Causes and Mechanisms

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Head Injury Depth as an Indicator of Causes and Mechanisms

Head Injury Depth as an Indicator of Causes and Mechanisms

CONCLUSIONS For infants and young children hospi- talized for evaluation and treatment of acute, nonpenetrating, head trauma, assessment of head injury depth facil- itates the assessment of head injury causes and mechanisms. Acute en- cephalopathy, acute respiratory or circulatory compromise, and inter- hemispheric or bilateral subdural hemorrhage seem to be markers of subcortical brain injury. Infants and young children who demonstrate visi- ble subcortical injuries unrelated to a MVC require thorough evaluation for abuse. These results have diagnostic, prognostic, and forensic significance.
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Causes  and mechanisms of intrauterine hypoxia and its impact on the fetal cardiovascular system: a review

Causes and mechanisms of intrauterine hypoxia and its impact on the fetal cardiovascular system: a review

Correspondence should be addressed to Damian Hutter, damian.hutter@insel.ch Received 18 March 2010; Revised 4 August 2010; Accepted 16 September 2010 Academic Editor: Anita J. Moon-Grady Copyright © 2010 Damian Hutter et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Until today the role of oxygen in the development of the fetus remains controversially discussed. It is still believed that lack of oxygen in utero might be responsible for some of the known congenital cardiovascular malformations. Over the last two decades detailed research has given us new insights and a better understanding of embryogenesis and fetal growth. But most importantly it has repeatedly demonstrated that oxygen only plays a minor role in the early intrauterine development. After organogenesis has taken place hypoxia becomes more important during the second and third trimester of pregnancy when fetal growth occurs. This review will briefly adress causes and mechanisms leading to intrauterine hypoxia and their impact on the fetal cardiovascular system.
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Identifying the causes of differences in ozone production from the CB05 and CBMIV chemical mechanisms

Identifying the causes of differences in ozone production from the CB05 and CBMIV chemical mechanisms

Abstract. An investigation was conducted to identify the mechanistic differences between two versions of the carbon bond gas-phase chemical mechanism (CB05 and CBMIV) which consistently lead to larger ground-level ozone concen- trations being produced in the CB05 version of the National Air Quality Forecasting Capability (NAQFC) modeling sys- tem even though the two parallel forecast systems utilize the same meteorology and base emissions and similar initial and boundary conditions. Box models of each of the mechanisms as they are implemented in the NAQFC were created and a set of 12 sensitivity simulations was designed. The sensitiv- ity simulations independently probed the conceptual mecha- nistic differences between CB05 and CBMIV and were ex- ercised over a 45-scenario simulation suite designed to em- ulate the wide range of chemical regimes encountered in a continental-scale atmospheric chemistry model. Results of the sensitivity simulations indicate that two sets of reactions that were included in the CB05 mechanism, but which were absent from the CBMIV mechanism, are the primary causes of the greater ozone production in the CB05 version of the NAQFC. One set of reactions recycles the higher organic peroxide species of CB05 (ROOH), resulting in additional photochemically reactive products that act to produce addi- tional ozone in some chemical regimes. The other set of re- actions recycles reactive nitrogen from less reactive forms back to NO 2 , increasing the effective NO x concentration of
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Causes of desertion in the English teaching and translation bachelors degree programs and prevention mechanisms

Causes of desertion in the English teaching and translation bachelors degree programs and prevention mechanisms

Causes of desertion in the English teaching and translation bachelors degree programs and prevention mechanisms 2002-1-2005-2 Martha E. Guzmán O. - Responsible for the Coordination of Educative and Psychological Guidance of the Language School in Mexicali (2003 -.) Students support activities such as attention to aspiring students of new enrollment, Newcomers course, vocational and psychological orientation for university students, vocational and psychological orientation for teachers. Responsible for the Coordination of Educative and Psychological Guidance of the Architecture Faculty (2000-2003). Psychologist in Centros de Integración Juvenil, A.C. (C.R. Tijuana (1996-2000)
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Process Disturbances in Agricultural Biogas Production—Causes, Mechanisms and Effects on the Biogas Microbiome: A Review

Process Disturbances in Agricultural Biogas Production—Causes, Mechanisms and Effects on the Biogas Microbiome: A Review

* Correspondence: susanne.theuerl@googlemail.com; Tel.: +49-331-5699-900 Received: 20 December 2018; Accepted: 19 January 2019; Published: 24 January 2019 Abstract: Disturbances of the anaerobic digestion process reduce the economic and environmental performance of biogas systems. A better understanding of the highly complex process is of crucial importance in order to avoid disturbances. This review defines process disturbances as significant changes in the functionality within the microbial community leading to unacceptable and severe decreases in biogas production and requiring an active counteraction to be overcome. The main types of process disturbances in agricultural biogas production are classified as unfavorable process temperatures, fluctuations in the availability of macro- and micronutrients (feedstock variability), overload of the microbial degradation potential, process-related accumulation of inhibiting metabolites such as hydrogen (H 2 ), ammonium/ammonia (NH 4 + /NH 3 ) or hydrogen sulphide (H 2 S) and inhibition by other organic and inorganic toxicants. Causes, mechanisms and effects on the biogas microbiome are discussed. The need for a knowledge-based microbiome management to ensure a stable and efficient production of biogas with low susceptibility to disturbances is derived and an outlook on potential future process monitoring and control by means of microbial indicators is provided.
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How Cannabis Causes Paranoia: Using the Intravenous Administration of ∆^{9}-Tetrahydrocannabinol (THC) to Identify Key Cognitive Mechanisms Leading to Paranoia

How Cannabis Causes Paranoia: Using the Intravenous Administration of ∆^{9}-Tetrahydrocannabinol (THC) to Identify Key Cognitive Mechanisms Leading to Paranoia

The Current Study In the current study, we set out to identify the causes of paranoia via the administration of THC. This requires a between-groups test of the administration of THC against placebo. A third condition tested a further causal factor: misinterpretation. The cognitive perspective con- siders paranoia to be a misinterpretation of events. If individuals are made sufficiently aware of the potential subjective effects of THC, then this may alter the inter- pretation made and hence the occurrence of paranoia. Therefore, the third condition was a cognitive awareness manipulation in which the potential effects of THC were explained before drug administration. The participants to be tested were selected from the general population on the key criterion of having had recent paranoid ideation. This was therefore an analogue population, in order that the results are applicable to understanding the clinical phenomenon; testing individuals without signs of vulner- ability to disorder would be much less informative about clinical paranoia, while testing patients in such large numbers would have ethical and practical difficulties. We were mindful of “the paranoia problem,” the difficulty of determining whether persecutory ideation is unfounded, so the battery of tests included the most extensive range of paranoia assessments yet used in a study. There were 3 hypotheses: (a) THC increases the occurrence of para- noia, (b) the occurrence of anomalous experiences and negative affect (but not alterations in working memory) explains (ie, mediates) the increase in paranoia, and (c) that paranoid interpretations can be partially blocked by cognitive awareness. The second hypothesis concern- ing underling mechanisms is the hardest to establish—we note the advice of Bullock and colleagues 20 “to think of mediation analysis as a cumulative enterprise.”
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Genetic causes and mechanisms of distal renal tubular acidosis

Genetic causes and mechanisms of distal renal tubular acidosis

Mechanisms of dRTA in AE1 mutants The molecular mechanisms that render a mutated protein dysfunctional are complex and may involve an array of defects spanning from internal sequestration of a given transporter to its mistargeting to the plasma membrane. A scheme of AE1 mutations resulting in non-function, internal sequestration in endoplasmic reticulum or Golgi apparatus, or mistargeting to the apical membrane is shown in Figure 2. Next are reviewed studies that have shown various mutations in patients with dRTA and cell biology studies aimed at exploring the potential mechan- ism that result in impaired function of the various acid – base transporters involved.
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Causes and mechanisms of the 2011-2012 El Hierro (Canary Islands) submarine eruption

Causes and mechanisms of the 2011-2012 El Hierro (Canary Islands) submarine eruption

2011 to 5 March 2012 (eruptive episode).. Diagram comparing the variation of the main geophysical parameters with time. B) Depth of seismic events. C) Surface deformation[r]

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Causes and mechanisms of synchronous succession trajectories in primeval Central European mixed Fagus sylvatica forests

Causes and mechanisms of synchronous succession trajectories in primeval Central European mixed Fagus sylvatica forests

FIGURE 9 Percentages of selected pollen types, palynological richness (PRI), microscopic charcoal influx, macroscopic charcoal presence (≥600. 902[r]

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Causes and mechanisms of an adverse outcome in patients with glucose abnormalities and cardiovascular disease : epidemiological and biochemical analyses

Causes and mechanisms of an adverse outcome in patients with glucose abnormalities and cardiovascular disease : epidemiological and biochemical analyses

underlying causes of mortality after myocardial infarction does not seem to differ between patients with or without diabetes mellitus although they occur at an earlier time point in the latter group. This illustrates the importance of preventing both development of diabetes, thereby reducing duration of overt diabetes and its adverse outcome including cardiovascular complications following an established event. Until recently focus has been on the impact of glucose lowering therapies. This approach had limited effects on cardiovascular mortality and morbidity unless the glycaemic control was very poorly controlled as in the DIGAMI study. In the future other preventive approaches than glucose control should be more prioritised. An attractive strategy could for instance be a multifactorial treatment targeting several components of the metabolic syndrome including an elevated state of inflammation. The ALECARDIO study was one such broad approach but was terminated due to lack of futility and drug related problems. 259 Other novel therapies of interest are for instance PCSK9-
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Causes of Failure and Alternative Mechanisms of Lamps

Causes of Failure and Alternative Mechanisms of Lamps

By comparing the lamps produced by four different manufacturers at room temperature and high temperature, we found that (1) long-term placement can change the chromaticity (color) o[r]

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Fragile X syndrome: causes, diagnosis, mechanisms, and therapeutics

Fragile X syndrome: causes, diagnosis, mechanisms, and therapeutics

inhibition balance appear to be the effects of the disease, fur- ther studies are necessary to fully address this question. In addition, FMRP is also required for neural stem and progeni- tor cell proliferation, differentiation, and survival, suggesting additional mechanisms that could explain certain features of the disease (136). Intensive educational interventions in FXS, in addition to these targeted treatments, are important to both strengthen synaptic connections and improve the quality of life for patients. The continued development of new, targeted treat- ments for FXS, together with existing induced pluripotent stem cell models for FXS (63), give hope that reversing the behavioral and cognitive deficits seen in individuals with this disorder may someday be possible.
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Elements of novelty, known mechanisms, and the fundamental causes of the recent crisis

Elements of novelty, known mechanisms, and the fundamental causes of the recent crisis

For instance, Stiglitz (2002) maintained that the gradualism in the transition to a market- oriented environment has been a winning strategy for some countries while one of the major causes of the Asian crisis has been a too fast deregulation in other countries. All in all, the so-called global imbalances emerged as a consequence of the penetration of China and other emerging economies in global markets: capitalist accumulation has expanded towards the East following the profitability deriving from low costs of production, 14 benefiting from capital flows leaking out from the West (FDI, MNEs, etc.), according to a process initiated by the same political decisions which have gradually deregulated and financialised advanced economies and the international system.
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Cellular mechanisms of Cnidarian bleaching: stress causes the collapse of symbiosis

Cellular mechanisms of Cnidarian bleaching: stress causes the collapse of symbiosis

Cnidarian bleaching is a breakdown in the mutualistic symbiosis between host Cnidarians, such as reef building corals, and their unicellular photosynthetic dinoflagellate symbionts. Bleaching is caused by a variety of environmental stressors, most notably elevated temperatures associated with global climate change in conjunction with high solar radiation, and it is a major contributor to coral death and reef degradation. This review examines the underlying cellular events that lead to symbiosis dysfunction and cause bleaching, emphasizing that, to date, we have only some pieces of a complex cellular jigsaw puzzle. Reactive oxygen species (ROS), generated by damage to both photosynthetic and mitochondrial membranes, is shown to play a central role in both injury to the partners and to inter-partner communication of a stress response. Evidence is presented that suggests that bleaching is a host innate immune response to a compromised symbiont, much like innate immune responses in other host–microbe interactions. Finally, the elimination or exit of the symbiont from host tissues is described through a variety of mechanisms including exocytosis, host cell detachment and host cell apoptosis.
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Fundamentals of Corrosion Mechanisms, Causes, and Preventative Methods 2009.pdf

Fundamentals of Corrosion Mechanisms, Causes, and Preventative Methods 2009.pdf

Corrosion Mechanisms 9 2.2.1 Dissimilar Electrode Cells Dissimilar electrode cells may be formed when two dissimilar metals are in contact or due to the heterogeneity of the same metal surface. The Daniel cell is an example of the former. In practice, a copper pipe con- nected to a steel pipe or a bronze propeller in contact with the steel hull of a ship provides an example of this type of corrosion cell. This is often referred to as galvanic coupling, in which the less noble metal becomes the anode. Galvanic corrosion is discussed further in Chapter 3. A cold worked metal in contact with the same metal annealed leads to a similar situation (i.e., the cold worked metal remaining anodic). On the same metal surface, such type of cell formation may result from dissimilar phases and impurities, grain boundaries, differentially strained areas, and scratches or abrasions. In a single crystal, the different crystal faces differ in their electrochemical characteristics because of the difference in their atomic orientation and, as a result, one crystal face tends to become anodic com- pared to the others.
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Causes without Mechanisms: Experimental Regularities, Physical Laws, and Neuroscientific Explanation

Causes without Mechanisms: Experimental Regularities, Physical Laws, and Neuroscientific Explanation

As such, they can point investigators to facts that need to be explained and to the workings of the underlying mechanisms. It is these mechanisms that are doing the explanatory work; the regularities are merely tools for their discovery. I absolutely agree with Bogen that regularities such as the ones contained in the HH equations play important epistemic roles other than explanation. However, as I will show here, the fact that the HH model summarized, in a systematic way, a large number of experiments does not exclude that it also had explanatory force.

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Genetic causes and molecular mechanisms underlying rare metabolic bone diseases

Genetic causes and molecular mechanisms underlying rare metabolic bone diseases

ABSTRACT The skeletal system provides support for the body, enables movement and protects inner organs. Moreover, it supplies blood cells and acts as a reservoir for minerals and fat. Several external factors, including nutrition and long-term illness, influence bone health but genetic factors also play an important role. More than 400 different rare skeletal diseases, collectively called skeletal dysplasias, have thus far been delineated and mutations in over 350 genes have been identified as underlying causes in these conditions. Although the recent evolution of the sequencing technologies and molecular methods has increased diagnostic yield of rare skeletal diseases, knowledge on the genetic and phenotypic features in some of these conditions is still limited and novel forms of skeletal dysplasia still remain to be characterized.
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Autism spectrum disorder causes, mechanisms, and treatments: Focus on neuronal synapses

Autism spectrum disorder causes, mechanisms, and treatments: Focus on neuronal synapses

A related well-known example is the selective effect of risperi- done. Risperidone, a dopamine antagonist, is an antipsychotic mainly used to treat schizophrenia and bipolar disorder, and it is currently one of the few FDA-approved medications for autism. The drug mainly ameliorates irritability, hyperactivity, and repetitive and restricted behaviors, but is largely ineffective against social withdrawal and language deficits of autistic indi- viduals (McPheeters et al., 2011). Similarly, risperidone rescues repetitive grooming and hyperactivity, but not social deficits, in Cntnap2 −/− mice (Penagarikano et al., 2011). Another example is the demonstration that CDPPB rescues only social interaction in Shank2-deficient mice but fails to rescue impaired pup retrieval, repetitive jumping, hyperactivity, and anxiety-like behavior (Won et al., 2012). The fact that some medications reverse only selec- tive symptoms/phenotypes of ASD, however, may provide an opportunity to further explore detailed mechanisms underly- ing particular aspects of ASD etiology. This would, in principle, allow us to dissect and study synaptic or circuit mechanisms that are specifically associated with certain aspects of ASD, such as impaired social interaction, impaired social communication, repetitive behavior, restricted interests, intellectual disability, anx- iety, and hyperactivity.
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Apparent dryland salinity on the uplands of southeastern Australia; quantification of biotic and abiotic indicators, causes, mechanisms, processes and effects

Apparent dryland salinity on the uplands of southeastern Australia; quantification of biotic and abiotic indicators, causes, mechanisms, processes and effects

Log taxa. As no association was found between Scald and the second EM31 survey season (S2) following rainfall, any groundwater recharge that occurred following this rainfall did not have any effect on deeper conductivity. Therefore, no evidence for groundwater influence on scald formation or ongoing condition was found. It follows that the surface degradation causes the bare area, increasing the surface evaporation potential and in some cases forming a bare area with increased evaporite deposition, hence elevated salinity levels. No evidence was found for the process to be vice versa, that is, for the salt to ‘rise’ from beneath, thereby killing the vegetation and degrading the soil, leaving a bare scalded area. Considering this and the observations mentioned in Chapter 9 such as small scalds within patches of healthy vegetation, and larger scalds surrounded by healthy vegetation, evidence suggests that scalding occurs from surficial factors. The soil evaporation potential is increased, in other words, a top down process, not bottom up as the rising groundwater model stipulates. This is also confirmed from the biotic variables being more strongly correlated with Scald than EC as discussed in Chapters 8 and 9.
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The causes of epistasis

The causes of epistasis

Experimentally Evolved Adaptive Mutations Causes a Rugged Fitness Landscape. 2011 Molecular mechanisms of epistasis within and between genes[r]

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