bluuebunny/crossref_metadata_2025 huggingface dataset:
G Protein–Coupled Receptor Kinase 2, With β-Arrestin 2, Impairs Insulin-Induced Akt/Endothelial Nitric Oxide Synthase Signaling in ob/ob Mouse Aorta
Authors: Taguchi Kumiko , Matsumoto Takayuki , Kamata Katsuo , Kobayashi Tsuneo
Published: June 2012

In type 2 diabetes, impaired insulin-induced Akt/endothelial nitric oxide synthase (eNOS) signaling may decrease the vascular relaxation response. Previously, we reported that this response was negatively regulated by G protein–coupled receptor kinase 2 (GRK2). In this study, we investigated whether/how in aortas from ob/ob mice (a model of type 2 diabetes) GRK2 and β-arrestin 2 might regulate insulin-induced signaling. Endothelium-dependent relaxation was measured in aortic strips. GRK2, β-arrestin 2, and Akt/eNOS signaling pathway proteins and activities were mainly assayed by Western blotting. In ob/ob (vs. control [Lean]) aortas: 1) insulin-induced relaxation was reduced, and this deficit was prevented by GRK2 inhibitor, anti-GRK2 antibody, and an siRNA specifically targeting GRK2. The Lean aorta relaxation response was reduced to the ob/ob level by pretreatment with an siRNA targeting β-arrestin 2. 2) Insulin-stimulated Akt and eNOS phosphorylations were decreased. 3) GRK2 expression in membranes was elevated, and, upon insulin stimulation, this expression was further increased, but β-arrestin 2 was decreased. In ob/ob aortic membranes under insulin stimulation, the phosphorylations of Akt and eNOS were augmented by GRK2 inhibitor. In mouse aorta, GRK2 may be, upon translocation, a key negative regulator of insulin responsiveness and an important regulator of the β-arrestin 2/Akt/eNOS signaling, which is implicated in diabetic endothelial dysfunction.
Superprism effect in all-glass volumetric photonic crystals
Authors: Filipkowski A. , Buczyński R. , Waddie A. , Kujawa I. , Pysz D. , Taghizadeh M. , Stępień R.
Published: June 2012

This paper focuses on the superprism effect which can be obtained in low-contrast photonic crystals. The modelling is related to the newly developed method for all-dielectric photonic crystals. This places material constraints on the simulated crystals which limit the refractive index difference to 0.1 for all-glass photonic crystals and 0.6 for air-glass structures and forces us to focus on hexagonal lattices. The simulations show the existence of superprism effect in both types of structure for realistic glasses. In both cases various linear filling factors are studied in order to maximize the frequency range of the superprism effect. For the air-F2 glass structure it reaches 0.108 normalized frequencies and for the air-NC21 glass structure it reaches 0.99 normalized frequencies for TM polarization. For the double glass structures, the largest range is for the F2/NC21 photonic crystal and spans 0.012 normalized frequencies. In the F2/NC21 crystal the frequency range reaches 0.005 for TE polarization.
Evaluating the Solar Radiation System under the Climatic Condition of Dhaka, Bangladesh and Computing the Angstrom Coefficients
Authors: Rashid MA , Mamun RA , Sultana J , Hasnat A , Khan KA , Rahman M
Published: June 2012

In this research work some mathematical models have been simulated to estimate the regression coefficients, which are also known as Angstrom coefficients, with monthly and daily average solar radiation on horizontal surface using bright sunshine hours. This study of solar energy, information on solar radiation and its components at a given location is very essential for scientists, engineers, architects, agriculturists and hydrologists for various applications such as measuring aerosol optical thickness, solar heating, cooking, drying and interior illumination of buildings. But, for developing countries like Bangladesh, we have limitation of sophisticated measuring instruments. So, we have used some latitude based empirical models to calculate an important solar radiation geometry parameter- Angstrom Coefficients for Bangladesh without any help of costly instruments. DOI: http://dx.doi.org/10.3329/ijns.v2i1.10882 International Journal of Natural Sciences (2012), 2(1): 38-42
Investigation into Seasonal Effect and Browning Inhibitor on Callus Regeneration of Seedless Barberry (Berberis vulgaris var. asperma)
Authors: Mohammadi Morteza , Bagheri Abdolreza , Marashi Hasan , Moshtaghi Nasrin , Balandari Ahmad
Published: June 2012

Leaves, one year old stems and buds were used as explants. WPM, B5, MS, half and one-fourth strength MS with 2,4-?D, NAA, IBA, IAA and picloram 2, 5 and 10 mg/l were used for callus induction. Investigation into the seasonal effect on callus regeneration and explants browning was carried out in mid-April until September. Results showed that washing with sterile distilled water for one hour after surface sterilization was the best treatment for browning inhibition of explants than other treatments. Leaf explants have best callus formation. MS with 8 g/l agar had strong effect on callus formation. Culture for callus formation in May and June found to be higher than other months. 2,4-D, NAA and  10 mg/l picloram significantly enhanced callus formation. Leaf and bud explants sampling in April to May did not show any endophyte contamination but leaf explants in June until September, specially the one year old stems, showed intensive contamination.   Key words: Seasonal effect, Browning inhibitor, Berberis vulgaris   D. O. I. 10.3329/ptcb.v21i2.10239   Plant Tissue Cult. & Biotech. 21(2): 161-168, 2011 (December)
DNA Fingerprinting and Diversity Analysis of BRRI Hybrid Varieties and their Corresponding Parents
Authors: Islam M.M. , Hoque M.E. , Rabbi S.M.H.A. , Ali M.S.
Published: June 2012

DNA fingerprinting and genetic diversity of four Bangladesh Rice Research Institute (BRRI) hybrid varieties and their parental lines were carried out. A total of 73 microsatellite markers were tested for screening the genotypes. Among the 73 amplified products, 37% had polymorphic bands showing 81 alleles. The number of alleles per locus ranged from two (RM10) to eight (RM327), where average allele number was 4.333. The Polymorphism Information Contents (PIC) lied between 0.337 (RM10) and 0.852 (RM327). RM327 was the most robust marker providing the highest PIC value (0.852). Pair-wise genetic dissimilarity coefficient interaction showed that BRRI hybrids two was the most genetically distant from each other whereas BRRI hybrids one, three, four and their respective parents were very close. Cluster analysis based on Dices similarity coefficient UPGMA system grouped BRRI hybrid and their parental lines into four major clusters at 0.41 cut off similarity coefficient. Four BRRI hybrid varieties grouped into four distinct clusters along with their component lines indicating their genetic closeness. Key words: Hybrid rice, Diversity analysis, Microsatellite markers, DNA fingerprinting   D. O. I. 10.3329/ptcb.v21i2.10242   Plant Tissue Cult. & Biotech. 21(2): 189-198, 2011 (December)
Coordination Modes and Different Hapticities for Fullerene Organometallic Complexes
Authors: Soto Delia , Salcedo Roberto
Published: June 2012

The different coordination modes in fullerene organometallic complexes are reviewed. The main modes are η2 and η5, but there are some interesting studies about the other four, all of them are revised in order to show which is the state of art of this kind of compounds with the respect of the hapticity.
Synthesis and Biological Evaluation of Thiophene Derivatives as Acetylcholinesterase Inhibitors
Authors: Ismail Mohamed M. , Kamel Mona M. , Mohamed Lamia W. , Faggal Samar I. , Galal Mai A.
Published: June 2012

A series of new thiophene derivatives has been synthesized using the Gewald protocol. The acetylcholinesterase inhibition activity was assayed according to Ellman’s method using donepezil as reference. Some of the compounds were found to be more potent inhibitors than the reference. 2-(2-(4-(4-Methoxyphenyl)piperazin-1-yl)acetamido)-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxamide (IIId) showed 60% inhibition, compared to only 40% inhibition by donepezil.
Amino Acid and Peptide Immobilization on Oxidized Nanocellulose: Spectroscopic Characterization
Authors: Barazzouk Saïd , Daneault Claude
Published: June 2012

In this work, oxidized nanocellulose (ONC) was synthesized and chemically coupled with amino acids and peptides using a two step coupling method at room temperature. First, ONC was activated by N-ethyl-N’-(3-dimethylaminopropyl) carbodiimide hydrochloride, forming a stable active ester in the presence of N-hydroxysuccinimide. Second, the active ester was reacted with the amino group of the amino acid or peptide, forming an amide bond between ONC and the grafted molecule. Using this method, the intermolecular interaction of amino acids and peptides was avoided and uniform coupling of these molecules on ONC was achieved. The coupling reaction was very fast in mild conditions and without alteration of the polysaccharide. The coupling products (ONC-amino acids and ONC-peptides) were characterized by transmission electron microscopy and by the absorption, emission, Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) spectroscopic techniques.
Analyse du Discours à Entrée Lexicale (A.D.E.L.) : le renouveau par la sémantique ?
Authors: Née Émilie , Veniard Marie
Published: June 2012

Cet article fait le point sur les travaux en analyse du discours qui privilégient des entrées lexicales, en revenant au projet d’Analyse du Discours à Entrée Lexicale (A.D.E.L.) tel que l’a défini J.-B. Marcellesi (1976). En tutoyant l’histoire de l’analyse du discours (Mazière 2005, Paveau et Rosier 2005), nous retraçons le cheminement des études à entrée lexicale, depuis la lexicologie sociolinguistique jusqu’aux travaux intégrant l’interdiscours, avant de revenir sur ce qui fait la spécificité de l’A.D.E.L telle que nous l’entendons, c’est-à-dire l’articulation entre le lexique et l’énoncé, voie ouverte par J. Dubois (1969). En soulignant les limites des études de vocabulaire dans l’étude des textes et en introduisant l’énoncé contre le mot, ce dernier, en effet, a ouvert à l’analyse du discours une voie qui lui est propre, qui la distingue d’autres approches (histoire, sociologie ou, plus récemment, sciences de l’information et de la communication) et qui illustre un des postulats linguistiques de l’AD : l’articulation du sens à la syntaxe. Ainsi, en cherchant à relier le lexique aux autres dimensions de la discursivité, le principe paradoxal sur lequel s’appuie une recherche par les mots est que ces derniers sont amenés à être dépassés, de par leur solidarité avec la chaîne syntagmatique et avec le discours. C’est ce principe qui est à la base de l’ADEL et que nous cherchons à modéliser dans une perspective sémantique. Nous défendons l'idée que des avancées récentes en sémantique, telles qu'une approche praxéologique ou la sémantique des constructions, peuvent rendre compte de l'articulation du sens au discours, ce que nous illustrons à travers deux études de cas.
Une réception japonaise de Bergson : Miki Kiyoshi et l'empirisme intégral
Authors: Ebersolt Simon
Published: June 2012

Résumé La philosophie d’Henri Bergson fait l’objet d’une réception passionnée au Japon au début des années 1910, mais, étant donné un contexte spiritualiste critiquant la raison, elle est généralement interprétée comme un irrationalisme opposant l’intuition à l’intelligence. Le principal problème de la réception de 1941, à l’occasion de la mort de Bergson, est alors de montrer comment l’intuition en réalité collabore avec l’intelligence. Par l’examen de la notion d’« empirisme intégral », Miki Kiyoshi (1897-1945), qui a développé une philosophie dialectique influencée par Karl Marx et Martin Heidegger, tente d’y apporter une solution en rapprochant l’intuition bergsonienne de l’imagination kantienne.
Lettres inédites d'Henri Bergson à Salomon Reinach
Authors: Verdeau Patricia
Published: June 2012

Résumé Sont éditées et présentées 24 lettres de Bergson à Salomon Reinach. Outre l’intérêt biographique de cette correspondance, on y trouve trois lettres au moins offrant un véritable intérêt philosophique : une présentation par Bergson de la philosophie de William James et deux lettres sur des aspects de sa propre philosophie, suscitées par la préparation et la parution des Lettres à Zoé .
Cervical Pedicle Subtraction Osteotomy for Fixed Flexion Deformities
Authors: Khan Safdar N. , Braaksma Brian , An Howard S.
Published: June 2012

Flexion deformities of the cervical spine are multiplanar surgical challenges. This article describes a technical modification during the osteotomy that protects the cervical cord and exiting nerve roots while removing the maximal amount of bone for the osteotomy in the safest fashion.
Open Distal Femur Fractures Treated With Lateral Locked Implants: Union, Secondary Bone Grafting, and Predictive Parameters
Authors: Barei David P. , Beingessner Daphne M.
Published: June 2012

Nonunion and secondary reduction loss complicate open distal femur fractures with bone loss. The authors hypothesized that locking plates decrease subsequent bone grafting yet maintain alignment and immediate postfixation radiographic features predict primary union. A retrospective chart/radiographic review was performed at a Level 1 university trauma center. Thirty-four adults with 36 open AO/Orthopaedic Trauma Association (AO/OTA) C-type distal femur fractures were studied. All fractures were treated with open reduction, internal fixation with a lateral locked implant with or without antibiotic beads, and subsequent bone grafting. Union required radiographic bridging callus on at least 2 of 4 cortices. Alignment was assessed on initial and united radiographs. Antibiotic beads within a metaphyseal defect defined clinically important bone loss. Eleven (55%) of 20 fractures with bone loss underwent staged bone grafting to achieve union vs 2 (13%) of 16 fractures without bone loss. Antibiotic bead presence was associated with staged bone grafting (
P
<.01). Of those with bone loss and grafting, 3 had posterior cortical bone loss only, 3 had medial and posterior cortical bone loss, and 5 had segmental defects. Of 9 fractures with bone loss not requiring grafting, all had radiographic posterior cortical contact and 7 had radiographic medial cortical contact. Posterior cortical continuity was associated with injuries not requiring bone graft (
P
<.001). Thirty-four had accurate frontal plane reductions and 35 had accurate sagittal plane reductions. Despite metaphyseal bone loss, locking plates obviate the need for routine bone grafting of some open distal femur fractures. Those with radiographic posterior cortical contact are strongly correlated with primary union.
Retrograde Femoral Nailing in Elderly Patients: Outcome and Functional Results
Authors: Neubauer Thomas , Krawany Manfred , Leitner Lukas , Karlbauer Alois , Wagner Michael , Plecko Michael
Published: June 2012

Functional outcome after retrograde femoral intramedullary nailing was investigated in 35 patients older than 60 years (mean, 86 years) with 36 fractures, comprising 15 (41.7%) shaft and 21 (58.3%) distal fractures; overall, 7 (19.4%) periprosthetic fractures occured. Twenty-two (62.9%) of 35 patients were evaluated at a mean 16.5-month follow-up with the Lyshom-Gillquist score and the SF-8 questionaire. Primary union rate was 97.8%, with no significant differences in duration of surgery, bone healing, mobilization, and weight bearing among different fracture types; periprosthetic fractures revealed a significantly delayed mobilization (
P
=.03). Complications occured significantly more often among distal femoral fractures (
P
=.009), including all revision surgeries. The most frequently encountered complication was loosening of distal locking bolts (n=3). Lysholm score results were mainly influenced by age-related entities and revealed fair results in all fractures (mean in the femoral shaft fracture group, 78.1 vs mean in the distal femoral fracture group, 74.9;
P
=.69), except in the periprosthetic subgroup, which had good results (mean, 84.8;
P
=.23). This group also had increased physical parameters according to SF-8 score (
P
=.026). No correlation existed between SF-8 physical parameters and patient age or surgery delay, whereas a negative correlation existed between patient age and SF-8 mental parameters (
P
=.012). Retrograde femoral intramedullary nailing is commonly used in elderly patients due to reliable bone healing, minimal soft tissue damage, and immediate full weight bearing. It also offers a valid alternative to antegrade nailing in femoral shaft fractures.
External Fixation Versus ORIF for Distal Intra-articular Tibia Fractures
Authors: Richards Justin E. , Magill Mark , Tressler Marc A. , Shuler Franklin D. , Kregor Philip J. , Obremskey William T. ,   The Southeast Fracture Consortium
Published: June 2012

Tibia plafond fractures have historically demonstrated high complication rates. The purpose of this study was to assess the outcomes of tibia plafond fractures following treatment with definitive external fixation vs delayed open reduction and internal fixation (ORIF). Sixty patients were enrolled in a prospective cohort trial at 1 Level I trauma center. No differences were noted between the 2 treatment groups in terms of age, smoking history, presence of comorbidities, mechanism of injury, incidence of open fractures, or Orthopaedic Trauma Association fracture classification. Complete 12-month follow-up was available for 18 patients in the definitive external fixation group and 27 patients in the ORIF group. No difference was noted in articular reduction between the groups at 6 and 12 months postoperatively. Delayed union or non-union occurred in 4 (22.2%) of 18 patients in the external fixation group and 1 (3.7%) of 27 patients in the ORIF group (
P
=.05). Deep infection was equally likely in either group (
P
=.33). The ORIF group had improved Iowa Ankle Scores at 6 (23.6±12.1 vs 11.1±7.7;
P
<.05) and 12 months (5.5±2.2 vs 3.1±1.7;
P
<.05) postopertively and improved Short Form-36 Physical Function scores at 6 months (49.7±30.1 vs 25.5±18.0;
P
<.05) postoperatively compared with the external fixation group.

External fixation and ORIF can attain bony union with adequate articular reduction and similar infection rates. Patients treated with ORIF appeared to have improved union rates and early outcomes with ankle function and Short Form-36 Physical Function scores.
MRI Study of the Position of the Conus Medullaris in Patients With Lumbar Spinal Stenosis
Authors: Ba Zhaoyu , Zhao Weidong , Wu Desheng , Huang Yufeng , Kan Heng
Published: June 2012

Substantial data exist from cadaveric and magnetic resonance imaging studies regarding the position of the conus medullaris in normally developed adults. However, no large studies have documented the position of the conus medullaris in patients with diagnosed lumbar spinal stenosis. To goal of the current study was to determine the position of the conus medullaris within a living adult population with existing pathology of lumbar spinal stenosis. In a retrospective study, 234 patients (110 women and 124 men; mean age, 48.8 years) with diagnosed lumbar spinal stenosis had their T2-weighted, midline, sagittal, spin-echo magnetic resonance imaging studies compared to assess and confirm the position of the conus medullaris. A straight line perpendicular to the long axis of the spinal cord in the median sagittal sequence was subtended to the adjacent vertebra or disk space, and the position was defined in relation to the vertebra or disk space. The conus medullaris position was labeled in relation to the upper, middle, and lower segments of the adjacent vertebral body or the adjacent disk space and assigned numerical values from 1 to 12. The position of the conus medullaris in patients with lumbar spinal stenosis followed a normal distribution. The mean conus medullaris position was mainly within the lower third of the L1 vertebral body (ranged from the middle third of T12 to the upper third of L3). No significant differences existed between men and women with lumbar spinal stenosis. The conus medullaris position was found to be unaffected by the pathology of lumbar spinal stenosis.
Mirror-image Trigger Thumb in Dichorionic Identical Twins
Authors: Wang Eric D. , Xu Xiaoti , Dagum Alexander B.
Published: June 2012

The congenital vs acquired etiology of pediatric trigger thumb is the subject of considerable debate. Existing case reports of bilateral presentation in identical twins and first-degree familial association support the congenital hypothesis. However, prospective studies have yet to report a neonate presenting with this anomaly at birth. This article describes the first known set of dichorionic, monozygotic identical twins with unilateral trigger thumbs, affecting contralateral (mirror-image) hands and with asynchronous age at presentation (11 months and 18 months, respectively).

Pediatric trigger thumb is caused by a mismatch between the flexor pollicis longus tendon and its A1 synovial pulley. Four sets of twins have been previously reported in the literature with trigger thumb. Of these, 3 sets were monozygotic twins who had bilaterally affected thumbs. Together with the absence of trauma, a congenital etiology was suggested. The fact that pediatric trigger thumb is generally seen several months after birth was felt to be due to infants holding their thumbs clutched in their palms until 6 months. However, no confirmed cases of trigger thumb have been diagnosed at birth in several large prospective studies of newborns.

In the current case, the asynchronous presentation of unilateral trigger thumbs in identical twins does not support a solely congenital cause. Furthermore, the mirror-image presentation contradicts current embryological understanding of the temporal course of twinning and the determination of laterality. Thus, a multifactorial etiology is supported with both a genetic and acquired component affecting the development of this condition.
Psychiatric Nurses in the Age of Health Care Reform
Authors: Wilson Denise A.
Published: June 2012

With the March 2010 passage of the health care reform law, the Patient Protection and Affordable Care Act, the U.S. Congress completely transformed the health care industry and fundamentally altered how hospitals will deliver and receive payment for care. The purpose of this article is to examine the provisions of the Affordable Care Act and its significance for behavioral health care. Key components of health care reform (i.e., measuring and benchmarking quality patient care outcomes; payment reform; and the reorganization of the health care delivery system to ensure accountable, accessible, patient-centered, coordinated care) are reviewed with regard to their impact on behavioral health. The challenges, opportunities, and implications of health care reform are examined for the nursing field in general and for psychiatric nursing practice specifically.
Alterations of the Anterior Lens Capsule in Vitrectomized Eyes With Silicone Oil Tamponade
Authors: Citirik Mehmet , Sargon Mustafa F. , Has Semiha , Bilgin Selma
Published: June 2012

BACKGROUND AND OBJECTIVE:

To investigate the electron microscopic findings of the anterior lens capsule in vitrectomized eyes with silicone oil tamponade.

PATIENTS AND METHODS:

Ten eyes of 10 consecutive patients aged 39 to 74 years who had cataract surgery combined with silicone oil removal from December 2006 to May 2009 were included in the study. The control group included 10 patients with cataract extraction and intraocular lens implantation without history of systemic or other ocular disease. All anterior capsules underwent electron microscopic examination of the anterior lens capsule.

RESULTS:

During the capsulorhexis, the anterior lens capsule was removed. In the silicone oil tamponade group, silicone oil droplets were detected on the posterior surface of the anterior lens capsule in 5 cases (50%) and surface irregularities, pits, and depressions were present in the posterior surface of the anterior lens capsules in all cases.

CONCLUSION:

Silicone oil droplets may infiltrate the lens capsule, especially in diabetic patients. Surface irregularities may be associated with posterior fibrous pseudometaplasia produced by lens epithelial cells under the anterior lens capsule.
Geothermal energy resource potential of Canada
Authors: Grasby S E , Allen D M , Bell S , Chen Z , Ferguson G , Jessop A , Kelman M , Ko M , Majorowicz J , Moore M , Raymond J , Therrien R
Published: June 2012

Canada has enormous geothermal energy resources that could supply a renewable and clean source of power. There are many constraints, however, in utilizing this energy resource, including geological, technical, and regulatory issues. The intent of this report is
to examine the geothermal potential in Canada, and the geological controls on the distribution of high grade resources as well as controls on the economic development and production of geothermal energy. This assessment is based on a new compilation and digitization of data produced through over 48
years of geothermal research in Canada. Recommendations on current and future research needs to reduce barriers to resource production are made at the end of the report. Currently Canada has no geothermal electrical production; however, direct use and heat exchange systems are used widely. Several
projects are currently being examined by industry and government to develop electrical potential in Canada. A key economic constraint for these projects is the high risk of exploration due to costs of deep drilling. The cost of delivered geothermal power is projected to decline and be competitive
with coal fired production within the next 15 years, given current levels of technology. Canada's in-place geothermal power exceeds one million times Canada's current electrical consumption (Fig. 1). However, only a fraction of this total potential could be developed. Much of the resource lies
beyond current drilling technology, outside of areas served by high-capacity transmission lines, and at some distance from load centres. Nonetheless, the available high grade geothermal resource is considerable. High temperature hydrothermal systems can be brought on line with proven technology.
Many of the tools required to bring geothermal energy to full realization, however, are not commercially proven to date and require further research and technology development. We can expect a strong learning curve and price response as geothermal energy is developed while other energy sources such
as coal and nuclear will begin to see fleet and capacity retirements.
Diversity dynamics operating between students lecturers and management in a historically Black university: The lecturers perspective
Authors: May Michelle S.
Published: June 2012

Orientation: The historically Black and White universities in South Africa were shaped by apartheid policies (Abdi, 2003). This research project started, within this socio-political context, because lecturers in a historically Black university (HBU) were confronted with unresolved experiences concerning their relationship with students and management. The researcher describes the diversity dynamics in a historically Black university, by forming an in-depth understanding of these dynamics, operating in the relationship between the students, lecturers and management, from the systems psychodynamic perspective.Research purpose: The purpose of the research was to describe the experiences of nine lecturers in a particular HBU. This was undertaken to analyse and interpret the conscious and unconscious diversity dynamics operating in the relationship between the students, lecturers and management, from the lecturers’ perspective.Motivation for the study: The researcher was interested in the nature of the diversity dynamics operating in the relationship between students, lecturers and management in an HBU, as a platform towards understanding diversity dynamics in educational institutions and South African organisations.Research design, approach and method: Qualitative and descriptive research approaches were used. Hermeneutic phenomenology, using the systems psychodynamic perspective, allowed for the description and interpretation of diversity dynamics operating in the relationship between the students, lecturers and management. The data were obtained through in-depth interviews with nine lecturers. Thematic analysis resulted in two broad themes for which a discussion was provided and a research hypothesis formulated.Main findings: Two broad themes manifested, firstly diversity characteristics and secondly struggle skills entrenching the Black and White divide.Practical/managerial implications: The research highlighted the importance of understanding the diversity dynamics operating in the relationship between students, lecturers and management. This was in order to develop our understanding of diversity dynamics operating in educational institutions specifically, and organisations in general.Contribution/value-add: The understanding about diversity dynamics is available for application, by lecturers and management, to form a different understanding of conscious and unconscious factors impacting on the relationship between the three stakeholders, and subsequently the effectiveness of the three stakeholders in their respective roles. This understanding can also be transferred to other organisations.
Shortwave radiative forcing and efficiency of key aerosol types using AERONET data
Authors: García O. E. , Díaz J. P. , Expósito F. J. , Díaz A. M. , Dubovik O. , Derimian Y. , Dubuisson P. , Roger J.-C.
Published: June 2012

Abstract. The shortwave radiative forcing (ΔF) and the radiative forcing efficiency (ΔFeff) of natural and anthropogenic aerosols have been analyzed using estimates of radiation both at the Top (TOA) and at the Bottom Of Atmosphere (BOA) modeled based on AERONET aerosol retrievals. Six main types of atmospheric aerosols have been compared (desert mineral dust, biomass burning, urban-industrial, continental background, oceanic and free troposphere) in similar observational conditions (i.e., for solar zenith angles between 55° and 65°) in order to compare the nearly same solar geometry. The instantaneous ΔF averages obtained vary from −122 ± 37 Wm−2 (aerosol optical depth, AOD, at 0.55 μm, 0.85 ± 0.45) at the BOA for the mixture of desert mineral dust and biomass burning aerosols in West Africa and −42 ± 22 Wm−2 (AOD = 0.9 ± 0.5) at the TOA for the pure mineral dust also in this region up to −6 ± 3 Wm−2 and −4 ± 2 Wm−2 (AOD = 0.03 ± 0.02) at the BOA and the TOA, respectively, for free troposphere conditions. This last result may be taken as reference on a global scale. Furthermore, we observe that the more absorbing aerosols are overall more efficient at the BOA in contrast to at the TOA, where they backscatter less solar energy into the space. The analysis of the radiative balance at the TOA shows that, together with the amount of aerosols and their absorptive capacity, it is essential to consider the surface albedo of the region on which they are. Thus, we document that in regions with high surface reflectivity (deserts and snow conditions) atmospheric aerosols lead to a warming of the Earth-atmosphere system.
Sensitivity of cirrus and mixed-phase clouds to the ice nuclei spectra in McRAS-AC: single column model simulations
Authors: Morales Betancourt R. , Lee D. , Oreopoulos L. , Sud Y. C. , Barahona D. , Nenes A.
Published: June 2012

Abstract. The salient features of mixed-phase and ice clouds in a GCM cloud scheme are examined using the ice formation parameterizations of Liu and Penner (LP) and Barahona and Nenes (BN). The performance of LP and BN ice nucleation parameterizations were assessed in the GEOS-5 AGCM using the McRAS-AC cloud microphysics framework in single column mode. Four dimensional assimilated data from the intensive observation period of ARM TWP-ICE campaign was used to drive the fluxes and lateral forcing. Simulation experiments where established to test the impact of each parameterization in the resulting cloud fields. Three commonly used IN spectra were utilized in the BN parameterization to described the availability of IN for heterogeneous ice nucleation. The results show large similarities in the cirrus cloud regime between all the schemes tested, in which ice crystal concentrations were within a factor of 10 regardless of the parameterization used. In mixed-phase clouds there are some persistent differences in cloud particle number concentration and size, as well as in cloud fraction, ice water mixing ratio, and ice water path. Contact freezing in the simulated mixed-phase clouds contributed to transfer liquid to ice efficiently, so that on average, the clouds were fully glaciated at T~260 K, irrespective of the ice nucleation parameterization used. Comparison of simulated ice water path to available satellite derived observations were also performed, finding that all the schemes tested with the BN parameterization predicted average values of IWP within ±15% of the observations.
A 560 yr summer temperature reconstruction for the Western Mediterranean basin based on stable carbon isotopes from Pinus nigra ssp. laricio (Corsica/France)
Authors: Szymczak S. , Joachimski M. M. , Bräuning A. , Hetzer T. , Kuhlemann J.
Published: June 2012

Abstract. The Mediterranean is considered as an area which will be affected strongly by current climate change. However, temperature records for the past centuries which can contribute to a better understanding of future climate changes are still sparse for this region. We established a network of multi-century stable carbon isotope chronologies on Corsica to study long-term climate variation in the Western Mediterranean Basin. The chronologies show strong correlations with summer temperature and precipitation as well as summer cloud coverage. A summer temperature reconstruction (AD 1448–2008) reveals that the Little Ice Age was characterized by low, but not extremely low temperatures on Corsica. Relatively warm temperatures during the Maunder minimum may indicate a decoupling from climate cooling registered in northern latitudes. A comparison of the summer temperature reconstruction with a summer cloud coverage reconstruction indicates warm summers with reduced cloudiness during the periods AD 1480–1520 and 1950–2008 and cool and cloudy summers during AD 1580–1620 and 1820–1890. The distinct features of the reconstruction underline the uniqueness of the Corsican climate and highlight the necessity of a better temporal and spatial resolution of climate reconstructions for a more robust estimation of current climate change on a local scale.
Extended power-law scaling of heavy-tailed random fields or processes
Authors: Guadagnini A. , Riva M. , Neuman S. P.
Published: June 2012

Abstract. We analyze the scaling behaviors of two log permeability data sets showing heavy-tailed frequency distributions in three and two spatial dimensions, respectively. One set consists of 1-m scale pneumatic packer test data from six vertical and inclined boreholes spanning a decameters scale block of unsaturated fractured tuffs near Superior, Arizona, the other of pneumatic minipermeameter data measured at a spacing of 15 cm along two horizontal transects on a 21 m long outcrop of lower-shoreface bioturbated sandstone near Escalante, Utah. Order q sample structure functions of each data set scale as a power ξ (q) of separation scale or lag, s, over limited ranges of s. A procedure known as Extended Self-Similarity (ESS) extends this range to all lags and yields a nonlinear (concave) functional relationship between ξ (q) and q. Whereas the literature tends to associate extended and nonlinear power-law scaling with multifractals or fractional Laplace motions, we have shown elsewhere that (a) ESS of data having a normal frequency distribution is theoretically consistent with (Gaussian) truncated (additive, self-affine, monofractal) fractional Brownian motion (tfBm), the latter being unique in predicting a breakdown in power-law scaling at small and large lags, and (b) nonlinear power-law scaling of data having either normal or heavy-tailed frequency distributions is consistent with samples from sub-Gaussian random fields or processes subordinated to tfBm, stemming from lack of ergodicity which causes sample moments to scale differently than do their ensemble counterparts. Here we (i) demonstrate that the above two data sets are consistent with sub-Gaussian random fields subordinated to tfBm and (ii) provide maximum likelihood estimates of parameters characterizing the corresponding Lévy stable subordinators and tfBm functions.
Changes in Köppen-Geiger climate types under a future climate for Australia: hydrological implications
Authors: Crosbie R. S. , Pollock D. W. , Mpelasoka F. S. , Barron O. V. , Charles S. P. , Donn M. J.
Published: June 2012

Abstract. The Köppen-Geiger climate classification has been used for over a century to delineate climate types across the globe. As it was developed to mimic the distribution of vegetation it may provide a useful surrogate for making projections of the future distribution of vegetation, and hence resultant hydrological implications, under climate change scenarios. This paper developed projections of the Köppen-Geiger climate types covering the Australian continent for a 2030 and 2050 climate relative to a 1990 historical baseline climate using 17 Global Climate Models (GCMs) and five global warming scenarios. At the highest level of classification for a +2.4 °C future climate (the upper limit projected for 2050) relative to the historical baseline, it was projected that the area of the continent covered by: – Tropical climate types would increase from 8.8% to 9.1% – Arid climate types would increase from 76.5% to 81.7% – Temperate climate types would decrease from 14.7% to 9.2% – Cold climate types would decrease from 0.016% to 0.001%. Previous climate change impact studies on water resources in Australia have assumed a static vegetation distribution. If the change in projected climate types is used as a surrogate for a change in vegetation, then the major transition in climate from Temperate to Arid in parts of Australia under a drier future climate could cause indirect effects on water resources. For a transition from annual cropping to perennial grassland this would have a compounding effect on the projected reduction in recharge. In contrast, a transition from forest to grassland would have a mitigating effect on the projected reduction in runoff.
Measuring Mathematical Knowledge for Teaching Fractions With Drawn Quantities
Authors: Izsák Andrew , Jacobson Erik , de Araujo Zandra , Orrill Chandra Hawley
Published: June 2012

Researchers have recently used traditional item response theory (IRT) models to measure mathematical knowledge for teaching (MKT). Some studies (e.g., Hill, 2007; Izsák, Orrill, Cohen, & Brown, 2010), however, have reported subgroups when measuring middle-grades teachers' MKT, and such groups violate a key assumption of IRT models. This study investigated the utility of an alternative called themixture Rasch modelthat allows for subgroups. The model was applied to middle-grades teachers' performance on pretests and posttests bracketing a 42-hour professional development course focused on drawn models for fraction arithmetic. Results from psychometric modeling and evidence from video-recorded interviews and professional development sessions suggested that there were 2 subgroups of middle-grades teachers, 1 better able to reason with 3-level unit structures and 1 constrained to 2-level unit structures. Some teachers, however, were easier to classify than others.
Coming to Understand the Formal Definition of Limit: Insights Gained From Engaging Students in Reinvention
Authors: Swinyard Craig , Larsen Sean
Published: June 2012

The purpose of this article is to elaborate Cottrill et al.'s (1996) conceptual framework of limit, an explanatory model of how students might come to understand the limit concept. Drawing on a retrospective analysis of 2 teaching experiments, we propose 2 theoretical constructs to account for the students' success in formulating and understanding a definition of limit. The 1st construct relates to the need for students to move away from their tendency to attend first to the input variable of the function. The 2nd construct relates to the need for students to overcome the practical impossibility of completing an infinite process. Together, these 2 theoretical constructs build on Cottrill et al.'s work, resulting in a revised conceptual framework of limit.
Surfactant‐Free One‐Step Synthesis of Dual‐Functional Polyurea Microcapsules: Contact Infection Control and Drug Delivery
Authors: He Wei , Gu Xiaochen , Liu Song
Published: June 2012

Surface functionalized polyurea microcapsules (MCQ) are synthesized in one step. Dimethyl‐dodecyl‐(5‐hydroxy‐pentyl)‐ammonium bromide (DAB), a hydroxyl‐end‐capped quaternary ammonium salt, is synthesized and adopted as a new surfmer for the synthesis of MCQ. It is confirmed by fluorescein adsorption that DAB is covalently bonded to MCQ. The so‐formed MCQ possess dual‐functionality: contact infection control and sustained drug delivery. Agar diffusion antimicrobial tests confirm successful inhibition of multi‐drug‐resistant E. coli by MCQ alone instead of by leaching of free quaternary ammonium salts. Furthermore, few E. coli colonies survive on an agar plate coated with 3–4 layers of MCQ. Dissolution tests show a typical first‐order release profile of courmarin‐1, a model dye, from MCQ.
Equilibrium and kinetics analysis of carbon dioxide capture using immobilized amine on a mesoporous silica
Authors: Monazam Esmail R. , Shadle Lawrence J. , Miller David C. , Pennline Henry W. , Fauth Daniel J. , Hoffman James S. , Gray McMahan L.
Published: June 2012

Thermogravimetric analysis is used to study the adsorption kinetics, equilibrium, and thermodynamics of CO2 on immobilized polyethylenimine sorbent impregnated on a mesoporous silica over the range of 300–390 K and 5–100% CO2 concentration. Adsorption isotherm models were fitted to the experimental data indicating that a change in adsorption mechanism occurred near 70°C. Below this temperature, the adsorption data followed the heterogeneous isotherms, while data taken at higher‐temperatures followed isotherms for homogeneous surfaces. Heat of sorption was estimated to be 130 kJ/mole for the low‐temperature regime, but this decreased to 48 kJ/mole above 70°C. The rate of CO2 fractional uptake decreased as temperature increased. A phenomenological kinetic model was derived from the Weibull distribution function using a nucleation growth theory to describe the two‐step process. The kinetic model was used to predict the uptake at different operating conditions and resulted in good agreement with experimental data. Published 2012 American Institute of Chemical Engineers AIChE J, 2013
Factors associated with risky sun exposure behaviors among operating engineers
Authors: Duffy Sonia A. , Choi Seung Hee , Hollern Rachael , Ronis David L.
Published: June 2012

Background

The objective of this study was to determine the factors associated with sun exposure behaviors among Operating Engineers (heavy equipment operators).

Methods

Operating Engineers (N = 498) were asked to complete a cross‐sectional survey. Linear and logistic regression analyses were used to determine health behavioral, perceptional, and demographic factors associated with sun exposure behavior (sun burns, blistering, use of sunscreen, and interest in sun protection services).

Results

Almost half reported two or more sunburns/summer and the median times blistering was 2 with a range of 0–100. About one‐third never used sun block, while just over one‐third rarely used sun block. Almost one‐quarter were interested in sun protection guidance. Multivariate analyses showed that perceptions of skin type, alcohol problems, fruit intake, BMI, sleep quality, age, sex, and race were significantly associated with at least one of the outcome variables (P < 0.05).

Conclusions

Operating Engineers are at high risk for skin cancer due to high rates of exposure to ultraviolet light and low rates of sun block use. Subgroups of Operating Engineers are particularly at risk for sun damage. Interventions are needed to decrease sun exposure among Operating Engineers. Am. J. Ind. Med. 55:786–792, 2012. © 2012 Wiley Periodicals, Inc.
Serotonin transporter5‐HTTLPRgenotype moderates the effects of childhood adversity on posttraumatic stress disorder risk: A replication study
Authors: Xie Pingxing , Kranzler Henry R. , Farrer Lindsay , Gelernter Joel
Published: June 2012

We reported that the5‐HTTLPRpolymorphism in the promoter region of the serotonin transporter gene (SLC6A4) moderates the effect of childhood adversity on posttraumatic stress disorder (PTSD) risk [Xie et al. (2009); Arch Gen Psychiatry 66 (11): 1201–1209]. In the present study, we considered 5,178 subjects (a group with generally high substance dependence comorbidity, as for our previous study) using similar methodology to replicate our previous results. We used logistic regression analyses to explore the interaction effect of5‐HTTLPRgenotype and childhood adversity on PTSD risk. We found that, as reported in our previous study, in individuals with childhood adversity, the presence of one or two copies of theSallele of5‐HTTLPRincreased the risk to develop PTSD. This gene–environment interaction effect was present in European Americans (EAs), but not in African Americans (AAs; EAs, OR = 1.49, 95% CI = 1.07–2.08,P = 0.019; AAs, OR = 0.90, 95% CI = 0.60–1.35,P = 0.62). The statistical power to detect this interaction effect was increased when data were combined with those from our previous study [Xie et al. (2009); Arch Gen Psychiatry 66 (11): 1201–1209]. The findings reported here replicate those from our previous work, adding to a growing body of research demonstrating that the5‐HTTLPRgenotype moderates risk for anxiety and depression phenotypes in the context of stress and adverse events. © 2012 Wiley Periodicals, Inc.
Defining genetically meaningful language and personality traits in relatives of individuals with fragile X syndrome and relatives of individuals with autism
Authors: Losh Molly , Klusek Jessica , Martin Gary E. , Sideris John , Parlier Morgan , Piven Joseph
Published: June 2012

Substantial phenotypic overlap exists between fragile X syndrome (FXS) and autism, suggesting thatFMR1(the gene causing FXS) poses a significant risk for autism. Cross‐population comparisons of FXS and autism therefore offer a potentially valuable method for refining the range of phenotypes associated with variation inFMR1. This study adopted a broader phenotype approach, focusing on parents who are at increased genetic liability for autism or FXS. Women who were carriers ofFMR1in its premutation state were compared with mothers of individuals with autism, and controls in an attempt to determine whether subtle features of the broad autism phenotype may express at elevated rates amongFMR1premutation carriers. The principal personality and language features comprising the broad autism phenotype (i.e., rigid and aloof personality, and particular patterns of pragmatic language use) were assessed among 49 premutation carriers who were mothers of individuals with FXS, 89 mothers of individuals with autism, and 23 mothers of typically developing individuals. Relative to controls, the autism and premutation parent groups showed elevated rates of certain personality and language characteristics of the broad autism phenotype. Findings suggest partially overlapping personality and language profiles among autism and premutation parent groups, with rigid personality style and patterns of pragmatic language use emerging as features most clearly shared between groups. These results provide further evidence for the overlap of autism and FXS, and may implicateFMR1in some of the subtle features comprising the broad autism phenotype. © 2012 Wiley Periodicals, Inc.