bluuebunny/crossref_metadata_2025 huggingface dataset:
A Short Stem Solution: Through Small Portals
Authors: Lombardi Adolph V. , Berend Keith R. , Adams Joanne B.
Published: September 2009

While short stem design in total hip arthroplasty (THA) is not a new concept, interest has surged with the increasing popularity of less invasive techniques. Given the success of traditional stems, why consider short stems? Several reasons exist. If the goal of the tapered stem is to load preferentially proximally, achieve tight fit, and deliver stresses into proximal bone, do we need a stem at all? While long stems may prevent varus malalignment, varus malalignment of tapers does not impair results. Short stems are easier to insert, especially when using an anterior approach. Femoral preparation is accomplished with straightforward broaching without reamers. Short stems are bone conserving, violating less bone stock and providing more favorable conditions should revision be required. As with any novel device, longer follow-up is needed to fully assess shortened tapered stems. However, our early results in 640 primary THAs at up to 38 months are promising.

Usually 1 or 2 diameter sizes larger are required with the short vs standard length version of the same tapered design. Be aggressive with sizing, pushing to the largest possible. Use the broach like a rasp. Drive the component in valgus during insertion. Upon seating, do a trial reduction using the shortest available neck length. The component generally sits slightly prouder than the broach and may require additional effort to seat completely.
Total Hip Arthroplasty in Acetabular Protrusio
Authors: Ries Michael D.
Published: September 2009

Protrusio is a central acetabular defect resulting from migration of the femoral head medial to Kohler's line. Protrusio can develop in association with a number of conditions that affect the metabolism or mechanical behavior of the periacetabular bone. Total hip arthroplasty (THA) for acetabular protrusio requires reconstruction of the contained cavitary defect. The acetabular rim is generally intact. The defect can be effectively treated with a lateralized cementless porous-coated component supported on the peripheral acetabular bony rim. Morsellized autograft is used to fill the medial defect. However, if the rim is inadequate to provide mechanical support for a cementless cup due to bone loss or osteoporosis, cementless cup reconstruction can result in medial migration. If rim support is inadequate, a reconstruction cage is a more appropriate option to gain fixation to the pelvis above and below the acetabulum. Total hip arthroplasty for protrusio can also affect both offset and leg length, so careful preoperative templating is important to help determine implant position. Results of THA with medial acetabular bone grafting for protrusio acetabuli have been favorable, with success rates similar to conventional THA.
The Dislocator, Early and Late: The Role of Large Heads
Authors: Skeels Michael D. , Berend Keith R. , Lombardi Adolph V.
Published: September 2009

Dislocation after total hip arthroplasty (THA) is a potentially devastating complication that can be difficult to manage. Many patient and mechanical factors have been associated with an increased risk of dislocation. Conservative treatments such as abduction bracing have not proven effective at treating this difficult problem. Surgical options include the use of larger femoral heads, unconstrained tripolar femoral heads, and constrained devices. While each device has its merits, there is no one-size-fits-all solution to this problem. With the development of highly cross-linked polyethylene and its superior wear characteristics and mechanical properties, the use of larger femoral heads is now available.

Twenty-six hips in 25 patients who underwent revision surgery for recurrent dislocation were treated with a femoral head ⩾36 mm in diameter. The direct lateral surgical approach was used in 24 hips, and the posterior and anterior supine intermuscular approaches were used in 1 hip each. One patient died 5 years after revision surgery, and 3 patients have not returned for clinical follow-up over the past 2 years. Four hips subsequently suffered a repeat dislocation, for a dislocation rate of 17%. Two patients underwent a subsequent surgery: 1 irrigation and debridement and 1 hardware removal. There have been no other revisions to date. Mean time to follow-up is 17.2 months. While the use of large femoral heads for the treatment of dislocation is warranted, continued follow-up is necessary.
Extra-articular Deformity is Always Correctable Intra-articularly: To the Contrary
Authors: Hungerford David S.
Published: September 2009

The operative word in this debate is “always.” In my opinion, there are some cases better served by extra-articular correction. The question then becomes which ones, and how does the surgeon determine? There are 4 considerations: the magnitude of the deformity, the relationship of the deformity to the knee, the side of the deformity (varus or valgus), and whether the femur or the tibia is affected by the deformity. A larger deformity is more important, but just as important is its relationship to the knee. Large deformities distant to the knee have little impact on the knee. Varus deformities require lateral intra-articular overresection, which produces lateral instability. Valgus deformities require medial overresection, which produces medial instability. Lateral instability is stabilized by the dynamic lateral stabilizers (popliteus, lateral head of the gastrocnemius, biceps femoris, and iliotibial tract) and is better tolerated than medial instability. The best way to determine the consequence of the malalignment in question is to template the knee by drawing the mechanical axis from the femoral head or ankle to the center of the knee, and then the resection level that will be required. This will demonstrate the amount of overresection required to correct the extra-articular deformity, and in some cases will indicate the advantage of an extra-articular correction.
Malalignment: Forewarned is Forearmed
Authors: Fang David , Ritter Merrill A.
Published: September 2009

Malalignment in total knee arthroplasty (TKA) is a major source of failure. Concern exists as to the acceptable window for overall coronal alignment in TKA. We evaluated the anatomical coronal alignment of 6070 primary TKAs using standard-length knee radiographs. The mean postoperative alignment was 4.8° of valgus, with 1 standard deviation within the mean defining a range of 2.4° to 7.2° of valgus. The revision rate not related to infection for this well-aligned group was 0.5% (3°=0.47%; 4°=0.54%; 5°=0.47%; 6°=0.39%; 7°=0.62%). In comparison, the failure rate for TKAs aligned in relative varus (<2.4° of valgus) was 1.8% (
P
=.0004) and for those in valgus (>7.2° of valgus) was 1.5% (
P
=.0027). Kaplan-Meier survival analysis confirmed these findings. The failure rates were statistically higher for the valgus and varus groups, compared to the well-aligned group within 1 standard deviation of the mean. Moreover, varusaligned knees failed primarily by medial tibial collapse, whereas valgus-aligned knees failed because of ligamentous laxity. Restoring coronal alignment to between 2.4° and 7.2° of anatomical valgus is the most important surgeon-controlled factor in TKA.
Salmonella
Osteomyelitis in New-onset Diabetes Mellitus
Authors: Gondusky Joseph S. , Gondusky Christina J. , Helmers Scott W.
Published: September 2009

Salmonella
species are rare bacterial isolates in osteomyelitis. This article describes a case of an otherwise healthy, active duty male military member with an insidious onset of right knee pain during a deployment to Kuwait. His work-up revealed an infectious process in the distal femur. Operative treatment and intravenous antibiotics resolved the infection. Intraoperative cultures revealed the rare isolate
Salmonella enterica
serotype C2 (Newport). Postoperative medical management revealed new-onset diabetes mellitus, possibly making this otherwise healthy host susceptible to this rare infection.

Salmonella
are gram-negative bacteria. Infection with nontyphoidal
Salmonella
species most commonly manifests as intestinal illness. Although it may be difficult for clinicians to accurately predict this rare entity as the causative organism in osteomyelitis, they may be aided by a history of travel to endemic regions or exposure to animal carriers. Comorbidities that seem to increase susceptibility include diabetes mellitus, human immunodeficiency virus, hemoglobinopathies, and immunosuppression. Blood cultures are reported to be frequently positive in cases of
Salmonella
osteomyelitis. Identification of
Salmonella
species from intraoperative cultures should prompt consultation with the infectious disease department for culture-specific antibiotic tailoring. Many common antibiotic agents active against gram-negative organisms seem efficacious. As in this case, following the basic tenets of osteomyelitis management should lead to an acceptable outcome.
Comparison of the fatty acid profile of muscle neutral lipids and phospholipids of up-river anadromous sea lamprey (Petromyzon marinus L.) from three Portuguese river basins
Authors: Pinela Sara , Ruivo Quintella Bernardo , Raposo de Almeida Pedro , Lança Maria João
Published: September 2009

Composition of fatty acid profile of muscle neutral lipids (NL) and phospholipids (PL) of sea lamprey that enter the Portuguese rivers Minho, Tagus and Guadiana during their non-trophic spawning migration was analysed. The fatty acid profile exhibited differences in the percentage among NL and PL and between river basins. Similarities were found in the fatty acid profile of NL. Monounsaturated fatty acids (MUFA) were the most representative, followed by saturated fatty acids (SFA) and finally by polyunsaturated fatty acids (PUFA). Monoenic 16:1 and 18:1ω9 formed a considerable percentage of total fatty acids, followed by SFA 14:0 and 16:0. EPA and DHA were the dominant PUFA fatty acids. In terms of NL, the fatty acid that contributed for the discrimination between the three river basins was 18:1ω7. Individuals from the Minho river basin exhibited a different fatty acid profile of PL characterised by a low PUFA percentage when compared with lampreys from the Tagus and Guadiana river basins. Muscle PL fraction showed that the two monoenes, 16:1 and 18:1ω9, occurred at high percentage, followed by 16:0 and 14:0 (SFA). Among PUFA, DHA was the most representative fatty acid. The fatty acids that contributed to the separation between the three river basins were 16:0, 18:4ω3 and 24:1ω9. Although the results point in the direction of a possible difference between the fatty acid composition of the NL and PL fractions in the muscle samples from the three river basins, further studies, especially in tissues where fatty acid composition will be less sensitive to diet and environmental factors, are necessary to confirm this hypothesis.
Improved Survival and Reduced Vascular Permeability by Eliminating or Blocking 12/15-Lipoxygenase in Mouse Models of Acute Lung Injury (ALI)
Authors: Zarbock Alexander , DiStasi Matthew R. , Smith Emily , Sanders John M. , Kronke Gerhard , Harry Brian L. , von Vietinghoff Sibylle , Buscher Konrad , Nadler Jerry L. , Ley Klaus
Published: September 2009

Acute lung injury (ALI) is a prevalent disease associated with high mortality. 12/15-lipoxygenase (12/15-LO) is an enzyme producing 12-hydroxyeicosatetraenoic acid (HETE) and 15-HETE from arachidonic acid. To test whether 12/15-LO is involved in increasing vascular permeability in the lung, we investigated the role of 12/15-LO in murine models of LPS-induced pulmonary inflammation and clinically relevant acid-induced ALI. The vascular permeability increase upon LPS inhalation was abolished in Alox15−/− mice lacking 12/15-LO and in wild-type mice after pharmacological blockade of 12/15-LO. Alox15−/− mice also showed improved gas exchange, reduced permeability increase, and prolonged survival in the acid-induced ALI model. Bone marrow chimeras and reconstitution experiments revealed that 12-HETE produced by hematopoietic cells regulates vascular permeability through a CXCR2-dependent mechanism. Our findings suggest that 12/15-LO-derived 12-HETE is a key mediator of vascular permeability in acute lung injury.
IL-13-Induced Oxidative Stress via Microglial NADPH Oxidase Contributes to Death of Hippocampal Neurons In Vivo
Authors: Park Keun W. , Baik Hyung H. , Jin Byung K.
Published: September 2009

In the present study, we investigated the effects of IL-13, a well-known anti-inflammatory cytokine, on the thrombin-treated hippocampus in vivo. NeuN immunohistochemistry and Nissl staining revealed significant loss of hippocampal CA1 neurons upon intrahippocampal injection of thrombin. This neurotoxicity was accompanied by substantial microglial activation, as evident from OX-42 immunohistochemistry results. In parallel, Western blot analysis and hydroethidine histochemistry disclosed activation of NADPH oxidase, generation of reactive oxygen species, and oxidative damage in the hippocampal CA1 area showing hippocampal neuron degeneration. Interestingly, immunohistochemical and biochemical experiments showed that intrahippocampal injection of thrombin increased IL-13 immunoreactivity and IL-13 levels as early as 8 h after thrombin, reaching a peak at 7 days, which was maintained up to 14 days. Moreover, double-label immunohistochemistry revealed IL-13 immunoreactivity exclusively in activated microglia. IL-13-neutralizing Abs significantly rescued CA1 hippocampal neurons from thrombin neurotoxicity. In parallel, neutralization of IL-13 inhibited activation of NADPH oxidase, reactive oxygen species production, and oxidative damage. Additionally, IL-13 neutralization suppressed the expression of inducible NO synthase and several proinflammatory cytokines. To our knowledge, the present study is the first to show that IL-13 triggers microglial NADPH oxidase-derived oxidative stress, leading to the degeneration of hippocampal neurons in vivo, as occurs in cases of Alzheimer’s disease.
Critical Role of TLR4 Response in the Activation of Microglia Induced by Ethanol
Authors: Fernandez-Lizarbe Sara , Pascual Maria , Guerri Consuelo
Published: September 2009

Microglial cells are the primary immune effector cells in the brain and play a pivotal role in the neuroinflammatory processes associated with a variety of neurological and pathological disorders. Alcohol consumption induces brain damage, although the neuropathological processes are poorly understood. We previously suggested that ethanol promotes inflammatory processes in the brain, up-regulating inflammatory mediators and signaling pathways associated with IL-1RI/TLR4 receptors. In the present study we investigate whether ethanol induces microglia activation by stimulating TLR4 response and whether this response causes neuronal death and contributes to ethanol-induced neuroinflammatory damage. We demonstrate that ethanol activates microglía and stimulates NF-κB, MAPKs, and MyD88-independent (IFN regulatory factor-3, IFN-β) pathways to trigger the production of inflammatory mediators, causing neuronal death. The inflammatory response induced by ethanol is completely abrogated in microglia of TLR4-deficient mice (TLR4−/−), thus supporting the role of these receptors in microglia activation and neuronal death. In accord with the in vitro findings, acute ethanol administration induces microglia activation (CD11b+ cells) in cerebral cortex of TLR4+/+ mice, but not in TLR4−/− mice. Taken together, our results not only provide the first evidence of the critical role of the TLR4 response in the ethanol-induced microglia activation, but also new insight into the basic mechanisms participating in ethanol-induced neuroinflammatory damage.
T Cell Infiltrates in the Muscles of Patients with Dermatomyositis and Polymyositis Are Dominated by CD28null T Cells
Authors: Fasth Andreas E. R. , Dastmalchi Maryam , Rahbar Afsar , Salomonsson Stina , Pandya Jayesh M. , Lindroos Eva , Nennesmo Inger , Malmberg Karl-Johan , Söderberg-Nauclér Cecilia , Trollmo Christina , Lundberg Ingrid E. , Malmström Vivianne
Published: September 2009

Dermatomyositis and polymyositis are disabling rheumatic diseases characterized by an appreciable number of T cells infiltrating muscle tissue. The precise phenotype, function and specificity of these cells remain elusive. In this study, we aimed to characterize T cells in muscle tissue and circulation and to investigate their association to clinical phenotype. Twenty-four patients with dermatomyositis and 42 with polymyositis were screened for frequency of CD4+CD28null and CD8+CD28null T cells in peripheral blood by flow cytometry. Presence of these cells in inflamed muscle tissue from 13 of these patients was analyzed by three-color immunofluorescence microscopy. Effector functions, proliferation and Ag specificity were analyzed by flow cytometry after in vitro stimulation. The clinical relevance of CD28null T cells was analyzed by multiple regression analyses including six separate and combined disease variables. We demonstrate that muscle-infiltrating T cells are predominantly CD4+CD28null and CD8+CD28null T cells in patients with dermatomyositis and polymyositis. Muscle-infiltrating CD28null T cells were found already at time of diagnosis. Disease activity correlated with the frequency of CD8+ T cells in the inflamed muscles of polymyositis patients. Circulating CD4+CD28null and CD8+CD28null T cells were significantly more frequent in human CMV (HCMV) seropositive individuals, responded to HCMV Ag stimulation, and correlated with disease duration. These cells also display a proinflammatory cytokine profile, contain perforin and lack the costimulatory molecule CD28. Our observations imply that CD28null T cells represent clinically important effector cells in dermatomyositis and polymyositis, and that HCMV might play a role in propagating disease in a subset of patients.
The Immunological Impact of Genetic Drift in the B10.BR Congenic Inbred Mouse Strain
Authors: Fanning Stacey L. , Appel Michael Y. , Berger Stephanie A. , Korngold Robert , Friedman Thea M.
Published: September 2009

The MHC-matched, minor histocompatibility Ag (miHA)-mismatched B10.BR→CBA strain combination has been used to elucidate the immunobiology of graft-vs-host disease (GVHD) following allogeneic bone marrow transplantation. Studies conducted in the 1980s had established that B10.BR CD8+ T cells were capable of mediating GVHD in the absence of CD4+ T cells, and that CD4+ T cells were unable to induce lethal disease. In more recent studies with this GVHD model, we detected etiological discrepancies with the previously published results, which suggested that genetic drift might have occurred within the B10.BR strain. In particular, there was increased allorecognition of CBA miHA by B10.BR CD4+ T cells, as determined by both TCR Vβ spectratype analysis and the induction of lethal GVHD in CBA recipients. Additionally, alloreactivity was observed between the genetically drifted mice (B10.BR/Jdrif) and mice rederived from frozen embryos of the original strain (B10.BR/Jrep) using Vβ spectratype analysis and IFN-γ ELISPOT assays, suggesting that new miHA differences had arisen between the mice. Furthermore, T cell-depleted B10.BR/Jdrif bone marrow cells were unable to provide long-term survival following either allogeneic or syngeneic bone marrow transplantation. Gene expression analysis revealed several genes involved in hematopoiesis that were overexpressed in the lineage-negative fraction of B10.BR/Jdrif bone marrow, as compared with B10.BR/Jrep mice. Taken together, these results suggest that genetic drift in the B10.BR strain has significantly impacted the immune alloreactive response in the GVHD model by causing altered expression of miHA and diminished capacity for survival following transplantation into lethally irradiated recipients.
Bacterial Surface Protein L Binds and Inactivates Neutrophil Proteins S100A8/A9
Authors: Åkerström Bo , Björck Lars
Published: September 2009

Finegoldia magna is an anaerobic bacterial species that is part of the normal human flora on all nonsterile body surfaces, but it is also a significant opportunistic pathogen causing a wide range of infections. Some isolates of F. magna that are more frequently associated with clinical infection express protein L, a surface protein containing multiple homologous domains (B1-B5) that bind Igs through interactions with Ig L chains. The present study shows that the N-terminal A domain of protein L binds S100A8/A9, antibacterial proteins present in large amounts in the cytoplasm of neutrophils, but also extracellularly in tissues during inflammation. As a result, protein L-expressing F. magna are protected against killing by S100A8/A9. Igs and S100A8/A9 were found to interact independently with protein L, demonstrating that this bacterial surface protein is capable of manipulating both adaptive and innate immune defense mechanisms.
Zinc‐Binding Protein
Znu
A
Authors: Smith Thomas J , Pakrasi Himadri B
Published: September 2009

ZnuA is a high‐affinity, periplasmic zinc (Zn
2+
)‐binding protein that is a component of a three‐protein ABC transport system. The overall structure of ZnuA is very similar to the previously determined structures of the periplasmic domains of the ABC metal transporters PsaA and TroA. ZnuA has a ‘C clamp’ shape, which is composed of two (β/α)
4
domains related by pseudo twofold symmetry. Also like the other metal transporters, the two domains are linked by a 33‐residue α‐helix. This likely keeps the two domains in a relatively fixed position as made evident by the lack of large domain movement upon binding and release of metal. Unlike PsaA and TroA, however, there is an extended loop near the metal‐binding cleft, which is rich in histidines and acidic residues. Structural studies demonstrate that the removal of this loop does not affect the structure of ZnuA, and isothermal titration calorimetry (ITC) studies show that this loop contains low‐affinity zinc‐binding sites but does not directly affect the binding of zinc to the high‐affinity site within the cleft. Together, these results suggest that this unusual loop region may play a role in the regulation of zinc uptake when the periplasmic concentration of zinc is high.
Groundwater Protection
Authors: Stauffer Fritz
Published: September 2009

Despite all the technical, legal, and social difficulties, and the costs, which arise or which could arise from restoring contaminated groundwater, it is obvious that the timely protection of the groundwater environment is preferable. National regulations define the framework for the protection of aquifers and especially drinking water wells. On the one hand, there are existing or planned activities, which represent hazards or risks for a particular groundwater environment, and, on the other hand, the aquifers exhibit a certain degree of vulnerability to a wide range of chemical and biological pollutants. Accordingly, the basic steps toward the protection of groundwater environments are (i) characterization of the site under consideration, (ii) assessment of the existing and potential groundwater contaminations or contamination risks, (iii) evaluation of the use of groundwater of the site, and (iv) evaluation and implementation of the groundwater protection measures.
Ecohydrological Optimality
Authors: Schymanski Stanislaus J. , Kleidon Axel , Roderick Michael L.
Published: September 2009

Hydrological systems are governed by an incredible wealth of interactive processes, ranging from small‐scale processes within the soil domain such as unsaturated flow, bioturbation, and root water uptake to large‐scale feedbacks between the water balance and the global atmospheric circulation. Optimality approaches aim toward a simpler and more general representation of hydrological systems. As the hydrology of land is strongly affected by the presence of vegetation, these optimality approaches generally need to be explored in the context of how purely hydrological processes are linked to ecological processes. This article summarizes the different optimality assumptions that have been used to describe ecohydrological processes and how these are related to each other. Most approaches can be classified as either physical or ecological optimality. A range of examples are given for applying optimality approaches at various temporal and spatial scales, ranging from the scale of individual leaves and how they control water loss in relation to carbon uptake to the larger scale attributes of vegetation types, ecosystem properties, and river basin networks. The article concludes with a discussion of the usefulness of optimality approaches and their advantages as well as their disadvantages and the need for improvement.
Field‐Portable Instrumentation for Gas and Vapor Samples
Authors: Thompson Cyril V. , Goedert Michel G.
Published: September 2009

The analysis of gas and vapors in the field is an important part of the environmental characterization and remediation process. The purpose of this article is to familiarize the reader with some of the analytical instrumentation currently used to determine the composition of gaseous samples. Although this section deals with portable instruments, on‐site measurements warrant a brief mention. These measurements are often conducted with conventional analytical instruments operating from recreational vehicles. The samples have to be collected and transported to the instrument, and the first part of this article gives an overview of some of the techniques, such as canister and solid adsorbents, used for this purpose. Identification of compounds collected on‐site or directly in the field can be done by gas chromatography (GC) and mass spectrometry (MS). A more comprehensive description of these laboratory‐based techniques is found in a previous version of this article. An important part of the portable section covers direct‐reading instruments such as gas sensors, electrochemical devices, ionization detectors, and colorimetric detectors. These instruments provide a limited amount of information and, most of the time, require prior knowledge of the content of the sample. However, they are small, portable, and cheaper than laboratory analytical instruments and therefore they have found a market. Portable instruments include miniaturized gas chromatographs and mass spectrometers. These instruments do not offer the high performance of their laboratory counterparts, but they give more information about the sample than direct‐reading instruments. The next step in process measurement sophistication is to combine these techniques. The most popular hyphenated technique is coupling of a gas chromatograph with a mass spectrometer, but there are also powerful and lesser‐known techniques such as GC combined with ion mobility spectrometry (IMS). IMS has found a market in military applications for the detection of chemical warfare agents. It offers less resolution than MS but operates at atmospheric pressure and is therefore truly portable. When combined with GC, it offers some interesting features which are described later.
Nuclear Magnetic Resonance, Imaging of Polymers
Authors: Blümler Peter , Hafner Siegfried
Published: September 2009

Nuclear magnetic resonance (NMR) imaging is a noninvasive technique, which is based on the phenomenon of NMR. The resonance frequencies of the nuclear spins can be made spatially dependent by introducing a magnetic‐field gradient into the NMR experiment. The acquired NMR signal is thus spatially encoded and a spin‐density image of the sample can be reconstructed.

While originally developed for medical applications, NMR imaging is now increasingly applied for materials investigations. The main advantages of the technique are its nondestructivity, which allows processes to be investigated in situ, and the possibility of introducing NMR spectroscopic information and relaxation contrast into the NMR images. The limitations, on the other hand, are the relatively low sensitivity and the broad NMR lines of polymers, both of which limit the spatial resolution. Whereas the latter can be dealt with by suitable methods, the sensitivity ultimately restricts the achievable spatial resolution of conventional NMR imaging techniques to about (10 µm)3. NMR imaging therefore must not be considered as a competitor of other microscopic techniques such as electron microscopy but as a characterization technique that provides supplementary information. Examples illustrating all these aspects are given in this article.
Glow Discharge Optical Spectroscopy and Mass Spectrometry
Authors: Steiner Robert E. , Barshick Christopher M. , Bogaerts Annemie
Published: September 2009

Optical (atomic absorption spectroscopy, AAS; atomic emission spectroscopy, AES; atomic fluorescence spectroscopy, AFS; and optogalvanic spectroscopy) and mass spectrometric (magnetic sector, quadrupole mass analyzer, QMA; quadrupole ion trap, QIT; Fourier transform ion cyclotron resonance, FTICR; and time‐of‐flight, TOF) instrumentation are well suited for coupling to the glow discharge (GD).

The GD is a relatively simple device. A potential gradient (500–1500 V) is applied between an anode and a cathode. In most cases, the sample is also the cathode. A noble gas (e.g. Ar, Ne, and Xe) is introduced into the discharge region before power initiation. When a potential is applied, electrons are accelerated toward the anode. As these electrons accelerate, they collide with gas atoms. A fraction of these collisions are of sufficient energy to remove an electron from a support gas atom, forming an ion. These ions are, in turn, accelerated toward the cathode. These ions impinge on the surface of the cathode, sputtering sample atoms from the surface. Sputtered atoms that do not redeposit on the surface diffuse into the excitation/ionization regions of the plasma where they can undergo excitation and/or ionization via a number of collisional processes.

GD sources offer a number of distinct advantages that make them well suited for specific types of analyses. These sources afford direct analysis of solid samples, thus minimizing the sample preparation required for analysis. The nature of the plasma also provides mutually exclusive atomization and excitation processes that help to minimize the matrix effects that plague so many other elemental techniques. Unfortunately, the GD source functions optimally in a dry environment, making analysis of solutions more difficult. These sources also suffer from difficulties associated with analyzing nonconducting samples.

In this article, first, the principles of operation of the GD plasma are reviewed, with an emphasis on how those principles relate to optical spectroscopy and mass spectrometry. Basic applications of the GD techniques are considered next. These include bulk analysis, surface analysis, and the analysis of solution samples. The requirements necessary to obtain optical information are addressed following the analytical applications. This section focuses on the instrumentation needed to make optical measurements using the GD as an atomization/excitation source. Finally, mass spectrometric instrumentation and interfaces are addressed as they pertain to the use of a GD plasma as an ion source.

GD sources provide analytically useful gas‐phase species from solid samples. These sources can be interfaced with a variety of spectroscopic and spectrometric instruments for both quantitative and qualitative analysis.
Silica Gel and its Derivatization for Liquid Chromatography
Authors: Neue Uwe D.
Published: September 2009

In this article, we review the preparation and use of silica and hybrid packings and their derivatives in liquid chromatography (LC). First, the properties of the carrier that are important for its application in LC are examined and then bonded phases and coated phases based on silica and hybrid packings are considered. The current state of the art of the preparation of bonded phases and coated phases is surveyed, and the properties that are relevant for the chromatographer are discussed. Owing to the popularity of reversed‐phase liquid chromatography (RPLC), most of the emphasis is placed on phases used in this technique; however, other chromatographic techniques are not ignored. A detailed characterization of reversed‐phase packings is provided.
Nuclear Reaction Spectroscopy
Authors: Trocellier Patrick , Berger Pascal
Published: September 2009

Among ion‐beam‐based analytical methods, direct observation of nuclear reactions induced by highly energetic (Me V domain) charged particles is dedicated to quantitative determination of volumic distributions of light elements fromZ = 1 (H) toZ = 41 (Ga) in the near surface region of solids. In most cases, discrimination between their isotopes is enabled up to37Cl. The incident ions are generally protons, deuterons, helium‐3, or helium‐4 ions. Nuclear reactions induced by heavier ions are rarely used, mostly for hydrogen depth profiling. All these reactions are characterized by the prompt emission of charged particles (protons or helium‐4 ions) and/or γ‐rays. Nuclear reaction analysis (NRA), performed in ion millibeam or microbeam modes, is an efficient complement to charged‐particle‐induced X‐ray emission, Rutherford backscattering spectrometry, and elastic recoil detection methods. Its applications are all intended for either absolute quantification or tracing experiments. They cover a broad panorama from life sciences to cultural heritage artifacts, including metallurgy, Earth sciences, nanotechnology, and material science.
Particle‐InducedX‐Ray Emission (PIXE)
Authors: Mandò Pier A. , Przybyłowicz Wojciech J.
Published: September 2009

Particle‐induced X‐ray emission (PIXE) is the most popular among the ion beam analysis (IBA) techniques, which are based on the use of the specimen to be analyzed as a target for a beam of accelerated particles. The detection of the radiation induced by the beam bombardment is then used to discriminate and quantify the presence of the different elements in the specimen. In PIXE, what is exploited is, in particular, the X‐rays emitted from the target, whose energies are characteristic of the emitting atomic species. After a general, simple description of the main features of PIXE, with a short historical overview and a brief comparison to other X‐ray fluorescence (XRF) techniques, the article covers in greater depth all the specific aspects of this technique. The basic aspects of X‐ray emission from the atoms are first recalled; then, the extraction of quantitative compositional data from thin and thick specimens is explained, and a discussion is given of the excellent performance of PIXE in terms of minimum detection limits, and of the factors affecting them. A technical description then follows of how proper beams for PIXE are produced and of the experimental setups commonly used. The X‐ray detector characteristics, the electronics for constructing the energy spectra, and the software processes for their deconvolution, leading to the extraction of quantitative data, are then briefly described. The last section surveys the main analytical applications of PIXE in various fields (environmental monitoring, biomedicine, earth sciences, cultural heritage, and materials analysis), with no intent of exhaustiveness but rather with the purpose of focusing on when and why PIXE may be particularly suitable in each of them.
Magic‐Angle Spinning Solid‐State Nuclear Magnetic Resonance: Application to Structural Biology
Authors: Goldbourt Amir
Published: September 2009

The application of magic‐angle spinning (MAS) solid‐state NMR methods to large‐scale problems in structural biology has seen a significant progress in the last decade. Improved hardware, better sample preparation techniques, and new methodologies have resulted in the ability to solve the three‐dimensional structures of proteins, and to study their dynamic properties, making this method a viable and important tool for understanding the relation between biological processes and protein structure and function. One of the biggest advantages of MAS solid‐state NMR is in the ability to study structures, which are not easily accessible by traditional methods such as X‐ray crystallography and solution NMR. Hence, new classes of important proteins and biological complexes such as membrane proteins, amyloid fibrils and prions, metalloenzymes, and viruses, have all been characterized to various extents. It is expected that the role of MAS solid‐state NMR in structural biology will increase significantly as the number of dedicated research groups rises, and methodologies and hardware further improve.
Quadrupolar Nuclei in Biological Systems
Authors: Wu Gang
Published: September 2009

Recent advances in solid‐state nuclear magnetic resonance (NMR) methodology and improvement in high‐field NMR instrumentation have generated a new wave of research interests in the application of solid‐state NMR to the study of quadrupolar nuclei in biological systems. These developments now permit increasingly complex biological systems to be probed by direct NMR detection of quadrupolar nuclei. In this article, we describe some recent progress in solid‐state NMR studies of17O (S = 5/2),25Mg (S = 5/2),43Ca (S = 7/2),67Zn (S = 5/2),23Na (S = 3/2), and39K (S = 3/2) nuclei in biological systems with a prognosis for future directions.
Diffusion and Electrophoretic Studies Using Nuclear Magnetic Resonance
Authors: Stilbs Peter
Published: September 2009

The NMR diffusometry methodology and instrumentation currently available is routinely capable of quite fast multicomponent self‐diffusion mapping in solution, providing a quantitative pathway to many analytical applications as well as physicochemical information. A measurement time span of approximately 10 min may suffice, and an accuracy of a few percent or better is normally routinely achievable. Relating the behavior of self‐diffusion coefficients of solution components to, e.g. solution composition changes adds another dimension to the field and a path to quantitative methods for elucidation of, e.g. molecular association or conformational changes even in complex systems. In routine form, the techniques are primarily applicable to liquid systems and use proton (1H) NMR detection. A limited number of nuclei other than protons (primarily2H,7Li,13C,19F,31P) are also amenable for monitoring. Electrophoretic NMR (eNMR) is a related, less exploited technique, which has a more limited applicability than NMR diffusometry, but which can be uniquely useful. Instrumental and methodological advances have lately also opened up the application field to proton‐detected diffusion studies in semisolid systems.
Production of Radionuclides for Tracers
Authors: Alfassi Zeev B. , Groppi F.
Published: September 2009

This chapters deals with production of radionuclides by both neutron bombardment from nuclear reactors and heavy charged accelerated atoms from accelerators. In the case of neutrons, most radionuclides have low specific activity due to the present carrier. The production of carrier‐free radionuclides is described.
Electrochemical Gas Sensors
Authors: Opekar František , Štulík Karel
Published: September 2009

Fundamental properties and structures of potentiometric and amperometric sensors for detection of compounds in gaseous phase are discussed. The discussion primarily deals with membrane sensors containing liquid electrolytes and solid‐state sensors employing inorganic and solid polymer electrolytes. Applications of gas sensors for detection of compounds in solution are also briefly discussed. Numerous practical examples are listed in tables. The advantages and drawbacks of various detector designs are critically surveyed and the important trends for further development are briefly outlined.
Catalytic Surfaces for Electroanalysis
Authors: Cox James A. , Kulesza Pawel J.
Published: September 2009

In this article, electrochemical determinations based on oxidation or reduction processes that require a catalyst to obtain a current proportional to analyte concentration are described. The scope is restricted to cases where the catalyst is immobilized at the electrode surface. In general, oxidation or reduction of a substance at an electrode surface can be the basis of an analytical method as long as the electron‐transfer reaction occurs in the potential window between redox of the solvent, supporting electrolyte, and/or the electrode material. The need for a catalyst arises because only a small fraction of solutes that are predicted on the basis of standard potentials to undergo redox in an available potential window are electrolyzed in the absence of a catalyst at a sufficient rate to provide an analytically useful current. As described later, the common mode of promotion of the rate of electron transfer is by mediation. A problem that results when immobilized mediators are used is that the potential at which the current is produced is related to the mediator as well as to the analytes; hence, many practical applications of catalytic surfaces involve electrochemical detection after separation by methods such as high‐performance liquid chromatography (HPLC).
The influence of text legibility on eye movements during reading
Authors: Slattery Timothy J. , Rayner Keith
Published: September 2009

Subjects read passages of text on a video monitor as their eye movements were recorded. In Experiment 1, the passages were presented either in a format (ClearType) designed to display smoother, clearer characters on LCD monitors by eliminating pixilation or in standard format (non‐ClearType). The passages were also presented in three different fonts (Times New Roman, Harrington and Script MT bold) which differed in how easy the letters were to encode. While there were no comprehension differences due to ClearType or font, ClearType led to faster reading, fewer fixations, and shorter fixation durations than non‐ClearType. There were also font differences, with Times New Roman leading to faster reading than the other two fonts. In Experiment 2, we replicated the results that ClearType lead to faster reading than non‐ClearType when subjects read single sentences with high or low frequency target words. Across both experiments, word frequency interacted with presentation format. Copyright © 2009 John Wiley & Sons, Ltd.
Bulk Metallic Glasses with Functional Physical Properties
Authors: Wang W. H.
Published: September 2009

In this review, we report on the formation of a variety of novel, metallic, glassy materials that might well have applications as functional materials. The metallic glasses, with excellent glass‐forming ability, display many fascinating properties and features such as excellent wave‐absorption ability, exceptionally low glass‐transition temperatures (∼35–60 °C) approaching room temperature, ultralow elastic moduli comparable to that of human bone, high elasticity and high strength, superplasticity and polymer‐like thermoplastic formability near room temperature, an excellent magnetocaloric effect, hard magnetism and tunable magnetic properties, heavy‐fermion behavior, superhydrophobicity and superoleophobicity, and polyamorphism, all of which are of interest not only for basic research but also for technological applications. A strategy based on elastic‐moduli correlations for fabrication of bulk metallic glasses (BMGs) with controllable properties is presented. The work has implications in the search for novel metallic glasses with unique functional properties, for advancing our understanding of the nature and formation of glasses, and for extending the applications of the materials.
Controlled Growth of High‐Quality ZnO‐Based Films and Fabrication of Visible‐Blind and Solar‐Blind Ultra‐Violet Detectors
Authors: Du Xiaolong , Mei Zengxia , Liu Zhanglong , Guo Yang , Zhang Tianchong , Hou Yaonan , Zhang Ze , Xue Qikun , Kuznetsov Andrej Yu
Published: September 2009

ZnO is a wide‐bandgap (3.37 eV at room temperature) oxide semiconductor that is attractive for its great potential in short‐wavelength optoelectronic devices, in which high quality films and heterostructures are essential for high performance. In this study, controlled growth of ZnO‐based thin films and heterostructures by molecular beam epitaxy (MBE) is demonstrated on different substrates with emphasis on interface engineering. It is revealed that ultrathin AlN or MgO interfacial layers play a key role in establishing structural and chemical compatibility between ZnO and substrates. Furthermore, a quasi‐homo buffer is introduced prior to growth of a wurtzite MgZnO epilayer to suppress the phase segregation of rock‐salt MgO, achieving wide‐range bandgap tuning from 3.3 to 4.55 eV. Finally, a visible‐blind UV detector exploiting a double heterojunction of n‐ZnO/insulator‐MgO/p‐Si and a solar‐blind UV detector using MgZnO as an active layer are fabricated by using the growth techniques discussed here.
Epitaxial Growth and Properties of Doped Transition Metal and Complex Oxide Films
Authors: Chambers Scott A.
Published: September 2009

The detailed science and technology of crystalline oxide film growth using vacuum methods is reviewed and discussed with an eye toward gaining fundamental insights into the relationships between growth process and parameters, film and interface structure and composition, and electronic, magnetic and photochemical properties. The topic is approached first from a comparative point of view based on the most widely used growth methods, and then on the basis of specific material systems that have generated very high levels of interest. Emphasis is placed on the wide diversity of structural, electronic, optical and magnetic properties exhibited by oxides, and the fascinating results that this diversity of properties can produce when combined with the degrees of freedom afforded by heteroepitaxy.
Modeling and simulation of the formation and utilization of microbial products in aerobic granular sludge
Authors: Ni Bing‐Jie , Yu Han‐Qing
Published: September 2009

A mathematical model is established to simulate the formation of extracellular polymeric substances (EPS), soluble microbial products (SMP), and internal storage products (XSTO) in aerobic granular sludge. The sensitivity of these microbial products concentrations toward the key model parameters is analyzed. Independent experiments are conducted to find required parameter values and to test its predictive ability. The model is evaluated by using one‐cycle operating experimental results of a lab‐scale aerobic granule‐based sequencing batch reactor (SBR) and batch experimental results. Results show that the model is able to describe the microbial product dynamics in aerobic granules and provide further insights into a granule‐based SBR. The effect of the initial substrate and biomass concentrations on the formation of microbial products in aerobic granular sludge can therefore be analyzed by model simulation. A higher substrate concentration results in a greater concentration of EPS, SMP, and XSTO. An accumulation of biomass in the bioreactor leads to an increased production rate of EPS, SMP, and XSTO. © 2009 American Institute of Chemical Engineers AIChE J, 2010