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use natural gas consumption in 201Scenarios to decarbonize residential water heating in California
This paper presents the first detailed long-term stock turnover model to investigate scenarios to decarbonize the residential water heating sector in California, which is currently dominated by natural gas. We model a mix of water heating (WH) technologies including conventional and on-demand (tank-less) natural gas heating, electric resistance, existing electric heat pumps, advanced heat pumps with low global warming refrigerants and solar thermal water heaters. Technically feasible policy scenarios are developed by considering combinations of WH technologies with efficiency gains within each technology, lowering global warming potential of refrigerants and decreasing grid carbon intensity. We then evaluate energy demand, emissions and equipment replacement costs of the pathways. We develop multiple scenarios by which the annual greenhouse gas emissions from residential water heaters in California can be reduced by over 80% from 1990 levels resulting in an annual savings of over 10 Million Metric Tons by 2050. The overall cost of transition will depend on future cost reductions in heat pump and solar thermal water heating equipment, energy costs, and hot water consumption
Experimental Appropriateness Verification of K. Gorodetsky`s Mathematical Model for Losses Determinination in Hydrostatic Transmissions for Modern Hydrolic Machines
There were experimentally obtained dependences of efficiency coefficients for two hydrostatic transmissions of various sizes and performance on the basis of axial-piston hydraulic machines under various loading conditions. The experimental data is compared with the calculated one obtained using the mathematical model of K. Gorodetsky. The object of study was the hydrostatic monoblock transmission manufactured in 1999 and the hydrostatic transmission made in 2012 with a spaced hydraulic pump and hydraulic motor
TTX-sensitive Na+ and nifedipine-sensitive Ca2+ channels in rat vas deferens smooth muscle cells
The inward currents in single smooth muscle cells (SMC) isolated from epididymal part of rat vas deferens have been studied using whole-cell patch-clamp method. Depolarising steps from holding potential -90 mV evoked inward current with fast and slow components. the component with slow activation possessed voltage-dependent and pharmacological properties characteristic for Ca2+ current carried through L-type calcium channels (I-Ca). the fast component of inward current was activated at around -40 mV, reached its peak at 0 mV, and disappeared upon removal of Na ions from bath solution. This current was blocked in dose-dependent manner by tetrodotoxin (TTX) with an apparent dissociation constant of 6.7 nM. On the basis of voltage-dependent characteristics, TTX sensitivity of fast component of inward current and its disappearance in Na-free solution it is suggested that this current is TTX-sensitive depolarisation activated sodium current (I-Na) Cell dialysis with a pipette solution containing no macroergic compounds resulted in significant inhibition of I-Ca (depression of peak I-Ca by about 81% was observed by 13 min of dialysis), while I-Na remained unaffected during 50 min of dialysis. These data draw first evidence for the existence of TTX-sensitive Na+ current in single SMC isolated from rat vas deferens. These Na+ channels do not appear to be regulated by a phosphorylation process under resting conditions. (C) 1999 Elsevier Science B.V. All rights reserved.Natl Acad Sci Ukraine, Bogomoletz Inst Physiol, Nerve Muscle Physiol Dept, UA-24 Kiev, UkraineUniversidade Federal de São Paulo, Escola Paulista Med, Dept Pharmacol, São Paulo, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Pharmacol, São Paulo, BrazilWeb of Scienc
Some aspects of teaching medical informatics at medical universities
В статті розглядаються питання сучасного викладання медичної
інформатики студентам медичних університетів. В роботі описано основну мету
дисципліни, пропонуються шляхи вдосконалення її. Актуальність даної тематики
підтверджує те, що наукові методи та інструментальні засоби все більш широко
проникають в будь-які галузі життєдіяльності людини, і медицина не є
виключенням, Саме це надає медичній інформатиці характер міждисциплінарної
галузі, яка набуває все більш важливе загальнонаукове і загальноосвітнє значення.
Розкрито важливе питання забезпечення формування у сучасного лікаря цілісного
системного наукового світогляду на проблеми інформатизації охорони здоров'я.
Дана стаття буде цікава викладачам закладів вищої медичної освіти.The article discusses the issues of up-to-date teaching medical informatics to
students of medical universities. The paper describes the main goal of the discipline,
suggests ways to improve it. The relevance of this topic lies in the fact that scientific
methods and tools are increasingly penetrating into any branch of human life, and
medicine is not an exception. That is why Medical Informatics belongs to
interdisciplinary field, and acquires important scientific and educational value. Authors
disclosed the important issue of the formation of a holistic and scientific worldview in
modern doctors on the problems of health care informatization. This article would be
interesting to teachers of higher educational institutions of a medical profile
Cluster analysis and classification of process data by use of principal curves
Thesis (M.Ing.) -- University of Stellenbosch, 1999.ENGLISH SUMMARY: In this thesis a new method of clustering as wen as a new method of classification is
proposed. Cluster analysis is a statistical method used to search for natural groups in
an unstructured multivariate data set. Clusters are obtained in such. a way that the
observations belonging to the same group are more alike than observations across
groups. For instance, long data records are found in mineral processing plants, where
the data can be reduced to clusters according to different ore types. Most of the
existing clustering methods do not give reliable results when applied to engineering
data, since these methods were mainly developed in the domains of psychology and
biology.
Classification analysis can be regarded as the natural continuation of cluster analysis.
In order to classify objects, two types of observations are needed. The first are those
observations whose group memberships are known a priori, which can be acquired
through cluster analysis. The second kind of observations are those whose group
memberships are unidentified. By means of classification these observations are
allocated to one of the existing groups.
Both of the proposed techniques are based on the use of a smooth one-dimensional
curve, passing through the middle of the data set. To formalise such an idea,
principal curves were developed by Hastie and Stuetzle (1989). A principal curve
summarises the data in a non-linear fashion. For clustering, the principal curve of the
entire unstructured data set is extracted. This one-dimensional representation of the
data set is then used to search for different clusters. For classification, a principal
curve is fitted to every known group in the data set. The observations to be assigned
to one of the known groups are allocated to the group closest to the new point.
Clustering with principal curves grouped engineering data better than most of the
well-known clustering algorithms. Some shortcomings of this method were also
established. Classification with principal curves gave similar, optimal results as compared to some existing classification methods. This classification method can be
applied to data of any distribution, unlike statistical classification techniques.AFRIKAANSE OPSOMMING: In hierdie tesis word 'n nuwe metode elk vir trosanalise en klassifikasie analise
voorgestel. Trosanalise is 'n statistiese tegniek waarrnee natuurlike groepe in 'n
ongestruktureerde meerveranderlike datastel gevind word. Groepe word op so 'n
wyse verkry dat die waamemings in dieselfde groep meer eenders is as waarnemings
tussen groepe. Byvoorbeeld, in mineraalaanlegte is lang datarekords algemeen, wat
deur middel van trosanalise gereduseer kan word na verskillende groepe,
ooreenkomstig verskillende ertstipes. Die meerderheid bestaande groeperingsmetodes
lewer nie betroubare resultate in hul toepassing op ingenieursdata nie, aangesien
hierdie tegnieke meestal hul oorsprong in die sielkundige en biologiese velde het.
Klassifikasie analise kan gesien word as die natuurlike opvolging van trosanalise.
Om objekte te klassifiseer, word gebruik gemaak van twee soorte waarnemings. Die
eerste tipe is daardie waamemings met a priori bekende groepsidentiteite, wat deur
trosanalise gevind kan word. Die tweede soort is die waarnemings met onbekende
groepsidentiteite. Elkeen van hierdie waarnemings kan deur middel van klassifikasie
toegewys word aan een van die bestaande groepe.
Beide hierdie voorgestelde tegnieke is gebaseer op die gebruik van 'n gladde, eendimensionele
kromme wat deur die middel van die datastel beweeg. Om hierdie idee
te formaliseer, is hoojkrommes ontwikkel deur Hastie en Stuetzle (1989). 'n
Hoofkromme gee 'n nie-lineere opsomming van die data. Vir groeperingsdoeleindes
word 'n hoofkromme uit die algehele ongestruktureerde datastel onttrek. Met
klassifikasie word'n hootkurwe aan elke bekende groep in die datastel gepas. Die
waameming wat aan een van die bestaande groepe toegewys moet word, word in die
groep naaste aan die betrokke punt geplaas.
Groepering met behulp van hoofkrommes, het met ingenieursdata beter resultate
gelewer as meeste van die bestaande tegnieke. Deur middel van praktiese voorbeelde
is sekere tekortkominge van hierdie groeperingsmetode vasgestel. Klassifikasie met behulp van hoofkrornmes lewer soortgelyke, optimale resultate as die van bekende
vergelykende tegnieke. Die voorgestelde klassifikasie tegniek kan toegepas word op
datastelle van enige verde ling, in teenstelling met die statistiese klassifikasietegnieke.Maste
Екстракорпоральне поширення кісткового цементу після перкутанної кіфопластики
Мета. Вивчити особливості та клінічні прояви екстракорпорального поширення (ЕКП) кісткового цементу (КЦ) після перкутанної балонної кіфопластики (КП) з приводу остеопенічних та остеолітичних уражень хребців.
Матеріали і методи. Проведено ретроспективне дослідження щодо 50 пацієнтів після КП з приводу остеопоротичних компресійних переломів хребців (24 пацієнти, прооперовано 51 хребець), метастатичних уражень (7 пацієнтів і 10 хребців), мієломної хвороби (4 пацієнти і 10 хребців) та агресивних гемангіом (15 пацієнтів і 23 хребці). ЕКП КЦ оцінювали за даними післяопераційної мультиспіральної комп’ютерної томографії окремо у венозні судини та через дефекти кіркового шару хребців.
Результати. ЕКП КЦ виявлено на 52 (50,5%) із 103 оперованих рівнів та в півнепарну вену (у 1 пацієнта) і гілки легеневої артерії (у 2 пацієнтів). Найчастіше ЕКП КЦ реєстрували після КП з приводу метастатичних уражень хребців, переважно в основно-хребцеві вени. ЕКП КЦ в міжхребцеві диски виявлено тільки після КП з приводу остеопоротичних переломів (15,7% спостережень). Спостерігали клінічні прояви ЕКП КЦ в хребтовий канал як у вени, так і через дефекти кіркового шару хребців.
Висновки. КП є безпечним методом укріплення хребців, уражених різноманітною патологією. Клінічно значущі прояви ЕКП КЦ спостерігали лише в разі потрапляння КЦ в хребтовий канал як у венозні сплетення, так і через дефекти кіркового шару хребців. ЕКП КЦ не слід розглядати як самостійне ускладнення КП
Analysis of Multiwalled Carbon Nanotubes as Waveguides and Antennas in the Infrared and the Visible Regimes
The propagation of azimuthally symmetric guided waves in multiwalled carbon
nanotubes (MWCNTs) was analyzed theoretically in the mid-infrared and the
visible regimes. The MWCNTs were modeled as ensembles of concentric,
cylindrical, conducting shells. Slightly attenuated guided waves and antenna
resonances due to the edge effect exist for not-too-thick MWCNTs in the far-
and mid-infrared regimes. Interband transitions hinder the propagation of
guided waves and have a deleterious effect on the performance of a
finite-length MWCNT as an antenna. Propagation of surface-plasmon waves along
an MWCNT with a gold core was also analyzed. In the near-infrared and the
visible regimes, the shells behave effectively as lossy dielectrics suppressing
surface-plasmon-wave propagation along the gold core.Comment: 13 pages, 8 figure
Effect of platelet-rich fibrin matrix in complex with artificial material Nubiplant on expression of chondrogenic marker genes and morphogenesis of the nucleus pulposus cells of intervertebral discs in rats
The purpose was to study the barrier and biological properties of platelet-rich fibrin matrix (PRFM), an artificial biopolymer Nubiplant, and a mixture of PRFM / Nubiplant by assessing the viability and morphological characteristics of nucleus pulposus (NP) cells in rats, as well as the expression level of chondrogenic marker genes during cell cultivation in the presence of these matrices.Materials and methods. PRFM was obtained from platelet-rich plasma using a SiO2 coagulation activator. A suspension of nucleus pulposus cells was obtained from the caudal spine of rats. Cultivation was carried out in the presence of one of three matrices — PRFM, Nubiplant, or their mixture for 3, 7, and 14 days under standard culture conditions in an EC-160 incubator (Nüve, Turkey). Observation of the living culture was carried out in the area bordering with the matrix within one field of view using an inverted microscope (Nicon TS100, Japan). The expression of chondrogenic marker genes in the cell culture of the NP was determined by the method of PCR with reverse transcription.Results. The study of the viability and morphological characteristics of NP cells during their cultivation for 3, 7, and 14 days in the presence of PRFM, PRFM / Nubiplant, or Nubiplant showed a decrease in the content of living cells in control samples; in cultures with PRFM and PRFM / Nubiplant, the number of living cells significantly exceeded the control values, aggregation of cells was observed in the area bordering with the matrices from the side of the application. None of the experimental samples showed the outflow of cells to the opposite side of the matrix after 14 days of cultivation; thus, PRFM, Nubiplant, and their mixture can perform barrier functions to keep the cell population in a certain location. Expression of the COL II, ACAN, GPC3, ANXA3, PTN, MGP, and VIM genes by the NP cells during cultivation for 3 and 7 days in the presence of PRFM and PRFM / Nubiplant increased as compared to the control samples.Conclusions. The use of PRFM, Nubiplant, or a mixture of PRFM / Nubiplant during the cultivation of NP cells demonstrated the absence of cell outflow to the opposite side of the studied matrices during the study period (14 days). The use of PRFM, Nubiplant, or a mixture of PRFM / Nubiplant promoted the formation of cell colonies with chondrocyte-like morphology in the zone bordering with the matrices and maintained cell viability throughout the study period. PRFM and PRFM / Nubiplant contributed to the maintenance of the expression of chondrogenic genes in the NP cells in the zone bordering the matrices. The results obtained indicate the positive effect of the matrix based on platelet-rich fibrin on the NP cells and its barrier functions, which is promising for the use of PRMF for preventing the formation of cicatricial adhesion
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