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Severe Changes (severe + change)
Selected AbstractsStudying the effects of Mahonia aquifolium populations on small-scale mountain agro-ecosystems in Hungary with the view to minimise land degradationLAND DEGRADATION AND DEVELOPMENT, Issue 3 2009C. Hudek Abstract After the political changeover in Hungary in 1989, many farm owners faced problems typical of a small sized farm (<1,ha) as well as a lack of various resources. This led to many farms with great horticultural backgrounds being abandoned, especially in mountainous areas where erosion control is essential for soil conservation. Severe changes can occur on soil through property abandonment. The local socio-economic aspects must be taken into consideration as well as the problem of soil degradation as this will be a motivating factor in preservation initiatives. Under horticultural management, Mahonia aquifolium was tested to determine its efficiency in water erosion control in mountainous conditions in Hungary. Soil loss and water runoff were measured after every rainfall event at six different plots: four cultivated M. aquifolium populations with different ages (4, 12, 20 and 25 years old) and two control plots. A bare soil field and a grass field represented the control plots. The results show that as the age of the M. aquifolium populations increase, the cumulative runoff and sediment values decrease. It also showed that 2 years after setting up a new M. aquifolium plantation, the cumulative runoff decreased by 69 per cent and the cumulative soil loss decreased by 74 per cent. This indicates that a M. aquifolium population could play a significant role in erosion control within a short period of time. Copyright © 2009 John Wiley & Sons, Ltd. [source] Essential role of the V-ATPase in male gametophyte developmentTHE PLANT JOURNAL, Issue 1 2005Jan Dettmer Summary Intracellular pH homeostasis is a prerequisite for biological processes and requires the action of proton pumps. The vacuolar H+ -ATPase (V-ATPase) is involved in regulating pH in endomembrane compartments of all eukaryotic cells. In plants, there is an additional endomembrane proton pump, H+ -pyrophosphatase (H+ -PPase). However, the relative roles of the two types of pumps in endomembrane acidification and energization of secondary active transport are unclear. Here, we show that a strong T-DNA insertion allele of VHA-A, the single copy gene encoding the catalytic subunit of the Arabidopsis V-ATPase, causes complete male and partial female gametophytic lethality. Severe changes in the morphology of Golgi stacks and Golgi-derived vesicles in male gametophytes are the first visible symptoms of cell degeneration leading to a failure to develop mature pollen. Similar effects on Golgi morphology were observed in pollen tubes when growth was blocked by Concanamycin A, a specific V-ATPase inhibitor. Taken together, our results suggests that V-ATPase function is essential for Golgi organization and development of the male gametophyte. [source] The mouse MPTP model: gene expression changes in dopaminergic neuronsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 1 2003Kati Kühn Abstract Parkinson's disease (PD) is a common neurodegenerative disorder, characterized by the progressive loss of dopaminergic neurons in the substantia nigra. Although valuable animal models have been developed, our knowledge of the aetiology and pathogenic factors implicated in PD is still insufficient to develop causal therapeutic strategies aimed at halting its progression. The neurotoxicity induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) is one of the most valuable models for analysing pathological aspects of PD. In this paper we studied the gene expression patterns underlying the pathogenesis of MPTP-induced neurodegeneration. We treated young and old C57BL/6 mice with different schedules of MPTP to induce degenerative processes that vary in intensity and time-course. During the first week after intoxication we used nonradioactive in situ -hybridization to investigate the expression patterns of genes associated with (i) dopamine metabolism and signalling; (ii) familial forms of PD; (iii) protein folding and (iv) energy metabolism. MPTP injections induced different severities of neuronal injury depending on the age of the animals and the schedule of administration as well as a significant degeneration in the striatum. In situ hybridization showed that MPTP intoxication initiated a number of gene expression changes that (i) were restricted to the neurons of the substantia nigra pars compacta; (ii) were correlated in intensity and number of changes with the age of the animals and the severity of histopathological disturbances; (iii) displayed in each a significant down-regulation by the end of one week after the last MPTP injection, but (iv) varied within one MPTP regimen in expression levels during the observation period. The subacute injection of MPTP into one-year-old mice induced the most severe changes in gene expression. All genes investigated were affected. However, ,-synuclein was the only gene that was exclusively up-regulated in MPTP-treated animals displaying cell death. [source] Changes in surface roughness and colour stability of soft denture lining materials caused by denture cleansersJOURNAL OF ORAL REHABILITATION, Issue 2 2003C. Jin summary, Soft denture lining materials were immersed into solutions of denture cleansers for 8 h at room temperature, and immersed into distilled water for the remainder of the 24-h period at 37 °C. Surface roughness of the soft denture lining materials was measured by contact type surface roughness instrument. For the colour stability test, soft denture lining materials were immersed in the denture cleansers as described above for 180 days. Finally, the colour changes of each material were quantitatively measured by a photometrical instrument to obtain the colour differences between newly processed specimen and immersed specimens (P < 0·01). An autopolymerizing silicone material, Evatouch, exhibited severe changes in surface roughness by all denture cleanser, and the generic material GC Denture Relining showed the minimal changes. Severe colour changes were also observed with some liner and cleanser combinations (P < 0·01). Except for Evatouth, the four silicone soft liners were more stable in surface roughness and in colour change than the two acrylic soft liners. One autopolymerizing silicone (GC denture relining) and one heat curing silicone (Molloplast B) demonstrated the best stability. [source] Amelioration of disease severity by intraarticular hylan therapy in bilateral canine osteoarthritisJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 3 2000K. W. Marshall Because of its high molecular weight, the glycosaminoglycan molecule hyaluronan is responsible for the viscoelastic properties of normal synovial fluid. In osteoarthritis, the concentration and molecular weight of hyaluronan in synovial fluid is diminished; this impairs the ability of synovial fluid to effectively lubricate joints, absorb loads, and exert anti-inflammatory effects. Using a bilateral anterior cruciateligament transection and partial neurectomy canine model of osteoarthritis, this study examined the effect of viscosupplementation with hylan G-F 20 as a treatment for osteoarthritis, this study examined the effect of viscosupplementation with hylan G-F 20 as a treatment for osteoarthritis. Twelve dogs underwent bilateral arthroscopic anterior cruciate-ligament transections and partial neurectomy of the knee joints. Beginning 1 week after the operation, six dogs received three weekly 500-,l injections of hylan G-F 20 in one knee and a sham injection of saline solution in the contralateral knee (early-treatment group). The remaining six animals underwent the same treatment 2 months following the procedure (late-treatment group). All dogs were killed at 8 months, and both knees were evaluated for gross pathology, histology, and proteoglycan content. In addition, with use of 500-MHz [1H] magnetic resonance spectroscopy, the synovial fluid from both knees was assessed for changes in metabolic profile. Differences in outcome were analyzed with paired t tests. Gross pathological and histological examination revealed significantly less severe changes of osteoarthritis in knees treated with hylan G-F 20 2 months after surgery than in the contralateral untreated knees. Magnetic resonance spectroscopy of the specimens in this late-treatment group showed significantly decreased glucose concentrations and significantly elevated isoleucine levels in the synovial fluid from knees treated with hylan G-F 20 compared with the controls. Previous magnetic resonance spectroscopy had shown that glucose concentrations increase with the onset of osteoarthritis and eventually diminish in end-stage osteoarthritis. The three injections of hylan were given after osteoarthritis was established, and the severity of the disease was ameliorated in the treated knees 6 months after treatment. This occurred although hylan G-F 20 is almost certainly cleared from joints by lymphatics within 4 weeks of injection, suggesting that hylan therapy can retard the progression of osteoarthritis for periods of time extending beyond the intraarticular residence time of the injected molecules and that hylan injections given at relatively early stages of osteoarthritis may have a chondroprotective effect. No changes in outcome were noted in the animals that received hylan G-F 20 immediately following surgery. [source] EFFECT OF LACTIC ACID AND LACTIC ACID BACTERIA TREATMENT ON MYOFIBRILLAR PROTEIN DEGRADATION AND DYNAMIC RHEOLOGY OF BEEFJOURNAL OF TEXTURE STUDIES, Issue 3 2007M. SIGNORINI ABSTRACT Lactic acid has been used as an efficient decontaminant in meats aimed for direct consumption or product fabrication. However, reports on the functionality of proteins extracted from lactic acid-treated meat are scattered. The objective of this work was to study the degradation and gelling ability of myofibrillar protein extracts obtained from beef treated with lactic acid of chemical and microbial origins, stored at 4 and 20C. The gelling ability was considerably reduced by lactic acid treatment as a result of protein denaturation in acid conditions at both storage temperatures. Scanning electron microscopy showed loose structures resulting in low penetration resistance and storage modulus. Treatments with lactic acid or lactic acid bacteria (LAB) had similar effect on tan,, affecting gel rigidity but not elasticity. Penetration in gels obtained from LAB-treated meat was highly correlated with myosin degradation. Lactobacillus carnis -treated meat produced compact gels with high penetration resistance and storage modulus, although the structure became looser with storage time. LAB treatment, although not as efficient as lactic acid as a meat preservative, is a milder process causing less severe changes in meat structure rheology. PRACTICAL APPLICATIONS The potential of lactic fermentation by selected strains is somewhat limited as compared to lactic acid preservation of meat substrates, regarding pH reduction and its consequence on pathogens and spoilage microorganism population reduction. However, lactic acid bacteria (LAB) treatments are milder; therefore, changes in protein structure and rheology are less severe. Lactic acid in its chemical form promotes protein changes, whereas LAB does not. As myofibrillar protein configuration is responsible for most meat functional properties, such as gel and emulsion formation, it is important that protein structure remains unchanged as much as possible. Using nonproteolytic strains, protein degradation can only be altered by endogenous or bacteria-produced enzymes, which can be inhibited by several means. Meat preservation by lactic fermentation with selected strains can be an alternative when keeping meat protein functional properties unaltered. [source] Stanley Fahn Lecture 2005: The staging procedure for the inclusion body pathology associated with sporadic Parkinson's disease reconsideredMOVEMENT DISORDERS, Issue 12 2006Heiko Braak MD Abstract The synucleinopathy known as sporadic Parkinson's disease (PD) is a multisystem disorder that severely damages predisposed nerve cell types in circumscribed regions of the human nervous system. A recent staging procedure for the inclusion body pathology associated with PD proposes that, in the brain, the pathological process (formation of proteinaceous intraneuronal Lewy bodies and Lewy neurites) begins at two sites and continues in a topographically predictable sequence in six stages, during which components of the olfactory, autonomic, limbic, and somatomotor systems become progressively involved. In stages 1 to 2, the Lewy body pathology is confined to the medulla oblongata/pontine tegmentum and anterior olfactory structures. In stages 3 to 4, the substantia nigra and other nuclei of the basal mid- and forebrain become the focus of initially subtle and, then, severe changes. During this phase, the illness probably becomes clinically manifest. In the final stages 5 to 6, the lesions appear in the neocortex. This cross-sectional study originally was performed on 168 autopsy cases using material from 69 incidental cases and 41 clinically diagnosed PD patients as well as 58 age- and gender-matched controls. Here, the staging hypothesis is critically reconsidered and discussed. © 2006 Movement Disorder Society [source] Package performance testing of dangerous goods in high-altitude shipmentsPACKAGING TECHNOLOGY AND SCIENCE, Issue 3 2003S. Paul Singh Abstract This paper discusses the impact of high-altitude shipments on package integrity. High-altitude shipments are encountered when trucks travel over high mountain passes or when cargo and feeder aircraft transport packages in non-pressurized or partially-pressurized cargo holds. Both these types of transport methods will result in severe changes in pressure as compared to packages being transported close to sea level. The testing of packages under these conditions is critical since package integrity may be compromised. The current shipping tests performed in test laboratories do not account for pressure changes and vibration together. This study showed that combination packages for dangerous goods and hazardous materials that are tested to existing UN, ICAO and US DOT requirements are limited, and can result in significant number of leaks. Testing under combined vibration and pressure changes is necessary. Copyright © 2003 John Wiley & Sons, Ltd. [source] International evidence on alternative models of the term structure of volatilitiesTHE JOURNAL OF FUTURES MARKETS, Issue 7 2009Antonio Díaz The term structure of instantaneous volatilities (TSV) of forward rates for different monetary areas (euro, U.S. dollar and British pound) is examined using daily data from at-the-money cap markets. During the sample period (two and a half years), the TSV experienced severe changes both in level and shape. Two new functional forms of the instantaneous volatility of forward rates are proposed and tested within the LIBOR Market Model framework. Two other alternatives are calibrated and used as benchmarks to test the accuracy of the new models. The two new models provide more flexibility to adequately calibrate the observed cap prices, although this improved accuracy in replicating cap prices produces some instability in parameter estimates. © 2009 Wiley Periodicals, Inc. Jrl Fut Mark 29:653,683, 2009 [source] What is the consequence of retinal detachment on anatomy and function?ACTA OPHTHALMOLOGICA, Issue 2009C CREUZOT Purpose To present the structural and functional consequences on retina after retinal detachment Methods Author will show the consequences of experimental retinal detachment in animal models. These changes prevent retinal cells from a normal post-operative functioning. However, these conditions have to be differentiated from post-operative visual loss due to macular edema, long-standing subretinal fluid, epiretinal membrane or macular hole formation. Results Retinal detachment leads to severe changes on retinal cells: outer segment shortening, fibrosis, glial proliferation. This situation is the target of neuroprotective treatment. By contrast, some situations where the bad recevoery is due to an associated disease (edema, membrane...) illustrated by clinical cases can need surgical treatment. Conclusion Bad functional recovery after retinal detachment can be explained by anatomic consequences on photoreceptors with subclinical fibrosis or some associated complications. [source] Glaucoma associated with KProsACTA OPHTHALMOLOGICA, Issue 2009K HILLE Purpose Glaucoma is one of the most serious problems in Keratoprostheses. Already glaucoma is very frequent in patients with severe changes of the ocular surface requiring keratoprosthesis surgery. About 50% of those patients have pre-existing secondary glaucoma. Preoperatively all efforts should be done to detect its presence very early on. In KPro detection of glaucoma with traditional aids is difficult. A rough estimation of the tension by digital palpation will be the only available method. All indirect clues such as the medical history of glaucoma, echographic signs of disc cupping and anterior synechiae and examination of the visual field should be considered. Methods The incidence of postoperative secondary glaucoma vary among the different kinds of prostheses according to the surgery affecting the anterior segment and the long term anatomic results. In Osteo-Odonto-Keratoprostheses (OOKP) the most vision threatening complication is a primary or secondary glaucoma, due to the extended interventions required in the anterior segment. In Boston Keratoprostheses the risk seems to be somehow less. Results As the absorption of topical anti-glaucomatous medication will not reach the inner eye because of the anatomic barrier in KPro the only promising possibilities of treatment are systemic carbonic anhydrase inhibitors, different kinds of aqueous shunts and endo-cyclo-laserphotocoagulation. Conclusion Glaucoma is still a mayor problem in KPro. PS: This lession will be presented at the KPro-Meeting!! [source] Color, arousal, and performance,A comparison of three experimentsCOLOR RESEARCH & APPLICATION, Issue 2 2009Rikard Küller Abstract Three studies of the psychological and physiological effects on people of colored room interiors are described. Experiment 1 compared a colorful and a gray room, whereas in experiments 2 and 3 red and blue rooms were compared. The results indicate that the color of an interior space will have effects on many different levels. The perception of the room itself was affected, and the colors also had an impact on the emotions and physiology of those who stayed in the rooms. Strong, especially red, colors and patterns put the brain into a more excited state, sometimes to such an extent as to cause a paradoxical slowing of the heart rate. Introvert persons, as well as those already in a negative mood, became more affected than others, which caused severe changes in their performance. The series of experiments described here were among the first to be carried out in full-scale rooms painted or otherwise decorated in various colors. One practical implication is that a moderate use of good color design will serve to improve the overall mood and well-being of people. In future research more emphasis should be placed on color, as just one component in the highly complex real-life situations. © 2009 Wiley Periodicals, Inc. Col Res Appl, 34, 141,152, 2009 [source] | ||||||||||||||||