Water balance modelling in a tropical watershed under deciduous forest (Mule Hole, India): Regolith matric storage buffers the groundwater recharge process

Accurate estimations of water balance are needed in semi-arid and sub-humid tropical regions, where water resources are scarce compared to water demand. Evapotranspiration plays a major role in this context, and the difficulty to quantify it precisely leads to major uncertainties in the groundwater recharge assessment, especially in forested catchments. In this paper, we propose to assess the importance of deep unsaturated regolith and water uptake by deep tree roots on the groundwater recharge process by using a lumped conceptual model (COMFORT). The model is calibrated using a 5 year hydrological monitoring of an experimental watershed under dry deciduous forest in South India (Mule Hole watershed). The model was able to simulate the stream discharge as well as the contrasted behaviour of groundwater table along the hillslope. Water balance simulated for a 32 year climatic time series displayed a large year-to-year variability, with alternance of dry and wet phases with a time period of approximately 14 years. On an average, input by the rainfall was 1090 mm year(-1) and the evapotranspiration was about 900 mm year(-1) out of which 100 mm year(-1) was uptake from the deep saprolite horizons. The stream flow was 100 mm year(-1) while the groundwater underflow was 80 mm year(-1). The simulation results suggest that (i) deciduous trees can uptake a significant amount of water from the deep regolith, (ii) this uptake, combined with the spatial variability of regolith depth, can account for the variable lag time between drainage events and groundwater rise observed for the different piezometers and (iii) water table response to recharge is buffered due to the long vertical travel time through the deep vadose zone, which constitutes a major water reservoir. This study stresses the importance of long term observations for the understanding of hydrological processes in tropical forested ecosystems. (C) 2009 Elsevier B.V. All rights reserved.

A new framework for solution of multidimensional population balance equations

A new framework is proposed in this work to solve multidimensional population balance equations (PBEs) using the method of discretization. A continuous PBE is considered as a statement of evolution of one evolving property of particles and conservation of their n internal attributes. Discretization must therefore preserve n + I properties of particles. Continuously distributed population is represented on discrete fixed pivots as in the fixed pivot technique of Kumar and Ramkrishna [1996a. On the solution of population balance equation by discretization-I A fixed pivot technique. Chemical Engineering Science 51(8), 1311-1332] for 1-d PBEs, but instead of the earlier extensions of this technique proposed in the literature which preserve 2(n) properties of non-pivot particles, the new framework requires n + I properties to be preserved. This opens up the use of triangular and tetrahedral elements to solve 2-d and 3-d PBEs, instead of the rectangles and cuboids that are suggested in the literature. Capabilities of computational fluid dynamics and other packages available for generating complex meshes can also be harnessed. The numerical results obtained indeed show the effectiveness of the new framework. It also brings out the hitherto unknown role of directionality of the grid in controlling the accuracy of the numerical solution of multidimensional PBEs. The numerical results obtained show that the quality of the numerical solution can be improved significantly just by altering the directionality of the grid, which does not require any increase in the number of points, or any refinement of the grid, or even redistribution of pivots in space. Directionality of a grid can be altered simply by regrouping of pivots.

Convective heat-transfer rate distributions over a missile shaped body flying at hypersonic speeds

Experiments are carried out with air as the test gas to obtain the surface convective heating rate on a missile shaped body flying at hypersonic speeds. The effect of fins on the surface heating rates of missile frustum is also investigated. The tests are performed in a hypersonic shock tunnel at stagnation enthalpy of 2 MJ/kg and zero degree angle of attack. The experiments are conducted at flow Mach number of 5.75 and 8 with an effective test time of 1 ms. The measured stagnation-point heat-transfer data compares well with the theoretical value estimated using Fay and Riddell expression. The measured heat-transfer rate with fin configuration is slightly higher than that of model without fin. The normalized values of experimentally measured heat transfer rate and Stanton number compare well with the numerically estimated results. (C) 2009 Elsevier Inc. All rights reserved.

Balance of growth factors in the human perinatal lung : Implications for physiological lung development and link to bronchopulmonary dysplasia

The aims of this Thesis was to evaluate the role of proangiogenic placental growth factor (PlGF), antiangiogenic endostatin and lymphangiogenic vascular endothelial growth factor (VEGF) -C as well as the receptors vascular endothelial growth factor receptor (VEGFR) -2 and VEGFR-3 during lung development and in development of lung injury in preterm infants. The studied growth factors were selected due to a close relationship with VEGF-A; a proangiogenic growth factor important in normal lung angiogenesis and lung injury in preterm infants. The thesis study consists of three analyses. I: Lung samples from fetuses, preterm and term infants without lung injury, as well as preterm infants with acute and chronic lung injury were stained by immunohistochemistry for PlGF, endostatin, VEGF-C, VEGFR-2 and VEGFR-3. II: Tracheal aspirate fluid (TAF) was collected in the early postnatal period from a patient population consisting of 59 preterm infants, half developing bronchopulmonary dysplasia (BPD) and half without BPD. PlGF, endostatin and VEGF-C concentrations were measured by commercial enzyme-linked immunosorbent assay (ELISA). III: Cord plasma was collected from very low birth weight (VLBW) (n=92) and term (n=48) infants in conjuncture with birth and endostatin concentrations were measured by ELISA. I: All growth factors and receptors studied were consistently stained in immunohistochemistry throughout development. For endostatin in early respiratory distress syndrome (RDS), no alveolar epithelial or macrophage staining was seen, whereas in late RDS and BPD groups, both alveolar epithelium and macrophages stained positively in approximately half of the samples. VEGFR-2 staining was fairly consistent, except for the fact that capillary endothelial staining in the BPD group was significantly decreased. II: During the first postnatal week in TAF mean PlGF concentrations were stable whereas mean endostatin and VEGF-C concentrations decreased. Higher concentrations of endostatin and VEGF-C correlated with lower birth weight (BW) and associated with administration of antenatal betamethasone. Parameters reflecting prenatal lung inflammation associated with lower PlGF, endostatin and VEGF-C concentrations. A higher mean supplemental fraction of inspired oxygen during the first 2 postnatal weeks (FiO2) correlated with higher endostatin concentrations. III: Endostatin concentrations in term infants were significantly higher than in VLBW infants. In VLBW infants higher endostatin concentrations associated with the development of BPD, this association remained significant after logistic regression analysis. We conclude that PlGF, endostatin and VEGF-C all have a physiological role in the developing lung. Also, the VEGFR-2 expression profile seems to reflect the ongoing differentiation of endothelia during development. Both endostatin and VEGFR-2 seem to be important in the development of BPD. During the latter part of the first postnatal week, preterm infants developing BPD have lower concentrations of VEGF-A in TAF. Our findings of disrupted VEGFR-2 staining in capillary and septal endothelium seen in the BPD group, as well as the increase in endostatin concentrations both in TAF and cord plasma associated with BPD, seem to strengthen the notion that there is a shift in the angiogenic balance towards a more antiangiogenic environment in BPD. These findings support the vascular hypothesis of BPD.

Visual Impairment and Falls Risk in the Elderly

Vision is highly important for balance and gait and visual impairments are significantly associated with locomotion problems and falls in older people. There is now a large body of research linking falls and fall-related injuries with visual problems, some of which are easily remedied by surgery or refractive correction. However there is also evidence that the kind of refractive correction provided (in terms of single-vision or multifocal correction) can also have an effect on fall risk. This chapter provides an overview of the major findings in this area.

Electrocardiographic repolarization variables in detecting myocardial infarction and ischemic injury : From body surface potential mapping to a single lead

The aim of the studies was to improve the diagnostic capability of electrocardiography (ECG) in detecting myocardial ischemic injury with a future goal of an automatic screening and monitoring method for ischemic heart disease. The method of choice was body surface potential mapping (BSPM), containing numerous leads, with intention to find the optimal recording sites and optimal ECG variables for ischemia and myocardial infarction (MI) diagnostics. The studies included 144 patients with prior MI, 79 patients with evolving ischemia, 42 patients with left ventricular hypertrophy (LVH), and 84 healthy controls. Study I examined the depolarization wave in prior MI with respect to MI location. Studies II-V examined the depolarization and repolarization waves in prior MI detection with respect to the Minnesota code, Q-wave status, and study V also with respect to MI location. In study VI the depolarization and repolarization variables were examined in 79 patients in the face of evolving myocardial ischemia and ischemic injury. When analyzed from a single lead at any recording site the results revealed superiority of the repolarization variables over the depolarization variables and over the conventional 12-lead ECG methods, both in the detection of prior MI and evolving ischemic injury. The QT integral, covering both depolarization and repolarization, appeared indifferent to the Q-wave status, the time elapsed from MI, or the MI or ischemia location. In the face of evolving ischemic injury the performance of the QT integral was not hampered even by underlying LVH. The examined depolarization and repolarization variables were effective when recorded in a single site, in contrast to the conventional 12-lead ECG criteria. The inverse spatial correlation of the depolarization and depolarization waves in myocardial ischemia and injury could be reduced into the QT integral variable recorded in a single site on the left flank. In conclusion, the QT integral variable, detectable in a single lead, with optimal recording site on the left flank, was able to detect prior MI and evolving ischemic injury more effectively than the conventional ECG markers. The QT integral, in a single-lead or a small number of leads, offers potential for automated screening of ischemic heart disease, acute ischemia monitoring and therapeutic decision-guiding as well as risk stratification.

Landau-Zener problem with waiting at the minimum gap and related quench dynamics of a many-body system

We discuss a technique for solving the Landau-Zener (LZ) problem of finding the probability of excitation in a two-level system. The idea of time reversal for the Schrodinger equation is employed to obtain the state reached at the final time and hence the excitation probability. Using this method, which can reproduce the well-known expression for the LZ transition probability, we solve a variant of the LZ problem, which involves waiting at the minimum gap for a time t(w); we find an exact expression for the excitation probability as a function of t(w). We provide numerical results to support our analytical expressions. We then discuss the problem of waiting at the quantum critical point of a many-body system and calculate the residual energy generated by the time-dependent Hamiltonian. Finally, we discuss possible experimental realizations of this work.

Reengaging, reenacting and reenvisaging discourses of disaster through public space performance: Austerity, art, and the art of protest

This paper offers a mediation on disaster, recovery, resilience, and restoration of balance, in both a material and a metaphorical sense, when ‘disaster’ befalls not the body politic of the nation but the body personal. In the past few decades, of course, artists, activists and scholars have deliberately tried to avoid describing personal, physical and phenomenological experiences of the disabled body in terms of difficulty and disaster. This has been part of a political move, from a medical model, in which disability, disease and illness are positioned as personal catastrophes, to a social model, in which disability is positioned as a social construct that comes from systems, institutions and infrastructure designed to exclude different bodies. It is a move that is responsible for a certain discomfort people with disabilities, and artists with disabilities, today feel towards performances that deploy disability as a metaphor for disaster, from Hijikata, to Theatre Hora. In the past five years, though, this particular discourse has begun rising again, particularly as people with disabilities fact their own anything but natural disasters as a result of the austerity measures now widespread across the US, UK, Europe and elsewhere. Measures that threaten people’s ability to live, and take part in social and institutional life, in any meaningful way. Measures that, as artist Katherine Araniello notes, also bring additional difficulty, danger, and potential for disaster as they ripple outwards across the tides of familial ties, threatening family, friends, and careers who become bound up in the struggle to do more with less. In this paper, I consider how people with disabilities use performance, particularly public space interventionalist performance, to reengage, renact and reenvisage the discourse of national, economic, environmental or other forms of disaster, the need for austerity, the need to avoid providing people with support for desires and interests as well as basic daily needs, particularly when fraud and corruption is so right, and other such ideas that have become an all too unpleasant reality for many people. Performances, for instance, like Liz Crow’s Bedding Out, where she invited people into her bed – for people with disabilities a symbolic space, which necessarily becomes more a public living room restaurant, office and so forth than a private space when poor mobility means they spend much time it in – to talk about their lives, their difficulties, and dealing with austerity. Or, for instance, like the Bolshy Divas, who mimic public and political policy, reports and advertising paranoia to undermine their discourses about austerity. I examine the effects, politics and ethics of such interventions, including examination of the comparative effect of highly bodied interventions (like Crow’s) and highly disembodied interventions (like the Bolshy Diva’s) in discourses of difficulty, disaster and austerity on a range of target spectator communities.

Understanding data flow and security requirements in wireless Body Area Networks for healthcare

The Body Area Network (BAN) is an emerging technology that focuses on monitoring physiological data in, on and around the human body. BAN technology permits wearable and implanted sensors to collect vital data about the human body and transmit it to other nodes via low-energy communication. In this paper, we investigate interactions in terms of data flows between parties involved in BANs under four different scenarios targeting outdoor and indoor medical environments: hospital, home, emergency and open areas. Based on these scenarios, we identify data flow requirements between BAN elements such as sensors and control units (CUs) and parties involved in BANs such as the patient, doctors, nurses and relatives. Identified requirements are used to generate BAN data flow models. Petri Nets (PNs) are used as the formal modelling language. We check the validity of the models and compare them with the existing related work. Finally, using the models, we identify communication and security requirements based on the most common active and passive attack scenarios.

Long-term effects of physical activity level on changes in healthy body mass index over 12 years in young adult women

Objectives To examine the effects of overall level and timing of physical activity (PA) on changes from a healthy body mass index (BMI) category over 12 years in young adult women. Patients and Methods Participants in the Australian Longitudinal Study on Women's Health (younger cohort, born 1973-1978) completed surveys between 2000 (age 22-27 years) and 2012 (age 34-39 years). Physical activity was measured in 2000, 2003, 2006, and 2009 and was categorized as very low, low, active, or very active at each survey, and a cumulative PA score for this 9-year period was created. Logistic regression was used to examine relationships between PA accumulated across all surveys (cumulative PA model) and PA at each survey (critical periods PA model), with change in BMI category (from healthy to overweight or healthy to obese) from 2000 to 2012. Results In women with a healthy BMI in 2000, there were clear dose-response relationships between accumulated PA and transition to overweight (P=.03) and obesity (P<.01) between 2000 and 2012. The critical periods analysis indicated that very active levels of PA at the 2006 survey (when the women were 28-33 years old) and active or very active PA at the 2009 survey (age 31-36 years) were most protective against transitioning to overweight and obesity. Conclusion These findings confirm that maintenance of very high PA levels throughout young adulthood will significantly reduce the risk of becoming overweight or obese. There seems to be a critical period for maintaining high levels of activity at the life stage when many women face competing demands of caring for infants and young children.

A voltage-sensorless control method to balance the input currents of a three-wire boost rectifier under unbalanced input voltages condition

This paper proposes a control method that can balance the input currents of the three-phase three-wire boost rectifier under unbalanced input voltage condition. The control objective is to operate the rectifier in the high-power-factor mode under balanced input voltage condition but to give overriding priority to the current balance function in case of unbalance in the input voltage. The control structure has been divided into two major functional blocks. The inner loop current-mode controller implements resistor emulation to achieve high-power-factor operation on each of the two orthogonal axes of the stationary reference frame. The outer control loop performs magnitude scaling and phase-shifting operations on current of one of the axes to make it balanced with the current on the other axis. The coefficients of scaling and shifting functions are determined by two closed-loop prportional-integral (PI) controllers that impose the conditions of input current balance as PI references. The control algorithm is simple and high performing. It does not require input voltage sensing and transformation of the control variables into a rotating reference frame. The simulation results on a MATLAB-SIMULINK platform validate the proposed control strategy. In implementation Texas Instrument's digital signal processor TMS320F24OF is used as the digital controller. The control algorithm for high-power-factor operation is tested on a prototype boost rectifier under nominal and unbalanced input voltage conditions.

Determination of mixture composition by the float balance

Herein is described a method by which component gases can be weighed as they are added one by one to a gas mixture. The float balance, designed for the purpose, is capable of determining a maximum mass of about 3 kg of a gas mixture contained in a cylinder of mass about 5 kg with a sensitivity of ±0·1 g mm-1 of the stem height.