Evaluation of the performance of TDR and capacitance techniques for soil moisture measurement

Though researchers have employed various techniques (gravimetric, electromagnetic, neutron scattering, heat pulse, micro-wave and optical remote sensing techniques) for soil moisture measurement, dielectric based techniques (Time Domain Reflectometry, TDR, and capacitance technique, CT) have gained much more popularity, mainly due to revolutionary developments in the field of electronics and data communication systems. However, suitability and relative performance of these techniques for moisture measurement of soils is a point of debate. Hence, in order to address this issue, extensive studies were conducted on the soils of entirely different characteristics, compacted at various compaction states (dry density and water content) by employing TDR and capacitance probes. Subsequently, the dielectric constant of the soil and its bulk electrical conductivity were obtained using these probes and compared against each other and that computed from Topp’s equation, which is a well-established relationship between the dielectric constant of the soil and its volumetric moisture content. An attempt was also made to correlate Ka values obtained from the dielectric techniques and Topp’s equation with that of Time Propagation (TP) mixing model, which incorporates in it the properties of the soil matrix as well. It has been observed that Ka-TDR matches well with the Ka-Topp and Ka-TP, while the best match has been observed between Ka-TDR and Ka- Topp as compared to the Ka-CT. As such, the study demonstrates, clearly, that Topp’s equation, which ignores the soil specific parameters, is capable of determining the soil moisture content appropriately . This study proposes an empirical equation which relates dielectric constants obtained from Topp's equation to those obtained from the TDR, capacitance technique and TP mixing model. Such a relationship can be further utilized for estimating the volumetric soil moisture content

Simultaneous RPD and SVC Placement in Power Systems for Voltage Stability Improvement Using a Fuzzy Weighted Seeker Optimization Algorithm

Voltage stability issues are growing challenges in many modern power systems. This paper proposes optimizing the size and location of Static VAR Compensator (SVC) devices using a Fuzzy Weighted Seeker Optimization Algorithm (FWSOA), as an effective solution to overcome such issues. Although the primary purpose of SVC is bus voltage regulation, it can also be useful for voltage stability enhancement and even real power losses reduction in the network. To this aim, a multi-objective function is presented which includes voltage profile improvement, Voltage Stability Margin (VSM) enhancement and minimization of active power losses. Voltage stability is very close to Reactive Power Dispatch (RPD) in the network. Therefore, in addition to voltage regulation with locating SVCs, considering all of the other control variables including excitation settings of generators, tap positions of tap changing transformers and reactive power output of fixed capacitors in the network, simultaneous RPD and SVC placement will be achieved. Simulation results on IEEE 14 and 57-bus test systems, applying Genetic Algorithm (GA), Particle Swarm Optimization (PSO), Seeker Optimization Algorithm (SOA) and FWSOA verify the efficiency of FWSOA for the above claims

A model-based approach for estimation of changes in lumbar segmental kinematics associated with alterations in trunk neuromuscular strategy

This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this recordThe geometrical information from imaging, if combined with optimization-based methods of neuromuscular assessment, may provide a unique platform for personalized assessment of trunk neuromuscular behavior. Such a method, however, is feasible only if differences in lumbar spine kinematics due to differences in trunk neuromuscular behavior can be captured by the current imaging techniques. A finite element model of the spine within an optimization procedure was used to estimate segmental kinematics of lumbar spine associated with five different hypothetical trunk neuromuscular strategies (TNSs). Each TNS optimized one aspect of lower back biomechanics and was assumed to either represent the TNS of asymptomatic persons or a neuromuscular abnormality. For each TNS, the segmental kinematics of lumbar spine was estimated for a single static trunk flexed posture involving, respectively, 40° and 10° of thoracic and pelvic rotations. Minimum changes in the angular and translational deformations of a motion segment with alterations in TNS ranged from 0° to 0.5° and 0 mm to 0.04 mm, respectively. Maximum changes in the angular and translational deformations of a motion segment with alterations in neuromuscular strategy ranged from 2.4° to 7.5° and 0.11 mm to 0.39 mm, respectively. The differences in kinematics of lumbar segments between each combination of two TNSs in 97% of cases for angular deformation and 55% of cases for translational deformation were within the reported accuracy of current imaging techniques. Combined imaging and computational modeling appears to have potentials for predicting alterations in neuromuscular strategies.This work was supported, in part, by an award (5R03HD086512-02) from the National Center for Medical Rehabilitation Research (NIH-NICHD) and the Office of the Assistant Secretary of Defense for Health Affairs, through the Peer Reviewed Orthopaedic Research Program (award #W81XWH-14-2-0144)

Preoperative assessment of meningioma aggressiveness by Thallium-201 brain SPECT

Introduction: Meningioma is usually a benign brain tumor, but sometimes with aggressive course. The aim of this study was to assess the ability of 201Tl Brain SPECT to differentiate the pathologic grade of meningioma preoperatively. Methods: Thirty lesions in 28 patients were evaluated in this study. Early (20 minutes) and late (3 hours) brain SPECT images were performed and early uptake ratio (EUR), late uptake ratio (LUR) and retention index (RI) were calculated. All patients were operated and pathologic grade of tumors were defined according to World Health Organization grading system. Results: SPECT results were compared in different pathologic groups. Data analysis clarified no significant difference of EUR in benign and aggressive meningioma (P=0.2). However LUR and RI were significantly higher in aggressive tumors (P=0.001 and P=0.02, respectively). Conclusion: According to our data Tl-201 Brain SPECT with early and late imaging has 80 sensitivity and specificity to differentiate malignant from benign meningioma

Evaluation of thyroid hormones in patients with lead poisoning

Background: Each toxic agent results in unique presentations, depending on what neurophysiological changes occur following exposure. Scientific understanding of lead toxicity in the organ systems and at low levels of exposure continues to evolve. However, effects of lead poisoning on the thyroid gland function are controversial. In this descriptive study, changes in thyroid hormones in patients with lead poisoning were compared with patients with opioid addiction and healthy individual who were matched for age and sex. Methods: In this descriptive study, which was conducted from March 2016 to February 2017 in Loghman Hakim Hospital in Tehran, ninety patients were evaluated using convenient sampling method for lead and thyroid hormones levels. The levels of lead and thyroid hormones were evaluated using standard laboratory method, in thirty male patients with lead poisoning, thirty male patients with opioid addiction referring to addiction treatment center and thirty healthy male referring to a blood donation center who were matcAhed for age. Thyroid function parameters in patients with lead toxicity were compared with those of control groups. Results: The lead level in the lead toxicity group was 57.5±23.5 µg/dl, in the first control group with opium addiction 7.8±3.8 µg/dl and in the healthy male referring to a blood donation center, 5.9±9 µg/dl. Thyroid stimulating hormone (TSH) was significantly lower in patients with lead poisoning (0.2±0.01 Milli-International Units Per Liter (mIU/L) than in the patients with opioid addiction (2.4±1/05 mIU/L) and healthy male referring to a blood donation center (2.3±0.01 mIU/L) (P= 0.04), and thyroxine hormone (T4) was significantly higher in patients with lead poisoning (17.8±2.6 µg/dl) than in the patients with opioid addiction (8.8±1/9 µg/dl) and healthy male referring to a blood donation center (7.4±3.5 µg/dl) (P= 0.02). Conclusion: Lead toxicity has an effect on thyroid function and it reduces thyroid stimulating hormone and increases thyroxin levels. Clinicians should be aware of the potential hazardous effects of lead on the thyroid and mechanisms through which lead causes these effects on thyroid function need to be elucidated. Keywords: lead poisoning, opium, thyroid function test

O ensino das ciências experimentais no liceu, em Portugal, na I República (1910-1926)

O ensino das ciências experimentais (ECE) em Portugal ficou, como pretendemos demonstrar, fortemente marcado pela instauração da República, que comemorou no ano transacto o seu centenário. A República de 1910 pretendeu reformar toda a mentalidade portuguesa, através do pilar base – a educação – pela qual seria capaz de sacudir a nossa maneira de ser, lançando desta forma o país para um progresso de nível europeu. O estudo a que nos propomos, uma investigação documental no domínio da História da Ciência1, visa aprofundar os conhecimentos existentes sobre esta época e perceber o impacto da reforma do ECE, principalmente nos Liceus, caracterizando as principais figuras, políticas e docentes responsáveis pela sua conceptualização e aplicação. Através desta investigação procuraremos lançar as primeiras bases para descobrir as origens deste pensamento, querendo ainda comparar os fundamentos psicopedagógicos, epistemológicos e sociológicos da época com as principais ideias actualmente presentes no ensino da Ciência. Com este trabalho pretendemos, num primeiro momento, apresentar e divulgar o desenho da investigação e os seus objectivos, na procura de estabelecer parcerias e receber contributos da comunidade académica interessada por esta problemática

Neutrophils in cancer: neutral no more

Neutrophils are indispensable antagonists of microbial infection and facilitators of wound healing. In the cancer setting, a newfound appreciation for neutrophils has come into view. The traditionally held belief that neutrophils are inert bystanders is being challenged by the recent literature. Emerging evidence indicates that tumours manipulate neutrophils, sometimes early in their differentiation process, to create diverse phenotypic and functional polarization states able to alter tumour behaviour. In this Review, we discuss the involvement of neutrophils in cancer initiation and progression, and their potential as clinical biomarkers and therapeutic targets

Angiostatin anti-angiogenesis requires IL-12: The innate immune system as a key target

© 2009 Albini et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

Stromal Cell-Derived Factor-1/CXCL12 Contributes to MMTV-Wnt1 Tumor Growth Involving Gr1+CD11b+ Cells

BACKGROUND: Histological examinations of MMTV-Wnt1 tumors reveal drastic differences in the tumor vasculature when compared to MMTV-Her2 tumors. However, these differences have not been formally described, nor have any angiogenic factors been implicated to be involved in the Wnt1 tumors. METHODOLOGY/PRINCIPAL FINDINGS: Here, we show that MMTV-Wnt1 tumors were more vascularized than MMTV-Her2 tumors, and this correlated with significantly higher expression of a CXC chemokine, stromal cell-derived factor-1 (SDF1/CXCL12) but not with VEGFA. Isolation of various cell types from Wnt1 tumors revealed that SDF1 was produced by both tumor myoepithelial cells and stromal cells, whereas Her2 tumors lacked myoepithelial cells and contained significantly less stroma. The growth of Wnt1 tumors, but not Her2 tumors, was inhibited by a neutralizing antibody to SDF1, but not by neutralization of VEGFA. Anti-SDF1 treatment decreased the proportion of infiltrating Gr1(+) myeloid cells in the Wnt1 tumors, which correlated with a decrease in the percentage of endothelial cells. The involvement of Gr1(+) cells was evident from the retardation of Wnt1 tumor growth following in vivo depletion of these cells with an anti-Gr1-specific antibody. This degree of inhibition on Wnt1 tumor growth was comparable, but not additive, to the effect observed with anti-SDF1, indicative of overlapping mechanisms of inhibition. In contrast, Her2 tumors were not affected by the depletion of Gr1(+) cells. CONCLUSIONS/SIGNIFICANCE: We demonstrated that SDF1 is important for Wnt1, but not for HER2, in inducing murine mammary tumor and the role of SDF1 in tumorigenesis involves Gr1(+) myeloid cells to facilitate growth and/or angiogenesis