Calculation of wood volume and stem taper using terrestrial single-image close-range photogrammetry and contemporary software tools

Abstract

Investigation of Two Bridge Alternatives for Low Volume Roads - Phase II Volume 2 of 2, Concept 2: Beam in Slab Bridge, TR-410, 2000

This project continues the research which addresses the numerous bridge problems on the Iowa secondary road system. It is a continuation (Phase 2) of Project HR-382, in which two replacement alternatives (Concept 1: Steel Beam Precast Units and Concept 2: Modification of the Benton County Beam-in-Slab Bridge) were investigated. In previous research for concept 1, a precast unit bridge was developed through laboratory testing. The steel-beam precast unit bridge requires the fabrication of precast double-tee (PCDT) units, each consisting of two steel beams connected by a reinforced concrete deck. The weight of each PCDT unit is minimized by limiting the deck thickness to 4 in., which permits the units to be constructed off-site and then transported to the bridge site. The number of units required is a function of the width of bridge desired. Once the PCDT units are connected, a cast-in-place reinforced concrete deck is cast over the PCDT units and the bridge railing attached. Since the steel beam PCDT unit bridge design is intended primarily for use on low-volume roads, used steel beams can be utilized for a significant cost savings. In previous research for concept 2, an alternate shear connector (ASC) was developed and subjected to static loading. In this investigation, the ASC was subjected to cyclic loading in both pushout specimens and composite beam tests. Based on these tests, the fatigue strength of the ASC was determined to be significantly greater than that required in typical low volume road single span bridges. Based upon the construction and service load testing, the steel-beam precast unit bridge was successfully shown to be a viable low volume road bridge alternative. The construction process utilized standard methods resulting in a simple system that can be completed with a limited staff. Results from the service load tests indicated adequate strength for all legal loads. An inspection of the bridge one year after its construction revealed no change in the bridge's performance. Each of the systems previously described are relatively easy to construct. Use of the ASC rather than the welded studs significantly simplified the work, equipment, and materials required to develop composite action between the steel beams and the concrete deck.

Superpave Mix Designs for Low Volume Roads, Construction Report, TR-414, 2001

Most research current to the time of these projects was focused on use of Superpave mix designs on higher volume roads. Low volume roads have different requirements in terms of mix design, aggregate types, aggregate sources and project budgets. The purpose of this research was to determine if the Superpave mix design strategy for low volume roads was practical and economical. Eight projects were selected in five counties. The projects were completed in the summer of 1998. Performance evaluation of the resulting pavements was carried out annually. There was no significant increase in costs related to the use of Superpave. Nor were there any significant construction issues. There were some differences noted in placement and compaction in the field, but these were not serious.

Hippocampal and amygdalar volume changes in elderly patients with Alzheimer's disease and schizophrenia.

Patients with Alzheimer's disease (AD) and schizophrenia display cognitive, behavioural disturbances and morphological abnormalities. Although these latter reflect progressive neurodegeneration in AD, their significance in schizophrenia is still unclear. We explored the patterns of hippocampal and amygdalar atrophy in those patients and their associations with clinical parameters. Structural magnetic resonance imaging was performed in 20 elderly schizophrenia patients, 20 AD and 19 healthy older controls. Hippocampal and amygdalar volumes were obtained by manual segmentation with a standardized protocol and compared among groups. In both schizophrenia and AD patients, left hippocampal and amygdalar volumes were significantly smaller. The hippocampus/amygdala ratio was significantly lower in schizophrenia compared to both AD cases [2.4 bilaterally, 95% C.I. 2.2 to 2.7] and healthy controls bilaterally [2.5, 95% C.I. 2.3 to 2.9 in left and 2.7, 95% C.I. 2.4 to 3.1 in right hemisphere]. In schizophrenia patients, a significant positive correlation was found between age at disease onset and the right hippocampus/amygdala volume ratio (Spearman rho=0.56). Negative symptoms correlated with higher right/left amygdala volume ratio (Spearman's rho=0.43). Our data show that unlike AD, the hippocampus/amygdala ratio is abnormally low and correlates with the age at onset in schizophrenia, being a neurodevelopmental signature of the disease.

Comparison of microscopic method and computational program for pesticide deposition evaluation of spraying

The main objective of this work was to compare two methods to estimate the deposition of pesticide applied by aerial spraying. Hundred and fifty pieces of water sensitive paper were distributed over an area of 50 m length by 75 m width for sampling droplets sprayed by an aircraft calibrated to apply a spray volume of 32 L/ha. The samples were analysed by visual microscopic method using NG 2 Porton graticule and by an image analyser computer program. The results reached by visual microscopic method were the following: volume median diameter, 398±62 mum; number median diameter, 159±22 mum; droplet density, 22.5±7.0 droplets/cm² and estimated deposited volume, 22.2±9.4 L/ha. The respective ones reached with the computer program were: 402±58 mum, 161±32 mum, 21.9±7.5 droplets/cm² and 21.9±9.2 L/ha. Graphs of the spatial distribution of droplet density and deposited spray volume on the area were produced by the computer program.

An operator formulation of the multiscale finite-volume method with correction function

The multiscale finite-volume (MSFV) method has been derived to efficiently solve large problems with spatially varying coefficients. The fine-scale problem is subdivided into local problems that can be solved separately and are coupled by a global problem. This algorithm, in consequence, shares some characteristics with two-level domain decomposition (DD) methods. However, the MSFV algorithm is different in that it incorporates a flux reconstruction step, which delivers a fine-scale mass conservative flux field without the need for iterating. This is achieved by the use of two overlapping coarse grids. The recently introduced correction function allows for a consistent handling of source terms, which makes the MSFV method a flexible algorithm that is applicable to a wide spectrum of problems. It is demonstrated that the MSFV operator, used to compute an approximate pressure solution, can be equivalently constructed by writing the Schur complement with a tangential approximation of a single-cell overlapping grid and incorporation of appropriate coarse-scale mass-balance equations.

A prospective molecular surveillance study evaluating the clinical impact of community-acquired respiratory viruses in lung transplant recipients.

BACKGROUND: Community-acquired respiratory viral infections (RVIs) are common in lung transplant patients and may be associated with acute rejection and bronchiolitis obliterans syndrome (BOS). The use of sensitive molecular methods that can simultaneously detect a large panel of respiratory viruses may help better define their effects. METHODS: Lung transplant recipients undergoing serial surveillance and diagnostic bronchoalveolar lavages (BALs) during a period of 3 years were enrolled. BAL samples underwent multiplex testing for a panel of 19 respiratory viral types/subtypes using the Luminex xTAG respiratory virus panel assay. RESULTS: Demographics, symptoms, and forced expiratory volume in 1 sec were prospectively collected for 93 lung transplant recipients enrolled. Mean number of BAL samples was 6.2+/-3.1 per patient. A respiratory virus was isolated in 48 of 93 (51.6%) patients on at least one BAL sample. Of 81 positive samples, the viruses isolated included rhinovirus (n=46), parainfluenza 1 to 4 (n=17), coronavirus (n=11), influenza (n=4), metapneumovirus (n=4), and respiratory syncytial virus (n=2). Biopsy-proven acute rejection (> or =grade 2) or decline in forced expiratory volume in 1 sec > or =20% occurred in 16 of 48 (33.3%) patients within 3 months of RVI when compared with 3 of 45 (6.7%) RVI-negative patients within a comparable time frame (P=0.001). No significant difference was seen in incidence of acute rejection between symptomatic and asymptomatic patients. Biopsy-proven obliterative bronchiolitis or BOS was diagnosed in 10 of 16 (62.5%) patients within 1 year of infection. CONCLUSION: Community-acquired RVIs are frequently detected in BAL samples from lung transplant patients. In a significant percentage of patients, symptomatic or asymptomatic viral infection is a trigger for acute rejection and obliterative bronchiolitis/BOS.

The Iowa plan for atomic energy education, 1950

This is volume 1 of 5 and is the Iowa Plan for Atomic Energy Education. It is the orientation to the Iowa plan for atomic energy education. This plan was presented to teachers, students and the lay public of Iowa with the desire to remove fears and assist in pointing the way toward a sensitive consideration of what American citizens can and should know and do about atomic energy.

The reasons for discrepancies in target volume delineation: a SASRO study on head-and-neck and prostate cancer

But : comprendre les raisons des divergences observées dans le tracé des volumes cibles entre radio-oncologues. Matériel et méthodes : 18 centres suisses de radio-oncologie ont été invités à tracer les volumes pour un cas de cancer de la prostate et pour un cas de cancer de la sphère ORL. Nous avons également envoyé un questionnaire pour évaluer d'une part les différences dans la définition- des volumes (GTV [ gross tumor volume= volume tumoral macroscopique ], CTV [clinical tumor volume= volume de la tumeur clinique, macroscopique et microscopique], PTV [planning target volume= volume cible pour la planification], et d'autre part des variations dans les marges appliquées et les ganglions considérés à risque. Pour chaque centre, on a calculé la corrélation entre les marges qui ont été dessinées et celles qui ont été annoncées. Nous avons inclus dans le questionnaire une série de questions non spécifiques pour évaluer les méthodes de planification utilisées dans les différents centres. Résultats : Dans les 2 situations cliniques, on a mis en évidence de relativement grandes différences tant au niveau des volumes dessinés par les différents centres que dans leur définition des volumes. La corrélation entre les marges dessinées et définies était assez correcte dans le cas de la prostate mais médiocre dans le cas ORL. Le questionnaire a révélé d'importantes différences dans les méthodes de planification utilisées par les centres. Conclusion : Ces grandes différences peuvent être expliquées par, (1) une connaissance/interprétation variable des définitions ICRU, (2) des appréciations différentes de l'extension tumorale microscopique potentielle, (3) des difficultés dans l'identification du GTV, (4) des différences de concept, et (5) des différences entre la théorie (par ex. la description des marges) et la pratiqué (par ex. les marges dessinées).

Biomassa sustentável de juvenis de pirarucu em tanques-rede de pequeno volume

O objetivo deste trabalho foi estimar a biomassa sustentável de juvenis de pirarucu Arapaima gigas (Cuvier, 1829) mantidos em tanquesrede de pequeno volume. Durante 200 dias os peixes foram estocados em quatro tanques-rede de 1 m³, cada um com biomassa inicial total de 0,84±0,14 kg (21 peixes/tanque-rede). Os tanquesrede foram colocados em um viveiro de 50 m² com renovação constante de água. Os índices do fator de condição, da conversão alimentar, do crescimento específico e do ganho de biomassa revelaram que a biomassa sustentável de juvenis de pirarucu para a criação intensiva em tanques-rede de 1 m³ foi de aproximadamente 29 kg. O comprimento alcançado pelo peixe, no espaço reduzido do tanque-rede, é um fator limitante para manter bons índices zootécnicos.

Sensitive gene expression profiling of human T cell subsets reveals parallel post-thymic differentiation for CD4+ and CD8+ lineages.

The differentiation of CD4(+) or CD8(+) T cells following priming of naive cells is central in the establishment of the immune response against pathogens or tumors. However, our understanding of this complex process and the significance of the multiple subsets of differentiation remains controversial. Gene expression profiling has opened new directions of investigation in immunobiology. Nonetheless, the need for substantial amount of biological material often limits its application range. In this study, we have developed procedures to perform microarray analysis on amplified cDNA from low numbers of cells, including primary T lymphocytes, and applied this technology to the study of CD4 and CD8 lineage differentiation. Gene expression profiling was performed on samples of 1000 cells from 10 different subpopulations, defining the major stages of post-thymic CD4(+) or CD8(+) T cell differentiation. Surprisingly, our data revealed that while CD4(+) and CD8(+) T cell gene expression programs diverge at early stages of differentiation, they become increasingly similar as cells reach a late differentiation stage. This suggests that functional heterogeneity between Ag experienced CD4(+) and CD8(+) T cells is more likely to be located early during post-thymic differentiation, and that late stages of differentiation may represent a common end in the development of T-lymphocytes.

A pipeline approach with spatial information for segmenting multiple sclerosis lesions on brain magnetic resonance imaging

Background: Conventional magnetic resonance imaging (MRI) techniques are highly sensitive to detect multiple sclerosis (MS) plaques, enabling a quantitative assessment of inflammatory activity and lesion load. In quantitative analyses of focal lesions, manual or semi-automated segmentations have been widely used to compute the total number of lesions and the total lesion volume. These techniques, however, are both challenging and time-consuming, being also prone to intra-observer and inter-observer variability.Aim: To develop an automated approach to segment brain tissues and MS lesions from brain MRI images. The goal is to reduce the user interaction and to provide an objective tool that eliminates the inter- and intra-observer variability.Methods: Based on the recent methods developed by Souplet et al. and de Boer et al., we propose a novel pipeline which includes the following steps: bias correction, skull stripping, atlas registration, tissue classification, and lesion segmentation. After the initial pre-processing steps, a MRI scan is automatically segmented into 4 classes: white matter (WM), grey matter (GM), cerebrospinal fluid (CSF) and partial volume. An expectation maximisation method which fits a multivariate Gaussian mixture model to T1-w, T2-w and PD-w images is used for this purpose. Based on the obtained tissue masks and using the estimated GM mean and variance, we apply an intensity threshold to the FLAIR image, which provides the lesion segmentation. With the aim of improving this initial result, spatial information coming from the neighbouring tissue labels is used to refine the final lesion segmentation.Results:The experimental evaluation was performed using real data sets of 1.5T and the corresponding ground truth annotations provided by expert radiologists. The following values were obtained: 64% of true positive (TP) fraction, 80% of false positive (FP) fraction, and an average surface distance of 7.89 mm. The results of our approach were quantitatively compared to our implementations of the works of Souplet et al. and de Boer et al., obtaining higher TP and lower FP values.Conclusion: Promising MS lesion segmentation results have been obtained in terms of TP. However, the high number of FP which is still a well-known problem of all the automated MS lesion segmentation approaches has to be improved in order to use them for the standard clinical practice. Our future work will focus on tackling this issue.