Assessment of the suitability of an indicator method for the determination of apparent nutrient utilization in broiler chickens

Na pitovnih piščancih smo ugotavljali vpliv vročinskega stresa na izkoristljivost hranil, merjeno z indikatorsko metodo z dvema različnima indikatorjema. Piščance smo razdelili v dva prostora v hlevu s po osem oddelki (10 piščancev na oddelekn=160). Polovici oddelkov smo 21. dan poskusa začeli za 10 ur dnevno zviševati temperaturo v prostoru na 30-32 °C (skupina vroče okoljeVO), druga polovica piščancev pa je bila nameščena v termonevtralnem okolju (TNO). Tri dni pred zaključkom poskusa smo živalim v krmo dodali titanov oksid (TiO2) kot eksterni marker. Na 42. dan smo zbrali izločke ter izračunali navidezno izkoristljivost hranljivih snovi s pomočjo indikatorske metode s TiO2 (NI-Ti). Kot indikator smo uporabili še interni marker lignin, določen kot v kislini netopen lignin (KDL), ter izračunali navidezno izkoristljivost (NI-KDL). Podatke smo obdelali s statističnim programom SAS s proceduro GLM. Pri analizi krme smo ugotovili zelo velike vsebnosti rudninskih snovi, še posebej mikrorudnin, kar je bila posledica kontaminacije surovin že pred pripravo krme. Statističnih razlik med skupinami TNO in VO nismo zasledili, ne glede na uporabljeno indikatorsko metodo. Je pa prišlo do razlike pri primerjavi indikatorskih metod, in sicer so bile praktično vse vrednosti NI-KDL manjše kot vrednosti po NI-Ti metodi. Sklepamo lahko, da je prišlo do kontaminacije izločkov z nastiljem, kar je povečalo vsebnost KDL v izločkih in s tem zmanjšalo izračunano izkoristljivost pri metodi NI-KDL.The effects of heat stress on nutrient utilization were studied in broiler chickens using indicator method with two different markers. Chickens were divided into two research facility (RF) rooms with eight compartments (10 chickens per compartmentn=160). Beginning on day 21 of the experiment, chickens in half of the compartments (RF room 1) were exposed to a temperature of 30-32°C for 10 hours per day (warm environment groupVO), while the other half of the chickens (RF room 2) were housed in a thermoneutral environment (TNO). Three days before the end of the experiment, titanium oxide (TiO2) was added to the feed as an external marker. On day 42, the excreta were collected and the apparent utilization of nutrients was calculated using the TiO2 indicator method (NI-Ti). The internal marker lignin, defined as acid detergent lignin (ADL), was also used as an indicator and apparent nutrient utilization (NI-KDL) was calculated. Data were processed using SAS statistical software with the GLM procedure. In the analysis of the feed, we found very high mineral contents, especially microminerals, which was due to contamination of the raw materials before feed preparation. No statistical differences were found in apparent nutrient utilization between the TNO and VO group, regardless of the indicator method used. However, there were differences in nutrient utilization when comparing indicator methods, and virtually all values of NI-KDL were lower than those of the NI-Ti method. This suggests that the excreta were contaminated with litter, which increased the ADL content of the excreta and thus decreased the calculated apparent nutrient utilization of the NI-ADL method

Microscopy and sensing through scattering tissues using optical microresonators

V večini bioloških tkiv močno sipanje svetlobe omejuje uporabo standardne mikroskopije. Tako so v zadnjem obdobju bile razvite številne nove metode in pristopi, ki se osredotočajo na premostitev omenjene težave. V okviru tega dela smo razvili novo metodo za globinsko slikanje ter senzoriko v tkivih, ki izkorišča optične WGM (ang. whispering gallery mode) mikroresonatorje in njihove značilnosti. Lastnosti kot so ozka spektralna emisija in velika občutljivost na spremembe okolja so ključna prednost WGM mikroresonatorjev v primerjavi s standardnimi fluorescentnimi označevalci, ki se tipično uporabljajo v bioloških raziskavah. WGM mikroresonatorje, ki se nahajajo pod oziroma znotraj sipalnega medija, lahko lokaliziramo z veliko natančnostjo s pomočjo dekompozicije zajetega spektralnega signala na prispevke posameznih mikroresonatorjev. To je možno doseči zaradi izrazitih WGM resonanc, ki navkljub potovanju svetlobe preko sipajočega medija ostanejo praktično nespremenjene. WGM mikroresonatorje zaznamujejo edinstvene spektralne lastnosti. Njihovi spektri so medsebojno razločljivi v kolikor se njihove velikosti komaj znatno razlikujejo, kar dodatno omogoča označevanje, identificiranje in spremljanje individualnih celic, medtem ko analiza izsevanih spektrov omogoča zaznavanje oziroma senzoriko številnih parametrov kot so lomni količnik, pH ali temperatura okolice. Razvita metoda s sposobnostjo simultane lokalizacije ter senzorike predstavlja vsestransko orodje na področju globinskega slikanja v tkivih.In most biological tissues, strong scattering of visible light limits the use of standard microscopy. New approaches and methods that focus on overcoming this particular problem have been developing recently. In this work, we have developed a novel technique for deep tissue imaging and sensing that utilizes optical WGM (whispering gallery mode) microresonators and their properties. The properties of spectrally narrow emission and high sensitivity to the environment make WGM microresonators superior to the standard fluorescent probes typically used in biological research. WGM microresonators placed under scattering materials or embedded inside them can be localized with high precision by decomposing the acquired spectral signal into contributions from individual microresonators. This is possible due to the fact that strong WGM resonances are mainly unaffected when propagating through a scattering medium. The spectral characteristics of each WGM microresonator are unique as long as they differ in size by only a very small margin. This can further be used to tag, identify and track individual cells. Additionally, sensing of different parameters such as refractive index, pH or temperature of the surroundings is also possible by analyzing the spectra. Simultaneous sensing and localization capabilities make the developed method a versatile tool in the field of deep tissue imaging

Supplementary file: Intracellular biocompatible hexagonal boron nitride quantum emitters as single-photon sources and barcodes

Supplementary informatio

Military dictionary by students of defence studies

The military dictionary by students of defense sciences was created during the course Slovenian language and Slovenian military idioms (2012/13 and 2013/14) at the Faculty of Social Sciences. It was created by second-year students under the supervision of Dr. Nataša Logar and Dr. Erik Kopač. The starting point for the selection of terms was the Military Doctrine (2006) and the Military Logistics Doctrine (2008). The dictionary consists of 192 terms with definitions and English equivalents. The dictionary is distributed in XML using the TBX (TermBase eXchange) standard for representing and exchanging information from termbases