Relative-coordinate determination for visual double stars by applying Fourier transforms

We discuss the software developed for the purpose of determining the relative coordinates (position angle θ and separation ρ) for visual double or multiple stars. It is based on application of Fourier transforms in treating CCD frames of these systems. The objective was to determine the relative coordinates automatically to an extent as large as possible. In this way the time needed for the reduction of many CCD frames becomes shorter. The capabilities and limitations of the software are examined. Besides, the possibility of improving is also considered. The software has been tested and checked on a sample consisting of CCD frames of 165 double or multiple stars obtained with the 2m telescope at NAO Rozhen in Bulgaria in October 2011. The results have been compared with the corresponding results obtained by applying different software and the agreement is found to be very good

The Closing-in phenomenon: intricate aspect of constructional apraxia

Fenomen približavanja modelu odnosi se na tendenciju da se zadati model kopira njemu veoma blizu ili preko njega. Ovaj fenomen klasično se shvata kao vid konstrukcione apraksije koji se javlja pri zadacima grafomotornog kopiranja ili pri gestualnim imitacijama. Njegovo ispoljavanje na neuropsihološkim testovima uzima se kao neurokognitivni indikator demencija, a najčešće kao indikator Alchajmerove demencije. Međutim, iako visoko specifičan znak za ovu vrstu demencije, savremena literatura upućuje na zaključak da ovaj fenomen svakako nije patognomoničan za Alchajmerovu bolest, već da se javlja u širokom spektru neurokognitivnih poremećaja sa ili bez demencije. Iako je naša stručna javnost upoznata sa fenomenom približavanja modelu, do sada se o njemu nije na sistematičan način izlagalo. Iz tog razloga, osim diskusije o značaju približavanja modelu u kliničkoj praksi, rad objedinjuje i kritički analizira dosadašnja saznanja u vezi sa fenomenom. U radu autori diskutuju: (1) Istorijski razvoj i konceptualizacija fenomena; (2) Neuroanatomski korelati fenomena; (3) Hipoteza o kompenzaciji; (4) Hipoteza o atrakciji.The closing-in phenomenon occurs when a drawing is reproduced close to or superimposed on the original model. This phenomenon is classically understood as a type of constructional apraxia that occurs during graphomotor copying tasks or gestural imitations. Its manifestation on neuropsychological tests is taken as a neurocognitive indicator of dementia, most often as an indicator of Alzheimer's disease. Although a highly specific sign for this dementia type, current literature suggests that it is certainly not pathognomonic for Alzheimer's dementia, but occurs in a wide range of neurocognitive disorders with or without dementia. Although the Serbian academic circles are familiar with this phenomenon, thus far it hasn’t been sistematically explored. For this reason, in addition to discussing the significance of this phenomenon in clinical practice, in this paper we also summarize and critically analyze current knowledge regarding closing-in phenomenon. In this paper we discuss: (1) Historical development and conceptualization; (2) Neuroanatomical correlates of the phenomenon; (3) Compensation hypothesis; (4) Attraction hypothesis

The Closing-in phenomenon: intricate aspect of constructional apraxia

Fenomen približavanja modelu odnosi se na tendenciju da se zadati model kopira njemu veoma blizu ili preko njega. Ovaj fenomen klasično se shvata kao vid konstrukcione apraksije koji se javlja pri zadacima grafomotornog kopiranja ili pri gestualnim imitacijama. Njegovo ispoljavanje na neuropsihološkim testovima uzima se kao neurokognitivni indikator demencija, a najčešće kao indikator Alchajmerove demencije. Međutim, iako visoko specifičan znak za ovu vrstu demencije, savremena literatura upućuje na zaključak da ovaj fenomen svakako nije patognomoničan za Alchajmerovu bolest, već da se javlja u širokom spektru neurokognitivnih poremećaja sa ili bez demencije. Iako je naša stručna javnost upoznata sa fenomenom približavanja modelu, do sada se o njemu nije na sistematičan način izlagalo. Iz tog razloga, osim diskusije o značaju približavanja modelu u kliničkoj praksi, rad objedinjuje i kritički analizira dosadašnja saznanja u vezi sa fenomenom. U radu autori diskutuju: (1) Istorijski razvoj i konceptualizacija fenomena; (2) Neuroanatomski korelati fenomena; (3) Hipoteza o kompenzaciji; (4) Hipoteza o atrakciji.The closing-in phenomenon occurs when a drawing is reproduced close to or superimposed on the original model. This phenomenon is classically understood as a type of constructional apraxia that occurs during graphomotor copying tasks or gestural imitations. Its manifestation on neuropsychological tests is taken as a neurocognitive indicator of dementia, most often as an indicator of Alzheimer's disease. Although a highly specific sign for this dementia type, current literature suggests that it is certainly not pathognomonic for Alzheimer's dementia, but occurs in a wide range of neurocognitive disorders with or without dementia. Although the Serbian academic circles are familiar with this phenomenon, thus far it hasn’t been sistematically explored. For this reason, in addition to discussing the significance of this phenomenon in clinical practice, in this paper we also summarize and critically analyze current knowledge regarding closing-in phenomenon. In this paper we discuss: (1) Historical development and conceptualization; (2) Neuroanatomical correlates of the phenomenon; (3) Compensation hypothesis; (4) Attraction hypothesis

Level of education and cerebral small vessel disease

Bolest malih krvnih sudova mozga (BMKS) je odgovorna za najveći broj možda- nih udara i vaskularno kognitivno oštećenje i obično je posledica klasičnih vaskularnih faktora rizika. Cilj našeg rada je da se u kohorti bolesnika sa BMKS ispita povezanost stepena obrazovanja i kliničke i radiološke sli- ke BMKS. U studiji je analizirano 424 ispitanika, srednje životne dobi od 62 godine, 53% muškog pola, različitog stepena obrazovanja u trajanju od 8 do 20 godina. Pokazana je statistički značajna povezanost stepena obrazovanja sa postojanjem simptoma depresije (p=0,050), ukupnom težinom lezija na MR moz- ga (p=0,029), kao i ukupnim brojem izolovanih lakunarnih ishemija (p=0,032). Zabeležena je povezanost pola (p=0,055) i lezija u periventrikularnoj regiji (p=0,062) sa stepenom obrazovanja na nivou statističkog trenda. Mehanizmi kojima stepen obrazovanja može uticati na rizik za nastanak vaskular- nih lezija mozga nisu u potpunosti razjašnjenji. Deo ove povezanost se može objasniti nižim socijalno-ekonomskim statusom, povećanom učestalošću vaskularnih bolesti (hipertenzija, dijabetes) i nezdravim navikama (pušenje, visokokalorijska ishrana, sedentarni način života), ali postoje dokazi da je ova korelacija nezavisna od klasičnih vaskularnih faktora rizika. Otkrivanje i rano korigovanje preventibilnih faktora za nastanak vaskularnih lezija mozga od velikog je društvenog značaja, uz potencijal da rane socijalne i eduka- tivne intervencije pozitivno utiču na status cerebralne cirkulacije kasnije u životu.Cerebral small vessel disease (CSVD), the most frequent cause of stroke and vascular cognitive impairment, is typically associated with common vascular risk factors. Our paper aims to analyze the correlation between the level of education and clinical and radiological presentation in a cohort of patients with CSVD. A total of 424 patients have been recruited, with a mean age of 62 years, 53% males, with years of education ranging from 8 to 20. We found a statistically significant correlation between depressive symptoms (p=0.050), total severity of cerebral lesions on MR scans (p=0.029), and the total number of lacunar ischemic lesions (p=0.032). The correlation between sex (p=0.055) and periventricular lesions (p=0.062) with educational status was at the level of the statistical trend. The putative mechanisms of the association between education and the risk for vascular brain lesions were not fully elucidated. Partially, this association can be explained by lower socioeconomic status, increased incidence of vascular diseases (hypertension, diabetes), and unhealthy lifestyle (smoking, poor diet, sedentary lifestyle), however, this association might also be independent of common vascular risk factors. Identification and early management of preventable risk factors for cerebral vascular lesions are of most importance to society, with the potential of early social and educational intervention to positively affect cerebral circulation status later in life

Level of education and cerebral small vessel disease

Bolest malih krvnih sudova mozga (BMKS) je odgovorna za najveći broj možda- nih udara i vaskularno kognitivno oštećenje i obično je posledica klasičnih vaskularnih faktora rizika. Cilj našeg rada je da se u kohorti bolesnika sa BMKS ispita povezanost stepena obrazovanja i kliničke i radiološke sli- ke BMKS. U studiji je analizirano 424 ispitanika, srednje životne dobi od 62 godine, 53% muškog pola, različitog stepena obrazovanja u trajanju od 8 do 20 godina. Pokazana je statistički značajna povezanost stepena obrazovanja sa postojanjem simptoma depresije (p=0,050), ukupnom težinom lezija na MR moz- ga (p=0,029), kao i ukupnim brojem izolovanih lakunarnih ishemija (p=0,032). Zabeležena je povezanost pola (p=0,055) i lezija u periventrikularnoj regiji (p=0,062) sa stepenom obrazovanja na nivou statističkog trenda. Mehanizmi kojima stepen obrazovanja može uticati na rizik za nastanak vaskular- nih lezija mozga nisu u potpunosti razjašnjenji. Deo ove povezanost se može objasniti nižim socijalno-ekonomskim statusom, povećanom učestalošću vaskularnih bolesti (hipertenzija, dijabetes) i nezdravim navikama (pušenje, visokokalorijska ishrana, sedentarni način života), ali postoje dokazi da je ova korelacija nezavisna od klasičnih vaskularnih faktora rizika. Otkrivanje i rano korigovanje preventibilnih faktora za nastanak vaskularnih lezija mozga od velikog je društvenog značaja, uz potencijal da rane socijalne i eduka- tivne intervencije pozitivno utiču na status cerebralne cirkulacije kasnije u životu.Cerebral small vessel disease (CSVD), the most frequent cause of stroke and vascular cognitive impairment, is typically associated with common vascular risk factors. Our paper aims to analyze the correlation between the level of education and clinical and radiological presentation in a cohort of patients with CSVD. A total of 424 patients have been recruited, with a mean age of 62 years, 53% males, with years of education ranging from 8 to 20. We found a statistically significant correlation between depressive symptoms (p=0.050), total severity of cerebral lesions on MR scans (p=0.029), and the total number of lacunar ischemic lesions (p=0.032). The correlation between sex (p=0.055) and periventricular lesions (p=0.062) with educational status was at the level of the statistical trend. The putative mechanisms of the association between education and the risk for vascular brain lesions were not fully elucidated. Partially, this association can be explained by lower socioeconomic status, increased incidence of vascular diseases (hypertension, diabetes), and unhealthy lifestyle (smoking, poor diet, sedentary lifestyle), however, this association might also be independent of common vascular risk factors. Identification and early management of preventable risk factors for cerebral vascular lesions are of most importance to society, with the potential of early social and educational intervention to positively affect cerebral circulation status later in life

Characterization of sodium alginate/D-limonene emulsions and respective calcium alginate/D-limonene beads produced by electrostatic extrusion

In this study, calcium alginate beads immobilizing D-limonene (solid systems) have been manufactured starting from emulsions of this flavor in sodium alginate (liquid systems). The effects of alginate concentration (0.02 and 0.03 g/mL) and flavor content (5 and 10 % w/w) on viscosity, conductivity and stability of emulsions were investigated. The flavor droplets in emulsions are bigger as polymer solution is more concentrated and contains more of the flavor. When emulsions have been subjected to electrostatic extrusion and upon Na+-Ca2+ ion exchange, smaller (similar to 960 to similar to 1450 mm) and less spherical beads were obtained (sphericity factor 0.003-0.21) compared to beads produced by simple dripping technique (without electrostatic field). When wet beads were air dried, they shrunk less if they had higher content of the flavor. Novel mathematical model describing swelling kinetics of dried beads is developed. In this work, D-limonene was efficiently immobilized within Ca-alginate beads (immobilization efficiency similar to 50 to similar to 77%) and its thermal stability was confirmed by TG/MS analysis

Electronic Properties of BZT Nano-Ceramic Grades at Low Frequency Region

Barium zirconium titanate ceramics were prepared using solid state reactions of BaCO3, TiO2 and ZrO2 at elevated temperatures. The prepared BZT was mechanically activated in the planetary ball mill from 0-120 min to achieve different powder grades from micro- to nanosized particles. After the powder characterization by XRD and SEM the samples were pressed in disc shape and sintered at 1100 and 1200 °C in the air. The sintered samples were characterized by SEM. After that the silver epoxy electrodes were deposited on sintered disc samples. The disc samples capacitance and resistivity were measured in the low frequency region from 1 Hz to 200 kHz using a low frequency impedance analyzer. Sintering temperatures and powder grades were used as parameters. Finally, specific resistance ρ, dielectric permittivity (ε' + jε") and tgδ were obtained from the impedance measurements. The trends in electronic properties were analyzed: the relaxation effect of the space charge (inter-granular electric charges) vs. sintering temperature and ceramic grades. These show that mechanical activation has a significant effect on electrical properties, resulting in generally improved overall performance

Freeze versus Spray Drying for Dry Wild Thyme (Thymus serpyllum L.) Extract Formulations: The Impact of Gelatin as a Coating Material

Freeze drying was compared with spray drying regarding feasibility to process wild thyme drug in order to obtain dry formulations at laboratory scale starting from liquid extracts produced by different extraction methods: maceration, heat-, ultrasound-, and microwave-assisted extractions. Higher powder yield (based on the dry weight prior to extraction) was achieved by freeze than spray drying and lower loss of total polyphenol content (TPC) and total flavonoid content (TFC) due to the drying process. Gelatin as a coating agent (5% w/w) provided better TPC recovery by 70% in case of lyophilization and higher powder yield in case of spray drying by diminishing material deposition on the wall of the drying chamber. The resulting gelatin-free and gelatin-containing powders carried polyphenols in amount ~190 and 53-75 mg gallic acid equivalents GAE/g of powder, respectively. Microwave-assisted extract formulation distinguished from others by higher content of polyphenols, proteins and sugars, higher bulk density and lower solubility. The type of the drying process affected mainly position of the gelatin-derived -OH and amide bands in FTIR spectra. Spray dried formulations compared to freeze dried expressed higher thermal stability as confirmed by differential scanning calorimetry analysis and higher diffusion coefficient; the last feature can be associated with the lower specific surface area of irregularly shaped freeze-dried particles (151-223 µm) compared to small microspheres (~8 µm) in spray-dried powder.Preprint: [10.20944/preprints202105.0358.v1

Freeze vs. Spray Drying for Dry Wild Thyme (Thymus serpyllum L.) Extract Formulations: The Impact of Gelatin as a Coating Material

Freeze drying was compared with spray drying regarding feasibility to process wild thyme drugs in order to obtain dry formulations at laboratory scale starting from liquid extracts produced by different extraction methods: maceration and heat-, ultrasound-, and microwave-assisted extractions. Higher total powder yield (based on the dry weight prior to extraction) was achieved by freeze than spray drying and lower loss of total polyphenol content (TPC) and total flavonoid content (TFC) due to the drying process. Gelatin as a coating agent (5% w/w) provided better TPC recovery by 70% in case of lyophilization and higher total powder yield in case of spray drying by diminishing material deposition on the wall of the drying chamber. The resulting gelatin-free and gelatin-containing powders carried polyphenols in amount ~190 and 53-75 mg gallic acid equivalents GAE/g of powder, respectively. Microwave-assisted extract formulation was distinguished from the others by a higher content of polyphenols, proteins and sugars, higher bulk density and lower solubility. The type of the drying process mainly affected the position of the gelatin-derived -OH and amide bands in FTIR spectra. Spray-dried formulations compared to freeze-dried expressed higher thermal stability as confirmed by differential scanning calorimetry analysis and a higher diffusion coefficient; the last feature can be associated with the lower specific surface area of irregularly shaped freeze-dried particles (151-223 µm) compared to small microspheres (~8 µm) in spray-dried powder