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Logging on steep terrain in our country is dangerous and low productivity. It is carried out by manual felling of the trees with a chainsaw and transportation by ropeways to a tractor or truck road. In recent years, due to the lack of manpower, the extraction and removal of wooden materials with the harvester/forwarder system, which are equipped with a traction (supporting) winch with a rope anchored to a stump or tree, has become more and more widespread. In our country, on the territory of the GS Rila Monastery, logging has been carried out using this new technology for three years. The article discusses the possible technologies and slopes at which logging can be carried out, as well as the productivity and depth of the plains of the machine chains. [ABSTRACT FROM AUTHOR]

In the past years windthrows are common accidents in our forests. In case of such natural disturbances it is essential that logging of the damaged timber are conducted quickly to avoid subsequent damages such as insect attacks and the waste of wood raw material. This study is focused on the logging operations of two mountain harvesters (combined mobile machines of medium length and crane processor) Mounty 4000 with processor Woody H 50 and Koller K501 with processor Woody H 60. The observed productivity is 6,57 m3/h for Mounty 4000 and 7,29 m3/h for Koller K501 at an average diameter of 27,3 cm (without bark). The average relative productivity of one crane processor at average assortment diameter of 27-28 cm is 12 to 17 times higher than the productivity of a chainsaw operator. [ABSTRACT FROM AUTHOR]

The article presents the results of a study on the operation of the Mounty 4000 machine with the Woody H60 processor head in the mountainous conditions of Bulgaria. The structuring of the machine operation cycle was carried out and for each component the values of their durations were obtained in the course of a production experiment. This allows predicting the productivity of work, as well as the economic efficiency of using the “mountain harvester” in logging. In the course of the simulation experiment, the dependence of the damage of tree trunks left in the cutting area on the density of planting, the distance of skidding and the intensity of felling during the primary transportation of wood was established. This allows for a comprehensive assessment of the functioning of the Mounty 4000 machine simultaneously from economic and environmental points of view at the stage of technological design of logging operations.

The content of 12 essential and toxic elements (V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Mo, Pb) in Bulgarian forest fruits as bilberry (Vaccinium myrtillus), lingonberry (Vaccinium vitis-idaea), cornel (Cornus mas) and howthorn (Crataegus laevigata) was investigated. The highest content of Zn was found in cornels (10.67±0.04 mg kg-1), while the richest in Fe is lingonberry (37.1±0.3 mg kg-1), followed by the hawthorn (10.42±0.05 mg kg-1). Content of toxic metals (Pb, Ni) are in amount significantly below the permissible standards. The lowest content of total carbohydrates belongs to hawthorn (5.9±0.1%), while the highest in cornels (11.2±0.1%). The differences in metal content of the investigated fruits were proven by application of mathematical- statistical analysis. Discriminant analysis was used to define the fruit and to estimate the significance of individual indexes in modelling. Canonical variables, included by degree of importance in discriminant functions for examined group of wild edible fruits are Fe, Mn, Cu, and Zn. [ABSTRACT FROM AUTHOR]

Introduction: Drug addictions to psychoactive substances are disorders with a complex bio-psycho-social genesis, which are characterized with chronic relapses. Substance addiction causes multifactorial damage to the normal functioning of individuals and requires a multicenter approach for the treatment process.

Introduction: The objective of this study was to assess the diagnostic value of the "lever sign test" to diagnose ACL rupture and to compare this test to the two most commonly used, the Lachman and anterior drawer test., Method: This prospective study was performed in the ED of the Cliniques Universitaires Saint-Luc (Brussels, Belgium) from March 2017 to May 2019. 52 patients were included undergoing knee trauma, within 8 days, with an initial radiograph excluding a fracture (except Segond fracture or tibial spine fracture). On clinical investigation, patients showed a positive lever sign test and/or a positive Lachman test and/or a positive anterior drawer test. Exclusion criteria were a complete rupture of the knee extensor mechanism and patellar dislocation. All the physicians involved in this study were residents in training. An MRI was performed within 3 weeks for all included patients after the clinical examination. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were investigated for all three tests with MRI used as our reference standard., Results: Forty out of 52 patients suffered an ACL rupture (77%) and 12 did not (23%). The sensitivity, specificity, PPV and NPV of the lever sign test were respectively 92.5%, 25% 82% and 50%. Those of the Lachman test were 54%, 54.5%, 81% and 25%, and those of the anterior drawer test were 56%, 82%, 90.5% and 37.5%. Twelve out of 40 ACL ruptures (30%) were diagnosed exclusively with a positive lever sign test., Conclusion: When investigating acute ACL ruptures (< 8 days) in the ED, the lever sign test offers a sensitivity of 92.5%, far superior to that of other well-known clinical tests. The lever sign test is relatively pain-free, easy to perform and its visual interpretation requires less experience. Positive lever sign test at the ED should lead to an MRI to combine high clinical sensitivity with high MRI specificity., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Purpose: To compare the diagnostic performance of MRI and 18 F-FDG-PET/CT in detecting bone marrow involvement (BMI) in patients with multiple myeloma (MM)., Materials and Methods: This retrospective study was approved by our Institutional Review Board. Two radiologists and two nuclear medicine specialists independently and blindly reviewed 84 pairs of MRI and PET/CT scans obtained in 73 MM patients. Readers assessed the presence and patterns of BMI. The best valuable comparator (BVC) for BMI was established by a panel review of all baseline and follow-up imaging, and biological and pathological information. Intra- and inter-reader agreement and correlation between MRI and PET/CT were assessed using the prevalence-adjusted bias-adjusted kappa (k) coefficient. Diagnostic performance of MRI and PET/CT in detecting BMI was evaluated from ROC characteristics. Association between imaging and biological, pathological, and clinical findings was assessed using Wilcoxon rank-sum and chi-square tests., Results: Intra- and inter-reader agreement was very good for MRI (k = 0.90 [0.81; 1.00] and 0.88 [0.78; 0.98]). Intra- and inter-reader agreement was good for PET/CT (k = 0.80 [0.69; 0.91] and 0.71 [0.56; 0.86]). The sensitivity of MRI to detect BMI (97% [90%; 100%]) was significantly superior to that of PET/CT (76% [64%; 85%]) (p < 0.001). The specificity of MRI (86% [57%; 98%]) was lower than that of PET/CT (93% [66%; 100%]), without reaching statistical significance (p = 0.32). There was a strong correlation between decisions regarding patient management and PET/CT findings (p < 0.001)., Conclusion: MRI is significantly more sensitive than PET/CT to detect BMI in MM. Patient management is more strongly correlated with PET/CT findings., Key Points: • MRI and PET/CT have very close diagnostic value for the detection of bone marrow involvement in multiple myeloma. • MRI has a significantly higher sensitivity and better reproducibility. • PET/CT findings appear to have a higher impact on clinical decisions.

The aim of this work was to assess the risks and analyse the risk factors for development of chronic periodontitis in Bulgarian patients. The quality of life was investigated in a cohort of 228 patients with chronic periodontitis. Within the frame of this study, pilot research (a case-control study) was conducted among 80 patients (20 cases and 60 control patients without periodontitis) to evaluate the risk for development of chronic periodontitis. The minimum sample size of patients was determined based on power analysis for sample-size calculation. The mean age of participants in the control group was 31.33 ± 9.38 years and in the case group, 33.00 ± 11.52. Data were accumulated by clinical and sociological methods. Descriptive statistics and multi-factor logistic regression analysis (Backward Conditional procedure) were used. One-factor dispersion analysis showed that, of the 12 studied risk factors, the following variables were significant: stress, diabetes, presence of calculus, overlapping and misaligned teeth ( P < 0.05). Multiple logistic regressions were applied to evaluate the association between the variables. Three predictors were selected in the final logistic regression equation: diabetes ( B = 4.195; P = 0.001), crooked and overlapping teeth ( B = 3.022; P = 0.010) and stress ( B = 2.882; P = 0.014). The logistic risk assessment model for development of periodontitis has a predictive value of 93.80% (χ 2 = 63.91; P = 0.000). Our results confirmed some proven risk factors for periodontal disease. In the studied population, diabetes was the single, most important predictor for development of periodontitis.