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Background Children with deprivation amblyopia due to childhood cataract have been excluded from much of the emerging research into amblyopia treatment. An investigation was conducted to determine whether contrast-balanced binocular treatment - a strategy currently being explored for children with anisometropic and strabismic amblyopia - may be effective in children with deprivation amblyopia. Methods An unmasked, case-series design intended to assess proof of principle was employed. Eighteen children with deprivation amblyopia due to childhood cataracts (early bilateral n = 7, early unilateral n = 7, developmental n = 4), as well as 10 children with anisometropic (n = 8) or mixed anisometropic and strabismic amblyopia (n = 2) were prescribed one hour a day of treatment over a six-week period. Supervised treatment was available. Visual acuity, contrast sensitivity, global motion perception and interocular suppression were measured pre- and post-treatment. Results Visual acuity improvements occurred in the anisometropic/strabismic group (0.15 ± 0.05 logMAR, p = 0.014), but contrast sensitivity did not change. As a group, children with deprivation amblyopia had a smaller but statistically significant improvement in weaker eye visual acuity (0.09 ± 0.03 logMAR, p = 0.004), as well a significant improvement in weaker eye contrast sensitivity (p = 0.004). Subgroup analysis suggested that the children with early bilateral deprivation had the largest improvements, while children with early unilateral cataract did not improve. Interestingly, binocular contrast sensitivity also improved in children with early bilateral deprivation. Global motion perception improved for both subgroups with early visual deprivation, as well as children with anisometropic or mixed anisometropic/strabismic amblyopia. Interocular suppression improved for all subgroups except children with early unilateral deprivation. Conclusion These data suggest that supervised contrast-balanced binocular treatment should be further investigated as a treatment option for children with deprivation amblyopia. However, for children with more severe deprivation amblyopia due to early unilateral cataracts, supplementary or alternative options should also be explored.

Graphene, which is a two-dimensional crystal of carbon atoms arranged in a hexagonal lattice, has attracted a great amount of attention due to its outstanding mechanical, thermal and electronic properties. Moreover, graphene shows an exceptionally strong tunable light-matter interaction that depends on the Fermi level - a function of chemical doping and external gate voltage - and the electromagnetic resonance provided by intentionally engineered structures. In the optical regime, the nonlinearities of graphene originated from the Pauli blocking have already been exploited for mode-locking device applications in ultrafast laser technology, whereas nonlinearities in the terahertz regime, which arise from a reduction in conductivity due to carrier heating, have only recently been confirmed experimentally. Here, we investigated two key factors for controlling nonlinear interactions of graphene with an intense terahertz field. The induced transparencies of graphene can be controlled effectively by engineering meta-atoms and/or changing the number of charge carriers through electrical gating. Additionally, nonlinear phase changes of the transmitted terahertz field can be observed by introducing the resonances of the meta-atoms.

Simple beliefs about our ability to influence life events are powerful. Perceived control acts as a cognitive resource to preserve and promote resilience and goal engagement. It cultivates overall quality of life, protecting us when adversity strikes, and it plays a self-regulatory role when pursuing goals. In this chapter, we discuss key developments in the perceived control literature and review empirical findings that provide insights into what qualifies (moderates) and explains (mediates) the role of control beliefs and strategies in fostering well being and goal pursuit. We conclude by describing future applied research that aims to instill perceived control.

Our quasi-experimental, longitudinal treatment study examined whether Attributional Retraining (AR) facilitated adjustment among young adults (n = 324) making the challenging school-to-university transition. An AR by performance orientation group 2 × 4 design showed AR primarily benefited high-risk students: Failure-ruminators (high failure preoccupation, low perceived control) receiving AR reported higher intrinsic motivation and more adaptive attribution-related emotions than their no-AR peers. Failure-acceptors (low failure preoccupation, low perceived control) receiving AR had higher intrinsic motivation, higher grade point averages, and fewer course withdrawals than their no-AR counterparts. Thus, AR had differential benefits (emotions, achievement) for vulnerable students who were psychologically distinct.

We describe a balance beam aid for instruction in diagnosis (BBAID) and demonstrate its potential use in supplementing the training of medical students to diagnose acute chest pain. We suggest the BBAID helps students understand the process of diagnosis because the impact of tokens (weights and helium balloons) attached to a beam at different distances from the fulcrum is analogous to the impact of evidence to the relative support for 2 diseases. The BBAID presents a list of potential findings and allows students to specify whether each is present, absent, or unknown. It displays the likelihood ratios corresponding to a positive (LR+) or negative (LR–) observation for each symptom, for any pair of diseases. For each specified finding, a token is placed on the beam at a location whose distance from the fulcrum is proportional to the finding’s log(LR): a downward force (a weight) if the finding is present and a lifting force (a balloon) if it is absent. Combining the physical torques of multiple tokens is mathematically identical to applying Bayes’ theorem to multiple independent findings, so the balance beam is a high-fidelity metaphor. Seven first-year medical students and 3 faculty members consulted the BBAID while diagnosing brief patient case vignettes. Student comments indicated the program is usable, helpful for understanding pertinent positive and negative findings’ usefulness in particular situations, and welcome as a reference or self-test. All students attended the effect of the tokens on the beam, although some stated they did not use the numerical statistics. Faculty noted the BBAID might be particularly helpful in reminding students of diseases that should not be missed and identifying pertinent findings to ask for.

A new method of preparation of golden-yellow, microcrystalline, and air-sensitive single-phase cerium(III) oxide, Ce2O3, from CeO2 and Ce was developed. Solid solutions (Ce1–xLax)O2–0.5x (0 < x < 0.55) in the system CeO2-La2O3 and (Ce1–xLax)2O3 (0 < x < 1) in the system Ce2O3-La2O3 were synthesized and investigated by means of X-ray powder diffraction.

The authors present a theoretical analysis of metallic strip surface plasmon nano-lasers that are compatible with III–V semiconductor materials and fabrication technologies. The design mimics a ridge waveguide laser, where the ridge is a metallic strip that sits on top of a semiconductor slab waveguide. We discuss the formation and characteristics of a mode that is bound to the metallic strip and evaluate the possibility of compensating its propagation loss with the gain from the semiconductor slab. We find that the bound mode is a hybrid of the modes of the metallic strip and those of the semiconductor slab and that by varying the internal coupling, it is possible to engineer extremely strong lateral mode confinement while also mitigating the high propagation losses that are typically associated with surface plasmon modes. Using a realistic gain model for GaAs and a new analysis of the confinement factor, we find that carrier concentrations in the region of 3 × 1018 cm−3 can compensate for the bound mode's propagation losses, in the region of 1000 cm−1, at room temperature. This design has many desirable features including single lateral mode operation, a high confinement-to-loss figure of merit and the potential for relatively straightforward in-situ fabrication.

The physical basis for how macromolecules regulate the onset of mineral formation in calcifying tissues is not well established. A popular conceptual model assumes the organic matrix provides a stereochemical match during cooperative organization of solute ions. In contrast, another uses simple binding assays to identify good promoters of nucleation. Here, we reconcile these two views and provide a mechanistic explanation for template-directed nucleation by correlating heterogeneous nucleation barriers with crystal-substrate-binding free energies. We first measure the kinetics of calcite nucleation onto model substrates that present different functional group chemistries (carboxyl, thiol, phosphate, and hydroxyl) and conformations (C11 and C16 chain lengths). We find rates are substrate-specific and obey predictions of classical nucleation theory at supersaturations that extend above the solubility of amorphous calcium carbonate. Analysis of the kinetic data shows the thermodynamic barrier to nucleation is reduced by minimizing the interfacial free energy of the system, γ. We then use dynamic force spectroscopy to independently measure calcite-substrate-binding free energies, ΔGb. Moreover, we show that within the classical theory of nucleation, γ and ΔGb should be linearly related. The results bear out this prediction and demonstrate that low-energy barriers to nucleation correlate with strong crystal-substrate binding. This relationship is general to all functional group chemistries and conformations. These findings provide a physical model that reconciles the long-standing concept of templated nucleation through stereochemical matching with the conventional wisdom that good binders are good nucleators. The alternative perspectives become internally consistent when viewed through the lens of crystal-substrate binding.

ZusammenfassungEine chronische subklinische Entzündung des Fettgewebes, charakterisiert durch ein proinflammatorisches Adipokin-Sekretionsmuster und durch die Infiltration von Entzündungszellen, trägt zu verschiedenen mit der Adipositas verbundenen Stoffwechselstörungen bei. Die langkettigen Omega-3-Fettsäuren Eicosapentaensäure (EPA) und Docosahexaensäure (DHA) wirken inflammatorischen Prozessen im Fettgewebe entgegen, und zwar sowohl auf Stufen der Entwicklung als auch bei der Auflösung der Entzündung. EPA und DHA stellen Substrate für kürzlich identifizierte Familien von entzündungsauflösenden Lipid-Mediatoren dar, speziell von Resolvinen, Protektinen und Maresinen, denen eine wesentliche Rolle in der Begrenzung von Entzündungen zukommt.Als eine Strategie zur Prävention systemischer, mit der Adipositas assoziierter Komplikationen ist es notwendig, die inflammatorischen Prozesse im Fettgewebe günstig zu beeinflussen. Zahlreiche Untersuchungen haben ergeben, dass langkettige Omega-3-Fettsäuren hierzu beitragen und dass die Verfügbarkeit von EPA und DHA das Risiko von Adipositas-assoziierten Stoffwechselerkrankungen verringert. Deshalb ist die Versorgung mit langkettigen Omega-3-Fettsäuren sowohl auf Bevölkerungsebene als auch speziell für adipöse Personen bedeutsam.

Meta-cognitive awareness, or self reflection informed by the “heuristics and biases” theory of how experts make cognitive errors, has been offered as a partial solution for diagnostic errors in medicine. I argue that this approach is not as easy nor as effective as one might hope. We should also promote mastery of the basic principles of diagnosis in medical school, continuing medical education, and routine reflection and review. While it may seem difficult to attend to both levels simultaneously, there is more to be gained from attending to both than from focusing only on one.

IntroductionGlobally, there are an estimated 370 million Indigenous people across 90 countries. Indigenous people experience worse health compared with non-Indigenous people, including higher rates of avoidable visual impairment. Countries such as Australia and Canada have service delivery models aimed at improving access to eye care for Indigenous people. We will conduct a scoping review to identify and summarise these service delivery models to improve access to eye care for Indigenous people in high-income countries.Methods and analysisAn information specialist will conduct searches on MEDLINE, Embase and Global Health. All databases will be searched from their inception date with no language limits used. We will search the grey literature via websites of relevant government and service provider agencies. Field experts will be contacted to identify additional articles, and reference lists of relevant articles will be searched. All quantitative and qualitative study designs will be eligible if they describe a model of eye care service delivery aimed at Indigenous populations. Two reviewers will independently screen titles, abstracts and full-text articles; and complete data extraction. For each service delivery model, we will extract data on the context, inputs, outputs, Indigenous engagement and enabling health system functions. Where models were evaluated, we will extract details. We will summarise findings using descriptive statistics and thematic analysis.Ethics and disseminationEthical approval is not required, as our review will include published and publicly accessible data. This review is part of a project to improve access to eye care services for Māori in Aotearoa New Zealand. The findings will be useful to policymakers, health service managers and clinicians responsible for eye care services in New Zealand, and other high-income countries with Indigenous populations. We will publish our findings in a peer-reviewed journal and develop an accessible summary of results for website posting and stakeholder meetings.

Purpose Reliable estimation of visual acuity requires that observers maintain a constant distance from the target, but use of chin rests is not always feasible. Our aim was to quantify children's movement during community testing and its impact on near (40 cm) and intermediate (150 cm) acuity measures. Methods Thirty-three 7-year-old children performed several acuity tests run on a tablet computer, administered in the child's home by a trained lay screener. The tablet webcam was used to derive a continuous estimate of the child's position during testing. We estimated acuity using both the recommended viewing distance and using trial-by-trial estimates of the child's physical distance from the screen. Results Although initial positioning in the 40-cm viewing distance condition was accurate, on 18% of trials children moved sufficiently to support a 0.1 logMAR improvement in acuity, leading 16% of staircases to overestimate acuity by more than one line. Initial positioning for the 150-cm condition was less accurate, but the longer viewing distance minimized the impact of children's movement on the visual angle of the target. Overall, at 150 cm 8% of staircases were overestimated by more than 0.1 logMAR. Conclusions Children move substantially during intermediate and near acuity tests despite assessors encouraging maintenance of the correct viewing distance. Translational Relevance Real-time estimates of the child's physical distance from the target are possible when assessments are conducted on camera-enabled devices. Correction for movement will likely lead to more accurate measures of near and intermediate visual acuity.

PurposeTo understand how we might improve the provision of medical care for children with cataracts.DesignA phenomenological design was employed. Semi-structured interviews were conducted to capture rich descriptions of the phenomena. Our goal in the interview and the analysis was to understand the sources of distress associated with treatment for cataract and deprivation amblyopia which (1) could be addressed by the medical community and (2) related to treatment adherence.SettingInterviews were conducted by a non-clinician researcher in New Zealand (NZ) in a location chosen by informants. In NZ, the red reflex screening test is performed shortly after birth, and surgery to remove paediatric cataracts is publicly funded.ParticipantsFamilies of children who had a history of cataract in Auckland, NZ were posted an invitation to participate. Twenty families were interviewed.ResultsOur analysis illustrated that informants described a wide range of experiences, from declined cataract surgery to full adherence to medical advice including years of patching for more than 4 hours a day. Across these experiences, we identified three relevant themes; timing of diagnosis, communication between the parent and clinician, and parental social support networks.ConclusionThe medical community may be better placed to support families dealing with childhood cataract by improving detection of childhood cataract, building appropriate communication pathways and promoting social support, with an emphasis on empathetic, individualised care.

Researchers used a kindergarten screening to identify kindergarten students at risk for difficulties in reading (phonological awareness) and writing (fine motor and perceptual skills) prior to beginning the school year. Of the 102 incoming kindergarten students, 54 showed signs of reading or writing difficulties. These 54 children participated in a weekly enrichment program called KidSkills. A collaborative team of educators developed the program with the intent to subscribe to the response-to-intervention approach. The KidSkills program used small-group intervention to address students’ developmental differences in literacy skills and overall academic readiness. Researchers tracked students’ progress using the Dynamic Indicators of Basic Early Literacy Skills, Scott Foresman Baseline Group Test, and Early Literacy Profile in the fall, winter, and spring of the school year. All students who received the intervention demonstrated gains in literacy and fine motor and perceptual skills, and by May the entire...

Here we present a minimal mathematical model for the sphingomyelin synthase 1 (SMS1) driven conversion of ceramide to sphingomyelin based on chemical reaction kinetics. We demonstrate via mathematical analysis that this model is not able to qualitatively reproduce experimental measurements on lipid compositions after altering SMS1 activity. We prove that a positive feedback mechanism from the products to the reactants of the reaction is one possible model extension to explain these specific experimental data. The proposed mechanism in fact exists in vivo via protein kinase D and the ceramide transfer protein CERT. The model is further evaluated by additional observations from the literature.

The purpose of this study was to investigate the extent to which correlated neural inputs, quantified as EMG-EMG coherence across intrinsic and extrinsic hand muscles, varied as a function of wrist angle during a constant force precision grip task. Eight adults (5 males; mean age 29 years) participated in the experiment. Subjects held an object using a two-digit precision grip at a constant force at a flexed, neutral, and extended wrist posture, while the EMG activity from intrinsic and extrinsic hand muscles was recorded through intramuscular fine-wire electrodes. The integral of z-transformed coherence computed across muscles pairs was greatest in the flexed wrist posture and significantly greater than EMG-EMG coherence measured in the neutral and extended wrist posture (P < 0.01 and 0.05, respectively). Furthermore, EMG-EMG coherence did not differ statistically between the extrinsic and intrinsic muscle pairs, even though it tended to be greater for the extrinsic muscle pair (P ≥ 0.063). These findings lend support to the notion of a functional role of correlated neural inputs to hand muscles for the task-dependent coordination of hand muscle activity that is likely mediated by somatosensory feedback.

Transitions to novel achievement settings are often accompanied by unfamiliar learning conditions and unanticipated failure that undermine how individuals adapt to such situations. For first-year students, the transition to college is imbued with adverse learning conditions that can result in decreased motivation and academic performance. This study examined the efficacy of a motivation-enhancing treatment, attributional retraining (AR), to assist students who are at risk because of a high-failure avoidance orientation (tendency to maintain self-worth by avoiding failure). For high- (but not low) failure avoidance students, AR fostered an adaptive psychological mindset (course grade expectations, judgments of course responsibility) and better academic performance (course grade, grade point average). Findings suggest the utility of AR to offset the negative effects of a high-failure avoidance self-worth orientation.

Developmental transitions are imbued with ubiquitous uncertainties that undermine goal striving in many otherwise committed individuals. Our seven-month study examined whether cognitive selective secondary control strategies (motivation-focused thinking) facilitate the enactment of achievement goals among young adults experiencing the landmark school to university transition. Sequential regression analyses demonstrated that (a) achievement goals predicted selective secondary control, (b) selective secondary control predicted behavioral selective primary control striving, and (c) selective primary control predicted final course grades. Findings support Heckhausen et al.'s (2010) proposition that selective secondary control bolsters selective primary control striving and enables goal attainment during difficult transitions.

When a college professor who teaches research methods to graduate education students was approached by a local public urban elementary school to help them teach research skills to 4th-graders, we t...

Graphene, as a 2D semi-metal, is able to support surface plasmon modes. These plasmons interact, scattering the electrons in graphene, by way of emission and absorption. For electrons in thermal equilibrium, the energy scale of the optical response can be tuned by setting the Fermi level via external gate voltage. However, for non-equilibrium cases, such as photo-excitation, plasmons can become amplified through stimulated emission. We present how the non-local sheet conductivity can be calculated for graphene in non-equilibrium cases, how this affects the plasmon dispersion, as well as absorption and emission rates, and how the plasmon channel contributes to carrier relaxtion.

Introduction Chronic lower back pain (CLBP) is a major healthcare problem with wide ranging effects. It is a priority for appropriate management of CLBP to get individuals back to work as early as possible. Interventions that identify biopsychosocial barriers to recovery have been observed to lead to successfully reduced pain-related work absences and increased return to work for individuals with CLBP. Modern conceptualisations of pain adopt a biopsychosocial approach, such as the flags approach. Biopsychosocial perspectives have been applied to judgements about future adjustment, recovery from pain and risk of long-term disability; and provide a helpful model for understanding the importance of contextual interactions between psychosocial and biological variables in the experience of pain. Medical students and general practitioner (GP) trainees are important groups to target with education about biopsychosocial conceptualisations of pain and related clinical implications. Aim The current study will compare the effects of an e-learning intervention that focuses on a biopsychosocial model of pain, on the clinical judgements of medical students and trainees. Methods and analysis Medical student and GP trainee participants will be randomised to 1 of 2 study conditions: (1) a 20 min e-learning intervention focused on the fundamentals of the flags approach to clinical judgement-making regarding risk of future pain-related disability; compared with a (2) wait-list control group on judgement accuracy and weighting (ie, primary outcomes); flags approach knowledge, attitudes and beliefs towards pain, judgement speed and empathy (ie, secondary outcomes). Participants will be assessed at preintervention and postintervention. Ethics and dissemination The study will be performed in agreement with the Declaration of Helsinki and is approved by the National University of Ireland Galway Research Ethics Committee. The results of the trial will be published according to the CONSORT statement and will be presented at conferences and reported in peer-reviewed journals. Trial registration number ISRCTN53670726; Pre-results.

Research has established the health benefits of psychological factors, including the way individuals appraise outcomes. Although many studies confirm that appraising outcomes as controllable is adaptive for health, a paradoxical possibility is largely ignored: Perceived control may be detrimental under some conditions. Our premise was that appraising health as controllable but at the same time ascribing little value to it might signal a dysfunctional psychological mindset that fosters a mistaken sense of invincibility. During face-to-face interviews with a representative sample of older adults (age range = 72–99), we identified individuals with such a potentially maladaptive “invincible” mindset (high perceived control and low health value) and compared them to their counterparts on several outcomes. The findings were consistent with our hypotheses. The invincibles denied future risks, they lacked the activating emotion of fear, and they visited their physicians less often over a subsequent five-year period. Moreover, in contrast to their counterparts, the invincibles did not appear strategic in their approach to seeking care: Even poor health did not prompt them to seek the counsel of a physician. The recognition that psychological appraisals are modifiable highlights the promise of remedial methods to alter maladaptive mindsets, potentially improving quality of life.

The fast decay of carrier inversion in photoexcited graphene has been attributed to optical phonon emission and Auger recombination. Plasmon emission provides another pathway that, as we show here, drives the carrier relaxation dynamics on ultrafast time scales. In studying the nonequilibrium relaxation dynamics we find that plasmon emission effectively converts inversion into hot carriers, whose energy is then extracted by optical phonon emission. This mechanism not only explains the observed femtosecond lifetime of inversion but also offers the prospect for atomically thin ultrafast plasmon emitters, This work has been funded by the Engineering and Physical Sciences Research Council (United Kingdom), the Leverhulme Trust (United Kingdom), the European Research Council (ERC- 2011-AdG Proposal No. 290981) and the Spanish MINECO (Grant No. MAT2011-28581-C02-01)

Nanoplasmonic metamaterials are an exciting new class of engineered media that promise a range of important applications, such as subwavelength focusing, cloaking, and slowing/stopping of light. At optical frequencies, using gain to overcome potentially not insignificant losses has recently emerged as a viable solution to ultra-low-loss operation that may lead to next-generation active metamaterials. Maxwell-Bloch models for active nanoplasmonic metamaterials are able to describe the coherent spatiotemporal and nonlinear gain-plasmon dynamics. Here, we extend the Maxwell-Bloch theory to a Maxwell-Bloch Langevin approach-a spatially resolved model that describes the light field and noise dynamics in gain-enhanced nanoplasmonic structures. Using the example of an optically pumped nanofishnet metamaterial with an embedded laser dye (four-level) medium exhibiting a negative refractive index, we demonstrate the transition from loss-compensation to amplification and to nanolasing. We observe ultrafast relaxation oscillations of the bright negative-index mode with frequencies just below the THz regime. The influence of noise on mode competition and the onset and magnitude of the relaxation oscillations is elucidated, and the dynamics and spectra of the emitted light indicate that coherent amplification and lasing are maintained even in the presence of noise and amplified spontaneous emission.

Plasmonic metamaterials form an exciting new class of engineered media that promise a range of important applications, such as subwavelength focusing, cloaking and slowing/stopping of light. Recently it has been shown that the internal losses due to the natural absorption of metals at optical frequencies can be compensated by gain. Here, we employ a Maxwell–Bloch methodology which allows us to study the dynamics of the coherent plasmon-gain interaction, nonlinear saturation, field enhancement and radiative damping. Using numerical pump-probe experiments on a double-fishnet metamaterial with dye-molecule inclusions we investigate the buildup of the inversion and the formation of the plasmonic modes in the low-Q fishnet cavity. We find that loss compensation occurs in the negative-refractive-index regime and that, due to the loss compensation and the associated sharpening of the resonance, the real part of the refractive index of the metamaterial becomes more negative compared to the passive case. Furthermore, we investigate the behavior of the metamaterial above the lasing threshold, and we identify the occurrence of a far-field lasing burst and gain depletion. Our results provide deep insight into the internal processes that affect the macroscopic properties of active metamaterials. This could guide the development of amplifying and lasing plasmonic nanostructures.

The hyperexcitability of alpha-motoneurons and accompanying spasticity following spinal cord injury (SCI) have been attributed to enhanced persistent inward currents (PICs), including L-type calcium and persistent sodium currents. Factors controlling PICs may offer new therapies for managing spasticity. Such factors include calcium-activated potassium (KCa) currents, comprising in motoneurons an after-hyperpolarization-producing current (I KCaN) activated by N/P-type calcium currents, and a second current (I KCaL) activated by L-type calcium currents (Li and Bennett in J neurophysiol 97:767-783, 2007). We hypothesize that these two currents offer differential control of PICs and motoneuron excitability based on their probable somatic and dendritic locations, respectively. We reproduced SCI-induced PIC enhancement in a two-compartment motoneuron model that resulted in persistent dendritic plateau potentials. Removing dendritic I KCaL eliminated primary frequency range discharge and produced an abrupt transition into tertiary range firing without significant changes in the overall frequency gain. However, I KCaN removal mainly increased the gain. Steady-state analyses of dendritic membrane potential showed that I KCaL limits plateau potential magnitude and strongly modulates the somatic injected current thresholds for plateau onset and offset. In contrast, I KCaN had no effect on the plateau magnitude and thresholds. These results suggest that impaired function of I KCaL may be an important intrinsic mechanism underlying PIC-induced motoneuron hyperexcitability following SCI.

Background: Breast cancer is an important public health issue within the American Indian (AI) community in Oklahoma; however, there is limited information to explain the low screening mammography rates among AI women. Purpose: To identify the motivational factors affecting an AI woman's decision to obtain a mammogram. Methods: Through the use of the Theory of Planned Behavior, 24 elicitation interviews were conducted with eligible for mammography AI women obtaining services at an Oklahoma-based tribal clinic. Results: Most women had mixed attitudes toward screening mammography. Environmental-related factors also were cited as barriers in getting a screening mammogram and women recommended improved accessibility to mammography screening. Participants identified family members, friends and their personal physician as critical social referents. No specific culturally related beliefs or taboos were noted. Discussion: This study provides new theoretically guided insights into the motivation of AI wome...

Coupled resonator optical waveguides (CROWs) have the potential to revolutionise integrated optics, to slow-light and enhance linear and non-linear optical phenomena. Here we exploit the broad resonances and subwavelength nature of localized surface plasmons in a compact CROW design where plasmonic nanoparticles are side coupled to a dielectric waveguide. The plasmonic CROW features a low loss central mode with a highly tunable dispersion, that avoids coupling to the plasmonic nanoparticles close to the band-edge. We show that this low loss character is preserved in finite plasmonic CROWs giving rise to Fabry-Perot type resonances that have high quality factors of many thousands, limited only by the CROW length. Furthermore we demonstrate that the proposed CROW design is surprisingly robust to disorder. By varying the geometric parameters one can not only reduce the losses into dissipative or radiative channels but also control the outcoupling of energy to the waveguide. The ability to minimise loss in plasmonic CROWs while maintaining dispersion provides an effective cavity design for chip-integrated laser devices and applications in linear and non-linear nano-photonics.

Spasticity is commonly observed after chronic spinal cord injury (SCI) and many other central nervous system disorders (e.g., multiple sclerosis, stroke). SCI-induced spasticity has been associated with motoneuron hyperexcitability partly due to enhanced activation of intrinsic persistent inward currents (PICs). Disrupted spinal inhibitory mechanisms also have been implicated. Altered inhibition can result from complex changes in the strength, kinetics, and reversal potential ( ECl−) of γ-aminobutyric acid A (GABAA) and glycine receptor currents. Development of optimal therapeutic strategies requires an understanding of the impact of these interacting factors on motoneuron excitability. We employed computational methods to study the effects of conductance, kinetics, and ECl− of a dendritic inhibition on PIC activation and motoneuron discharge. A two-compartment motoneuron with enhanced PICs characteristic of SCI and receiving recurrent inhibition from Renshaw cells was utilized in these simulations. This dendritic inhibition regulated PIC onset and offset and exerted its strongest effects at motoneuron recruitment and in the secondary range of the current-frequency relationship during PIC activation. Increasing inhibitory conductance compensated for moderate depolarizing shifts in ECl− by limiting PIC activation and self-sustained firing. Furthermore, GABAA currents exerted greater control on PIC activation than glycinergic currents, an effect attributable to their slower kinetics. These results suggest that modulation of the strength and kinetics of GABAA currents could provide treatment strategies for uncontrollable spasms.

A series of Mg-bearing synthetic amorphous calcium carbonates (ACC) were characterized by Raman spectroscopy. The spectra showed a systematic increase in the carbonate n1 peak position from the control samples that contained 0.0mol % MgCO3 to samples that contained up to 43mol % MgCO3. The relationship is best described by the function: mol % MgCO3=(n1 – 1079.66) / 0.2017. The Mg content is equally well-predicted by a correlation with the instrumentally corrected n1 full width at half maximum that is quantified by: mol % MgCO3=(n1 – 23.26) / 0.1969. An analysis of the Raman data collected for ACC combined with insights from crystalline materials suggests that compositional dependencies arise from changes in the local metal–oxygen bonds as Mg substitutes for Ca. The calibrations described here provide a rapid and nondestructive means of determining the Mg content of ACC, with additional advantages of minimal sample preparation and a high degree of lateral spatial resolution (approximately 1mm). This method may be appropriate for investigations of heterogeneous samples such as biominerals. Copyright © 2011 John Wiley & Sons, Ltd. Supporting information can be found in the online version of this article.

The primary purpose of this classroom experiment was to examine the effectiveness of concrete (hands-on) manipulatives as compared with virtual (computer-based) manipulatives on student review of fraction concepts in third grade and introduction of symmetry concepts in fourth grade. A pretest–posttest design was employed with a sample of 91 third-grade students and 54 fourth-grade students who were randomly assigned to complete a lesson using either concrete or virtual manipulatives. Students used a variety of manipulative materials during the lessons. Results of the posttest suggest that student learning was unchanged by lesson condition.

Fingertip force control requires fine coordination of multiple hand muscles within and across the digits. While the modulation of neural drive to hand muscles as a function of force has been extensively studied, much less is known about the effects of fatigue on the coordination of simultaneously active hand muscles. We asked eight subjects to perform a fatiguing contraction by gripping a manipulandum with thumb, index, and middle fingers while matching an isometric target force (40% maximal voluntary force) for as long as possible. The coordination of 12 hand muscles was quantified as electromyographic (EMG) muscle activation pattern (MAP) vector and EMG-EMG coherence. We hypothesized that muscle fatigue would cause uniform changes in EMG amplitude across all muscles and an increase in EMG-EMG coherence in the higher frequency bands but with an invariant heterogeneous distribution across muscles. Muscle fatigue caused a 12.5% drop in the maximum voluntary contraction force ( P < 0.05) at task failure and an increase in the SD of force ( P < 0.01). Although EMG amplitude of all muscles increased during the fatiguing contraction ( P < 0.001), the MAP vector orientation did not change, indicating that a similar muscle coordination pattern was used throughout the fatiguing contraction. Last, EMG-EMG coherence (0–35 Hz) was significantly greater at the end than at the beginning of the fatiguing contraction ( P < 0.01) but was heterogeneously distributed across hand muscles. These findings suggest that similar mechanisms are involved for modulating and sustaining digit forces in nonfatiguing and fatiguing contractions, respectively.

The present research examined whether remaining employed protected against nine-year declines in cognitive functioning (episodic memory). We used the national Midlife in the United States Study to (a) propensity score match middle-aged and older adults who remained employed with those who retired, (b) test whether the matched samples differed on longitudinal cognitive functioning, and (c) examine whether effects of work status were moderated by goal disengagement and sex. Comparisons of the matched samples indicated workers had slightly less decline in cognitive functioning than retirees, but this difference was not significant. Tests of moderation showed those who remained employed (vs. retired) exhibited more adaptive changes in cognitive functioning only if they were high in goal disengagement (b =.26, p =.019) or if they were female (b =.24, p =.022). Findings suggest that continued employment may protect against cognitive declines for women and those who are prone to goal disengagement after retirement.

Background: NOD2 single nucleotide polymorphisms have been associated with increased risk of ileal Crohn's disease (CD). This exploratory study was conducted to compare ileal mucosal gene expression in CD patients with and without NOD2 risk alleles. Methods: Ileal samples were prospectively collected from 18 nonsmoking CD patients not treated with anti-TNF-α biologics and 9 nonsmoking control patients without inflammatory bowel disease undergoing initial resection and genotyped for the 3 major NOD2 risk alleles (Arg702Trp, Gly908Arg, Leu1007fs). Microarray analysis was performed in samples from 4 NOD2R (at least 1 risk allele) CD patients, 4 NOD2NR (no risk alleles) CD patients, and 4 NOD2NR controls. Candidate genes selected by significance analysis of microarrays (SAM) were confirmed by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) assays of all the samples. Results: SAM detected upregulation of 18 genes in affected ileum in NOD2R compared to NOD2NR CD patients, including genes related to lymphocyte activation. SAM also detected altered ileal gene expression in unaffected NOD2NR ileal mucosal CD samples compared to NOD2NR control samples. qRT-PCR conducted on all the samples confirmed that increased CD3D expression in affected samples was associated with NOD2R status, and that increased MUC1, DUOX2, DMBT1 and decreased C4orf7 expression in unaffected samples was associated with CD, independent of NOD2 status. Conclusions: The results support the concept that NOD2 risk alleles contribute to impaired regulation of inflammation in the ileum. Furthermore, altered ileal gene expression, independent of NOD2 status, is detected in the unaffected proximal margin of resected ileum from CD patients. (Inflamm Bowel Dis 2010)

In Hinblick auf die Bedeutung der Proteinzufuhr wahrend korperlicher Aktivitat stehen Erhalt und Aufbau der Muskelmasse, Optimierung der Muskelkraft und Korperkomposition, Vermeidung einer katabolen Stoffwechsellage und Sicherstellung einer optimalen Regeneration in der Nachbelastungsphase im Mittelpunkt. Eine ausreichende und qualitativ hochwertige Proteinzufuhr stellt nicht nur das reine Ausgangssubstrat fur die de novo-Proteinsynthese dar, sondern induziert vielfaltige metabolische und hormonelle Stoffwechselprozesse. So stimulieren Proteine bzw. Aminosauren in unterschiedlicher Auspragung die Sekretion verschiedener Hormone wie Insulin, Wachstumshormon und Insulin like growth factor 1 (IGF-1). Es ist jedoch unbestritten, dass erst durch die Kombination von Training und Proteinzufuhr die optimale Basis fur eine gesteigerte muskulare Proteinbiosynthese in der Nachbelastungsphase geschaffen wird. Allerdings profitieren nicht nur Sportler von einer eiweisbetonten Ernahrung, sondern auch altere Personen sowie Patienten mit diabetischer Stoffwechsellage oder Gewichtsproblemen. Diese kann je nach Menge nicht nur zu einer Gewichtsreduktion und besseren Korperkomposition, sondern auch zur Erhohung der mitochondrialen Kapazitat und Verbesserung der Insulinsensitivitat sowie zum Erhalt der Muskelkraft und –funktion im hoheren Alter fuhren.

The discharge properties of hindlimb motoneurons in ketamine–xylazine anesthetized rats were measured to assess contributions of persistent intrinsic currents to these characteristics and to determine their distribution in motoneuron pools. Most motoneurons (30/37) responded to ramp current injections with adapting patterns of discharge and the frequency–current ( f– I) relations of nearly all motoneurons included a steep subprimary range of discharge. Despite the prevalence of adapting f– I relations, responses included indications that persistent inward currents (PICs) were activated, including increased membrane noise and prepotentials before discharge, as well as counterclockwise hysteresis and secondary ranges in f– I relations. Examination of spike thresholds and afterhyperpolarization (AHP) trajectories during repetitive discharge revealed systematic changes in threshold and trajectory within the subprimary, primary, and secondary f– I ranges. These changes in the primary and secondary ranges were qualitatively similar to those described previously for cat motoneurons. Within the subprimary range, AHP trajectories often included shallow approaches to threshold following recruitment and slope of the AHP ramp consistently increased until the subprimary range was reached. We suggest that PICs activated near recruitment contributed to these slope changes and formation of the subprimary range. Discharge characteristics were strongly correlated with motoneuron size, using input conductance as an indicator of size. Discharge adaptation, recruitment current, and frequency increased with input conductance, whereas both subprimary and primary f– I gains decreased. These results are discussed with respect to potential mechanisms and their functional implications.

The aspartate-rich macromolecules found at nucleation sites of calcifying organisms are widely implicated in regulating biomineral formation. Anecdotal evidence suggests that their ability to influence the onset of nucleation and composition of calcified structures may arise from effects on ion hydration. This study investigates the interactions of acidic amino acids and dipeptides with hydrated cations using molecular dynamics. By monitoring the hydration states of Mg2+, Ca2+, and Sr2+ during their approach to negatively charged molecules, we show that carboxylate moieties of Asp promote dehydration of Ca2+ and Sr2+. A contact ion pair (CIP) is not required to disrupt cation hydration, and we demonstrate that reductions and rearrangements of first shell water can begin at ion-Asp separation distances as large as approximately 4.9 A for Ca2+ and approximately 5.1 A for Sr2+. CIP formation between Ca2+ and Sr2+ and carboxylate groups decreases the total first shell coordination number from an average of 8.0 and 8.4 in bulk water to 7.5 and 8.0, respectively. The energy barrier to physically replacing waters about Ca2+ with carboxylate oxygen atoms is small (approximately 2 kcal/mol) as compared to a somewhat larger barrier for Sr2+ (approximately 4 kcal/mol). This may be explained by differences in the strength of Coulombic interactions between the cations and the Asp, resulting in different paths of approach toward Asp for Ca2+ and Sr2+. In contrast, the primary solvation shell of Mg2+ remains largely unchanged during interactions with Asp until the abrupt physical replacement of water by carboxylate oxygen atoms, which comes at a high energetic cost. These insights support the claim that carboxylated biomolecules increase the growth rate of calcite by lowering the energy barrier to Ca2+ dehydration. The findings also suggest a physical basis for the idea that ion-specific behaviors of Ca2+ and Mg2+ in cellular systems arise from a critical balance between water binding in the ion hydration shells versus their interactions with ligands present in intracellular environments.

Background: Persistent infection with high-risk types of human papillomavirus (HPV) is associated with cervical and other anogenital cancers. Purpose: This paper reports results of awareness of an HPV diagnosis and HPV knowledge from a multi-site study of HPV knowledge, attitudes and behavior, and the impact of an HPV diagnosis on women and their partners. Methods: During September 2003 - November 2005, a survey containing shared and site-specific items was administered to 736 women who had received HPV DNA testing in conjunction with cytology for cervical cancer screening. Results: Overall, there was low knowledge about HPV transmissibility, curability and the effects of an HPV diagnosis across all sites regardless of a woman's racial/ethnic and/or socio-demographic background. Further, only about 50% of the women were aware of their HPV diagnosis even after receiving their results and counseling from a health care professional. Discussion: There is need for consistent and clear information abou...

The law of diminishing returns, first described by economists to explain why, beyond a certain point, additional inputs produce smaller and smaller outputs, offers insight into many situations encountered in clinical medicine. For example, when the risk of an adverse event can be reduced in several different ways, the impact of each intervention can generally be shown mathematically to be reduced by the previous ones. The diminishing value of successive interventions is further reduced by adverse consequences (eg, drug-drug, drug-disease, and drug-nutrient interactions), as well as by the total expenditures of time, energy, and resources, which increase with each additional intervention. It is therefore important to try to prioritize interventions based on patient-centered goals and the relative impact and acceptability of the interventions. We believe that this has implications for clinical practice, research, and policy.

2) und arbeitet interdisziplinar mit qualifizierten Fachkraften aus den Bereichen Bewegung/Sport, Psychologie/Padagogik, Ernahrung und Medizin. Die korperliche Aktivitat steht mit 40praktischen Einheiten zwar im Fokus des einjahrigen Gruppenprogramms; Ernahrungsumstellung und Verhaltensanderung sind aber ebenso zentrale Themen der insgesamt 20 theoretischen Sitzungen. Aufgrund einer Rahmenvereinbarung zwischen M.O.B.I.L.I.S. und der Barmer GEK ist eine pauschalisierte Kostenerstattung des Programms moglich. Fur 2720Teilnehmer liegen Ergebnisse der Prozessevaluation vor. Diese belegen die Effizienz und Wirksamkeit des M.O.B.I.L.I.S.-Konzepts, das eine kostengunstige und nicht pharmakologische Therapieoption bei der Behandlung von adiposen Erwachsenen ist. Stichworte: Adipositas, Lebensstilintervention, Gewichtsreduktion, M.O.B.I.L.I.S.

When measuring recognition acuity in a research setting, the most widely used symbols are the Early Treatment of Diabetic Retinopathy Study (ETDRS) set of 10 Sloan letters. However, the symbols are not appropriate for patients unfamiliar with letters, and acuity for individual letters is variable. Alternative pictogram sets are available, but are generally comprised of fewer items. We set out to develop an open-access set of 10 pictograms that would elicit more consistent estimates of acuity across items than the ETDRS letters from visually normal adults. We measured monocular acuity for individual uncrowded optotypes within a newly designed set (The Auckland Optotype [TAO]), the ETDRS set, and Landolt Cs. Eleven visually normal adults were assessed on regular and vanishing formats of each set. Inter-optotype reliability and ability to detect subtle differences between participants were assessed using intraclass correlations (ICC) and fractional rank precision (FRP). The TAO vanishing set showed the strongest performance (ICC = 0.97, FRP = 0.90), followed by the other vanishing sets (Sloan ICC = 0.88, FRP = 0.74; Landolt ICC = 0.86, FRP = 0.80). Within the regular format, TAO again outperformed the existing sets (TAO ICC = 0.77, FRP = 0.75; Sloan ICC = 0.65, FRP = 0.64; Landolt ICC = 0.48, FRP = 0.63). For adults with normal visual acuity, the new optotypes (in both regular and vanishing formats) are more equally legible and sensitive to subtle individual differences than their Sloan counterparts. As this set does not require observers to be able to name Roman letters, and is freely available to use and modify, it may have wide application for measurement of acuity.

Cytokine and chemokine response profiles were studied in newborns, 10-yr-old children and post partum mothers. All study groups were repeatedly exposed to Entamoeba histolytica, Onchocerca volvulus and Plasmodium falciparum infections as indicated by their Immunoglobulin (IgG) responses to parasite-specific antigens. As key indicators for regulatory and pro-inflammatory cytokine and chemokine responses, Interferon (IFN)gamma and regulatory IL-10 were investigated, along with the chemokines MIP-1 alpha/CCL3, MIP-1 beta/CCL4, MDC/CCL22 and TARC/CCL17. Entamoeba histolytica antigens (EhAg) strongly activated pro-inflammatory MIP-1 alpha/CCL3 and MIP-1 beta/CCL4 responses of similar magnitude in mothers, children and neonates alike. Plasmodium falciparum antigens (PfAg) enhanced MIP-1 alpha/CCL3, MIP-1 beta/CCL4 and MDC/CCL22 production in neonates, but did not trigger these chemokines in mothers or 10-yr-old children. Onchocerca volvulus antigens (OvAg) activated IFN-gamma and TARC/CCL17 production in mothers but not in neonates and children. Crude IL-10 production [i.e., without subtracting spontaneous cellular release (baseline)] was highest in mothers and somewhat lower in neonates, while the lowest IL-10 amounts of all were released by peripheral blood mononuclear cells from 10-yr-old children. In summary, strong inflammatory chemokine responses to plasmodia and ameba antigens in newborns and 10-yr-old children suggest that adequately balanced immune regulatory mechanisms may not have developed yet in these age groups and that repeated exposure to parasite infections and immune maturation during childhood is required to generate similar cytokine and chemokine profiles as in adults.

Medical students encountering patients with unfamiliar, unconventional sexual practices may have attitudes that can affect open communication during sexual history-taking. We measured changes in first-year US medical student attitudes toward 22 non-traditional sexual behaviors before and after exposure to human sexuality instruction. An electronic, hand-held audience response system was used in a lecture hall to sample anonymous student attitudes toward this sensitive topic. Several attitudes were influenced by instruction, as shown by statistical comparisons before and after instruction. Students' attitudes shifted toward patterns favoring treatment for five out of 10 paraphilias that are not harmful of others. Most students favored imprisonment for pederasty before instruction, consistent with lessons about mandatory reporting of child sexual abuse, and this attitude increased non-significantly after instruction. Student attitudes were generally accepting of homosexuality, but were more accepting of fem...

The effect of polyparasite infections on cytokine and chemokine responses as well as the effect of antiparasite treatment was studied in children without parasite infection (the G0 group), in children singly infected with Schistosoma haematobium (the G1 group), and in children multiply infected with S. haematobium/Schistosoma mansoni, Entamoeba histolytica/Entamoeba dispar, and Necator americanus (the G3+ group). Linear regression analysis disclosed a significant risk for coinfection with hookworm and Schistosoma species. Polyparasite infections detected in 23% of children before treatment were present in 5% at 15 months after treatment. Chemokine responses to S. mansoni adult worm antigen (SmAg) diminished after treatment for macrophage inflammatory chemokine (MIP)-1alpha/chemokine (C-C motif) ligand (CCL)-3 (among G3+ children, by a factor of 200 [95% confidence interval {CI}, 33-1111]) and for MIP-1beta/CCL-4 (among G3+ children, by a factor of 26 [95% CI, 6-117]) but were enhanced for thymus- and activation-regulated chemokine/CCL-17 (among G3+ children, by a factor of 10 [95% CI, 3-32]) (P < .001 for all). In response to E. histolytica antigen, interleukin (IL)-13 levels increased after treatment among G1 children by a factor of 138 (95% CI, 12-1569) and among G3+ children by a factor of 21 (95% CI, 7-64) (P < .001 for both). Cellular production of interferon (IFN)-gamma in response to SmAg decreased 4 weeks after treatment among G3+ children, whereas T helper cell type 2 (Th2) IL-13 production was enhanced among G1 and G3+ children. In summary, polyparasite infections with S. haematobium/S. mansoni, E. histolytica/E. dispar, and N. americanus generated prominent proinflammatory cytokine and chemokine responses, and, after antihelminth treatment, the inflammatory chemokine response lessened as the Th2 responsiveness in coinfected children increased.