Seamless Tube-Type Heater with Uniform Thickness and Temperature Distribution Based on Carbon Nanotubes Aligned by Circumferential Shearing

The uniform temperature distribution, one of the requirements for long-term durability, is essential for composite heaters. An analytical model for temperature distribution of a tube-type heater was derived, and it revealed that thickness uniformity is one order more important than intrinsic material properties such as density, heat capacity, and electrical conductivity of the heating tube. We introduced a circumferential shearing process to fabricate a flexible, seamless tube-type heating layer of carbon nanotube/silicone rubber composite with outstanding uniform distribution of thickness and temperature, which may be attributed to a shorter characteristic dimension in the circumferential direction than in the axial direction. The temperature uniformity was experimentally verified at various temperatures under heating. The difference in measured thickness and temperature in circumferential direction was within ±1.3~3.0% (for tavg = 352.7 μm) and ±1.1% (for Tavg = 138.8 °C), respectively, all over the heating tube. Therefore, the circumferential shearing process can be effective for cylindrical heaters, like a heating layer of a laser printer, which fuse toners onto papers during printing.

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A Problem of Long - Term Digital Preservation: Difference in Humanities and Natural Sciences

Bibliotheca Lituana ◽

10.15388/bibllita.2014.3.15570 ◽

2014 ◽

Vol 3 ◽

pp. 183-195

Author(s):

Elena Macevičiūtė

Keyword(s):

Social Sciences ◽

Digital Preservation ◽

Dynamic Activity ◽

Private Companies ◽

Time Line ◽

Digital Documents ◽

Whole Process ◽

The Difference ◽

Technological Science

The article deals with the requirements and needs for long-term digital preservation in different areas of scholarly work. The concept of long-term digital preservation is introduced by comparing it to digitization and archiving concepts and defined with the emphasis on dynamic activity within a certain time line. The structure of digital preservation is presented with regard to the elements of the activity as understood in Activity Theory. The life-cycle of digitization processes forms the basis of the main processing of preserved data in preservation archival system.The author draws on the differences between humanities and social sciences on one hand and natural and technological science on the other. The empirical data characterizing the needs for digital preservation within different areas of scholarship are presented and show the difference in approaches to long-term digital preservation, as well as differences in selecting the items and implementing the projects of digital preservation. Institutions and organizations can also develop different understanding of preservation requirements for digital documents and other objects.The final part of the paper is devoted to some general problems pertaining to the longterm digital preservation with the emphasis of the responsibility for the whole process of safe-guarding the cultural and scholarly heritage for the re-use of the posterior generations. It is suggested that the longevity of the libraries in comparison with much shorter life-span of private companies strengthens the claim of memory institutions to playing the central role in the long-term digital preservation.

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CSO Modelling Considering Moving Storms and Tipping Bucket Gauge Failures

Water Practice & Technology ◽

10.2166/wpt.2007.024 ◽

2007 ◽

Vol 2 (1) ◽

Cited By ~ 1

Author(s):

M. Hochedlinger ◽

W. Sprung ◽

H. Kainz ◽

K. König

Keyword(s):

Hydrological Models ◽

Rain Intensity ◽

Hydrodynamic Models ◽

Data Intensive ◽

Storm Flow ◽

Cell Velocity ◽

Combined Sewer ◽

Moving Direction ◽

The Difference

The simulation of combined sewer overflow volumes and loads is important for the assessment of the overflow and overflow load to the receiving water to predict the hydraulic or the pollution impact. Hydrodynamic models are very data-intensive and time-consuming for long-term quality modelling. Hence, for long-term modelling, hydrological models are used to predict the storm flow in a fast way. However, in most cases, a constant rain intensity is used as load for the simulation, but in practice even for small catchments rain occurs in rain cells, which are not constant over the whole catchment area. This paper presents the results of quality modelling considering moving storms depending on the rain cell velocity and its moving direction. Additionally, tipping bucket gauge failures and different corrections are also taken into account. The results evidence the importance of these considerations for precipitation due the effects on overflow load and show the difference up to 28% of corrected and uncorrected data and of moving rain cells instead of constant raining intensities.

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Soil erosion by snow gliding – a first quantification attempt in a subalpine area in Switzerland

Hydrology and Earth System Sciences ◽

10.5194/hess-18-3763-2014 ◽

2014 ◽

Vol 18 (9) ◽

pp. 3763-3775 ◽

Cited By ~ 9

Author(s):

K. Meusburger ◽

G. Leitinger ◽

L. Mabit ◽

M. H. Mueller ◽

A. Walter ◽

...

Keyword(s):

Land Use ◽

Soil Erosion ◽

Land Cover ◽

Sediment Yield ◽

Soil Loss ◽

Water Erosion ◽

Erosion Rates ◽

The Difference ◽

Snow Gliding

Abstract. Snow processes might be one important driver of soil erosion in Alpine grasslands and thus the unknown variable when erosion modelling is attempted. The aim of this study is to assess the importance of snow gliding as a soil erosion agent for four different land use/land cover types in a subalpine area in Switzerland. We used three different approaches to estimate soil erosion rates: sediment yield measurements in snow glide depositions, the fallout radionuclide 137Cs and modelling with the Revised Universal Soil Loss Equation (RUSLE). RUSLE permits the evaluation of soil loss by water erosion, the 137Cs method integrates soil loss due to all erosion agents involved, and the measurement of snow glide deposition sediment yield can be directly related to snow-glide-induced erosion. Further, cumulative snow glide distance was measured for the sites in the winter of 2009/2010 and modelled for the surrounding area and long-term average winter precipitation (1959–2010) with the spatial snow glide model (SSGM). Measured snow glide distance confirmed the presence of snow gliding and ranged from 2 to 189 cm, with lower values on the north-facing slopes. We observed a reduction of snow glide distance with increasing surface roughness of the vegetation, which is an important information with respect to conservation planning and expected and ongoing land use changes in the Alps. Snow glide erosion estimated from the snow glide depositions was highly variable with values ranging from 0.03 to 22.9 t ha−1 yr−1 in the winter of 2012/2013. For sites affected by snow glide deposition, a mean erosion rate of 8.4 t ha−1 yr−1 was found. The difference in long-term erosion rates determined with RUSLE and 137Cs confirms the constant influence of snow-glide-induced erosion, since a large difference (lower proportion of water erosion compared to total net erosion) was observed for sites with high snow glide rates and vice versa. Moreover, the difference between RUSLE and 137Cs erosion rates was related to the measured snow glide distance (R2 = 0.64; p < 0.005) and to the snow deposition sediment yields (R2 = 0.39; p = 0.13). The SSGM reproduced the relative difference of the measured snow glide values under different land uses and land cover types. The resulting map highlighted the relevance of snow gliding for large parts of the investigated area. Based on these results, we conclude that snow gliding appears to be a crucial and non-negligible process impacting soil erosion patterns and magnitude in subalpine areas with similar topographic and climatic conditions.

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Stator Non-Uniform Radial Ventilation Design Methodology for a 15 MW Turbo-Synchronous Generator Based on Single Ventilation Duct Subsystem

Energies ◽

10.3390/en14102760 ◽

2021 ◽

Vol 14 (10) ◽

pp. 2760

Author(s):

Ruiye Li ◽

Peng Cheng ◽

Hai Lan ◽

Weili Li ◽

David Gerada ◽

...

Keyword(s):

Finite Element ◽

Temperature Distribution ◽

Design Methodology ◽

Large Scale ◽

Synchronous Generator ◽

Axial Direction ◽

Scale Model ◽

Element Analysis ◽

Axial Temperature ◽

Ventilation Duct

Within large turboalternators, the excessive local temperatures and spatially distributed temperature differences can accelerate the deterioration of electrical insulation as well as lead to deformation of components, which may cause major machine malfunctions. In order to homogenise the stator axial temperature distribution whilst reducing the maximum stator temperature, this paper presents a novel non-uniform radial ventilation ducts design methodology. To reduce the huge computational costs resulting from the large-scale model, the stator is decomposed into several single ventilation duct subsystems (SVDSs) along the axial direction, with each SVDS connected in series with the medium of the air gap flow rate. The calculation of electromagnetic and thermal performances within SVDS are completed by finite element method (FEM) and computational fluid dynamics (CFD), respectively. To improve the optimization efficiency, the radial basis function neural network (RBFNN) model is employed to approximate the finite element analysis, while the novel isometric sampling method (ISM) is designed to trade off the cost and accuracy of the process. It is found that the proposed methodology can provide optimal design schemes of SVDS with uniform axial temperature distribution, and the needed computation cost is markedly reduced. Finally, results based on a 15 MW turboalternator show that the peak temperature can be reduced by 7.3 ∘C (6.4%). The proposed methodology can be applied for the design and optimisation of electromagnetic-thermal coupling of other electrical machines with long axial dimensions.

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Malpigmentation of Common Sole (Solea solea) during Metamorphosis Is Associated with Differential Synaptic-Related Gene Expression

Animals ◽

10.3390/ani11082273 ◽

2021 ◽

Vol 11 (8) ◽

pp. 2273

Author(s):

Menelaos Kavouras ◽

Emmanouil E. Malandrakis ◽

Ewout Blom ◽

Kyriaki Tsilika ◽

Theodoros Danis ◽

...

Keyword(s):

Gene Expression ◽

Nervous System ◽

De Novo ◽

Close Association ◽

Ionic Channels ◽

Long Term Potentiation ◽

General Term ◽

The Difference ◽

Common Sole

In farmed flatfish, such as common sole, color disturbances are common. Dyschromia is a general term that includes the color defects on the blind and ocular sides of the fish. The purpose was to examine the difference in gene expression between normal pigmented and juveniles who present ambicoloration. The analysis was carried out with next-generation sequencing techniques and de novo assembly of the transcriptome. Transcripts that showed significant differences (FDR < 0.05) in the expression between the two groups, were related to those of zebrafish (Danio rerio), functionally identified, and classified into categories of the gene ontology. The results revealed that ambicolorated juveniles exhibit a divergent function, mainly of the central nervous system at the synaptic level, as well as the ionic channels. The close association of chromophore cells with the growth of nerve cells and the nervous system was recorded. The pathway, glutamate binding–activation of AMPA and NMDA receptors–long-term stimulation of postsynaptic potential–LTP (long term potentiation)–plasticity of synapses, appears to be affected. In addition, the development of synapses also seems to be affected by the interaction of the LGI (leucine-rich glioma inactivated) protein family with the ADAM (a disintegrin and metalloprotease) ones.

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Long-term risks after kidney donation: how do we inform potential donors? A survey from DESCARTES and EKITA transplantation working groups

Nephrology Dialysis Transplantation ◽

10.1093/ndt/gfab035 ◽

2021 ◽

Author(s):

Geir Mjøen ◽

Umberto Maggiore ◽

Nicos Kessaris ◽

Diederik Kimenai ◽

Bruno Watschinger ◽

...

Keyword(s):

Evaluation Process ◽

Kidney Donation ◽

Kidney Donors ◽

Living Kidney Donors ◽

Relative Risks ◽

Written Information ◽

The Difference ◽

Stage Renal Disease ◽

End Stage

Abstract Background Publications from the last decade have increased knowledge regarding long-term risks after kidney donation. We wanted to perform a survey to assess how transplant professionals in Europe inform potential kidney donors regarding long-term risks. The objectives of the survey were to determine how they inform donors and to what extent, and to evaluate the degree of variation. Methods All transplant professionals involved in the evaluation process were considered eligible, regardless of the type of profession. The survey was dispatched as a link to a web-based survey. The subjects included questions on demographics, the information policy of the respondent and the use of risk calculators, including the difference of relative and absolute risks and how the respondents themselves understood these risks. Results The main finding was a large variation in how often different long-term risks were discussed with the potential donors, i.e. from always to never. Eighty percent of respondents stated that they always discuss the risk of end-stage renal disease, while 56% of respondents stated that they always discuss the risk of preeclampsia. Twenty percent of respondents answered correctly regarding the relationship between absolute and relative risks for rare outcomes. Conclusions The use of written information and checklists should be encouraged. This may improve standardization regarding the information provided to potential living kidney donors in Europe. There is a need for information and education among European transplant professionals regarding long-term risks after kidney donation and how to interpret and present these risks.

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Tooth loss in complying and non-complying periodontitis patients with different periodontal risk levels during supportive periodontal care

Clinical Oral Investigations ◽

10.1007/s00784-021-03895-8 ◽

2021 ◽

Author(s):

Roberto Farina ◽

Anna Simonelli ◽

Andrea Baraldi ◽

Mattia Pramstraller ◽

Luigi Minenna ◽

...

Keyword(s):

Active Treatment ◽

Clinical Relevance ◽

Tooth Loss ◽

Loss Rate ◽

Risk Levels ◽

Recall Interval ◽

Level 3 ◽

The Difference ◽

Periodontal Risk

Abstract Objectives To evaluate yearly tooth loss rate (TLR) in periodontitis patients with different periodontal risk levels who had complied or not complied with supportive periodontal care (SPC). Materials and methods Data from 168 periodontitis patients enrolled in a SPC program based on a 3-month suggested recall interval for at least 3.5 years were analyzed. For patients with a mean recall interval within 2–4 months (“compliers”) or > 4 months (“non-compliers”) with different PerioRisk levels (Trombelli et al. 2009), TLR (irrespective of the cause for tooth loss) was calculated. TLR values were considered in relation to meaningful TLR benchmarks from the literature for periodontitis patients either under SPC (0.15 teeth/year; positive benchmark) or irregularly complying with SPC (0.36 teeth/year; negative benchmark). Results In both compliers and non-compliers, TLR was significantly below or similar to the positive benchmark in PerioRisk level 3 (0.08 and 0.03 teeth/year, respectively) and PerioRisk level 4 (0.12 and 0.18 teeth/year, respectively). Although marked and clinically relevant in non-compliers, the difference between TLR of compliers (0.32 teeth/year) and non-compliers (0.52 teeth/year) with PerioRisk level 5 and the negative benchmark was not significant. Conclusion A SPC protocol based on a 3- to 6-month recall interval may effectively limit long-term tooth loss in periodontitis patients with PerioRisk levels 3 and 4. A fully complied 3-month SPC protocol seems ineffective when applied to PerioRisk level 5 patients. Clinical relevance PerioRisk seems to represent a valid tool to inform the SPC recall interval as well as the intensity of active treatment prior to SPC enrollment.

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Imitated Whole Tree Harvesting Show Negligible Effect on Economic Value of Spruce Stands

Forests ◽

10.3390/f12070841 ◽

2021 ◽

Vol 12 (7) ◽

pp. 841

Author(s):

Iveta Desaine ◽

Annija Kārkliņa ◽

Roberts Matisons ◽

Anna Pastare ◽

Andis Adamovičs ◽

...

Keyword(s):

Norway Spruce ◽

Economic Value ◽

Forest Types ◽

Spruce Stands ◽

The Difference ◽

Growing Conditions ◽

Whole Tree Harvesting ◽

Whole Tree ◽

Tree Harvesting

The increased removal of forest-derived biomass with whole-tree harvesting (WTH) has raised concerns about the long-term productivity and sustainability of forest ecosystems. If true, this effect needs to be factored in the assessment of long-term feasibility to implement such a drastic forest management measure. Therefore, the economic performance of five experimental plantations in three different forest types, where in 1971 simulated WTH event occurred, was compared with pure, planted and conventionally managed (CH) Norway spruce stands of similar age and growing conditions. Potential incomes of CH and WTH stands were based on timber prices for period 2014–2020. However, regarding the economics of root and stump biomass utilization, they were not included in the estimates. In any given price level, the difference of internal rate of return between the forest types and selected managements were from 2.5% to 6.2%. Therefore, Norway spruce stands demonstrate good potential of independence regardless of stump removal at the previous rotation.

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Fibromuscular dysplasia with recurrence after “long-term” following percutaneous transcatheter renal angioplasty: two case reports with a review of 26 patients

BMC Nephrology ◽

10.1186/s12882-021-02342-w ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Shuntaro Oribe ◽

Takafumi Toyohara ◽

Eikan Mishima ◽

Takehiro Suzuki ◽

Koichi Kikuchi ◽

...

Keyword(s):

Fibromuscular Dysplasia ◽

Age Of Onset ◽

Case Reports ◽

Case Presentation ◽

Renal Angioplasty ◽

Long Term Follow Up ◽

Percutaneous Transluminal Renal Angioplasty ◽

The Difference

Abstract Background Fibromuscular dysplasia (FMD) often causes renal artery stenosis with renovascular hypertension. Recent clinical outcomes encourage percutaneous transluminal renal angioplasty (PTRA) to treat FMD; however, the necessary follow-up period remains unclear. Moreover, previous studies have not revealed the difference in the period until recurrence between two major types of FMD—multifocal and focal. Case presentation We describe two patients with multifocal FMD who developed hypertension during their teenage years and had recurrence of FMD > 10 years after PTRA. We further examined the types of FMD and age of onset in 26 patients who underwent PTRA. The period until recurrence of multifocal FMD was longer than that of focal FMD. Moreover, patients with early-onset multifocal FMD are likely to have a delayed recurrence after PTRA compared to other types. Conclusions Our report suggests that patients with multifocal FMD, especially those with onset at an early age, may need long-term follow-up for at least ≥ 10 years.

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