bluuebunny/crossref_metadata_2025 huggingface dataset:
Ability and Performance on Ill-Structured Problems: The Substitution Effect of Inductive Reasoning Ability
Authors: Bradley Wray E.
Published: March 2009

ABSTRACT: Some cognitive abilities may act as partial substitutes for experience. These abilities have the potential to enhance the performance of inexperienced professionals by helping them synthesize and make better use of limited domain or task-specific experience. This study investigates the substitution effect of inductive reasoning ability. An experiment required 130 practicing business valuation professionals (91 are CPAs) to solve an ill-structured business valuation case. The results of the experiment show that the worst performance came from inexperienced professionals who had low inductive reasoning ability. However, the performance of inexperienced professionals with high inductive reasoning ability was similar to the performance of more experienced professionals. This suggests that high inductive reasoning ability acted as a partial substitute for experience. The practical importance of this substitution effect is that training in inductive reasoning has the potential to increase the performance of inexperienced accounting professionals who encounter ill-structured problems or tasks. Accounting students would also benefit from training in inductive reasoning. Suggested future research is discussed.
Diffuse Lung Disease in Infancy: A Proposed Classification Applied to 259 Diagnostic Biopsies
Authors: Langston Claire , Dishop Megan K.
Published: March 2009

Thoracoscopic and open lung biopsies are being performed with increasing frequency in neonates and infants and are an important component of the diagnostic evaluation of respiratory compromise in these very young children. Diffuse lung disease in infancy includes a wide spectrum of developmental, genetic, inflammatory, infectious, and reactive disorders. The majority of the entities diagnosed in infancy (68%) in this retrospective lung biopsy series are seen almost exclusively in this age group and not in older children and adults. These include primary disorders of pulmonary and pulmonary vascular development, secondary disorders affecting prenatal and/ or postnatal lung growth, genetic disorders of surfactant function, pulmonary interstitial glycogenosis, and neuroendocrine cell hyperplasia of infancy. Although the diagnostic approach to infant lung biopsies is guided primarily by the clinical history and imaging findings, all cases require careful assessment of alveolar growth, vascular architecture, interstitial cellularity, and histologic patterns associated with genetic abnormalities of surfactant metabolism. Recognition of one or more of these processes assists not only in treatment planning but also in further diagnostic evaluation and prognostication and may have implications for subsequent siblings and other family members. In this study, we have applied a classification system developed by a North American multicenter multidisciplinary group to lung biopsies seen at our institution and have used this material to describe and illustrate the spectrum of diffuse lung disease in infancy.
Outcomes of Chronic Insertional Achilles Tendinosis Using FHL Autograft Through Single Incision
Authors: Elias Ilan , Raikin Steven M. , Besser Marcus P. , Nazarian Levon N.
Published: March 2009

Background: The purpose of this study was to evaluate the clinical outcomes and objective isokinetic dynamometry on a cohort of patients with chronic insertional Achilles tendinosis, who underwent surgical reconstruction using an FHL tendon autograft transfer through a single incision. Materials and Methods: Forty patients (16 male and 24 female; mean age, 57 years; age range, 39 to 76 years) with persistent chronic Achilles tendinosis were evaluated after surgical reconstruction at an average of 27 months after surgery. At the time of final followup, ankle strength and active range of motion (AROM) were evaluated using Biodex® isokinetic dynamometry. Additionally, patients were assessed with AOFAS Ankle Hindfoot scores, pain on a Visual Analog Scale (VAS) and their self-reported level of satisfaction (Very Good, Good, Fair, Poor). Results: We found no loss of plantarflexion strength or plantarflexion power in the operated ankles; an average of 4-degree loss of AROM was found. The study population scored an average of 96/100 for the total AOFAS-AH score post-repair. The average VAS decreased from 7.5 pre-op to 0.3 post-op. Thirty-eight of 40 patients (95%) were satisfied with their outcome (rated Very Good or Good), two patients rated their outcome as Fair and none as Poor. Conclusion: For individuals with chronic insertional Achilles tendinosis, operative repair using an FHL tendon with the single-incision technique achieved a high percentage of satisfactory results as well as excellent functional and clinical outcomes including significant pain reduction.

Level of Evidence: IV, Retrospective Case Study
Arthroscopic Repair of Chronic Lateral Ankle Instability
Authors: Nuno M. Corte-Real , Moreira Rodrigo M.
Published: March 2009

Background: The current “gold standard” for treatment of chronic lateral ankle instability is the Broström-Gould procedure. Most authors recommend this type of operation even after an arthroscopic inspection of the joint. We review our results with an arthroscopic method of lateral ankle ligament repair. Materials and Methods: A method of arthroscopic lateral ligament repair with an anchor placed in the fibula is described. We used this technique on 31 consecutive patients (28 were available for followup). Twenty-one patients had work or traffic accidents, four suffered casual falls. and three had sport-related lesions. The patients were evaluated after 24.5 month average followup. Results: The average postoperative AOFAS score was 85.3 (82.3 in the workers-compensation group and 94.4 in the others) and average satisfaction was 3.8 (3.5 to workers-compensation and 4.6 for the others). Complications occurred in nine patients (29%), but only three cases had ongoing problems. We had two recurrences (another sprain without instability on the stress radiograph). Three patients had some wound healing problems and three had injuries of the superficial peroneal nerve, one of which is persistent. One patient developed a deep venous thrombosis postoperatively. Conclusion: With this method, we achieved good clinical results. We had several complications but most of them were minor. It was a simple procedure with less morbidity to most patients. We believe it produced an anatomical repair of the lateral ligament with clinical and functional results similar to other techniques.

Level of Evidence: IV, Retrospective Case Study
Prognostic Value of Four Classifications of Calcaneal Fractures
Authors: Rubino Raffaele , Valderrabano Victor , Martin Sutter Paul , Regazzoni Pietro
Published: March 2009

Background: The purpose of this study was to assist surgeons treating calcaneal fractures in choosing the most predictive fracture classification and clinical outcome tool. Materials and Methods: For 152 patients (189 calcaneal fractures; average followup, 9.9 years), all fractures were classified in accordance with the Essex-Lopresti, OTA, Regazzoni, and Sanders classifications and matched with the following scores: AOFAS score, CNHF, FOA, MFS, Rowe, MFA, SF-36, and VAS. Results: The Essex-Lopresti classification showed no statistically significant relation with any of the clinical scores ( p <0.05). The OTA classification related statistically significant with the MFS ( p = 0.006), AOFAS score ( p = 0.013), FOA ( p = 0.019), Rowe ( p = 0.0027), and MFA score ( p = 0.03). The Regazzoni classification correlated with the AOFAS score ( p = 0.003), MFS ( p = 0.002), Rowe ( p = 0.002), CNHF ( p = 0.0001), FOA ( p = 0.003), MFA score ( p = 0.002), and VAS ( p = 0.005). The Sanders classification corrrelated with the AOFAS score ( p = 0.007), MFS ( p = 0.001), Rowe ( p = 0.001), CNHF ( p = 0.024), FOA ( p = 0.021), MFA score ( p = 0.036), and VAS ( p = 0.014). Conclusion: Compared to radiological based classifications, the CT based classifications, especially the Regazzoni and Sanders classifications, exhibited higher prognostic value compared to ultimate outcome scores.

Level of Evidence: IV, Retrospective Case Series
Tibial Nerve Palsy Associated with Lateralizing Calcaneal Osteotomy: Case Reviews and Technical Tip
Authors: Krause Fabian G. , Pohl Margy J. , Penner Murray J. , Younger Alastair SE
Published: March 2009

Level of Evidence: V, Expert Opinion
Two-Dimensional Navigation for Improved Entry Portal Placement in Tibiotalocalcaneal Arthrodesis with Retrograde Nails
Authors: Mückley Thomas , Klos Kajetan , Müller Matthias , Tiemann Andreas , Hofmann Gunther O.
Published: March 2009

Level of Evidence: V, Expert Opinion
Diagnosis and treatment of pudendal nerve entrapment syndrome subtypes: imaging, injections, and minimal access surgery
Authors: Filler Aaron G.
Published: March 2009

Object

To improve diagnostic accuracy and achieve high levels of treatment success in patients with pudendal nerve entrapment (PNE) syndromes, the author of this study applied advanced technology diagnostics in distinguishing the various syndrome types according to the different entrapment locations and evaluated new minimal access surgical techniques to treat each subtype.

Methods

Two hundred cases were prospectively evaluated using a standardized set of patient-completed functional and symptom assessments, a collection of new physical examination maneuvers, MR neurography, open MR image–guided injections, intraoperative neurophysiology, minimal access surgery, and formal outcome assessment with the Oswestry Disability Index, pain diagrams, and analog pain scales.

Results

Four primary types of PNE syndromes were identified based on the different locations of entrapment: Type I, entrapment at the exit of the greater sciatic notch in concert with piriformis muscle spasm; Type II, entrapment at the level of the ischial spine, sacrotuberous ligament, and lesser sciatic notch entrance; Type III, entrapment in association with obturator internus muscle spasm at the entrance of the Alcock canal; and Type IV, distal entrapment of terminal branches. The application of new, targeted minimal access surgical techniques led to sustained good to excellent outcomes (50–100% improvement in the pain score or functional score) in 87% of patients. Most of these patients obtained most of their improvement within 4 weeks of surgery, although some continued to experience progressive improvements up to 12 months after surgery.

Conclusions

The application of advanced diagnostics to categorize PNE syndrome origins into 4 major subtypes and the subsequent treatment of each subtype with a tailored strategy greatly improved therapeutic outcomes as compared with those reported when only a single treatment paradigm was applied to all patients.
The impact of parametric uncertainty and topographic error in ice-sheet modelling
Authors: Hebeler Felix , Purves Ross S. , Jamieson Stewart S.R.
Published: March 2009

Ice-sheet models (ISMs) developed to simulate the behaviour of continental-scale ice sheets under past, present or future climate scenarios are subject to a number of uncertainties from various sources. These sources include the conceptualization of the ISM and the degree of abstraction and parameterizations of processes such as ice dynamics and mass balance. The assumption of spatially or temporally constant parameters (such as degree-day factor, atmospheric lapse rate or geothermal heat flux) is one example. Additionally, uncertainties in ISM input data such as topography or precipitation propagate to the model results. In order to assess and compare the impact of uncertainties from model parameters and climate on the GLIMMER ice-sheet model, a parametric uncertainty analysis (PUA) was conducted. Parameter variation was deduced from a suite of sensitivity tests, and accuracy information was deduced from input data and the literature. Recorded variation of modelled ice extent across the PUA runs was 65% for equilibrium ice sheets. Additionally, the susceptibility of ISM results to modelled uncertainty in input topography was assessed. Resulting variations in modelled ice extent in the range of 0.8–6.6% are comparable to that of ISM parameters such as flow enhancement, basal traction and geothermal heat flux.
Surging, accelerating surface lowering and volume reduction of the Malaspina Glacier system, Alaska, USA, and Yukon, Canada, from 1972 to 2006
Authors: Muskett Reginald R. , Lingle Craig S. , Sauber Jeanne M. , Post Austin S. , Tangborn Wendell V. , Rabus Bernard T.
Published: March 2009

Near-concurrent surges and multi-decadal surface-elevation changes on the Malaspina Glacier system Alaska, USA, and Yukon, Canada, were investigated using digital elevation models and laser altimetry from airborne and space-borne sensors. Surface-elevation changes on Seward Lobe in two time periods support a hypothesis of moraine folding by a mechanism of sequential surges alternating from southeast to south-southwest. The near-concurrent surges of Agassiz, Lower Seward and Marvine glaciers support a hypothesis of englacial water storage being a critical factor of surging. Acceleration of area-average surface lowering on the piedmont glaciers occurred, from 1.5 ± 0.1 m a−1 between 1972 and 1999 to 2.3 ± 0.3 m a−1 between 1999 and 2002. On the western half of Upper Seward Glacier, above 1600 m, acceleration of surface lowering occurred from 2000 to 2003 relative to that from 1976 to 2000, indicating an effect from the surge of Lower Seward Glacier. From 2003 to 2006, the rate of surface lowering on Upper Seward Glacier has moderated back to the pre-2000 rate, indicating a recovery of surface elevation following the surge. From 1972 to 2002, the Malaspina Glacier system lost 156 ± 19 km3 (ice equivalent) on an area of 3661 km2.
Iterative improvement of the shallow-ice approximation
Authors: Souček Ondřej , Martinec Zdeněk
Published: March 2009

We present a new algorithm for a fast iterative improvement of the shallow-ice approximation (SIA) for the modeling of glacier flow. Based on the traditional SIA scaling assumptions, the solution of the Stokes problem is found by an operator-splitting iterative technique. The SIA solution obtained in the first step is successively improved to obtain a higher-order approximation. Each iterative step has computational demands comparable to solving the SIA, which makes the algorithm substantially faster than other higher-order or full-Stokes solvers. The performance of the algorithm is tested on a model example taken from the ISMIP-HOM intercomparison project.
Temporal and spatial changes of Laika Glacier, Canadian Arctic, since 1959, inferred from satellite remote sensing and mass-balance modelling
Authors: Huss Matthias , Stöckli Reto , Kappenberger Giovanni , Blatter Heinz
Published: March 2009

The retreat of Laika Glacier (4.4 km2), part of a small ice cap situated on Coburg Island, Canadian Arctic Archipelago, is analyzed using field data, satellite remote sensing and mass-balance modelling. We present a methodology for merging various data types and numerical models and investigate the temporal and spatial changes of a remote glacier during the past five decades. A glacier mass-balance and surface-evolution model is run for the period 1959–2006, forced with in situ weather observations and climate re-analysis data (ERA-40, NARR). The model is calibrated using the ice-volume change observed between 1959 and 1971, and measured seasonal mass balances. Calculated glacier surface elevation is validated against ICESat GLAS altimeter data and ASTER-derived elevation. Landsatderived glacier outlines are used to validate calculated ice extent. The piedmont tongue of Laika Glacier has retreated considerably and is in a state of disintegration. The modelled glacier mass balance between 1959 and 2006 was −0.41 m w.e. a−1, on average. Model results indicate a significant trend towards higher mass-balance gradients. A complete wastage of Laika Glacier by 2100 is predicted by model runs based on climate scenarios.
Variations in snow surface properties at the snowpack-depth, the slope and the basin scale
Authors: Schweizer Jürg , Heilig Achim , Bellaire Sascha , Fierz Charles
Published: March 2009

Variations of snow surface and snowpack properties affect avalanche formation. In up to four north-facing slopes above the tree line near Davos, Switzerland, snow surface properties were characterized. Penetration resistance was measured with a snow micro-penetrometer. The sampling scheme was designed to allow a multi-scale approach covering the snowpack depth scale (0.5–5 m), the slope scale (5–100 m) and the basin scale (100–1000 m). Observations and measurements were compared to the data of a nearby automatic weather station (AWS). The AWS data were also used to model snow-cover stratigraphy and its evolution with the numerical snow-cover model SNOWPACK. Comparing the four slopes showed that surface properties observed manually were similar among the three slopes that were sheltered, and often different from the slope that was wind-exposed. However, the penetration resistance of the surface layer was in most cases significantly different among slopes, although most values were <0.1 N, indicating very low hardness. These seemingly contradictory results follow from the different measurement support of the two methods. It is presently unclear which amount of variation at a given scale is relevant for avalanche formation. The geostatistical analysis and an analysis aimed at identifying the causes of variability were not conclusive. No patterns emerged that would allow conclusions regarding the effect on avalanche formation. Finding the causes of variability seems to require high-resolution terrain and weather models that are presently not readily available.
Monitoring ice-capped active Volcán Villarrica, southern Chile, using terrestrial photography combined with automatic weather stations and global positioning systems
Authors: Rivera Andrés , Corripio Javier G. , Brock Ben , Clavero Jorge , Wendt Jens
Published: March 2009

Volcán Villarrica (39°25′12″ S, 71°56′27″ W; 2847 m a.s.l.) is an active ice-capped volcano located in the Chilean lake district. The surface energy balance and glacier frontal variations have been monitored for several years, using automatic weather stations and satellite imagery. In recent field campaigns, surface topography was measured using Javad GPS receivers. Daily changes in snow-, ice-and tephra-covered areas were recorded using an automatic digital camera installed on a rock outcrop. In spite of frequently damaging weather conditions, two series of consecutive images were obtained, in 2006 and 2007. These photographs were georeferenced to a resampled 90 m pixel size SRTM digital elevation model and the reflectance values normalized according to several geometric and atmospheric parameters. The resulting daily maps of surface albedo are used as input to a distributed glacier-melt model during a 12 day mid-summer period. The spatial pattern of cumulative melt is complex and controlled by the distribution of airfall and wind-blown tephra, with extremely high melt rates occurring downwind of the crater and exposed ash banks. The camera images are also used to visualize the pattern of glacier crevassing. The results demonstrate the value of terrestrial photography in understanding the energy and mass balance of the glacier, including the generation of meltwater, and the potential value of the technique for monitoring volcanic activity and potential hazards associated with ice–volcano interactions during eruptive activity.
Recent Advances in the Computational Discovery of Transcription Factor Binding Sites
Authors: Nguyen Tung T. , Androulakis Ioannis P.
Published: March 2009

The discovery of gene regulatory elements requires the synergism between computational and experimental techniques in order to reveal the underlying regulatory mechanisms that drive gene expression in response to external cues and signals. Utilizing the large amount of high-throughput experimental data, constantly growing in recent years, researchers have attempted to decipher the patterns which are hidden in the genomic sequences. These patterns, called motifs, are potential binding sites to transcription factors which are hypothesized to be the main regulators of the transcription process. Consequently, precise detection of these elements is required and thus a large number of computational approaches have been developed to support the de novo identification of TFBSs. Even though novel approaches are continuously proposed and almost all have reported some success in yeast and other lower organisms, in higher organisms the problem still remains a challenge. In this paper, we therefore review the recent developments in computational methods for transcription factor binding site prediction. We start with a brief review of the basic approaches for binding site representation and promoter identification, then discuss the techniques to locate physical TFBSs, identify functional binding sites using orthologous information, and infer functional TFBSs within some context defined by additional prior knowledge. Finally, we briefly explore the opportunities for expanding these approaches towards the computational identification of transcriptional regulatory networks.
Hydrogen as Future Energy Carrier: The ENEA Point of View on Technology and Application Prospects
Authors: Conte Mario , Di Mario Francesco , Iacobazzi Agostino , Mattucci Antonio , Moreno Angelo , Ronchetti Marina
Published: March 2009

Hydrogen and fuel cells should reduce costs and increase reliability and durability to compete in the energy market. A considerable long term effort is necessary for research, development and demonstration of adequate solutions; important programs in this sense are carried out in the main industrialized countries, with the involvement of many industries, research structures and stakeholders. In such framework a relevant role is played in Italy by ENEA (Italian Agency for New Technologies, Energy and Environment). In the paper the main aspects related to the possible hydrogen role in the future society are addressed, according to ENEA perspectives.
Molecular Pathogenesis of Alzheimer’s Disease: Reductionist versus Expansionist Approaches
Authors: Castellani Rudy  J. , Zhu Xiongwei , Lee Hyoung-Gon , Smith Mark  A. , Perry George
Published: March 2009

Alzheimer’s disease (AD) is characterized clinically by dementia and pathologically by two hallmark lesions, senile plaques and neurofibrillary tangles. About a quarter century ago these hallmark lesions were purified and their protein constituents identified, precipitating an avalanche of molecular studies as well as substantial optimism about successful therapeutic intervention. In 2009, we now have copious knowledge on the biochemical cascades that produce these proteins, the different modifications and forms in which these proteins exist, and the ability to selectively target these proteins for therapeutic intervention on an experimental basis. At the same time, there has been no discernible alteration in the natural course of AD in humans. While it may be that the complexity of AD will exceed our capacity to make significant treatment progress for decades or more, a paradigm shift from the reductionism that defines amyloid-β and tau hypotheses, to one that more accurately reflects the meaning of neuropathological changes, may be warranted. We and others have demonstrated that AD pathology is a manifestation of cellular adaptation, specifically as a defense against oxidative injury. As such, AD pathology is therefore a host response rather than a manifestation of cytotoxic protein injury, and is unlikely to be a fruitful target for therapeutic intervention. An “expansionist” view of the disease, we believe, with oxidative stress as a pleiotropic and upstream process, more aptly describes the relationship between various and numerous molecular alterations and clinical disease.
13C-NMR Data of Diterpenes Isolated from Aristolochia Species
Authors: Pacheco Alison Geraldo , Machado de Oliveira Patrícia , Piló-Veloso Dorila , Flávio de Carvalho Alcântara Antônio
Published: March 2009

The genus Aristolochia,an important source of physiologically active compounds that belong to different chemical classes, is the subject of research in numerous pharmacological and chemical studies. This genus contains a large number of terpenoid compounds, particularly diterpenes. This work presents a compilation of the 13C-NMR data of 57 diterpenoids described between 1981 and 2007 which were isolated from Aristolochia species. The compounds are arranged skeletonwise in each section, according to their structures, i.e., clerodane, labdane, and kaurane derivatives. A brief discussion on the 13C chemical shifts of these diterpenes is also included.
Automatic Exudate Detection from Non-dilated Diabetic Retinopathy Retinal Images Using Fuzzy C-means Clustering
Authors: Sopharak Akara , Uyyanonvara Bunyarit , Barman Sarah
Published: March 2009

Exudates are the primary sign of Diabetic Retinopathy. Early detection can potentially reduce the risk of blindness. An automatic method to detect exudates from low-contrast digital images of retinopathy patients with non-dilated pupils using a Fuzzy C-Means (FCM) clustering is proposed. Contrast enhancement preprocessing is applied before four features, namely intensity, standard deviation on intensity, hue and a number of edge pixels, are extracted to supply as input parameters to coarse segmentation using FCM clustering method. The first result is then fine-tuned with morphological techniques. The detection results are validated by comparing with expert ophthalmologists’ hand-drawn ground-truths. Sensitivity, specificity, positive predictive value (PPV), positive likelihood ratio (PLR) and accuracy are used to evaluate overall performance. It is found that the proposed method detects exudates successfully with sensitivity, specificity, PPV, PLR and accuracy of 87.28%, 99.24%, 42.77%, 224.26 and 99.11%, respectively.
Measurement and Evaluation of Finger Tapping Movements Using Log-linearized Gaussian Mixture Networks
Authors: Shima Keisuke , Tsuji Toshio , Kandori Akihiko , Yokoe Masaru , Sakoda Saburo
Published: March 2009

This paper proposes a method to quantitatively measure and evaluate finger tapping movements for the assessment of motor function using log-linearized Gaussian mixture networks (LLGMNs). First, finger tapping movements are measured using magnetic sensors, and eleven indices are computed for evaluation. After standardizing these indices based on those of normal subjects, they are input to LLGMNs to assess motor function. Then, motor ability is probabilistically discriminated to determine whether it is normal or not using a classifier combined with the output of multiple LLGMNs based on bagging and entropy. This paper reports on evaluation and discrimination experiments performed on finger tapping movements in 33 Parkinson’s disease (PD) patients and 32 normal elderly subjects. The results showed that the patients could be classified correctly in terms of their impairment status with a high degree of accuracy (average rate: 93:1 § 3:69%) using 12 LLGMNs, which was about 5% higher than the results obtained using a single LLGMN.
Climate Change and Air Pollution: Exploring the Synergies and Potential for Mitigation in Industrializing Countries
Authors: Moore Frances  C.
Published: March 2009

Air pollutants such as tropospheric ozone and black carbon (soot) also contribute to the greenhouse effect. Black carbon is thought to be the second or third most important anthropogenic contributor to global warming, while troposheric ozone is the fourth most important. Both are also major components of indoor and outdoor air pollution. This paper reviews the existing literature of the health, economic, and climatic impacts of tropospheric ozone and black carbon emissions, together with mitigation options. The local nature of many of the impacts, combined with their short atmospheric lifetime and the existence of cost-effective abatement technologies that are already widely deployed in developed countries means reducing these emissions provides a highly climatically-effective mitigation option that is also appropriate to the development strategy of industrializing countries.
Visual Attention and Hearing Loss: Past and Current Perspectives
Authors: Tharpe Anne Marie , Ashmead Daniel , Sladen Douglas P. , Ryan Hollea A.M. , Rothpletz Ann M.
Published: March 2009

Background: It is reasonable to expect that deaf individuals require the use of vision for purposes other than those needed by hearing persons. For example, without the use of hearing, one would need to scan the environment visually to determine if someone was approaching rather
than listening for footsteps or a name being called. Furthermore, these experiential differences could alter the development of neural organization of sensory systems of deaf persons. Purpose: To review the evidence-based literature in the area of visual attention and deafness with
an emphasis on a series of visual attention studies utilizing several paradigms including the Continuous Performance Task, the Letter Cancellation Task, the Flanker Task, and a self-designed task of target identification in the periphery under distracter and nondistracter conditions conducted
at Vanderbilt University. Research Design: Systematic review Results: Collectively, the Vanderbilt studies pointed to a compensatory role that the visual system plays for deaf individuals. Specifically, the visual system appears to play an important role in directing a deaf individual's
attention to the near visual periphery. Conclusions: Studies of visual attention in deaf individuals have been mixed in their conclusions about whether altered neural organization results in better or worse visual attention abilities by those who are deaf relative to those with normal
hearing. The notion of across-the-board deficits or enhancements in the visual function of deaf individuals is not supported by the literature, nor is there support for the idea that fundamental visual sensory abilities such as acuity or light detection differ between deaf and hearing persons.
Anatomical Organization of the Auditory Cortex
Authors: Hackett Troy A.
Published: March 2009

The identification of areas that contribute to auditory processing in the human cerebral cortex has been the subject of sporadic investigation for more than one century. Several anatomical schemas have been advanced, but a standard model has not been adopted by researchers in the field.
Most often, the results of functional imaging or electrophysiological studies involving auditory cortex are related to the cytoarchitectonic map of Brodmann (1909). Though useful as a guide and point of reference, this map has never been validated and appears to be incomplete. In recent years,
renewed interest in the organization of auditory cortex has fostered numerous comparative studies in humans, nonhuman primates, and other mammalian species. From these efforts, common features of structural and functional organization have begun to emerge from which a working model of human
auditory cortex can be derived. The results of those studies and the rudiments of the model are reviewed in this manuscript.
Significant Vestibular System Impairment Is Common in a Cohort of Elderly Patients Referred for Assessment of Falls Risk
Authors: Jacobson Gary P. , McCaslin Devin L. , Grantham Sarah L. , Piker Erin G.
Published: March 2009

Background: Falls in elderly patients are associated with morbidity, mortality, and cost to the health-care system. The development of falls risk assessment programs have represented a method of responding to what is known about injurious falls. The multidimensional assessments
involve the comparison against normative data of a patient's performance on metrics known to influence the likelihood of future falls. The factors assessed usually include falls and medication history, measures of mentation, depression, orthostatic hypotension, simple or choice reaction time,
gait stability, postural stability, and the integrity of the patient's vision, somesthetic, and vestibular senses. Purpose: This investigation was conducted to measure the proportion of patients referred for falls risk assessment who have evidence of vestibular system impairment. Research
Design: Qualitative, retrospective review of data collected from 2003 to 2007. Study Sample: The cohort was 185 consecutive patients referred for multidimensional assessments of falls risk. Data Collection and Analysis: Patients underwent quantitative assessments of peripheral
and central vestibular system function consisting of electro- or videonystagmography (i.e., ENG/VNG), and sinusoidal harmonic acceleration testing. Results of these tests were compared to normative data. Results: We found that 73% of the sample who underwent vestibular system assessment
had quantitative evidence of either peripheral or central vestibular system impairment. Conclusions: Our results suggest that quantitative assessments of the vestibulo-ocular reflex should be conducted on patients who are evaluated for falls risk. These examinations should include at
least caloric testing and, where available, rotational testing.
Sexual seasonal growth variation and reproduction biology of the rock pool prawn, Palaemon elegans (Decapoda: Palaemonidae) in the southern Black Sea
Authors: Bilgin Sabri , Ozen Ozcan , Samsun Osman
Published: March 2009

The seasonal growth pattern and reproductive biology of the rock pool prawn, Palaemon elegans, were studied in the southern Black Sea between February 2002 and January 2004. The seasonal von Bertalanffy growth parameters, computed from monthly length frequency distributions, were estimated as L∞ = 47.8 mm total length (TL), K = 1. 115 year-1 for females and as L∞ = 41.1 mm TL, K = 1.654 year-1 for males. The seasonal oscillation in growth rate for females (C = 0.904) was larger than it was for males (C = 0.586). The slowest period of growth corresponded to June in females and February in males. The size at sexual maturity for females (TL50) was estimated as 33.8 mm TL. Ovigerous females were recorded from March to August and juveniles appeared in the benthic population in August. The ovarian development of the rock pool prawn was most probably initiated by photoperiod, whereas embryo development was accelerated with increasing water temperatures.
Diet of Atlantic lizardfish, Synodus saurus (Linnaeus, 1758) (Pisces: Synodontidae) in the central Mediterranean Sea
Authors: Esposito Valentina , Battaglia Pietro , Castriota Luca , Finoia Maria Grazia , Scotti Gianfranco , Andaloro Franco
Published: March 2009

The diet composition of the Atlantic lizardfish Synodus saurus, caught on sandy bottoms of the north-western coast of Sicily (southern Tyrrhenian Sea) is described. The stomachs of 224 specimens (from 73 to 280 mm TL) were collected between June 2005 and May 2006. The analysis of stomach contents showed that this species is almost exclusively piscivorous. Unlike other benthic predators of the study area, it mainly feeds on pelagic school-forming fish, such as Clupeidae, Engraulidae and Myctophidae and juveniles of Sparidae and Centracanthidae, and benthic prey play a secondary role. The diet of S. saurus is related to the seasonal availability of resources, depending on the occurrence of juveniles of several species and on the migration of pelagic fishes in the study area. There were no significant changes in prey items between predator length groups, but a positive, significant linear relationship between prey size and predator size was recorded.
Structure and absolute growth of a population of Hippolyte inermis Leach 1815 (Decapoda: Caridea) from Zostera marina (L.) meadows (Malaga, southern Spain)
Authors: Manjón-Cabeza M. Eugenia , Cobos Vanesa , García Muñoz J. Enrique , García Raso J. Enrique
Published: March 2009

The Hippolyte inermis Leach 1815 population from Zostera marina beds in southern Spain showed two recruitment periods that occurred simultaneously for both sexes (from September to December and from April to June), in a size range between 1.67 and 1.90 mm carapace length, due to gonadal activity and eggs hatching in summer and winter. The estimated Von Bertalanffy parameters were used to determine absolute growth and showed that males live for around 8 months and females for around 12 months; consequently, four cohorts for males and 7 to 8 for females can coexist throughout the cycle. The sex ratio favours females throughout the entire life cycle. Data published on the reproductive biology of H. inermis support the idea that this is a protandric hermaphrodite species, though recent studies have revealed that there is no histological proof of hermaphroditic sexuality in adult specimens of this species. The results obtained here indicate that the Cañuelo Beach Hippolyte inermis population has a gonochoric structure. If H. inermis were to have hermaphroditic sexuality, the sex reversal of adult males would occur in a single moult in the size range between 2.42 and 3.22 mm. These new, secondary females would be incorporated into the primary female cohort at practically the same size, although they would be 0.12 to 5.20 months younger. Our results, compared with those from other population studies, suggest that this species has a highly plastic population structure, which seems to be determined by external factors and which varies between the protandric and gonochoric condition, depending on the conditions of the habitat.
Chemical bioactivity of sponges along an environmental gradient in a Mediterranean cave
Authors: Turon Xavier , Martí Ruth , Uriz Maria J.
Published: March 2009

The bioactivity of the most abundant sponges from three communities in a Mediterranean cave was assessed by Microtox® assay in two seasons, spring (June) and autumn (November). We quantified bioactivity as a proxy for the investment in production of biologically active substances, and we related sponge bioactivity to growth form, growth rates, and physical contacts of each species with other species. We established a threshold for classifying a species as bioactive based on a comparison between the results of the Microtox® and the sea urchin embryo toxicity bioassay. A total of 30 species were included in the study, of which 50% were bioactive in some community or season. Significant ecological (between communities) and seasonal variation in mean bioactivity was found. When sponge bioactivity was related to sponge growth shape, it was found that the encrusting species tended to be more toxic than the non-encrusting ones. There was a negative relationship between bioactivity and sponge growth, suggesting a trade-off in energy allocation to defence and to other biological functions. Furthermore, a negative correlation was found between bioactivity and positive associations with other species. These results highlight the important role of chemically-mediated interactions in cave communities.
Two new polychaete species living in the mantle cavity of Calyptogena gallardoi (Bivalvia: Vesicomyidae) at a methane seep site off central Chile (~36°S)
Authors: Quiroga Eduardo , Sellanes Javier
Published: March 2009

Two new polychaete species belonging to Nautiliniellidae and Antonbruunidae were found in the mantle cavity of the vesicomyid bivalve Calyptogena gallardoi Sellanes and Krylova, 2005, at a methane seep site off central Chile. Shinkai robusta n. sp. is characterized by having modified parapodia with robust notopodia and nine simple hooks per parapodium on the middle setigers, and an anteriorly truncated sub-triangular prostomium, with a pair of small cirriform antennae. The new species closely resembles Shinkai longipedata Miura and Ohta, 1991, and Shinkai semilonga Miura and Hashimoto, 1996. Antonbruunia gerdesi n. sp. is characterized by having a trapezoidal prostomium, with five sub-equal occipital antennae and a conspicuous pygidium with two short, well-developed digitiform anal cirri. These two new species constitute the first report of polychaetes living in symbiosis with chemosymbiotic bivalves in the south-eastern Pacific.
Cyclic Nucleotide‐gated Ion Channels
Authors: Zheng Jie , Matulef Kimberly
Published: March 2009

Cyclic nucleotide‐gated (CNG) ion channels are activated by cAMP or cGMP, crucial intracellular messenger molecules that regulate a wide variety of physiological activities. In photoreceptors and olfactory neurons, CNG channels play an essential role in transducing sensory stimuli into electrical and chemical responses. CNG channels are also found in other tissues including brain and sperm, where they may contribute to physiological functions including pacemaking, synaptic transmission and chemosensation. The exquisite regulation of different CNG channels by divalent cations, calmodulin, phosphorylation and phospholipids allows these proteins to carry out disparate physiological functions with high precision. Our understanding of the structure of these channels has been greatly enhanced by the recent determination of the structures of domains of related ion channels. The powerful combination of electrophysiology, biochemistry, patch‐clamp fluorometry and X‐ray crystallography has begun to unravel the mystery of how CNG channels are regulated and how the binding of cyclic nucleotides lead to channel opening.

Key concepts

Ion channels are membrane proteins that allow ions to diffuse across cellular membranes in a regulated manner.

CNG channels are ion channels regulated by the direct binding of cyclic nucleotides.

Photoreceptors are retinal cells that contain a high density of ion channels regulated by the binding of cyclic nucleotides.

Olfaction is the process of odour sensation, also regulated by the binding of cyclic nucleotides.

Permeation describes the ability of ion channels to selectively determine which ions can move through them.

Gating is the process by which ion channels open and close to control the flow of ions.

Structure/function describes the relationship between the 3D structure of an ion channel and its function.

Cyclic nucleotides are small ligands used to control the gating of CNG channels.
Extremophiles and Biotechnology
Authors: Antranikian G
Published: March 2009

Microbial diversity in extreme habitats, e.g. the deep subsurface, polar regions, salt lakes, hot springs, solfataric field and alklaine lakes, is very broad and delivers a valuable resource of unique enzymes (extremozymes) and chemical compounds. The study of these extremophiles will provide new keys to the understanding of life processes under stress conditions and will unravel the mechanisms developed by biological systems to cope to harsh conditions. This gained knowledge will be used to develop new biobased products and bioprocesses in various fields such as fine chemicals, feed, food, cosmetics, textile, paper and pharmaceutical industries.
Geminiviridae
Authors: Briddon Rob W , Stanley John
Published: March 2009

The
Geminiviridae
comprise a group of plant viruses with small, circular, single‐stranded
deoxyribonucleic acid
(DNA) genomes encapsidated in particles that have a twinned quasi‐icosahedral (geminate) shape, from which the family derives its name. They are among the smallest of viruses known and are transmitted exclusively by specific insect vectors. Some are associated with highly diverse circular, single‐stranded DNA betasatellites that are essential for disease progression. Their association with alphasatellites provides evidence of the interaction of geminiviruses with other families of plant‐infecting viruses. Collectively, geminiviruses are pathogens of cereals, vegetable and fibre crops, posing a serious threat to agriculture worldwide. Efforts to control these viruses by conventional means, such as using insecticides against their insect vectors and by breeding resistance, have either proven unsuccessful or have not been durable. For this reason, researchers are increasingly looking to engineered resistance as a means to control these important diseases.

Key Concepts:

Geminiviruses are important insect‐transmitted pathogens of cereal, vegetable and fibre crops in tropical and temperate regions throughout the World, including developed and developing countries.

Geminiviruses often cause striking symptoms in plants, indeed the earliest description of virus symptoms in plants is believed to relate to those caused by a geminivirus, and such symptoms occasionally are considered to be horticulturally desirable.

All geminiviruses have single‐stranded DNA genomes and a twinned particle morphology that is unique to this family of plant viruses.

Some geminiviruses are associated with single‐stranded DNA satellites, referred to as alphasatellites and betasatellites, the latter playing an essential role in maintenance of the disease.

Because their small DNA genomes encode only a limited number of genes, geminiviruses manipulate the metabolism of the infected cell to produce conditions suitable for their proliferation.

Geminiviruses are proving invaluable in the investigation of fundamental biological processes such as DNA replication, cell cycle regulation, gene expression and pathogen resistance in plants.

Geminiviruses are highly recombinogenic, and the derivation of a large number of geminivirus and satellite DNA sequences is providing important insights into their diversity, adaptability and evolution.

Conventional control strategies, such as the use of chemicals to eliminate their insect vectors and breeding natural host plant resistance, have proven ineffective in reducing crop losses to geminivirus infection, leading to the development of promising alternative (genetically engineered) strategies.

Sequences derived from geminiviruses are being used to develop systems for high‐level expression of valuable proteins in plants.
Haematopoietic Growth Factors
Authors: Thomas Daniel , Lopez Angel F
Published: March 2009

Haematopoietic growth factors regulate the production of all the cellular elements of blood by stimulating the proliferation, survival and differentiation of haematopoietic cells in various stages of maturation and also enhancing certain mature cell functions. Recombinant growth factors are used in the clinic to stimulate cell production as part of treatment for anaemia, neutropenia and thrombocytopenia and to aid in the collection of bone marrow stem cells.
Melanoma
Authors: Villanueva Jessie , Herlyn Meenhard
Published: March 2009

Melanoma is a form of skin cancer that originates from specialized cells in the skin called melanocytes. Environmental, biochemical, molecular and genetic factors are all involved in the genesis of melanoma. Although the incidence of melanoma continues to rise worldwide, no current effective treatment is available for metastatic disease. Thus, development of new and efficacious strategies to treat this aggressive disease is urgently needed. Understanding the molecular and cellular basis of melanoma initiation, progression and metastasis is critical to identify new targets for novel therapeutic approaches that would improve survival and offer hope to patients coping with this aggressive neoplasm.

Key Concepts:

Melanoma is a serious form of skin cancer that originates from pigment‐producing cells called melanocytes.

The incidence of melanoma continues to rise worldwide, constituting a serious public health problem.

Major risk factors for melanoma include exposure to UV radiation, fair skin, large number of dysplastic nevi and a family history of melanoma.

Multiple factors, including genetic, molecular and environmental contribute to the development of melanoma.

Mutations in genes critical for proliferation (e.g. BRAF) and survival (e.g. AKT) contribute to melanomagenesis.

Metastatic melanoma is highly resistant to current therapies.

Targeting signalling pathways that are essential for tumour progression and maintenance, such as BRAF/MAPK and PI3K/AKT, offer a rational approach for the development of effective antimelanoma therapies