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Insomnia and depression are highly comorbid and mutually exacerbate clinical trajectories and outcomes. Cognitive behavioral therapy for insomnia (CBT-I) effectively reduces both insomnia and depression severity, and can be delivered digitally. This could substantially increase the accessibility to CBT-I, which could reduce the health disparities related to insomnia; however, the efficacy of digital CBT-I (dCBT-I) across a range of demographic groups has not yet been adequately examined. This randomized placebo-controlled trial examined the efficacy of dCBT-I in reducing both insomnia and depression across a wide range of demographic groups.
Of 1358 individuals with insomnia randomized, a final sample of 358 were retained in the dCBT-I condition and 300 in the online sleep education condition. Severity of insomnia and depression was examined as a dependent variable. Race, socioeconomic status (SES; household income and education), gender, and age were also tested as independent moderators of treatment effects.
The dCBT-I condition yielded greater reductions in both insomnia and depression severity than sleep education, with significantly higher rates of remission following treatment. Demographic variables (i.e. income, race, sex, age, education) were not significant moderators of the treatment effects, suggesting that dCBT-I is comparably efficacious across a wide range of demographic groups. Furthermore, while differences in attrition were found based on SES, attrition did not differ between white and black participants.
Results provide evidence that the wide dissemination of dCBT-I may effectively target both insomnia and comorbid depression across a wide spectrum of the population.
Modern datasets provide the context necessary for accurate interpretations of isotopic data from archaeological faunal assemblages. In this study, we use the oxygen isotope ratios (δ18O) of modern small mammals from Chaco Canyon, New Mexico, to quantify expected isotopic variation in a local population. The δ18O values of local, modern small mammals encompass a broad range (−6.0‰ to 4.8‰ VPDB), which is expected given the extreme seasonal variation in the δ18O of precipitation on the Colorado Plateau (−11‰ to −3‰ VPDB). Isotopic ratios of small mammals obtained from excavated archaeological sites in Chaco Canyon (ca. AD 800 to 1200) show no significant differences with their modern counterparts, suggesting that there is no difference in the origins of the archaeological small-mammal collection and the modern, local Chaco Canyon small-mammal collection. In contrast, δ18O values of large mammals from Chaco archaeological sites are significantly different from those of modern specimens, reflecting a nonlocal, but also nonspecific, source in the past.
Previous studies have suggested that a high intake of sugar-sweetened beverages is positively associated with the risk of a coronary event. However, a few studies have examined the association between sucrose (the most common extrinsic sugar in Sweden) and incident coronary events. The objective of the present study was to examine the associations between sucrose intake and coronary event risk and to determine whether these associations are specific to certain subgroups of the population (i.e. according to physical activity, obesity status, educational level, alcohol consumption, smoking habits, intake of fat and intake of fruits and vegetables). We performed a prospective analysis on 26 190 individuals (62 % women) free from diabetes and without a history of CVD from the Swedish population-based Malmö Diet and Cancer cohort. Over an average of 17 years of follow-up (457 131 person-years), 2493 incident cases of coronary events were identified. Sucrose intake was obtained from an interview-based diet history method, including 7-d records of prepared meals and cold beverages and a 168-item diet questionnaire covering other foods. Participants who consumed >15 % of their energy intake (E%) from sucrose showed a 37 (95 % CI 13, 66) % increased risk of a coronary event compared with the lowest sucrose consumers (<5 E%) after adjusting for potential confounders. The association was not modified by the selected lifestyle factors. The results indicated that sucrose consumption higher than 15 E% (5 % of this population) is associated with an increased risk of a coronary event.
To characterize meal patterns across ten European countries participating in the European Prospective Investigation into Cancer and Nutrition (EPIC) calibration study.
Cross-sectional study utilizing dietary data collected through a standardized 24 h diet recall during 1995–2000. Eleven predefined intake occasions across a 24 h period were assessed during the interview. In the present descriptive report, meal patterns were analysed in terms of daily number of intake occasions, the proportion reporting each intake occasion and the energy contributions from each intake occasion.
Twenty-seven centres across ten European countries.
Women (64 %) and men (36 %) aged 35–74 years (n 36 020).
Pronounced differences in meal patterns emerged both across centres within the same country and across different countries, with a trend for fewer intake occasions per day in Mediterranean countries compared with central and northern Europe. Differences were also found for daily energy intake provided by lunch, with 38–43 % for women and 41–45 % for men within Mediterranean countries compared with 16–27 % for women and 20–26 % for men in central and northern European countries. Likewise, a south–north gradient was found for daily energy intake from snacks, with 13–20 % (women) and 10–17 % (men) in Mediterranean countries compared with 24–34 % (women) and 23–35 % (men) in central/northern Europe.
We found distinct differences in meal patterns with marked diversity for intake frequency and lunch and snack consumption between Mediterranean and central/northern European countries. Monitoring of meal patterns across various cultures and populations could provide critical context to the research efforts to characterize relationships between dietary intake and health.
Professor Colomb resigned as President of the Commission because of pressing demands of work. The Organizing Committee appointed Stuart Bowyer (Vice President) as Acting President.
The Commission has proposed changing its name to “Bioastronomy: Search for Extrasolar Planets and Extraterrestial Life” to reflect our long-standing involvement in the search for extrasolar planets. The name change is pending approval of the IAU.
This report summarises the work of the third season of the Fezzan project which took place in January 1999. The main environmental findings of the project team of specialist geographers are providing confirmation of dramatic climatic and environmental change over the last 100,000 years and give more precise dates for some of these changes. The excavations in Old Germa (ancient Garama) have continued through Islamic levels, with elements of five main phases of buildings now having been recorded. Additional standing structures, including one of Germa's main mosques, have been surveyed. Field survey around Germa has revealed further new settlement sites of prehistoric, Garamantian and Islamic date. Of particular importance is a series of lithic and pottery scatters relating to neolithic occupation along the edge of the Ubari Sand Sea, to the north of Germa. Further investigation of the irrigation channels (foggaras) has revealed significant new information about their size, construction and probable date. The report concludes with a brief preliminary analysis of changing settlement patterns over time.
The fourth season of the Fezzan Project continued the interdisciplinary approaches of previous seasons. Geographical and environmental work focused principally in sampling sediments for scientific dating and with integrating ground observation with remote sensing data. Excavations continued at Old Germa, where the site has now reached Garamantian levels. In a separate development, the tentative identification has been made of an early mosque at the site, in an area adjacent to the G1 excavation trench. Substantial results were gained from work aimed at enhancing the important data recorded by Charles Daniels in his earlier excavations and survey in the Wadi al-Hayat. The enhancement of the Daniels' survey archive was integrated with completion of the wider prospection being undertaken by the new project. This survey included fieldwalking, standing building survey, analysis of the foggara irrigation systems and recording of rock art scenes. Finds work comprised the finalisation of a pottery type series for the Germa area, the study of small finds from the recent survey work, botanical analysis and completion of lithics recording. A programme of radiocarbon dating is now being undertaken to improve the phasing of sites and monuments. The first two volumes of final reports are now in preparation.
The Fezzan Project completed its five-year fieldwork cycle in 2001. The geographical research team located numerous additional palaeolake sites within the Edeyen Ubari, using a combination of Remote Sensing technology and field visits. Additional samples were taken for analysis and dating from many lake edge locations, relating to both the large Pleistocene lake and to the numerous smaller Holocene lakes that have been identified by the team. The excavations at Old Germa were taken down through Garamantian occupation levels to the natural subsoil below the earliest cultural horizon. The earliest activity, represented by a few mudbrick walls and hearths built directly on the natural soil, is believed to date to c. 400-300 BC. Traces of several phases of Garamantian buildings were uncovered, along with numerous rubbish pits, which yielded a rich assemblage of finds, including, for the first time, examples of Garamantian figurines, small 3-D sculptures of humans and animals. Work on the various classes of finds (pottery, small finds, lithics and other stone artefacts, metallurgical evidence, etc.) complemented the excavation work. In addition, a small amount of further survey work was carried out on sites in the Wadi al-Ajal, along with a contour survey of Old Germa and standing building survey at a number of other sites.
The characteristics of unbounded flow past an impulsively started planar energy extracting device, such as a wind or tidal turbine, are studied theoretically, numerically and experimentally. The initial thrust on an impulsively started device, which can be more than double the steady thrust, is an important consideration for design and safe operation. The energy sink is modelled here as an ‘actuator surface’ which imposes a uniform pressure discontinuity in the fluid proportional to the square of the fluid speed normal to the surface, the fluid density, and a dimensionless resistance coefficient. The flow past the actuator is studied theoretically for the case of weak resistance using an unsteady model which recovers steady linear momentum theory in the limit of long time. For the case of strong resistance the flow is studied numerically using the point vortex method. Experimental measurements of thrust on a mesh towed through static water are compared to the numerical results and show good agreement. The thrust on an impulsively started device is estimated, for a typical installation, to fall to within 10 % of the steady value within ∼1 min. The numerical model is also used to simulate the gradual startup of a device, yielding estimates of the time constant necessary in a control system in order to reduce peak thrusts in practice.
X-ray specular and off-specular reflectivity studies have been carried out to study the density modulations in liquids confined between two smooth silicon mirrors. The special technique as well as the advantages of using high energy and high brilliance synchrotron x-ray beams for carrying out such experiments will be discussed. Results will be presented on the ordering of octamethyl-cyclotetrasiloxane (OMCTS) as a function of the confining pressure, where we find evidence of layering as the gap is decreased from macroscopic down to a few nanometers.
In this work a newly developed dual control volume grand canonical molecular dynamics technique simulates the diffusion of gas in a cylindrical pore. This allows spatial variation of chemical potential and hence an accurate simulation of steady state pressure driven diffusion. The molecular sieving nature of imicroporous imogolite models and the Knudsen effect are discussed and compared with experimental data.
We report here on the application of the new technique of the X-Ray Surface Forces Apparatus (XSFA) to the study of the smectic liquid crystal 8CB (4-cyano-4′-octylbiphenyl) and a zwitterionic polyisoprene melt. The XSFA allows one to study the structure of fluid films under confinement and flow using intense synchrotron x-ray radiation. The above systems were investigated with the distances between the confining surfaces ranging from 0.4μm to a few tens of microns. Two different kinds of confining surfaces were used leading to different structural behavior of the samples as a function of the confining gap.
We describe the influence of local magnetization on electron localization and transport properties on the insulating side of the metal insulator transition in the dilute magnetic persistent photoconductor Cd0.091 Mn0.09Te:ln. Measurements of both the temperature dependence of the transport properties, and also the dielectric constant, are reported for just one sample in which the carrier concentration n was varied by photodoping. From these results we are able to extract the carrier concentration dependence of the localization length and the permitivity of the electrons. We also report onl a new transport effect which occurs at ultra low temperatures and/or carrier concentrations very close to the metal insulator transition. We find that this mechanism is totally magnetic in origin and are able to explain it in terms of the well devewloped ideas of magnetic polarons in magnetic semiconductors.
The kinetics of de-wetting a polycarbonate (PC) film from a poly(styrene-coacrylonitrile) (SAN) copolymer film was monitored using optical microscopy. Whereas the SAN layer was stable upon annealing at 190°C, the PC layer dewetted the SAN and formed holes whose diameter increased linearly with time. Auger electron spectroscopy measurements confirmed that PC was fully removed from the interior of the hole. Upon varying the AN content, the dewetting velocity was found to be a minimum near 0.27 weight percent AN. This result is consistent with the interfacial thermodynamics between PC and SAN. Atomic force microscopy was used to provide a unique image of the hole profile.
In this work we simulate the diffusion of gases in a microporous solid models using a newly developed dual control volume grand canonical molecular dynamics technique. This allows spatial variation of chemical potential and hence an accurate simulation of steady-state pressure driven diffusion. The molecular sieving nature of microporous zeolites are discussed and compared with that for amorphous silica from sol-gel methods. Massively parallel supercomputers allow a quick and insightful study of these microporous structures.
We report a light-induced, surface-assisted structural phase transition from a common orthorhombic phase of crystalline gallium (α-gallium) to a highly reflective, metastable phase of more ‘metallic’ nature. The transition has been observed at the interface of gallium with fused silica at temperatures just below the metal's bulk melting point and affects only several tens of gallium atomic layers. The transition is fully reversible and occurs on a nanosecond/microsecond time scale. The transition appears to show some characteristic features of a second order structural phase transition, including an increase of the transition relaxation times at the critical temperature (of approximately 30°C). The transition has no apparent optical intensity threshold, and is induced by radiation of very low intensity of only 10−4 − 10−5 W/μm2. The two gallium phases involved in the phase transition have significantly different dielectric properties which gives rise to a gigantic cubic optical nonlinearity, χ(3) ∼ 1 esu. The transition can be stimulated by light at any wavelength in the visible and the infrared ranges out to at least 1.55μm. The effect is therefore of great interest for applications requiring light by light control at milliwatt power levels.
Despite the large body of research concerned with the near wake of a circular cylinder, the far wake, which extends beyond about 100 diameters downstream, is relatively unexplored, especially at low Reynolds numbers. We have recently shown that the structure of the far wake is exquisitely sensitive to free-stream noise, and is precisely dependent on the frequency and scale of the near wake; indeed it is shown that the presence of extremely low-amplitude peaks in the free-stream spectrum, over a remarkably wide range of frequencies, are sufficient to trigger an “oblique wave resonance” in the far wake.
We show, in the upper photograph of Fig. 1, a nonlinear interaction between oblique shedding waves generated from upstream (to the left) and 2–D waves amplified downstream from free-stream disturbances (in the central region). We use the “smoke-wire” technique (placed 50 diameters down-stream), and the wake is viewed in planview, with flow to the right. This two-wave interaction triggers a third wave, namely an “oblique resonance wave” at a large oblique angle, to grow through nonlinear effects (in the right half of the photograph), in preference to the original two waves. If smoke is introduced 100 diameters downstream, in the lower photograph (under slightly different conditions), then all that is seen is a set of such large-angle oblique resonance waves.
This work is supported by the Office of Naval Research.
Visualization of different transition mechanisms
The sequence of photos in Figs. 1(a)-1(d) illustrates the different types of boundary-layer transitions that occur as a function of Tollmien-Schlichting (T-S) wave amplitude and fetch.
Spontaneous localised propagating waves of contraction and localised stretches have been reported to occur in the isolated whole bladder of the guinea pig. The physiological role and the cellular processes underlying these events are unknown. In order to gain insight into the mechanisms generating this complex activity, experiments were performed to examine and compare the responses of the whole bladder preparation to (i) the muscarinic agonists carbachol and arecaidine, (ii) the nicotinic ligand lobeline and (iii) nerve stimulation. High concentrations of the muscarinic agonists (>3 µM) induced a slow rise in intra-vesical pressure upon which were superimposed pressure transients, while low concentrations (< 300 nM) induced only phasic rises in pressure. One interpretation of these data is that there are two separate mechanisms activated by muscarinic agonists: one generating contracture and the other phasic activity. Immunocytochemical staining revealed M3 muscarinic receptors on smooth muscle cells within trabeculae and a second population of positive cells in the sub-urothelial layer. This observation raises the possibility that the actions of muscarinic agonists are a consequence of activating different cell types. Lobeline (1-60 µM) activated phasic contractions but did not cause a rise in basal pressure. Atropine did not inhibit the lobeline-induced responses but abolished the muscarinic responses. Also, hexamethonium or tetrodotoxin did not affect the lobeline-induced responses. These observations suggest that the mechanism generating phasic activity is activated by a nicotinic stimulus that does not involve ganglia, nerves or the neuromuscular junction. Stimulation of the bladder nerve at frequencies between 20 and 30 Hz for 5 s resulted in a rapid rise in intra-vesical pressure. Prolonged nerve stimulation (10-200 s) at frequencies between 1 and 10 Hz activated phasic rises in pressure. Low frequency nerve stimulation increased the frequency of agonist-induced phasic activity. Thus, nerve stimulation can also produce two forms of activity and low frequency stimulation can augment the processes generating phasic activity. These observations suggest that there are two distinct types of bladder activity: global contractions involving most of the bladder wall and phasic contractions comprising propagating waves of contraction. The mechanisms generating these contractile events appear to be different and they may involve cells located in different regions of the bladder. The nature of these mechanisms and their possible physiological significance is discussed. Experimental Physiology (2003) 88.3, 343-357.
Phasic changes in pressure have been reported to occur in the bladder which are not associated with micturition. Spontaneous intravesical pressure changes can be recorded from bladders in vitro or bladders in vivo isolated from the central nervous system suggesting that the bladder itself is capable of autonomous activity. Experiments using isolated cells and muscle strips indicate that the smooth muscle can generate spontaneous activity. Whether this is the origin of phasic changes in the intact organ remains unknown. The present study set out to establish the presence and characteristics of autonomous activity in the isolated guinea pig bladder. Multiple-point motion analysis and concurrent intravesical pressure recording were used to identify and quantify spontaneous and evoked activity. Highly complex autonomous activity was observed in unstimulated bladders. This activity comprised localised micro-contractions in single or multiple discrete regions, waves of activity and micro-stretches. Low-amplitude phasic 'micro-transients' were seen in the intravesical pressure trace in association with micro-contractions. Incremental increases in the intravesical volume recruited additional areas of activity. Atropine and tetrodotoxin had no effect on the micro-transients or micro-contractions. Exposure to the muscarinic agonist arecaidine (10-300 nM) initially increased the incidence of micro-contractions which subsequently became co-ordinated into phasic pressure rises and contraction waves, interspersed with periods of total quiescence. The findings describe the generation and co-ordination of autonomous activity in the bladder wall and also demonstrate complex phasic activity. This approach has shown the importance of assessing the integrative properties of the entire organ in studies of the physiology and patho-physiology of the bladder. Experimental Physiology (2003) 88.1, 19-30.