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Dipole-Quadrupole Theory of Surface Enhanced Raman Scattering - A M Polubotko - Bog - Nova Science Publishers Inc - Plusbog.dk

Dipole-Quadrupole Theory of Surface Enhanced Raman Scattering - A M Polubotko - Bog - Nova Science Publishers Inc - Plusbog.dk

This book is devoted to explanation of SERS in terms of the strong dipole and especially quadruple light-molecule interactions arising in surface fields strongly varying in space in the region of strongly irregular surface roughness. The influence of the quadruple interaction is a matter of principle, since it provides explanation for the appearance of forbidden bands arising in a great number of experiments on SERS on symmetrical molecules. This essential detail in fact is absent in all other SERS theories, that does not permit to create a closed theory, which explains the majority of experimental facts accompanying SERS by a unitary approach. Moreover as it is demonstrated in the book the huge enhancement in the phenomenon of Single Molecule Detection by the SERS method can be explained exclusively by the strong quadruple light-molecule interaction. The first part of the book is devoted to a brief description of main SERS characteristics and critical analysis of theoretical approaches. Further the theory of electromagnetic field near some model kinds of rough surfaces and some other systems and the theory of the SER cross-section for arbitrary and symmetrical molecules are presented in detail. The obtained expressions helps to establish selection rules for contributions in the SER cross-section and analyse the SER spectra of symmetrical molecules. This analysis corroborates main specific features of the SER spectra of symmetrical molecules and some anomalies, which exist in these spectra for some specific conditions. The existence of electrodynamic forbiddance of the quadruple scattering mechanism for the methane molecule and molecules with cubic symmetry groups is established. The above theory permits to explain not only the huge enhancement in the phenomenon of Single -Molecule Detection but the blinking of the SERS signal too. The first layer effect, arising in the first layer of absorbed molecules also is considered in detail. It appears that the nature of this phenomenon is the electrodynamic enhancement, which is very large just in the first layer. The other phenomena, accompanying SERS are accounted for. It is demonstrated that the theory is in a good agreement with the SERS experiments and explains quite a number of characteristics related to the SERS phenomenon.

DKK 534.00
1

Molecular Recognition - - Bog - Nova Science Publishers Inc - Plusbog.dk

Molecular Recognition - - Bog - Nova Science Publishers Inc - Plusbog.dk

In the monograph recognition of the receptors by drugs is described as a complex phenomenon that has not been yet entirely understood. The description of molecular structure information necessary to achieve specific receptor without getting lost among huge amounts of non-specific acceptors is present. Various examples of receptor'' binding features for narcotic analgetics, neuroleptics, tranquilisators, ligands of acetylcholine receptors. The three stages of drug interaction with acceptors are considered, namely, distant stage, stage of orientation of the molecule on the acceptor, stage of molecule fixation. Kinetics and thermodynamics of these stages as well as factors preventing drug binding to non-specific acceptors are described. Some considerations concerning methods of changing activity and selectivity of drugs are given. Literature information needed for analysis of molecular mechanisms of interactions between drugs and receptors is present.

DKK 1079.00
1

Pharmacological Aspects of Molecular Recognition - - Bog - Nova Science Publishers Inc - Plusbog.dk

Pharmacological Aspects of Molecular Recognition - - Bog - Nova Science Publishers Inc - Plusbog.dk

In the monograph, recognition of the receptors by drugs is described as a complex phenomenon that has not been yet entirely understood. The description of molecular structure information necessary to achieve specific receptors without getting lost among huge amounts of non-specific acceptors is present. Various examples of receptor'' binding features for narcotic analgetics, neuroleptics, tranquilisators, ligands of acetylcholine receptors. The three stages of drug interaction with acceptors are considered, namely, distant stage, stage of orientation of the molecule on the acceptor, stage of molecule fixation. Kinetics and thermodynamics of these stages as well as factors preventing drug binding to non-specific acceptors are described. Some considerations concerning methods of changing activity and selectivity of drugs are given. Literature information needed for analysis of molecular mechanisms of interactions between drugs and receptors is present.

DKK 588.00
1

Crystal Violet - - Bog - Nova Science Publishers Inc - Plusbog.dk

Crystal Violet - - Bog - Nova Science Publishers Inc - Plusbog.dk

Crystal Violet: Production, Applications and Precautions opens by presenting the main factors influencing the metachromatic phenomenon. The hypsochromic effect is due to the symmetry of the molecule providing the common electronic signal around the central carbon atom. Next, the authors discuss further modification of the adsorbents in an effort to improve their adsorption capacity and make them feasible for use in field applications. The closing chapter reports on the removal of crystal violet dye from water using surfactant-modified zeolite from coal fly ash, surfactant-modified zeolite from coal bottom ash and nanosilica from sugarcane waste ash.

DKK 757.00
1

Can't Live Without It - Loren Hazelwood - Bog - Nova Science Publishers Inc - Plusbog.dk

Can't Live Without It - Loren Hazelwood - Bog - Nova Science Publishers Inc - Plusbog.dk

Why is blood red? Because it contains Haemoglobin -- the most important molecule in the human body. In health -- the average person has 4 lbs. of haemoglobin and manufactures seven billion molecules of haemoglobin every second. It carries oxygen from the lungs to the cells and helps the body remove waste carbon dioxide. In sickness -- an estimated one billion people around the world have some disorder related to haemoglobin: sickle-cell anaemia, pernicious anaemias, iron-deficiency anaemia, porphyries, haemoglobin E disease, alpha-thalassemia, beta-thalassemia, and G6PD deficiency. One type of haemoglobin can be used to monitor diabetes. This basic introduction to haemoglobin includes information on the reselection of Richard Nixon, the madness of King George III, werewolves, lead poisoning, legends about Pythagoras, genetics and genetic screening, diabetes, respiration, the production of red cells, and translation of the DNA code. Haemoglobin is a fascinating molecule that touches our lives, our politics, our myths and our history. This new book presents current analyses of one of the most controversial issues of our times -- affirmative action. Proponents on both sides of the issue claim clear-cut evidence for the rightness of their arguments, yet evidence is hazy at best. This volume helps shed light on the underlying basis for affirmative action and elucidates the latest legal and social developments.

DKK 436.00
1

Fourier Transform Infrared Spectroscopy - - Bog - Nova Science Publishers Inc - Plusbog.dk

Fourier Transform Infrared Spectroscopy - - Bog - Nova Science Publishers Inc - Plusbog.dk

Fourier Transform Infrared Spectroscopy (FTIR) is a powerful tool for identifying types of chemical bonds in a molecule by producing an infrared absorption spectrum that is like a molecular "fingerprint". FTIR is most useful for identifying chemicals that are either organic or inorganic. It can be utilised to quantitate some components of an unknown mixture, as well as to the analysis of solids, liquids, and gasses. This book presents topical research in the field of FTIR including an overview of recent applications of FTIR spectroscopy in combination with chemometrics in the analysis of various quality parameters of fats and oils, a modified FTIR method for the analysis of various structural dynamic problems and energetic materials on surfaces.

DKK 890.00
1

Hyaluronic Acid - - Bog - Nova Science Publishers Inc - Plusbog.dk

Hyaluronic Acid - - Bog - Nova Science Publishers Inc - Plusbog.dk

Hyaluronic acid, or hyaluronan, is a water soluble, anionic extracellular matrix glycosaminoglycan polymer with variable molecular weight that determines its physiological role, rheological properties and applications. Since its discovery in the early 1930s, there has been an increased awareness concerning the biology of hyaluronic acid, its signaling pathways and its role in the biomedical and cosmeceutical industry. Being an endogenous molecule, hyaluronic acid is biocompatible, biodegradable, and has strong mucoadhesive, viscoelastic properties. The authors provide chemical modification approaches to hyaluronic acid, as well as address the magnitude of applications of hyaluronic acid-based targeted drug vectors and patents. The closing study discusses glycosaminoglycans, a specialized group of unbranched, anionic disaccharide polymers attached by a covalent linkage to the membrane proteins via sulphate groups in their sugar moieties.

DKK 624.00
1

Gene Mutations - - Bog - Nova Science Publishers Inc - Plusbog.dk

Gene Mutations - - Bog - Nova Science Publishers Inc - Plusbog.dk

A gene is a DNA sequence that can be transcribed into an RNA molecule and transferred to offspring organisms. Changes in DNA sequences that determine the structure and function of a gene are called mutations. Gene Mutations: Causes and Effects opens by exploring the physical, chemical, and biological agents that cause mutations interact with DNA, leading to genetic instability. Recent advances in next-generation sequencing have led to the discovery of new causative genes or those mutations. The authors describe the phenotypes and gene mutations, discussing genotype-phenotype correlations compared with previous reports. Lastly, one study analyses all conflicting data concerning the amplification of the ESR1 gene, particularly its ambiguous prevalence in both untreated tumors and tumors either responsive or unresponsive to antiestrogen therapy.

DKK 757.00
1

Biomacromolecular Mass Spectrometry Research - - Bog - Nova Science Publishers Inc - Plusbog.dk

Biomacromolecular Mass Spectrometry Research - - Bog - Nova Science Publishers Inc - Plusbog.dk

Mass spectrometry has proven its applicability to the measurement of almost any molecule. However, different substances require special knowledge in the respective field and scientists tend to focus on their particular task in collaborations and meetings. Nevertheless, disciplines have become more and more interdisciplinary and scientists now have to acquire knowledge in many scientific fields other than our own. Especially mass spectrometrists, who often find them selves learning about the history of their sample, be it from a zoologist, clinician, microbiologist, or biochemist. This was evident with the rise of proteomics, which reaches across species and research projects, uniting scientists through the methodology. This book presents research from around the globe in the fields of biomacromolecules such as proteins, DNA, and other biopolymers studied with mass spectrometry.

DKK 890.00
1

Biomacromolecular Mass Spectrometry Research - Simone Konig - Bog - Nova Science Publishers Inc - Plusbog.dk

Biomacromolecular Mass Spectrometry Research - Simone Konig - Bog - Nova Science Publishers Inc - Plusbog.dk

Mass spectrometry has proven its applicability to the measurement of almost any molecule. However, different substances require special knowledge in the respective field and scientists tend to focus on their particular task in collaborations and meetings. Nevertheless, disciplines have become more and more interdisciplinary and scientists now have to acquire knowledge in many scientific fields other than their own. Especially mass spectrometrists, who often find themselves learning about the history of their sample, be it from a zoologist, clinician, microbiologist, or biochemist. This was evident with the rise of proteomics, which reaches across species and research projects, uniting scientists through the methodology. This new book presents research from around the globe in the fields of biomacromolecules such as proteins, DNA, and other biopolymers studied with mass spectrometry.

DKK 890.00
1

Current Advances in Sleep Biology - - Bog - Nova Science Publishers Inc - Plusbog.dk

Current Advances in Sleep Biology - - Bog - Nova Science Publishers Inc - Plusbog.dk

The mystery of sleep has fascinated scientists for decades, yet despite great advances on several fronts, basic questions about sleep remain unanswered. What neural or somatic mechanisms govern the normal alternation between sleep and wakefulness? What genes control the quality and quantity of sleep? Do all animals sleep and if so, do similar biological mechanisms govern sleep in different animal species? And, perhaps most critically, what are the functions of sleep? In this book, leading scientists explore these fascinating questions by presenting their latest findings spanning a) neurological structures and genes underlying sleep expression b) interactions between sleep and the immune system c) the evolution of sleep in invertebrate species and d) the role of sleep in neurogenesis, macro-molecule synthesis and brain plasticity in both developing and adult animals.

DKK 1034.00
1

Hyaluronic Acid - - Bog - Nova Science Publishers Inc - Plusbog.dk

Hyaluronic Acid - - Bog - Nova Science Publishers Inc - Plusbog.dk

This book offers a valuable clinical resource for health professionals and researchers. It gives an overview about the pivotal role played by High Molecular Hyaluronic Acid (HMW-HA) during pregnancy and its applications in the gestational period. Hyaluronic acid is a critical component of the extracellular matrix (ECM) and one of the most interesting, versatile and useful natural molecules in almost all areas of biology. As widely reported, HA has a pivotal role in several phases of pregnancy, from fertilisation to labour and it displays several regulatory activities and functional properties based on its different molecular weight. While low molecular weight hyaluronic acid (LMW-HA) is widely used in gynaecology for menopause-related symptoms or in association with physical treatments (eg: radiation therapy) to counteract the onset of adverse events, HMW-HA has been poorly evaluated as clinical treatment. Its physiological presence in the extracellular matrix of all the main organs and tissues involved in pregnancy (uterus, cervix, placenta, decidua, chorion, amnios, ovarium etc..) suggests the importance of this molecule for a successful gestation. Several papers, in particular, shed light on its importance for blastocyst adhesion and implantation, for an efficient immune tolerance and for the correct development of haemo-lymphatic system. It has been demonstrated that HMW-HA has regulatory activity on the PGRMC1 expression, a specific progesterone receptor expressed in maternal and foetal-maternal interface tissues, involved in uterine quiescence. On these premises, the administration of HMW-HA may represent an interesting treatment opportunity for the prevention of recurrent miscarriage and pre-term birth (PTB) in patients with risk factors. The high safety profile of HMW-HA further supports its administration in pregnancy. All these interesting topics will be discussed and deepened in this book, giving the opportunity to explore in detail every aspect of this effective and attractive molecule, thus helping physicians to assess the state of connective tissues in pregnancy and to evaluate the risk for the onset of gestational complications.

DKK 718.00
1

Coenzyme Q10 - - Bog - Nova Science Publishers Inc - Plusbog.dk

Coenzyme Q10 - - Bog - Nova Science Publishers Inc - Plusbog.dk

Coenzyme Q10: Uses, Health Effects and Role in Disease reviews the current knowledge and evidence of the potential clinical applications of Coenzyme Q10 (CoQ10). CoQ10 is a lipophilic molecule composed by a bezonquinone ring conjugated to a ten-carbon isoprenoid side chain. It exists in two molecular forms, ubiquinone and ubiquinol, which are the basis for its antioxidant properties. CoQ10 also plays an essential role in cellular metabolism to produce ATP, which provides energy for muscle contraction and other vital cellular functions. Most of the ATP production occurs in the inner mitochondrial membrane, where coenzyme Q is found. The authors review the protective effects of CoQ10 on intense physical exercise, reducing muscle damage and improving physical performance. Evidence of secondary CoQ10 deficiency in disease and in pharmacotherapy is discussed, highlighting putative mechanisms to account for this deficit together with examples of therapeutic intervention. Secondary CoQ10 deficiencies are important to identify as clinical benefit can be elicited following treatment with CoQ10 or its associated analogues.

DKK 820.00
1

Diols - - Bog - Nova Science Publishers Inc - Plusbog.dk

Diols - - Bog - Nova Science Publishers Inc - Plusbog.dk

Diols: Synthesis and Reactions discusses the applications of the gem-diol chemical group in organic synthesis and atmospheric processes, as well as their effects on odorant receptors and on the catalytic sites of enzymes. Following this, the reactions of cyclophosphazenes are studied using numerous diols, leading to the formation of regioisomers; open chain, spiro, ansa and bridged-structures and their mixtures. This investigation has many advantages in terms of obtaining products with high yield, ease of isolation and high reactivity potential. Additionally, the authors review the hydrogenation of cis-2-butene-1,4-diol over supported metal catalysts, with particular emphasis on the different reaction mechanisms. cis-2-Butene-1,4-diol is an interesting multifunctional substrate, chosen as a probe molecule to study the liquid phase hydrogenation of unsaturated diols due its versatility. The closing chapter presents a global review of the level of molecular complexity that can be synthetized from accessible reagents: amines and diols. Acceptorless dehydrogenative condensations will also be explored in view of their applications in the synthesis of heterocycles.

DKK 890.00
1

The Essential Guide to Lewis Acids - Oliver M. Sandes - Bog - Nova Science Publishers Inc - Plusbog.dk

The Essential Guide to Lewis Acids - Oliver M. Sandes - Bog - Nova Science Publishers Inc - Plusbog.dk

Lewis acids have been utilized to activate molecules, whether it be the generation of a simple Lewis acid-base adduct or the coordination and activation of a substrate molecule in a catalytic transformation. When designing new Lewis acids, a synthetic chemist has to consider the properties of the Lewis acid. As such, this compilation describes the methods used in measuring Lewis acid strength, including a ladder diagram comparing the Lewis acid strength of both main group and metal-based Lewis acids. Since carboxylic acid derivatives are commercially available, non-toxic, cheap and normally stable to air and moisture, carboxylic acid derivatives are ideal reactants for synthetic strategy. The decarboxylative coupling reaction is discussed as one of the most important tools for organic synthesis, and remarkable progress has been made in this field. In conclusion, the authors highlight recent advances achieved in the development of processes for esters production from glycerol and terpenic alcohols in metal salts-catalyzed reactions, using acetic acid as the carbonylic reactant. The effects of main reaction parameters such as concentration, temperature and reactants stoichiometry are assessed. A comparison with traditional acid catalysts used in these reactions is also performed.

DKK 718.00
1

Lifetimes of Fluorinated Compounds - Akira Sekiya - Bog - Nova Science Publishers Inc - Plusbog.dk

Lifetimes of Fluorinated Compounds - Akira Sekiya - Bog - Nova Science Publishers Inc - Plusbog.dk

Rate constants for reactions of 11 hydrochlorofluorocarbons and 12 hydrofluorocarbons were measured by means of the absolute rate method over the temperature range 250-430 K. OH radicals were generated by flash photolysis, laser photolysis, or a discharge flow methods; and the concentration of OH radicals was monitored by means of the laser-induced fluorescence technique. The fluorinated compounds were purified by gas chromatography; impurities remaining in the samples after purification were found to have no sizeable effect on the measured rate constants. The Arrhenius rate expressions were determined from the kinetic data obtained in this study as well as from available literature data. A method for estimating rates of reactions with OH radicals using an artificial neural network method was developed. An algorithm for a back-propagation method for determining optimised weights was developed for cases in which the reactivities of individual reaction sites of a molecule are not known. The ability of the neural network method to predict rate constants was evaluated by using the leave-one-out method. Rate constants for 94 compounds, including hydrocarbons, hydrofluorocarbons, hydrochlorofluorocarbons, hydrochlorocarbons, and brominated compounds, were calculated within a factor of 2.

DKK 514.00
1

Organic Polymers - - Bog - Nova Science Publishers Inc - Plusbog.dk

Organic Polymers - - Bog - Nova Science Publishers Inc - Plusbog.dk

In this compilation, examples of film polymeric composites based on azobenzene polymers and metallic complexes for use in electro-optical modulators and recording media for polarization holography are considered. It is shown that the information characteristics of the investigated media are mainly influenced by the structure of the azobenzene groups (electron-donor and electron-acceptor substitutes) and by the supramolecular structure of the polymers. Following this, precise analyses of the molecular arrangement of three-dimensional crystals, two-dimensional molecular films, and interfacial particle layers of polyguanamine derivatives with a high refractive index are been performed. It is determined that the high refractive index of the polyguanamine derivatives is not caused by the chemical structure of the molecule, but is based on the packing of molecular chains or the refraction of transmitted light due to the difference in electron density between the crystalline and amorphous regions. In the closing chapter, organic-inorganic hybrid polymers are applied in different fields, including adsorption of metals from aqueous media. In this context, two organic-inorganic hybrid polymers were prepared by sol-gel method, using proportions of 1:1 and 1:3 of the monomer 1-vinylimidazole and the silane agent 3-mercaptopropyl-trimethoxysilane, respectively, in order to evaluate the proportion effect of VI and MPTMS on Hg2+ ions adsorption from an aqueous solution.

DKK 718.00
1

Nature of Water - Natale Gaspare Santo - Bog - Nova Science Publishers Inc - Plusbog.dk

Nature of Water - Natale Gaspare Santo - Bog - Nova Science Publishers Inc - Plusbog.dk

Water, the most represented substance in the human body, is a trace of the primordial sea where life originated. Its virtues may be represented by the Venus of Botticelli coming out from the sea, as well as by Velasquez''s water seller and by Aristophanes'' chant of the clouds. Water has been connected with medicine from time immemorial and is a common good. For Sumerians, the physician was the man who new water. Homer''s (850-750 BC) mythical tradition made Ocean and Thetys progenitors of all gods and of the world. Hesiod (ca. 700 BC) chanted Poseidon, the sea-lake god, who could cause tempests and seaquakes, generate springs, and also confer the power to walk on water like on earth. In the last century, at the time of the cold war, the information was generated in Moscow about the discovery of polywater, a new form of water, which could be produced in tiny drops in very thin tubes. Astonishingly it boiled at 200 °C and had an initial freezing point of around -30 °C. Polywater was a case for concern among states because of its potential capability to pollute normal water. Finally it was demonstrated that it was just an artifact due to contamination. Jacques Benveniste, a French immunologist of good reputation came to the conclusion that water saved the memory, being imprinted like a cast. However stringent experiments performed at suggestion of the Editor, showed that water could not act as a template for its molecule.

DKK 805.00
1

Sunitinib - - Bog - Nova Science Publishers Inc - Plusbog.dk

Sunitinib - - Bog - Nova Science Publishers Inc - Plusbog.dk

Tyrosine kinase inhibitors are used to treat patients with advanced thyroid cancers. Sunitinib (SU11248) is an oral small-molecule, oxindol derivative, multi-targeted tyrosine kinase inhibitor that inhibits receptors for platelet-derived growth factor and vascular endothelial growth factor receptors, growth factor receptor, fms-related tyrosine kinase 3, RET oncogene and a multitargeted tyrosine-kinases. In Sunitinib: Mechanisms, Interactions and Side Effects, the authors report nine open-label studies carried out with sunitinb wherein the drug showed its anti-tumoral activity in advanced differentiated thyroid carcinoma, advanced tumors refractory to radioiodine and in medullary thyroid carcinoma, in phase II trials and in retrospective studies.The aim of the following chapter is to summarize the published results of clinical research focused on the use of sunitinib in pediatric oncology and to supplement it with the experience from the authors clinical practice. Suggestions appearing in case reports and clinical trials indicate that sunitinib may be a valuable drug also in pediatric clinical oncology. More attention should be paid to the selection of the most suitable indications, patients, and doses to balance the efficacy and safety in children with malignant diseases.The concluding review offers a comprehensive overview of phases I and II studies investigating clinical efficacy, tolerability and safety of sunitinib for the treatment of ovarian cancer (OC). Sunitinib was tested in OC due to increasing incidences of resistance to chemotherapy in diseases which have a poor prognosis. Further trials are required to better understand the efficacy of this drug. Regarding its safety-profile, hematologic and non-hematological adverse events are common, but generally not clinically significant.

DKK 1034.00
1

Pharmacological Activity-Based Quality Control of Chinese Herbs - Stefano Parodi - Bog - Nova Science Publishers Inc - Plusbog.dk

Pharmacological Activity-Based Quality Control of Chinese Herbs - Stefano Parodi - Bog - Nova Science Publishers Inc - Plusbog.dk

Natural products are the most successful source of drugs. Of the 877 small-molecule new chemical entities introduced between 1981 and 2002, roughly half were natural products, semi-synthetic natural product analogues or natural mimics. Chinese herbs (traditional Chinese medicines, TCMs) have been used for prevention and treatment of diseases for thousands years. It has been attracting intensive attention in the trends of back to nature. As herbal medicines, the conditions of growth, harvest time, process and storage etc. will undoubtedly affect the presence and concentration of the bioactive constituents, thus affecting their quality and efficacy. Up to date, there are few books focussing on the relationship, which is the bridge between TCM and modern medical science, of traditional clinic uses, pharmacological activities and quality control of Chinese herbs. Unfortunately, bioactive compounds in Chinese herbs are usually not or only partially known. Actually, the active compounds considered in Chinese herbs may be different according to their clinical indication. In addition, it is considered that the curative effect of Chinese herbs is an integrative result of a number of bioactive compounds. Therefore, how to control the quality is a big problem. We would like to discuss the quality control based on their traditional clinical uses and pharmacological activities in this book, which is the fundamental step towards developing and modernising such products into evidence based medicines. It will also help the peoples to understand TCMs in modern scientific angles. This book is designed primarily as a textbook for or adjunct to course in herbal remedies, food safety or quality control of herbs. It is also a professional reference whom is in the area of drug discovery, pharmaceutical analysis and food chemistry.

DKK 1029.00
1

Atherosclerosis - Silvana Jovanova - Bog - Nova Science Publishers Inc - Plusbog.dk

Atherosclerosis - Silvana Jovanova - Bog - Nova Science Publishers Inc - Plusbog.dk

Atherosclerosis is a chronic inflammatory disease that affects medium and large-sized arteries. It begins after birth and the progression depends on several factors - traditional triad: hypertension, hyperlipidemia and diabetes mellitus, then age, sex, smoking and sedentary life-style. At the beginning atherosclerosis is asymptomatic and we cannot estimate appropriately its frequency, but its complications - coronary artery diseases, cerebrovascular diseases, peripheral arterial diseases, which occur late, are responsible for more than half of the yearly mortality in the world. Unfortunately, sudden cardiac death may be the first clinical manifestation. The incipient event is endothelial dysfunction, as a result of injury, caused by high level of cholesterol [especially w-density-lipoprotein LDL], hyperglycemia, hypertension, smoking, infectious agents, and toxins. Endothelial cells overexpress adhesion molecules - vascular cell adhesion molecule-1 [VCAM-1] and increases recruitment of inflammatory cells - monocytes [Mo], T-cells and subsequent release of monocyte chemo-attractant protein-1 [MCP-1] that results in additional leucocytes recruitment. Injured endothelium allows migration of inflammatory cells that release cytokines and lipids into the intima. That leads to cytokine-mediated progression of atherosclerosis and oxidation of LDL. Macrophages [MP] take up oxi-LDL and form foam-cell. They have metabolic activity and produce cytokines, proliferation of smooth muscle cells and formulate athero-fibrose plaque. Atherosclerotic plaque is composed of superficial layer - fibrose cap and lipid core, that consists of foam cells, extracellular lipid and necrotic cellular debris. It progresses as a result of accumulation of lipid and proliferation of smooth muscle cells and results in luminal narrowing of the arteries which leads to compromised blood and oxygen supply to the tissues. The gradually growing atherosclerotic plaques have thick fibrose cap and are stable. They cause symptoms of stable angina. Rapidly growing plaques cause unstable coronary artery disease. These plaques are mainly composed of lipids and have tiny fibrose cap that is prone to fissuring or rupture. Intraplaque hemorrhage from microvessels in plaque initiate platelet adhesion and activation of coagulation cascade that leads to platelet thrombus formation, i.e. promote thrombogenesis. Knowledge of the pathogenesis of the atherothrombosis modifies the diagnostic and therapeutic approach. Conclusion: Attention should be focused on the management of three points: 1. Endothelial dysfunction [correction of modified risk factors: hypertension, hyperlipidemia, diabetes mellitus, life-style-smoking, physical activity and food], 2. Atherosclerosis [modification of the inflammatory cascade, i.e. elimination of inflammatory pathways and inhibition of oxidation of LDL], 3. Thrombogenesis [inhibition of platelet adhesion, activation and aggregation].

DKK 445.00
1

Aromaticity - Maria J Gonzalez Moa - Bog - Nova Science Publishers Inc - Plusbog.dk

Aromaticity - Maria J Gonzalez Moa - Bog - Nova Science Publishers Inc - Plusbog.dk

Aromaticity is among the most frequently used concepts in the chemical literature. Nevertheless, it has to be stressed that aromaticity is not an observable that could be directly obtained from molecular wave function. So, it remains as a controversial concept and its physical origin is still being debated. This has lead to multiple ways for assessing the aromatic or anti-aromatic character of molecules. Thus, several indices of aromaticity have been proposed throughout the literature. It is well-known that aromaticity is strongly related to the electron delocalisation of the electrons along all the centres of the ring. The introduction of the n-order density matrix, and development of n-centre delocalisation indices (n-DIs), has provided a quantitative tool to measure electron delocalisation within a certain ring. Therefore, n-DIs can be regarded as a promising way to determine the actual role played by electron delocalisation in aromaticity. n-DIs are found to be in line with most of the qualitative trends predicted by the harmonic oscillator model of aromaticity indices, HOMAs, aromaticity indices derived from the Chemical Graph Theory, properties of the ring critical points, and circuit resonance energies. It has to be noticed that the direct comparison of n-DIs computed for rings with a different number of centers does not provide a picture of relative aromatic stabilisation. In fact, aromatic stabilisation does not only depend on the extension of the electron delocalisation over the n centres, but also on the number of centres. n-DIs dependence on the number of centres and electrons in a ring prevents to use their direct comparison as a measure of aromatic stabilisation unless an appropriate scaling is applied. Effective Scaled Electron Delocalisation indices, ESED, have been developed for comparing the total aromaticity of polyaromatic hydrocarbons. n-DIs exhibit very different behaviour for aromatic and antiaromatic hydrocarbons. Thus, an aromatic compound is one whose multicenter electron delocalisation is larger than that of the corresponding linear structure, whereas an antiaromatic compound is one where the multi-centre electron delocalisation is smaller than that of the linear molecule. Those compounds that display very small differences between linear and cyclic structures may be called non-aromatic. n-DIs are also found as a promising tool to study the aromaticity of transition states in concerted processes. This book also reports on its application to the study of the aromaticity in all metal compounds.

DKK 514.00
1

Hepatitis B Virus Research Focus - Lihong Ye - Bog - Nova Science Publishers Inc - Plusbog.dk

Hepatitis B Virus Research Focus - Lihong Ye - Bog - Nova Science Publishers Inc - Plusbog.dk

Hepatitis B virus (HBV), discovered in 1966, infects more than 350 million people in the world. The infection of HBV is a leading cause of chronic carriage of the virus and progressive liver diseases, such as hepatitis, liver cirrhosis and hepatocellular carcinoma (HCC). HBV consists of a circular, partially double-stranded DNA molecule of 3.2 kb in length, which contains four overlapping reading frames that code for surface proteins (HBsAg), core proteins (HBcAg/HBeAg), the viral polymerase, and the transcriptional transactivator X protein. Chronic hepatitis appears to be due to a suboptimal cellular immune response that destroys some of the infected hepatocytes and does not purge the virus from the remaining infected hepatocytes, thereby permitting the persisting virus to trigger a chronic indolent necroinflammatory liver disease that sets the stage for development of HCC. However, the mechanisms responsible for malignant transformation in chronic HBV infection are not well defined, and both viral and host factors have been implicated in the process. All cases of HCC occur after many years of chronic hepatitis which could, theoretically, provide the mitogenic and mutagenic environment to precipitate random genetic and chromosomal damage, and lead to the development of HCC. Hepatitis B virus X protein (HBx), an important transforming inducer, plays a crucial role in HCC development. HBx has the capability to influence a variety of signal transduction pathways within the cells. Monitoring of the HBV genotypes and antibody to Hepatitis B x antigen (anti-HBx) are significant for predicting early diagnosis of liver cirrhosis and HCC. HBV and Hepatitis C virus or HIV coinfections can accelerate the course of chronic liver disease and facilitate progression to cirrhosis and HCC. As for therapy of liver diseases, five drugs are now FDA-approved for the treatment of HBV, including interferon (IFN), lamivudine, adefovir, entecavir, and peginterferon alfa-2a. Moreover, the prevention for HBV infection is very important. It is likely that the most important outcome of the research on HBV has been the invention, development, and application of the vaccine against HBV. However, at present most investigators focus on basic research rather than practical applications. The HBV research should be focused on animal models and clinical practice. The technology update in HBV research and the multisubject combination may be attached importance to next a few decades. Some molecular approaches, such as antisense, oligonucleotides, ribozymes, RNA interference targeting HBV mRNA, are available in antiviral therapies.

DKK 514.00
1

In Situ Uranium Stabilization Through Polyphosphate Remediation - M D Williams - Bog - Nova Science Publishers Inc - Plusbog.dk

In Situ Uranium Stabilization Through Polyphosphate Remediation - M D Williams - Bog - Nova Science Publishers Inc - Plusbog.dk

The Hanford Site, in south-eastern Washington State, is a former nuclear defence production facility. A groundwater plume containing uranium, originating from a combination of purposeful discharges of wastewater to cribs, trenches, and ponds, along with some accidental leaks and spills with nuclear fuel fabrication activities, has persisted beneath the Hanford Site 300 Area for many years. The uranium plume is just upstream of the city of Richland municipal water supply intake on the Columbia River. Despite the cessation of uranium releases and the removal of shallow vadose zone source materials, the remedial action objective to lower the concentration of groundwater uranium to the U.S. Environmental Protection Agency (EPA) maximum contaminant level (MCL) concentration of 30 µg/L has not been achieved within the anticipated 10-year time period. Despite several decades of studies, effective uranium cleanup strategies remain elusive for contamination in deep subsurface settings that prevail at a number of U.S. Department of Energy (DOE) sites in the western United States. Numerous strategies have been proposed including iron barriers, soluble reductive agents, microbial stabilisation via reduction and precipitation, and emplacement of solid phosphate barriers. While these all have merit, each encounters limitations for deep subsurface remediation in an oxidative environment (Peterson et al. 2005; Wellman et al. 2005b; Wellman et al. 2006c; McGrail and Mattigod 1999; DOE 2005a; DOE. 2005b). Polyphosphate technology has been demonstrated to delay the precipitation of phosphate phases for controlled in situ formation of stabile phosphate phases which control the long-term fate of uranium (Wellman et al. 2005b; Wellman et al. 2006c). Precipitation of phosphate minerals occurs when phosphate compounds degrade in water to yield the orthophosphate molecule (PO43 ). Accordingly, a detailed understanding of polyphosphate degradation and reaction kinetics, in the context of site-specific information, allows the technology to be tailored as a time-released source of phosphate for direct subsurface treatment without a drastic change in hydraulic conductivity of the target aquifer. A site-specific treatability test was conducted to optimise polyphosphate remediation technology for implementation through a pilot-scale field technology demonstration to accelerate monitored natural attenuation of the uranium plume within the Hanford 300 Area aquifer. A focused application of polyphosphate was conducted in a source or "hot spot" area to reduce the inventory of available uranium that contributes to the groundwater plume through direct precipitation of uranyl-phosphate solids and secondary containment via precipitation of apatite acting as a long-term sorbent for uranium. The general treatability testing approach consisted of initial site characterisation and set-up, a polyphosphate injection test, and post-treatment performance assessment. Fundamental science studies were conducted with site- specific sediment and groundwater to develop an effective remediation scheme for deployment of polyphosphate technology. In addition to remediating a portion of the plume, the data from this test provide valuable information for designing a full-scale remediation of uranium in the aquifer at the 300 Area of the Hanford Site. Results provide a detailed understanding of the fundamental underpinnings necessary to evaluate the efficacy and potential use of polyphosphate technology at other sites with varying geochemical and hydrodynamic conditions.

DKK 405.00
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Recent Trends in Understanding and Tackling Gram-Negative Infections - - Bog - Nova Science Publishers Inc - Plusbog.dk

Recent Trends in Understanding and Tackling Gram-Negative Infections - - Bog - Nova Science Publishers Inc - Plusbog.dk

Antibiotics have vastly changed the way we fight diseases. History is replete with examples of infectious diseases that have killed millions of people worldwide in the past and continues to do so in the present. However, there is one major difference. In the past there were novel classes of antibiotics that were being discovered at regular intervals, and in the present we are running out of options. Moreover, whatever antibiotics we have, microbes have developed resistance, which could primarily be attributed to the injudicious usage of antibiotics, not only for humans but also for veterinary purposes. A previous report from World Health Organization (WHO, 2017) suggests that antimicrobial resistance is a serious hazard and antibiotics under clinical development may not be sufficient (or efficient enough) to treat these emerging resistant pathogens. That report had identified 51 antibiotics and 11 biologicals. Of those, only 12 were found to be active against WHO classified critical priority pathogens and only two of them were found to be active against more than one specific pathogen. Starting with the sulphonamides in the 1930s to lipopeptides in the early 2000s, research and development on novel antibiotics is usually a slow and painful process and currently it will suffice to say that it is on the decline. As per the Infectious Diseases Society of America (IDSA), we are facing what is known as an antibiotic paradox that is pushing against the development of novel antibiotics. Interestingly, though there are studies that keep reporting on antibiotics, most of these are on combinatorial use of antibiotics. What could be their effectiveness and more importantly what could be their biotoxicity in the long run, remains unknown. Microbial antibiotic resistance is not a new phenomenon and there are numerous studies that have demonstrated the various mechanisms underlying it. An interesting study by Indian Council of Medical Research (ICMR), has shown that commensals in the gastrointestinal tract of humans might be responsible for the increasing ineffectiveness of antibiotics, at least in Indians. This makes it clear that microbes will keep on producing resistance to antibiotics at a faster rate compared to our ability to develop them. Under these circumstances, natural compounds, primarily plant-based, have become valuable tools and could be our answer to not only effective antimicrobial principles, but also to antimicrobial resistance. These compounds are abundant in nature and there is already a very rich literature on their usage and efficacy based on the various traditional systems of medicine. These natural compounds have been shown to be effective against both Gram positive and Gram-negative pathogens and interestingly microbes have a limited chance (as far as studies show) of developing resistance towards them. This is primarily attributed to the fact that most of these compounds are used as polyherbal formulations. Another advantage in studying these natural compounds is that there is a better probability of hitting upon that jackpot molecule or molecules for antimicrobial applications. Being relatively safe and inexpensive makes them very attractive areas for clinical research. This book, in line with others in the field, is a small attempt to highlight the developments related to the antimicrobial compounds from natural sources and their mechanisms of action, particularly against ESKAPE pathogens. This book, we believe, will serve as a small but important piece of source material for students and researchers interested in this particular area of research. The chapters are divided to showcase the relevance and importance of natural compounds as novel antimicrobials, inhibitors of antimicrobial resistance and immunomodulators and we hope that the topics will kindle the interest of young researchers in these lines. In the end, we are grateful and whole heartedly acknowledge the authors for their valuable contribution and reviewers for their valuable suggestions and critical review of the manuscripts.

DKK 718.00
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