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Managing electric vehicles (EVs) charging activities when the power grid is congested is a challenging task. This article proposes a dynamic, real-time, demand-influenced energy pricing mechanism to accurately allocate fairness to the billing strategy of the EVs charging process. The proposed mechanism is based on the concept of the inverse-demand function to reflect instantaneous energy prices following the microgrids’ real-time energy supply. It comprises two pricing fractions: retail energy price representing the energy cost for non-EVs demand during peak hours, and congested energy price allocated for billing EVs charging events during congested timeslots. The proposed methodology is implemented in a hierarchal multiagent architecture with an optimal energy management system to provide a cost-efficient microgrid operation. The input to the optimization problem is stochastic models that represent day-ahead photovoltaic (PV) production forecast, EVs energy levels, and connectivity times’ prediction models based on a discrete-time Markov chain. Additionally, a predictive model of daily load is also proposed based on adaptive artificial neural networks. The aforementioned models utilized historical data for Miami-Dade County, South Florida. Through numerical simulations, we attest that the proposed pricing mechanism achieves significant energy price reduction for non-EVs consumers when compared with results from previously published pricing policies.

GC/MS of unsaponifiable matter (USM) of Ipomoea tricolor (Cav.) and Ipomoea fistulosa (Mart. Ex Choisy) leaves were characterized by the identification of 22 and 33 compounds represented (95.88 and 91.82 %), respectively. It composed mainly of hydrocarbons and oxygenated compounds. The GC/MS of fatty acids methyl ester (FAME) led to the identification of 8 and 10 compounds for I. tricolor and I. fistulosa, respectively. Linolenic and palmatic acids were found as the predominant fatty acids. On the other hand, the petroleum erher extract of I. tricolor was fractionated on column chromatography to yield major compounds; 5-phenyldecane and 4-phenyldecane, as well as, triterpenes including β-amyrin, lupeol and simiarenol, in addition to α- amyrin, β-sitosterol, stigmasterol and α- amyrin acetate which isolated for the first time from this species. The petroleum ether extracts of I. tricolor and I. fistulosa showed a significant increase in DPPH inhibition activity at 0.01 and 0.05 ug/ml, respectively. Furthermore, I. tricolor extract exhibited a significant increase in cholinesterase inhibition activity at concentration 20 ug/ml and a significant anti-inflammatory activity with IC50 117.4µg/ml.

Energy management and control of hybrid microgrids is a challenging task due to the varying nature of operation between AC and DC components which leads to voltage and frequency issues. This work utilizes a metaheuristic-based vector-decoupled algorithm to balance the control and operation of hybrid microgrids in the presence of stochastic renewable energy sources and electric vehicles charging structure. The AC and DC parts of the microgrid are coupled via a bidirectional interlinking converter, with the AC side connected to a synchronous generator and portable AC loads, while the DC side is connected to a photovoltaic system and an electric vehicle charging system. To properly ensure safe and efficient exchange of power within allowable voltage and frequency levels, the vector-decoupled control parameters of the bidirectional converter are tuned via hybridization of particle swarm optimization and artificial physics optimization. The proposed control algorithm ensures the stability of both voltage and frequency levels during the severe condition of islanding operation and high pulsed demands conditions as well as the variability of renewable source production. The proposed methodology is verified in a state-of-the-art hardware-in-the-loop testbed. The results show robustness and effectiveness of the proposed algorithm in managing the real and reactive power exchange between the AC and DC parts of the microgrid within safe and acceptable voltage and frequency levels.

Managing electric vehicles charging activities during times when the electrical grid is congested is a challenging task. In this work, we propose a fair, real-time, demand-influenced dynamic pricing structure to accurately allocate more fairness to the billing strategy to reflect updated energy prices during real-time operation of the microgrids. This pricing structure is composed of two pricing fractions; retail energy price that follows time-of-use (ToU) rates, and congested energy price that is allocated solely for billing EVs charging events during congested timeslots. The proposed methodology is implemented in a hierarchal multi-agent architecture with a stochastic energy management system that aims to provide a cost-efficient microgrid operation. The inputs to the optimization problem are day-ahead PV forecast as well as stochastic EVs energy levels and connectivity times prediction models based on a discrete-time Markov chain. Moreover, a predictive model of daily load demand is also presented based on adaptive Artificial Neural Network (ANN). We develop these models based on historical data for Miami Dade County, South Florida. Through numerical simulations, we attest that the proposed pricing structure achieves significant energy prices reduction when compared with results from previous well-established pricing policies.

Summary Ocean Bottom Node (OBN) surveys provide full azimuth coverage with long offsets and rich bandwidth. These attributes improve the resolution, stability, and steep-dip fidelity of seismic images derived from the data, which are desirable for 4D monitoring of a producing oilfield. However, acquisition of OBN data is expensive, and it is important to understand the impact of receiver density (which directly affects the acquisition cost) on the resultant seismic image. Here, using a dense North Sea 4D dataset, we demonstrate the impact of node density on both the 3D and 4D seismic image by migrating progressively sparser node configurations (including 50x300 m and 300x300 m cases) and comparing the results. It is shown that 4D image quality is more sensitive to changes in node density than is the 3D image. Furthermore, an acceptable sparse survey for 3D imaging may be inadequate for 4D applications. Attempts to mitigate the effects of reduced node density with processing methods show partial success for 4D imaging, but serve to highlight the importance of suitable node density in 4D survey design for North Sea OBN data. Our tests suggest a minimum node density of 100x300 m is necessary for this 4D example.

Objectives Data about the circulating levels of cyclophilin A and matrix metalloproteinase-9 in stable coronary artery disease are contradictory. Moreover, their relationship in this disease is not established yet. Thus, this study was designed to assess the relationship between the circulating levels of cyclophilin A and matrix metalloproteinase-9 in coronary artery disease patients with and without type 2 diabetes mellitus (T2DM). Methods Serum levels of cyclophilin A, matrix metalloproteinase-9, and high sensitive C-reactive protein (hsCRP) along with fasting blood glucose, glycated hemoglobin, serum lipids, and the anthropometric parameters were measured in 120 participants who were divided equally into four groups (i) normal controls, (ii) T2DM patients, (iii) stable coronary artery disease patients with T2DM, and (iv) stable coronary artery disease patients without T2DM. Results Levels of cyclophilin A and matrix metalloproteinase-9 were significantly elevated in sera of coronary artery disease patients with and without T2DM compared to normal controls and T2DM patients. In multiple linear regression models, only cyclophilin A was observed in the final model where it explained the 24.9% variability of matrix metalloproteinase-9. Additionally, high circulating levels of cyclophilin A and matrix metalloproteinase-9 were associated with an increased risk of developing stable coronary artery disease. Finally, the diagnostic efficacy of cyclophilin A and matrix metalloproteinase-9 to discriminate stable coronary artery disease patients with and without T2DM from subjects without coronary artery disease was found to be higher than that of hsCRP. Conclusion Serum level of cyclophilin A might be a determinant factor of matrix metalloproteinase-9 level; both may contribute to the pathogenesis of stable coronary artery disease and they appear to be valuable diagnostic biomarkers of stable coronary artery disease with and without T2DM.

The optimal reactive power dispatch (ORPD) problem represents a noncontinuous, nonlinear, highly constrained optimization problem that has recently attracted wide research investigation. This paper presents a new hybridization technique for solving the ORPD problem based on the integration of particle swarm optimization (PSO) with artificial physics optimization (APO). This hybridized algorithm is tested and verified on the IEEE 30, IEEE 57, and IEEE 118 bus test systems to solve both single and multiobjective ORPD problems, considering three main aspects. These aspects include active power loss minimization, voltage deviation minimization, and voltage stability improvement. The results prove that the algorithm is effective and displays great consistency and robustness in solving both the single and multiobjective functions while improving the convergence performance of the PSO. It also shows superiority when compared with results obtained from previously reported literature for solving the ORPD problem.

The fast development of the residential sector regarding the additional integration of renewable distributed energy sources and the modern expansion usage of essential DC electrical equipment may cause severe power quality problems. For example, the integration of rooftop photovoltaic (PV) may cause unbalance, and voltage fluctuation, which can add constraints for further PV integrations to the network, and the deployment of DC native loads with their nonlinear behavior adds harmonics to the network. This paper demonstrates the smart integration of a DC microgrid to the neighborhood low-voltage distribution network (NLVDN). The DC microgrid is connected to the NLVDN through a three-phase voltage source inverter (VSI), in which the VSI works as a distribution static compensator (DSTATCOM). Unlike previous STATCOM work in the literature, the proposed controller of the VSI of the DC smart building allows for many functions: (a) it enables bidirectional active/reactive power flow between the DC building and the AC grid at point of common coupling (PCC), (b) it compensates for the legacy unbalance in the distribution network, providing harmonics elimination and power factor correction capability at PCC, and (c) it provides voltage support at PCC. The proposed controller was validated by Matlab/Simulink and by experimental implementation at the lab.

A real-time, data-driven electric vehicle (EVs) routing optimization to achieve energy consumption minimization is proposed in this work. The proposed framework utilizes the concept of Double Deep Q-learning Network (DDQN) in learning the maximum travel policy of the EV as an agent. The policy model is trained to estimate the agent's optimal action per the obtained reward signals and Q-values, representing the feasible routing options. The agent's energy requirement on the road is assessed following Markov Chain Model (MCM), with Markov's unit step represented as the average energy consumption that takes into consideration the different driving patterns, agent's surrounding environment, road conditions, and applicable restrictions. The framework offers a better exploration strategy, continuous learning ability, and the adoption of individual routing preferences. A real-time simulation in the python environment that considered real-life driving data from Google's API platform is performed. Results obtained for two geographically different drives show that the proposed energy consumption minimization framework reduced the energy utilization of the EVs to reach its intended destination by 5.89% and 11.82%, compared with Google's proposed routes originally. Both drives started at 4.30 PM on April 25th, 2019, in Los Angeles, California, and Miami, Florida, to reach EV's charging stations that are located six miles away from both of the starting locations.

in this paper, a hybrid residential microgrid system was considered for future city houses. It is composed of both AC and DC networks tied together through an interlinking bidirectional AC/DC converter (IC). The DC network contains the DC loads and the distributed energy sources (DES) such as Photovoltaic (PV) and battery storage. The AC network includes the AC loads and a synchronous AC generator as the only AC source in islanding operation in this system. The islanding operation at this level of the grid, prone the network to be more vulnerable to stability issues. Therefore, it is essential to obtain the best control parameters for the IC controller, which ensure sufficient power exchange and stable operation between the DC/AC networks. Consequently, a Genetic Algorithm (GA) has been used to tune the vector decoupling control parameters of the IC controller to find the best parameters combination to improve the hybrid grid performance. The proposed scheme maintains the system stability during various condition such as variable or pulsed demand and uncertain renewable power sharing. The tuned vector decoupling controlled sinusoidal pulse width modulation (SPWM) technique has been used to not only allow the IC to maintain stable voltage and frequency but also tracks the active and reactive power set points.

The new vision for moving the power system to a smart grid enables a variety of smart applications at different power system infrastructure's levels. Households represent a massive section of the grid infrastructure which could not be considered as a smart grid without smart households integrated into it. Short Term Load Forecasting (STLF) is the essential tool needed in the management and control techniques required for households to be smart. STLF at this level of the grid is very challenging due to the high percentage of uncertainty in the load demand, influenced by customer behavior, which is too stochastic to predict. In this paper, a new approach for STLF of household load demand is employed based on artificial neural network (ANN) and a pre-processing stage of a Non-Intrusive Load Monitoring (NILM) techniques. The NILM techniques extract the individual load pattern from the available historical aggregated load demand. These new features increase the training data window for the ANN forecaster and achieve a significant enhancement for its prediction performance. By comparing the new approach with the state of the art techniques in household load forecasting, the proposed method outperforms feed-forward artificial neural network (FFANN) regarding RMSE. Two techniques of NILM were used to emphasize the correlation between the NILM disaggregation accuracy performance and the load forecasting enhancement performance.

Reflection full waveform inversion is a formulation of full waveform inversion designed to extract low wavenumber velocity information from the reflected wavefield. In this works we extend reflection full waveform inversion to an elastic framework. This allows the estimation of both P-wave and S-wave velocities using reflected waveforms. We apply the method to a 3D-3C field dataset. The results clearly show that the velocities estimated with the method improve the quality of the PS image. The method is also able to incorporate in the velocity model information about the location of channel deposits at a depth of about 1200 meters.

In this paper, an accelerated two-qubit system initially prepared in maximum or partial entangled state, which interacts locally with white/color or white-color noises, is considered. Due to the acceleration process and the noise effect, the entanglement degraded. Therefore, the effect of noise strength, initial state settings and the acceleration on the survival entanglement are investigated by means of the concurrence. Moreover, the initial parameters that describe this system are estimated by using the quantum Fisher information, where two forms are considered, namely by using a single and two-qubit forms. It is shown that, by using the two-qubit form, the estimation degree of these parameters is larger than that displayed by using a single-qubit form.

The real-time operation of the energy management system (RT-EMS) is one of the vital functions of Microgrids (MG). In this context, the reliability and smooth operation should be maintained in real time regardless of load and generation variations and without losing the optimum operation cost. This paper presents a design and implementation of a RT-EMS based on Multiagent system (MAS) and the fast converging T-Cell algorithm to minimize the MG operational cost and maximize the real-time response in grid-connected MG. The RT-EMS has the main function to ensure the energy dispatch between the distributed generation (DG) units that consist in this work on a wind generator, solar energy, energy storage units, controllable loads and the main grid. A modular multi-agent platform is proposed to implement the RT-EMS. The MAS has features such as peer-to-peer communication capability, a fault-tolerance structure, and high flexibility, which make it convenient for MG context. Each component of the MG has its own managing agent. While, the MG optimizer (MGO) is the agent responsible for running the optimization and ensuring the seamless operation of the MG in real time, the MG supervisor (MGS) is the agent that intercepts sudden high load variations and computes the new optimum operating point. In addition, the proposed RT-EMS develops an integration of the MAS platform with the Data Distribution Service (DDS) as a middleware to communicate with the physical units. In this work, the proposed algorithm minimizes the cost function of the MG as well as maximizes the use of renewable energy generation; Then, it assigns the power reference to each DG of the MG. The total time delay of the optimization and the communication between the EMS components were reduced. To verify the performance of our proposed system, an experimental validation in a MG testbed were conducted. Results show the reliability and the effectiveness of the proposed multiagent based RT-EMS. Various scenarios were tested such as normal operation as well as sudden load variation. The optimum values were obtained faster in terms of computation time as compared to existing techniques. The latency from the proposed system was 43% faster than other heuristic or deterministic methods in the literature. This significant improvement makes this proposed system more competitive for RT applications.

Demand side management has a vital role in supporting the demand response in smart grid infrastructure, in the decision-making of energy management, in household applications is significantly affected by the load-forecasting accuracy. This paper introduces an innovative methodology to enhance household demand forecasting based on energy disaggregation for Short Term Load Forecasting. This approach is constructed from Feed-Forward Artificial Neural Network forecaster and a pre-processing stage of energy disaggregation. This disaggregation technique extracts the individual appliances’ load demand profile from the aggregated household load demand to increase the training data window for the proposed forecaster. These proposed algorithms include two benchmark disaggregation algorithms, Factorial Hidden Markov Model (FHMM), Combinatorial Optimization in addition to three adopted Deep Neural Network, long short- term memory (LSTM), Denoising Autoencoder, and a network which regress start time, end time, and average power. The proposed load forecasting approach outperformed the currently available state-of-the-art techniques, namely root mean square error (RMSE), normalized root mean square error (NRMSE), and mean absolute error (MAE).

This paper introduces the design and implementation of a programmable AC/DC active load emulator that has the capability to emulate a very wide range of active power with the ability to change the power with small steps to give flexible load emulation. The developed load emulator can mimic the real time active power characteristic of a daily load pattern which can be used in testing power management algorithms. It gives an easy tool to test the performance of the utility grid by emulating different load profiles like random residential loads and electric vehicle charging stations. Furthermore, it can be used in the shipboard power system to emulate pulsated load. A friendly user GUI is developed in LabVIEW to facilitate the control of the load emulator. Actual hardware implementation steps are explained in details. The initial experimental results show the validity of the developed active power emulator and its capability to mimic different load profiles.

Installation of a Photovoltaic (PV) system needs an accurate design and evaluation test for the performance of its modules before using them in a system. This can be fulfilled with high accuracy in the laboratory without using commercial PV modules by using a PV emulator. The PV emulator introduces a suitable tool which easily permits emulating PV system component with different parameters, teaching its characteristic and training researchers in this field. The main purpose of this paper is introducing the development of a Photovoltaics (PV) emulator has the capability of emulate commercial PV modules with different parameters and under different environmental condition (irradiance or temperature change), constructing a PV array based on the series and parallel numbers of modules. The PV emulator was implemented using a real-time algorithm representing the PV array mathematical model and generating the reference output power from a programmable DC power supply. The PV model is simulated in MATLAB and interfaced to the real world through dSPACE using an evolutionary graphic user interface (GUI). This laboratory PV emulator is tested with real-time execution of PV model for the steady state and dynamic operating conditions.

We describe briefly the properties of the recently completed Southern African Large Telescope (SALT), along with its first light imager SALTICAM. Using this instrument, we present 4.3 hr of high speed unfiltered photometric observations of the eclipsing polar SDSSJ015543.40+002807.2 with time resolution as short as 112 ms, the highest quality observations of this kind of any polar to date. The system was observed during its high luminosity state. Two accreting poles are clearly seen in the eclipse light curve. The binary system parameters have been constrained: the white dwarf mass is at the low end of the range expected for cataclysmic variables. Correlations between the positions of the accretion regions on or near the surface of the white dwarf and the binary system parameters were established. The sizes of the accretion regions and their relative movement from eclipse to eclipse were estimated: they are typically 4-7 deg depending on the mass of the white dwarf. The potential of these observations will only fully be realised when low state data of the same kind are obtained and the contact phases of the eclipse of the white dwarf are measured.

The main purpose of this paper is to propose a fault detection and fault tolerant control mechanism to maintain the continuous operation of the grid tied inverter, which is commonly used to interface renewable energy and distributed generation to the grid. The fault tolerance is provided using modified topology of the DC-AC power converter with redundant standby branch. The proposed system insures the continuous operation without isolating the energy source from the grid during faults on inverter switch. The fault may be open circuit fault or short circuit fault.

Objective: To present a case of culture-proven typhoid fever in which granulomas were demonstrated histologically in the ileum and mesenteric lymph nodes. Clinical Presentation and Intervention: A 47-year-old Pakistani man underwent emergency hemicolectomy for severe bleeding per rectum associated with diarrhea. Two large ulcers in the ileum, near the ileocolic junction, as well as mesenteric lymph nodes showed both necrotizing and non-necrotizing granulomas in addition to mixed inflammatory infiltrate on histology. Conclusion: Typhoid fever may be considered as one of the causes of the differential diagnoses of granulomatous inflammation of the small intestine.

Spring barley cultivars and lines were tested for 3 years in field studies for adult plant resistance against Erysiphe graminis f.sp. hordei. The cultivars Osiris and Asse were selected for further detailed cytological studies and compared with the susceptible cultivar Peruvian. Under controlled greenhouse conditions, the percentage of conidia that had formed a functional haustorium and secondary hyphae (infection efficiency) was reduced in fifth leaves of the adult plant resistant cultivars. On fifth and flag leaves of adult plant resistant cultivars, papillae were formed more frequently under primary germ tubes and appressoria, and fungal penetration was prevented more often than on the susceptible cultivar Peruvian. In ultrastructural studies various types of papillae were observed, but could not be strictly correlated with penetration success or failure of the fungus.

Light and electron microscopical studies on the effect of a culture filtrate of Erwina herbicola B 247 and herbicolin A on Fusarium culmorum The effect of a culture filtrate of Erwinia herbicola B 247 and the antibiotic herbicolin A, respectively, on the hyphae of Fusarium culmorum was studied in vitro using light and electron microscopy. The light microscopy revealed a swelling and disruption of the hyphae tips with a release of cytoplasm. Ultrastructural investigations demonstrated the appearance of electron-dense material of a round or tubular structure in the cell wall. On its inner side, an accumulation of electron-dense material formed a spongy structure associated with the altered plasma membrane. Finally, a complete dissolution of the cell wall was observed. Zusammenfassung Die Wechselwirkung in vitro zwischen fusarium culmorum und einem Kulturfiltrat von Erwinia herbicola B 247 bzw. dem Antibiotikum Herbicolin A wurde licht- und elektronerumikroskopisch untersucht. Lichtmikroskopisch lies sich ein Auftreiben und Platzen der Hyphen von F. culmorum an ihren Spitzen mit einem Austritt von Cytoplasma erkennen. Elektronenmikroskopische Untersuchungen zeigten ein Auftreten elektronendichter, rundlicher oder tubularer Strukturen in der Zellwand sowie von innen angelagerte Verdickungen, die mit der Zellmembran verbunden zu sein schienen. Die Plasmamembranauslaufer und Zellwandanlagerungen bildeten eine schwammartige Schicht. Schlieslich war eine vollstandige Auflosung der Zellwand zu beobachten.

Polyclonal antiserum prepared against barley cell wall thionin was used to localize and quantitate immunoreactive material on the cellular level in healthy and rust-infected leaves of barley and wheat. Three types of sites were used for the immunocytochemical analysis: as control sites, mesophyll cell walls were selected in uninoculated leaves, and in leaves that were inoculated with rust but where the sites were not in contact with the pathogen: these were compared with mesophyll cell walls that were in contact with intercellular rust hyphae in inoculated leaves. Similar amounts of cell wall thionin were detected in all 3 barley cultivars before inoculation. At sites where intercellular hyphae of Puccinia hordei had made contact with mesophyll cell walls, less thionin was found in the compatible host cv. Larker, but in incompatible hosts (cvs. Gold and Bolivia) the thionin concentration did not differ from that of the controls. Two cultivars of wheat were studied with respect to immunoreactive material in their mesophyll cell walls, the universal rust suscept cv. Little Club and the highly rust-resistant cv. Khapli. Before inoculation, leaves of cv. Khapli contained about twice the amount of immunoreactive material in mesophyll cell walls than those of cv. Little Club. This relation was unchanged in walls that had made contact with P. graminis tritici, but in non-contacted walls of infected cv. Little Club leavest, he concentration of this material had risen to levels typical for those of cv. Khapli. Tests for immunoreactive material with pre-embedding cytochemistry yielded negative results, indicating that it is not exposed on the surface of mesophyll walls in barley and wheat.

Determination and evaluation of quantitative virus resistance in poplars inoculated with poplar mosaic virus (PopMV). Statistical analysis of data on symptom severity and virus concentration in PopMV-infected leaves were used to determine differences in virus resistance among poplar clones. These differences were confirmed in ultrastructural studies.

The progress of infection by high- and low-virulence isolates of Mycosphaerella pinodes was examined in susceptible and partially resistant pea leaves. Conidia germinated with one or more germ tubes which frequently branched and formed appressorium-like structures on the leaf surface. Penetration occurred through the epidermal walls. A structure similar to an infection vesicle was formed, lying partly in the epidermal wail and partly in the cell lumen. From this structure, a penetration hypha was derived which initiated the development of the intra- and intercellularly-growing fungal colony. Infections led to rapid tissue collapse in both susceptible and resistant interactions. In resistant interactions, the formation of infection vesicles and penetration hyphae was reduced, and the development and spread of lesions was retarded.

Two types of spherical viruslike particles measuring ca. 25–30 nm and 80 nm in diameter, respec-tively, were found both in ringfleck mosaic affected mountain ash and adjacent raspberry bushes in the Bavarian Forest. The smaller particles were also found in symptomless mountain ash in the same forest. The sap from infected mountain ash reacted with an antiserum to tomato spotted wilt virus in agar-gel-diffusion test. No reactions were obtained with raspberry or mountain ash sap when tested against antisera to a number of small spherical plant viruses.

Barley yellow striate mosaic virus (BYSMV) was identified in Iran by electron microscopy and serology. The virus was widespread in the Fars province causing mosaic, stunting and head sterility in wheat and mosaic symptoms in Setaria spp. In 1989, about 1/3 of wheat plants in the Bajgah Experiment Station, 15 km north of Shiraz, were infected. The yield in individual plants was drastically affected. Rhabdovirus particles were consistently observed in leaf-dip preparations and thin sections from the infected plants. The virus was transmitted by Laodelphax stritellus to wheat. It reacted with BYSMV antisera from Italy and Morocco but not with antisera to several other rhabdoviruses of gramineous plants.

Distribution of Xanthomonas populi subs, populi was studied 21 days postinoculation in highly susceptible, susceptible and tolerant poplar clones (Populus trichocarpa): Heimburger, Muhle-Larsen and Columbia River. Bacteria were observed in the intercellular spaces of leaf trace of both clones Heimburger and Muhle-Larsen. No bacteria were detected 21 days after inoculation (dpi) in ultrathin sections of the clone Columbia River. The direct effect of bacteria on the host cells was the expanding intercellular space of leaf traces by dissolution of the middle lamellae and cell walls, and collapse of the surrounding cells. Sixteen weeks following the inoculation a tumour developed only at the inoculation site of the clone Muhle-Larsen; Heimburger showed longitudinal cracks.

Death is an inevitable phenomenon which strikes at any time during a person's infancy, youth or old age. But, one cannot overlook the fact that before the inevitable (i.e. death) does take place a person may become a victim of a terminal illness, or may lapse into irreversible coma, or persistent vegetative state (PVS). In various countries, an increasing number of healthy people have appended their signatures on what is called the Living Will (Advanced Medical Directive), which is in effect a document safeguarding their right to die. This paper discusses the clauses embodied in the Living Will from an Islamic ethico-legal perspective with the aim of ascertaining its validity.

Death is an inevitable reality but the causes leading to death may vary from individual to individual. In the past, death was considered to be a simple and straightforward phenomenon. The general practitioner would issue the death certificate once he was convinced that there was cessation or absence of spontaneous life in the patient. This meant that the patient had stopped breathing, his heart had stopped beating, there was unresponsiveness, his body had turned cold and finally rigor mortis had set in. With the successful accomplishment of heart transplants, it became obvious that a process of rethinking on how death could be determined had to be instituted. Cessation of heartbeat is no longer considered evidence of death since the heart is now able to be substituted with that of a just-deceased donor or with that of a baboon or even with a mechanical one. Moreover, modern biomedical innovations like the resuscitator and cardiac pacemaker have made it imperative to establish a set of criteria by which the moment of death could be identified. Diagnosis of brainstem death is relevant to the issue of retrieving viable vital organs, i.e. heart, lung, liver and kidney, for transplantation purposes. The Holy Qur'an emphasizes the universality of death and from its teachings one gathers that the moment of death would be at the time when the soul is separated from the body. However, one has to concede that the Qur'an does not in any way tell us anything about the nature of the soul nor of its location in the human body, hence the dilemma of Muslims insofar as brain death is concerned. In this paper, an attempt is made to analyse the deliberations of the classical and contemporary Muslim scholars on the end of human life with the aim of determining whether brain stem death could in effect be regarded by Muslims as the end of human life and if not why?

Rickettsia-like organisms (RLO) in fine roots of different age diseased spruce. Rickettsia-like organisms (RLO) were observed in fine roots of Norway spruce (Picea abies Karst.) with symptoms of forest decline at two sites in the Federal Republic of Germany. Conclusions about the causal relations of RLO to the observed symptoms are however not yet possible.

Fifth leaves of the barley cultivar ‘Osiris’ with adult plant resistance against powdery mildew were inoculated with Erysiphe graminis f. sp. hordei. Samples were taken at 32 hours after inoculation for cytochemical treatments and electron microscopy. Deposition of gold-labelled wheat germ lectin was detected in the wall of the haustorial neck of the fungus and in an outer layer of a papilla, indicating the presence of oligomers of N-acetylglucosamine. Con A binding was detected mainly, in a middle layer of a papilla, demonstrating the presence of α-bound glucose and/or mannose. Treatment with PA-TSH-SP revealed glycosubstances with vicinal hydroxyl groups present mainly in an outer layer of another type of papilla. Pretreatment with, protease before PA-TSH-SP staining resulted in a positive Thiery reaction in spherical structures of a papilla, indicating that vicinal hydroxyl groups were exposed to staining after removal of protein from these structures. Zusammenfassung Ultrastrukturelle und histochemische Untersuchungen zum Mehltau auf Gerste (Erysipbe graminis DC f. sp. hordei Marchal) IV. Charakterisierung der Papillen in den funften Blattern mit Altersresistenz Funfte Blatter der Gerstensorte, Osiris’ mit Altersresistenz gegen Mehltau wurden mit Erysiphe graminis f. sp. hordei inokuliert. Proben fur cytochemische Behandlungen und Elektronenmikroskopie wurden 32 Stunden nach Inokulation genommen. Deposition von gold-markiertem Weizenkeimlektin als Hinweis fur die Anwesenheit von N-Acetylglukosamin-Oligomeren wurde in der Wand des Haustorienhalses und in einer auseren Schicht der Papille gefunden. Bindung von goldmarkiertem Con A als Anzeichen fur die Anwesenheit von α-Glukose und/oder Mannose wurde hauptsachlich in einer mittleren Schicht der Papille nachgewiesen. Behandlung mit PA-TSH-SP ergab den Hinweis, das Glykosubstanzen mit vicinalen Hydroxylgruppen hauptsachlich in der auseren Schicht eines anderen Typs von Papillen vorkommen. Vorbehandlung mit Protease vor der PA-TSH-SP Anfarbung fuhrte in spherischen Strukturen einer Papille zu einer positiven Thiery-Reaktion, die offenbar auf der Freilegung von vicinalen Hydroxylgruppen durch die Ablosung von Protein von diesen Strukturen beruht.