Clinical decision making by nurses when faced with third-space fluid shift. How well do they fare?

PubMed

Redden, M; Wotton, K

2001-01-01

Nurses' use of knowledge, the connection of this knowledge to treatment decisions and information actually used to reach such decisions, delineates nurses' level of expertise. Previous research has shown that nurses in their clinical decision-making use the hypothetico-deductive method and intuitive judgment or pattern recognition. This interpretive study explored experienced critical care nurses' (n = 5) and gastrointestinal surgical nurses' (n = 5) clinical decision-making processes through ascertaining their knowledge and understanding of third-space fluid shift in elderly patients undergoing major gastrointestinal surgery. Both groups of nurses, because of their experience with elderly patients undergoing gastrointestinal surgery, were assumed to be experts. Data collection techniques included semi-structured interviews and the use of think aloud protocol for clinical scenario analysis. The findings demonstrated that the gastrointestinal surgical nurses used the hypothetico-deductive method to recognize critical cues and the existence of a problem but could not name the problem. The critical care nurses, on the other hand, used a combination of the hypothetico-deductive method and pattern recognition as a basis for identification of critical cues. The critical care nurses also possessed in depth knowledge of third-space fluid shift and were able to use pivotal cues to identify the actual phenomenon. Ultimately, it would appear that the structure of critical care nurses' work, their increased educational qualifications and the culture of the critical care unit promote a more proactive approach to reasoning in the physiological domain. The findings have implications for the development of practice guidelines and curriculum development in both tertiary and continuing nurse education.

Special Education and the New Mental Health: A Response to New Direction of CCBD?

ERIC Educational Resources Information Center

Forness, Steven R.

2011-01-01

The emphasis or focus of a professional association often shifts imperceptibly over time in ways that neither its membership nor its leadership seems able to recognize until pivotal events compel it to do so. The historical shift from psychodynamic to behavioral approaches in special education for children with emotional or behavioral disorders…

Cinematic College: "National Lampoon's Animal House" Teaches Theories of Student Development

ERIC Educational Resources Information Center

Tucciarone, Krista M.

2007-01-01

The purpose of this qualitative study is to analyze how potential college-bound and current college students make meaning about the higher education experience from the legendary film that is pivotal in the American college culture, sets the trend for future college-themed films, and is a national phenomenon--"National Lampoon's Animal…

Blueberries and strawberries activate neuronal housekeeping in critical brain regions of stress-induced young rats

USDA-ARS?s Scientific Manuscript database

Dysfunctional autophagy, where accumulation of damaged or complex cellular components in neurons in response to sublethal cell stress has been implicated in an array of brain disorders. This phenomenon plays a pivotal role in aging, because of the increased vulnerability of the aging brain to incre...

Lateral femoral notch depth is not associated with increased rotatory instability in ACL-injured knees: a quantitative pivot shift analysis.

PubMed

Kanakamedala, Ajay C; Burnham, Jeremy M; Pfeiffer, Thomas R; Herbst, Elmar; Kowalczuk, Marcin; Popchak, Adam; Irrgang, James; Fu, Freddie H; Musahl, Volker

2018-05-01

A deep lateral femoral notch (LFN) on lateral radiographs is indicative of ACL injury. Prior studies have suggested that a deep LFN may also be a sign of persistent rotatory instability and a concomitant lateral meniscus tear. Therefore, the purpose of this study was to evaluate the relationship between LFN depth and both quantitative measures of rotatory knee instability and the incidence of lateral meniscus tears. It was hypothesized that greater LFN depth would be correlated with increased rotatory instability, quantified by lateral compartment translation and tibial acceleration during a quantitative pivot shift test, and incidence of lateral meniscus tears. ACL-injured patients enrolled in a prospective ACL registry from 2014 to 2016 were analyzed. To limit confounders, patients were only included if they had primary ACL tears, no concurrent ligamentous or bony injuries requiring operative treatment, and no previous knee injuries or surgeries to either knee. Eighty-four patients were included in the final analysis. A standardized quantitative pivot shift test was performed pre-operatively under anesthesia in both knees, and rotatory instability, specifically lateral compartment translation and tibial acceleration, was quantified using tablet image analysis software and accelerometer sensors. Standard lateral radiographs and sagittal magnetic resonance images (MRI) of the injured knee were evaluated for LFN depth. There were no significant correlations between LFN depth on either imaging modality and ipsilateral lateral compartment translation or tibial acceleration during a quantitative pivot shift test or side-to-side differences in these measurements. Patients with lateral meniscus tears were found to have significantly greater LFN depths than those without on conventional radiograph and MRI (1.0 vs. 0.6 mm, p < 0.05; 1.2 vs. 0.8 mm, p < 0.05, respectively). There was no correlation between lateral femoral notch depth on conventional radiographs or MRI and quantitative measures of rotatory instability. Concomitant lateral meniscus injury was associated with significantly greater LFN depth. Based on these findings, LFN depth should not be used as an indicator of excessive rotatory instability, but may be an indicator of lateral meniscus injury in ACL-injured patients. Prognostic level IV.

Plant responses, climate pivot points, and trade-offs in water-limited ecosystems

NASA Astrophysics Data System (ADS)

Munson, S. M.; Bunting, E.

2017-12-01

Ecosystem transitions and thresholds are conceptually well-defined and have become a framework to address vegetation response to climate change and land-use intensification, yet there are few approaches to define the environmental conditions which can lead to them. We demonstrate a novel climate pivot point approach using long-term monitoring data from a broad network of permanent plots, satellite imagery, and experimental treatments across the southwestern U.S. The climate pivot point identifies conditions that lead to decreased plant performance and serves as an early warning sign of increased vulnerability of crossing a threshold into an altered ecosystem state. Plant responses and climate pivot points aligned with the lifespan and structural characteristics of species, were modified by soil and landscape attributes of a site, and had non-linear dynamics in some cases. Species with strong increases in abundance when water was available were most susceptible to losses during water shortages, reinforcing plant energetic and physiological tradeoffs. Future research to uncover the heterogeneity of plant responses and climate pivot points at multiple scales can lead to greater understanding of shifts in ecosystem productivity and vulnerability to climate change.

Revision anterior cruciate ligament reconstruction with nonirradiated fresh-frozen patellar tendon allograft.

PubMed

Fox, Jeff A; Pierce, Mark; Bojchuk, John; Hayden, Jennifer; Bush-Joseph, Charles A; Bach, Bernard R

2004-10-01

To evaluate the effectiveness of a revision anterior cruciate ligament reconstruction with nonirradiated patellar tendon allograft used to salvage a failed index patellar tendon autograft procedure. Retrospective case series with minimum 2-year follow-up. Between 1993 and 1999, 39 patients underwent a revision reconstruction. Clinical, radiographic, arthrometric, and functional evaluations were performed. The Tegner, Lysholm, Noyes, Knee Injury and Osteoarthritis Outcome Score (KOOS), International Knee Documentation Committee (IKDC), and SF-12 rating scales were used. Statistical analysis was conducted with our Biostatistics Department. Thirty-two of 38 patients (84%) were personally evaluated. The mean patient age was 28 years (range, 16 to 57 years); the mean follow-up was 4.8 years (range, 2.1 to 12.1 years). After revision, there were significant improvements in the Lachman and pivot-shift test results: 87% had a grade 0/1+ Lachman and a 0/1+ pivot-shift. However, 25% had a grade 1+ pivot-shift. Postoperatively, KT-1000 testing revealed that 84% had a maximum manual side-to-side difference of < or =3 mm and 6% had >5 mm. Functional testing revealed a mean 4% difference in side-to-side comparisons for a single-leg hop for distance and time, as well as vertical jump. The mean results of Noyes sports function (72), Lysholm (75), Tegner (6.3), KOOS sports activity scale (67), SF-12 physical component (48), SF-12 mental component (55), and IKDC (71) were obtained. The Noyes sports activity score showed a significant improvement from 55 preoperatively to 70 at follow-up. Subjectively, 87% of patients indicated that they were completely or mostly satisfied with the surgical outcome. One patient required another revision. The 2- to 11-year follow-up showed that the results of revision ACL reconstruction with a nonirradiated patellar tendon allograft were less favorable than those of a primary anterior cruciate ligament reconstruction, with a lower subjective satisfaction level and a higher percentage of patients with grade 1+ or higher pivot-shift results. However, when compared with previously published reports, our results were comparable and underscore that revision anterior cruciate ligament surgery should be approached with tempered enthusiasm and careful preoperative counseling, and considered as a salvage procedure. Level IV.

Exploring the response shift phenomenon in childhood patients with cancer and its effect on health-related quality of life.

PubMed

Brinksma, Aeltsje; Tissing, Wim J E; Sulkers, Esther; Kamps, Willem A; Roodbol, Petrie F; Sanderman, Robbert

2014-01-01

To explore the response shift phenomenon in pediatric patients with cancer and to determine its effects on ratings of health-related quality of life (HRQOL). Retrospective pre- and post-test design. Pediatric oncology department in the northern part of the Netherlands. 37 children newly diagnosed with cancer and 80 parents. The then-test method was used to determine response shift. HRQOL was assessed within two weeks postdiagnosis (pretest) and three months later (post-test) using both child and parent reports of PedsQL and Cantril's ladder. The post-test and then-test were administered concurrently. Overall and multidimensional HRQOL. Scores on Cantril's then-test were lower than the pretest in both child and parent reports, indicating response shift in the assessment of overall HRQOL. Children experienced a greater response shift than parents. No differences were found between the PedsQL then- and pretests. Both child- and parent-report ratings of overall HRQOL were affected by response shift, resulting in an underestimation of the improvement in overall HRQOL between diagnosis and three months postdiagnosis. No response shift was demonstrated in the more specific domains of HRQOL (PedsQL). Knowledge of the response shift phenomenon helps nurses to better interpret the outcomes of HRQOL. The use of the PedsQL instrument is recommended in future studies that aim to demonstrate changes in HRQOL.

The anterolateral ligament (ALL) and its role in rotational extra-articular stability of the knee joint: a review of anatomy and surgical concepts.

PubMed

Roessler, Philip P; Schüttler, Karl F; Heyse, Thomas J; Wirtz, Dieter C; Efe, Turgay

2016-03-01

The anterolateral ligament of the knee (ALL) has caused a lot of rumors in orthopaedics these days. The structure that was first described by Segond back in 1879 has experienced a long history of anatomic descriptions and speculations until its rediscovery by Claes in 2013. Its biomechanical properties and function have been examined recently, but are not yet fully understood. While the structure seems to act as a limiter of internal rotation and lateral meniscal extrusion its possible proprioceptive effect remains questionable. Its contribution to the pivot shift phenomenon has been uncovered in parts, therefore it has been recognized that a concomitant anterolateral stabilization together with ACL reconstruction may aid in prevention of postoperative instability after severe ligamentous knee damages. However, there are a lot of different methods to perform this procedure and the clinical outcome has yet to be examined. This concise review will give an overview on the present literature to outline the long history of the ALL under its different names, its anatomic variances and topography as well as on histologic examinations, imaging modalities, arthroscopic aspects and methods for a possible anterolateral stabilization of the knee joint.

Tropical grasslands: A pivotal place for a more multi-functional agriculture.

PubMed

Boval, Maryline; Angeon, Valérie; Rudel, Tom

2017-02-01

Tropical grasslands represent a pivotal arena for the sustainable intensification of agriculture in the coming decades. The abundant ecosystem services provided by the grasslands, coupled with the aversion to further forest destruction, makes sustainable intensification of tropical grasslands a high policy priority. In this article, we provide an inventory of agricultural initiatives that would contribute to the sustainable intensification of the tropical grassland agro-ecosystem, and we recommend a shift in the scientific priorities of animal scientists that would contribute to realization of a more agro-ecological and multi-functional agriculture in the world's tropical grasslands.

"Daddy, Where Did the Words Go?" How Teachers Can Help Emergent Readers Develop a Concept of Word in Text

ERIC Educational Resources Information Center

Flanigan, Kevin

2006-01-01

This article focuses on a concept that has rarely been studied in beginning reading research--a child's concept of word in text. Recent examinations of this phenomenon suggest that a child's ability to match spoken words to written words while reading--a concept of word in text--plays a pivotal role in early reading development. In this article,…

Double-bundle ACL reconstruction can improve rotational stability.

PubMed

Yagi, Masayoshi; Kuroda, Ryosuke; Nagamune, Kouki; Yoshiya, Shinichi; Kurosaka, Masahiro

2007-01-01

Double-bundle anterior cruciate ligament (ACL) reconstruction reproduces anteromedial and posterolateral bundles, and thus has theoretical advantages over conventional single-bundle reconstruction in controlling rotational torque in vitro. However, its superiority in clinical practice has not been proven. We analyzed rotational stability with three reconstruction techniques in 60 consecutive patients who were randomly divided into three groups (double-bundle, anteromedial single-bundle, posterolateral single-bundle). In the reconstructive procedure, the hamstring tendon was harvested and used as a free tendon graft. Followup examinations were performed 1 year after surgery. Anteroposterior laxity of the knee was examined with a KT-1000 arthrometer, whereas rotatory instability, as elicited by the pivot shift test, was assessed using a new measurement system incorporating three-dimensional electromagnetic sensors. Routine clinical evaluations, including KT examination, demonstrated no differences among the three groups. However, using the new measurement system, patients with double-bundle ACL reconstruction showed better pivot shift control of complex instability than patients with anteromedial and posterolateral single-bundle reconstruction.

The carbon balance pivot point of southwestern U.S. semiarid ecosystems: Insights from the 21st century drought

NASA Astrophysics Data System (ADS)

Scott, Russell L.; Biederman, Joel A.; Hamerlynck, Erik P.; Barron-Gafford, Greg A.

2015-12-01

Global-scale studies indicate that semiarid regions strongly regulate the terrestrial carbon sink. However, we lack understanding of how climatic shifts, such as decadal drought, impact carbon sequestration across the wide range of structural diversity in semiarid ecosystems. Therefore, we used eddy covariance measurements to quantify how net ecosystem production of carbon dioxide (NEP) differed with relative grass and woody plant abundance over the last decade of drought in four Southwest U.S. ecosystems. We identified a precipitation "pivot point" in the carbon balance for each ecosystem where annual NEP switched from negative to positive. Ecosystems with grass had pivot points closer to the drought period precipitation than the predrought average, making them more likely to be carbon sinks (and a grass-free shrubland, a carbon source) during the current drought. One reason for this is that the grassland located closest to the shrubland supported higher leaf area and photosynthesis at the same water availability. Higher leaf area was associated with a greater proportion of evapotranspiration being transpiration (T/ET), and therefore with higher ecosystem water use efficiency (gross ecosystem photosynthesis/ET). Our findings strongly show that water availability is a primary driver of both gross and net semiarid productivity and illustrate that structural differences may contribute to the speed at which ecosystem carbon cycling adjusts to climatic shifts.

The Influence of Meniscal and Anterolateral Capsular Injury on Knee Laxity in Patients With Anterior Cruciate Ligament Injuries.

PubMed

Musahl, Volker; Rahnemai-Azar, Ata A; Costello, Joanna; Arner, Justin W; Fu, Freddie H; Hoshino, Yuichi; Lopomo, Nicola; Samuelsson, Kristian; Irrgang, James J

2016-12-01

The role of the anterolateral capsule (ALC) as a secondary restraint to quantitative rotatory laxity of patients with an anterior cruciate ligament (ACL) injury is currently debated. The purpose was to determine the influence of concomitant ALC injuries as well as injuries to other soft tissue structures on rotatory knee laxity in patients with an ACL injury. It was hypothesized that a concomitant ALC injury would be associated with increased rotatory knee laxity as measured during a quantitative pivot-shift test. Cross-sectional study; Level of evidence, 3. Forty-one patients with an ACL injury (average age, 23 ± 6.9 years) were enrolled. Two blinded musculoskeletal radiologists reviewed magnetic resonance imaging (MRI) scans for the presence of ACL injuries and concomitant soft tissue injuries including the ALC, medial collateral ligament, lateral collateral ligament, posterolateral corner, medial meniscus, and lateral meniscus. A standardized pivot-shift test was performed under anesthesia, and rotatory laxity was quantified according to anterior translation of the lateral tibial compartment during the pivot-shift maneuver. The Student t test was used to analyze the data. Statistical significance was set at P < .05. A complete ACL rupture was confirmed in all of the patients. MRI evidence of an ALC injury was observed in 21 (51%) of the patients. Patients with MRI evidence of an ALC injury had significantly higher rotatory knee laxity (3.6 ± 1.5 mm) compared with those without an ALC injury (2.7 ± 1.5 mm; P = .04). Lateral and medial meniscus injuries were detected in 17 (41%) and 19 (46%) patients, respectively. Patients with MRI evidence of either a medial meniscus injury or lateral meniscus injury had significantly higher rotatory knee laxity compared with patients without these injuries (medial meniscus: 3.7 ± 1.4 mm vs 2.7 ± 1.6 mm, respectively; lateral meniscus: 3.7 ± 1.7 mm vs 2.7 ± 1.3 mm, respectively) (P = .03 for both). MRI evidence of a concomitant injury to the ALC, medial meniscus, or lateral meniscus is associated with increased knee rotatory laxity in patients with an ACL injury. These structures may function as important secondary stabilizers in an ACL-injured knee. Careful assessment and proper treatment of injuries to these secondary stabilizers should be considered, especially in knees with a high level of the pivot shift. © 2016 The Author(s).

E-health: how to make the right choice.

PubMed

Perez, Elizabeth

2009-01-01

TOPIC. The online health promotion phenomenon is a pivotal movement toward consumer empowerment. The challenges for the 21st century are to create meaningful, accurate online health communication interventions that successfully change behavior and improve health. PURPOSE. The Internet is a valuable tool for health promotion, self-care tools, and decision aids components for a high-quality care. The nurse educator ensures e-health sites used meet the criteria for achieving optimal wellness for the consumer. SOURCES. Published literature. CONCLUSIONS. It is crucial for nurses to use reputable e-health sites for consumer engagement and education. Researchers and practitioners are exploring the phenomenon of e-health to gain a better understanding of how to engage these consumers in health behavioral change programs.

Districts Gear up for Shift to Informational Texts

ERIC Educational Resources Information Center

Gewertz, Catherine

2012-01-01

The Common Core State Standards' emphasis on informational text arose in part from research suggesting that employers and college instructors found students weak at comprehending technical manuals, scientific and historical journals, and other texts pivotal to work in those arenas. The common core's vision of informational text includes literary…

Bloch-Siegert shift in Dirac-Weyl fermionic systems

NASA Astrophysics Data System (ADS)

Kumar, Upendra; Kumar, Vipin; Enamullah, Setlur, Girish S.

2018-04-01

The Bloch-Siegert shift is a phenomenon in quantum optics, typically seen in two-level systems, when the driving field is sufficiently strong. The inclusion of frequency doubling effect (counter rotating term) in the conventional rotating wave approximation (RWA) changes the resonance condition thereby producing a rather small shift in the resonance condition, which is known as the Bloch-Siegert shift (BSS). Rabi oscillations in Dirac-Weyl fermionic systems exhibit anomalous behavior far from resonance, called anomalous Rabi oscillations. Therefore, in the present work, we study the phenomenon of the Bloch-Siegert shift in Weyl semimetal and topological insulator (TI) far from resonance, called anomalous Bloch-Siegert shift (ABSS). It is seen that the change in the resonance condition of anomalous Rabi oscillations is drastic in Weyl semimetal and TI. The ABSS in Weyl semimetals is highly anisotropic, whereas it is isotropic in TI. In case of TI, it is the Chern number which plays a crucial role to produce substantial change in the ABSS.

Investigation of an anomalous hump phenomenon in via-type amorphous In-Ga-Zn-O thin-film transistors under positive bias temperature stress

NASA Astrophysics Data System (ADS)

Yang, Jianwen; Liao, Po-Yung; Chang, Ting-Chang; Chen, Bo-Wei; Huang, Hui-Chun; Su, Wan-Ching; Chiang, Hsiao-Cheng; Zhang, Qun

2017-04-01

Amorphous InGaZnO thin film transistors (a-IGZO TFTs) with an etching-stop layer (ESL) exhibit an anomalous negative shift of threshold voltage (Vth) under positive bias temperature stress. TFTs with wider and shorter channels show a clear hump phenomenon, resulting from the existence of both main channels and parasitic channels. The electrons trapped in the gate insulator are responsible for the positive shift in the main channel characteristics. The electrons trapped near the IGZO edges and the holes injected into the ESL layer above InGaZnO (IGZO) jointly determine the shift of the parasitic TFT performance.

The carbon balance pivot point of southwestern U.S. semiarid ecosystems: Insights from the 21st century drought

USDA-ARS?s Scientific Manuscript database

Global-scale studies indicate that semiarid regions strongly regulate the terrestrial carbon sink. However, we lack understanding of how climatic shifts, such as decadal drought, impact carbon sequestration across the wide-range of structural diversity in semiarid ecosystems. Therefore, we used edd...

Three-Dimensional Instruction: Using a New Type of Teaching in the Science Classroom

ERIC Educational Resources Information Center

Krajcik, Joe

2015-01-01

Science teaching and learning in the United States are at a pivotal point. "A Framework for K-12 Science Education" (NRC 2012b) and the "Next Generation Science Standards" ("NGSS"; NGSS Lead States 2013) shift science educators' focus from simply teaching science ideas to helping students figure out phenomena and…

Comparative evaluation of the results of three techniques in the reconstruction of the anterior cruciate ligament, with a minimum follow-up of two years.

PubMed

Cury, Ricardo de Paula Leite; Sprey, Jan Willem Cerf; Bragatto, André Luiz Lima; Mansano, Marcelo Valentim; Moscovici, Herman Fabian; Guglielmetti, Luiz Gabriel Betoni

2017-01-01

To compare the clinical results of the reconstruction of the anterior cruciate ligament by transtibial, transportal, and outside-in techniques. This was a retrospective study on 90 patients (ACL reconstruction with autologous flexor tendons) operated between August 2009 and June 2012, by the medial transportal (30), transtibial (30), and "outside-in" (30) techniques. The following parameters were assessed: objective and subjective IKDC, Lysholm, KT1000, Lachman test, Pivot-Shift and anterior drawer test. On physical examination, the Lachman test and Pivot-Shift indicated a slight superiority of the outside-in technique, but without statistical significance ( p  = 0.132 and p  = 0.186 respectively). The anterior drawer, KT1000, subjective IKDC, Lysholm, and objective IKDC tests showed similar results in the groups studied. A higher number of complications were observed in the medial transportal technique ( p  = 0.033). There were no statistically significant differences in the clinical results of patients undergoing reconstruction of the anterior cruciate ligament by transtibial, medial transportal, and outside-in techniques.

Efficacy of knee joint aspiration in patients with acute ACL injury in the emergency department.

PubMed

Wang, Joon Ho; Lee, Jin Hyuck; Cho, Youngsuk; Shin, Jung Min; Lee, Byung Hoon

2016-08-01

To evaluate the influence of joint aspiration on the sensitivity of physical examination for diagnosing acute anterior cruciate ligament (ACL) lesion in the second outpatient-department (OPD) follow-up referred from emergency department (ED). This retrospective study included sixty patients underwent ACL reconstruction with initial visit at ED. They were divided into two groups based on the presence or absence of joint aspiration at ED. All participants were referred to second OPD follow-up within 7-14days after the injury. Clinical manifestation (including visual analogue scale (VAS) for pain, range of motion (ROM), and severity of knee effusion) and physical examination (Lachman test and pivot shift test) were checked in ED and the second OPD follow-up. The group of patients with joint aspiration (G1) showed substantial decreases in mean values of VAS for pain (p=0.005), ROM (p=0.001), and effusion level (p<0.001), even higher VAS and effusion level and lower ROM at the initial visit of ED than the other group (G2). The sensitivity of positive Lachman and pivot shift test was significantly (p<0.05) increased following knee joint aspiration. Positive Lachman test was recorded at 76.5% in the second follow-up in G1, which was significantly (p=0.047) higher than that (47.6%) in G2. The percentage of positive pivot shift test was recorded at 76.5% in the second follow-up in G1, which as significantly (p<0.001) higher than that (31.0%) in G2. Knee joint aspiration in acute ACL injury with suspected hemarthrosis could be considered as a diagnostic procedure. Joint aspiration in early medical attendance might be able to lower pain scores or raise the sensitivity of physical examination for diagnosing acute ACL injury at follow up visit in orthopedic outpatient department. Retrospective cohort study III. Copyright © 2016 Elsevier Ltd. All rights reserved.

Revision anterior cruciate ligament reconstruction by double-bundle technique using multi-strand semitendinosus tendon.

PubMed

Muneta, Takeshi; Hara, Kenji; Ju, Young-Jin; Mochizuki, Tomoyuki; Morito, Toshiyuki; Yagishita, Kazuyoshi; Sekiya, Ichiro

2010-06-01

The purpose of the study was to compare the outcome of revision anterior cruciate ligament (ACL) reconstruction by the double-bundle (DB) technique using multi-strand semitendinosus tendon with that of primary reconstruction by use of the same technique. The study included 21 patients who underwent revision ACL reconstruction (mean follow-up, 40 months) with the semitendinosus tendon DB technique between 1995 and 2006 and 86 unilateral primary DB ACL reconstructions (mean follow-up, 33 months) between 2000 and 2004. The outcome of both groups was compared based on differences between operated and unoperated limbs and modified International Knee Documentation Committee grades. Both the overall and sports-related subjective scores were evaluated between the 2 groups. The KT measurements (MEDmetric, San Diego, CA) averaged 1.7 mm (SD, 1.8 mm) in the revision group and 1.5 mm (SD, 1.6 mm) in the primary group. There was no significant difference in KT measurements between the 2 groups. The Lachman test was negative in 83% of revision cases and 87% of primary cases; the anterior drawer test was negative in 83% and 91%, respectively, and the pivot-shift test was negative in 78% and 90%, respectively. There was a tendency for a positive pivot-shift test in the revision group being higher. The Lysholm score and subjective recovery score were significantly lower in the revision group. The semitendinosus tendon DB revision procedure provided range of motion and anterior stability comparable to those after primary DB surgery and a comparable return to athletic activities. However, the patients tended to have positive pivot-shift test results. The revision cases were also inferior in terms of the general evaluation of recovery of knee condition. The outcome scores were lower overall in the revision group. Level IV, therapeutic case series. Copyright (c) 2010 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Ratiometric imaging of gastrodermal lipid bodies in coral-dinoflagellate endosymbiosis

NASA Astrophysics Data System (ADS)

Luo, Y.-J.; Wang, L.-H.; Chen, W.-N. U.; Peng, S.-E.; Tzen, J. T.-C.; Hsiao, Y.-Y.; Huang, H.-J.; Fang, L.-S.; Chen, C.-S.

2009-03-01

Cnidaria-dinoflagellate endosymbiosis is the phenomenon of autotrophic symbionts living inside the gastrodermal cells of their animal hosts. The molecular mechanism that regulates this association remains unclear. Using quantitative microscopy, we now provide evidence that the dynamic lipid changes in gastrodermal “lipid bodies” (LBs) reflect the symbiotic status of the host cell and its symbiont in the hermatypic coral Euphyllia glabrescens. By dual-emission ratiometric imaging with a solvatochromic fluorescent probe, Nile red (9-diethylamino-5H-benzo[α]phenoxazine-5-one), we showed that the in situ distribution of polar versus neutral lipids in LBs in living gastrodermal cells and symbionts can be analyzed. The ratio of Nile red fluorescence at red (R) versus green (G) wavelength region (i.e., R/G ratio) correlated with the relative molar ratio of polar (P) versus neutral (NP) lipids (i.e., P/NP ratio). The R/G ratio in host LBs increased after bleaching, indicating a decrease in neutral lipid accumulation in gastrodermal cells. On the other hand, neutral lipid accumulation inside the symbiont LBs resulted in gradual decreases of the R/G ratio as a result of bleaching. In comparison with the bleaching event, there was no relative lipid concentration change in host LBs under continual light or dark treatments as shown by insignificant R/G ratio shift. Patterns of R/G ratio shift in symbiont LBs were also different between corals undergoing bleaching and continual light/dark treatment. In the latter, there was little lipid accumulation in symbionts, with no resulting R/G ratio decrease. These results, demonstrating that the symbiotic status positively correlated with morphological and compositional changes of lipid bodies, not only highlight the pivotal role of LBs, but also implicate an involvement of lipid trafficking in regulating the endosymbiosis.

Shift Work and Sleep: Medical Implications and Management

PubMed Central

Jehan, Shazia; Zizi, Ferdinand; Pandi-Perumal, Seithikurippu R; Myers, Alyson K; Auguste, Evan; Jean-Louis, Girardin; McFarlane, Samy I

2018-01-01

The primary occupation of a worker can play an important role in achieving good sleep, as well as good physical and mental health. Shift Work Sleep Disorder (SWSD) is a condition that results from working atypical shifts (i.e. other than the typical 9 am to 5 pm schedule). Individuals who manifest SWSD usually complaint of trouble sleeping, excessive sleepiness and fatigue which interfere with overall functioning. Misalignment of circadian timing system results in undesirable health consequences. Among shift workers, good sleep is essential for efficient functioning. Disturbed sleep is associated with anxiety, depression, poor physical and mental health and eventually, leads to impaired quality of life. The economic burden of undiagnosed, under-and untreated shift work is high. The healthcare workers and policymakers can play a pivotal role in dealing with this issue by educating the public and providing them with adequate privileges to perform their work. PMID:29517053

Dynamic evaluation of pivot-shift kinematics in physeal-sparing pediatric anterior cruciate ligament reconstruction techniques.

PubMed

Sena, Mark; Chen, James; Dellamaggioria, Ryan; Coughlin, Dezba G; Lotz, Jeffrey C; Feeley, Brian T

2013-04-01

Conventional transphyseal anterior cruciate ligament (ACL) reconstruction techniques in skeletally immature patients have been questioned because of potential physeal injuries. Consequently, multiple alternative reconstruction options have been described to restore stability while sparing the physes in the skeletally immature patient. All pediatric reconstruction techniques will restore knee stability to intact levels, and the knee stability index (KSI) will discriminate stability patterns between reconstruction techniques. Controlled laboratory study. A novel mechanical pivot-shift device (MPSD) that consistently applies dynamic loads to cadaveric knees was used to study the effect of different physeal-sparing ACL reconstruction techniques on knee stability. Six adult cadaveric fresh-frozen knees were used. All knees were tested with 3 physeal-sparing reconstruction techniques: all epiphyseal (AE), transtibial over the top (TT), and iliotibial band (ITB). The MPSD was used to consistently perform a simulated pivot-shift maneuver. Tibial anterior displacement (AD), internal rotation (IR), posterior translational velocity (PTV), and external rotational velocity (ERV) were recorded using an Optotrak navigation system. The KSI (score range, 0-100; 0 = intact knee) was quantified using a regression analysis of AD, IR, PTV, and ERV. Repeated-measures analysis of variance and logistic regression were used for comparison of kinematics and derivation of KSI coefficients, respectively. ACL deficiency resulted in an increase of 20% to 115% in all primary stability measures tested compared with the ACL-intact state. All reconstructions resulted in a decrease in ADmax and IRmax as well as PTVmax and ERVmax to within intact ranges, indicating that all reconstructions do improve stability compared with the ACL-deficient state. The ITB reconstruction overconstrained AD and IR by 38% and 52%, respectively. The mean (±SD) KSI for the ACL-deficient state was 61.7 ± 22.2 (range, 47-100), while the ITB reconstruction had a mean KSI of 0.82 ± 24.0 (range, -24 to 35), the TT reconstruction had a mean KSI of 13.3 ± 8.9 (range, 0.3-23), and the AE reconstruction had a mean KSI of -4.0 ± 15.2 (range, -24 to 14). The KSI was not significantly different between reconstructions, and all were significantly lower than the ACL-deficient state (P < .0001). Although all reconstruction techniques tested were able to partially stabilize an ACL-deficient knee, the AE reconstruction was most effective in restoring native knee kinematics under dynamic loading conditions that mimic the pivot-shift test. This study provides orthopaedic surgeons with objective dynamic rotational data on the ability of physeal-sparing ACL reconstructions to better determine the ideal technique for ACL construction in skeletally immature patients.

An In Vitro Robotic Assessment of the Anterolateral Ligament, Part 2: Anterolateral Ligament Reconstruction Combined With Anterior Cruciate Ligament Reconstruction.

PubMed

Nitri, Marco; Rasmussen, Matthew T; Williams, Brady T; Moulton, Samuel G; Cruz, Raphael Serra; Dornan, Grant J; Goldsmith, Mary T; LaPrade, Robert F

2016-03-01

Recent biomechanical studies have demonstrated that an extra-articular lateral knee structure, most recently referred to as the anterolateral ligament (ALL), contributes to overall rotational stability of the knee. However, the effect of anatomic ALL reconstruction (ALLR) in the setting of anterior cruciate ligament (ACL) reconstruction (ACLR) has not been biomechanically investigated or validated. The purpose of this study was to investigate the biomechanical function of anatomic ALLR in the setting of a combined ACL and ALL injury. More specifically, this investigation focused on the effect of ALLR on resultant rotatory stability when performed in combination with concomitant ACLR. It was hypothesized that ALLR would significantly reduce internal rotation and axial plane translation laxity during a simulated pivot-shift test compared with isolated ACLR. Controlled laboratory study. Ten fresh-frozen cadaveric knees were evaluated with a 6 degrees of freedom robotic system. Knee kinematics were evaluated with simulated clinical examinations including a simulated pivot-shift test consisting of coupled 10-N·m valgus and 5-N·m internal rotation torques, a 5-N·m internal rotation torque, and an 88-N anterior tibial load. Kinematic differences between ACLR with an intact ALL, ACLR with ALLR, and ACLR with a deficient ALL were compared with the intact state. Single-bundle ACLR tunnels and ALLR tunnels were placed anatomically according to previous quantitative anatomic attachment descriptions. Combined anatomic ALLR and ACLR significantly improved the rotatory stability of the knee compared with isolated ACLR in the face of a concurrent ALL deficiency. During a simulated pivot-shift test, ALLR significantly reduced internal rotation and axial plane tibial translation when compared with ACLR with an ALL deficiency. Isolated ACLR for the treatment of a combined ACL and ALL injury was not able to restore stability of the knee, resulting in a significant increase in residual internal rotation laxity. ALLR did not affect anterior tibial translation; no significant differences were observed between the varying ALL conditions with ACLR except between ACLR with an intact ALL and ACLR with a deficient ALL at 0° of flexion. In the face of a combined ACL and ALL deficiency, concurrent ACLR and ALLR significantly improved the rotatory stability of the knee compared with solely reconstructing the ACL. Significant increases in residual internal rotation and laxity during the pivot-shift test may exist in both acute and chronic settings of an ACL deficiency and in patients treated with isolated ACLR for a combined ACL and ALL deficiency. For this subset of patients, surgical treatment of the ALL, in addition to ACLR, should be considered to restore knee stability. © 2016 The Author(s).

Spectral evolution with incremental nanocoating of long period fiber gratings

NASA Astrophysics Data System (ADS)

Del Villar, Ignacio; Corres, Jesus M.; Achaerandio, Miguel; Arregui, Francisco J.; Matias, Ignacio R.

2006-12-01

The incremental deposition of a thin overlay on the cladding of a long-period fiber grating (LPFG) induces important resonance wavelength shifts in the transmission spectrum. The phenomenon is proved theoretically with a vectorial method based on hybrid modes and coupled mode theory, and experimentally with electrostatic self-assembly monolayer process. The phenomenon is repeated periodically for specific overlay thickness values with the particularity that the shape of the resonance wavelength shift depends on the thickness of the overlay. The main applications are the design of wide optical filters and multiparameter sensing devices.

Preventing Fusion Mass Shift Avoids Postoperative Distal Curve Adding-on in Adolescent Idiopathic Scoliosis.

PubMed

Shigematsu, Hideki; Cheung, Jason Pui Yin; Bruzzone, Mauro; Matsumori, Hiroaki; Mak, Kin-Cheung; Samartzis, Dino; Luk, Keith Dip Kei

2017-05-01

Surgery for adolescent idiopathic scoliosis (AIS) is only complete after achieving fusion to maintain the correction obtained intraoperatively. The instrumented or fused segments can be referred to as the "fusion mass". In patients with AIS, the ideal fusion mass strategy has been established based on fulcrum-bending radiographs for main thoracic curves. Ideally, the fusion mass should achieve parallel endplates of the upper and lower instrumented vertebra and correct any "shift" for truncal balance. Distal adding-on is an important element to consider in AIS surgery. This phenomenon represents a progressive increase in the number of vertebrae included distally in the primary curvature and it should be avoided as it is associated with unsatisfactory cosmesis and an increased risk of revision surgery. However, it remains unknown whether any fusion mass shift, or shift in the fusion mass or instrumented segments, affects global spinal balance and distal adding-on after curve correction surgery in patients with AIS. (1) To investigate the relationship among postoperative fusion mass shift, global balance, and distal adding-on phenomenon in patients with AIS; and (2) to identify a cutoff value of fusion mass shift that will lead to distal adding-on. This was a retrospective study of patients with AIS from a single institution. Between 2006 and 2011 we performed 69 selective thoracic fusions for patients with main thoracic AIS. All patients were evaluated preoperatively and at 2 years postoperatively. The Cobb angle between the cranial and caudal endplates of the fusion mass and the coronal shift between them, which was defined as "fusion mass shift", were measured. Patients with a fusion mass Cobb angle greater than 20° were excluded to specifically determine the effect of fusion mass shift on distal adding-on phenomenon. Fusion mass shift was empirically set as 20 mm for analysis. Therefore, of the 69 patients who underwent selective thoracic fusion, only 52 with a fusion mass Cobb angle of 20° or less were recruited for study. We defined patients with a fusion mass shift of 20 mm or less as the balanced group and those with a fusion mass shift greater than 20 mm as the unbalanced group. A receiver operating characteristic (ROC) curve was used to determine the cutoff point of fusion mass shift for adding-on. Of the 52 patients studied, fusion mass shift (> 20 mm) was noted in 11 (21%), and six of those patients had distal adding-on at final followup. Although global spinal balance did not differ significantly between patients with or without fusion mass shift, the occurrence of adding-on phenomenon was significantly higher in the unbalanced group (55% (six of 11 patients), odds ratio [OR], 8.6; 95% CI, 2-39; p < 0.002) than the balanced group (12% [five of 41 patients]). Based on the ROC curve analysis, a fusion mass shift more than 18 mm was observed as the cutoff point for distal adding-on phenomenon (area under the curve, 0.70; 95% CI, 0.5-0.9; likelihood ratio, 5.0; sensitivity, 0.64; specificity, 0.73; positive predictive value, 39% [seven of 18 patients]; negative predictive value, 88% [30 of 34 patients]; OR, 4.8; 95% CI, 1-20; p = 0.02). Our study illustrates the substantial utility of the fulcrum-bending radiograph in determining fusion levels that can avoid fusion mass shift; thereby, underlining its importance in designing personalized surgical strategies for patients with scoliosis. Preoperatively, determining fusion levels by fulcrum-bending radiographs to avoid residual fusion mass shift is imperative. Intraoperatively, any fusion mass shift should be corrected to avoid distal adding-on, reoperation, and elevated healthcare costs. Level II, prognostic study.

Choice Shift in Opinion Network Dynamics

NASA Astrophysics Data System (ADS)

Gabbay, Michael

Choice shift is a phenomenon associated with small group dynamics whereby group discussion causes group members to shift their opinions in a more extreme direction so that the mean post-discussion opinion exceeds the mean pre-discussion opinion. Also known as group polarization, choice shift is a robust experimental phenomenon and has been well-studied within social psychology. In opinion network models, shifts toward extremism are typically produced by the presence of stubborn agents at the extremes of the opinion axis, whose opinions are much more resistant to change than moderate agents. However, we present a model in which choice shift can arise without the assumption of stubborn agents; the model evolves member opinions and uncertainties using coupled nonlinear differential equations. In addition, we briefly describe the results of a recent experiment conducted involving online group discussion concerning the outcome of National Football League games are described. The model predictions concerning the effects of network structure, disagreement level, and team choice (favorite or underdog) are in accord with the experimental results. This research was funded by the Office of Naval Research and the Defense Threat Reduction Agency.

Casting a Statewide Strategic Performance Net: Interlaced Data and Responsive Supports

ERIC Educational Resources Information Center

Layland, Allison; Redding, Sam

2017-01-01

The pivot point for educational change is now firmly placed with the district, rebalancing the position of the state and the school relative to the local education agency (LEA). The state education agency (SEA) has been shifting its emphasis for decades, from a compliance-focused authority to a change agent equipped with systems, processes,…

Two Versions of "Common" Test Eyed

ERIC Educational Resources Information Center

Gewertz, Catherine

2012-01-01

An unprecedented assessment project involving half the states is planning a significant shift: Instead of designing one test for all of them, it will offer a choice of a longer and a shorter version. The pivot came in response to some states' resistance to spending more time and money on testing for the common standards. The plan under discussion…

Snout allometry in seahorses: insights on optimisation of pivot feeding performance during ontogeny.

PubMed

Roos, Gert; Van Wassenbergh, Sam; Herrel, Anthony; Adriaens, Dominique; Aerts, Peter

2010-07-01

As juvenile life-history stages are subjected to strong selection, these stages often show levels of performance approaching those of adults, or show a disproportionately rapid increase of performance with age. Although testing performance capacity in aquatic suction feeders is often problematic, in pivot feeders such as seahorses models have been proposed to estimate whether snout length is optimal to minimise the time needed to reach the prey. Here, we investigate whether the same model can also explain the snout lengths in an ontogenetic series of seahorses, explore how pivot feeding kinematics change during ontogeny, and test whether juveniles show disproportionate levels of performance. Our analysis shows that the dimensions of the snout change during ontogeny from short and broad to long and narrow. Model calculations show that the snout lengths of newborn and juvenile seahorses are nearly optimal for minimising prey reach time. However, in juveniles the centre of head rotation in the earth-bound frame of reference is located near the posterior end of the head, whereas in adults it is shifted forward and is located approximately above the eye. Modelling shows that this forward shift in the centre of rotation has the advantage of decreasing the moment of inertia and the torque required to rotate the head, but has the disadvantage of slightly increasing the time needed to reach the prey. Thus, the snout lengths of juvenile seahorses appear to be close to optimal, suggesting that they reach levels of performance close to adult levels, which illustrates the pervasive nature of selection on performance in juveniles.

When School Is Not Enough: New Initiatives in Intergenerational Language Transmission in Wales

ERIC Educational Resources Information Center

Edwards, Viv; Newcombe, Lynda Prichard

2005-01-01

This paper examines language reproduction in the family in the context of a highly innovative project in Wales, where the Welsh language has been in decline for over a century. Although Welsh-medium schooling has played a pivotal role in slowing and even reversing language shift in recent decades, there is mounting evidence of the dangers of …

Plant responses, climate pivot points, and trade-offs in water-limited ecosystems

USGS Publications Warehouse

Munson, Seth M.

2013-01-01

Plant species in dryland ecosystems are limited by water availability and may be vulnerable to increases in aridity. Methods are needed to monitor and assess the rate of change in plant abundance and composition in relation to climate, understand the potential for degradation in dryland ecosystems, and forecast future changes in plant species assemblages. I employ nearly a century of vegetation monitoring data from three North American deserts to demonstrate an approach to determine plant species responses to climate and critical points over a range of climatic conditions at which plant species shift from increases to decreases in abundance (climate pivot points). I assess these metrics from a site to regional scale and highlight how these indicators of plant performance can be modified by the physical and biotic environment. For example, shrubs were more responsive to drought and high temperatures on shallow soils with limited capacity to store water and fine-textured soils with slow percolation rates, whereas perennial grasses were more responsive to precipitation in sparse shrublands than in relatively dense grasslands and shrublands, where competition for water is likely more intense. The responses and associated climate pivot points of plant species aligned with their lifespan and structural characteristics, and the relationship between responses and climate pivot points provides evidence of the trade-off between the capacity of a plant species to increase in abundance when water is available and its drought resistance.

The Aharonov–Bohm effect in scattering theory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sitenko, Yu.A., E-mail: yusitenko@bitp.kiev.ua; Vlasii, N.D.

2013-12-15

The Aharonov–Bohm effect is considered as a scattering event with nonrelativistic charged particles of the wavelength which is less than the transverse size of an impenetrable magnetic vortex. The quasiclassical WKB method is shown to be efficient in solving this scattering problem. We find that the scattering cross section consists of two terms, one describing the classical phenomenon of elastic reflection and another one describing the quantum phenomenon of diffraction; the Aharonov–Bohm effect is manifested as a fringe shift in the diffraction pattern. Both the classical and the quantum phenomena are independent of the choice of a boundary condition atmore » the vortex edge, providing that probability is conserved. We show that a propagation of charged particles can be controlled by altering the flux of a magnetic vortex placed on their way. -- Highlights: •Aharonov–Bohm effect as a scattering event. •Impenetrable magnetic vortex of nonzero transverse size. •Scattering cross section is independent of a self-adjoint extension employed. •Classical phenomenon of elastic reflection and quantum phenomenon of diffraction. •Aharonov–Bohm effect as a fringe shift in the diffraction pattern.« less

Impacts of Long-Term Irrigation of Domestic Treated Wastewater on Soil Biogeochemistry and Bacterial Community Structure

PubMed Central

Wafula, Denis; White, John R.; Canion, Andy; Jagoe, Charles; Pathak, Ashish

2015-01-01

Freshwater scarcity and regulations on wastewater disposal have necessitated the reuse of treated wastewater (TWW) for soil irrigation, which has several environmental and economic benefits. However, TWW irrigation can cause nutrient loading to the receiving environments. We assessed bacterial community structure and associated biogeochemical changes in soil plots irrigated with nitrate-rich TWW (referred to as pivots) for periods ranging from 13 to 30 years. Soil cores (0 to 40 cm) were collected in summer and winter from five irrigated pivots and three adjacently located nonirrigated plots. Total bacterial and denitrifier gene abundances were estimated by quantitative PCR (qPCR), and community structure was assessed by 454 massively parallel tag sequencing (MPTS) of small-subunit (SSU) rRNA genes along with terminal restriction fragment length polymorphism (T-RFLP) analysis of nirK, nirS, and nosZ functional genes responsible for denitrification of the TWW-associated nitrate. Soil physicochemical analyses showed that, regardless of the seasons, pH and moisture contents (MC) were higher in the irrigated (IR) pivots than in the nonirrigated (NIR) plots; organic matter (OM) and microbial biomass carbon (MBC) were higher as a function of season but not of irrigation treatment. MPTS analysis showed that TWW loading resulted in the following: (i) an increase in the relative abundance of Proteobacteria, especially Betaproteobacteria and Gammaproteobacteria; (ii) a decrease in the relative abundance of Actinobacteria; (iii) shifts in the communities of acidobacterial groups, along with a shift in the nirK and nirS denitrifier guilds as shown by T-RFLP analysis. Additionally, bacterial biomass estimated by genus/group-specific real-time qPCR analyses revealed that higher numbers of total bacteria, Acidobacteria, Actinobacteria, Alphaproteobacteria, and the nirS denitrifier guilds were present in the IR pivots than in the NIR plots. Identification of the nirK-containing microbiota as a proxy for the denitrifier community indicated that bacteria belonged to alphaproteobacteria from the Rhizobiaceae family within the agroecosystem studied. Multivariate statistical analyses further confirmed some of the above soil physicochemical and bacterial community structure changes as a function of long-term TWW application within this agroecosystem. PMID:26253672

Systemic Review of Anatomic Single- Versus Double-Bundle Anterior Cruciate Ligament Reconstruction: Does Femoral Tunnel Drilling Technique Matter?

PubMed

Zhang, Yang; Xu, Caiqi; Dong, Shiqui; Shen, Peng; Su, Wei; Zhao, Jinzhong

2016-09-01

To provide an up-to-date assessment of the difference between anatomic double-bundle anterior cruciate ligament (ACL) reconstruction (DB-ACLR) and anatomic single-bundle ACL reconstruction (SB-ACLR). We hypothesized that anatomic SB-ACLR using independent femoral drilling technique would be able to achieve kinematic stability as with anatomic DB-ACLR. A comprehensive Internet search was performed to identify all therapeutic trials of anatomic DB-ACLR versus anatomic SB-ACLR. Only clinical studies of Level I and II evidence were included. The comparative outcomes were instrument-measured anterior laxity, Lachman test, pivot shift, clinical outcomes including objective/subjective International Knee Documentation Committee (IKDC) score, Lysholm score, Tegner activity scale and complication rates of extension/flexion deficits, graft failure, and early osteoarthritis. Subgroup analyses were performed for femoral tunnel drilling techniques including independent drilling and transtibial (TT) drilling. Twenty-two clinical trials of 2,261 anatomically ACL-reconstructed patients were included in the meta-analysis. Via TT drilling technique, anatomic DB-ACLR led to improved instrument-measured anterior laxity with a standard mean difference (SMD) of -0.42 (95% confidence interval [CI] = -0.81 to -0.02), less rotational instability measured by pivot shift (SMD = 2.76, 95% CI = 1.24 to 6.16), and higher objective IKDC score with odds ratio (OR) of 2.28 (95% CI = 1.19 to 4.36). Via independent drilling technique, anatomic DB-ACLR yielded better pivot shift (SMD = 2.04, 95% CI = 1.36 to 3.05). Anatomic DB-ACLR also revealed statistical significance in subjective IKDC score compared with anatomic SB-ACLR (SMD = 0.27, 95% CI = 0.05 to 0.49). Anatomic DB-ACLR showed better anterior and rotational stability and higher objective IKDC score than anatomic SB-ACLR via TT drilling technique. Via independent drilling technique, however, anatomic DB-ACLR only showed superiority of rotational stability. All clinical function outcomes except subjective IKDC score were not significantly different between anatomic DB-ACLR and SB-ACLR. Level II, meta-analysis of Level I and II studies. Copyright © 2016 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Knee joint kinematics after dynamic intraligamentary stabilization: cadaveric study on a novel anterior cruciate ligament repair technique.

PubMed

Schliemann, Benedikt; Lenschow, Simon; Domnick, Christoph; Herbort, Mirco; Häberli, Janosch; Schulze, Martin; Wähnert, Dirk; Raschke, Michael J; Kösters, Clemens

2017-04-01

Dynamic intraligamentary stabilization (DIS) has been introduced for the repair of acute anterior cruciate ligament (ACL) tears as an alternative to delayed reconstruction. The aim of the present study was to compare knee joint kinematics after DIS to those of the ACL-intact and ACL-deficient knee under simulated Lachman/KT-1000 and pivot-shift tests. We hypothesized that DIS provides knee joint kinematics equivalent to an intact ACL. With the use of a robotic knee simulator, knee kinematics were determined in simulated Lachman/KT-1000 and pivot-shift tests at 0°, 15°, 30°, 60°, and 90° of flexion in eight cadaveric knees under the following conditions: (1) intact ACL, (2) ACL deficiency, (3) DIS with a preload of 60 N, and (4) DIS with a preload of 80 N. Statistical analyses were performed using two-factor repeated-measures analysis of variance. The significance level was set at a p value of <0.05. After DIS with a preload of either 60 N or 80 N, the anterior translation was significantly reduced in the simulated Lachman/KT-1000 and pivot-shift tests when compared to the ACL-deficient knee (p < 0.05). No significant differences were observed between the DIS reconstruction with a preload of 80 N and the intact ACL with regard to anterior laxity in either test. However, DIS with a preload of only 60 N was not able to restore knee joint kinematics to that of an intact knee in all degrees of flexion. DIS with a preload of 80 N restores knee joint kinematics comparable to that of an ACL-intact knee and is therefore capable of providing knee joint stability during ACL healing. DIS therefore provides a new technique for primary ACL repair with superior biomechanical properties in comparison with other techniques that have been described previously, although further clinical studies are required to determine its usefulness in clinical settings.

'Benefits cycle' replacing premium cycle as consumerism takes hold.

PubMed

2002-05-01

The traditional premium cycle of ups and downs in rates is giving way to a new phenomenon--driven by the advent of consumerism in health care--termed the "benefits cycle" by one consultant. Rather than shifts in rates, he argues, the future will see shifts in benefits packages.

Methanogenesis-induced pH–Eh shifts drives aqueous metal(loid) mobility in sulfide mineral systems under CO2 enriched conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harvey, Omar R.; Qafoku, Nikolla; Cantrell, Kirk J.

2016-01-15

Accounting for microbially-mediated CO2 transformation is pivotal to assessing geochemical implications for elevated CO2 in subsurface environments. A series of batch-reactor experiments were conducted to decipher links between autotrophic methanogenesis, CO2 dynamics and aqueous Fe, As and Pb concentrations in the presence of sulfide minerals. Microbially-mediated solubility-trapping followed by pseudo-first order reduction of HCO3- to CH4 (k’ = 0.28-0.59 d-1) accounted for 95% of the CO2 loss from methanogenic experiments. Bicarbonate-to-methane reduction was pivotal in the mitigation of CO2-induced acidity (~1 pH unit) and enhancement of reducing conditions (Eh change from -0.215 to -0.332V ). Methanogenesis-associated shifts in pH-Eh valuesmore » showed no significant effect on aqueous Pb but favored, 1) increased aqueous As as a result of microbially-mediated dissolution of arsenopyrite and 2) decreased aqueous Fe due to mineral-trapping of CO2-mobilized Fe as Fe-carbonate. Its order of occurrence (and magnitude), relative to solubility- and mineral-trapping, highlighted the potential for autotrophic methanogenesis to modulate both carbon sequestration and contaminant mobility in CO2-impacted subsurface environments.« less

The Risky Shift in Policy Decision Making: A Comparative Analysis

ERIC Educational Resources Information Center

Wilpert, B.; And Others

1976-01-01

Based on analysis of data on 432 decision-makers from around the world, this study examines the decision-making phenomenon that individuals tend to move toward riskier decisions after group discussion. Findings of the analysis contradicted earlier studies, showing a consistent shift toward greater risk avoidance. Available from Elsevier Scientific…

The Role of Personal Choice in Individual Language Shift

ERIC Educational Resources Information Center

Morse, Kira Gulko

2012-01-01

The existing literature views the phenomenon of language shift mostly on the societal, or macro, level, which takes the focus away from individual cases. This investigation provides an alternative perspective to the currently prevalent view. The purpose of this phenomenological study is to develop an understanding of the role of personal choice in…

Retrieval-Induced versus Context-Induced Forgetting: Does Retrieval-Induced Forgetting Depend on Context Shifts?

ERIC Educational Resources Information Center

Soares, Julia S.; Polack, Cody W.; Miller, Ralph R.

2016-01-01

Retrieval-induced forgetting (RIF) is the observation that retrieval of target information causes forgetting of related nontarget information. A number of accounts of this phenomenon have been proposed, including a context-shift-based account (Jonker, Seli, & Macleod, 2013). This account proposes that RIF occurs as a result of the context…

Hydride ions in oxide hosts hidden by hydroxide ions

PubMed Central

Hayashi, Katsuro; Sushko, Peter V.; Hashimoto, Yasuhiro; Shluger, Alexander L.; Hosono, Hideo

2014-01-01

The true oxidation state of formally ‘H−’ ions incorporated in an oxide host is frequently discussed in connection with chemical shifts of 1H nuclear magnetic resonance spectroscopy, as they can exhibit values typically attributed to H+. Here we systematically investigate the link between geometrical structure and chemical shift of H− ions in an oxide host, mayenite, with a combination of experimental and ab initio approaches, in an attempt to resolve this issue. We demonstrate that the electron density near the hydrogen nucleus in an OH− ion (formally H+ state) exceeds that in an H− ion. This behaviour is the opposite to that expected from formal valences. We deduce a relationship between the chemical shift of H− and the distance from the H− ion to the coordinating electropositive cation. This relationship is pivotal for resolving H− species that are masked by various states of H+ ions. PMID:24662678

Is impaired set-shifting a feature of "pure" anorexia nervosa? Investigating the role of depression in set-shifting ability in anorexia nervosa and unipolar depression.

PubMed

Giel, Katrin E; Wittorf, Andreas; Wolkenstein, Larissa; Klingberg, Stefan; Drimmer, Eyal; Schönenberg, Michael; Rapp, Alexander M; Fallgatter, Andreas J; Hautzinger, Martin; Zipfel, Stephan

2012-12-30

Impaired set-shifting has been reported in patients with anorexia nervosa (AN) and in patients with affective disorders, including major depression. Due to the prevalent comorbidity of major depression in AN, this study aimed to examine the role of depression in set-shifting ability. Fifteen patients with AN without a current comorbid depression, 20 patients with unipolar depression (UD) and 35 healthy control participants were assessed using the Trail Making Test (TMT), the Wisconsin Card Sorting Test (WCST) and a Parametric Go/No-Go Test (PGNG). Set-shifting ability was intact in patients with AN without a comorbid depression. However, patients with UD performed significantly poorer in all three tasks compared to AN patients and in the TMT compared to healthy control participants. In both patient groups, set-shifting ability was moderately negatively correlated with severity of depressive symptoms, but was unrelated to BMI and severity of eating disorder symptoms in AN patients. Our results suggest a pivotal role of comorbidity for neuropsychological functioning in AN. Impairments of set-shifting ability in AN patients may have been overrated and may partly be due to comorbid depressive disorders in investigated patients. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Comparison of quantitative evaluation between cutaneous and transosseous inertial sensors in anterior cruciate ligament deficient knee: A cadaveric study.

PubMed

Murase, Atsunori; Nozaki, Masahiro; Kobayashi, Masaaki; Goto, Hideyuki; Yoshida, Masahito; Yasuma, Sanshiro; Takenaga, Tetsuya; Nagaya, Yuko; Mizutani, Jun; Okamoto, Hideki; Iguchi, Hirotaka; Otsuka, Takanobu

2017-09-01

Recently several authors have reported on the quantitative evaluation of the pivot-shift test using cutaneous fixation of inertial sensors. Before utilizing this sensor for clinical studies, it is necessary to evaluate the accuracy of cutaneous sensor in assessing rotational knee instability. To evaluate the accuracy of inertial sensors, we compared cutaneous and transosseous sensors in the quantitative assessment of rotational knee instability in a cadaveric setting, in order to demonstrate their clinical applicability. Eight freshly frozen human cadaveric knees were used in this study. Inertial sensors were fixed on the tibial tuberosity and directly fixed to the distal tibia bone. A single examiner performed the pivot shift test from flexion to extension on the intact knees and ACL deficient knees. The peak overall magnitude of acceleration and the maximum rotational angular velocity in the tibial superoinferior axis was repeatedly measured with the inertial sensor during the pivot shift test. Correlations between cutaneous and transosseous inertial sensors were evaluated, as well as statistical analysis for differences between ACL intact and ACL deficient knees. Acceleration and angular velocity measured with the cutaneous sensor demonstrated a strong positive correlation with the transosseous sensor (r = 0.86 and r = 0.83). Comparison between cutaneous and transosseous sensor indicated significant difference for the peak overall magnitude of acceleration (cutaneous: 10.3 ± 5.2 m/s 2 , transosseous: 14.3 ± 7.6 m/s 2 , P < 0.01) and for the maximum internal rotation angular velocity (cutaneous: 189.5 ± 99.6 deg/s, transosseous: 225.1 ± 103.3 deg/s, P < 0.05), but no significant difference for the maximum external rotation angular velocity (cutaneous: 176.1 ± 87.3 deg/s, transosseous: 195.9 ± 106.2 deg/s, N.S). There is a positive correlation between cutaneous and transosseous inertial sensors. Therefore, this study indicated that the cutaneous inertial sensors could be used clinically for quantifying rotational knee instability, irrespective of the location of utilization. Copyright © 2017 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.

Dynamical manifestation of an evolving Berry phase as a frequency shift of the resonance transition between two eigenstates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Toriyama, Koichi; Oguchi, Akihide; Morinaga, Atsuo

2011-12-15

We investigate the phenomenon that a Berry phase evolving linearly in time induces a frequency shift of the resonance transition between two eigenstates, regardless of whether or not they are superposed. Using the magnetic-field-insensitive two-photon microwave--radio-frequency transition, which is free of any other dynamical frequency shift, we demonstrate that the frequency shift caused by a uniform rotation of the magnetic field corresponds to the derivative of the Berry phase with respect to time and depends on the direction of rotation of the magnetic field.

Effect of a Surprising Downward Shift in Reinforcer Value on Stimulus Over-Selectivity in a Simultaneous Discrimination Procedure

ERIC Educational Resources Information Center

Reynolds, Gemma; Reed, Phil

2013-01-01

Stimulus over-selectivity refers to the phenomenon whereby behavior is controlled by a subset of elements in the environment at the expense of other equally salient aspects of the environment. The experiments explored whether this cue interference effect was reduced following a surprising downward shift in reinforcer value. Experiment 1 revealed…

Dating the Shift to English in the Financial Accounts of Some London Livery Companies: A Reappraisal

ERIC Educational Resources Information Center

Alcolado Carnicero, José Miguel

2015-01-01

A mixed-language phenomenon such as language shift has been acknowledged to constitute one of the hallmarks of the manuscripts in which the members of the City of London livery companies recorded their financial transactions during the late medieval period. Despite these texts having been studied by scholars in very diverse disciplines,…

Half-peroneus-longus-tendon graft augmentation for unqualified hamstring tendon graft of anterior cruciate ligament reconstruction.

PubMed

Liu, Chung-Ting; Lu, Yung-Chang; Huang, Chang-Hung

2015-09-01

In some situations, harvested hamstring tendon grafts are not qualified for anterior cruciate ligament (ACL) reconstruction. This study aimed to present a reinforcing method with additional half peroneus longus tendon (half-PLT) graft augmentation. Eight cases underwent ACL reconstruction with unqualified hamstring tendon grafts (diameter <7 mm) and were salvaged by additional half-PLT graft augmentation. The pivot shift test and KT-1000 tests were performed 3 years after surgery. Functional evaluation of subjective International Knee Documentation Committee (IKDC) and Lysholm scores was also done. In addition, Foot and Ankle Disability Index (FADI) scores were used to evaluate the function of the ankle donor site. The diameter of unqualified four-strand hamstring tendon grafts was 6.2 mm on average (range, 6.0-6.5 mm). The average diameter of hamstring grafts with half-PLT augmentation was 9.6 mm (range, 9.5-10.0 mm). The pivot shift test was negative in all patients. No significant differences between normal and abnormal knees were found by KT-1000. The average IKDC score was 86.0 (range, 83 to 89), and the average Lysholm score was 84.4 (range, 80-90). The average FADI score for the donor sites of half-PLT was 135.8 (range, 134-136). Additional half-PLT can successfully and safely reinforce unqualified hamstring tendon grafts for ACL reconstruction.

Quantum anomalous Bloch-Siegert shift in Weyl semimetal

NASA Astrophysics Data System (ADS)

Kumar, Upendra; Kumar, Vipin; Enamullah, Setlur, Girish S.

2018-05-01

A periodic exchange of energy between the light field and two level system is known as Rabi oscillations. The Bloch-Siegert shift (BSS) is a shift in Rabi oscillation resonance condition, when the driving field is sufficiently strong. There are new type of oscillations exhibit in Weyl semimetal at far from resonance, known as anomalous Rabi oscillation. In this work, we study the phenomenon of the Bloch-Siegert shift in Weyl semimetal at far from resonance called anomalous Bloch-Siegert shift (ABSS) by purely quantum mechanical treatment and describe it's anisotropic nature. A fully numerical solution of the Floquet-Bloch equations unequivocally establishes the presence of not only anomalous Rabi oscillations in these systems but also their massless character.

Fast-scale non-linear distortion analysis of peak-current-controlled buck-boost inverters

NASA Astrophysics Data System (ADS)

Zhang, Hao; Dong, Shuai; Yi, Chuanzhi; Guan, Weimin

2018-02-01

This paper deals with fast-scale non-linear distortion behaviours including asymmetrical period-doubling bifurcation and zero-crossing distortion in peak-current-controlled buck-boost inverters. The underlying mechanisms of the fast-scale non-linear distortion behaviours in inverters are revealed. The folded bifurcation diagram is presented to analyse the asymmetrical phenomenon of fast-scale period-doubling bifurcation. In view of the effect of phase shift and current ripple, the analytical expressions for one pair of critical phase angles are derived by using the design-oriented geometrical current approach. It is shown that the phase shift between inductor current and capacitor voltage should be responsible for the zero-crossing distortion phenomenon. These results obtained here are useful to optimise the circuit design and improve the circuit performance.

Tyrosine isomers mediate the classical phenomenon of concomitant tumor resistance.

PubMed

Ruggiero, Raúl A; Bruzzo, Juan; Chiarella, Paula; di Gianni, Pedro; Isturiz, Martín A; Linskens, Susana; Speziale, Norma; Meiss, Roberto P; Bustuoabad, Oscar D; Pasqualini, Christiane D

2011-11-15

Concomitant tumor resistance (CR) is a phenomenon originally described in 1906 in which a tumor-bearing host is resistant to the growth of secondary tumor implants and metastasis. Although recent studies have indicated that T-cell-dependent processes mediate CR in hosts bearing immunogenic small tumors, manifestations of CR induced by immunogenic and nonimmunogenic large tumors have been associated with an elusive serum factor. In this study, we identify this serum factor as tyrosine in its meta and ortho isoforms. In three different murine models of cancer that generate CR, both meta-tyrosine and ortho-tyrosine inhibited tumor growth. In addition, we showed that both isoforms of tyrosine blocked metastasis in a fourth model that does not generate CR but is sensitive to CR induced by other tumors. Mechanistic studies showed that the antitumor effects of the tyrosine isoforms were mediated, in part, by early inhibition of mitogen-activated protein/extracellular signal-regulated kinase pathway and inactivation of STAT3, potentially driving tumor cells into a state of dormancy. By revealing a molecular basis for the classical phenomenon of CR, our findings may stimulate new generalized approaches to limit the development of metastases that arise after resection of primary tumors, an issue of pivotal importance to oncologists and their patients. ©2011 AACR

State of the cart.

PubMed

Bernstein, C; Weiss, S; Lorenzini, B

1994-03-15

Food on wheels: it's here, there and everywhere. But while some operations rev up cart expansion plans, others have shifted into low gear. Here's an update on that '90s phenomenon: mobile merchandising.

Cooperative Lamb shift and superradiance in an optoelectronic device

NASA Astrophysics Data System (ADS)

Frucci, G.; Huppert, S.; Vasanelli, A.; Dailly, B.; Todorov, Y.; Beaudoin, G.; Sagnes, I.; Sirtori, C.

2017-04-01

When a single excitation is shared between a large number of two-level systems, a strong enhancement of the spontaneous emission appears. This phenomenon is known as superradiance. This enhanced rate can be accompanied by a shift of the emission frequency, the cooperative Lamb shift, issued from the exchange of virtual photons between the emitters. In this work we present a semiconductor optoelectronic device allowing the observation of these two phenomena at room temperature. We demonstrate experimentally and theoretically that plasma oscillations in spatially separated quantum wells interact through real and virtual photon exchange. This gives rise to a superradiant mode displaying a large cooperative Lamb shift.

Co-management as a Catalyst: Pathways to Post-colonial Forestry in the Klamath Basin, California.

PubMed

Diver, Sibyl

2016-01-01

Co-management frameworks are intended to facilitate sustainable resource management and more equitable power sharing between state agencies and Indigenous communities. However, there is significant debate about who benefits from co-management in practice. This article addresses two competing perspectives in the literature, which alternately portrays co-management as an instrument for co-optation or for transformation. Through a case study of co-management negotiations involving the Karuk Tribe and the U.S. Forest Service in the Klamath Basin of Northern California, this study examines how Indigenous communities use co-management to build greater equity in environmental decision-making, despite its limitations. The concept of pivot points is developed to describe how Indigenous communities like the Karuk Tribe are simultaneously following existing state policies and subverting them to shift federal forest management. The pivot point analytic demonstrates one mechanism by which communities are addressing Indigenous self-determination goals and colonial legacies through environmental policy and management.

The effect of work shift configurations on emergency medical dispatch center response.

PubMed

Montassier, Emmanuel; Labady, Julien; Andre, Antoine; Potel, Gilles; Berthier, Frederic; Jenvrin, Joel; Penverne, Yann

2015-01-01

It has been proved that emergency medical dispatch centers (EMDC) save lives by promoting an appropriate allocation of emergency medical service resources. Indeed, optimal dispatcher call duration is pivotal to reduce the time gap between the time a call is placed and the delivery of medical care. However, little is known about the impact of work shift configurations (i.e., work shift duration and work shift rotation throughout the day) and dispatcher call duration. Thus, the objective of our study was to assess the effect of work shift configurations on dispatcher call duration. During a 1-year study period, we analyzed the dispatcher call durations for medical and trauma calls during the 4 different work shift rotations (day, morning, evening, and night) and during the 10-hour work shift of each dispatcher in the EMDC of Nantes. We extracted dispatcher call durations from our advanced telephone system, configured with CC Pulse + (Genesys, Alcatel Lucent), and collected them in a custom designed database (Excel, Microsoft). Afterward, we analyzed these data using linear mixed effects models. During the study period, our EMDC received 408,077 calls. Globally, the mean dispatcher call duration was 107 ± 45 seconds. Based on multivariate linear mixed effects models, the dispatcher call duration was affected by night work shift and work shift duration greater than 8 hours, increasing it by about 10 ± 1 seconds and 4 ± 1 seconds, respectively (both p < 0.001). Our study showed that there was a statistically significant difference in dispatcher call duration over work shift rotation and duration, with longer durations seen over night shifts and shifts over 8 hours. While these differences are small and may not have clinical significance, they may have implications for EMDC efficiency.

Phase shift from a coral to a corallimorph-dominated reef associated with a shipwreck on Palmyra atoll

USGS Publications Warehouse

Work, Thierry M.; Aeby, G.S.; Maragos, J.E.

2008-01-01

Coral reefs can undergo relatively rapid changes in the dominant biota, a phenomenon referred to as phase shift. Various reasons have been proposed to explain this phenomenon including increased human disturbance, pollution, or changes in coral reef biota that serve a major ecological function such as depletion of grazers. However, pinpointing the actual factors potentially responsible can be problematic. Here we show a phase shift from coral to the corallimorpharian Rhodactis howesii associated with a long line vessel that wrecked in 1991 on an isolated atoll (Palmyra) in the central Pacific Ocean. We documented high densities of R. howesii near the ship that progressively decreased with distance from the ship whereas R. howesii were rare to absent in other parts of the atoll. We also confirmed high densities of R. howesii around several buoys recently installed on the atoll in 2001. This is the first time that a phase shift on a coral leef has been unambiguously associated with man-made structures. This association was made, in part, because of the remoteness of Palmyra and its recent history of minimal human habitation or impact. Phase shifts can have long-term negative ramification for coral reefs, and eradication of organisms responsible for phase shifts in marine ecosystems can be difficult, particularly if such organisms cover a large area. The extensive R. howesii invasion and subsequent loss of coral reef habitat at Palmyra also highlights the importance of rapid removal of shipwrecks on corals reefs to mitigate the potential of reef overgrowth by invasives.

Dual regulatory switch confers tighter control on HtrA2 proteolytic activity.

PubMed

Singh, Nitu; D'Souza, Areetha; Cholleti, Anuradha; Sastry, G Madhavi; Bose, Kakoli

2014-05-01

High-temperature requirement protease A2 (HtrA2), a multitasking serine protease that is involved in critical biological functions and pathogenicity, such as apoptosis and cancer, is a potent therapeutic target. It is established that the C-terminal post-synaptic density protein, Drosophila disc large tumor suppressor, zonula occludens-1 protein (PDZ) domain of HtrA2 plays pivotal role in allosteric modulation, substrate binding and activation, as commonly reported in other members of this family. Interestingly, HtrA2 exhibits an additional level of functional modulation through its unique N-terminus, as is evident from 'inhibitor of apoptosis proteins' binding and cleavage. This phenomenon emphasizes multiple activation mechanisms, which so far remain elusive. Using conformational dynamics, binding kinetics and enzymology studies, we addressed this complex behavior with respect to defining its global mode of regulation and activity. Our findings distinctly demonstrate a novel N-terminal ligand-mediated triggering of an allosteric switch essential for transforming HtrA2 to a proteolytically competent state in a PDZ-independent yet synergistic activation process. Dynamic analyses suggested that it occurs through a series of coordinated structural reorganizations at distal regulatory loops (L3, LD, L1), leading to a population shift towards the relaxed conformer. This precise synergistic coordination among different domains might be physiologically relevant to enable tighter control upon HtrA2 activation for fostering its diverse cellular functions. Understanding this complex rheostatic dual switch mechanism offers an opportunity for targeting various disease conditions with tailored site-specific effector molecules. © 2014 FEBS.

Clinical and arthroscopic outcome of single bundle anterior cruciate ligament reconstruction: Comparison of remnant preservation versus conventional technique.

PubMed

Choi, Sungwook; Kim, Myung-Ku; Kwon, Yong Suk; Kang, Hyunseong

2017-10-01

The purpose of this study was to compare the clinical outcomes and second-look arthroscopic findings of remnant preservation technique with those of conventional anterior cruciate ligament (ACL) reconstruction in single bundle ACL reconstructions. One hundred sixty two consecutive patients underwent ACL reconstruction by one surgeon, with 93 patients receiving remnant preservation technique (Group A) and 69 patients receiving conventional ACL reconstruction (Group B). The mean follow-up was 15months. Clinical outcomes were assessed using Lysholm scores and the International Knee Documentation Committee form (IKDC form) evaluation. Post-operative knee stability was evaluated through manual knee laxity evaluation, pivot-shift test, and a Telos device. Differences in post-operative stability (manual knee laxity, pivot shift test and Telos device) were not significant between the groups (p=0.681, p=0.610, p=0.696). And also no significant differences were noted with respect to the IKDC form and the latest Lysholm scores. But in the second-look arthroscopic findings, synovial coverage was confirmed to be excellent in 36% (22/61) of Group A patients and 23% (7/30) of Group B patients. ACL reconstruction with both techniques was found to result in acceptable stability, clinical outcomes and second-look arthroscopic findings. With regard to synovial coverage, the remnant reservation techniques were found to be superior to conventional ACL reconstruction. Level III, retrospective comparative study. Copyright © 2017 Elsevier B.V. All rights reserved.

Short term results of anterior cruciate ligament augmentation in professional and amateur athletes.

PubMed

Yazdi, Hamidreza; Torkaman, Ali; Ghahramani, Morteza; Moradi, Amin; Nazarian, Ara; Ghorbanhoseini, Mohammad

2017-06-01

Anterior cruciate ligament (ACL) reconstruction is a widely accepted procedure; however, controversies exist about ACL augmentation. The purpose of this study was to assess the clinical outcomes of ACL augmentation in professional and amateur athletes with isolated single bundle ACL tears. A consecutive series of professional and amateur athletes with partial ACL tears who underwent selective bundle reconstruction were analyzed. Stability was assessed with the Lachman test, anterior-drawer test, pivot-shift test and KT-1000 arthrometer. Functional assessment was performed using the subjective Lysholm questionnaire. Fifty-six patients were enrolled. The mean follow-up period was 19.3 months. All patients had posterolateral bundle (PLB) tears, and no anteromedial bundle (AMB) tears were found. The Lysholm score improved significantly from 78 (SD = 2.69) preoperatively to 96 (SD = 3.41) postoperatively (P value <0.0001). The pivot-shift test, Lachman test and anterior-drawer test results were negative in all cases postoperatively. Anterior tibial translation from neutral was 4.9 mm (SD = 2.7) preoperatively, and decreased significantly to 2.1 (SD = 0.6) postoperatively, measured with a KT-1000 arthrometer (P value <0.00001). In this study, we showed that ACL augmentation had good results in symptomatic professional and amateur athletes, and although further studies are needed to investigate long-term results, we recommend this surgery for all symptomatic athletic patients, especially those who would like to maintain an active lifestyle. Level of evidence IV.

Drilling the femoral tunnel during ACL reconstruction: transtibial versus anteromedial portal techniques.

PubMed

Tudisco, Cosimo; Bisicchia, Salvatore

2012-08-01

Incorrect bone tunnel position, particularly on the femoral side, is a frequent cause of failed anterior cruciate ligament reconstruction. Several studies have reported that drilling the femoral tunnel through the anteromedial portal allows a more anatomical placement on the lateral femoral condyle and higher knee stability than does transtibial reconstruction.In the current study, the femoral tunnel was drilled with transtibial (n=6) and anteromedial (n=6) portal techniques in 12 cadaveric knees. With appropriate landmarks inserted into bone tunnels, the direction and length of the tunnels were determined on anteroposterior and lateral radiographs. Knee stability was evaluated with a KT1000 arthrometer (MEDmetric Corporation, San Diego, California) and pivot shift test, comparing the pre- and postoperative values of both techniques. Finally, all knees were dissected to enhance vision of the insertion of the reconstructed ligament. The anteromedial portal technique led to better placement of the femoral tunnel in the coronal and sagittal planes, with higher knee stability according to the pivot shift test but not the KT1000 arthrometer. Anatomical and clinical results reported in the literature on transtibial and anteromedial portal techniques are controversial, but most of studies report better results with the anteromedial portal technique, especially regarding rotational stability. The current cadaveric study showed that the anteromedial portal technique provided better tunnel placement on the lateral femoral condyle in the coronal and sagittal planes, with an improvement in the rotational stability of the knee. Copyright 2012, SLACK Incorporated.

Chronic Pain in Inflammatory Arthritis: Mechanisms, Metrology, and Emerging Targets—A Focus on the JAK-STAT Pathway

PubMed Central

Salaffi, Fausto; Giacobazzi, Giovanni

2018-01-01

Chronic pain is nowadays considered not only the mainstay symptom of rheumatic diseases but also “a disease itself.” Pain is a multidimensional phenomenon, and in inflammatory arthritis, it derives from multiple mechanisms, involving both synovitis (release of a great number of cytokines) and peripheral and central pain-processing mechanisms (sensitization). In the last years, the JAK-STAT pathway has been recognized as a pivotal component both in the inflammatory process and in pain amplification in the central nervous system. This paper provides a summary on pain in inflammatory arthritis, from pathogenesis to clinimetric instruments and treatment, with a focus on the JAK-STAT pathway. PMID:29623147

Third-space fluid shift in elderly patients undergoing gastrointestinal surgery: Part 1: Pathophysiological mechanisms.

PubMed

Redden, Maurine; Wotton, Karen

2002-06-01

Third-space fluid shift, the movement of body fluid to a non-functional space, is a frequently occurring and potentially fatal clinical phenomenon. Little published research exists however in medical or nursing journals concerning its incidence, significance and ramifications in elderly patients undergoing major gastrointestinal surgery. This initial article, part I, explores fluid movement between fluid compartments and uses these principles to discuss the pathophysiology of the two distinct phases of third-space fluid shift. Part II will examine the criteria nurses could use in the clinical assessment of patients in both first and second phases third-space fluid shift and discuss the clinical reliability of these criteria.

Immune Reconstitution Reactions in Human Immunodeficiency Virus–Negative Patients

PubMed Central

Scharschmidt, Tiffany C.; Amerson, Erin H.; Rosenberg, Oren S.; Jacobs, Richard A.; McCalmont, Timothy H.; Shinkai, Kanade

2013-01-01

Background Immune reconstitution inflammatory syndrome (IRIS) is a phenomenon initially described in patients with human immunodeficiency virus. Upon initiation of combination antiretroviral therapy, recovery of cellular immunity triggers inflammation to a preexisting infection or antigen that causes paradoxical worsening of clinical disease. A similar phenomenon can occur in human immunodeficiency virus–negative patients, including pregnant women, neutropenic hosts, solidorgan or stem cell transplant recipients, and patients receiving tumor necrosis factor inhibitors. Observations We report a case of leprosy unmasking and downgrading reaction after stem cell transplantation that highlights some of the challenges inherent to the diagnosis of IRIS, especially in patients without human immunodeficiency virus infection, as well as review the spectrum of previously reported cases of IRIS reactions in this population. Conclusions The mechanism of immune reconstitution reactions is complex and variable, depending on the underlying antigen and the mechanism of immunosuppression or shift in immune status. Use of the term IRIS can aid our recognition of an important phenomenon that occurs in the setting of immunosuppression or shifts in immunity but should not deter us from thinking critically about the distinct processes that underlie this heterogeneous group of conditions. PMID:23324760

Acoustic levitation and the Boltzmann-Ehrenfest principle

NASA Technical Reports Server (NTRS)

Putterman, S.; Rudnick, Joseph; Barmatz, M.

1989-01-01

The Boltzmann-Ehrenfest principle of adiabatic invariance relates the acoustic potential acting on a sample positioned in a single-mode cavity to the shift in resonant frequency caused by the presence of this sample. This general and simple relation applies to samples and cavities of arbitrary shape, dimension, and compressibility. Positioning forces and torques can, therefore, be determined from straightforward measurements of frequency shifts. Applications to the Rayleigh disk phenomenon and levitated cylinders are presented.

Measurement of Critical Contact Angle in a Microgravity Space Experiment

NASA Technical Reports Server (NTRS)

Concus, P.; Finn, R.; Weislogel, M.

1998-01-01

Mathematical theory predicts that small changes in container shape or in contact angle can give rise to large shifts of liquid in a microgravity environment. This phenomenon was investigated in the Interface Configuration Experiment on board the USML-2 Space Shuttle flight. The experiment's "double proboscis" containers were designed to strike a balance between conflicting requirements of sizable volume of liquid shift (for ease of observation) and abruptness of the shift (for accurate determination of critical contact angle). The experimental results support the classical concept of macroscopic contact angle and demonstrate the role of hysteresis in impeding orientation toward equilibrium.

Measurement of Critical Contact Angle in a Microgravity Space Experiment

NASA Technical Reports Server (NTRS)

Concus, P.; Finn, R.; Weislogel, M.

1998-01-01

Mathematical theory predicts that small changes in container shape or in contact angle can give rise to large shifts of liquid in a microgravity environment. This phenomenon was investigated in the Interface Configuration Experiment on board the USMT,2 Space Shuttle flight. The experiment's "double proboscis" containers were designed to strike a balance between conflicting requirements of sizable volume of liquid shift (for ease of observation) and abruptness of the shift (for accurate determination of critical contact angle). The experimental results support the classical concept of macroscopic contact angle and demonstrate the role of hysteresis in impeding orientation toward equilibrium.

Origin of Degradation Phenomenon under Drain Bias Stress for Oxide Thin Film Transistors using IGZO and IGO Channel Layers

PubMed Central

Bak, Jun Yong; Kang, Youngho; Yang, Shinhyuk; Ryu, Ho-Jun; Hwang, Chi-Sun; Han, Seungwu; Yoon, Sung-Min

2015-01-01

Top-gate structured thin film transistors (TFTs) using In-Ga-Zn-O (IGZO) and In-Ga-O (IGO) channel compositions were investigated to reveal a feasible origin for degradation phenomenon under drain bias stress (DBS). DBS-driven instability in terms of VTH shift, deviation of the SS value, and increase in the on-state current were detected only for the IGZO-TFT, in contrast to the IGO-TFT, which did not demonstrate VTH shift. These behaviors were visually confirmed via nanoscale transmission electron microscopy and energy-dispersive x-ray spectroscopy observations. To understand the degradation mechanism, we performed ab initio molecular dynamic simulations on the liquid phases of IGZO and IGO. The diffusivities of Ga and In atoms were enhanced in IGZO, confirming the degradation mechanism to be increased atomic diffusion. PMID:25601183

Origin of degradation phenomenon under drain bias stress for oxide thin film transistors using IGZO and IGO channel layers.

PubMed

Bak, Jun Yong; Kang, Youngho; Yang, Shinhyuk; Ryu, Ho-Jun; Hwang, Chi-Sun; Han, Seungwu; Yoon, Sung-Min

2015-01-20

Top-gate structured thin film transistors (TFTs) using In-Ga-Zn-O (IGZO) and In-Ga-O (IGO) channel compositions were investigated to reveal a feasible origin for degradation phenomenon under drain bias stress (DBS). DBS-driven instability in terms of V(TH) shift, deviation of the SS value, and increase in the on-state current were detected only for the IGZO-TFT, in contrast to the IGO-TFT, which did not demonstrate V(TH) shift. These behaviors were visually confirmed via nanoscale transmission electron microscopy and energy-dispersive x-ray spectroscopy observations. To understand the degradation mechanism, we performed ab initio molecular dynamic simulations on the liquid phases of IGZO and IGO. The diffusivities of Ga and In atoms were enhanced in IGZO, confirming the degradation mechanism to be increased atomic diffusion.

Posterior medial meniscus-femoral insertion into the anterior cruciate ligament. A case report.

PubMed

Bhargava, A; Ferrari, D A

1998-03-01

Medial meniscal anomalies are rare. The anterior horn insertion into the anterior cruciate ligament is the most common. In the course of an arthroscopy for torn lateral meniscus, an anomalous band in continuity with the posterior horn of the medial meniscus was observed to insert into the anterior cruciate ligament. Although the tibial portion of the anterior cruciate was redundant, the anomalous band provided tension to the anterior cruciate ligament and a negative pivot shift. A previously unreported posterior medial meniscal femoral insertion is described.

Bloch-Siegert shift in an interacting Bose-Einstein condensate

NASA Astrophysics Data System (ADS)

Zhang, Jinyi; Eigen, Christoph; Lopes, Raphael; Garratt, Sam; Rousso, David; Smith, Robert P.; Hadzibabic, Zoran; Navon, Nir

2017-04-01

The Bloch-Siegert shift (BSS) is a paradigmatic frequency shift that arises from the nonlinear response of a two-level system (TLS) subjected to strong driving fields. When a TLS is driven by a linearly polarized field, the co-rotating-wave component leads to the famous Rabi oscillations. By contrast the co-rotating-wave component, whose role is usually neglected in a weak driving, leads to a frequency shift of the TLS resonance frequency. This phenomenon is encountered in various areas, from quantum optics to nuclear magnetic resonance.Here, we investigate the BSS in a box-trapped 87 Rb Bose-Einstein condensate (BEC) driven by a strong oscillating magnetic field gradient. By tuning the chemical potential of the gas, we investigate how the BSS evolves from the ideal shift of the two lowest energy levels of a single particle in a box to the unexplored shift of long-wavelength collective excitations of the interacting BEC.

Charge injection from gate electrode by simultaneous stress of optical and electrical biases in HfInZnO amorphous oxide thin film transistor

NASA Astrophysics Data System (ADS)

Kwon, Dae Woong; Kim, Jang Hyun; Chang, Ji Soo; Kim, Sang Wan; Sun, Min-Chul; Kim, Garam; Kim, Hyun Woo; Park, Jae Chul; Song, Ihun; Kim, Chang Jung; Jung, U. In; Park, Byung-Gook

2010-11-01

A comprehensive study is done regarding stabilities under simultaneous stress of light and dc-bias in amorphous hafnium-indium-zinc-oxide thin film transistors. The positive threshold voltage (Vth) shift is observed after negative gate bias and light stress, and it is completely different from widely accepted phenomenon which explains that negative-bias stress results in Vth shift in the left direction by bias-induced hole-trapping. Gate current measurement is performed to explain the unusual positive Vth shift under simultaneous application of light and negative gate bias. As a result, it is clearly found that the positive Vth shift is derived from electron injection from gate electrode to gate insulator.

Condensation phenomenon detection through surface plasmon resonance.

PubMed

Ibrahim, Joyce; Al Masri, Mostafa; Veillas, Colette; Celle, Frédéric; Cioulachtjian, Serge; Verrier, Isabelle; Lefèvre, Frédéric; Parriaux, Olivier; Jourlin, Yves

2017-10-02

The aim of this work is to optically detect the condensation of acetone vapor on an aluminum plate cooled down in a two-phase environment (liquid/vapor). Sub-micron period aluminum based diffraction gratings with appropriate properties, exhibiting a highly sensitive plasmonic response, were successfully used for condensation experiments. A shift in the plasmonic wavelength resonance has been measured when acetone condensation on the aluminum surface takes place due to a change of the surrounding medium close to the surface, demonstrating that the surface modification occurs at the very beginning of the condensation phenomenon. This paper presents important steps in comprehending the incipience of condensate droplet and frost nucleation (since both mechanisms are similar) and thus to control the phenomenon by using an optimized engineered surface.

Inner filter effect and the onset of concentration dependent red shift of synchronous fluorescence spectra.

PubMed

Tarai, Madhumita; Mishra, Ashok Kumar

2016-10-12

The phenomenon of concentration dependent red shift, often observed in synchronous fluorescence spectra (SFS) of monofluorophoric as well as multifluorophoric systems at high chromophore concentrations, is known to have good analytical advantages. This was previously understood in terms of large inner filter effect (IFE) through the introduction of a derived absorption spectral profile that closely corresponds to the SFS profile. Using representative monofluorophoric and multifluorophoric systems, it is now explained how the SF spectral maximum changes with concentration of the fluorophore. For dilute solutions of monofluorophores the maximum is unchanged as expected. It is shown here that the onset of red shift of SFS maximum of both the mono as well as the multifluorophoric systems must occur at the derived absorption spectral parameter value of 0.32 that corresponds to the absorbance value of 0.87. This value is unique irrespective of the nature of the fluorophore under study. For monofluorophoric systems, the wavelength of derived absorption spectral maximum and the wavelength of synchronous fluorescence spectral maximum closely correspond with each other in the entire concentration range. In contrast, for multifluorophoric systems like diesel and aqueous humic acid, large deviations were noted that could be explained as to be due to the presence of non-fluorescing chromophores in the system. This work bridges the entire fluorophore concentration range over which the red shift of SFS maximum sets in; and in the process it establishes the importance of the derived absorption spectral parameter in understanding the phenomenon of concentration dependent red shift of SFS maximum. Copyright © 2016 Elsevier B.V. All rights reserved.

[The significance of the Montessori method and phenomenon with a particular view to the therapy of the aphasics (author's transl)].

PubMed

Birchmeier-Nussbaumer, A K

1980-05-01

The methods of the Italian physician Maria Montessori influenced the development of modern learning practices. There is general agreement that the Montessori phenomenon is personality forming. Aspects of this method, which are relevant for the rehabilitation of the brain-damaged and, in particular, the aphasics are presented. Possible shifts of emphasis within the relationship therapist - method - patient are analysed. Examples are used to outline in how far an increasingly patient-oriented therapy can influence the development of the aphasic patient.

The Amateur Scientist.

ERIC Educational Resources Information Center

Walker, Jearl

1983-01-01

Three physics experiments are described, minimizing difficulties for amateur experimenters. One experiment demonstrates the Doppler shift of light, converting the phenomenon into sound. The second measures Planck's constant. The third measures the universal gravitational constant, which does the same in Newton's theory of gravitation. (Author/JN)

Mental Imagery: Functional Mechanisms and Clinical Applications

PubMed Central

Pearson, Joel; Naselaris, Thomas; Holmes, Emily A.; Kosslyn, Stephen M.

2015-01-01

Mental imagery research has weathered both disbelief of the phenomenon and inherent methodological limitations. Here we review recent behavioral, brain imaging, and clinical research that has reshaped our understanding of mental imagery. Research supports the claim that visual mental imagery is a depictive internal representation that functions like a weak form of perception. Brain imaging work has demonstrated that neural representations of mental and perceptual images resemble one another as early as the primary visual cortex (V1). Activity patterns in V1 encode mental images and perceptual images via a common set of low-level depictive visual features. Recent translational and clinical research reveals the pivotal role that imagery plays in many mental disorders and suggests how clinicians can utilize imagery in treatment. PMID:26412097

Photoacoustic Doppler effect from flowing small light-absorbing particles.

PubMed

Fang, Hui; Maslov, Konstantin; Wang, Lihong V

2007-11-02

From the flow of a suspension of micrometer-scale carbon particles, the photoacoustic Doppler shift is observed. As predicted theoretically, the observed Doppler shift equals half of that in Doppler ultrasound and does not depend on the direction of laser illumination. This new physical phenomenon provides a basis for developing photoacoustic Doppler flowmetry, which can potentially be used for detecting fluid flow in optically scattering media and especially low-speed blood flow of relatively deep microcirculation in biological tissue.

Permanent magnetic ferrite based power-tunable metamaterials

NASA Astrophysics Data System (ADS)

Zhang, Guanqiao; Lan, Chuwen; Gao, Rui; Zhou, Ji

2017-08-01

Power-tunable metamaterials based on barium permanent magnetic ferrite have been proposed and fabricated in this research. Scattering parameter measurements confirm a shift in resonant frequency in correlation to changes in incident electromagnetic power within microwave frequency band. The tunable phenomenon represented by a blue-shift in transmission spectra in the metamaterials array can be attributed to a decrease in saturation magnetization resulting from FMR-induced temperature elevation upon resonant conditions. This power-dependent behavior offers a simple and practical route towards dynamically fine-tunable ferrite metamaterials.

Clinical diagnosis of partial or complete anterior cruciate ligament tears using patients' history elements and physical examination tests.

PubMed

Décary, Simon; Fallaha, Michel; Belzile, Sylvain; Martel-Pelletier, Johanne; Pelletier, Jean-Pierre; Feldman, Debbie; Sylvestre, Marie-Pierre; Vendittoli, Pascal-André; Desmeules, François

2018-01-01

To assess the diagnostic validity of clusters combining history elements and physical examination tests to diagnose partial or complete anterior cruciate ligament (ACL) tears. Prospective diagnostic study. Orthopaedic clinics (n = 2), family medicine clinics (n = 2) and community-dwelling. Consecutive patients with a knee complaint (n = 279) and consulting one of the participating orthopaedic surgeons (n = 3) or sport medicine physicians (n = 2). Not applicable. History elements and physical examination tests performed independently were compared to the reference standard: an expert physicians' composite diagnosis including history elements, physical tests and confirmatory magnetic resonance imaging. Penalized logistic regression (LASSO) was used to identify history elements and physical examination tests associated with the diagnosis of ACL tear and recursive partitioning was used to develop diagnostic clusters. Diagnostic accuracy measures including sensitivity (Se), specificity (Sp), predictive values and positive and negative likelihood ratios (LR+/-) with associated 95% confidence intervals (CI) were calculated. Forty-three individuals received a diagnosis of partial or complete ACL tear (15.4% of total cohort). The Lachman test alone was able to diagnose partial or complete ACL tears (LR+: 38.4; 95%CI: 16.0-92.5). Combining a history of trauma during a pivot with a "popping" sensation also reached a high diagnostic validity for partial or complete tears (LR+: 9.8; 95%CI: 5.6-17.3). Combining a history of trauma during a pivot, immediate effusion after trauma and a positive Lachman test was able to identify individuals with a complete ACL tear (LR+: 17.5; 95%CI: 9.8-31.5). Finally, combining a negative history of pivot or a negative popping sensation during trauma with a negative Lachman or pivot shift test was able to exclude both partial or complete ACL tears (LR-: 0.08; 95%CI: 0.03-0.24). Diagnostic clusters combining history elements and physical examination tests can support the differential diagnosis of ACL tears compared to various knee disorders.

Paradigm shift in consciousness research: the child's self-awareness and abnormalities in autism, ADHD and schizophrenia.

PubMed

Lou, Hans C

2012-02-01

Self-awareness is a pivotal component of any conscious experience and conscious self-regulation of behaviour. A paralimbic network is active, specific and causal in self-awareness. Its regions interact by gamma synchrony. Gamma synchrony develops throughout infancy, childhood and adolescence into adulthood and is regulated by dopamine and other neurotransmitters via GABA interneurons. Major derailments of this network and self-awareness occur in developmental disorders of conscious self-regulation like autism, attention deficit hyperactivity disorder (ADHD) and schizophrenia. Recent research on conscious experience is no longer limited to the study of neural 'correlations' but is increasingly lending itself to the study of causality. This paradigm shift opens new perspectives for understanding the neural mechanisms of the developing self and the causal effects of their disturbance in developmental disorders. © 2011 The Author(s)/Acta Paediatrica © 2011 Foundation Acta Paediatrica.

Intra-ligamentary autologous conditioned plasma and healing response to treat partial ACL ruptures.

PubMed

Koch, Matthias; Matteo, Berardo Di; Eichhorn, Jürgen; Zellner, Johannes; Mayr, Felix; Krutsch, Werner; Achenbach, Leonard; Woehl, Rebecca; Nerlich, Michael; Angele, Peter

2018-05-01

Conservative treatment of partial ACL ruptures is associated with a high failure rate, and often patients undergo ACL reconstruction. ACL preservation by trephination of the ACL origin and application of Autologous Conditioned Plasma (ACP) seems to be an intriguing new treatment option to favour ACL tissue healing and avoid traditional reconstruction. The aim of this study was to describe the mid-term outcomes of this new ACL preserving technique. Twenty-four patients (mean age 41.8 years) affected by partial rupture of one or both ACL bundles were included in the present trial. The partial ACL tears were arthroscopically assessed and classified according to a new five step grading system. All patients were treated by trephination of the femoral ACL stump and intra-ligamentary application of ACP. The postoperative outcome was evaluated by both subjective scores and stability testing up to a mean of 25.1 months' follow-up. Adverse events and failure rate were also documented. Clinical outcome was good to excellent with IKDC subjective 82.7 (SD 11.8), Lysholm 87.6 (SD 8.1), Tegner 5.3 (SD 2.1), Cincinnati 88.7 (SD 14.8). The failure rate (i.e. persisting knee instability assessed clinically or by rolimeter) was 12.5%. At objective measurements, knee joints showed a firm endpoint in Lachman test, negative pivot shift phenomenon and a significant reduction in AP-laxity compared to pre-operative status by rolimeter testing (p = 0.002). Return to sport practice was achieved after mean 4.8 months (SD 4.1). ACL stump trephination and concomitant intra-ligamentary application of ACP revealed promising results at mid-term follow-up to treat partial ACL lesions.

Patients Covertly Recording Clinical Encounters: Threat or Opportunity? A Qualitative Analysis of Online Texts

PubMed Central

Tsulukidze, Maka; Grande, Stuart W.; Thompson, Rachel; Rudd, Kenneth; Elwyn, Glyn

2015-01-01

Background The phenomenon of patients covertly recording clinical encounters has generated controversial media reports. This study aims to examine the phenomenon and analyze the underlying issues. Methods and Findings We conducted a qualitative analysis of online posts, articles, blogs, and forums (texts) discussing patients covertly recording clinical encounters. Using Google and Google Blog search engines, we identified and analyzed 62 eligible texts published in multiple countries between 2006 and 2013. Thematic analysis revealed four key themes: 1) a new behavior that elicits strong reactions, both positive and negative, 2) an erosion of trust, 3) shifting patient-clinician roles and relationships, and 4) the existence of confused and conflicting responses. When patients covertly record clinical encounters – a behavior made possible by various digital recording technologies – strong reactions are evoked among a range of stakeholders. The behavior represents one consequence of an erosion of trust between patients and clinicians, and when discovered, leads to further deterioration of trust. Confused and conflicting responses to the phenomenon by patients and clinicians highlight the need for policy guidance. Conclusions This study describes strong reactions, both positive and negative, to the phenomenon of patients covertly recording clinical encounters. The availability of smartphones capable of digital recording, and shifting attitudes to patient-clinician relationships, seems to have led to this behavior, mostly viewed as a threat by clinicians but as a welcome and helpful innovation by some patients, possibly indicating a perception of subordination and a lack of empowerment. Further examination of this tension and its implications is needed. PMID:25933002

Direction-dependent waist-shift-difference of Gaussian beam in a multiple-pass zigzag slab amplifier and geometrical optics compensation method.

PubMed

Li, Zhaoyang; Kurita, Takashi; Miyanaga, Noriaki

2017-10-20

Zigzag and non-zigzag beam waist shifts in a multiple-pass zigzag slab amplifier are investigated based on the propagation of a Gaussian beam. Different incident angles in the zigzag and non-zigzag planes would introduce a direction-dependent waist-shift-difference, which distorts the beam quality in both the near- and far-fields. The theoretical model and analytical expressions of this phenomenon are presented, and intensity distributions in the two orthogonal planes are simulated and compared. A geometrical optics compensation method by a beam with 90° rotation is proposed, which not only could correct the direction-dependent waist-shift-difference but also possibly average the traditional thermally induced wavefront-distortion-difference between the horizontal and vertical beam directions.

Observation of the Goos-Hänchen shift with neutrons.

PubMed

de Haan, Victor-O; Plomp, Jeroen; Rekveldt, Theo M; Kraan, Wicher H; van Well, Ad A; Dalgliesh, Robert M; Langridge, Sean

2010-01-08

The Goos-Hänchen effect is a spatial shift along an interface resulting from an interference effect that occurs for total internal reflection. This phenomenon was suggested by Sir Isaac Newton, but it was not until 1947 that the effect was experimentally observed by Goos and Hänchen. We provide the first direct, absolute, experimental determination of the Goos-Hänchen shift for a particle experiencing a potential well as required by quantum mechanics: namely, wave-particle duality. Here, the particle is a spin-polarized neutron reflecting from a film of magnetized material. We detect the effect through a subtle change in polarization of the neutron. Here, we demonstrate, through experiment and theory, that neutrons do exhibit the Goos-Hänchen effect and postulate that the associated time shift should also be observable.

In Pursuit of Internal Waves

NASA Astrophysics Data System (ADS)

Peacock, Thomas

2014-11-01

Orders of magnitude larger than surface waves, and so powerful that their generation impacts the lunar orbit, internal waves, propagating disturbances of a density-stratified fluid, are ubiquitous throughout the ocean and atmosphere. Following the discovery of the phenomenon of ``dead water'' by early Arctic explorers and the classic laboratory visualizations of the curious St. Andrew's Cross internal wave pattern, there has been a resurgence of interest in internal waves, inspired by their pivotal roles in local environmental and global climate processes, and their profound impact on ocean and aerospace engineering. We detail our widespread pursuit of internal waves through theoretical modeling, laboratory experiments and field studies, from the Pacific Ocean one thousand miles north and south of Hawaii, to the South China Sea, and on to the Arctic Ocean. We also describe our recent expedition to surf the most striking internal wave phenomenon of them all: the Morning Glory cloud in remote Northwest Australia. This work was supported by the National Science Foundation through a CAREER Grant OCE-064559 and through Grants OCE-1129757 and OCE-1357434, and by the Office of Naval Research through Grants N00014-09-1-0282, N00014-08-1-0390 and N00014-05-1-0575.

Words and Pictures as Distinct Encoding Categories in Short-Term Memory

ERIC Educational Resources Information Center

Wells, J. Elisabeth

1973-01-01

Results of this experiment show a considerable release from proactive inhibition with a shift from words to pictures or pictures to words, thus adding one more change to the considerable number of category changes which produce the release phenomenon. (Author/CB)

Effects of pivoting neuromuscular training on pivoting control and proprioception.

PubMed

Lee, Song Joo; Ren, Yupeng; Chang, Alison H; Geiger, François; Zhang, Li-Qun

2014-07-01

Pivoting neuromuscular control and proprioceptive acuity may play an important role in anterior cruciate ligament injuries. The goal of this study was to investigate whether pivoting off-axis intensity adjustable neuromuscular control training (POINT) could improve pivoting neuromuscular control, proprioceptive acuity, and functional performance. Among 41 subjects, 21 subjects participated in 18 sessions of POINT (three sessions per week for 6 wk), and 20 subjects served as controls who did their regular workout. Both groups received pre-, mid-, and postintervention evaluations. Propensity score analysis with multivariable regression adjustment was used to investigate the effect of training on pivoting neuromuscular control (pivoting instability, leg pivoting stiffness, maximum internal, and external pivoting angles), proprioceptive acuity, and functional performance in both groups. Compared with the control group, the training group significantly improved pivoting neuromuscular control as reduced pivoting instability, reduced maximum internal and external pivoting angles, increased leg pivoting stiffness, and decreased entropy of time to peak EMG in the gluteus maximus and lateral gastrocnemius under pivoting perturbations. Furthermore, the training group enhanced weight-bearing proprioceptive acuity and improved the single leg hop distance. Improvement of pivoting neuromuscular control in functional weight-bearing activities and task performances after POINT may help develop lower limb injury prevention and rehabilitation methods to reduce anterior cruciate ligament and other musculoskeletal injuries associated with pivoting sports.

Effects of Pivoting Neuromuscular Training on Pivoting Control and Proprioception

PubMed Central

Lee, Song Joo; Ren, Yupeng; Chang, Alison H.; Geiger, François; Zhang, Li-Qun

2014-01-01

Purpose Pivoting neuromuscular control and proprioceptive acuity may play an important role in ACL injuries. The goal of this study was to investigate whether pivoting neuromuscular training on an offaxis elliptical trainer (POINT) could improve pivoting neuromuscular control, proprioceptive acuity, and functional performance. Methods Among 41 subjects, 21 subjects participated in 18 sessions of POINT (3 sessions/week for 6 weeks), and 20 subjects served as controls who did their regular workout. Both groups received pre-, mid-, and post-intervention evaluations. Propensity score analysis with multivariable regression adjustment was used to investigate the effect of training on pivoting neuromuscular control (pivoting instability, leg pivoting stiffness, maximum internal and external pivoting angles), proprioceptive acuity, and functional performance in both groups. Results Compared to the control group, the training group significantly improved pivoting neuromuscular control as reduced pivoting instability, reduced maximum internal and external pivoting angles, increased leg pivoting stiffness, and decreased entropy of time to peak EMG in the gluteus maximus and lateral gastrocnemius under pivoting perturbations. Furthermore, the training group enhanced weight-bearing proprioceptive acuity and improved the single leg hop distance. Conclusion Improvement of pivoting neuromuscular control in functional weight-bearing activities and task performances following POINT may help develop lower limb injury prevention and rehabilitation methods to reduce ACL and other musculoskeletal injuries associated with pivoting sports. PMID:24389517

Vacuum Bloch-Siegert shift in Landau polaritons with ultra-high cooperativity

NASA Astrophysics Data System (ADS)

Li, Xinwei; Bamba, Motoaki; Zhang, Qi; Fallahi, Saeed; Gardner, Geoff C.; Gao, Weilu; Lou, Minhan; Yoshioka, Katsumasa; Manfra, Michael J.; Kono, Junichiro

2018-06-01

A two-level system resonantly interacting with an a.c. magnetic or electric field constitutes the physical basis of diverse phenomena and technologies. However, Schrödinger's equation for this seemingly simple system can be solved exactly only under the rotating-wave approximation, which neglects the counter-rotating field component. When the a.c. field is sufficiently strong, this approximation fails, leading to a resonance-frequency shift known as the Bloch-Siegert shift. Here, we report the vacuum Bloch-Siegert shift, which is induced by the ultra-strong coupling of matter with the counter-rotating component of the vacuum fluctuation field in a cavity. Specifically, an ultra-high-mobility two-dimensional electron gas inside a high-Q terahertz cavity in a quantizing magnetic field revealed ultra-narrow Landau polaritons, which exhibited a vacuum Bloch-Siegert shift up to 40 GHz. This shift, clearly distinguishable from the photon-field self-interaction effect, represents a unique manifestation of a strong-field phenomenon without a strong field.

[Evaluation of the clinical results in patients with symptomatic partial tears of the anterior cruciate ligament diagnosed arthroscopically].

PubMed

Zeman, P; Cibulková, J; Nepraš, P; Koudela, K; Matějka, J

2013-01-01

The study presents a retrospective evaluation of clinical data and arthroscopic findings in a group of our patients with symptomatic knee instability due to a partial tear of the anterior cruciate ligament (ACL). The group included 31 patients diagnosed with symptomatic partial ACL tears, i.e. an isolated tear of the posterolateral (PL) or the anteromedial (AM) bundle. The patients' average age was 26.5 years. A side-to-side difference in ventral knee laxity was assessed using the anterior drawer test and the Lachman test under general anaesthesia before arthroscopy was commenced; rotational knee laxity was evaluated by the pivot shift test. An objective evaluation of side-to-side ventral laxity differences in both knees was performed on the GNRB® arthrometer with an applied pressure of 134 N and 250 N in the conscious patient. During arthroscopic examination, findings on the two ACL bundles were recorded. All 31 patients were diagnosed with symptomatic partial ACL tears, of them 22 had a PL bundle lesion and nine had an AM bundle tear. All patients with PL bundle lesions only reported problems in association with pivot sports, and all patients with AM bundle tears had problems regardless of any sports activities. In all patients with isolated AM bundle tears, the lesion was located close to its femoral attachment. In the patients with PL bundle tears, femoral location was found in 68% and tibial location in 32% of the patients. In the patients with partial PL bundle lesions, + and ++ results in the pivot shift test were recorded in 32% and 68% of the treated patients, respectively. The Lachman test showed + and ++ results in 71% and 9% of the patients, respectively. The anterior drawer test had negative results in 87% and positive + results in 13% of the patients. The side-to-side difference on the GNRB arthrometer ranged from 0.4 to 2.3 mm at a pressure of 134 N and from 1.2 to 4.2 mm at 250 N in the patients with isolated PL bundle lesions. In the patients with AM bundle lesions, the results were as follows: pivot shift test, 89% negative. 11% positive +; Lachman test, 56% negative, 44% positive +; anterior drawer test, 89% +, 11% ++; GNRB test, 2.2 to 4.4 mm at 134 N, and 4.3 to 7.1 at 250 N. The diagnosis of partial ACL lesions, i.e., isolated tears of the AM or the PL bundle, requires accurate knowledge of knee anatomy and its biomechanics. In accordance with other authors our results showed that an arthroscopic examination of both bundles of the ligament as well as knee laxity evaluation under general anaesthesia are most essential for making the definite diagnosis in partial ACL tears. They also confirmed that, in isolated AM bundle lesions, ventral laxity is present more often particularly at a higher degree of knee flexion while, in PL bundle lesions, rotational laxity is more frequent and ranges from 0 to 30 degrees of knee flexion. To make the definite diagnosis of partial ACL tears, patient medical history, clinical knee examination including instability type and degree assessment under general anaesthesia and, most importantly, arthroscopic findings on both ACL bundles are necessary.

Does cortisol influence core executive functions? A meta-analysis of acute cortisol administration effects on working memory, inhibition, and set-shifting.

PubMed

Shields, Grant S; Bonner, Joseph C; Moons, Wesley G

2015-08-01

The hormone cortisol is often believed to play a pivotal role in the effects of stress on human cognition. This meta-analysis is an attempt to determine the effects of acute cortisol administration on core executive functions. Drawing on both rodent and stress literatures, we hypothesized that acute cortisol administration would impair working memory and set-shifting but enhance inhibition. Additionally, because cortisol is thought to exert different nongenomic (rapid) and genomic (slow) effects, we further hypothesized that the effects of cortisol would differ as a function of the delay between cortisol administration and cognitive testing. Although the overall analyses were nonsignificant, after separating the rapid, nongenomic effects of cortisol from the slower, genomic effects of cortisol, the rapid effects of cortisol enhanced response inhibition, g+ = 0.113, p=.016, but impaired working memory, g+ = -0.315, p=.008, although these effects reversed over time. Contrary to our hypotheses, there was no effect of cortisol administration on set-shifting. Thus, although we did not find support for the idea that increases in cortisol influence set-shifting, we found that acute increases in cortisol exert differential effects on working memory and inhibition over time. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Borderline Personality--An Adlerian Overview.

ERIC Educational Resources Information Center

Rattner, Leo

The person with a borderline personality is considered to be neither neurotic nor psychotic, but to exist somewhere in between these two diagnostic categories. Psychoanalytic theorists who have researched the phenomenon of the borderline personality have shifted their emphasis away from Freud's instinct psychology and toward an ego psychology…

Teacher Centers as a Social Phenomenon: An Anthropological Inquiry.

ERIC Educational Resources Information Center

Van Fleet, Alanson

1979-01-01

This article discusses the social and educational conditions that have supported the development of teacher centers, using a perspective from social anthropology, Malinowski's "functional" theory of institutions. Teacher centers are seen as a reflection of growing teacher power in a climate of shifting authority structures. (SJL)

Multi-Pivot Quicksort: an Experiment with Single, Dual, Triple, Quad, and Penta-Pivot Quicksort Algorithms in Python

NASA Astrophysics Data System (ADS)

Budiman, M. A.; Zamzami, E. M.; Rachmawati, D.

2017-03-01

Dual-pivot quicksort, which was proposed by Yaroslavsky, has been experimentally proven to be more efficient than the classical single-pivot quicksort under the Java Virtual Machine [6]. Moreover, Kushagara, López-Ortiz, and Munro [4] has shown that triple-pivot quicksort runs 7-8% faster than dual-pivot quicksort in C, mutatis mutandis. In this research, we implement and experiment with single, dual, triple, quad, and penta-pivot quicksort algorithms in Python. Our experimental results are as follows. Firstly, the quicksort with single pivot is the slowest among the five variants. Secondly, at least until five (penta) pivots are being used, it is proven that the more pivots are used in a quicksort algorithm, the faster its performance becomes. Thirdly, the increase of speed resulted by adding more pivots tends to decrease gradually.

Third-space fluid shift in elderly patients undergoing gastrointestinal surgery: Part II: nursing assessment.

PubMed

Wotton, Karen; Redden, Maurine

2002-08-01

Third-space fluid shift is the mobilisation of body fluid to a non-contributory space rendering it unavailable to the circulatory system. It is a recurrent clinical phenomenon requiring swift identification to minimise deleterious effects. Nurses experience difficulties however in its early identification, diagnosis and subsequent treatment because of the lack of consensual and consistent information regarding third-spacing. This article, part II, building on the previous article, explores the clinical validly and reliability of signs and symptoms of both phases of third-space fluid shift. In addition it reinforces the use multiple patient assessment cues if nurses are to differentiate between, and accurately respond to, the various causes of both hypovolaemia and hypervolaemia. It assists nurses to increase their knowledge and uderstanding of third-space fluid shift in patients undergoing gastrointestinal surgery.

Pivoting neuromuscular control and proprioception in females and males.

PubMed

Lee, Song Joo; Ren, Yupeng; Kang, Sang Hoon; Geiger, François; Zhang, Li-Qun

2015-04-01

Noncontact ACL injuries occur most commonly in pivoting sports and are much more frequent in females than in males. However, information on sex differences in proprioceptive acuity under weight-bearing and leg neuromuscular control in pivoting is scarce. The objective of this study was to investigate sex differences in pivoting neuromuscular control during strenuous stepping tasks and proprioceptive acuity under weight-bearing. 21 male and 22 female subjects were recruited to evaluate pivoting proprioceptive acuity under weight-bearing, and pivoting neuromuscular control (in terms of leg pivoting instability, stiffness, maximum internal and external pivoting angles, and entropy of time-to-peak EMG in lower limb muscles) during strenuous stepping tasks performed on a novel offaxis elliptical trainer. Compared to males, females had significantly lower proprioceptive acuity under weight-bearing in both internal and external pivoting directions, higher pivoting instability, larger maximum internal pivoting angle, lower leg pivoting stiffness, and higher entropy of time-to-peak EMG in the gastrocnemius muscles during strenuous stepping tasks with internal and external pivoting perturbations. Results of this study may help us better understand factors contributing to ACL injuries in females and males, develop training strategies to improve pivoting neuromuscular control and proprioceptive acuity, and potentially reduce ACL and lower-limb musculoskeletal injuries.

Lateral meniscus posterior root tear contributes to anterolateral rotational instability and meniscus extrusion in anterior cruciate ligament-injured patients.

PubMed

Minami, Takao; Muneta, Takeshi; Sekiya, Ichiro; Watanabe, Toshifumi; Mochizuki, Tomoyuki; Horie, Masafumi; Katagiri, Hiroki; Otabe, Koji; Ohara, Toshiyuki; Katakura, Mai; Koga, Hideyuki

2018-04-01

The purposes of this study were to investigate (1) meniscus status and clinical findings in anterior cruciate ligament (ACL)-injured patients to clarify associations between the meniscus posterior root tear (PRT) and knee instability, and (2) magnetic resonance imaging (MRI) findings of the PRT to clarify sensitivity and specificity of MRI and prevalence of meniscus extrusion. Three hundred and seventeen patients with primary ACL reconstruction were included. PRTs for both medial and lateral sides were confirmed by reviewing surgical records. Preoperative MRI was reviewed to evaluate sensitivity and specificity of the PRT and meniscus extrusion width (MEW). Clinical information regarding the number of giving-way episodes, preoperative KT-1000 measurements and preoperative pivot shift was also assessed. Thirty-nine patients had a lateral meniscus (LM) PRT, whereas only four patients had a medial meniscus PRT. One hundred and seventeen patients had no meniscus tear (control). Twenty-eight patients (71.8%) showed positive signs of the LMPRT based on at least one view of MR images, with the coronal view showing the highest sensitivity. MEW in the LMPRT group was significantly larger than that in the control group. The preoperative pivot shift test grade in the LMPRT group was significantly greater than that in the control group. There were no significant differences in other parameters. In ACL-injured patients, the LMPRT was associated with ALRI as well as with meniscus extrusion. The coronal view of MRI was useful in identifying the LMPRT, although its sensitivity was not high. Therefore, surgeons should prepare to repair PRTs at the time of ACL reconstruction regardless of MRI findings, and they should make every effort to repair the LMPRT. III.

The Influence of Knee Flexion Angle for Graft Fixation on Rotational Knee Stability During Anterior Cruciate Ligament Reconstruction: A Biomechanical Study.

PubMed

Debandi, Aníbal; Maeyama, Akira; Hoshino, Yuichi; Asai, Shigehiro; Goto, Bunsei; Smolinski, Patrick; Fu, Freddie H

2016-11-01

To evaluate the effect of knee flexion angle for hamstring graft fixation, full extension (FE), or 30°, on acceleration of the knee motion during pivot-shift testing after either anatomic or nonanatomic anterior cruciate ligament (ACL) reconstruction using triaxial accelerometry. Two types of ACL reconstructions (anatomic and nonanatomic) using 2 different angles of knee flexion during graft fixation (FE and 30°) were performed on 12 fresh-frozen human knees making 4 groups: anatomic-FE, anatomic-30°, nonanatomic-FE, and nonanatomic-30°. Manual pivot-shift testing was performed at ACL-intact, ACL-deficient, and ACL-reconstructed conditions. Three-dimensional acceleration of knee motion was recorded using a triaxial accelerometer. The anatomic-30° group showed the smallest overall magnitude of acceleration among the ACL-reconstructed groups (P = .0039). There were no significant differences among the anatomic-FE group, the nonanatomic-FE group, and the nonantomic-30° group (anatomic-FE vs nonanatomic-FE, P = .1093; anatomic-FE vs nonanatomic-30°, P = .8728; and nonanatomic-FE vs nonanatomic-30°, P = .1093). After ACL transection, acceleration was reduced by ACL reconstruction with the exception of the nonanatomic-FE group that did not show a significant difference when compared with the ACL-deficient (P = .4537). The anatomic ACL reconstruction with the graft fixed at 30° of knee flexion better restored rotational knee stability compared with FE. An ACL graft fixed with the knee at FE in anatomic position did not show a significant difference compared with the nonanatomic ACL reconstructions. Knee flexion angle at the time of graft fixation for ACL reconstruction can be considered to maximize the rotational knee stability. Copyright © 2016 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Functional Compensation of Motor Function in Pre-Symptomatic Huntington's Disease

ERIC Educational Resources Information Center

Kloppel, Stefan; Draganski, Bogdan; Siebner, Hartwig R.; Tabrizi, Sarah J.; Weiller, Cornelius; Frackowiak, Richard S. J.

2009-01-01

Involuntary choreiform movements are a clinical hallmark of Huntington's disease. Studies in clinically affected patients suggest a shift of motor activations to parietal cortices in response to progressive neurodegeneration. Here, we studied pre-symptomatic gene carriers to examine the compensatory mechanisms that underlie the phenomenon of…

Internal Organization to Serve Part-Time Student Needs.

ERIC Educational Resources Information Center

Massey, T. Benjamin

Two questions are addressed: (1) How can existing organizational structures and practices be developed where none have previously existed? The phenomenon of the adult postsecondary student is a fundamental demographic shift not initiated by the institutions but to which they must nonetheless respond. The organizational structure of the University…

Transforming School Health Education in Australia: Enhancing the Student Experience through Social Media

ERIC Educational Resources Information Center

Usher, Wayne

2012-01-01

Stemming from the social media (Web 2.0) phenomenon, this paper will discuss how such modern communication technologies have inadvertently caused a paradigm shift throughout the Australian school health education landscape. Furthermore, attention will be directed towards investigating the ensuing challenges, potentials and transformations…

Oriented shift and inverse of the daughter droplet due to the asymmetry of grand-daughter droplets of multiple emulsions in a symmetric flow field

NASA Astrophysics Data System (ADS)

Wang, Jingtao; Wang, Xiaoyong; Tai, Mo; Guan, Jing

2016-01-01

The rheological behaviors of multiple emulsions with an asymmetric internal structure in its third layer (grand-daughter droplets) under a modest extensional flow are investigated in this paper. The asymmetric structure will lead to the asymmetric circulation and pressure distribution inside the globule and eventually result in the oriented shift of its daughter droplet (in the second layer). The shift direction is affected not only by the structural asymmetry parameter As but also by some flow features including the capillary number Ca and viscosity ratio λ. Changes of these factors might cause the reverse of the shift direction, which are shown in three phase diagrams as a function of As, Ca, and λ. As the oriented shift of the daughter droplet would cause the oriented breakup of the multiple-emulsion globule, this phenomenon could be applied for the controlled release of the globule insertion by a hydrodynamic approach.

Molecular Mechanism of Wide Photoabsorption Spectral Shifts of Color Variants of Human Cellular Retinol Binding Protein II.

PubMed

Cheng, Cheng; Kamiya, Motoshi; Uchida, Yoshihiro; Hayashi, Shigehiko

2015-10-21

Color variants of human cellular retinol binding protein II (hCRBPII) created by protein engineering were recently shown to exhibit anomalously wide photoabsorption spectral shifts over ∼200 nm across the visible region. The remarkable phenomenon provides a unique opportunity to gain insight into the molecular basis of the color tuning of retinal binding proteins for understanding of color vision as well as for engineering of novel color variants of retinal binding photoreceptor proteins employed in optogenetics. Here, we report a theoretical investigation of the molecular mechanism underlying the anomalously wide spectral shifts of the color variants of hCRBPII. Computational modeling of the color variants with hybrid molecular simulations of free energy geometry optimization succeeded in reproducing the experimentally observed wide spectral shifts, and revealed that protein flexibility, through which the active site structure of the protein and bound water molecules is altered by remote mutations, plays a significant role in inducing the large spectral shifts.

A frequency standard via spectrum analysis and direct digital synthesis

NASA Astrophysics Data System (ADS)

Li, Dawei; Shi, Daiting; Hu, Ermeng; Wang, Yigen; Tian, Lu; Zhao, Jianye; Wang, Zhong

2014-11-01

We demonstrated a frequency standard based on a detuned coherent population beating phenomenon. In this phenomenon, the beat frequency of the radio frequency for laser modulation and the hyperfine splitting can be obtained by digital signal processing technology. After analyzing the spectrum of the beat frequency, the fluctuation information is obtained and applied to compensate for the frequency shift to generate the standard frequency by the digital synthesis method. Frequency instability of 2.6 × 1012 at 1000 s is observed in our preliminary experiment. By eliminating the phase-locking loop, the method will enable us to achieve a full-digital frequency standard with remarkable stability.

Low-frequency, self-sustained oscillations in inductively coupled plasmas used for optical pumping

DOE Office of Scientific and Technical Information (OSTI.GOV)

Coffer, J.; Encalada, N.; Huang, M.

We have investigated very low frequency, on the order of one hertz, self-pulsing in alkali-metal inductively-coupled plasmas (i.e., rf-discharge lamps). This self-pulsing has the potential to significantly vary signal-to-noise ratios and (via the ac-Stark shift) resonant frequencies in optically pumped atomic clocks and magnetometers (e.g., the atomic clocks now flying on GPS and Galileo global navigation system satellites). The phenomenon arises from a nonlinear interaction between the atomic physics of radiation trapping and the plasma's electrical nature. To explain the effect, we have developed an evaporation/condensation theory (EC theory) of the self-pulsing phenomenon.

A Long-Term Scientific Survey of the Hessdalen Phenomenon

NASA Astrophysics Data System (ADS)

Teodorani, M.

2004-06-01

The balls of light which appear in the Hessdalen valley in Norway are exemplary of anomalous atmospheric luminous phenomena that occur frequently at some locations on Earth. The recurrence of the phenomenon and the existence of an instrumented observation station makes this area an ideal research site. The apparent correlation of luminous phenomena with magnetic perturbations, radio emission, and radar tracks, found by Norwegian researchers, led some Italian physicists and engineers of the EMBLA Project to reanalyze the Norwegian data. The second step was three explorative, instrumented, field-study expeditions. The behavior of the phenomenon was monitored with optical, radio, and radar techniques. The global picture of the phenomenon obtained so far shows that the phenomenon's radiant power varies, reaching values up to 19 kW. These changes are caused by sudden surface variations of the illuminated area owing to the appearance of clusters of light balls that behave in a thermally self-regulated way. Apparent characteristics consistent with a solid are strongly suspected from the study of distributions of radiant power. Other anomalous characteristics include the capability to eject smaller light balls, some unidentified frequency shift in the VLF range, and possible deposition of metallic particles. A self-consistent definitive theory of the phenomenon's nature and origin in all its aspects cannot be constructed yet quantitatively, but some of the observations can be explained by an electrochemical model for the ball-lightning phenomenon. The importance is stressed of using more sophisticated instrumentation in the future.

Manipulation of wavefront using helical metamaterials.

PubMed

Yang, Zhenyu; Wang, Zhaokun; Tao, Huan; Zhao, Ming

2016-08-08

Helical metamaterials, a kind of 3-dimensional structure, has relatively strong coupling effect among the helical nano-wires. Therefore, it is expected to be a good candidate for generating phase shift and controlling wavefront with high efficiency. In this paper, using the finite-difference time-domain (FDTD) method, we studied the phase shift properties in the helical metamaterials. It is found that the phase shift occurs for both transmitted and reflected light waves. And the maximum of reflection coefficients can reach over 60%. In addition, the phase shift (φ) is dispersionless in the range of 600 nm to 860 nm, that is, it is only dominated by the initial angle (θ) of the helix. The relationship between them is φ = ± 2θ. Using Jones calculus we give a further explanation for these properties. Finally, by arranging the helixes in an array with a constant phase gradient, the phenomenon of anomalous refraction was also observed in a broad wavelength range.

Causes and projections of abrupt climate-driven ecosystem shifts in the North Atlantic.

PubMed

Beaugrand, Grégory; Edwards, Martin; Brander, Keith; Luczak, Christophe; Ibanez, Frederic

2008-11-01

Warming of the global climate is now unequivocal and its impact on Earth' functional units has become more apparent. Here, we show that marine ecosystems are not equally sensitive to climate change and reveal a critical thermal boundary where a small increase in temperature triggers abrupt ecosystem shifts seen across multiple trophic levels. This large-scale boundary is located in regions where abrupt ecosystem shifts have been reported in the North Atlantic sector and thereby allows us to link these shifts by a global common phenomenon. We show that these changes alter the biodiversity and carrying capacity of ecosystems and may, combined with fishing, precipitate the reduction of some stocks of Atlantic cod already severely impacted by exploitation. These findings offer a way to anticipate major ecosystem changes and to propose adaptive strategies for marine exploited resources such as cod in order to minimize social and economic consequences.

Insights into human evolution from ancient and contemporary microbiome studies

PubMed Central

Schnorr, Stephanie L; Sankaranarayanan, Krithivasan; Lewis, Cecil M; Warinner, Christina

2017-01-01

Over the past decade, human microbiome research has energized the study of human evolution through a complete shift in our understanding of what it means to be human. The microbiome plays a pivotal role in human biology, performing key functions in digestion, mood and behavior, development and immunity, and a range of acute and chronic diseases. It is therefore critical to understand its evolution and changing ecology through time. Here we review recent findings on the microbiota of diverse human populations, non-human primates, and past human populations and discuss the implications of this research in formulating a deeper evolutionary understanding of the human holobiont. PMID:27507098

Molecular identification of Taenia serialis coenurosis in a wild Ethiopian gelada (Theropithecus gelada).

PubMed

Schneider-Crease, India A; Snyder-Mackler, Noah; Jarvey, Julie C; Bergman, Thore J

2013-11-15

Since morphological identification of a larval Taeniid in geladas (Theropithecus gelada) has produced inconsistent results, genetic information is pivotal for species identification. Nuclear and mitochondrial DNA from a coenurus in a wild gelada were compared to published sequences from multiple Taeniid species, confirming the identification of this parasite as Taenia serialis. A demographic analysis finds age to be a strong predictor of coenuri. Tapeworms rarely employ primates as intermediate hosts, and the presence of T. serialis in a wild gelada population may indicate a substantial ecological shift in this parasite's life cycle. Copyright © 2013 Elsevier B.V. All rights reserved.

Druggable pockets and binding site centric chemical space: a paradigm shift in drug discovery.

PubMed

Pérot, Stéphanie; Sperandio, Olivier; Miteva, Maria A; Camproux, Anne-Claude; Villoutreix, Bruno O

2010-08-01

Detection, comparison and analyses of binding pockets are pivotal to structure-based drug design endeavors, from hit identification, screening of exosites and de-orphanization of protein functions to the anticipation of specific and non-specific binding to off- and anti-targets. Here, we analyze protein-ligand complexes and discuss methods that assist binding site identification, prediction of druggability and binding site comparison. The full potential of pockets is yet to be harnessed, and we envision that better understanding of the pocket space will have far-reaching implications in the field of drug discovery, such as the design of pocket-specific compound libraries and scoring functions.

Welding Experiments of Aluminum Alloy by Space GHTA Welding in the ISS Orbital Pressure

NASA Astrophysics Data System (ADS)

Suita, Yoshikazu; Takai, Daisuke; Sugiyama, Satoshi; Terajima, Noboru; Tsukuda, Yoshiyuki; Fujisawa, Shoichiro; Imagawa, Kichiro

As a feasible welding method in space, the authors have previously proposed the space GHTA (Gas Hollow Tungsten Arc) welding process. The space GHTA welding with high frequency power source for the arc starting may cause the electro-magnetic noise problems of computer equipments placed on the ISS. Therefore, in this paper the welding experiments of aluminum alloy by the space GHTA welding with DC high voltage power source for the arc starting was carried out in the ISS orbital pressure 10-5Pa. It is made clear that there is the shifting phenomenon in which the spark discharge changes to the glow or arc discharge at starting phenomenon of the space GHTA welding in high vacuum condition, and the features of those starting phenomenon are demonstrated. And the space GHTA welding with DC high voltage power source can be used for welding in the ISS orbital pressure.

[Psychophysiology of suicide in prison: a contribution in terms of prevention].

PubMed

Anselmi, Nino; Alliani, Daniela; Ghini, Francesca

2014-01-01

Suicide in detention environment is a phenomenon that affects both prisoners and operators, especially prison service. Currently, in terms of suicide prevention, the interest is shifting from an etiology essentially endogenous to exogenous factors, seeing as the criticality of system has its origin in the lack of knowledge of the "detained person". This work neglects statistics and detection models to look at all those behaviors that are part of suicide, although the suicidal act is not genuine. This view allows to identify areas of risk and it is not just for have a look over "the death event". Aware that no definition is enough to shed light on this phenomenon where subjectivity is elusive, we must always bear in mind the behaviors that precede it and exogenous and endogenous factors. To better understand the phenomenon of suicide in prison it is necessary to be aware of the action that a "totalizing institution" has on the individual.

Sagittal focusing Laue monochromator

DOEpatents

Zhong,; Zhong, Hanson [Stony Brook, NY; Jonathan, Hastings [Wading River, NY; Jerome, Kao [Stanford, CA; Chi-Chang, Lenhard [Setauket, NY; Anthony, Siddons [Medford, NY; David Peter, Zhong [Cutchogue, NY; Hui, [Coram, NY

2009-03-24

An x-ray focusing device generally includes a slide pivotable about a pivot point defined at a forward end thereof, a rail unit fixed with respect to the pivotable slide, a forward crystal for focusing x-rays disposed at the forward end of the pivotable slide and a rearward crystal for focusing x-rays movably coupled to the pivotable slide and the fixed rail unit at a distance rearward from the forward crystal. The forward and rearward crystals define reciprocal angles of incidence with respect to the pivot point, wherein pivoting of the slide about the pivot point changes the incidence angles of the forward and rearward crystals while simultaneously changing the distance between the forward and rearward crystals.

Status of Tamil Language in Singapore: An Analysis of Family Domain

ERIC Educational Resources Information Center

Kadakara, Shanmugam

2015-01-01

This paper addresses the phenomenon of Language Maintenance and Language Shift through a qualitative study of Tamil language in the family domain in Singapore. The influence of Singapore's bilingual policy and the institutional support offered for maintenance of Tamil language provide the context in which the central research problem of the status…

Chasing the Butterfly Effect: Informal Language Learning Online as a Complex System

ERIC Educational Resources Information Center

Godwin-Jones, Robert

2018-01-01

Evidence is accumulating that a major shift is underway in the ways that second language (L2) development is taking place. Increasingly, especially among young people, that process is occurring outside of institutional settings, predominately through the use of online networks and media. That phenomenon has been particularly noticed for learners…

An Ontological Perspective on the Development of Home-School Partnership Relationships with Indigenous Communities

ERIC Educational Resources Information Center

Hindle, Rawiri; Hynds, Anne; Averill, Robin; Meyer, Luanna; Faircloth, Susan

2017-01-01

We propose the use of an ontological perspective to shift current thinking about the phenomenon of home/school partnerships, particularly through an examination of school leaders (leadership team)--community relationships that seek to better serve Indigenous students and their communities. We reanalysed focus group interviews of indigenous Maori…

Teaching Shrimps Self-Defense to Fight Infections.

PubMed

Norouzitallab, Parisa; Baruah, Kartik; Vanrompay, Daisy; Bossier, Peter

2018-06-15

A paradigm shift in our understanding of shrimp immunity offers the potential to develop novel disease-control strategies. We summarize cutting-edge findings on the phenomenon of trained immunity in shrimps and discuss how it may contribute to new avenues for controlling disease in these aquaculturally important animals. Copyright © 2018 Elsevier Ltd. All rights reserved.

Before Writing: Rethinking the Paths to Literacy.

ERIC Educational Resources Information Center

Kress, Gunther

This book calls for a radical reappraisal of the phenomenon of literacy, and hence for a profound shift in educational practice. Through close attention to the multitude of objects which children constantly produce (drawings, cuttings-out, writings, collages), the book suggests a set of principles that reveal the underlying coherence of children's…

World Population Ageing, 1950-2050.

ERIC Educational Resources Information Center

United Nations, New York, NY. Dept. of Economic and Social Affairs.

Population aging was one of the most distinctive events of the 20th century and will remain important throughout the 21st century. Initially, a phenomenon of more developed countries, the process has recently become apparent in much of the developing world as well. The shift in age structure associated with population aging has a profound impact…

Impact on the world poultry industry of the global shift to biofuels.

PubMed

Aho, P

2007-11-01

The shift to biofuels is a worldwide phenomenon, but the most notable recent development has been the rapid increase in the production of ethanol in the United States. Ethanol production in the United States enjoys a substantial subsidy, tariff protection, and mandated use. The consequence of increasing biofuels production is to raise the cost of feed and food worldwide. Those that suffer from this policy include all consumers of food, most notably the urban poor of developing countries. Those that benefit from the policy are farmers everywhere, including farmers in developing countries.

How children create their space for play?

NASA Astrophysics Data System (ADS)

Bobby Saragih, John Freddy; Tedja, Michael

2017-12-01

The phenomenon of children’s play in the urban area in Indonesia has experienced a shift; they are often seen playing in the street, sidewalk and drainage. This shift raises the question: what is interesting about the space, so that they use it as a space for play? There are metaphysical based of space that can be grasped by children senses when they utilize that particular space. This qualitative research based involving children aged between 6 and 12 years found that spatial manifestation; such as freedom, excitement and surprise are the main motivations when they use the space as their playing area.

Temperature Dependence of the Thermal Conductivity of Single Wall Carbon Nanotubes

NASA Technical Reports Server (NTRS)

Osman, Mohamed A.; Srivastava, Deepak

2000-01-01

The thermal conductivity of several single wall carbon nanotubes (CNT) has been calculated over a temperature range of 100-500 K using molecular dynamics simulations with Tersoff-Brenner potential for C-C interactions. In all cases, starting from similar values at 100K, thermal conductivities show a peaking behavior before falling off at higher temperatures. The peak position shifts to higher temperatures for nanotubes of larger diameter, and no significant dependence on the tube chirality is observed. It is shown that this phenomenon is due to onset of Umklapp scattering, which shifts to higher temperatures for nanotubes of larger diameter.

COMMENT: Comment on 'Particle size dependent exchange bias and cluster-glass states in LaMn0.7Fe0.3O3 '

NASA Astrophysics Data System (ADS)

Geshev, J.

2009-02-01

Thakur et al (2008 J. Phys.: Condens. Matter 20 195215) have recently reported magnetization hysteresis loops shifted along the field axis of the cluster-glass compound LaMn0.7Fe0.3O3, attributed there to exchange bias induced at ferromagnetic/spin-glass-like interfaces. The present comment affirms that their results are insufficient for assigning the phenomenon solely to exchange bias since the corresponding field shift, if any, cannot be separated from that of a minor hysteresis loop of a ferromagnet, naturally displaced from the origin.

The Frequency of Fitness Peak Shifts Is Increased at Expanding Range Margins Due to Mutation Surfing

PubMed Central

Burton, Olivia J.; Travis, Justin M. J.

2008-01-01

Dynamic species' ranges, those that are either invasive or shifting in response to environmental change, are the focus of much recent interest in ecology, evolution, and genetics. Understanding how range expansions can shape evolutionary trajectories requires the consideration of nonneutral variability and genetic architecture, yet the majority of empirical and theoretical work to date has explored patterns of neutral variability. Here we use forward computer simulations of population growth, dispersal, and mutation to explore how range-shifting dynamics can influence evolution on rugged fitness landscapes. We employ a two-locus model, incorporating sign epistasis, and find that there is an increased likelihood of fitness peak shifts during a period of range expansion. Maladapted valley genotypes can accumulate at an expanding range front through a phenomenon called mutation surfing, which increases the likelihood that a mutation leading to a higher peak will occur. Our results indicate that most peak shifts occur close to the expanding front. We also demonstrate that periods of range shifting are especially important for peak shifting in species with narrow geographic distributions. Our results imply that trajectories on rugged fitness landscapes can be modified substantially when ranges are dynamic. PMID:18505864

Clinical diagnosis of partial or complete anterior cruciate ligament tears using patients' history elements and physical examination tests

PubMed Central

Fallaha, Michel; Belzile, Sylvain; Martel-Pelletier, Johanne; Pelletier, Jean-Pierre; Feldman, Debbie; Sylvestre, Marie-Pierre; Vendittoli, Pascal-André; Desmeules, François

2018-01-01

Objective To assess the diagnostic validity of clusters combining history elements and physical examination tests to diagnose partial or complete anterior cruciate ligament (ACL) tears. Design Prospective diagnostic study. Settings Orthopaedic clinics (n = 2), family medicine clinics (n = 2) and community-dwelling. Participants Consecutive patients with a knee complaint (n = 279) and consulting one of the participating orthopaedic surgeons (n = 3) or sport medicine physicians (n = 2). Interventions Not applicable. Main outcome measures History elements and physical examination tests performed independently were compared to the reference standard: an expert physicians’ composite diagnosis including history elements, physical tests and confirmatory magnetic resonance imaging. Penalized logistic regression (LASSO) was used to identify history elements and physical examination tests associated with the diagnosis of ACL tear and recursive partitioning was used to develop diagnostic clusters. Diagnostic accuracy measures including sensitivity (Se), specificity (Sp), predictive values and positive and negative likelihood ratios (LR+/-) with associated 95% confidence intervals (CI) were calculated. Results Forty-three individuals received a diagnosis of partial or complete ACL tear (15.4% of total cohort). The Lachman test alone was able to diagnose partial or complete ACL tears (LR+: 38.4; 95%CI: 16.0–92.5). Combining a history of trauma during a pivot with a “popping” sensation also reached a high diagnostic validity for partial or complete tears (LR+: 9.8; 95%CI: 5.6–17.3). Combining a history of trauma during a pivot, immediate effusion after trauma and a positive Lachman test was able to identify individuals with a complete ACL tear (LR+: 17.5; 95%CI: 9.8–31.5). Finally, combining a negative history of pivot or a negative popping sensation during trauma with a negative Lachman or pivot shift test was able to exclude both partial or complete ACL tears (LR-: 0.08; 95%CI: 0.03–0.24). Conclusion Diagnostic clusters combining history elements and physical examination tests can support the differential diagnosis of ACL tears compared to various knee disorders. PMID:29894492

Hemispheric asymmetry in coronal hole evolution: Cause of the bashful ballerina?

NASA Astrophysics Data System (ADS)

Mursula, K.; Tlatov, A.; Virtanen, I.

2012-12-01

The magnetic hemisphere prevalent in the solar northern hemisphere has been shown to cover a larger area than in the south for about three years in the declining phase of several solar cycles. Correspondingly, the average field intensity is weaker in the northern hemisphere and the heliospheric current sheet (HCS) is shifted southward at these times. This phenomenon, now called the bashful ballerina, has been verified using several databases and methods, including the in situ observations of the heliospheric magnetic field (HMF) at 1 AU by the OMNI data base, at about 2 AU by the Ulysses probe, and at different radial distances by the Voyager 1 and 2 and Pioneer 10 and 11 probes. The Ulysses observations show that the mean southward shift of the HCS was about 2 degrees in the declining phase of both cycle 22 and cycle 23, although the polar strengths were very different between the two cycles. The HMF observations by the Voyager and Pioneer probes show a very consistent structure of HMF sectors and HCS location in the entire heliosphere, and even beyond the termination shock. Moreover, they suggest a systematic difference in the development of northern and southern polar coronal holes. While the northern coronal holes developed very systematically during all the four solar minima since mid-1970s, the evolution of southern coronal holes was less systematic and delayed with respect to the northern hemisphere. This delay in the evolution of southern coronal holes leads to a larger extent of northern coronal holes and a southward shift of the heliospheric current sheet (the bashful ballerina phenomenon) for a few years in the declining phase of the solar cycle. Here we study direct observations of solar coronal holes and verify this difference in the evolution of coronal holes between the two solar hemispheres, which explains the bashful ballerina phenomenon.

Racial entanglements and sociological confusions: repudiating the rehabilitation of integration.

PubMed

Valluvan, Sivamohan

2018-06-01

In line with the broader nationalist advances currently remaking the Western political landscape, the concept of integration has witnessed a marked rehabilitation. Whilst many influential critiques of the sociology of integration are already available, this article contests the concept's renewed purchase through addressing its own internal incoherence. Based on research in Stockholm, this critique concerns the relationship between ethnic identity and cultural integration. It will be argued that integration and the production of difference are intertwined, entangled dualities, and far from being a benign entanglement, this duality is premised on the force and reach of everyday civic racisms. Of pivotal and unique analytical significance here is the observation that racism should not only be considered an exogenous process that impedes integration, but as a multifaceted phenomenon folded into integration. © London School of Economics and Political Science 2017.

Blocking the mineralocorticoid receptor in humans prevents the stress-induced enhancement of centromedial amygdala connectivity with the dorsal striatum.

PubMed

Vogel, Susanne; Klumpers, Floris; Krugers, Harm J; Fang, Zhou; Oplaat, Krista T; Oitzl, Melly S; Joëls, Marian; Fernández, Guillén

2015-03-01

Two research lines argue for rapid stress-induced reallocations of neural network activity involving the amygdala. One focuses on the role of norepinephrine (NE) in mediating a shift towards the salience network and improving vigilance processing, whereas the other focuses on the role of cortisol in enhancing automatic, habitual responses. It has been suggested that the mineralocorticoid receptor (MR) is critical in shifting towards habitual responses, which are supported by the dorsal striatum. However, until now it remained unclear whether these two reallocations of neural recourses might be part of the same phenomenon and develop immediately after stress onset. We combined methods used in both approaches and hypothesized specifically that stress would lead to rapidly enhanced involvement of the striatum as assessed by amygala-striatal connectivity. Furthermore, we tested the hypothesis that this shift depends on cortisol interacting with the MR, by using a randomized, placebo-controlled, full-factorial, between-subjects design with the factors stress and MR-blockade (spironolactone). We investigated 101 young, healthy men using functional magnetic resonance imaging after stress induction, which led to increased negative mood, heart rate, and cortisol levels. We confirmed our hypothesis by revealing a stress-by-MR-blockade interaction on the functional connectivity between the centromedial amygdala (CMA) and the dorsal striatum. Stress rapidly enhanced CMA-striatal connectivity and this effect was correlated with the stress-induced cortisol response, but required MR availability. This finding might suggest that the stress-induced shift described by distinct research lines might capture different aspects of the same phenomenon, ie, a reallocation of neural resources coordinated by both NE and cortisol.

The wide skirt of the bashful ballerina: Hemispheric asymmetry of the heliospheric magnetic field in the inner and outer heliosphere

NASA Astrophysics Data System (ADS)

Mursula, K.; Virtanen, I. I.

2012-08-01

We reanalyze the observations of the heliospheric magnetic field (HMF) made by the Pioneer 10 and 11 and Voyager 1 and 2 heliospheric probes since 1972, and calculate the HMF sector occurrence ratios and tangential component strengths in the different regions of the heliosphere. Observations at the distant probes and at 1 AU show a very consistent picture of the HMF sector structure in the entire heliosphere, and even beyond the termination shock. HMF observations by the probes also support the southward shift of the heliospheric current sheet (the bashful ballerina phenomenon), which is observed earlier at 1-2 AU by the Ulysses probe and Earth-orbiting satellites, and verify the HCS shift over a wide range of radial distances until the distant heliosphere. Pioneer 11 and Voyager 1 show that the development of northern polar coronal holes was very systematic and active during all the four solar minima since mid-1970s, while Voyager 2 observations show a less systematic and delayed development of southern coronal holes in 1980s, 1990s and 2000s. This delay in the evolution of southern coronal holes with respect to the rapid and systematic evolution of northern coronal holes leads to a larger extent of northern coronal holes and the southward shift of the HCS for a few years in the late declining phase of each solar cycle. Although evidence for the connection between the different evolution of polar coronal holes and the bashful ballerina phenomenon is obtained here only for three solar cycles, this may be a common pattern for solar coronal hole evolution since the southward shift of the HCS has occurred at least since solar cycle 16.

Long-Term Experimental Acidification Drives Watershed Scale Shift in Dissolved Organic Matter Composition and Flux

Treesearch

Michael D. SanClements; Ivan J. Fernandez; Robert H. Lee; Joshua A. Roberti; Mary Beth Adams; Garret A. Rue; Diane M. McKnight

2018-01-01

Over the last several decades dissolved organic carbon concentrations (DOC) in surface waters have increased throughout much of the northern hemisphere. Several hypotheses have been proposed regarding the drivers of this phenomenon including decreased sulfur (S) deposition working via an acidity- change mechanism. Using fluorescence spectroscopy and data from two long-...

Analysis of Students' Aptitude to Provide Meaning to Images that Represent Cellular Components at the Molecular Level

ERIC Educational Resources Information Center

Dahmani, Hassen-Reda; Schneeberger, Patricia; Kramer, IJsbrand M.

2009-01-01

The number of experimentally derived structures of cellular components is rapidly expanding, and this phenomenon is accompanied by the development of a new semiotic system for teaching. The infographic approach is shifting from a schematic toward a more realistic representation of cellular components. By realistic we mean artist-prepared or…

What Have We Learnt about Mobile LifeLong Learning (mLLL)?

ERIC Educational Resources Information Center

Seta, Luciano; Kukulska-Hulme, Agnes; Arrigo, Marco

2014-01-01

Mobile technologies are becoming ubiquitous in education, yet the wider implications of this phenomenon are not well understood. The paper discusses how mobile lifelong learning (mLLL) may be defined, and the challenges of forging a suitable definition in an ever-shifting technological and socio-economic landscape. mLLL appears as a ubiquitous…

Can Small Lesions Induce Language Reorganization as Large Lesions Do?

ERIC Educational Resources Information Center

Maestu, Fernando; Saldana, Cristobal; Amo, Carlos; Gonzalez-Hidalgo, Mercedes; Fernandez, Alberto; Fernandez, Santiago; Mata, Pedro; Papanicolaou, Andrew; Ortiz, Tomas

2004-01-01

Shift of the cortical mechanisms of language from the usually dominant left to the non-dominant right hemisphere has been demonstrated in the presence of large brain lesions. Here, we report a similar phenomenon in a patient with a cavernoma over the anterolateral superior temporal gyrus associated with epilepsy. Language mapping was performed by…

Internal optical bistability of quasi-two-dimensional semiconductor nanoheterostructures

NASA Astrophysics Data System (ADS)

Derevyanchuk, Oleksandr V.; Kramar, Natalia K.; Kramar, Valeriy M.

2018-01-01

We represent the results of numerical computations of the frequency and temperature domains of possible realization of internal optical bistability in flat quasi-two-dimensional semiconductor nanoheterostructures with a single quantum well (i.e., nanofilms). Particular computations have been made for a nanofilm of layered semiconductor PbI2 embedded in dielectric medium, i.e. ethylene-methacrylic acid (E-MAA) copolymer. It is shown that an increase in the nanofilm's thickness leads to a long-wave shift of the frequency range of the manifestation the phenomenon of bistability, to increase the size of the hysteresis loop, as well as to the expansion of the temperature interval at which the realization of this phenomenon is possible.

Carrier-dependent magnetic anisotropy of cobalt doped titanium dioxide

PubMed Central

Shao, Bin; Feng, Min; Zuo, Xu

2014-01-01

Using first-principles calculations, we predict that the magnetic anisotropy energy of Co-doped TiO2 sensitively depends on carrier accumulation. This magnetoelectric phenomenon provides a potential route to a direct manipulation of the magnetization direction in diluted magnetic semiconductor by external electric-fields. We calculate the band structures and reveal the origin of the carrier-dependent magnetic anisotropy energy in k-space. It is shown that the carrier accumulation shifts the Fermi energy, and consequently, regulates the competing contributions to the magnetic anisotropy energy. The calculations provide an insight to understanding this magnetoelectric phenomenon, and a straightforward way to search prospective materials for electrically controllable spin direction of carriers. PMID:25510846

Fluid Transport in Porous Media probed by Relaxation-Exchange NMR

NASA Astrophysics Data System (ADS)

Olaru, A. M.; Kowalski, J.; Sethi, V.; Blümich, B.

2011-12-01

The characterization of fluid transport in porous media represents a matter of high interest in fields like the construction industry, oil exploitation, and soil science. Moisture migration or flow at low rates, such as those occurring in soil during rain are difficult to characterize by classical high-field NMR velocimetry due to the dedicated hardware and elaborate techniques required for adequate signal encoding. The necessity of field studies raises additional technical problems, which can be solved only by the use of portable low-field NMR instruments. In this work we extend the use of low-field relaxation exchange experiments from the study of diffusive transport to that of advection. Relaxation exchange experiments were performed using a home-built Halbach magnet on model porous systems with controlled pore-size distributions and on natural porous systems (quartz sand with a broad pore-size distribution) exposed to unidirectional flow. Different flow rates leave distinctive marks on the exchange maps obtained by inverse Laplace transformation of the time domain results, due to the superposition of exchange, diffusion and inflow/outflow in multiple relaxation sites of the liquids in the porous media. In the case of slow velocities there is no loss of signal due to outflow, and the relaxation-exchange effects prevail, leading to a tilt of the diagonal distribution around a pivot point with increasing mixing time. The tilt suggests an asymmetry in the exchange between relaxation sites of large and small decay rates. Another observed phenomenon is the presence of a bigger number of exchange cross-peaks compared to the exchange maps obtained for the same systems in zero-flow conditions. We assume that this is due to enhanced exchange caused by the superposition of flow. For high velocities the outflow effects dominate and the relaxation-time distribution collapses towards lower values of the average relaxation times. In both cases the pore-size distribution has a strong effect on the results, the asymmetries being more obvious in the natural porous systems than in the glass bead packs used as models, while the enhanced exchange phenomenon appears predominantly in the maps obtained on the model systems. This is probably due to diffusion occurring in the presence of different internal field gradients. Shifts and tilts in the exchange maps can be simulated by solving the relaxation site-averaged Bloch-Torrey system forward in time and assuming an asymmetric closure for the transport, which might be realistic for preferential flow phenomena or for pore-size distributions with two or more clearly distinct pore size classes. When comparing the simulations results with the experimental data we observed a correspondence of signal collapse and translation towards lower relaxation times. The asymmetries could be qualitatively reproduced by making further assumptions on the pore structure, but further work is required to characterize and model the physical phenomenon behind. The results obtained reveal the possibility of characterizing advective fluid transport in porous systems by simple correlation experiments performed with inexpensive and mobile hardware.

On non-local energy transfer via zonal flow in the Dimits shift

NASA Astrophysics Data System (ADS)

St-Onge, Denis A.

2017-10-01

The two-dimensional Terry-Horton equation is shown to exhibit the Dimits shift when suitably modified to capture both the nonlinear enhancement of zonal/drift-wave interactions and the existence of residual Rosenbluth-Hinton states. This phenomenon persists through numerous simplifications of the equation, including a quasilinear approximation as well as a four-mode truncation. It is shown that the use of an appropriate adiabatic electron response, for which the electrons are not affected by the flux-averaged potential, results in an nonlinearity that can efficiently transfer energy non-locally to length scales of the order of the sound radius. The size of the shift for the nonlinear system is heuristically calculated and found to be in excellent agreement with numerical solutions. The existence of the Dimits shift for this system is then understood as an ability of the unstable primary modes to efficiently couple to stable modes at smaller scales, and the shift ends when these stable modes eventually destabilize as the density gradient is increased. This non-local mechanism of energy transfer is argued to be generically important even for more physically complete systems.

Retrieval-Induced vs. Context-Induced Forgetting: Does Retrieval-Induced Forgetting Depend on Context Shifts?

PubMed Central

Soares, Julia S.; Polack, Cody W.; Miller, Ralph R.

2015-01-01

Retrieval-induced forgetting (RIF) is the observation that retrieval of target information causes forgetting of related non-target information. A number of accounts of this phenomenon have been proposed, including a context-shift based account (Jonker, Seli, & Macleod, 2013). This account proposes that RIF occurs due to the context shift from study to retrieval practice, provided there is little context shift between retrieval practice and test phases. We tested both claims put forth by this context account. In Experiment 1, we degraded the context shift between study and retrieval practice by implementing a generative study condition that was highly similar to retrieval practice. We observed no degradation of RIF for these generated exemplars relative to a conventional study control. In Experiment 2, we conceptually replicated the finding of RIF following generative study, and tested whether context differences between each of the three phases affected the size of RIF. Our findings were again contrary to the predictions of the context account. Conjointly, the two experiments refute arguments about the potential inadequacy of our context shifts that could be used to explain either result alone. Overall, our results are most consistent with an inhibitory account of RIF (e.g., Anderson, 2003). PMID:26389628

Renal Sympathetic Denervation – A Review of Applications in Current Practice

PubMed Central

Kapil, Vikas; Jain, Ajay K

2014-01-01

Resistant hypertension is associated with high morbidity and mortality despite numerous pharmacological strategies. A wealth of preclinical and clinical data have demonstrated that resistant hypertension is associated with elevated renal and central sympathetic tone. The development of interventional therapies to modulate the sympathetic nervous system potentially represents a paradigm shift in the strategy for blood pressure control in this subset of patients. Initial first-in-man and pivotal, randomised controlled trials of endovascular, radio-frequency renal sympathetic denervation have spawned numerous iterations of similar technology, as well as many novel concepts for achieving effective renal sympatholysis. This review details the current knowledge of these devices and the evidence base behind each technology. PMID:29588780

Redesigning the exploitation of wheat genetic resources.

PubMed

Longin, C Friedrich H; Reif, Jochen C

2014-10-01

More than half a million wheat genetic resources are resting in gene banks worldwide. Unlocking their hidden favorable genetic diversity for breeding is pivotal for enhancing grain yield potential, and averting future food shortages. Here, we propose exploiting recent advances in hybrid wheat technology to uncover the masked breeding values of wheat genetic resources. The gathered phenotypic information will enable a targeted choice of accessions with high value for pre-breeding among this plethora of genetic resources. We intend to provoke a paradigm shift in pre-breeding strategies for grain yield, moving away from allele mining toward genome-wide selection to bridge the yield gap between genetic resources and elite breeding pools. Copyright © 2014 Elsevier Ltd. All rights reserved.

The role of the corporate nurse executive: providing balance and perspective for patient care and the corporate structure.

PubMed

Ameigh, A Y

1996-01-01

The nurse executive at the corporate level is in a pivotal position to provide balance between the provision of integrated patient care and success of the corporate mission. In this role, the nurse executive shifts the spotlight from a solely nursing perspective to the systems approach in support of patient care. The response that follows is often a redoubling of the efforts of health care providers to render more efficient and cohesive care to patients. In the end, success is an outgrowth of strong teamwork combined with the ability of the executive to connect the corporate business strategy with the provision of patient care wherever it is delivered.

Bioinformatics Approaches for Fetal DNA Fraction Estimation in Noninvasive Prenatal Testing

PubMed Central

Peng, Xianlu Laura; Jiang, Peiyong

2017-01-01

The discovery of cell-free fetal DNA molecules in plasma of pregnant women has created a paradigm shift in noninvasive prenatal testing (NIPT). Circulating cell-free DNA in maternal plasma has been increasingly recognized as an important proxy to detect fetal abnormalities in a noninvasive manner. A variety of approaches for NIPT using next-generation sequencing have been developed, which have been rapidly transforming clinical practices nowadays. In such approaches, the fetal DNA fraction is a pivotal parameter governing the overall performance and guaranteeing the proper clinical interpretation of testing results. In this review, we describe the current bioinformatics approaches developed for estimating the fetal DNA fraction and discuss their pros and cons. PMID:28230760

Bioinformatics Approaches for Fetal DNA Fraction Estimation in Noninvasive Prenatal Testing.

PubMed

Peng, Xianlu Laura; Jiang, Peiyong

2017-02-20

The discovery of cell-free fetal DNA molecules in plasma of pregnant women has created a paradigm shift in noninvasive prenatal testing (NIPT). Circulating cell-free DNA in maternal plasma has been increasingly recognized as an important proxy to detect fetal abnormalities in a noninvasive manner. A variety of approaches for NIPT using next-generation sequencing have been developed, which have been rapidly transforming clinical practices nowadays. In such approaches, the fetal DNA fraction is a pivotal parameter governing the overall performance and guaranteeing the proper clinical interpretation of testing results. In this review, we describe the current bioinformatics approaches developed for estimating the fetal DNA fraction and discuss their pros and cons.

Cluster glass induced exchange biaslike effect in the perovskite cobaltites

NASA Astrophysics Data System (ADS)

Luo, Wanju; Wang, Fangwei

2007-04-01

Exchange biaslike phenomenon is observed in the Ba doped perovskite polycrystalline LaCoO3. The magnetic hysteresis loop shifts in both horizontal and vertical directions at 5K when the samples are cooled down to 5K in a magnetic field. The nature of this magnetic anisotropy is ascribed to the freezing properties of the local anisotropy in the cluster glass system. The magnetic shifts in horizontal and vertical directions can be derived directly under the principle that the spins of a cluster are frozen in random orientations and aligned to the field direction upon zero field and field cooling, respectively.

Tuning selective reflection of light by surface anchoring in cholesteric cells with oblique helicoidal structures

NASA Astrophysics Data System (ADS)

Iadlovska, Olena S.; Maxwell, Graham R.; Babakhanova, Greta; Mehl, Georg H.; Welch, Christopher; Shiyanovskii, Sergij V.; Lavrentovich, Oleg D.

2018-04-01

Selective reflection of light by oblique helicoidal cholesteric (ChOH) can be tuned in a very broad spectral range by an applied electric field. In this work, we demonstrate that the peak wavelength of the selective reflection can be controlled by surface alignment of the director in sandwich cells. The peak wavelength is blue-shifted when the surface alignment is perpendicular to the bounding plates and red-shifted when it is planar. The effect is explained by the electric field redistribution within the cell caused by spatially varying heliconical ChOH structure. The observed phenomenon can be used in sensing applications.

A Unified Theory for the Blue- and Red-Shifting Phenomena in Hydrogen and Halogen Bonds.

PubMed

Wang, Changwei; Danovich, David; Shaik, Sason; Mo, Yirong

2017-04-11

Typical hydrogen and halogen bonds exhibit red-shifts of their vibrational frequencies upon the formation of hydrogen and halogen bonding complexes (denoted as D···Y-A, Y = H and X). The finding of blue-shifts in certain complexes is of significant interest, which has led to numerous studies of the origins of the phenomenon. Because charge transfer mixing (i.e., hyperconjugation in bonding systems) has been regarded as one of the key forces, it would be illuminating to compare the structures and vibrational frequencies in bonding complexes with the charge transfer effect "turned on" and "turned off". Turning off the charge transfer mixing can be achieved by employing the block-localized wave function (BLW) method, which is an ab initio valence bond (VB) method. Further, with the BLW method, the overall stability gained in the formation of a complex can be analyzed in terms of a few physically meaningful terms. Thus, the BLW method provides a unified and physically lucid way to explore the nature of red- and blue-shifting phenomena in both hydrogen and halogen bonding complexes. In this study, a direct correlation between the total stability and the variation of the Y-A bond length is established based on our BLW computations, and the consistent roles of all energy components are clarified. The n(D) → σ*(Y-A) electron transfer stretches the Y-A bond, while the polarization due to the approach of interacting moieties reduces the HOMO-LUMO gap and results in a stronger orbital mixing within the YA monomer. As a consequence, both the charge transfer and polarization stabilize bonding systems with the Y-A bond stretched and red-shift the vibrational frequency of the Y-A bond. Notably, the energy of the frozen wave function is the only energy component which prefers the shrinking of the Y-A bond and thus is responsible for the associated blue-shifting. The total variations of the Y-A bond length and the corresponding stretching vibrational frequency are thus determined by the competition between the frozen-energy term and the sum of polarization and charge transfer energy terms. Because the frozen energy is composed of electrostatic and Pauli exchange interactions and frequency shifting is a long-range phenomenon, we conclude that long-range electrostatic interaction is the driving force behind the frozen energy term.

A localized surface plasmon resonance (LSPR) immunosensor for CRP detection using 4-chloro-1-naphtol (4-CN) precipitation

NASA Astrophysics Data System (ADS)

Ha, Su-Ji; Park, Jin-Ho; Byun, Ju-Young; Ahn, Young-Deok; Kim, Min-Gon

2017-07-01

In this study, C-reactive protein (CRP) was detected by monitoring of LSPR shift promoted by precipitation of 4-chloro-1-naphthol (4-CN). The precipitation occurred by horseradish peroxide (HRP) catalyst which is modified at CRP-detection antibody utilized in sandwich enzyme-linked immunosorbent assay (ELISA) on gold nano bipyramid (GNBP) substrate. Due to 4-CN precipitates which are located nearby the surface of GNBP, local refractive index (RI) and molecular density were greatly increased. This phenomenon eventually induced strong spectral red-shift of absorption band of GNBP. An excellent linear relationship (R2=0.9895) between the LSPR shift and CRP concentration was obtained in the range from 100 pg/mL to 100 ng/mL and limit of detection (LOD) was reached to 87 pg/mL.

Contemporary Anglo-Jewish community leadership: coping with multiculturalism.

PubMed

Gidley, Ben; Kahn-Harris, Keith

2012-03-01

In this article, drawing on qualitative interviews and documentary analysis, we argue that the Jewish community in Britain has undergone a fundamental shift since 1990 from a 'strategy of security', a strategy of communal leadership based on emphasizing the secure British citizenship and belonging of the UK's Jews, to a 'strategy of insecurity', where the communal leadership instead stresses an excess of security among Anglo-Jewry. We demonstrate this based on two case studies: of the Jewish renewal movement in the 1990s and the 'new antisemitism' phenomenon of the 2000s. We conclude that this shift is tied to the shift from a monocultural Britain to an officially multicultural one, and that therefore there are lessons that can be taken from it for the study of British and other multiculturalisms. © London School of Economics and Political Science 2012.

Nurses aged over 50 years and their experiences of shift work.

PubMed

Clendon, Jill; Walker, Leonie

2013-10-01

The Late Career Nurse project examined views and characteristics of nurses working in New Zealand who were born before 1960. This paper focuses on the experiences of such nurses who undertake shift work. The mean age of registered nurses in New Zealand has been rising steadily, and 40% are now aged 50 years or over. While there is substantial literature on the phenomenon and consequences of the ageing nursing workforce, little is known of the particular experiences of nurses aged over 50 years who work shifts. An anonymous online survey was emailed to eligible nurse New Zealand Nurses Organisation members aged over 50 years in February 2012. Quantitative and qualitative analyses of the 3273 responses received were undertaken. Over 45% of respondents worked shifts or flexible hours. While shift work suited many, others noted deleterious effects on family and social relationships, physical and mental health (notably sleep patterns and fatigue), and decreasing tolerance for shift work as they age. Poor scheduling practices were particularly detrimental. Worldwide, workforce ageing means strategies are required to retain older nurses in the workforce. Improved scheduling practices including increasing access to flexible and part time work hours, and development of resources on coping with shift work are recommended. © 2013 John Wiley & Sons Ltd.

Method and system for dual resolution translation stage

DOEpatents

Halpin, John Michael

2014-04-22

A dual resolution translation stage includes a stage assembly operable to receive an optical element and a low resolution adjustment device mechanically coupled to the stage assembly. The dual resolution stage also includes an adjustable pivot block mechanically coupled to the stage assembly. The adjustable pivot block includes a pivot shaft. The dual resolution stage further includes a lever arm mechanically coupled to the adjustable pivot block. The lever arm is operable to pivot about the pivot shaft. The dual resolution stage additionally includes a high resolution adjustment device mechanically coupled to the lever arm and the stage assembly.

Anomalous time delays and quantum weak measurements in optical micro-resonators

PubMed Central

Asano, M.; Bliokh, K. Y.; Bliokh, Y. P.; Kofman, A. G.; Ikuta, R.; Yamamoto, T.; Kivshar, Y. S.; Yang, L.; Imoto, N.; Özdemir, Ş.K.; Nori, F.

2016-01-01

Quantum weak measurements, wavepacket shifts and optical vortices are universal wave phenomena, which originate from fine interference of multiple plane waves. These effects have attracted considerable attention in both classical and quantum wave systems. Here we report on a phenomenon that brings together all the above topics in a simple one-dimensional scalar wave system. We consider inelastic scattering of Gaussian wave packets with parameters close to a zero of the complex scattering coefficient. We demonstrate that the scattered wave packets experience anomalously large time and frequency shifts in such near-zero scattering. These shifts reveal close analogies with the Goos–Hänchen beam shifts and quantum weak measurements of the momentum in a vortex wavefunction. We verify our general theory by an optical experiment using the near-zero transmission (near-critical coupling) of Gaussian pulses propagating through a nano-fibre with a side-coupled toroidal micro-resonator. Measurements demonstrate the amplification of the time delays from the typical inverse-resonator-linewidth scale to the pulse-duration scale. PMID:27841269

A phenomenological view of language shift.

PubMed

Tsitsipis, Lukas D

2004-01-01

Sociolinguistic studies of language shift have in their majority framed their research object in a horizon of theoretically received variables such as class, ethnicity, locality, attitudes etc. In spite of a limited usefulness of such conceptual variables, and of a recently emerging focus on agency, negotiation, and praxis the best results we obtain have not questioned in a coherent and theoretically sound manner the continuing hegemony of mechanistic-metaphorical models (language death, language suicide). In this paper I propose to examine language shift as a multifaceted phenomenon, joining in this respect work by other linguistic anthropologists researching similar areas. I specifically argue that by replacing vertical concepts such as age and generation, and dichotomous logics such as center and periphery with phenomenologically inspired concepts such as typifications, consociateship, contemporariness, and stream of consciousness we are in a better position to generalize about language shift dynamics. Data for this work is derived primarily from the Albanian speech communities of modern Greece, but also from other communities for comparative purposes.

The Perceived Experience of Children Bereaved by Parental Suicide.

PubMed

Schreiber, Jennifer K; Sands, Diana C; Jordan, John R

2017-06-01

Children whose parent died by suicide are a vulnerable and underserved population. This phenomenon will be described, as well as implications for practice and research. "Double Whammy," a conceptualization of the overall experience of this marginalized group, emerged through two in-depth interviews from a phenomenological qualitative study with professionals who facilitate support groups for children bereaved by parental suicide. It was corroborated with current literature and practice experiences of the authors and their colleagues. Stigma was the largest contributor to the "Double Whammy," and the following themes emerged as well: feeling isolated, feeling abandoned, and feeling responsible. The self-volition of suicide challenges how bereaved children make meaning and internalize feelings about the deceased parent, one's self, and others. Developmentally appropriate education about suicide grief, depression, and normalizing the grief process is pivotal in helping children to effectively cope and manage their feelings.

Calcium signaling and cell proliferation.

PubMed

Pinto, Mauro Cunha Xavier; Kihara, Alexandre Hiroaki; Goulart, Vânia A M; Tonelli, Fernanda M P; Gomes, Katia N; Ulrich, Henning; Resende, Rodrigo R

2015-11-01

Cell proliferation is orchestrated through diverse proteins related to calcium (Ca(2+)) signaling inside the cell. Cellular Ca(2+) influx that occurs first by various mechanisms at the plasma membrane, is then followed by absorption of Ca(2+) ions by mitochondria and endoplasmic reticulum, and, finally, there is a connection of calcium stores to the nucleus. Experimental evidence indicates that the fluctuation of Ca(2+) from the endoplasmic reticulum provides a pivotal and physiological role for cell proliferation. Ca(2+) depletion in the endoplasmatic reticulum triggers Ca(2+) influx across the plasma membrane in an phenomenon called store-operated calcium entries (SOCEs). SOCE is activated through a complex interplay between a Ca(2+) sensor, denominated STIM, localized in the endoplasmic reticulum and a Ca(2+) channel at the cell membrane, denominated Orai. The interplay between STIM and Orai proteins with cell membrane receptors and their role in cell proliferation is discussed in this review. Copyright © 2015 Elsevier Inc. All rights reserved.

Extracellular matrix integrity: a possible mechanism for differential clinical effects among selective estrogen receptor modulators and estrogens?

PubMed

Cox, David A; Helvering, Leah M

2006-03-09

Recent gene microarray studies have illustrated heterogeneity in gene expression changes not only between estrogens and selective estrogen receptor modulators (SERMs), but also across different SERM molecules. In ovariectomized rats, this phenomenon was observed with respect to a number of genes involved in collagen turnover and extracellular matrix (ECM) integrity in the uterus and vaginal tissues. Preliminary mechanistic data suggest that these effects on ECM integrity may have relevance in the context of the effect of estrogens and some SERMs to increase the risk of pelvic organ prolapse and the incidence of urinary incontinence in postmenopausal women. Given the pivotal role of ECM integrity and collagen turnover in other tissues and disease states, these processes may provide a fruitful target for future research into the mechanisms for the heterogeneous pharmacology of estrogens and SERMs across different cell types and target tissues.

Evolution of double white dwarf binaries undergoing direct-impact accretion: Implications for gravitational wave astronomy

NASA Astrophysics Data System (ADS)

Kremer, Kyle; Breivik, Katelyn; Larson, Shane L.; Kalogera, Vassiliki

2017-01-01

For close double white dwarf binaries, the mass-transfer phenomenon known as direct-impact accretion (when the mass transfer stream impacts the accretor directly rather than forming a disc) may play a pivotal role in the long-term evolution of the systems. In this analysis, we explore the long-term evolution of white dwarf binaries accreting through direct-impact and explore implications of such systems to gravitational wave astronomy. We cover a broad range of parameter space which includes initial component masses and the strength of tidal coupling, and show that these systems, which lie firmly within the LISA frequency range, show strong negative chirps which can last as long as several million years. Detections of double white dwarf systems in the direct-impact phase by detectors such as LISA would provide astronomers with unique ways of probing the physics governing close compact object binaries.

Asymmetry in Object Substitution Masking Occurs Relative to the Direction of Spatial Attention Shift

ERIC Educational Resources Information Center

Hirose, Nobuyuki; Osaka, Naoyuki

2010-01-01

A sparse mask that persists beyond the duration of a target can reduce its visibility, a phenomenon called "object substitution masking". Y. Jiang and M. M. Chun (2001a) found an asymmetric pattern of substitution masking such that a mask on the peripheral side of the target caused stronger substitution masking than on the central side.…

The rise of the mediocre forest: why chronically stressed trees may better survive extreme episodic climate variability

Treesearch

Steven G. McNulty; Johnny L. Boggs; Ge Sun

2014-01-01

Anthropogenic climate change is a relatively new phenomenon, largely occurring over the past 150 years, and much of the discussion on climate change impacts to forests has focused on long-term shifts in temperature and precipitation. However, individual trees respond to the much shorter impacts of climate variability. Historically, fast growing, fully canopied, non-...

Drugs, Violence, and Trauma in Mexico and the USA.

PubMed

Puyana, Juan Carlos; Puyana, Juan Carlos Jacob; Rubiano, Andres Mariano; Montenegro, Jorge Hernan; Estebanez, Glyn O; Sanchez, Alvaro Ignacio; Vega-Rivera, Felipe

2017-01-01

The impact of illicit drug markets on the occurrence of violence varies tremendously depending on many factors. Over the last years, Mexico and the USA have increased security border issues that included many aspects of drug-related trade and criminal activities. Mexico experienced only a small reduction in trauma deaths after the enforcement of severe crime reinforcement policies. This strategy in the war on drugs is shifting the drug market to other Central American countries. This phenomenon is called the ballooning effect, whereby the pressure to control illicit drug-related activities in one particular area forces a shift to other more vulnerable areas that leads to an increase in crime and violence. A human rights crisis characterized by suffering, injury, and death related to drug trafficking continues to expand, resulting in the exorbitant loss of lives and cost in productivity across the continent. The current climate of social violence in Central America and the illegal immigration to the USA may be partially related to this phenomenon of drug trafficking, gang violence, and crime. A health care initiative as an alternative to the current war approach may be one of the interventions needed to reduce this crisis. © 2017 S. Karger AG, Basel.

Drugs, Violence, and Trauma in Mexico and the USA

PubMed Central

Puyana, Juan Carlos; Puyana, Juan Carlos Jacob; Rubiano, Andres Mariano; Montenegro, Jorge Hernan; Estebanez, Glyn O.; Sanchez, Alvaro Ignacio; Vega-Rivera, Felipe

2017-01-01

The impact of illicit drug markets on the occurrence of violence varies tremendously depending on many factors. Over the last years, Mexico and the USA have increased security border issues that included many aspects of drug-related trade and criminal activities. Mexico experienced only a small reduction in trauma deaths after the enforcement of severe crime reinforcement policies. This strategy in the war on drugs is shifting the drug market to other Central American countries. This phenomenon is called the ballooning effect, whereby the pressure to control illicit drug-related activities in one particular area forces a shift to other more vulnerable areas that leads to an increase in crime and violence. A human rights crisis characterized by suffering, injury, and death related to drug trafficking continues to expand, resulting in the exorbitant loss of lives and cost in productivity across the continent. The current climate of social violence in Central America and the illegal immigration to the USA may be partially related to this phenomenon of drug trafficking, gang violence, and crime. A health care initiative as an alternative to the current war approach may be one of the interventions needed to reduce this crisis. PMID:28329741

Midline Shift Threshold Value for Hemiparesis in Chronic Subdural Hematoma.

PubMed

Juković, Mirela F; Stojanović, Dejan B

2015-01-01

Chronic subdural hematoma (CSDH) has a variety of clinical presentations, with numerous neurological symptoms and signs. Hemiparesis is one of the leading signs that potentially indicates CSDH. Purpose of this study was to determine the threshold (cut-off) value of midsagittal line (MSL) shift after which hemiparesis is likely to appear. The study evaluated 83 patients with 53 unilateral and 30 bilateral CSDHs in period of three years. Evaluated computed tomography (CT) findings in patients with CSDH were diameter of the hematoma and midsagittal line shift, measured on non-contrast CT scan in relation with occurrence of hemiparesis. Threshold values of MSL shift for both types of CSDHs were obtained as maximal (equal) sensitivity and specificity (intersection of the curves). MSL is a good predictor for hemiparesis occurrence (total sample, AUROC 0.75, p=0.0001). Unilateral and bilateral CSDHs had different threshold values of the MSL for hemiparesis development. Results suggested that in unilateral CSDH the threshold values of MSL could be at 10 mm (AUROC=0.65; p=0.07). For bilateral CSDH the threshold level of MSL shift was 4.5 mm (AUROC=0.77; p=0.01). Our study pointed on the phenomenon that midsagittal line shift can predict hemiparesis occurrence. Hemiparesis in patients with bilateral CSDH was more related to midsagittal line shift compared with unilateral CSDH. When value of midsagittal line shift exceed the threshold level, hemiparesis occurs with certain probability.

Press-fit fixation using autologous bone in the tibial canal causes less enlargement of bone tunnel diameter in ACL reconstruction--a CT scan analysis three months postoperatively.

PubMed

Akoto, Ralph; Müller-Hübenthal, Jonas; Balke, Maurice; Albers, Malte; Bouillon, Bertil; Helm, Philip; Banerjee, Marc; Höher, Jürgen

2015-08-19

Bone tunnel enlargement is a phenomenon present in all anterior cruciate ligament (ACL)- reconstruction techniques. It was hypothesized that press-fit fixation using a free autograft bone plug reduces the overall tunnel size in the tibial tunnel. In a prospective cohort study twelve patients who underwent primary ACL reconstruction using an autologous quadriceps tendon graft and adding a free bone block for press-fit fixation (PF) in the tibial tunnel were matched to twelve patients who underwent ACL reconstruction with a hamstring graft and interference screw fixation (IF). The diameters of the bone tunnels were analysed by a multiplanar reconstruction technique (MPR) in a CT scan three months postoperatively. Manual and instrumental laxity (Lachman test, Pivot-shift test, Rolimeter) and functional outcome scores (International Knee Documentation Committee sore, Tegner activity level) were measured after one year follow up. In the PF group the mean bone tunnel diameter at the level of the joint entrance was not significantly enlarged. One and two centimeter distal to the bone tunnel diameter was reduced by 15% (p = .001). In the IF group the bone tunnel at the level of the joint entrance was enlarged by 14% (p = .001). One and two centimeter distal to the joint line the IF group showed a widening of the bone tunnel by 21% (p < .001) One and two centimeter below the joint line the bone tunnel was smaller in the PF group when compared to the IF group (p < .001). No significant difference for laxity test and functional outcome scores could be shown. This study demonstrates that press-fit fixation with free autologous bone plugs in the tibial tunnel results in significantly smaller diameter of the tibial tunnel compared to interference screw fixation.

Bone-Patellar Tendon-Bone Versus Soft-Tissue Allograft for Anterior Cruciate Ligament Reconstruction: A Systematic Review.

PubMed

Joyce, Christopher D; Randall, Kyle L; Mariscalco, Michael W; Magnussen, Robert A; Flanigan, David C

2016-02-01

To describe the outcomes of bone-patellar tendon-bone (BPTB) and soft-tissue allografts in anterior cruciate ligament (ACL) reconstruction with respect to graft failure risk, physical examination findings, instrumented laxity, and patient-reported outcomes. A search of the PubMed, Scopus, CINAHL (Cumulative Index to Nursing and Allied Health Literature) Complete, Cochrane Collaboration, and SPORTDiscus databases was performed. English-language studies with outcome data on primary ACL reconstruction with nonirradiated BPTB and soft-tissue allografts were identified. Outcome data included failure risk, physical examination findings, instrumented laxity measurements, and patient-reported outcome scores. Seventeen studies met the inclusion criteria. Of these studies, 11 reported on BPTB allografts exclusively, 5 reported on soft-tissue allografts exclusively, and 1 compared both types. The comparative study showed no difference in failure risk, Lachman grade, pivot-shift grade, instrumented laxity, or overall International Knee Documentation Committee score between the 2 allograft types. Data from all studies yielded a failure risk of 10.3% (95% confidence interval [CI], 4.5% to 18.1%) in the soft-tissue group and 15.2% (95% CI, 11.3% to 19.6%) in the BPTB group. The risk of a Lachman grade greater than 5 mm was 6.4% (95% CI, 1.7% to 13.7%) in the soft-tissue group and 8.6% (95% CI, 6.3% to 11.2%) in the BPTB group. The risk of a grade 2 or 3 pivot shift was 1.4% (95% CI, 0.3% to 3.3%) in the soft-tissue group and 4.1% (95% CI, 1.9% to 7.2%) in the BPTB group. One comparative study showed no difference in results after ACL reconstruction with nonirradiated BPTB and soft-tissue allografts. Inclusion of case series in the analysis showed qualitatively similar outcomes with the 2 graft types. Copyright © 2016 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Comparison of clinical outcomes and second-look arthroscopic findings after ACL reconstruction using a hamstring autograft or a tibialis allograft.

PubMed

Yoo, Seung-Hyun; Song, Eun-Kyoo; Shin, Young-Rok; Kim, Sung-Kyu; Seon, Jong-Keun

2017-04-01

The purpose of this prospective randomized clinical study was to compare the clinical and radiological outcomes, including tibial tunnel widening and the progression of osteoarthritis after ACL reconstruction using a hamstring autograft or a tibialis allograft. In addition, we compared the graft tear and synovial coverage of grafts in patients that underwent the second-look arthroscopy. Among 184 patients with an ACL injury who underwent ACL reconstruction, 68 patients of autograft group and 64 patients of tibialis allograft group were included for this study after minimum of 2-year follow-up. The Lachman and pivot-shift tests, Tegner activity score, Lysholm knee score, and IKDC score were compared between the two groups. The quadriceps and hamstring isokinetic strengths using dynamometer were also compared. Degree of OA was determined using the Kellgren-Lawrence grading system on the weight-bearing radiographs. In total, 51 patients (26 patients in autograft group and 25 in the tibialis allograft group) underwent the second-look arthroscopy, in which we compared the apparent tear of graft and synovial coverage of grafts. At the final follow-up, there were no statistical significances in the two groups in Lachman and pivot-shift tests (n.s.). The Tegner activity, Lysholm knee score, and IKDC scores were similar in the two groups. Moreover, no significant differences were observed in the muscle power (n.s.). Some patients showed the progression of OA (five in autograft and four in allograft groups) without intergroup difference (n.s.). Regarding the findings of second-look arthroscopy, although there was no significant difference in graft tear, synovial coverage was better in autograft group than in allograft group. Even though hamstring autografts and tibialis allografts provided good functional outcomes without significant differences, the second-look arthroscopy revealed that hamstring autografts produced better synovial coverage than tibialis allograft. I.

Arthroscopic single-bundle anterior cruciate ligament reconstruction with six-strand hamstring tendon allograft versus bone-patellar tendon-bone allograft.

PubMed

Dai, Chengliang; Wang, Fei; Wang, Xiaomeng; Wang, Ruipeng; Wang, Shengjie; Tang, Shiyu

2016-09-01

The aim of this study was to compare the clinical outcomes of arthroscopic single-bundle anterior cruciate ligament (ACL) reconstruction with six-strand hamstring tendon (HT) allograft versus bone-patellar tendon-bone (BPTB) allograft. The prospective randomized controlled trial was included 129 patients. Sixty-nine patients received reconstruction with six-strand HT allografts (HT group), whereas 60 patients with BPTB allografts (BPTB group). Outcome assessment included re-rupture findings, International Knee Documentation Committee (IKDC) scores, Lysholm scores, KT-1000 arthrometer, Lachman test, pivot-shift test, range of motion (ROM) and single-leg hop test. At a mean follow-up of 52 months, 113 patients (HT group, 61 patients; BPTB group, 52 patients) completed a minimum 4-year follow-up. Four patients in HT group and six in BPTB group experienced ACL re-rupture (6.2 vs. 10.3 %) and received revision surgery. Significant between-group differences were observed in KT-1000 outcomes and pivot-shift test 1 (1.2 ± 1.5 vs. 1.8 ± 1.3, p = 0.025; positive rate 6.5 vs. 18.9 %, p = 0.036), 2 (1.1 ± 1.4 vs. 1.6 ± 1.2, p = 0.044; 8.1 vs. 20.7 %, p = 0.039), 4 (1.1 ± 1.5 vs. 1.7 ± 1.4, p = 0.031; 9.7 vs. 25 %, p = 0.012) years postoperatively. The outcomes between the two groups were comparable in terms of IKDC scores, Lysholm scores, Lachman test, ROM and single-leg hop test. Six-strand HT allograft achieved superior anteroposterior and rotational stability after single-bundle ACL reconstruction. It is a reasonable graft substitute for ACL reconstruction. II.

Clinical and functional outcome of anterior cruciate ligament reconstruction in the recreational athlete over the age of 35.

PubMed

Novak, P J; Bach, B R; Hager, C A

1996-01-01

This study examined the functional, objective, and subjective outcome of anterior cruciate ligament (ACL) reconstruction in recreational athletes > or = 35 years after a minimum of 2 years of follow-up. Patients > or = 35 years who underwent ACL reconstruction by a single surgeon were identified from our surgical database. Nineteen knees in 18 (62% follow-up) patients were available for review by an independent examiner. The patients underwent physical examination, radiographs, functional testing, isokinetic strength testing, and instrumented ligament arthrometer testing. All were seen at a minimum of 2 years of follow-up. The average age was 40 years. Five of 19 underwent reconstruction less than 1 month after injury, and the remainder underwent reconstruction for chronic injuries. All patients preoperatively had at least a grade 2 Lachman and a positive pivot shift noted on physical examination. After a minimum of 2 years of follow-up, 17 of 18 patients had a stable knee on objective testing, including a negative Lachman and pivot shift. Seventeen patients (94%) had < 3 mm side-to-side difference on maximum manual arthrometric testing. Only one patient had > 3 cm prone heel height difference, and all patients had > 125 degrees of flexion. Mean thigh circumference difference was 0.5 cm. Isokinetic testing demonstrated a mean 11%, 7%, and 4% quadriceps asymmetry at 60 degrees, 180 degrees, and 240 degrees/second, respectively. However, functional testing revealed only a mean 6% asymmetry on vertical jump, single leg hop, and timed 6 meter hop. Seventeen of 18 patients were satisfied with their results. The mean postoperative Lysholm Rating Scale score was 93. The mean Noyes Sports Activity Scale score was 86, improved from 31 preoperatively. Thirteen of 18 returned to their preinjury level of sports performance. These results indicate that ACL reconstruction in patients over the age of 35 has functional, objective, and subjective results comparable to those of a younger patient population.

Study of Imaging Pattern in Bone Marrow Oedema in MRI in Recent Knee Injuries and its Correlation with Type of Knee Injury.

PubMed

Sahoo, Kulamani; Garg, Ashish; Saha, Pramod; Dodia, Jainesh Valjibhai; Raj, Vinay Rajappa; Bhairagond, Shweta Jagadish

2016-04-01

The knee is a major weight bearing joint that provides mobility and stability during physical activity as well as balance while standing. If the knee is exposed to forces beyond its physiologic range, risk of injury to bone or soft tissue structures increases. A thorough understanding of knee injury patterns and their mechanisms may help in achieving more accurate assessment of injuries. To identify imaging pattern in bone marrow oedema and to correlate the pattern of bone marrow oedema retrospectively with type of knee injury from clinical history. A cross-sectional study was done on all patients referred to Krishna Hospital, Karad for MRI knee with history of recent (< 6 weeks) knee injury. Study was conducted between May 2014 to September 2015 with a sample size of 200 patients. Plain radiograph of knee was done in all patients and they were scanned using 1.5 Tesla Seimens Avanto (Tim + Dot) with Tx/Rx 15 channel knee coil # Tim. Among the 200 cases, bone marrow contusion was noted in 138 cases (69%) and absent contusion in 62 cases (31%). Bone marrow contusion showed five patterns (according to Sanders classification) i.e., Clip injury in 39 cases (28.3%), Pivot shift injury in 78 cases (56.5%), Dashboard injury in eight cases (5.8%), Hyperextension injury in four cases (2.9%), Lateral patellar dislocation in three cases (2.2%). In six cases (4.3%) no pattern of bone marrow contusion could be explained and was categorized as unclassified pattern. Pivot shift pattern is most common contusion pattern and the most common type/mode of sports related injury. By analysing bone marrow contusion pattern, type/mode can be determined in most of the cases. By applying a biomechanical approach in MR interpretation, it is possible to detect lesions like ligament rupture and osseous contusion, to predict subtle but it might overlook important abnormalities.

Double-layer versus single-layer bone-patellar tendon-bone anterior cruciate ligament reconstruction: a prospective randomized study with 3-year follow-up.

PubMed

Mei, Xiaoliang; Zhang, Zhenxiang; Yang, Jingwen

2016-12-01

To evaluate the clinical results of a randomized controlled trial of single-layer versus double-layer bone-patellar tendon-bone (BPTB) anterior cruciate ligament (ACL) reconstruction. Fifty-eight subjects who underwent primary ACL reconstruction with a BPTB allograft were prospectively randomized into two groups: single-layer reconstruction (n = 31) and double-layer reconstruction (n = 27). The following evaluation methods were used: clinical examination, KT-1000 arthrometer measurement, muscle strength, Tegner activity score, Lysholm score, subjective rating scale regarding patient satisfaction and sports performance level, graft retear, contralateral ACL tear, and additional meniscus surgery. Forty-eight subjects (24 in single-layer group and 24 in double-layer group) who were followed up for 3 years were evaluated. Preoperatively, there were no differences between the groups. At 3-year follow-up, the Lachman and pivot-shift test results were better in the double-layer group (P = 0.019 and P < 0.0001, respectively). KT measurements were better in the double-layer group (mean 2.9 versus 1.5 mm; P = 0.0025). The Tegner score was also better in the double-layer group (P = 0.024). There were no significant differences in range of motion, muscle strength, Lysholm score, subjective rating scale, graft retear, and secondary meniscal tear. In ACL reconstruction, double-layer BPTB reconstruction was significantly better than single-layer reconstruction regarding anterior and rotational stability at 3-year follow-up. The results of KT measurements and the Lachman and pivot-shift tests were significantly better in the double-layer group, whereas there was no difference in the anterior drawer test results. The Tegner score was also better in the double-layer group; however, there were no differences in the other subjective findings.

The Role of Gut Microflora and the Cholinergic Anti-inflammatory Neuroendocrine System in Diabetes Mellitus

PubMed Central

Parekh, Parth J.; Nayi, Vipul R.; Johnson, David A.; Vinik, Aaron I.

2016-01-01

The obesity epidemic has drastically impacted the state of health care in the United States. Paralleling this epidemic is the incidence of diabetes mellitus, with a notable shift toward a much younger age of onset. While central to the pathogenesis of diabetes associated with obesity is the role of inflammation attributed to “adiposopathy.” Emerging data suggest that changes in sympathetic/parasympathetic balance regulated by the brain precede changes in the inflammatory cascade. It has now been established that the gut microflora contributes significantly to the activation and inhibition of autonomic control and impact the set of the neuroinflammatory inhibitory reflex mediated by the cholinergic nervous system. There has been a paradigm shift toward further investigating commensal bacteria in the pathogenesis of obesity and diabetes mellitus and its complications, as dysbiosis is thought to play a pivotal role in diabetic-associated disorders. This paper is intended to evaluate the role of intestinal dysbiosis in the pathogenesis of diabetes mellitus and examine the potential for restoration of balance via use of probiotics. PMID:27375553

Characteristics of Clinical Studies Conducted Over the Total Product Life Cycle of High-Risk Therapeutic Medical Devices Receiving FDA Premarket Approval in 2010 and 2011.

PubMed

Rathi, Vinay K; Krumholz, Harlan M; Masoudi, Frederick A; Ross, Joseph S

2015-08-11

The US Food and Drug Administration (FDA) approves high-risk medical devices, those that support or sustain human life or present potential unreasonable risk to patients, via the Premarket Approval (PMA) pathway. The generation of clinical evidence to understand device safety and effectiveness is shifting from predominantly premarket to continual study throughout the total product life cycle. To characterize the clinical evidence generated for high-risk therapeutic devices over the total product life cycle. All clinical studies of high-risk therapeutic devices receiving initial market approval via the PMA pathway in 2010 and 2011 identified through ClinicalTrials.gov and publicly available FDA documents as of October 2014. Studies were characterized by type (pivotal, studies that served as the basis of FDA approval; FDA-required postapproval studies [PAS]; or manufacturer/investigator-initiated); premarket or postmarket; status (completed, ongoing, or terminated/unknown); and design features, including enrollment, comparator, and longest duration of primary effectiveness end point follow-up. In 2010 and 2011, 28 high-risk therapeutic devices received initial marketing approval via the PMA pathway. We identified 286 clinical studies of these devices: 82 (28.7%) premarket and 204 (71.3%) postmarket, among which there were 52 (18.2%) nonpivotal premarket studies, 30 (10.5%) pivotal premarket studies, 33 (11.5%) FDA-required PAS, and 171 (59.8%) manufacturer/investigator-initiated postmarket studies. Six of 33 (18.2%) PAS and 20 of 171 (11.7%) manufacturer/investigator-initiated postmarket studies were reported as completed. No postmarket studies were identified for 5 (17.9%) devices; 3 or fewer were identified for 13 (46.4%) devices overall. Median enrollment was 65 patients (interquartile range [IQR], 25-111), 241 patients (IQR, 147-415), 222 patients (IQR, 119-640), and 250 patients (IQR, 60-800) for nonpivotal premarket, pivotal, FDA-required PAS, and manufacturer/investigator-initiated postmarket studies, respectively. Approximately half of all studies used no comparator (pivotal: 13/30 [43.3%]; completed postmarket: 16/26 [61.5%]; ongoing postmarket: 70/153 [45.8%]). Median duration of primary effectiveness end point follow-up was 3.0 months (IQR, 3.0-12.0), 9.0 months (IQR, 0.3-12.0), and 12.0 months (IQR, 7.0-24.0) for pivotal, completed postmarket, and ongoing postmarket studies, respectively. Among high-risk therapeutic devices approved via the FDA PMA pathway, total product life cycle evidence generation varied in both the number and quality of premarket and postmarket studies, with approximately 13% of initiated postmarket studies completed between 3 and 5 years after FDA approval.

Feature-binding errors after eye movements and shifts of attention.

PubMed

Golomb, Julie D; L'heureux, Zara E; Kanwisher, Nancy

2014-05-01

When people move their eyes, the eye-centered (retinotopic) locations of objects must be updated to maintain world-centered (spatiotopic) stability. Here, we demonstrated that the attentional-updating process temporarily distorts the fundamental ability to bind object locations with their features. Subjects were simultaneously presented with four colors after a saccade-one in a precued spatiotopic target location-and were instructed to report the target's color using a color wheel. Subjects' reports were systematically shifted in color space toward the color of the distractor in the retinotopic location of the cue. Probabilistic modeling exposed both crude swapping errors and subtler feature mixing (as if the retinotopic color had blended into the spatiotopic percept). Additional experiments conducted without saccades revealed that the two types of errors stemmed from different attentional mechanisms (attention shifting vs. splitting). Feature mixing not only reflects a new perceptual phenomenon, but also provides novel insight into how attention is remapped across saccades.

Effects of 946-nm thermal shift and broadening on Nd3+:YAG laser performance

NASA Astrophysics Data System (ADS)

Seyed Ebrahim, Pourmand; Ghasem, Rezaei

2015-12-01

Spectroscopic properties of flashlamp pumped Nd3+:YAG laser are studied as a function of temperature in a range from -30 °C to 60 °C. The spectral width and shift of quasi three-level 946.0-nm inter-Stark emission within the respective intermanifold transitions of 4F3/2 → 4I9/2 are investigated. The 946.0-nm line shifts toward the shorter wavelength and broadens. In addition, the threshold power and slope efficiency of the 946.0-nm laser line are quantified with temperature. The lower the temperature, the lower the threshold power is and the higher the slope efficiency of the 946.0-nm laser line is, thus the higher the laser output is. This phenomenon is attributed to the ion-phonon interaction and the thermal population in the ground state. Project supported by Estahban Branch, Islamic Azad University.

Improved Intrapulse Raman Scattering Control via Asymmetric Airy Pulses

NASA Astrophysics Data System (ADS)

Hu, Yi; Tehranchi, Amirhossein; Wabnitz, Stefan; Kashyap, Raman; Chen, Zhigang; Morandotti, Roberto

2015-02-01

We experimentally demonstrate the possibility of tuning the frequency of a laser pulse via the use of an Airy pulse-seeded soliton self-frequency shift. The intrinsically asymmetric nature of Airy pulses, typically featured by either leading or trailing oscillatory tails (relatively to the main lobe), is revealed through the nonlinear generation of both a primary and a secondary Raman soliton self-frequency shift, a phenomenon which is driven by the soliton fission processes. The resulting frequency shift can be carefully controlled by using time-reversed Airy pulses or, alternatively, by applying an offset to the cubic phase modulation used to generate the pulses. When compared with the use of conventional chirped Gaussian pulses, our technique brings about unique advantages in terms of both efficient frequency tuning and feasibility, along with the generation and control of multicolor Raman solitons with enhanced tunability. Our theoretical analysis agrees well with our experimental observations.

Shift in speed selectivity of visual cortical neurons: A neural basis of perceived motion contrast

PubMed Central

Li, Chao-Yi; Lei, Jing-Jiang; Yao, Hai-Shan

1999-01-01

The perceived speed of motion in one part of the visual field is influenced by the speed of motion in its surrounding fields. Little is known about the cellular mechanisms causing this phenomenon. Recordings from mammalian visual cortex revealed that speed preference of the cortical cells could be changed by displaying a contrast speed in the field surrounding the cell’s classical receptive field. The neuron’s selectivity shifted to prefer faster speed if the contextual surround motion was set at a relatively lower speed, and vice versa. These specific center–surround interactions may underlie the perceptual enhancement of speed contrast between adjacent fields. PMID:10097161

Single-Source Molecular Precursor for Synthesis of CdS Nanoparticles and Nanoflowers

NASA Astrophysics Data System (ADS)

Salavati-Niasari, Masoud; Sobhani, Azam

2012-04-01

CdS Semiconductor nanostructures were synthesized by using two different methods. Using triphenylphosphine (C18H15P) and oleylamine (C18H37N) as surfactant, CdS semiconductor nanocrystals with a size ranging from 30 to 90 nm can be synthesized by thermal decomposition of precursor [bis(thiosemicarbazide)cadmium(II)]. CdS nanoflowers were synthesized via hydrothermal decomposition of [bis(thiosemicarbazide) cadmium(II)] without any surfactant. X-ray diffraction (XRD) patterns confirm that the resulting samples were a pure hexagonal phase of CdS. The optical property test indicates that the absorption peak of the samples shifts towards short wavelength, and the blue shift phenomenon might be ascribed to the quantum effect.

How to induce multiple delays in coupled chaotic oscillators?

NASA Astrophysics Data System (ADS)

Bhowmick, Sourav K.; Ghosh, Dibakar; Roy, Prodyot K.; Kurths, Jürgen; Dana, Syamal K.

2013-12-01

Lag synchronization is a basic phenomenon in mismatched coupled systems, delay coupled systems, and time-delayed systems. It is characterized by a lag configuration that identifies a unique time shift between all pairs of similar state variables of the coupled systems. In this report, an attempt is made how to induce multiple lag configurations in coupled systems when different pairs of state variables attain different time shift. A design of coupling is presented to realize this multiple lag synchronization. Numerical illustration is given using examples of the Rössler system and the slow-fast Hindmarsh-Rose neuron model. The multiple lag scenario is physically realized in an electronic circuit of two Sprott systems.

Nonreciprocal Localization of Photons

NASA Astrophysics Data System (ADS)

Ramezani, Hamidreza; Jha, Pankaj K.; Wang, Yuan; Zhang, Xiang

2018-01-01

We demonstrate that it is possible to localize photons nonreciprocally in a moving photonic lattice made by spatiotemporally modulating the atomic response, where the dispersion acquires a spectral Doppler shift with respect to the probe direction. A static defect placed in such a moving lattice produces a spatial localization of light in the band gap with a shifting frequency that depends on the direction of incident field with respect to the moving lattice. This phenomenon has an impact not only in photonics but also in broader areas such as condensed matter and acoustics, opening the doors for designing new devices such as compact isolators, circulators, nonreciprocal traps, sensors, unidirectional tunable filters, and possibly even a unidirectional laser.

By the light of the silvery Moon: fact and fiction

NASA Astrophysics Data System (ADS)

Ciocca, Marco; Wang, Jing

2013-05-01

Is moonlight ‘silver’ or ‘cold’? In this paper we discuss the interesting combination of factors that contribute to the common descriptions of moonlight. Sunlight is reflected from the lunar surface and red-shifted. When traversing the atmosphere, moonlight is further depleted of short wavelength content by Rayleigh scattering. We measured the spectra of the moonlight to show these effects and compared them with sunlight. All measurements, including spectral reflectance, suggest that moonlight is redder than sunlight. The silvery Moon is just an illusion due to the properties and behaviour of our own eyes, including the responses of rods and cones and the physiological perceptive phenomenon called Purkinje shift.

The Economics and Politics of Cost Sharing in Higher Education: Comparative Perspectives

ERIC Educational Resources Information Center

Johnstone, Bruce, D

2004-01-01

Cost-sharing, or the shift in at least part of the higher educational cost burden from governments (or taxpayers) to parents and students, is a worldwide trend manifested in the introduction of (or in sharp increases in) tuition fees, user charges for lodging and food, and in the diminution of student grants. The phenomenon is seen even in Europe,…

The MOOC Moment and the End of Reform

ERIC Educational Resources Information Center

Bady, Aaron

2013-01-01

The Massive Open Online Courses (MOOC) phenomenon has happened very quickly and is also a shift in discourse. This article aims to slow things down and go through the last year or so with a bit more care than we're usually able to do in order to do a "close reading" of the year of the MOOC. Author Aaron Brady ventures an opinion to say…

Characterizing Brazilian fire and estimating areas burned by using the Airborne Infrared Disaster Assessment System

Treesearch

James A. Brass; Liane S. Guild; Philip J. Riggan; Vincent G. Ambrosia; Robert N. Lockwood; A. Pereira Joao

1996-01-01

Biomass burning is a common force in much of the developing tropical world and has wide-ranging environmental impacts. Fire is an important component in tropical deforestation and is often used to clear broad expanses of land for shifting agriculture, dispose of crop residue, and "clean" pastures for cattle grazing. It is part of a complex social phenomenon...

Response shift in quality of life assessment among cancer patients: A study from Iran

PubMed Central

Hosseini, Bayan; Nedjat, Saharnaz; Zendehdel, Kazem; Majdzadeh, Reza; Nourmohammadi, Azam; Montazer, Ali

2017-01-01

Background: During the course of disease, particularly of chronic diseases, changes in internal standards cause certain changes in the estimation of quality of life (QOL). These changes indicate the phenomenon of ‘response shift’. The present study aimed at assessing response shift in different scales of QOL in Iranian cancer patients. Methods: To assess response shift through the ‘then test’ approach, we asked 211 cancer patients to complete the EORTC QLQ-C30 questionnaire at pretest (at the beginning of the study), posttest (3 months later), and then test (administered immediately after the posttest). Paired t test and Cohen’s effect size were used for comparison. Results: Response shift was significant in all 4 scales under study, i.e. fatigue, pain, emotional functioning, and general QOL (p<0.001). Fatigue, pain, and global QOL have deteriorated significantly with then test approach and emotional function was significantly improved. Conclusion: We observed a response shift in Iranian cancer patients in our study. Thus, in light of the multifactorial nature of QOL and the effect of the response shift bias on different aspects of QOL changes, it is of utmost importance to keep this bias in mind when interpreting the results and managing cancer patients’ treatment regimens. PMID:29951421

Parallel pivoting combined with parallel reduction

NASA Technical Reports Server (NTRS)

Alaghband, Gita

1987-01-01

Parallel algorithms for triangularization of large, sparse, and unsymmetric matrices are presented. The method combines the parallel reduction with a new parallel pivoting technique, control over generations of fill-ins and a check for numerical stability, all done in parallel with the work being distributed over the active processes. The parallel technique uses the compatibility relation between pivots to identify parallel pivot candidates and uses the Markowitz number of pivots to minimize fill-in. This technique is not a preordering of the sparse matrix and is applied dynamically as the decomposition proceeds.

Home-grown slaves: women, reproduction, and the abolition of the slave trade, Jamaica 1788-1807.

PubMed

Turner, Sasha

2011-01-01

Once the British transatlantic slave trade came under abolitionists' scrutiny in 1788, West Indian slaveholders had to consider alternative methods of obtaining well-needed laborers. This article examines changes in enslaved women's working lives as planters sought to increase birth rates to replenish declining laboring populations. By focusing more on variances in work assignment and degrees of punishment rather than their absence, this article establishes that enslaved women in Jamaica experienced a considerable shift in their work responsibilities and their subjection to discipline as slaveholders sought to capitalize on their abilities to reproduce. Enslaved women's reproductive capabilities were pivotal for slavery and the plantation economy's survival once legal supplies from Africa were discontinued.

Developing novel chemical entities for the treatment of lysosomal storage disorders: an academic perspective.

PubMed

Shayman, James A

2015-12-15

Historically, most Federal Drug Administration-approved drugs were the result of "in-house" efforts within large pharmaceutical companies. Over the last two decades, this paradigm has steadily shifted as the drug industry turned to startups, small biotechnology companies, and academia for the identification of novel drug targets and early drug candidates. This strategic pivot has created new opportunities for groups less traditionally associated with the creation of novel therapeutics, including small academic laboratories, for engagement in the drug discovery process. A recent example of the successful development of a drug that had its origins in academia is eliglustat tartrate, an oral agent for Gaucher disease type 1. Copyright © 2015 the American Physiological Society.

Supplementing the neurosurgical virtuoso: evolution of automation from mythology to operating room adjunct.

PubMed

Attenello, Frank J; Lee, Brian; Yu, Cheng; Liu, Charles Y; Apuzzo, Michael L J

2014-01-01

A central concept of scientific advancement in the medical and surgical fields is the incorporation of successful emerging ideas and technologies throughout the scope of human endeavors. The field of automation and robotics is a pivotal representation of this concept. Arising in the mythology of Homer, the concept of automation and robotics grew exponentially over the millennia to provide the substrate for a paradigm shift in the current and future practice of neurosurgery. We trace the growth of this field from the seminal concepts of Homer and Aristotle to early incorporation into neurosurgical practice. Resulting changes provide drastic and welcome advances in areas of visualization, haptics, acoustics, dexterity, tremor reduction, motion scaling, and surgical precision. Published by Elsevier Inc.

Body position-dependent shift in odor percept present only for perithreshold odors.

PubMed

Lundström, Johan N; Boyle, Julie A; Jones-Gotman, Marilyn

2008-01-01

We recently demonstrated that a supine position causes a decrease in olfactory sensitivity compared with an upright position. We pursued that initial finding in 3 separate experiments in which we explored the extent of, and mechanism underlying, this phenomenon. In Experiment 1, we replicated the decrease in olfactory sensitivity when in a supine compared with an upright position. In Experiment 2, we measured body position-dependent shifts in physiological variables and sniff measures while smelling suprathreshold odorants and performing a perithreshold odor intensity discrimination task. Olfactory performances were reduced while supine. However, no relationships between the shift in olfactory performances and either the physiological variables or sniff measures were found. In Experiment 3, we determined that there were no position-dependent shifts in ability to discriminate or identify suprathreshold odors or rate them for pleasantness, intensity, or familiarity. However, a drop in scores was observed, and performance was slowed, on a cognitive skill while supine. These results demonstrate a body position-dependent shift in olfactory sensitivity only for perithreshold odors that appears to be mediated by cognitive rather than physiological factors. Implications for olfactory imaging studies are discussed.

On non-local energy transfer via zonal flow in the Dimits shift

DOE PAGES

St-Onge, Denis A.

2017-10-10

The two-dimensional Terry–Horton equation is shown to exhibit the Dimits shift when suitably modified to capture both the nonlinear enhancement of zonal/drift-wave interactions and the existence of residual Rosenbluth–Hinton states. This phenomenon persists through numerous simplifications of the equation, including a quasilinear approximation as well as a four-mode truncation. It is shown that the use of an appropriate adiabatic electron response, for which the electrons are not affected by the flux-averaged potential, results in anmore » $$\\boldsymbol{E}\\times \\boldsymbol{B}$$ nonlinearity that can efficiently transfer energy non-locally to length scales of the order of the sound radius. The size of the shift for the nonlinear system is heuristically calculated and found to be in excellent agreement with numerical solutions. The existence of the Dimits shift for this system is then understood as an ability of the unstable primary modes to efficiently couple to stable modes at smaller scales, and the shift ends when these stable modes eventually destabilize as the density gradient is increased. This non-local mechanism of energy transfer is argued to be generically important even for more physically complete systems.« less

Expansion Under Climate Change: The Genetic Consequences.

PubMed

Garnier, Jimmy; Lewis, Mark A

2016-11-01

Range expansion and range shifts are crucial population responses to climate change. Genetic consequences are not well understood but are clearly coupled to ecological dynamics that, in turn, are driven by shifting climate conditions. We model a population with a deterministic reaction-diffusion model coupled to a heterogeneous environment that develops in time due to climate change. We decompose the resulting travelling wave solution into neutral genetic components to analyse the spatio-temporal dynamics of its genetic structure. Our analysis shows that range expansions and range shifts under slow climate change preserve genetic diversity. This is because slow climate change creates range boundaries that promote spatial mixing of genetic components. Mathematically, the mixing leads to so-called pushed travelling wave solutions. This mixing phenomenon is not seen in spatially homogeneous environments, where range expansion reduces genetic diversity through gene surfing arising from pulled travelling wave solutions. However, the preservation of diversity is diminished when climate change occurs too quickly. Using diversity indices, we show that fast expansions and range shifts erode genetic diversity more than slow range expansions and range shifts. Our study provides analytical insight into the dynamics of travelling wave solutions in heterogeneous environments.

Frequency Shift During Mass Properties Testing Using Compound Pendulum Method

NASA Technical Reports Server (NTRS)

Wolfe, David; Regan, Chris

2012-01-01

During mass properties testing on the X-48B Blended Wing Body aircraft (The Boeing Company, Chicago, Illinois) at the National Aeronautics and Space Administration Dryden Flight Research Center, Edwards, California, large inertia measurement errors were observed in results from compound pendulum swings when compared to analytical models. By comparing periods of oscillations as measured from an average over the test period versus the period of each oscillation, it was noticed that the frequency of oscillation was shifting significantly throughout the test. This phenomenon was only noticed during compound pendulum swings, and not during bifilar pendulum swings. The frequency shift was only visible upon extensive data analysis of the frequency for each oscillation, and did not appear in averaged frequency data over the test period. Multiple test articles, test techniques, and hardware setups were used in attempts to eliminate or identify the cause of the frequency shift. Plotting the frequency of oscillation revealed a region of minimal shift that corresponded to a larger amplitude range. This region of minimal shift provided the most accurate results compared to a known test article; however, the amplitudes that produce accurate inertia measurements are amplitudes larger than those generally accepted in mass properties testing. This paper examines two case studies of the frequency shift, using mass properties testing performed on a dummy test article, and on the X-48B Blended Wing Body aircraft.

The role of conceptual knowledge in understanding synaesthesia: Evaluating contemporary findings from a “hub-and-spokes” perspective

PubMed Central

Chiou, Rocco

2014-01-01

Synesthesia is a phenomenon in which stimulation in one sensory modality triggers involuntary experiences typically not associated with that stimulation. Inducing stimuli (inducers) and synesthetic experiences (concurrents) may occur within the same modality (e.g., seeing colors while reading achromatic text) or span across different modalities (e.g., tasting flavors while listening to music). Although there has been considerable progress over the last decade in understanding the cognitive and neural mechanisms of synesthesia, the focus of current neurocognitive models of synesthesia does not encompass many crucial psychophysical characteristics documented in behavioral research. Prominent theories of the neurophysiological basis of synesthesia construe it as a perceptual phenomenon and hence focus primarily on the modality-specific brain regions for perception. Many behavioral studies, however, suggest an essential role for conceptual-level information in synesthesia. For example, there is evidence that synesthetic experience arises subsequent to identification of an inducing stimulus, differs substantially from real perceptual events, can be akin to perceptual memory, and is susceptible to lexical/semantic contexts. These data suggest that neural mechanisms lying beyond the realm of the perceptual cortex (especially the visual system), such as regions subserving conceptual knowledge, may play pivotal roles in the neural architecture of synesthesia. Here we discuss the significance of non-perceptual mechanisms that call for a re-evaluation of the emphasis on synesthesia as a perceptual phenomenon. We also review recent studies which hint that some aspects of synesthesia resemble our general conceptual knowledge for object attributes, at both psychophysical and neural levels. We then present a conceptual-mediation model of synesthesia in which the inducer and concurrent are linked within a conceptual-level representation. This “inducer-to-concurrent” nexus is maintained within a supramodal “hub,” while the subjective (bodily) experience of its resultant concurrent (e.g., a color) may then require activation of “spokes” in the perception-related cortices. This hypothesized “hub-and-spoke” structure would engage a distributed network of cortical regions and may account for the full breadth of this intriguing phenomenon. PMID:24653707

Micromechanisms with floating pivot

DOEpatents

Garcia, Ernest J.

2001-03-06

A new class of tilting micromechanical mechanisms have been developed. These new mechanisms use floating pivot structures to relieve some of the problems encountered in the use of solid flexible pivots.

The Carbon Balance Pivot Point of Southwestern U.S. Semiarid Ecosystems: Insights From the 21st Century Drought

NASA Astrophysics Data System (ADS)

Scott, R. L.; Biederman, J.; Barron-Gafford, G.; Hamerlynck, E. P.

2015-12-01

Global-scale studies indicate that semiarid ecosystems strongly regulate the long-term trend and interannual variability of the terrestrial carbon sink, possibly due to changes in vegetation and an inherent sensitivity to changes in water availability. However, we lack understanding of how climate shifts, such as the ongoing decadal-scale drought in the Southwest US, impact carbon sink functioning in semiarid ecosystems with differing structure. Therefore, we investigated the response of net ecosystem production of carbon dioxide (NEP) to changes in annual water availability in four Southwest US ecosystems varying in relative shrub, tree and grass abundance. Using eddy covariance carbon dioxide and water vapor flux measurements collected over the last drought-impacted decade, we identified a precipitation "pivot point" in the annual carbon balance for each ecosystem type where annual NEP switched from negative to positive. At the three sites with larger amounts of grass, rather than woody plant, cover, pivot points were closer to the drought-period mean annual precipitation (MAP) than MAP over the preceding 30 years, suggesting the carbon pools of these grassier ecosystems have more quickly adjusted to the decadal-scale drought. Current-year water availability, as quantified by evapotranspiration (ET) overwhelmingly drove the response of gross ecosystem photosynthesis (GEP) and respiration (Reco) fluxes. Ecosystem water use efficiency (GEP/ET) increased with water availability and leaf area index, resulting in a more efficient photosynthetic use of water in wetter years and at wetter sites. Grasslands supported a higher leaf area than shrublands at a given water availability, and thus had higher GEP/ET. Differences in GEP/ET were also related to the relative proportion of abiotic evaporation, estimated from the ET intercept in a linear regression of ET and GEP, to total ET at a site, highlighting the importance of ET partitioning for understanding how semiarid rainfall drives plant productivity.

WASP (Write a Scientific Paper) using Excel - 2: Pivot tables.

PubMed

Grech, Victor

2018-02-01

Data analysis at the descriptive stage and the eventual presentation of results requires the tabulation and summarisation of data. This exercise should always precede inferential statistics. Pivot tables and pivot charts are one of Excel's most powerful and underutilised features, with tabulation functions that immensely facilitate descriptive statistics. Pivot tables permit users to dynamically summarise and cross-tabulate data, create tables in several dimensions, offer a range of summary statistics and can be modified interactively with instant outputs. Large and detailed datasets are thereby easily manipulated making pivot tables arguably the best way to explore, summarise and present data from many different angles. This second paper in the WASP series in Early Human Development provides pointers for pivot table manipulation in Excel™. Copyright © 2018 Elsevier B.V. All rights reserved.

Functional outcomes of fungal community shifts driven by tree genotype and spatial-temporal factors in Mediterranean pine forests.

PubMed

Pérez-Izquierdo, Leticia; Zabal-Aguirre, Mario; Flores-Rentería, Dulce; González-Martínez, Santiago C; Buée, Marc; Rincón, Ana

2017-04-01

Fungi provide relevant ecosystem services contributing to primary productivity and the cycling of nutrients in forests. These fungal inputs can be decisive for the resilience of Mediterranean forests under global change scenarios, making necessary an in-deep knowledge about how fungal communities operate in these ecosystems. By using high-throughput sequencing and enzymatic approaches, we studied the fungal communities associated with three genotypic variants of Pinus pinaster trees, in 45-year-old common garden plantations. We aimed to determine the impact of biotic (i.e., tree genotype) and abiotic (i.e., season, site) factors on the fungal community structure, and to explore whether structural shifts triggered functional responses affecting relevant ecosystem processes. Tree genotype and spatial-temporal factors were pivotal structuring fungal communities, mainly by influencing their assemblage and selecting certain fungi. Diversity variations of total fungal community and of that of specific fungal guilds, together with edaphic properties and tree's productivity, explained relevant ecosystem services such as processes involved in carbon turnover and phosphorous mobilization. A mechanistic model integrating relations of these variables and ecosystem functional outcomes is provided. Our results highlight the importance of structural shifts in fungal communities because they may have functional consequences for key ecosystem processes in Mediterranean forests. © 2017 Society for Applied Microbiology and John Wiley and Sons Ltd.

Gaze cueing by pareidolia faces.

PubMed

Takahashi, Kohske; Watanabe, Katsumi

2013-01-01

Visual images that are not faces are sometimes perceived as faces (the pareidolia phenomenon). While the pareidolia phenomenon provides people with a strong impression that a face is present, it is unclear how deeply pareidolia faces are processed as faces. In the present study, we examined whether a shift in spatial attention would be produced by gaze cueing of face-like objects. A robust cueing effect was observed when the face-like objects were perceived as faces. The magnitude of the cueing effect was comparable between the face-like objects and a cartoon face. However, the cueing effect was eliminated when the observer did not perceive the objects as faces. These results demonstrated that pareidolia faces do more than give the impression of the presence of faces; indeed, they trigger an additional face-specific attentional process.

Gaze cueing by pareidolia faces

PubMed Central

Takahashi, Kohske; Watanabe, Katsumi

2013-01-01

Visual images that are not faces are sometimes perceived as faces (the pareidolia phenomenon). While the pareidolia phenomenon provides people with a strong impression that a face is present, it is unclear how deeply pareidolia faces are processed as faces. In the present study, we examined whether a shift in spatial attention would be produced by gaze cueing of face-like objects. A robust cueing effect was observed when the face-like objects were perceived as faces. The magnitude of the cueing effect was comparable between the face-like objects and a cartoon face. However, the cueing effect was eliminated when the observer did not perceive the objects as faces. These results demonstrated that pareidolia faces do more than give the impression of the presence of faces; indeed, they trigger an additional face-specific attentional process. PMID:25165505

DOE Office of Scientific and Technical Information (OSTI.GOV)

St-Onge, Denis A.

The two-dimensional Terry–Horton equation is shown to exhibit the Dimits shift when suitably modified to capture both the nonlinear enhancement of zonal/drift-wave interactions and the existence of residual Rosenbluth–Hinton states. This phenomenon persists through numerous simplifications of the equation, including a quasilinear approximation as well as a four-mode truncation. It is shown that the use of an appropriate adiabatic electron response, for which the electrons are not affected by the flux-averaged potential, results in anmore » $$\\boldsymbol{E}\\times \\boldsymbol{B}$$ nonlinearity that can efficiently transfer energy non-locally to length scales of the order of the sound radius. The size of the shift for the nonlinear system is heuristically calculated and found to be in excellent agreement with numerical solutions. The existence of the Dimits shift for this system is then understood as an ability of the unstable primary modes to efficiently couple to stable modes at smaller scales, and the shift ends when these stable modes eventually destabilize as the density gradient is increased. This non-local mechanism of energy transfer is argued to be generically important even for more physically complete systems.« less

Intrinsic motivation: how can it play a pivotal role in changing clinician behaviour?

PubMed

Nantha, Yogarabindranath Swarna

2013-01-01

In the light of an increasing healthcare burden, this paper seeks to offer insight about how intrinsic motivation could play a pivotal role in improving the pre-existing healthcare service delivery systems by altering clinician behaviour. The paper argues the case for four salient dimensions worth exploring through the lens of intrinsic motivation--non-financial incentives, positive affective states, organizational culture and prescribing quality. This article reviews literature from both social sciences and health management practices to provide rationale on how intrinsic motivational approaches could optimize healthcare service delivery systems. The scrutiny of the body of evidence leads to the assertion that there is neglect in the initiatives to reinforce intrinsic motivation as a method to address the ailing morale of doctors. This seems to have exacerbated negative outcomes that include job dissatisfaction, compromise in the quality of care and poor patient-doctor relationships. Diminution in positive affective states amongst doctors, largely controlled by intrinsic motivation, led to strained doctor-patient communication and poor quality of care. Barriers in a healthcare organizational culture that restricts autonomy and empowerment seem to directly undermine job satisfaction. The article argues that it is crucial to shift away from the conventional tendencies promoting tangible rewards. A more holistic approach should be adopted by conducting formal research into intrinsic motivation and how it could aid the formulation of policies tailored to meet the current demands of the healthcare system.

A Shift from a Pivotal to Supporting Role for the Growth-Associated Protein (GAP-43) in the Coordination of Axonal Structural and Functional Plasticity

PubMed Central

Holahan, Matthew R.

2017-01-01

In a number of animal species, the growth-associated protein (GAP), GAP-43 (aka: F1, neuromodulin, B-50, G50, pp46), has been implicated in the regulation of presynaptic vesicular function and axonal growth and plasticity via its own biochemical properties and interactions with a number of other presynaptic proteins. Changes in the expression of GAP-43 mRNA or distribution of the protein coincide with axonal outgrowth as a consequence of neuronal damage and presynaptic rearrangement that would occur following instances of elevated patterned neural activity including memory formation and development. While functional enhancement in GAP-43 mRNA and/or protein activity has historically been hypothesized as a central mediator of axonal neuroplastic and regenerative responses in the central nervous system, it does not appear to be the crucial substrate sufficient for driving these responses. This review explores the historical discovery of GAP-43 (and associated monikers), its transcriptional, post-transcriptional and post-translational regulation and current understanding of protein interactions and regulation with respect to its role in axonal function. While GAP-43 itself appears to have moved from a pivotal to a supporting factor, there is no doubt that investigations into its functions have provided a clearer understanding of the biochemical underpinnings of axonal plasticity. PMID:28912688

The Relationship between the Field-Shifting Phenomenon and Representational Coherence of Place Cells in CA1 and CA3 in a Cue-Altered Environment

ERIC Educational Resources Information Center

Lee, Inah; Knierim, James J.

2007-01-01

Subfields of the hippocampus display differential dynamics in processing a spatial environment, especially when changes are introduced to the environment. Specifically, when familiar cues in the environment are spatially rearranged, place cells in the CA3 subfield tend to rotate with a particular set of cues (e.g., proximal cues), maintaining a…

Cascading network failure across the Alzheimer’s disease spectrum

PubMed Central

Knopman, David S.; Gunter, Jeffrey L.; Graff-Radford, Jonathan; Vemuri, Prashanthi; Boeve, Bradley F.; Petersen, Ronald C.; Weiner, Michael W.; Jack, Clifford R.

2016-01-01

Abstract Complex biological systems are organized across various spatiotemporal scales with particular scientific disciplines dedicated to the study of each scale (e.g. genetics, molecular biology and cognitive neuroscience). When considering disease pathophysiology, one must contemplate the scale at which the disease process is being observed and how these processes impact other levels of organization. Historically Alzheimer’s disease has been viewed as a disease of abnormally aggregated proteins by pathologists and molecular biologists and a disease of clinical symptoms by neurologists and psychologists. Bridging the divide between these scales has been elusive, but the study of brain networks appears to be a pivotal inroad to accomplish this task. In this study, we were guided by an emerging systems-based conceptualization of Alzheimer’s disease and investigated changes in brain networks across the disease spectrum. The default mode network has distinct subsystems with unique functional-anatomic connectivity, cognitive associations, and responses to Alzheimer’s pathophysiology. These distinctions provide a window into the systems-level pathophysiology of Alzheimer’s disease. Using clinical phenotyping, metadata, and multimodal neuroimaging data from the Alzheimer’s Disease Neuroimaging Initiative, we characterized the pattern of default mode network subsystem connectivity changes across the entire disease spectrum (n = 128). The two main findings of this paper are (i) the posterior default mode network fails before measurable amyloid plaques and appears to initiate a connectivity cascade that continues throughout the disease spectrum; and (ii) high connectivity between the posterior default mode network and hubs of high connectivity (many located in the frontal lobe) is associated with amyloid accumulation. These findings support a system model best characterized by a cascading network failure—analogous to cascading failures seen in power grids triggered by local overloads proliferating to downstream nodes eventually leading to widespread power outages, or systems failures. The failure begins in the posterior default mode network, which then shifts processing burden to other systems containing prominent connectivity hubs. This model predicts a connectivity ‘overload’ that precedes structural and functional declines and recasts the interpretation of high connectivity from that of a positive compensatory phenomenon to that of a load-shifting process transiently serving a compensatory role. It is unknown whether this systems-level pathophysiology is the inciting event driving downstream molecular events related to synaptic activity embedded in these systems. Possible interpretations include that the molecular-level events drive the network failure, a pathological interaction between the network-level and the molecular-level, or other upstream factors are driving both. PMID:26586695

Silicon utilizing microorganisms in the sea act as the environmental bellwether which foretell future trends in weather fluctuations

NASA Astrophysics Data System (ADS)

Das, S.

2012-12-01

It is well known that the southerly shift of the Gulf Stream is associated with major storms, heavy rains and mudslide in the adjoining northern part of the globe. Phytoplanktons particularly their silicon utilizing members like diatoms were found to play a major part in this phenomenon. A decrease in silicon utilizing phytoplanktons and chlorophyll-a , which sometimes occurs even more than 10 fold was found associated with a parallel significant decrease of zooplanktons as reflected in the CPR survey, leads to fall of sea temperature causing a shift of the Gulf Stream. This sea temperature changes is also associated with cooling of the adjoining atmosphere in a remarkable way which leads to weather changes. The association of silicon utilizing diatoms and the ocean currents guides the future trends in the climatic swing known as NAO, one of the great fluctuations that occur in the global climate, the largest of which is the ENSO phenomenon in the Pacific Ocean, which cause destruction all around the tropics. When total density and biovolume of phytoplanktons were studied it was found that the changes of pennate diatoms was unique and occurred in an opposite way in comparison to green algae, blue green algae, chrysophyte, cryptophytes, dinoflagellates and green flagellates.

Role of Self-Association and Supersaturation in Oral Absorption of a Poorly Soluble Weakly Basic Drug.

PubMed

Narang, Ajit S; Badawy, Sherif; Ye, Qingmei; Patel, Dhaval; Vincent, Maria; Raghavan, Krishnaswamy; Huang, Yande; Yamniuk, Aaron; Vig, Balvinder; Crison, John; Derbin, George; Xu, Yan; Ramirez, Antonio; Galella, Michael; Rinaldi, Frank A

2015-08-01

Precipitation of weakly basic drugs in intestinal fluids can affect oral drug absorption. In this study, the implications of self-association of brivanib alaninate in acidic aqueous solution, leading to supersaturation at basic pH condition, on its solubility and oral absorption were investigated. Self-association of brivanib alaninate was investigated by proton NMR spectroscopy, surface tension measurement, dynamic light scattering, isothermal titration calorimetry, and molecular modeling. Drug solubility was determined in various pH media, and its tendency to supersaturate upon pH shift was investigated in buffered and biorelevant aqueous solutions. Pharmacokinetic modeling of human oral drug absorption was utilized for parameter sensitivity analyses of input variables. Brivanib alaninate exhibited continuous, and pH- and concentration-dependent self-association. This phenomenon resulted in positive deviation of drug solubility at acidic pH and the formation of a stable supersaturated drug solution in pH-shift assays. Consistent with the supersaturation phenomenon observed in vitro, oral absorption simulations necessitated invoking long precipitation time in the intestine to successfully predict in vivo data. Self-association of a weakly basic drug in acidic aqueous solution can increase its oral absorption by supersaturation and precipitation resistance at the intestinal pH. This consideration is important to the selection of parameters for oral absorption simulation.

Seasonally Varying Predation Behavior and Climate Shifts Are Predicted to Affect Predator-Prey Cycles.

PubMed

Tyson, Rebecca; Lutscher, Frithjof

2016-11-01

The functional response of some predator species changes from a pattern characteristic for a generalist to that for a specialist according to seasonally varying prey availability. Current theory does not address the dynamic consequences of this phenomenon. Since season length correlates strongly with altitude and latitude and is predicted to change under future climate scenarios, including this phenomenon in theoretical models seems essential for correct prediction of future ecosystem dynamics. We develop and analyze a two-season model for the great horned owl (Bubo virginialis) and snowshoe hare (Lepus americanus). These species form a predator-prey system in which the generalist to specialist shift in predation pattern has been documented empirically. We study the qualitative behavior of this predator-prey model community as summer season length changes. We find that relatively small changes in summer season length can have a profound impact on the system. In particular, when the predator has sufficient alternative resources available during the summer season, it can drive the prey to extinction, there can be coexisting stable states, and there can be stable large-amplitude limit cycles coexisting with a stable steady state. Our results illustrate that the impacts of global change on local ecosystems can be driven by internal system dynamics and can potentially have catastrophic consequences.

Evaluating a Pivot-Based Approach for Bilingual Lexicon Extraction

PubMed Central

Kim, Jae-Hoon; Kwon, Hong-Seok; Seo, Hyeong-Won

2015-01-01

A pivot-based approach for bilingual lexicon extraction is based on the similarity of context vectors represented by words in a pivot language like English. In this paper, in order to show validity and usability of the pivot-based approach, we evaluate the approach in company with two different methods for estimating context vectors: one estimates them from two parallel corpora based on word association between source words (resp., target words) and pivot words and the other estimates them from two parallel corpora based on word alignment tools for statistical machine translation. Empirical results on two language pairs (e.g., Korean-Spanish and Korean-French) have shown that the pivot-based approach is very promising for resource-poor languages and this approach observes its validity and usability. Furthermore, for words with low frequency, our method is also well performed. PMID:25983745

Preset pivotal tool holder

DOEpatents

Asmanes, Charles

1979-01-01

A tool fixture is provided for precise pre-alignment of a radiused edge cutting tool in a tool holder relative to a fixed reference pivot point established on said holder about which the tool holder may be selectively pivoted relative to the fixture base member to change the contact point of the tool cutting edge with a workpiece while maintaining the precise same tool cutting radius relative to the reference pivot point.

Variable Geometry Aircraft Wing Supported by Struts And/Or Trusses

NASA Technical Reports Server (NTRS)

Melton, John E. (Inventor); Dudley, Michael R. (Inventor)

2016-01-01

The present invention provides an aircraft having variable airframe geometry for accommodating efficient flight. The aircraft includes an elongated fuselage, an oblique wing pivotally connected with said fuselage, a wing pivoting mechanism connected with said oblique wing and said fuselage, and a brace operably connected between said oblique wing and said fuselage. The present invention also provides an aircraft having an elongated fuselage, an oblique wing pivotally connected with said fuselage, a wing pivoting mechanism connected with said oblique wing and said fuselage, a propulsion system pivotally connected with said oblique wing, and a brace operably connected between said propulsion system and said fuselage.

The effect of introspection on judgment and decision making is dependent on the quality of conscious thinking.

PubMed

Leisti, Tuomas; Häkkinen, Jukka

2016-05-01

That introspection may impair certain judgments and result in fabrication has been attributed to a distracting shift from more adaptive intuitive processing to more analytic and conscious processing. This phenomenon was studied in an experiment where participants made multidimensional visual choices. It was found that the effect of this shift on decision-making performance was dependent on the quality of the explanations during introspection, while the performance in silent conditions was not. Therefore, it appears that the effect of introspection on judgments is not only influenced by the thinking mode per se, but also by the individual's ability to approach the decision problem analytically. Copyright © 2016 Elsevier Inc. All rights reserved.

Light-driven changes in energy metabolism directly entrain the cyanobacterial circadian oscillator

PubMed Central

Rust, Michael J.; Golden, Susan S.; O'Shea, Erin K.

2012-01-01

Circadian clocks are self-sustained biological oscillators that can be entrained by environmental cues. Though this phenomenon has been studied in many organisms, the molecular mechanisms of entrainment remain unclear. Three cyanobacterial proteins and ATP are sufficient to generate oscillations in phosphorylation in vitro. We show that changes in illumination that induce a phase shift in cultured cyanobacteria also cause changes in the ATP/ADP ratio. When these nucleotide changes are simulated in the in vitro oscillator, they cause phase shifts similar to those observed in vivo. Physiological concentrations of ADP inhibit kinase activity in the oscillator and a mathematical model constrained by data shows that this effect is sufficient to quantitatively explain entrainment of the cyanobacterial circadian clock. PMID:21233390

Comparison of treatment effect sizes from pivotal and postapproval trials of novel therapeutics approved by the FDA based on surrogate markers of disease: a meta-epidemiological study.

PubMed

Wallach, Joshua D; Ciani, Oriana; Pease, Alison M; Gonsalves, Gregg S; Krumholz, Harlan M; Taylor, Rod S; Ross, Joseph S

2018-03-21

The U.S. Food and Drug Administration (FDA) often approves new drugs based on trials that use surrogate markers for endpoints, which involve certain trade-offs and may risk making erroneous inferences about the medical product's actual clinical effect. This study aims to compare the treatment effects among pivotal trials supporting FDA approval of novel therapeutics based on surrogate markers of disease with those observed among postapproval trials for the same indication. We searched Drugs@FDA and PubMed to identify published randomized superiority design pivotal trials for all novel drugs initially approved by the FDA between 2005 and 2012 based on surrogate markers as primary endpoints and published postapproval trials using the same surrogate markers or patient-relevant outcomes as endpoints. Summary ratio of odds ratios (RORs) and difference between standardized mean differences (dSMDs) were used to quantify the average difference in treatment effects between pivotal and matched postapproval trials. Between 2005 and 2012, the FDA approved 88 novel drugs for 90 indications based on one or multiple pivotal trials using surrogate markers of disease. Of these, 27 novel drugs for 27 indications were approved based on pivotal trials using surrogate markers as primary endpoints that could be matched to at least one postapproval trial, for a total of 43 matches. For nine (75.0%) of the 12 matches using the same non-continuous surrogate markers as trial endpoints, pivotal trials had larger treatment effects than postapproval trials. On average, treatment effects were 50% higher (more beneficial) in the pivotal than the postapproval trials (ROR 1.5; 95% confidence interval CI 1.01-2.23). For 17 (54.8%) of the 31 matches using the same continuous surrogate markers as trial endpoints, pivotal trials had larger treatment effects than the postapproval trials. On average, there was no difference in treatment effects between pivotal and postapproval trials (dSMDs 0.01; 95% CI -0.15-0.16). Many postapproval drug trials are not directly comparable to previously published pivotal trials, particularly with respect to endpoint selection. Although treatment effects from pivotal trials supporting FDA approval of novel therapeutics based on non-continuous surrogate markers of disease are often larger than those observed among postapproval trials using surrogate markers as trial endpoints, there is no evidence of difference between pivotal and postapproval trials using continuous surrogate markers.

Impact of response shift on the assessment of treatment effects using the Oral Health Impact Profile.

PubMed

Reissmann, Daniel R; Remmler, Antje; John, Mike T; Schierz, Oliver; Hirsch, Christian

2012-12-01

The assessment of changes in oral health-related quality of life (OHRQoL) is challenging because individuals' concepts and internal standards of OHRQoL may change over time. The aim of this study was to detect response shifts in OHRQoL assessments made using the Oral Health Impact Profile (OHIP). Oral health-related quality of life was assessed in a consecutive sample of 126 patients seeking prosthodontic care. Patients were asked to rate their OHRQoL before treatment started and 1 month after treatment was finished, using the German 49-item version of the OHIP. When rating their OHRQoL after treatment, patients were also asked to rate their pre-treatment OHRQoL without having access to their baseline data. The response shift was calculated as the difference in OHIP summary scores between the initial assessment and the retrospective baseline assessment. The OHIP mean scores decreased from 31.8 at the initial baseline assessment to 24.4 after treatment. The retrospective baseline assessment resulted in an OHIP mean score of 38.1, corresponding to a response shift of 6.3 OHIP points. The effect size (Cohen's d = 0.21) of the response shift was considered small. The response shift phenomenon and its magnitude have important implications for dental practice, where patients and dentists often assess perceived treatment effects retrospectively. © 2012 Eur J Oral Sci.

Dye shift: a neglected source of genotyping error in molecular ecology.

PubMed

Sutton, Jolene T; Robertson, Bruce C; Jamieson, Ian G

2011-05-01

Molecular ecologists must be vigilant in detecting and accounting for genotyping error, yet potential errors stemming from dye-induced mobility shift (dye shift) may be frequently neglected and largely unknown to researchers who employ 3-primer systems with automated genotyping. When left uncorrected, dye shift can lead to mis-scoring alleles and even to falsely calling new alleles if different dyes are used to genotype the same locus in subsequent reactions. When we used four different fluorophore labels from a standard dye set to genotype the same set of loci, differences in the resulting size estimates for a single allele ranged from 2.07 bp to 3.68 bp. The strongest effects were associated with the fluorophore PET, and relative degree of dye shift was inversely related to locus size. We found little evidence in the literature that dye shift is regularly accounted for in 3-primer studies, despite knowledge of this phenomenon existing for over a decade. However, we did find some references to erroneous standard correction factors for the same set of dyes that we tested. We thus reiterate the need for strict quality control when attempting to reduce possible sources of genotyping error, and in cases where different dyes are applied to a single locus, perhaps mistakenly, we strongly discourage researchers from assuming generic correction patterns. © 2011 Blackwell Publishing Ltd.

Voltage-sensing domain mode shift is coupled to the activation gate by the N-terminal tail of hERG channels.

PubMed

Tan, Peter S; Perry, Matthew D; Ng, Chai Ann; Vandenberg, Jamie I; Hill, Adam P

2012-09-01

Human ether-a-go-go-related gene (hERG) potassium channels exhibit unique gating kinetics characterized by unusually slow activation and deactivation. The N terminus of the channel, which contains an amphipathic helix and an unstructured tail, has been shown to be involved in regulation of this slow deactivation. However, the mechanism of how this occurs and the connection between voltage-sensing domain (VSD) return and closing of the gate are unclear. To examine this relationship, we have used voltage-clamp fluorometry to simultaneously measure VSD motion and gate closure in N-terminally truncated constructs. We report that mode shifting of the hERG VSD results in a corresponding shift in the voltage-dependent equilibrium of channel closing and that at negative potentials, coupling of the mode-shifted VSD to the gate defines the rate of channel closure. Deletion of the first 25 aa from the N terminus of hERG does not alter mode shifting of the VSD but uncouples the shift from closure of the cytoplasmic gate. Based on these observations, we propose the N-terminal tail as an adaptor that couples voltage sensor return to gate closure to define slow deactivation gating in hERG channels. Furthermore, because the mode shift occurs on a time scale relevant to the cardiac action potential, we suggest a physiological role for this phenomenon in maximizing current flow through hERG channels during repolarization.

Managing health worker migration: a qualitative study of the Philippine response to nurse brain drain

PubMed Central

2012-01-01

Background The emigration of skilled nurses from the Philippines is an ongoing phenomenon that has impacted the quality and quantity of the nursing workforce, while strengthening the domestic economy through remittances. This study examines how the development of brain drain-responsive policies is driven by the effects of nurse migration and how such efforts aim to achieve mind-shifts among nurses, governing and regulatory bodies, and public and private institutions in the Philippines and worldwide. Methods Interviews and focus group discussions were conducted to elicit exploratory perspectives on the policy response to nurse brain drain. Interviews with key informants from the nursing, labour and immigration sectors explored key themes behind the development of policies and programmes that respond to nurse migration. Focus group discussions were held with practising nurses to understand policy recipients’ perspectives on nurse migration and policy. Results Using the qualitative data, a thematic framework was created to conceptualize participants’ perceptions of how nurse migration has driven the policy development process. The framework demonstrates that policymakers have recognised the complexity of the brain drain phenomenon and are crafting dynamic policies and programmes that work to shift domestic and global mindsets on nurse training, employment and recruitment. Conclusions Development of responsive policy to Filipino nurse brain drain offers a glimpse into a domestic response to an increasingly prominent global issue. As a major source of professionals migrating abroad for employment, the Philippines has formalised efforts to manage nurse migration. Accordingly, the Philippine paradigm, summarised by the thematic framework presented in this paper, may act as an example for other countries that are experiencing similar shifts in healthcare worker employment due to migration. PMID:23249411

On the fog variability over south Asia

NASA Astrophysics Data System (ADS)

Syed, F. S.; Körnich, H.; Tjernström, M.

2012-12-01

An increasing trend in fog frequencies over south Asia during winter in the last few decades has resulted in large economical losses and has caused substantial difficulties in the daily lives of people. In order to better understand the fog phenomenon, we investigated the climatology, inter-annual variability and trends in the fog occurrence from 1976 to 2010 using observational data from 82 stations, well distributed over India and Pakistan. Fog blankets large area from Pakistan to Bangladesh across north India from west to east running almost parallel to south of the Himalayas. An EOF analysis revealed that the fog variability over the whole region is coupled and therefore must be governed by some large scale phenomenon on the inter-annual time scale. Significant positive trends were found in the fog frequency but this increase is not gradual, as with the humidity, but comprises of two distinct regimes shifts, in 1990 and 1998, with respect to both mean and variance. The fog is also detected in ERA-Interim 3 hourly, surface and model level forecast data when using the concept of "cross-over temperature" combined with boundary layer stability. This fog index is able to reproduce the regime shift around 1998 and shows that the method can be applied to analyze fog over south Asia. The inter-annual variability seems to be associated with the wave train originating from the North Atlantic in the upper troposphere that when causing higher pressure over the region results in an increased boundary layer stability and surface-near relative humidity. The trend and shifts in the fog occurrence seems to be associated with the gradual increasing trend in relative humidity from 1990 onwards.

Failure Analysis on Tail Rotor Teeter Pivot Bolt on a Helicopter

NASA Astrophysics Data System (ADS)

Qiang, WANG; Zi-long, DONG

2018-03-01

Tail rotor teeter pivot bolt of a helicopter fractured when in one flight. Failure analysis on the bolt was finished in laboratory. Macroscopic observation of the tailor rotor teeter pivot bolt, macro and microscopic inspection on the fracture surface of the bolt was carried out. Chemical components and metallurgical structure was also carried out. Experiment results showed that fracture mode of the tail rotor teeter pivot bolt is fatigue fracture. Fatigue area is over 80% of the total fracture surface, obvious fatigue band characteristics can be found at the fracture face. According to the results were analyzed from the macroscopic and microcosmic aspects, fracture reasons of the tail rotor teeter pivot bolt were analyzed in detail

Potential to increase active commuting level in university area (Case study: Universitas Gadjah Mada)

NASA Astrophysics Data System (ADS)

Devi, M. K.

2017-06-01

In order to alleviate the negative impacts of motorized vehicle use as well as create sustainable environment within campus area, it is pivotal to encourage mode shifting among university students. Active transport modes such as walking, cycling, and using public transport can be considered as alternative modes. This paper tried to identify the potential to increase active commuting in UGM by understanding student’s travel behavior. ANOVA test was employed to identify the perceptions between students across residential zones toward motivators and barriers to actively commute. The findings were used to propose strategies for increasing active commuting level in UGM, which are: reducing barriers to actively commute, improving public transport services, improving walking and cycling facilities, and introducing programs to discourage motorized vehicle use.

Stem cell metabolism in tissue development and aging

PubMed Central

Shyh-Chang, Ng; Daley, George Q.; Cantley, Lewis C.

2013-01-01

Recent advances in metabolomics and computational analysis have deepened our appreciation for the role of specific metabolic pathways in dictating cell fate. Once thought to be a mere consequence of the state of a cell, metabolism is now known to play a pivotal role in dictating whether a cell proliferates, differentiates or remains quiescent. Here, we review recent studies of metabolism in stem cells that have revealed a shift in the balance between glycolysis, mitochondrial oxidative phosphorylation and oxidative stress during the maturation of adult stem cells, and during the reprogramming of somatic cells to pluripotency. These insights promise to inform strategies for the directed differentiation of stem cells and to offer the potential for novel metabolic or pharmacological therapies to enhance regeneration and the treatment of degenerative disease. PMID:23715547

Expanding hegemonic masculinity: the use of irony in young men's stories about romantic experiences.

PubMed

Korobov, Neill

2009-12-01

This study examines the use of irony in young men's stories about romantic and sexual experiences. Because romantic experiences are central in the constitution of a heterosexual self, and because they are increasingly formulated in relation to traditional masculine norms and the simultaneous avowal and disavowal of effeminacy, they reveal an oscillation between complicity and resistance to hegemonic masculine norms. This oscillation is explored in stories about promiscuity, seduction, and vulnerability. Critical discursive analyses reveal how young men discursively pivot between complicity and resistance to traditional masculine norms, how this oscillation functions in the accomplishment of their romantic identities, how a sense of conventional masculinity is reclaimed, and what these processes reveal about the shifting nature of hegemonic masculinity in contemporary culture.

Ferroelectric thin film acoustic devices with electrical multiband switching ability.

PubMed

Ptashnik, Sergey V; Mikhailov, Anatoliy K; Yastrebov, Alexander V; Petrov, Peter K; Liu, Wei; Alford, Neil McN; Hirsch, Soeren; Kozyrev, Andrey B

2017-11-10

Design principles of a new class of microwave thin film bulk acoustic resonators with multiband resonance frequency switching ability are presented. The theory of the excitation of acoustic eigenmodes in multilayer ferroelectric structures is considered, and the principle of selectivity for resonator with an arbitrary number of ferroelectric layers is formulated. A so called "criterion function" is suggested that allows to determine the conditions for effective excitation at one selected resonance mode with suppression of other modes. The proposed theoretical approach is verifiedusing thepreexisting experimental data published elsewhere. Finally, the possible application of the two ferroelectric layers structures for switchable microwave overtone resonators, binary and quadrature phase-shift keying modulators are discussed. These devices could play a pivotal role in the miniaturization of microwave front-end antenna circuits.

Concept inventing: a humanbecoming perspective on suffering.

PubMed

Doucet, Thomas

2014-04-01

Sufferance is a universal living experience. In view of the humanbecoming theoretical perspective, concept inventing is a way to expand understanding about a phenomenon of interest and to contribute to nursing knowledge development. This column offers a synthetic definition of sufferance in light of the concept inventing process. Sufferance is anguishing turbulence in weaving the cherished arising with luminous shifting. At the theoretical level, sufferance is imaging in the valuing connecting-separating of transforming.

Local Cochlear Correlations of Perceived Pitch

NASA Astrophysics Data System (ADS)

Martignoli, Stefan; Stoop, Ruedi

2010-07-01

Pitch is one of the most salient attributes of the human perception of sound, but is still not well understood. This difficulty originates in the entwined nature of the phenomenon, in which a physical stimulus as well as a psychophysiological signal receiver are involved. In an electronic realization of a biophysically detailed nonlinear model of the cochlea, we find local cochlear correlates of the perceived pitch that explain all essential pitch-shifting phenomena from physical grounds.

Surface Information Loss in Comprehension

PubMed Central

Gernsbacher, Morton Ann

2014-01-01

Shortly after a sentence has been comprehended, information about its exact surface form (e.g., its word order) becomes less available. The present research demonstrated this phenomenon during the comprehension of nonverbal stimuli (picture stories). In Experiment 1, significantly more surface (left/right orientation) information was lost after comprehending several picture stories than just one; in Experiment 2, more was lost after comprehending an entire picture story than half of one. In Experiment 3, subjects segmented the picture stories into their constituents; in Experiment 4, significantly more surface information was lost after crossing these constituents’ boundaries than before. The present research also investigated why surface information is lost. Four explanations were considered: Surface information loss is the result of performing grammatical transformations (the linguistic hypothesis), exceeding short-term memory limitations (the memory limitations hypothesis), integrating information into gist (the integration hypothesis), shifting from building one substructure to initiating another (the processing shift hypothesis). The linguistic and memory limitations hypotheses were considered inadequate; the integration and the processing shift hypotheses were tested in the last set of experiments. In Experiment 5 (using nonverbal stimuli), the predictions made by the processing shift hypothesis were confirmed; in Experiment 6 (using verbal stimuli), these results were replicated. Other implications of the processing shift hypothesis concerning surface information loss are discussed. PMID:25308975

Adaptation Shifts Preferred Orientation of Tuning Curve in the Mouse Visual Cortex

PubMed Central

Jeyabalaratnam, Jeyadarshan; Bharmauria, Vishal; Bachatene, Lyes; Cattan, Sarah; Angers, Annie; Molotchnikoff, Stéphane

2013-01-01

In frontalized mammals it has been demonstrated that adaptation produces shift of the peak of the orientation tuning curve of neuron following frequent or lengthier presentation of a non-preferred stimulus. Depending on the duration of adaptation the shift is attractive (toward the adapter) or repulsive (away from the adapter). Mouse exhibits a salt-and-pepper cortical organization of orientation maps, hence this species may respond differently to adaptation. To examine this question, we determined the effect of twelve minutes of adaptation to one particular orientation on neuronal orientation tuning curves in V1 of anesthetized mice. Multi-unit activity of neurons in V1 was recorded in a conventional fashion. Cells were stimulated with sine-wave drifting gratings whose orientation tilted in steps. Results revealed that similarly to cats and monkeys, majority of cells shifted their optimal orientation in the direction of the adapter while a small proportion exhibited a repulsive shift. Moreover, initially untuned cells showing poor tuning curves reacted to adaptation by displaying sharp orientation selectivity. It seems that modification of the cellular property following adaptation is a general phenomenon observed in all mammals in spite of the different organization pattern of the visual cortex. This study is of pertinence to comprehend the mechanistic pathways of brain plasticity. PMID:23717586

Burst noise in the HAWAII-1RG multiplexer

NASA Astrophysics Data System (ADS)

Bacon, Candice M.; McMurtry, Craig W.; Pipher, Judith L.; Forrest, William J.; Garnett, James D.

2005-08-01

Burst noise (also known as popcorn noise and random telegraph signal/noise) is a phenomenon that is understood to be a result of defects in the vicinity of a p-n junction. It is characterized by rapid level shifts in both positive and negative directions and can have varying magnitudes. This noise has been seen in both HAWAII-1RG and HAWAII-2RG multiplexers and is under investigation. We have done extensive burst noise testing on a HAWAII-1RG multiplexer, where we have determined a significant percentage of pixels exhibit the phenomenon. In addition, the prevalence of small magnitude transitions make sensitivity of detection the main limiting factor. Since this is a noise source for the HAWAII-1RG multiplexer, its elimination would make the HAWAII-1RG and the HAWAII-2RG even lower noise multiplexers.

An Integrated Model of the Cardiovascular and Central Nervous Systems for Analysis of Microgravity Induced Fluid Redistribution

NASA Technical Reports Server (NTRS)

Price, R.; Gady, S.; Heinemann, K.; Nelson, E. S.; Mulugeta, L.; Ethier, C. R.; Samuels, B. C.; Feola, A.; Vera, J.; Myers, J. G.

2015-01-01

A recognized side effect of prolonged microgravity exposure is visual impairment and intracranial pressure (VIIP) syndrome. The medical understanding of this phenomenon is at present preliminary, although it is hypothesized that the headward shift of bodily fluids in microgravity may be a contributor. Computational models can be used to provide insight into the origins of VIIP. In order to further investigate this phenomenon, NASAs Digital Astronaut Project (DAP) is developing an integrated computational model of the human body which is divided into the eye, the cerebrovascular system, and the cardiovascular system. This presentation will focus on the development and testing of the computational model of an integrated model of the cardiovascular system (CVS) and central nervous system (CNS) that simulates the behavior of pressures, volumes, and flows within these two physiological systems.

Off-label drugs prescription in neonatology: a physician's duty or a medical hazardous attitude?

PubMed

d'Aloja, Ernesto; Paribello, Francesco; Demontis, Roberto; Müller, Mima

2011-10-01

The off-label and unlicensed use of drugs in neonatology is a widespread reality in all the NICUs. Several explanations may be given to justify the extension of this phenomenon and, among them, the lack of ad hoc clinical trials in neonatal subpopulation and the freedom to cure worldwide recognized to relatives and physicians. It is well known that adverse effects are more frequent, more serious and more underreported when medicines are used unauthorized or off-label, being physicians in theory responsible for the newborn physical damage. To avoid this responsibility, we believe that a shared legal framework may be helpful where the informative process on risks/benefits ratio for the newborn has a pivotal role. The National and International Scientific Societies should promote a common guidelines also for the informations on drug effects to be supplied to relatives. But at the same time EMA has to implement its strong policy towards the mandatory request on trials, for every new drug, on specific neonatal and pediatric subpopulations.

Intestinal barrier dysfunction in cirrhosis: Current concepts in pathophysiology and clinical implications

PubMed Central

Tsiaoussis, Georgios I; Assimakopoulos, Stelios F; Tsamandas, Athanassios C; Triantos, Christos K; Thomopoulos, Konstantinos C

2015-01-01

The intestinal lumen is a host place for a wide range of microbiota and sets a unique interplay between local immune system, inflammatory cells and intestinal epithelium, forming a physical barrier against microbial invaders and toxins. Bacterial translocation is the migration of viable or nonviable microorganisms or their pathogen-associated molecular patterns, such as lipopolysaccharide, from the gut lumen to the mesenteric lymph nodes, systemic circulation and other normally sterile extraintestinal sites. A series of studies have shown that translocation of bacteria and their products across the intestinal barrier is a commonplace in patients with liver disease. The deterioration of intestinal barrier integrity and the consulting increased intestinal permeability in cirrhotic patients play a pivotal pathophysiological role in the development of severe complications as high rate of infections, spontaneous bacterial peritonitis, hepatic encephalopathy, hepatorenal syndrome, variceal bleeding, progression of liver injury and hepatocellular carcinoma. Nevertheless, the exact cellular and molecular mechanisms implicated in the phenomenon of microbial translocation in liver cirrhosis have not been fully elucidated yet. PMID:26301048

Nonlinear focal shift beyond the geometrical focus in moderately focused acoustic beams.

PubMed

Camarena, Francisco; Adrián-Martínez, Silvia; Jiménez, Noé; Sánchez-Morcillo, Víctor

2013-08-01

The phenomenon of the displacement of the position along the axis of the pressure, intensity, and radiation force maxima of focused acoustic beams under increasing driving voltages (nonlinear focal shift) is studied for the case of a moderately focused beam. The theoretical and experimental results show the existence of this shift along the axis when the initial pressure in the transducer increases until the acoustic field reaches the fully developed nonlinear regime of propagation. Experimental data show that at high amplitudes and for moderate focusing, the position of the on-axis pressure maximum and radiation force maximum can surpass the geometrical focal length. On the contrary, the on-axis pressure minimum approaches the transducer under increasing driving voltages, increasing the distance between the positive and negative peak pressure in the beam. These results are in agreement with numerical KZK model predictions and the existed data of other authors and can be explained according to the effect of self-refraction characteristic of the nonlinear regime of propagation.

Re-construction of action awareness depends on an internal model of action-outcome timing.

PubMed

Stenner, Max-Philipp; Bauer, Markus; Machts, Judith; Heinze, Hans-Jochen; Haggard, Patrick; Dolan, Raymond J

2014-04-01

The subjective time of an instrumental action is shifted towards its outcome. This temporal binding effect is partially retrospective, i.e., occurs upon outcome perception. Retrospective binding is thought to reflect post-hoc inference on agency based on sensory evidence of the action - outcome association. However, many previous binding paradigms cannot exclude the possibility that retrospective binding results from bottom-up interference of sensory outcome processing with action awareness and is functionally unrelated to the processing of the action - outcome association. Here, we keep bottom-up interference constant and use a contextual manipulation instead. We demonstrate a shift of subjective action time by its outcome in a context of variable outcome timing. Crucially, this shift is absent when there is no such variability. Thus, retrospective action binding reflects a context-dependent, model-based phenomenon. Such top-down re-construction of action awareness seems to bias agency attribution when outcome predictability is low. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Re-construction of action awareness depends on an internal model of action-outcome timing

PubMed Central

Stenner, Max-Philipp; Bauer, Markus; Machts, Judith; Heinze, Hans-Jochen; Haggard, Patrick; Dolan, Raymond J.

2014-01-01

The subjective time of an instrumental action is shifted towards its outcome. This temporal binding effect is partially retrospective, i.e., occurs upon outcome perception. Retrospective binding is thought to reflect post-hoc inference on agency based on sensory evidence of the action – outcome association. However, many previous binding paradigms cannot exclude the possibility that retrospective binding results from bottom-up interference of sensory outcome processing with action awareness and is functionally unrelated to the processing of the action – outcome association. Here, we keep bottom-up interference constant and use a contextual manipulation instead. We demonstrate a shift of subjective action time by its outcome in a context of variable outcome timing. Crucially, this shift is absent when there is no such variability. Thus, retrospective action binding reflects a context-dependent, model-based phenomenon. Such top-down re-construction of action awareness seems to bias agency attribution when outcome predictability is low. PMID:24555983

Mental rotation impairs attention shifting and short-term memory encoding: neurophysiological evidence against the response-selection bottleneck model of dual-task performance.

PubMed

Pannebakker, Merel M; Jolicœur, Pierre; van Dam, Wessel O; Band, Guido P H; Ridderinkhof, K Richard; Hommel, Bernhard

2011-09-01

Dual tasks and their associated delays have often been used to examine the boundaries of processing in the brain. We used the dual-task procedure and recorded event-related potentials (ERPs) to investigate how mental rotation of a first stimulus (S1) influences the shifting of visual-spatial attention to a second stimulus (S2). Visual-spatial attention was monitored by using the N2pc component of the ERP. In addition, we examined the sustained posterior contralateral negativity (SPCN) believed to index the retention of information in visual short-term memory. We found modulations of both the N2pc and the SPCN, suggesting that engaging mechanisms of mental rotation impairs the deployment of visual-spatial attention and delays the passage of a representation of S2 into visual short-term memory. Both results suggest interactions between mental rotation and visual-spatial attention in capacity-limited processing mechanisms indicating that response selection is not pivotal in dual-task delays and all three processes are likely to share a common resource like executive control. Copyright © 2011 Elsevier Ltd. All rights reserved.

Nutrient stoichiometry and freshwater flow in shaping of phytoplankton population in a tropical monsoonal estuary (Kundalika Estuary)

NASA Astrophysics Data System (ADS)

Chowdhury, Mintu; Hardikar, Revati; Chanjaplackal Kesavan, Haridevi; Thomas, Jubin; Mitra, Aditi; Rokade, M. A.; Naidu, V. S.; Sukumaran, Soniya

2017-11-01

The present study aimed to understand the role of freshwater flow and physico-chemical parameters in influencing the phytoplankton community shift and thereby helping in balancing the ecosystem. The Kundalika estuary (KE) is a semi-diurnal tropical monsoonal estuary. Strong upstream currents during monsoon as assessed through a 2D numerical model influenced the succession of marine, estuarine and freshwater phytoplankton species depending on the extent of freshwater influx and its distribution in the estuary. Nitrogen and phosphorus played a pivotal role in regulating the phytoplankton growth and their proliferation. Distribution of different phytoplankton species in accordance to salinity and nutrient content was clearly observed. Among the four major classes (Diatoms, Dinoflagellates, Chlorophytes and Phytoflagellates) occurring in the KE, diatoms occupied a wide salinity range. Large-scale shifts in phytoplankton biomass and composition were associated with river run-off during monsoon. Phytoflagellates and Chlorophytes restricted their abundance to relatively high nitrogen level zones. Canonical Correspondence Analysis (CCA) between environmental variables and dominant taxa of phytoplankton indicated the influence of salinity on phytoplankton distribution in the estuarine precinct. Thus the freshwater influx in the KE played a major role on phytoplankton species diversity and its bloom potential.

Centrality and Flow Vergence gradient based Path analysis of scientific literature: A case study of Biotechnology for Engineering

NASA Astrophysics Data System (ADS)

Lathabai, Hiran H.; Prabhakaran, Thara; Changat, Manoj

2015-07-01

Biotechnology, ever since its inception has had a huge impact on the society and its various applications have been intricately woven into the human web of life. Its evolution amidst all the other research realms vital to mankind is remarkable. In this paper, we intend to identify the radical innovations in Biotechnology for Engineering using network analyses. Centrality analysis and Path analysis are used for identifying important works. Existence of Flow Vergence effect in the scientific literature is revealed. Flow Vergence gradient, an arc metric derived from FV model, is utilised for Path analysis which detects pivotal papers of paradigm shift more accurately. A major paradigm shift has been identified in the business models of Biotechnology for Engineering - 'Capability to Connectivity' model. Evidence towards the adoption of business practices in BT firms by nanotechnology start-ups is also identified. The notion of critical divergence is introduced and the exhibition of interdisciplinary interaction in emerging fields due to critical divergence is discussed. Implications of above analyses which target: (i) Science and technology policy makers, (ii) industrialists and investors, (iii) researchers in academia as well as industry, are also discussed.

Clinical handover as an interactive event: informational and interactional communication strategies in effective shift-change handovers.

PubMed

Eggins, Suzanne; Slade, Diana

2012-01-01

Clinical handover -- the transfer between clinicians of responsibility and accountability for patients and their care (AMA 2006) -- is a pivotal and high-risk communicative event in hospital practice. Studies focusing on critical incidents, mortality, risk and patient harm in hospitals have highlighted ineffective communication -- including incomplete and unstructured clinical handovers -- as a major contributing factor (NSW Health 2005; ACSQHC 2010). In Australia, as internationally, Health Departments and hospital management have responded by introducing standardised handover communication protocols. This paper problematises one such protocol - the ISBAR tool - and argues that the narrow understanding of communication on which such protocols are based may seriously constrain their ability to shape effective handovers. Based on analysis of audio-recorded shift-change clinical handovers between medical staff we argue that handover communication must be conceptualised as inherently interactive and that attempts to describe, model and teach handover practice must recognise both informational and interactive communication strategies. By comparing the communicative performance of participants in authentic handover events we identify communication strategies that are more and less likely to lead to an effective handover and demonstrate the importance of focusing close up on communication to improve the quality and safety of healthcare interactions.

Diet-induced changes of redox potential underlie compositional shifts in the rumen archaeal community.

PubMed

Friedman, Nir; Shriker, Eran; Gold, Ben; Durman, Thomer; Zarecki, Raphy; Ruppin, Eytan; Mizrahi, Itzhak

2017-01-01

Dietary changes are known to affect gut community structure, but questions remain about the mechanisms by which diet induces shifts in microbiome membership. Here, we addressed these questions in the rumen microbiome ecosystem - a complex microbial community that resides in the upper digestive tract of ruminant animals and is responsible for the degradation of the ingested plant material. Our dietary intervention experiments revealed that diet affects the most abundant taxa within the microbiome and that a specific group of methanogenic archaea of the order Methanomicrobiales is highly sensitive to its changes. Using metabolomic analyses together with in vitro microbiology approaches and whole-genome sequencing of Methanomicrobium mobile, a key species within this group, we identified that redox potential changes with diet and is the main factor that causes these dietary induced alternations in this taxa's abundance. Our genomic analysis suggests that the redox potential effect stems from a reduced number of anti-reactive oxygen species proteins coded in this taxon's genome. Our study highlights redox potential as a pivotal factor that could serve as a sculpturing force of community assembly within anaerobic gut microbial communities. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.

The origin of modern crocodyliforms: new evidence from the Cretaceous of Australia

PubMed Central

Salisbury, Steven W; Molnar, Ralph E; Frey, Eberhard; Willis, Paul M.A

2006-01-01

While the crocodyliform lineage extends back over 200 million years (Myr) to the Late Triassic, modern forms—members of Eusuchia—do not appear until the Cretaceous. Eusuchia includes the crown group Crocodylia, which comprises Crocodyloidea, Alligatoroidea and Gavialoidea. Fossils of non-crocodylian eusuchians are currently rare and, in most instances, fragmentary. Consequently, the transition from Neosuchia to Crocodylia has been one of the most poorly understood areas of crocodyliform evolution. Here we describe a new crocodyliform from the mid-Cretaceous (98–95 Myr ago; Albian–Cenomanian) Winton Formation of Queensland, Australia, as the most primitive member of Eusuchia. The anatomical changes associated with the emergence of this taxon indicate a pivotal shift in the feeding and locomotor behaviour of crocodyliforms—a shift that may be linked to the subsequent rapid diversification of Eusuchia 20 Myr later during the Late Cretaceous and Early Tertiary. While Laurasia (in particular North America) is the most likely ancestral area for Crocodylia, the biogeographic events associated with the origin of Eusuchia are more complex. Although the fossil evidence is limited, it now seems likely that at least part of the early history of Eusuchia transpired in Gondwana. PMID:16959633

Connectivity between mPFC and PCC predicts post-choice attitude change: The self-referential processing hypothesis of choice justification.

PubMed

Tompson, Steven; Chua, Hannah Faye; Kitayama, Shinobu

2016-11-01

Prior research shows that after making a choice, decision makers shift their attitudes in a choice-congruous direction. Although this post-choice attitude change effect is robust, the neural mechanisms underlying it are poorly understood. Here, we tested the hypothesis that decision makers elaborate on their choice in reference to self-knowledge to justify the choice they have made. This self-referential processing of the choice is thought to play a pivotal role in the post-choice attitude change. Twenty-four young American adults made a series of choices. They also rated their attitudes toward the choice options before and after the choices. In support of the current hypothesis, we found that changes in functional connectivity between two putative self-regions (medial prefrontal cortex and posterior cingulate cortex/precuneus]) during the post-choice (vs. pre-choice) rating of the chosen options predicted the post-choice shift of the attitudes toward the chosen options. This finding is the first to suggest that cognitive integration of various self-relevant cognitions is instrumental in fostering post-choice attitude change. Hum Brain Mapp 37:3810-3820, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Clinical Outcome of Medial Pivot Compared With Press-Fit Condylar Sigma Cruciate-Retaining Mobile-Bearing Total Knee Arthroplasty.

PubMed

Kim, Young-Hoo; Park, Jang-Won; Kim, Jun-Shik

2017-10-01

The purpose of this study was to compare the long-term clinical results, radiographic results, range of knee motion, patient satisfaction, and the survival rate of Medial-Pivot posterior cruciate-substituting, knee prosthesis and a press-fit condylar (PFC) Sigma cruciate-retaining mobile-bearing knee prosthesis in the same patients. One hundred eighty-two patients received Medial-Pivot knee prosthesis in one knee and a PFC Sigma knee prosthesis in the contralateral knee. The minimum duration of follow-up was 11 years (range, 11-12.6 years). The knees with a Medial-Pivot knee prosthesis had significantly worse results than those with a PFC Sigma knee prosthesis at the final follow-up with regard to the mean postoperative Knee Society knee scores (90 compared with 95 points), Western Ontario and McMaster Universities Osteoarthritis Index score (25 compared with 18 points), and range of knee motion (117° compared with 128°). Patients were more satisfied with PFC Sigma knee prosthesis (93%) than with Medial-Pivot knee prosthesis (75%). Complication rates were significantly higher in the Medial-Pivot knee group (26%) than those in the PFC Sigma knee group (6.5%). Radiographic results and survival rates (99% compared with 99.5%) were similar between the 2 groups. Although the long-term fixation and survival rate of both Medial-Pivot and PFC Sigma prostheses were similar, we observed a worse knee score, worse range of knee motion, and patient satisfaction was less in the Medial-Pivot knee group than in the PFC Sigma knee group. Furthermore, complication rate was also higher in the Medial-Pivot knee group than the other group. Copyright © 2017 Elsevier Inc. All rights reserved.

Temporal and phylogenetic evolution of the sauropod dinosaur body plan

NASA Astrophysics Data System (ADS)

Bates, Karl T.; Mannion, Philip D.; Falkingham, Peter L.; Brusatte, Stephen L.; Hutchinson, John R.; Otero, Alejandro; Sellers, William I.; Sullivan, Corwin; Stevens, Kent A.; Allen, Vivian

2016-03-01

The colossal size and body plan of sauropod dinosaurs are unparalleled in terrestrial vertebrates. However, to date, there have been only limited attempts to examine temporal and phylogenetic patterns in the sauropod bauplan. Here, we combine three-dimensional computational models with phylogenetic reconstructions to quantify the evolution of whole-body shape and body segment properties across the sauropod radiation. Limitations associated with the absence of soft tissue preservation in fossils result in large error bars about mean absolute body shape predictions. However, applying any consistent skeleton : body volume ratio to all taxa does yield changes in body shape that appear concurrent with major macroevolutionary events in sauropod history. A caudad shift in centre-of-mass (CoM) in Middle Triassic Saurischia, associated with the evolution of bipedalism in various dinosaur lineages, was reversed in Late Triassic sauropodomorphs. A craniad CoM shift coincided with the evolution of quadrupedalism in the Late Triassic, followed by a more striking craniad shift in Late Jurassic-Cretaceous titanosauriforms, which included the largest sauropods. These craniad CoM shifts are strongly correlated with neck enlargement, a key innovation in sauropod evolution and pivotal to their gigantism. By creating a much larger feeding envelope, neck elongation is thought to have increased feeding efficiency and opened up trophic niches that were inaccessible to other herbivores. However, we find that relative neck size and CoM position are not strongly correlated with inferred feeding habits. Instead the craniad CoM positions of titanosauriforms appear closely linked with locomotion and environmental distributions, potentially contributing to the continued success of this group until the end-Cretaceous, with all other sauropods having gone extinct by the early Late Cretaceous.

Temporal and phylogenetic evolution of the sauropod dinosaur body plan

PubMed Central

Bates, Karl T.; Mannion, Philip D.; Falkingham, Peter L.; Brusatte, Stephen L.; Hutchinson, John R.; Otero, Alejandro; Sellers, William I.; Sullivan, Corwin; Stevens, Kent A.; Allen, Vivian

2016-01-01

The colossal size and body plan of sauropod dinosaurs are unparalleled in terrestrial vertebrates. However, to date, there have been only limited attempts to examine temporal and phylogenetic patterns in the sauropod bauplan. Here, we combine three-dimensional computational models with phylogenetic reconstructions to quantify the evolution of whole-body shape and body segment properties across the sauropod radiation. Limitations associated with the absence of soft tissue preservation in fossils result in large error bars about mean absolute body shape predictions. However, applying any consistent skeleton : body volume ratio to all taxa does yield changes in body shape that appear concurrent with major macroevolutionary events in sauropod history. A caudad shift in centre-of-mass (CoM) in Middle Triassic Saurischia, associated with the evolution of bipedalism in various dinosaur lineages, was reversed in Late Triassic sauropodomorphs. A craniad CoM shift coincided with the evolution of quadrupedalism in the Late Triassic, followed by a more striking craniad shift in Late Jurassic–Cretaceous titanosauriforms, which included the largest sauropods. These craniad CoM shifts are strongly correlated with neck enlargement, a key innovation in sauropod evolution and pivotal to their gigantism. By creating a much larger feeding envelope, neck elongation is thought to have increased feeding efficiency and opened up trophic niches that were inaccessible to other herbivores. However, we find that relative neck size and CoM position are not strongly correlated with inferred feeding habits. Instead the craniad CoM positions of titanosauriforms appear closely linked with locomotion and environmental distributions, potentially contributing to the continued success of this group until the end-Cretaceous, with all other sauropods having gone extinct by the early Late Cretaceous. PMID:27069652

Pivotal Response Training. What Works Clearinghouse Intervention Report

ERIC Educational Resources Information Center

What Works Clearinghouse, 2016

2016-01-01

This intervention report presents findings from a systematic review of "pivotal response training" conducted using the What Works Clearinghouse Procedures and Standards Handbook (version 3.0) and the Children and Students with an Autism Spectrum Disorder review protocol (version 3.0). "Pivotal response training"…

The Efficiency of Small Bearings in Instruments of the Type Used in Aircraft

NASA Technical Reports Server (NTRS)

Norton, F H

1921-01-01

This report deals with the construction and properties of bearings and pivots for use in instruments. The static and running friction for both thrust and radial loads was determined for a number of conical pivots and cylindrical and ball bearings. The static rocking friction was also measured for several conical and ball bearings under a heavy load, especially to determine their suitability for use in N. P. L. (National Physical Laboratory) type wind tunnel balance. In constructing conical pivots and sockets it was found that the pivots should be hardened and highly polished, preferably with a revolving lap, and that the sockets should be made by punching with a hardened and polished punch. It was found that for a light load the conical pivots give less friction than any other type, and their wearing qualities when hardened are excellent. Very small ball bearings are unsatisfactory because the proportional accuracy of the balls and races is not high enough to insure smooth running. For rocking pivots under heavy loads it was found that a ball-and-socket bearing, consisting of a hemispherical socket and a sphere of smaller diameter concentric with it, with a row of small balls resting between the two, was superior to a pivot resting in a socket. It was found that vibration such as occurs in an airplane will greatly reduce the static friction of a pivot or bearing, in some cases to as little as one-twentieth of its static value.

Mechanical mechanisms of the directional shift and inverse of the eccentric compound droplet

NASA Astrophysics Data System (ADS)

Wang, Jingtao; Xu, Shen; Huang, Yan; Guan, Jing

2018-04-01

Mechanical mechanisms of the directional movement and inverse of an eccentric compound droplet in a modest extensional flow are investigated in this paper by spectral boundary element methods. In this work, a phenomenon is revealed that the shift of a compound droplet is driven by the asymmetric interfacial curvature, not just the outer drag. The asymmetric layout of the daughter droplet leads to the asymmetric drags from the continuous phase and the asymmetric deformation of the compound droplet with different interface curvatures. As the inner droplet has both enhancing and suppressing effects on the globule deformation (during different stages), the interface curvatures will vary when the relative size and location of the inner droplet are changed. The curvature difference results in the asymmetric pressure distribution and circulation inside the compound droplet. Eventually, the interaction of the inner driving force (curvature difference) and the outer drags results in the directional shift and inverse of the compound droplet. The shift direction is affected by the structural asymmetry parameter ɛ (eccentricity) and some flow features such as the capillary number. The conclusion could enlighten potential applications for the movement of soft globules driven by the curvature difference.

Nonlinear rocket motor stability prediction: Limit amplitude, triggering, and mean pressure shifta)

NASA Astrophysics Data System (ADS)

Flandro, Gary A.; Fischbach, Sean R.; Majdalani, Joseph

2007-09-01

High-amplitude pressure oscillations in solid propellant rocket motor combustion chambers display nonlinear effects including: (1) limit cycle behavior in which the fluctuations may dwell for a considerable period of time near their peak amplitude, (2) elevated mean chamber pressure (DC shift), and (3) a triggering amplitude above which pulsing will cause an apparently stable system to transition to violent oscillations. Along with the obvious undesirable vibrations, these features constitute the most damaging impact of combustion instability on system reliability and structural integrity. The physical mechanisms behind these phenomena and their relationship to motor geometry and physical parameters must, therefore, be fully understood if instability is to be avoided in the design process, or if effective corrective measures must be devised during system development. Predictive algorithms now in use have limited ability to characterize the actual time evolution of the oscillations, and they do not supply the motor designer with information regarding peak amplitudes or the associated critical triggering amplitudes. A pivotal missing element is the ability to predict the mean pressure shift; clearly, the designer requires information regarding the maximum chamber pressure that might be experienced during motor operation. In this paper, a comprehensive nonlinear combustion instability model is described that supplies vital information. The central role played by steep-fronted waves is emphasized. The resulting algorithm provides both detailed physical models of nonlinear instability phenomena and the critically needed predictive capability. In particular, the origin of the DC shift is revealed.

Associated lateral/medial knee instability and its relevant factors in anterior cruciate ligament-injured knees.

PubMed

Yuuki, Arata; Muneta, Takeshi; Ohara, Toshiyuki; Sekiya, Ichiro; Koga, Hideyuki

2017-03-01

Associations of lateral/medial knee instability with anterior cruciate ligament (ACL) injury have not been thoroughly investigated. The purposes of this study were to investigate whether lateral/medial knee instability is associated with ACL injury, and to clarify relevant factors for lateral/medial knee instability in ACL-injured knees. One hundred and nineteen patients with unilateral ACL-injured knees were included. Lateral/medial knee instability was assessed with varus/valgus stress X-ray examination for both injured and uninjured knees by measuring varus/valgus angle, lateral/medial joint opening, and lateral/medial joint opening index. Manual knee instability tests for ACL were evaluated to investigate associations between lateral/medial knee instability and anterior and/or rotational instabilities. Patients' backgrounds were evaluated to identify relevant factors for lateral/medial knee instability. Damage on the lateral collateral ligament (LCL) on MRI was also evaluated. All parameters regarding lateral knee instability in injured knees were significantly greater than in uninjured knees. There were significant correlations between lateral knee instability and the Lachman test as well as the pivot shift test. Patients with LCL damage had significantly greater lateral joint opening than those without LCL damage on MRI. Sensitivity of LCL damage on MRI to lateral joint opening was 100%, while its specificity was 36%. No other relevant factors were identified. In medial knee instability, there were also correlations between medial knee instability and the Lachman test/pivot shift test. However, the correlations were weak and other parameters were not significant. Lateral knee instability was greater in ACL-deficient knees than in uninjured knees. Lateral knee instability was associated with ACL-related instabilities as well as LCL damage on MRI, whereas MRI had low specificity to lateral knee instability. On the other hand, the association of medial knee instability on ACL-related instability was less than that of lateral knee instability. Level IV, case series with no comparison group. Copyright © 2016 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.

Turning points in international labor migration: a case study of Thailand.

PubMed

Vasuprasat, P

1994-01-01

"This article describes the dynamics of the structural transformation of the Thai economy, labor migration and direct foreign investment and proposes an econometric model to explain the migration phenomenon. Though migration shifts have been significantly influenced by political factors such as the Gulf crisis and tensions with Saudi Arabia, economic factors such as the Thai government's liberalization of markets and the expansion of trade and direct foreign investment have contributed to changes in labor market needs. The economic conditions of a shift from net exporter to net importer for labor are posited in the model. The empirical results reveal a turning point in labor migration from Thailand and also confirm the contribution of commodity export in place of labor export in creating employment and income." excerpt

ac Stark-mediated quantum control with femtosecond two-color laser pulses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Serrat, Carles

2005-11-15

A critical dependence of the quantum interference on the optical Stark spectral shift produced when two-color laser pulses interact with a two-level medium is observed. The four-wave mixing of two ultrashort phase-locked {omega}-3{omega} laser pulses propagating coherently in a two-level system depends on the pulses' relative phase. The phase dominating the efficiency of the coupling to the anti-Stokes Raman component is found to be determined by the sign of the total ac Stark shift induced in the system, in such a way that the phase sensitivity disappears precisely where the ac Stark effect due to both pulses is compensated. Amore » coherent control scheme based on this phenomenon can be contemplated as the basis for nonlinear optical spectroscopy techniques.« less

Algorithm based on regional separation for automatic grain boundary extraction using improved mean shift method

NASA Astrophysics Data System (ADS)

Zhenying, Xu; Jiandong, Zhu; Qi, Zhang; Yamba, Philip

2018-06-01

Metallographic microscopy shows that the vast majority of metal materials are composed of many small grains; the grain size of a metal is important for determining the tensile strength, toughness, plasticity, and other mechanical properties. In order to quantitatively evaluate grain size in metals, grain boundaries must be identified in metallographic images. Based on the phenomenon of grain boundary blurring or disconnection in metallographic images, this study develops an algorithm based on regional separation for automatically extracting grain boundaries by an improved mean shift method. Experimental observation shows that the grain boundaries obtained by the proposed algorithm are highly complete and accurate. This research has practical value because the proposed algorithm is suitable for grain boundary extraction from most metallographic images.

Assessing the high frequency behavior of non-polarizable electrodes for spectral induced polarization measurements

NASA Astrophysics Data System (ADS)

Abdulsamad, Feras; Florsch, Nicolas; Schmutz, Myriam; Camerlynck, Christian

2016-12-01

During the last decades, the usage of spectral induced polarization (SIP) measurements in hydrogeology and detecting environmental problems has been extensively increased. However, the physical mechanisms which are responsible for the induced polarization response over the usual frequency range (typically 1 mHz to 10-20 kHz) require better understanding. The phase shift observed at high frequencies is sometimes attributed to the so-called Maxwell-Wagner polarization which takes place when charges cross an interface. However, SIP measurements of tap water show a phase shift at frequencies higher than 1 kHz, where no Maxwell-Wagner polarization may occur. In this paper, we enlighten the possible origin of this phase shift and deduce its likely relationship with the types of the measuring electrodes. SIP Laboratory measurements of tap water using different types of measuring electrodes (polarizable and non-polarizable electrodes) are carried out to detect the origin of the phase shift at high frequencies and the influence of the measuring electrodes types on the observed complex resistivity. Sodium chloride is used to change the conductivity of the medium in order to quantify the solution conductivity role. The results of these measurements are clearly showing the impact of the measuring electrodes type on the measured phase spectrum while the influence on the amplitude spectrum is negligible. The phenomenon appearing on the phase spectrum at high frequency (> 1 kHz) whatever the electrode type is, the phase shows an increase compared to the theoretical response, and the discrepancy (at least in absolute value) increases with frequency, but it is less severe when medium conductivity is larger. Additionally, the frequency corner is shifted upward in frequency. The dependence of this phenomenon on the conductivity and the measuring electrodes type (electrode-electrolyte interface) seems to be due to some dielectric effects (as an electrical double layer of small relaxation time formed at the electrodes interface). Therefore, this dielectric response should be taken into account at high frequency to better analytically separate the medium own response from that linked to the measuring electrodes used. We modeled this effect by adding a capacitance connected in parallel with the traditional equivalent electric circuit used to describe the dielectric response of medium.

The Greek-Turkish Rapprochement Process, 1999-2004: Paradigm Shift or Epi-phenomenon

DTIC Science & Technology

2004-12-01

ke y U ni te d K in gd om T ot al N A T O E ur op e C an ad a U ni te d S ta te s T ot al N or th A m er ic a To ta l N A T O 1980 1990 2001... C . METHODOLOGY AND SOURCES...................................................... 4 D. SIGNIFICANCE...13 b. Gradual Reciprocation in Tension Reduction .......... 14 C . STATES’ COOPERATION AND

Molecular Self-Assembly of Group 11 Pyrazolate Complexes as Phosphorescent Chemosensors for Detection of Benzene

NASA Astrophysics Data System (ADS)

Ghazalli, N. F.; Yuliati, L.; Lintang, H. O.

2018-01-01

We highlight the systematic study on vapochromic sensing of aromatic vapors such as benzene using phosphorescent trinuclear pyrazolate complexes (2) with supramolecular assembly of a weak intermolecular metal-metal interaction consisting of 4-(3,5-dimethoxybenzyl)-3,5-dimethyl pyrazole ligand (1) and group 11 metal ions (Cu(I), Ag(I), Au(I)). The resulting chemosensor 2(Cu) revealed positive response to benzene vapors in 5 mins by blue-shifting its emission band in 44 nm (from 616 to 572 nm) and emitted bright orange to green, where this change cannot be recovered even with external stimuli. Comparing to 2(Ag) with longer metal-metal distance (473 nm) with same sensing time and quenching in 37%, 2(Au) gave quenching in 81% from its original intensity at 612 nm with reusability in 82% without external stimuli and emitted less emissive of red-orange from its original color. The shifting phenomenon in 2(Cu) suggests diffusion of benzene vapors to inside molecules for formation of intermolecular interaction with Cu(I)-Cu(I) interaction while quenching phenomenon in 2(Au) suggests diffusion of benzene vapors to between the Au(I)-Au(I) interaction. These results indicate that suitable molecular structure of ligand and metal ion in pyrazolate complex is important for designing chemosensor in the detection of benzene vapors.

Pivoting-Head Wrench

NASA Technical Reports Server (NTRS)

Bradley, Glen L.

1993-01-01

Wrench ends pivot so it can be used to loosen or tighten nuts or bolts in confined spaces. One end equipped with open-end socket; other end, with double-hexagon socket. Heads pivot on pins. Pins fit tightly so heads do not flop; friction on pins sufficient to hold heads in positions until rotated intentionally.

A sustainable model for training teachers to use pivotal response training.

PubMed

Suhrheinrich, Jessica

2015-08-01

The increase in the rate of autism diagnoses has created a growing demand for teachers who are trained to use effective interventions. The train-the-trainer model, which involves training supervisors to train others, may be ideal for providing cost-effective training and ongoing support to teachers. Although research supports interventions, such as pivotal response training, as evidence-based, dissemination to school environments has been problematic. This study assessed the benefits of using the train-the-trainer model to disseminate pivotal response training to school settings. A multiple-baseline design was conducted across three training groups, each consisting of one school staff member (trainer), three special education teachers, and six students. Trainers conducted the teacher-training workshop with high adherence to training protocol and met mastery criteria in their ability to implement pivotal response training, assess implementation of pivotal response training, and provide feedback to teachers. Six of the nine teachers mastered all components of pivotal response training. The remaining three teachers implemented 89% of the pivotal response training components correctly. The majority of trainers and teachers maintained their abilities at follow-up. These results support the use of the train-the-trainer model as an effective method of disseminating evidence-based practices in school settings. © The Author(s) 2014.

Efficient Execution Methods of Pivoting for Bulk Extraction of Entity-Attribute-Value-Modeled Data

PubMed Central

Luo, Gang; Frey, Lewis J.

2017-01-01

Entity-attribute-value (EAV) tables are widely used to store data in electronic medical records and clinical study data management systems. Before they can be used by various analytical (e.g., data mining and machine learning) programs, EAV-modeled data usually must be transformed into conventional relational table format through pivot operations. This time-consuming and resource-intensive process is often performed repeatedly on a regular basis, e.g., to provide a daily refresh of the content in a clinical data warehouse. Thus, it would be beneficial to make pivot operations as efficient as possible. In this paper, we present three techniques for improving the efficiency of pivot operations: 1) filtering out EAV tuples related to unneeded clinical parameters early on; 2) supporting pivoting across multiple EAV tables; and 3) conducting multi-query optimization. We demonstrate the effectiveness of our techniques through implementation. We show that our optimized execution method of pivoting using these techniques significantly outperforms the current basic execution method of pivoting. Our techniques can be used to build a data extraction tool to simplify the specification of and improve the efficiency of extracting data from the EAV tables in electronic medical records and clinical study data management systems. PMID:25608318

PiVoT GPS Receiver

NASA Technical Reports Server (NTRS)

Wennersten, Miriam Dvorak; Banes, Anthony Vince; Boegner, Gregory J.; Dougherty, Lamar; Edwards, Bernard L.; Roman, Joseph; Bauer, Frank H. (Technical Monitor)

2001-01-01

NASA Goddard Space Flight Center has built an open architecture, 24 channel space flight GPS receiver. The CompactPCI PiVoT GPS receiver card is based on the Mitel/GEC Plessey Builder-2 board. PiVoT uses two Plessey 2021 correlators to allow tracking of up to 24 separate GPS SV's on unique channels. Its four front ends can support four independent antennas, making it a useful card for hosting GPS attitude determination algorithms. It has been built using space quality, radiation tolerant parts. The PiVoT card will track a weaker signal than the original Builder 2 board. It also hosts an improved clock oscillator. The PiVoT software is based on the original Plessey Builder 2 software ported to the Linux operating system. The software is POSIX complaint and can easily be converted to other POSIX operating systems. The software is open source to anyone with a licensing agreement with Plessey. Additional tasks can be added to the software to support GPS science experiments or attitude determination algorithms. The next generation PiVoT receiver will be a single radiation hardened CompactPCI card containing the microprocessor and the GPS receiver optimized for use above the GPS constellation. PiVoT was flown successfully on a balloon in July, 2001, for its first non-simulated flight.

Metabostemness: a new cancer hallmark.

PubMed

Menendez, Javier A; Alarcón, Tomás

2014-01-01

The acquisition of and departure from stemness in cancer tissues might not only be hardwired by genetic controllers, but also by the pivotal regulatory role of the cellular metabotype, which may act as a "starter dough" for cancer stemness traits. We have coined the term metabostemness to refer to the metabolic parameters causally controlling or functionally substituting the epitranscriptional orchestration of the genetic reprograming that redirects normal and tumor cells toward less-differentiated cancer stem cell (CSC) cellular states. Certain metabotypic alterations might operate as pivotal molecular events rendering a cell of origin susceptible to epigenetic rewiring required for the acquisition of aberrant stemness and, concurrently, of refractoriness to differentiation. The metabostemness attribute can remove, diminish, or modify the nature of molecular barriers present in Waddington's epigenetic landscapes, thus allowing differentiated cells to more easily (re)-enter into CSC cellular macrostates. Activation of the metabostemness trait can poise cells with chromatin states competent for rapid dedifferentiation while concomitantly setting the idoneous metabolic stage for later reprograming stimuli to finish the journey from non-cancerous into tumor-initiating cells. Because only a few permitted metabotypes will be compatible with the operational properties owned by CSC cellular states, the metabostemness property provides a new framework through which to pharmacologically resolve the apparently impossible problem of discovering drugs aimed to target the molecular biology of the cancer stemness itself. The metabostemness cancer hallmark generates a shifting oncology theory that should guide a new era of metabolo-epigenetic cancer precision medicine.

Metabostemness: A New Cancer Hallmark

PubMed Central

Menendez, Javier A.; Alarcón, Tomás

2014-01-01

The acquisition of and departure from stemness in cancer tissues might not only be hardwired by genetic controllers, but also by the pivotal regulatory role of the cellular metabotype, which may act as a “starter dough” for cancer stemness traits. We have coined the term metabostemness to refer to the metabolic parameters causally controlling or functionally substituting the epitranscriptional orchestration of the genetic reprograming that redirects normal and tumor cells toward less-differentiated cancer stem cell (CSC) cellular states. Certain metabotypic alterations might operate as pivotal molecular events rendering a cell of origin susceptible to epigenetic rewiring required for the acquisition of aberrant stemness and, concurrently, of refractoriness to differentiation. The metabostemness attribute can remove, diminish, or modify the nature of molecular barriers present in Waddington’s epigenetic landscapes, thus allowing differentiated cells to more easily (re)-enter into CSC cellular macrostates. Activation of the metabostemness trait can poise cells with chromatin states competent for rapid dedifferentiation while concomitantly setting the idoneous metabolic stage for later reprograming stimuli to finish the journey from non-cancerous into tumor-initiating cells. Because only a few permitted metabotypes will be compatible with the operational properties owned by CSC cellular states, the metabostemness property provides a new framework through which to pharmacologically resolve the apparently impossible problem of discovering drugs aimed to target the molecular biology of the cancer stemness itself. The metabostemness cancer hallmark generates a shifting oncology theory that should guide a new era of metabolo-epigenetic cancer precision medicine. PMID:25325014

Truncated tyrosine kinase B brain-derived neurotrophic factor receptor directs cortical neural stem cells to a glial cell fate by a novel signaling mechanism.

PubMed

Cheng, Aiwu; Coksaygan, Turhan; Tang, Hongyan; Khatri, Rina; Balice-Gordon, Rita J; Rao, Mahendra S; Mattson, Mark P

2007-03-01

During development of the mammalian cerebral cortex neural stem cells (NSC) first generate neurons and subsequently produce glial cells. The mechanism(s) responsible for this developmental shift from neurogenesis to gliogenesis is unknown. Brain-derived neurotrophic factor (BDNF) is believed to play important roles in the development of the mammalian cerebral cortex; it enhances neurogenesis and promotes the differentiation and survival of newly generated neurons. Here, we provide evidence that a truncated form of the BDNF receptor tyrosine kinase B (trkB-t) plays a pivotal role in directing embryonic mouse cortical NSC to a glial cell fate. Expression of trkB-t promotes differentiation of NSC toward astrocytes while inhibiting neurogenesis both in cell culture and in vivo. The mechanism by which trkB-t induces astrocyte genesis is not simply the result of inhibition of full-length receptor with intrinsic tyrosine kinase activity signaling. Instead, binding of BDNF to trkB-t activates a signaling pathway (involving a G-protein and protein kinase C) that induced NSC to become glial progenitors and astrocytes. Thus, the increased expression of trkB-t in the embryonic cerebral cortex that occurs coincident with astrocyte production plays a pivotal role in the developmental transition from neurogenesis to gliogenesis. Our findings suggest a mechanism by which a single factor (BDNF) regulates the production of the two major cell types in the mammalian cerebral cortex.

Thrust Stand for Electric Propulsion Performance Evaluation

NASA Technical Reports Server (NTRS)

Polzin, Kurt A.; Markusic, Thomas E.; Stanojev, Boris J.; Dehoyos, Amado; Spaun, Benjamin

2006-01-01

An electric propulsion thrust stand capable of supporting testing of thrusters having a total mass of up to 125 kg and producing thrust levels between 100 microN to 1 N has been developed and tested. The design features a conventional hanging pendulum arm attached to a balance mechanism that converts horizontal deflections produced by the operating thruster into amplified vertical motion of a secondary arm. The level of amplification is changed through adjustment of the location of one of the pivot points linking the system. Response of the system depends on the relative magnitudes of the restoring moments applied by the displaced thruster mass and the twisting torsional pivots connecting the members of the balance mechanism. Displacement is measured using a non-contact, optical linear gap displacement transducer and balance oscillatory motion is attenuated using a passive, eddy-current damper. The thrust stand employs an automated leveling and thermal control system. Pools of liquid gallium are used to deliver power to the thruster without using solid wire connections, which can exert undesirable time-varying forces on the balance. These systems serve to eliminate sources of zero-drift that can occur as the stand thermally or mechanically shifts during the course of an experiment. An in-situ calibration rig allows for steady-state calibration before, during and after thruster operation. Thrust measurements were carried out on a cylindrical Hall thruster that produces mN-level thrust. The measurements were very repeatable, producing results that compare favorably with previously published performance data, but with considerably smaller uncertainty.

Improvement in thrust force estimation of solenoid valve considering minor hysteresis loop

NASA Astrophysics Data System (ADS)

Yoon, Myung-Hwan; Choi, Yun-Yong; Hong, Jung-Pyo

2017-05-01

Solenoid valve is a very important hydraulic actuator for an automatic transmission in terms of shift quality. The same form of pressure for the clutch and the input current are required for an ideal control. However, the gap between a pressure and a current can occur which brings a delay in a transmission and a decrease in quality. This problem is caused by hysteresis phenomenon. As the ascending or descending magnetic field is applied to the solenoid, different thrust forces are generated. This paper suggests the calculation method of the thrust force considering the hysteresis phenomenon and consequently the accurate force can be obtained. Such hysteresis occurs in ferromagnetic materials, however the hysteresis phenomenon includes a minor hysteresis loop which begins with an initial magnetization curve and is generated by DC biased field density. As the core of the solenoid is ferromagnetic material, an accurate thrust force is obtained by applying the minor hysteresis loop compared to the force calculated by considering only the initial magnetization curve. An analytical background and the detailed explanation of measuring the minor hysteresis loop are presented. Furthermore experimental results and finite element analysis results are compared for the verification.

Is Space Really Expanding? A Counterexample

NASA Astrophysics Data System (ADS)

Chodorowski, Michał J.

2007-03-01

In all Friedman models, the cosmological redshift is widely interpreted as a consequence of the general-relativistic phenomenon of expansion of space. Other commonly believed consequences of this phenomenon are superluminal recession velocities of distant galaxies, and the distance to the particle horizon greater than ct (where t is the age of the Universe), in apparent conflict with special relativity. Here, we study a particular Friedman model: empty universe. This model exhibits both cosmological redshift, superluminal velocities and infinite distance to the horizon. However, we show that the cosmological redshift is there simply a relativistic Doppler shift. Moreover, apparently superluminal velocities and ‘acausal’ distance to the horizon are in fact a direct consequence of special-relativistic phenomenon of time dilation, as well as of the adopted definition of distance in cosmology. There is no conflict with special relativity, whatsoever. In particular, inertial recession velocities are subluminal. Since in the real Universe, sufficiently distant galaxies recede with relativistic velocities, these special-relativistic effects must be at least partly responsible for the cosmological redshift and the aforementioned ‘superluminalities’, commonly attributed to the expansion of space. Let us finish with a question resembling a Buddhism-Zen ‘koan’: in an empty universe, what is expanding?

Analysis of Non-Pivotal Bioequivalence Studies Submitted in Abbreviated New Drug Submissions for Delayed-Release Drug Products.

PubMed

Kaur, Paramjeet; Jiang, Xiaojian; Stier, Ethan

2017-01-01

The US FDA's rule on "Requirements for Submission of Bioequivalence Data" requiring submission of all bioequivalence (BE) studies conducted on the same formulation of the drug product submitted for approval was published in Federal Register in January 2009. With the publication of this rule, we evaluated the impact of data from non-pivotal BE studies in assessing BE and identified the reasons for failed in vivo BE studies for generic oral delayed-release (DR) drug products only. We searched the Agency databases from January 2009 toDecember 2016 to identify Abbreviated New Drug Applications (ANDAs) submitted for DR drug products containing non-pivotal BE studies. Out of 202 ANDAs, 43 ANDAs contained 102 non-pivotal BE studies. Forty-nine non-pivotal BE studies were conducted on the to-be-marketed (TBM) formulation and 53 were conducted on formulations different from the TBM formulation. These experimental formulations primarily differed in the ratio of components of the enteric coating layer and/or amount (i.e., %w/w) of enteric coating layer. Of the 49 non-pivotal BE studies conducted on the TBM formulation, 41 failed to meet the BE acceptance criteria. The majority of failed non-pivotal BE studies on the TBM DR generic products had insufficient power, which was expected as these studies are exploratory in nature and not designed to have adequate power to pass the BE statistical criteria. In addition, among the failed non-pivotal BE studies on the TBM DR generic products, the most commonly failing pharmacokinetic parameter was Cmax. The data from these non-pivotal BE studies indicate that inadequate BE study design can lead to failure of the BE on the same formulation. Also, the non-pivotal BE studies on formulations different from the TBM formulation help us link the formulation design to the product performance in vivo. This article is open to POST-PUBLICATION REVIEW. Registered readers (see "For Readers") may comment by clicking on ABSTRACT on the issue's contents page.

Detection of an inhibitory cortical gradient underlying peak shift in learning: a neural basis for a false memory.

PubMed

Miasnikov, Alexandre A; Weinberger, Norman M

2012-11-01

Experience often does not produce veridical memory. Understanding false attribution of events constitutes an important problem in memory research. "Peak shift" is a well-characterized, controllable phenomenon in which human and animal subjects that receive reinforcement associated with one sensory stimulus later respond maximally to another stimulus in post-training stimulus generalization tests. Peak shift ordinarily develops in discrimination learning (reinforced CS+, unreinforced CS-) and has long been attributed to the interaction of an excitatory gradient centered on the CS+ and an inhibitory gradient centered on the CS-; the shift is away from the CS-. In contrast, we have obtained peak shifts during single tone frequency training, using stimulation of the cholinergic nucleus basalis (NB) to implant behavioral memory into the rat. As we also recorded cortical activity, we took the opportunity to investigate the possible existence of a neural frequency gradient that could account for behavioral peak shift. Behavioral frequency generalization gradients (FGGs, interruption of ongoing respiration) were determined twice before training while evoked potentials were recorded from the primary auditory cortex (A1), to obtain a baseline gradient of "habituatory" neural decrement. A post-training behavioral FGG obtained 24h after three daily sessions of a single tone paired with NB stimulation (200 trials/day) revealed a peak shift. The peak of the FGG was at a frequency lower than the CS while the cortical inhibitory gradient was at a frequency higher than the CS frequency. Further analysis indicated that the frequency location and magnitude of the gradient could account for the behavioral peak shift. These results provide a neural basis for a systematic case of memory misattribution and may provide an animal model for the study of the neural bases of a type of "false memory". Published by Elsevier Inc.

Phase Shifting Capacity of the Circadian Pacemaker Determined by the SCN Neuronal Network Organization

PubMed Central

vanderLeest, Henk Tjebbe; Rohling, Jos H. T.; Michel, Stephan; Meijer, Johanna H.

2009-01-01

Background In mammals, a major circadian pacemaker that drives daily rhythms is located in the suprachiasmatic nuclei (SCN), at the base of the hypothalamus. The SCN receive direct light input via the retino-hypothalamic tract. Light during the early night induces phase delays of circadian rhythms while during the late night it leads to phase advances. The effects of light on the circadian system are strongly dependent on the photoperiod to which animals are exposed. An explanation for this phenomenon is currently lacking. Methodology and Principal Findings We recorded running wheel activity in C57 mice and observed large amplitude phase shifts in short photoperiods and small shifts in long photoperiods. We investigated whether these different light responses under short and long days are expressed within the SCN by electrophysiological recordings of electrical impulse frequency in SCN slices. Application of N-methyl-D-aspartate (NMDA) induced sustained increments in electrical activity that were not significantly different in the slices from long and short photoperiods. These responses led to large phase shifts in slices from short days and small phase shifts in slices from long days. An analysis of neuronal subpopulation activity revealed that in short days the amplitude of the rhythm was larger than in long days. Conclusions The data indicate that the photoperiodic dependent phase responses are intrinsic to the SCN. In contrast to earlier predictions from limit cycle theory, we observed large phase shifting responses in high amplitude rhythms in slices from short days, and small shifts in low amplitude rhythms in slices from long days. We conclude that the photoperiodic dependent phase responses are determined by the SCN and propose that synchronization among SCN neurons enhances the phase shifting capacity of the circadian system. PMID:19305510

Design and evaluation of a single-pivot supported centrifugal blood pump.

PubMed

Yoshino, M; Uemura, M; Takahashi, K; Watanabe, N; Hoshi, H; Ohuchi, K; Nakamura, M; Fujita, H; Sakamoto, T; Takatani, S

2001-09-01

In order to develop a centrifugal blood pump that meets the requirements of a long-term, implantable circulatory support device, in this study a single-pivot bearing supported centrifugal blood pump was designed to evaluate its basic performance. The single-pivot structure consisted of a ceramic ball male pivot mounted on the bottom surface of the impeller and a polyethylene female pivot incorporated in the bottom pump casing. The follower magnet mounted inside the impeller was magnetically coupled to the driver magnet mounted on the shaft of the direct current brushless motor. As the motor rotated, the impeller rotated supported entirely by a single-pivot bearing system. The static pump performance obtained in the mock circulatory loop revealed an acceptable performance as a left ventricular assist device in terms of flow and head pressure. The pump flow of 5 L/min against the head pressure of 100 mm Hg was obtained at rotational speeds of 2,000 to 2,200 rpm. The maximum pump flow was 9 L/min with 2,200 rpm. The maximum electrical-to-hydraulic power conversion efficiency was around 14% at pump flows of 4 to 5 L/min. The stability of the impeller was demonstrated at the pump rpm higher than 1,400 with a single-pivot bearing without an additional support at its top. The single-pivot supported centrifugal pump can provide adequate flow and pressure as a ventricular assist device, but its mechanical stability and hemolytic as well as thrombotic performances must be tested prior to clinical use.

Exploring a recognition-induced recognition decrement

PubMed Central

Dopkins, Stephen; Ngo, Catherine Trinh; Sargent, Jesse

2007-01-01

Four experiments explored a recognition decrement that is associated with the recognition of a word from a short list. The stimulus material for demonstrating the phenomenon was a list of words of different syntactic types. A word from the list was recognized less well following a decision that a word of the same type had occurred in the list than following a decision that such a word had not occurred in the list. A recognition decrement did not occur for a word of a given type following a positive recognition decision to a word of a different type. A recognition decrement did not occur when the list consisted exclusively of nouns. It was concluded that the phenomenon may reflect a criterion shift but probably does not reflect a list strength effect, suppression, or familiarity attribution consequent to a perceived discrepancy between actual and expected fluency. PMID:17063915

High precision position sensor based on CPA in a composite multi-layered system.

PubMed

Dey, Sanjeeb; Singh, Suneel; Rao, Desai Narayana

2018-04-16

We propose a scheme for high precision position sensing based on coherent perfect absorption (CPA) in a five-layered structure comprising three layers of metal-dielectric composites and two spacer (air) layers. Both the outermost interfaces of the five layered medium are irradiated by two identical coherent light waves at the same angle of incidence. We first investigate the occurrence of CPA in a symmetric layered structure as a function of different system parameters for oblique incidence. Thereafter, by shifting the middle layer, beginning from one end of the structure to the other, we observe the periodic occurrence of extremely narrow CPA resonances at several positions of the middle layer. Moreover this phenomenon is seen to recur even at many other wavelengths. We discuss how the position sensitivity of this phenomenon can be utilized for designing a CPA based high precision position sensing device.

Bioinspired Thermoresponsive Photonic Polymers with Hierarchical Structures and Their Unique Properties.

PubMed

Lu, Tao; Zhu, Shenmin; Ma, Jun; Lin, Jinyou; Wang, Wanlin; Pan, Hui; Tian, Feng; Zhang, Wang; Zhang, Di

2015-10-01

Thermoresponsive photonic materials having hierarchical structures are created by combining a template of Morpho butterfly wings with poly(N-isopropylacrylamide) (PNIPAM) through a chemical bonding and polymerization route. These materials show temperature-induced color tunability. Through reacting with both NIPAM monomers and the amino groups of chitosan in wing scales, glutaraldehyde workes as a bridge by creating chemical bonding between the biotemplate and the PNIPAM. The corresponding reflection peaks red-shift with increase in temperature-an opposite phenomenon to previous studies, demonstrating a thermoresponsive photonic property. This unique phenomenon is caused by the refractive index change due to the volume change of PNIPAM during the temperature rising. This work sets up an efficient strategy for the fabrication of stimuli-responsive photonic materials with hierarchical structures toward extensive applications in science and technology. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Evolution of Ionospheric Convection during a Double Transpolar Arc Phenomenon on February 11, 1999

NASA Technical Reports Server (NTRS)

Narita, Y.; Maezawa, K.; Spann, J. F.; Parks, G. K.; Marklund, G. T.; Kullen, A.; Ivchenko, N.; Greenwald, R. A.; Sato, N.; Yamagishi, H.;

Understanding Rasch Measurement: Partial Credit Model and Pivot Anchoring.

ERIC Educational Resources Information Center

Bode, Rita K.

2001-01-01

Describes the Rasch measurement partial credit model, what it is, how it differs from other Rasch models, and when and how to use it. Also describes the calibration of instruments with increasingly complex items. Explains pivot anchoring and illustrates its use and describes the effect of pivot anchoring on step calibrations, item hierarchy, and…

HTS flywheel energy storage system with rotor shaft stabilized by feed-back control of armature currents of motor-generator

NASA Astrophysics Data System (ADS)

Tsukamoto, O.; Utsunomiya, A.

2007-10-01

We propose an HTS bulk bearing flywheel energy system (FWES) with rotor shaft stabilization system using feed-back control of the armature currents of the motor-generator. In the proposed system the rotor shift has a pivot bearing at one end of the shaft and an HTS bulk bearing (SMB) at the other end. The fluctuation of the rotor shaft with SMB is damped by feed-back control of the armature currents of the motor-generator sensing the position of the rotor shaft. The method has merits that the fluctuations are damped without active control magnet bearings and extra devices which may deteriorate the energy storage efficiency and need additional costs. The principle of the method was demonstrated by an experiment using a model permanent magnet motor.

'Fibre body': the concept of fibre in eighteenth-century medicine, c.1700-40.

PubMed

Ishizuka, Hisao

2012-10-01

This paper attempts a comprehensive account of 'fibre medicine' elaborated by iatromechanists from c. 1700 to c. 1740. Fibre medicine, a medical theory informed by the notion of the fibre, has been neglected by medical historians despite the pivotal role played by the fibre in animal economy. Referring to a wide range of medical fields such as anatomy, physiology, pathology, therapeutics and life sciences, this paper elucidates the ways that the fibre serves as an indispensable concept for iatromechanists to establish their medical theories. This paper also highlights the metaphorical dimension of the fibre as an integral part of fibre medicine. In re-evaluating the concept of the fibre, this paper seeks to redress the neuro-centric view of eighteenth-century medicine, and attempts to locate the fibre body amidst the fundamental shift from humoralism to solidism.

"That was grown folks' business": narrative reflection and response in older adults' family health history communication.

PubMed

Yamasaki, Jill; Hovick, Shelly R

2015-01-01

Given the importance of family health history and the pivotal role of older adults in communicating it, this study examines how African American older adults (a) characterize their understandings of health-related conditions in their family histories and (b) rationalize their motivations and constraints for sharing this information with current family members. Using narrative theory as a framework, we illustrate how the participants reflect on prior health-related experiences within the family to respond to moral and practical calls for communicating family health information to current relatives. Specifically, our analysis highlights how storied family secrets--as constructed by 28 participants in group and individual interviews--reveal and inform shifting cultural and generational practices that shape the lived health behaviors and communication of older adults at greater risk for health disparities.

Fas Versatile Signaling and Beyond: Pivotal Role of Tyrosine Phosphorylation in Context-Dependent Signaling and Diseases

PubMed Central

Chakrabandhu, Krittalak; Hueber, Anne-Odile

2016-01-01

The Fas/FasL system is known, first and foremost, as a potent apoptosis activator. While its proapoptotic features have been studied extensively, evidence that the Fas/FasL system can elicit non-death signals has also accumulated. These non-death signals can promote survival, proliferation, migration, and invasion of cells. The key molecular mechanism that determines the shift from cell death to non-death signals had remained unclear until the recent identification of the tyrosine phosphorylation in the death domain of Fas as the reversible signaling switch. In this review, we present the connection between the recent findings regarding the control of Fas multi-signals and the context-dependent signaling choices. This information can help explain variable roles of Fas signaling pathway in different pathologies. PMID:27799932

Disadvantages and advantages of transtibial technique for creating the anterior cruciate ligament femoral socket.

PubMed

Robin, Brett N; Lubowitz, James H

2014-10-01

Anterior cruciate ligament (ACL) femoral socket techniques have distinct advantages and disadvantages when considering the following techniques: transtibial, anteromedial portal, outside-in, and outside-in retroconstruction. There is no one perfect technique and we have an incomplete understanding of anatomical, biomechanical, isometry, stability, and clinical outcomes. Our primary focus is transtibial technique for creating the ACL femoral socket. Advantages include less invasive, isometric graft placement, stable Lachman exam, and minimal graft impingement with the tunnel and notch. Disadvantages include nonanatomic vertical graft placement that can cause rotational instability and positive pivot shift, interference screw divergence, graft-tunnel length mismatch, femoral socket constraint, posterior cruciate ligament impingement, and a short, oblique tibial tunnel that may undermine the medial plateau in an attempt to achieve anatomic ACL reconstruction. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Mesofluidic controlled robotic or prosthetic finger

DOEpatents

Lind, Randall F; Jansen, John F; Love, Lonnie J

2013-11-19

A mesofluidic powered robotic and/or prosthetic finger joint includes a first finger section having at least one mesofluidic actuator in fluid communication with a first actuator, a second mesofluidic actuator in fluid communication with a second actuator and a second prosthetic finger section pivotally connected to the first finger section by a joint pivot, wherein the first actuator pivotally cooperates with the second finger to provide a first mechanical advantage relative to the joint point and wherein the second actuator pivotally cooperates with the second finger section to provide a second mechanical advantage relative to the joint point.

Early and Late Shift of Brain Laterality in STG, HG, and Cerebellum with Normal Aging during a Short-Term Memory Task

PubMed Central

Abdul Manan, Hanani; Yusoff, Ahmad Nazlim; Franz, Elizabeth A.; Sarah Mukari, Siti Zamratol-Mai

2013-01-01

Evidence suggests that cognitive performance deteriorates in noisy backgrounds and the problems are more pronounced in older people due to brain deficits and changes. The present study used functional MRI (fMRI) to investigate the neural correlates of this phenomenon during short-term memory using a forward repeat task performed in quiet (STMQ) and in noise: 5-dB SNR (STMN) on four groups of participants of different ages. The performance of short-term memory tasks was measured behaviourally. No significant difference was found across age groups in STMQ. However, older adults (50–65 year olds) performed relatively poorly on the STMN. fMRI results on the laterality index indicate changes in hemispheric laterality in the superior temporal gyrus (STG), Heschl's gyrus (HG), and cerebellum, and a leftward asymmetry in younger participants which changes to a more rightward asymmetry in older participants. The results also indicate that the onset of the laterality shift varies from one brain region to another. STG and HG show a late shift while the cerebellum shows an earlier shift. The results also reveal that noise influences this shifting. Finally, the results support the hypothesis that functional networks that underlie STG, HG, and cerebellum undergo reorganization to compensate for the neural deficit/cognitive decline. PMID:23533806

16 CFR Figure 6 to Part 1633 - Burner Assembly Showing Arms and Pivots (Shoulder Screws), in Relation to, Portable Frame...

Code of Federal Regulations, 2010 CFR

2010-01-01

... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Burner Assembly Showing Arms and Pivots (Shoulder Screws), in Relation to, Portable Frame Allowing Burner Height Adjustment 6 Figure 6 to Part 1633... and Pivots (Shoulder Screws), in Relation to, Portable Frame Allowing Burner Height Adjustment...

16 CFR Figure 6 to Part 1633 - Burner Assembly Showing Arms and Pivots (Shoulder Screws), in Relation to, Portable Frame...

Code of Federal Regulations, 2013 CFR

2013-01-01

... 16 Commercial Practices 2 2013-01-01 2013-01-01 false Burner Assembly Showing Arms and Pivots (Shoulder Screws), in Relation to, Portable Frame Allowing Burner Height Adjustment 6 Figure 6 to Part 1633... and Pivots (Shoulder Screws), in Relation to, Portable Frame Allowing Burner Height Adjustment...

16 CFR Figure 6 to Part 1633 - Burner Assembly Showing Arms and Pivots (Shoulder Screws), in Relation to, Portable Frame...

Code of Federal Regulations, 2014 CFR

2014-01-01

... 16 Commercial Practices 2 2014-01-01 2014-01-01 false Burner Assembly Showing Arms and Pivots (Shoulder Screws), in Relation to, Portable Frame Allowing Burner Height Adjustment 6 Figure 6 to Part 1633... and Pivots (Shoulder Screws), in Relation to, Portable Frame Allowing Burner Height Adjustment...

Feasibility Study for a Dual Field of View-Single Detector Array Infrared System.

DTIC Science & Technology

1974-06-01

for 525 TV. Per Channelt C. DC. Ainlog& Dgitl Tretrs b~ td ~Secial multipleaed. Organ- 500 li1 cani be organized CAC nlg Dgia eprtr.Untdt 80 lioal...coupled transport phenomenon: charge coupled device (CCD) and bucket brigade device U ( BBD ). These devices are basically dynamic shift registers that...can be connected to form the serial in-serial uut memory. Both the CCD and BBD function by wanipulating char-e along a series of electrodes without

The response of a linear monostable system and its application in parameters estimation for PSK signals

NASA Astrophysics Data System (ADS)

Duan, Chaowei; Zhan, Yafeng

2016-03-01

The output characteristics of a linear monostable system driven with a periodic signal and an additive white Gaussian noise are studied in this paper. Theoretical analysis shows that the output signal-to-noise ratio (SNR) decreases monotonously with the increasing noise intensity but the output SNR-gain is stable. Inspired by this high SNR-gain phenomenon, this paper applies the linear monostable system in the parameters estimation algorithm for phase shift keying (PSK) signals and improves the estimation performance.

[Visit-to-visit blood pressure variability: clinical and prognostic significance].

PubMed

Kotovskaia, Iu V; Troitskaia, E A; Kobalava, Zh D

2014-01-01

The phenomenon of variability of blood pressure (BP) was studied for a long time, but recently it has received increased attention, with the focus shifted from short-term BP variability, estimated at daily monitoring for clinical blood pressure variability from visit to visit, which can be regarded as one of the indicators quality control of blood pressure with prolonged treatment. In light of the recent years of clinical data from visit to visit BP variability seems a promising new target for antihypertensive therapy.

Reason and Condition for Mode Kissing in MASW Method

NASA Astrophysics Data System (ADS)

Gao, Lingli; Xia, Jianghai; Pan, Yudi; Xu, Yixian

2016-05-01

Identifying correct modes of surface waves and picking accurate phase velocities are critical for obtaining an accurate S-wave velocity in MASW method. In most cases, inversion is easily conducted by picking the dispersion curves corresponding to different surface-wave modes individually. Neighboring surface-wave modes, however, will nearly meet (kiss) at some frequencies for some models. Around the frequencies, they have very close roots and energy peak shifts from one mode to another. At current dispersion image resolution, it is difficult to distinguish different modes when mode-kissing occurs, which is commonly seen in near-surface earth models. It will cause mode misidentification, and as a result, lead to a larger overestimation of S-wave velocity and error on depth. We newly defined two mode types based on the characteristics of the vertical eigendisplacements calculated by generalized reflection and transmission coefficient method. Rayleigh-wave mode near the kissing points (osculation points) change its type, that is to say, one Rayleigh-wave mode will contain different mode types. This mode type conversion will cause the mode-kissing phenomenon in dispersion images. Numerical tests indicate that the mode-kissing phenomenon is model dependent and that the existence of strong S-wave velocity contrasts increases the possibility of mode-kissing. The real-world data shows mode misidentification caused by mode-kissing phenomenon will result in higher S-wave velocity of bedrock. It reminds us to pay attention to this phenomenon when some of the underground information is known.

Design of the lac gene circuit revisited

PubMed Central

Savageau, Michael A.

2011-01-01

The lactose (lac) operon of Escherichia coli serves as the paradigm for gene regulation, not only for bacteria, but also for all biological systems from simple phage to humans. The details of the systems may differ, but the key conceptual framework remains, and the original system continues to reveal deeper insights with continued experimental and theoretical study. Nearly as long lasting in impact as the pivotal work of Jacob and Monod is the classic experiment of Novick and Weiner in which they demonstrated all-or-none gene expression in response to an artificial inducer. These results are often cited in claims that normal gene expression is in fact a discontinuous bistable phenomenon. In this paper, I review several levels of analysis of the lac system and introduce another perspective based on the construction of the system design space. These represent variations on a theme, based on a simply stated design principle, that captures the key qualitative features of the system in a largely mechanism-independent fashion. Moreover, this principle can be readily interpreted in terms of specific mechanisms to make predictions regarding monostable vs. bistable behavior. The regions of design space representing bifurcations are compared with the corresponding regions identified through bifurcation analysis. I present evidence based on biological considerations as well as modeling and analysis to suggest that induction of the lac system in its natural setting is a monostable continuously graded phenomenon. Nevertheless, it must be acknowledged that the lac stability question remains unsettled, and it undoubtedly will remain so until there are definitive experimental results. PMID:21414326

Concomitant tumor resistance: the role of tyrosine isomers in the mechanisms of metastases control.

PubMed

Ruggiero, Raúl A; Bruzzo, Juan; Chiarella, Paula; Bustuoabad, Oscar D; Meiss, Roberto P; Pasqualini, Christiane D

2012-03-01

Concomitant tumor resistance (CR) is a phenomenon in which a tumor-bearing host is resistant to the growth of secondary tumor implants and metastasis. Although previous studies indicated that T-cell-dependent processes mediate CR in hosts bearing immunogenic small tumors, manifestations of CR induced by immunogenic and nonimmunogenic large tumors have been associated with an elusive serum factor. In a recently published study, we identified this factor as meta-tyrosine and ortho-tyrosine, 2 isomers of tyrosine that would not be present in normal proteins. In 3 different murine models of cancer that generate CR, both meta- and ortho-tyrosine inhibited tumor growth. Additionally, we showed that both isoforms of tyrosine blocked metastasis in a fourth model that does not generate CR but is sensitive to CR induced by other tumors. Mechanistic studies showed that the antitumor effects of the tyrosine isomers were mediated in part by early inhibition of the MAP/ERK pathway and inactivation of STAT3, potentially driving tumor cells into a state of dormancy in G(0)-phase. Other mechanisms, putatively involving the activation of an intra-S-phase checkpoint, would also inhibit tumor proliferation by accumulating cells in S-phase. By revealing a molecular basis for the classical phenomenon of CR, our findings may stimulate new generalized approaches to limit the development of metastases that arise after resection of primary tumors or after other stressors that may promote the escape of metastases from dormancy, an issue that is of pivotal importance to oncologists and their patients.

APOBEC3G-Induced Hypermutation of Human Immunodeficiency Virus Type-1 Is Typically a Discrete “All or Nothing” Phenomenon

PubMed Central

Armitage, Andrew E.; Deforche, Koen; Chang, Chih-hao; Wee, Edmund; Kramer, Beatrice; Welch, John J.; Gerstoft, Jan; Fugger, Lars; McMichael, Andrew; Rambaut, Andrew; Iversen, Astrid K. N.

2012-01-01

The rapid evolution of Human Immunodeficiency Virus (HIV-1) allows studies of ongoing host–pathogen interactions. One key selective host factor is APOBEC3G (hA3G) that can cause extensive and inactivating Guanosine-to-Adenosine (G-to-A) mutation on HIV plus-strand DNA (termed hypermutation). HIV can inhibit this innate anti-viral defense through binding of the viral protein Vif to hA3G, but binding efficiency varies and hypermutation frequencies fluctuate in patients. A pivotal question is whether hA3G-induced G-to-A mutation is always lethal to the virus or if it may occur at sub-lethal frequencies that could increase viral diversification. We show in vitro that limiting-levels of hA3G-activity (i.e. when only a single hA3G-unit is likely to act on HIV) produce hypermutation frequencies similar to those in patients and demonstrate in silico that potentially non-lethal G-to-A mutation rates are ∼10-fold lower than the lowest observed hypermutation levels in vitro and in vivo. Our results suggest that even a single incorporated hA3G-unit is likely to cause extensive and inactivating levels of HIV hypermutation and that hypermutation therefore is typically a discrete “all or nothing” phenomenon. Thus, therapeutic measures that inhibit the interaction between Vif and hA3G will likely not increase virus diversification but expand the fraction of hypermutated proviruses within the infected host. PMID:22457633

Cervix-to-rectum measuring device in a radiation applicator for use in the treatment of cervical cancer

NASA Technical Reports Server (NTRS)

Fischell, D. R.; Mazique, J. C. (Inventor)

1981-01-01

A cervix-to-rectum measuring device to be used in the treatment of cervical cancer is described. It includes a handle and a probe pivotably connected to the handle for insertion in the rectum. The measuring device further includes means for coupling the handle to an intrauterine radiation applicator when the latter is positioned in the uterine cervix and the probe is inserted in the rectum to pivot the handle about the probe. A gear is provided which is adapted to pivot with the probe. A pinion pivotably connected to the handle meshes with the gear. A pointer fixed to the pinion is displaced in response to the pivoting of the handle about the probe, and this displacement can be read from a scale on the handle, providing an indication of the cervix-to-rectum distance.

Pivot tables for mortality analysis, or who needs life tables anyway?

PubMed

Wesley, David; Cox, Hugh F

2007-01-01

Actuarial life-table analysis has long been used by life insurance medical directors for mortality abstraction from clinical studies. Ironically, today's life actuary instead uses pivot tables to analyze mortality. Pivot tables (a feature/function in MS Excel) collapse various dimensions of data that were previously arranged in an "experience study" format. Summary statistics such as actual deaths, actual and expected mortality (usually measured in dollars), and calculated results such as actual to expected ratios, are then displayed in a 2-dimensional grid. The same analytic process, excluding the dollar focus, can be used for clinical mortality studies. For raw survival data, especially large datasets, this combination of experience study data and pivot tables has clear advantages over life-table analysis in both accuracy and flexibility. Using the SEER breast cancer data, we compare the results of life-table analysis and pivot-table analysis.

Microwave absorption properties of Ni/(C, silicides) nanocapsules

PubMed Central

2012-01-01

The microwave absorption properties of Ni/(C, silicides) nanocapsules prepared by an arc discharge method have been studied. The composition and the microstructure of the Ni/(C, silicides) nanocapsules were determined by means of X-ray diffraction, X-ray photoelectric spectroscopy, and transmission electron microscope observations. Silicides, in the forms of SiOx and SiC, mainly exist in the shells of the nanocapsules and result in a large amount of defects at the ‘core/shell’ interfaces as well as in the shells. The complex permittivity and microwave absorption properties of the Ni/(C, silicides) nanocapsules are improved by the doped silicides. Compared with those of Ni/C nanocapsules, the positions of maximum absorption peaks of the Ni/(C, silicides) nanocapsules exhibit large red shifts. An electric dipole model is proposed to explain this red shift phenomenon. PMID:22548846

Side-gate modulation effects on high-quality BN-Graphene-BN nanoribbon capacitors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Yang; Chen, Xiaolong; Ye, Weiguang

High-quality BN-Graphene-BN nanoribbon capacitors with double side-gates of graphene have been experimentally realized. The double side-gates can effectively modulate the electronic properties of graphene nanoribbon capacitors. By applying anti-symmetric side-gate voltages, we observed significant upward shifting and flattening of the V-shaped capacitance curve near the charge neutrality point. Symmetric side-gate voltages, however, only resulted in tilted upward shifting along the opposite direction of applied gate voltages. These modulation effects followed the behavior of graphene nanoribbons predicted theoretically for metallic side-gate modulation. The negative quantum capacitance phenomenon predicted by numerical simulations for graphene nanoribbons modulated by graphene side-gates was not observed,more » possibly due to the weakened interactions between the graphene nanoribbon and side-gate electrodes caused by the Ga{sup +} beam etching process.« less

Ion sensitivity of large-area epitaxial graphene film on SiC substrate

NASA Astrophysics Data System (ADS)

Mitsuno, Takanori; Taniguchi, Yoshiaki; Ohno, Yasuhide; Nagase, Masao

2017-11-01

We investigated the intrinsic ion sensitivity of graphene field-effect transistors (FETs) fabricated by a resist-free stencil mask lithography process from a large-scale graphene film epitaxially grown on a SiC substrate. A pH-adjusted phosphate-buffered solution was used for the measurement to eliminate the interference of other ions on the graphene FET's ion sensitivity. The charge neutrality point shifted negligibly with changing pH for the pH-adjusted phosphate-buffered solution, whereas for the mixed buffer solution, it shifted toward the negative gate voltage owing to the decrease in the concentration of phthalate ions. This phenomenon is contrary to that observed in previous reports. Overall, our results indicate that the graphene film is intrinsically insensitive to ions except for those with functional groups that interact with the graphene surface.

Reflection-refraction of attenuated waves at the interface between a thermo-poroelastic medium and a thermoelastic medium

NASA Astrophysics Data System (ADS)

Sharma, M. D.

2018-07-01

Phenomenon of reflection and refraction is considered at the plane interface between a thermoelastic medium and thermo-poroelastic medium. Both the media are isotropic and behave dissipative to wave propagation. Incident wave in thermo-poroelastic medium is considered inhomogeneous with deviation allowed between the directions of propagation and maximum attenuation. For this incidence, four attenuated waves reflect back in thermo-poroelastic medium and three waves refract to the continuing thermoelastic medium. Each of these reflected/refracted waves is inhomogeneous and propagates with a phase shift. The propagation characteristics (velocity, attenuation, inhomogeneity, phase shift, amplitude, energy) of reflected and refracted waves are calculated as functions of propagation direction and inhomogeneity of the incident wave. Variations in these propagation characteristics with the incident direction are illustrated through a numerical example.

Driving Method for Compensating Reliability Problem of Hydrogenated Amorphous Silicon Thin Film Transistors and Image Sticking Phenomenon in Active Matrix Organic Light-Emitting Diode Displays

NASA Astrophysics Data System (ADS)

Shin, Min-Seok; Jo, Yun-Rae; Kwon, Oh-Kyong

2011-03-01

In this paper, we propose a driving method for compensating the electrical instability of hydrogenated amorphous silicon (a-Si:H) thin film transistors (TFTs) and the luminance degradation of organic light-emitting diode (OLED) devices for large active matrix OLED (AMOLED) displays. The proposed driving method senses the electrical characteristics of a-Si:H TFTs and OLEDs using current integrators and compensates them by an external compensation method. Threshold voltage shift is controlled a using negative bias voltage. After applying the proposed driving method, the measured error of the maximum emission current ranges from -1.23 to +1.59 least significant bit (LSB) of a 10-bit gray scale under the threshold voltage shift ranging from -0.16 to 0.17 V.

Hard turning micro-machine tool

DOEpatents

DeVor, Richard E; Adair, Kurt; Kapoor, Shiv G

2013-10-22

A micro-scale apparatus for supporting a tool for hard turning comprises a base, a pivot coupled to the base, an actuator coupled to the base, and at least one member coupled to the actuator at one end and rotatably coupled to the pivot at another end. A tool mount is disposed on the at least one member. The at least one member defines a first lever arm between the pivot and the tool mount, and a second lever arm between the pivot and the actuator. The first lever arm has a length that is less than a length of the second lever arm. The actuator moves the tool mount along an arc.

PiVoT GPS Receiver

NASA Technical Reports Server (NTRS)

Wennersten, Miriam; Banes, Vince; Boegner, Greg; Clagnett, Charles; Dougherty, Lamar; Edwards, Bernard; Roman, Joe; Bauer, Frank H. (Technical Monitor)

2001-01-01

NASA Goddard Space Flight Center has built an open architecture, 24 channel spaceflight Global Positioning System (GPS) receiver. The compact PCI PiVoT GPS receiver card is based on the Mitel/GEC Plessey Builder 2 board. PiVoT uses two Plessey 2021 correlators to allow tracking of up to 24 separate GPS SV's on unique channels. Its four front ends can support four independent antennas, making it a useful card for hosting GPS attitude determination algorithms. It has been built using space quality, radiation tolerant parts. The PiVoT card works at a lower signal to noise ratio than the original Builder 2 board. It also hosts an improved clock oscillator. The PiVoT software is based on the original Piessey Builder 2 software ported to the Linux operating system. The software is posix compliant and can be easily converted to other posix operating systems. The software is open source to anyone with a licensing agreement with Plessey. Additional tasks can be added to the software to support GPS science experiments or attitude determination algorithms. The next generation PiVoT receiver will be a single radiation hardened compact PCI card containing the microprocessor and the GPS receiver optimized for use above the GPS constellation.

Continuous wavelength tunable laser source with optimum positioning of pivot axis for grating

DOEpatents

Pushkarsky, Michael; Amone, David F.

2010-06-08

A laser source (10) for generating a continuously wavelength tunable light (12) includes a gain media (16), an optical output coupler (36F), a cavity collimator (38A), a diffraction grating (30), a grating beam (54), and a beam attacher (56). The diffraction grating (30) is spaced apart from the cavity collimator (38A) and the grating (30) cooperates with the optical output coupler (36F) to define an external cavity (32). The grating (30) includes a grating face surface (42A) that is in a grating plane (42B). The beam attacher (56) retains the grating beam (54) and allows the grating beam (54) and the grating (30) to effectively pivot about a pivot axis (33) that is located approximately at an intersection of a pivot plane (50) and the grating plane (42B). As provided herein, the diffraction grating (30) can be pivoted about the unique pivot axis (33) to move the diffraction grating (30) relative to the gain media (16) to continuously tune the lasing frequency of the external cavity (32) and the wavelength of the output light (12) so that the output light (12) is mode hop free.

Gender differences in offaxis neuromuscular control during stepping under a slippery condition.

PubMed

Lee, Song Joo; Ren, Yupeng; Geiger, François; Zhang, Li-Qun

2013-11-01

Females are at greater risks of musculoskeletal injuries than are males, which may be related to decreased neuromuscular control in axial and/or frontal planes, offaxis neuromuscular control. The objective of this study was to investigate gender differences in offaxis neuromuscular control during stepping under a slippery condition. Forty-three healthy subjects (21 males and 22 females) performed different stepping tasks under a slippery condition, namely, free pivoting task (FPT) to control axial plane pivoting, free sliding task (FST) to control frontal plane sliding, and free pivoting and sliding task (FPST) to control axial pivoting, and frontal sliding on a custom-made offaxis elliptical trainer. Compared to males, females showed significantly higher pivoting instability, higher max internal and external pivoting angles, higher mean max medial and lateral sliding distance, and higher entropy of time to peak EMG in the medial and lateral gastrocnemius muscles during the FPST and higher entropy of time to peak EMG in the lateral gastrocnemius muscle during the FPT and FST. The findings may help us understand potential injury risk factors associated with gender differences, and provide a basis for developing targeted neuromuscular training to improve offaxis neuromuscular control, and reduce musculoskeletal injuries associated with excessive offaxis loadings.

Quiet-Sun Connection between the C IV Resonance Lines and the Photospheric Magnetic Field

NASA Astrophysics Data System (ADS)

Brynildsen, Nils; Kjeldseth-Moe, Olav; Maltby, Per

1996-05-01

The quiet-Sun relation between the C iv resonance line parameters and the photospheric magnetic field is studied with a spatial resolution of 1" x 1". The material is ordered into groups according to the magnitude of the magnetic flux density, |B|, and conditional probabilities are calculated. We find that red shifted profiles with either high intensity, large Doppler shift, or large line broadening occupy an increasing fraction of the area when |B| increases. These results are contrasted by blueshifted profiles which indicate a slight decrease with increasing magnetic flux density. The similarity in the results obtained with magneto grams taken several hours before and after the UV data led us to suggest that the tendency for red shifted profiles to outnumber blueshifted profiles in quiet regions originates in the super-granular network. Suggestions regarding the origin of the redshift phenomenon are briefly confronted with the observations. It appears difficult to explain the observations with models based on continuous gas flows. However, a model containing Alfvén wave pulses traveling from the corona toward the transition region promises to be compatible with the observations.

Stability study of solution-processed zinc tin oxide thin-film transistors

NASA Astrophysics Data System (ADS)

Zhang, Xue; Ndabakuranye, Jean Pierre; Kim, Dong Wook; Choi, Jong Sun; Park, Jaehoon

2015-11-01

In this study, the environmental dependence of the electrical stability of solution-processed n-channel zinc tin oxide (ZTO) thin-film transistors (TFTs) is reported. Under a prolonged negative gate bias stress, a negative shift in threshold voltage occurs in atmospheric air, whereas a negligible positive shift in threshold voltage occurs under vacuum. In the positive bias-stress experiments, a positive shift in threshold voltage was invariably observed both in atmospheric air and under vacuum. In this study, the negative gate-bias-stress-induced instability in atmospheric air is explained through an internal potential in the ZTO semiconductor, which can be generated owing to the interplay between H2O molecules and majority carrier electrons at the surface of the ZTO film. The positive bias-stress-induced instability is ascribed to electron-trapping phenomenon in and around the TFT channel region, which can be further augmented in the presence of air O2 molecules. These results suggest that the interaction between majority carriers and air molecules will have crucial implications for a reliable operation of solution-processed ZTO TFTs. [Figure not available: see fulltext.

Are fish outside their usual ranges early indicators of climate-driven range shifts?

PubMed

Fogarty, Hannah E; Burrows, Michael T; Pecl, Gretta T; Robinson, Lucy M; Poloczanska, Elvira S

2017-05-01

Shifts in species ranges are a global phenomenon, well known to occur in response to a changing climate. New species arriving in an area may become pest species, modify ecosystem structure, or represent challenges or opportunities for fisheries and recreation. Early detection of range shifts and prompt implementation of any appropriate management strategies is therefore crucial. This study investigates whether 'first sightings' of marine species outside their normal ranges could provide an early warning of impending climate-driven range shifts. We examine the relationships between first sightings and marine regions defined by patterns of local climate velocities (calculated on a 50-year timescale), while also considering the distribution of observational effort (i.e. number of sampling days recorded with biological observations in global databases). The marine trajectory regions include climate 'source' regions (areas lacking connections to warmer areas), 'corridor' regions (areas where moving isotherms converge), and 'sink' regions (areas where isotherms locally disappear). Additionally, we investigate the latitudinal band in which first sightings were recorded, and species' thermal affiliations. We found that first sightings are more likely to occur in climate sink and 'divergent' regions (areas where many rapid and diverging climate trajectories pass through) indicating a role of temperature in driving changes in marine species distributions. The majority of our fish first sightings appear to be tropical and subtropical species moving towards high latitudes, as would be expected in climate warming. Our results indicate that first sightings are likely related to longer-term climatic processes, and therefore have potential use to indicate likely climate-driven range shifts. The development of an approach to detect impending range shifts at an early stage will allow resource managers and researchers to better manage opportunities resulting from range-shifting species before they potentially colonize. © 2017 John Wiley & Sons Ltd.

Aggregation-induced emission spectral shift as a measure of local concentration of a pH-activatable rhodamine-based smart probe

NASA Astrophysics Data System (ADS)

Arsov, Zoran; Urbančič, Iztok; Štrancar, Janez

2018-02-01

Generating activatable probes that report about molecular vicinity through contact-based mechanisms such as aggregation can be very convenient. Specifically, such probes change a particular spectral property only at the intended biologically relevant target. Xanthene derivatives, for example rhodamines, are able to form aggregates. It is typical to examine aggregation by absorption spectroscopy but for microscopy applications utilizing fluorescent probes it is very important to perform characterization by measuring fluorescence spectra. First we show that excitation spectra of aqueous solutions of rhodamine 6G can be very informative about the aggregation features. Next we establish the dependence of the fluorescence emission spectral maximum shift on the dimer concentration. The obtained information helped us confirm the possibility of aggregation of a recently designed and synthesized rhodamine 6G-based pH-activatable fluorescent probe and to study its pH and concentration dependence. The size of the aggregation-induced emission spectral shift at specific position on the sample can be measured by fluorescence microspectroscopy, which at particular pH allows estimation of the local concentration of the observed probe at microscopic level. Therefore, we show that besides aggregation-caused quenching and aggregation-induced emission also aggregation-induced emission spectral shift can be a useful photophysical phenomenon.

New localized/delocalized emitting state of Eu 2+ in orange-emitting hexagonal EuAl 2O 4

DOE PAGES

Liu, Feng; Meltzer, Richard S.; Li, Xufan; ...

2014-11-18

Eu 2+-activated phosphors are being widely used in illuminations and displays. Some of these phosphors feature an extremely broad and red-shifted Eu 2+ emission band; however, convincing explanation of this phenomenon is lacking. Here we report a new localized/delocalized emitting state of Eu 2+ ions in a new hexagonal EuAl 2O 4 phosphor whose Eu 2+ luminescence exhibits a very large bandwidth and an extremely large Stokes shift. At 77 K, two luminescent sites responsible for 550 nm and 645 nm broadband emissions are recognized, while at room temperature only the 645 nm emission band emits. The 645 nm emissionmore » exhibits a typical radiative lifetime of 1.27 μs and an unusually large Stokes shift of 0.92 eV. We identify the 645 nm emission as originating from a new type of emitting state whose composition is predominantly that of localized 4f 65d character but which also contains a complementary component with delocalized conduction-band-like character. This investigation gives new insights into a unique type of Eu 2+ luminescence in solids whose emission exhibits both a very large bandwidth and an extremely large Stokes shift.« less

Evaluating trophic cascades as drivers of regime shifts in different ocean ecosystems

PubMed Central

Pershing, Andrew J.; Mills, Katherine E.; Record, Nicholas R.; Stamieszkin, Karen; Wurtzell, Katharine V.; Byron, Carrie J.; Fitzpatrick, Dominic; Golet, Walter J.; Koob, Elise

2015-01-01

In ecosystems that are strongly structured by predation, reducing top predator abundance can alter several lower trophic levels—a process known as a trophic cascade. A persistent trophic cascade also fits the definition of a regime shift. Such ‘trophic cascade regime shifts' have been reported in a few pelagic marine systems—notably the Black Sea, Baltic Sea and eastern Scotian Shelf—raising the question of how common this phenomenon is in the marine environment. We provide a general methodology for distinguishing top-down and bottom-up effects and apply this methodology to time series from these three ecosystems. We found evidence for top-down forcing in the Black Sea due primarily to gelatinous zooplankton. Changes in the Baltic Sea are primarily bottom-up, strongly structured by salinity, but top-down forcing related to changes in cod abundance also shapes the ecosystem. Changes in the eastern Scotian Shelf that were originally attributed to declines in groundfish are better explained by changes in stratification. Our review suggests that trophic cascade regime shifts are rare in open ocean ecosystems and that their likelihood increases as the residence time of water in the system increases. Our work challenges the assumption that negative correlation between consecutive trophic levels implies top-down forcing.

Response to climate change of montane herbaceous plants in the genus Rhodiola predicted by ecological niche modelling.

PubMed

You, Jianling; Qin, Xiaoping; Ranjitkar, Sailesh; Lougheed, Stephen C; Wang, Mingcheng; Zhou, Wen; Ouyang, Dongxin; Zhou, Yin; Xu, Jianchu; Zhang, Wenju; Wang, Yuguo; Yang, Ji; Song, Zhiping

2018-04-12

Climate change profoundly influences species distributions. These effects are evident in poleward latitudinal range shifts for many taxa, and upward altitudinal range shifts for alpine species, that resulted from increased annual global temperatures since the Last Glacial Maximum (LGM, ca. 22,000 BP). For the latter, the ultimate consequence of upward shifts may be extinction as species in the highest alpine ecosystems can migrate no further, a phenomenon often characterized as "nowhere to go". To predict responses to climate change of the alpine plants on the Qinghai-Tibetan Plateau (QTP), we used ecological niche modelling (ENM) to estimate the range shifts of 14 Rhodiola species, beginning with the Last Interglacial (ca. 120,000-140,000 BP) through to 2050. Distributions of Rhodiola species appear to be shaped by temperature-related variables. The southeastern QTP, and especially the Hengduan Mountains, were the origin and center of distribution for Rhodiola, and also served as refugia during the LGM. Under future climate scenario in 2050, Rhodiola species might have to migrate upward and northward, but many species would expand their ranges contra the prediction of the "nowhere to go" hypothesis, caused by the appearance of additional potential habitat concomitant with the reduction of permafrost with climate warming.

Medical Supplies Shortages and Burnout among Greek Health Care Workers during Economic Crisis: a Pilot Study

PubMed Central

Rachiotis, George; Kourousis, Christos; Kamilaraki, Maria; Symvoulakis, Emmanouil K.; Dounias, George; Hadjichristodoulou, Christos

2014-01-01

Greece has been seriously affected by the economic crisis. In 2011 there were reports of 40% reduction to public hospital budgets. Occasional shortages of medical supplies have been reported in mass media. We attempted to pivotally investigate the frequency of medical supplies shortages in two Greek hospital units of the National Health System and to also assess their possible impact on burnout risk of health care workers. We conducted a cross-sectional study (n=303) of health care workers in two Greek hospitals who were present at the workplace during a casually selected working day (morning shift work). The Maslach Burnout Inventory (MBI) was used as the measure of burnout. An additional questionnaire was used about demographics, and working conditions (duration of employment, cumulative night shifts, type of hospital including medical supplies shortages and their impact on quality of healthcare. The prevalence of emotional exhaustion, depersonalization and low personal accomplishment was 44.5%, 43.2% and 51.5%, respectively. Medical supply shortages were significantly associated with emotional exhaustion and depersonalization. This finding provides preliminary evidence that austerity has affected health care in Greece. Moreover, the medical supply shortages in Greek hospitals may reflect the unfolding humanitarian crisis of the country. PMID:24688306

Beyond mice and men: Environmental change, immunity and infections in wild ungulates

PubMed Central

Jolles, Anna E.; Beechler, Brianna R.; Dolan, Brian P.

2014-01-01

In the face of rapid environmental change, anticipating shifts in microparasite and macroparasite dynamics, including emergence events, is an enormous challenge. We argue that immunological studies in natural populations are pivotal to meeting this challenge: Many components of environmental change – shifts in biotic assemblages, altered climate patterns, and reduced environmental predictability – may affect host immunity. We suggest that wild ungulates can serve as model systems aiding the discovery of immunological mechanisms that link environmental change with parasite transmission dynamics. Our review of eco-immunological studies in wild ungulates reveals progress in understanding how co-infections affect immunity and parasite transmission; and how environmental and genetic factors interact to shape immunity. Changes in bioavailability of micronutrients have been linked to immunity and health in wild ungulates. Although physiological stress in response to environmental change has been assessed, downstream effects on immunity have not been studied. Moreover, the taxonomic range of ungulates studied is limited to bovids (bighorn sheep, Soay sheep, chamois, musk oxen, bison, African buffalo) and a few cervids (red deer, black-tailed deer). We discuss areas where future studies in ungulates could lead to significant contributions in understanding patterns of immunity and infection in natural populations and across species. PMID:25354672

Simulated East-west differences in F-region peak electron density at Far East mid-latitude region

NASA Astrophysics Data System (ADS)

Ren, Zhipeng; Zhao, Biqiang; Wan, Weixing; Liu, Libo

2017-04-01

In the present work, using Three-Dimensional Theoretical Ionospheric Model of the Earth in Institute of Geology and Geophysics, Chinese Academy of Sciences (TIME3D-IGGCAS), we simulated the east-west differences in Fregion peak electron density (NmF2) at Far East mid-latitude region.We found that, after removing the longitudinal variations of neutral parameters, TIME3D-IGGCAS can better represent the observed relative east-west difference (Rew) features. Rew is mainly negative (West NmF2 > East NmF2) at noon and positive (East NmF2 >West NmF2) at evening-night. The magnitude of daytime negative Rew is weak at local winter and strong at local summer, and the daytime Rew show two negative peaks around two equinoxes. With the increasing of solar flux level, the magnitude of Rew mainly become larger, and two daytime negative peaks slight shifts to June Solstice. With the decreasing of geographical latitude, Rew mainly become positive, and two daytime negative peaks slight shifts to June Solstice. Our simulation also suggested that the thermospheric zonal wind combined with the geomagnetic field configuration play a pivotal role in the formation of the ionospheric east-west differences at Far East midlatitude region.

Simulated East-west differences in F-region peak electron density at Far East mid-latitude region

NASA Astrophysics Data System (ADS)

Ren, Z.; Wan, W.

2017-12-01

In the present work, using Three-Dimensional Theoretical Ionospheric Model of the Earth in Institute of Geology and Geophysics, Chinese Academy of Sciences (TIME3D-IGGCAS), we simulated the east-west differences in Fregion peak electron density (NmF2) at Far East mid-latitude region.We found that, after removing the longitudinal variations of neutral parameters, TIME3D-IGGCAS can better represent the observed relative east-west difference (Rew) features. Rew is mainly negative (West NmF2 > East NmF2) at noon and positive (East NmF2 >West NmF2) at evening-night. The magnitude of daytime negative Rew is weak at local winter and strong at local summer, and the daytime Rew show two negative peaks around two equinoxes. With the increasing of solar flux level, the magnitude of Rew mainly become larger, and two daytime negative peaks slight shifts to June Solstice. With the decreasing of geographical latitude, Rew mainly become positive, and two daytime negative peaks slight shifts to June Solstice. Our simulation also suggested that the thermospheric zonal wind combined with the geomagnetic field configuration play a pivotal role in the formation of the ionospheric east-west differences at Far East midlatitude region.

Insights on the evolutionary origin of Detarioideae, a clade of ecologically dominant tropical African trees.

PubMed

de la Estrella, Manuel; Forest, Félix; Wieringa, Jan J; Fougère-Danezan, Marie; Bruneau, Anne

2017-06-01

African tropical forests are generally considered less diverse than their Neotropical and Asian counterparts. By contrast, the Detarioideae is much more diverse in Africa than in South America and Asia. To better understand the evolution of this contrasting diversity pattern, we investigated the biogeographical and ecological origin of this subfamily, testing whether they originated in dry biomes surrounding the Tethys Seaway as currently hypothesized for many groups of Leguminosae. We constructed the largest time-calibrated phylogeny for the subfamily to date, reconstructed ancestral states for geography and biome/habitat, estimated diversification and extinction rates, and evaluated biome/habitat and geographic shifts in Detarioideae. The ancestral habitat of Detarioideae is postulated to be a primary forest (terra firme) originated in Africa-South America, in the early Palaeocene, after which several biome/habitat and geographic shifts occurred. The origin of Detarioideae is older than previous estimates, which postulated a dry (succulent) biome origin according to the Tethys Seaway hypothesis, and instead we reveal a post Gondwana and terra firme origin for this early branching clade of legumes. Detarioideae include some of the most dominant trees in evergreen forests and have likely played a pivotal role in shaping continental African forest diversity. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

16 CFR Figure 6 to Part 1633 - Burner Assembly Showing Arms and Pivots (Shoulder Screws) in Relation to Portable Frame Allowing...

Code of Federal Regulations, 2011 CFR

2011-01-01

... 16 Commercial Practices 2 2011-01-01 2011-01-01 false Burner Assembly Showing Arms and Pivots (Shoulder Screws) in Relation to Portable Frame Allowing Burner Height Adjustment 6 Figure 6 to Part 1633... and Pivots (Shoulder Screws) in Relation to Portable Frame Allowing Burner Height Adjustment ER15MR06...

16 CFR Figure 6 to Part 1633 - Burner Assembly Showing Arms and Pivots (Shoulder Screws) in Relation to, Portable Frame Allowing...

Code of Federal Regulations, 2012 CFR

2012-01-01

... 16 Commercial Practices 2 2012-01-01 2012-01-01 false Burner Assembly Showing Arms and Pivots (Shoulder Screws) in Relation to, Portable Frame Allowing Burner Height Adjustment 6 Figure 6 to Part 1633... and Pivots (Shoulder Screws) in Relation to, Portable Frame Allowing Burner Height Adjustment ER15MR06...

Daily Fasting Blood Glucose Rhythm in Male Mice: A Role of the Circadian Clock in the Liver.

PubMed

Ando, Hitoshi; Ushijima, Kentaro; Shimba, Shigeki; Fujimura, Akio

2016-02-01

Fasting blood glucose (FBG) and hepatic glucose production are regulated according to a circadian rhythm. An early morning increase in FBG levels, which is pronounced among diabetic patients, is known as the dawn phenomenon. Although the intracellular circadian clock generates various molecular rhythms, whether the hepatic clock is involved in FBG rhythm remains unclear. To address this issue, we investigated the effects of phase shift and disruption of the hepatic clock on the FBG rhythm. In both C57BL/6J and diabetic ob/ob mice, FBG exhibited significant daily rhythms with a peak at the beginning of the dark phase. Light-phase restricted feeding altered the phase of FBG rhythm mildly in C57BL/6J mice and greatly in ob/ob mice, in concert with the phase shifts of mRNA expression rhythms of the clock and glucose production-related genes in the liver. Moreover, the rhythmicity of FBG and Glut2 expression was not detected in liver-specific Bmal1-deficient mice. Furthermore, treatment with octreotide suppressed the plasma growth hormone concentration but did not affect the hepatic mRNA expression of the clock genes or the rise in FBG during the latter half of the resting phase in C57BL/6J mice. These results suggest that the hepatic circadian clock plays a critical role in regulating the daily FBG rhythm, including the dawn phenomenon.

Micro electro mechanical system optical switching

DOEpatents

Thorson, Kevin J; Stevens, Rick C; Kryzak, Charles J; Leininger, Brian S; Kornrumpf, William P; Forman, Glenn A; Iannotti, Joseph A; Spahn, Olga B; Cowan, William D; Dagel, Daryl J

2013-12-17

The present disclosure includes apparatus, system, and method embodiments that provide micro electo mechanical system optical switching and methods of manufacturing switches. For example, one optical switch embodiment includes at least one micro electro mechanical system type pivot mirror structure disposed along a path of an optical signal, the structure having a mirror and an actuator, and the mirror having a pivot axis along a first edge and having a second edge rotatable with respect to the pivot axis, the mirror being capable of and arranged to be actuated to pivot betweeen a position parallel to a plane of an optical signal and a position substantially normal to the plane of the optical signal.

Tool for use in lifting pin supported objects

NASA Technical Reports Server (NTRS)

Marzek, R. A.; Read, W. S. (Inventor)

1974-01-01

A tool for use in lifting a pin-supported, electronic package mounted in juxtaposition with the surface of an electronic circuit board is described. The tool is configured to be received beneath a pin-supported package and is characterized by a manually operable linkage, including an elongated, rigid link is supported for axial reciprocation and a pivotal link pinned to the body and supported for oscillation induced in response to axial motion imparted to the rigid link. A lifting plate is pivotally coupled to the distal end of the pivotal link so that oscillatory motion imparted to the pivotal link serves to move the plate vertically for elevating the plate into lifting engagement with the electronic package positioned thereabove.

The Pivotal Role of Semantic Memory in Remembering the Past and Imagining the Future

PubMed Central

Irish, Muireann; Piguet, Olivier

2013-01-01

Episodic memory refers to a complex and multifaceted process which enables the retrieval of richly detailed evocative memories from the past. In contrast, semantic memory is conceptualized as the retrieval of general conceptual knowledge divested of a specific spatiotemporal context. The neural substrates of the episodic and semantic memory systems have been dissociated in healthy individuals during functional imaging studies, and in clinical cohorts, leading to the prevailing view that episodic and semantic memory represent functionally distinct systems subtended by discrete neurobiological substrates. Importantly, however, converging evidence focusing on widespread neural networks now points to significant overlap between those regions essential for retrieval of autobiographical memories, episodic learning, and semantic processing. Here we review recent advances in episodic memory research focusing on neurodegenerative populations which has proved revelatory for our understanding of the complex interplay between episodic and semantic memory. Whereas episodic memory research has traditionally focused on retrieval of autobiographical events from the past, we also include evidence from the recent paradigm shift in which episodic memory is viewed as an adaptive and constructive process which facilitates the imagining of possible events in the future. We examine the available evidence which converges to highlight the pivotal role of semantic memory in providing schemas and meaning whether one is engaged in autobiographical retrieval for the past, or indeed, is endeavoring to construct a plausible scenario of an event in the future. It therefore seems plausible to contend that semantic processing may underlie most, if not all, forms of episodic memory, irrespective of temporal condition. PMID:23565081

A serial qualitative interview study of infant feeding experiences: idealism meets realism

PubMed Central

Craig, Leone C A; Britten, Jane; McInnes, Rhona M

2012-01-01

Objective To investigate the infant feeding experiences of women and their significant others from pregnancy until 6 months after birth to establish what would make a difference. Design Qualitative serial interview study. Setting Two health boards in Scotland. Participants 72 of 541 invited pregnant women volunteered. 220 interviews approximately every 4 weeks with 36 women, 26 partners, eight maternal mothers, one sister and two health professionals took place. Results The overarching theme was a clash between overt or covert infant feeding idealism and the reality experienced. This is manifest as pivotal points where families perceive that the only solution that will restore family well-being is to stop breast feeding or introduce solids. Immediate family well-being is the overriding goal rather than theoretical longer term health benefits. Feeding education is perceived as unrealistic, overly technical and rules based which can undermine women's confidence. Unanimously families would prefer the balance to shift away from antenatal theory towards more help immediately after birth and at 3–4 months when solids are being considered. Family-orientated interactive discussions are valued above breastfeeding-centred checklist style encounters. Conclusions Adopting idealistic global policy goals like exclusive breast feeding until 6 months as individual goals for women is unhelpful. More achievable incremental goals are recommended. Using a proactive family-centred narrative approach to feeding care might enable pivotal points to be anticipated and resolved. More attention to the diverse values, meanings and emotions around infant feeding within families could help to reconcile health ideals with reality. PMID:22422915

Electrical servo actuator bracket. [fuel control valves on jet engines

NASA Technical Reports Server (NTRS)

Sawyer, R. V. (Inventor)

1981-01-01

An electrical servo actuator is mounted on a support arm which is allowed to pivot on a bolt through a fixed mounting bracket. The actuator is pivotally connected to the end of the support arm by a bolt which has an extension allowed to pass through a slot in the fixed mounting bracket. An actuator rod extends from the servo actuator to a crank arm which turns a control shaft. A short linear thrust of the rod pivots the crank arm through about 90 for full-on control with the rod contracted into the servo actuator, and full-off control when the rod is extended from the actuator. A spring moves the servo actuator and actuator rod toward the control crank arm once the actuator rod is fully extended in the full-off position. This assures the turning of the control shaft to a full-off position. A stop bolt and slot are provided to limit pivot motion. Once fully extended, the spring pivots the motion.

European Marketing Authorizations Granted Based on a Single Pivotal Clinical Trial: The Rule or the Exception?

PubMed

Morant, Anne Vinther; Vestergaard, Henrik Tang

2018-07-01

A minimum of two positive, adequate, and well-controlled clinical trials has historically been the gold standard for providing substantial evidence to support regulatory approval of a new medicine. Nevertheless, the present analysis of European Marketing Authorizations granted between 2012 and 2016 showed that 45% of new active substances were approved based on a single pivotal clinical trial. For therapeutic areas such as oncology and cardiovascular diseases, approvals based on a single pivotal trial are the rule rather than the exception, whereas new medicines within the nervous system area were generally supported by two or more pivotal trials. While overall similar trends have been observed in the US, the recent US Food and Drug Administration approvals of nervous system medicines based on a single pivotal trial suggest that a case-by-case scientific evaluation of the totality of evidence is increasingly applied to facilitate faster access of new medicines to patients suffering from serious diseases. © 2017 American Society for Clinical Pharmacology and Therapeutics.

PIVOT: platform for interactive analysis and visualization of transcriptomics data.

PubMed

Zhu, Qin; Fisher, Stephen A; Dueck, Hannah; Middleton, Sarah; Khaladkar, Mugdha; Kim, Junhyong

2018-01-05

Many R packages have been developed for transcriptome analysis but their use often requires familiarity with R and integrating results of different packages requires scripts to wrangle the datatypes. Furthermore, exploratory data analyses often generate multiple derived datasets such as data subsets or data transformations, which can be difficult to track. Here we present PIVOT, an R-based platform that wraps open source transcriptome analysis packages with a uniform user interface and graphical data management that allows non-programmers to interactively explore transcriptomics data. PIVOT supports more than 40 popular open source packages for transcriptome analysis and provides an extensive set of tools for statistical data manipulations. A graph-based visual interface is used to represent the links between derived datasets, allowing easy tracking of data versions. PIVOT further supports automatic report generation, publication-quality plots, and program/data state saving, such that all analysis can be saved, shared and reproduced. PIVOT will allow researchers with broad background to easily access sophisticated transcriptome analysis tools and interactively explore transcriptome datasets.

Flip-flops of FK Comae Berenices

NASA Astrophysics Data System (ADS)

Hackman, T.; Pelt, J.; Mantere, M. J.; Jetsu, L.; Korhonen, H.; Granzer, T.; Kajatkari, P.; Lehtinen, J.; Strassmeier, K. G.

2013-05-01

Context.FK Comae Berenices is a rapidly rotating magnetically active star, the light curve of which is modulated by cool spots on its surface. It was the first star where the "flip-flop" phenomenon was discovered. Since then, flip-flops in the spot activity have been reported in many other stars. Follow-up studies with increasing length have shown, however, that the phenomenon is more complex than was thought right after its discovery. Aims: Therefore, it is of interest to perform a more thorough study of the evolution of the spot activity in FK Com. In this study, we analyse 15 years of photometric observations with two different time series analysis methods, with a special emphasis on detecting flip-flop type events from the data. Methods: We apply the continuous period search and carrier fit methods on long-term standard Johnson-Cousins V-observations from the years 1995-2010. The observations were carried out with two automated photometric telescopes, Phoenix-10 and Amadeus T7 located in Arizona. Results: We identify complex phase behaviour in 6 of the 15 analysed data segments. We identify five flip-flop events and two cases of phase jumps, where the phase shift is Δφ < 0.4. In addition we see two mergers of spot regions and two cases where the apparent phase shifts are caused by spot regions drifting with respect to each other. Furthermore we detect variations in the rotation period corresponding to a differential rotation coefficient of |k| > 0.031. Conclusions: The flip-flop cannot be interpreted as a single phenomenon, where the main activity jumps from one active longitude to another. In some of our cases the phase shifts can be explained by differential rotation: two spot regions move with different angular velocity and even pass each other. Comparison between the methods show that the carrier fit utility is better in retrieving slow evolution especially from a low amplitude light curve, while the continuous period search is more sensitive in case of rapid changes. Based on data obtained with the Amadeus T7 Automatic Photoelectric Telescope (APT) at Fairborn Observatory, jointly operated by the University of Vienna and AIP, the Phoenix-10 APT at Mt. Hopkins, Arizona, and the Nordic Optical Telescope, Observatorio Roque de los Muchachos, La Palma, Canary Islands.The photometric observations are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/553/A40

Verification of the change blindness phenomenon while managing critical events on a combat information display.

PubMed

DiVita, Joseph; Obermayer, Richard; Nugent, William; Linville, James M

2004-01-01

Change blindness occurs when humans are unable to detect significant changes in objects and scenes after their attention is momentarily diverted. Because change blindness is relevant in many applied settings, the current study investigated the phenomenon in the context of tasks performed by naval command and control system personnel. Operators of such systems are often heavily loaded with concurrent visual search, situation assessment, voice communications, and control-display manipulation tasks at large, physically dispersed tactical situation displays. As the operators' attention shifts from one display to another, it creates an opportunity for changes to occur on unattended screens with potentially negative consequences. Our results show that on a display containing 8 objects of interest, considerable change blindness was demonstrated in that participants required 2 or more selections to correctly identify a changed object on nearly 1/3 of the test trials. Further, operator performance on 15% of the trials was equivalent to randomly guessing with replacement after making 3 incorrect selections. This research underscores the need for developing effective countermeasures to the change blindness phenomenon. Actual or potential uses of this research include interface design of computer workstations for military, nuclear power industry, air traffic control, crisis response center, and hospital emergency room applications.

Performance evaluation of FSO system using wavelength and time diversity over malaga turbulence channel with pointing errors

NASA Astrophysics Data System (ADS)

Balaji, K. A.; Prabu, K.

2018-03-01

There is an immense demand for high bandwidth and high data rate systems, which is fulfilled by wireless optical communication or free space optics (FSO). Hence FSO gained a pivotal role in research which has a added advantage of both cost-effective and licence free huge bandwidth. Unfortunately the optical signal in free space suffers from irradiance and phase fluctuations due to atmospheric turbulence and pointing errors which deteriorates the signal and degrades the performance of communication system over longer distance which is undesirable. In this paper, we have considered polarization shift keying (POLSK) system applied with wavelength and time diversity technique over Malaga(M)distribution to mitigate turbulence induced fading. We derived closed form mathematical expressions for estimating the systems outage probability and average bit error rate (BER). Ultimately from the results we can infer that wavelength and time diversity schemes enhances these systems performance.

The iliotibial band and anterolateral capsule have a combined attachment to the Segond fracture.

PubMed

Albers, Marcio; Shaikh, Humza; Herbst, Elmar; Onishi, Kentaro; Nagai, Kanto; Musahl, Volker; Fu, Freddie H

2018-05-01

The purpose of this report was to describe the injury mechanism, surgical findings, and outcomes in a 21-year-old professional female football player who presented with a complete anterior cruciate ligament (ACL) rupture and Segond fracture. Interview and video analysis were performed to elicit the injury mechanism. Clinical examination and imaging revealed a complete ACL tear, Segond fracture, lateral meniscus tear, MCL sprain, and posterolateral corner sprain. Examination under anaesthesia revealed Grade 2 pivot shift and varus/valgus instability. Surgical examination revealed attachment of the posterior fibres of the iliotibial band and the lateral capsule to the Segond fragment. The fracture was reduced with suture fixation, and an anatomic ACL reconstruction was performed. Follow-up demonstrated rotatory and anterior tibial translation stability, and imaging at 7 months post-operatively revealed no movement and continued osseous integration of the Segond fragment. Level of evidence V.

The elusive abnormal CO2 insertion enabled by metal-ligand cooperative photochemical selectivity inversion.

PubMed

Schneck, Felix; Ahrens, Jennifer; Finger, Markus; Stückl, A Claudia; Würtele, Christian; Schwarzer, Dirk; Schneider, Sven

2018-03-21

Direct hydrogenation of CO 2 to CO, the reverse water-gas shift reaction, is an attractive route to CO 2 utilization. However, the use of molecular catalysts is impeded by the general reactivity of metal hydrides with CO 2 . Insertion into M-H bonds results in formates (MO(O)CH), whereas the abnormal insertion to the hydroxycarbonyl isomer (MC(O)OH), which is the key intermediate for CO-selective catalysis, has never been directly observed. We here report that the selectivity of CO 2 insertion into a Ni-H bond can be inverted from normal to abnormal insertion upon switching from thermal to photochemical conditions. Mechanistic examination for abnormal insertion indicates photochemical N-H reductive elimination as the pivotal step that leads to an umpolung of the hydride ligand. This study conceptually introduces metal-ligand cooperation for selectivity control in photochemical transformations.

‘Fibre Body’: The Concept of Fibre in Eighteenth-century Medicine, c.1700–401

PubMed Central

Ishizuka, Hisao

2012-01-01

This paper attempts a comprehensive account of ‘fibre medicine’ elaborated by iatromechanists from c. 1700 to c. 1740. Fibre medicine, a medical theory informed by the notion of the fibre, has been neglected by medical historians despite the pivotal role played by the fibre in animal economy. Referring to a wide range of medical fields such as anatomy, physiology, pathology, therapeutics and life sciences, this paper elucidates the ways that the fibre serves as an indispensable concept for iatromechanists to establish their medical theories. This paper also highlights the metaphorical dimension of the fibre as an integral part of fibre medicine. In re-evaluating the concept of the fibre, this paper seeks to redress the neuro-centric view of eighteenth-century medicine, and attempts to locate the fibre body amidst the fundamental shift from humoralism to solidism. PMID:23112385

Ca2+-Dependent Regulations and Signaling in Skeletal Muscle: From Electro-Mechanical Coupling to Adaptation

PubMed Central

Gehlert, Sebastian; Bloch, Wilhelm; Suhr, Frank

2015-01-01

Calcium (Ca2+) plays a pivotal role in almost all cellular processes and ensures the functionality of an organism. In skeletal muscle fibers, Ca2+ is critically involved in the innervation of skeletal muscle fibers that results in the exertion of an action potential along the muscle fiber membrane, the prerequisite for skeletal muscle contraction. Furthermore and among others, Ca2+ regulates also intracellular processes, such as myosin-actin cross bridging, protein synthesis, protein degradation and fiber type shifting by the control of Ca2+-sensitive proteases and transcription factors, as well as mitochondrial adaptations, plasticity and respiration. These data highlight the overwhelming significance of Ca2+ ions for the integrity of skeletal muscle tissue. In this review, we address the major functions of Ca2+ ions in adult muscle but also highlight recent findings of critical Ca2+-dependent mechanisms essential for skeletal muscle-regulation and maintenance. PMID:25569087

Au and Pt nanoparticle supported catalysts tailored for H-2 production: From models to powder catalysts

DOE PAGES

T. D. Nguyen-Phan; Baber, A. E.; Rodriguez, J. A.; ...

2015-12-10

The use of metal nanoparticles (NPs), including Au and Pt, supported over oxides has been pivotal, and is ever increasing in enabling catalytic reactions which target the production of hydrogen. We review here the most recent works pertaining to the fundamental understanding of the structure, morphology, growth, characterization, and intrinsic phenomenological properties of Au– and Pt– based catalysts that influence the reactivity and selectivity to target hydrogen production. We draw on surface science and theoretical methods of model and powder catalysts using high resolution imaging, spectroscopy, scattering experiments, and theoretical studies. Based on these insights we identify key aspects ofmore » studies of supported metal nanoparticle (NP) catalysts for several reactions. The main focus of this review is on the intersection of catalytic chemistry related to the water-gas shift (WGS), oxygenate steam reforming (OSR), and solarassisted reactions (SAR).« less

Asymmetric Thrust Reversers

NASA Technical Reports Server (NTRS)

Chandler, Jesse M. (Inventor); Suciu, Gabriel L. (Inventor)

2018-01-01

An aircraft includes a propulsion supported within an aft portion of a fuselage A thrust reverser is mounted in the aft portion of the fuselage proximate the propulsion system for directing thrust in a direction to slow the aircraft. The thrust reverser includes an upper blocker door movable about a first pivot axis to a deployed position and a lower blocker door movable about a second pivot axis not parallel to the first pivot axis.

27. VIEW NORTHWEST FROM DECKING ON SOUTHEAST CORNER OF PIVOT ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

27. VIEW NORTHWEST FROM DECKING ON SOUTHEAST CORNER OF PIVOT PIER, DRIVE SYSTEM FOR SWING-SPAN INCLUDES: (from left to right) WEDGE DRIVE GEAR BOX, SHAFTS TO WEDGE DRIVE DRIVE, WEDGE DRIVE CRANK SHAFTS, ELECTRIC MOTOR, INTERNATIONAL HARVESTER GASOLINE ENGINE, CONTROL RODS FOR STARTING AND CHOKING ENGINE, PIVOT (bottom center), AND TRACK ON CONCRETE PIER - Tipers Bridge, Spanning Great Wicomico River at State Route 200, Kilmarnock, Lancaster County, VA

Calculation of laser induced impulse based on the laser supported detonation wave model with dissociation, ionization and radiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gan, Li, E-mail: ligan0001@gmail.com; Mousen, Cheng; Xiaokang, Li

In the laser intensity range that the laser supported detonation (LSD) wave can be maintained, dissociation, ionization and radiation take a substantial part of the incidence laser energy. There is little treatment on the phenomenon in the existing models, which brings obvious discrepancies between their predictions and the experiment results. Taking into account the impact of dissociation, ionization and radiation in the conservations of mass, momentum and energy, a modified LSD wave model is developed which fits the experimental data more effectively rather than the existing models. Taking into consideration the pressure decay of the normal and the radial rarefaction,more » the laser induced impulse that is delivered to the target surface is calculated in the air; and the dependencies of impulse performance on laser intensity, pulse width, ambient pressure and spot size are indicated. The results confirm that the dissociation is the pivotal factor of the appearance of the momentum coupling coefficient extremum. This study focuses on a more thorough understanding of LSD and the interaction between laser and matter.« less

New dietetic practitioners' perspectives on their education and training.

PubMed

Brady, Jennifer; Lordly, Daphne; MacLellan, Debbie; Gingras, Jacqui

2012-01-01

To elucidate the complex phenomenon of dietitian professional socialization, we examined factors that influence people's decisions to pursue a career in dietetics and how education and training processes influence the professional socialization of dietitians. Participants (n=12) had less than three years of work experience and included alumni from three Canadian universities representing different models of entry to practice. Three one-on-one interviews were conducted with each participant. The key influencing factor in participants' decision to pursue dietetics was the perceived congruence between dietetics and other aspects of their lives, including early interests and experiences (sports, food and cooking, an eating disorder), career aspirations (science, health care), and social networks (the desire to be a professional). A pivotal experience during high school or while enrolled in or after graduation from another program prompted participants' awareness of and subsequent decision to pursue a career in dietetics. Supportive relationships were vital to participants' professional socialization. Recruitment materials and education opportunities should help aspiring dietitians develop a clear idea of what being a dietitian means. Dietetic educators must attend to the informational and relational aspects involved in shaping future practitioners' dietitian identities.

Effect of Storage on Performance of Super Nickel-Cadmium Cells

NASA Technical Reports Server (NTRS)

Vaidyanathan, Hari; Rao, Gopalakrishna M.

1997-01-01

A study was undertaken to examine the capacity maintenance features of SUPER nickel-cadmium cells when stored for extended periods to determine whether the features change when the same kinds of positive plates as that used in nickel-hydrogen cells are used, The cells maintained their capacity when stored at 0 C in the discharged state and at 0 C in the charged state by continuously trickle charging. There was a capacity loss when stored in the open-circuit condition at 28 C. A cycling test at 17% depth of discharge for 2400 cycles using cells stored at various conditions showed that cells maintained good end of discharge voltage regardless of their storage history. However, the EOD voltages of stored cells were lower by 10 mV compared to those of fresh cells. The capacity at the end of the cycling test decreased for the stored cells by 2-7 Ah. The storage related capacity loss is lower for SUPER Ni-Cd cells compared to that of Ni-H2 cells containing a hydrogen precharge. The results suggest the pivotal role of hydrogen pressure in the capacity loss phenomenon.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Manna, P. K.; Skoropata, E.; Ting, Y-W

Exchange bias and interlayer exchange coupling are interface driven phenomena. Since an ideal interface is very challenging to achieve, a clear understanding of the chemical and magnetic natures of interfaces is pivotal to identify their influence on the magnetism. We have chosen Ni 80Fe 20/CoO(t CoO)/Co trilayers as a model system, and identified non-stoichiometric Ni-ferrite and Co-ferrite at the surface and interface, respectively. These ferrites, being ferrimagnets typically, should influence the exchange coupling. But, in our trilayers the interface ferrites were found not to be ferro-or ferri-magnetic; thus having no observable influence on the exchange coupling. Our analysis also revealedmore » that (i) interlayer exchange coupling was present between Ni 80Fe 20 and Co even though the interlayer thickness was significantly larger than expected for this phenomenon to happen, and (ii) the majority of the CoO layer (except some portion near the interface) did not contribute to the observed exchange bias. Here, we also identified that the interlayer exchange coupling and the exchange bias properties were not interdependent.« less

PHYSICS OF OUR DAYS: Nonlinear long waves on water and solitons

NASA Astrophysics Data System (ADS)

Zeytounian, R. Kh

1995-12-01

The water wave problem has been pivotal in the history of nonlinear wave theory. This problem is one of the most interesting and successful applications of nonlinear hydrodynamics. Waves on the free surface of a body of water (perfect liquid) have always been a fascinating subject, for they represent a familiar yet complex phenomenon, easy to observe but very difficult to describe! The archetypical model equations of Kordeweg and de Vries and of Boussinesq, for example, were originally derived as approximations for water waves, and research into the problem has been sustained vigorously up to the present day. In the present paper, the derivation of the model equations is given in depth and rational use is made of asymptotic methods. Indeed, it is important to understand that in some cases the derivation of these approximate equations is intuitive and heuristic. In fact, it is not clear how to insert the model equation under consideration into a hierarchy of rational approximations, which in turn result from the exact formulation of the selected water wave problem.

Enigma of drug-induced altered states of consciousness among the !Kung Bushmen of the Kalahari Desert.

PubMed

Dobkin De Rios, M

1986-03-01

This article examines data presented in Katz' book, Boiling Energy: Community Healing among the Kalahari Kung, particularly with regard to plant drugs present in the community during the 1968 visit. The author argues that the similarity of the Bushman trance state, kia and that of drug-induced altered states of consciousness has been paid too little attention in the research, and that an enigma currently exists with regard to the degree to which plant drugs may have influenced the !Kung trance phenomenon and healing beliefs. The author discusses the existing evidence for plant drug use based on Katz' research and the specimens currently on hand at the Harvard Botanical Museum herbarium, and presents a Table which contrasts drug-induced behaviors and ideologies of societies known or suspected to have used mind-altering drugs with similar behavior/beliefs of the !Kung. It is suggested that the influence of a number of psychoactive drugs may have played a much more pivotal role in Bushman behavior and belief than is generally acknowledged.

Interface mixing and its impact on exchange coupling in exchange biased systems

DOE PAGES

Manna, P. K.; Skoropata, E.; Ting, Y-W; ...

2016-10-05

Exchange bias and interlayer exchange coupling are interface driven phenomena. Since an ideal interface is very challenging to achieve, a clear understanding of the chemical and magnetic natures of interfaces is pivotal to identify their influence on the magnetism. We have chosen Ni 80Fe 20/CoO(t CoO)/Co trilayers as a model system, and identified non-stoichiometric Ni-ferrite and Co-ferrite at the surface and interface, respectively. These ferrites, being ferrimagnets typically, should influence the exchange coupling. But, in our trilayers the interface ferrites were found not to be ferro-or ferri-magnetic; thus having no observable influence on the exchange coupling. Our analysis also revealedmore » that (i) interlayer exchange coupling was present between Ni 80Fe 20 and Co even though the interlayer thickness was significantly larger than expected for this phenomenon to happen, and (ii) the majority of the CoO layer (except some portion near the interface) did not contribute to the observed exchange bias. Here, we also identified that the interlayer exchange coupling and the exchange bias properties were not interdependent.« less

Age-associated Cognitive Decline: Insights into Molecular Switches and Recovery Avenues.

PubMed

Konar, Arpita; Singh, Padmanabh; Thakur, Mahendra K

2016-03-01

Age-associated cognitive decline is an inevitable phenomenon that predisposes individuals for neurological and psychiatric disorders eventually affecting the quality of life. Scientists have endeavored to identify the key molecular switches that drive cognitive decline with advancing age. These newly identified molecules are then targeted as recovery of cognitive aging and related disorders. Cognitive decline during aging is multi-factorial and amongst several factors influencing this trajectory, gene expression changes are pivotal. Identifying these genes would elucidate the neurobiological underpinnings as well as offer clues that make certain individuals resilient to withstand the inevitable age-related deteriorations. Our laboratory has focused on this aspect and investigated a wide spectrum of genes involved in crucial brain functions that attribute to senescence induced cognitive deficits. We have recently identified master switches in the epigenome regulating gene expression alteration during brain aging. Interestingly, these factors when manipulated by chemical or genetic strategies successfully reverse the age-related cognitive impairments. In the present article, we review findings from our laboratory and others combined with supporting literary evidences on molecular switches of brain aging and their potential as recovery targets.

Stress optimization of leaf-spring crossed flexure pivots for an active Gurney flap mechanism

NASA Astrophysics Data System (ADS)

Freire Gómez, Jon; Booker, Julian D.; Mellor, Phil H.

2015-04-01

The EU's Green Rotorcraft programme is pursuing the development of a functional and airworthy Active Gurney Flap (AGF) for a full-scale helicopter rotor blade. Interest in the development of this `smart adaptive rotor blade' technology lies in its potential to provide a number of aerodynamic benefits, which would in turn translate into a reduction in fuel consumption and noise levels. The AGF mechanism selected employs leaf-spring crossed flexure pivots. These provide important advantages over bearings as they are not susceptible to seizing and do not require maintenance (i.e. lubrication or cleaning). A baseline design of this mechanism was successfully tested both in a fatigue rig and in a 2D wind tunnel environment at flight-representative deployment schedules. For full validation, a flight test would also be required. However, the severity of the in-flight loading conditions would likely compromise the mechanical integrity of the pivots' leaf-springs in their current form. This paper investigates the scope for stress reduction through three-dimensional shape optimization of the leaf-springs of a generic crossed flexure pivot. To this end, a procedure combining a linear strain energy formulation, a parametric leaf-spring profile definition and a series of optimization algorithms is employed. The resulting optimized leaf-springs are proven to be not only independent of the angular rotation at which the pivot operates, but also linearly scalable to leaf-springs of any length, minimum thickness and width. Validated using non-linear finite element analysis, the results show very significant stress reductions relative to pivots with constant cross section leaf-springs, of up to as much as 30% for the specific pivot configuration employed in the AGF mechanism. It is concluded that shape optimization offers great potential for reducing stress in crossed flexure pivots and, consequently, for extending their fatigue life and/or rotational range.

Further exploration of the conformational space of α-synuclein fibrils: solid-state NMR assignment of a high-pH polymorph.

PubMed

Verasdonck, Joeri; Bousset, Luc; Gath, Julia; Melki, Ronald; Böckmann, Anja; Meier, Beat H

2016-04-01

Polymorphism is a common and important phenomenon for protein fibrils which has been linked to the appearance of strains in prion and other neurodegenerative diseases. Parkinson disease is a frequently occurring neurodegenerative pathology, tightly associated with the formation of Lewy bodies. These deposits mainly consist of α-synuclein in fibrillar, β-sheet-rich form. α-synuclein is known to form numerous different polymorphs, which show distinct structural features. Here, we describe the chemical shift assignments, and derive the secondary structure, of a polymorph that was fibrillized at higher-than-physiological pH conditions. The fibrillar core contains residues 40-95, with both the C- and N-terminus not showing any ordered, rigid parts. The chemical shifts are similar to those recorded previously for an assigned polymorph that was fibrillized at neutral pH.

In vivo excitation of nanoparticles using luminescent bacteria

PubMed Central

Dragavon, Joe; Blazquez, Samantha; Rekiki, Abdessalem; Samson, Chelsea; Theodorou, Ioanna; Rogers, Kelly L.; Tournebize, Régis; Shorte, Spencer L.

2012-01-01

The lux operon derived from Photorhabdus luminescens incorporated into bacterial genomes, elicits the production of biological chemiluminescence typically centered on 490 nm. The light-producing bacteria are widely used for in vivo bioluminescence imaging. However, in living samples, a common difficulty is the presence of blue-green absorbers such as hemoglobin. Here we report a characterization of fluorescence by unbound excitation from luminescence, a phenomenon that exploits radiating luminescence to excite nearby fluorophores by epifluorescence. We show that photons from bioluminescent bacteria radiate over mesoscopic distances and induce a red-shifted fluorescent emission from appropriate fluorophores in a manner distinct from bioluminescence resonance energy transfer. Our results characterizing fluorescence by unbound excitation from luminescence, both in vitro and in vivo, demonstrate how the resulting blue-to-red wavelength shift is both necessary and sufficient to yield contrast enhancement revealing mesoscopic proximity of luminescent and fluorescent probes in the context of living biological tissues. PMID:22615349

Transcriptomic alterations during ageing reflect the shift from cancer to degenerative diseases in the elderly.

PubMed

Aramillo Irizar, Peer; Schäuble, Sascha; Esser, Daniela; Groth, Marco; Frahm, Christiane; Priebe, Steffen; Baumgart, Mario; Hartmann, Nils; Marthandan, Shiva; Menzel, Uwe; Müller, Julia; Schmidt, Silvio; Ast, Volker; Caliebe, Amke; König, Rainer; Krawczak, Michael; Ristow, Michael; Schuster, Stefan; Cellerino, Alessandro; Diekmann, Stephan; Englert, Christoph; Hemmerich, Peter; Sühnel, Jürgen; Guthke, Reinhard; Witte, Otto W; Platzer, Matthias; Ruppin, Eytan; Kaleta, Christoph

2018-01-30

Disease epidemiology during ageing shows a transition from cancer to degenerative chronic disorders as dominant contributors to mortality in the old. Nevertheless, it has remained unclear to what extent molecular signatures of ageing reflect this phenomenon. Here we report on the identification of a conserved transcriptomic signature of ageing based on gene expression data from four vertebrate species across four tissues. We find that ageing-associated transcriptomic changes follow trajectories similar to the transcriptional alterations observed in degenerative ageing diseases but are in opposite direction to the transcriptomic alterations observed in cancer. We confirm the existence of a similar antagonism on the genomic level, where a majority of shared risk alleles which increase the risk of cancer decrease the risk of chronic degenerative disorders and vice versa. These results reveal a fundamental trade-off between cancer and degenerative ageing diseases that sheds light on the pronounced shift in their epidemiology during ageing.

Visualizing the phenomena of wave interference, phase-shifting and polarization by interactive computer simulations

NASA Astrophysics Data System (ADS)

Rivera-Ortega, Uriel; Dirckx, Joris

2015-09-01

In this manuscript a computer based simulation is proposed for teaching concepts of interference of light (under the scheme of a Michelson interferometer), phase-shifting and polarization states. The user can change some parameters of the interfering waves, such as their amplitude and phase difference in order to graphically represent the polarization state of a simulated travelling wave. Regarding to the interference simulation, the user is able to change the wavelength and type of the interfering waves by selecting combinations between planar and Gaussian profiles, as well as the optical path difference by translating or tilting one of the two mirrors in the interferometer setup, all of this via a graphical user interface (GUI) designed in MATLAB. A theoretical introduction and simulation results for each phenomenon will be shown. Due to the simulation characteristics, this GUI can be a very good non-formal learning resource.

Effect of Cr doping on structural and magnetic properties of ZnS nanoparticles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Virpal,; Singh, Jasvir; Sharma, Sandeep

2016-05-23

The structural, optical and magnetic properties of pure and Cr doped ZnS nanoparticles were studied at room temperature. X-ray diffraction analysis confirmed the absence of any mixed phase and the cubic structure of ZnS in pure and Cr doped ZnS nanoparticles. Fourier transfer infrared spectra confirmed the Zn-S stretching bond at 664 cm{sup −1} of ZnS in all prepared nanoparticles. The UV-Visible absorption spectra showed blue shift which became even more pronounced in Cr doped ZnS nanoparticles. However, at relatively higher Cr concentrations a slower red shift was shown by the doped nanoparticles. This phenomenon is attributed to sp-d exchange interactionmore » that becomes prevalent at higher doping concentrations. Further, magnetic hysteresis measurements showed that Cr doped ZnS nanoparticles exhibited ferromagnetic behavior at room temperature.« less

A framework for the resilience of seagrass ecosystems.

PubMed

Unsworth, Richard K F; Collier, Catherine J; Waycott, Michelle; Mckenzie, Len J; Cullen-Unsworth, Leanne C

2015-11-15

Seagrass ecosystems represent a global marine resource that is declining across its range. To halt degradation and promote recovery over large scales, management requires a radical change in emphasis and application that seeks to enhance seagrass ecosystem resilience. In this review we examine how the resilience of seagrass ecosystems is becoming compromised by a range of local to global stressors, resulting in ecological regime shifts that undermine the long-term viability of these productive ecosystems. To examine regime shifts and the management actions that can influence this phenomenon we present a conceptual model of resilience in seagrass ecosystems. The model is founded on a series of features and modifiers that act as interacting influences upon seagrass ecosystem resilience. Improved understanding and appreciation of the factors and modifiers that govern resilience in seagrass ecosystems can be utilised to support much needed evidence based management of a vital natural resource. Copyright © 2015 Elsevier Ltd. All rights reserved.

Detection of shifted double JPEG compression by an adaptive DCT coefficient model

NASA Astrophysics Data System (ADS)

Wang, Shi-Lin; Liew, Alan Wee-Chung; Li, Sheng-Hong; Zhang, Yu-Jin; Li, Jian-Hua

2014-12-01

In many JPEG image splicing forgeries, the tampered image patch has been JPEG-compressed twice with different block alignments. Such phenomenon in JPEG image forgeries is called the shifted double JPEG (SDJPEG) compression effect. Detection of SDJPEG-compressed patches could help in detecting and locating the tampered region. However, the current SDJPEG detection methods do not provide satisfactory results especially when the tampered region is small. In this paper, we propose a new SDJPEG detection method based on an adaptive discrete cosine transform (DCT) coefficient model. DCT coefficient distributions for SDJPEG and non-SDJPEG patches have been analyzed and a discriminative feature has been proposed to perform the two-class classification. An adaptive approach is employed to select the most discriminative DCT modes for SDJPEG detection. The experimental results show that the proposed approach can achieve much better results compared with some existing approaches in SDJPEG patch detection especially when the patch size is small.

Surface potential on gold nanodisc arrays fabricated on silicon under light irradiation

NASA Astrophysics Data System (ADS)

Ezaki, Tomotarou; Matsutani, Akihiro; Nishioka, Kunio; Shoji, Dai; Sato, Mina; Okamoto, Takayuki; Isobe, Toshihiro; Nakajima, Akira; Matsushita, Sachiko

2018-06-01

This paper proposes Kelvin probe force microscopy (KFM) as a new measurement method of plasmon phenomenon. The surface potential of two arrays, namely, a monomeric array and a tetrameric array, of gold nanodiscs (600 nm diameter) on a silicon substrate fabricated by electron beam lithography was investigated by KFM with the view point of irradiation light wavelength change. In terms of the value of the surface potential, contrasting behaviour, a negative shift in the monomeric disc array and a positive shift in the tetrameric disc array, was observed by light irradiation. This interesting behaviour is thought to be related to a difference in localised plasmons caused by the disc arrangement and was investigated from various viewpoints, including Rayleigh anomalies. Finally, this paper reveals that KFM is powerful not only to investigate the plasmonic behaviour but also to predict the electron transportation.

Decoupled direct tracking control system based on use of a virtual track for multilayer disk with a separate guide layer

NASA Astrophysics Data System (ADS)

Tanaka, Yukinobu; Ogata, Takeshi; Imagawa, Seiji

2015-09-01

We developed a decoupled direct tracking control system for multilayer optical disk that uses a separate guide layer. Data marks are recorded on a recording layer immediately above the guide layer by using two spatially separated spots with different wavelengths. Accurate data mark recording requires that the relative positions of the corresponding spots on the recording layer and guide layer are maintained. However, a disk tilt can shift their relative positions and cause previously recorded data marks to be overwritten. Additionally, a two-input/two-output control system is susceptible to mutual interference phenomenon between the two outputs, which can destabilize tracking control. A tracking control system based on use of data marks previously recorded as a virtual track has been developed that prevents spot shifting and mutual interference even if the disk tilt reaches 0.7°, thereby preventing overwriting.

A climate-associated multispecies cryptic cline in the northwest Atlantic

PubMed Central

DiBacco, Claudio; Lowen, Ben; Beiko, Robert G.; Bentzen, Paul; Brickman, David; Johnson, Catherine; Wang, Zeliang; Wringe, Brendan F.; Bradbury, Ian R.

2018-01-01

The spatial genetic structure of most species in the open marine environment remains largely unresolved. This information gap creates uncertainty in the sustainable management, recovery, and associated resilience of marine communities and our capacity to extrapolate beyond the few species for which such information exists. We document a previously unidentified multispecies biogeographic break aligned with a steep climatic gradient and driven by seasonal temperature minima in the northwest Atlantic. The coherence of this genetic break across our five study species with contrasting life histories suggests a pervasive macroecological phenomenon. The integration of this genetic structure with habitat suitability models and climate forecasts predicts significant variation in northward distributional shifts among populations and availability of suitable habitat in future oceans. The results of our integrated approach provide new perspective on how cryptic intraspecific diversity associated with climatic variation influences species and community response to climate change beyond simple poleward shifts. PMID:29600272

Instance Analysis for the Error of Three-pivot Pressure Transducer Static Balancing Method for Hydraulic Turbine Runner

NASA Astrophysics Data System (ADS)

Weng, Hanli; Li, Youping

2017-04-01

The working principle, process device and test procedure of runner static balancing test method by weighting with three-pivot pressure transducers are introduced in this paper. Based on an actual instance of a V hydraulic turbine runner, the error and sensitivity of the three-pivot pressure transducer static balancing method are analysed. Suggestions about improving the accuracy and the application of the method are also proposed.

Simulator scene display evaluation device

NASA Technical Reports Server (NTRS)

Haines, R. F. (Inventor)

1986-01-01

An apparatus for aligning and calibrating scene displays in an aircraft simulator has a base on which all of the instruments for the aligning and calibrating are mounted. Laser directs beam at double right prism which is attached to pivoting support on base. The pivot point of the prism is located at the design eye point (DEP) of simulator during the aligning and calibrating. The objective lens in the base is movable on a track to follow the laser beam at different angles within the field of vision at the DEP. An eyepiece and a precision diopter are movable into a position behind the prism during the scene evaluation. A photometer or illuminometer is pivotable about the pivot into and out of position behind the eyepiece.

Laser beam alignment system

DOEpatents

Kasner, William H.; Racki, Daniel J.; Swenson, Clark E.

1984-01-01

A plurality of pivotal reflectors direct a high-power laser beam onto a workpiece, and a rotatable reflector is movable to a position wherein it intercepts the beam and deflects a major portion thereof away from its normal path, the remainder of the beam passing to the pivotal reflectors through an aperture in the rotating reflector. A plurality of targets are movable to positions intercepting the path of light traveling to the pivotal reflectors, and a preliminary adjustment of the latter is made by use of a low-power laser beam reflected from the rotating reflector, after which the same targets are used to make a final adjustment of the pivotal reflectors with the portion of the high-power laser beam passed through the rotating reflector.

The influence of bio-conjugation on photoluminescence of CdSe/ZnS quantum dots

NASA Astrophysics Data System (ADS)

Torchynska, Tetyana V.; Vorobiev, Yuri V.; Makhniy, Victor P.; Horley, Paul P.

2014-11-01

We report a considerable blue shift in the luminescence spectra of CdSe/ZnS quantum dots conjugated to anti-interleukin-10 antibodies. This phenomenon can be explained theoretically by accounting for bio-conjugation as a process causing electrostatic interaction between a quantum dot and an antibody, which reduces effective volume of the dot core. To solve the Schrödinger equation for an exciton confined in the quantum dot, we use mirror boundary conditions that were successfully tested for different geometries of quantum wells.

An alternating voltage battery with two salt-water oscillators

NASA Astrophysics Data System (ADS)

Cervellati, Rinaldo; Soldà, Roberto

2001-05-01

We built a simple alternating voltage battery that periodically reverses value and sign of its electromotive force (emf). This battery consists of two coupled concentration salt-water oscillators that are phase shifted by initially extracting some drops of salt solution from one of the two oscillators. Although the actual frequency (period: ˜30 s) and emf (˜±55 mV) is low, our battery is suitable to demonstrate a practical application of oscillating systems in the physical, chemical, or biological laboratory for undergraduates. Interpretation of the phenomenon is given.

Constructing a Scientific Explanation—A Narrative Account

NASA Astrophysics Data System (ADS)

Yeo, Jennifer; Gilbert, John K.

2014-07-01

Studies analyzing explanations that have been constructed by science students have found that they were generally weak and lack necessary features. The goal of this study was to establish the competencies that one needs to construct a scientific explanation. Scientific explanations can be looked at in three ways, in terms of their function, form and level, as being essentially sign-making processes. Taking a case study approach and using Lemke's multimodal framework, we analyzed the scientific explanation of an electromagnetic induction phenomenon constructed by one high school student. We found that such a construction involves the complex coordination of different types of signs, not only to represent the entities in the phenomenon, but also to support thinking and reasoning about it at abstract levels. Scientific conventions and rules, and everyday material and social tools were found to be crucial in shifting from one level of abstraction to another. The findings highlight the importance of developing the skillful use of schemes of scientific representation by students and familiarizing them with commonly encountered contexts.

Decentering and Related Constructs: A Critical Review and Metacognitive Processes Model

PubMed Central

Bernstein, Amit; Hadash, Yuval; Lichtash, Yael; Tanay, Galia; Shepherd, Kathrine; Fresco, David M.

2016-01-01

The capacity to shift experiential perspective—from within one’s subjective experience onto that experience—is fundamental to being human. Scholars have long theorized that this metacognitive capacity—which we refer to as decentering—may play an important role in mental health. To help illuminate this mental phenomenon and its links to mental health, we critically examine decentering-related constructs and their respective literatures (e.g., self-distanced perspective, cognitive distancing, cognitive defusion). First, we introduce a novel metacognitive processes model of decentering. Specifically, we propose that, to varying degrees, decentering-related constructs reflect a common mental phenomenon subserved by three interrelated metacognitive processes: meta-awareness, disidentification from internal experience, and reduced reactivity to thought content. Second, we examine extant research linking decentering-related constructs and their underlying metacognitive processes to mental health. We conclude by proposing future directions for research that transcends decentering-related constructs in an effort to advance the field’s understanding of this facet of human experience and its role in (mal)adaptation. PMID:26385999

Spectroscopic and theoretical investigations on intramolecular charge transfer phenomenon in 1-3-dioxolane derivative

NASA Astrophysics Data System (ADS)

Zhang, Zhiyong; Zhang, Zhongzhi; Luo, Yijing; Sun, Shanshan; Zhang, Guangqing

2018-02-01

High fluorescence quantum yield (FQY) and large Stokes shift (SS) cannot be easily achieved simultaneously by traditional PICT or TICT fluorescent probe. However, an 1-3-dioxolane derivative named 5-methyl-8,9-dihydro-5H-[1,3]dioxolo[4,5-b]carbazol-6(7H)-one (MDDCO) features both high FQY and large SS. The purpose of this study is to search the mechanism behind this phenomenon by theoretical method. Simulated structure changes and charge transfer suggest ICT process in MDDCO is similar to PLICT (Planarized Intramolecular Charge Transfer) process. Calculated UV-Vis spectra and fluorescence spectra show that PLICT-like state (S1 state) of MDDCO leads to large SS. Computed transient-absorption spectra and radiative decay rates indicate that PLICT-like state is key factor for high FQY of MDDCO. These findings suggest that PLICT-like state in 1,3-dioxolane derivatives can achieve both large SS and high FQY, which presents a new method for high-performance fluorescent probe design.

Energy Levels and Co-evolution of Product Innovation in Supply Chain Clusters

NASA Astrophysics Data System (ADS)

Ji, Guojun

In the last decade supply chain clusters phenomenon has emerged as a new approach in product innovation studies. This article makes three contributions to the approach by addressing some open issues. The first contribution is to explicitly incorporate the energy levels in the analysis. Hence, the unit of analysis is widened from sectoral systems of innovation to socio-technical systems. Hence, the unit of analysis is widened from sectoral systems of innovation to socio-technical systems. The second contribution is to suggest an analytical distinction between different evolution method, actors involved in them, and the institutions which guide actor's perceptions and activities. Thirdly, the article opens up the black box of institutions, making them an integral part of supply chain. The article provides a coherent conceptual multi-level perspective, using insights from sociology, institutional theory and innovation studies. The perspective is particularly useful to analyze long-term dynamics supply chain clusters phenomenon, shifts from one energy level to another and the co-evolution of product innovation.

Loss restlessness and gain calmness: durable effects of losses and gains on choice switching.

PubMed

Yechiam, Eldad; Zahavi, Gal; Arditi, Eli

2015-08-01

While the traditional conceptualization of the effect of losses focuses on bias in the subjective weight of losses compared with respective gains, some accounts suggest more global task-related effects of losses. Based on a recent attentional theory, we predicted a positive after-effect of losses on choice switching in later tasks. In two experimental studies, we found increased choice switching rates in tasks with losses compared to tasks with no losses. Additionally, this heightened shifting behavior was maintained in subsequent tasks that do not include losses, a phenomenon we refer to as "loss restlessness." Conversely, gains were found to have an opposite "calming" effect on choice switching. Surprisingly, the loss restlessness phenomenon was observed following an all-losses payoff regime but not after a task with symmetric mixed gains and losses. This suggests that the unresolved mental account following an all-losses regime increases search behavior. Potential implications to macro level phenomena, such as the leverage effect, are discussed.

Social status gates social attention in humans.

PubMed

Dalmaso, Mario; Pavan, Giulia; Castelli, Luigi; Galfano, Giovanni

2012-06-23

Humans tend to shift attention in response to the averted gaze of a face they are fixating, a phenomenon known as gaze cuing. In the present paper, we aimed to address whether the social status of the cuing face modulates this phenomenon. Participants were asked to look at the faces of 16 individuals and read fictive curriculum vitae associated with each of them that could describe the person as having a high or low social status. The association between each specific face and either high or low social status was counterbalanced between participants. The same faces were then used as stimuli in a gaze-cuing task. The results showed a greater gaze-cuing effect for high-status faces than for low-status faces, independently of the specific identity of the face. These findings confirm previous evidence regarding the important role of social factors in shaping social attention and show that a modulation of gaze cuing can be observed even when knowledge about social status is acquired through episodic learning.

[New information technologies and health consumerism].

PubMed

Vasconcellos-Silva, Paulo Roberto; Castiel, Luis David; Bagrichevsky, Marcos; Griep, Rosane Harter

2010-08-01

Concepts related to consumption have shifted to include social processes not previously covered by traditional categories. The current review analyzes the application of classical concepts of consumerism to practices recently identified in the health field, like the phenomenon of cyberchondria. The theoretical challenge relates to the difficulty in extrapolating from the economic perspectives of consumerism to self-care issues in the context of information and communication technologies (ICTs). Drawing on recent anthropological categories, the study seeks to understand the phenomenon of self-care commodification under the imperative of self-accountability for health. New consumer identities are described in light of the unprecedented issues concerning technical improvements currently altering the nature of self-care. The study concludes that health is consumed as vitality, broken down into commercial artifacts in the context of a new bioeconomy - no longer linked to the idea of emulation and possession, but to forms of self-perception and self-care in the face of multiple risks and new definitions of the human being.

A contradictory phenomenon of deshelving pulses in a dilute medium used for lengthened photon storage time.

PubMed

Ham, Byoung S

2010-08-16

Lengthening of photon storage time has been an important issue in quantum memories for long distance quantum communications utilizing quantum repeaters. Atom population transfer into an auxiliary spin state has been adapted to increase photon storage time of photon echoes. In this population transfer process phase shift to the collective atoms is inevitable, where the phase recovery condition must be multiple of 2pi to satisfy rephasing mechanism. Recent adaptation of the population transfer method to atomic frequency comb (AFC) echoes [Afzelius et al., Phys. Rev. Lett. 104, 040503 (2010)], where the population transfer method is originated in a controlled reversible inhomogeneous broadening technique [Moiseev and Kroll, Phys. Rev. Lett. 87, 173601 (2001)], however, shows contradictory phenomenon violating the phase recovery condition. This contradiction in AFC is reviewed as a general case of optical locking applied to a dilute medium for an optical depth-dependent coherence leakage resulting in partial retrieval efficiency.

Participation of the elderly, women, and minorities in pivotal trials supporting 2011-2013 U.S. Food and Drug Administration approvals.

PubMed

Downing, Nicholas S; Shah, Nilay D; Neiman, Joseph H; Aminawung, Jenerius A; Krumholz, Harlan M; Ross, Joseph S

2016-04-14

Pivotal trials, the clinical studies that inform U.S. Food and Drug Administration (FDA) approval decisions, provide the foundational evidence supporting the safety and efficacy of novel therapeutics. We determined the representation of the elderly, women, and patients from racial and ethnic minorities in pivotal trials and whether the FDA is making subgroup efficacy analyses among these subpopulations available to the public. We conducted a cross-sectional study of novel therapeutics approved by the FDA between 2011 and 2013. Using publicly available FDA documents, we collected information on the demographic characteristics of pivotal trial participants (age ≥65 years, sex [male, female], race [white, black, Asian, other], and ethnicity [Hispanic, non-Hispanic]) and determined the availability of subgroup analyses by age, sex, race, and ethnicity. We identified 86 novel therapeutic that were approved by the FDA between 2011 and 2013 for 92 indications on the basis of 206 pivotal trials. The median age of pivotal trial patients was 53.1 years (interquartile range 40.6-60.6), and the mean proportion of patients ≥65 years of age was 28.9 % (95 % CI 23.5-34.4 %). Similar proportions of pivotal trial participants were male (mean 50.3 %, 95 % CI 45.3-55.2 %) and female (mean 49.7 %, 95 % CI 44.7-54.7 %). Most participants were white (mean 79.2 %, 95 % CI 75.9-82.6 %), while the mean proportion of black patients was 7.4 % (95 % CI 5.5-9.3 %), that of Asian patients was 7.4 % (95 % CI 5.2-9.7 %), and that of patients of other races was 5.9 % (95 % CI 4.4-7.5 %). Information about ethnicity was available for only 59.8 % of indications, and where such data were available, the mean proportion of Hispanic participants was 13.3 % (95 % CI 10.3-16.3 %). FDA reviewers performed and made available subgroup efficacy analyses by age, sex, and race for at least one of the pivotal trials used as the basis of approval for over 80 % of indications. Although women are equally represented in pivotal trials supporting recent novel therapeutic approvals by the FDA, elderly patients and those from racial and ethnic minorities are underrepresented. FDA reviewers generally perform subgroup efficacy analyses by age, sex, and race and make these subgroup analyses available to the public.

All-Inside Single-Bundle Reconstruction of the Anterior Cruciate Ligament with the Anterior Half of the Peroneus Longus Tendon Compared to the Semitendinosus Tendon: A Two-Year Follow-Up Study.

PubMed

Bi, Mingguang; Zhao, Chen; Zhang, Shuijun; Yao, Bin; Hong, Zheping; Bi, Qing

2018-02-08

The anterior half of the peroneus longus tendon (AHPLT) has been reported to be acceptable for ligament reconstruction with respect to strength and safety. However, there is little information regarding the clinical outcomes after using the AHPLT compared with other autograft tendons. A prospective randomized controlled study was performed to compare the results of 62 cases of all-inside anatomical single-bundle anterior cruciate ligament (ACL) reconstruction using the AHPLT and 62 cases using semitendinosus graft with an average of 30.0 ± 3.6 months' follow-up. Tunnel placements of enrolled cases were measured on three-dimensional (3D) computed tomography (CT) and X-ray imaging. Knee stability was assessed using the anterior drawer test, pivot shift test, and KT-1000. The International Knee Documentation Committee (IKDC) 2000 subjective score was used to evaluate functional outcomes. The American Orthopedic Foot and Ankle Score (AOFAS) and the assessment of eversion muscle strength were performed to evaluate the function of the ankle donor site. Tunnel positions, which were confirmed with 3D CT, were in the anatomical positions. At the final follow-up, there were no significant differences between the semitendinosus group and the AHPLT group in the IKDC score (90.4 ± 7.1 vs. 89.3. ± 8.4), KT 1000 measurements (1.71 ± 0.57 vs. 1.85 ± 0.77), pivot shift test, and Visual Analogue Scale (VAS) (0.15 ± 0.36 vs. 0.10 ± 0.30). No obvious ankle site complications were found at 24 months. The average AOFAS score of the AHPLT group was comparable to that of the semitendinosus tendon group (99.1 ± 1.40 vs. 99.5 ± 1.21). There was no significant difference in clinical outcomes or knee stability between the semitendinosus group and the AHPLT group at the 2-year follow-up. An AHPLT autograft may be a good alternative for all-inside ACL reconstruction with respect to its strength, safety, and donor site morbidity. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Comparison of arthroscopic medial meniscal suture repair techniques: inside-out versus all-inside repair.

PubMed

Choi, Nam-Hong; Kim, Tae-Hyung; Victoroff, Brian N

2009-11-01

There are no reports comparing meniscal healing between inside-out and all-inside repairs using sutures. No difference in healing rate exists between meniscal repairs with inside-out and all-inside suture repair in conjunction with anterior cruciate ligament reconstruction with hamstring tendon. Cohort study; Level of evidence, 2. Forty-eight consecutive patients underwent meniscal repairs of longitudinal tears of the posterior horn of the medial meniscus combined with anterior cruciate ligament reconstructions. All-inside repair was attempted when the tears were located in the red-red zone or the ramp area of the meniscus. If a tear that was in the ramp area or red-red zone extended to the midbody of the meniscus, or if there was a tear in red-white zone, the inside-out repair technique was used. Fourteen patients had all-inside meniscal repairs, and 34 patients had inside-out meniscal repairs with absorbable sutures. Identical postoperative rehabilitation protocols were used. Postoperative evaluations included Lysholm knee scoring scale, Tegner activity levels, Lachman and pivot-shift tests, and KT-1000 arthrometer. Assessment of meniscal status was performed using joint line tenderness, McMurray test, and range of motion. Follow-up magnetic resonance imaging scans were obtained on all patients. Mean follow-up was 35.7 months. No patient had joint line tenderness or reported pain or clicking on McMurray test. There was no significant difference in range of motion between groups. Follow-up magnetic resonance imaging scans demonstrated that 10 (71.4%) menisci were healed and 4 (28.6%) partially healed in the all-inside group; 24 (70.6%) menisci were healed and 10 (29.4%) partially healed in the inside-out group. There was no significant difference in meniscal healing between groups. There were no differences in Lachman test, KT-1000 arthrometer side-to-side differences measurements, Lysholm scores, and Tegner activity scales. There was a significant difference in pivot-shift test between groups (P = .023). There were 2 complications associated with surgery. In the inside-out group, 1 patient required manipulation, and 2 patients had limited motion at final follow-up. Two patients in the inside-out group experienced transient saphenous nerve injury. There was no significant difference in meniscal healing between inside-out and all-inside repair techniques in combination with anterior cruciate ligament reconstructions.

The evaluation of muscle recovery after anatomical single-bundle ACL reconstruction using a quadriceps autograft.

PubMed

Iriuchishima, Takanori; Ryu, Keinosuke; Okano, Tatsumasa; Suruga, Makoto; Aizawa, Shin; Fu, Freddie H

2017-05-01

The purpose of this study was to reveal the degree of muscle recovery and report the clinical results of anatomical single-bundle ACL reconstruction using a quadriceps autograft. Twenty subjects undergoing anatomical single-bundle ACL reconstruction using a quadriceps autograft were included in this study. A 5-mm-wide, 8-cm-long graft, involving the entire layer of the quadriceps tendon, was harvested without bone block. The average graft diameter was 8.1 ± 1.4 mm. An initial tension of 30 N was applied. The femoral tunnel was created from the far-medial portal. Each femoral and tibial tunnel was created close to the antero-medial bundle insertion site. For the evaluation of muscle recovery (quadriceps and hamstring), a handheld dynamometer was used. The evaluation of muscle recovery was performed pre-operatively, and at 3, 6, 9, and 12 months after surgery. Muscle recovery data were calculated as a percentage of leg strength in the non-operated leg. Anterior tibial translation (ATT), pivot shift test, and IKDC score were evaluated. The average quadriceps strength pre-operatively, and at 3, 6, 9, and 12 months after ACL reconstruction was 90.5 ± 19, 67.8 ± 21.4, 84 ± 17.5, and 85.1 ± 12.6 %, respectively. The average hamstring strength pre-operatively, and at 3, 6, 9, and 12 months after ACL reconstruction was 99.5 ± 13.7, 78.7 ± 11.4, 90.5 ± 19, and 96.7 ± 13.8 %, respectively. ATT pre-operatively and at 12 months after surgery was 5.4 ± 1.3 and 1.0 ± 0.8 mm, respectively. No subjects exhibited positive pivot shift after surgery. Within 6 months following surgery, quadriceps hypotrophy was observed in all subjects. However, the hypotrophy had recovered at 12 months following surgery. No subjects complained of donor site pain after surgery. Anatomical single-bundle ACL reconstruction using a quadriceps autograft resulted in equivalent level of muscle recovery and knee stability when compared with previously reported ACL reconstruction using hamstrings tendon with no donor site complications. Case controlled study, Level III.

Re-use of pilot data and interim analysis of pivotal data in MRMC studies: a simulation study

NASA Astrophysics Data System (ADS)

Chen, Weijie; Samuelson, Frank; Sahiner, Berkman; Petrick, Nicholas

2017-03-01

Novel medical imaging devices are often evaluated with multi-reader multi-case (MRMC) studies in which radiologists read images of patient cases for a specified clinical task (e.g., cancer detection). A pilot study is often used to measure the effect size and variance parameters that are necessary for sizing a pivotal study (including sizing readers, non-diseased and diseased cases). Due to the practical difficulty of collecting patient cases or recruiting clinical readers, some investigators attempt to include the pilot data as part of their pivotal study. In other situations, some investigators attempt to perform an interim analysis of their pivotal study data based upon which the sample sizes may be re-estimated. Re-use of the pilot data or interim analyses of the pivotal data may inflate the type I error of the pivotal study. In this work, we use the Roe and Metz model to simulate MRMC data under the null hypothesis (i.e., two devices have equal diagnostic performance) and investigate the type I error rate for several practical designs involving re-use of pilot data or interim analysis of pivotal data. Our preliminary simulation results indicate that, under the simulation conditions we investigated, the inflation of type I error is none or only marginal for some design strategies (e.g., re-use of patient data without re-using readers, and size re-estimation without using the effect-size estimated in the interim analysis). Upon further verifications, these are potentially useful design methods in that they may help make a study less burdensome and have a better chance to succeed without substantial loss of the statistical rigor.

Origin and characteristics of high Shannon entropy at the pivot of locally stable rotors: insights from computational simulation.

PubMed

Ganesan, Anand N; Kuklik, Pawel; Gharaviri, Ali; Brooks, Anthony; Chapman, Darius; Lau, Dennis H; Roberts-Thomson, Kurt C; Sanders, Prashanthan

2014-01-01

Rotors are postulated to maintain cardiac fibrillation. Despite the importance of bipolar electrograms in clinical electrophysiology, few data exist on the properties of bipolar electrograms at rotor sites. The pivot of a spiral wave is characterized by relative uncertainty of wavefront propagation direction compared to the periphery. The bipolar electrograms used in electrophysiology recording encode information on both direction and timing of approaching wavefronts. To test the hypothesis that bipolar electrograms from the pivot of rotors have higher Shannon entropy (ShEn) than electrograms recorded at the periphery due to the spatial dynamics of spiral waves. We studied spiral wave propagation in 2-dimensional sheets constructed using a simple cell automaton (FitzHugh-Nagumo), atrial (Courtemanche-Ramirez-Nattel) and ventricular (Luo-Rudy) myocyte cell models and in a geometric model spiral wave. In each system, bipolar electrogram recordings were simulated, and Shannon entropy maps constructed as a measure of electrogram information content. ShEn was consistently highest in the pivoting region associated with the phase singularity of the spiral wave. This property was consistently preserved across; (i) variation of model system (ii) alterations in bipolar electrode spacing, (iii) alternative bipolar electrode orientation (iv) bipolar electrogram filtering and (v) in the presence of rotor meander. Directional activation plots demonstrated that the origin of high ShEn at the pivot was the directional diversity of wavefront propagation observed in this location. The pivot of the rotor is consistently associated with high Shannon entropy of bipolar electrograms despite differences in action potential model, bipolar electrode spacing, signal filtering and rotor meander. Maximum ShEn is co-located with the pivot for rotors observed in the bipolar electrogram recording mode, and may be an intrinsic property of spiral wave dynamic behaviour.

Focus collimator press for a collimator for gamma ray cameras

DOE Office of Scientific and Technical Information (OSTI.GOV)

York, R.N.; York, D.L.

A focus collimator press for collimators for gamma ray cameras is described comprising a pivot arm of fixed length mounted on a travelling pivot which is movable in the plane of a spaced apart work table surface in a direction toward and away from the work table. A press plate is carried at the opposite end of the fixed length pivot arm, and is maintained in registration with the same portion of the work table for pressing engagement with each undulating radiation opaque strip as it is added to the top of a collimator stack in process by movement ofmore » the travelling pivot inward toward the work table. This enables the press plate to maintain its relative position above the collimator stack and at the same time the angle of the press plate changes, becoming less acute in relation to the work table as the travelling pivot motes inwardly toward the work table. The fixed length of the pivot arm is substantially equal to the focal point of the converging apertures formed by each pair of undulating strips stacked together. Thus, the focal point of each aperture row falls substantially on the axis of the travelling pivot, and since it moves in the plane of the work table surface the focal point of each aperture row is directed to lie in the same common plane. When one of two collimator stacks made in this way is rotated 180 degrees and the two bonded together along their respective first strips, all focal points of every aperture row lie on the central axis of the completed collimator.« less

Novel and successful free comments method for sensory characterization of chocolate ice cream: A comparative study between pivot profile and comment analysis.

PubMed

Fonseca, Fernando G A; Esmerino, Erick A; Filho, Elson R Tavares; Ferraz, Juliana P; da Cruz, Adriano G; Bolini, Helena M A

2016-05-01

Rapid sensory profiling methods have gained space in the sensory evaluation field. Techniques using direct analysis of the terms generated by consumers are considered easy to perform, without specific training requirements, thus improving knowledge about consumer perceptions on various products. This study aimed to determine the sensory profile of different commercial samples of chocolate ice cream, labeled as conventional and light or diet, using the "comment analysis" and "pivot profile" methods, based on consumers' perceptions. In the comment analysis task, consumers responded to 2 separate open questions describing the sensory attributes they liked or disliked in each sample. In the pivot profile method, samples were served in pairs (consisting of a coded sample and pivot), and consumers indicated the higher and lower intensity attributes in the target sample compared with the pivot. We observed that both methods were able to characterize the different chocolate ice cream samples using consumer perception, with high correlation results and configurational similarity (regression vector coefficient=0.917) between them. However, it is worth emphasizing that comment analysis is performed intuitively by consumers, whereas the pivot profile method showed high analytical and discriminative power even using consumers, proving to be a promising technique for routine application when classical descriptive methods cannot be used. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Osteopontin plays a pivotal role in increasing severity of respiratory syncytial virus infection

PubMed Central

Sampayo-Escobar, Viviana; Green, Ryan; Cheung, Michael B.; Bedi, Raminder; Mohapatra, Subhra

2018-01-01

The molecular mechanisms underlying susceptibility to severe respiratory syncytial virus (RSV) infection remain poorly understood. Herein, we report on the role of osteopontin (OPN) in regulation of RSV infection in human epithelial cells and how interleukin-1 beta (IL-1β), a cytokine secreted soon after RSV infection, when persistently expressed can induce OPN expression leading to increased viral infection. We first compared OPN expression in two human epithelial cell lines: HEK-293 and HEp-2. In contrast to HEp-2, HEK-293 expresses low levels of pro-caspase-1 resulting in decreased IL-1β expression in response to RSV infection. We found a correlation between low IL-1β levels and a delay in induction of OPN expression in RSV-infected HEK-293 cells compared to HEp-2. This phenomenon could partially explain the high susceptibility of HEp-2 cells to RSV infection versus the moderate susceptibility of HEK-293 cells. Also, HEK-293 cells expressing low levels of pro-caspase-1 exhibit decreased IL-1β expression and delayed OPN expression in response to RSV infection. HEK-293 cells incubated with human rIL-1β showed a dose-dependent increase in OPN expression upon RSV infection. Also, incubation with rOPN increased RSV viral load. Moreover, HEp-2 cells or mice infected with a mucogenic RSV strain RSV-L19F showed elevated levels of OPN in contrast to mice infected with the laboratory RSV strain rA2. This correlated with elevated levels of OPN following infection with RSV-L19F compared to rA2. Together, these results demonstrate that increased OPN expression is regulated in part by IL-1β, and the interplay between IL-1β and OPN signaling may play a pivotal role in the spread of RSV infection. PMID:29677209

Autologous plasma and its supporting role in fat graft survival: A relevant vector to counteract resorption in lipofilling.

PubMed

Stillaert, Filip; Depypere, Bernard; Doornaert, Maarten; Creytens, David; De Clercq, Heidi; Cornelissen, Ria; Monstrey, Stan; Blondeel, Phillip

2016-07-01

Fat grafting has become a widespread technique for different reconstructive and esthetic purposes. However, the disadvantage of fat grafting is the unpredictable resorption rate that often necessitates repetitive procedures, which in turn may have an impact on the morbidity. During the immediate, post-graft, ischemic period, cells survive due to the process of plasmatic imbibition. This biological phenomenon precedes the ingrowth of neo-capillaries that eventually nourish the graft and help establish a long-term homeostatic equilibrium. Both partners, the graft and the recipient bed, contribute to the revascularization process. Hypothetically, enrichment of the recipient site with autologous plasma could have a beneficial role to enhance fat graft survival. We investigated whether plasma supported the viability of the lipoaspirate (LA) material. Plasma was isolated from blood samples collected from eight patients during the elective lipofilling procedures. An in vitro study assessed the viability of LA cells using plasma as a culture medium compared to the traditional culture media. In vitro analysis confirmed sustained viability of LA cells compared to the standard media and control media during 7 consecutive days. The behavior of the fat grafts in plasma showed similarities with those incubated in the traditional culture media. In future, these findings could be translated to a clinical setting. Plasma is the only autologous substrate available in large quantities in the human body. The addition of the supporting agents, such as plasma, could contribute to a better graft survival with more stable clinical outcomes in the long term. The rationale behind the technique is based on the phenomenon of plasmatic imbibition and the reasoning that the extracellular matrix plays a pivotal role in cellular survival. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

The Portrayal of Industrial Melanism in American College General Biology Textbooks

NASA Astrophysics Data System (ADS)

Fulford, Janice Marie; Rudge, David Wÿss

2016-08-01

The phenomenon of industrial melanism (IM) became widely acknowledged as a well-documented example of natural selection largely as a result of H.B.D. Kettlewell's pioneering research on the subject in the early 1950s. It was quickly picked up by American biology textbooks starting in the early 1960s and became ubiquitous throughout the 1970s, 1980s and 1990s. While recent research on the phenomenon broadly supports Kettlewell's explanation of IM in the peppered moth, which in turn has strengthened this example of natural selection, textbook IM entries have actually declined in recent years in favor of other examples. In a previous paper, we drew attention to the pivotal role visual aspects played in the introduction of IM into (and its subsequent removal from) textbook accounts. The present article continues this investigation by analyzing textual passages on industrial melanism within a stratified random sample of textbooks from the 1960s to the 2000s. The fact that this example of natural selection was included by multiple publishers independently, in a short period of time, makes it uniquely qualified for a textbook study of this kind. The purpose of the present project was to determine whether these textbooks contain what has come to be known as the standard peppered moth story. Three complete series were also inspected for change across time. Our analysis focused on (1) the amount of text devoted to industrial melanism; (2) what specific science content elements were present; and (3) what, if any, nature of science (NOS) aspects were included. The study documents an increase in the amount of text devoted to industrial melanism over the decades. In spite of this increase, only modest changes in science content and NOS aspects were found.

[Stability of home based care arrangements for people with dementia : Development of a consensus definition of stability using expert focus groups].

PubMed

von Kutzleben, Milena; Köhler, Kerstin; Dreyer, Jan; Holle, Bernhard; Roes, Martina

2017-04-01

The majority of people with dementia in Germany live at home. These informal care arrangements, which are mostly coordinated by informal carers, are the backbone of home-based dementia care. Creating and maintaining stability is an underlying theme in informal care; however, a definition of the complex phenomenon of 'stability' in this context is still lacking. The aim was to develop a working definition of stability of home-based care arrangements for people with dementia, which can be applied in current and future research projects at the German Center for Neurodegenerative Diseases in Witten (DZNE Witten) and others. Ensuing from prior research a preliminary version of the definition was formulated. This definition was discussed in a focus group of scientific experts with expertise in dementia research and care (n = 8). After data analysis using content analysis, the definition was revised during a scientific colloquium (n = 18) and a consensus was finally reached. There were four major themes which were considered by the experts as being relevant for the definition of stability: (1) creating and maintaining stability as a continuous adaptation process, (2) a qualitative component of stability, (3) persons with dementia and informal carers as pivotal players and (4) transitions to residential care. The working definition introduced in this article reflects the authors' understanding of the phenomenon of stability of home-based care arrangements for people with dementia. In times of increasing need for evidence-based interventions it is necessary to develop elaborated definitions of complex phenomena in order to be able to systematically evaluate the efficacy of interventions on the basis of a common understanding.

Mars Science Laboratory Rover Mobility Bushing Development

NASA Technical Reports Server (NTRS)

Riggs, Benjamin

2008-01-01

NASA s Mars Science Laboratory (MSL) Project will send a six-wheeled rover to Mars in 2009. The rover will carry a scientific payload designed to search for organic molecules on the Martian surface during its primary mission. This paper describes the development and testing of a bonded film lubricated bushing system to be used in the mobility system of the rover. The MSL Rover Mobility System contains several pivots that are tightly constrained with respect to mass and volume. These pivots are also exposed to relatively low temperatures (-135 C) during operation. The combination of these constraints led the mobility team to consider the use of solid film lubricated metallic bushings and dry running polymeric bushings in several flight pivot applications. A test program was developed to mitigate the risk associated with using these materials in critical pivots on the MSL vehicle. The program was designed to characterize bushing friction and wear performance over the expected operational temperature range (-135 C to +70 C). Seven different bushing material / lubricant combinations were evaluated to aid in the selection of the final flight pivot bushing material / lubricant combination.

Abasic pivot substitution harnesses target specificity of RNA interference

PubMed Central

Lee, Hye-Sook; Seok, Heeyoung; Lee, Dong Ha; Ham, Juyoung; Lee, Wooje; Youm, Emilia Moonkyung; Yoo, Jin Seon; Lee, Yong-Seung; Jang, Eun-Sook; Chi, Sung Wook

2015-01-01

Gene silencing via RNA interference inadvertently represses hundreds of off-target transcripts. Because small interfering RNAs (siRNAs) can function as microRNAs, avoiding miRNA-like off-target repression is a major challenge. Functional miRNA–target interactions are known to pre-require transitional nucleation, base pairs from position 2 to the pivot (position 6). Here, by substituting nucleotide in pivot with abasic spacers, which prevent base pairing and alleviate steric hindrance, we eliminate miRNA-like off-target repression while preserving on-target activity at ∼80–100%. Specifically, miR-124 containing dSpacer pivot substitution (6pi) loses seed-mediated transcriptome-wide target interactions, repression activity and biological function, whereas other conventional modifications are ineffective. Application of 6pi allows PCSK9 siRNA to efficiently lower plasma cholesterol concentration in vivo, and abolish potentially deleterious off-target phenotypes. The smallest spacer, C3, also shows the same improvement in target specificity. Abasic pivot substitution serves as a general means to harness the specificity of siRNA experiments and therapeutic applications. PMID:26679372

Conductor load bearing roller for a gas-insulated transmission line having a corrugated outer conductor

DOEpatents

Fischer, William H.; Yoon, Kue H.

1984-04-10

A gas-insulated transmission line includes a corrugated outer conductor, an inner conductor disposed within and insulated from the outer conductor by means of support insulators and an insulating gas, and a transport device for supporting and permitting movement of the inner conductor/insulating support assembly axially along the corrugated outer conductor without radial displacement. The transport device includes two movable contacts, such as skids or rollers, supported on a common pivot lever, the pivot lever being rotatably disposed about a pivot lever axis, which pivot lever axis is in turn disposed on the periphery of a support insulator or particle trap if one is used. The movable contacts are separated axially a distance equal to the axial distance between the peaks and valleys of the corrugations of the outer conductor and separated radially a distance equal to the radial distance between the peaks and valleys of the corrugations of the outer conductor. The transport device has the pivot lever axis disposed perpendicular to the direction of travel of the inner conductor/insulating support assembly.

A proposal for digital electro-optic switches with free-carrier dispersion effect and Goos-Hanchen shift in silicon-on-insulator waveguide corner mirror

NASA Astrophysics Data System (ADS)

Sun, DeGui

2013-09-01

In a silicon-on-insulator (SOI) waveguide corner mirror (WCM) structure, with the quantum process of a frustrated total internal reflection (FTIR) phenomenon and the time delay principle in the two-dimensional potential barrier tunneling process of a mass of particles, we derive an accurate physical model for the Goos-Hanchen (GH) shift of optical guided-mode in the FTIR process, and in principle match the GH shift jumping states with the independent guided-modes. Then, we propose and demonstrate a new regime of 1 × N digital optical switches with a matching state between the free-carrier dispersion (FCD) based refractive index modulation (RIM) of silicon to create a GH shift jumping function of a photonic signal at the reflecting interface and the independent guided-modes in the FTIR process, where a MOS-capacitor type electro-optic modulation regime is proposed and discussed to realize an effective FCD-based RIM. At the critical matching state, i.e., the incident of an optical beam is at the vicinity of Brewster angle in the WCM, a mini-change of refractive index of waveguide material can cause a great jump of GH shift along the FTIR reflecting interface, and further a 1 × N digital optical switching process could be realized. For a 350-500 nm single-mode rib waveguide made on the 220 nm CMOS-compatible SOI substrate and with the FCD effect based RIM of silicon crystal, a concentration variation of 1018-1019 cm-3 has caused a 0.5-2.5 μm GH shift of reflected beam, which is at 2-5 times of a mode-size and hence radically convinces an optical switching function with a 1 × 3-1 × 10 scale.

Transtibial vs anatomical single bundle technique for anterior cruciate ligament reconstruction: A Retrospective Cohort Study.

PubMed

Kilinc, Bekir Eray; Kara, Adnan; Oc, Yunus; Celik, Haluk; Camur, Savas; Bilgin, Emre; Erten, Yunus Turgay; Sahinkaya, Turker; Eren, Osman Tugrul

2016-05-01

Most of the ACL reconstruction is done with isometric single-bundle technique. Traditionally, surgeons were trained to use the transtibial technique (TT) for drilling the femoral tunnel. Our study compared the early postoperative period functional and clinical outcomes of patients who had ACL reconstruction with TT and patients who had ACL reconstruction with anatomical single-bundle technique (AT). Fifty-five patients who had ACL reconstruction and adequate follow-up between January 2010-December 2013 were included the study. Patients were grouped by their surgery technique. 28 patients included into anatomical single-bundle ACL reconstruction surgery group (group 1) and 27 patients were included into transtibial AC reconstruction group (group 2). Average age of patients in group 1 and group 2 was 28.3 ± 6, and 27.9 ± 6.4, respectively. Lachman and Pivot-shift tests were performed to patients. Laxity was measured by KT-1000 arthrometer test with 15, 20 and 30 pound power. All patients' muscle strength between both extremities were evaluated with Cybex II (Humac) at 60°/sec, 240°/sec frequencies with flexion and extension peak torque. The maximum force values of non-operated knee and the operated knee were compared to each other. Groups were evaluated by using International Knee Documentation Committee (IKDC) knee ligament healing Standard form, IKDC activity scale, modified Lysholm and Cincinnati evaluation forms. Return to work and exercise time of patients were compared. Functional and clinical outcomes of two groups were compared. NCSS 2007 and PASS 2008 Statistical Software programs were used for statistical analysis. There was no statistically significant difference between Lachman and Pivot-shift results (p > 0.01). Positive value of Pivot-shift test and incidence of anterior translation in Lachman test were higher in the patients who had TT. Lysholm activity level of patients who had TT, 33.3% (n = 9) were excellent, 51.9% (n = 14) were good and 14.8% (n = 4) were moderate; patients who had AT, 57.1% (n = 16) were excellent, 39.3% (n = 11) were good and 3.6% (n = 1) was good level. There was no statistically significant difference between Lysholm Activity level of the patients (p < 0.01). Lysholm Activity level of patients who had AT significantly higher than TT. There was no statistically significant difference between Modified Cincinnati activity level of the patients (p < 0.05). Modified Cincinnati activity level of patients who had AT were significantly higher than those had TT. There was no statistically significant difference between two groups with post treatment IKDC activity level (p < 0.01). Intense activity after treatment rate of patient who had AT was significantly higher than those had TT. There was statistically significant difference between Cybex extension-flexion 60 measurement and extension 240 measurement of the patients (p < 0.01). KT-1000 arthrometer test results with AT was better than the TT in antero-posterior translation of the knee kinematics at 20 and 30 pound of forces. Return to exercise time of patients who had TT was significantly higher than those had AT (p < 0.01). There was no statistically significant difference between return to work time of patients (p > 0.05). Single-bundle anatomic ACL reconstruction was better than the TT in term of clinical, functional, and laboratory results. We believe that AT ACL reconstruction will increase in use and traditional method which is TT ACL reconstruction surgery will decrease in the long term. Theoretically, anatomic relocation of the ACL can provide better knee kinematics. Copyright © 2016 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

Steering system for a train of rail-less vehicles

DOEpatents

Voight, Edward T.

1983-01-01

A steering system for use with a multiple vehicle train permits tracking without rails of one vehicle after another. This system is particularly useful for moving conveyor systems into and out of curved paths of room and pillar underground mine installations. The steering system features an elongated steering bar pivotally connected to each of adjacent vehicles at end portions of the bar permitting angular orientation of each vehicle in respect to the steering bar and other vehicles. Each end portion of the steering bar is linked to the near pair of vehicle wheels through wheel yoke pivot arms about king pin type pivots. Movement of the steering bar about its pivotal connection provides proportional turning of the wheels to effect steering and tracking of one vehicle following another in both forward and reverse directions.

Diauxic shift-dependent relocalization of decapping activators Dhh1 and Pat1 to polysomal complexes

PubMed Central

Drummond, Sheona P.; Hildyard, John; Firczuk, Helena; Reamtong, Onrapak; Li, Ning; Kannambath, Shichina; Claydon, Amy J.; Beynon, Robert J.; Eyers, Claire E.; McCarthy, John E. G.

2011-01-01

Dhh1 and Pat1 in yeast are mRNA decapping activators/translational repressors thought to play key roles in the transition of mRNAs from translation to degradation. However, little is known about the physical and functional relationships between these proteins and the translation machinery. We describe a previously unknown type of diauxic shift-dependent modulation of the intracellular locations of Dhh1 and Pat1. Like the formation of P bodies, this phenomenon changes the spatial relationship between components involved in translation and mRNA degradation. We report significant spatial separation of Dhh1 and Pat1 from ribosomes in exponentially growing cells. Moreover, biochemical analyses reveal that these proteins are excluded from polysomal complexes in exponentially growing cells, indicating that they may not be associated with active states of the translation machinery. In contrast, under diauxic growth shift conditions, Dhh1 and Pat1 are found to co-localize with polysomal complexes. This work suggests that Dhh1 and Pat1 functions are modulated by a re-localization mechanism that involves eIF4A. Pull-down experiments reveal that the intracellular binding partners of Dhh1 and Pat1 change as cells undergo the diauxic growth shift. This reveals a new dimension to the relationship between translation activity and interactions between mRNA, the translation machinery and decapping activator proteins. PMID:21712243

Glenoid fossa responses to mandibular lateral shift in growing rats.

PubMed

Liu, Chang; Kaneko, Sawa; Soma, Kunimichi

2007-07-01

To evaluate the morphological and histological responses of the glenoid fossa to mandibular lateral shift in growing rats. A resin plate was placed on the upper incisors of 4-week-old rats in the experimental groups to displace the mandible to the left during closure. The rats were killed after 2, 4, 8, and 12 weeks. The morphometric measurements were performed on dry skulls, and tissue blocks were processed for periodic acid and Schiff's reagent (PAS) staining to examine the new bone formation. Gross measurements showed asymmetry in both the position and size of the fossae between the two sides after 4 weeks of lateral shift. The glenoid fossa on the ipsilateral side was repositioned relatively backward, outward and upward compared with the contralateral side and control group, whereas the fossa on the contralateral side was relocated relatively forward and downward compared with the control group. The length of the fossa was smaller on the ipsilateral side than on contralateral side and control group. At 2 weeks, the amount of newly formed bone in the posterior region of the fossa was higher in the experimental group than the control group. It is suggested that the mandibular lateral shift causes asymmetry in the position and size of the glenoid fossa and that this phenomenon can be related to different bilateral directional new bone formation in the posterior region.

Chronodisruption and cancer

NASA Astrophysics Data System (ADS)

Erren, Thomas C.; Pape, H. Gerd; Reiter, Russel J.; Piekarski, Claus

2008-05-01

Research into health effects of chronodisruption (CD), a relevant disturbance of the circadian organization of physiology, endocrinology, metabolism and behaviour, is evolving at a rapid pace. With regard to malignancies, our synthesis of key experiments indicates that CD can play a causal role for cancer growth and tumor progression in animals. Moreover, our meta-analyses of 30 epidemiological studies evince that flight personnel and shift workers exposed to chronodisruption may have increased breast and prostate cancer risks: summary relative risks (RRs) for investigations of flight personnel and of shift workers suggested a 70 and 40% increase in the risk of breast cancer, respectively, and excess relative risks of prostate cancer in nine studies in flight personnel (40%) and in two studies in male shift workers. There was a remarkable indication of homogeneity of results from the individual studies that contribute to the average statistics. However, in view of doubts about whether the differing assessments of CD can really be regarded as valid reflections of the same causative phenomenon and the lack of control of covariates in the majority of studies, it is premature to conclude that the risk observations reflect a real, rather than spurious, association with CD. The challenge for future epidemiological investigations of the biologically plausible links between chronodisruption and human cancers is to conduct studies which appreciate details of transmeridian travelling, of shift work and of covariates for the development of the diseases.

Long-Term Experimental Acidification Drives Watershed Scale Shift in Dissolved Organic Matter Composition and Flux.

PubMed

SanClements, Michael D; Fernandez, Ivan J; Lee, Robert H; Roberti, Joshua A; Adams, Mary Beth; Rue, Garret A; McKnight, Diane M

2018-03-06

Over the last several decades dissolved organic carbon concentrations (DOC) in surface waters have increased throughout much of the northern hemisphere. Several hypotheses have been proposed regarding the drivers of this phenomenon including decreased sulfur (S) deposition working via an acidity- change mechanism. Using fluorescence spectroscopy and data from two long-term (24+ years at completion of this study) whole watershed acidification experiments, that is, the Bear Brook Watershed in Maine (BBWM) and Fernow Experimental Forest in West Virginia (FEF) allowed us to control for factors other than the acidity-change mechanism (e.g., differing vegetation, shifting climate), resulting in the first study we are aware of where the acidity change mechanism could be experimentally isolated at the whole ecosystem and decadal scales as the driver of shifts in DOM dynamics. The multidecadal record of stream chemistry at BBWM demonstrates a significantly lower DOC concentration in the treated compared to the reference watershed. Additionally, at both BBWM and FEF we found significant and sustained differences in stream fluorescence index (FI) between the treated and reference watersheds, with the reference watersheds demonstrating a stronger terrestrial DOM signature. These data, coupled with evidence of pH shifts in upper soil horizons support the hypotheses that declines in S deposition are driving changes in the solubility of soil organic matter and increased flux of terrestrial DOC to water bodies.

Is Set Shifting Really Impaired in Trait Anxiety? Only When Switching Away from an Effortfully Established Task Set

PubMed Central

Gustavson, Daniel E.; Altamirano, Lee J.; Johnson, Daniel P.; Whisman, Mark A.; Miyake, Akira

2016-01-01

The current study investigated whether trait anxiety was systematically related to task-set shifting performance, using a task-switching paradigm in which one task was more attentionally demanding than the other. Specifically, taking advantage of a well-established phenomenon known as asymmetric switch costs, we tested the hypothesis that the association between trait anxiety and task-set shifting is most clearly observed when individuals must switch away from a more attentionally demanding task for which it was necessary to effortfully establish an appropriate task set. Ninety-one young adults completed an asymmetric switching task and trait-level mood questionnaires. Results indicated that higher levels of trait anxiety were systematically associated with greater asymmetry in reaction-time (RT) switch costs. Specifically, the RT costs for switching from the more attentionally demanding task to the less demanding task were significantly greater with higher levels of trait anxiety, whereas the RT costs for switching in the opposite direction were not significantly associated with trait anxiety levels. Further analyses indicated that these associations were not attributable to comorbid dysphoria or worry. These results suggest that levels of trait anxiety may not be related to general set-shifting ability per se, but, rather, that anxiety-specific effects may primarily be restricted to when one must efficiently switch away from (or let go of) an effortfully established task set. PMID:27429194

Pipe crawler apparatus

DOEpatents

Hovis, Gregory L.; Erickson, Scott A.; Blackmon, Bruce L.

2002-01-01

A pipe crawler apparatus particularly useful for 3-inch and 4-inch diameter pipes is provided. The pipe crawler apparatus uses a gripping apparatus in which a free end of a piston rod is modified with a bearing retaining groove. Bearings, placed within the groove, are directed against a camming surface of three respective pivoting support members. The non-pivoting ends of the support members carry a foot-like gripping member that, upon pivoting of the support member, engages the interior wall of the pipe.

A PKM2 signature in the failing heart

PubMed Central

Rees, Meredith L.; Subramaniam, Janani; Li, Yuanteng; Hamilton, Dale J.; Frazier, O. Howard; Taegtmeyer, Heinrich

2015-01-01

A salient feature of the failing heart is metabolic remodeling towards predominant glucose metabolism and activation of the fetal gene program. Sunitinib is a multitargeted receptor tyrosine kinase inhibitor used for the treatment of highly vascularized tumors. In diabetic patients, sunitinib significantly decreases blood glucose. However, a considerable proportion of sunitinib-treated patients develop cardiac dysfunction or failure. We asked whether sunitinib treatment results in shift towards glycolysis in the heart. Glucose uptake by the heart was increased fivefold in mice treated with sunitinib. Transcript analysis by qPCR revealed an induction of genes associated with glycolysis and reactivation of the fetal gene program. Additionally, we observed a shift in the enzyme pyruvate kinase from the adult M1 (PKM1) isoform to the fetal M2 (PKM2) isoform, a hallmark of the Warburg Effect. This novel observation led us to examine whether a similar shift occurs in human heart failure. Examination of tissue from patients with heart failure similarly displayed an induction of PKM2. Moreover, this phenomenon was partially reversed following mechanical unloading. We propose that pyruvate kinase isoform switching represents a novel feature of the fetal gene program in the failing heart. PMID:25735978

Electrochemical and optical study of carotenoids in TX 100 micelles: Electron transfer and a large blue shift

DOE Office of Scientific and Technical Information (OSTI.GOV)

He, Z.; Kispert, L.D.

1999-10-21

The first oxidation waves of 8{prime}-apo-{beta}-caroten-8{prime}-al (I) and 8{prime}-apo-{beta}-caroten-8{prime}nitrile (II) in TX100 micelles are clearly observed in their cyclic voltammograms (CVs). The CV of {beta}-carotene (III) in TX100 micelles shows that III is not oxidized. It is proposed that the hydrophobic barrier of the micelle is an important reason for the failure to oxidize III, which is totally located in the hydrophobic center of the micelle. The oxidation of I and II demonstrates that electrons can be transferred through the terminal groups over a distance of ca. 22 {angstrom}. An unusually large blue band shift (100 nm, relative to thatmore » in CH{sub 2}Cl{sub 2}) is observed in the optical absorption spectrum of 7{prime}-apo-7{prime},7{prime}-dicyano-{beta}-carotene (IV) in TX100 micelles. This phenomenon is not observed in the absorption spectra of other studied carotenoids. A change in the ground-state electronic structure of IV, due to the influence of water near the terminal dicyanomethylidene group, is proposed to be the major reason for this large band shift.« less

Giant Dirac point shift of graphene phototransistors by doped silicon substrate current

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shimatani, Masaaki; Ogawa, Shinpei, E-mail: Ogawa.Shimpei@eb.MitsubishiElectric.co.jp; Fujisawa, Daisuke

2016-03-15

Graphene is a promising new material for photodetectors due to its excellent optical properties and high-speed response. However, graphene-based phototransistors have low responsivity due to the weak light absorption of graphene. We have observed a giant Dirac point shift upon white light illumination in graphene-based phototransistors with n-doped Si substrates, but not those with p-doped substrates. The source-drain current and substrate current were investigated with and without illumination for both p-type and n-type Si substrates. The decay time of the drain-source current indicates that the Si substrate, SiO{sub 2} layer, and metal electrode comprise a metal-oxide-semiconductor (MOS) capacitor due tomore » the presence of defects at the interface between the Si substrate and SiO{sub 2} layer. The difference in the diffusion time of the intrinsic major carriers (electrons) and the photogenerated electron-hole pairs to the depletion layer delays the application of the gate voltage to the graphene channel. Therefore, the giant Dirac point shift is attributed to the n-type Si substrate current. This phenomenon can be exploited to realize high-performance graphene-based phototransistors.« less

Highly sensitive torsion sensor based on long period fiber grating fabricated by femtosecond laser pulses

NASA Astrophysics Data System (ADS)

Dong, Xinran; Xie, Zheng; Song, Yuxin; Yin, Kai; Luo, Zhi; Duan, Ji'an; Wang, Cong

2017-12-01

A highly sensitive torsion sensor based on long period fiber grating (LPFG) fabricated by 800 nm femtosecond laser pulses is proposed and demonstrated. LPFG with an attenuation depth of ∼14 dB is achieved within the wavelength range of 1425-1575 nm. The experiment results show that the LP02 and LP03 resonant wavelengths experience red-shift when the twist direction is clockwise while they occur blue-shift in the twist counterclockwise direction as the twist rate increases. However, the LP04 resonant wavelength is always shifted toward shorter wavelength independently of the twist directions and higher twist sensitivity is observed. In addition, the loss peak amplitude of LPFG shows a tendency to decrease with the twist rate increases whether the LPFG is twisted clockwise or counterclockwise. Meanwhile, the resonant wavelength occurs splitting phenomenon in the case of higher twist rate as well as the high order resonant wavelength performs more significantly. Additionally, the sensor shows a twist sensitivity as high as 118.7 pm/(rad/m) in the range of -105 to -52.5 rad/m and that of 181.7 pm/(rad/m) in the range of 52.5-105 rad/m.

Motivated emotion and the rally around the flag effect: liberals are motivated to feel collective angst (like conservatives) when faced with existential threat.

PubMed

Porat, Roni; Tamir, Maya; Wohl, Michael J A; Gur, Tamar; Halperin, Eran

2018-04-18

A careful look at societies facing threat reveals a unique phenomenon in which liberals and conservatives react emotionally and attitudinally in a similar manner, rallying around the conservative flag. Previous research suggests that this rally effect is the result of liberals shifting in their attitudes and emotional responses toward the conservative end. Whereas theories of motivated social cognition provide a motivation-based account of cognitive processes (i.e. attitude shift), it remains unclear whether emotional shifts are, in fact, also a motivation-based process. Herein, we propose that under threat, liberals are motivated to feel existential concern about their group's future vitality (i.e. collective angst) to the same extent as conservatives, because this group-based emotion elicits support for ingroup protective action. Within the context of the Palestinian-Israeli conflict, we tested and found support for this hypothesis both inside (Study 1) and outside (Study 2) the laboratory. We did so using a behavioural index of motivation to experience collective angst. We discuss the implications of our findings for understanding motivated emotion regulation in the context of intergroup threat.

North-South Asymmetric Solar Cycle Evolution: Signatures in the Photosphere and Consequences in the Corona

NASA Astrophysics Data System (ADS)

Virtanen, I. I.; Mursula, K.

2014-02-01

The heliospheric current sheet is the continuum of the coronal magnetic equator that divides the heliospheric magnetic field into two sectors (polarities). Several recent studies have shown that the heliospheric current sheet is southward shifted during approximately 3 years in the solar declining phase (the so-called bashful ballerina phenomenon). In this article we study the hemispherical asymmetry in the photospheric and coronal magnetic fields using Wilcox Solar Observatory measurements of the photospheric magnetic field since 1976 as well as the potential field source surface model. Multipole analysis of the photospheric magnetic field shows that during the late declining phase of solar cycles since the 1970s, the "bashful ballerina phenomenon" is a consequence of the g^{0}_{2} quadrupole term, signed oppositely to the dipole moment. Surges of new flux transport magnetic field from low latitudes to the poles, thus leading to a systematically varying contribution to the g^{0}_{2}-term from different latitudes. In the case of a north-south asymmetric flux production, this is seen as a quadrupole contribution traveling toward higher latitudes. When the quadrupole term is largest, the main contribution comes from the polar latitudes. At least during the four recent solar cycles, the g^{0}_{2}-term arises because the magnitude of the southern polar field is larger than the magnitude found in the north in the declining phase of the cycle. In the heliosphere this hemispheric asymmetry of the coronal fields is seen as a southward shift of the heliospheric current sheet by about 2°.

Beam Steering Devices Reduce Payload Weight

NASA Technical Reports Server (NTRS)

2012-01-01

Scientists have long been able to shift the direction of a laser beam, steering it toward a target, but often the strength and focus of the light is altered. For precision applications, where the quality of the beam cannot be compromised, scientists have typically turned to mechanical steering methods, redirecting the source of the beam by swinging the entire laser apparatus toward the target. Just as the mechanical methods used for turning cars has evolved into simpler, lighter, power steering methods, so has the means by which researchers can direct lasers. Some of the typical contraptions used to redirect lasers are large and bulky, relying on steering gimbals pivoted, rotating supports to shift the device toward its intended target. These devices, some as large and awkward as a piece of heavy luggage, are subject to the same issues confronted by mechanical parts: Components rub, wear out, and get stuck. The poor reliability and bulk not to mention the power requirements to run one of the machines have made mechanical beam steering components less than ideal for use in applications where weight, bulk, and maneuverability are prime concerns, such as on an unmanned aerial vehicle (UAV) or a microscope. The solution to developing reliable, lighter weight, nonmechanical steering methods to replace the hefty steering boxes was to think outside the box, and a NASA research partner did just that by developing a new beam steering method that bends and redirects the beam, as opposed to shifting the entire apparatus. The benefits include lower power requirements, a smaller footprint, reduced weight, and better control and flexibility in steering capabilities. Such benefits are realized without sacrificing aperture size, efficiency, or scanning range, and can be applied to myriad uses: propulsion systems, structures, radiation protection systems, and landing systems.

High-fat-diet-mediated dysbiosis promotes intestinal carcinogenesis independently of obesity.

PubMed

Schulz, Manon D; Atay, Ciğdem; Heringer, Jessica; Romrig, Franziska K; Schwitalla, Sarah; Aydin, Begüm; Ziegler, Paul K; Varga, Julia; Reindl, Wolfgang; Pommerenke, Claudia; Salinas-Riester, Gabriela; Böck, Andreas; Alpert, Carl; Blaut, Michael; Polson, Sara C; Brandl, Lydia; Kirchner, Thomas; Greten, Florian R; Polson, Shawn W; Arkan, Melek C

2014-10-23

Several features common to a Western lifestyle, including obesity and low levels of physical activity, are known risk factors for gastrointestinal cancers. There is substantial evidence suggesting that diet markedly affects the composition of the intestinal microbiota. Moreover, there is now unequivocal evidence linking dysbiosis to cancer development. However, the mechanisms by which high-fat diet (HFD)-mediated changes in the microbial community affect the severity of tumorigenesis in the gut remain to be determined. Here we demonstrate that an HFD promotes tumour progression in the small intestine of genetically susceptible, K-ras(G12Dint), mice independently of obesity. HFD consumption, in conjunction with K-ras mutation, mediated a shift in the composition of the gut microbiota, and this shift was associated with a decrease in Paneth-cell-mediated antimicrobial host defence that compromised dendritic cell recruitment and MHC class II molecule presentation in the gut-associated lymphoid tissues. When butyrate was administered to HFD-fed K-ras(G12Dint) mice, dendritic cell recruitment in the gut-associated lymphoid tissues was normalized, and tumour progression was attenuated. Importantly, deficiency in MYD88, a signalling adaptor for pattern recognition receptors and Toll-like receptors, blocked tumour progression. The transfer of faecal samples from HFD-fed mice with intestinal tumours to healthy adult K-ras(G12Dint) mice was sufficient to transmit disease in the absence of an HFD. Furthermore, treatment with antibiotics completely blocked HFD-induced tumour progression, suggesting that distinct shifts in the microbiota have a pivotal role in aggravating disease. Collectively, these data underscore the importance of the reciprocal interaction between host and environmental factors in selecting a microbiota that favours carcinogenesis, and they suggest that tumorigenesis is transmissible among genetically predisposed individuals.

Regional hydro-climatic impacts of contemporary Amazonian deforestation

NASA Astrophysics Data System (ADS)

Khanna, Jaya

More than 17% of the Amazon rainforest has been cleared in the past three decades triggering important climatological and societal impacts. This thesis is devoted to identifying and explaining the regional hydroclimatic impacts of this change employing multidecadal satellite observations and numerical simulations providing an integrated perspective on this topic. The climatological nature of this study motivated the implementation and application of a cloud detection technique to a new geostationary satellite dataset. The resulting sub daily, high spatial resolution, multidecadal time series facilitated the detection of trends and variability in deforestation triggered cloud cover changes. The analysis was complemented by satellite precipitation, reanalysis and ground based datasets and attribution with the variable resolution Ocean-Land-Atmosphere-Model. Contemporary Amazonian deforestation affects spatial scales of hundreds of kilometers. But, unlike the well-studied impacts of a few kilometers scale deforestation, the climatic response to contemporary, large scale deforestation is neither well observed nor well understood. Employing satellite datasets, this thesis shows a transition in the regional hydroclimate accompanying increasing scales of deforestation, with downwind deforested regions receiving 25% more and upwind deforested regions receiving 25% less precipitation from the deforested area mean. Simulations robustly reproduce these shifts when forced with increasing deforestation alone, suggesting a negligible role of large-scale decadal climate variability in causing the shifts. Furthermore, deforestation-induced surface roughness variations are found necessary to reproduce the observed spatial patterns in recent times illustrating the strong scale-sensitivity of the climatic response to Amazonian deforestation. This phenomenon, inconsequential during the wet season, is found to substantially affect the regional hydroclimate in the local dry and parts of transition seasons, hence occurring in atmospheric conditions otherwise less conducive to thermal convection. Evidence of this phenomenon is found at two large scale deforested areas considered in this thesis. Hence, the 'dynamical' mechanism, which affects the seasons most important for regional ecology, emerges as an impactful convective triggering mechanism. The phenomenon studied in this thesis provides context for thinking about the climate of a future, more patchily forested Amazonia, by articulating relationships between climate and spatial scales of deforestation.

18. Detail view of central pivot pier, drive gear rack, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

18. Detail view of central pivot pier, drive gear rack, and stabilizing wheel, looking southwest - India Point Railroad Bridge, Spanning Seekonk River between Providence & East Providence, Providence, Providence County, RI

Detail of plate and gears on center pivot. From civilian ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Detail of plate and gears on center pivot. From civilian land. Looking north. - Naval Supply Annex Stockton, Daggett Road Bridge, Daggett Road traversing Burns Cut Off, Stockton, San Joaquin County, CA

How does a modal shift from short car trips to cycling affect road safety?

PubMed

Schepers, J P; Heinen, E

2013-01-01

Governments aim to promote a shift from car to bicycle, but concerns about road safety seem to represent an important argument against this encouragement. This study examines the road safety impact of a modal shift from short car trips to cycling in Dutch municipalities. The road safety effect is estimated using Accident Prediction Models (APMs) that account for the non-linearity of risk. APMs are developed utilizing Negative Binomial regression. This study is the first to develop APMs using crash and mobility data from municipalities, and utilizing these models to estimate the effects of changing modal splits of current car and bicycle use to modal splits that actually exist in these municipalities. The results suggest that, under conditions such as in Dutch municipalities, transferring short trips made by cars to bicycles does not change the number of fatalities, but increases the number of serious road injuries. The neutral effect on fatalities, despite the high fatality risk for cyclists, can be explained by there being fewer cars on the road to pose a risk to others, the shorter length of bicycle trips compared to the car trips they replace, and the "safety in numbers" phenomenon. The rise in the number of serious road injuries is due wholly to the high number of cycling crashes with no other vehicle involved. The effect of a modal shift is dependent on the age of the population in which the shift is concentrated, and can be influenced by measures affecting cyclists' injury risk. Copyright © 2012 Elsevier Ltd. All rights reserved.

Curvature of the localized surface plasmon resonance peak.

PubMed

Chen, Peng; Liedberg, Bo

2014-08-05

Localized surface plasmon resonance (LSPR) occurring in noble metal nanoparticles (e.g., Au) is a widely used phenomenon to report molecular interactions. Traditional LSPR sensors typically monitor shifts in the peak position or extinction in response to local refractive index changes in the close vicinity of the nanoparticle surface. The ability to resolve minute shifts/extinction changes is to a large extent limited by instrumental noise. A new strategy to evaluate LSPR responses utilizing changes in the shape of the extinction spectrum (the curvature) is proposed. The response of curvature to refractive index changes is investigated theoretically using Mie theory and an analytical expression relating the curvature to the refractive index is presented. The experimentally derived curvatures for 13 nm spherical gold nanoparticles (AuNPs) exposed to solvents with different bulk refractive indices confirm the theoretical predictions. Moreover, both the calculated and experimental findings suggest that the curvature is approximately a linear function of refractive index in regimes relevant to bio and chemical sensing. We demonstrate that curvature is superior over peak shift and extinction both in terms of signal-to-noise (S/N) ratio and reliability of LSPR sensors. With a curvature, one could readily monitor submonolayer adsorption of a low molecular weight thiol molecule (M(w) = 458.6) onto 13 nm AuNPs. It is also worthwhile mentioning that curvature is virtually insensitive to instrumental instabilities and artifacts occurring during measurement. Instabilities such as baseline tilt and shift, shift in peak position as well as sharp spikes/steps in the extinction spectra do not induce artifacts in the sensorgrams of curvature.

Steam separator latch assembly

DOEpatents

Challberg, Roy C.; Kobsa, Irvin R.

1994-01-01

A latch assembly removably joins a steam separator assembly to a support flange disposed at a top end of a tubular shroud in a nuclear reactor pressure vessel. The assembly includes an annular head having a central portion for supporting the steam separator assembly thereon, and an annular head flange extending around a perimeter thereof for supporting the head to the support flange. A plurality of latches are circumferentially spaced apart around the head flange with each latch having a top end, a latch hook at a bottom end thereof, and a pivot support disposed at an intermediate portion therebetween and pivotally joined to the head flange. The latches are pivoted about the pivot supports for selectively engaging and disengaging the latch hooks with the support flange for fixedly joining the head to the shroud or for allowing removal thereof.

Steam separator latch assembly

DOEpatents

Challberg, R.C.; Kobsa, I.R.

1994-02-01

A latch assembly removably joins a steam separator assembly to a support flange disposed at a top end of a tubular shroud in a nuclear reactor pressure vessel. The assembly includes an annular head having a central portion for supporting the steam separator assembly thereon, and an annular head flange extending around a perimeter thereof for supporting the head to the support flange. A plurality of latches are circumferentially spaced apart around the head flange with each latch having a top end, a latch hook at a bottom end thereof, and a pivot support disposed at an intermediate portion therebetween and pivotally joined to the head flange. The latches are pivoted about the pivot supports for selectively engaging and disengaging the latch hooks with the support flange for fixedly joining the head to the shroud or for allowing removal thereof. 12 figures.

Effects of off-axis elliptical training on reducing pain and improving knee function in individuals with patellofemoral pain

PubMed Central

Tsai, Liang-Ching; Lee, Song Joo; Yang, Aaron J.; Ren, Yupeng; Press, Joel M.; Zhang, Li-Qun

2014-01-01

Objective To examine whether an off-axis elliptical training program reduces pain and improves knee function in individuals with patellofemoral pain (PFP). Design Controlled laboratory study, pre-test-post-test. Setting University rehabilitation center. Participants Twelve adult subjects with PFP. Interventions Subjects with PFP completed an exercise program consisting of 18 sessions of lower extremity off-axis training using a custom-made elliptical trainer that allows frontal-plane sliding and transverse-plane pivoting of the footplates. Main Outcome Measures Changes in knee pain and function post-training and 6 weeks following training were evaluated using the Knee Injury and Osteoarthritis Outcome Score (KOOS) and International Knee Documentation Committee (IKDC) scores. Lower extremity off-axis control was assessed by pivoting and sliding instability, calculated as the root mean square (RMS) of the footplate pivoting angle and sliding distance during elliptical exercise. Subjects’ single-leg hop distance and proprioception in detecting lower extremity pivoting motion were also evaluated. Results Subjects reported significantly greater KOOS and IKDC scores (increased by 12–18 points) and hop distance (increased by 0.2 m) following training. A significant decrease in the pivoting and sliding RMS was also observed following training. Additionally, subjects with PFP demonstrated improved pivoting proprioception when tested under a minimum-weight-bearing position. Conclusions An off-axis elliptical training program was effective in enhancing lower extremity neuromuscular control on the frontal and transverse planes, reducing pain and improving knee function in persons with PFP. PMID:25591131

The relationship between mucosal immunity, nasopharyngeal carriage, asymptomatic transmission and the resurgence of Bordetella pertussis

PubMed Central

Gill, Christopher; Rohani, Pejman; Thea, Donald M

2017-01-01

The incidence of whooping cough in the US has been rising slowly since the 1970s, but the pace of this has accelerated sharply since acellular pertussis vaccines replaced the earlier whole cell vaccines in the late 1990s. A similar trend occurred in many other countries, including the UK, Canada, Australia, Ireland, and Spain, following the switch to acellular vaccines. The key question is why. Two leading theories (short duration of protective immunologic persistence and evolutionary shifts in the pathogen to evade the vaccine) explain some but not all of these shifts, suggesting that other factors may also be important. In this synthesis, we argue that sterilizing mucosal immunity that blocks or abbreviates the duration of nasopharyngeal carriage of Bordetella pertussis and impedes person-to-person transmission (including between asymptomatically infected individuals) is a critical factor in this dynamic. Moreover, we argue that the ability to induce such mucosal immunity is fundamentally what distinguishes whole cell and acellular pertussis vaccines and may be pivotal to understanding much of the resurgence of this disease in many countries that adopted acellular vaccines. Additionally, we offer the hypothesis that observed herd effects generated by acellular vaccines may reflect a modification of disease presentation leading to reduced potential for transmission by those already infected, as opposed to inducing resistance to infection among those who have been exposed. PMID:28928960

Protein-ion binding process on finite macromolecular concentration. A Poisson-Boltzmann and Monte Carlo study.

PubMed

de Carvalho, Sidney Jurado; Fenley, Márcia O; da Silva, Fernando Luís Barroso

2008-12-25

Electrostatic interactions are one of the key driving forces for protein-ligands complexation. Different levels for the theoretical modeling of such processes are available on the literature. Most of the studies on the Molecular Biology field are performed within numerical solutions of the Poisson-Boltzmann Equation and the dielectric continuum models framework. In such dielectric continuum models, there are two pivotal questions: (a) how the protein dielectric medium should be modeled, and (b) what protocol should be used when solving this effective Hamiltonian. By means of Monte Carlo (MC) and Poisson-Boltzmann (PB) calculations, we define the applicability of the PB approach with linear and nonlinear responses for macromolecular electrostatic interactions in electrolyte solution, revealing some physical mechanisms and limitations behind it especially due the raise of both macromolecular charge and concentration out of the strong coupling regime. A discrepancy between PB and MC for binding constant shifts is shown and explained in terms of the manner PB approximates the excess chemical potentials of the ligand, and not as a consequence of the nonlinear thermal treatment and/or explicit ion-ion interactions as it could be argued. Our findings also show that the nonlinear PB predictions with a low dielectric response well reproduce the pK shifts calculations carried out with an uniform dielectric model. This confirms and completes previous results obtained by both MC and linear PB calculations.

Interleukin-35 administration counteracts established murine type 1 diabetes--possible involvement of regulatory T cells.

PubMed

Singh, Kailash; Kadesjö, Erik; Lindroos, Julia; Hjort, Marcus; Lundberg, Marcus; Espes, Daniel; Carlsson, Per-Ola; Sandler, Stellan; Thorvaldson, Lina

2015-07-30

The anti-inflammatory cytokine IL-35 is produced by regulatory T (Treg) cells to suppress autoimmune and inflammatory responses. The role of IL-35 in type 1 diabetes (T1D) remains to be answered. To elucidate this, we investigated the kinetics of Treg cell response in the multiple low dose streptozotocin induced (MLDSTZ) T1D model and measured the levels of IL-35 in human T1D patients. We found that Treg cells were increased in MLDSTZ mice. However, the Treg cells showed a decreased production of anti-inflammatory (IL-10, IL-35, TGF-β) and increased pro-inflammatory (IFN-γ, IL-2, IL-17) cytokines, indicating a phenotypic shift of Treg cells under T1D condition. IL-35 administration effectively both prevented development of, and counteracted established MLDSTZ T1D, seemingly by induction of Eos expression and IL-35 production in Treg cells, thus reversing the phenotypic shift of the Treg cells. IL-35 administration reversed established hyperglycemia in NOD mouse model of T1D. Moreover, circulating IL-35 levels were decreased in human T1D patients compared to healthy controls. These findings suggest that insufficient IL-35 levels play a pivotal role in the development of T1D and that treatment with IL-35 should be investigated in treatment of T1D and other autoimmune diseases.

Non-binding conductor load bearing roller for a gas-insulated transmission line having a corrugated outer conductor

DOEpatents

Fischer, William H.

1984-01-01

A gas-insulated transmission line includes a corrugated outer conductor, an inner conductor disposed within and insulated from the outer conductor by means of support insulators and an insulating gas, and a non-binding transport device for supporting and permitting movement of the inner conductor/insulating support assembly axially along the corrugated outer conductor without radial displacement and for moving without binding along corrugations of any slope less than vertical. The transport device includes two movable contacts, such as skids or rollers, supported on a common pivot lever, the pivot lever being rotatably disposed about a pivot lever axis, which pivot lever axis is in turn disposed on the periphery of a support insulator or particle trap if one is used. The movable contacts are separated axially a distance equal to the axial distance between the peaks and valleys of the corrugations of the outer conductor and separated radially a distance equal to the radial distance between the peaks and valleys of the corrugations of the outer conductor. The transport device has the pivot lever axis disposed parallel to the motion of travel of the inner conductor/insulating support assembly.

How Much Do Hospitals Cost Shift? A Review of the Evidence

PubMed Central

Frakt, Austin B

2011-01-01

Context: Hospital cost shifting—charging private payers more in response to shortfalls in public payments—has long been part of the debate over health care policy. Despite the abundance of theoretical and empirical literature on the subject, it has not been critically reviewed and interpreted since Morrisey did so nearly fifteen years ago. Much has changed since then, in both empirical technique and the health care landscape. This article examines the theoretical and empirical literature on cost shifting since 1996, synthesizes the predominant findings, suggests their implications for the future of health care costs, and puts them in the current policy context. Methods: The relevant literature was identified by database search. Papers describing policies were considered first, since policy shapes the health care market in which cost shifting may or may not occur. Theoretical works were examined second, as theory provides hypotheses and structure for empirical work. The empirical literature was analyzed last in the context of the policy environment and in light of theoretical implications for appropriate econometric specification. Findings: Most of the analyses and commentary based on descriptive, industrywide hospital payment-to-cost margins by payer provide a false impression that cost shifting is a large and pervasive phenomenon. More careful theoretical and empirical examinations suggest that cost shifting can and has occurred, but usually at a relatively low rate. Margin changes also are strongly influenced by the evolution of hospital and health plan market structures and changes in underlying costs. Conclusions: Policymakers should view with a degree of skepticism most hospital and insurance industry claims of inevitable, large-scale cost shifting. Although some cost shifting may result from changes in public payment policy, it is just one of many possible effects. Moreover, changes in the balance of market power between hospitals and health care plans also significantly affect private prices. Since they may increase hospitals’ market power, provisions of the new health reform law that may encourage greater provider integration and consolidation should be implemented with caution. PMID:21418314

Center pivot, showing substantial beams that support the trusses. Looking ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Center pivot, showing substantial beams that support the trusses. Looking north from civilian land. - Naval Supply Annex Stockton, Daggett Road Bridge, Daggett Road traversing Burns Cut Off, Stockton, San Joaquin County, CA

The Pivot to Asia: Can It Serve as the Foundation for American Grand Strategy in the 21st Century

DTIC Science & Technology

in which the Obama Administration cannot make a definitive choice in favor of one of these schools of thought, it has opted for a policy of hedging...also discusses the problems that the Obama Administration has been forced to confront in other placese.g., Ukraine, Libya, Syria, etc.that have...complicated its efforts to keep its focus on the pivot strategy in the IAP region. He concludes with some lessons for strategists, derived from the Obama teams experience with the pivot.

Bracing can partially limit tibial rotation during stressful activities after anterior crucial ligament reconstruction with a hamstring graft.

PubMed

Giotis, D; Paschos, N K; Zampeli, F; Pappas, E; Mitsionis, G; Georgoulis, A D

2016-09-01

Hamstring graft has substantial differences with BPTB graft regarding initial mechanical strength, healing sequence, and vascularization, which may imply that a different approach during rehabilitation period is required. The purpose of this study was to investigate the influence of knee bracing on tibial rotation in ACL-reconstructed patients with a hamstring autograft during high loading activities. The hypothesis was that there would be a decrease in tibial rotation in the ACL-reconstructed braced knee as compared to the unbraced knee. Twenty male patients having undergone unilateral ACL reconstruction with a semitendinosus/gracilis autograft were assessed. Kinematic data were collected with an eight-camera optoelectronic system during two stressful tasks: (1) descending from a stair and subsequent pivoting; and (2) landing from a platform and subsequent pivoting. In each patient, three different experimental conditions were evaluated: (A) wearing a prophylactic brace (braced condition); (B) wearing a patellofemoral brace (sleeved condition); (C) without brace (unbraced condition). The intact knee without brace served as a control. Tibial rotation was significantly lower in the intact knee compared to all three conditions of the ACL-reconstructed knee (P≤0.01 for both tasks). Presence of a brace or sleeve resulted in lower tibial rotation than in the unbraced condition (p=0.003 for descending/pivot and P=0.0004 for landing/pivot). The braced condition resulted in lower rotation than the sleeved condition for descending/pivoting (P=0.031) while no differences were found for landing/pivoting (P=0.230). Knee bracing limited the excessive tibial rotation during pivoting under high loading activities in ACL-reconstructed knees with a hamstring graft. This partial restoration of normal kinematics may have a potential beneficial effect in patients recovering from ACL reconstruction with a hamstring autograft. Level III, case-control therapeutic study. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Origin and Characteristics of High Shannon Entropy at the Pivot of Locally Stable Rotors: Insights from Computational Simulation

PubMed Central

Gharaviri, Ali; Brooks, Anthony; Chapman, Darius; Lau, Dennis H.; Roberts-Thomson, Kurt C.; Sanders, Prashanthan

2014-01-01

Background Rotors are postulated to maintain cardiac fibrillation. Despite the importance of bipolar electrograms in clinical electrophysiology, few data exist on the properties of bipolar electrograms at rotor sites. The pivot of a spiral wave is characterized by relative uncertainty of wavefront propagation direction compared to the periphery. The bipolar electrograms used in electrophysiology recording encode information on both direction and timing of approaching wavefronts. Objective To test the hypothesis that bipolar electrograms from the pivot of rotors have higher Shannon entropy (ShEn) than electrograms recorded at the periphery due to the spatial dynamics of spiral waves. Methods and Results We studied spiral wave propagation in 2-dimensional sheets constructed using a simple cell automaton (FitzHugh-Nagumo), atrial (Courtemanche-Ramirez-Nattel) and ventricular (Luo-Rudy) myocyte cell models and in a geometric model spiral wave. In each system, bipolar electrogram recordings were simulated, and Shannon entropy maps constructed as a measure of electrogram information content. ShEn was consistently highest in the pivoting region associated with the phase singularity of the spiral wave. This property was consistently preserved across; (i) variation of model system (ii) alterations in bipolar electrode spacing, (iii) alternative bipolar electrode orientation (iv) bipolar electrogram filtering and (v) in the presence of rotor meander. Directional activation plots demonstrated that the origin of high ShEn at the pivot was the directional diversity of wavefront propagation observed in this location. Conclusions The pivot of the rotor is consistently associated with high Shannon entropy of bipolar electrograms despite differences in action potential model, bipolar electrode spacing, signal filtering and rotor meander. Maximum ShEn is co-located with the pivot for rotors observed in the bipolar electrogram recording mode, and may be an intrinsic property of spiral wave dynamic behaviour. PMID:25401331

Falling Evaporating Bodies around Beta Pictoris

NASA Astrophysics Data System (ADS)

Beust, H.

2014-09-01

The edge-on orientation of the beta Pictoris disk as viewed from the Earth enabled the detection of its gaseous counterpart by absorption spectroscopy. This was done as early as 1985 (Vidal-Madjar et al.). Surprisingly, the detected circumstellar absorptions in Ca II, Mg II, etc... lines appeared to often present, next to a central stable component, highly time- variable additional features, Doppler shifted by a few tens, sometimes up to a few hundreds km/s. A huge sample of such features, sometimes presenting very different shapes, has been recorded since that time, especially in the last 10 years thanks to the survey by the HARPS spectrograph. Modeling work in the late 1980's led to propose that these transient spectral events could be due to star-grazing, evaporating planetesimals arising from the disk, that cross the line of sight close to periastron. The absorption components would be due to the gaseous coma around the object, and the Doppler shift to the projection of its velocity onto the line of sight. This model has been thus termed the ÓFalling Evaporating BodiesÓ (FEB) model. Detailed modeling and simulations (Beust et al. 1990, 1996; Karmann et al. 2001, 2003; Fernandez et al. 2006) helped to constrain the physics of the phenomenon and to specify the characteristics of the suspected FEBs, which number may be as large as several hundreds per year. The large number of available data enabled a statistical approach of these events and of their characteristics. It rapidly turned out that the infall of FEBs towards beta Pictoris from the disk was not isotropic. This raised the issue of the dynamical origin of this phenomenon. In the late 1990's, Beust & Morbidelli (1996, 2000) proposed that FEBs could originate from 4:1 and 3:1 mean-motion resonances with a hypothetical giant planet, and fall towards the star thanks to a drastic increase of their eccentricities thanks to the resonances. Exhaustive dynamical simulations led to propose that the suspected planet could orbit the star at ~10 AU one a moderately eccentric orbit (e~0.05-0.1). Further investigations (Beust & Valiron 2007) also depicted the possible role of FEBs in the generation of detected gas at high latitude above the disk mid-plane (Brandeker et al. 2004). The imaged planet beta Pictoris b shares many common characteristics with the FEB generating planet suspected 15 years ago. It is then tempting to merge them. A considerable effort has been done in recent years to refine the orbital determination of beta Pictoris b (Chauvin et al. 2012), and to improve the statistical analysis of the available FEB data. It has been recently shown (Kiefer et al. 2014) that two separate families of FEBs are probably present, perhaps originating from distinct resonances with the planet. A few other stars have been shown to present FEB-like spectral events that have been claimed to originate from the same phenomenon. Although none is as convincing as Beta Pictoris itself, some of them are possible analogs. The dynamical phenomenon triggering the FEB phenomenon as rather generic. A similar phenomenon is suspected to have occurred in the early ages of the Solar System, giving birth to the so-called Kirkwood gaps. But the detectability of the phenemenon from the Earth is a subtle combination of suitable stellar type, viewing geometry and age range.

Recommended treatment strategies for patients with excessive daytime sleepiness.

PubMed

Rosenberg, Russell P

2015-10-01

Excessive daytime sleepiness (EDS) is a common and bothersome phenomenon. It can be associated with insufficient sleep syndrome, narcolepsy, idiopathic hypersomnia, obstructive sleep apnea, shift work disorder, Kleine-Levin syndrome, or Parkinson's disease. Once the underlying cause of the excessive sleepiness is determined, clinicians must select the most appropriate behavioral and pharmacologic interventions to reduce daytime sleepiness, alleviate other symptoms, improve functioning, and ensure the safety of patients and those around them. Patient history, adverse effects, and efficacy in specific conditions should be considered in pharmacologic treatment options for patients with EDS. © Copyright 2015 Physicians Postgraduate Press, Inc.

Hatch cover

NASA Technical Reports Server (NTRS)

Allton, Charles S. (Inventor); Okane, James H. (Inventor)

1989-01-01

This invention relates to a hatch and more particularly to a hatch for a space vehicle where the hatch has a low volume sweep and can be easily manipulated from either side of the hatch. The hatch system includes an elliptical opening in a bulkhead and an elliptical hatch member. The hatch cover system includes an elliptical port opening in a housing and an elliptical cover member supported centrally by a rotational bearing for rotation about a rotational axis normal to the cover member and by pivot pins in a gimbal member for pivotal movement about axes perpendicular to the rotational axis. Arm members support the gimbal member pivotally by pivot members so that upon rotation and manipulation the cover member can be articulatedly moved from a closed position to the port opening to an out of the way position with a minimum of volume sweep by the cover member.

Walk and roll robot

NASA Technical Reports Server (NTRS)

Wilson, Andrew (Inventor); Punnoose, Andrew (Inventor); Strausser, Katherine (Inventor); Parikh, Neil (Inventor)

2011-01-01

A mobile robotic unit features a main body, a plurality of legs for supporting the main body on and moving the main body in forward and reverse directions about a base surface, and a drive assembly. According to an exemplary embodiment each leg includes a respective pivotal hip joint, a pivotal knee joint, and a wheeled foot adapted to roll along the base surface. Also according to an exemplary embodiments the drive assembly includes a motor operatively associated with the hip and knee joints and the wheeled foot for independently driving pivotal movement of the hip joint and the knee joint and rolling motion of the wheeled foot. The hip joint may include a ball-and-socket-type joint interconnecting top portion of the leg to the main body, such that the hip joint is adapted to pivot said leg in a direction transverse to a forward-and-reverse direction.

Dual resolution, vacuum compatible optical mount

DOE Office of Scientific and Technical Information (OSTI.GOV)

Halpin, John Michael

2011-10-04

An optical mount for an optical element includes a mounting plate, a lever arm pivot coupled to mounting plate, and an adjustment plate. The optical mount also includes a flexure pivot mechanically coupling the adjustment plate to the mounting plate and a lever arm. The optical mount further includes a first adjustment device extending from the adjustment plate to make contact with the lever arm at a first contact point. A projection of a line from the first contact point to a pivot point, measured along the lever arm, is a first predetermined distance. The optical mount additionally includes amore » second adjustment device extending from the adjustment plate to make contact with the lever arm at a second contact point. A projection of a line from the second contact point to the pivot point, measured along the lever arm, is a second predetermined distance greater than the first predetermined distance.« less

Modified rib pivot lateral thoracotomy: a case series.

PubMed

Appelgrein, C; Hosgood, G

2018-01-01

To describe a modified rib pivot thoracotomy and its clinical application in client-owned dogs and cats. Case series of 24 dogs and 1 cat requiring a thoracotomy. A lateral thoracic incision over the required thoracic segment was made. The latissimus dorsi muscle was reflected dorsally. The predetermined rib was identified and the periosteum overlying the rib was elevated circumferentially, avoiding the intercostal neurovascular structures. Holes were pre-placed above and below the proposed osteotomy site. The rib was osteotomised and pivoted cranially. The pleura was incised and the required intrathoracic procedure was then performed. The thoracic cavity was closed by pre-placement of a suture through the pre-placed holes within the osteotomised rib. The pleura and intercostal musculature were closed, avoiding the intercostal neurovascular structures. The rib was re-apposed and the lateral approach was closed. The cases included were reviewed for both the rib pivoted as per the procedure required and postoperative complications. The study group comprised 8 Staffordshire Bull Terriers, 2 Poodles, 2 German Shepherd Dogs, 1 each of Basset Hound, Rhodesian Ridgeback, Golden Retriever, Australian Shepherd, Vizsla, Bull Mastiff, Schnauzer, Jack Russell Terrier, Bulldog, Deerhound, Labrador Retriever and Australian Terrier, and 1 cat. A modified rib pivot thoracotomy was performed for lung lobectomy (n = 11), oesophagectomy (7), subtotal pericardectomy (5), patent ductus arteriosus ligation (1) and thoracic duct ligation (1). Follow-up ranged from 2 to 40 weeks postoperatively. Postoperative complications included seroma formation in two dogs. A modified rib pivot thoracotomy should be considered as an alternative lateral thoracic approach with good exposure, minimal complications and low morbidity. © 2018 Australian Veterinary Association.

How well do Radiologic Assessments of Truncal and Shoulder Balance Correlate With Cosmetic Assessment Indices in Lenke 1C Adolescent Idiopathic Scoliosis?

PubMed

Sharma, Shallu; Andersen, Thomas; Wu, Chunsen; Sun, Haolin; Wang, Yu; Hansen, Ebbe S; Bünger, Cody E

2016-10-01

A correlation study. The primary objective was to determine the correlation between radiologic and cosmetic indices of trunk and shoulder balance before and after scoliosis surgery in Lenke 1C adolescent idiopathic scoliosis and to determine whether postoperative trunk shift is affiliated with worsening of the patients' cosmesis. Achieving a symmetrical appearance with truncal and shoulder balance is of prime importance to adolescent idiopathic scoliosis patients and their surgeons. However, surgeons prefer radiographic indices rather than measures of patients' clinical appearance. If radiographic indices are to be considered accurate depictions of the patient's cosmesis, radiologic and cosmetic indices must necessarily exhibit high association. Radiographic and cosmetic indices of trunk and shoulder balance, along with posterior trunk symmetry index, were measured preoperatively and 3 months postoperatively in 33 Lenke 1C scoliosis patients. Pearson correlation analysis was performed. Paired t test was used to determine significant changes in radiographic and cosmetic indices after surgery. Independent-sample t test was used for all intergroup analyses in trunk shift and no-trunk-shift groups. Correlation coefficients between radiologic and cosmetic indices ranged between -0.63 and 0.70 with thoracic apical vertebra-central sacral vertical line (AV-CSVL) distance and first rib angle showing consistent correlations with cosmetic trunk and cosmetic shoulder balance indices. Trunk shift, a postoperative iatrogenic phenomenon, was seen in 19 (58%) patients. These patients had higher preoperative thoracic AV-CSVL translation, thoracic apical vertebra-first thoracic vertebra (AV-T1) translation, thoracic deformity correction rate, AV-T1 correction rates, and shorter fusions compared with the no-trunk-shift group. Posterior trunk symmetry index worsened in trunk shift group and improved significantly (-7.94 vs. 16.53) in no-trunk-shift group. Significant association (P=0.004) was seen between radiographic and cosmetic trunk shift. Radiographic indices can only minisculely (r≤0.7) reflect cosmetic deformity in Lenke 1C scoliosis, which emphasizes not only the vulnerability of overreliance on radiographic indices but also the vital importance of clinical cosmetic evaluations. In particular, cosmetic shoulder height and angle are not represented by radiographic indices. However, radiograph trunk shift was significantly associated with cosmetic trunk shift in cosmetic pictures.

A Stratified Acoustic Model Accounting for Phase Shifts for Underwater Acoustic Networks

PubMed Central

Wang, Ping; Zhang, Lin; Li, Victor O. K.

2013-01-01

Accurate acoustic channel models are critical for the study of underwater acoustic networks. Existing models include physics-based models and empirical approximation models. The former enjoy good accuracy, but incur heavy computational load, rendering them impractical in large networks. On the other hand, the latter are computationally inexpensive but inaccurate since they do not account for the complex effects of boundary reflection losses, the multi-path phenomenon and ray bending in the stratified ocean medium. In this paper, we propose a Stratified Acoustic Model (SAM) based on frequency-independent geometrical ray tracing, accounting for each ray's phase shift during the propagation. It is a feasible channel model for large scale underwater acoustic network simulation, allowing us to predict the transmission loss with much lower computational complexity than the traditional physics-based models. The accuracy of the model is validated via comparisons with the experimental measurements in two different oceans. Satisfactory agreements with the measurements and with other computationally intensive classical physics-based models are demonstrated. PMID:23669708

Microwave imaging of spinning object using orbital angular momentum

NASA Astrophysics Data System (ADS)

Liu, Kang; Li, Xiang; Gao, Yue; Wang, Hongqiang; Cheng, Yongqiang

2017-09-01

The linear Doppler shift used for the detection of a spinning object becomes significantly weakened when the line of sight (LOS) is perpendicular to the object, which will result in the failure of detection. In this paper, a new detection and imaging technique for spinning objects is developed. The rotational Doppler phenomenon is observed by using the microwave carrying orbital angular momentum (OAM). To converge the radiation energy on the area where objects might exist, the generation method of OAM beams is proposed based on the frequency diversity principle, and the imaging model is derived accordingly. The detection method of the rotational Doppler shift and the imaging approach of the azimuthal profiles are proposed, which are verified by proof-of-concept experiments. Simulation and experimental results demonstrate that OAM beams can still be used to obtain the azimuthal profiles of spinning objects even when the LOS is perpendicular to the object. This work remedies the insufficiency in existing microwave sensing technology and offers a new solution to the object identification problem.

Gouy phase for relativistic quantum particles

NASA Astrophysics Data System (ADS)

Ducharme, R.; da Paz, I. G.

2015-08-01

Exact Hermite-Gaussian solutions to the Klein-Gordon equation for particle beams are obtained here that depend on the 4-position of the beam waist. These are Bateman-Hillion solutions that are shown to include Gouy phase and preserve their forms under Lorentz transformations. As the wave function contains two time coordinates, the particle current must be interpreted in a constraint space to reduce the number of independent coordinates. The form of the constraint space is not certain except in the nonrelativistic limit, but a trial form is proposed, enabling the observable properties of the beam to be calculated for future comparison to experiment. These results can be relevant in the theoretical development of singular electron optics since it was shown that the Gouy phase is crucial in this field as well as to investigate a possible Gouy phase effect in Zitterbewegung phenomenon of spin-zero particles. Additionally, the traditional argument that beam solutions belong to a complex shifted spacetime is shown to necessitate a corresponding Born reciprocal shift in 4-momentum space.

Welding Experiments of Aluminum Alloy by Space GHTA Welding at ISS Orbital Pressure

NASA Astrophysics Data System (ADS)

Suita, Yoshikazu; Takai, Daisuke; Sugiyama, Satoshi; Terajima, Noboru; Tsukuda, Yoshiyuki; Fujisawa, Shoichiro; Imagawa, Kichiro

As a feasible welding method in space, the authors previously proposed the space GHTA (Gas Hollow Tungsten Arc) welding process. However, space GHTA welding with a high-frequency device for arc start may cause electromagnetic noise problems for the computer equipment placed on the ISS (International Space Station). Therefore, in this report, welding experiments of space GHTA welding using aluminum alloy with a high-voltage DC device for arc start were carried out at the ISS orbital pressure, 10-5 Pa. It is clear from the experiments using a high-voltage DC device in a high-vacuum condition, that there is a shifting phenomenon in which the spark discharge shifts to either a glow discharge or an arc discharge when starting the arc. Welding projects in space need an arc discharge, so we investigated the effects of welding parameters on the arc formation ratio. As a result, space GHTA welding with a high-voltage DC device can be used for arc start when welding at the ISS orbital pressure.

Relationship between Mass Loading and Frequency Temperature Characteristics of AT-Cut Quartz Resonators

NASA Astrophysics Data System (ADS)

Gong, Xun; Sekimoto, Hitoshi; Goka, Shigeyoshi; Watanabe, Yasuaki

2003-07-01

Past experiments indicated that the mass loading (R) results in a shift of the apparent orientation angle of the quartz plate and this shift is proportional to the thickness of the metal film and the difference between the thermal expansion coefficients (α) of the electrode and the substrate. In this study, first we make a new model that includes the anisotropy of quartz based on the model of EerNisse [Proc. 29th Annu. Freq. Control Symp., 1975, p. 1] to obtain the thermally induced strain bias. Then, we deduce a simple relationship for the thickness shear vibrations from Lee and Tang’s [IEEE Trans. Ultrason. Ferroelect. & Freq. Control 34 (1987) 659] theory of small-magnitude vibration superposing on the bias strain field. A new method which can enable a strict analysis of the phenomenon is thus developed. The simulation of several kinds of metal films is performed. The results agree well with the above-mentioned experimental results.

Spectro-spatial analysis of wave packet propagation in nonlinear acoustic metamaterials

NASA Astrophysics Data System (ADS)

Zhou, W. J.; Li, X. P.; Wang, Y. S.; Chen, W. Q.; Huang, G. L.

2018-01-01

The objective of this work is to analyze wave packet propagation in weakly nonlinear acoustic metamaterials and reveal the interior nonlinear wave mechanism through spectro-spatial analysis. The spectro-spatial analysis is based on full-scale transient analysis of the finite system, by which dispersion curves are generated from the transmitted waves and also verified by the perturbation method (the L-P method). We found that the spectro-spatial analysis can provide detailed information about the solitary wave in short-wavelength region which cannot be captured by the L-P method. It is also found that the optical wave modes in the nonlinear metamaterial are sensitive to the parameters of the nonlinear constitutive relation. Specifically, a significant frequency shift phenomenon is found in the middle-wavelength region of the optical wave branch, which makes this frequency region behave like a band gap for transient waves. This special frequency shift is then used to design a direction-biased waveguide device, and its efficiency is shown by numerical simulations.

Origin of oxygen in sulfate during pyrite oxidation with water and dissolved oxygen: an in situ horizontal attenuated total reflectance infrared spectroscopy isotope study.

PubMed

Usher, Courtney R; Cleveland, Curtis A; Strongin, Daniel R; Schoonen, Martin A

2004-11-01

FeS2 (pyrite) is known to react with water and dissolved molecular oxygen to form sulfate and iron oxyhydroxides. This process plays a large role in the environmentally damaging phenomenon known as acid mine drainage. An outstanding scientific issue has been whether the oxygen in the sulfate and oxyhydroxide product was derived from water and/or dissolved oxygen. By monitoring the reaction in situ with horizontal attenuated total reflectance infrared spectroscopy, it was found that when using 18O isotopically substituted water, the majority of the infrared absorbance due to sulfate product red-shifted approximately 70 cm(-1) relative to the absorbance of sulfate using H(2)16O as a reactant. Bands corresponding to the iron oxyhydroxide product did not shift. These results indicate water as the primary source of oxygen in the sulfate product, while the oxygen atoms in the iron oxyhydroxide product are obtained from dissolved molecular oxygen.

A stratified acoustic model accounting for phase shifts for underwater acoustic networks.

PubMed

Wang, Ping; Zhang, Lin; Li, Victor O K

2013-05-13

Accurate acoustic channel models are critical for the study of underwater acoustic networks. Existing models include physics-based models and empirical approximation models. The former enjoy good accuracy, but incur heavy computational load, rendering them impractical in large networks. On the other hand, the latter are computationally inexpensive but inaccurate since they do not account for the complex effects of boundary reflection losses, the multi-path phenomenon and ray bending in the stratified ocean medium. In this paper, we propose a Stratified Acoustic Model (SAM) based on frequency-independent geometrical ray tracing, accounting for each ray's phase shift during the propagation. It is a feasible channel model for large scale underwater acoustic network simulation, allowing us to predict the transmission loss with much lower computational complexity than the traditional physics-based models. The accuracy of the model is validated via comparisons with the experimental measurements in two different oceans. Satisfactory agreements with the measurements and with other computationally intensive classical physics-based models are demonstrated.

Spontaneous supercurrent and φ0 phase shift parallel to magnetized topological insulator interfaces

NASA Astrophysics Data System (ADS)

Alidoust, Mohammad; Hamzehpour, Hossein

2017-10-01

Employing a Keldysh-Eilenberger technique, we theoretically study the generation of a spontaneous supercurrent and the appearance of the φ0 phase shift parallel to uniformly in-plane magnetized superconducting interfaces made of the surface states of a three-dimensional topological insulator. We consider two weakly coupled uniformly magnetized superconducting surfaces where a macroscopic phase difference between the s -wave superconductors can be controlled externally. We find that, depending on the magnetization strength and orientation on each side, a spontaneous supercurrent due to the φ0 states flows parallel to the interface at the nanojunction location. Our calculations demonstrate that nonsinusoidal phase relations of current components with opposite directions result in maximal spontaneous supercurrent at phase differences close to π . We also study the Andreev subgap channels at the interface and show that the spin-momentum locking phenomenon in the surface states can be uncovered through density of states studies. We finally discuss realistic experimental implications of our findings.

A Practical Approach to Tumor Heterogeneity in Clinical Research and Diagnostics.

PubMed

Stanta, Giorgio; Bonin, Serena

2018-01-01

This Pathobiology issue tries to better define the complex phenomenon of intratumor heterogeneity (ITH), mostly from a practical point of view. This topic has been chosen because ITH is a central issue in tumor development and has to be investigated directly in patient tissue and immediately applied in the treatment of the presenting patient. Different types of ITH should be considered: clonal genetic and epigenetic evolution, morphological heterogeneity, and tumor sampling, heterogeneity resulting from microenvironmental autocrine and paracrine interaction, and stochastic plasticity related to different functional cell efficiencies. For a higher level of reproducibility in clinical research and diagnostics, it is necessary to establish standardized analytical methods, including microdissection. In situ techniques can be pivotal to explore tumor microenvironment and can be improved with associated digital analysis. Liquid biopsies for plasma DNA analysis are at present the best method to study recurrent tumors with treatment adaptation, and widespread clinical use could be beneficial. The different types of tumor genomic instabilities could have pragmatic applications to rank ITH for clinical applications: treatment approaches differ in patients with a high nucleotide mutation rate and patients with high copy number alterations. © 2017 S. Karger AG, Basel.

The amyloid interactome: Exploring protein aggregation

PubMed Central

Mastrokalou, Chara V.; Hamodrakas, Stavros J.

2017-01-01

Protein-protein interactions are the quintessence of physiological activities, but also participate in pathological conditions. Amyloid formation, an abnormal protein-protein interaction process, is a widespread phenomenon in divergent proteins and peptides, resulting in a variety of aggregation disorders. The complexity of the mechanisms underlying amyloid formation/amyloidogenicity is a matter of great scientific interest, since their revelation will provide important insight on principles governing protein misfolding, self-assembly and aggregation. The implication of more than one protein in the progression of different aggregation disorders, together with the cited synergistic occurrence between amyloidogenic proteins, highlights the necessity for a more universal approach, during the study of these proteins. In an attempt to address this pivotal need we constructed and analyzed the human amyloid interactome, a protein-protein interaction network of amyloidogenic proteins and their experimentally verified interactors. This network assembled known interconnections between well-characterized amyloidogenic proteins and proteins related to amyloid fibril formation. The consecutive extended computational analysis revealed significant topological characteristics and unraveled the functional roles of all constituent elements. This study introduces a detailed protein map of amyloidogenicity that will aid immensely towards separate intervention strategies, specifically targeting sub-networks of significant nodes, in an attempt to design possible novel therapeutics for aggregation disorders. PMID:28249044

In our own image? Emotional and neural processing differences when observing human–human vs human–robot interactions

PubMed Central

Wang, Yin

2015-01-01

Notwithstanding the significant role that human–robot interactions (HRI) will play in the near future, limited research has explored the neural correlates of feeling eerie in response to social robots. To address this empirical lacuna, the current investigation examined brain activity using functional magnetic resonance imaging while a group of participants (n = 26) viewed a series of human–human interactions (HHI) and HRI. Although brain sites constituting the mentalizing network were found to respond to both types of interactions, systematic neural variation across sites signaled diverging social-cognitive strategies during HHI and HRI processing. Specifically, HHI elicited increased activity in the left temporal–parietal junction indicative of situation-specific mental state attributions, whereas HRI recruited the precuneus and the ventromedial prefrontal cortex (VMPFC) suggestive of script-based social reasoning. Activity in the VMPFC also tracked feelings of eeriness towards HRI in a parametric manner, revealing a potential neural correlate for a phenomenon known as the uncanny valley. By demonstrating how understanding social interactions depends on the kind of agents involved, this study highlights pivotal sub-routes of impression formation and identifies prominent challenges in the use of humanoid robots. PMID:25911418

Modeling continuum of epithelial mesenchymal transition plasticity.

PubMed

Mandal, Mousumi; Ghosh, Biswajoy; Anura, Anji; Mitra, Pabitra; Pathak, Tanmaya; Chatterjee, Jyotirmoy

2016-02-01

Living systems respond to ambient pathophysiological changes by altering their phenotype, a phenomenon called 'phenotypic plasticity'. This program contains information about adaptive biological dynamism. Epithelial-mesenchymal transition (EMT) is one such process found to be crucial in development, wound healing, and cancer wherein the epithelial cells with restricted migratory potential develop motile functions by acquiring mesenchymal characteristics. In the present study, phase contrast microscopy images of EMT induced HaCaT cells were acquired at 24 h intervals for 96 h. The expression study of relevant pivotal molecules viz. F-actin, vimentin, fibronectin and N-cadherin was carried out to confirm the EMT process. Cells were intuitively categorized into five distinct morphological phenotypes. A population of 500 cells for each temporal point was selected to quantify their frequency of occurrence. The plastic interplay of cell phenotypes from the observations was described as a Markovian process. A model was formulated empirically using simple linear algebra, to depict the possible mechanisms of cellular transformation among the five phenotypes. This work employed qualitative, semi-quantitative and quantitative tools towards illustration and establishment of the EMT continuum. Thus, it provides a newer perspective to understand the embedded plasticity across the EMT spectrum.

Torque Compensator for Mirror Mountings

NASA Technical Reports Server (NTRS)

Howe, S. D.

1983-01-01

Device nulls flexural distributions of pivotal torques. Magnetic compensator for flexing pivot torque consists of opposing fixed and movable magnet bars. Magnetic torque varies nonlinearly as function of angle of tilt of movable bar. Positions of fixed magnets changed to improve magnetic torque linearity.

Compound floating pivot micromechanisms

DOEpatents

Garcia, Ernest J.

2001-04-24

A new class of tilting micromechanical mechanisms have been developed. These new mechanisms use compound floating pivot structures to attain far greater tilt angles than are practical using other micromechanical techniques. The new mechanisms are also capable of bi-directional tilt about multiple axes.

Investigation of delayed cracking in pivot steel box girders.

DOT National Transportation Integrated Search

1997-01-01

This report describes the results of an investigation to find the cause of the delayed cracking in the welds of the fracturecritical steel pivot box girders fabricated for the George P. Coleman Bridge. Through the use of different nondestructive meth...

Is set shifting really impaired in trait anxiety? Only when switching away from an effortfully established task set.

PubMed

Gustavson, Daniel E; Altamirano, Lee J; Johnson, Daniel P; Whisman, Mark A; Miyake, Akira

2017-02-01

The current study investigated whether trait anxiety was systematically related to task-set shifting performance, using a task-switching paradigm in which 1 task was more attentionally demanding than the other. Specifically, taking advantage of a well-established phenomenon known as asymmetric switch costs, we tested the hypothesis that the association between trait anxiety and task-set shifting is most clearly observed when individuals must switch away from a more attentionally demanding task for which it was necessary to effortfully establish an appropriate task set. Ninety-one young adults completed an asymmetric switching task and trait-level mood questionnaires. Results indicated that higher levels of trait anxiety were systematically associated with greater asymmetry in reaction time (RT) switch costs. Specifically, the RT costs for switching from the more attentionally demanding task to the less demanding task were significantly greater with higher levels of trait anxiety, whereas the RT costs for switching in the opposite direction were not significantly associated with trait anxiety levels. Further analyses indicated that these associations were not attributable to comorbid dysphoria or worry. These results suggest that levels of trait anxiety may not be related to general set-shifting ability per se, but, rather, that anxiety-specific effects may primarily be restricted to when one must efficiently switch away from (or let go of) an effortfully established task set. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Suppression of contrast-related artefacts in phase-measuring structured light techniques

NASA Astrophysics Data System (ADS)

Burke, Jan; Zhong, Liang

2017-06-01

Optical metrology using phase measurements has benefited significantly from the introduction of phase-shifting methods, first in interferometry, then also in fringe projection and fringe reflection. As opposed to interferometry, the latter two techniques generally use a spatiotemporal phase-shifting approach: A sequence of fringe patterns with varying spacing is used, and a phase map of each is generated by temporal phase shifting, to allow unique assignments of projector or screen pixels to camera pixels. One ubiquitous problem with phase-shifting structured-light techniques is that phase artefacts appear near regions of the image where the modulation amplitude of the projected or reflected fringes changes abruptly, e.g. near dirt/dust particles on the surface in deflectometry or bright-dark object colour transitions in fringe projection. Near the bright-dark boundaries, responses in the phase maps appear that are not plausible as actual surface features. The phenomenon has been known for a long time but is usually ignored because it does not compromise the overall reliability of results. In deflectometry, however, often the objective is to find and classify small defects, and of course it is then important to distinguish between bogus phase responses caused by fringe modulation changes, and actual surface defects. We present, for what we believe is the first time, an analytical derivation of the error terms, study the parameters influencing the phase artefacts (in particular the fringe period), and suggest some simple algorithms to minimise them.

Differential effects of removing the glucose or saccharin components of a glucose-saccharin mixture in a successive negative contrast paradigm.

PubMed

Mitchell, Colin P; Flaherty, Charles F

2005-03-31

When rats experience an unexpected decrease in reward value, e.g., from 32% sucrose to 4% sucrose, consummatory behavior abruptly decreases to a level below control subjects that only experience the lesser reward, a phenomenon known as Successive Negative Contrast (SNC). In food deprived rats experiencing downshifts in sucrose concentration, SNC dissipates in 3-4 days, as consummatory behavior in shifted rats recovers to the level of unshifted controls. In Experiment 1 food deprived rats that were given 5 min daily access to a 2% glucose-0.15% saccharin mixture, and subsequently shifted to 2% glucose alone, displayed a dramatic SNC effect relative to rats that only received 2% glucose. This SNC effect was primarily manifested as a decrease in the number of consummatory bursts initiated. Interestingly, intake failed to recover to control levels during eight daily postshift sessions. However, in Experiment 2 subjects that were shifted from the same glucose-saccharin mixture to 0.15% saccharin alone failed to show SNC rather, intake fell to the level of control animals which only received 0.15% saccharin. The data from Experiment 1, in conjunction with previous studies utilizing non-deprived rats, quinine adulteration, or shifts from sucrose to saccharin, show that reductions in taste value can produce contrast effects, but suggest that a threshold caloric value is necessary for recovery. The data from Experiment 2 may suggest that saccharin and glucose do not contribute equally to the enhanced palatability of the mixture.

Duffing revisited: phase-shift control and internal resonance in self-sustained oscillators

NASA Astrophysics Data System (ADS)

Arroyo, Sebastián I.; Zanette, Damián H.

2016-01-01

We address two aspects of the dynamics of the forced Duffing oscillator which are relevant to the technology of micromechanical devices and, at the same time, have intrinsic significance to the field of nonlinear oscillating systems. First, we study the stability of periodic motion when the phase shift between the external force and the oscillation is controlled - contrary to the standard case, where the control parameter is the frequency of the force. Phase-shift control is the operational configuration under which self-sustained oscillators - and, in particular, micromechanical oscillators - provide a frequency reference useful for time keeping. We show that, contrary to the standard forced Duffing oscillator, under phase-shift control oscillations are stable over the whole resonance curve, and provide analytical approximate expressions for the time dependence of the oscillation amplitude and frequency during transients. Second, we analyze a model for the internal resonance between the main Duffing oscillation mode and a higher-harmonic mode of a vibrating solid bar clamped at its two ends. We focus on the stabilization of the oscillation frequency when the resonance takes place, and present preliminary experimental results that illustrate the phenomenon. This synchronization process has been proposed to counteract the undesirable frequency-amplitude interdependence in nonlinear time-keeping micromechanical devices. Supplementary material in the form of one pdf file and one gif file available from the Journal web page at http://dx.doi.org/10.1140/epjb/e2015-60517-3

Rapidly shifting environmental baselines among fishers of the Gulf of California

PubMed Central

Sáenz-Arroyo, Andrea; Roberts, Callum M; Torre, Jorge; Cariño-Olvera, Micheline; Enríquez-Andrade, Roberto R

2005-01-01

Shifting environmental baselines are inter-generational changes in perception of the state of the environment. As one generation replaces another, people's perceptions of what is natural change even to the extent that they no longer believe historical anecdotes of past abundance or size of species. Although widely accepted, this phenomenon has yet to be quantitatively tested. Here we survey three generations of fishers from Mexico's Gulf of California (N=108), where fish populations have declined steeply over the last 60 years, to investigate how far and fast their environmental baselines are shifting. Compared to young fishers, old fishers named five times as many species and four times as many fishing sites as once being abundant/productive but now depleted (Kruskal–Wallis tests, both p<0.001) with no evidence of a slowdown in rates of loss experienced by younger compared to older generations (Kruskal–Wallis test, n.s. in both cases). Old fishers caught up to 25 times as many Gulf grouper Mycteroperca jordani as young fishers on their best ever fishing day (regression r2=0.62, p<0.001). Despite times of plentiful large fish still being within living memory, few young fishers appreciated that large species had ever been common or nearshore sites productive. Such rapid shifts in perception of what is natural help explain why society is tolerant of the creeping loss of biodiversity. They imply a large educational hurdle in efforts to reset expectations and targets for conservation. PMID:16191603

Rebirth of the Bashful ballerina

NASA Astrophysics Data System (ADS)

Mursula, Kalevi; Virtanen, Ilpo

2016-04-01

Heliospheric current sheet (HCS) is the continuation of the coronal magnetic equator into space, dividing the heliospheric magnetic field (HMF) into two sectors. Because of its wavy structure, the HCS is also called the ballerina skirt. Several recent studies have proven that the HCS is southward shifted during about three years in the solar declining to minimum phase. This persistent phenomenon, now called the Bashful ballerina, has been seen in geomagnetic indices since 1930s, OMNI data since 1960s, WSO data since mid-1970s and in Ulysses probe measurements during the fast latitude scans in 1994-1995 and 2007. Here we study the long-term evolution of photospheric and coronal magnetic fields and the heliospheric current sheet since 1975 using synoptic maps from six observatories (WSO, MWO, Kitt Peak, SOLIS, SOHO/MDI and SDO/HMI). All data sets depict a fairly similar long-term evolution of magnetic fields and the heliospheric current sheet, and agree on the southward shift of the heliospheric current sheet during all the five included cycles. We show that during solar cycles 20 -- 22, the southward shift of the HCS is due to the axial quadrupole term, reflecting the stronger magnetic field intensity at the southern pole during these times. During cycle 23 the asymmetry is less persistent and due to higher harmonics than the quadrupole term. Currently, in the early declining phase of cycle 24, the HCS is also shifted southward and is, again, due to the axial quadrupole, repeating the pattern of most previous cycles.

Bashful ballerina: Multi-instrument verification and recent behaviour

NASA Astrophysics Data System (ADS)

Mursula, Kalevi; Virtanen, Ilpo

2016-07-01

Heliospheric current sheet (HCS) is the continuation of the coronal magnetic equator into space, dividing the heliospheric magnetic field (HMF) into two sectors. Because of its wavy structure, the HCS is also called the ballerina skirt. Several recent studies have proven that the HCS is southward shifted during about three years in the solar declining to minimum phase. This persistent phenomenon, now called the Bashful ballerina, has been seen in geomagnetic indices since 1930s, OMNI data since 1960s, WSO data since mid-1970s and in Ulysses probe measurements during the fast latitude scans in 1994-1995 and 2007. Here we study the long-term evolution of photospheric and coronal magnetic fields and the heliospheric current sheet since 1975 using synoptic maps from six observatories (WSO, MWO, Kitt Peak, SOLIS, SOHO/MDI and SDO/HMI). All data sets depict a fairly similar long-term evolution of magnetic fields and the heliospheric current sheet, and agree on the southward shift of the heliospheric current sheet during all the five included cycles. We show that during solar cycles 20 -- 22, the southward shift of the HCS is due to the axial quadrupole term, reflecting the stronger magnetic field intensity at the southern pole during these times. During cycle 23 the asymmetry is less persistent and due to higher harmonics than the quadrupole term. Currently, in the early declining phase of cycle 24, the HCS is also shifted southward and is, again, due to the axial quadrupole, repeating the pattern of most previous cycles.

New fundamental parameters for attitude representation

NASA Astrophysics Data System (ADS)

Patera, Russell P.

2017-08-01

A new attitude parameter set is developed to clarify the geometry of combining finite rotations in a rotational sequence and in combining infinitesimal angular increments generated by angular rate. The resulting parameter set of six Pivot Parameters represents a rotation as a great circle arc on a unit sphere that can be located at any clocking location in the rotation plane. Two rotations are combined by linking their arcs at either of the two intersection points of the respective rotation planes. In a similar fashion, linking rotational increments produced by angular rate is used to derive the associated kinematical equations, which are linear and have no singularities. Included in this paper is the derivation of twelve Pivot Parameter elements that represent all twelve Euler Angle sequences, which enables efficient conversions between Pivot Parameters and any Euler Angle sequence. Applications of this new parameter set include the derivation of quaternions and the quaternion composition rule, as well as, the derivation of the analytical solution to time dependent coning motion. The relationships between Pivot Parameters and traditional parameter sets are included in this work. Pivot Parameters are well suited for a variety of aerospace applications due to their effective composition rule, singularity free kinematic equations, efficient conversion to and from Euler Angle sequences and clarity of their geometrical foundation.

The effects of target distance on pivot hip, trunk, pelvis, and kicking leg kinematics in Taekwondo roundhouse kicks.

PubMed

Kim, Jae-Woong; Kwon, Moon-Seok; Yenuga, Sree Sushma; Kwon, Young-Hoooo

2010-06-01

The study purpose was to investigate the effects of target distance on pivot hip, trunk, pelvis, and kicking leg movements in Taekwondo roundhouse kick. Twelve male black-belt holders executed roundhouse kicks for three target distances (Normal, Short, and Long). Linear displacements of the pivot hip and orientation angles of the pelvis, trunk, right thigh, and right shank were obtained through a three-dimensional video motion analysis. Select displacements, distances, peak orientation angles, and angle ranges were compared among the conditions using one-way repeated measure ANOVA (p < 0.05). Several orientation angle variables (posterior tilt range, peak right-tilted position, peak right-rotated position, peak left-rotated position, and left rotation range of the pelvis; peak hyperextended position and peak right-flexed position of the trunk; peak flexed position, flexion range and peak internal-rotated position of the hip) as well as the linear displacements of the pivot hip and the reach significantly changed in response to different target distances. It was concluded that the adjustment to different target distances was mainly accomplished through the pivot hip displacements, hip flexion, and pelvis left rotation. Target distance mainly affected the reach control function of the pelvis and the linear balance function of the trunk.

Tibial and Femoral Tunnel Changes After ACL Reconstruction: A Prospective 2-Year Longitudinal MRI Study.

PubMed

Weber, Alexander E; Delos, Demetris; Oltean, Hanna N; Vadasdi, Katherine; Cavanaugh, John; Potter, Hollis G; Rodeo, Scott A

2015-05-01

Tunnel widening after anterior cruciate ligament reconstruction (ACL-R) is a well-accepted and frequent phenomenon, yet little is known regarding its origin or natural history. To prospectively evaluate the cross-sectional area (CSA) changes in tibial and femoral bone tunnels after ACL-R with serial MRI. Case series; Level of evidence, 4. Patients underwent arthroscopic ACL-R with the same surgeon, surgical technique, and rehabilitation protocol. Each patient underwent preoperative dual-energy x-ray absorptiometry and clinical evaluation, as well as postoperative time zero MRI followed by subsequent MRI and clinical examination, including functional and subjective outcome tests, at 6, 12, 24, 52, and 104 weeks. Tibial and femoral tunnel CSA was measured on each MRI at tunnel aperture (ttA and ftA), midsection (ttM and ftM), and exit (ttE and ftE). Logistic regression modeling was used to examine the predictive value of demographic data and preoperative bone quality (as measured by dual-energy x-ray absorptiometry) on functional outcome scores, manual and instrumented laxity measurements, and changes in tunnel area over time. Eighteen patients (including 12 men), mean age 35.5±8.7 years, underwent ACL-R. There was significant tunnel expansion at ttA and ftA sites 6 weeks postoperatively (P=.024 and .0045, respectively). Expansion continued for 24 weeks, with progressive tunnel narrowing thereafter. Average ttA CSA was significantly larger than ftA CSA at all times. The ttM significantly expanded after 6 weeks (P=.06); continued expansion to week 12 was followed by 21 months of reduction in tunnel diameter. The ftM and both ttE and ftE sites decreased in CSA over the 2 years. Median Lysholm and International Knee Documentation Committee scores significantly improved at final follow-up (P=.0083 and <.0001, respectively), and patients returned to preoperative activity levels. Pivot shift significantly decreased (P<.0001). Younger age (<30 years), male sex, and delayed ACL-R (>1 year from time of injury) predicted increased tunnel widening and accelerated expansion in CSA (P<.005). Tunnel expansion after ACL-R occurs early and primarily at the tunnel apertures. Expansion may not affect clinical outcome. Younger age, male sex, and delay from injury to ACL-R may be potential risks for enlargement. © 2015 The Author(s).

Interferometric characterization of the structured polarized light beam produced by the conical refraction phenomenon.

PubMed

Peinado, Alba; Turpin, Alex; Iemmi, Claudio; Márquez, Andrés; Kalkandjiev, Todor K; Mompart, Jordi; Campos, Juan

2015-07-13

The interest on the conical refraction (CR) phenomenon in biaxial crystals has revived in the last years due to its prospective for generating structured polarized light beams, i.e. vector beams. While the intensity and the polarization structure of the CR beams are well known, an accurate experimental study of their phase structure has not been yet carried out. We investigate the phase structure of the CR rings by means of a Mach-Zehnder interferometer while applying the phase-shifting interferometric technique to measure the phase at the focal plane. In general the two beams interfering correspond to different states of polarization (SOP) which locally vary. To distinguish if there is an additional phase added to the geometrical one we have derived the appropriate theoretical expressions using the Jones matrix formalism. We demonstrate that the phase of the CR rings is equivalent to that one introduced by an azimuthally segmented polarizer with CR-like polarization distribution. Additionally, we obtain direct evidence that the Poggendorff dark ring is an annular singularity, with a π phase change between the inner and outer bright rings.

Inhibition of quantum size effects from surface dangling bonds: The first principles study on different morphology SiC nanowires

NASA Astrophysics Data System (ADS)

Li, Yan-Jing; Li, Shu-Long; Gong, Pei; Li, Ya-Lin; Fang, Xiao-Yong; Jia, Ya-Hui; Cao, Mao-Sheng

2018-06-01

In recent years, we investigated the structure and photoelectric properties of Silicon carbide nanowires (SiCNWs) with different morphologies and sizes by using the first-principle in density functional theory, and found a phenomenon that is opposite to quantum size effect, namely, the band gap of nanowires increases with the increase of the diameter. To reveal the nature of this phenomenon, we further carry out the passivation of SiCNWs. The results show that the hydrogenated SiCNWs are direct band gap semiconductors, and the band gap decreases with the diameter increasing, which indicates the dangling bonds of the SiCNWs suppress its quantum size effect. The optical properties of SiCNWs with different diameters before and after hydrogenated are compared, we found that these surface dangling bonds lead to spectral shift which is different with quantum size effect of SiCNWs. These results have potential scientific value to deepen the understanding of the photoelectric properties of SiCNWs and to promote the development of optoelectronic devices.

Fair shares: a preliminary framework and case analyzing the ethics of offshoring.

PubMed

Gordon, Cameron; Zimmerman, Alan

2010-06-01

Much has been written about the offshoring phenomenon from an economic efficiency perspective. Most authors have attempted to measure the net economic effects of the strategy and many purport to show that "in the long run" that benefits will outweigh the costs. There is also a relatively large literature on implementation which describes the best way to manage the offshoring process. But what is the morality of offshoring? What is its "rightness" or "wrongness?" Little analysis of the ethics of offshoring has been completed thus far. This paper develops a preliminary framework for analyzing the ethics of offshoring and then applies this framework to basic case study of offshoring in the U.S. The paper following discusses the definition of offshoring; shifts to the basic philosophical grounding of the ethical concepts; develops a template for conducting an ethics analysis of offshoring; applies this template using basic data for offshoring in the United States; and conducts a preliminary ethical analysis of the phenomenon in that country, using a form of utilitarianism as an analytical baseline. The paper concludes with suggestions for further research.

Genesis and profanation of the other world: The interpretation of dreams.

PubMed

Drivet, Leandro

2017-12-01

This paper addresses Nietzsche's reflections on the phenomenon of dreams as a crucial precedent of Freud's Die Traumdeutung. The works of Nietzsche and Freud are scrutinized to establish and compare the most relevant aspects of their understanding of dreams. The philosophical impact of both accounts is assessed in terms of the transvaluation of religious and metaphysical values, which reveals three epistemological shifts: the replacement of Metaphysics by History/Genealogy (Nietzsche) and by Metapsychology (Freud), and the expansion of rationality beyond the limits of consciousness (Nietzsche and Freud). Both authors are shown to consider dreams as figurative expressions of a postponed desire - or, more specifically, as the imaginary fulfillment (compensation) and the evocation/awakening of desire. As captured by the phrase "Memento libidines", dreams are portrayed in both accounts as the guardians of sleep and desire. Finally, and in contrast with Assoun, a new interpretation of Thus Spoke Zarathustra is proposed, as an interpretation of the prophet's dreams reveals the presence of individual desire within the Nietzschean understanding of the phenomenon. Copyright © 2017 Institute of Psychoanalysis.

Paleomagnetic rotations and the Cenozoic tectonics of the Cascade Arc, Washington, Oregon, and California

USGS Publications Warehouse

Wells, R.E.

1990-01-01

Paleomagnetic results from Cenozoic (62-12 Ma) volcanic rocks of the Cascade Arc and adjacent areas indicate that moderate to large clockwise rotations are an important component of the tectonic history of the arc, Two mechanisms of rotation are suggested. The progressive increase in rotation toward the coast in arc and forearc rocks results from distributed dextral shear, which is likely driven by oblique subduction of oceanic plates to the west. Simple shear rotation is accommodated in the upper crust by strike-slip faulting. A progressive eastward shift of the arc volcanic front with time in the rotated arc terrane is the result of the westward pivoting of the arc block in front of a zone of extension since Eocene time. Westward migration of bimodal Basin and Range volcanism since at least 16 Ma is tracking rotation of the frontal arc block and growth of the Basin and Range in its wake. -from Author

From prenatal life into senescence, testosterone is essential requirement for manhood.

PubMed

Pradidarcheep, Wisuit; Showpittapornchai, Udomsri

2009-04-01

Prenatally, organisms have the bipotentiality to differentiate along either male or female lines, a process with different stages, each with a narrow window of time, during which testosterone plays a pivotal role in the case of male sexual differentiation. During puberty, the body directs the masculinization process with growth of the genitalia and prostate. Body contours become male, with an average height of 10-15 centimeters greater than that of females, a greater bone and muscle mass, a male hair pattern and a male-type fat distribution. These pubertal developments, largely reversible in case of severe androgen deficiency, require adult levels of testosterone throughout life. A new area of interest is in exploring how far age-related body changes (loss of bone and muscle mass, a shift into a higher ratio of body fat/lean body mass) are part of an age-related decline of testicular testosterone production. Therefore, throughout life, testosterone is essential for a normal male life.

Minireview: Hey U(PS): Metabolic and Proteolytic Homeostasis Linked via AMPK and the Ubiquitin Proteasome System

PubMed Central

Ronnebaum, Sarah M.; Patterson, Cam

2014-01-01

One of the master regulators of both glucose and lipid cellular metabolism is 5′-AMP-activated protein kinase (AMPK). As a metabolic pivot that dynamically responds to shifts in nutrient availability and stress, AMPK dysregulation is implicated in the underlying molecular pathology of a variety of diseases, including cardiovascular diseases, diabetes, cancer, neurological diseases, and aging. Although the regulation of AMPK enzymatic activity by upstream kinases is an active area of research, less is known about regulation of AMPK protein stability and activity by components of the ubiquitin-proteasome system (UPS), the cellular machinery responsible for both the recognition and degradation of proteins. Furthermore, there is growing evidence that AMPK regulates overall proteasome activity and individual components of the UPS. This review serves to identify the current understanding of the interplay between AMPK and the UPS and to promote further exploration of the relationship between these regulators of energy use and amino acid availability within the cell. PMID:25099013

Modulation of the tumor microenvironment by Epstein-Barr virus latent membrane protein 1 in nasopharyngeal carcinoma.

PubMed

Yoshizaki, Tomokazu; Kondo, Satoru; Endo, Kazuhira; Nakanishi, Yosuke; Aga, Mitsuharu; Kobayashi, Eiji; Hirai, Nobuyuki; Sugimoto, Hisashi; Hatano, Miyako; Ueno, Takayoshi; Ishikawa, Kazuya; Wakisaka, Naohiro

2018-02-01

Latent membrane protein 1 (LMP1) is a primary oncogene encoded by the Epstein-Barr virus, and various portions of LMP1 are detected in nasopharyngeal carcinoma (NPC) tumor cells. LMP1 has been extensively studied since the discovery of its transforming property in 1985. LMP1 promotes cancer cell growth during NPC development and facilitates the interaction of cancer cells with surrounding stromal cells for invasion, angiogenesis, and immune modulation. LMP1 is detected in 100% of pre-invasive NPC tumors and in approximately 50% of advanced NPC tumors. Moreover, a small population of LMP1-expressing cells in advanced NPC tumor tissue is proposed to orchestrate NPC tumor tissue maintenance and development through cancer stem cells and progenitor cells. Recent studies suggest that LMP1 activity shifts according to tumor development stage, but it still has a pivotal role during all stages of NPC development. © 2017 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

The continuing role of chemotherapy for advanced non-small cell lung cancer in the targeted therapy era.

PubMed

Lwin, Zarnie; Riess, Jonathan W; Gandara, David

2013-10-01

There have been remarkable advances in the targeted treatment of advanced non-small cell lung cancer (NSCLC) over the past several years. Survival outcomes are steadily improving as management paradigms shift in the diagnosis and treatment of advanced NSCLC. Customizing treatment based on histology and molecular typing has become a standard of care in this era of targeted therapy. While new chemotherapeutic agents have proven effective, the pivotal role of platinum-based chemotherapy doublets has been confirmed. Maintenance chemotherapy has become an option, but who to employ it in remains unclear in the real-world setting. Efforts to overcome resistance to targeted agents are ongoing utilizing combination regimens of chemotherapy plus targeted agents, but optimizing combination strategies needs further exploration. This review highlights recent developments in novel chemotherapeutics and in chemotherapy strategies over the past two years. Despite advances in molecular medicine, there remains an essential role for chemotherapy in advanced NSCLC, even in the recent targeted therapy era.

pH-dependent Differential Scanning Calorimetry and Dynamic Light Scattering Studies of 21:0 PC and 18:0 PS Lipid Binary System

NASA Astrophysics Data System (ADS)

Ali, Rejwan

2010-03-01

Large unilamallar vesicle has been a model system to study many membrane functions. High Tg lipid systems offer many potential biomedical applications in lipid-based delivery applications. While the optimized vesicle functionalities are achieved by Polyethylene Glycol (PEG) polymer, modified PEG and other functional molecule incorporation, however, the host binary lipid system plays the pivotal role in pH-dependent phase transition based lipid vehicular methods. We have investigated a lipid binary system composed of 21:0 PC (1,2-dihenarachidoyl-sn-glycero-3-phosphocholine) and 18:0 PS(1,2-distearoyl-sn-glycero-3-phospho-L-serine). Preliminary studies implementing differential scanning calorimetry shows pH plays key role in temperature shift and thermotropic phase behavior of the binary system. While dynamic light scattering study shows lipid vesicle size is almost independent of pH changes. We will also present pH-dependent thermodynamic parameters to correlate underlying molecular mechanism in relevant pH-range.

Grape Berry Acclimation to Excessive Solar Irradiance Leads to Repartitioning between Major Flavonoid Groups.

PubMed

Reshef, N; Agam, N; Fait, A

2018-04-11

Warm viticulture regions are associated with inferior wines, resulting from the interaction between microclimate and fruit biochemistry. Solar irradiance triggers biosynthetic processes in the fruit and dominates its thermal balance. Therefore, deciphering its impact on fruit metabolism is pivotal to develop strategies for fruit protection and ameliorate its quality traits. Here, we modified light quality and intensity in the fruit-zone and integrated micrometeorology with grape and wine metabolomics, allowing a complete assessment, from field to bottle. We analyzed the dynamics of fruit's adaptation to altered conditions during ripening and constructed temporal-based metabolic networks. Micrometeorological modifications shifted the balance between the major flavonoids, associating increased solar exposure with lower levels of anthocyanins and flavan-3-ols, and higher flavonols. Differences were fixed from 2 weeks postveraison until harvest, suggesting a controlled acclimation response rather than external modulation. Differences in grape composition manifested in the wine and resulted in higher color intensity and improved wine hue under partial shading.

Distraction of the temporomandibular joint condyle in patients with unilateral non-reducing disc displacement: Fact or fiction?

PubMed

Yıldız, Melih; Çağatay Dayan, Süleyman; Şakar, Olcay; Sülün, Tonguç

2017-07-24

This study investigated the distractive effect of a unilateral pivot splint on patients with unilateral disc displacement without reduction. The study group was comprised of 18 patients who had no history of treatment with removable prosthetic restorations of molars, premolars, or canine teeth, and no previous treatment for temporomandibular disorder. Joint spaces measurements made on magnetic resonance images indicated the affected side to be narrower than the healthy side. Unilateral distraction splints were made for all patients. An ultrasonic motion analyzer was used to measure the vertical shift occurring on the affected side as patients closed their mouths with maximal force with the splint in their mouths. Closing with maximal force on the unilateral distraction splint led to a noticeable downward movement of the affected condyle. The findings of this study indicate that the TMJ condyle of patients with unilateral disc displacement without reduction may be unilaterally distracted if the articular space is narrowed.

Temperature-dependent body size effects determine population responses to climate warming.

PubMed

Lindmark, Max; Huss, Magnus; Ohlberger, Jan; Gårdmark, Anna

2018-02-01

Current understanding of animal population responses to rising temperatures is based on the assumption that biological rates such as metabolism, which governs fundamental ecological processes, scale independently with body size and temperature, despite empirical evidence for interactive effects. Here, we investigate the consequences of interactive temperature- and size scaling of vital rates for the dynamics of populations experiencing warming using a stage-structured consumer-resource model. We show that interactive scaling alters population and stage-specific responses to rising temperatures, such that warming can induce shifts in population regulation and stage-structure, influence community structure and govern population responses to mortality. Analysing experimental data for 20 fish species, we found size-temperature interactions in intraspecific scaling of metabolic rate to be common. Given the evidence for size-temperature interactions and the ubiquity of size structure in animal populations, we argue that accounting for size-specific temperature effects is pivotal for understanding how warming affects animal populations and communities. © 2017 The Authors. Ecology Letters published by CNRS and John Wiley & Sons Ltd.

[Case study of red water phenomenon in drinking water distribution systems caused by water source switch].

PubMed

Wang, Yang; Zhang, Xiao-jian; Chen, Chao; Pan, An-jun; Xu, Yang; Liao, Ping-an; Zhang, Su-xia; Gu, Jun-nong

2009-12-01

Red water phenomenon occurred in some communities of a city in China after water source switch in recent days. The origin of this red water problem and mechanism of iron release were investigated in the study. Water quality of local and new water sources was tested and tap water quality in suffered area had been monitored for 3 months since red water occurred. Interior corrosion scales on the pipe which was obtained from the suffered area were analyzed by XRD, SEM, and EDS. Corrosion rates of cast iron under the conditions of two source water were obtained by Annular Reactor. The influence of different source water on iron release was studied by pipe section reactor to simulate the distribution systems. The results indicated that large increase of sulfate concentration by water source shift was regarded as the cause of red water problem. The Larson ratio increased from about 0.4 to 1.7-1.9 and the red water problem happened in the taps of some urban communities just several days after the new water source was applied. The mechanism of iron release was concluded that the stable shell of scales in the pipes had been corrupted by this kind of high-sulfate-concentration source water and it was hard to recover soon spontaneously. The effect of sulfate on iron release of the old cast iron was more significant than its effect on enhancing iron corrosion. The rate of iron release increased with increasing Larson ratio, and the correlation of them was nonlinear on the old cast-iron. The problem remained quite a long time even if the water source re-shifted into the blended one with only small ratio of the new source and the Larson ratio reduced to about 0.6.

Laser Polarization Effect on Molecular Harmonic and Elliptically Polarized Attosecond Pulse Generation

NASA Astrophysics Data System (ADS)

Feng, Li-Qiang; Li, Wen-Liang; Liu, Hang

2017-01-01

Molecular harmonic spectra of {{{H}}}2+ driven by the linearly polarized laser pulses with different polarized angles have been theoretically investigated through solving the two-dimensional time-dependent Schrödinger equation. (i) Below-threshold harmonic spectra show a visible enhanced peak around the 7th harmonic (H7), which produces a red-shift phenomenon as the internuclear distance increased. Theoretical analyses show the red-shift enhanced peak is caused by the laser-induced electron transfer between the ground state and the 1st excited state of {{{H}}}2+. (ii) Due to the two-centre interference phenomenon, the above-threshold harmonic spectra exhibit many maxima and minima. (iii) With the introduction of the polarized angle, the anomalous elliptically polarized harmonics can be found. But, with the introduction of the spatial inhomogeneous effect, not only the ellipticities of the harmonics are equal to a stable value of \\varepsilon ˜ 0.1-0.3, but also the harmonic cutoffs are extended. As a result, four super-bandwidths of 407 eV, 310 eV, 389 eV, and 581 eV can be obtained. Time profiles of the harmonic generations have been shown to explain the harmonic characteristics. Finally, a series of elliptically polarized (\\varepsilon ˜ 0.1-0.3) attosecond X-ray pulses with durations from 18as to 25as can be directly produced through Fourier transformation of the spectral continuum. Supported by National Natural Science Foundation of China under Grant No. 11504151, Doctoral Scientific Research Foundation of Liaoning Province under Grant No. 201501123 and Scientific Research Fund of Liaoning Provincial Education Department under Grant No. L2014242

Fatigue in U.S. Astronauts Onboard the International Space Station: Environmental Factors, Operational Impacts, and Implementation of Countermeasures

NASA Technical Reports Server (NTRS)

Scheuring, R. A.; Moomaw, R. C.; Johnston, S. L.

2014-01-01

Since 2000, US astronauts have been supporting missions up to a six month duration on the International Space Station (ISS). Crewmembers have experienced fatigue for reasons similar to military deployments. Astronauts experience psychological stressors such as heavy workloads, extended duty periods, circadian misalignment, inadequate/ineffective sleep, and loss of the environmental cues of a gravity environment. Complicating the psychological stressors are environmental factors; distracting background noise, unexpected and variable mission schedules, unfavorable thermal control, elevated CO2 levels, and an unusual sleep environment with schedules that impinge on pre-sleep periods. Physiological contributors to poor sleep and fatigue include a cephalad fluid shift and back pain. Restful sleep is further challenged due to a lack of gravity-related proprioceptive cues and need for restraints. The term "space fog" has been used by astronauts to describe a phenomenon of forgetfulness, slowed reaction time and transient confusion while trying to complete tasks. There is a distinct temporal correlation with arrival on the Space Station and the onset of slowed cognitive skills and a spontaneous resolution that may take up to 6 weeks. The Genesis of this phenomenon may be chronic fatigue secondary to transitioning from a planar environment to a 360deg microgravity perspective. Recently, countermeasures to improve sleep duration and quality in astronauts on the ISS have been instituted with moderate degrees of success as measured by self-reaction time (psychomotor vigilance task testing), actigraphy, and subjective reports. Judicious use of stimulants and hypnotics, light therapy, controlled sleep periods and sleep shifting and reducing ambient CO2 levels are a few of the most promising countermeasures being used in space to improve sleep and reduce fatigue.

Evolution of mechanical properties of ultrafine grained 1050 alloy annealing with electric current

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cao, Yiheng; He, Lizi, E-mail: helizi@epm.neu.edu.cn; Zhang, Lin

2016-03-15

The tensile properties and microstructures of 1050 aluminum alloy prepared by equal channel angular pressing at cryogenic temperature (cryoECAP) after electric current annealing at 90–210 °C for 3 h were investigated by tensile test, electron back scattering diffraction (EBSD) and transmission electron microscopy (TEM). An unexpected annealing-induced strengthening phenomenon occurs at 90–210 °C, due to a significant decrease in the density of mobile dislocations after annealing, and thus a higher yield stress is required to nucleate alternative dislocation sources during tensile test. The electric current can enhance the motion of dislocations, lead to a lower dislocation density at 90–150 °C,more » and thus shift the peak annealing temperature from 150 °C to 120 °C. Moreover, the electric current can promote the migration of grain boundaries at 150–210 °C, result in a larger grain size at 150 °C and 210 °C, and thus causes a lower yield stress. The sample annealed with electric current has a lower uniform elongation at 90–120 °C, and the deviation in the uniform elongation between samples annealed without and with electric current becomes smaller at 150–210 °C. - Highlights: • An unexpected annealing-induced strengthening phenomenon occurs at 90–210 °C. • The d. c. current can enhance the motion of dislocations at 90–150 °C, and thus shift the peak annealing temperature from 150 °C to 120 °C. • The d. c. current can promote the grain growth at 150–210 °C, and thus cause a lower yield stress. • The DC annealed sample has a lower uniform elongation at 90–120 °C.« less

Ag@ZnO core-shell nanoparticles study by first principle: The structural, magnetic and optical properties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cheng, Hai-Xia; Wang, Xiao-Xu; Beijing Computing Center, Beijing 100094

Ag@ZnO core-shell nanoparticles of around 72 atoms have been investigated by the density functional theory, revealing proving for the first time that the core-shell structure exhibits a shrinkage phenomenon from outer shell in agreement with the other studies in literatures. Our calculations predict that the Ag@ZnO core-shell structure is a ferromagnetic spin polarized state, and the magnetism mainly stems from the spin splitting of 2p electrons of O atoms. In addition, the total and partial DOS of Ag@ZnO indicate that the nanostructure is a half-metallic nanoparticle and has the characters of the p-type semiconductor. Furthermore, the optical properties calculations showmore » that the absorption edge of Ag@ZnO have a red shift and good photocatalysis compare to that of the bulk ZnO. These results of the Ag@ZnO core-shell structure obtain a well agreement with the experimental measurement. - Graphical abstract: Geometric structure of (a) Ag@ZnO core-shell nanostructure; (b) the core of Ag; (c) the shell of ZnO The core-shell nanoparticle Ag@ZnO contains Ag inner core of radius of 4 Å and ZnO outer shell with thickness of 2 Å. Ag@ZnO core-shell nanoparticles of around 72 atoms have been proved for the first time that the core-shell structure exhibit a shrinkage phenomenon from outer shell. Our calculations predict that the Ag@ZnO core-shell structure is a half-metallic nanoparticle and has the characters of the p-type semiconductor. The absorption edge of Ag@ZnO have a red shift and get good photo-catalysis compare to that of the bulk ZnO.« less

Shifts in historical streamflow extremes in the Colorado River Basin

DOE PAGES

Solander, Kurt C.; Bennett, Katrina Eleanor; Middleton, Richard Stephen

2017-07-10

The global phenomenon of climate change-induced shifts in precipitation leading to "wet regions getting wetter" and "dry regions getting drier" has been widely studied. However, the propagation of these changes in atmospheric moisture within stream channels is not a direct relationship due to differences in the timing of how changing precipitation patterns interact with various land surfaces. Streamflow is of particular interest in the Colorado River Basin (CRB) due to the region’s rapidly growing population, projected temperature increases that are expected to be higher than elsewhere in the contiguous United States, and subsequent climate-driven disturbances including drought, vegetation mortality, andmore » wildfire, which makes the region more vulnerable to changes in hydrologic extremes. Here in this study, we determine how streamflow extremes have shifted in the CRB using two statistical methods—the Mann-Kendall trend detection analysis and Generalized Extreme Value (GEV) theorem. We evaluate these changes in the context of key flow metrics that include high and low flow percentiles, maximum and minimum 7-day flows, and the center timing of streamflow using historical gage records representative of natural flows. Monthly results indicate declines of up to 41% for high and low flows during the June to July peak runoff season, while increases of up to 24% were observed earlier from March to April. Finally, our results highlight a key threshold elevation and latitude of 2300 m and 39° North, respectively, where there is a distinct shift in the trend. The spatiotemporal patterns observed are indicative of changing snowmelt patterns as a primary cause of the shifts. Identification of how this change varies spatially has consequences for improved land management strategies, as specific regions most vulnerable to threats can be prioritized for mitigation or adaptation as the climate warms.« less

Shifts in historical streamflow extremes in the Colorado River Basin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Solander, Kurt C.; Bennett, Katrina Eleanor; Middleton, Richard Stephen

The global phenomenon of climate change-induced shifts in precipitation leading to "wet regions getting wetter" and "dry regions getting drier" has been widely studied. However, the propagation of these changes in atmospheric moisture within stream channels is not a direct relationship due to differences in the timing of how changing precipitation patterns interact with various land surfaces. Streamflow is of particular interest in the Colorado River Basin (CRB) due to the region’s rapidly growing population, projected temperature increases that are expected to be higher than elsewhere in the contiguous United States, and subsequent climate-driven disturbances including drought, vegetation mortality, andmore » wildfire, which makes the region more vulnerable to changes in hydrologic extremes. Here in this study, we determine how streamflow extremes have shifted in the CRB using two statistical methods—the Mann-Kendall trend detection analysis and Generalized Extreme Value (GEV) theorem. We evaluate these changes in the context of key flow metrics that include high and low flow percentiles, maximum and minimum 7-day flows, and the center timing of streamflow using historical gage records representative of natural flows. Monthly results indicate declines of up to 41% for high and low flows during the June to July peak runoff season, while increases of up to 24% were observed earlier from March to April. Finally, our results highlight a key threshold elevation and latitude of 2300 m and 39° North, respectively, where there is a distinct shift in the trend. The spatiotemporal patterns observed are indicative of changing snowmelt patterns as a primary cause of the shifts. Identification of how this change varies spatially has consequences for improved land management strategies, as specific regions most vulnerable to threats can be prioritized for mitigation or adaptation as the climate warms.« less

Facial Soft Tissue Measurement in Microgravity-induces Fluid Shifts

NASA Technical Reports Server (NTRS)

Marshburn, Thomas; Cole, Richard; Pavela, James; Garcia, Kathleen; Sargsyan, Ashot

2014-01-01

Fluid shifts are a well-known phenomenon in microgravity, and one result is facial edema. Objective measurement of tissue thickness in a standardized location could provide a correlate with the severity of the fluid shift. Previous studies of forehead tissue thickness (TTf) suggest that when exposed to environments that cause fluid shifts, including hypergravity, head-down tilt, and high-altitude/lowpressure, TTf changes in a consistent and measurable fashion. However, the technique in past studies is not well described or standardized. The International Space Station (ISS) houses an ultrasound (US) system capable of accurate sub-millimeter measurements of TTf. We undertook to measure TTf during long-duration space flight using a new accurate, repeatable and transferable technique. Methods: In-flight and post-flight B-mode ultrasound images of a single astronaut's facial soft tissues were obtained using a Vivid-q US system with a 12L-RS high-frequency linear array probe (General Electric, USA). Strictly mid-sagittal images were obtained involving the lower frontal bone, the nasofrontal angle, and the osseo-cartilaginous junction below. Single images were chosen for comparison that contained identical views of the bony landmarks and identical acoustical interface between the probe and skin. Using Gingko CADx DICOM viewing software, soft tissue thickness was measured at a right angle to the most prominent point of the inferior frontal bone to the epidermis. Four independent thickness measurements were made. Conclusions: Forehead tissue thickness measurement by ultrasound in microgravity is feasible, and our data suggest a decrease in tissue thickness upon return from microgravity environment, which is likely related to the cessation of fluid shifts. Further study is warranted to standardize the technique with regard to the individual variability of the local anatomy in this area.

Spot-Welding Gun With Pivoting Twin-Collet Assembly

NASA Technical Reports Server (NTRS)

Nguyen, Francis; Simpson, Gareth; Hoult, William S.

1996-01-01

Modified spot-welding gun includes pivoting twin-collet assembly that holds two spot-welding electrodes. Designed to weld highly conductive (30 percent gold) brazing-alloy foils to thin nickel alloy workpieces; also suitable for other spot-welding applications compatible with two-electrode configuration.

Spatial ET field mapping using sensors mounted on a center pivot

USDA-ARS?s Scientific Manuscript database

Site-specific irrigation management is becoming more important for improving crop water use efficiency and reducing water wastage, especially as competition for quality water resources increases. Continuous geo-referenced canopy temperature measurements using sensors mounted on a center pivot irriga...

SiRen: Leveraging Similar Regions for Efficient and Accurate Variant Calling

DTIC Science & Technology

2015-05-30

Cloudera, EMC2, Ericsson, Facebook, Guavus, HP, Huawei, Informatica , Intel, Microsoft, NetApp, Pivotal, Samsung, Schlumberger, Splunk, Virdata and VMware...EMC2, Ericsson, Facebook, Guavus, HP, Huawei, Informatica , Intel, Microsoft, NetApp, Pivotal, Samsung, Schlumberger, Splunk, Virdata and VMware

Localized surface plasmon resonance of nanotriangle dimers at different relative positions

NASA Astrophysics Data System (ADS)

Ren, Yatao; Qi, Hong; Chen, Qin; Wang, Shenling; Ruan, Liming

2017-09-01

The investigation of nanoparticle's optical properties is crucial for their biological and therapeutic applications. In the present work, a promising type of gold nanoparticle, the triangular prism which was reported to have multipolar surface plasmon peaks, was studied. The Plasmon ruler effect of nanotriangle dimers was observed and investigated for the first time. Well-defined trends of the extinction spectra maxima, which have a linear correlation with the triangle edge length, for lower order extinction corresponding to in-plane mode, were observed. On this basis, the optical property of nanotriangle dimers with different arrangements, including two nanotriangles aligned side-by-side, bottom-to-bottom, and in line, were studied. For the side-by-side arrangement, an additional peak was generated on the red shift side of the peak corresponding to dipole mode. When the distance between two prisms was scaled by the triangular side length, the relative plasmon shift can be approximated as an exponential function of the relative offset distance. Moreover, for dimers with nanotriangles arranged in line, there was a global blue shift of the extinction spectra with the approaching of two particles, including the higher order mode extinction. An interesting phenomenon was found for dimers with two nanotriangles aligned bottom-to-bottom. The resonance band split into two bands with the decreasing of the offset distance.

Viewing condition dependence of the gaze-evoked nystagmus in Arnold Chiari type 1 malformation.

PubMed

Ghasia, Fatema F; Gulati, Deepak; Westbrook, Edward L; Shaikh, Aasef G

2014-04-15

Saccadic eye movements rapidly shift gaze to the target of interest. Once the eyes reach a given target, the brainstem ocular motor integrator utilizes feedback from various sources to assure steady gaze. One of such sources is cerebellum whose lesion can impair neural integration leading to gaze-evoked nystagmus. The gaze evoked nystagmus is characterized by drifts moving the eyes away from the target and a null position where the drifts are absent. The extent of impairment in the neural integration for two opposite eccentricities might determine the location of the null position. Eye in the orbit position might also determine the location of the null. We report this phenomenon in a patient with Arnold Chiari type 1 malformation who had intermittent esotropia and horizontal gaze-evoked nystagmus with a shift in the null position. During binocular viewing, the null was shifted to the right. During monocular viewing, when the eye under cover drifted nasally (secondary to the esotropia), the null of the gaze-evoked nystagmus reorganized toward the center. We speculate that the output of the neural integrator is altered from the bilateral conflicting eye in the orbit position secondary to the strabismus. This could possibly explain the reorganization of the location of the null position. Copyright © 2014 Elsevier B.V. All rights reserved.

Wind turbines and bat mortality: Doppler shift profiles and ultrasonic bat-like pulse reflection from moving turbine blades.

PubMed

Long, Chloe V; Flint, James A; Lepper, Paul A

2010-10-01

Bat mortality resulting from actual or near-collision with operational wind turbine rotors is a phenomenon that is widespread but not well understood. Because bats rely on information contained in high-frequency echoes to determine the nature and movement of a target, it is important to consider how ultrasonic pulses similar to those used by bats for echolocation may be interacting with operational turbine rotor blades. By assessing the characteristics of reflected ultrasonic echoes, moving turbine blades operating under low wind speed conditions (<6 m s(-1)) were found to produce distinct Doppler shift profiles at different angles to the rotor. Frequency shifts of up to ±700-800 Hz were produced, which may not be perceptible by some bat species. Monte Carlo simulation of bat-like sampling by echolocation revealed that over 50 rotor echoes could be required by species such as Pipistrellus pipistrellus for accurate interpretation of blade movement, which may not be achieved in the bat's approach time-window. In summary, it was found that echoes returned from moving blades had features which could render them attractive to bats or which might make it difficult for the bat to accurately detect and locate blades in sufficient time to avoid a collision.

Element specificity of ortho-positronium annihilation for alkali-metal loaded SiO2 glasses.

PubMed

Sato, K; Hatta, T

2015-03-07

Momentum distributions associated with ortho-positronium (o-Ps) pick-off annihilation photon are often influenced by light elements, as, e.g., carbon, oxygen, and fluorine. This phenomenon, so-called element specificity of o-Ps pick-off annihilation, has been utilized for studying the elemental environment around the open spaces. To gain an insight into the element specificity of o-Ps pick-off annihilation, the chemical shift of oxygen 1s binding energy and the momentum distributions associated with o-Ps pick-off annihilation were systematically investigated for alkali-metal loaded SiO2 glasses by means of X-ray photoelectron spectroscopy and positron-age-momentum correlation spectroscopy, respectively. Alkali metals introduced into the open spaces surrounded by oxygen atoms cause charge transfer from alkali metals to oxygen atoms, leading to the lower chemical shift for the oxygen 1s binding energy. The momentum distribution of o-Ps localized into the open spaces is found to be closely correlated with the oxygen 1s chemical shift. This correlation with the deepest 1s energy level evidences that the element specificity of o-Ps originates from pick-off annihilation with orbital electrons, i.e., dominantly with oxygen 2p valence electrons and s electrons with lower probability.

Developmental continuity in reward-related enhancement of cognitive control.

PubMed

Strang, Nicole M; Pollak, Seth D

2014-10-01

Adolescents engage in more risky behavior than children or adults. The most prominent hypothesis for this phenomenon is that brain systems governing reward sensitivity and brain systems governing self-regulation mature at different rates. Those systems governing reward sensitivity mature in advance of those governing self-control. This hypothesis has substantial empirical support, however, the evidence supporting this theory has been exclusively derived from contexts where self-control systems are required to regulate reward sensitivity in order to promote adaptive behavior. In adults, reward promotes a shift to a proactive control strategy and better cognitive control performance. It is unclear whether children and adolescents will respond to reward in the same way. Using fMRI methodology, we explored whether children and adolescents would demonstrate a shift to proactive control in the context of reward. We tested 22 children, 20 adolescents, and 23 adults. In contrast to our hypothesis, children, adolescents, and adults all demonstrated a shift to proactive cognitive control in the context of reward. In light of the results, current neurobiological theories of adolescent behavior need to be refined to reflect that in certain contexts there is continuity in the manner reward and cognitive control systems interact across development. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Effects of an Off-Axis Pivoting Elliptical Training Program on Gait Function in Persons With Spastic Cerebral Palsy: A Preliminary Study.

PubMed

Tsai, Liang-Ching; Ren, Yupeng; Gaebler-Spira, Deborah J; Revivo, Gadi A; Zhang, Li-Qun

2017-07-01

This preliminary study examined the effects of off-axis elliptical training on reducing transverse-plane gait deviations and improving gait function in 8 individuals with cerebral palsy (CP) (15.5 ± 4.1 years) who completed an training program using a custom-made elliptical trainer that allows transverse-plane pivoting of the footplates during exercise. Lower-extremity off-axis control during elliptical exercise was evaluated by quantifying the root-mean-square and maximal angular displacement of the footplate pivoting angle. Lower-extremity pivoting strength was assessed. Gait function and balance were evaluated using 10-m walk test, 6-minute-walk test, and Pediatric Balance Scale. Toe-in angles during gait were quantified. Participants with CP demonstrated a significant decrease in the pivoting angle (root mean square and maximal angular displacement; effect size, 1.00-2.00) and increase in the lower-extremity pivoting strength (effect size = 0.91-1.09) after training. Reduced 10-m walk test time (11.9 ± 3.7 seconds vs. 10.8 ± 3.0 seconds; P = 0.004; effect size = 1.46), increased Pediatric Balance Scale score (43.6 ± 12.9 vs. 45.6 ± 10.8; P = 0.042; effect size = 0.79), and decreased toe-in angle (3.7 ± 10.5 degrees vs. 0.7 ± 11.7 degrees; P = 0.011; effect size = 1.22) were observed after training. We present an intervention to challenge lower-extremity off-axis control during a weight-bearing and functional activity for individuals with CP. Our preliminary findings suggest that this intervention was effective in enhancing off-axis control, gait function, and balance and reducing in-toeing gait in persons with CP.