bluuebunny/crossref_metadata_2025 huggingface dataset:
Potential Application of ASTM C1701 for Evaluating Surface Infiltration of Permeable Interlocking Concrete Pavements
Authors: Smith David R. , Earley Kevin , Lia Justin M.
Published: January 2013

As a sister sustainable pavement to pervious concrete, permeable interlocking concrete pavement (PICP) has seen increased use for stormwater management and low impact development. Surface infiltration is a key performance indicator for both pavement types. This paper provides a brief background of the development of test methods for measuring the surface infiltration of permeable pavements. Among these test methods is the single ring infiltrometer method described in ASTM C1701, which was developed to test the surface infiltration of PICP, concrete grid pavements, and pervious concrete. Research literature references on surface infiltration testing at sites in Long Island, NY, confirm that ASTM C1701 is suitable for measuring the surface infiltration rate of PICP. The post-construction pavement surface infiltration results there demonstrated an average rate of 1.4 × 10−3 m/s (200 in./h) or greater. Test results are also referenced from U.S. Environmental Protection Agency surface infiltration testing that used a modified version of ASTM C1701 at a permeable pavement research facility in Edison, NJ, consisting of PICP, pervious concrete, and porous asphalt. Modifications to ASTM C1701 are proposed that include the use of (1) modeling clay to seal the ring to the pavement in hot weather and (2) graduated bucket(s) to determine the mass of infiltrated water. Graduations can eliminate the use of a scale on the test site to determine the infiltrated water's mass. In addition, changes to ASTM C1701 are proposed to include PICP, concrete grid pavements, and porous asphalt for comparative purposes.
Impact of Pervious Concrete Porosity on Permeability by 3D Image Analysis
Authors: Meulenyzer Samuel , Stora Eric , Perez Fabien
Published: January 2013

Pervious concrete is an effective solution to manage storm water runoff because of its ability to allow permeation of huge quantities of water. The objective of the present study is to define relationships between formulation parameters (like aggregate sizes and paste quantities) and final properties of pervious concrete (permeability, mechanical resistance, and porosity) through 3D images obtained by micro-tomography. Through an original experimental program, we attempt to determine the permeability of different pervious concretes directly from microstructural parameters extracted from 3D images. We exploit mathematical morphology tools, such as two-point correlation functions to access specific surface area, porosity value, and granulometric distribution of porosity. The permeability of pervious concrete is finally estimated by solving the Stokes equation on the 3D pore network numerically with finite elements. Permeability values obtained from 2D images and 3D acquisitions with water permeability measured in laboratory are then compared.
Risk Evaluation Approach for Polymers in Oxygen Breathing Systems
Authors: Chiffoleau Gwenael J. , Newton Barry E. , Forsyth Bradley S. , Forsyth Elliot T.
Published: January 2013

An approach for fire risk assessment of polymers in oxygen breathing systems is presented. The approach separates the fire risk of polymers into the probability of ignition and the consequence (severity) of ignition. Recommended methods for estimating the probability of ignition, the severity of fire damage, and the severity of any toxic combustion product exposure are provided. The ignition probability and severity of fire damage are based on ASTM G63. The severity of toxic combustion product exposure is based on ISO 15001 and a new methodology developed as part of a toxicity risk research program. Consistent with international risk assessment standards for medical devices (ISO 14971), the approach then combines the elements of risk according to the risk evaluation method. To complete the risk assessment, mitigation strategies are also presented for various results of the risk evaluation.
ASTM Committee C07 on Lime: A Reflection
Authors: Tate Michael J.
Published: January 2013

For the last 100 years ASTM Committee C07 (Lime) has provided guidance to the lime industry and its customers related to the methods of testing and specifications for limestone and lime products and their applications. A broad range of lime user, producer, and general interest input was provided and refined through a consensus process to create and maintain these standards. The first of the C-series of standards was C1-1902 Standard for Cement, Lime and Clay Products. As each industry matured, separate committees were developed with the C7 Committee on Lime formed in 1912. ASTM C5-1913 (Quicklime for Structural Purposes) is one of the oldest standards in the C-series of standards still active. An active area for work in the beginning years of the committee was the improvement of lime products for mortar, plaster, and stucco applications. This was the largest market for lime products in 1912, but the lime putty used for construction had several drawbacks when compared to substitute products and systems. Significant research into understanding and addressing these drawbacks was needed. This work resulted in the development of new standards for Finish Lime (C206) and Masons Lime (C207) that defined a Type-S hydrated lime, which had excellent workability and soundness properties. The number of applications for lime products has grown significantly over the last 100 years. Although, initially, construction was the largest lime market, the use of these products in metallurgical, environmental, and chemical/industrial applications is far larger today. As new applications have developed, C07 has responded with methods of tests to characterize products and standards for performance. There is value in the standards development process for both users and producers. Users obtain information related to lime products and producers obtain information related to the application. Standard test methods can be developed to predict product performance. Key parameters can be placed in a standard to provide manufacturing targets and insure product performance. In the future continued research and development of the applications for lime is needed. Insuring that the committee is balanced will maintain the quality of the committee work. Continued work toward harmonization with standards outside of ASTM is needed. Finally, C07 must look beyond traditional products to include by-product materials, like lime kiln dust (LKD), in standards where they are applicable.
Transsynaptic Tracing with Vesicular Stomatitis Virus Reveals Novel Retinal Circuitry
Authors: Beier Kevin T. , Borghuis Bart G. , El-Danaf Rana N. , Huberman Andrew D. , Demb Jonathan B. , Cepko Constance L.
Published: January 2013

The use of neurotropic viruses as transsynaptic tracers was first described in the 1960s, but only recently have such viruses gained popularity as a method for labeling neural circuits. The development of retrograde monosynaptic tracing vectors has enabled visualization of the presynaptic sources onto defined sets of postsynaptic neurons. Here, we describe the first application of a novel viral tracer, based on vesicular stomatitis virus (VSV), which directs retrograde transsynaptic viral spread between defined cell types. We use this virus in the mouse retina to show connectivity between starburst amacrine cells (SACs) and their known synaptic partners, direction-selective retinal ganglion cells, as well as to discover previously unknown connectivity between SACs and other retinal ganglion cell types. These novel connections were confirmed using physiological recordings. VSV transsynaptic tracing enables cell type-specific dissection of neural circuitry and can reveal synaptic relationships among neurons that are otherwise obscured due to the complexity and density of neuropil.
RaxIs a Selector Gene for Mediobasal Hypothalamic Cell Types
Authors: Lu Fuqu , Kar Deepon , Gruenig Nicole , Zhang Zi Wei , Cousins Nicole , Rodgers Helen M. , Swindell Eric C. , Jamrich Milan , Schuurmans Carol , Mathers Peter H. , Kurrasch Deborah M.
Published: January 2013

The brain plays a central role in controlling energy, glucose, and lipid homeostasis, with specialized neurons within nuclei of the mediobasal hypothalamus, namely the arcuate (ARC) and ventromedial (VMH), tasked with proper signal integration. Exactly how the exquisite cytoarchitecture and underlying circuitry becomes established within these nuclei remains largely unknown, in part because hypothalamic developmental programs are just beginning to be elucidated. Here, we demonstrate that theRetina and anterior neural fold homeobox(Rax) gene plays a key role in establishing ARC and VMH nuclei in mice. First, we show thatRaxis expressed in ARC and VMH progenitors throughout development, consistent with genetic fate mapping studies demonstrating thatRax+ lineages give rise to VMH neurons. Second, the conditional ablation ofRaxin a subset of VMH progenitors using aShh::Credriver leads to a fate switch from a VMH neuronal phenotype to a hypothalamic but non-VMH identity, suggesting thatRaxis a selector gene for VMH cellular fates. Finally, the broader elimination ofRaxthroughout ARC/VMH progenitors usingSix3::Creleads to a severe loss of both VMH and ARC cellular phenotypes, demonstrating a role forRaxin both VMH and ARC fate specification. Combined, our study illustrates thatRaxis required in ARC/VMH progenitors to specify neuronal phenotypes within this hypothalamic brain region.Raxthus provides a molecular entry point for further study of the ontology and establishment of hypothalamic feeding circuits.
Optogenetic Inhibition of Dorsal Medial Prefrontal Cortex Attenuates Stress-Induced Reinstatement of Palatable Food Seeking in Female Rats
Authors: Calu Donna J. , Kawa Alex B. , Marchant Nathan J. , Navarre Brittany M. , Henderson Mark J. , Chen Billy , Yau Hau-Jie , Bossert Jennifer M. , Schoenbaum Geoffrey , Deisseroth Karl , Harvey Brandon K. , Hope Bruce T. , Shaham Yavin
Published: January 2013

Relapse to maladaptive eating habits during dieting is often provoked by stress. Recently, we identified a role of dorsal medial prefrontal cortex (mPFC) neurons in stress-induced reinstatement of palatable food seeking in male rats. It is unknown whether endogenous neural activity in dorsal mPFC drives stress-induced reinstatement in female rats. Here, we used an optogenetic approach, in which female rats received bilateral dorsal mPFC microinjections of viral constructs coding light-sensitive eNpHR3.0–eYFP or control eYFP protein and intracranial fiber optic implants. Rats were food restricted and trained to lever press for palatable food pellets. Subsequently, pellets were removed, and lever pressing was extinguished; then the effect of bilateral dorsal mPFC light delivery on reinstatement of food seeking was assessed after injections of the pharmacological stressor yohimbine (an α-2 andrenoceptor antagonist) or pellet priming, a manipulation known to provoke food seeking in hungry rats. Dorsal mPFC light delivery attenuated yohimbine-induced reinstatement of food seeking in eNpHR3.0-injected but not eYFP-injected rats. This optical manipulation had no effect on pellet-priming-induced reinstatement or ongoing food-reinforced responding. Dorsal mPFC light delivery attenuated yohimbine-induced Fos immunoreactivity and disrupted neural activity duringin vivoelectrophysiological recording in awake rats. Optical stimulation caused significant outward currents and blocked electrically evoked action potentials in eNpHR3.0-injected but not eYFP-injected mPFC hemispheres. Light delivery alone caused no significant inflammatory response in mPFC. These findings indicate that intracranial light delivery in eNpHR3.0 rats disrupts endogenous dorsal mPFC neural activity that plays a role in stress-induced relapse to food seeking in female rats.
Synchronous and Asynchronous Theta and Gamma Activity during Episodic Memory Formation
Authors: Burke John F. , Zaghloul Kareem A. , Jacobs Joshua , Williams Ryan B. , Sperling Michael R. , Sharan Ashwini D. , Kahana Michael J.
Published: January 2013

To test the hypothesis that neural oscillations synchronize to mediate memory encoding, we analyzed electrocorticographic recordings taken as 68 human neurosurgical patients studied and subsequently recalled lists of common words. To the extent that changes in spectral power reflect synchronous oscillations, we would expect those power changes to be accompanied by increases in phase synchrony between the region of interest and neighboring brain areas. Contrary to the hypothesized role of synchronous gamma oscillations in memory formation, we found that many key regions that showed power increases during successful memory encoding also exhibited decreases in global synchrony. Similarly, cortical theta activity that decreases during memory encoding exhibits both increased and decreased global synchrony depending on region and stage of encoding. We suggest that network synchrony analyses, as used here, can help to distinguish between two major types of spectral modulations: (1) those that reflect synchronous engagement of regional neurons with neighboring brain areas, and (2) those that reflect either asynchronous modulations of neural activity or local synchrony accompanied by global disengagement from neighboring regions. We show that these two kinds of spectral modulations have distinct spatiotemporal profiles during memory encoding.
Mechanosensitive TRPC1 Channels Promote Calpain Proteolysis of Talin to Regulate Spinal Axon Outgrowth
Authors: Kerstein Patrick C. , Jacques-Fricke Bridget T. , Rengifo Juliana , Mogen Brian J. , Williams Justin C. , Gottlieb Philip A. , Sachs Fredrick , Gomez Timothy M.
Published: January 2013

Intracellular Ca2+signals control the development and regeneration of spinal axons downstream of chemical guidance cues, but little is known about the roles of mechanical cues in axon guidance. Here we show that transient receptor potential canonical 1 (TRPC1) subunits assemble mechanosensitive (MS) channels onXenopusneuronal growth cones that regulate the extension and direction of axon outgrowth on rigid, but not compliant, substrata. Reducing expression of TRPC1 by antisense morpholinos inhibits the effects of MS channel blockers on axon outgrowth and local Ca2+transients. Ca2+influx through MS TRPC1 activates the protease calpain, which cleaves the integrin adaptor protein talin to reduce Src-dependent axon outgrowth, likely through altered adhesion turnover. We found that talin accumulates at the tips of dynamic filopodia, which is lost upon cleavage of talin by active calpain. This pathway may also be important in axon guidance decisions since asymmetric inhibition of MS TRPC1 is sufficient to induce growth cone turning. Together our results suggest that Ca2+influx through MS TRPC1 on filopodia activates calpain to control growth cone turning during development.
The Angelman Syndrome Protein Ube3a Is Required for Polarized Dendrite Morphogenesis in Pyramidal Neurons
Authors: Miao Sheng , Chen Renchao , Ye Jiahao , Tan Guo-He , Li Shuai , Zhang Jing , Jiang Yong-hui , Xiong Zhi-Qi
Published: January 2013

Pyramidal neurons have a highly polarized dendritic morphology, characterized by one long apical dendrite and multiple short basal dendrites. They function as the primary excitatory cells of the mammalian prefrontal cortex and the corticospinal tract. However, the molecular mechanisms underlying the development of polarized dendrite morphology in pyramidal neurons remain poorly understood. Here, we report that the Angelman syndrome (AS) protein ubiquitin-protein ligase E3A (Ube3a) plays an important role in specifying the polarization of pyramidal neuron dendritic arbors in mice. shRNA-mediated downregulation of Ube3a selectively inhibited apical dendrite outgrowth and resulted in impaired dendrite polarity, which could be rescued by coexpressing mouse Ube3a isoform 2, but not isoform 1 or 3. Ube3a knockdown also disrupted the polarized distribution of the Golgi apparatus, a well established cellular mechanism for asymmetric dendritic growth in pyramidal neurons. Furthermore, downregulation of Ube3a completely blocked Reelin-induced rapid deployment of Golgi into dendrite. Consistently, we also observed selective inhibition of apical dendrite outgrowth in pyramidal neurons in a mouse model of AS. Overall, these results show that Ube3a is required for the specification of the apical dendrites and dendrite polarization in pyramidal neurons, and suggest a novel pathological mechanism for AS.
Different Orientation Tuning of Near- and Far-Surround Suppression in Macaque Primary Visual Cortex Mirrors Their Tuning in Human Perception
Authors: Shushruth S. , Nurminen Lauri , Bijanzadeh Maryam , Ichida Jennifer M. , Vanni Simo , Angelucci Alessandra
Published: January 2013

In primary visual cortex (V1), neuronal responses to stimuli inside the receptive field (RF) are usually suppressed by stimuli in the RF surround. This suppression is orientation specific. Similarly, in human vision surround stimuli can suppress perceived contrast of a central stimulus in an orientation-dependent manner. The surround consists of two regions likely generated by different circuits: a near-surround generated predominantly by geniculocortical and intra-V1 horizontal connections, and a far-surround generated exclusively by interareal feedback. Using stimuli confined to the near- or far-surround of V1 neurons, and similar stimuli in human psychophysics, we find that near-surround suppression is more sharply orientation tuned than far-surround suppression in both macaque V1 and human perception. These results point to a similarity between surround suppression in macaque V1 and human vision, and suggest that feedback circuits are less orientation biased than horizontal circuits. We find the sharpest tuning of near-surround suppression in V1 layers (3, 4B, 4Cα) with patterned and orientation-specific horizontal connections. Sharpest tuning of far-surround suppression occurs in layer 4B, suggesting greater orientation specificity of feedback to this layer. Different orientation tuning of near- and far-surround suppression may reflect a statistical bias in natural images, whereby nearby edges have higher probability than distant edges of being co-oriented and belonging to the same contour. Surround suppression would, thus, increase the coding efficiency of frequently co-occurring contours and the saliency of less frequent ones. Such saliency increase can help detect small orientation differences in nearby edges (for contour completion), but large orientation differences in distant edges (for directing saccades/attention).
Why Mental Arithmetic Counts: Brain Activation during Single Digit Arithmetic Predicts High School Math Scores
Authors: Price Gavin R. , Mazzocco Michèle M. M. , Ansari Daniel
Published: January 2013

Do individual differences in the brain mechanisms for arithmetic underlie variability in high school mathematical competence? Using functional magnetic resonance imaging, we correlated brain responses to single digit calculation with standard scores on the Preliminary Scholastic Aptitude Test (PSAT) math subtest in high school seniors. PSAT math scores, while controlling for PSAT Critical Reading scores, correlated positively with calculation activation in the left supramarginal gyrus and bilateral anterior cingulate cortex, brain regions known to be engaged during arithmetic fact retrieval. At the same time, greater activation in the right intraparietal sulcus during calculation, a region established to be involved in numerical quantity processing, was related to lower PSAT math scores. These data reveal that the relative engagement of brain mechanisms associated with procedural versus memory-based calculation of single-digit arithmetic problems is related to high school level mathematical competence, highlighting the fundamental role that mental arithmetic fluency plays in the acquisition of higher-level mathematical competence.
The Human Bitter Taste Receptor TAS2R10 Is Tailored to Accommodate Numerous Diverse Ligands
Authors: Born Stephan , Levit Anat , Niv Masha Y. , Meyerhof Wolfgang , Behrens Maik
Published: January 2013

Bitter taste is a basic taste modality, required to safeguard animals against consuming toxic substances. Bitter compounds are recognized by G-protein-coupled bitter taste receptors (TAS2Rs). The human TAS2R10 responds to the toxic strychnine and numerous other compounds. The mechanism underlying the development of the broad tuning of some TAS2Rs is not understood. Using comparative modeling, site-directed mutagenesis, and functional assays, we identified residues involved in agonist-induced activation of TAS2R10, and investigated the effects of different substitutions on the receptor's response profile. Most interestingly, mutations in S853.29and Q1755.40have differential impact on stimulation with different agonists. The fact that single point mutations lead to improved responses for some agonists and to decreased activation by others indicates that the binding site has evolved to optimally accommodate multiple agonists at the expense of reduced potency. TAS2R10 shares the agonist strychnine with TAS2R46, another broadly tuned receptor. Engineering the key determinants for TAS2R46 activation by strychnine in TAS2R10 caused a loss of response to strychnine, indicating that these paralog receptors display different strychnine-binding modes, which suggests independent acquisition of agonist specificities. This implies that the gene duplication event preceding primate speciation was accompanied by independent evolution of the strychnine-binding sites.
Alert Response to Motion Onset in the Retina
Authors: Chen Eric Y. , Marre Olivier , Fisher Clark , Schwartz Greg , Levy Joshua , da Silveira Rava Azeredo , Berry Michael J.
Published: January 2013

Previous studies have shown that motion onset is very effective at capturing attention and is more salient than smooth motion. Here, we find that this salience ranking is present already in the firing rate of retinal ganglion cells. By stimulating the retina with a bar that appears, stays still, and then starts moving, we demonstrate that a subset of salamander retinal ganglion cells, fast OFF cells, responds significantly more strongly to motion onset than to smooth motion. We refer to this phenomenon as an alert response to motion onset. We develop a computational model that predicts the time-varying firing rate of ganglion cells responding to the appearance, onset, and smooth motion of a bar. This model, termed the adaptive cascade model, consists of a ganglion cell that receives input from a layer of bipolar cells, represented by individual rectified subunits. Additionally, both the bipolar and ganglion cells have separate contrast gain control mechanisms. This model captured the responses to our different motion stimuli over a wide range of contrasts, speeds, and locations. The alert response to motion onset, together with its computational model, introduces a new mechanism of sophisticated motion processing that occurs early in the visual system.
Testing the Sorption Hypothesis in Olfaction: A Limited Role for Sniff Strength in Shaping Primary Odor Representations During Behavior
Authors: Cenier Tristan , McGann John P. , Tsuno Yusuke , Verhagen Justus V. , Wachowiak Matt
Published: January 2013

The acquisition of sensory information during behavior shapes the neural representation, central processing, and perception of external stimuli. In mammals, a sniff represents the basic unit of odor sampling, yet how sniffing shapes odor representations remains poorly understood. Perhaps the earliest hypothesis of the role of sniffing in olfaction arises from the fact that odorants with different physicochemical properties exhibit different patterns of deposition across the olfactory epithelium, and that these patterns are differentially affected by flow rate. However, whether sniff flow rates shape odor representations during natural sniffing remains untested, and whether animals make use of odorant sorption–airflow relationships as part of an active odor-sampling strategy remains unclear. We tested these ideas in the intact rat using a threefold approach. First, we asked whether sniff strength shapes odor representationsin vivoby imaging from olfactory receptor neuron (ORN) terminals during controlled changes in inhalation flow in the anesthetized rat. Second, we asked whether sniff strength shapes odor representations by imaging from ORNs during natural sniffing in the awake rat. Third, we asked whether rats actively modulate sniff strength during an odor discrimination task. We found that, while artificial changes in flow rate can alter ORN responses, sniff strength has negligible effect on odor representations during natural sniffing, and behaving rats do not modulate flow rate to improve odor discrimination. These data suggest that modulating sniff strength does not shape odor representations sufficiently to be part of a strategy for active odor sensing in the behaving animal.
Family Media Matters: Unraveling the Intergenerational Transmission of Reading and Television Tastes
Authors: Notten Natascha , Kraaykamp Gerbert , Konig Ruben P.
Published: January 2013

In this study, the authors scrutinize the intergenerational transmission of book reading and television viewing behaviors. They examine long-term effects of parents' social status, parental media example, and media guidance activities during one's childhood on adult media tastes. Data are employed from the Family Survey of the Dutch Population. By estimating structural equation models, the authors gained more insight into how parental socialization efforts influence children's book reading and television viewing. Unraveling direct and indirect effects, they found that both parental socioeconomic status and media socialization activities play a major role in the intergenerational transmission of media tastes. Imitation appeared to be the main mechanism underlying the media socialization process. Parental media guidance, both directly and via its effect on children's school success, partly mediates the imitation process, especially for reading. The current study above all shows that parental media socialization activities do enduringly affect a person's media taste. Hence, socialization is found to play an indispensable role in the development of both highbrow and lowbrow reading and television tastes.
‘Planning’ talk and traumatic brain injury
Authors: Barnes Scott Edward
Published: January 2013

Task-based activities of daily living are often a target of assessment and intervention for people with acquired communication disorders, but their interactional organization has not undergone detailed investigation. This study explores a task-based interaction focused on ‘planning’ involving a man with TBI and his friend. It analyses a half hour recording in which they planned errands that would need to be completed before the man with TBI departed for an overseas holiday. Conversation analytic single episode analysis is used. Discussion focuses on the phases and actions that were used during planning talk. Some speculation about the utility of these practices for planning with a person with TBI is also put forward. Finally, it is suggested that, pending further investigation, a clinical focus on the actions described in the present study might prove useful for structuring and facilitating the participation of people with TBI in routine task-based activities.
The organization of repair in SSLD classroom discourse: how to expose the trouble-source
Authors: Radford Julie , Ireson Judy , Mahon Merle
Published: January 2013

As children with specific speech and language difficulties (SSLD) have problems processing language, they are vulnerable in the classroom since it is primarily an oral environment. Repairs offer a potentially useful source of information for the language learner but, to benefit from feedback about their errors or misunderstandings, children must notice the corrective potential in the stream of educational discourse. Repair practices (245) with children with SSLD were analysed quantitatively in terms of age and type of activity. They were also analysed sequentially, using conversation analysis. Repairs dealing with form (grammatical and phonological) were not immediately taken up by the children whereas those concerning meaning (lexical and content) mostly led to self-correction. One explanation is that, during form repair, the adults’ corrective moves are embedded in turns that perform multiple work, so that children attend primarily to meaning. Designs that may be better suited to exposing corrections are discussed, with particular reference to features of prosody.
Physio-chemico-thermo-mechanical properties of selected biodegradable polymers
Authors: Priyodip P. , Balaji S. , Kini M. Vijaya
Published: January 2013

Polymers from renewable resources recently attracted research community mainly because of environmental concerns, low cost, availability and their biodegradability after usage. However, the intrinsic deficiencies of natural biopolymers, including poor mechanical properties, poor water resistance and difficult processability limit their use. The analysis presented here, is on renewable, bio-based resins for their mechanical, morphological, thermal and hydrolytic properties. The resins were prepared from starch, cellulose, lignin, chitosan, gelatin and their derivatives. All these matrices had good thermoplastic and mechanical properties. Among these blends, a representative starch-based specimen had maximum load bearing capacity 118·17 N on tensile stress of 1·97 MPa and modulus 221·36 MPa. In case of lignin, maximum load bearing capacity was 19·96 N on tensile stress of 0·44 MPa and modulus 287·11 MPa. In chitosan, maximum load bearing capacity was 74·03 N on tensile stress of 1·68 MPa and modulus 372·35 MPa. In case of gelatin, maximum load bearing capacity was 46·43 N on tensile stress of 1·22 MPa and modulus 829·75 MPa. Mechanical strength based on modulus showed: gelatin > chitosan > lignin > starch > cellulose. Thermal withstanding trend (dry heat) showed: gelatin > lignin > chitosan > cellulose > starch, whereas moist heat showed: gelatin > lignin > starch > chitosan > cellulose. Microscopic observations and biodegradability is also discussed.
Surgical management of craniopharyngioma with third ventricle involvement
Authors: de Lara Danielle , Ditzel Filho Leo F. S. , Muto Jun , Otto Bradley A. , Carrau Ricardo L. , Prevedello Daniel M. , M.D.
Published: January 2013

Craniopharyngiomas are notorious for their ability to invade the hypothalamus and third ventricle. Although several transcranial approaches have been proposed for their treatment, the endonasal route provides direct access to the tumor with no need for cerebral retraction or manipulation of the optic apparatus. After the lesion is debulked, the unique angle of approach achieved with this technique enables the surgeon to perform an extra-capsular dissection and visualize the walls of the third ventricle, the foramina of Monro, and the anterior comissure. Moreover, the enhanced magnification and lighting afforded by the endoscope facilitate safe tumor removal, particularly in areas where there is loss of clear lesion delimitation and greater infiltration of the surrounding structures.

Herein we present the case of a 68-year-old female patient with a 3-month history of visual deterioration accompanied by worsening headaches. Investigation with magnetic resonance imaging revealed a heterogeneous mass in the suprasellar region, extending into the third ventricle and displacing the pituitary gland and stalk inferiorly. Hormonal profile was within expected range for her age. An endonasal, fully endoscopic, transplanum transtuberculum approach was performed. Gross-total removal was achieved and pathology confirmed the diagnosis of craniopharyngioma. Postoperative recovery was marked by transient diabetes insipidus. Closure was achieved with a pedicled nasoseptal flap; despite exploration of the third ventricle, there was no cerebrospinal fluid leakage. Pituitary function was preserved. Visual function has fully recovered and the patient has been uneventfully followed since surgery.

The video can be found here: http://youtu.be/it5mpofZl0Q.
Transcortical–transforaminal microscopic approach for purely intraventricular craniopharyngioma
Authors: Chamoun Roukoz , Couldwell William T.
Published: January 2013

Purely intraventricular craniopharyngiomas are rare and pose particular surgical challenges. The two main surgical approaches to these lesions based in the anterior third ventricle are the frontal transventricular approach (through a transcortical or transcallosal approach) and the trans–lamina terminalis approach. The authors note that the pituitary stalk in many of these cases is located in a normal position, which suggests that the third ventricular floor is intact. In such cases, the senior author chooses an approach to avoid disruption of the floor of the third ventricle. Specifically, a traditional frontotemporal approach is not used; we have found that in such cases, a frontal transventricular approach through the usually dilated foramen of Monro provides an optimal visualization of the tumor while minimizing the risks of injury to the hypothalamus and pituitary stalk. The endoscope can be very helpful in exploring blind angles, hidden from the microscopic view. Recognition of this rare location variant of craniopharyngioma is helpful in preoperative planning in an effort to reduce hypothalamic pituitary axis damage. Two patients presenting with craniopharyngiomas that were entirely intraventricular are shown in the video. The patients underwent removal of their tumors without incurring new long-term endocrine deficits.

The video can be found here: http://youtu.be/VFlhm_lsrGY.
Transcallosal approach for third ventriculostomy and removal of midbrain cavernous malformation
Authors: Couldwell William T.
Published: January 2013

Symptomatic brain stem cavernous malformations often present the dilemma of choosing an approach for their resection. Superior midline midbrain lesions are in a particularly challenging location, as they are less accessible via traditional lateral or posterior approaches. The author presents a case of a young woman who presented with a symptomatic cavernous malformation with surface presentation to the floor of the third ventricle. The lesion was causing sensory symptoms from local mass effect and hydrocephalus from occlusion of the Aqueduct of Sylvius. An approach was chosen to both perform a third ventriculostomy and remove the cavernous malformation. Through a right frontal craniotomy, a transcallosal–transforaminal approach was used to perform a third ventriculostomy. Through the same callosal opening, a subchoroidal approach was performed to provide access the cavernous malformation. The details of the procedure and nuances of technique are described in the narration.

The video can be found here: http://youtu.be/zKKnehp7l2c.
Registration of ‘Ho 02‐113’ Sugarcane
Authors: Hale Anna L. , Dufrene Edwis O. , Tew Thomas L. , Pan Yong-Bao , Viator Ryan P. , White Paul M. , Veremis John C. , White William H. , Cobill Robert , Richard Edward P. , Rukavina Hrvoje , Grisham Michael P.
Published: January 2013

‘Ho 02‐113’ (Reg. No. CV‐148, PI 665695) sugarcane (a complex hybrid of S. officinarum L., S. spontaneum L., S. barberi Jeswiet, and S. sinese Roxb. Amend. Jeswiet) was released by the USDA‐ARS Sugarcane Research Unit working cooperatively with the Louisiana State University Agricultural Center and the American Sugarcane League of the USA. This high‐fiber sugarcane cultivar was released for use as a biofuel feedstock to fill the rising industry demand. Ho 02‐113 is a progeny of the cross SES 234 × ‘LCP 85‐384’ made in Houma, LA in 2001. The cultivar was selected at the USDA‐ARS research farm in Schriever, LA, evaluated in multiple locations, and harvested from six southern Louisiana locations in six plant‐cane, two first‐ratoon, two second‐ratoon, and two third‐ratoon replicated tests. Ho 02‐113 averaged 125.3 Mg ha−1 total cane (TC) on a wet‐weight basis, 12.8 Mg ha−1 total soluble solids (TSS), 32.8 Mg ha−1 total fiber (TF), and 45.3 Mg ha−1 total fiber and soluble solids (TFSS). These values were significantly higher than those for the leading high‐fiber sugarcane cultivar L 79‐1002, which averaged 102.7 Mg ha−1 TC, 9.6 Mg ha−1 TSS, 27.8 Mg ha−1 TF, and 37.4 Mg ha−1 TFSS. The cultivar is resistant to leaf scald [caused by Xanthomonas albilinenas (Ashby) Dawson] and smut (caused by Ustilago scitaminea H. and P. Sydow) in inoculated tests and showed no symptoms either of brown rust (caused by Puccinia melanocephala H. and P. Sydow) or mosaic (caused by either Sugarcane mosaic virus or Sorghum mosaic virus) when exposed to high levels of natural inoculums.
Electrodialytic Transport Properties of Anion-Exchange Membranes Prepared from Poly(vinyl alcohol) and Poly(vinyl alcohol-co-methacryloyl aminopropyl trimethyl ammonium chloride)
Authors: Jikihara Atsushi , Ohashi Reina , Kakihana Yuriko , Higa Mitsuru , Kobayashi Kenichi
Published: January 2013

Random-type anion-exchange membranes (AEMs) have been prepared by blending poly(vinyl alcohol) (PVA) and the random copolymer-type polycation, poly(vinyl alcohol-co-methacryloyl aminopropyl trimethyl ammonium chloride) at various molar percentages of anion-exchange groups to vinyl alcohol groups, Cpc, and by cross-linking the PVA chains with glutaraldehyde (GA) solution at various GA concentrations, CGA. The characteristics of the random-type AEMs were compared with blend-type AEMs prepared in our previous study. At equal molar percentages of the anion exchange groups, the water content of the random-type AEMs was lower than that of the blend-type AEMs. The effective charge density of the random-type AEMs increased with increasing Cpc and reached a maximum value. Further, the maximum value of the effective charge density increased with increasing CGA. The maximum value of the effective charge density, 0.42 mol/dm3, was obtained for the random-type AEM with Cpc = 4.2 mol % and CGA = 0.15 vol %. A comparison of the random-type and blend-type AEMs with almost the same Cpc showed that the random-type AEMs had lower membrane resistance than the blend-type ones. The membrane resistance and dynamic transport number of the random-type AEM with Cpc = 6.0 mol % and CGA = 0.15 vol % were 4.8 Ω cm2 and 0.83, respectively.
Optimization of Shikonin Homogenate Extraction from Arnebia euchroma Using Response Surface Methodology
Authors: Liu Tingting , Ma Chunhui , Yang Lei , Wang Wenjie , Sui Xiaoyu , Zhao Chunjian , Zu Yuangang
Published: January 2013

An efficient homogenate extraction technique was employed for extracting shikonin from Arnebia euchroma. The homogenate extraction procedure was optimized and compared with other conventional extraction techniques. The proposed method gave the best result with the highest extraction efficiency in the shortest extraction time. Based on single-factor experiments, a three-factor-three-level experimental design has been developed by Box-Behnken design. The optimal conditions were 78% ethanol as solvent, homogenate extraction time of 4.2 min, 10.3 liquid to solid ratio and two extraction cycles. Moreover, the proposed method was validated by stability, repeatability and recovery experiments. The developed homogenate extraction method provided a good alternative for the extraction of shikonin from A. euchroma. The results indicated that the proposed homogenate extraction was a convenient, rapid and efficient sample preparation technique and was environmental friendly. Furthermore, homogenate extraction has superiority in the extraction of thermally sensitive compounds from plant matrices.
Antioxidant Properties of cis-Z,Z'-3a.7a',7a.3a'-Dihydroxy-ligustilide on Human Umbilical Vein Endothelial Cells in Vitro
Authors: Li Weidong , Wu Yu , Liu Xuedong , Yan Cuiping , Liu Dan , Pan Yang , Yang Guangming , Yin Fangzhou , Weng Zebin , Zhao Ding , Chen Zhipeng , Cai Baochang
Published: January 2013

A new chemical component, cis-Z,Z'-3a.7a',7a.3a'-dihydroxyligustilide, was isolated from Angelica sinensis and its structure elucidated from its NMR and MS spectra and confirmed by X-ray single crystal diffraction analysis. We also explored the antioxidative properties of cis-Z,Z'-3a.7a',7a.3a'-dihydroxyligustilide on human umbilical vein endothelial cells (HUVECs) against injuries induced by hydrogen peroxide (H2O2) using an MTT assay and flow cytometry analysis. In addition, the activities of superoxide dismutase (SOD), malondialdehyde (MDA), lactate dehydrogenase (LDH), nitric oxide (NO) and reactive oxygen species (ROS) were determined. We found that cis-Z,Z'-3a.7a',7a.3a'-dihydroxyligustilide increased the viability of HUVECs injured by H2O2 in a dose-dependent manner, reduced the apoptosis of HUVEC, and enhanced HUVEC proliferation. Our results demonstrated the remarkable in vitro antioxidative activities of this compound, indicating that it could be a potential antioxidant with protective effects against H2O2-induced HUVEC injuries.
Enaminonitriles in Heterocyclic Synthesis: A Route to 1,3-Diaryl-4-aminopyrazole Derivatives
Authors: Medrasi Hanadi , Al-Sheikh Mariam , Salaheldin Abdellatif
Published: January 2013

Benzylcyanide and 4-nitrobenzylcyanide condensed with triethyl orthoformate and piperidine or morpholine to yield 2-aryl-2-piperidinyl or 2-morpholinylacrylonitriles. These coupled with aromatic diazonium salts to yield the 2-arylhydrazno-2-arylethane nitriles in good yields. The latter were converted into 4-aminopyrazoles in good yields using the Thorpe-Ziegler cyclization.
Lamb Waves Propagation along 3C-SiC/AlN Membranes for Application in Temperature-Compensated, High-Sensitivity Gravimetric Sensors
Authors: Caliendo Cinzia , D'Amico Arnaldo , Lo Castro Fabio
Published: January 2013

The propagation of the fundamental quasi-symmetric Lamb mode S0 travelling along 3C-SiC/c-AlN composite plates is theoretically studied with respect to the AlN and SiC film thickness, the acoustic wave propagation direction and the electrical boundary conditions. The temperature effects on the phase velocity have been considered for four AlN/SiC-based electroacoustic coupling configurations, specifically addressing the design of temperature-compensated, enhanced-coupling, GHz-range electroacoustic devices. The gravimetric sensitivity and resolution of the four temperature-stable SiC/AlN composite structures are theoretically investigated with respect to both the AlN and SiC sensing surface. The SiC/AlN-based sensor performances are compared to those of surface acoustic waves and Lamb S0 mode mass sensors implemented on bulk conventional piezoelectric materials and on thin suspended membranes.
Ochratoxin A Management in Vineyards by Lobesia botrana Biocontrol
Authors: Cozzi Giuseppe , Somma Stefania , Haidukowski Miriam , Logrieco Antonio
Published: January 2013

Grape berries attacked by Lobesia botrana larvae are more easily infected by Aspergillus section Nigri (black aspergilli) ochratoxigenic species. Two-year field trials were carried out in Apulia (Italy) to evaluate a bioinsecticide control strategy against L. botrana and the indirect effect on reducing ochratoxin A (OTA) contamination in vineyards. A commercial Bacillus thuringiensis formulate and an experimental Beauveria bassiana (ITEM-1559) formulate were tested in two vineyards cultivated with the same grape variety, Negroamaro, but with two different training systems (espalier and little-arbor techniques). In both years and training systems the treatments by B. bassiana ITEM-1559 significantly controlled L. botrana larvae attacks with effectiveness similar to B. thuringensis (more than 20%). A significant reduction of OTA concentrations (up to 80% compared to untreated controls) was observed only in the first year in both training systems, when the metereological parameters prior to harvest were more favorable to the insect attack. Results of field trials showed that B. bassiana ITEM-1559 is a valid bioinsecticide against L. botrana and that grape moth biocontrol is a strategy to reduce OTA contamination in vineyard in seasons with heavy natural infestation.
Diverting the downhill flow of auxin to steer growth during tropisms
Authors: Spalding Edgar P.
Published: January 2013

Polar auxin transport can be likened to water following the path of least resistance as it flows downhill. In the case of auxin, the hill is the difference in electrochemical potential of the auxin anion (IAA−). H+‐ATPases and H+‐IAA symporters at the plasma membrane create the electrical and IAA− concentration gradients that constitute this thermodynamic hill. PIN and ABCB transporters also at the plasma membrane bias the direction and limit the rate of downhill flow out of the cell. This article will present the thermodynamic basis for this view and critically examine how well the molecular biological descriptions of the polar auxin transport process fit the framework. An auxin concentration gradient across an organ has long been recognized as the cause of bending growth during tropisms. Its generation can be viewed as a result of redirected polar auxin transport. This article will examine how molecular regulation of the paths of least resistance to auxin efflux diverts the downhill flow of auxin to steer growth during tropisms.
GRAVITY PERSISTENT SIGNAL 1 (GPS1) Reveals Novel Cytochrome P450s Involved in Gravitropism
Authors: Withers John C. , Shipp Matthew J. , Rupasinghe Sanjeewa G. , Sukumar Poornima , Schuler Mary A. , Muday Gloria K. , Wyatt Sarah E.
Published: January 2013

• Premise: Gravity is an important environmental factor that affects growth and development of plants. In response to changes in gravity, directional growth occurs along the major axes and lateral branches of both shoots and roots. The gravity persistent signal (gps) mutants of Arabidopsis thaliana were previously identified as having an altered response to gravity when reoriented relative to the gravity vector in the cold, with the gps1 mutant exhibiting a complete loss of tropic response under these conditions.

• Methods: Thermal asymmetric interlaced (TAIL) PCR was used to identify the gene defective in gps1. Gene expression data, molecular modeling and computational substrate dockings, quantitative RT‐PCR analyses, reporter gene fusions, and physiological analyses of knockout mutants were used to characterize the genes identified.

• Results: Cloning of the gene defective in gps1 and genetic complementation revealed that GPS1 encodes CYP705A22, a cytochrome P450 monooxygenase (P450). CYP705A5, a closely related family member, was identified as expressed specifically in roots in response to gravistimulation, and a mutation affecting its expression resulted in a delayed gravity response, increased flavonol levels, and decreased basipetal auxin transport. Molecular modeling coupled with in silico substrate docking and diphenylboric acid 2‐aminoethyl ester (DBPA) staining indicated that these P450s are involved in biosynthesis of flavonoids potentially involved in auxin transport.

• Conclusion: The characterization of two novel P450s (CYP705A22 and CYP705A5) and their role in the gravity response has offered new insights into the regulation of the genetic and physiological controls of plant gravitropism.