288 research outputs found
Sodium channel inactivation kinetics of rat sensory and motor nerve fibres and their modulation by glutathione
Na+ channel currents of rat motor and sensory nerve fibres were studied with the patch-clamp technique on enzymatically demyelinated axons. Differences between motor and sensory fibres in multi-channel inactivation kinetics and the gating of late single-channel currents were investigated. In the axon-attached mode, inactivation of multi-channel Na+ currents in sensory axons was best fitted with a single time constant while for motor axons two time constants were needed. Late single-channel currents in sensory axons were characterized by short openings whereas motor axons exhibited additional long single-channel openings. In contrast, in excised, inside-out membrane patches, no differences between motor and sensory fibres were found: in both types of fibre inactivation of multi-channel Na+ currents proceeded with two time constants and late single-channel currents showed short and long openings. After application of the reducing agent glutathione to the cytoplasmic side of excised inside-out patches, inactivation of Na+ currents in both motor and sensory fibres proceeded with a single, fast exponential time constant and late currents appeared with short openings only. These data indicate that the axonal metabolism may contribute to the different inactivation kinetics of Na+ currents in motor and sensory nerve fibres
Spatially Resolved NMR Relaxation Rate in a Noncentrosymmetric Superconductor
We numerically study the spatially-resolved NMR around a single vortex in a
noncentrosymmetric superconductor such as CePt3Si.
The nuclear spin-lattice relaxation rate 1/T1 under the influence of the
vortex core states is calculated for an s+p-wave Cooper pairing state.
The result is compared with that for an s-wave pairing state.Comment: 2 pages; submitted to Proc. of SCES'0
Sodium channel inactivation kinetics of rat sensory and motor nerve fibres and their modulation by glutathione
Na+ channel currents of rat motor and sensory nerve fibres were studied with the patch-clamp technique on enzymatically demyelinated axons. Differences between motor and sensory fibres in multi-channel inactivation kinetics and the gating of late single-channel currents were investigated. In the axon-attached mode, inactivation of multi-channel Na+ currents in sensory axons was best fitted with a single time constant while for motor axons two time constants were needed. Late single-channel currents in sensory axons were characterized by short openings whereas motor axons exhibited additional long single-channel openings. In contrast, in excised, inside-out membrane patches, no differences between motor and sensory fibres were found: in both types of fibre inactivation of multi-channel Na+ currents proceeded with two time constants and late single-channel currents showed short and long openings. After application of the reducing agent glutathione to the cytoplasmic side of excised inside-out patches, inactivation of Na+ currents in both motor and sensory fibres proceeded with a single, fast exponential time constant and late currents appeared with short openings only. These data indicate that the axonal metabolism may contribute to the different inactivation kinetics of Na+ currents in motor and sensory nerve fibres
Interdependence of fundamental and applied research in material science
Development of materials with desirable properties essentially depends on realization of interdependence: natural science ⇔ technical sciences. Taking this into account, in order to develop of new advanced materials it is essential to determine principles that characterize this interdependency. Therefore, in this article the principles of fundamental research and the importance of obtained results are considered and implemented in the field of technical realizations
Važnija eksterijerna i reproduktivna svojstva populacije engleskog punokrvnog konja gajenog na ergeli 'Ljubičevo', Srbija
The investigation included 5 stallions (average age of 10.40 years) and 33 mares (average age of 10.33 years) with pedigree of the English Thoroughbred horse breed that are used for breeding on the Stud Farm Ljubicevo - Serbia. The investigation of some significant properties relating to the exterior (at stallions) and reproductive ones (at mares) were carried out in the year 2009. The following average exterior (body) measures of the stallions: the body mass (474.80 kg), withers height (160.46 cm), trunk or body length (161.88 cm), breast circumference (187.96 cm) and tibia circumference (19.22 cm) were within the standards of this horse breed of the age. The gestation period at mares, regardless the sex of a colt, averagely lasted 337.70 days. With the mares having had a male colt, the gestation lasted a little bit longer (338.92 days) than with the mares having had female colts (336.90 days). The difference in the gestation duration (2.02 days) was not statistically significant (P>0.05). Between the age of the mares and the gestation duration (regardless the sex of a colt) it was found a positive slight correlation (rp=0.320). Furthermore, between the age of the mares and the gestation duration it was found medium (rp=0.453) correlation at male colts, and quite poor correlation (rp=0.202) at female colts. Found coefficients of the phenotype correlation were not statistically confirmed (P>0.05).Istraživanjima je obuhvaćeno 5 pastuva (prosečne starosti 10,40 godina) i 33 kobile (prosečne starosti 10,33 godina) sa poznatim poreklom (pedigreom) engleske punokrvne rase konja koja se na ergeli Ljubičevo - Srbija aktivno koriste u priplodu. Utvrđivanja važnijih eksterijernih (pastuvi), odnosno reproduktivnih svojstava (kobile) sprovedena su u 2009. godini. Utvrđene prosečne eksterijerne (telesne) mere pastuva: telesna masa (474,80 kg), visina grebena (160,46 cm), dužina trupa - tela (161,88 cm), obim grudi (187,96 cm) i obim cevanice (19,22 cm) su bile u okviru standarda ove rase konja u odgovarajućoj starosnoj dobi. Bremenitost (gestacija) kobila, bez obzira na pol ždrebeta, u proseku je trajala 337,70 dana. Kod kobila koje su oždrebile mušku ždrebad bremenitost je trajala nešto duže (338,92 dana), nego kod kobila koje su oždrebile žensku ždrebad (336,90 dana). Razlika u trajanju bremenitosti (2,02 dana) nije bila statistički signifikantna (P>0,05). Između starosti kobila i trajanja bremenitosti (bez obzira na pol ždrebeta) utvrđena je pozitivna slaba korelaciona povezanost (rp=0,320). Zatim, između starosti kobila i trajanja bremenitosti utvrđena je srednja (rp=0,453) korelaciona povezanost kod muške ždrebadi, odnosno jako slaba (rp=0,202) kod ženske ždrebadi. Utvrđeni koeficijenti fenotipske korelacije nisu bili statistički potvrđeni (P>0,05)
Primary energy savings using heat storage for biomass heating systems
District heating is an efficient way to provide heat to residential, tertiary and industrial users. The heat storage unit is an insulated water tank that absorbs surplus heat from the boiler. The stored heat in the heat storage unit makes it possible to heat even when the boiler is not working, thus increasing the heating efficiency. In order to save primary energy (fuel), the boiler operates on nominal load every time it is in operation (for the purpose of this research). The aim of this paper is to analyze the water temperature variation in the heat storage, depending on the heat load and the heat storage volume. Heat load is calculated for three reference days, with average daily temperatures from -5 to 5°C. The primary energy savings are also calculated for those days in the case of using heat storage in district heating.[Projekat Ministarstva nauke Republike Srbije, br. TR 33051: The concept of sustainable energy supply of settlements with energy efficient buildings
Effect of additional exercise programme for functional arm kinesiotherapy on the quality of life following operative hip osteoarthritis treatment
Uvod: Osteoartritis kuka najčešće dovodi uz ostale pridružene bolesti do generalno lošeg
zdravstvenog statusa osoba gerijatrijske populacije. Krajnji stadijum osteoartritisa kuka se
uspešno tretira operativno, totalnom artroplastikom. Nakon totalne artroplastike kuka
sledstvena primena rehabilitacionih programa je jedini izbor za obnovu mobilnosti i fizičke
funkcionalnosti.
Cilj: Da se odredi efektivnost dodatog rehabilitacionog programa za vežbanje ruku i gornjih
partija tela na ishode rehabilitacije nakon artroplastike kuka.
Metod: Studija je dizajnirana kao prospektivna, paralelna, randomizovana, kontrolna
studija, sprovedena na odeljenju ortopedije i rehabilitacije. U istraživanje je bilo uključeno
ukupno 70 pacijenata, starijih od 60 godina od ukupno regrutovanih 98 nakon primenjenih
kriterijuma isključivanja u postoperativnoj rehabilitaciji nakon ugradnje totalne
artroplastike kuka. Učesnici interventne grupe su uzeli učešće u suplementarni program
vežbanja ruku i gornjih partija tela uz standardni rehabilitcioni program, dok su učesnici
kontrolne grupe imali samo standardni rehabilitacioni program. Primarni ishod
rehabilitacije je procenjivan Harisovim upitnikom kojim su se merile promene u fizičkim
sposobnostima i u funkcionalnosti afektiranog kuka, a sekundarnim ishodima su merene
mišićna snaga preko snage stiska šaka korišćenjem dinamometra kao i kvalitet života
korišćenjem opšeg upitnika o zdravlju SF-36.
Rezultati: Interventna grupa je pokazala signifikantno poboljšanje u odnosu na kontrolnu
grupu u fizičkim sposobnostima merenim Harisovim skorom nakon dve nedelje (prosečna
razlika = 4.7 boda) i nakon 12 nedelja (prosečna razlika = 5.85 bodova). Takođe su učesnici
interventne grupe pokazali statistički veće poboljšanje nakon 12 nedelja: u boljoj mišićnoj
snazi merenoj stiskom obe šake (prosečna razlika dominantne šake =4.16 i druge
strane=2.8) i u domenu Fizička uloga SF-36 upitnika (prosečna razlika=6.42 boda).
Metodom linearne regresione analize nakon prilagođavanja na sociodemografske i kliničke
karakteristike dodatni program vežbanja koji je praktikovala interventna grupa se pokazao
kao nezavisni prediktor za bolju fizičku fukcionalnost (Harisov skor) nakon dve (b=4.593;
p=0.018) i nakon 12 (b=3.324; p=0.005) nedelja; bolju mišićnu snagu (stisak šaka) nakon
12 nedelja za dominantnu (b=1.258; p=0.007) i za nedominantnu šaku (b=1.176; p=0.001),
kao i za bolji kvalitet života povezanog sa zdravljem SF 36 u sledećim domenima: Fizičko
fukcionisanje nakon 2 nedelje (b=5.999; p=0.004), Fizička uloga nakon 12 nedelja
(b=6.909; p=0.040), Telesni bol nakon 12 nedelja (b=10.677; p=0.002), i Mentalno zdravlje
nakon 2 nedelje (b=9.562; p=0.006)...Introduction: Hip osteoarthritis is a cause of joint pain and disability in elderly people,
commonly associated with their poor general health status. The end stage hip osteoarthritis
can be successfully treated with total hip arthroplasty. Physical exercise therapy approaches
are widely accepted as treatment of choice in order to restore full mobility and physical
functions after hip replacement surgery.
Objective: To determine whether arm and upper body exercises in addition to the standard
rehabilitation programme improve outcomes after hip arthroplasty.
Desig: Prospective, parallel, randomized, controlled trial.
Setting: Orthopedic and rehabilitation departments.
Subjects: 70 patients >60 years of age, who underwent hip replacement, out of 98 eligible
candidates after exclusion criteria were implemented.
Interventions: The study group took part in the Supplementary arm and upper body exercise
programme to be compared with the Standard rehabilitation programme group.
Main outcome: The primary outcome was Harris Hip Score. Secondary outcomes were:
Hand grip strength and Medical Outcomes Study 36-Item Short-Form Health Survey.
Outcomes were assessed preoperatively, two weeks after surgery and at three months
follow-up.
Results: In intervention group significant improvements were found in functional ability -
Harris Hip Score after 2 weeks (mean difference = 4.7 points) and 12 weeks (mean
difference = 5.85 points), and after three months:in muscle strength - Handgrip for both
hands (mean difference for dominant hand= 4.16 and for the other hand=2.8) and in Role-
Physical dimension SF-36 Health Survey (mean difference=6.42 points). After adjustment
the study group is an independent predictor of a significantly greater Harris Hip Score after:
two (b=4.593; p=0.018) and 12 (b=3.324; p=0.005) weeks; greater Hand Grip Strength at
12 weeks for: dominant (b=1.258; p=0.007) and non-dominant hand (b=1.176; p=0.001)
and better scores on SF-36 dimensions: Physical-Functioning at two weeks(b=5.999;
p=0.004), Role-Physical at 12 weeks (b=6.909; p=0.040), Bodily-Pain at 12 weeks
(b=10.677; p=0.002), and Mental Health at two weeks (b=9.562; p=0.006)..
Sintering of mechanically activated magnesium-titanate and barium-zinc-titanate ceramics
In this article the influence of mechanical activation on sintering process of magnesium-titanate and barium-zinc-titanate ceramics has been investigated. Both nonactivated and mixtures treated in planetary ball mill for 80 minutes were sintered at 1100ºC and 1300ºC. The influence of mechanical activation on phase composition and crystal structure has been analyzed by XRD, while the effect of activation and sintering process on microstructure was investigated by scanning electron microscopy. It has been established that temperature of 1100ºC was to low to induce final sintering stage for both systems. Moreover, we concluded that barium-zinc-titanate ceramics exhibited better sinterability than magnesium-titanate ceramics
Colloid electrohydrodynamics
This brief extracted review presents the recent development in basic and applied science and engineering of finely dispersed particles and related systems in general, but more profound and in-depth treatise are related to the liquid-liquid finely dispersed systems, i.e. emulsions and double emulsions. Twenty-five years ago, the idea, at first very fogy, came out from the pilot plant experiments related to the extraction Of uranium from wet phosphoric acid. In particular the solution of the entrainment problems, breaking of emulsions/double emulsions, as the succession of the extraction and stripping operations/processes, was performed In this pilot plant, secondary liquid-liquid phase separation loop was designed and carried out. The loop consisted of a lamellar coalescer and four flotation cells in series. Central equipment in the loop, relevant to this investigation, was the lamellar coalescer. The phase separation in this equipment is based on the action of external forces of mechanical and/or electrical origin, while adhesive processes at the inclined filling plates occur. Since many of related processes, e.g. adhesive processes, rupture processes and coalescence, were not very well understood, deeper research of these events and phenomena was a real scientific challenge
The Loss of Deontology on the Road to Apathy: Examples of Homelessness and IVF Now, with Disaster to Follow
Vulnerable groups, from contemporary homeless people to IVF embryos may fall between the cracks of otherwise good social values, such as government welfare programs and individual autonomy. These present and slow disasters are in principle no different from more immediate catastrophes resulting from natural events or wars that harm civilians. The failure to respond with indignation and demands for change constitutes apathy, which is also an absence of deontology. We begin with concrete examples of social apathy, in Part 1. Our examples are homelessness and IVF, neither of which are usually considered disasters but both of which are in fact ongoing disasters within normal society. Part 2. is a discussion of theoretical and practical deontology that is lacking in these examples
- …