bluuebunny/crossref_metadata_2025 huggingface dataset:
Stripping Analysis Enhanced by Ultrasound, Electrode Heating and Magnetic Fields
Authors: Grundler Peter
Published: July 2008

Stripping analysis is a two-step procedure. In the first step, the analyte is accumulated at an electrode surface either by electrolysis or by adsorption. In the second step, the deposited material is removed, typically by electrolysis. The second step is the source of the analytical signal. Sensitivity of the method mainly depends on the amount of substance which is transferred to the electrode surface during accumulation. The methods reviewed make use of unconventional techniques to enhance efficiency of accumulation. By ultrasound, a combined action of thermal and mechanical impacts, partially with extreme energetic states, causes improvement of analytical results. Heating of electrodes or of a nearelectrode area induces laminar electrolyte flow acting as stirring, combined with increased surface temperature that is helpful to lower kinetic hindrances. Magnetic fields in a cell with arbitrarily increased deposition current enhances convection without additional thermal effects. Most of the techniques reviewed are able to improve the efficiency of stripping analysis much more than could be done by driving classical stirring up to the limits.
Fabrication and Applications of Nanoparticle-Modified Electrodes in Stripping Analysis
Authors: Ward Jones Sarah E. , Compton Richard G.
Published: July 2008

In recent years significant work had been carried out on the fabrication and application of nanoparticlemodified electrodes for trace heavy metal detection with the view to producing sensitive and versatile sensors. Much has focused on the use of gold nanoparticles for the detection of arsenic and other toxins, however silver, platinum and bismuth nanoparticles have also been researched. This review covers a range of different nanoparticle fabrication and electrode modification methods for the production of electrodes which have been applied using stripping voltammetry. Particular attention is paid to their applications and success as sensors.
Stripping Analysis using Boron-Doped Diamond Electrodes
Authors: Ward Jones Sarah E. , Compton Richard G.
Published: July 2008

Boron-doped diamond (BDD) is one of a number of solid electrode materials that have been developed as alternatives to mercury electrodes for electroanalysis. Electrodes made from boron-doped diamond possess many attractive properties including a wide potential window, low background currents, high resistance to electrode fouling, ease of chemical modification, long term stability and the hard and flat nature of the electrode surface. This review covers work on a wide range of analytical applications and enhancement techniques for stripping voltammetry at boron-doped diamond electrodes including the use of power ultrasound, microwave radiation, lasers and microelectrode arrays.
Impact of Diabetes and Its Treatment on Cognitive Function Among Adolescents Who Participated in the Diabetes Control and Complications Trial
Authors: Musen Gail , Jacobson Alan M. , Ryan Christopher M. , Cleary Patricia A. , Waberski Barbara H. , Weinger Katie , Dahms William , Bayless Meg , Silvers Nancy , Harth Judith , White Neil ,   the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) Research Group
Published: July 2008

OBJECTIVE—The purpose of this study was to evaluate whether severe hypoglycemia or intensive therapy affects cognitive performance over time in a subgroup of patients who were aged 13–19 years at entry in the Diabetes Control and Complications Trial (DCCT).

RESEARCH DESIGN AND METHODS—This was a longitudinal study involving 249 patients with type 1 diabetes who were between 13 and 19 years old when they were randomly assigned in the DCCT. Scores on a comprehensive battery of cognitive tests obtained during the Epidemiology of Diabetes Interventions and Complications follow-up study, ∼18 years later, were compared with baseline performance. We assessed the effects of the original DCCT treatment group assignment, mean A1C values, and frequency of severe hypoglycemic events on eight domains of cognition.

RESULTS—There were a total of 294 reported episodes of coma or seizure. Neither frequency of hypoglycemia nor previous treatment group was associated with decline on any cognitive domain. As in a previous analysis of the entire study cohort, higher A1C values were associated with declines in the psychomotor and mental efficiency domain (P < 0.01); however, the previous finding of improved motor speed with lower A1C values was not replicated in this subgroup analysis.

CONCLUSIONS—Despite relatively high rates of severe hypoglycemia, cognitive function did not decline over an extended period of time in the youngest cohort of patients with type 1 diabetes.
Four-Factor Structure of the Correctional Personnel Rating Scale
Authors: Mitchell Tom , Yun Gunna J. , Pinkos Erica
Published: July 2008

Correctional officer performance appraisals often neglect to target important job behaviours, particularly those involving ineffective as well as effective work behaviours, and interactions with other staff and inmates. The Correctional Personnel Rating Scale (CPRS) was designed to capture these behaviours as well as traditional routine task-related behaviours. Two performance ratings were obtained, using the CPRS, for each of 742 correctional officers. An exploratory factor analysis identified four factors that reliably assessed (1) desirable work behaviours, (2) undesirable work behaviours, (3) emotional control, and (4) inmate relations. Findings indicate that the CPRS is an effective, comprehensive tool for assessing correctional officers’ job performance.
Correlation between Climate and Crime in Eastern Tokyo
Authors: Ikegaya Hiroshi , Suganami Hideki
Published: July 2008

Many reports have indicated a correlation between climate and crime. Here, we examine the correlation between climatic factors and forensic autopsies, and show that higher rates of murder, manslaughter, and bodily injury resulting in death occur on sunny days than on non-sunny days. The largest number of autopsies was associated with days on which the weather was unstable. In addition to increased activity of people on sunny days, unstable and uncomfortable weather may result in crime through induction of psychiatric stress. More hit-and-run cases occurred on rainy days than on non-rainy days, and unstable weather may also be associated with traffic crimes. We conclude that weather factors, in addition to social factors, are important in murder and in fatalities due to hit-and-run traffic crimes.
Foramen arcuale: anatomical study and review of the literature
Authors: Tubbs R. Shane , Johnson Philip C. , Shoja Mohammadali M. , Loukas Marios , Oakes W. Jerry
Published: July 2008

Object

The neurosurgical literature is lacking information on the so-called foramen arcuale. When this foramen is present, the vertebral artery (VA) travels through it after exiting the transverse foramen of the atlas and prior to entering the cranium.

Methods

The authors performed a study in 60 cadavers to determine the incidence of the foramen arcuale and ascertain morphometric information on its anatomy. In specimens in which the foramen arcuale was observed, the authors studied the relationship between it and the VA.

The authors identified a foramen arcuale in 5% of specimens. The mean length and thickness of the osseous struts that converted the groove for the VA into the foramen arcuale were 7.0 and 2.0 mm, respectively. The mean area of the identified foramina was 14.2 mm2. The mean area of the ipsilateral C-1 transverse foramina was 18 mm2 in specimens with a foramen arcuale. The mean measurements of the proximal, intraforaminal (foramen arcuale), and distal diameter of the V3 segment of the VA at the level of the foramen arcuale were 6, 4, and 5 mm, respectively. In all specimens the authors noted that the intraforaminal part of the V3 segment was grossly compressed.

Conclusions

The authors found that the foramen arcuale may compress the V3 segment of the VA. Based on their postmortem study, however, they cannot conclude that compression at this location results in symptomatic VA insufficiency. Based on their review of the literature, it seems that symptomatic compression of the VA at this location may be alleviated in some patients with decompressive procedures.
Intramedullary abscess in association with tumor at the conus medullaris
Authors: Mohindra Sandeep , Gupta Rahul , Mathuriya Suresh Narain , Radotra Bishan Dass
Published: July 2008

✓The authors report on two patients with intramedullary tumors complicated by abscess formation. Both patients experienced abrupt onset of neurological deterioration and poor surgical outcome. An intratumoral abscess developed in one, whereas the other had a tumor-associated syrinx in which an intramedullary abscess developed. Such a conversion of a syrinx into an abscess has not been reported earlier. It is septicemia that underlies all such catastrophic complications; therefore, rapid neurological deterioration should always be looked on with caution and investigated with contrast-enhanced magnetic resonance imaging. Despite poor neurological outcome in such patients, urgent surgical intervention is mandatory.
Anterior approaches to fusion of the cervical spine: a metaanalysis of fusion rates
Authors: Fraser Justin F. , Härtl Roger
Published: July 2008

Object

Anterior cervical discectomy (ACD), ACD with interbody fusion (ACDF), ACDF with placement of an anterior plate system (ACDFP), corpectomy, and corpectomy with plate placement are used to fuse the cervical spine. The authors conducted a metaanalysis of studies published after 1990 in which fusion rates achieved with each procedure were reported for patients with degenerative disease at one, two, and three disc levels.

Methods

Twenty-one papers each included data on at least 25 patients. In each of the 21 studies the average clinical follow up was more than 12 months, and the results were evaluated according to radiographic evidence of fusion and delineated by the number of levels fused. Chi-square and Fisher exact tests were used for comparisons. The mean age of the patients was 46.7 years, 46.6% were female, and the mean follow-up period was 39.6 months. The studies included 2682 patients and the overall fusion rate was 89.5%. For single disc–level disease, fusion rates were 84.9% for ACD, 92.1% for ACDF, and 97.1% for ACDFP (p = 0.0002). For two disc–level disease, fusion rates were 79.9% for ACDF, 94.6% for ACDFP, 95.9% for corpectomy, and 92.9% for corpectomy with plate placement (p = 0.0001). For three disc–level disease, fusion rates were 65.0% for ACDF, 82.5% for ACDFP, 89.8% for corpectomy, and 96.2% for corpectomy with plate placement (p = 0.0001). The use of anterior plates significantly improved fusion for one-level (p < 0.0001), two-level (p < 0.0001), and three-level (p < 0.05) ACDF. There was no significant difference in fusion rates between two-level ACDF and corpectomy with plate placement.

Conclusions

The anticipated fusion rate is one of several factors that may guide surgical decision making. Anterior cervical decompression and fusion results in high fusion rates. The results of the authors' study show that regardless of the number of levels fused, the use of an anterior cervical plate system significantly increases the fusion rate. For two-disc–level disease, there was no significant difference between ACD with a plate system or corpectomy with a plate system. For three-disc–level disease, however, the evidence suggests that corpectomy with plate placement is associated with higher fusion rates than discectomy with plate placement.
Cervical high-intensity intramedullary lesions without spinal cord compression in achondroplasia
Authors: van Dijk J. Marc C. , Lubout Charlotte M. A. , Brouwer Patrick A.
Published: July 2008

Object

In the authors' experience, the appearance of a cervical high-intensity intramedullary (CHII) lesion on magnetic resonance (MR) images in the absence of local spinal cord compression is frequently observed in patients with achondroplasia, although it has been mentioned only sporadically in the literature. Hence, the authors conducted a retrospective study in a consecutive single-center series of patients with achondroplasia to determine the prevalence and imaging features of this entity. They also reviewed the literature.

Methods

Cervical MR imaging studies obtained to establish diagnoses in 25 adult patients with achondroplasia and assessed at the Leiden University Medical Center after neurogenic claudication developed were evaluated for the presence of a CHII lesion. Imaging features of the lesion were described, and a literature search was performed.

The CHII lesion was demonstrated in 16 of 25 adult patients with achondroplasia (64%) in the absence of local spinal cord compression. All lesions were located at the C-2 level and appeared to be confined to the gray matter. The CHII lesion was associated with local spinal cord thinning, most likely representing focal atrophy. In their literature search the authors found no description of the CHII lesion in adults, although its presence has been mentioned as a peculiarity in the pediatric achondroplastic population.

Conclusions

In this large series of adults with achondroplasia and symptomatic neurogenic claudication, a CHII lesion was frequently depicted on imaging studies, but it remains a fully explored imaging phenomenon. Its cause and clinical relevance require investigation, as does its prevalence in the general achondroplastic population.
Treatment of painful osteoporotic compression and burst fractures using kyphoplasty: a prospective observational design
Authors: Stoffel Michael , Wolf Iris , Ringel Florian , Stüer Carsten , Urbach Horst , Meyer Bernhard
Published: July 2008

Object

The aim of this study was to test the hypothesis that kyphoplasty is an effective treatment in painful osteoporotic vertebral fractures, even with involvement of the posterior cortical wall.

Methods

Between December 2001 and May 2004, 74 consecutive patients were treated with kyphoplasty for 118 painful osteoporotic compression (38%) or burst (62%) fractures. Additional decompression of the spinal canal was performed in six patients, internal fixation in three. Data were collected in a prospective observational design until May 2005. The preoperative workup included neuroimaging (plain x-ray films, densitometry, short tau inversion recovery magnetic resonance imaging, and computed tomography scanning) and clinical parameters (general and neurological examinations, visual analog scale [VAS], Karnofsky Performance Scale [KPS], and 36-Item Short Form Health Survey [SF]–36). At predefined time intervals (at discharge and 6 weeks and 3, 6, 12, and 24 months post-therapy) the patients were evaluated (x-ray films, neurological status, VAS, KPS, and SF-36).

Kyphoplasty led to a significant reduction in kyphotic deformity (mean ± standard error of the mean, sagittal index: preoperative 10 ± 1°, postoperative 5 ± 1°), and an improvement in pain (VAS: preoperative 70 ± 3, postoperative 23 ± 2), activity (KPS score: preoperative 51 ± 3, postoperative 71 ± 2), and mental and physical health (SF-36, mental status: preoperative 43, postoperative 58; SF-36, physical status: preoperative 24, postoperative 35). No secondary narrowing of the spinal canal by the retropulsed posterior wall was observed after the procedure. Clinical improvement was durable (mean follow up 15 ± 1.1 months), although the VAS score secondarily increased slightly. All patients, who suffered from a compression-induced motor deficit, recovered completely during the follow-up interval. The main procedural complications consisted of one symptomatic extravertebral cement leakage (permanent monoparesis) requiring open revision, two nerve root contusions (transient radiculopathy), and one wound infection.

Conclusions

Kyphoplasty is effective in the treatment of painful osteoporotic vertebral compression and burst fractures, at least under medium-term conditions. The potential complication of procedure-related secondary narrowing of the spinal canal by the retropulsed posterior wall in burst fractures appears to be more of a theoretical than an actual risk.
Dumbbell-shaped C-2 psammomatous melanotic malignant schwannoma
Authors: Marton Elisabetta , Feletti Alberto , Orvieto Enrico , Longatti Pierluigi
Published: July 2008

✓The authors present the case of a dumbbell-shaped malignant psammomatous melanotic schwannoma of the upper cervical spine involving the C-2 sensory root. The family of the patient had a history of other malignant stromal tumors, without the Carney complex genetic pattern. The 30-year-old female patient complained of experiencing cervical pain and cervical muscle contractions for 6 months, and was admitted to the hospital. The cervical T1-weighted magnetic resonance (MR) images revealed the presence of a slightly hyperintense C2–3 intra–extradural lesion, moderately enhancing, which had eroded and enlarged the intervertebral foramen. The patient workup also included computed tomography scans and angiography. A posterior approach was used to perform a C2–3 hemilaminectomy, including opening of the dura mater and gross-total removal of the lesion. Histopathological examination of the lesion revealed it to be a malignant psammomatous melanotic schwannoma. The cerebrospinal MR image of the patient obtained at the 12-month follow-up examination demonstrated the presence of tumor progression into the subarachnoid space at the C-3 level. The strong malignancy potential of the lesion must be considered in the future management of the patient, especially due to the presence in the family of other stromal tumors such as gastrointestinalstromal tumors and malignant melanomas. The authors review all the literature concerning melanotic schwannomas and report 105 cases of melanotic schwannoma that were not related to the Carney complex. The particular focus of their review is on the characteristics of the malignant progression of melanotic schwannoma, such as local recurrences, metastasis, and survival rate.
Dramatic neurological recovery with delayed correction of traumatic lumbar spondyloptosis
Authors: Bellew Michael P. , Bartholomew Bradley J.
Published: July 2008

✓The authors describe a 36-year-old woman with traumatic lateral spondyloptosis at L-2 and complete cauda equina injury who experienced a remarkable recovery after delayed treatment. To the authors' knowledge, this is the first case of traumatic spondyloptosis at L2–3 described in the English literature. A review of previous cases of lumbar spondyloptosis suggests that the degree of anatomical injury found at surgery is a better predictor of patient outcome than fracture severity assessed radiologically. Concomitant multisystem injury is common with spine disruptions of this magnitude and may mask clinical neurological function. Even when delayed, operative decompression of these severe lesions should be considered because dramatic neurological recovery is possible.
Cervical compression myelopathy: is fusion the main prognostic indicator?
Authors: Sorar Mehmet , Seçkin Hakan , Hatipoglu Cem , Budakoglu Isil Irem , Yigitkanli Kazim , Bavbek Murad , Kars H. Zafer
Published: July 2008

Object

A variety of factors may affect the neurological improvement in patients with cervical compression myelopathy (CCM) after surgery. The aim of this study was to report and discuss the prognostic factors in a group of patients with insufficient decompression of the spinal canal.

Methods

A prospective follow up and analysis of 20 consecutive patients with CCM treated between 2000 and 2002 was performed. All patients were surgically treated via an anterior approach, either by anterior cervical discectomy and fusion with instrumentation or by cervical corpectomy and fusion with instrumentation. The surgical results were examined using the modified Japanese Orthopaedic Asssociation disability scale, with reference to the findings of magnetic resonance imaging, computed tomography, and radiography. Seventeen patients (85%) experienced a 50% or more recovery rate as calculated using the Hirabayashi formula during the follow-up period (mean 32.5 months), despite a persistently narrow spinal canal and permanent or increased intramedullary high-intensity signal after surgery.

Conclusions

Results of the study showed that patients with CCM benefited from anterior cervical discectomy and fusion with instrumentation or cervical corpectomy and fusion with instrumentation procedures despite insufficient decompression of the spinal canal. Fusion of the affected level(s) might be the reason for the acquired high recovery rates. The authors also conclude that the neurological improvement is not correlated with the reversal of or decrease in the intramedullary high-intensity signal change after surgery.
Log-rolling technique producing unacceptable motion during body position changes in patients with traumatic spinal cord injury
Authors: Conrad Bryan P. , Horodyski MaryBeth , Wright John , Ruetz Phyllis , Rechtine Glenn R.
Published: July 2008

Object

The purpose of the present study was to compare spinal motion generated during log-rolling and kinetic therapy with that generated when using a kinetic treatment table (KTT). The authors' hypothesis was that the KTT would produce less spinal motion while maintaining the benefits of body position changes.

Methods

Cervical and lumbar instability was created in three fresh, unembalmed cadavers. Electromagnetic sensors were fixed to the C5–6 and T12–L2 segments to measure cervical and lumbar spine segmental motion. Body position changes were performed using the traditional log-roll method and a KTT. Spinal motion was measured during each maneuver.

Turning the cadaveric specimens on the KTT bed caused significantly less cervical motion than the log-roll technique as measured in flexion and axial rotation. The log-roll technique caused significantly greater cervical motion during body position changes than turning using the KTT.

Conclusions

Although the global instability will require surgical stabilization, consideration should be given to initial immobilization on a KTT to decrease the likelihood of secondary injury.
Chylorrhea: a rare complication of thoracoscopic discectomy of the thoracolumbar junction
Authors: Amini Amin , Apfelbaum Ronald I. , Schmidt Meic H.
Published: July 2008

✓The thoracic duct along with the cisterna chyli is a major lymphatic pathway near the anterior thoracolumbar spine. Despite the fragile nature of the lymphatic system and its proximity to the spinal column, chylorrhea is rarely encountered by spine surgeons. The authors present a unique case of chylorrhea associated with a left thoracoscopic, trans-diaphragmatic discectomy and fusion for a T12–L1 herniated disc. The anomalous location of the thoracic duct at the left lateral vertebral column contributes to this unusual complication.
Thioredoxin‐Like [2Fe–2S] Ferredoxin
Authors: Meyer Jacques , Andrade Susana LA , Einsle Oliver
Published: June 2008

Thioredoxin‐like [2Fe–2S] ferredoxin (Trx‐like‐Fd) is a soluble homodimer of ca. 100‐residue subunits, each containing a [2Fe–2S] cluster. This cluster is redox active and shuttles between the diferric [2Fe–2S]2+and the ferric–ferrous mixed‐valence [2Fe–2S]+state. The four cysteine ligands of the cluster occur in an idiosyncratic Cys‐X10, 12‐Cys‐X29, 34‐Cys‐X3‐Cys pattern. The small size of this protein and the tight insertion of the Fe–S cluster within the protein framework suggest an electron transfer function. However, the dimeric structure and the presence of a protruding loop in the vicinity of the Fe–S cluster may be indicative of a regulatory function. Protein folds similar to the Trx‐like‐Fd monomer occur as domains or subunits in many redox enzymes. In these cases, a single copy of the polypeptide chain is present with anN‐terminal extension of ca. 100 residues, and the protruding loop is shorter or absent altogether. Trx‐like‐Fd has been studied in considerable detail by high‐resolution X‐ray crystallography, spectroscopy, and site‐directed mutagenesis. Its function, however, has so far remained unknown.
C
alx‐β Domains
Authors: Hilge Mark
Published: June 2008

Calx‐β domains that display the architecture of a seven‐stranded β‐sandwich form a relatively new class of Ca
2+
binding domains and are most closely related to C2 domains. Depending on the presence of a few acidic key residues in their Ca
2+
binding sites, Calx‐β domains can bind up to four Ca
2+
ions with affinities ranging from 10
−7
to 10
−4
 M. Functionally, the two copies of Calx‐β domains present in the cytosolic loop of the Na
+
/Ca
2+
exchanger are most extensively investigated and act as sensors for intracellular Ca
2+
. However, the physiological role of the vast majority of Calx‐β domains, located in the extracellular matrix, is intriguing since Ca
2+
concentrations in this environment are generally high.
TheMre11 Nuclease Complex
Authors: Hopfner Karl‐Peter , Bemeleit Derk , Lammens Katja
Published: June 2008

The repair of DNA double‐strand breaks (DSBs) is necessary to maintain genome stability and prevent cell aberration and cancer development. Meiotic recombination 11 (Mre11) and radiation sensitivity 50 (Rad50) form an evolutionary conserved complex (denoted Mre11 complex) that is a key factor in the detection, repair, and signaling of DSBs. The Mre11 complex possesses ATP‐stimulated DNA binding, DNA endo‐ and exonuclease activities as well as DNA cross‐linking functions. The Mre11 complex is a primary sensor for DNA DSBs and is involved in many aspects of the repair of and cellular response to DNA DSBs. Its activity is controlled by at least three different metal binding sites, a manganese‐dependent nuclease (Mre11 phosphodiesterase domain), a magnesium‐dependent ATPase (Rad50 ABC ATPase domain), and a zinc‐mediated DNA tethering function, located at the apex of a long Rad50 coiled‐coil domain. Although the mechanism remains to be shown, current structural and functional data indicate that the Mre11 complex is an ATP‐dependent cross‐linker and a processing factor for DNA ends.
VAP1—Snake Venom Homolog of MammalianADAMs
Authors: Takeda Soichi
Published: June 2008

Vascular‐apoptosis‐inducing protein‐1 (VAP1) is a zinc endopeptidase from western diamondback snakeCrotalus atroxvenom. VAP1 possesses a metalloproteinase/disintegrin/cysteine‐rich (MDC) domain that bears the typical domain architecture of the adamalysin/reprolysin/ADAM (a disintegrin and metalloproteinase) family of proteins. Mammalian ADAM proteinases are unique in that they have both proteolytic and adhesive properties. Additionally, as cell‐surface proteins, they constitute a major class of membrane‐anchored sheddases and participate in the processing of cell‐surface‐protein ectodomains, including the latent forms of growth factors, cytokines, and receptors. The crystal structures of VAP1 reveal a C‐shaped MDC domain architecture and a potential protein–protein interaction site in the C domain that faces the catalytic site in the M domain. The structures of VAP1 and related proteins suggest that there is interplay between proteolytic and adhesive functions in the proteinases of the adamalysin/reprolysin/ADAM family.
The Membrane‐Bound Nitrate Reductase
A
from Escherichia Coli:
Nar
GHI
Authors: Bertero Michela
Published: June 2008

The bacterium

Escherichia coli

is able to survive in a wide range of adverse environmental conditions. When oxygen is limited and nitrate is present,

E. coli

synthesizes a specific electron transfer chain to produce energy for its own survival. The chain is constituted by two membrane‐bound enzymes: the initial formate dehydrogenase FdnGHI and the terminal nitrate reductase NarGHI. Electrons are transferred from the formate oxidation site to the nitrate reduction site with a net translocation of protons across the cytoplasmic membrane. In the recent years, crystallographic studies have shed light on the structure and function of the two enzymes revealing a clear picture of the nitrate electron transfer chain at the atomic level. The present article focuses on the advances obtained on NarGHI, its function and architecture, and the eight redox cofactors that form like an electrical wire through all the enzymes, starting from the electron acceptor site to the catalytic center.
Sustainable Groundwater Management
Authors: Brunner Philip , Kinzelbach Wolfgang
Published: June 2008

The pressure on global water resources is increasing continuously, and the need for sustainable groundwater management practices has never been greater than now. First formulations of sustainable aquifer management were published as early as 1915, and since then, the attention given to this subject has been growing. However, the huge number of different approaches describing what sustainable water management is, suggests that it is practically impossible to provide a definition general enough to cover all the different systems and at the same time concrete enough to offer useful advice to the stakeholders and decision makers involved. In this article, a short overview of the development of the termsustainabilityin the context of aquifer management is discussed and put into context with the physical features of aquifers. Considering the difficulties that arise in finding a universally applicable definition of sustainability, identifying nonsustainable practices to be avoided and developing a suitable working methodology in a basin‐wide context is a more efficient approach. To illustrate the consequences of nonsustainable practices, some of the most prominent groundwater‐related sustainability issues are briefly discussed—the overpumping of aquifers, the destruction of wetlands, salinization of soils and water resources, as well as the contamination of aquifers with persistent pollutants, such as salt or chlorinated hydrocarbons. Finally, the role of numerical modeling as a tool to develop sustainable management practices is analyzed, and a case study is presented to provide an example of a suitable working methodology within a specific project area.
Consolidation of Soils
Authors: Verruijt Arnold
Published: June 2008

The theory of consolidation is of major interest in the analysis of deformations of porous media, in soil and rock mechanics, in nonsteady groundwater movement, and in the subsidence due to groundwater recovery and due to the depletion of reservoirs of gas or oil. In this article, the basic theory of consolidation is presented, and the theory is illustrated by some examples. The examples are taken from the fields of elementary soil mechanics, nonsteady groundwater flow and the production of gas from a deep reservoir. The examples chosen all admit a relatively simple analytical solution, using integral transformation methods.
Gold in Homogeneous Catalysis
Authors: Jiménez‐Núñez Eloása , Echavarren Antonio M.
Published: June 2008

The important types of transformations catalyzed by homogeneous Au(I) and Au(III) complexes or salts are reviewed. The reactions are organized mechanistically on the basis of the main functional group being activated by the gold catalyst. Particular emphasis is given on the most general reactions for the formation of CC bonds.
N

‐Heterocyclic Carbene‐Containing Metal Complexes
Authors: Fantasia Serena , Clavier Hervé , Nolan Steven P.
Published: June 2008

In the last decade, coordination chemistry has witnessed the advent of a new class of ligands: the
N
‐heterocyclic carbenes (NHCs). The “success story” associated with this ligand family can be explained by the unique stereoelectronic properties of the NHCs; these unique properties have led to their numerous applications in catalysis. This article provides an overview of developments and recent advances in the syntheses of NHCs and NHCtransition metal complexes. For these NHC ligand‐containing complexes, an analysis focuses on stability and reactivity patterns is provided. Reactions such as the cleavage of NHCmetal bond, CH and CC activations, NHC migration, and NHC insertion are presented.
Fear‐Potentiated Startle and Light‐Enhanced Startle Models in Drug Discovery
Authors: Groenink Lucianne , Bijlsma Elisabeth Y. , Olivier Berend
Published: June 2008

Described in this unit are the fear‐potentiated startle (FPS) and light‐enhanced startle (LES) tests. These protocols have proven reliable in detecting the anxiolytic properties of test compounds. The principle of these tests is that the magnitude of the acoustic startle reflex is an index of anxiety. The FPS test includes two training sessions in which an intrinsically aversive foot shock is paired with a neutral cue light. In the test session presentation of this cue light is subsequently used to elicit startle potentiation. In the LES test startle reactivity is increased by presentation of bright light. Because LES is based on the innate aversion of rodents for bright light it does not require training sessions. Although LES has been used less frequently than FPS for screening compounds, it has an advantage in that drug effects on startle potentiation are independent of memory retrieval. Further, the contextual anxiety measured in the LES test could be more relevant for pathological anxiety than the conditioned fear associated with the FPS test. Curr. Protoc. Pharmacol. 41:5.48.1‐5.48.15. © 2008 by John Wiley & Sons, Inc.
The Ussing Chamber and Measurement of Drug Actions on Mucosal Ion Transport
Authors: Brown David R. , O’Grady Scott M.
Published: June 2008

Ussing chamber technology can be used to investigate the pharmacodynamic and pharmacokinetic properties of drugs and natural substances on polarized epithelia. With this approach, epithelial sheets or confluent epithelial cell monolayers are mounted between two half‐chambers, permitting compound delivery to either the apical or basolateral cell surface. Described in this unit are protocols for determining the effects of test compounds on transepithelial ion transport processes. Curr. Protoc. Pharmacol. 41:7.12.1‐7.12.17. © 2008 by John Wiley & Sons, Inc.
Drug Testing in Cellular Chemotaxis Assays
Authors: Mellado Mario , Martínez‐A Carlos , Rodríguez‐Frade José Miguel
Published: June 2008

Described in this unit are methods for measuring the cell migration process. While cell adhesion protocols allow study of migrating cell interactions with the endothelial matrix, cellular migration assays permit analysis of directed cell movement towards a chemotactic gradient, both in vivo and in vitro. An in vitro cell invasion protocol is provided for analysis of the sum of the cell adhesion, migration, and invasion activities involved in tumor cell motility. Curr. Protoc. Pharmacol. 41:12.11.1‐12.11.22. © 2008 by John Wiley & Sons, Inc.
Matrix‐Assisted Laser Desorption/Ionization Time‐of‐Flight Mass Spectrometry of Oligonucleotides
Authors: Castleberry Colette M. , Chou Chau‐Wen , Limbach Patrick A.
Published: June 2008

MALDI‐MS is one of the most useful techniques available for determining biomolecule mass. It offers high mass accuracy, good sensitivity, simplicity, and speed. Because singly charged ions of oligonucleotides are typically observed, MALDI‐MS spectra are easy to interpret. This unit presents protocols for sample preparation and purification, matrix preparation, and matrix/analyte sample preparation. It provides an introduction to the instrumentation and its calibration, and a discussion of some of the useful applications of MALDI‐MS analysis in the study of oligonucleotides. This technique is typically used for 120‐mer or smaller oligonucleotides. Curr. Protoc. Nucleic Acid Chem. 33:10.1.1‐10.1.21. © 2008 by John Wiley & Sons, Inc.
Solid‐Supported Diphosphitylating and Triphosphitylating Reagents for Nucleoside Modification
Authors: Ahmadibeni Yousef , Parang Keykavous
Published: June 2008

This unit describes procedures for synthesis of diphosphitylating and triphosphitylating reagents. The synthesized reagents are first immobilized on appropriate polymer‐bound linkers. Rigid and sterically hindered polymer‐bound diphosphitylating and triphosphitylating reagents are then reacted selectively with the 5′‐hydroxyl group of nucleosides in the presence of excess nucleosides. Typical oxidation with tert‐butyl hydroperoxide, deprotection, and final cleavage of the products from the resins using a trifluoroacetic acid cocktail afford various nucleoside 5′‐O‐diphosphate and nucleoside 5′‐O‐triphosphate analogs. The use of the diphosphitylating and polymer‐bound diphosphitylating reagents in preparation of oligodeoxynucleotides containing diphosphodiester internucleotide bridges is also described. This solid‐phase strategy allows for the synthesis of the phosphorylated compounds without the need for nucleoside phosphate precursors, protected nucleosides, or purification of intermediates. Curr. Protoc. Nucleic Acid Chem. 33:13.8.1‐13.8.29. © 2008 by John Wiley & Sons, Inc.
Head and Neck MRA at 3.0T
Authors: Bernstein Matt A. , Huston John
Published: June 2008

3.0T MRI scanners are becoming more widely used in clinical practice, particularly for neurological applications. The increased signal‐to‐noise ratio (SNR) provided by 3.0T compared to 1.5T is particularly useful for applications like magnetic resonance angiography (MRA). A protocol to image the intracranial circulation with 3‐D time of flight (3DTOF), and a protocol to image the carotid, vertebral, and basilar arteries with contrast‐enhanced MRA are presented. The increased SNR at 3.0T is used to increase the spatial resolution. For the 3DTOF exam, the acquisition time is also reduced with the use of parallel imaging.
Coronary MRA
Authors: Deshpande Vibhas S. , Li Debiao
Published: June 2008

Coronary X‐ray angiography is the gold standard for coronary artery imaging, but is an invasive procedure, with a minor risk of potentially serious complications in addition to the drawback of exposure to ionizing radiation. Coronary magnetic resonance angiography (MRA) is a noninvasive method of imaging the coronary arteries, with no known adverse effects. In addition to morphologic evaluation of coronary artery disease with coronary MRA, cardiac MRI offers exciting possibilities to study the functional significance of coronary artery disease in the same setting. Three widely used coronary MRA approaches are presented‐‐two free‐breathing navigator‐gated methods, and a breath‐hold method. Although the positive predictive value of coronary MRA for detecting stenoses remains lower than that of X‐ray angiography, coronary MRA can reliably detect anomalous origins of coronary arteries, and has a high negative predictive value for stenoses. In conclusion, coronary MRA is a promising tool to study coronary artery disease.
MR Imaging of the Midfoot and Forefoot
Authors: Bencardino Jenny , Rosenberg Zehava S.
Published: June 2008

MR imaging is the diagnostic modality of choice for the evaluation of traumatic, inflammatory and neoplastic processes affecting the midfoot and forefoot soft tissue structures including muscles, ligaments, and tendons. MR imaging is also valuable in the diagnosis of occult bony trauma, stress reaction or fractures, and osteomyelitis. Exquisite contrast resolution, noninvasiveness, and multiplanar capabilities are unique features that make MR imaging a powerful diagnostic technique. The authors employ a basic protocol using T1‐weighted, fast spin echo proton density with and without frequency‐selective fat saturation, and fast spin echo T2‐weighted sequences as well as short‐tau inversion recovery (STIR) imaging. Additional imaging following intravenous gadolinium administration is indicated when osteomyelitis and neoplastic processes are suspected. Post‐contrast fat‐suppressed T1‐weighted sequences are necessary if intravenous or intra‐articular gadolinium is utilized.
Isolation of Microtubules and Microtubule Proteins
Authors: Avila J. , Soares H. , Fanarraga M.L. , Zabala J.C.
Published: June 2008

This unit describes various protocols for the isolation and purification of the main constituents of microtubules, chiefly α‐ and β‐tubulin, and the most significant microtubule associated proteins (MAPs), specifically MAP1A, MAP1B, MAP2, and tau. We include a classical isolation method for soluble tubulin heterodimer as the first basic purification protocol. In addition, we show how to analyze the tubulin and MAPs obtained after a phosphocellulose chromatography purification procedure. This unit also details a powerful and simple method to determine the native state of the purified tubulin based on one‐dimensional electrophoresis under nondenaturing conditions (UNIT 6.5). The last protocol describes the application of a new technique that allows visualizing the quality of polymerized microtubules based on atomic force microscopy (AFM). Curr. Protoc. Cell Biol. 39:3.29.1‐3.29.28. © 2008 by John Wiley & Sons, Inc.
Quantitative Colocalization Analysis of Confocal Fluorescence Microscopy Images
Authors: Zinchuk Vadim , Zinchuk Olga
Published: June 2008

Colocalization is an important finding in many cell biological studies. This unit describes a protocol for quantitative evaluation of images with colocalization based on the calculation of a number of specialized coefficients. First, images of double‐stained sections are subjected to background correction. Then, various coefficients are calculated. Meanings of the coefficients and a guide to interpretation of their results indicating either presence or absence of colocalization are given. Success in colocalization studies depends on the quality of analyzed images, proper preparation of them for coefficients calculations, and correct interpretation of obtained results. This protocol helps to ensure reliability of colocalization coefficients calculations. Curr. Protoc. Cell Biol. 39:4.19.1‐4.19.16. © 2008 by John Wiley & Sons, Inc.
Assays for Ribosomal RNA Processing and Ribosome Assembly
Authors: Pestov Dimitri G. , Lapik Yevgeniya R. , Lau Lester F.
Published: June 2008

The synthesis of ribosomes is a major metabolic activity critical for cell growth and homeostasis. Understanding the mechanisms of ribosome biogenesis has important implications for studying both protein synthesis and cell cycle control. This unit describes several techniques for the analysis of rRNA maturation and ribosome assembly adapted for mammalian cells. Metabolic labeling of rRNA and hybridization analysis of precursors can be used to assess changes in rRNA processing that occur under experimental conditions of interest. Separation of preribosomal particles by sucrose gradient centrifugation is suitable for the analysis of proteins associated with preribosomes during their assembly and maturation in the cell nucleus. Curr. Protoc. Cell Biol. 39:22.11.1‐22.11.16. © 2008 by John Wiley & Sons, Inc.
Using GenePattern for Gene Expression Analysis
Authors: Kuehn Heidi , Liberzon Arthur , Reich Michael , Mesirov Jill P.
Published: June 2008

The abundance of genomic data now available in biomedical research has stimulated the development of sophisticated statistical methods for interpreting the data, and of special visualization tools for displaying the results in a concise and meaningful manner. However, biologists often find these methods and tools difficult to understand and use correctly. GenePattern is a freely available software package that addresses this issue by providing more than 100 analysis and visualization tools for genomic research in a comprehensive user‐friendly environment for users at all levels of computational experience and sophistication. This unit demonstrates how to prepare and analyze microarray data in GenePattern. Curr. Protoc. Bioinform. 22:7.12.1–7.12.39. © 2008 by John Wiley & Sons, Inc.
Prediction of Protein‐Protein Interaction Networks
Authors: Gomez Shawn M. , Choi Kwangbom , Wu Yang
Published: June 2008

This unit offers a general overview of several techniques that have been developed for inferring functional and/or protein‐protein interaction networks. The majority of these use whole‐genome sequences as their primary input source of data. In addition, a few methods that utilize both protein features and experimental protein‐protein interaction data directly in the prediction of new interactions have recently been developed. While an exhaustive list of approaches is not presented, it is hoped that the reader will gain a sense of how these approaches are implemented and an idea of their relative strengths and weaknesses, and a broader perspective on the type of work being conducted in this highly active area of research. Curr. Protoc. Bioinform. 22:8.2.1–8.2.14. © 2008 by John Wiley & Sons, Inc.
Searching the MINT Database for Protein Interaction Information
Authors: Cesareni Gianni , Chatr‐aryamontri Andrew , Licata Luana , Ceol Arnaud
Published: June 2008

The Molecular Interactions Database (MINT) is a relational database designed to store information about protein interactions. Expert curators extract the relevant information from the scientific literature and deposit it in a computer readable form. Currently (April 2008), MINT contains information on almost 29,000 proteins and more than 100,000 interactions from more than 30 model organisms. This unit provides protocols for searching MINT over the Internet, using the MINT Viewer. Curr. Protoc. Bioinform. 22:8.5.1–8.5.13. © 2008 by John Wiley & Sons, Inc.
Using ChemBank to Probe Chemical Biology
Authors: Petri Seiler Kathleen , Kuehn Heidi , Pat Happ Mary , DeCaprio Dave , Clemons Paul A.
Published: June 2008

ChemBank (http://chembank.broad.harvard.edu/) is a public, Web‐based informatics environment. ChemBank stores and makes freely available data derived from small molecules and small‐molecule screens and has resources for relating and studying these data. Currently, ChemBank stores information on hundreds of thousands of small molecules and hundreds of biomedically relevant assays performed at the Broad Institute screening center. Web‐based analysis tools are available within ChemBank to study the relationships between small molecules, cell measurements, and cell states. This unit demonstrates the use of ChemBank data to ask and answer questions relating to chemical biology and screening experiments contained within ChemBank. Curr. Protoc. Bioinform. 22:14.5.1–14.5.26. © 2008 by John Wiley & Sons, Inc.
The Synthesis of Phenols and Quinones viaFischer Carbene Complexes
Authors: Waters Marcey L. , Wulff William D.
Published: June 2008

Fischer carbene complexes can be broadly defined as those transition‐metal carbene complexes that have a low oxidation state, have an electrophilic carbene carbon , and usually have a heteroatom‐stabilizing substituent on the carbene carbon. Fischer complexes were the first examples of any type of transition metal carbene complexes to be reported. The reaction of Fischer carbene complexes with alkynes is facile, occurring just above ambient temperature, and resulting in the assembly of a benzene ring from the three carbons of the alpha, beta‐unsaturated carbine complex, the two carbons of the alkyne, and the carbon of a carbon monoxide ligand. The synthetic value of this reaction stems from its broad scope, the generally high yields for the process, and the fact that that the products can function as intermediates for the synthesis of a variety of aromatic compounds includingpara‐quinones. It is the most synthetically valuable of the large number of Fischer carbene complexes that have been developed for applications in synthetic organic chemistry. This chapter is the first comprehensive review that is limited to the synthesis of phenols and quinones from the reactions of Fischer carbene complexes with alkynes.
Literature Searching Methodology
Authors: Roth Dana L.
Published: June 2008

Descriptions of analytical methods and instrumental techniques are found in an astonishing variety of resources. Because of this wide variety of sources and the extensive time period over which they have been published, developing an effective literature searching methodology is absolutely essential for students, research faculty, and practicing chemists. This article covers traditional methodologies and basic resources. In addition, recent widespread adoption of electronic journals and reference works, plus the virtually universal adoption of Google searching, are substantially transforming literature searching methodology.