bluuebunny/crossref_metadata_2025_split huggingface dataset:
Vibration Calculation of Spatial Multibody Systems Based on Constraint-Topology Transformation
Authors: Jiang W. , Chen X. D. , Luo X. , Hu Y. T. , Hu H. P. 
Published: December 2011

ABSTRACTMany kinds of mechanical systems can be modeled as spatial rigid multibody systems (SR-MBS), which consist of a set of rigid bodies interconnected by joints, springs and dampers. Vibration calculation of SR-MBS is conventionally conducted by approximately linearizing the nonlinear equations of motion and constraint, which is very complicated and inconvenient for sensitivity analysis. A new algorithm based on constraint-topology transformation is presented to derive the oscillatory differential equations in three steps, that is, vibration equations for free SR-MBS are derived using Lagrangian method at first; then, an open-loop constraint matrix is derived to obtain the vibration equations for open-loop SR-MBS via quadric transformation; finally, a cut-joint constraint matrix is derived to obtain the vibration equations for closed-loop SR-MBS via quadric transformation. Through mentioned above, the vibration calculation can be significantly simplified and the sensitivity analysis can be conducted conveniently. The correctness of the proposed method has been verified by numerical experiments in comparison with the traditional approaches.
Postbuckling of Shape Memory Alloy Reinforced Cross-Ply and Angle-Ply Laminated Plates
Authors: Shiau L.-C. , Kuo S.-Y. , Chang S.-Y. 
Published: December 2011

ABSTRACTThe effect of shape memory alloy (SMA) on the postbuckling behavior of rectangular cross-ply and angle-ply plates by varying the SMA fiber spacing was investigated using the Finite Element Method. The formulation of the location-dependent linear, nonlinear stiffness matrices due to non-homogeneous material properties and the temperature-dependent recovery stress stiffness matrix were derived. Numerical results show that the increase of SMA fiber volume fraction and prestrain may generate more recovery stress, and increase the stiffness of SMA reinforced composite laminate. Therefore, the postbuckling deflections of the plate may be decreased significantly. The buckling mode that plate will buckle into is dependent on the fiber orientation of the angle-ply laminates. When the SMA fibers are concentrated in the center of the plate, the postbuckling deflections of the plate will be decreased considerably.
Thermal-Nonlocal Vibration and Instability of Single-Walled Carbon Nanotubes Conveying Fluid
Authors: Chang T.-P. 
Published: December 2011

ABSTRACTAn elastic Bernoulli–Euler beam model is developed for thermal-mechanical vibration and buckling instability of a single-walled carbon nanotube (SWCNT) conveying fluid and resting on an elastic medium by using the theories of thermal elasticity mechanics and nonlocal elasticity. The differential quadrature method is adopted to obtain the numerical solutions to the model. The effects of temperature change, nonlocal parameter and elastic medium constant on the vibration frequency and buckling instability of SWCNT conveying fluid are investigated. It can be concluded that at low or room temperature, the first natural frequency and critical flow velocity for the SWCNT increase as the temperature change increases, on the contrary, while at high temperature the first natural frequency and critical flow velocity decrease with the increase of the temperature change. The first natural frequency for the SWCNT decreases as the nonlocal parameter increases, both the first natural frequency and critical flow velocity increase with the increase of the elastic medium constant.
The Effects of Capacity Coupling and Wet Air Return on the Energy Performance of Chiller-Cooling Tower Systems
Authors: Liu C.-W. , Chuah Y.-K. 
Published: December 2011

ABSTRACTThis study uses a novel concept of capacity coupling of chiller-cooling tower system to investigate the system energy performance. System performance factor (SPF) of the chiller-cooling tower system is used in the analysis. A regression function is obtained for hourly reset of condensing water temperature so to achieve maximum SPF. The regression function includes parameters such as ambient wet bulb temperature, chiller load ratio, tower capacity ratio, and a dimensionless relative efficiency of chiller and cooling tower. The regression function has an R2 close to 1 compared to the computed results. It is found that for capacity coupling ratio of 1.1 ∼ 1.6, SPF would increase by about 3 ∼ 6% compared with a typical base control. The effect of wet air return is presented as an equivalent wet bulb temperature. It has been found that SPF would decrease significantly when higher equivalent wet bulb temperature occurs at the tower inlet.
The climatic environment of the Outer Hebrides
Authors: Manley Gordon 
Published: December 2011

SynopsisThe unsettled cool-maritime climate of the Outer Hebrides represents an extreme modification of that of the British Isles generally; yet while it imposes strains, as an environment for man it has long been far from unproductive. Frequency of rain as showers, wind, high humidity and slow evaporation provide difficulties; but there is a relatively long, if slow, growing season ending in a mild autumn. Results of instrumental observations over 120 years are discussed; trends are compared, but closer analysis is hampered by changes in location of station. Some indication of extent of gain from increased shelter is given.
Observations on the soils of the Outer Hebrides
Authors: Glentworth R. 
Published: December 2011

SynopsisThe distribution of soil parent materials in relation to glaciological features is dealt with; from the scoured bare rock of Harris products of Tertiary weathering have been transported northwards and deposited as coarse textured till which underlies the Lewis till plain. Clayey till in the north of Lewis would appear to be deposited by mainland ice which crossed the area. The dominant genetic soil found throughout the islands is a peaty podzol with iron pan which contains an intensely indurated horizon. Peat formation has developed on this soil as a result of the acidity of the parent material and anaerobic waterlogged conditions. Only on well sloping sites were peaty podzol soils with free drainage beneath the pan observed, otherwise the peaty podzol with very poor drainage beneath the pan is better described as a peaty gley soil. Brown earth soils were seen only on ultra-basic rocks on markedly sloping sites.As a result of exposure and frequent high winds the calcareous dunes of the machair are unstable. Fresh sand is deposited on the dry back slopes with a diluent effect on soil fertility. Areas of the machair having imperfect rather than poor drainage provide some of the best arable land which would be rated as Class 3 in the Land Use Capability Classification of the Soil Survey.
The polychaetes of Lewis and Harris with notes on other marine invertebrates
Authors: George J. D. 
Published: December 2011

SynopsisIn July 1976 six rocky littoral sites and eight rocky sublittoral sites in Lewis and Harris were sampled for polychaetes. The sites ranged from those on the exposed west and north coast to more sheltered east coast sites.A total of 107 species were recorded during the survey and are presented in an annotated species list. Syllidae are the dominant family both in number of species and number of individuals present, although the Serpulidae, Spionidae and Sabellidae are also well represented. Similarity of habitats sampled at different sites makes it possible to relate differences in species composition to the conditions prevailing at these localities. Such comparisons are made for four habitats—Corallina officinalis, sediment under stones on the shore, Laminaria holdfasts and the upper shell valves of Pecten. Twenty polychaete species were found in the C. officinalis habitat, 24 species in sediment under stones on the shore, 61 species in laminarian holdfasts and 22 species on the upper shell valves of Pecten.In general the sublittoral macroinvertebrate fauna, although lacking the Lusitanian elements found in the warmer waters of south-west England and Ireland, was found to have a high species diversity and to exist in an environment virtually free from man-made pollution.
Phytogeographical and ecological relations of epiphytic lichens from Lewis and Harris with notes on other cryptogamic epiphytes
Authors: Riedl Harald 
Published: December 2011

SynopsisFifty-eight epiphytic lichen species are listed from Lewis and Harris, and their geographical connections are discussed. Twenty-nine of them were collected on this island for the first time. Judging from the occurrence of Lecanactis homalotropa, Pyrenula laevigata and Ramalina obtusata (which are confined to very few places in the British Isles today and may be regarded as relics) on a small number of old and mostly dying sycamores near Rodel at the southern end of Harris, there had been an older forest of which these trees form the last remnants and from which the colonization of Stornoway Woods may have originated. Some of the lichens also occur on dwarf-shrubs which have certainly been present all the time, or on rocks or ground. Man may have played a part in introducing lichen-species along with timber. A few notes on epiphytic algae, fungi, mosses and ferns are added.
Macrophytic vegetation of fresh and brackish waters in and near the Loch Druidibeg National Nature Reserve, South Uist
Authors: Spence D. H. N. , Allen E. D. , Fraser J. 
Published: December 2011

SynopsisCentred on Loch Druidibeg, macrophyte vegetation was surveyed in and around 30 lochs in northern South Uist. Alkalinity ranges from 0·014 to 2·33 m.-equiv −1, conductivity (25°C) from 100 to 33,900 μs cm−1, chlorinity from 0·66 m.-equiv −1 upwards. Lochs are classed broadly as non-calcareous (gneissic), calcareous (machair) and brackish. This is an example of a Hebridean range not found elsewhere in the British Isles. Fen vegetation is highly modified by grazing, whilst tall reedswamp and floating-leaved plants are scarce on the mainly exposed and rocky shores, factors which contribute to the predominance of Fucoids in brackish water, of the open Littorella-Lobelia association in non-calcareous water. The Potamogeton filiformis-Chara association is confined to sand in calcareous machair lochs. Deep freshwater vegetation is typified by Isoetes, Potamogeton perfoliatus and P. praelongus.The very wide ranges in alkalinity and conductivity are reflected in some unusual species' distributions. For example, in freshwater lochs (conductivity up to 660 μs cm−1) several species like Isoetes lacustris, confined elsewhere to oligotrophic water, also occur in South Uist at moderately high alkalinities (to 1·8 m. -equiv 1−1). Conductivity varies with chloride concentration in all but the calcareous (machair) lochs; brackish lochs range from 2500 μs cm −1), which floristically, apart from Fucus ceranoides, is fresh water, to Fucoid-dominated rocks, and Ruppia on silt, in conductivities up to 33,900 μs cm−1. Of other angiosperms, Potamogeton gramineus appears to tolerate conductivities of 22,000 μs cm −1. Causal distribution in general is discussed.
Underwater glider observations and modeling of an abrupt mixing event in the upper ocean
Authors: Ruiz Simón , Renault Lionel , Garau Bartolomé , Tintoré Joaquín 
Published: December 2011

An abrupt mixing event in the upper ocean is investigated in the Northwestern Mediterranean Sea using gliders, a new ocean monitoring technology, combined with regional atmospheric model outputs and mooring data. Intense winds (up to 20 m s−1) and buoyancy forcing during December 2009 induced strong vertical mixing of the upper ocean layer in the Balearic Sea. High‐resolution data from a coastal glider reveal a surface cooling of near 2 °C and the deepening of the Mixed Layer Depth (MLD) by more than 40 meters in the center of the basin. Comparisons between glider and ship‐emulated sections of hydrographic profiles show that the glider data make visible the small‐scale spatial variability of the MLD. The heat content released to the atmosphere by the upper ocean during this mixing event exceeds 1000 W m−2. A simulation from the Weather Research and Forecasting model reports values consistent with these observations. Additionally the atmospheric numerical simulation shows the development and evolution of a cyclone located south of the Balearic Islands. This cyclone is likely to be responsible for the wind intensification and the consequent air‐sea energy exchanges that occurred in the study area during this period.
Forecasting the number of extreme daily events on seasonal timescales
Authors: Hamilton Emily , Eade Rosie , Graham Richard J. , Scaife Adam A. , Smith Doug M. , Maidens Anna , MacLachlan Craig 
Published: December 2011

We investigate the potential for skillfully predicting the number of daily temperature extremes over 3 month (seasonal) periods. We use retrospective forecasts from the Met Office seasonal forecasting system, GloSea4, nominally initialized 1 month ahead of the target season. Initially, we define daily extremes to be events outside either the upper or lower deciles of the daily temperature distribution from the relevant season. This definition provides a threshold that is sufficiently “extreme” to be of interest to many users but moderate enough to allow a sufficient sample for verification and to be of regular use to users. We show that skill reduces slightly at more extreme thresholds. Correlations of predicted and observed numbers of upper or lower decile extreme days over a season are significantly greater than zero over much of the globe and, in general, are better than a persistence forecast. Forecast skill for seasonal mean temperature is similar to, but generally greater than, the skill of predictions of the number of extreme days. Observations have a strong relationship between the seasonal mean and the number of extreme days. We show that the skill in predicting the number of extreme days is largely a consequence of this relationship and occurs primarily through a shift in the distribution of the daily data rather than a change of its shape. The ability to predict the El Niño–Southern Oscillation and climate change are both significant contributors to the skill in predicting temperature extremes. In summer, significant skill also comes from initializing soil moisture.
Variations in diurnal temperature range over India: Under global warming scenario
Authors: Rai Archana , Joshi Manish K. , Pandey A. C. 
Published: December 2011

Annual, seasonal, and monthly trends in surface air temperature were examined over India during the period 1901–2003. Besides this, annual and seasonal trends were also scrutinized in view of global warming concerns during the 2 non‐global (1901–1909 and 1946–1975) and global (1910–1945 and 1976–2003) warming periods as defined by Intergovernmental Panel on Climate Change. A significant increasing trend of 0.743, 0.224, 0.484, and 0.52°C (100 yr)−1 has been observed in maximum (Tmax), minimum (Tmin), mean (Tmean) temperatures, and diurnal temperature range (DTR; Tmax − Tmin), respectively during the period 1901–2003. The annual temperatures (Tmean, Tmin, and Tmax) show a cooling (warming) tendency during the non‐global (global) warming periods, apart from the second non‐global warming period ofTmax. The seasonal trends in Tmin and Tmean also show similar behavior; whereas, Tmaxshows warming in all sub‐periods, excluding the first non‐global warming period of the pre‐monsoon and monsoon. Seasonal analysis depicts that, both post‐monsoon and winter seasons are getting warmer with regard toTmax and Tmin. During the analysis as well as in non‐global and global warming periods, annualDTR has increased. DTRincreases in all seasons, with the largest increase in winter and the smallest in post‐monsoon; whereas monthly analysis reveals that all the months, except March, October, and November are contributing significantly to the annual increase ofDTR. The partial correlation analysis reveals that the total cloud cover along with the secondary factors like precipitation and soil‐moisture are responsible for increase inDTR over India during the period 1948–2003.
Family values: Maternal care in rattlesnakes is more than mere attendance
Authors: Amarello Melissa , Smith Jeffrey , Slone John 
Published: December 2011

AbstractParental care is important in many diverse taxa because of its positive impact on the parent's fitness. Relatively simple forms of parental care, such as female attendance and defense, which is present in many squamate reptiles, will likely provide insight into the evolution of more complex forms observed in crocodilians, birds, and mammals. Historically, observations of adult and newborn rattlesnakes in close proximity were dismissed as mere coincidence of live-birth, and only recently acknowledged as examples of parental care. In 2010, we monitored 11 pregnant Arizona black rattlesnakes (Crotalus cerberus): 4 solitary individuals and 2 aggregations composed of three and four individuals. We documented various forms of parental care, including active defense of neonates against potential predators. Parental care differed among solitary and aggregated females; solitary females spent more time attending and defending their progeny than individuals in aggregations. Natural variation in group size in C. cerberus provides an ancestral condition in which to examine how group membership may increase fitness through parental care.
Differential expression of LeY and fucosyltransferase IV correlates with the receptivity of RL95‐2 and HEC‐1A human uterine epithelial cells
Authors: Liu Shuai , Yang Xuesong , Wang Jiao , Wei Jianxin , Zhang Dongmei , Wang Xiaoqi , Yan Qiu 
Published: December 2011

AbstractAdhesion molecules expressed on the uterine endometrium are potential receptive markers in embryo implantation. RL95‐2 and HEC‐1A cell lines represent the high‐ and low‐receptive endometrial epithelium respectively. LeY (Lewis Y) is a difucosylated oligosaccharide highly expressed in the endometrium of some species during implantation. α1, 3 fucosylation of LeY is catalysed by FUT4 (fucosyltransferase IV), the key synthesis enzyme for LeY. We investigated whether the difference in receptivity between the 2 cell lines was related to different expressions of LeY and FUT4. RL95‐2 cells expressed a higher level of LeY and FUT4 than HEC‐1A cells, as shown by immunofluorescent staining, RT—PCR (reverse transcription—PCR) or Western blotting. FUT4‐siRNA (small interfering RNA) transfection down‐regulated FUT4 and LeY in RL95‐2 cells, and inhibited the adhesion of the embryonic cells (JAR) to RL95‐2 cell monolayer. FUT4‐cDNA, however, increased the expression of FUT4 and LeY in HEC‐1A cells, and increased the adhesion of embryonic cells to HEC‐1A cell monolayer. Alterations of LeY level by up‐ or down‐regulation of FUT4 also mediated EGFR (epidermal growth factor receptor)/MAPK (mitogen‐activated protein kinase) signalling pathway. To conclude, the expression of LeY and FUT4 correlates with endometrial receptivity, making them potential new markers for the evaluation of endometrial receptivity.
Bias in macrophage activation pattern influences non-alcoholic steatohepatitis (NASH) in mice
Authors: Maina Virginia , Sutti Salvatore , Locatelli Irene , Vidali Matteo , Mombello Cristina , Bozzola Cristina , Albano Emanuele 
Published: December 2011

In humans, there is large inter-individual variability in the evolution of NAFLD (non-alcoholic fatty liver disease) to NASH (non-alcoholic steatohepatitis). To investigate this issue, NASH was induced with an MCD (methionine–choline-deficient) diet in C57BL/6 and Balb/c mice that are characterized by different biases in Th1/Th2 and macrophage (M1/M2) responses. Following 4 weeks on the MCD diet, steatosis and lobular inflammation were prevalent in C57BL/6 (Th1, M1 oriented) than in Balb/c (Th2, M2 oriented) mice. Consistently, hepatic TNFα (tumour necrosis factor α) mRNA expression and circulating TNFα levels were higher in MCD-fed C57BL/6 than in MCD-fed Balb/c mice. The Th1/Th2 bias did not account for the increased NASH severity, as in both strains MCD feeding did not significantly modify the liver mRNA expression of the Th1 markers IFNγ (interferon γ) and T-bet or that of the Th2 markers IL-4 (interleukin 4) and GATA-3. Conversely, MCD-fed C57BL/6 mice displayed higher liver mRNAs for the macrophage M1 activation markers iNOS (inducible NO synthase), IL-12p40 and CXCL10 (CXC chemokine ligand 10) than similarly treated Balb/c mice, without effects on the M2 polarization markers IL-10 and MGL-1 (macrophage galactose-type C-type lectin-1). Circulating IL-12 was also higher in MCD-fed C57BL/6 than in MCD-fed Balb/c mice. The analysis of macrophages isolated from the livers of MCD-fed animals confirmed an enhanced expression of M1 markers in C57BL/6 mice. Among all of the MCD-treated mice, liver iNOS, IL-12p40 and CXCL10 mRNA levels positively correlated with the frequency of hepatic necro-inflammatory foci. We concluded that the macrophage M1 bias in C57BL/6 mice may account for the increased severity of NASH in this strain, suggesting macrophage responses as important contributors to NAFLD progression.
Is Measured Hearing Aid Benefit Affected by Seeing Baseline Outcome Questionnaire Responses?
Authors: Silverman ShienPei , Cates Megan , Saunders Gabrielle 
Published: December 2011

PurposeTo determine whether hearing aid outcome measured by the Hearing Handicap Inventory (HHI) for the Elderly/Adults (Newman, Weinstein, Jacobson, & Hug, 1990; Ventry & Weinstein, 1982) is differentially affected by informed vs. blind administration of the postfitting questionnaire.MethodParticipants completed the HHI at their hearing aid evaluation and again at their hearing aid follow-up visit. At follow-up, half received a clean HHI form (blind administration), whereas the remainder responded on their original form (informed administration) and could thus base their follow-up responses on those they gave at the hearing aid evaluation.ResultsThe data show that for the population examined here, informed administration of the follow-up HHI did not yield a different outcome to blind administration of the follow-up HHI. This was not influenced by past hearing aid use, age of the participant, or the duration of time between baseline questionnaire completion and follow-up completion.ConclusionThese data suggest that completion of follow-up questionnaires in either informed or blind format will have little impact on HHI responses, most likely because of the many other factors that combined to influence hearing aid outcome.
Effects of Transient Noise Reduction Algorithms on Speech Intelligibility and Ratings of Hearing Aid Users
Authors: DiGiovanni Jeffrey J. , Davlin Erin A. , Nagaraj Naveen K. 
Published: December 2011

PurposeThe goal of this study was to assess the functional utility of transient noise reduction (TNR) algorithms available in hearing aids via speech intelligibility and user preferences.MethodTwo pairs of hearing aids, 1 pair each from Siemens and Unitron, were programmed for 17 hearing impaired individuals after a hearing evaluation. Intelligibility was measured for each participant for sentences presented in quiet, with 2 types of transient noise, multitalker babble, and in a combination of each type of transient noise and multitalker babble. Each condition was tested with TNR activated and TNR deactivated in a counterbalanced, single-blinded format. Subjective ratings of overall speech understanding, comfort, and sound quality were obtained for each condition.ResultsA significant improvement in speech intelligibility was measured with the TNR activated when speech was presented in multitalker babble, in the presence of chair clang transient noises, and when combining these noises. Activation of the TNR algorithm did not result in significant improvements for any of the subjective ratings.ConclusionsWhile improvements were limited to certain conditions, specifically those with the chair clang transient and/or multitalker babble, TNR appears to offer an incremental step in improving the listening experience for hearing aid users.