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Steep terrain harvesting can only be implemented by a limited set of operational alternatives; therefore, it is important to be efficient in such conditions, in order to avoid incurring high costs. Harvesting abiotically-disturbed forests (salvage harvests caused by wet snow), which is becoming common these days, can significantly impact the operational efficiency of extraction operations. This study was implemented in order to evaluate the performance of truck-mounted uphill cable yarding operations in salvage logging deployed in coniferous stands. A time study was used to estimate the productivity and yarding costs, and predictive models were developed in order to relate the time consumption and productivity to the relevant operational factors, including the degree of wood damage. The average operational conditions were characterized by an extraction distance of 101 m and a lateral yarding distance of 18 m, resulting in a productivity rate of 20.1 m3 h−1. In response to different kind of delays, the productivity rate decreased to 12.8 m3 h−1. Under the prevailing conditions, lateral yarding accounted for 32% of the gross work cycle time, and for 50% of the delay-free work cycle time of the machine. Decreasing the lateral yarding distance and increasing the payload volume to the maximum capacity of the machine would eventually lead to a yarding productivity of close to 30 m3 per SMH (scheduled machine hour). The calculation of the gross costs of uphill yarding showed that the labor costs (35.7%) were slightly higher than the fixed costs (32.9%), and twice as high compared to the variable costs (17.7%). The remote control of the carriage, mechanical slack-pulling mechanisms, and radio-controlled chokers are just some of the improvements that would have led to increments in operational efficiency.

In addition to natural pine forests in Bulgaria, there are also large artificial plantations (over 1.5 million ha), created in the period of 1950–1990. Large areas with non-thinned coniferous plantations located at low altitudes are associated with a high probability of reduced growth and significant health problems. Traditionally, adapted agricultural tractors are the most widely used equipment for timber extraction in Bulgaria. The shortage of work force due to labor-intensive and unattractive logging work is one of the reasons for making efforts to introduce more advanced, multipurpose equipment. However, in Bulgaria the use of harvesters is limited by the predominance of deciduous forests, steep terrains and by the maximum allowed harvesting intensity of 30 %. The latter requirement often makes modern logging equipment unprofitable. In an attempt to overcome some of these limitations, the use of a combined wheeled skidder-harvester (SH) has been introduced in the eastern Rhodopes Mountains in the last few years. The SH works as a harvester and fells the accessible trees located on the skid roads and on the corridors. The remaining marked trees are felled manually by chainsaw. The felled trees are dragged to the machine by a two-drum winch equipped with a remote control, skidded to the landing where they are delimbed, bucked and piled by the SH. The mean productivity of the SH which stands for a mean skidding distance of 69 m, a mean bunching distance of 14 m, a mean load volume of 4.06 m3, was estimated at 9.38 m3·PMH-1 (8.27 m3·SMH-1) timber piled at landing, which is comparable to two typical logging teams with adapted tractors and 4–5 workers in each team. The gross costs per unit done by the SH (14.24 €·m-3) are within the regional level for coniferous stands.

In this article the basic rules for sclerotherapy of varicose veins in some special cases are discussed. These include varicose veins in pregnant women, sclerotherapy in patients against the background of treatment with indirect anticoagulants, in patients with pronounced postphlebitic syndrome, sclerotherapy of various gangliomas and the so-called accelerated sclerotherapy, as well as sclerotherapy of limbs with lipoedema and lymphedema.A thorough review of the main European schools working in this field—Swiss, French, German and Irish—has been carried out.The authors have summarized the experience of prominent sclerotherapists and give specific practical advice.

In this original article, the basic equipment and the principles of work organization in a medical practice designed for sclerosing treatment of varicose veins are presented to colleagues who perform such therapy of the lower extremities.Personal experience is shared, as well as the experience of numerous similar medical practices in different countries of the European Union.

Introduction: Primary varicose veins of the lower extremities mainly cover the great saphenous vein (VSM) and small saphenous vein (VSP) basins. The treatment procedure for pulse removal can be performed by a standard open technique—crossectomy and stripping, by minimally invasive methods—radiofrequency and laser ablation, as well as by internal application of a sclerosing agent in liquid or foam format. The use of foam began as far back as 1939.Literature Review: This publication examines in detail the historical stages that foam sclerotherapy has gone through from its inception to the present day. The rules for treatment with sclerosing high-viscosity foam, approved by phlebologists worldwide, are described in detail.Discussion: Foam sclerotherapy for various forms of varicose veins is a uniquely good and inexpensive method for radical treatment of superficial varicose veins. Even if the recurrence rate after foam sclerotherapy is slightly higher than other minimally invasive procedures, foam treatment is an affordable, inexpensive, and highly effective method, as long as it is performed according to the accepted rules.Conclusion: The present material considers the individual historical moments for establishing the foam treatment as a method of choice. John Bergan’s 2003 statement: “Foam is the future of varicose vein treatment,” is still relevant today.

Основната цел на дисертационния труд е да се анализират възможностите за оптимизиране прилагането на подхода ЛИДЕР в Р. България и повиши неговата ефективност. В дисертационния труд е направено теоретично изследване върху същността на ЛИДЕР, проучена е нормативно-институционалната рамка за изграждане и функциониране на МИГ/МГД като инструменти на ПРСР. Извършен е преглед на развитието и резултатите, които е постигнал ЛИДЕР в ЕС и в България. Изложени и анализирани са основните фактори, довели до влошената социално-икономическа среда в селските райони на България. Направена е характеристика на МИГ и е представен ретроспективен анализ на прилагането на подхода ЛИДЕР в България. Направена е оценка на изпълнението и въздействието на подхода ЛИДЕР върху местното развитие, като е извършена съпоставка между резултати, цели и ресурс. Въз основа на изготвен методически инструментариум е проведено анкетно проучване между МИГ, според което са установени основните проблеми, възможностите за оптимизация и значението на ЛИДЕР за развитието на районите. Изготвен е SWOT – анализ на МИГ в България и е предложен модел на организационната структура на управление на ЛИДЕР., The main purpose of dissertation work is to analyse the possibilities for optimizing the implementation of the LEADER approach in Bulgaria and increase its efficiency. In dissertation work, a theoretical study was made on the substance of LEADER, the regulatory and institutional framework for the construction and functioning of LAG/LAGS was studied as instruments of the RDP. A review of the development and results achieved by the LEADER in the EU and in Bulgaria was carried out. The main factors leading to the deteriorated socio-economic environment in Bulgaria's rural areas are exposed and analyzed. A characteristic of the LAG has been made and a retrospective analysis of the implementation of the LEADER approach in Bulgaria is presented. An evaluation of the implementation and impact of the LEADER approach on local development was carried out, comparing results, targets and resources. Based on a methodological toolkit, a survey was conducted between LAGS, according to which the main problems, the possibilities for optimization and the importance of LEADER for the development of the regions were identified. A SWOT-analysis of the LAG in Bulgaria was prepared and a model of the organizational structure of LEADER management is proposed.

Introduction: Primary varicose veins mainly cover the great saphenous vein (VSM) and the small saphenous vein (VSP) basins of the lower extremities. The treatment procedure for their removal, the so-called radical varicophlebectomy, can be performed by the standard open technique—crossectomy and stripping, by minimally invasive methods—radiofrequency and laser ablation, and by intralumenal application of a sclerosing agent.Literary Review: This publication details the possibility of obtaining a highly viscous foam, the route of administration into a varicose vein, and the subsequent additional treatment procedures. The rules for treatment with sclerosing of high-viscosity foam, which have been established at the end of 2006 by more than 30 world phlebologists, are described in detail.Discussion: Foam sclerotherapy of various forms of varicose veins is a uniquely good and inexpensive method for radical treatment of superficial varicose veins. Even if the recurrence rate after penosclerotherapy is slightly higher than in other minimally invasive treatments, foam treatment is an affordable, inexpensive, and highly effective method, as long as it is performed according to accepted rules.Conclusion: This material summarizes the positive results of foam sclerosing treatment performed according to clearly established rules.

Background concentrations of the heavy metals Mn, Ni, Cd, Co, Zn, Cu, and Pb in the soils and plant monitors of the Boatin Reserve were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Surface soil layers of the Boatin Reserve were polluted with Cu, as its concentration exceeded both the national legal standards and the content of Cu in non-polluted areas. Analysis of heavy metals accumulation in all studied plant monitors indicated that the content of Cu, Pb, and Zn exceeded their concentration in non-polluted areas. It may be concluded that the heavy metals Cu, Pb, and Zn are the main pollutants in the Boatin Reserve.

Polyacrylamide gel electrophoresis was employed to study the isoenzyme variation of esterase and acid phosphatase in natural populations of Dasypyrum villosum (L.) P.Candargy, Elytrigia repens (L.) Nevski and Elymus caninus (L.) L. Four similarity indices (SI, S, D, Ih) were calculated in an attempt to evaluate quantitatively genetic affinities among the species examined. Considering index D, the species D. villosum proved to be equally distant (D = 0.17 in both cases) from the species pair Et. repens and El. caninus. The nearly twice lower value of D for the comparison between Et. repens and El. caninus is an indication of their stronger genetic relationship. Mean values of indices Ih, SI and S also indicated that D. villosum is the most distinct species within the group studied. The results were discussed in the light of chloroplast DNA sequence data, suggesting a close affinity among the genera Dasypyrum (Coss. & L.Durieu) T.Durand, Elytrigia Desv. and Elymus L. The results of the present isoenzyme study are not in congruence with cpDNA analysis. Both isoenzyme and DNA data suggest that the phylogenetic position of the genus Dasypyrum within the tribe Triticeae remains unresolved.