bluuebunny/crossref_metadata_2025 huggingface dataset:
MRI‐based Morphometric Analysis of Posterior Cranial Fossa in the Diagnosis of Chiari Malformation Type I
Authors: Urbizu Aintzane , Poca Maria‐Antonia , Vidal Xavier , Rovira Alex , Sahuquillo Juan , Macaya Alfons
Published: January 2013

BACKGROUND AND PURPOSE

The diagnosis of Chiari malformation type I (CMI) relies on MRI identification of a tonsillar descent (TD) through the foramen magnum, reflecting the overcrowding of an underdeveloped posterior cranial fossa (PCF). However, TD occurs in some patients with normal‐sized PCF and, conversely, some patients with borderline or no TD have small PCF. We thus sought to identify a set of prototypic PCF measures for the diagnosis of CMI.

METHODS

We performed nineteen measurements of the PCF on sagittal MRI of 100 cases with cerebellar TD ≥5 mm and 50 control individuals, compared the average values in both cohorts and used logistic regression to devise a probability model to predict CMI status.

RESULTS

Significant decrements were detected for several PCF‐related measures in the patients’ cohort. We developed a probability model that combined seven of these parameters to predict diagnosis with 93% sensitivity and 92% specificity.

CONCLUSIONS

The addition of simple morphometric measurements in the diagnostic work‐up of patients with suspected CMI may facilitate radiological diagnosis. Moreover, identification of the subset of CMI that arise from basichondrocranium underdevelopment is important for both, selection of the most appropriate therapeutic approach as well as proper CMI categorization in research studies.
Effect of 12-oxochenodeoxycholate on the pharmacokinetics and pharmacodynamics of morphine 6-glucuronide in Wistar rats
Authors: Yang Lin , Fawcett J Paul , Zhang Hu , Tucker Ian G
Published: January 2013

Objectives

The semi-synthetic bile salt, 12-oxochenodeoxycholate (OCDC also known as 12-monoketocholate), has been shown to enhance drug permeation across biological membranes with low cytotoxicity. Its effect on the analgesic potency and brain concentration of morphine 6-glucuronide (M6G) was studied in male Wistar rats.

Methods

Four groups of animals (n = 8) were given 5, 10 or 20 mg/kg OCDC or normal saline (control) by subcutaneous injection 30 min before a subcutaneous injection of 5 mg/kg M6G after which the hotplate test was performed on each rat at various times. After a 2 week wash-out period, the same rats (n = 30) were randomized to two equal groups and given OCDC (20 mg/kg) or normal saline 30 min before 5 mg/kg M6G. At five time points up to 3 h after M6G administration, three rats from each group were euthanized and blood and brain analyzed for M6G.

Key findings

The area under the analgesic effect versus time curve (AUAE) was found to be significantly (P < 0.05) greater in rats given 20 mg/kg OCDC than in control rats. Area under the curve (AUC) for M6G in both plasma and brain was greater in OCDC-treated rats than in control rats, but the brain : plasma AUC ratio was lower.

Conclusions

OCDC enhances the analgesic effect of M6G but gives a lower brain : plasma ratio due to increasing M6G plasma levels probably by reducing its renal clearance.
Potential Adverse Effects of Omega‐3 Fatty Acids in Dogs and Cats
Authors: Lenox C.E. , Bauer J.E.
Published: January 2013

Fish oil omega‐3 fatty acids, mainly eicosapentaenoic acid and docosahexaenoic acid, are used in the management of several diseases in companion animal medicine, many of which are inflammatory in nature. This review describes metabolic differences among omega‐3 fatty acids and outlines potential adverse effects that may occur with their supplementation in dogs and cats with a special focus on omega‐3 fatty acids from fish oil. Important potential adverse effects of omega‐3 fatty acid supplementation include altered platelet function, gastrointestinal adverse effects, detrimental effects on wound healing, lipid peroxidation, potential for nutrient excess and toxin exposure, weight gain, altered immune function, effects on glycemic control and insulin sensitivity, and nutrient‐drug interactions.
An autopsied case of Creutzfeldt‐Jakob disease with mutation in the prion protein gene codon 232 and type 1+2 prion protein
Authors: Iwasaki Yasushi , Yokoi Fuji , Tatsumi Shinsui , Mimuro Maya , Iwai Katsushige , Kitamoto Tetsuyuki , Yoshida Mari
Published: January 2013

A 68‐year‐old Japanese man gradually showed abnormal behavior and gait disturbance with bradykinesia. Slowly progressive dementia, including memory disturbance and disorientation, was also observed. Cerebral cortical hyperintensity on diffusion‐weighted MRI was observed 6 months after onset. The patient progressed to an akinetic mutism state with mild myoclonus, and atypical periodic sharp‐wave complexes were observed by electroencephalogram 13 months after onset. He was clinically suspected of having atypical CJD and died after 19 months total disease duration. The brain weighed 1160 g and showed mild atrophy of the cerebrum and cerebellum with ventricular dilatation. Spongiform changes with varying vacuole size and gliosis was extensive in the cerebral cortex and basal ganglia. Neuron loss in the cerebral cortex, basal ganglia and thalamus was relatively mild. The cerebellum showed mild spongiform changes of the molecular layer and mild neuron loss in the Purkinje cell layer. PrP immunostaining showed mainly coarse‐type combined with diffuse synaptic‐type PrP deposition in the cerebral gray matter. Some perivacuolar‐type PrP deposition was also present. Numerous plaque‐type PrP depositions were observed in the molecular layer of the cerebellum. Analysis of the PrP gene revealed a methionine‐to‐arginine (Met‐to‐Arg) substitution at codon 232 (M232R) with Met homozygosity at codon 129. Western blot analysis of protease‐resistant PrP indicated type 2 dominant PrP combined with type 1. Genetic CJD with M232R substitution in the PrP gene has only been reported in Japan. Although two clinical phenotypes (rapid‐type and slow‐type) were suggested in the M232R CJD cases (despite the presence of the same PrP genotype), the pathological and molecular backgrounds have not been well understood because there have only been a few autopsied case reports. This is the first case report of M232R CJD presenting with 1 + 2 PrP.
Productive engagement in older adults: A concept analysis
Authors: Thanakwang Kattika , Isaramalai Sang‐arun
Published: January 2013

This study aimed to clarify the concept of productive engagement as it applies to older adults. The concept analysis was based onWalker andAvant's eight‐step method. A literature review of articles published inEnglish between 1990 and 2011 (n = 37) was conducted, using an electronic search of multiple sources. Results revealed that four defining attributes for productive engagement include continuing to work either paid or unpaid, caring for others, engaging in social activities, and growing spirituality. The antecedents of productive engagement are sociocultural factors as well as individual and institutional capacities. Meanwhile, the consequences are increased feelings of usefulness, improved health and well‐being, aged successfully, and enhanced quality of life. Model, borderline, and contrary cases are presented to illustrate the concept's defining attributes. Defining the concept of productive engagement provides a basis for nurses and other health professionals to better understand productive engagement in older adults, thus effective strategic plans or programs for promoting productive roles among older adults can be further developed.
Arabidopsis COLD SHOCK DOMAIN PROTEIN 2 is a negative regulator of cold acclimation
Authors: Sasaki Kentaro , Kim Myung‐Hee , Imai Ryozo
Published: January 2013

Bacterial cold shock proteins (CSPs) act as RNA chaperones that destabilize mRNA secondary structures at low temperatures. Bacterial CSPs are composed solely of a nucleic acid‐binding domain termed the cold shock domain (CSD). Plant CSD proteins contain an auxiliary domain in addition to the CSD but also show RNA chaperone activity. However, their biological functions are poorly understood.

We examined Arabidopsis COLD SHOCK DOMAIN PROTEIN 2 (AtCSP2) using overexpressing and mutant lines.

A double mutant, with reduced AtCSP2 and no AtCSP4, showed higher freezing tolerance than the wild‐type when cold‐acclimated. The increase in freezing tolerance was associated with up‐regulation of CBF transcription factors and their downstream genes. By contrast, overexpression of AtCSP2 resulted in decreased freezing tolerance when cold‐acclimated. In addition, late flowering and shorter siliques were observed in the overexpressing lines.

AtCSP2 negatively regulates freezing tolerance and is partially redundant with its closest paralog, AtCSP4.
Reduction of molecular gas diffusion through gaskets in leaf gas exchange cuvettes by leaf‐mediated pores
Authors: BOESGAARD KRISTINE S. , MIKKELSEN TEIS N. , RO‐POULSEN HELGE , IBROM ANDREAS
Published: January 2013

There is an ongoing debate on how to correct leaf gas exchange measurements for the unavoidable diffusion leakage that occurs when measurements are done in non‐ambient CO2 concentrations. In this study, we present a theory on how the CO2 diffusion gradient over the gasket is affected by leaf‐mediated pores (LMP) and how LMP reduce diffusive exchange across the gaskets. Recent discussions have so far neglected the processes in the quasi‐laminar boundary layer around the gasket. Counter intuitively, LMP reduce the leakage through gaskets, which can be explained by assuming that the boundary layer at the exterior of the cuvette is enriched with air from the inside of the cuvette. The effect can thus be reduced by reducing the boundary layer thickness. The theory clarifies conflicting results from earlier studies. We developed leaf adaptor frames that eliminate LMP during measurements on delicate plant material such as grass leaves with circular cross section, and the effectiveness is shown with respiration measurements on a harp of Deschampsia flexuosa leaves. We conclude that the best solution for measurements with portable photosynthesis systems is to avoid LMP rather than trying to correct for the effects.
Madness as Balancing Act in Joseph Brodsky's “Gorbunov and Gorchakov”
Authors: REICH REBECCA
Published: January 2013

This article examines the psychological connotations of Joseph Brodsky's “art of estrangement” in light of the psychiatric evaluations the poet underwent in 1963 and 1964 and his depiction of madness in the poem “Gorbunov and Gorchakov” (1965–68). Several years before the punitive uses of Soviet psychiatry came to the attention of samizdat readers, Brodsky was forced to weigh the dangers and benefits of psychiatric diagnosis in his dealings with the state. The balance that he struck is mirrored in “Gorbunov and Gorchakov,” in which the state's claim that “being determines consciousness” and Brodsky's claim that the “estranged” consciousness determines being are personified and placed in dialogue. The poem, which is set in a psychiatric hospital, indicates that the “art of estrangement” can lead to madness if consciousness strikes out too far on its own. By engaging with being in life and work, Brodsky kept consciousness grounded for the sake of sanity and self‐definition.
Was the Gulag an Archipelago? De‐Convoyed Prisoners and Porous Borders in the Camps of Western Siberia
Authors: BELL WILSON T.
Published: January 2013

This article focuses on the issue of de‐convoyed (raskonvoirovannye) prisoners in order to argue that Aleksandr Solzhenitsyn's enduring analogy for the Gulag—the archipelago—is, in many instances, misleading. The practice of allowing significant numbers of prisoners to move, unguarded, outside of the camp zones was widespread throughout the Stalin era, and is especially interesting as a topic of study for Western Siberia, an area where the largest camp subdivisions were located within the city limits of major urban centers, such as Novosibirsk and Tomsk. This article is the first systematic study of the phenomenon during the Stalin era, and assesses the rules of and reasons for de‐convoyed status, prisoners' thoughts concerning unguarded movement, and problems and opportunities (including black market activity) arising from the widespread presence of unescorted prisoners. Ultimately, the Gulag's porous borders meant that Gulag space was not separate, isolated space, despite the best intentions of the regime.
Oral health care provided by Greek dentists to persons with physical and/or intellectual impairment
Authors: Gizani Sotiria , Kandilorou Helen , Kavvadia Katerina , Tzoutzas John
Published: January 2013

Purpose

The study aimed to register information about the oral health care provided to persons with physical and intellectual impairment (PPII) in Greece and to report the dentists’ attitudes towards the provision of oral health care.

Methods

A well‐designed questionnaire was used to select information on dentists’ socioeconomic data, their office characteristics, the performed oral health care and their views about oral health care delivery for PPII. The final sample consisted of 534 dentists. Descriptive statistics and Analysis of Variance (ANOVA) has been used for the statistical analysis of the data.

Results

Most respondents were general practitioners (79.3%) providing oral health care to PPII, but seven out of ten dentists have not been trained to treat them. According to their opinion, oral health care for PPII demands a lot of time and is hard to accomplish.

Conclusions

Continuing education and training of dentists to treat PPII is essential in Greece.
Effortlessly strengthening infant memory: Associative potentiation of new learning
Authors: ROVEE‐COLLIER CAROLYN , MITCHELL KATHERINE , HSU‐YANG VIVIAN
Published: January 2013

Rovee‐Collier, C., Mitchell, K. & Hsu‐Yang, V. (2013). Effortlessly strengthening infant memory: Associative potentiation of new learning. Scandinavian Journal of Psychology 54, 4–9.

We recently discovered that young infants learn a new association better in the presence of a prior association than when they learn it alone – a phenomenon we call associative potentiation. When 6‐month‐olds observed actions modeled on a puppet (remembered for 1 day) in the presence of a toy train they had learned to activate (remembered for 2 weeks), they remembered the demonstration for 2 weeks too. Currently, we examined the generality of associative potentiation. We found that when 6‐month‐olds learned the train task (remembered for 5 days) in the presence of two previously associated puppets (remembered for 4 weeks); they remembered the train task for 4 weeks too – more than five times longer. We conclude that associative potentiation is a general phenomenon: Cues for any stronger prior association will correspondingly increase the memory strength of any weaker new association that young infants learn in their presence, eliminating the need for repeated practice. We view associative potentiation as an adaptive mechanism that counteracts the rapid forgetting of younger infants by instantly increasing the strength of their new learning to a level characteristic of older infants. Neuromaturational models of infant memory cannot account for associative potentiation, but an ecological model does.
Soil organic carbon as affected by land use in young and old reclaimed regions of a coastal estuary wetland, China
Authors: Bai J. , Xiao R. , Zhang K. , Gao H. , Cui B. , Liu X.
Published: January 2013

Soil organic carbon (SOC) and selected soil properties were measured in fringe and ditch marshes and cropland of old and young reclaimed areas in a subtropical estuary in China in order to investigate the effects of land use and reclamation history on SOC. The results show that after the conversion of wetlands to cropland, a longer reclamation history (>20 yr) resulted in greater soil bulk density, salinity, clay and silt, and lower soil moisture, SOC and sand content, whereas a shorter reclamation history (<20 yr) induced smaller values for soil pH, moisture and sand. Ditch marshes had greater average SOC in the top 50 cm than fringe marshes and cropland. SOC decreased generally down soil profiles from 0 to 50 cm in depth, except for the obvious accumulation of SOC in deeper soils from old fringe and young ditch marshes. Ditch marshes had the greatest SOC densities in the top 50 cm in both regions compared to the other land uses. SOC densities in the top 50 cm were less in croplands than in fringe marshes in the young region, while there were no significant differences between them in the older one. Except for cropland, SOC densities in the top 50 cm of the fringe or ditch marshes in the old region were not significantly different from those in the young region. SOC in both regions was reduced by 13.53 × 104 t (12.98%) in the top 50 cm of the marshes after conversion to cropland, whereas the regional SOC storage increased by 29.25 t when ditch marshes were included. The results from regression analysis show that bulk density and soil moisture significantly influenced SOC. The total SOC stored in both ditch marshes and croplands was higher compared to fringe marshes. The regional SOC storage in the top 50 cm was not reduced after reclamation due to C accumulation in the ditch marshes. The regional effects of cultural practices should be taken into account in devising strategies for managing soils in coastal wetlands, particularly in the developing world.
Blood transfusions and the subsequent risk of cancers in the United States elderly
Authors: Riedl Regina , Engels Eric A. , Warren Joan L. , Berghold Andrea , Ricker Winnie , Pfeiffer Ruth M.
Published: January 2013

Background

Blood transfusions are common in older adults and also may modulate the immune system. However, the impact of transfusion on cancer risk in the elderly has not been studied.

Study Design and Methods

Cancer risk after blood transfusion was evaluated in a US population‐based case–control study using 552,951 elderly cases identified from cancer registries and 100,000 frequency‐matched controls. Transfusions received 0 to 12, 13 to 30, and 31 to 48 months before cancer diagnosis or selection date were identified using Medicare claims. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using logistic regression models. A Bonferroni correction adjusted for multiple testing.

Results

Transfusions received 0 to 12 months before cancer diagnosis and/or selection were associated with significantly elevated risk of cancer overall (OR, 2.05; 95% CI, 1.95‐2.16) and cancer of the stomach; cancer of the colon; cancer of the liver, kidney, renal pelvis, and/or ureter; lymphoma; myeloma; and leukemia. No significant associations for cancer overall were observed for the two earlier intervals. No site was associated with transfusions received 13 to 30 or 31 to 48 months before diagnosis and/or selection. Nonetheless, overall cancer risk increased with the number of transfused periods (p‐trend < 0.0001).

Conclusion

Risk of overall cancer and specific sites was elevated 0 to 12 months after blood transfusion and associated with multiple transfusions, possibly due to reverse causation, that is, incipient cancers or cancer precursors causing anemia.
Recovery, safety, and tolerability of a solvent/detergent‐treated and prion‐safeguarded transfusion plasma in a randomized, crossover, clinical trial in healthy volunteers
Authors: Jilma‐Stohlawetz Petra , Kursten Friedrich W. , Horvath Michaela , Leitner Gerda , List Jana , Marcek Jana , Quehenberger Peter , Schwameis Michael , Bartko Johann , Derhaschnig Ulla , Jilma Bernd
Published: January 2013

Background

Octaplas LG is a prion‐depleted version of a previous generation product called Octaplas S/D. We compared the recovery, safety, and tolerability of these two pharmaceutical‐grade plasmas.

Study Design and Methods

In this comparative, block‐randomized, open‐label, active‐controlled, crossover Phase I trial, 60 healthy adult volunteers received single transfusions of 1200 mL of parent product (in Period 1) and of the LG plasma product (in Period 2) or vice versa. In both periods, plasmapheresis (600 mL) preceded the transfusion. Blood samples were drawn before and after apheresis and 15 minutes, 2 hours, 24 hours, and 7 days after end of plasma transfusion, to assess recovery, safety, and tolerability. The primary efficacy endpoints were the changes in coagulation factors and hemostatic variables compared to baseline; their relative recovery was computed in the per‐protocol analysis (n = 43). Safety and tolerability were assessed (n = 60).

Results

Variations in coagulation factors and hemostatic variables over time were similar between the two treatments and within normal range; 90% confidence intervals for the derived recovery data were within predefined limits of equivalence. Both products were well tolerated. The advanced manufacturing process also significantly increased plasmin inhibitor concentrations after transfusion in vivo.

Conclusion

The LG plasma product was bioequivalent to its predecessor with respect to recovery of clotting factors and demonstrated comparable safety and tolerability in healthy volunteers. Both products compensated well for the loss of clotting factors after apheresis (NCT01063595).
Viability of umbilical cord blood mononuclear cell subsets until 96 hours after collection
Authors: Pereira‐Cunha Fernanda G. , Duarte Adriana S.S. , Costa Fernando F. , Saad Sara T.O. , Lorand‐Metze Irene , Luzo Angela C.M.
Published: January 2013

Background

Umbilical cord blood (UCB) is a good source of hematopoietic stem cells for transplantation and cell therapy. In 2006, the Brazilian Public Network of Cord Blood Banks was founded; however, because our country is large, logistic problems could hamper the collection of numerous samples. Our aim was to evaluate the viability of several UCB cell subsets until 96 hours after collection, to examine whether this delay would be acceptable for processing and freezing the samples.

Study Design and Methods

Two experiments were performed: in the first one, volume reduction of the UCB units was carried out before analysis. In the second one, analysis was carried out with no previous manipulation. Samples were stored at room temperature and one aliquot was taken daily for analysis. We examined CD34+ cell, B‐cell precursor, mature B and T lymphocyte, monocyte, granulocyte, and mesenchymal stem cell (MSCs) concentrations.

Results

Thirty‐six UCB units were analyzed. CD34+ cells and mature T lymphocytes increased (viability 99%). Mature B lymphocytes and MSCs decreased, maintaining viability. Granulocytes decreased with loss of viability. Monocytes and immature B lymphocytes remained stable. Clonogenic assays showed a decrease in colony‐forming unit (CFU) number in UCB units stored for 96 hours.

Conclusion

UCB manipulation did not influence cell viability. All cell subsets remained viable until 96 hours after collection. CD34+ cells and T lymphocytes increased, probably due to the loss of other subsets. CFU growth during the period analyzed and confirmed stem cell functionality, despite the decrease at 96 hours. Results demonstrated that UCB units could probably be processed up to 96 hours after collection.
Storage of red blood cells affects membrane composition, microvesiculation, and in vitro quality
Authors: Almizraq Ruqayyah , Tchir Jayme D.R. , Holovati Jelena L. , Acker Jason P.
Published: January 2013

Background

During storage detrimental biochemical and biomechanical changes occur within a red blood cell (RBC). RBC microparticles (RMPs) produced during storage have been identified as biomarkers of RBC quality, being potentially immunogenic and inhibitory to nitric oxide regulation.

Study Design and Methods

In this study, microvesiculation and changes in the composition of the RBC membrane were investigated throughout 49 days of storage and were correlated with in vitro assays examining membrane quality. Leukoreduced RBC units produced using the buffy coat method were collected and stored at 1 to 6°C and were tested weekly for hemolysis, osmotic fragility, deformability, ATP, hematologic indices, and morphology. Microvesiculation was assessed using multicolor flow cytometry. High‐performance liquid chromatography and mass spectrometry were used to determine the composition and quantity of phospholipids (PLs) and cholesterol (C) on Days 2 and 43.

Results

The assessment of RBCs throughout storage revealed significant increases in percent hemolysis, while significant decreases in ATP concentrations, and the mean corpuscular hemoglobin concentration were observed. Flow cytometry analysis revealed a significant increase in the mean number of microparticles per microliter during storage. Throughout storage, significant decreases were identified in the amount of PLs and total lipids within the RBC membrane. No significant change in the amount of C in the RBC membrane was identified.

Conclusion

Significant changes to the RBC membrane occur during storage. The length of storage will influence RMP generation, osmotic fragility, hemolysis, and changes in deformability. These changes in RBC in vitro quality may contribute to transfusion reactions and negative posttransfusion outcomes.
Iron and cardiac ischemia: a natural, quasi‐random experiment comparing eligible with disqualified blood donors (CME)
Authors: Germain Marc , Delage Gilles , Blais Claudia , Maunsell Elizabeth , Décary Francine , Grégoire Yves
Published: January 2013

Background

The theory that elevated iron stores can induce vascular injury and ischemia remains controversial. We conducted a cohort study of the effect of blood donation on the risk of coronary heart disease (CHD) by taking advantage of the quasi‐random exclusion of donors who obtained a falsely reactive test for a transmissible disease (TD) marker.

Study Design and Methods

Whole blood donors who were permanently disqualified because of a false‐reactive test between 1990 and 2007 in the province of Quebec were compared to donors who remained eligible, matched for baseline characteristics. The incidence of CHD after entry into the study was determined through hospitalization and death records. We compared eligible and disqualified donors using an “intention‐to‐treat” framework.

Results

Overall, 12,357 donors who were permanently disqualified were followed for 124,123 person‐years of observation, plus 50,889 donors who remained eligible (516,823 person‐years). On average, donors who remained eligible made 0.36 donation/year during follow‐up and had an incidence of hospitalizations or deaths attributable to CHD of 3.60/1000 person‐years, compared to 3.52 among permanently disqualified donors (rate ratio, 1.02; 95% confidence interval, 0.92‐1.13).

Conclusion

Donors who remained eligible did not have a lower risk of CHD, compared to donors who were permanently disqualified due to a false‐reactive TD marker. Because of the quasi‐random nature of false‐reactive screening tests, this natural experiment has a level of validity approaching that of a randomized trial evaluating the effect of regular blood donation on CHD risk. These results do not support the iron hypothesis.
Water Spout
Authors: Greenslade Thomas B.
Published: January 2013

During the AAPT summer meeting at Creighton University in 2011, Vacek Miglus and I took pictures of early apparatus at the Creighton physics department. The apparatus in the left-hand picture, shown with the spigot closed, appeared to be a liquid-level device: the water level was the same in both the narrow tube and the flaring glass vase. However, when I came back nine months later to give a talk about the apparatus, I realized that it was really an early Bernoulli effect demonstration. In the right-hand picture the spigot is open and water can be seen coming out of the spout. The water level in the narrow tube has fallen appreciably, thus showing that the pressure at this point has decreased, in agreement with the non-zero velocity of the water in the horizontal tube. The device was made ca. 1880 by E. S. Ritchie of Boston, MA. (Photos by Thomas B. Greenslade Jr.)
A Resource for Using Real-World Examples in the Physics Classroom
Authors: Van Dongen Janelle , Rieger Georg
Published: January 2013

Physics Teaching for the 21st Century (://c21.phas.ubc.ca) is a free online resource for teachers who are interested in teaching physics concepts in real-world contexts. The materials on this site were developed by a team of physics faculty and graduate and undergraduate students at the Department of Physics & Astronomy, University of British Columbia, based on issues of great current concern—reusable energy, climate change, and medical advancement. Topics on the website also focus on applications of physics in the natural world around us. There are currently about 70 different topics on the website and it is not possible to justly give a sense of the website in total here. Instead we will present one complete example of the resources available on our website and show how it can be used in the classroom or in lecture. The example discussed here1 is suitable for a first-year university course and focuses on diffraction through a circular aperture and Rayleigh's resolution criterion by looking at the effect of pupil size on the minimum angle of resolution. The original idea came from reading a book on zoological physics,2 and a short example was later found in a first-year physics textbook.3
Self-reported “best” resources for teachers
Authors: White Susan
Published: January 2013

In over 80% of the schools where physics is taught, there is only one teacher teaching the subject, so most teachers cannot readily turn to a colleague at their schools for answers or suggestions about issues that deal specifically with physics. When physics teachers do have questions about physics content, the most often reported “best” source for answers is the Internet. Potentially demonstrating a better personal network or a better familiarity with the resources available to them, teachers who had completed physics education courses were significantly less likely to use their class texts as the best answer source. Instead, they were more likely to rely on college or university teachers. Having access to resources beyond the class text can help teachers develop a more nuanced understanding of physics concepts, as well as a better sense of perspective about the content they teach.
Using comics to increase literacy and assess student learning
Authors: Schwaller Terry
Published: January 2013

Formative assessment strategies and the integration of literacy pose two of the many hurdles teachers face. With the pressure of standardized test scores hanging over everyone's heads, finding class time to integrate these essential strategies is at a premium. By integrating comics with quick, formative written assessment, you can kill the proverbial two birds with one stone.
Prenatal Cerebral Ischemia Disrupts MRI-Defined Cortical Microstructure Through Disturbances in Neuronal Arborization
Authors: Dean Justin M. , McClendon Evelyn , Hansen Kelly , Azimi-Zonooz Aryan , Chen Kevin , Riddle Art , Gong Xi , Sharifnia Elica , Hagen Matthew , Ahmad Tahir , Leigland Lindsey A. , Hohimer A. Roger , Kroenke Christopher D. , Back Stephen A.
Published: January 2013

Preterm ischemia disrupts MRI-defined maturation of the cerebral cortex by impairing the differentiation of cortical neurons in fetal lambs.
Brain Maturation After Preterm Birth
Authors: Molnár Zoltán , Rutherford Mary
Published: January 2013

Two translational studies—one in humans and one in sheep—suggest that premature birth is associated with delayed maturation of brain grey matter and that promoting growth in these neonates can boost brain development.
Cancer Vaccines: Targeting an Infectious Cause
Authors: Barnabas Ruanne V.
Published: January 2013

Estimating the percentage of cancers caused by infectious agents could bolster development of better vaccines.
Flavin Electron Shuttles Dominate Extracellular Electron Transfer by Shewanella oneidensis
Authors: Kotloski Nicholas J. , Gralnick Jeffrey A.
Published: January 2013

Shewanella oneidensisstrain MR-1 is widely studied for its ability to respire a diverse array of soluble and insoluble electron acceptors. The ability to breathe insoluble substrates is defined as extracellular electron transfer and can occur via direct contact or by electron shuttling inS. oneidensis. To determine the contribution of flavin electron shuttles in extracellular electron transfer, a transposon mutagenesis screen was performed withS. oneidensisto identify mutants unable to secrete flavins. A multidrug and toxin efflux transporter encoded by SO_0702 was identified and renamedbfe(bacterialflavin adenine dinucleotide [FAD]exporter) based on phenotypic characterization. Deletion ofbferesulted in a severe decrease in extracellular flavins, while overexpression ofbfeincreased the concentration of extracellular flavins. Strains lackingbfehad no defect in reduction of soluble Fe(III), but these strains were deficient in the rate of insoluble Fe(III) oxide reduction, which was alleviated by the addition of exogenous flavins. To test a different insoluble electron acceptor, graphite electrode bioreactors were set up to measure current produced by wild-typeS. oneidensisand the Δbfemutant. With the same concentration of supplemented flavins, the two strains produced similar amounts of current. However, when exogenous flavins were not supplemented to bioreactors,bfemutant strains produced significantly less current than the wild type. We have demonstrated that flavin electron shuttling accounts for ~75% of extracellular electron transfer to insoluble substrates byS. oneidensisand have identified the first FAD transporter in bacteria.

IMPORTANCEExtracellular electron transfer by microbes is critical for the geochemical cycling of metals, bioremediation, and biocatalysis using electrodes. A controversy in the field was addressed by demonstrating that flavin electron shuttling, not direct electron transfer or nanowires, is the primary mechanism of extracellular electron transfer employed by the bacteriumShewanella oneidensis. We have identified a flavin adenine dinucleotide transporter conserved in all sequencedShewanellaspecies that facilitates export of flavin electron shuttles inS. oneidensis. Analysis of a strain that is unable to secrete flavins demonstrated that electron shuttling accounts for ~75% of the insoluble extracellular electron transfer capacity inS. oneidensis.
Gene doping: an overview and current implications for athletes
Authors: van der Gronde Toon , de Hon Olivier , Haisma Hidde J , Pieters Toine
Published: January 2013

The possibility of gene doping, defined as the transfer of nucleic acid sequences and/or the use of normal or genetically modified cells to enhance sport performance, is a real concern in sports medicine. The abuse of knowledge and techniques gained in the area of gene therapy is a form of doping, and is prohibited for competitive athletes. As yet there is no conclusive evidence that that gene doping has been practiced in sport. However, given that gene therapy techniques improve continuously, the likelihood of abuse will increase.

A literature search was conducted to identify the most relevant proteins based on their current gene doping potential using articles from Pubmed, Scopus and Embase published between 2006 and 2011. The final list of selected proteins were erythropoietin, insulin-like growth factor, growth hormone, myostatin, vascular endothelial growth factor, fibroblast growth factor, endorphin and enkephalin, α actinin 3, peroxisome proliferator-activated receptor-delta (PPARδ) and cytosolic phosphoenolpyruvate carboxykinase (PEPCK-C). We discuss these proteins with respect to their potential benefits, existing gene therapy experience in humans, potential risks, and chances of detection in current and future anti-doping controls.

We have identified PPARδ and PEPCK-C as having high potential for abuse. But we expect that for efficiency reasons, there will be a preference for inserting gene target combinations rather than single gene doping products. This will also further complicate detection.
Identifying optimal postmarket surveillance strategies for medical and surgical devices: implications for policy, practice and research
Authors: Gagliardi Anna R , Umoquit Muriah , Lehoux Pascale , Ross Sue , Ducey Ariel , Urbach David R
Published: January 2013

Background

Non-drug technologies offer many benefits, but have been associated with adverse events, prompting calls for improved postmarket surveillance. There is little empirical research to guide the development of such a system. The purpose of this study was to identify optimal postmarket surveillance strategies for medical and surgical devices.

Methods

Qualitative methods were used for sampling, data collection and analysis. Stakeholders from Canada and the USA representing different roles and perspectives were first interviewed to identify examples and characteristics of different surveillance strategies. These stakeholders and others they recommended were then assembled at a 1-day nominal group meeting to discuss and prioritise the components of a postmarket device surveillance system, and research needed to achieve such a system.

Results

Consultations were held with 37 participants, and 47 participants attended the 1-day meeting. They recommended a multicomponent system including reporting by facilities, clinicians and patients, supported with some external surveillance for validation and real-time trials for high-risk devices. Many considerations were identified that constitute desirable characteristics of, and means by which to implement such a system. An overarching network was envisioned to broker linkages, establish a shared minimum dataset, and support communication and decision making. Numerous research questions were identified, which could be pursued in tandem with phased implementation of the system.

Discussion

These findings provide unique guidance for establishing a device safety network that is based on existing initiatives, and could be expanded and evaluated in a prospective, phased fashion as it was developed.
Network and satellite arrangements in liver disease
Authors: O'Grady John G
Published: January 2013

Liver disease has evolved into a complex discipline with several tiers of service delivery. Patients’ needs vary at different phases of their disease, with mobility between local hospitals and specialist centres being increasingly common. Liver transplantation requirements serve as a good illustration of this fluidity and the need for service providers to coordinate care delivery. This is facilitated by the development of networks and satellite relationships that can range in complexity and functionality.
Prevalence of sleepiness while driving four-wheel motor vehicles in Fiji: a population-based survey (TRIP 9)
Authors: Herman Josephine , Ameratunga Shanthi N , Wainiqolo Iris , Kafoa Berlin , Robinson Elizabeth , McCaig Eddie , Jackson Rod
Published: January 2013

Introduction

Sleepiness has been shown to be a risk factor for road crashes in high-income countries, but has received little attention in low- and middle-income countries. We examined the prevalence of sleepiness and sleep-related disorders among drivers of four-wheel motor vehicles in Fiji.

Method

Using a two-stage cluster sampling roadside survey conducted over 12 months, we recruited a representative sample of people driving four-wheel motor vehicles on the island of Viti Levu, Fiji. A structured interviewer-administered questionnaire sought self-report information on driver characteristics including sleep-related measures.

Results

The 752 motor vehicle drivers recruited (84% response rate) were aged 17–75 years, with most driving in Viti Levu undertaken by male subjects (93%), and those identifying with Indian (70%) and Fijian (22%) ethnic groups. Drivers who reported that they were not fully alert accounted for 17% of driving, while a further 1% of driving was undertaken by those who reported having difficulty staying awake or feeling sleepy. A quarter of the driving time among 15–24-year-olds included driving while sleepy or not fully alert, with a similar proportion driving while chronically sleep deprived (ie, with less than five nights of adequate sleep in the previous week=27%). Driving while acutely or chronically sleep deprived was generally more common among Fijians compared with Indians.

Conclusions

Driving while not fully alert is relatively common in Fiji. Sleepiness while driving may be an important contributor to road traffic injuries in this and other low- and middle-income countries.
Bathroom injuries in children less than 15 years old
Authors: Head Elizabeth Nicole , Stevens Judy A , Haileyesus Tadesse
Published: January 2013

Objective

To quantify and describe non-fatal, unintentional bathroom injuries among children less than 15 years of age treated in US hospital emergency departments (EDs).

Methods

This study used 2008 data from a nationally representative sample of EDs, available from the National Electronic Injury Surveillance System-All Injury Program. We examined unintentional non-fatal bathroom injuries in any setting (eg, home, school or public place) among children less than 15 years of age and identified types of injuries, major locations within the bathroom and precipitating events.

Results

Based on 1099 cases, an estimated 51 132 non-fatal bathroom injuries in children less than 15 years of age were treated in US EDs in 2008. Most injuries (73.8%) were caused by falls. The highest rate was for injuries that occurred in or around the shower or bathtub (65.9 per 100 000). Children less than 15 years of age sustained the greatest number of injuries and had the highest injury rate (151 per 100 000 (95% CI 108.7 to 193.3)), while children 10–14 years of age had the lowest rate (28.7 (95% CI 20.6 to 36.8)). The rates differed significantly by age group (p<0.001). A majority of the patients (96.9%) were treated in the ED and released.

Conclusions

Most bathroom injuries in children occurred while they were showering or bathing and were caused by falling or hitting an object. Such injuries might be reduced by improving caregiver supervision for younger children. For older children, a combination of bathroom safety education and environmental modifications, such as installing grab bars inside and outside the shower or tub, may reduce bathroom injuries.
Misclassification of suicide deaths: examining the psychiatric history of overdose decedents
Authors: Bohnert Amy S B , McCarthy John F , Ignacio Rosalinda V , Ilgen Mark A , Eisenberg Anna , Blow Frederic C
Published: January 2013

Objectives

The intent of a death from overdose can be difficult to determine. The goal of this study was to examine the association of psychiatric diagnoses among overdose deaths ruled by a medical examiner as intentional, unintentional and indeterminate intent.

Methods

All Veterans Health Administration patients in Fiscal Year 1999 (n=3 291 891) were followed through Fiscal Year 2006. We tested the relative strength of association between psychiatric disorders among types of overdoses (categorised by intent) using multinomial models, adjusted for age, sex, Veterans Affairs priority status and Charlson comorbidity scores. Data were from National Death Index records and patient medical records.

Results

Substance use disorders (SUD) had a stronger association with indeterminate intent overdoses than intentional overdoses (adjusted OR (AOR)=1.80, 95% CI 1.47 to 2.22). SUDs also had a stronger association with unintentional overdoses than intentional (AOR=1.48, 95% CI 1.27 to 1.72), but the reverse was true for all other psychiatric disorders (except post-traumatic stress disorder).

Conclusions

Overdoses ruled indeterminate may be misclassified suicide deaths and are important to suicide surveillance and prevention efforts. Additionally, overdose deaths not classified as suicides may include some cases due to suicidal-like thinking without overt suicidal intent.
Expression and diagnostic relevance of heat shock protein 90 and signal transducer and activator of transcription 3 in malignant pheochromocytoma
Authors: Xu Yunze , Qi Yicheng , Rui Wenbin , Zhu Yu , Zhang Chongyu , Zhao Juping , Wei Qing , Wu Yuxuan , Shen Zhoujun , Ning Guang
Published: January 2013

Background

Malignant pheochromocytoma (PCC) is a rare catecholamine producing tumour with a poor prognosis. For many years predicting PCC behaviour has remained a highly difficult task. The aim of this study was to evaluate heat shock protein 90 (HSP90) and signal transducer and activator of transcription 3 (STAT3) as tissue-based markers to predict malignant PCC.

Methods

Ninety-two sporadic PCC patients were enrolled. We compared the expression of HSP90 and STAT3 by immunohistochemistry of benign versus malignant PCCs. In addition, in 17 snap frozen PCC and in 7 healthy adrenal tissues, we investigated the expression of HSP90 and STAT3 by means of western immunoblot.

Results

Positive staining for HSP90 was observed in 22.37% (95% CI 13.00% to 31.74%) of the benign and 66.67% (95% CI 44.89% to 88.45%) of the malignant cases. Similarly, STAT3 staining was seen in 26.32% (95% CI 16.42% to 36.22%) of the benign versus 83.33% (95% CI 66.11% to 100.55%) of the malignant cases. Using HSP90 and STAT3 combined, the positive predictive value of malignancy was signiﬁcantly increased to 0.70 (95% CI 0.45 to 0.86). Besides, logistic regression analysis showed that HSP90 (OR=3.667, p=0.039) and STAT3 (OR=9.474, p=0.002) were independently associated with malignant PCC.

Conclusions

This study has conﬁrmed that malignant PCC overexpress HSP90 and STAT3, and the combination of HSP90 and STAT3 can be used as helpful diagnostic markers to distinguish malignant from benign PCCs.
Occurrence and significance of epithelial-mesenchymal transition in breast cancer
Authors: Roxanis Ioannis
Published: January 2013

By contrast with developmental epithelial-mesenchymal transition (EMT), where epithelial characteristics undergo transformation to a mesenchymal-like phenotype in a coordinated fashion, oncogenic EMT occurs in the context of unpredictable genetic changes present in the tumour cells, as well as an abnormal tumour microenvironment. Therefore, a partial form of EMT has been proposed as variably participating in the establishment of invasive phenotype in different types of breast carcinoma, in keeping with their morphological and phenotypical diversity. A complex network of signalling pathways and transcription factors appears responding to various growth factors and cytokines released by stromal and neoplastic elements, endowing the system with abundant regulatory opportunities. The process of EMT is largely elusive in histopathological preparations, prompting doubts regarding its significance in tumour progression. This might be related to the presumed focal occurrence of EMT in the majority of tumours. Detailed topological studies might facilitate understanding of the orchestration of events taking place in vivo. Even more importantly, clinical correlations can be endeavoured and, in parallel with advancement in molecular pathology, a contribution to taxonomy refinement can be envisaged.
Superior vena cava stenting in the 21st century
Authors: Warner Parveen , Uberoi Raman
Published: January 2013

Superior vena cava obstruction (SVCO) is most commonly due to malignant or thrombotic causes. The traditional treatments of surgery, radiotherapy or chemotherapy either have a high morbidity and mortality rate, or a lag period of a few weeks prior to response. Superior vena cava stenting is able to provide rapid relief of symptoms safely in the vast majority of patients. It has now become the first-line treatment for malignant SVCO, and is increasingly being used in benign SVCO. The complication and success rates compare very favourably with the other treatment modalities.