Viral Vectors

Objective
Maize (Zea mays L.) is a key cereal crop throughout the world and important model for plant genetics and biology. Establishment of an efficient transient gene expression system in maize facilitates plant functional genomics projects using gene silencing or heterologous protein overexpression strategies. The present study was aimed at optimizing an Agroinjection-mediated SCMV-based systemic heterologous gene expression system in maize.
Materials and methods
Recombinant DNA encoding sugarcane mosaic virus (SCMV) containing the coding sequence of green fluorescent protein between the protein 1 (P1) and helper component‐proteinase (HC‐Pro) cistrons, in‐frame with the viral open reading frame, was introduced into the meristematic tissue, above the coleoptilar node, of maize seedlings via a direct Agroinoculation procedure. The efficiency of Agrobacterium tumefaciens strains EHA105 and GV3101 in delivering the recombinant vector into three and seven-day old seedlings of three maize varieties, including sweet corn (Iochief and Golden Bantam varieties) and dent corn (inbred line B73), was examined. Expression of GFP transgene in symptomatic Agroinoculated plants was assessed by confocal fluorescent microscopy and RT-PCR in comparison with controls.
Results
Results of RT-PCR and confocal fluorescent microscopy revealed that: 1) A. tumefaciens GV3101 is significantly more successful in delivering the recombinant SCMV-based vector into maize plants than EHA105, 2) the percentage of GFP-expressing Golden Bantam plants is significantly higher than two other maize varieties, and 3) The effectiveness of growth stage of maize seedlings on the percentage of GFP expressing Agroinjected plants depends upon the interactions between Agrobacterium strain and maize genotype.
Conclusions
In conclusion, a combination of the Golden Bantam maize variety and A. tumefaciens strain GV3101 for direct Agroinjection of the SCMV-based vector into seedlings at the early two-leaf stage could be a fast and efficient system for investigating gene functions in maize.

Respiratory syncytial virus rapid antigen detection tests (RADT) are used widely. RADT exhibited high specificity (97%) and moderate sensitivity (80%) compared with reverse-transcriptase polymerase chain reaction in 720 hospitalized children <3 years old. Older age, prolonged symptoms, and respiratory syncytial virus genotype-B infection were significantly associated with false-negative results of RADT.

Treating monogenic disorders via gene therapy although still considered experimental by some, has becoming a more accepted method lately especially in these last 10 years with a number of recent clinical successes. Genetic modifications are becoming easier to perform with the progressing technology and discovery of new techniques such as the Clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR associated protein 9 (Cas9) methods which can modify DNA with great ease and accuracy. Gene therapy is a powerful technique with huge potential to treat psychiatric and neurodegenerative disorders including Alzheimer’s and Parkinson’s disease. Gene therapy is simple in principle, which is corrective genetic material is sent into cells and the disease is cured by ending the problem at its source. Viral and non-viral vectors which are used for the delivery of the desired genes to the targeted cells are briefly listed and explained. Unlike viral vectors non-viral vectors don’t cause an immune response but their pretty low transfer rate makes them rather less interesting for research. Viral vectors of adenoviruses, adeno-associated viruses, retroviruses with its subclass of lentiviruses and herpes viruses are compared with their advantages and disadvantages related to usage in brain and CNS treatment of our topic. Neurotrophic factors (NTFs) have important roles in brain and nervous tissue. Delivering NTFs via viral vectors for treating neurodegenerative diseases is a promising approach. Providing information about principles, methods, hurdles and clinical applications of gene therapy with its historic background to present it with its all basic details and therapeutic effects it can provide to problems related to brain are aimed in this writing.

Gene transfer into haematopoietic stem cells (HSCs) has now come to the stage where it can be recognized as a form of established therapy for patients with a certain range of genetic diseases. Primary immunodeficiency disease (PID) represents an ideal pathological target for this type of genetic medicine, that is HSC gene therapy, as exemplified well by the successful cases with adenosine-deami-nase (ADA) deficiency. Other diseases including X-linked severe combined immu-nodeficiency disease (X-SCID), chronic granulomatous disease (CGD) and Wiskott–Aldrich syndrome (WAS) have also been the targets of gene therapy, but the efficacy reportedly varies considerably. In addition, all those diseases except ADA deficiency have been demonstrated to be subject to an inherent risk of insertional leukaemogenesis as long as gene transfer accompanies genomic insertion. Researchers therefore should continue to aim for further improvement of HSC gene therapy to maximize both safety and efficacy. To achieve this aim, an ideal model system is desired, by which faithful recapitulation of the disease-related pathophysiology is feasible. Recently, a new model system possibly constituting such an ideal platform has come to reality; that is, patient-/disease-specific induced pluripotent stem cells (iPSCs). iPSCs should particularly be useful for modelling genetic disorders, because of their excellent potential to differentiate into any types of somatic cells while retaining the patient-specific genetic mutations. These model cells should allow testing various kinds of genetic manipulation and also detailed analysis of the target cells before/after differentiation , thus providing a disease-specific platform for preclinical studies to test safety and efficacy of each gene-modification procedure.

Presentation stating why the adeno-associated viruses prove to be an ideal vectors as a result of their abilities as
non-pathogenic,
non-oncogenic, and
ignorance of immune excitation.
The primary attribute that makes adeno-associated viral vectors ideal is their ability to infect non-diving cells, instigating repeatable chromosomal changes leading to long-term expression, an attribute which may not be necessary in the hippocampus, but is most definitively necessary for a majority of neurons as a result of their terminal differentiated nature.

An overview of how viruses-retroviruses could be utilized as to instigate viral bio-weaponization and bio-warfare (much like other pathogens as bacteria, fungi, etc.), as well as a highlight of the history of how this has occurred in the past, has been presented. In particular, two issues need to be clarified here. First of all, almost all of our history of evolution prior to 5,500 years ago has been purged from the records, as well any memory of such happenings have been blank-slated from our consciousness memories. Secondly, that humanity has been lurking in the low dimensional level of consciousness, without having a clue about some of the advanced technologies with regard to the true nature of its genetics, and the possibility of its manipulation leading to genetic mutations and alien hybridization. However, as of more recently, with the advent of knowledge of radiation technological development, together with more novel approaches as nanotechnology in materials science, as well as the fact that we are beginning to better understand the nature of our bioenergetics and the role it plays in our genetics and physiognomy and holographic reality, we are beginning to get a better grasp of how a formidable nefarious alien artificial intelligence machinery can play a devastating role in our genetic modification, hybridization, as well as the using viral bio-weaponization for our demise or total annihilation. Thus, in the present paper, the author

ABSTRACT
Background: For the past two decades, Acinetobacter spp. have emerged as an important
pathogen globally in various infections. Objectives: This study was conducted to determine the
frequency, risk factors, and antibiotic resistance pattern of Acinetobacter spp. from various clinical
samples. Materials and Methods: This retrospective, hospital record–based, cross‑sectional study
included a total of 8749 clinical samples collected from patients at a tertiary care hospital in Odisha,
India from July 2010 to December 2012. The samples were processed and identified by standard
protocol. The Acinetobacter isolates were tested for antibiotic resistance by Kirby‑Bauer disk
diffusion method [according to the Clinical and Laboratory Standards Institute (CLSI) guidelines].
Results: From 8749 clinical samples, 4589 (52.5%) yielded significant growth and only 137 (3%,
137/4589) Acinetobacter spp. were isolated. Maximum (56.9%) isolates were obtained from pus/
swab, followed by blood (13.1%) and urine (12.4%). Elderly age, being inpatients, longer duration of
stay in the hospital, associated co‑morbidity, and invasive procedure were found to be significant risk
factors in the setup investigated (P is less than 0.05). Out of 137 isolates, 75 (54.7%) were resistant
to more than three classes of antibiotics (multidrug resistant) and 8 (5.8%) were resistant to all
commonly used antibiotics (pan‑drug resistant). Majority of the isolates were sensitive to imipenem,
meropenem, and piperacillin/tazobactam, and showed resistance rates of 19%, 22%, and 23%,
respectively. All eight pan‑drug resistant isolates were 100% sensitive to colistin. Conclusion: This
hospital‑based epidemiological data will help to implement better infection control strategies and
improve the knowledge of antibiotic resistance patterns in our region.
Key words: Acinetobacter species, antibiotics, frequency, resistance, risk factors

The story of medical bacteriology and its attempt to »eradicate« all of mankind`s »invisible enemies«: the rise and fall of a leading science in the modern age.

When the WHO announced the »eradication of smallpox« in 1980, the vision of a world free of infectious diseases seemed to be within reach. For the first time, it seemed possible to »wipe out« epidemics by means of bacteriology. However, just a short time later, when new pathogens emerged and old ones resurfaced that had long since been considered defeated, it became clear that this was an illusion. Focussing on Germany between 1890 and 1933, Silvia Berger reveals that this was not the first time that the belief in the possibility of controlling infectious diseases had been shattered. After the First World War, bacteriology was already facing a serious crisis. The dream of destroying all »invisible enemies« and creating »pure« bodies and territories, rigorously pursued by military bacteriologists between 1914 and 1918, now faded into the background. In the 1920s, the scientists working in this exclusive field were forced to admit that they were no longer in a position to explain the complex interaction of micro and macro-organisms with their hypotheses. Rather than being considered a »war«, the relationship between bacteria and humans began to be expressed in terms such as »balance« or »symbiosis«, as a kind of peaceful co-existence.

In 2008, the study was awarded the Henry-E.-Sigerist Prize for young academics by the Swiss Society for the History of Medicine and Science. 2009 the book won the Förderpreis of the German Society for the History of Medicine, Natural Science and Technology.

»a highly original work, constituting an outstanding contribution to the history of preventive medicine and to German history«
Paul Weindling, Oxford

"Ohne Übertreibung darf man festhalten, dass mit Silvia Bergers Buch die Wissenschaftsgeschichte der Bakteriologie in der Zwischenkriegszeit im Wesentlichen geschrieben ist und es ganz erheblicher Anstrengungen bedürfte, an dieser Deutung vor- bei zu kommen."
Christoph Gradmann, Oslo

" [...] a highly valuable and original work. It fully deserves an English translation in order to reach a larger readership."
Jean-Paul Gaudillière, Paris

This paper demonstrates the Direct Torque Control Permanent Magnet Synchronous Motor (DTC-PMSM) drive fed by asymmetrical multilevel inverter. The cascaded H-bridges topology with ratio-3 dc voltage sourced cells inverter has been employed. The DTC controller receives a reference torque and flux signals, the torque controller output determines the position of the desired flux vector. The amplitude of this vector is determined by the reference flux amplitude. The reference voltage vector is calculated as a continuous value using a technique developed originally for the SVM controlled drive. In this study, however, the reference voltage vector has been approximated to the nearest voltage vector achievable by one switching state of the multilevel inverter. The performance of two- and three-cells per arm inverter drives has been compared to that of the SVM-inverter drive at two values of the switching intervals. The results reflect the low switching frequency and torque ripple advantages of the proposed scheme. © 2008 IEEE.

http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=4692567&reason=concurrency

Both helper dependent expression systems, based on two components, and single genomes constructed by targeted recombination, or by using infectious cDNA clones, have been developed. The sequences that regulate transcription have been characterized mainly ...

SARS-CoV-2 is a genetically engineered SARS-COV vector which has been embedded into the backbone of bacteriophage HP2 of Nontypeable Haemophilus Influenza (NTHi). The design of SARS-CoV-2's spike (S) protein is notable for its ability to facilitate cellular entry via not only the ACE2 receptors but also ICAM-1 which becomes upregulated in a NTHI infection. Technologies used in the development of SARS-CoV-2 were patented by the Spanish National Research Council in 2006 and include methods for creating a SARS-COV vector for gene editing, particularly "gene silencing", and vaccine administration via "virus particles". This patent calls for the engineering of a SARS-COV vector using a helper virus such as HP2 for replication and/or transcription. According to this patent, the said system could be constructed using a genome of SARS-COV containing sequences encoding a heterologous reporter gene or a gene derived from a different infectious agent and the construction of a fulllength cDNA, which in the case of SARS-CoV-2 was most likely performed using hnRNP Q CRISPR Activation Plasmid (h) cDNA. Further, NTHI lysates increase exosome release in the human middle ear epithelial cells. Exosomes can regulate gene expression via their miRNAs. SARS-CoV-2 shares a 76% homology with SARS-COV which is an engineering requirement mentioned in the said patent. The patent also sets forth modification principles and sequences for engineering the ORF of gene 7a. This engineering can be observed as a structural analysis has revealed that SARS-CoV-2 ORF 7a has structural homology with ICAM-1. ORF 7a plays a vital role in virus tropism allowing SARS-CoV-2 to be "guided" to gene editing targets via the hosts inflammatory secretions. Manipulation of ORF 7a to evade the hosts natural defenses against virus tropism as well as the use of NTHI lysates can cause an excessive inflammatory response or a "cytokine storm" in high-risk populations who become infected with COVID-19. This mode of engineering would necessarily classify SARS-CoV-2 a biological weapon.

Glioblastoma (GBM) is the most common and aggressive primary brain tumor in the adult population and it carries a dismal prognosis. Inefficient drug delivery across the blood brain barrier (BBB), an immunosuppressive tumor microenvironment (TME) and development of drug resistance are key barriers to successful glioma treatment. Since gliomas occur through sequential acquisition of genetic alterations, gene therapy, which enables to modification of the genetic make-up of target cells, appears to be a promising approach to overcome the obstacles encountered by current therapeutic strategies. Gene therapy is a rapidly evolving field with the ultimate goal of achieving specific delivery of therapeutic molecules using either viral or non-viral delivery vehicles. Gene therapy can also be used to enhance immune responses to tumor antigens, reprogram the TME aiming at blocking glioma-mediated immunosuppression and normalize angiogenesis. Nano-particles-mediated gene therapy is currently being developed to overcome the BBB for glioma treatment. Another approach to enhance the anti-glioma efficacy is the implementation of viro-immunotherapy using oncolytic viruses, which are immunogenic. Oncolytic viruses kill tumor cells due to cancer cell-specific viral replication, and can also initiate an anti-tumor immunity. However, concerns still remain related to off target effects, and therapeutic and transduction efficiency. In this review, we describe the rationale and strategies as well as advantages and disadvantages of current gene therapy approaches against gliomas in clinical and preclinical studies. This includes different delivery systems comprising of viral, and non-viral delivery platforms along with suicide/prodrug, oncolytic, cytokine, and tumor suppressor-mediated gene therapy approaches. In addition, advances in glioma treatment through BBB-disruptive gene therapy and anti-EGFRvIII/VEGFR gene therapy are also discussed. Finally, we discuss the results of gene therapy-mediated human clinical trials for gliomas. In summary, we highlight the progress, prospects and remaining challenges of gene therapies aiming at broadening our understanding and highlighting the therapeutic arsenal for GBM.

Bacterial contamination in foods and antimicrobial resistance levels of common pathogenic strains causing food-borne disease are important in human health. Thus, typing technologies are important tools to determine primary sources of bacterial contamination. In this study, 40 Escherichia coli strains isolated from 85 food samples were evaluated in terms of genetic diversity, susceptibility to certain antibiotics, and plasmid profiles. Pulsed-field gel electrophoresis was used to identify the genetic relations of E. coli isolates. It was determined that the 40 E. coli strains revealed 32 different pulsotypes represented by 6 subtypes. Antibiotic susceptibility tests conducted by using a disc diffusion method against 15 antibiotics showed that although the isolates revealed 14 different types of resistance profiles, the strains showed the greatest resistance to ampicillin (77.5%), followed by ticarcillin–clavulanic acid (30%), tetracycline (22.5%), and cephalothin (14.5%). Plasmid isolations studies of the strains conducted by the method of alkaline lysis revealed that 18 (45%) of 40 E. coli strains contain 31 different plasmid bands ranging between 64.4 and 1 kb. The results showed that PFGE was a powerful method in tracking sources of food contamination and that the antibiotic resistance levels of food isolates were high and should be monitored.

Keywords: Escherichia coli, pulsed-field gel electrophoresis, antibiotic resistance, genetic diversity, plasmid profiles

Animal cell-based expression platforms enable the production of complex biomolecules such as recombinant proteins and viral vectors. Although most biotherapeutics are produced in animal cell lines, production in human cell lines is expanding. One important advantage of using human cell lines is the increased potential that the resulting biotherapeutics would carry more "human-like" post-translational modifications. Among the human cell lines, HEK293 is widely utilized due to its high transfectivity, rapid growth rate, and ability to grow in a serum-free, suspension culture. In this review, we discuss the use of HEK293 cells and its subtypes in the production of biotherapeutics. We also compare their usage against other commonly used host cell lines in each category of biotherapeutics and summarise the factors influencing the choice of host cell lines used.

Both helper dependent expression systems, based on two components, and single genomes constructed by targeted recombination, or by using infectious cDNA clones, have been developed. The sequences that regulate transcription have been characterized mainly ...

Pseudomonas aeruginosa is a leading cause of bum infections, and antibiotic-
resistant strains of this bacterium are emerging due to extensive application
of antibiotics in the bum unit of hospitals. In this study 50 strains of P. aeruginosa
were isolated from bum patients infected with this micro-organism in the bum
unit of a general hospital in Kerman, Iran over one year [May 1999-ApriI2000].
Sensitivity/ resistance of the isolates for antibiotics and metals was determined
by MIC test. 46% of the isolates were resistant to ciprofioxacin, kanamycin (K),
gentamicin (Gm), tetracycline (Te) and chloramphenicol ( c ). 35% were resistant
to amikacin (AN), ceftriaxone (Ceft), and cefotaxime (CTX), and 10% were resistant
to imipenem (Imp) and piperacillin (PIP). The isolates exhibited varied
MIC's to metal ions. 87% were sensitive to cadmium (Cd), 62% to lead (Pb),
91 % to mercury (Hg), 54% to zinc (Zn), 85% to chromium (Cr), and 83% to
arsenate (Ars). Among them, strain 16 was found to be resistant to Pb, Cr, and Zn
as well as Te, C, Gm, and K. Conjugation and transformation experiments revealed
the transfer of Te', C, Kr and Gmr along with Pbr to a sensitive strain of P.
aeruginosa PTCC1074.1 (Rif) but not to E. coli K12 HBlOl.l (Rif). Subsequent
plasmid isolation and agarose gel electrophoresis (0.7%) confirmed the
presence of three-plasmid bands in strain 16 and the transconjugant. Furthermore,
strain 16 accumulated a maximum amount of Pb (501lM) within 60 min. and
reached a plateau afterwards.

Although several recent studies have focused on the characterization and formulation of adenovirus type 5, similar efforts focusing on adenovirus type 2 (Ad2) have been lacking. To this end, multiple biophysical techniques were employed to investigate the thermal stability of Ad2 as a function of pH. Highly cooperative thermally induced changes in capsid conformation were detected near 45 and 65°C under neutral conditions. The first transition is attributed to the loss of the penton bases and their associated fibers followed by more complete physical degradation at higher temperatures. Data in this work as well as previous studies suggest that a common mechanism of icosahedral virus thermal degradation exists. Conformational changes detected in these studies occurred at increasingly higher temperatures with decreasing pH from 8 to 5 suggesting that the physical stability of Ad2 is enhanced under mildly acidic conditions. To consolidate the data generated in these studies, a multi-dimensional Eigenvector approach was employed to generate an empirical phase diagram (EPD) of Ad2. The EPD identifies conditions, or “phase boundaries,” where structural integrity is altered, in addition to providing a tool that can be used to identify conditions under which forced degradation and excipient-screening studies can be conducted. © 2006 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 95: 1469–1479, 2006

The study was carried out to assess pastoralists and agro-pastoralists awareness, knowledge and practice in
various livestock diseases affecting domestic animals in Arusha Manyara and Morogoro regions in Tanzania.
Closed- and open-ended questionnaires, focus group discussions and in-depth interview techniques were
employed. Diseases, drought, lack of dipping tanks, insufficient of livestock experts and drugs are the main
constraints in the livestock keeping community in the study area. Nineteen diseases have been reported to affect
their animals at one time or the other. East Coast fever (ECF, 79.7%), Contagious Caprine Pleuropneumonia
(CCPP, 60.8%) and Trypanosomosis (50%) have been reported by more than 50% of pastoralists that they affect
their animals. ECF and CCPP seem to be the leading diseases with great impact to the pastoralists by causing
high mortality rates. Rift valley fever (RVF) and anthrax have been reported by majority to be diseases which
appear in form of outbreak in their area. Diseases reported here are said to be controlled primarily by treating
with various drugs and Oxytetracycline being a common drug of choice for most unknown diseases. Other
control methods include vaccination and deworming, dipping and spray of animals using acariceides. Livestock
experts have been reported to play little role in controlling common livestock diseases as majority of livestock
keepers tends to treat their animals. Veterinary experts seem to be important during outbreak of diseases or for
unknown diseases killing many animals. Eating of dead and improperly cooked meat together with un-boiled
milk was found to be common in the pastoral community. This could lead to the spread (if any) of zoonotic
diseases easily. Livestock keeping community is aware of most of common diseases circulating in their area but
the way they practice to control leads to failure of control of those diseases at individual and national level.
Devising a mechanism to educate them so that they know how to handle some common and reporting outbreak
diseases such as use of trained community animal health workers (CAHWs) will help control livestock diseases
in Tanzania.

Actualización de la bacteriología clínica moderna, se describen las bacterias que producen patología infecciosas y se estudia cada género bacteriano de importancia médica desde la perspectiva de su reciente ubicación taxonómica.
ISBN: 958-683-052-7

Gene therapy has ceased to be a futuristic dream and has become a treatment for the present. Somatic cells can be treated with gene replacements or gene fragments to express required proteins and whilst gene therapy was originally aimed at inherited disease it now treats a number of acquired complaints like cancer and HIV. Originally delivered through viruses there are now safer direct or biochemical vectors and in the future nano-particles might deliver the drug of choice straight to the nucleus of the affected cells.

The emphasis of this study was on the sensitivity of the antibiotics to pathogenic bacterial strains of methicillin resistant Staphylococcus aureus (MRSA). Total of 280 samples were collected in microbiology laboratory of Sheikh Zayed Hospital, Lahore. Staphyloccus aureus was isolated by using Blood agar, Nutrient agar, Mannitol salt agar, Catalase, Coagulase and Dnase tests. Anti PBP-2a latex agglutination test was used to identify MRSA. Out of 139 Staphylococcus aureus strains isolated from various clinical samples, 43.16% were found to be methicillin resistant. The efficacies of these isolates were tested by paper disc diffusion method on Mueller Hinton agar. All MRSA isolates were resistant to penicillin. Among MRSA isolates, 44.82% were from different inpatient departments, whereas, 40.43% of the MRSA isolates were from outpatients. This preliminary report showed a high prevalence of MRSA in the hospital. To reduce the prevalence of MRSA, regular surveillance of hospital acquired infections is the need of the hour. Keywords: Methicillin resistant, Staphylococcus aureus, Anti PBP-2a, latex agglutination test, Paper disc diffusion method

ABSTRACT
Background: For the past two decades, Acinetobacter spp. have emerged as an important
pathogen globally in various infections. Objectives: This study was conducted to determine the
frequency, risk factors, and antibiotic resistance pattern of Acinetobacter spp. from various clinical
samples. Materials and Methods: This retrospective, hospital record–based, cross‑sectional study
included a total of 8749 clinical samples collected from patients at a tertiary care hospital in Odisha,
India from July 2010 to December 2012. The samples were processed and identified by standard
protocol. The Acinetobacter isolates were tested for antibiotic resistance by Kirby‑Bauer disk
diffusion method [according to the Clinical and Laboratory Standards Institute (CLSI) guidelines].
Results: From 8749 clinical samples, 4589 (52.5%) yielded significant growth and only 137 (3%,
137/4589) Acinetobacter spp. were isolated. Maximum (56.9%) isolates were obtained from pus/
swab, followed by blood (13.1%) and urine (12.4%). Elderly age, being inpatients, longer duration of
stay in the hospital, associated co‑morbidity, and invasive procedure were found to be significant risk
factors in the setup investigated (P is less than 0.05). Out of 137 isolates, 75 (54.7%) were resistant
to more than three classes of antibiotics (multidrug resistant) and 8 (5.8%) were resistant to all
commonly used antibiotics (pan‑drug resistant). Majority of the isolates were sensitive to imipenem,
meropenem, and piperacillin/tazobactam, and showed resistance rates of 19%, 22%, and 23%,
respectively. All eight pan‑drug resistant isolates were 100% sensitive to colistin. Conclusion: This
hospital‑based epidemiological data will help to implement better infection control strategies and
improve the knowledge of antibiotic resistance patterns in our region.
Key words: Acinetobacter species, antibiotics, frequency, resistance, risk factors

A new clustering algorithm that uses a weighted Mahalanobis distance as a distance metric to perform partitional clustering is proposed. The covariance matrices of the generated clusters are used to determine cluster similarity and closeness so that clusters which are similar in shape and close in Mahalanobis distance can be merged together serving the ultimate goal of automatically determining the optimal number of classes present in the data. Properties of the new algorithm are presented by examining the clustering quality for codebooks designed with the proposed method and another common method that uses Euclidean distance. The new algorithm provides better results than the competing method on a variety of data sets. Application of this algorithm to the problem of detecting suspicious regions in a mammogram is discussed.

http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=710194&tag=1

This paper studies the space vector pulse width modulation technique (SVPWM) for the three-phase threelevel nine switches voltage source inverter. The proposed inverter is based on the two level inverter topology where it consists of a main inverter switches Q1, Q2, Q 3, Q4, Q5, and Q6, an auxiliary three bidirectional switches S1, S2, and S3 and two capacitor banks C1, and C2. Ideal switches and diodes will be assumed and the dc bus capacitor bank voltages fluctuations will be absent. The effectiveness of the SVPWM control scheme will be verified by the simulations results in the worst case where two very low switching frequencies values of 1 kHz and 5 kHz will be considered. Open loop controller experimental measurements at 1 kHz switching frequency will be provided.

http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=4562305