information System (INIS)

Gudz', A.E.

1987-01-01

Radiological semiotics of filled retention bronchial cysts in 23 patients and of lung tuberculomes in 52 is studied on the basis of the data on roentgenography, tomography and bronchography. Characteristic radiological signs of retention bronchial cysts and tuberculomes are determined. Significance of each radiological sign for differential diagnosis of filled retention bronchial cysts and lung tuberculomes is estimated

Postgraduation retention of medical students from Otago and Auckland medical programmes.

Science.gov (United States)

Shelker, William; Poole, Phillippa; Bagg, Warwick; Wood, Ian; Glue, Paul

2014-01-24

Auckland and Otago medical programmes have different methods for selecting students. This study compared postgraduate retention in New Zealand (NZ) of medical graduates from the two medical programmes, to assess whether different selection methods influenced retention. Other variables assessed included entrance category and age at graduation. Anonymised databases were created of all graduates from the Otago Faculty of Medicine (1999-2011) and the Auckland medical programme (2000-2012). Demographic and entry category data were recorded. Retention was defined as presence on the NZ Medical Register in December 2012. Risk differences (RD) were calculated to compare retention between the two medical programmes using the Mantel-Haenszel method. The influence of medical programme entrance category on retention was also tested. The influence of covariates on retaining graduates on the register was evaluated using a multiple logistic regression model. The postgraduate retention of graduates of the two medical programmes over 13 years was identical (Auckland 74.9%, Otago 73.6%, P=0.48). Retention of graduate and non-graduate entry students from both medical programmes was similar by 6 years after graduation. Age during medical school did not affect retention. University of attendance had no effect on postgraduation retention of students on the NZ Medical Register, suggesting that retention is not influenced by the different student selection methods at each programme. The data presented shows that New Zealand graduates regardless of programme completed show a similar profile in terms of retention.

Coherent oscillatory networks supporting short-term memory retention.

Science.gov (United States)

Payne, Lisa; Kounios, John

2009-01-09

Accumulating evidence suggests that top-down processes, reflected by frontal-midline theta-band (4-8 Hz) electroencephalogram (EEG) oscillations, strengthen the activation of a memory set during short-term memory (STM) retention. In addition, the amplitude of posterior alpha-band (8-13 Hz) oscillations during STM retention is thought to reflect a mechanism that protects fragile STM activations from interference by gating bottom-up sensory inputs. The present study addressed two important questions about these phenomena. First, why have previous studies not consistently found memory set-size effects on frontal-midline theta? Second, how does posterior alpha participate in STM retention? To answer these questions, large-scale network connectivity during STM retention was examined by computing EEG wavelet coherence during the retention period of a modified Sternberg task using visually-presented letters as stimuli. The results showed (a) increasing theta-band coherence between frontal-midline and left temporal-parietal sites with increasing memory load, and (b) increasing alpha-band coherence between midline parietal and left temporal/parietal sites with increasing memory load. These findings support the view that theta-band coherence, rather than amplitude, is the key factor in selective top-down strengthening of the memory set and demonstrate that posterior alpha-band oscillations associated with sensory gating are involved in STM retention by participating in the STM network.

Linking local retention, self-recruitment, and persistence in marine metapopulations

KAUST Repository

Lett, Christophe; Nguyen-Huu, Tri; Cuif, Marion; Saenz Agudelo, Pablo; Kaplan, David M.

2015-01-01

Three indices of larval retention have been used in the literature to assess the tendency for self-maintenance of local marine populations: local retention (LR), self-recruitment (SR), and relative local retention (RLR). Only one of these, LR

Evaluation of 131I retention in several adsorbers

International Nuclear Information System (INIS)

Catanoso, Marcela F.; Osso Junior, Joao Alberto

2011-01-01

Several iodine radioisotopes are used in nuclear medicine for treatment and diagnostic purposes. The radioisotope 131 I is used both in diagnosis and therapy due to its physical characteristics of decay by β - and its γ-ray emissions suitable for diagnosis. It is routinely produced at IPEN through the irradiation of TeO 2 targets in the IEA-R1m nuclear reactor. After the irradiation, the 131 I is separated by dry distillation, where the targets are put in an oven, heated at 760 deg C for 2 hours and the 131 I, volatile, is carried by an O 2 gas stream. The aim of this work was to evaluate the retention and elution of 131 I samples produced at IPEN in several adsorbers as part of a project aiming the purification of these radioisotopes, allowing the labeling of biomolecules. Samples of 131 I were used for retention and elution studies with the following adsorbers: commercial cartridges, anionic resin columns and cationic resin column. The results showed that Ag cartridges and anionic resins Dowex 1X8, Dowex 3 and IRA 400 had a great iodine retention but no elution after using specific eluents. The QMA light, acid alumina, neutral alumina and cationic resin Dowex 50WX4 showed high retention and elution and QMA plus and cationic resin Dowex 50WX8 and Dowex 50WX12 had a good retention but lower elution. Regarding to the better retention and elution, Ag cartridges and resins showed a higher percentage of iodine retention but lower elution yield and QMA light, acid and neutral alumina cartridges showed better results. (author)

Playing Super Mario 64 increases hippocampal grey matter in older adults.

Directory of Open Access Journals (Sweden)

Greg L West

Full Text Available Maintaining grey matter within the hippocampus is important for healthy cognition. Playing 3D-platform video games has previously been shown to promote grey matter in the hippocampus in younger adults. In the current study, we tested the impact of 3D-platform video game training (i.e., Super Mario 64 on grey matter in the hippocampus, cerebellum, and the dorsolateral prefrontal cortex (DLPFC of older adults. Older adults who were 55 to 75 years of age were randomized into three groups. The video game experimental group (VID; n = 8 engaged in a 3D-platform video game training over a period of 6 months. Additionally, an active control group took a series of self-directed, computerized music (piano lessons (MUS; n = 12, while a no-contact control group did not engage in any intervention (CON; n = 13. After training, a within-subject increase in grey matter within the hippocampus was significant only in the VID training group, replicating results observed in younger adults. Active control MUS training did, however, lead to a within-subject increase in the DLPFC, while both the VID and MUS training produced growth in the cerebellum. In contrast, the CON group displayed significant grey matter loss in the hippocampus, cerebellum and the DLPFC.

Playing Super Mario 64 increases hippocampal grey matter in older adults.

Science.gov (United States)

West, Greg L; Zendel, Benjamin Rich; Konishi, Kyoko; Benady-Chorney, Jessica; Bohbot, Veronique D; Peretz, Isabelle; Belleville, Sylvie

2017-01-01

Maintaining grey matter within the hippocampus is important for healthy cognition. Playing 3D-platform video games has previously been shown to promote grey matter in the hippocampus in younger adults. In the current study, we tested the impact of 3D-platform video game training (i.e., Super Mario 64) on grey matter in the hippocampus, cerebellum, and the dorsolateral prefrontal cortex (DLPFC) of older adults. Older adults who were 55 to 75 years of age were randomized into three groups. The video game experimental group (VID; n = 8) engaged in a 3D-platform video game training over a period of 6 months. Additionally, an active control group took a series of self-directed, computerized music (piano) lessons (MUS; n = 12), while a no-contact control group did not engage in any intervention (CON; n = 13). After training, a within-subject increase in grey matter within the hippocampus was significant only in the VID training group, replicating results observed in younger adults. Active control MUS training did, however, lead to a within-subject increase in the DLPFC, while both the VID and MUS training produced growth in the cerebellum. In contrast, the CON group displayed significant grey matter loss in the hippocampus, cerebellum and the DLPFC.

Algorithmic psychometrics and the scalable subject.

Science.gov (United States)

Stark, Luke

2018-04-01

Recent public controversies, ranging from the 2014 Facebook 'emotional contagion' study to psychographic data profiling by Cambridge Analytica in the 2016 American presidential election, Brexit referendum and elsewhere, signal watershed moments in which the intersecting trajectories of psychology and computer science have become matters of public concern. The entangled history of these two fields grounds the application of applied psychological techniques to digital technologies, and an investment in applying calculability to human subjectivity. Today, a quantifiable psychological subject position has been translated, via 'big data' sets and algorithmic analysis, into a model subject amenable to classification through digital media platforms. I term this position the 'scalable subject', arguing it has been shaped and made legible by algorithmic psychometrics - a broad set of affordances in digital platforms shaped by psychology and the behavioral sciences. In describing the contours of this 'scalable subject', this paper highlights the urgent need for renewed attention from STS scholars on the psy sciences, and on a computational politics attentive to psychology, emotional expression, and sociality via digital media.

Plunger with simple retention valve

International Nuclear Information System (INIS)

Fekete, A.V.

1987-01-01

This patent describes a positive displacement retention valve apparatus in which the actual flow equals the theoretical maximum flow through the retention valve. The apparatus includes, in combination, a confined fluid flow conduit, a piston adapted for reciprocal movement within the fluid flow conduit between upstream and downstream limit positions, piston reciprocating means, and pressure responsive check valve means located upstream with respect to the piston in the fluid flow conduit. The pressure responsive check valve means operable to permit fluid flow therethrough in a downstream direction toward the piston, and to preclude fluid flow therethrough in an opposite direction. The piston is composed of parts which are relatively movable with respect to one another. The piston includes a simple retention valve consisting of a plug means, a cylinder having a minimum and a maximum internal cross section flow area therein and being reciprocal within the confined fluid flow conduit, and a seat on the cylinder for the plug means. The piston reciprocating means are operatively connected to the plug means

U.S. Marine Corps Enlisted Retention: An Analysis of Stakeholder Incentives for the Retention of Tier 1 First-Term Marines

Science.gov (United States)

2014-03-01

ERTF Enlisted Retention Task Force FFM fast filling military occupational specialty FTAP first-term alignment plan FY fiscal year GT general...Planning military ( FFM ) occupational specialties that are processed through boards to ensure the retention of highly qualified Marines. Fast-filling

Root exudate as major player on soil-water retention dynamics

Science.gov (United States)

Albalasmeh, A. A.; Sweet, J. R.; Gebrenegus, T. B.; Ghezzehei, T. A.

2012-12-01

Plant roots and soil microbes release 5-60% of the entirety of photosynthetically fixed carbon in to the soil as exudates to adapt to their surrounding. There is indirect evidence suggesting that these exudates play a major role in altering the of the soil water retention properties. In this study, we used a uniformly sized (40 μm) glass beads and various concentrations (0, 2, 10, 20 and 29 g/L) of polygalacutronic acid (PGA) to mimic sandy soil and the organic exudates from plant roots, respectively. The samples were subjected to periods of drying and subsequent equilibration. At each stage, the water potential was measured using WP4C Dewpoint PotentiaMeter. The effect of root exudates on soil water retention can be attributed t at least two factors. The most widely speculated effect is through enhanced of soil aggregation. This effect is primarily due to capillary adhesion in fine pores within aggregates and is consistent was visual observation of pronounced aggregation in many rhizosphere soils. The second factor is related to osmotic effect of the exudate solution. Our observations show that the capillary effect is mostly to higher water potential regime (> -1 bar suction). Whereas the osmotic effect dominates in plant-soil relations.

Non-pharmacological modulation of cerebral white matter organization

DEFF Research Database (Denmark)

Kristensen, Tina D; Mandl, Rene C W; Jepsen, Jens R M

2018-01-01

OBJECTIVE: Neuroplasticity is a well-described phenomenon, but effects of non-pharmacological interventions on white matter (WM) are unclear. Here we review associations between active non-pharmacological interventions and WM organization in healthy subjects and in psychiatric patients. METHOD...

Aerosol retention in the flooded steam generator bundle during SGTR

International Nuclear Information System (INIS)

Lind, Terttaliisa; Dehbi, Abdel; Guentay, Salih

2011-01-01

Research highlights: → High retention of aerosol particles in a steam generator bundle flooded with water. → Increasing particle inertia, i.e., particle size and velocity, increases retention. → Much higher retention of aerosol particles in the steam generator bundle flooded with water than in a dry bundle. → Much higher retention of aerosol particles in the steam generator bundle than in a bare pool. → Bare pool models have to be adapted to be applicable for flooded bundles. - Abstract: A steam generator tube rupture in a pressurized water reactor may cause accidental release of radioactive particles into the environment. Its specific significance is in its potential to bypass the containment thereby providing a direct pathway of the radioactivity from the primary circuit to the environment. Under certain severe accident scenarios, the steam generator bundle may be flooded with water. In addition, some severe accident management procedures are designed to minimize the release of radioactivity into the environment by flooding the defective steam generator secondary side with water when the steam generator has dried out. To extend our understanding of the particle retention phenomena in the flooded steam generator bundle, tests were conducted in the ARTIST and ARTIST II programs to determine the effect of different parameters on particle retention. The effects of particle type (spherical or agglomerate), particle size, gas mass flow rate, and the break submergence on particle retention were investigated. Results can be summarized as follows: increasing particle inertia was found to increase retention in the flooded bundle. Particle shape, i.e., agglomerate or spherical structure, did not affect retention significantly. Even with a very low submergence, 0.3 m above the tube break, significant aerosol retention took place underlining the importance of the jet-bundle interactions close to the tube break. Droplets were entrained from the water surface with

The research of condensed matter physics by using intense proton accelerator

International Nuclear Information System (INIS)

Endoh, Yasuo

1990-01-01

The present article covers the application of intense protons to basic condensed matter physics. Major recent neutron scattering activities in condensed matter physics are first outlined, emphasizing the fact that the contribution of accelerator base science has a tremendous impact on this basic science. Application of spallation neutrons to condensed matter physics is discussed in relation to such subjects as high energy (epithermal) excitations and small angle neutron scattering. Then the specific subject of high Tc superconductor is addressed, focusing on how neutrons as well as muons provide experimental results that serve significantly in exploring the mechanism of exotic high Tc superconductivity. Techniques for neutron polarization must be developed in the future. The neutron spin reflectivity ratio has been shown to be a sensitive probe of surface depth profile of magnetization. Another new method is neutron depolarization to probe bulk magnetic induction throughout a slab which neutrons pass through. (N.K.)

Liquid Effluent Retention Facility

Data.gov (United States)

Federal Laboratory Consortium — The Liquid Effluent Retention Facility (LERF) is located in the central part of the Hanford Site. LERF is permitted by the State of Washington and has three liquid...

Faculty Personality: A Factor of Student Retention

Science.gov (United States)

Shaw, Cassandra S.; Wu, Xiaodong; Irwin, Kathleen C.; Patrizi, L. A. Chad

2016-01-01

The purpose of this study was to determine the relationship between student retention and faculty personality as it was hypothesized that faculty personality has an effect on student retention. The methodology adopted for this study was quantitative and in two parts 1) using linear regression models to examine the impact or causality of faculty…

Towards high-density matter with relativistic heavy-ion collisions

International Nuclear Information System (INIS)

Nagamiya, Shoji.

1990-04-01

Recent progress in nucleus-nucleus collisions at BNL and CERN suggests a hint that the formation of high-density nuclear matter could be possible with relativistic heavy-ion beams. What is the maximum density that can be achieved by heavy-ion collisions? Are there data which show evidence or hints on the formation of high density matter? Why is the research of high-density interesting? How about the future possibilities on this subject? These points are discussed. (author)

Assessment of patency capsule retention using MR diffusion-weighted imaging

Energy Technology Data Exchange (ETDEWEB)

Klang, Eyal; Rozendorn, Noa; Amitai, Michal Marianne [Sheba Medical Center, Department of Diagnostic Imaging, Ramat Gan (Israel); Tel Aviv University, Sackler Faculty of Medicine, Tel Aviv (Israel); Kopylov, Uri; Ben-Horin, Shomron; Lahat, Adi; Yablecovitch, Doron; Eliakim, Rami [Tel Aviv University, Sackler Faculty of Medicine, Tel Aviv (Israel); Sheba Medical Center, Department of Gastroenterology, Ramat Gan (Israel)

2017-12-15

Evaluate the ability of MR diffusion-weighted imaging (DWI) to predict patency capsule retention in Crohn's disease (CD). Clinical and imaging data were prospectively reviewed for 80 CD patients following patency capsule administration and MR-DWI under institutional review board (IRB) approval with informed consent. Two radiologists separately assessed the presence/absence of restricted diffusion in the distal ileum. Apparent diffusion coefficients (ADC) from three regions of interest on the ileal wall were averaged. The association between restricted diffusion and retention, and sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated. Ability of ADC to predict retention was assessed with receiver operating characteristic (ROC) curve analysis. Restricted diffusion in the distal ileum was associated with capsule retention (p = 0.001, p < 0.0001). Sensitivity, specificity, PPV and NPV of restricted diffusion for capsule retention were 100.0%, 46.2%, 30.0%, 100% and 100.0%, 56.9%, 34.9%, 100%, respectively, for two radiologists. Accuracy of ADC to predict retention was high (area under the curve = 0.851, p < 0.0001). An ADC of 1.47 mm{sup 2}/s showed 90.0% sensitivity and 50.0% specificity for retention. Sensitivity and NPV of restricted diffusion for patency capsule retention were 100%, suggesting that DWI may predict gastrointestinal tract capability to pass video camera endoscopy. (orig.)

Assessment of patency capsule retention using MR diffusion-weighted imaging

International Nuclear Information System (INIS)

Klang, Eyal; Rozendorn, Noa; Amitai, Michal Marianne; Kopylov, Uri; Ben-Horin, Shomron; Lahat, Adi; Yablecovitch, Doron; Eliakim, Rami

2017-01-01

Evaluate the ability of MR diffusion-weighted imaging (DWI) to predict patency capsule retention in Crohn's disease (CD). Clinical and imaging data were prospectively reviewed for 80 CD patients following patency capsule administration and MR-DWI under institutional review board (IRB) approval with informed consent. Two radiologists separately assessed the presence/absence of restricted diffusion in the distal ileum. Apparent diffusion coefficients (ADC) from three regions of interest on the ileal wall were averaged. The association between restricted diffusion and retention, and sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated. Ability of ADC to predict retention was assessed with receiver operating characteristic (ROC) curve analysis. Restricted diffusion in the distal ileum was associated with capsule retention (p = 0.001, p < 0.0001). Sensitivity, specificity, PPV and NPV of restricted diffusion for capsule retention were 100.0%, 46.2%, 30.0%, 100% and 100.0%, 56.9%, 34.9%, 100%, respectively, for two radiologists. Accuracy of ADC to predict retention was high (area under the curve = 0.851, p < 0.0001). An ADC of 1.47 mm 2 /s showed 90.0% sensitivity and 50.0% specificity for retention. Sensitivity and NPV of restricted diffusion for patency capsule retention were 100%, suggesting that DWI may predict gastrointestinal tract capability to pass video camera endoscopy. (orig.)

“To be or not to be Retained … That’s the Question!” Retention, Self-esteem, Self-concept, Achievement Goals, and Grades

Science.gov (United States)

Peixoto, Francisco; Monteiro, Vera; Mata, Lourdes; Sanches, Cristina; Pipa, Joana; Almeida, Leandro S.

2016-01-01

Keeping students back in the same grade – retention – has always been a controversial issue in Education, with some defending it as a beneficial remedial practice and others arguing against its detrimental effects. This paper undertakes an analysis of this issue, focusing on the differences in student motivation and self-related variables according to their retention related status, and the interrelationship between retention and these variables. The participants were 695 students selected from two cohorts (5th and 7th graders) of a larger group of students followed over a 3-year project. The students were assigned to four groups according to their retention-related status over time: (1) students with past and recent retention; (2) students with past but no recent retention; (3) students with no past but recent retention; (4) students with no past or recent retention. Measures of achievement goal orientations, self-concept, self-esteem, importance given to school subjects and Grade Point Average (GPA) were collected for all students. Repeated measures MANCOVA analyses were carried out showing group differences in self-esteem, academic self-concept, importance attributed to academic competencies, task and avoidance orientation and academic achievement. To attain a deeper understanding of these results and to identify profiles across variables, a cluster analysis based on achievement goals was conducted and four clusters were identified. Students who were retained at the end of the school year are mainly represented in clusters with less adaptive motivational profiles and almost absent from clusters exhibiting more adaptive ones. Findings highlight that retention leaves a significant mark that remains even when students recover academic achievement and retention is in the distant past. This is reflected in the low academic self-concept as well as in the devaluation of academic competencies and in the avoidance orientation which, taken together, can undermine

Retention of Millennial Employees in the Army Acquisition Workforce

Science.gov (United States)

2016-04-07

the job market affects the retention of all generations of employees, not only Millennials (Sorenson & Garman, 2013, p. 3). If the employees’ needs...having more at stake rather than having a specific fundamental difference in how they approach staying in a job . Millennial Retention Factors...that personal characteristics, plus preferred job characteristics, plus quality of work experience, equals high employee retention , as depicted in

NONEQUILIBRIUM SULFUR CAPTURE AND RETENTION IN AN AIR COOLED SLAGGING COAL COMBUSTOR

International Nuclear Information System (INIS)

Dr. Bert Zauderer

1999-01-01

Calcium oxide injected in a slagging combustor reacts with the sulfur from coal combustion to form sulfur-bearing particles. They are deposited on the liquid slag layer on the combustor wall. Due to the low solubility of sulfur in slag, slag must be rapidly drained from the combustor to limit sulfur gas re-evolution. Analysis indicated that slag mass flow rates in excess of 400 lb/hr should limit sulfur re-evolution. The objective of this 42-month project was to perform a series of tests to determine the factors that control the retention of the sulfur in the slag. 36 days of testing on the combustor were completed prior to the end of this reporting period, 12/31/98. This compares with 16 tests required in the original project plan. Combustor tests in early 1997 with high (37%) ash, Indian coal confirmed that high slag mass flow rates of about 500 lb/hr resulted in retention in the slag of up to 20% of the injected sulfur content mineral matter. To further increase the slag flow rate, rice husks, which contain 20% ash, and rice husk char, which contain 70% ash, were co-fired with coal in the combustor. A series of 13 combustor tests were performed in fourth quarter of 1997 and a further 6 tests were performed in January 1998 and in the summer of 1998. The test objective was to achieve slag flow rates between 500 and 1,000 lb/hr. Due to the very low bulk density of rice husk, compared to pulverized coal, almost the entire test effort focused on developing methods for feeding the rice husks into combustor. In the last test of December 1997, a peak mineral matter, injection rate of 592 lb/hr was briefly achieved by injection of coal, rice husk char, gypsum, and limestone into the combustor. However, no significant sulfur concentration was measured in the slag removed from the combustor. The peak injection rate reached with biomass in the 1997 tests was 310 lb/hr with rice husk, and 584 lb/hr with rice husk char

Career satisfaction and retention risk among Wisconsin internists.

Science.gov (United States)

Giriyappa, Pradeep; Sullivan, Kandis K

2009-09-01

Physician career satisfaction has been studied extensively, but career satisfaction as it relates to retention is less well studied. The objective was to assess the relationship between career satisfaction and retention in primary care internal medicine physicians in Wisconsin. In this descriptive quantitative study, survey data was assessed for correlations between career satisfaction, risk to retention, and demographics. The survey included 1231 primary care internal medicine physicians in the Wisconsin Medical Directory (2007). Responses were measured by career satisfaction variables, and demographics and retention variables for the purpose of correlations and regression analysis. Survey responses included 573 physicians. An additional 85 physicians were disqualified. The final survey group included 1146 physicians for a response rate of 50%. A total of 116 physicians (20.2%) reported anticipating leaving their current position, 84 (14.7%) physicians reported anticipating leaving the career of medicine. Identified at risk for retention were 144 (25.1%) physicians. The lowest career satisfaction scores were reported in the areas of compensation (3.19) and practice (3.42) on a scale of 1 (very dissatisfied) to 5 (very satisfied). The highest correlations to retention were associated with practice, followed by compensation satisfaction. The level of significance for this study was identified as 0.05, and the P-value was 0.000. The study findings reveal a significant risk to the stability of continuity of care for patients, and may cost Wisconsin health care organizations more than $35 million in recruitment costs to replace departing physicians.

Testing and evaluation of existing techniques for identifying uptakes and measuring retention of uranium in mill workers

International Nuclear Information System (INIS)

1983-03-01

Preliminary tests and evaluations of existing bio-analytical techniques for identifying uptakes and measuring retention of uranium in mill workers were made at two uranium mills. Urinalysis tests were found to be more reliable indicators of uranium uptakes than personal air sampling. Static air samples were not found to be good indicators of personal uptakes. In vivo measurements of uranium in lung were successfully carried out in the presence of high and fluctuating background radiation. Interference from external contamination was common during end of shift measurements. A full scale study to evaluate model parameters for the uptake, retention and elimination of uranium should include, in addition to the above techniques, particle size determination of airborne uranium, solubility in simulated lung fluid, uranium analysis in faeces and bone and minute volume measurements for each subject

Assessing Potential Additional PFAS Retention Processes in the Subsurface

Science.gov (United States)

Brusseau, M. L.

2017-12-01

Understanding the transport and fate of per- and poly-fluorinated alkyl substances (PFASs) in the subsurface is critical for accurate risk assessments and design of effective remedial actions. Current conceptual and mathematical models are based on an assumption that solid-phase adsorption is the sole source of retention for PFASs. However, additional retention processes may be relevant for PFAS compounds in vadose-zone systems and in source zones that contain trapped immiscible organic liquids. These include adsorption at the air-water interface, partitioning to the soil atmosphere, adsorption at the NAPL-water interface, and absorption by NAPL. A multi-process retention model is proposed to account for these potential additional sources of PFAS retardation. An initial assessment of the relative magnitudes and significance of these retention processes was conducted for three representative PFASs, perfluorooctanoic acid (PFOA), perfluorooctane sulfonate (PFOS), and 8:2 fluorotelomer alcohol (FTOH). Data collected from the literature were used to determine measured or estimated values for the relevant distribution coefficients, which were in turn used to calculate retardation factors for a representative porous medium. Adsorption at the air-water interface was shown to be a primary source of retention for PFOA and PFOS, contributing approximately 80% of total retardation. Adsorption to NAPL-water interfaces and absorption by bulk NAPL were also shown to be significant sources of retention for PFOS and PFOA. The latter process was the predominant source of retention for 8:2 FTOH, contributing 98% of total retardation. These results indicate that we may anticipate significant retention of PFASs by these additional processes. In such cases, retardation of PFASs in source areas may be significantly greater than what is typically estimated based on the standard assumption of solid-phase adsorption as the sole retention mechanism. This has significant ramifications for

The Influence of a Humectant on the Retention by Humans of Solanesol from Cigarette Smoke (Part 2, Glycerin

Directory of Open Access Journals (Sweden)

Moldoveanu SC

2014-12-01

Full Text Available Two common humectants are used as additives in the cigarette manufacturing process, propylene glycol (PG and glycerin. The humectants may influence the deposition of cigarette smoke in the human respiratory tract by affecting the hygroscopic properties and growth of smoke particles. This study examines the influence of glycerin addition on the retention of solanesol by smokers. The influence of PG addition has been previously reported (7. The first cigarette used in the study (control was a commercially available brand containing no additives in the blend (with a measured level of glycerin of 0.19%. The other cigarette (test had an identical tobacco blend to the control, but had 2.3% added glycerin. The construction of the cigarette with 2.3% glycerin (test was selected to match as closely as possible the ‘tar’ (as measured by Federal Trade Commission regimen, pressure drop (open and closed, and nicotine level of the commercial cigarette (control. Twelve smokers evaluated both products. The sample collection was performed using three cigarettes smoked within one hour. Each human subject smoked the control cigarette and then the test cigarette in two separate sessions. The exhaled smoke was collected using a vacuum assisted procedure designed to avoid strain in exhaling, and solanesol was analyzed using an high performance liquid chromatography (HPLC technique. The cigarette butts from the smokers were collected and also analyzed for solanesol. The results obtained for the cigarette butts from the smokers were used to calculate the level of solanesol in the smoke delivered to the human subject, based on calibration curves. These curves were generated separately by analyzing the solanesol in smoke and in the cigarette butts obtained by machine smoking under different puffing regimes. Knowing the levels of delivered amount of solanesol and that in the exhaled smoke it was possible to calculate the retention of this compound from mainstream

Towards a chromatographic similarity index to establish localised quantitative structure-retention relationships for retention prediction. II Use of Tanimoto similarity index in ion chromatography.

Science.gov (United States)

Park, Soo Hyun; Talebi, Mohammad; Amos, Ruth I J; Tyteca, Eva; Haddad, Paul R; Szucs, Roman; Pohl, Christopher A; Dolan, John W

2017-11-10

Quantitative Structure-Retention Relationships (QSRR) are used to predict retention times of compounds based only on their chemical structures encoded by molecular descriptors. The main concern in QSRR modelling is to build models with high predictive power, allowing reliable retention prediction for the unknown compounds across the chromatographic space. With the aim of enhancing the prediction power of the models, in this work, our previously proposed QSRR modelling approach called "federation of local models" is extended in ion chromatography to predict retention times of unknown ions, where a local model for each target ion (unknown) is created using only structurally similar ions from the dataset. A Tanimoto similarity (TS) score was utilised as a measure of structural similarity and training sets were developed by including ions that were similar to the target ion, as defined by a threshold value. The prediction of retention parameters (a- and b-values) in the linear solvent strength (LSS) model in ion chromatography, log k=a - blog[eluent], allows the prediction of retention times under all eluent concentrations. The QSRR models for a- and b-values were developed by a genetic algorithm-partial least squares method using the retention data of inorganic and small organic anions and larger organic cations (molecular mass up to 507) on four Thermo Fisher Scientific columns (AS20, AS19, AS11HC and CS17). The corresponding predicted retention times were calculated by fitting the predicted a- and b-values of the models into the LSS model equation. The predicted retention times were also plotted against the experimental values to evaluate the goodness of fit and the predictive power of the models. The application of a TS threshold of 0.6 was found to successfully produce predictive and reliable QSRR models (Q ext(F2) 2 >0.8 and Mean Absolute Error<0.1), and hence accurate retention time predictions with an average Mean Absolute Error of 0.2min. Crown Copyright �

Assessing the HIV Care Continuum in Latin America: progress in clinical retention, cART use and viral suppression

Science.gov (United States)

Rebeiro, Peter F; Cesar, Carina; Shepherd, Bryan E; De Boni, Raquel B; Cortés, Claudia P; Rodriguez, Fernanda; Belaunzarán-Zamudio, Pablo; Pape, Jean W; Padgett, Denis; Hoces, Daniel; McGowan, Catherine C; Cahn, Pedro

2016-01-01

Introduction We assessed trends in HIV Care Continuum outcomes associated with delayed disease progression and reduced transmission within a large Latin American cohort over a decade: clinical retention, combination antiretroviral therapy (cART) use and viral suppression (VS). Methods Adults from Caribbean, Central and South America network for HIV epidemiology clinical cohorts in seven countries contributed data between 2003 and 2012. Retention was defined as two or more HIV care visits annually, >90 days apart. cART was defined as prescription of three or more antiretroviral agents annually. VS was defined as HIV-1 RNA <200 copies/mL at last measurement annually. cART and VS denominators were subjects with at least one visit annually. Multivariable modified Poisson regression was used to assess temporal trends and examine associations between age, sex, HIV transmission mode, cohort, calendar year and time in care. Results Among 18,799 individuals in retention analyses, 14,380 in cART analyses and 13,330 in VS analyses, differences existed between those meeting indicator definitions versus those not by most characteristics. Retention, cART and VS significantly improved from 2003 to 2012 (63 to 77%, 74 to 91% and 53 to 82%, respectively; p<0.05, each). Female sex (risk ratio (RR)=0.97 vs. males) and injection drug use as HIV transmission mode (RR=0.83 vs. male sexual contact with males (MSM)) were significantly associated with lower retention, but unrelated with cART or VS. MSM (RR=0.96) significantly decreased the probability of cART compared with heterosexual transmission. Conclusions HIV Care Continuum outcomes improved over time in Latin America, though disparities for vulnerable groups remain. Efforts must be made to increase retention, cART and VS, while engaging in additional research to sustain progress in these settings. PMID:27065108

Potential Water Retention Capacity as a Factor in Silage Effluent Control: Experiments with High Moisture By-product Feedstuffs.

Science.gov (United States)

Razak, Okine Abdul; Masaaki, Hanada; Yimamu, Aibibula; Meiji, Okamoto

2012-04-01

The role of moisture absorptive capacity of pre-silage material and its relationship with silage effluent in high moisture by-product feedstuffs (HMBF) is assessed. The term water retention capacity which is sometimes used in explaining the rate of effluent control in ensilage may be inadequate, since it accounts exclusively for the capacity of an absorbent incorporated into a pre-silage material prior to ensiling, without consideration to how much the pre-silage material can release. A new terminology, 'potential water retention capacity' (PWRC), which attempts to address this shortcoming, is proposed. Data were pooled from a series of experiments conducted separately over a period of five years using laboratory silos with four categories of agro by-products (n = 27) with differing moisture contents (highest 96.9%, lowest 78.1% in fresh matter, respectively), and their silages (n = 81). These were from a vegetable source (Daikon, Raphanus sativus), a root tuber source (potato pulp), a fruit source (apple pomace) and a cereal source (brewer's grain), respectively. The pre-silage materials were adjusted with dry in-silo absorbents consisting wheat straw, wheat or rice bran, beet pulp and bean stalks. The pooled mean for the moisture contents of all pre-silage materials was 78.3% (±10.3). Silage effluent decreased (p<0.01), with increase in PWRC of pre-silage material. The theoretical moisture content and PWRC of pre-silage material necessary to stem effluent flow completely in HMBF silage was 69.1% and 82.9 g/100 g in fresh matter, respectively. The high correlation (r = 0.76) between PWRC of ensiled material and silage effluent indicated that the latter is an important factor in silage-effluent relationship.

Ambient particulate matter as a risk factor for suicide.

Science.gov (United States)

Kim, Changsoo; Jung, Sang Hyuk; Kang, Dae Ryong; Kim, Hyeon Chang; Moon, Ki Tae; Hur, Nam Wook; Shin, Dong Chun; Suh, Il

2010-09-01

The authors assessed the relationship between exposure to ambient particulate matter and suicide in urban settings during a 1-year period. The association between particulate matter and suicide was determined using a time-stratified case-crossover approach in which subjects served as their own controls. All suicide cases (4,341) in 2004 that occurred in seven cities in the Republic of Korea were included. Hourly mean concentrations of particulate matter suicide risk associated with an interquartile range increase in particulate matter was determined by conditional logistic regression analysis after adjusting for national holidays and meteorological factors. Subgroup analysis was performed after stratification by underlying disease (cardiovascular disease, diabetes mellitus, chronic obstructive pulmonary disease, cancer, and psychiatric illness). The largest associations were a 9.0% increase (95% CI=2.4-16.1) and a 10.1% (95% CI=2.0-19.0) increase in suicide risk related to an interquartile range increase in particulate matter suicide) and particulate matter suicide), respectively. Among individuals with cardiovascular disease, a significant association between particulate matter suicide) and suicide was observed (18.9%; 95% CI=3.2-37.0). Conclusions: A transient increase in particulate matter was associated with increased suicide risk, especially for individuals with preexisting cardiovascular disease.

Biofilm roughness determines Cryptosporidium parvum retention in environmental biofilms.

Science.gov (United States)

DiCesare, E A Wolyniak; Hargreaves, B R; Jellison, K L

2012-06-01

The genus Cryptosporidium is a group of waterborne protozoan parasites that have been implicated in significant outbreaks of gastrointestinal infections throughout the world. Biofilms trap these pathogens and can contaminate water supplies through subsequent release. Biofilm microbial assemblages were collected seasonally from three streams in eastern Pennsylvania and used to grow biofilms in laboratory microcosms. Daily oocyst counts in the influx and efflux flow allowed the calculation of daily oocyst retention in the biofilm. Following the removal of oocysts from the influx water, oocyst attachment to the biofilm declined to an equilibrium state within 5 days that was sustained for at least 25 days. Varying the oocyst loading rate for the system showed that biofilm retention could be saturated, suggesting that discrete binding sites determined the maximum number of oocysts retained. Oocyst retention varied seasonally but was consistent across all three sites; however, seasonal oocyst retention was not consistent across years at the same site. No correlation between oocyst attachment and any measured water quality parameter was found. However, oocyst retention was strongly correlated with biofilm surface roughness and roughness varied among seasons and across years. We hypothesize that biofilm roughness and oocyst retention are dependent on environmentally driven changes in the biofilm community rather than directly on water quality conditions. It is important to understand oocyst transport dynamics to reduce risks of human infection. Better understanding of factors controlling biofilm retention of oocysts should improve our understanding of oocyst transport at different scales.

White matter integrity as a predictor of response to treatment in first episode psychosis.

Science.gov (United States)

Reis Marques, Tiago; Taylor, Heather; Chaddock, Chris; Dell'acqua, Flavio; Handley, Rowena; Reinders, A A T Simone; Mondelli, Valeria; Bonaccorso, Stefania; Diforti, Marta; Simmons, Andrew; David, Anthony S; Murray, Robin M; Pariante, Carmine M; Kapur, Shitij; Dazzan, Paola

2014-01-01

The integrity of brain white matter connections is central to a patient's ability to respond to pharmacological interventions. This study tested this hypothesis using a specific measure of white matter integrity, and examining its relationship to treatment response using a prospective design in patients within their first episode of psychosis. Diffusion tensor imaging data were acquired in 63 patients with first episode psychosis and 52 healthy control subjects (baseline). Response was assessed after 12 weeks and patients were classified as responders or non-responders according to treatment outcome. At this second time-point, they also underwent a second diffusion tensor imaging scan. Tract-based spatial statistics were used to assess fractional anisotropy as a marker of white matter integrity. At baseline, non-responders showed lower fractional anisotropy than both responders and healthy control subjects (P psychosis. These data, together with earlier findings on cortical grey matter, suggest that grey and white matter integrity at the start of treatment is an important moderator of response to antipsychotics. These findings can inform patient stratification to anticipate care needs, and raise the possibility that antipsychotics may restore white matter integrity as part of the therapeutic response.

Soil Cd, Cr, Cu, Ni, Pb and Zn sorption and retention models using SVM: Variable selection and competitive model.

Science.gov (United States)

González Costa, J J; Reigosa, M J; Matías, J M; Covelo, E F

2017-09-01

The aim of this study was to model the sorption and retention of Cd, Cu, Ni, Pb and Zn in soils. To that extent, the sorption and retention of these metals were studied and the soil characterization was performed separately. Multiple stepwise regression was used to produce multivariate models with linear techniques and with support vector machines, all of which included 15 explanatory variables characterizing soils. When the R-squared values are represented, two different groups are noticed. Cr, Cu and Pb sorption and retention show a higher R-squared; the most explanatory variables being humified organic matter, Al oxides and, in some cases, cation-exchange capacity (CEC). The other group of metals (Cd, Ni and Zn) shows a lower R-squared, and clays are the most explanatory variables, including a percentage of vermiculite and slime. In some cases, quartz, plagioclase or hematite percentages also show some explanatory capacity. Support Vector Machine (SVM) regression shows that the different models are not as regular as in multiple regression in terms of number of variables, the regression for nickel adsorption being the one with the highest number of variables in its optimal model. On the other hand, there are cases where the most explanatory variables are the same for two metals, as it happens with Cd and Cr adsorption. A similar adsorption mechanism is thus postulated. These patterns of the introduction of variables in the model allow us to create explainability sequences. Those which are the most similar to the selectivity sequences obtained by Covelo (2005) are Mn oxides in multiple regression and change capacity in SVM. Among all the variables, the only one that is explanatory for all the metals after applying the maximum parsimony principle is the percentage of sand in the retention process. In the competitive model arising from the aforementioned sequences, the most intense competitiveness for the adsorption and retention of different metals appears between

Safeguards Workforce Repatriation, Retention and Utilization

Energy Technology Data Exchange (ETDEWEB)

Gallucci, Nicholas [Brookhaven National Lab. (BNL), Upton, NY (United States); Poe, Sarah [Brookhaven National Lab. (BNL), Upton, NY (United States)

2015-10-01

Brookhaven National Laboratory was tasked by NA-241 to assess the transition of former IAEA employees back to the United States, investigating the rate of retention and overall smoothness of the repatriation process among returning safeguards professionals. Upon conducting several phone interviews, study authors found that the repatriation process went smoothly for the vast majority and that workforce retention was high. However, several respondents expressed irritation over the minimal extent to which their safeguards expertise had been leveraged in their current positions. This sentiment was pervasive enough to prompt a follow-on study focusing on questions relating to the utilization rather than the retention of safeguards professionals. A second, web-based survey was conducted, soliciting responses from a larger sample pool. Results suggest that the safeguards workforce may be oversaturated, and that young professionals returning to the United States from Agency positions may soon encounter difficulties finding jobs in the field.

Active Learning: 101 Strategies To Teach Any Subject.

Science.gov (United States)

Silberman, Mel

This book contains specific, practical strategies that can be used for almost any subject matters to promote active learning. It brings together in one source a comprehensive collection of instructional strategies, with ways to get students to be active from the beginning through activities that build teamwork and get students thinking about the…

The non-linear dynamics of vortices subjected to correlated and ...

Indian Academy of Sciences (India)

Understanding the dynamics of vortex matter subjected to random and .... The authors thank the support provided by a joint grant (USIF-funds) from the ... of Naval Research and the Department of Science and Technology, Government of India ...

Relationship between management styles and nurses' retention at ...

African Journals Online (AJOL)

Conclusion: Management style and nurses' retention were significantly interrelated in terms of exploitative/authoritative management style. Recommendation, the researcher recommended that hospital leaders should plan and implement effective strategies to promote nurse retention. This can be done through creating a ...

Retention of gaseous isotopes

International Nuclear Information System (INIS)

Yarbro, O.O.; Mailen, J.C.; Stephenson, M.J.

1977-01-01

Retention of gaseous fission products during fuel reprocessing has, in the past, been limited to a modest retention of 131 I when processing fuels decayed less than about 180 days. The projected rapid growth of the nuclear power industry along with a desire to minimize environmental effects is leading to the reassessment of requirements for retention of gaseous fission products, including 131 I, 129 I, 85 Kr, 3 H, and 14 C. Starting in the late 1960s, a significant part of the LMFBR reprocessing development program has been devoted to understanding the behavior of gaseous fission products in plant process and effluent streams and the development of advanced systems for their removal. Systems for iodine control include methods for evolving up to 99% of the iodine from dissolver solutions to minimize its introduction and distribution throughout downstream equipment. An aqueous scrubbing system (Iodox) using 20 M HNO 3 as the scrubbing media effectively removes all significant iodine forms from off-gas streams while handling the kilogram quantities of iodine present in head-end and dissolver off-gas streams. Silver zeolite is very effective for removing iodine forms at low concentration from the larger-volume plant off-gas streams. Removal of iodine from plant liquid effluents by solid sorbents either prior to or following final vaporization appears feasible. Krypton is effectively released during dissolution and can be removed from the relatively small volume head-end and dissolver off-gas stream. Two methods appear applicable for removal and concentration of krypton: (1) selective absorption in fluorocarbons, and (2) cryogenic absorption in liquid nitrogen. The fluorocarbon absorption process appears to be rather tolerant of the normal contaminants (H 2 O, CO 2 , NOsub(x), and organics) present in typical reprocessing plant off-gas whereas the cryogenic system requires an extensive feed gas pretreatment system. Retention of tritium in a reprocessing plant is

16 CFR 1203.16 - Dynamic strength of retention system test.

Science.gov (United States)

2010-01-01

... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Dynamic strength of retention system test.... (2) The retention system strength test equipment shall consist of a dynamic impact apparatus that... stirrup. (2) Mark the pre-test position of the retention system, with the entire dynamic test apparatus...

A modelling study of long term green roof retention performance.

Science.gov (United States)

Stovin, Virginia; Poë, Simon; Berretta, Christian

2013-12-15

This paper outlines the development of a conceptual hydrological flux model for the long term continuous simulation of runoff and drought risk for green roof systems. A green roof's retention capacity depends upon its physical configuration, but it is also strongly influenced by local climatic controls, including the rainfall characteristics and the restoration of retention capacity associated with evapotranspiration during dry weather periods. The model includes a function that links evapotranspiration rates to substrate moisture content, and is validated against observed runoff data. The model's application to typical extensive green roof configurations is demonstrated with reference to four UK locations characterised by contrasting climatic regimes, using 30-year rainfall time-series inputs at hourly simulation time steps. It is shown that retention performance is dependent upon local climatic conditions. Volumetric retention ranges from 0.19 (cool, wet climate) to 0.59 (warm, dry climate). Per event retention is also considered, and it is demonstrated that retention performance decreases significantly when high return period events are considered in isolation. For example, in Sheffield the median per-event retention is 1.00 (many small events), but the median retention for events exceeding a 1 in 1 yr return period threshold is only 0.10. The simulation tool also provides useful information about the likelihood of drought periods, for which irrigation may be required. A sensitivity study suggests that green roofs with reduced moisture-holding capacity and/or low evapotranspiration rates will tend to offer reduced levels of retention, whilst high moisture-holding capacity and low evapotranspiration rates offer the strongest drought resistance. Copyright © 2013 Elsevier Ltd. All rights reserved.

Open problems in condensed matter physics, 1987

International Nuclear Information System (INIS)

Falicov, L.M.

1988-08-01

The 1970's and 1980's can be considered the third stage in the explosive development of condensed matter physics. After the very intensive research of the 1930's and 1940's, which followed the formulation of quantum mechanics, and the path-breaking activity of the 1950's and 1960's, the problems being faced now are much more complex and not always susceptible to simple modelling. The (subjectively) open problems discussed here are: high temperature superconductivity, its properties and the possible new mechanisms which lead to it; the integral and fractional quantum Hall effects; new forms of order in condensed-matter systems; the physics of disorder, especially the problem of spin glasses; the physics of complex anisotropic systems; the theoretical prediction of stable and metastable states of matter; the physics of highly correlated states (heavy fermions); the physics of artificially made structures, in particular heterostructures and highly metastable states of matter; the determination of the microscopic structure of surfaces; and chaos and highly nonlinear phnomena. 82 refs

A theoretical model of job retention for home health care nurses.

Science.gov (United States)

Ellenbecker, Carol Hall

2004-08-01

Predicted severe nursing shortages and an increasing demand for home health care services have made the retention of experienced, qualified nursing staff a priority for health care organizations. The purpose of this paper is to describe a theoretical model of job retention for home health care nurses. The theoretical model is an integration of the findings of empirical research related to intent to stay and retention, components of Neal's theory of home health care nursing practice and findings from earlier work to develop an instrument to measure home health care nurses' job satisfaction. The theoretical model identifies antecedents to job satisfaction of home health care nurses. The antecedents are intrinsic and extrinsic job characteristics. The model also proposes that job satisfaction is directly related to retention and indirectly related to retention though intent to stay. Individual nurse characteristics are indirectly related to retention through intent to stay. The individual characteristic of tenure is indirectly related to retention through autonomy, as an intrinsic characteristic of job satisfaction, and intent to stay. The proposed model can be used to guide research that explores gaps in knowledge about intent to stay and retention among home health care nurses.

Primordial Regular Black Holes: Thermodynamics and Dark Matter

Directory of Open Access Journals (Sweden)

José Antonio de Freitas Pacheco

2018-05-01

Full Text Available The possibility that dark matter particles could be constituted by extreme regular primordial black holes is discussed. Extreme black holes have zero surface temperature, and are not subjected to the Hawking evaporation process. Assuming that the common horizon radius of these black holes is fixed by the minimum distance that is derived from the Riemann invariant computed from loop quantum gravity, the masses of these non-singular stable black holes are of the order of the Planck mass. However, if they are formed just after inflation, during reheating, their initial masses are about six orders of magnitude higher. After a short period of growth by the accretion of relativistic matter, they evaporate until reaching the extreme solution. Only a fraction of 3.8 × 10−22 of relativistic matter is required to be converted into primordial black holes (PBHs in order to explain the present abundance of dark matter particles.

Emission of Electromagnetic Waves through Medium of Matter Waves, Correlation between Wavelengths and Temperatures in Radiation Series of Hydrogen

Czech Academy of Sciences Publication Activity Database

Pekárek, Viktor

2002-01-01

Roč. 47, č. 2 (2002), s. 139-149 ISSN 0001-7043 Institutional research plan: CEZ:AV0Z2057903 Keywords : Matter waves * interference and surges of matter waves Subject RIV: BM - Solid Matter Physics ; Magnetism

Registered nurse retention strategies in nursing homes: a two-factor perspective.

Science.gov (United States)

Hunt, Selina R; Probst, Janice C; Haddock, Kathlyn S; Moran, Robert; Baker, Samuel L; Anderson, Ruth A; Corazzini, Kirsten

2012-01-01

As the American population ages and the proportion of individuals over the age of 65 expands, the demand for high-quality nursing home care will increase. However, nursing workforce instability threatens care quality and sustainability in this sector. Despite increasing attention to nursing home staff turnover, far less is known about registered nurse (RN) retention. In this study, the relationships between retention strategies, employee benefits, features of the practice environment, and RN retention were explored. Further, the utility of Herzberg's two-factor theory of motivation as a framework for nursing home retention studies was evaluated. This study was a secondary analysis of the nationally representative 2004 National Nursing Home Survey. The final sample of 1,174 participating nursing homes were either certified by Medicare or Medicaid or licensed by state agencies. We used a weighted multinomial logistic regression using an incremental approach to model the relationships. Although most nursing homes offered some combination of retention programs, the majority of strategies did not have a significant association with the level of RN retention reported by facilities. Director of nursing tenure and other extrinsic factors had the strongest association with RN retention in adjusted analyses. To improve RN retention, organizations may benefit greatly from stabilizing nursing home leadership, especially the director of nursing position. Second, managers of facilities with poor retention may consider adding career ladders for advancement, awarding attendance, and improving employee benefits. As a behavioral outcome of motivation and satisfaction, retention was not explained as expected using Herzberg's two-factor theory.

The Subjectivity of Participation

DEFF Research Database (Denmark)

Nissen, Morten

of a community of social/youth workers in Copenhagen between 1987 and 2003, who developed a pedagogy through creating collectives and mobilizing young people as participants. The theoretical and practical traditions are combined in a unique methodology viewing research as a contentious modeling of prototypical......What is a 'we' – a collective – and how can we use such communal self-knowledge to help people? This book is about collectivity, participation, and subjectivity – and about the social theories that may help us understand these matters. It also seeks to learn from the innovative practices and ideas...

Rapidly disintegrating vagina retentive cream suppositories of progesterone: development, patient satisfaction and in vitro/in vivo studies.

Science.gov (United States)

Bendas, Ehab Rasmy; Basalious, Emad B

2016-01-01

Our objective was to develop novel vagina retentive cream suppositories (VRCS) of progesterone having rapid disintegration and good vaginal retention. VRCS of progesterone were prepared using oil in water (o/w) emulsion of mineral oil or theobroma oil in hard fat and compared with conventional vaginal suppositories (CVS) prepared by hard fat. VRCS formulations were tested for content uniformity, disintegration, melting range, in vitro release and stability studies. The most stable formulation (VRCS I) was subjected to scaling-up manufacturing and patients' satisfaction test. The rapid disintegration, good retentive properties are applicable through the inclusion of emulsified theobroma oil rather than hydrophilic surfactant into the hard fat bases. The release profile of progesterone from VRCS I showed a biphasic pattern due to the formation of progesterone reservoir in the emulsified theobroma oil. All volunteers involved in patients' satisfaction test showed high satisfactory response to the tested formulation (VRCS). The in vivo pharmacokinetic study suggests that VRCS of progesterone provided higher rate and extent of absorption compared to hard fat based suppositories. Our results proposed that emulsified theobroma oil could be promising to solve the problems of poor patients' satisfaction and variability of drug absorption associated with hard fat suppositories.

Modified dark matter: Relating dark energy, dark matter and baryonic matter

Science.gov (United States)

Edmonds, Douglas; Farrah, Duncan; Minic, Djordje; Ng, Y. Jack; Takeuchi, Tatsu

Modified dark matter (MDM) is a phenomenological model of dark matter, inspired by gravitational thermodynamics. For an accelerating universe with positive cosmological constant (Λ), such phenomenological considerations lead to the emergence of a critical acceleration parameter related to Λ. Such a critical acceleration is an effective phenomenological manifestation of MDM, and it is found in correlations between dark matter and baryonic matter in galaxy rotation curves. The resulting MDM mass profiles, which are sensitive to Λ, are consistent with observational data at both the galactic and cluster scales. In particular, the same critical acceleration appears both in the galactic and cluster data fits based on MDM. Furthermore, using some robust qualitative arguments, MDM appears to work well on cosmological scales, even though quantitative studies are still lacking. Finally, we comment on certain nonlocal aspects of the quanta of modified dark matter, which may lead to novel nonparticle phenomenology and which may explain why, so far, dark matter detection experiments have failed to detect dark matter particles.

[A voxel-based morphometric analysis of brain gray matter in online game addicts].

Science.gov (United States)

Weng, Chuan-bo; Qian, Ruo-bing; Fu, Xian-ming; Lin, Bin; Ji, Xue-bing; Niu, Chao-shi; Wang, Ye-han

2012-12-04

To explore the possible brain mechanism of online game addiction (OGA) in terms of brain morphology through voxel-based morphometric (VBM) analysis. Seventeen subjects with OGA and 17 age- and gender-matched healthy controls (HC group) were recruited from Department of Psychology at our hospital during February-December 2011. The internet addiction scale (IAS) was used to measure the degree of OGA tendency. Magnetic resonance imaging (MRI) scans were performed to acquire 3-dimensional T1-weighted images. And FSL 4.1 software was employed to confirm regional gray matter volume changes. For the regions where OGA subjects showed significantly different gray matter volumes from the controls, the gray matter volumes of these areas were extracted, averaged and regressed against the scores of IAS. The OGA group had lower gray matter volume in left orbitofrontal cortex (OFC), left medial prefrontal cortex (mPFC), bilateral insula (INS), left posterior cingulate cortex (PCC) and left supplementary motor area (SMA). Gray matter volumes of left OFC and bilateral INS showed a negative correlation with the scores of IAS (r = -0.65, r = -0.78, P online game addicts and they may be correlated with the occurrence and maintenance of OGA.

Influence of Soil Management on Water Retention from Saturation to Oven Dryness and Dominant Soil Water States in a Vertisol under Crop Rotation

Science.gov (United States)

Vanderlinden, Karl; Pachepsky, Yakov; Pederera, Aura; Martinez, Gonzalo; Espejo, Antonio Jesus; Giraldez, Juan Vicente

2014-05-01

Unique water transfer and retention properties of Vertisols strongly affect their use in rainfed agriculture in water-limited environments. Despite the agricultural importance of the hydraulic properties of those soils, water retention data dryer than the wilting point are generally scarce, mainly as a result of practical constraints of traditional water retention measurement methods. In this work we provide a detailed description of regionalized water retention data from saturation to oven dryness, obtained from 54 minimally disturbed topsoil (0-0.05m) samples collected at a 3.5-ha experimental field in SW Spain where conventional tillage (CT) and direct drilling (DD) is compared in a wheat-sunflower-legume crop rotation on a Vertisol. Water retention was measured from saturation to oven dryness using sand and sand-kaolin boxes, a pressure plate apparatus and a dew point psychrometer, respectively. A common shape of the water retention curve (WRC) was observed in both tillage systems, with a strong discontinuity in its slope near -0.4 MPa and a decreasing spread from the wet to the dry end. A continuous function, consisting of the sum of a double exponential model (Dexter et al, 2008) and the Groenevelt and Grant (2004) model could be fitted successfully to the data. Two inflection points in the WRC were interpreted as boundaries between the structural and the textural pore spaces and between the textural and the intra-clay aggregate pore spaces. Water retention was significantly higher in DD (ptillage and compaction, increasing and decreasing the amount of the largest pores in CT and DD, respectively, but resulting in a proportionally larger pore space with relevant pore-sizes for water dynamics and agronomic performance. Significant differences in water retention and equivalent pore-sizes at the dry end of the WRC could be associated with the higher organic matter content found in DD. These results explain the superior performance of DD over CT in satisfying

Thermal effect on water retention curve of bentonite: experiment and thermodynamic modeling

International Nuclear Information System (INIS)

Qin Bing; Chen Zhenghai; Sun Faxin; Liu Yuemiao; Wang Ju

2012-01-01

The thermal effects on water retention curve of GMZ bentonite were investigated experimentally and theoretically. Water retention tests were conducted on GMZ bentonite at five temperatures ranging from 20℃ to 100℃. Test results showed that the water retention capacity and the hysteresis of the water retention curve decreased with increasing temperature, and that the water retention curves at different temperatures were almost parallel to each other. Based on the thermodynamics of sorption, a model was established to describe the temperature influence on the water retention curve. The model was validated by comparing the model predictions and the test results. (authors)

Retention of Esperanto Is Affected by Delay-Interval Task and Item Closure: A Partial Resolution of the Delay-Retention Effect

Science.gov (United States)

Brosvic, Gary M.; Epstein, Michael L.; Dihoff, Roberta E.; Cook, Michael L.

2006-01-01

The present studies were undertaken to examine the effects of manipulating delay-interval task (Study 1) and timing of feedback (Study 2) on acquisition and retention. Participants completed a 100-item cumulative final examination, which included 50 items from each laboratory examination, plus 50 entirely new items. Acquisition and retention were…

Impact of distributed virtual reality on engineering knowledge retention and student engagement

Science.gov (United States)

Sulbaran, Tulio Alberto

Engineering Education is facing many problems, one of which is poor knowledge retention among engineering students. This problem affects the Architecture, Engineering, and Construction (A/E/C) industry, because students are unprepared for many necessary job skills. This problem of poor knowledge retention is caused by many factors, one of which is the mismatch between student learning preferences and the media used to teach engineering. The purpose of this research is to assess the impact of Distributed Virtual Reality (DVR) as an engineering teaching tool. The implementation of DVR addresses the issue of poor knowledge retention by impacting the mismatch between learning and teaching style in the visual versus verbal spectrum. Using as a point of departure three knowledge domain areas (Learning and Instruction, Distributed Virtual Reality and Crane Selection as Part of Crane Lift Planning), a DVR engineering teaching tool is developed, deployed and assessed in engineering classrooms. The statistical analysis of the data indicates that: (1) most engineering students are visual learners; (2) most students would like more classes using DVR; (3) engineering students find DVR more engaging than traditional learning methods; (4) most students find the responsiveness of the DVR environments to be either good or very good; (5) all students are able to interact with DVR and most of the students found it easy or very easy to navigate (without previous formal training in how to use DVR); (6) students' knowledge regarding the subject (crane selection) is higher after the experiment; and, (7) students' using different instructional media do not demonstrate statistical difference in knowledge retained after the experiment. This inter-disciplinary research offers opportunities for direct and immediate application in education, research, and industry, due to the fact that the instructional module developed (on crane selection as part of construction crane lift planning) can be

White Matter Hyperintensities on MRI in High-Altitude U-2 Pilots

Science.gov (United States)

2013-08-19

SUBJECT TERMS MRI; white matter hyperintensities; hypobaric exposure; neurological decompression sickness 16. SECURITY CLASSIFICATION OF: 17...normal controls and did not increase with age in pilots, suggesting that hypobaric exposure produces white matter damage different from that occurring in...relapse we observed in 3 NDCS pilots after successful hyperbaric treatment (US Navy Treatment Table 6; 100% fraction of inspired oxygen; 2.8 atm absolute

44 CFR 321.5 - Retention of industrial facilities.

Science.gov (United States)

2010-10-01

... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Retention of industrial facilities. 321.5 Section 321.5 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY..., DEPARTMENT OF ENERGY, MARITIME ADMINISTRATION) § 321.5 Retention of industrial facilities. (a) Industrial...

Effects of fire ash on soil water retention

NARCIS (Netherlands)

Stoof, C.R.; Wesseling, J.G.; Ritsema, C.J.

2010-01-01

Despite the pronounced effect of fire on soil hydrological systems, information on the direct effect of fire on soil water retention characteristics is limited and contradictory. To increase understanding in this area, the effect of fire on soil water retention was evaluated using laboratory burning

40 CFR 94.406 - Reports filing: record retention.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Reports filing: record retention. 94.406 Section 94.406 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... Requirements, Voluntary Emission Recall Program § 94.406 Reports filing: record retention. (a) The reports...

21 CFR 320.38 - Retention of bioavailability samples.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Retention of bioavailability samples. 320.38... (CONTINUED) DRUGS FOR HUMAN USE BIOAVAILABILITY AND BIOEQUIVALENCE REQUIREMENTS Procedures for Determining the Bioavailability or Bioequivalence of Drug Products § 320.38 Retention of bioavailability samples...

5 CFR 2411.14 - Record retention and preservation.

Science.gov (United States)

2010-01-01

... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Record retention and preservation. 2411.14 Section 2411.14 Administrative Personnel FEDERAL LABOR RELATIONS AUTHORITY, GENERAL COUNSEL OF THE... OFFICIAL INFORMATION § 2411.14 Record retention and preservation. The Authority, the General Counsel, the...

48 CFR 2152.215-70 - Contractor records retention.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Contractor records... PRECONTRACT PROVISIONS AND CONTRACT CLAUSES Text of Provisions and Clauses 2152.215-70 Contractor records retention. As prescribed in 2115.071, insert the following clause: Contractor Records Retention (OCT 2005...

48 CFR 1652.204-70 - Contractor records retention.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Contractor records... of FEHBP Clauses 1652.204-70 Contractor records retention. As prescribed in 1604.705 the following clause will be inserted in all FEHB Program contracts. Contractor Records Retention (JUL 2005...

The Subject's Matter

DEFF Research Database (Denmark)

The body may be the object we know the best. It is the only object from which we constantly receive a flow of information through sight and touch; and it is the only object we can experience from the inside, through our proprioceptive, vestibular, and visceral senses. Yet there have been very few...

Psychological determinants of job retention in multiple sclerosis.

Science.gov (United States)

Ford, Helen L; Wicks, Charlotte R; Stroud, Amanda; Tennant, Alan

2018-01-01

Maintaining paid work is a key issue for people with multiple sclerosis (PwMS). Different factors, including psychological attributes, can influence job retention. Understanding their role should inform potential interventions to help PwMS retain employment. The aim of this study was to identify the key factors which improve job retention in an employed cohort of PwMS. This three-year longitudinal study used validated self-completed measures of physical and psychological factors at four time points over 28 months. Of 208 employed PwMS, just over 1 in 10 was no longer working at the end of the study. Three variables were predictive of continuing employment; low 'work instability' at baseline increased the odds of job retention by a factor of 12.76; high levels of self-efficacy by a factor of 4.66 and being less than 50 years of age increased the odds of job retention by a factor of 3.90. Path analysis demonstrated the mediating role of self-efficacy between the physical impact of MS and the level of work instability at exit. Screening for work instability and self-efficacy in a clinical setting followed by appropriate interventions to increase self-efficacy and reduce work instability could aid job retention in MS.

Automatic generation of matter-of-opinion video documentaries

NARCIS (Netherlands)

Bocconi, S.; Nack, F.; Hardman, H.L.

2008-01-01

In this paper we describe a model for automatically generating video documentaries. This allows viewers to specify the subject and the point of view of the documentary to be generated. The domain is matter-of-opinion documentaries based on interviews. The model combines rhetorical presentation

Automatic generation of matter-of-opinion video documentaries

NARCIS (Netherlands)

S. Bocconi; F.-M. Nack (Frank); L. Hardman (Lynda)

2008-01-01

textabstractIn this paper we describe a model for automatically generating video documentaries. This allows viewers to specify the subject and the point of view of the documentary to be generated. The domain is matter-of-opinion documentaries based on interviews. The model combines rhetorical

OCCIPITAL SOURCES OF RESTING STATE ALPHA RHYTHMS ARE RELATED TO LOCAL GRAY MATTER DENSITY IN SUBJECTS WITH AMNESIC MILD COGNITIVE IMPAIRMENT AND ALZHEIMER’S DISEASE

Science.gov (United States)

Claudio, Babiloni; Claudio, Del Percio; Marina, Boccardi; Roberta, Lizio; Susanna, Lopez; Filippo, Carducci; Nicola, Marzano; Andrea, Soricelli; Raffaele, Ferri; Ivano, Triggiani Antonio; Annapaola, Prestia; Serenella, Salinari; Rasser Paul, E; Erol, Basar; Francesco, Famà; Flavio, Nobili; Görsev, Yener; Durusu, Emek-Savaş Derya; Gesualdo, Loreto; Ciro, Mundi; Thompson Paul, M; Rossini Paolo, M.; Frisoni Giovanni, B

2014-01-01

Occipital sources of resting state electroencephalographic (EEG) alpha rhythms are abnormal, at the group level, in patients with amnesic mild cognitive impairment (MCI) and Alzheimer’s disease (AD). Here we evaluated the hypothesis that amplitude of these occipital sources is related to neurodegeneration in occipital lobe as measured by magnetic resonance imaging (MRI). Resting-state eyes-closed EEG rhythms were recorded in 45 healthy elderly (Nold), 100 MCI, and 90 AD subjects. Neurodegeneration of occipital lobe was indexed by weighted averages of gray matter density (GMD), estimated from structural MRIs. EEG rhythms of interest were alpha 1 (8–10.5 Hz) and alpha 2 (10.5–13 Hz). EEG cortical sources were estimated by low resolution brain electromagnetic tomography (LORETA). Results showed a positive correlation between occipital GMD and amplitude of occipital alpha 1 sources in Nold, MCI and AD subjects as a whole group (r=0.3, p=0.000004, N=235). Furthermore, there was a positive correlation between amplitude of occipital alpha 1 sources and cognitive status as revealed by Mini Mental State Evaluation (MMSE) score across all subjects (r=0.38, p=0.000001, N=235). Finally, amplitude of occipital alpha 1 sources allowed a moderate classification of individual Nold and AD subjects (sensitivity: 87.8%; specificity: 66.7%; area under the Receiver Operating Characteristic (ROC) curve: 0.81). These results suggest that the amplitude of occipital sources of resting state alpha rhythms is related to AD neurodegeneration in occipital lobe along pathological aging. PMID:25442118

Acute Retention of Urine Following Intraocular Surgery | Nwosu ...

African Journals Online (AJOL)

Hyperosmolar agents and carbonic anhydrase inhibitors are used to lower the intraocular pressure and thus minimize the chances of vitreous loss during intraocular surgery. However, these agents could precipitate urinary retention. This is a report on two elderly men who had perioperative acute urinary retention following ...

In vivo characterization of cortical and white matter neuroaxonal pathology in early multiple sclerosis.

Science.gov (United States)

Granberg, Tobias; Fan, Qiuyun; Treaba, Constantina Andrada; Ouellette, Russell; Herranz, Elena; Mangeat, Gabriel; Louapre, Céline; Cohen-Adad, Julien; Klawiter, Eric C; Sloane, Jacob A; Mainero, Caterina

2017-11-01

Neuroaxonal pathology is a main determinant of disease progression in multiple sclerosis; however, its underlying pathophysiological mechanisms, including its link to inflammatory demyelination and temporal occurrence in the disease course are still unknown. We used ultra-high field (7 T), ultra-high gradient strength diffusion and T1/T2-weighted myelin-sensitive magnetic resonance imaging to characterize microstructural changes in myelin and neuroaxonal integrity in the cortex and white matter in early stage multiple sclerosis, their distribution in lesional and normal-appearing tissue, and their correlations with neurological disability. Twenty-six early stage multiple sclerosis subjects (disease duration ≤5 years) and 24 age-matched healthy controls underwent 7 T T2*-weighted imaging for cortical lesion segmentation and 3 T T1/T2-weighted myelin-sensitive imaging and neurite orientation dispersion and density imaging for assessing microstructural myelin, axonal and dendrite integrity in lesional and normal-appearing tissue of the cortex and the white matter. Conventional mean diffusivity and fractional anisotropy metrics were also assessed for comparison. Cortical lesions were identified in 92% of early multiple sclerosis subjects and they were characterized by lower intracellular volume fraction (P = 0.015 by paired t-test), lower myelin-sensitive contrast (P = 0.030 by related-samples Wilcoxon signed-rank test) and higher mean diffusivity (P = 0.022 by related-samples Wilcoxon signed-rank test) relative to the contralateral normal-appearing cortex. Similar findings were observed in white matter lesions relative to normal-appearing white matter (all P test) and lower fractional anisotropy (P Wilcoxon signed-rank test) suggestive of less coherent underlying fibre orientation. Additionally, the normal-appearing white matter in multiple sclerosis subjects had diffusely lower intracellular volume fractions than the white matter in controls (P = 0.029 by unpaired

Planetary Exploration Education: As Seen From the Point of View of Subject Matter Experts

Science.gov (United States)

Milazzo, M. P.; Anderson, R. B.; Gaither, T. A.; Vaughan, R. G.

2016-12-01

Planetary Learning that Advances the Nexus of Engineering, Technology, and Science (PLANETS) was selected as one of 27 new projects to support the NASA Science Mission Directorate's Science Education Cooperative Agreement Notice. Our goal is to develop and disseminate out-of-school time (OST) curricular and related educator professional development modules that integrate planetary science, technology, and engineering. We are a partnership between planetary science Subject Matter Experts (SMEs), curriculum developers, science and engineering teacher professional development experts and OST teacher networks. The PLANETS team includes the Center for Science Teaching and Learning (CSTL) at Northern Arizona University (NAU); the U.S. Geological Survey (USGS) Astrogeology Science Center (Astrogeology), and the Boston Museum of Science (MOS). Here, we present the work and approach by the SMEs at Astrogeology. As part of this overarching project, we will create a model for improved integration of SMEs, curriculum developers, professional development experts, and educators. For the 2016 and 2017 Fiscal Years, our focus is on creating science material for two OST modules designed for middle school students. We will begin development of a third module for elementary school students in the latter part of FY2017. The first module focuses on water conservation and treatment as applied on Earth, the International Space Station, and at a fictional Mars base. This unit involves the science and engineering of finding accessible water, evaluating it for quality, treating it for impurities (i.e., dissolved and suspended), initial use, a cycle of greywater treatment and re-use, and final treatment of blackwater. The second module involves the science and engineering of remote sensing as it is related to Earth and planetary exploration. This includes discussion and activities related to the electromagnetic spectrum, spectroscopy and various remote sensing systems and techniques. In

Emotional intelligence, performance, and retention in clinical staff nurses.

Science.gov (United States)

Codier, Estelle; Kamikawa, Cindy; Kooker, Barbara M; Shoultz, Jan

2009-01-01

Emotional intelligence has been correlated with performance, retention, and organizational commitment in professions other than nursing. A 2006 pilot study provided the first evidence of a correlation between emotional intelligence and performance in clinical staff nurses. A follow-up study was completed, the purpose of which was to explore emotional intelligence, performance level, organizational commitment, and retention. A convenience sample of 350 nurses in a large medical center in urban Hawaii participated in this study. This article reports the findings pertaining to the subset of 193 clinical staff nurses who responded. The Mayer-Salovey-Caruso Emotional Intelligence Test instrument was used to measure emotional intelligence abilities. Performance was defined as ranking on a clinical ladder. Commitment was scored on a Likert scale. The following variables measured retention: total years in nursing, years in current job, total years anticipated in current job, and total anticipated career length. Emotional intelligence scores in clinical staff nurses correlated positively with both performance level and retention variables. Clinical staff nurses with higher emotional intelligence scores demonstrated higher performance, had longer careers, and greater job retention.

Rhetorical meta-language to promote the development of students' writing skills and subject matter understanding

Science.gov (United States)

Pelger, Susanne; Sigrell, Anders

2016-01-01

students' understanding of their subject matter.

Association between exercise habits and subcortical gray matter volumes in healthy elderly people: A population-based study in Japan.

Science.gov (United States)

Yamamoto, Mikie; Wada-Isoe, Kenji; Yamashita, Fumio; Nakashita, Satoko; Kishi, Masafumi; Tanaka, Kenichiro; Yamawaki, Mika; Nakashima, Kenji

2017-06-01

The relationship between exercise and subcortical gray matter volume is not well understood in the elderly population, although reports indicate that exercise may prevent cortical gray matter atrophy. To elucidate this association in the elderly, we measured subcortical gray matter volume and correlated this with volumes to exercise habits in a community-based cohort study in Japan. Subjects without mild cognitive impairment or dementia (n = 280, 35% male, mean age 73.1 ± 5.9 years) were evaluated using the Mini-Mental State Examination (MMSE), an exercise habit questionnaire, and brain magnetic resonance imaging. Subcortical gray matter volume was compared between groups based on the presence/absence of exercise habits. The MMSE was re-administered 3 years after the baseline examination. Ninety-one subjects (32.5%) reported exercise habits (exercise group), and 189 subjects (67.5%) reported no exercise habits (non-exercise group). Volumetric analysis revealed that the volumes in the exercise group were greater in the left hippocampus (p = 0.042) and bilateral nucleus accumbens (left, p = 0.047; right, p = 0.007) compared to those of the non-exercise group. Among the 195 subjects who received a follow-up MMSE examination, the normalized intra-cranial volumes of the left nucleus accumbens (p = 0.004) and right amygdala (p = 0.014)showed significant association with a decline in the follow-up MMSE score. Subjects with exercise habits show larger subcortical gray matter volumes than subjects without exercise habits in community-dwelling elderly subjects in Japan. Specifically, the volume of the nucleus accumbens correlates with both exercise habits and cognitive preservation.

Whole-brain voxel-based morphometry of white matter in mild cognitive impairment

International Nuclear Information System (INIS)

Wang Zhiqun; Guo Xiaojuan; Qi Zhigang; Yao Li; Li Kuncheng

2010-01-01

Purpose: The purpose of this study was to analyze whole-brain white matter changes in mild cognitive impairment (MCI). Materials and methods: We studied 14 patients with MCI and 14 age- and sex-matched healthy control subjects using voxel-based morphometry (VBM) on T1-weighted 3D datasets. The data were collected on a 3T MR system and analyzed by SPM2 to generate white matter volume maps. Results: Voxel-based morphometry revealed diffusively reduced white matter in MCI prominently including the bilateral temporal gyrus, the right anterior cingulate, the bilateral superior and medial frontal gyrus and right parietal angular gyrus. White matter reduction was more prominent in anterior regions than that in posterior regions. Conclusion: Whole-brain white matter reduction in MCI patients detected with VBM has special distribution which is in line with the white matter pathology of MCI.

Whole-brain voxel-based morphometry of white matter in mild cognitive impairment

Energy Technology Data Exchange (ETDEWEB)

Wang Zhiqun [Department of Radiology, Xuanwu Hospital of Capital Medical University, 100053, Beijing (China); Guo Xiaojuan [College of Information Science and Technology, Beijing Normal University, 100875, Beijing (China); National Key Laboratory for Cognitive Neuroscience and Learning, Beijing Normal University, 100875, Beijing (China); Qi Zhigang [Department of Radiology, Xuanwu Hospital of Capital Medical University, 100053, Beijing (China); Yao Li [College of Information Science and Technology, Beijing Normal University, 100875, Beijing (China); National Key Laboratory for Cognitive Neuroscience and Learning, Beijing Normal University, 100875, Beijing (China); Li Kuncheng, E-mail: likuncheng@xwh.ccmu.edu.c [Department of Radiology, Xuanwu Hospital of Capital Medical University, 100053, Beijing (China)

2010-08-15

Purpose: The purpose of this study was to analyze whole-brain white matter changes in mild cognitive impairment (MCI). Materials and methods: We studied 14 patients with MCI and 14 age- and sex-matched healthy control subjects using voxel-based morphometry (VBM) on T1-weighted 3D datasets. The data were collected on a 3T MR system and analyzed by SPM2 to generate white matter volume maps. Results: Voxel-based morphometry revealed diffusively reduced white matter in MCI prominently including the bilateral temporal gyrus, the right anterior cingulate, the bilateral superior and medial frontal gyrus and right parietal angular gyrus. White matter reduction was more prominent in anterior regions than that in posterior regions. Conclusion: Whole-brain white matter reduction in MCI patients detected with VBM has special distribution which is in line with the white matter pathology of MCI.

Academic staff recruitment and retention challenges at the University ...

African Journals Online (AJOL)

Academic staff recruitment and retention challenges at the University of Botswana medical school. ... To document the medical school's staff recruitment and retention trends and challenges, and to propose ... AJOL African Journals Online.

Analysis of change of retention capacity of a small water reservoir

Science.gov (United States)

Výleta, R.; Danáčová, M.; Valent, P.

2017-10-01

This study is focused on the analysis of the changes of retention capacity of a small water reservoir induced by intensive erosion and sedimentation processes. The water reservoir is situated near the village of Vrbovce in the Western part of Slovakia, and the analysis is carried out for a period 2008-2017. The data used to build a digital elevation model (DEM) of the reservoir’s bed came from a terrain measurement, utilizing an acoustic Doppler current profiler (ADCP) to measure the water depth in the reservoir. The DEM was used to quantify the soil loss from agricultural land situated within the basin of the reservoir. The ability of the water reservoir to transform a design flood with a return period of 100 years is evaluated for both design (2008) and current conditions (2017). The results show that the small water reservoir is a subject to siltation, with sediments comprised of fine soil particles transported from nearby agricultural land. The ability of the water reservoir to transform a 100-year flood has not changed significantly. The reduction of the reservoir’s retention capacity should be systematically and regularly monitored in order to adjust its operational manual and improve its efficiency.

Actual drawing of histological images improves knowledge retention.

Science.gov (United States)

Balemans, Monique C M; Kooloos, Jan G M; Donders, A Rogier T; Van der Zee, Catharina E E M

2016-01-01

Medical students have to process a large amount of information during the first years of their study, which has to be retained over long periods of nonuse. Therefore, it would be beneficial when knowledge is gained in a way that promotes long-term retention. Paper-and-pencil drawings for the uptake of form-function relationships of basic tissues has been a teaching tool for a long time, but now seems to be redundant with virtual microscopy on computer-screens and printers everywhere. Several studies claimed that, apart from learning from pictures, actual drawing of images significantly improved knowledge retention. However, these studies applied only immediate post-tests. We investigated the effects of actual drawing of histological images, using randomized cross-over design and different retention periods. The first part of the study concerned esophageal and tracheal epithelium, with 384 medical and biomedical sciences students randomly assigned to either the drawing or the nondrawing group. For the second part of the study, concerning heart muscle cells, students from the previous drawing group were now assigned to the nondrawing group and vice versa. One, four, and six weeks after the experimental intervention, the students were given a free recall test and a questionnaire or drawing exercise, to determine the amount of knowledge retention. The data from this study showed that knowledge retention was significantly improved in the drawing groups compared with the nondrawing groups, even after four or six weeks. This suggests that actual drawing of histological images can be used as a tool to improve long-term knowledge retention. © 2015 American Association of Anatomists.

Evaluation of {sup 131}I retention in several adsorbers

Energy Technology Data Exchange (ETDEWEB)

Catanoso, Marcela F.; Osso Junior, Joao Alberto, E-mail: marcela.forli@gmail.co, E-mail: jaosso@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Diretoria de Radiofarmacia

2011-07-01

Several iodine radioisotopes are used in nuclear medicine for treatment and diagnostic purposes. The radioisotope {sup 131}I is used both in diagnosis and therapy due to its physical characteristics of decay by {beta}{sup -} and its {gamma}-ray emissions suitable for diagnosis. It is routinely produced at IPEN through the irradiation of TeO{sub 2} targets in the IEA-R1m nuclear reactor. After the irradiation, the {sup 131}I is separated by dry distillation, where the targets are put in an oven, heated at 760 deg C for 2 hours and the {sup 131}I, volatile, is carried by an O{sub 2} gas stream. The aim of this work was to evaluate the retention and elution of {sup 131}I samples produced at IPEN in several adsorbers as part of a project aiming the purification of these radioisotopes, allowing the labeling of biomolecules. Samples of {sup 131}I were used for retention and elution studies with the following adsorbers: commercial cartridges, anionic resin columns and cationic resin column. The results showed that Ag cartridges and anionic resins Dowex 1X8, Dowex 3 and IRA 400 had a great iodine retention but no elution after using specific eluents. The QMA light, acid alumina, neutral alumina and cationic resin Dowex 50WX4 showed high retention and elution and QMA plus and cationic resin Dowex 50WX8 and Dowex 50WX12 had a good retention but lower elution. Regarding to the better retention and elution, Ag cartridges and resins showed a higher percentage of iodine retention but lower elution yield and QMA light, acid and neutral alumina cartridges showed better results. (author)

Grey matter changes of the pain matrix in patients with burning mouth syndrome.

Science.gov (United States)

Sinding, Charlotte; Gransjøen, Anne Mari; Schlumberger, Gina; Grushka, Miriam; Frasnelli, Johannes; Singh, Preet Bano

2016-04-01

Burning mouth syndrome (BMS) is characterized by a burning sensation in the mouth, usually in the absence of clinical and laboratory findings. Latest findings indicate that BMS could result from neuropathic trigeminal conditions. While many investigations have focused on the periphery, very few have examined possible central dysfunctions. To highlight changes of the central system of subjects with BMS, we analysed the grey matter concentration in 12 subjects using voxel-based morphometry. Data were compared with a control group (Ct). To better understand the brain mechanisms underlying BMS, the grey matter concentration of patients was also compared with those of dysgeusic patients (Dys). Dysgeusia is another oral dysfunction condition, characterized by a distorted sense of taste and accompanied by a reduced taste function. We found that a major part of the 'pain matrix' presented modifications of the grey matter concentration in subjects with BMS. Six regions out of eight were affected [anterior and posterior cingulate gyrus, lobules of the cerebellum, insula/frontal operculum, inferior temporal area, primary motor cortex, dorsolateral pre-frontal cortex (DLPFC)]. In the anterior cingulate gyrus, the lobules of the cerebellum, the inferior temporal lobe and the DLPFC, pain intensity correlated with grey matter concentration. Dys also presented changes in grey matter concentration but in different areas of the brain. Our results suggest that a deficiency in the control of pain could in part be a cause of BMS and that BMS and dysgeusia conditions are not linked to similar structural changes in the brain. © 2016 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Past and present of nuclear matter

International Nuclear Information System (INIS)

Ritter, H.G.

1994-05-01

The subject of nuclear matter is interesting for many fields of physics ranging from condensed matter to lattice QCD. Knowing its properties is important for our understanding of neutron stars, supernovae and cosmology. Experimentally, we have the most precise information on ground state nuclear matter from the mass formula and from the systematics of monopole vibrations. This gives us the ground state density, binding energy and the compression modulus k at ground state density. However, those methods can not be extended towards the regime we are most interested in, the regime of high density and high temperature. Additional information can be obtained from the observation of neutron stars and of supernova explosions. In both cases information is limited by the rare events that nature provides for us. High energy heavy ion collisions, on the other hand, allow us to perform controlled experiments in the laboratory. For a very short period in time we can create a system that lets us study nuclear matter properties. Density and temperature of the system depend on the mass of the colliding nuclei, on their energy and on the impact parameter. The system created in nuclear collisions has at best about 200 constituents not even close to infinite nuclear matter, and it lasts only for collision times of ∼ 10 -22 sec, not an ideal condition for establishing any kind of equilibrium. Extended size and thermal and chemical equilibrium, however, axe a priori conditions of nuclear matter. As a consequence we need realistic models that describe the collision dynamics and non-equilibrium effects in order to relate experimental observables to properties of nuclear matter. The study of high energy nuclear collisions started at the Bevalac. I will try to summarize the results from the Bevalac studies, the highlights of the continuing program, and extension to higher energies without claiming to be complete

High-pressure size exclusion chromatography analysis of dissolved organic matter isolated by tangential-flow ultra filtration

Science.gov (United States)

Everett, C.R.; Chin, Y.-P.; Aiken, G.R.

1999-01-01

A 1,000-Dalton tangential-flow ultrafiltration (TFUF) membrane was used to isolate dissolved organic matter (DOM) from several freshwater environments. The TFUF unit used in this study was able to completely retain a polystyrene sulfonate 1,800-Dalton standard. Unaltered and TFUF-fractionated DOM molecular weights were assayed by high-pressure size exclusion chromatography (HPSEC). The weight-averaged molecular weights of the retentates were larger than those of the raw water samples, whereas the filtrates were all significantly smaller and approximately the same size or smaller than the manufacturer-specified pore size of the membrane. Moreover, at 280 nm the molar absorptivity of the DOM retained by the ultrafilter is significantly larger than the material in the filtrate. This observation suggests that most of the chromophoric components are associated with the higher molecular weight fraction of the DOM pool. Multivalent metals in the aqueous matrix also affected the molecular weights of the DOM molecules. Typically, proton-exchanged DOM retentates were smaller than untreated samples. This TFUF system appears to be an effective means of isolating aquatic DOM by size, but the ultimate size of the retentates may be affected by the presence of metals and by configurational properties unique to the DOM phase.

Interacting dark matter disguised as warm dark matter

International Nuclear Information System (INIS)

Boehm, Celine; Riazuelo, Alain; Hansen, Steen H.; Schaeffer, Richard

2002-01-01

We explore some of the consequences of dark-matter-photon interactions on structure formation, focusing on the evolution of cosmological perturbations and performing both an analytical and a numerical study. We compute the cosmic microwave background anisotropies and matter power spectrum in this class of models. We find, as the main result, that when dark matter and photons are coupled, dark matter perturbations can experience a new damping regime in addition to the usual collisional Silk damping effect. Such dark matter particles (having quite large photon interactions) behave like cold dark matter or warm dark matter as far as the cosmic microwave background anisotropies or matter power spectrum are concerned, respectively. These dark-matter-photon interactions leave specific imprints at sufficiently small scales on both of these two spectra, which may allow us to put new constraints on the acceptable photon-dark-matter interactions. Under the conservative assumption that the abundance of 10 12 M · galaxies is correctly given by the cold dark matter, and without any knowledge of the abundance of smaller objects, we obtain the limit on the ratio of the dark-matter-photon cross section to the dark matter mass σ γ-DM /m DM -6 σ Th /(100 GeV)≅6x10 -33 cm 2 GeV -1

Manager impact on retention of hospital staff: Part 2.

Science.gov (United States)

Taunton, R L; Krampitz, S D; Woods, C Q

1989-04-01

This is the second article in a two-part series based on a study of the impact of middle managers on retention of 71 hospital professionals. Research design, methods, and descriptive results were presented in Part 1 (March 1989). In Part 2, the impact of managers' motivation to manage, power, influence, and leadership style on retention is detailed. Recommendations for improving retention include interventions to increase employee job satisfaction and intent to stay, and to improve managers' performance and leadership.

The importance of localisation within 131J-retention measurements

International Nuclear Information System (INIS)

Greifeneder, G.; Aiginger, H.; Steger, F.; Flores, J.

1996-01-01

A widely used method to investigate thyroid gland carcinomas, but also disorders of the thyroid gland is the measurement of the 131 J-retention behaviour using a high-sensitivity whole-body counter (HWBC). Normally just the retention of oral administered Radioiodine is controlled. However, it is possible to visualize the distribution of 131 J (using a modified profilescantechnique) beside the retention in the human body and this provides much better information on human metabolism as will be demonstrated in the following

Krypton retention on solid adsorbents

International Nuclear Information System (INIS)

Monson, P.R. Jr.

1982-01-01

An experimental laboratory program was conducted to develop economical solid adsorbents for the retention of krypton from a dissolver off-gas stream. The study indicates that a solid adsorbent system is feasible and competitive with other developing systems which utilize fluorocarbon absorption nd cryogenic distillation. This technology may have potential applications not only in nuclear fuel reprocessing plants, but also in nuclear reactors and in environmental monitoring. Of the 13 prospective adsorbents evaluated with respect to adsorption capacity and cost, the commercially available hydrogen mordenite was the most cost-effective material at subambient temperatures (-40 0 to -80 0 C). Silver mordenite has a higher capacity for krypton retention, but is 50 times more expensive than hydrogen mordenite

The role of glucocorticoids in sodium retention in cirrhotic patients

DEFF Research Database (Denmark)

Hansen, Martin Højmark; Kristensen, Steffen Skott; Schaffalitzky de Muckadell, Ove B

2012-01-01

sodium retention evident in cirrhosis. The aim was to elucidate the role of glucocorticoids in sodium retention in decompensated cirrhotic patients. Methods. A randomized, double-blind, placebo-controlled, crossover study was performed in nine patients with alcoholic cirrhosis of the liver. A washout....... Conclusion. These results indicate that endogenous glucocorticoids contribute to the sodium retention in patients with alcoholic cirrhosis of the liver....

Employee Engagement as a Predictor of Seafarer Retention: A Study among Indian Officers

Directory of Open Access Journals (Sweden)

Yogendra Bhattacharya

2015-06-01

Full Text Available This paper is part of a study of employee engagement and its relationship with seafarer safety, performance and retention. This section focuses on the impact of seafarer turnover, identifies and understands drivers of retention and their relevance in shipping, and explores the relationship of engagement with retention. It determines the correlation between retention and engagement and analyses drivers of retention from the seafarer's perspective. It also identifies aspects of shipboard life that can contribute towards higher retention. The study confirms that engagement was significantly and positively related with retention levels, while factor analysis isolated six contributory factors. The study also reveals that retention levels of officers employed directly by ship owners and by managers did not differ significantly, nor did they significantly differ between senior and junior officers.

RETENTION TIME EFFECT ON METAL REMOVAL BY PEAT COLUMNS

Energy Technology Data Exchange (ETDEWEB)

Nelson, E

2007-02-28

The potential use of a peat bed to treat the H-12 Outfall discharge to bring it to new compliance limits was previously investigated and reported utilizing a 7 hour retention time. The influence of retention time (contact time) of water with peat moss on the removal of copper from the water was investigated under laboratory conditions using vertical flow peat moss columns. Reduction of the necessary retention time has a large influence on the design sizing of any peat bed that would be constructed to treat the H-12 discharge on a full scale basis. Retention times of 5 hours, 3 hours and 1 hour were tested to determine the copper removal by the peat columns using vertical flow. Water samples were collected after 4, 8, 12, and 16 water volumes had passed through the columns and analyzed for a suite of metals, with quantitative emphasis on copper. Laboratory results indicated that copper removal was very high at each of the 3 retention times tested, ranging from 99.6 % removal at 5 and 3 hours to 98.8% removal at 1 hour. All these values are much lower that the new compliance limit for the outfall. The results also indicated that most divalent metals were removed to their normal reporting detection limit for the analytical methods used, including zinc. Lead levels in the H-12 discharge used in this study were below PQL in all samples analyzed. While each of the retention times studied removed copper very well, there were indications that 1 hour is probably too short for an operational, long-term facility. At that retention time, there was about 6% compaction of the peat in the column due to the water velocity, and this may affect long term hydraulic conductivity of the peat bed. At that retention time, copper concentration in the effluent was higher than the other times tested, although still very low. Because of the potential compacting and somewhat reduced removal efficiency at a 1 hour retention time, it would be prudent to design to at least a 3 hour retention

Subclinical Disease Burden as Assessed by Whole-Body MRI in Subjects With Prediabetes, Subjects With Diabetes, and Normal Control Subjects From the General Population: The KORA-MRI Study.

Science.gov (United States)

Bamberg, Fabian; Hetterich, Holger; Rospleszcz, Susanne; Lorbeer, Roberto; Auweter, Sigrid D; Schlett, Christopher L; Schafnitzel, Anina; Bayerl, Christian; Schindler, Andreas; Saam, Tobias; Müller-Peltzer, Katharina; Sommer, Wieland; Zitzelsberger, Tanja; Machann, Jürgen; Ingrisch, Michael; Selder, Sonja; Rathmann, Wolfgang; Heier, Margit; Linkohr, Birgit; Meisinger, Christa; Weber, Christian; Ertl-Wagner, Birgit; Massberg, Steffen; Reiser, Maximilian F; Peters, Annette

2017-01-01

Detailed pathophysiological manifestations of early disease in the context of prediabetes are poorly understood. This study aimed to evaluate the extent of early signs of metabolic and cardio-cerebrovascular complications affecting multiple organs in individuals with prediabetes. Subjects without a history of stroke, coronary artery disease, or peripheral artery disease were enrolled in a case-control study nested within the Cooperative Health Research in the Region of Augsburg (KORA) FF4 cohort and underwent comprehensive MRI assessment to characterize cerebral parameters (white matter lesions, microbleeds), cardiovascular parameters (carotid plaque, left ventricular function, and myocardial late gadolinium enhancement [LGE]), and metabolic parameters (hepatic proton-density fat fraction [PDFF] and subcutaneous and visceral abdominal fat). Among 400 subjects who underwent MRI, 103 subjects had prediabetes and 54 had established diabetes. Subjects with prediabetes had an increased risk for carotid plaque and adverse functional cardiac parameters, including reduced early diastolic filling rates as well as a higher prevalence of LGE compared with healthy control subjects. In addition, people with prediabetes had significantly elevated levels of PDFF and total and visceral fat. Thus, subjects with prediabetes show early signs of subclinical disease that include vascular, cardiac, and metabolic changes, as measured by whole-body MRI after adjusting for cardiometabolic risk factors. © 2017 by the American Diabetes Association.

Proteinuric diseases with sodium retention: Is plasmin the link?

DEFF Research Database (Denmark)

Svenningsen, Per; Skøtt, Ole; Jensen, Boye L

2012-01-01

1. Sodium retention in disease states characterized by proteinuria, such as nephrotic syndrome, preeclampsia, and diabetic nephropathy, occurs through poorly understood mechanism(s). 2. In the nephrotic syndrome, data from experimental and clinical studies indicate that the sodium retention...... originates in the renal cortical collecting duct and involves hyper-activity of the epithelial sodium channel (ENaC). 3. The stimulus for the increased ENaC activity does not appear to involve any of the classical sodium retaining mechanisms, such as the renin-angiotensin-aldosterone system, arginine...... and diabetic nephropathy, which are also characterized by proteinuria and sodium retention. 7. In this review, we will examine the evidence for a role of urinary serine protease activity in the development of sodium and water retention in diseases characterised by proteinuria with a focus on the nephrotic...