109 research outputs found
Microstructure of kajmak skin layer made during kajmak production
No full textKajmak je jedinstven mliječni proizvod s dugom tradicijom u balkanskim zemljama i na Bliskom istoku. Pokožice kajmaka su formirane tijekom 60 minuta proizvodnje kajmaka, što utječe na kvalitetu i određuje strukturu konačnog proizvoda. U radu je istražen utjecaj sastava mlijeka i toplinske obrade (75-95 °C/5 min) na sastav, mikrostrukturu i raspodjelu proteina u pokožicama kajmaka. Mikrostruktura je određena pomoću skenirajuće elektronske mikroskopije (SEM), dok je raspodjela proteinskih frakcija proučavana pomoću SDS PAGE elektoroforeze u reducirajućim i nereducirajućim uvjetima. Pokožice kajmaka dobivene iz mlijeka tretiranog u uobičajenom režimu intenzivne toplinske obrade, karakteri¬zirane su s β-LG i α-LA prisutnim uglavnom u kompleksima povezanim disulfidnim vezama, dok je niža temperatura (75 °C) uzrokovala prisutnost proteina sirutke u dominantno pojedinačnom obliku. Jači tretmani mlijeka (85 °C, 90 °C i 95 °C) uzrokovali su potpuno uključivanje β-LG u komplekse, dok je određena količina α-LA pronađena kao monomer. Sastav pokožica, intenzitet primijenjene toplinske obrade mlijeka i agregirani proteini sirutke pokazali su vrlo jak utjecaj na mikrostrukturu pokožica. Mikrostruktura pokožica s niskim udjelom masti i omjerom F/P okarakterizirana je kompaktnom strukturom i zbijenim proteinskim matriksom. Visok udjel masti i omjer F/P rezultirali su dispergiranom mikrostrukturom s razvučenim proteinskim lancima. Mikrostrukture pokožica proizvedenih od mlijeka obogaćenog proteinima sirutke karakterizirane su vlaknastim, filamentoznim segmentima uslijed vezanih denaturiranih proteina sirutke, osobito vezanog β-LG.Kajmak is a unique dairy product with a long tradition in Balkan countries and the Middle East. Kajmak skin layers are formed during 60 minutes of kajmak production, influencing the quality and determining the structure of the final product. The influence of milk composition and heat treatments (75-95 °C/5min) on the composition, microstructure and protein distribution of kajmak skin layers was investigated in this study. Microstructure was determined using scanning electron microscopy (SEM), while the distribution of protein fractions was studied by SDS PAGE in reducing and non-reducing conditions. Kajmak skin layers obtained from milk treated at common intense heat regime were characterized with β-LG and α-LA mainly as disulfide-linked complexes, while lower temperature (75 °C) caused the presence of whey proteins in dominantly individual form. More severe treatments (85 °C, 90 °C and 95 °C) caused the full involvement of β-LG in the complexes, since a certain amount of α-LA was found as a monomer. The kajmak skin layer composition, severity of the applied milk heat treatment and the linked whey proteins exhibited a very strong influence on kajmak skin layer microstructure. The microstructure of kajmak skin layer with a low fat content and fat/protein (F/P) ratio was characterized by a compact structure with a dense protein matrix. High fat content and F/P ratio resulted in a dispersive form of the stretched protein network. Kajmak skin layers produced from milk with added whey proteins were characterized by fibrous, thread-like segments, due to the incorporated denatured whey proteins, especially linked β-LG
Parametri kvalitete kačkavalj sira u tipu pasta filata iz Srbije i procjena usklađenosti sa zakonskim kriterijima
No full textThe purpose of this study was to investigate the chemical, proteolysis, microbiological, colour and textural characteristics of Serbian Kačkavalj cheese in order to determine the variability degree between cheeses, compare their properties to other similar ‘Pasta Filata’ cheeses and to determine if they comply to the regulative requirements. A broad range of variations of cheese characteristics was found among Kačkavalj cheeses. The composition showed high variations: dry matter ranged from 51.52% to 58.71%; fat from 20.00% to 29.50%; fat in dry matter from 36.08% to 55.96%; NaCl from 0.93% to 3.69%; total protein from 23.25% to 30.79%. The proteolysis parameters in Kačkavalj cheeses differed significantly. The colour evaluation showed significant differences in a* and b* values, however in L* values there were no significant differences (p>0.05). The traditional Kačkavalj cheese represents the part of national heritage; thus, the comprehensive characterization was conducted to investigate quality variations between Serbian Kačkavalj cheeses. The study identified that term Kačkavalj is used despite some cheeses are not fully compliant with the National Standard. The control of fulfilling the requirements of the National Standard should be improved, as well as raising awareness and prevention of inadequate cheese labelling.Svrha ove studije bila je ispitati kemijska i mikrobiološka svojstva, boju, teksturu i stupanj proteolitičkih promjena srpskog kačkavalj sira kako bi se utvrdio stupanj varijabilnosti između sireva, usporedila njihova svojstva s drugim sličnim sirevima parenog tijesta i utvrdilo jesu li u skladu sa zakonski postavljenim kriterijima za ovu vrstu sira. Utvrđen je širok raspon varijacija između ispitivanih svojstava kačkavalj sireva. Sastav je ukazao na velike varijacije u udjelu ukupne suhe tvari koji se kretao od 51,52 % do 58,71 %, udjela mliječne masti od 20,00 % do 29,50 % i udjela masti u suhoj tvari od 36,08 % do 55,96 %, udjela NaCl od 0,93 % do 3,69 % te udjela ukupnih proteina od 23,25 % do 30,79 %. Parametri proteolize u sirevima kačkavalj značajno su se razlikovali. Ispitivanja boje pokazala su značajne razlike u vrijednostima a* i b*, međutim u vrijednostima L* nije bilo značajnih razlika (p>0,05). Tradicionalni sir kačkavalj predstavlja dio nacionalne baštine pa je stoga provedena sveobuhvatna karakterizacija kako bi se istražile varijacije kvalitete između kačkavalj sireva iz Srbije. Prema rezultatima studije, izraz kačkavalj se koristi iako neki sirevi nisu u potpunosti usklađeni s Nacionalnim standardom. Potrebno je unaprijediti kontrolu ispunjavanja zahtjeva Nacionalnog standarda, kao i podizanje svijesti i prevenciju neadekvatnog deklariranja sira
Time-Domain Measurement of Broadband Coherent Cherenkov Radiation
No full textWe report on further analysis of coherent microwave Cherenkov impulses emitted via the Askaryan mechanism from high-energy electromagnetic showers produced at the Stanford Linear Accelerator Center (SLAC). In this report, the time-domain based analysis of the measurements made with a broadband (nominally 1-18 GHz) log periodic dipole antenna (LPDA) is described. The theory of a transmit-receive antenna system based on time-dependent effective height operator is summarized and applied to fully characterize the measurement antenna system and to reconstruct the electric field induced via the Askaryan process. The observed radiation intensity and phase as functions of frequency were found to agree with expectations from 0.75-11.5 GHz within experimental errors on the normalized electric field magnitude and the relative phase; {sigma}{sub R|E|} = 0.039 {micro}V/MHz/TeV and {sigma}{sub {phi}} = 17{sup o}. This is the first time this agreement has been observed over such a broad bandwidth, and the first measurement of the relative phase variation of an Askaryan pulse. The importance of validation of the Askaryan mechanism is significant since it is viewed as the most promising way to detect cosmogenic neutrino fluxes at E{sub v} {ge} 10{sup 15} eV
Detection of milk fat adulteration with margarine and palm oil in kajmak
No full textKajmak is a milk fat-based dairy product that is very popular in the Balkans. However, it is
often the subject of adulteration. The aim of this study was to determine the detectable level
of adulteration of milk fat in kajmak with margarine and refined palm oil based on iodine value
analysis and fatty acid profile by gas chromatographic analysis. In addition, a texture analysis
of the adulterated kajmak samples was performed. Six treatments of adulterated kajmak were
prepared by mixing fresh kajmak with margarine and refined palm oil in proportions of 5 %, 10 %
and 20 % of the total fat in the kajmak. When comparing the fatty acid groups, the detectable
level of adulteration for both the added margarine and the palm oil was 10 %. The adulteration
of kajmak with 5 % margarine and refined palm oil can be detected by analysing the iodine
value as well as by measuring the proportion of trans fatty acids in the case of adulteration
with margarine or the C18:3 n-3 in kajmak adulterated with refined palm oil. Larger amounts of
added adulterants of 10 % and 20 % can be detected by measuring the proportion of most other
fatty acids. The textural properties, in particular firmness and spreadability, were statistically
significantly changed (p<0.05) when both margarine and refined palm oil were added, but only
in an amount of at least 20 %
Observation of Ultrahigh-Energy Cosmic Rays with the ANITA Balloon-Borne Radio Interferometer
No full textLight tracking through ice and water—Scattering and absorption in heterogeneous media with Photonics
No full textIn the field of neutrino astronomy, large volumes of optically transparent matter like glacial ice, lake water, or deep ocean water are used as detector media. Elementary particle interactions are studied using in situ detectors recording time distributions and fluxes of the faint photon fields of Cherenkov radiation generated by ultra-relativistic charged particles, typically muons or electrons. The Photonics software package was developed to determine photon flux and time distributions throughout a volume containing a light source through Monte Carlo simulation. Photons are propagated and time distributions are recorded throughout a cellular grid constituting the simulation volume, and Mie scattering and absorption are realised using wavelength and position dependent parameterisations. The photon tracking results are stored in binary tables for transparent access through ansi-c and c++ interfaces. For higher-level physics applications, like simulation or reconstruction of particle events, it is then possible to quickly acquire the light yield and time distributions for a pre-specified set of light source and detector properties and geometries without real-time photon propagation. In this paper the Photonics light propagation routines and methodology are presented and applied to the IceCube and Antares neutrino telescopes. The way in which inhomogeneities of the Antarctic glacial ice distort the signatures of elementary particle interactions, and how Photonics can be used to account for these effects, is described.</p
Patterns of Cortical Synchronization in Isolated Dystonia Compared With Parkinson Disease
No full textImportanceIsolated dystonia and Parkinson disease (PD) are disorders of the basal gangliothalamocortical network. They have largely distinct clinical profiles, but both disorders respond to deep brain stimulation (DBS) in the same subcortical targets using similar stimulation paradigms, suggesting pathophysiologic overlap. We hypothesized that, similar to PD, isolated dystonia is associated with elevated cortical neuronal synchronization.ObjectiveTo investigate the electrophysiologic characteristics of the sensorimotor cortex arm-related area using a temporary subdural electrode strip in patients with isolated dystonia and PD undergoing DBS implantation in the awake state.Design, setting, and participantsAn observational study recruited patients scheduled for DBS at the University of California, San Francisco and the San Francisco Veterans Affairs Medical Center. Data were collected from May 1, 2008, through April 1, 2015. Findings are reported for 22 patients with isolated cervical or segmental dystonia (8 with [DYST-ARM] and 14 without [DYST] arm symptoms) and 14 patients with akinetic rigid PD. Data were analyzed from November 1, 2014, through May 1, 2015.Main outcomes and measuresCortical local field potentials, power spectral density, and phase-amplitude coupling (PAC).ResultsAmong our 3 groups that together included 36 patients, cortical PAC was present in primary motor and premotor arm-related areas for all groups, but the DYST group was less likely to exhibit increased PAC (P = .008). Similar to what has been shown for patients with PD, subthalamic DBS reversibly decreased PAC in a subset of patients with dystonia who were studied before and during intraoperative test stimulation (n = 4). At rest, broadband gamma (50-200 Hz) power in the primary motor cortex was greater in the DYST-ARM and PD groups compared with the DYST group, whereas alpha (8-13 Hz) and beta (13-30 Hz) power was comparable in all 3 groups. During movement, the DYST-ARM group had impaired beta and low gamma desynchronization in the primary motor cortex.Conclusions and relevanceIsolated dystonia and PD have physiologic overlap with respect to high levels of motor cortex synchronization and reduction of cortical synchronization by subthalamic DBS, providing an explanation for their similar therapeutic response to basal ganglia stimulation
1469 RETROSPECTIVE, SINGLE-INSTITUTION COMPARISON OF RADICAL PROSTATECTOMY AND EXTERNAL-BEAM RADIATION THERAPY FOR HIGH-RISK PROSTATE CANCER
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