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X-Ray Optics & Inner-Shell Electronics of Hexagonal BN - Andrey A Pavlychev - Bog - Nova Science Publishers Inc - Plusbog.dk

X-Ray Optics & Inner-Shell Electronics of Hexagonal BN - Andrey A Pavlychev - Bog - Nova Science Publishers Inc - Plusbog.dk

In This book, special emphasis is placed on the interaction of X-ray polarised and non-polarised radiation with hexagonal BN (h-BN) crystal. h-BN is one of the most anisotropic layer compounds. Near the B and N K shell ionisation thresholds the dielectric tensor in h-BN demonstrates sharp variations with photon energy and results in intriguing optical properties of the compound. X-ray absorption near the thresholds is strongly influenced by the short range order parameters of the layers and demonstrates the pronounced "molecular" properties.

DKK 534.00
1

Protest & Issues Around the Air Force Refueling Tanker - - Bog - Nova Science Publishers Inc - Plusbog.dk

Protest & Issues Around the Air Force Refueling Tanker - - Bog - Nova Science Publishers Inc - Plusbog.dk

KC-X is the first of three planned programs intended to recapitalise the Air Force''s air refuelling fleet. Eventually, the KC-X program is expected to acquire 179 new, commercial off-the-shelf airliners modified to accomplish air refuelling. The program is expected to cost $35 billion. Both Boeing and a consortium consisting of Northrop Grumman and European Aeronautic Deference and Space Company (EADS) competed for KC-X. Boeing offered a variant of the 767-200, while Northrop Grumman submitted a version of the Airbus 330-200. On February 29, 2008, the Air Force awards the KC-X contract to Northrop Grumman. The initial $12.1 billion KC-X contract covers purchase the first 68 KC-45s of the anticipated 179 aircraft. Boeing protested the Air Force''s decision to the Government Accountability Office (GAO). GAO upheld the Boeing protest, and in July, Defense Secretary Robert Gates announced that he would reopen the tanker competition. This book explains the protests and issues surrounding the Air Force refuelling tanker competition. This book consists of public documents which have been located, gathered, combined, reformatted, and enhanced with a subject index, selectively edited and bound to provide easy access.

DKK 633.00
1

Chitosan-Based Hydrogels for Tissue Engineering Applications - G Luna Barcenas - Bog - Nova Science Publishers Inc - Plusbog.dk

Chitosan-Based Hydrogels for Tissue Engineering Applications - G Luna Barcenas - Bog - Nova Science Publishers Inc - Plusbog.dk

The polyelectrolyte complexes formed due to electrostatic attraction between the polymers, have improved properties when compared to hybrid CTS-g-GMA, which provides a wide range of applications in the biomedical field. All materials have been characterised by different analytical techniques such as infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermal analysis (DSC and TGA), and the results were compared to the precursor materials (chitosan, X, HA, and CTS-g-GMA). Due to the HA nature, the film obtained from this reaction has been assessed for use as a patch for wound healing; whereas the properties showed by the hydrogels obtained from the reaction with X, make them very promising for applications in the treatment of recovery of spinal cord injuries. This book presents results which strongly support the future use of hydrogels as scaffolds for tissue engineering and recovering.

DKK 534.00
1

Electrochemical Impedance Spectroscopy - - Bog - Nova Science Publishers Inc - Plusbog.dk

Electrochemical Impedance Spectroscopy - - Bog - Nova Science Publishers Inc - Plusbog.dk

In Chapter One, the authors review the recent developments in the field of electrochemical impedance spectroscopy, discuss some of the challenges and compare EIS with the other relevant techniques. The effect of storage time without use (STWU) in the supporting electrolyte solution on the conducting properties of poly(o-aminophenol) (POAP) film electrodes was studied in Chapter Two. In Chapter Three, the authors study the effect of the cerium content on the corrosion behavior of Al85CexNi15-x (x = 4, 5, 6, 7 and 10) amorphous alloys obtained by melt spinning.

DKK 1034.00
1

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

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

Crystal structures and their associated electronic features play an enormous role in chemistry, constituting the most fundamental basis for analyzing and predicting properties of solid-state materials. In Crystal Structure: Properties, Characterization and Determination, the authors begin by discussing some of the refining models and X-ray data treatments for single-crystals containing heavy atoms, such as transition metals or lanthanides.Valuable information on crystal structures and microstructures may be obtained from the observation of high-resolution images if conditions associated iwth crystal thickness and defocus values are satisfied. These images include information not only on accurate atomic coordinates of cations but also on the ordered arrangements of oxygen atoms and oxygen vacancies.In the concluding study, measurements of the heat capacity of Y3-xErxAl5O12 (x=0,0.6,1.1,3), and mixed Er3-xTmx Al5O12, (x=0,1,2,3) and Er2HoAl5O12 solid solutions were carried out in the temperature range of 1.9 to 220 K in magnetic fields up to 9T. The findings suggest that heat capacity variations at low temperatures were impacted by Schottky anomalies.

DKK 820.00
1

P-Type Transparent Semiconducting Delafossite CuA102+x Thin Film - Kalyan K Chattopadhyay - Bog - Nova Science Publishers Inc - Plusbog.dk

P-Type Transparent Semiconducting Delafossite CuA102+x Thin Film - Kalyan K Chattopadhyay - Bog - Nova Science Publishers Inc - Plusbog.dk

Copper based delafossite transparent semiconducting oxide thin films have recently gained tremendous interest in the field of optoelectronic technology, after the discovery of p-type conductivity in a transparent thin film of copper aluminium oxide (CuAlO2). Most of the well-known and widely used transparent conducting oxide thin films such as ZnO, SnO2, ITO etc. and their doped versions are n-type material, but corresponding p-type transparent conducting oxides were surprisingly missing for a long time until the fabrication of above-mentioned p-CuAlO2 thin film have been published (Nature 1997, 389, 939). This has opened up a new field in opto-electronics device technology, the so-called "Transparent Electronics", where a combination of the two types of transparent conducting oxides in the form of a p-n junction could lead to a ''functional'' window, which transmits visible portion of solar radiation yet generates electricity by the absorption of UV part of it. Non-stoichiometric and doped versions of various new types of p-type transparent conducting oxides with improved optical and electrical properties have been synthesised in the last few years in this direction. Wide range of deposition techniques have been adopted to prepare the films. But fabrication of device quality films by cost-effective deposition techniques such as sputtering, chemical vapour deposition, wet-chemical dip-coating technique etc. are the need of the hour for large-scale production of these films for diverse device applications. Here the authors have discussed the fabrication and opto-electrical characterisation of p-CuAlO2+x thin films by cost-effective and scalable deposition routes such as sputtering and wet-chemical dip-coating technique. The authors have also discussed briefly some of the new developments in the field of p-type transparent conducting oxide thin film technology and an up-to-date and comprehensive description of different Cu-based p-type transparent conducting oxide thin films is presented. Also the origin of p-type conductivity in these transparent oxides has been dealt with considerable attention. Fabrication of all-transparent junctions is also discussed which is most important in the development of ''Transparent Electronics''. Field emission properties of thin films are currently of much interest due to the potential application in field emission displays (FEDs), which are considered to be strong candidate for low-power panel applications. The low-threshold field emission properties of wide-bandgap CuAlO2 thin films have been investigated for its potential applications in FED technology. The films showed considerable low turn-on field. This finding might open up a new direction in the field-emission technology, and a new group of materials (such as, different transparent conducting oxides) might become a promising candidate for low-threshold field emitter. Also, recently, the research on nanostructured materials generates great interest in the scientific community and offers tremendous opportunities in the field of science and technology. Here, the authors have also discussed in brief, the formation of nanocrystalline p-CuAlO2 films, which may open up an extremely important and interesting field of research for the fabrication of all-transparent nano-active devices. This will not only give a new dimension in the field of ''Transparent Electronics'', but new avenues may open up in the nanoparticle research keeping an eye on its tremendous applications in optoelectronics technology.

DKK 534.00
1

Digital Tomosynthesis - - Bog - Nova Science Publishers Inc - Plusbog.dk

Digital Tomosynthesis - - Bog - Nova Science Publishers Inc - Plusbog.dk

Tomosynthesis is a technology that enables the acquisition of three-dimensional (3D) data from a sequence of projection images acquired at different x-ray tube angles. Tomosynthesis imaging is being actively investigated for use in a variety of clinical tasks. Chapter One of this book provides a comparison of reconstruction algorithms in terms of radiation dose reduction of x-ray tomosynthesis. Digital Breast Tomosynthesis (DBT), an emerging and improving breast imaging technology, enhances the diagnosis of early breast cancer by providing in-depth information about the overlapping dense breast tissues with no ambiguities. Chapter Two reviews population-based screening/clinical trials of digital breast tomosynthesis. The last chapter discusses image reconstruction and imaging configuration optimization with a multi-beam parallel digital breast tomosynthesis system.

DKK 820.00
1

Polycrystalline Films - - Bog - Nova Science Publishers Inc - Plusbog.dk

Polycrystalline Films - - Bog - Nova Science Publishers Inc - Plusbog.dk

This book provides new research on polycrystalline films. Chapter One reviews the characterisation of polycrystalline Cu2ZnSn(SxSe1-x)4 thin-films and solar-cells. Chapter Two explains the chemical vapor deposition process accelerated by the fragments of monomethylsilane. Chapter Three studies the regularities of formation of the nanostructured films of polycrystalline silicon doped with germanium as isovalent impurity.

DKK 1034.00
1

Trace Metals - - Bog - Nova Science Publishers Inc - Plusbog.dk

Trace Metals - - Bog - Nova Science Publishers Inc - Plusbog.dk

Many types of urban soils, including tree pit soil, contain elevated concentrations of trace metals as compared to agricultural and natural soils. Chapter One describes how trace metals from vehicular emissions and the degradation of urban infrastructure are carried by runoff into the soil of green infrastructure such as tree pits and grassed boulevards. Chapter Two compiled As concentration data from water wells, sediments, and soils in Araihazar that were collected from the public sources and government agencies. Chapter Three focuses on the investigation of the distribution of Fe plaque in the root epidermis of selected wetland plant species (Phragmites australis, Typha latifolia and Spartina alterniflora) using synchrotron X-ray microfluoresces, X-ray absorption near edge structure and transmission X-ray microscope techniques with (sub)micro-scale resolution. Chapter Four investigates the possibility of temporal and spatial variations of potential ecological risk assessments (PERI) of Cd, Cu, Hg, Pb and Zn in the surface sediments based on four sampling cruises in the Straits of Malacca. Characterization of metals in sediments from the New York/New Jersey Harbor is necessary as part of the basic information needed in work related to dredging and environmental effects and restoration efforts in the region as reported in Chapter Five. Chapter Six discusses the arsenic concentrations in the groundwater of the lowlands of Nepal (the so called Terai).

DKK 1034.00
1

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

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

In the opening attempts are made to provide a brief survey of di-imines derived from benzil hydrazones through imine chemistry. Imines are compounds containing an azomethine linkage C=N connected to hydrogen or carbon atoms. Possible reaction mechanisms of benzocyclonhexanone oximes and p-quinone monoimines with Lawesson''s and tris(dimethylamino)phosphine reagents are considered in chapter two, and the structural assignments are based on spectroscopic data and x-ray analysis. Three catalogues of imine gels are discussed in the penultimate chapter, namely gels of discrete imine molecules, gels of imine polymers assembled from small molecular precursors and gels of imine polymers assembled from polymer precursors. The structure of penicillin was determined by X-ray in 1945, and the first total synthesis was then reported by Sheehan and Henery-Logan. A brief history of the structure of penicillin is presented in the final chapter, with emphasis on recent progress.

DKK 718.00
1

Two-Dimensional Periodic Nanoscale Patterning of Solid Surfaces by Four-Beam Standing Wave Excimer Laser Lithography - D O Filatov - Bog - Nova

Two-Dimensional Periodic Nanoscale Patterning of Solid Surfaces by Four-Beam Standing Wave Excimer Laser Lithography - D O Filatov - Bog - Nova

This book presents and discusses a promising technology for fabrication of the one- and two-dimensional nanoperiodic structures on the solid surfaces by direct two- and four-beam standing wave pulsed laser modification. This method being developed extensively at present is very promising for application in nanoelectronics, data storage, integrated optics, and is considered to be a promising alternative to X-ray lithography in a wide range of applications.

DKK 633.00
1

A Classical Description of Variational Quantum Mechanics and Related Models - Fabio Silva Botelho - Bog - Nova Science Publishers Inc - Plusbog.dk

A Classical Description of Variational Quantum Mechanics and Related Models - Fabio Silva Botelho - Bog - Nova Science Publishers Inc - Plusbog.dk

In this text, the author establishes a connection between classical and quantum mechanics through the normal field definition and related wave function concept. Indeed, the author proposes a new energy which includes both classical and quantum mechanics in a unified framework. Concerning such energy, they show that if ℏ≪m, where m denotes the total system mass, then the energy is experienced in a classical mechanics context, whereas if the approximation r(x,t)≈x is assumed, where r(x,t) denotes point-wise the particle classical field of position, and for appropriate m values the standard Schrödinger energies are re-obtained. Among the examples of applications concerning the proposal, the author highlights the hydrogen atom as one example, where both the proton and electron are allowed to move. The consistent result of a proton mass concentration at r = 0 is obtained. The author also develops a procedure to obtain eigenvalues of a positive definite symmetric matrix. The novelty here, concerning previous results in the book entitled Functional Analysis and Applied Optimization in Banach Spaces, are the rigorous proofs presented. Indeed, the results seem to be applicable to more general matrices. However, the author postpones the proof of such general results for future research. In the last chapter, a complete and rigorous existence result for the Ginzburg-Landau system of superconductivity is presented. A duality principle and related optimality conditions are also developed. In the final section, the author presents research concerning numerical results for three-dimensional models in superconductivity.

DKK 820.00
1

Heating Systems - - Bog - Nova Science Publishers Inc - Plusbog.dk

Heating Systems - - Bog - Nova Science Publishers Inc - Plusbog.dk

This book first discusses the development of different types of district heating systems, highlighting the main features of low temperature district heating and discussing its potential for supplying decarbonised heat. As buildings consume about 40% of the world's annual energy consumption globally, the authors focus on the evaluation of residential heating system alternatives using fuzzy numbers. Multi-criteria decision making techniques, fuzzy AHP and fuzzy ANP methods are used for evaluation and the results of both algorithms are compared. Research is presented which is aimed at designing a logistics system for X Gas Company to ensure efficient distribution of liquefied petroleum gas, which begins with the ordering process and ends with the placement of stations in Istanbul-Turkey, taking into account the storage, preparation, loading and delivery operations of X Gas Company. In closing, three types of electro heating skin-systems are presented and the main features of skin heating systems are considered. The advantages of these systems for heating extra-long pipelines transporting oil, gas, water and other liquids are explored.

DKK 624.00
1

ZnO Nanostructures - - Bog - Nova Science Publishers Inc - Plusbog.dk

ZnO Nanostructures - - Bog - Nova Science Publishers Inc - Plusbog.dk

Different ZnO nanostructures are attributed to different electronic properties which are favourable in the application of photocatalysis, sensing and energy harvesting. The non toxic behaviour of ZnO nanostructures lead to the use of this material in environmental sensing and environmental remediation. In ZnO Nanostructures: Advances in Research and Applications, a large-scale synthesis of undoped low-dimensional semiconductor metal oxide nanostructures is performed by simple wet-chemical method using reducing agents at low temperature. The detailed structural, compositional, and optical characterizations of the ZnO nanoparticles were evaluated by powder X-ray diffraction pattern, Fourier-transform infra-red spectroscopy, X-ray photoelectron spectroscopy, electron dispersion spectroscopy and UV-vis. Spectroscopy. Following this, the authors describe the structure electrochemical sensors, listing scientific papers focusing on the detection of different pathogens and analytes, as well as reporting and comparing the performance of the sensors prepared by various groups around the world. The concluding chapter deals with synthesis protocols of ZnO heterostructures along with their role in optoelectronic applications. Their thermodynamic stability and correlation among morphology, defects, and heterostructure with luminating and catalytic properties is also described.

DKK 890.00
1

Cancer Treatment - - Bog - Nova Science Publishers Inc - Plusbog.dk

Cancer Treatment - - Bog - Nova Science Publishers Inc - Plusbog.dk

Chemotherapy is a type of cancer treatment that uses drugs to destroy cancer cells. Chemotherapy works by stopping or slowing the growth of cancer cells, which grow and divide quickly. But it can also harm healthy cells that divide quickly, such as those that line your mouth and intestines or cause your hair to grow. Damage to healthy cells may cause side effects. Often, side effects get better or go away after chemotherapy is over. This book focuses on how patients undergoing chemotherapy can manage their side effects, which symptoms to watch out for, and how to communicate effectively with their health care team. Radiation therapy (also called radiotherapy) is a cancer treatment that uses high doses of radiation to kill cancer cells and stop them from spreading. At low doses, radiation is used as an x-ray to see inside your body and take pictures, such as x-rays of your teeth or broken bones. Radiation used in cancer treatment works in much the same way, except that it is given at higher doses. This book provides facts about radiation therapy and side effects and describes how patients can care for themselves during and after treatment.

DKK 890.00
1

Medicaid Fee-For-Service Payments - - Bog - Nova Science Publishers Inc - Plusbog.dk

Medicaid Fee-For-Service Payments - - Bog - Nova Science Publishers Inc - Plusbog.dk

On 22 November 2003, the House of Representatives voted 220 to 215 to approve the conference report on H.R. 1, the Medicare Prescription Drug, Improvement, and Modernisation Act of 2003. The Senate, on November 24th, voted 54 to 44 to approve the conference report. The bill was signed by the President in a ceremony on December 8th. The legislation adds a prescription drug benefit to Medicare and replaces the existing Medicare+Choice program with a new Medicare Advantage program that establishes managed care payments based on a system of bids and benchmarks. The bill also contains numerous provisions that would generally increase fee-for-service payments within Medicare''s Part A and Part B program (also known as traditional Medicare), especially for rural health care providers; numerous regulatory and administrative practices will also be modified. This book discusses the fee-for-service (FFS) provisions of the legislation, those affecting Medicaid as well as the Medicare cost containment provisions. It compares the provisions in the bill as enacted with those in the Medicare reform bills that were originally passed by the Senate and the House. The Medicare FFS provisions in the bill are found primarily in Titles GGIII through VIII; some FFS provisions are included in Titles VIII through X as noted. The cost containment provisions are in Title VIII and the Medicaid and other provisions are in Title X.

DKK 316.00
1

Forensic Medicine - - Bog - Nova Science Publishers Inc - Plusbog.dk

Forensic Medicine - - Bog - Nova Science Publishers Inc - Plusbog.dk

This book provides current research on the fundamentals, clinical perspectives and challenges of forensic medicine. Chapter One reviews recent literature about the technologies that can be used to predict Externally Visible Characteristics through Forensic DNA Phenotyping (FDP). Chapter Two examines energy dispersive X-ray fluorescent spectrometry (EDX) for multi-element analysis. Chapter Three reviews the legal doctrine of informed consent in Italy. Chapter Four describes the Italian situation about the evaluation of dental damage, focusing attention on the renewals of treatment and the cases worthy of compensation. An original position about the quantification of permanent biological damage of the teeth used as prosthetic abutments is also presented.

DKK 1034.00
1

Chest Pain - - Bog - Nova Science Publishers Inc - Plusbog.dk

Chest Pain - - Bog - Nova Science Publishers Inc - Plusbog.dk

Chest pain may be a symptom of a number of serious conditions and is generally considered a medical emergency. Even though it may be determined that the pain is non-cardiac in origin, this is often a diagnosis of exclusion made after ruling out more serious causes of the pain. This book gathers and presents topical data on the causes, diagnosis and treatment of chest pain including integrated studies of western and traditional Chinese medicine on Cardiac Syndrome X with chest pain, angina and chest pain, a look at the available prediction instruments that can be used for the classification of acute coronary syndrome (ACS), and ambient nitrogen dioxide and female emergency room visits for chest pain.

DKK 718.00
1

Internet Television Streaming, Copyright Law & the Aereo Supreme Court Decision - - Bog - Nova Science Publishers Inc - Plusbog.dk

Internet Television Streaming, Copyright Law & the Aereo Supreme Court Decision - - Bog - Nova Science Publishers Inc - Plusbog.dk

Aereo and FilmOn X stream television programming over the Internet for a monthly subscription fee. Aereo and FilmOn''s technology permits subscribers to watch both live broadcast television in addition to already-aired programming. Their use of this development in technology has triggered multiple lawsuits from broadcasting companies alleging copyright violations. These cases reveal not only multiple interpretations of copyright law and its application to new and developing technologies but also a possible "loophole" in the law, which some have accused Aereo and FilmOn of exploiting. This book discusses internet television streaming and copyright laws. It then discusses remote-storage digital video recorders and the copyright laws that go along with it.

DKK 890.00
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

Contention-Based Collision-Resolution Medium Access Control Algorithms - Jesus Alonso Zarate - Bog - Nova Science Publishers Inc - Plusbog.dk

Contention-Based Collision-Resolution Medium Access Control Algorithms - Jesus Alonso Zarate - Bog - Nova Science Publishers Inc - Plusbog.dk

This book is an overview of the most relevant collision resolution algorithms used in contention-based multiple access protocols to handle collisions among users contending for channel access. The two main categories of collision resolution algorithms are the so called back-off and the splitting algorithms. The described back-off algorithms are further classified into p-persistent, binary exponential, X-Increase Y-Decrease and dynamic optimum back-off window algorithms. On the other hand, the splitting algorithms are basically characterised as gated-access, window-access and free-access. The dynamic tree algorithm and some limited sensing algorithms are also discussed. Other proposals that cannot be classified in the previous categories are also presented. Finally, examples of MAC protocols for wireless communications that make use of some of the aforementioned collision resolution algorithms are included.

DKK 405.00
1

Foldases Catalyzing the Formation & Isomerization of Disulfide Bonds in Proteins - Natalya K Nagradova - Bog - Nova Science Publishers Inc -

Foldases Catalyzing the Formation & Isomerization of Disulfide Bonds in Proteins - Natalya K Nagradova - Bog - Nova Science Publishers Inc -

One of the rate-limiting steps in the folding pathways of many secretory proteins is the formation of correct disulfide bonds between cysteine residues. In eukaryotes, both disulfide bond formation and isomerisation which shuffles incorrectly formed disulfides are catalysed by protein disulfide isomerase (PDI), whereas in bacteria these two reactions are catalysed by separate enzymes. Both in eukaryotic and prokaryotic cells the oxidation and isomerisation steps proceed exclusively in extracytoplasmic environments (the lumen of the eukaryotic endoplasmic reticulum and the Gram-negative bacterial periplasmic space). The family of foldases under discussion is characterised by a conserved "thioredoxin fold" and a common active site motif: Cys-X-X-Cys. The process of disulfide bond formation relies on thiol-disulfide exchange between oxidised and reduced cysteine pairs in the catalyst and substrate protein. Two separate pathways involved in disulfide bond formation and isomerisation have been characterised both in eukaryotes and in bacteria. In the oxidative pathway, oxidizing equivalents flow from oxygen to a membrane protein (Ero1p in eukaryotes or DsbB in bacteria), and then to a folding protein containing reduced cysteines via PDI (in eukaryotes) or via DsbA (in bacteria). In the isomerisation pathway, DsbC (bacterial protein disulfide isomerase) or PDI (in eukaryotes) interacts with substrate proteins that contain non-native disulfide bonds, allowing these bonds to rearrange to their native pairings. Reducing equivalents which are necessary to maintain DsbC in a reduced form, able to attack misfolded disulfides, are transferred from the cytoplasm with the aid of the cytoplasmic membrane protein DsbD. In eukaryotes, reduced glutathione is the main source of reducing equivalents for PDI. A dual role of PDI as an oxidase and an isomerase is facilitated by its complex domain architecture.

DKK 405.00
1

Porous Structure & Adsorption Behaviours of Chitosan - N V Serebryakova - Bog - Nova Science Publishers Inc - Plusbog.dk

Porous Structure & Adsorption Behaviours of Chitosan - N V Serebryakova - Bog - Nova Science Publishers Inc - Plusbog.dk

This book reviews the interrelation between the structure and adsorption properties of water and nitrogen vapours and Ni, Cu and Ag cations of the chitosan samples modified by freeze-drying after precipitation with NaOH or Na2CO3 or drying in air, as well as cross-linking. The investigations by IR spectroscopy, X-ray diffraction and pulsed NMR show the influence of the preliminary treatments on the Supramolecular structure. The more ordered structure is observed in the freeze-dried samples of chitosan compared with the air-dried sample. The parameters of the porous structure of the chitosan samples calculated from the isotherms of water vapours adsorption and the nitrogen vapours low temperature adsorption are compared. It is revealed that the isotherms of water vapours adsorption on the chitosan samples are more sensitive to the structural modification of polymers.

DKK 534.00
1

Silicon-Based Inorganic Polymers - - Bog - Nova Science Publishers Inc - Plusbog.dk

Silicon-Based Inorganic Polymers - - Bog - Nova Science Publishers Inc - Plusbog.dk

Inorganic polymers are large molecules, usually linear or branched chains with atoms other than carbon in their backbone. In this new advanced research book, silicon-based inorganic polymers are treated by J Cypryk (Poland), G. Kickelbick (Austria), X. Coqueret (France), A. Colas (Belgium), J. Koe (Japan), W. Uhlig (Switzerland), and by M. Rehahn and M. Weinmann (Germany). Different aspects of phosphorus-containing macromolecules are described by F.F. Stewart (USA), R. De Jaeger and L. Montagne (France), and by M. Carenza, S. Lora, and M.Gleria (Italy). Tin- and germanium-based polymers are illustrated by M. Okano (Japan), while inorganic dendrimers are presented by A.M. Caminade and J.P. Majoral (France) and by V. Balzani (Italy). Miscellaneous topics covering the flame-retardant and the intumescent behavior of the inorganic macromolecules (S. Bourbigot, France), ionically-conductive inorganic macromolecules (E. Montoneri, Italy) and chiral inorganic polymers (G.A. Carriedo and J.F. Garcia-Alonso, Spain) are also addressed.

DKK 890.00
1