УСТОЙЧИВОСТ НА ОБРАЗЦИ ЛЕЩА КЪМ ФУЗАРИЙНО УВЯХВАНЕ (FUSARIUM OXYSPORUM F.SP. LENTIS)

Lentil (Lens culinaris Medic.) is one of the oldest known protein-rich food legumes. Lentil is the second pulse crop after dry bean in Bulgaria. Diseases such as Ascochyta blight and Lentil wilt play a major role in reducing lentil yield. Thirty two lentil genotypes with different geographical origin were screened for reaction to Fusarium oxysporum f.sp. lentis during 2003-2004 from the Institute for Plant Genetic Resourses, Sadovo under greenhouse conditions. Three of the studied accessions (91-001, 91-028 and 98-001) were susceptible with 45 and 50 % of total wilted plant.Лещата (Lens culinaris Medic.) е една от най-старите зърнено бобови култури богати на протеин. Болести като чернилка /Ascochyta blight/ и фузарийно увяхване /Fusarium oxysporum f.sp. lentis/ играят важна роля в редуциране добива при тази култура. Тридесет и два образци с различен географски произход бяха изпитани срещу причинителя на фузарийното увяхване. Изследването се проведе през 2003-2004 при условията на изкуствен инфекциозен фон. Три от образците (91-001, 91-028 и 98-001) представляват интерес за включване в селекционния процес

Econometric Methods and Monte Carlo Simulations for Financial Risk Management

Value-at-Risk (VaR) forecasting in the context of Monte Carlo simulations is evaluated. A range of parametric models is considered, namely the traditional Generalized Autore- gressive Conditional Heteroscedasticity (GARCH) model, the exponential GARCH and the GJR-GARCH, which are put in the context of the Gaussian and Student-t distri- butions. The returns of the S&P 500 provide the basis for the study. Monte Carlo simulations are then applied in the estimation and forecasting of index returns. Two forecasting periods are employed with respect to the Global Financial Crisis (GFC). The forecasting accuracy of the various models will be evaluated in order to determine the applicability of these VaR estimation techniques in dierent market conditions. Results reveal that: (i) no model has consistent performance in both volatile and stable mar- ket conditions; (ii) asymmetric volatility models oer better performance in the post crisis forecasting period; (iii) all models underestimate risk in highly unstable market conditions

Predicting Corporate Defaults: Evaluating Moody's Credit Rating Institute

The ability of the Merton model and the logistic regression to accurately forecast corporate defaults is evaluated. Additionally, the probability-of-default (PD) estimates obtained from these two models are compared with the corresponding rating class historic default rates presented by Moody’s. Data for 56 defaulted and 272 healthy US publicly traded organizations serves as the basis for this study. Results reveal that: (i) the logistic regression is more accurate in distinguishing between defaulted and healthy companies, but provides overly conservative PD estimates; (ii) the Merton model struggles to correctly identify true defaults and true non-defaults, while providing default probabilities that are in line with historic default rates (iii) no framework was deemed superior in this context, ascertaining the difficulty associated with identifying the precise timing of a corporate default

3D Printed Walking Robot Based on a Minimalist Approach

3D printing technology enables the design and testing of highly complex robot prototypes and joints. Here an original idea for a walking robot is presented, based on a minimalist approach. Although the robot has a simple mechanical structure using only 2 motors, it can walk, turn around its central axis and climb high obstacles. The simple design ensures higher reliability in terms of mechanics and control. A design principle is suggested, which minimizes power consumption during climbing. The kinematics and static conditions for overcoming an obstacle are analyzed and the movements of the robot are simulated. A 3D-printed prototype of the robot is created. It is used for experiments to test the efficiency of different materials and shapes for the robot’s feet when climbing. The results are ranked and compared with the efficiency of other walking robots

The distribution of class groups of function fields

Using equidistribution results of Katz and a computation in finite symplectic groups, we give an explicit asymptotic formula for the proportion of curves C over a finite field for which the l-torsion of Jac(C) is isomorphic to a given abelian l-group. In doing so, we prove a conjecture of Friedman and WashingtonComment: To appear, JPA

PHYSIOLOGICAL CHANGES IN BEAN (PHASEOLUS VULGARIS L.) LEAVES, INFECTED BY THE MOST IMPORTANT BEAN DISEA

Gas-exchange, plastid pigments and some other physiological parameters were determined in bean (Phaseolus vulgaris L. local populations) leaves naturally infected by Xanthomonas campestris pv.phaseoli (Smith) Dye, and Pseudomonas syringae pv.phaseolicola (Bukholder) Young, Dye et Wilkie, and in healthy leaves (control). It was established that infected leaves had lower both plastid pigments content and photosynthetic activity as well as lower yield and quality of produce

The integral monodromy of hyperelliptic and trielliptic curves

We compute the \integ/\ell and \integ_\ell monodromy of every irreducible component of the moduli spaces of hyperelliptic and trielliptic curves. In particular, we provide a proof that the \integ/\ell monodromy of the moduli space of hyperelliptic curves of genus $g$ is the symplectic group \sp_{2g}(\integ/\ell). We prove that the \integ/\ell monodromy of the moduli space of trielliptic curves with signature $(r,s)$ is the special unitary group \su_{(r,s)}(\integ/\ell\tensor\integ[\zeta_3])

Application of Statistical Methods for Evaluation of Local Phaseolus vulgaris L. Experimental Data

Beans are a traditional crop grown almost anywhere in the country. The local forms are well adapted to specific agro-climatic conditions in the growing areas and are an interesting initial material for selection programs. The aim of the study is the implementation of statistical methods for evaluation of genetic diversity in the local Phaseolus vulgaris L. collection and to indicate correlation relationships between the studied parameters and economical characteristics. The included genotypes were collected from expeditions by bilateral cooperation project with China. The experiment was conducted in the vegetable field of IPGR, Sadovo. Plants are characterized by quantitative and qualitative indicators, according to the International descriptor of IBPGRI (1982). The results indicate genetic diversity in the studied collection and correlation relationships between the studied parameters and yield per plant

Effect of the Predecessor and the Nitrogen Rate on Productivity and Essential Oil Content of Coriander (Coriandrum sativum L.) in Southeast Bulgaria

Received: May 31st, 2022 ; Accepted: August 13th, 2022 ; Published: September 19th, 2022 ; Correspondence: [email protected] (Coriandrum sativum L.) is one of the most important essential oil crops on a global scale. Coriander productivity is determined by the genotype, the environmental factors, as well the agronomic practices. A field experiment was conducted in Southeast Bulgaria during three vegetation seasons (2015, 2016, and 2017). The present study aimed at analysing the influence of two crop predecessors (winter wheat and sunflower) and four nitrogen (N) levels (0, 40, 80, and 120 kg ha-1 ). Productivity elements, seed yield, and seed essential oil content of coriander (cv. Mesten drebnoploden) were under evaluation. The results obtained showed that winter wheat was a more suitable predecessor of coriander in comparison to sunflower. The highest results regarding the number of umbels per plant, the umbel’s diameter, the number of umbellets per umbel, the number of seeds per umbel, the seed weight per plant, the 1,000 seed mass, as well as the seed yield for the rate of 80 kg ha-1 of N were recorded. The highest essential oil content after applying 120 kg ha-1 of N was established. Increasing the N level from 0 to 120 kg ha-1 led to a positive and significant effect on essential oil yield. No significant differences between the N rates of 80 and 120 kg ha-1 were recorded. The received results contributed for the evaluatation of the optimum nitrogen level, as well as for the determination of a more suitable predecessor of coriander in order to obtain the highest yield of better quality in the region of Southeast Bulgaria

Orthopedic Bone Drilling Robot ODRO: Basic Characteristics and Areas of Applications

The orthopedic manipulation “bone drilling” is the most executed one in the orthopedic surgery concerning the operative treatment of bone fractures. The drilling process is characterized by a number of input and output parameters. The most important input parameters are the feed rate [mm/s] and the drill speed [rpm]. They play significant role for the final result (the output parameters): thermal and mechanical damages of the bone tissue as well as hole quality. During the manual drilling these parameters are controlled by the surgeon on the base of his practical skills. But the optimal results of the manipulations can be assured only when the input parameters are under control during an automatic execution of the drilling process. This work presents the functional characteristics of the handheld robotized system ODRO (Orthopedic Drilling Robot) for automatic bone drilling. Some experimental results are also shown. A comparison is made between the similar systems which are known in the literature, some of which are available on the market. The application areas of ODRO in the orthopedic surgery practice are underlined