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Effects of random pinning on the potential energy landscape of a supercooled liquid.
We use energy landscape methods to investigate the response of a supercooled liquid to random pinning. We classify the structural similarity of different energy minima using a measure of overlap. This analysis reveals a correspondence between distinct particle packings (which are characterised via the overlap) and funnels on the energy landscape (which are characterised via disconnectivity graphs). As the number of pinned particles is increased, we find a crossover from glassy behavior at low pinning to a structure-seeking landscape at high pinning, in which all thermally accessible minima are structurally similar. We discuss the consequences of these results for theories of randomly pinned liquids. We also investigate how the energy landscape depends on the fraction of pinned particles, including the degree of frustration and the evolution of distinct packings as the number of pinned particles is reduced.epsr
Effet de la composition de différents substrats culturaux sur quelques paramÚtres de croissance de Gambeya lacourtiana De Wild en pépiniÚre au nordest du Gabon
Objectif : Les connaissances en matiĂšre de gestion des ressources phytogĂ©nĂ©tiques en zone tropicale humide sont encore limitĂ©es au regard de la variabilitĂ© biologique existante. Un programme de multiplication d'espĂšces forestiĂšres a Ă©tĂ© entrepris au nord-est du Gabon. La simplicitĂ© des techniques et leur faible coĂ»t ont favorisĂ© la production de milliers de plants. Nos travaux sâintĂšgrent dans ce projet afin dâĂ©valuer les effets de la composition de trois substrats culturaux sur quelques paramĂštres de croissance de Gambeya lacourtiana De Wild (SapotacĂ©es) en pĂ©piniĂšre.MĂ©thodologie et rĂ©sultats : Cette expĂ©rimentation en sachets de film plastique de polyĂ©thylĂšne a Ă©tĂ©Â conduite en 2010 Ă Ipassa (Gabon) en conditions naturelles dâĂ©clairement, de tempĂ©rature et dâhygromĂ©trie. Trois substrats culturaux S1 (30% sable + 70% terre noire), S2 (20% terre noire + 70% sciure de bois + 10% sable) et S3 (70% cendre de bois + 30% sable) ont constituĂ© le milieu de culture. AprĂšs la prĂ©paration manuelle des substrats, les sachets remplis ont Ă©tĂ© placĂ©s suivant un dispositif en blocs complĂ©ment randomisĂ©s Ă vingt (20) unitĂ©s expĂ©rimentales. Les rĂ©sultats ont montrĂ© que le substrat S1 a induit le meilleur accroissement des plants. Le substrat S3 sâest rĂ©vĂ©lĂ© nocif Ă la croissance des plantules. La prĂ©sence de sciure de bois dans le substrat S2 sâest montrĂ©e inefficace pour la germination des graines, mais ce substrat a donnĂ© des performances acceptables sur la croissance longitudinale des plantules.Conclusion et application : Lâapport de matiĂšre organique serait donc plus bĂ©nĂ©fique pour la croissance des plantules de G. lacourtiana alors quâun milieu composĂ© de sable et de terre humifĂšre reste suffisant pour la germination de semences.Mots clĂ©s : multiplication vĂ©gĂ©tale, substrat cultural, paramĂštres de croissance, Gambeya lacourtiana, Gabon.Effects of the composition of different farming substrates on some growth parameters of Gambeya lacourtiana De Wild in seedbed in north-eastern of GabonABSTRACTObjective: Knowledge in plant resources management in tropical rainfall area is still limited because of the great biological variability existing. A program of multiplication of wild species was undertaken in the northeastern of Gabon. The simplicity of the techniques and their low costs supported the production of thousands of seedlings. Our study integrates this project with a view to evaluate the effects of the composition of three farming substrates on some growth parameters of Gambeya lacourtiana De Wild (Sapotaceae) in seedbed.Methodology and Results: This experiment in polyethylene bags took place in 2010 at Ipassa (Gabon) based on natural conditions of lightness, temperature and relative humidity. Three substrates S1 (30% sand + 70% black soil), S2 (20% black soil + 70% sawdust +10% sand) and S3 (70% wood + 30% sand) were used as culture media. After manual preparation of substrate, bags filled were placed according to a complete with twenty (20) repetitions. Results show that the substrate S1 was found to induce the best increase of planlets. The chemical composition of the S3 substrate appeared to be harmful on the growth of the plantlets. The presence of sawdust in the S2 substrate was ineffective for the germination of seeds, but this substrate gave suitable performances on the longitudinal growth of the seedlings.Conclusion and Application: Organic matter is more required for the growing of plantlets of G. lacourtiana while a substrate composed by sand and black soil is efficient for the seedlings germination.Key-words: vegetative multiplication, farming substrate, growth parameters, Gambeya lacourtiana, Gabon
Amygdaloid involvement in the defensive behavior of mice exposed to the open elevated plus-maze
Previous studies have shown that the exposure to an open elevated plus maze (oEPM, an EPM with all four open arms) elicits fear/anxiety-related responses in laboratory rodents. However, very little is known about the underlying neural substrates of these defensive behaviors. Accordingly, the present study investigated the effects of chemical inactivation of the amygdala [through local injection of cobalt chloride (CoCl2: a nonspecific synaptic blocker)] on the behavior of oEPM-exposed mice. In a second experiment, the pattern of activation of the basolateral (BLA) and central (CeA) nuclei of the amygdala was assessed through quantification of Fos protein expression in mice subjected to one of several behavioral manipulations. To avoid the confound of acute handling stress, 4 independent groups of mice were habituated daily for 10 days to an enclosed EPM (eEPM) and, on day 11 prior to immunohistochemistry, were either taken directly from their home cage (control) or individually exposed for 10 min to a new clean holding cage (novelty), an eEPM, or the oEPM. An additional group of mice (maze-naĂŻve) was not subjected to either the habituation or exposure phase but were simply chosen at random from their home cages to undergo an identical immunohistochemistry procedure. Results showed that amygdala inactivation produced an anxiolytic-like profile comprising reductions in time spent in the proximal portions of the open arms and total stretched attend postures (SAP) as well as increases in time spent in the distal portions of the open arms and total head-dipping. Moreover, Fos-positive labeled cells were bilaterally increased in the amygdaloid complex, particularly in the BLA, of oEPM-exposed animals compared to all other groups. These results suggest that the amygdala (in particular, its BLA nucleus) plays a key role in the modulation of defensive behaviors in oEPM-exposed mice
Deprivation, clubs and drugs: results of a UK regional population-based cross-sectional study of weight management strategies
Background
Despite rising levels of obesity in England, little is known about slimming club and weight loss drug (medication) use or users. In order to inform future commissioning, we report the prevalence of various weight management strategies and examine the associations between slimming club and medication use and age, gender, deprivation and body mass index.
Methods
A population based cross-sectional survey of 26,113 adults was conducted in South Yorkshire using a self-completed health questionnaire. Participants were asked whether they had ever used the following interventions to manage their weight: increasing exercise, healthy eating, controlling portion size, slimming club, over the counter weight loss medication, or meal replacements. Factors associated with slimming club and weight-loss medication use were explored using logistic regression.
Results
Over half of the sample was either overweight (36.6%) or obese (19.6%). Obesity was more common in the most deprived areas compared to the least deprived (26.3% vs. 12.0%). Healthy eating (49.0%), controlling portion size (43.4%), and increasing exercise (43.0%) were the most commonly reported weight management strategies. Less common strategies were attending a slimming club (17.2%), meal replacements (3.4%) and weight-loss medication (3.2%). Adjusting for BMI, age, deprivation and long standing health conditions, women were significantly more likely to report ever using a slimming club (adjusted OR = 18.63, 95% CI = 16.52â21.00) and more likely to report ever using over the counter weight-loss medications (AOR = 3.73, 95% CI = 3.10-4.48), while respondents from the most deprived areas were less likely to report using slimming clubs (AOR = 0.60, 95% CI = 0.53-0.68), and more likely to reporting using weight loss medications (AOR =1.38, 95% CI = 1.05-1.82).
Conclusion
A large proportion of individuals report having used weight management strategies. Slimming clubs and over-the-counter weight loss medication account for a smaller proportion of the overall uptake. Those from less deprived areas were more likely to use slimming clubs while those from more deprived areas were more likely to use weight-loss medications. Future NHS and Local Authority commissioning of weight management services must be aware of this varying social gradient in weight management strategies
Application of REVEAL Lite 2 and COMPERA 2.0 risk scores to patients with pulmonary arterial hypertension switching to riociguat in the REPLACE study
\ua9 2024In Riociguat rEplacing PDE5i therapy evaLuated Against Continued PDE5i thErapy (REPLACE) (NCT02891850), improvements in risk status were observed in patients with pulmonary arterial hypertension (PAH) at intermediate risk switching to riociguat versus continuing phosphodiesterase-5 inhibitors (PDE5i). This post hoc study applied the Registry to Evaluate Early and Long-Term PAH Disease Management (REVEAL) Lite 2 and Comparative Prospective Registry of Newly Initiated Therapies for Pulmonary (COMPERA) 2.0 risk-assessment tools to REPLACE to investigate the impact of baseline risk status on clinical improvement. The proportions of riociguat- and PDE5i-treated patients achieving the primary end-point at REVEAL Lite 2 low, intermediate, and high baseline risk reflected the overall population. Proportions of riociguat-treated patients achieving the primary end-point were comparable between the COMPERA 2.0 intermediate-low risk (39%) and intermediate-high risk (43%) groups. Our findings show that patients in REPLACE achieved clinical improvement by switching from PDE5i to riociguat across all COMPERA 2.0 and most REVEAL Lite 2 baseline risk strata
Influence of different beverages on the force degradation of intermaxillary elastics: an in vitro study
OBJECTIVE: The aim of this study was to evaluate in vitro the effects of frequently ingested beverages on force degradation of intermaxillary elastics. MATERIAL AND METHODS: One hundred and eighty 1/4-inch intermaxillary elastics (TP Orthodontics) were immersed into six different beverages: (1) Coca-Cola(Âź); (2) Beer; (3) Orange juice; (4) Red wine; (5) Coffee and (6) artificial saliva (control). The period of immersion was 15 min for the first and second cycles and 30 min for the third to fifth cycles. Tensile forces were read in a tensile testing machine before and after the five immersion cycles. One-way repeated measures ANOVA was used to identify significant differences. RESULTS: Force degradation was seen in all evaluated groups and at all observation periods (p<0.05). A greater degree of degradation was present at the initial periods, decreasing gradually over time. However, no statistically significant differences were seen among groups at the same periods, showing that different groups behaved similarly. CONCLUSION: The chemical nature of the evaluated beverages was not able to influence the degree of force degradation at all observation periods
A new concept for the combination of optical interferometers and high-resolution spectrographs
The combination of high spatial and spectral resolution in optical astronomy
enables new observational approaches to many open problems in stellar and
circumstellar astrophysics. However, constructing a high-resolution
spectrograph for an interferometer is a costly and time-intensive undertaking.
Our aim is to show that, by coupling existing high-resolution spectrographs to
existing interferometers, one could observe in the domain of high spectral and
spatial resolution, and avoid the construction of a new complex and expensive
instrument. We investigate in this article the different challenges which arise
from combining an interferometer with a high-resolution spectrograph. The
requirements for the different sub-systems are determined, with special
attention given to the problems of fringe tracking and dispersion. A concept
study for the combination of the VLTI (Very Large Telescope Interferometer)
with UVES (UV-Visual Echelle Spectrograph) is carried out, and several other
specific instrument pairings are discussed. We show that the proposed
combination of an interferometer with a high-resolution spectrograph is indeed
feasible with current technology, for a fraction of the cost of building a
whole new spectrograph. The impact on the existing instruments and their
ongoing programs would be minimal.Comment: 27 pages, 9 figures, Experimental Astronomy; v2: accepted versio
A systematic review and meta-synthesis of the impact of low back pain on people's lives
Copyright @ 2014 Froud et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative
Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and
reproduction in any medium, provided the original work is properly credited.Background - Low back pain (LBP) is a common and costly problem that many interpret within a biopsychosocial model. There is renewed concern that core-sets of outcome measures do not capture what is important. To inform debate about the coverage of back pain outcome measure core-sets, and to suggest areas worthy of exploration within healthcare consultations, we have synthesised the qualitative literature on the impact of low back pain on peopleâs lives.
Methods - Two reviewers searched CINAHL, Embase, PsycINFO, PEDro, and Medline, identifying qualitative studies of peopleâs experiences of non-specific LBP. Abstracted data were thematic coded and synthesised using a meta-ethnographic, and a meta-narrative approach.
Results - We included 49 papers describing 42 studies. Patients are concerned with engagement in meaningful activities; but they also want to be believed and have their experiences and identity, as someone âdoing battleâ with pain, validated. Patients seek diagnosis, treatment, and cure, but also reassurance of the absence of pathology. Some struggle to meet social expectations and obligations. When these are achieved, the credibility of their pain/disability claims can be jeopardised. Others withdraw, fearful of disapproval, or unable or unwilling to accommodate social demands. Patients generally seek to regain their pre-pain levels of health, and physical and emotional stability. After time, this can be perceived to become unrealistic and some adjust their expectations accordingly.
Conclusions - The social component of the biopsychosocial model is not well represented in current core-sets of outcome measures. Clinicians should appreciate that the broader impact of low back pain includes social factors; this may be crucial to improving patientsâ experiences of health care. Researchers should consider social factors to help develop a portfolio of more relevant outcome measures.Arthritis Research U
Midday measurements of leaf water potential and stomatal conductance are highly correlated with daily water use of Thompson Seedless grapevines
A study was conducted to determine the relationship between midday measurements of vine water status and daily water use of grapevines measured with a weighing lysimeter. Water applications to the vines were terminated on August 24th for 9 days and again on September 14th for 22 days. Daily water use of the vines in the lysimeter (ETLYS) was approximately 40 L vineâ1 (5.3 mm) prior to turning the pump off, and it decreased to 22.3 L vineâ1 by September 2nd. Pre-dawn leaf water potential (ΚPD) and midday Κl on August 24th were â0.075 and â0.76 MPa, respectively, with midday Κl decreasing to â1.28 MPa on September 2nd. Leaf g s decreased from ~500 to ~200 mmol mâ2 sâ1 during the two dry-down periods. Midday measurements of g s and Κl were significantly correlated with one another (r = 0.96) and both with ETLYS/ETo (r = ~0.9). The decreases in Κl, g s, and ETLYS/ETo in this study were also a linear function of the decrease in volumetric soil water content. The results indicate that even modest water stress can greatly reduce grapevine water use and that short-term measures of vine water status taken at midday are a reflection of daily grapevine water us
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