Analytical solution for tidal propagation in a coupled semi-confined/phreatic coastal aquifer

An analytical solution is derived for tidal fluctuations in a coupled coastal aquifer system consisting of a semi-confined aquifer, a thin semi-permeable layer and a phreatic aquifer. Based on the solution, we study the interactions (via leakage) between the confined and unconfined aquifers in response to tides. The results show that, under certain conditions, leakage from the confined aquifer can affect considerably the tidal water table fluctuation in the phreatic aquifer and vice versa. Ignoring these effects could lead to errors in estimating aquifer properties based on tidal signals. (C) 2002 Elsevier Science Ltd. All rights reserved.

An economic evaluation of plasma production via erythroplasmapheresis and whole blood collection

This paper presents cost-effectiveness analyses (CEAs) of plasma collection via two alternative methods: whole blood collection (WBC) and erythroplasmapheresis collection (EPC). The objective of the study is to provide an answer to the question 'What is the least-cost method of plasma production'. This question is answered, both from the viewpoint of the blood collection agency (using financial CEA) and from that of 'society' as a whole (using economic CEA). We employ detailed financial data and economic survey data for collections made by a blood collection agency and to WBC and EPC donors in Brisbane, Australia. The results indicate that, despite the superior yield provided by EPC, WBC is actually more cost-effective. This result is robust to thorough sensitivity analysis and arises regardless of whether an economic or financial perspective is taken. We conclude that, ceteris paribus, the cost of recruiting new plasma donors would need to be quite substantial for marginal investments in EPC to be considered cost-effective. Crown Copyright (C) 2002 Published by Elsevier Science Ltd. All rights reserved.

The Fornax Cluster Spectroscopic Survey: a sample of confirmed cluster dwarfs

The Fornax Cluster Spectroscopic Survey (FCSS) project utilizes the Two-degree Field (2dF) multi-object spectrograph on the Anglo-Australian Telescope (AAT). Its aim is to obtain spectra for a complete sample of all 14 000 objects with 16 5 less than or equal to b(j) less than or equal to 19 7 irrespective of their morphology in a 12 deg(2) area centred on the Fornax cluster. A sample of 24 Fornax cluster members has been identified from the first 2dF field (3.1 deg(2) in area) to be completed. This is the first complete sample of cluster objects of known distance with well-defined selection limits. Nineteen of the galaxies (with -15.8 < M-B < 12.7) appear to be conventional dwarf elliptical (dE) or dwarf S0 (dS0) galaxies. The other five objects (with -13.6 < M-B < 11.3) are those galaxies which were described recently by Drinkwater et al. and labelled 'ultracompact dwarfs' (UCDs). A major result is that the conventional dwarfs all have scale sizes alpha greater than or similar to 3 arcsec (similar or equal to300 pc). This apparent minimum scale size implies an equivalent minimum luminosity for a dwarf of a given surface brightness. This produces a limit on their distribution in the magnitude-surface brightness plane, such that we do not observe dEs with high surface brightnesses but faint absolute magnitudes. Above this observed minimum scale size of 3 arcsec, the dEs and dS0s fill the whole area of the magnitude-surface brightness plane sampled by our selection limits. The observed correlation between magnitude and surface brightness noted by several recent studies of brighter galaxies is not seen with our fainter cluster sample. A comparison of our results with the Fornax Cluster Catalog (FCC) of Ferguson illustrates that attempts to determine cluster membership solely on the basis of observed morphology can produce significant errors. The FCC identified 17 of the 24 FCSS sample (i.e. 71 per cent) as being 'cluster' members, in particular missing all five of the UCDs. The FCC also suffers from significant contamination: within the FCSS's field and selection limits, 23 per cent of those objects described as cluster members by the FCC are shown by the FCSS to be background objects.

Progressive dysgraphia in a case of posterior cortical atrophy

Dysgraphia (agraphia) is a common feature of posterior cortical atrophy (PCA). However, detailed analyses of these spelling and writing impairments are infrequently conducted. LM is a 59-year-old woman with dysgraphia associated with PCA. She presented with a two-year history of decline in her writing and dressmaking skills. A 3D T-1-weighted MRI scan confirmed selective bi-parietal atrophy, with relative sparing of the hippocampi and other cortical regions. Analyses of LM's preserved and impaired spelling abilities indicated mild physical letter distortions and a significant spelling deficit characterised by letter substitutions, insertions, omissions, and transpositions that was systematically sensitive to word length while insensitive to real word versus nonword category, word frequency, regularity, imagery, grammatical class and ambiguity. Our findings suggest a primary graphemic buffer disorder underlies LM's spelling errors, possibly originating from disruption to the operation of a fronto-parietal network implicated in verbal working memory.

Quantum control and quantum entanglement

We discuss quantum error correction for errors that occur at random times as described by, a conditional Poisson process. We shoo, how a class of such errors, detected spontaneous emission, can be corrected by continuous closed loop, feedback.

Organisational Factors Contributing to Violations by Rural and Remote Area Nurses during Medication Administration

Medication errors are a leading cause of unintended harm to patients in Australia and internationally. Research in this area has paid relatively little attention to the interactions between organisational factors and violations of procedures in producing errors, although violations have been found to increase the likelihood of these errors. This study investigated the role of organisational factors in contributing to violations by nurses when administering medications. Data were collected using a self-report questionnaire completed by 506 nurses working in either rural or remote areas in Queensland, Australia. This instrument was used to develop a path model wherein organisational variables predicted 21% of the variance in self-reported violations. Expectations of medical officers mediated the relationship between working conditions of nursing staff and violation behaviour.

Impact of the Subprime Crisis in the Provision of Credit Risk of Major National Banks

Financial institutions are directly exposed to the credit risk, that is, the risk of the borrower not fulfill with their obligations, paying their debts in its stated periods established previously. The bank predict this type of risk, including them in their balance-sheets. In 2006/2007 there was the impact of a new financial crisis that spread around the world, known as the crisis of subprime. The objective of this study is to analyze if the provisions for credit risk or liquidation increased the sprouting of the crisis of subprime in ten major national banks, chosen accordant to their total assets. To answer this question, the balance-sheets of each one of these banks in the period of 2005 to 2007 were analyzed. This research is characterized, as for its objectives, as descriptive and as for the procedures as documentary research. It is also characterized as having a qualitative approach. The results show that the crisis of subprime has caused little impact in the credit risk provision of the analyzed institutions. It was noticed a slight increase in the provision indicators at the peak of the crisis in 2006. These percentages were reduced in, 2007, probably reflecting the economic stability of Brazil and the stagnation of the crisis Of subprime in that year, at least in relation to in our country.

Patterns of brain asymmetry in the perception of positive and negative facial expressions

The divided visual field technique was used to investigate the pattern of brain asymmetry in the perception of positive/approach and negative/withdrawal facial expressions. A total of 80 undergraduate students (65 female, 15 male) were distributed in five experimental groups in order to investigate separately the perception of expressions of happiness, surprise, fear, sadness, and the neutral face. In each trial a target and a distractor expression were presented simultaneously in a computer screen for 150 ms and participants had to determine the side (left or right) on which the target expression was presented. Results indicated that expressions of happiness and fear were identified faster when presented in the left visual field, suggesting an advantage of the right hemisphere in the perception of these expressions. Fewer judgement errors and faster reaction times were also observed for the matching condition in which emotional faces were presented in the left visual field and neutral faces in the right visual field. Other results indicated that positive expressions (happiness and surprise) were perceived faster and more accurately than negative ones (sadness and fear). Main results tend to support the right hemisphere hypothesis, which predicts a better performance of the right hemisphere to perceive emotions, as opposed to the approach-withdrawal hypothesis.

Two-dimensional approximation for tidal dynamics in coastal aquifers: Capillarity correction

Most previous investigations on tide-induced watertable fluctuations in coastal aquifers have been based on one-dimensional models that describe the processes in the cross-shore direction alone, assuming negligible along-shore variability. A recent study proposed a two-dimensional approximation for tide-induced watertable fluctuations that took into account coastline variations. Here, we further develop this approximation in two ways, by extending the approximation to second order and by taking into account capillary effects. Our results demonstrate that both effects can markedly influence watertable fluctuations. In particular, with the first-order approximation, the local damping rate of the tidal signal could be subject to sizable errors.

Homicide mortality, socioeconomic development, and police violence in the city of Sao Paulo, Brazil

Objective. To analyze the association between police violence and homicide mortality rates taking into consideration the effect of contextual variables. Methods. This was an environmental, cross-sectional study that included the 96 census districts in the City of Sao Paulo. The association between the variables was analyzed using Spearman`s rank correlation and simple and multiple regression analysis. Results. Univariate analysis revealed a strong and significant association between homicide mortality coefficients and all the indicators of socioeconomic development and police violence. After controlling for potential confounding factors, the association between police violence and homicide mortality coefficients remained strong and significant. This significance was lost only after control for the size of the resident population. Conclusion. The results indicate that police action that violates basic human rights is not the right answer to urban violence. The combination of homicides from interpersonal violence and deaths from police violence results in negative socialization and promotes further violence.

NEWS CONCERNING A CERTAIN TAMOIO CONFEDERATION

In this article we revisit a famous chapter of Brazilian history, yet to be properly analysed from an ethnological perspective: the `Tamoio confederation,` a coalition of 16th century coastal Tupian groups who threatened to undermine Portuguese colonization during the dispute between the French and Portuguese for the Guanabara region (now Rio de Janeiro). Was this `confederation` a new phenomenon in Tupian politics, engendered by the Conquest and inducing a shift towards political centralization? Or was it, on the contrary, the actualization of a possibility already (always) present in Tupian forms of political organization and action? These are the questions guiding our inquiry, which we seek to answer through the use of both historical sources and the in-depth ethnological knowledge of Tupi-Guarani peoples developed by various authors over recent decades.

Usefulness of liver biopsy in chronic hepatitis C

Major requirements for performance of liver biopsy (LB) are the benefits for the patient and the impossibility of having the same information by less invasive procedures. In the last two decades physicians have faced the difficult task of convincing a patient positive for hepatitis C, with minimal clinical or laboratory alterations to be submitted to LB in order to evaluate the status of the disease for therapeutic management. The characteristics of the needle used for percutaneous LB interferes with the accuracy of diagnosis. In chronic hepatitis C (CHC), validity is achieved with liver fragments about 25mm in length containing more than 10 portal tracts. Morbidity due to LB is mainly related to bleeding but death is very rare. Severe complications are also uncommon, increasing with number of passes and decreasing with experience of operator and ultrasound guidance. Although CHC is a diffuse disease, the various areas of the liver may not be equally affected and sampling errors are possible. Another potential limitation of LB is the discordance between pathologists in its interpretation. To replace LB, many panels of surrogate markers have been described, aiming to identify extent of fibrosis and inflammation. All of them have used LB as their ""gold standard"". Liver biopsy continues to be the most reliable method to evaluate the possibility of therapy for CHC. Universal treatment of all patients with diagnosis of CHC would be ideal. But, there are mainly three drawbacks. Overall efficacy is as low as 50%, side effects are common and may be severe and treatment is prolonged and expensive. The acceptability of the biopsy by the patient is highly dependent on the physician`s conviction of its usefulness.

Oculometric parameters of hyperopia in children with esotropic amblyopia

Purpose: To study the oculometric parameters of hyperopia in children with esotropic amblyopia, comparing amblyopic eyes with fellow eyes. Methods: Thirty-seven patients (5-8 years old) with bilateral hyperopia and esotropic amblyopia underwent a comprehensive ophthalmic examination, including cycloplegic refraction, keratometry and A-scan ultrasonography. Anterior chamber depth, lens thickness, vitreous chamber depth and total axial length were recorded. The refractive power of the crystalline lens was calculated using Bennett`s equations. Paired Student`s t-tests were used to compare ocular biometric measurements between amblyopic eyes and their fellow eyes. The associations of biometric parameters with refractive errors were assessed using Pearson correlation coefficients and linear regression. Multivariable models including axial length, corneal power and lens power were also constructed. Results: Amblyopic eyes were found to have significantly more hyperopic refraction, less corneal power, greater lens power, shorter vitreous chamber depth and shorter axial length, despite similar anterior chamber depth and lens thickness. The strongest correlation with refractive error was observed for the axial length/corneal radius ratio (r(36) = -0.92, p < 0.001 for amblyopic and r(36) = 0.87, p < 0.001 for fellow eyes). Axial length accounted for 39.2% (R(2)) of the refractive error variance in amblyopic eyes and 35.5% in fellow eyes. Adding corneal power to the model increased R(2) to 85.7% and 79.6%, respectively. A statistically significant correlation was found between axial length and corneal power, indicating decreasing corneal power with increasing axial length, and they were similar for amblyopic eyes (r(36) = 0.53,p < 0.001) and fellow eyes (r(36) = -0.57, p < 0.001). A statistically significant correlation was also found between axial length and lens power, indicating decreasing lens power with increasing axial length (r(36) = -0.72, p < 0.001 for amblyopic eyes and r(36) = -0.69, p < 0.001 for fellow eyes). Conclusions: We observed that the correlation among the major oculometric parameters and their individual contribution to hyperopia in esotropic children were similar in amblyopic and non-amblyopic eyes. This finding suggests that the counterbalancing effect of greater corneal and lens power associated with shorter axial length is similar in both eyes of patients with esotropic amblyopia.

Acute Toxic Leukoencephalopathy: Potential for Reversibility Clinically and on MRI With Diffusion-Weighted and FLAIR Imaging

OBJECTIVE. Toxic leukoencephalopathy may present acutely or subacutely with symmetrically reduced diffusion in the periventricular and supraventricular white matter, hereafter referred to as periventricular white matter. This entity may reverse both on imaging and clinically. However, a gathering together of the heterogeneous causes of this disorder as seen on MRI with diffusion-weighted imaging (DWI) and an analysis of their likelihood to reverse has not yet been performed. Our goals were to gather causes of acute or subacute toxic leukoencephalopathy that can present with reduced diffusion of periventricular white matter in order to promote recognition of this entity, to evaluate whether DWI with apparent diffusion coefficient (ADC) values can predict the extent of chronic FLAIR abnormality ( imaging reversibility), and to evaluate whether DWI can predict the clinical outcome ( clinical reversibility). MATERIALS AND METHODS. Two neuroradiologists retrospectively reviewed the MRI examinations of 39 patients with acute symptoms and reduced diffusion of periventricular white matter. The reviewers then scored the extent of abnormality on DWI and FLAIR. ADC ratios of affected white matter versus the unaffected periventricular white matter were obtained. Each patient`s clinical records were reviewed to determine the cause and clinical outcome. Histology findings were available in three patients. Correlations were calculated between the initial MRI markers and both the clinical course and the follow-up extent on FLAIR using Spearman`s correlation coefficient. RESULTS. Of the initial 39 patients, seven were excluded because of a nontoxic cause (hypoxic-ischemic encephalopathy [HIE] or congenital genetic disorders) or because of technical errors. In the remaining 32 patients, no correlation was noted between any of the initial MRI markers (percentage of ADC reduction, DWI extent, or FLAIR extent) with the clinical outcome. Three patients had histologic correlation. However, moderate correlation was seen between the extent of abnormality on initial FLAIR and the extent on follow-up FLAIR (r = 0.441, p = 0.047). Of the 13 patients who underwent repeat MRI at 21 days or longer, the reduced diffusion resolved in all but one. Significant differences were noted between ADC values in affected white matter versus unaffected periventricular white matter on initial (p < 0.0001) but not on follow-up MRI (p = 0.13), and in affected white matter on initial versus follow-up (p = 0.0014) in those individuals who underwent repeat imaging on the same magnet (n = 9), confirming resolution of the DWI abnormalities. CONCLUSION. Acute toxic leukoencephalopathy with reduced diffusion may be clinically reversible and radiologically reversible on DWI, and may also be reversible, but to a lesser degree, on FLAIR MRI. None of the imaging markers measured in this study appears to correlate with clinical outcome, which underscores the necessity for prompt recognition of this entity. Alerting the clinician to this potentially reversible syndrome can facilitate treatment and removal of the offending agent in the early stages.

Quality of life and neuropsychological changes in mild head trauma - Late analysis and correlation with S100B protein and cranial CT scan performed at hospital admission

Introduction: mild head trauma (MHT) is defined as a transient neurological deficit after trauma with a history of impairment or loss of consciousness lasting less than 15 min and/or posttraumatic amnesia, and a Glasgow Coma Scale between 13 and 15 on hospital admission. We evaluated 50 MHT patients 18 months after the trauma, addressing signs and symptoms of post-concussion syndrome, quality of life and the presence of anxiety and depression. We correlate those findings with the S100B protein levels and cranial CT scan performed at hospital admission after the trauma. Method: patients were asked to fill out questionnaires to assess quality of life (SF36), anxiety and depression (HADS), and signs and symptoms of post-concussion syndrome. For the control group, we asked the patient`s household members, who had no history of head trauma of any type, to answer the same questionnaires for comparison. Results: total quality of life index for patients with MHT was 58.16 (+/-5), lower than the 73.47 (+/-4) presented by the control group. Twenty patients (55.2%) and four (11.1%) controls were depressed. Seventeen patients (47.2%) presented anxiety, whereas only eight (22.2%) controls were considered anxious. Victims of MHT complained more frequently of loss of balance, dry mouth, pain in the arms, loss of memory and dizziness than their respective controls (p < 0.05). We found no correlation between the presence of these signs and symptoms, quality of life, presence of anxiety and depression with S100B protein levels or with presence of injury in the cranial CT performed at hospital admission. Conclusion: MHT is associated with a higher incidence of post-concussion syndrome symptoms, lower quality of life and anxiety than their respective controls even 18 months after the trauma. (C) 2007 Elsevier Ltd. All rights reserved.