14 research outputs found

    Dual responsive hybrid hydrogels for controlled release of local anesthetic

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    Inteligentni hidrogelovi, kao što su pH osetljivi hidrogelovi na bazi poli(metakrilne kiseline) (PMAA), imaju veliku primenu u ciljanoj dostavi lekova. Međutim, slaba mehanička svojstva često ograničavaju primenu PMAA. Kako bi se prevazišlo navedeno ograničenje, nanoceluloza (NC) je prvo ekstrakovana iz drvnog otpadnog materijala, a zatim dodata u PMAA, zato što je NC biokompatibilna, netoksična i ima odlična mehanička svojstva. Zatim je dodata karboskimetil celuloza (CMC) (celulozni derivat koji se često koristi za kontrolisano otpuštanje lekova). CMC može da stabilizuje nanočestice magnetita (MN) koje su takođe dodate. MN mogu značajno da poboljšaju mehanička svojstva hidrogelova i takođe poseduju magnetna svojstva zbog čega imaju primenu za ciljano otpuštanje lekova. Ovako dobijeni materijal bi mogao da zaštiti lek, dostavi ga do mesta delovanja, kontroliše brzinu njegovog otpuštanja i na taj način omogući efikasno dejstvo leka sa smanjenim neželjenim efektima. Lokalni anestetik – lidokain hidrohlorid (LH) se često u tretmanima injektira što može imati ozbiljne neželjene efekte. Inkapsulacijom LH u hidrogelove na bazi PMAA, NC, CMC i MN (PMNC/MN-L) rešen je navedeni problem. Karakterizacija PMNC/MN-L hidrogelova je izvedena primenom FTIR i SEM spektroskopija i kompresionim testovima, a zatim je analizirano bubrenje hidrogelova i otpuštanje LH. U ovom radu predstavljen je jedinstveni način „zelene” sinteze hibridnih hidrogelova osetljivih na spoljne stimulanse unapređenih svojstava i njihove primene za kontrolisano otpuštanje lokalnog anestetika sa smanjenim neželjnim efektima

    The short-term and long-term effects of parental age in the bean weevil (Acanthoscelides obtectus)

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    We examined the influence of parental age on life history traits of their offspring in the lines of bean weevil that have evolved different rates of senescence. Measurements included preadult traits ( egg size, embryonic developmental time, total preadult developmental time, preadult viability) and adult traits ( body weight, total realized fecundity of females,first day of egg laying, early fecundity, late fecundity and longevity). The negative parental age effects were observed for all traits except for the early and total realized fecundity. We did not detect statistically significant line x parental age interactions for either preadult- or adult-survival, so offspring survival did not change with parental age after selection for early vs. late reproduction. It seems that selection acting on the quality of offspring produced by parents of different ages has not been responsible for the evolution of senescence in bean weevil.nul

    The short-term and long-term effects of parental age in the bean weevil (Acanthoscelides obtectus)

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    We examined the influence of parental age on life history traits of their offspring in the lines of bean weevil that have evolved different rates of senescence. Measurements included preadult traits ( egg size, embryonic developmental time, total preadult developmental time, preadult viability) and adult traits ( body weight, total realized fecundity of females,first day of egg laying, early fecundity, late fecundity and longevity). The negative parental age effects were observed for all traits except for the early and total realized fecundity. We did not detect statistically significant line x parental age interactions for either preadult- or adult-survival, so offspring survival did not change with parental age after selection for early vs. late reproduction. It seems that selection acting on the quality of offspring produced by parents of different ages has not been responsible for the evolution of senescence in bean weevil.nul

    Improving energy efficiency in compressed air systems - practical experiences

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    This paper presents practical experiences of savings within compressed air systems with the special attention to the compressed air end uses, particularly in pneumatic control systems. Firstly, the systematic approach to energy savings is presented. Following, various energy-saving measures have been reviewed. They encompassed system analysis and harmonization of production and consumption, minimisation of loses (leak prevention strategy, identification and quantification of leakages), possibilities for reducing pressure drop on filters, and three methods for optimization of pneumatic control: by-pass control, PWM control, and usage of exhaust air. Finally, energy conservation of a complex robotic cell with installed electric and pneumatic devices is shown

    Laboratory evolution of life‐history traits in the bean weevil (Acanthoscelides obtectus): the effects of selection on developmental time in populations with different previous history

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    Four types of laboratory populations of the bean weevil (Acanthoscelides obtectus) have been developed to study the effects of density‐dependent and age‐specific selection. These populations have been selected at high (K) and low larval densities (r) as well as for reproduction early (Y) and late (O) in life. The results presented here suggest that the r‐ and K‐populations (density‐dependent selection regimes) have differentiated from each other with respect to the following life‐history traits: egg‐to‐adult viability at high larval density (K > r), preadult developmental time (r > K), body weight (r > K), late fecundity (K > r), total realized fecundity (r > K), and longevity of males (r > K). It was also found that the following traits responded in statistically significant manner in populations subjected to different age‐specific selection regimes: egg‐to‐adult viability (O > Y), body weight (O > Y), early fecundity (Y > O), late fecundity (O > Y), and longevity of females and males (O > Y). Although several life‐history traits (viability, body weight, late fecundity) responded in similar manner to both density‐dependent and age‐specific selection regimes, it appears that underlying genetic and physiological mechanisms responsible for differentiation of the r/K and Y/O populations are different. We have also tested quantitative genetic basis of the bean weevil life‐history traits in the populations experiencing density‐dependent and age‐specific selection. Among the traits traded‐off within age‐specific selection regimes, only early fecundity showed directional dominance, whereas late fecundity and longevity data indicated additive inheritance. In contrast to age‐specific selecton regimes, three life‐history traits (developmental time, body size, total fecundity) in the density‐sependent regimes exhibited significant dominance effects. Lastly, we have tested the congruence between short‐term and long‐term effects of larval densities. The comparisons of the outcomes of the r/K selection regimes and those obtained from the low‐ and high‐larval densities revealed that there is no congruence between the selection results and phenotypic plasticity for the analyzed life‐history traits in the bean weevil

    Growth and development of Colorado potato beetle larvae, Leptinotarsa decemlineata, on potato plants expressing the oryzacystatin II proteinase inhibitor

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    Plant proteinase inhibitors (PIs) are attractive tools for crop improvement and their heterologous expression can enhance insect resistance in transgenic plants. PI oryzacystatin II (OCII), isolated from rice, showed potential in controlling pests that utilize cysteine proteinases for protein digestion. To evaluate the applicability of the OCII gene in enhancing plant defence, OCII-transformed potatoes were bioassayed for resistance to Colorado potato beetle (Leptinotarsa decemlineata Say). Feeding on transformed leaves of potato cultivars Desiree and Jelica significantly affected larval growth and development, but did not change mortality rates. During the L2 and L3 developmental stages larvae consumed the OCII-transformed foliage faster as compared to the nontransformed control. Also these larvae reached the prepupal stage (end of L4 stage) 2 days earlier than those fed on control leaves. However, the total amounts of consumed OCII-transformed leaves were up to 23 \% lower than of control, and the maximal weights of prepupal larvae were reduced by up to 18 \% as compared to larvae fed on nontransformed leaves. The reduction in insect fitness reported in this study in combination with other control measures, could lead to improved CPB resistance management in potato.Ministry of Education, Science and Technological Development of Serbia {[}ON173015
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