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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
251

以灰區間數修正模糊層級分析法下專家意見評估模式進行供應商選擇 / Use Grey Interval Number to Revise FAHP Method in Vendor Selection Process

蘇家弘, Su,Chia-Hung Unknown Date (has links)
本研究主要目的為透過灰色區間數的概念,利用其解決小樣本不確定問題的特性,修正在模糊層級分析法 (Fuzzy Analytic Hierarchy Process, FAHP) 下專家 (評估小組) 意見回饋時的不確定因素來進行供應商評選,使專家 (評估小組) 在進行指標或構面間比較時,能夠反映最真實的意見。 研究方法以模糊層級分析法為基礎進行供應商選擇,藉由模糊數概念解決舊有分析層級程序法中主觀及不精確的問題,並透過灰色區間數的概念,利用其解決小樣本不確定問題的特性,解決在進行模糊層級分析過程時,評選人員數量少而導至意見回饋樣本數較少,難以估算的問題;或評估人員對於語意尺度認知不明確,而成意見回饋時的不精確,避免因為這些原因,造成評估結果不準確,導至決策的偏差。 透過專家 (評估小組) 針對需求擬定參考構面及構面下的指標,利用層級的結構,將其做有系統的連結,透過專家 (評估小組) 針對各構面及各構面下指標間的強弱依據的回答,依此結果進行分析層級程序法的計算,找出各構面及各構面下指標間權重,進行供應商評選。 本研究實驗設計假設情境為在MTO生產流程下,透過系統動態學建構流程模型,模擬製造商生產運作。另外再設立專家意見實驗組及對照組,藉由同組評估小組填答不同意見所得的權重,加乘模擬所產生的供應商基本資料轉換為相對強度得分,進行研究方法運算,再比對模擬產生之績效結果,驗證所選供應商績效的確是最佳,驗證本研究所提出之選商方法確實有效。 / In the environment of globalization, the cooperation between enterprises and the suppliers has changed closeness into diversity. How to look for the best supplier in the use of objectivity in order to meet the need of product becomes very important. Nowadays, every industry aims at the international and various developments. Materials that consist in a product may come from every corners of the world; in that case, we have more choices in picking the suitable copartner. However, the standard of the suppliers has a big influence in the production quality. This research based on Fuzzy Analytic Hierarchy Process (FAHP) use to supplier selection. Use fuzzy number to solve the problems about subjective and imprecise in Analytic Hierarchy Process (AHP). And solve the problem about small sample and uncertain situation, sometimes come about who can’t clearly understand the meaning about item to choice, during jury making decision by Grey Interval Numbers. This situation may bring about incorrect results and wrong decision. This research makes a case under the MTO (make-to-order) producing process by SCOR model. Build the System Dynamic process model to simulate the supplier’s production process. And there have two different questionnaires result every different item’s weight. Herewith prove using this research method to select supplier is feasible and efficacious. Based on the evaluation criteria of need, we hope that enterprises can make an objective and correct decision in choosing the appropriate supplier.
252

環境與自然資源經濟的三個議題 / Three Essays on Environmental and Natural Resource Economics

洪志銘, Hung,Chih-Ming Unknown Date (has links)
本論文由三篇文章所構成。第二章主要針對參考點(reference points)的選擇問題。在綠色國民所得帳中,選擇哪個參考點作為扣除環境質損與自然資源折耗是很重要的。由於既有文獻中的參考點選擇大多過於極端,本文遂針對文獻上的缺失,建議以法定的環保標準做為參考點,使得環境質損、環境效益、自然資源折耗與服務都可顯示出來。 第三章則以台灣的烏魚業為對象,以不合作賽局分析大陸漁民在烏魚迴游路徑上捕魚以及溫室效應對台灣漁業及消費者造成的影響。 第四章則指出Huang and Cai (1994)一文在理論模型設計上的問題,並提出改正,以使其論點獲得支持。 / This dissertation is made up of three essays that address the issues of green net national product, renewable resources and pollution externalities. In Chapter 2, the issue of choosing reference points is discussed. The reference point is a key parameter for estimating the values of environmental degradation and natural resource depletion that are used to adjust the Net National Product. Most of the reference points used in the literature are extreme points in the spectrum of environmental quality and may thus result in estimated values of degradation and depletion that are not consistent with the standard theory of environmental economics. In this chapter, we argue that by using clearly defined standards as reference points, e.g., environmental quality standards, for managing environmental quality and natural resources, correct values of environmental degradation and services, and natural resource depletion and direct nature services, as well as green NNP can emerge. In Chapter 3, we examine the problem of non-cooperative fishing between Mainland China (MC) and Taiwan (TW) as well as the effects of rising sea surface temperature (SST) on the grey mullet fishery. By setting the three stages of the non-cooperative game, it is shown that the expansion of the fleets in MC and the rising SST cause the rent obtained from the TW fishery to decline, and that Taiwan may partially offset such an adverse effect by adjusting its fleet size. This essay also shows that Taiwan can expand its fleet to a greater extent when facing an imperfectly elastic demand for fish than when facing a perfectly elastic demand. In addition, when consumer welfare is included in the determination of the size of the fleet, fleet size can expand more than when profit is considered alone. In Chapter 4, we point out the problems in Huang and Cai (1994) that arise from the absence of a “pollution externality.” We modify their model by introducing the emission tax and find that it supports Huang and Cai (1994)’s claim that the share of private abatement expenditure is constant at all times, a claim that is criticized by Shieh, et al. (2001).
253

Properties of Volume Bragg Gratings and Nonlinear Crystals for Laser Engineering

Tjörnhammar, Staffan January 2015 (has links)
This thesis focuses on two topics: thermal limitations of volume Bragg gratings (VBGs) employed as laser-cavity mirrors and formation of color centers in KTiOPO4 and its isomorphs. To explore the mechanisms of the thermal limitations of VBGs in high power lasers, I designed and constructed a diode-pumped, solid‑state laser with a VBG as cavity mirror that had a significantly higher absorption than what is typical. Thereby I could study the limiting thermal effects by using only moderate intra-cavity power. Additionally, I designed a computer model to numerically investigate the thermal effects in VBGs. Both the experiments and the simulations showed that the laser became successively more unstable when the power was increased. Absorption of the reflected laser beam causes broadening of the grating spectrum accompanied by decreasing diffraction efficiency. The reduced reflectivity leads to a leakage of the radiation through the grating. Moreover, the simulations showed that this increased instability was due to a reshaping of the intensity distribution profile inside the grating, which, in turn, leads to a sharp reduction of the diffraction efficiency. High-intensity visible radiation induces color centers in KTiOPO4, which can lead to severe decrease in the performance of the crystal and can cause catastrophic breakdown. The formation of color centers was investigated by measuring picosecond, blue-light induced infrared absorption (BLIIRA) in periodically-poled KTiOPO4, Rb:KTiOPO4, RbTiOPO4, KTiOAsO4 and RbTiOAsO4 through thermal lens spectroscopy using a common-path interferometer. This setup is capable of measuring absorption as low as 10-5 cm-1. The dependence of the BLIIRA signal on blue light average power and intensity as well as on the crystal temperature was studied. The results show the presence of at least two different types of color centers. A higher level of remnant absorption was observed in the phosphates compared to that of the arsenates. The largest portion of the induced absorption is attributed to photo-generated electrons and holes being self-trapped in the proximity to the Ti4+ and O2- ions, respectively, forming polaron color centers. Stabilization of these centers is aided by the presence of mobile alkali metal vacancies in the crystal. / Denna avhandling fokuserar på både volymbraggitters (VBGs) termiska begränsningar, i tillämpning som speglar i laserkaviteter, och på bildandet av färgcentra i KTiOPO4 och isomorfa kristaller. För att undersöka de termiska effekterna i VBGer som medför begränsningar på högeffektlasrar utfördes både experiment och simuleringar. För experimenten konstruerades en diod-pumpad Yb:KYW laser med ett VBG som har betydligt högre absorption än vad som är typiskt. Därmed kunde de termiska effekterna studeras vid måttliga intrakavitetseffekter. Simuleringarna bestod av två delmodeller; gitterstrukturen modelerades med överföringsmatriser och värmeflödet med en tredimensionell modell baserad på finita elementmetoden. Både experimenten och simuleringarna visade att en laser blir successivt mer instabil när den optiska effekten ökar. Absorptionen av laserstrålen i VBGt förändrade dess spektrala egenskaper, vilket i sin tur påverkade laserns stabilitet och prestanda. De huvudsakliga effekterna var en breddning av gittrets spektrum med en minskad reflektans. Simuleringarna visade även att den ökade instabiliteten berodde på en förändring av strålningens intensitetsfördelning inuti gittret, vilket accelererade reduktionen av gittrets reflekterande förmåga. I termer av den effekt som faller in mot gittret, har lasern en tydlig övre effektgräns. När den gränsen har uppnåtts leder vidare ökning av pumpeffekten i huvudsak till ökat läckage genom volymbraggittret, i stället för till ökad uteffekt hos laserstrålen. Kortvågigt synlig ljus av hög intensitet inducerar färgcentra i KTiOPO4, vilket kan leda till kraftigt reducerad transparens och kan orsaka permanent skada i kristallen. För att undersöka skapandet av dessa färgcentra mättes den termiska lins som uppstår vid blå-ljus-inducerad infraröd absorption (Eng: blue-light induced infrared absorption = BLIIRA) inducerad av blåa laserpulser vid en våglängd av 398 nm och vid pulslängder i storlek av pikosekunder i periodiskt‑polad KTiOPO4, Rb:KTiOPO4, RbTiOPO4, KTiOAsO4 och RbTiOAsO4. Den termiska linsen mättes med en metod kallad gemensam-vägsträcka-interferometer (Eng: common-path interferometer), en metod känslig nog för att mäta absorption så låg som 10-5 cm-1. Dessutom undersöktes hur nivån av BLIIRA beror på medeleffekten och intensiteten hos den blåa laserstrålen samt på kristalltemperaturen. Resultaten visar att det bildas minst två typer av färgcentra med olika livslängder. Vidare observerades en högre grad av långsamt avklingande absorption i fosfaterna jämfört med arsenaterna. Den största delen av den inducerade absorptionen tillskrivs fotogenererade elektroner och hål som ”självfångas” i närheten av Ti4+ respektive O2- joner, och bildar färgcentra av polaron karaktär. Stabilisering av dessa centra underlättas av lättrörliga alkalivakanser i kristallerna. / <p>QC 20150922</p>
254

Housing alternatives in the single family neighbourhood

Harth, Mia 05 1900 (has links)
The single family neighbourhood is a favoured residential form, yet this low density residential option is unsustainable. With its high consumption of land and services, the continued development of the traditional single family neighbourhood results in urban sprawl and inefficient use of infrastructure. In addition, zoning regulations that prescribe large lot sizes, deep setbacks and singleuses, create disconnected, mono-functional residential enclaves. Residential intensification is increasingly touted by urban theorists and proponents of sustainable development as part of the solution. This involves focussing new development on underutilized land, which in turn necessitates the acceptance of new housing forms within existing neighbourhoods. However, people are often wary of higher densities and alternative housing options, believing that the qualities of livability that they identify with the single family neighbourhood are threatened. Focussing on ground-oriented residential alternatives, this project examines the key elements that comprise the residential environment and their connection to aspects of livability. A set of guidelines based on principles of sustainable development directs the design for a higher density, environmentally responsive, groundoriented residential development on an infill lot in an existing single family neighbourhood. The final design proposes the division of the single site into five developable lots, introduces four different dwelling types, and integrates into the landscape a stormwater management system. The plan is compared to other similar alternative developments.
255

Automated Ice-Water Classification using Dual Polarization SAR Imagery

Leigh, Steve January 2013 (has links)
Mapping ice and open water in ocean bodies is important for numerous purposes including environmental analysis and ship navigation. The Canadian Ice Service (CIS) currently has several expert ice analysts manually generate ice maps on a daily basis. The CIS would like to augment their current process with an automated ice-water discrimination algorithm capable of operating on dual-pol synthetic aperture radar (SAR) images produced by RADARSAT-2. Automated methods can provide mappings in larger volumes, with more consistency, and in finer resolutions that are otherwise impractical to generate. We have developed such an automated ice-water discrimination system called MAGIC. The algorithm first classifies the HV scene using the glocal method, a hierarchical region-based classification method. The glocal method incorporates spatial context information into the classification model using a modified watershed segmentation and a previously developed MRF classification algorithm called IRGS. Second, a pixel-based support vector machine (SVM) using a nonlinear RBF kernel classification is performed exploiting SAR grey-level co-occurrence matrix (GLCM) texture and backscatter features. Finally, the IRGS and SVM classification results are combined using the IRGS approach but with a modified energy function to accommodate the SVM pixel-based information. The combined classifier was tested on 61 ground truthed dual-pol RADARSAT-2 scenes of the Beaufort Sea containing a variety of ice types and water patterns across melt, summer, and freeze-up periods. The average leave-one-out classification accuracy with respect to these ground truths is 95.8% and MAGIC attains an accuracy of 90% or above on 88% of the scenes. The MAGIC system is now under consideration by CIS for operational use.
256

BIOLOGY, EPIDEMIOLOGY AND MODELLING OF BOTRYTIS CINEREA PERS.:FR., THE CAUSAL AGENT OF GREY MOULD IN GRAPEVINE

CILIBERTI, NICOLA 28 January 2015 (has links)
Gli obbiettivi di questa tesi di dottorato erano: i) valutare l’effetto di differenti condizioni ambientali sulla biologia ed epidemiologia di isolati di B. cinerea appartenenti alle sub-popolazioni transposa e vacuma, e ii) sviluppare un nuovo modello previsionale per predire il rischio di muffa grigia nei vigneti tra le fasi fenologiche di sviluppo delle infiorescenze e maturazione dei grappoli. Gli effetti della temperatura, durata di bagnatura e umidità relativa sulle infezioni di infiorescenze e bacche di Vitis vinifera sono stati valutati con inoculazioni artificiali di isolati di B. cinerea. Gli effetti della temperatura, attività dell’acqua, umidità relativa e composizione delle bacche di uva sulla germinazione dei conidi, crescita miceliale e produzione di conidi sono stati valutati su substrati artificiali. I risultati evidenziano che la capacità di causare infezioni varia con gli isolati indipendentemente dall’appartenenza alle sub-popolazioni transposa o vacuma. Inoltre, le risposte dei differenti isolati al variare delle condizioni ambientali risultano essere simili. Basandosi sui risultati ottenuti sono state sviluppate equazioni matematiche per spiegare l’effetto dei fattori ambientali sull’incidenza delle infezioni di infiorescenze e bacche, germinazione dei conidi, crescita miceliale e produzione di conidi. Un nuovo modello previsionale è stato sviluppato per predire le infezioni di Botrytis cinerea nei vigneti utilizzando le equazioni sviluppate e seguendo un approccio meccanicistico. Il modello è stato validato per 6 anni (2009-2014) in 13 vigneti localizzati in Italia e Francia. Il nuovo modello risulta essere più completo di quelli proposti finora in letteratura e può essere utilizzato per migliorare le strategie di controllo della muffa grigia nei vigneti. / The aims of this Doctoral work were: i) to investigate the effect of different environmental conditions on biology and epidemiology of B. cinerea strains belonging the two transposon types vacuma and transposa, and ii) develop a new weather-driven mechanistic model in order to predict risk of grey mould in vineyards from early growth of inflorescences to berry ripening. The effect of temperature, wetness duration and relative humidity on infection of Vitis vinifera inflorescences and berries was investigated by artificial inoculation of B. cinerea strains. The effect of temperature, water activity, relative humidity and grape berry composition on conidia germination, colony growth and conidial production was investigated in agar-medium. The results showed that the ability to cause infection was a strain rather than a transposon genotype attribute. Moreover, the general response to different environmental conditions is similar among different B. cinerea strains. Based on these data, equations were developed to account the combined effects of environmental factors on infection incidence, conidia germination, colony growth and conidial production. A new previsional model for Botrytis cinerea infections on grapevine was elaborated using the equations developed and following a mechanistic approach. The model was validated over a 6-year period (2009 to 2014) in 13 vineyards located in different grape-growing areas of Italy and France. The model is more complete than the others proposed in literature and represents an improvement to control grey mould in vineyards.
257

Calculation of Physical Processes at the LHC

Al-Binni, Usama Adnan 01 December 2011 (has links)
With the start of the age of the Large Hadron Collider (LHC) two challenges face theoreticians and computational physicists. The first is about understanding theories beyond the Standard Model and producing verifiable predictions that can be tested against what the LHC and subsequent machines would produce. The second is to improve computational methods so that the new experimental precision is matched by a theoretical one. But this improvement is also crucial for the detection of potential deviations from Standard Model predictions and possibly also finding the elusive Higgs. This work tries to address problems in both areas. In the first part we study the effects of adding tension in considering a black-hole on a brane. Such black-holes are predicted by some models as potential phenomena at the LHC. We calculate the effects of adding tension on observable quantities of black-holes, namely, quasinormal mode frequencies and Hawking radiation, and we show how this improves predictions. In the second part we investigate the computational problem of extending the Britto-Cachazo-Feng-Witten (BCFW) method to 1-loop level. The BCFW has been successfully used in recent years to compute scattering amplitudes at tree-level by suitably complex-shifting external momenta and reducing diagrams to simpler ones. In our investigation we establish that the BCFW can be extended to 1-loop, which means that 1-loop integrands can be treated as trees and can be broken down further into even simpler trees using the BCFW. We explicitly look at the effects of the shift for the lowest three n-point cases, but also demonstrate how the result extends to arbitrary n.
258

Photocatalysis with a Heterosupramolecular Assembly

Wilson, Gregory J. January 2006 (has links)
Supramolecular chemistry has asserted itself as a significant multidisciplinary field concerned with molecular effects afforded through non-covalent molecular interactions. The increased interest in the literature towards nanoscale devices, through modulation of molecular function, has seen the renaissance of supramolecular chemistry as function progresses from solution to surface. Heterosupramolecular chemistry follows the architectural principles of supramolecular chemistry and embraces both covalent and non-covalent interactions of condensed phase surfaces and molecular components. A modular approach to device architecture was applied as a novel method of performing photocatalysis under visible light illumination. The application of heterosupramolecular assembly to the design of photoelectrochemical cells capable of visible light induced charge separation allowed the study of interfacial processes by means of electrochemical observations. Preparation of a series of supramolecular components was undertaken as specific molecular species within a photochemical system. Starting from a synthesised bidentate ligand that incorporated an acidic functional group, 4,4'-bis(methyl)phosphonate-2,2'-bipyridine (dmpbpy) as its ethyl ester, was chelated to give the surface sensitisers, bis-(2,2'-bipyridine)-(4,4'-bis(methyl)phosphonato-2,2'-bipyridine)ruthenium(II) dichloride ([Ru(bpy)2(dmpbpy)]Cl2) and cis-bis-(4,4'-bis-(methyl)phosphonato-2,2'-bipyridine)(2,2'-bipyridine)ruthenium(II) dichloride ([Ru(dmpbpy)2(bpy)]Cl2). An electron relay moiety with an acidic functional group, 1-ethyl-1'-(2-phosphonoethyl)-4,4'-bipyridinium dichloride (EVP), was also prepared using a procedure developed by the candidate. The electronic properties of the prepared photosensitisers were examined by theoretical quantum chemical TD-DFT calculations on the molecular structures and singlet excitations were discussed in relation to experimental data. This identified that the lowest lying LUMO states were consistently occupied by 2,2'-bipyridine (bpy) and this was speculated to be a factor affecting quantum injection yields. The effect of microwave modification of colloidal TiO2 suspensions under extended periods of treatment was investigated. Nanoparticles of TiO2 were compared and contrast to similar convection hydrothermally treated TiO2 and a commercial titania product, namely Degussa P25, both of which are utilised in device fabrication. The investigation identified that extended periods of microwave hydrothermal treatment do not greatly enhance the crystallinity and primary grain size of TiO2. The heterosupramolecular assembly of a multi-component photochemical system was constructed from prepared molecular and condensed phase components. It was demonstrated that this device was capable of inducing a photochemical reaction in H2O under irradiation with  > 420 nm in the absence of an organic electron donor. Interpretation of the photocurrents obtained from this assembly provided understanding of photochemical reactions under low light intensities. Optimised conditions for the photochemical reaction was determined to be pH = 5 and illumination yielded = 0.0036% with an apparent quantum yield (AQY) = 1.6%. Photocatalytic decomposition of organic compounds in a dye-sensitised photoelectrocatalytic cell was investigated for the complete mineralisation of EDTA into CO2, H2 and simple amines and interpreted through photocurrent observations. This was extended to a broad range of organic compounds of various solution concentrations as a simulated industrial waste stream. Photooxidation gave unique photocurrent-time profiles which identified two distinct interfacial processes by mathematical treatment of photocurrent transients with a kinetic model. Kinetic parameters were proposed as a factor for qualitative discrimination of the organic compounds. The implications of these results for heterogeneous catalysis were discussed and the formation of Host-Guest complexes as a method of molecular sensing and as specific photocatalytic receptors was proposed.
259

A longitudinal study of brain structure in the early stages of schizophrenia

Whitford, Thomas James January 2007 (has links)
Doctor of Philosophy (PhD) / Schizophrenia is a severe mental illness that affects approximately 1% of the population worldwide, and which typically has a devastating effect on the lives of its sufferers. The characteristic symptoms of the disease include hallucinations, delusions, disorganized thought and reduced emotional expression. While many of the early theories of schizophrenia focused on its psychosocial foundations, more recent theories have focused on the neurobiological underpinnings of the disease. This thesis has four primary aims: 1) to use magnetic resonance imaging (MRI) to identify the structural brain abnormalities present in patients suffering from their first episode of schizophrenia (FES), 2) to elucidate whether these abnormalities were static or progressive over the first 2-3 years of patients’ illness, 3) to identify the relationship between these neuroanatomical abnormalities and patients’ clinical profile, and 4) to identify the normative relationship between longitudinal changes in neuroanatomy and electrophysiology in healthy participants, and to compare this to the relationship observed between these two indices in patients with FES. The aim of Chapter 2 was to use MRI to identify the neuroanatomical changes that occur over adolescence in healthy participants, and to identify the normative relationship between the neuroanatomical changes and electrophysiological changes associated with healthy periadolescent brain maturation. MRI and electroencephalographic (EEG) scans were acquired from 138 healthy participants between the ages of 10 and 30 years. The MRI scans were segmented into grey matter (GM) and white matter (WM) images, before being parcellated into the frontal, temporal, parietal and occipital lobes. Absolute EEG power was calculated for the slow-wave, alpha and beta frequency bands, for the corresponding cortical regions. The age-related changes in regional tissue volumes and regional EEG power were inferred with a regression model. The results indicated that the healthy participants experienced accelerated GM loss, EEG power loss and WM gain in the frontal and parietal lobes between the ages of 10 and 20 years, which decelerated between the ages of 20 and 30 years. A linear relationship was also observed between the maturational changes in regional GM volumes and EEG power in the frontal and parietal lobes. These results indicate that the periadolescent period is a time of great structural and electrophysiological change in the healthy human brain. The aim of Chapter 3 was to identify the GM abnormalities present in patients with FES, both at the time of their first presentation to mental health services (baseline), and over the first 2-3 years of their illness (follow-up). MRI scans were acquired from 41 patients with FES at baseline, and 47 matched healthy control subjects. Of these participants, 25 FES patients and 26 controls returned 2-3 years later for a follow-up scan. The analysis technique of voxel-based morphometry (VBM) was used in conjunction with the Statistical Parametric Mapping (SPM) software package in order to identify the regions of GM difference between the groups at baseline. The related analysis technique of tensor-based morphometry (TBM) was used to identify subjects’ longitudinal GM change over the follow-up interval. Relative to the healthy controls, the FES patients were observed to exhibit widespread GM reductions in the frontal, parietal and temporal cortices and cerebellum at baseline, as well as more circumscribed regions of GM increase, particularly in the occipital lobe. Furthermore, the FES patients lost considerably more GM over the follow-up interval than the controls, particularly in the parietal and temporal cortices. These results indicate that patients with FES exhibit significant structural brain abnormalities very early in the course of their illness, and that these abnormalities progress over the first few years of their illness. Chapter 4 employed the same methodology to investigate the white matter abnormalities exhibited by the FES subjects relative to the controls, both at baseline and over the follow-up interval. Compared to controls, the FES patients exhibited volumetric WM deficits in the frontal and temporal lobes at baseline, as well as volumetric increases at the fronto-parietal junction bilaterally. Furthermore, the FES patients lost considerably more WM over the follow-up interval than did the controls in the middle and inferior temporal cortex bilaterally. While there is substantial evidence indicating that abnormalities in the maturational processes of myelination play a significant role in the development of WM abnormalities in FES, the observed longitudinal reductions in WM were consistent with the death of a select population of temporal lobe neurons over the follow-up interval. The aim of Chapter 5 was to investigate the clinical correlates of the GM abnormalities exhibited by the FES patients at baseline. The volumes of four distinct cerebral regions where 31 patients with FES exhibited reduced GM volumes relative to 30 matched controls were calculated and correlated with patients’ scores on three primary symptom dimensions: Disorganization, Reality Distortion and Psychomotor Poverty. The results indicated that the greater the degree of atrophy exhibited by the FES patients in three of these four ‘regions-of-reduction’, the less severe their degree of Reality Distortion. These results suggest that an excessive amount of GM atrophy may in fact preclude the formation of hallucinations or highly systematized delusions in patients with FES. The aim of Chapter 6 was to identify the relationship between the longitudinal changes in brain structure and brain electrophysiology exhibited by 19 FES patients over the first 2-3 years of their illness, and to compare it to the normative relationship between the two indices reported in Chapter 2. The methodology employed for the parcellation of the MRI and EEG data was identical to Chapter 2. The results indicated that, in contrast to the healthy controls, the longitudinal reduction in GM volume exhibited by the FES patients was not associated with a corresponding reduction in EEG power in any brain lobe. In contrast, EEG power was observed to be maintained or even to increase over the follow-up interval in these patients. These results were consistent with the FES patients experiencing an abnormal elevation of neural synchrony. Such an abnormality in neural synchrony could potentially form the basis of the dysfunctional neural connectivity that has been widely proposed to underlie the functional deficits present in patients with schizophrenia. The primary aim of Chapter 7 was to assimilate the findings from the preceding empirical chapters with the theoretical framework provided in the literature, into an integrated and testable model of schizophrenia. The model emphasized dysfunctions in brain maturation, specifically in the normative processes of synaptic ‘pruning’ and axonal myelination, as playing a key role in the development of disintegrated neural activity and the subsequent onset of schizophrenic symptoms. The model concluded with the novel proposal that disintegrated neural activity arises from abnormal elevations in the synchrony of synaptic activity in patients with first-episode schizophrenia.
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Preserving trees

Skead, C J (Cuthbert John) 19 May 1959 (has links)
Article written by C. J. Skead to the East London Daily Dispatch (dated 19 May 1959), bringing attention to the deforestation of the Fort Grey forest by Mr C Miles Warren (MP). The article is acompanied by a harndwitten note stating "Mr C Miles Warren, M.P. had the contract for removing the forest and did very well out of it, especially with box-wood!! Hence the letter which would have [illegible] his consumers".

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