Studies on the Effects of Bottom Trawling on the Benthic Fauna off Veraval Coast, Gujarat

Bottom trawling is one among the most destructive human induced physical disturbances inflicted to seabed and its living communities. The bottom trawls are designed to tow along the sea floor, which on its operation indiscriminately smashes everything on their way crushing, killing, burying and exposing to predators the benthic fauna. Bottom trawling causes physical and biological damages that are irreversible, extensive and long lasting. The commercial trawling fleet of India consists of 29,241 small and medium-fishing boats. The northwest coast of India has the largest fishing fleet consisting of 23,618 mechanized vessels, especially the bottom trawlers. However, attempts were not made to study the impact of bottom trawling along Northwest coast of India. The estimated optimum fleet size of Gujarat is 1,473 mechanised trawlers while 7402 commercial trawlers are operated from the coast of Gujarat. Veraval port was designed initially for 1,200 fishing trawlers but 2793 trawlers are being operated from this port making it the largest trawler port of Gujarat. The aim of this study was to investigate the effects of bottom trawling on the substratum and the associated benthic communities of commercial trawling grounds of Veraval coast. The study compared the differences between the samples collected before and after experimental trawling to detect the impacts of bottom trawling. Attempts were made to assess the possible impact of bottom trawling on:(i) the sediment characteristics (ii)the sediment heavy metals (iii) epifauna (iv) macrobenthos and (v) meiobenthos. This study is expected to generate information on trawling impacts of the studied area that will help in better management of the biological diversity and integrity of the benthic fauna off Veraval coast. An exhaustive review on the studies conducted around the world and in India on impact of bottom trawling on the benthic fauna is also detailed.In the present study, the bottom trawling induced variations on sediment organic matter, epifauna, macrobenthos and meiobenthos were evident. It was also observed that the seasonal/ natural variations were more prominent masking the trawling effect on sediment texture and heavy metals. Enforcement of control of excess bottom trawlers and popularization of semi pelagic trawls designed to operate a little distance above the sea bottom for off bottom resources will minimize disturbance on the sea bottom. Training and creating awareness in responsible fishing should be made mandatory requirements, to the coastal communities. They should be made wardens to protect the valuable resources for the benefit of sustainability. To protect the biodiversity and ecosystem health, the imminent need is to survey and make catalogue, identification of sensitive areas or hot spots and to adopt management strategies for the conservation and biodiversity protection of benthic fauna. The present study is a pioneering work carried out along Veraval coast. This thesis will provide a major fillip to the studies on impact of bottom trawling on the benthic fauna along the coast of India.

Magnetische Kopplungen in magneto-optischen Speicherschichten

Im Rahmen dieser Arbeit wurden magneto-optische Speicherschichten und ihre Kopplungen untereinander untersucht. Hierzu wurden zum Einen die für die magneto-optische Speichertechnologie "klassischen" Schichten aus RE/TM-Legierungen verwendet, zum Anderen aber auch erfolgreich Granate integriert, die bisher nicht in diesem Anwendungsgebiet verwendet wurden. Einleitend werden die magneto-optischen Verfahren, die resultierenden Anforderungen an die dünnen Schichten und die entsprechenden physikalischen Grundlagen diskutiert. Außerdem wird auf das Hochfrequenz-Sputtern von RE/TM-Legierungen eingegangen und die verwendeten magneto-optischen Messverfahren werden erläutert [Kap. 2 & 3]. Die Untersuchungen an RE/TM-Schichten bestätigen die aus der Literatur bekannten Eigenschaften. Sie lassen sich effektiv, und für magneto-optische Anwendungen geeignet, über RF-Sputtern herstellen. Die unmittelbaren Schicht-Parameter, wie Schichtdicke und Terbium-Konzentration, lassen sich über einfache Zusammenhänge einstellen. Da die Terbium-Konzentration eine Änderung der Kompensationstemperatur bewirkt, lässt sich diese mit Messungen am Kerr-Magnetometer überprüfen. Die für die Anwendung interessante senkrechte magnetische Anisotropie konnte ebenfalls mit den Herstellungsbedingungen verknüpft werden. Bei der Herstellung der Schichten auf einer glatten Glas-Oberfläche (Floatglas) zeigt die RE/TM-Schicht bereits in den ersten Lagen ein Wachstumsverhalten, das eine senkrechte Anisotropie bewirkt. Auf einer Quarzglas- oder Keramik-Oberfläche wachsen die ersten Lagen in einer durch das Substrat induzierten Struktur auf, danach ändert sich das Wachstumsverhalten stetig, bis eine senkrechte Anisotropie erreicht wird. Dieses Verhalten kann auch durch verschiedene Pufferschichten (Aluminium und Siliziumnitrid) nur unwesentlich beeinflusst werden [Kap. 5 & Kap. 6]. Bei der direkten Aufbringung von Doppelschichten, bestehend aus einer Auslese-Schicht (GdFeCo) auf einer Speicherschicht (TbFeCo), wurde die Austausch-Kopplung demonstriert. Die Ausleseschicht zeigt unterhalb der Kompensationstemperatur keine Kopplung an die Speicherschicht, während oberhalb der Kompensationstemperatur eine direkte Kopplung der Untergitter stattfindet. Daraus ergibt sich das für den MSR-Effekt erwünschte Maskierungsverhalten. Die vorher aus den Einzelschichten gewonnen Ergebnisse zu Kompensationstemperatur und Wachstumsverhalten konnten in den Doppelschichten wiedergefunden werden. Als Idealfall erweist sich hier die einfachste Struktur. Man bringt die Speicherschicht auf Floatglas auf und bedeckt diese direkt mit der Ausleseschicht [Kap. 7]. Weiterhin konnte gezeigt werden, dass es möglich ist, den Faraday-Effekt einer Granatschicht als verstärkendes Element zu nutzen. Im anwendungstauglichen, integrierten Schichtsystem konnten die kostengünstig, mit dem Sol-Gel-Verfahren produzierten, Granate die strukturellen Anforderungen nicht erfüllen, da sich während der Herstellung Risse und Löcher gebildet haben. Bei der experimentellen Realisierung mit einer einkristallinen Granatschicht und einer RE/TM-Schicht konnte die prinzipielle Eignung des Schichtsystems demonstriert werden [Kap. 8].

Lithography-free micro- and nanostructuring based on conventional plasma etching

In now-a-days semiconductor and MEMS technologies the photolithography is the working horse for fabrication of functional devices. The conventional way (so called Top-Down approach) of microstructuring starts with photolithography, followed by patterning the structures using etching, especially dry etching. The requirements for smaller and hence faster devices lead to decrease of the feature size to the range of several nanometers. However, the production of devices in this scale range needs photolithography equipment, which must overcome the diffraction limit. Therefore, new photolithography techniques have been recently developed, but they are rather expensive and restricted to plane surfaces. Recently a new route has been presented - so-called Bottom-Up approach - where from a single atom or a molecule it is possible to obtain functional devices. This creates new field - Nanotechnology - where one speaks about structures with dimensions 1 - 100 nm, and which has the possibility to replace the conventional photolithography concerning its integral part - the self-assembly. However, this technique requires additional and special equipment and therefore is not yet widely applicable. This work presents a general scheme for the fabrication of silicon and silicon dioxide structures with lateral dimensions of less than 100 nm that avoids high-resolution photolithography processes. For the self-aligned formation of extremely small openings in silicon dioxide layers at in depth sharpened surface structures, the angle dependent etching rate distribution of silicon dioxide against plasma etching with a fluorocarbon gas (CHF3) was exploited. Subsequent anisotropic plasma etching of the silicon substrate material through the perforated silicon dioxide masking layer results in high aspect ratio trenches of approximately the same lateral dimensions. The latter can be reduced and precisely adjusted between 0 and 200 nm by thermal oxidation of the silicon structures owing to the volume expansion of silicon during the oxidation. On the basis of this a technology for the fabrication of SNOM calibration standards is presented. Additionally so-formed trenches were used as a template for CVD deposition of diamond resulting in high aspect ratio diamond knife. A lithography-free method for production of periodic and nonperiodic surface structures using the angular dependence of the etching rate is also presented. It combines the self-assembly of masking particles with the conventional plasma etching techniques known from microelectromechanical system technology. The method is generally applicable to bulk as well as layered materials. In this work, layers of glass spheres of different diameters were assembled on the sample surface forming a mask against plasma etching. Silicon surface structures with periodicity of 500 nm and feature dimensions of 20 nm were produced in this way. Thermal oxidation of the so structured silicon substrate offers the capability to vary the fill factor of the periodic structure owing to the volume expansion during oxidation but also to define silicon dioxide surface structures by selective plasma etching. Similar structures can be simply obtained by structuring silicon dioxide layers on silicon. The method offers a simple route for bridging the Nano- and Microtechnology and moreover, an uncomplicated way for photonic crystal fabrication.

A View on Dyslexia

We describe here, briefly, a perceptual non-reading measure which reliably distinguishes between dyslexic persons and ordinary readers. More importantly, we describe a regimen of practice with which dyslexics learn a new perceptual strategy for reading. Two controlled experiment on dyslexics children demonstrate the regimen's efficiency.

Effect of joint mobilization on the H Reflex amplitude in people with spasticity

Objective: To determine the effect of ankle joint mobilization on the H reflex amplitude of thesoleus muscle in people with spasticity. Materials and methods: A quasi-experimental study withcrossover design and simple masking was conducted in 24 randomized subjects to initiate thecontrol or experimental group. Traction and rhythmic oscillation were applied for five minutesto the ankle joint. H wave amplitude changes of Hoffmann reflex (electrical equivalent of themonosynaptic spinal reflex) was assessed, stimulating the tibial nerve at the level of the poplitealfossa and recording in the soleus muscle. In each subject 12 measurements were taken: basalrate, during and after mobilization. Changes in H reflex amplitude were calculated in relationto basal measurement. For each measurement a hypothesis test was performed (Student t test).Results: In groups of patients with brain injury and incomplete spinal cord injury, a significantdifference was found between measurements of both studies, concerning variation in H reflexamplitude during the application of joint mobilization techniques, with a decrease in the experimentalgroup and an increase in the control group. In contrast, no significant differences werefound after mobilization therapy. Patients with complete spinal cord injury showed no significantdifferences in any measurements. Conclusion: We demonstrate the effectiveness of jointmobilization in the decrease of H reflex amplitude in patients with brain injury or incompletespinal cord injury during the mobilization maneuver, but no residual effect after completion ofthe trial. This research showed no evidence regarding excitability reduction in complete spinalcord injury. We suggest that therapeutic interventions to decrease muscle tone based on the jointmobilization should be reconsidered.

Corticoides versus Placebo o tratamiento conservador en Cefalea post punción dural. Revisión sistemática y metaanálisis

Introducción Se realizó una revisión sistemática de la literatura y metaanálisis para determinar la utilidad, en términos de reducción de la intensidad y la prevención de la cefalea post-punción dural, de los corticoides endovenosos. Materiales y métodos Revisión sistemática y metaanálisis, dos revisores seleccionaron y analizaron los artículos definidos en los términos de entrada, extrajeron características generales de los estudios incluidos, describieron los principales hallazgos y resumieron sus resultados. Se analizó la heterogeneidad por el coeficiente de I2 y Tau2 , la magnitud del efecto se analizó en el coeficiente Z, todos los estadísticos asumieron un nivel de significancia del 95%, en cuadros y figuras (de control de sesgos y Forres Plot) Resultados 75 Referencias fueron seleccionadas, 33 identificadas en la búsqueda y 48 por método de Snowball; Seis concordaron con los criterios de elegibilidad; 69 fueron excluidas por no cumplir con los criterios de inclusión; el enmascaramiento aspecto de mayor riesgo de sesgo (intermedio); en conjunto hubo buen control del riesgo de sesgo entre los estudios incluidos. Los resultados muestran baja heterogeneidad a favor de la intervención con corticoides en el tratamiento de la cefalea post-dural; amplia heterogeneidad y sin efecto para la prevención de la cefalea post-dural. Conclusiones Se recomienda el uso de hidrocortisona o metilprednisolona en la reducción de la intensidad de la cefalea post-dural. No se cuenta con evidencia de dexametasona en la prevención de cefalea postdural. Se requiere de estudios adicionales, con otras intervenciones farmacológicas que sobre la plausibilidad de la condición (cefalea post-dural) pudieran prevenir o disminuir su ocurrencia

The effect of doubled CO2 and model basic state biases on the monsoon-ENSO system. I: Mean response and interannual variability

The impact of doubled CO2 concentration on the Asian summer monsoon is studied using a coupled ocean-atmosphere model. Both the mean seasonal precipitation and interannual monsoon variability are found to increase in the future climate scenario presented. Systematic biases in current climate simulations of the coupled system prevent accurate representation of the monsoon-ENSO teleconnection, of prime importance for seasonal prediction and for determining monsoon interannual variability. By applying seasonally varying heat flux adjustments to the tropical Pacific and Indian Ocean surface in the future climate simulation, some assessment can be made of the impact of systematic model biases on future climate predictions. In simulations where the flux adjustments are implemented, the response to climate change is magnified, with the suggestion that systematic biases may be masking the true impact of increased greenhouse gas forcing. The teleconnection between ENSO and the Asian summer monsoon remains robust in the future climate, although the Indo-Pacific takes on more of a biennial character for long periods of the flux-adjusted simulation. Assessing the teleconnection across interdecadal timescales shows wide variations in its amplitude, despite the absence of external forcing. This suggests that recent changes in the observed record cannot be distinguished from internal variations and as such are not necessarily related to climate change.

The development and contribution of surface charge by crop residues in two Malawian acid soils

The effects of maize and soya bean residues on the pH and charge of a loamy sand (Kawalazi) and a sandy clay loam (Naming'omba) from Malawi were measured to determine both the indirect effect of the residues on soil charge through the changes in pH, and the direct contribution of charge carried on the residue surfaces. The soils had pH values (10 mM CaCl2) of 4.3 and 5.0 and organic matter contents were 1.4% and 2.7%, respectively. The clay fractions were dominated by kaolinite and goethite, and mica was present in both samples. The soils were incubated for 28 days with maize (Zea mays) and soya bean (Glycine max) residues. The maximum addition of residue (12.0%) in the Kawalazi and Naming'omba soils increased the pH from 4.3 and 5.0 to 4.8 and 5.3 (maize) and to 9.0 and 8.8 (soya bean), respectively. Negative charge increased from 2.1 and 4.7 cmol(c) kg(-1) to 3.8 and 7.5 (maize) and to 5.3 and 9.3 cmol(c) kg(-1) (soya bean). Positive charge increased from 0.72 and 0.62 to 0.87 and 0.85 cmol(c) kg(-1) (maize) and to 0.75 and 0.68 (soya bean). The charge contribution by the residues was calculated by difference between the charge on a sample incubated with residue and the charge on a soil without residue limed to the same pH value. Up to 100 cmolc negative charge and 10 cmol(c) of positive charge per kg of residue were directly contributed to the soil-residue mixture, the amounts depending on the type of residue, the extent to which the residue was decomposed in the soil and the pH of the mixture. The Anderson and Sposito method [Soil Sci. Soc. Am. J. 55 (1991) 1569] was used to partition the permanent negative charge (holding Cs+) from variable negative charge (holding Li+). In the pH range 3.7-6.5 the maize residue contributed between 3 and 26 cmol(c) of variable charge per kg of residue in the Kawalazi soil and between 6 and 25 cmol(c) per kg of residue in the Naming'omba soil. For soya bean the values were between I and 28 and between 4 and 68 cmolc per kg of residue, respectively. At a given pH value, the charge tended to increase with time of incubation and for a given addition of residue, pH decreased during incubation. Addition of residues contributed no permanent negative charge and the charge on the soil measured by Cs adsorption was independent of pH change caused by the residue showing that the method is valid for soil-residue mixtures. With time there was a decrease in the amount of permanent charge probably due to masking as humic material become adsorbed on mineral surfaces. (C) 2003 Elsevier Science B.V. All rights reserved.

Human amygdala responsivity to masked fearful eye whites

The amygdala was more responsive to fearful (larger) eye whites than to happy (smaller) eye whites presented in a masking paradigm that mitigated subjects' awareness of their presence and aberrant nature. These data demonstrate that the amygdala is responsive to elements of.

Scope and Limitations of The Co-Drug Approach to Topical Drug Delivery

Many currently available drugs show unfavourable physicochemical properties for delivery into or across the skin and temporary chemical modulation of the penetrant is one option to achieve improved delivery properties. Pro-drugs are chemical derivatives of an active drug which is covalently bonded to an inactive pro-moiety in order to overcome pharmaceutical and pharmacokinetic barriers. A pro-drug relies upon conversion within the body to release the parent active drug (and pro-moiety) to elicit its pharmacological effect. The main drawback of this approach is that the pro-moiety is essentially an unwanted ballast which, when released, can lead to adverse effects. The term ‘co-drug’ refers to two or more therapeutic compounds active against the same disease bonded via a covalent chemical linkage and it is this approach which is reviewed for the first time in the current article. For topically applied co-drugs, each moiety is liberated in situ, either chemically or enzymatically, once the stratum corneum barrier has been overcome by the co-drug. Advantages include synergistic modulation of the disease process, enhancement of drug delivery and pharmacokinetic properties and the potential to enhance stability by masking of labile functional groups. The amount of published work on co-drugs is limited but the available data suggest the co-drug concept could provide a significant therapeutic improvement in dermatological diseases. However, the applicability of the co-drug approach is subject to strict limitations pertaining mainly to the availability of compatible moieties and physicochemical properties of the overall molecule.

Viewing the body modulates tactile receptive fields

Tactile discrimination performance depends on the receptive field (RF) size of somatosensory cortical (SI) neurons. Psychophysical masking effects can reveal the RF of an idealized "virtual" somatosensory neuron. Previous studies show that top-down factors strongly affect tactile discrimination performance. Here, we show that non-informative vision of the touched body part influences tactile discrimination by modulating tactile RFs. Ten subjects performed spatial discrimination between touch locations on the forearm. Performance was improved when subjects saw their forearm compared to viewing a neutral object in the same location. The extent of visual information was relevant, since restricted view of the forearm did not have this enhancing effect. Vibrotactile maskers were placed symmetrically on either side of the tactile target locations, at two different distances. Overall, masking significantly impaired discrimination performance, but the spatial gradient of masking depended on what subjects viewed. Viewing the body reduced the effect of distant maskers, but enhanced the effect of close maskers, as compared to viewing a neutral object. We propose that viewing the body improves functional touch by sharpening tactile RFs in an early somatosensory map. Top-down modulation of lateral inhibition could underlie these effects.

In-street wind direction variability in the vicinity of a busy intersection in central London

We present results from fast-response wind measurements within and above a busy intersection between two street canyons (Marylebone Road and Gloucester Place) in Westminster, London taken as part of the DAPPLE (Dispersion of Air Pollution and Penetration into the Local Environment; www.dapple.org.uk) 2007 field campaign. The data reported here were collected using ultrasonic anemometers on the roof-top of a building adjacent to the intersection and at two heights on a pair of lamp-posts on opposite sides of the intersection. Site characteristics, data analysis and the variation of intersection flow with the above-roof wind direction (θref) are discussed. Evidence of both flow channelling and recirculation was identified within the canyon, only a few metres from the intersection for along-street and across-street roof-top winds respectively. Results also indicate that for oblique rooftop flows, the intersection flow is a complex combination of bifurcated channelled flows, recirculation and corner vortices. Asymmetries in local building geometry around the intersection and small changes in the background wind direction (changes in 15-min mean θref of 5–10 degrees) were also observed to have profound influences on the behaviour of intersection flow patterns. Consequently, short time-scale variability in the background flow direction can lead to highly scattered in-street mean flow angles masking the true multi-modal features of the flow and thus further complicating modelling challenges.

The neural processing of masked speech: Evidence for different mechanisms in the left and right temporal lobes

It has been previously demonstrated that extensive activation in the dorsolateral temporal lobes associated with masking a speech target with a speech masker, consistent with the hypothesis that competition for central auditory processes is an important factor in informational masking. Here, masking from speech and two additional maskers derived from the original speech were investigated. One of these is spectrally rotated speech, which is unintelligible and has a similar (inverted) spectrotemporal profile to speech. The authors also controlled for the possibility of “glimpsing” of the target signal during modulated masking sounds by using speech-modulated noise as a masker in a baseline condition. Functional imaging results reveal that masking speech with speech leads to bilateral superior temporal gyrus (STG) activation relative to a speech-in-noise baseline, while masking speech with spectrally rotated speech leads solely to right STG activation relative to the baseline. This result is discussed in terms of hemispheric asymmetries for speech perception, and interpreted as showing that masking effects can arise through two parallel neural systems, in the left and right temporal lobes. This has implications for the competition for resources caused by speech and rotated speech maskers, and may illuminate some of the mechanisms involved in informational masking.

The effects of non-host plant essential oil volatiles on the behaviour of the pollen beetle Meligethes aeneus

The use of semiochemicals for manipulation of the pollen beetle Meligethes aeneus (Fabricius) (Coleoptera: Nitidulidae) is being investigated for potential incorporation into a push-pull control strategy for this pest, which damages oilseed rape, Brassica napus L. (Brassicaceae), throughout Europe. The response of M. aeneus to non-host plant volatiles was investigated in laboratory assays to establish whether they have any effect on host plant location behaviour. Two approaches were used. First a novel, moving-air bioassay using air funnels was developed to compare the response of M. aeneus to several non-host plant essential oils. The beetles avoided the host plant flowers in the presence of non-host volatiles, suggesting that M. aeneus uses olfactory cues in host location and/or acceptance. The results were expressed as 'repellency values' in order to compare the effects of the different oils tested. Lavender (Lavendula angustifolia Miller) (Lamiaceae) essential oil gave the highest repellency value. In addition, a four-arm olfactometer was used to investigate olfactory responses, as this technique eliminated the influence of host plant visual and contact cues. The attraction to host plant volatiles was reduced by the addition of non-host plant volatiles, but in addition to masking the host plant volatiles, the non-host volatiles were avoided when these were presented alone. This is encouraging for the potential use of non-host plants within a push-pull strategy to reduce the pest colonisation of crops. Further testing in more realistic semi-field and field trials is underway.

Models, mathematics and meaning in interdisciplinary research

Interdisciplinary research presents particular challenges for unambiguous communication. Frequently, the meanings of words differ markedly between disciplines, leading to apparent consensus masking fundamental misunderstandings. Researchers can agree on the need for models, but conceive of models fundamentally differently. While mathematics is frequently seen as an elitist language reinforcing disciplinary distinctions, both mathematics and modelling can also offer scope to bridge disciplinary epistemological divisions and create common ground on which very different disciplines can meet. This paper reflects on the role and scope for mathematics and modelling to present a common epistemological space in interdisciplinary research spanning the social, natural and engineering sciences.