16 research outputs found
Investigation of selected independent variables on extrusion of rice semolina with and without propeller
The influence of screws with and without propeller, as well as the independent variables of material moisture content, working screw speed, feeding screw speed and die temperature on the changes of some physical and mechanical properties during singles-screw extrusion of rice semolina was studied. The response surface methodology was used with an orthogonal central composite design. Optimum modes of operation which lead to the maximization of the mass flow rate and the sectional expansion index and the minimization of the specific mechanical energy were established. The obtained results show that the use of a propeller in single-screw extrusion leads to an increase in extruder mass flow rate, a decrease in the specific mechanical energy and an increase in the sectional expansion index
Elemental speciation by capillary electrophoresis with inductively coupled plasma spectrometry: A new approach by flow focusingÂź nebulization
A novel system for Capillary Electrophoresis (CE) and Inductively Coupled Plasma (ICP) sample introduction that incorporates a dedicated Flow-FocusingÂź based nebulizer as aerosol generation unit is presented, aiming to provide high signal sensitivity and low detection limits for element speciation at short analysis times. To prove its viability, the system prototype constructed has been coupled to an inductively coupled plasma - optical emission spectrometer (ICP-OES) and an inductively coupled plasma - mass spectrometer (ICP-MS) for Cr(III) and Cr(VI) speciation. Separation - nebulization system and operation parameters (i.e., capillary length, nebulizer geometry, carrier flow, carrier ionic strength, separation potential and sample injection volume) have been considered and studied, and the analytical figures of merit obtained for model samples in ICP-MS are presented. The results obtained show that the developed instrumental system permits Cr speciation in less than two minutes with detection limits of 0.1, 0.2 and 0.03 ÎŒg/L for Cr(III), Cr(VI) and total Cr, respectively.The authors are grateful to the Spanish Government (project CTQ2008-06730-C02-01), the Valencian Government (project ACOMP/2010/047), the NSF of Bulgaria (project DO 02-07 GAMMA) and the European Commission (EC FP7 24588 BioSupport project) for the financial support
ANALYSIS OF POSTOPERATIVE PAIN AFTER EXTRACTION OF IMPACTED MANDIBULAR THIRD MOLARS AND ADMINISTRATION OF PREEMPTIVE ANALGESIA
patients because of the effect of pain symptoms on the healing process and quality of life. The objective of this study is to make a quantitative and qualitative assessment of the postoperative pain in patients to whom preemptive analgesia was administered.
Material and Methods: This is a randomised, placebo-controlled study in 80 patients who underwent surgical removal of impacted mandibular third molars. The patients were divided into three groups â with the preemptive administration of placebo, metamizole sodium and nimesulide. The short form of the McGill Pain Questionnaire (SF-MPQ) and the Visual Analogue Scale (VAS) were used for assessment and analysis of postoperative pain.
Results: For the first 24 hours after molar extraction the comparison of the values of the various pain components showed a superior effect of the preemptive analgesia with nimesulide for the alleviation of sensory and total pain compared to metamizole sodium and placebo. In all three groups, pain intensity was highest at postoperative hour 6.
Conclusion: Preemptive use of NSAIDs in the extraction of impacted mandibular third molars reduces the perception of postoperative pain and its intensity
CBCT images: an important tool in the analysis of anatomical variations of maxillary sinus related to Underwood septa features
The lack of prior information on the presence of Underwood septa is the most common anatomical cause of Schneider's membrane perforation during maxillary sinus floor elevation with lateral access. The objective of this study was to assess the incidence of Underwood septa, their location, type (primary or secondary) and height in Bulgarian patients. Cone beam computed tomography (CBCT) images of 200 patients were examined for the presence of Underwood septa. Presence of at least one septum was found in 144 patients. The non-parametric statistical MannâWhitney U-test and Fisher's exact test were used. No statistically significant differences were found between the two genders in terms of the presence of septa. In toothed patients, the location of the septa was behind the distal surface of the second molar in 57% of the cases. In patients with edentulous distal portions of the maxilla, location of the septa in the areas above the first premolar was seen in 54% of the cases. Depending on the presence of teeth, primary complete septa were found in toothed patients, and secondary partial septa were observed in edentulous patients. Prevalence of sagittal primary orientation was found in toothed patients (63%), while axial primary orientation of the septa was found in edentulous patients (58%). The obtained results suggest that precise determination of the septum orientation by CBCT would facilitate the correct choice of surgical approach to minimize the risk of Schneider's membrane perforation
Investigation of selected independent variables on extrusion of rice semolina with and without propeller
The influence of screws with and without propeller, as well as the independent variables of material moisture content, working screw speed, feeding screw speed and die temperature on the changes of some physical and mechanical properties during singles-screw extrusion of rice semolina was studied. The response surface methodology was used with an orthogonal central composite design. Optimum modes of operation which lead to the maximization of the mass flow rate and the sectional expansion index and the minimization of the specific mechanical energy were established. The obtained results show that the use of a propeller in single-screw extrusion leads to an increase in extruder mass flow rate, a decrease in the specific mechanical energy and an increase in the sectional expansion index
Correlation between Bone Mineral Density and Progression of Hip Osteoarthritis in Adult Men and Women in Bulgaria—Results from a 7-Year Study
Changes in clinical presentation, radiographic progression (RP), bone mineral density (BMD), bone turnover (BT), and cartilage turnover (CT) markers were compared in two groups of patients with hip osteoarthritis (HOA) over a period of 7 years. Each group consisted of 150 patients, including a control group on standard-of-care therapy (SC) with simple analgesics and physical exercises, and a study group (SG) on standard-of-care therapy supplemented by vitamin D3 and intravenous administration of zoledronic acid (5 mg) yearly for 3 consecutive years. Patient groups were homogenized regarding the following: (1) radiographic grade (RG), including 75 patients with hip OA RG II according to the Kellgren–Lawrence grading system (K/L), and 75 with RG III on K/L; (2) radiographic model (RM), as each of the K/L grades was subdivided into three subgroups consisting of 25 patients of different RMs: atrophic (‘A’), intermediate (‘I’), and hypertrophic (‘H’); (3) gender-equal ratio of men and women in each subgroup (Female/Male = 15/10). The following parameters were assessed: (1) clinical parameters (CP), pain at walking (WP-VAS 100 mm), functional ability (WOMAC-C), and time to total hip replacement (tTHR); (2) radiographic indicators(RI)—joint space width (JSW) and speed of joint space narrowing (JSN), changes in BMD (DXA), including proximal femur (PF-BMD), lumbar spine (LS-BMD), and total body (TB-BMD); (3) laboratory parameters (LP)—vitamin D3 levels and levels of BT/CT markers. RV were assessed every 12 months, whereas CV/LV were assessed every 6 months. Results: Cross-sectional analysis (CsA) at baseline showed statistically significant differences (SSD) at p < 0.05 in CP (WP, WOMAC-C); BMD of all sites and levels of CT/BT markers between the ‘A’ and ‘H’ RM groups in all patients. Longitudinal analysis (LtA) showed SSD (p < 0.05) between CG and SG in all CP (WP, WOMAC-C, tTHR) parameters of RP (mJSW, JSN), BMD of all sites, and levels of CT/BT markers for all ‘A’ models and in 30% of ‘I’-RMs (those with elevated markers for BT/CT at baseline and during the observation period). Conclusion: The presence of SSD at baseline (‘A’ vs. ‘H’) supported the thesis that at least two different subgroups of HOA exist: one associated with ‘A’ and the other with ‘H’ models. D3 supplementation and the intravenous administration of bisphosphonate were the treatment strategies that slowed down RP and postponed tTHR by over 12 months in the ‘A’ and ‘I’ RM with elevated BT/CT markers
Correlation between Bone Mineral Density and Progression of Hip Osteoarthritis in Adult Men and Women in BulgariaâResults from a 7-Year Study
Changes in clinical presentation, radiographic progression (RP), bone mineral density (BMD), bone turnover (BT), and cartilage turnover (CT) markers were compared in two groups of patients with hip osteoarthritis (HOA) over a period of 7 years. Each group consisted of 150 patients, including a control group on standard-of-care therapy (SC) with simple analgesics and physical exercises, and a study group (SG) on standard-of-care therapy supplemented by vitamin D3 and intravenous administration of zoledronic acid (5 mg) yearly for 3 consecutive years. Patient groups were homogenized regarding the following: (1) radiographic grade (RG), including 75 patients with hip OA RG II according to the KellgrenâLawrence grading system (K/L), and 75 with RG III on K/L; (2) radiographic model (RM), as each of the K/L grades was subdivided into three subgroups consisting of 25 patients of different RMs: atrophic (âAâ), intermediate (âIâ), and hypertrophic (âHâ); (3) gender-equal ratio of men and women in each subgroup (Female/Male = 15/10). The following parameters were assessed: (1) clinical parameters (CP), pain at walking (WP-VAS 100 mm), functional ability (WOMAC-C), and time to total hip replacement (tTHR); (2) radiographic indicators(RI)âjoint space width (JSW) and speed of joint space narrowing (JSN), changes in BMD (DXA), including proximal femur (PF-BMD), lumbar spine (LS-BMD), and total body (TB-BMD); (3) laboratory parameters (LP)âvitamin D3 levels and levels of BT/CT markers. RV were assessed every 12 months, whereas CV/LV were assessed every 6 months. Results: Cross-sectional analysis (CsA) at baseline showed statistically significant differences (SSD) at p p < 0.05) between CG and SG in all CP (WP, WOMAC-C, tTHR) parameters of RP (mJSW, JSN), BMD of all sites, and levels of CT/BT markers for all âAâ models and in 30% of âIâ-RMs (those with elevated markers for BT/CT at baseline and during the observation period). Conclusion: The presence of SSD at baseline (âAâ vs. âHâ) supported the thesis that at least two different subgroups of HOA exist: one associated with âAâ and the other with âHâ models. D3 supplementation and the intravenous administration of bisphosphonate were the treatment strategies that slowed down RP and postponed tTHR by over 12 months in the âAâ and âIâ RM with elevated BT/CT markers
PD-L1 positive lympho-epithelial lesions in inflammatory prostate
Objectives. Ductal epithelial changes
(lympho-epithelial lesions-LEL) in prostatic chronic
inflammation (CI) are not well studied so far.
Aim. To investigate LEL immediately adjacent to
prostatic CI.
Methods. We studied LEL in 144 prostatic surgical
and autopsy specimens in various types of prostatic CI:
NIH-category IV prostatitis (histologic prostatitis-HP),
nonspecific granulomatous prostatitis (NSGP), and the
reactive lymphoid infiltrates in the vicinity of benign
prostatic hyperplasia (BPH) and prostate adenocarcinoma (PCa). CI is scored as low and high grade
(LG, HG) according to the severity of inflammation.
Results. LEL was identified in all types of prostatic
specimens and in all types of prostatic CI: in 70.9% of
patients with HP; in 100% of cases with NSGP; in
68.7% and in 80% adjacent to BPH and PCa
respectively. Statistical analysis showed a significant
correlation of the presence of LEL with HG CI
(p<0.001). LEL showed strong membranous PD-L1
expression.
Conclusions. The study presents the first attempt to
examine LEL in inflammatory human prostate. PD-L1
positive LEL have no diagnostic organ specificity,
although they are a constant histological finding in HG
prostatic CI. LEL, inducible after birth by CI, are an
integral part of prostate-associated lymphoid tissue
(PALT) and of the inflammatory prostatic
microenvironmen
MSIS-ĐP-ĐĐS determination of As and Sb in complex matrices by magnetic nanoparticles-assisted hydride generation
The advantages of the microwave plasma atomic emission spectrometry (MP-AES) for hydride generation (HG) by means of modified Multi Mode Sample Introduction System (MSISÂź) have been revealed for analysis of As and Sb in complex real samples. Two main outcomes have been achieved: (i) reliable analysis and higher tolerability to less diluted matrices and (ii) a multifold reduction in the methodological limits of detection (MLOD). For the first time in real samples analysis the HG is assisted by silica-coated magnetic nanoparticles (MNPs) (âŒ2 mg mLâ1 MnFe2O4@SiO2) added to the hydrogenation reagent stream (1.5% NaBH4). This innovative approach provides smooth hydrides generation from problematic matrices, better gasâliquid separation and steady gas transport from the MSIS chamber. The effect is due to the elimination of NaBH4 delivery interruptions, the foam suppression in the reactor and levelling the carbon amount carried to the MP. The used inert MNPs could be collected from the drain with a permanent magnet and appear to be recyclable and reusable without memory effect or efficiency loss. The achieved benefits are demonstrated in the determination of As and Sb in three types of complex matrices: industrial electrolyte with high dissolved solids content, human urine prone to intensive foam creation, and sparkling mineral water releasing CO2.The work was supported by NSF of Bulgaria, Project DN19/9 2017â2021 (INISA)
SERUM YKL-40 LEVELS IN CHRONIC HEART FAILURE.
Inflammatory processes are involved in the pathogenesis and development of chronic heart disease. The promising novel inflammatory biomarker YKL-40 is related to the degree of inflammation and pathological tissue remodeling.
The aim of this study was to determine serum YKL-40 levels in patients with chronic heart failure and to evaluate the potential relationship with ultrasonography findings.
Forty-three individuals were enrolled in the study â 24 patients (10 females and 14 males) with chronic heart failure, aged 70±11 (mean ± standard deviation) and 16 healthy people as age-matched controls (above 50 years). The serum YKL-40 levels were assessed by ELISA. Sonographic measurements such as two-dimensional, Power wave, Continuous Wave, Colour mode and M-Mode were performed using a diagnostic ultrasound system (PHILIPS Ultrasound, Washington, US) with a L11-3 probe of 3-11 MHz. The six minute walk test was used to assess functional capability of patients.
Our study revealed significantly higher serum YKL-40 levels in patients compared to the control group (P=0.010). No relation was found between the glycoprotein and the results from the ultrasonographic and functional examination.
We suppose that increased serum YKL-40 levels in patients with chronic heart failure might reflect the inflammatory route in the development of the disease