REPRESENTING THE DISPERSION OF EMISSIONS FROM AIRCRAFT ON RUNWAYS

Aircraft in their takeoff ground run constitute an unavoidable strong source of emissions subject to a highly variable motion. The intermittent nature of release makes it difficult to measure the emissions and establish their impact on mean concentrations in the vicinity of airports. Practically, it is also difficult to perform experimental studies near taxiways and runways. Remote observations have nevertheless recently been obtained by a rapidly-swept UV Lidar, and analysis of these has necessitated and informed a parallel modelling effort. Aircraft exhausts disperse in a complex manner, as they are subject not only to transport processes of the ambient atmosphere, but also to those associated with the aircraft itself (with diffusion in ambient turbulence to be expected once turbulence resulting from the aircraft falls to ambient levels). They have a downstream Lagrangian momentum associated with the engine thrust, and steadily acquire a vertical momentum as a result of their buoyancy. Exhaust streams merge and interact strongly with the ground to form a common emission plume within about a wingspan downstream of engines’ exits. Before the aircraft reaches a threshold speed, is rotated upward and lifts off, the downstream (thrust) forcing and upstream source acceleration are approximately constant, and a first-order nonlinear partial differential equation may be expressed capturing the turbulent diffusion of the plume in the reference frame of the source. The downstream forcing exceeds the buoyant forcing, so the plume remains in contact with the ground, but is heightened and narrowed by buoyant rise. During rotation and liftoff, the net downstream forcing declines as a significant airframe drag arises, and the source acceleration plummets. More importantly, lift on the airframe and the associated shed circulation cause exhausts to move downward and, in proximity to ground, outward, so their dynamics decouple from those of exhausts released earlier, with re-coupling unlikely before the aircraft has turned in its flight path. Once rotation is initiated, this argues for a simplifying (and partly analytic) treatment of the exhaust plume generated earlier, such that the turbulent diffusion of a given elemental plume segment is taken to match that of an infinitely long flow tube (with the latter ascribed the same buoyancy density and downstream Lagrangian momentum density – or mass flux – throughout)

Uji Diagnostik Prokalsitonin Dibanding Kultur Darah Sebagai Baku Emas Untuk Diagnostik Sepsis Bakterial Di Rsup Dr.kariadi

Background: Sepsis is a serious health problem arround the world because the late diagnosis can threathen life. Diagnosis by blood culture as the gold standard need 2-3 days.That's why more rapid and accurate diagnostic method are needed which is Procalcitonin test This study was aim to determine sensitivity,spesificity,positive predictive value,and negative predictive value of Procalcitonin test compared to blood culture.Methods: Data used in this study is patients diagnosed sepsis clinically in Kariadi hospital Semarang in 2011. Study subjects totaled 27 people aged less than 1 year till 87 years. Results of procalcitonin test with determined cut- off point compared with the blood culture results , then assess the diagnostic procalcitonin .Results: At 2 ng/ml obtained sensitivity 66,6%,spesificity 44,4%, positive predictive value 37,5%, negative predictive value 72,7%,and accuration 51,85%.Conclusion: The sensitivity,spesificity,positive predictive value,negative predictive value,and accuration of Procalcitonin test for diagnosing sepsis in Kariadi hospital are low

Exploring views on satisfaction with life in young children with chronic illness: an innovative approach to the collection of self-report data from children under 11

The objective of this study was to explore young children’s views on the impact of chronic illness on their life in order to inform future development of a patient-based self-report health outcome measure. We describe an approach to facilitating self-report views from young children with chronic illness. A board game was designed in order to obtain qualitative data from 39 children with a range of chronic illness conditions and 38 healthy controls ranging in age from 3 to 11 years. The format was effective in engaging young children in a self-report process of determining satisfaction with life and identified nine domains. The board game enabled children aged 5–11 years with chronic illness to describe the effects of living with illness on home, family, friends, school and life in general. It generated direct, non-interpreted material from children who, because of their age, may have been considered unable or limited their ability to discuss and describe how they feel. Obtaining this information for children aged 4 and under continues to be a challenge

Practices of strength and conditioning coaches: a snapshot from different sports, countries and expertise levels

This study describes the practices of strength and conditioning coaches (SCCs) from different sports, countries and expertise levels. One-hundred and fifty-six SCCs (31.9 + 8.9 years old) completed an online survey, consisting of 40 questions (36 fixed response and 4 open-ended), with eight sections: (a) background information, (b) muscular strength and power development, (c) speed development, (d) plyometrics, (e) flexibility development, (f) physical testing, (g) technology use, and (h) programming and any additional comments. Responses were received from 48 sports and 17 countries. This study provides exploratory evidence incorporating responses primarily in soccer (45%), track and field (30%), volleyball (23%), golf (17%) and tennis (17%). A Bachelor’s degree or higher were held by 99% of SCCs, of which 94% were in a sports science related field, and 71% held a strength and conditioning related certification or accreditation. Periodization strategies and physical testing were used by 94% of SCCs. The hang clean (82%), power clean (76%), and clean high pull (63%) were the most commonly prescribed Olympic Weightlifting exercises. Multiple hops/lunges (84%) were the most commonly prescribed plyometrics exercises. For open ended questions, 40% of SCCs wanted to integrate more technology into their programs, whereas, 30% of coaches believed technology will be the main future trend in strength and conditioning. SCCs from different sports, countries and expertise levels can use the information presented in this study to review their current practices and potentially provide a source of new ideas for diversifying or modifying future practices too

Modelling the atomic structure of very high-density amorphous ice

The structure of very high-density amorphous (VHDA) ice has been modelled by positionally disordering three crystalline phases, namely ice IV, VI and XII. These phases were chosen because only they are stable or metastable in the region of the ice phase diagram where VHDA ice is formed, and their densities are comparable to that of VHDA ice. An excellent fit to the medium range of the experimentally observed pair-correlation function g(r) of VHDA ice was obtained by introducing disorder into the positions of the H2O molecules, as well as small amounts of molecular rotational disorder, disorder in the O--H bond lengths and disorder in the H--O--H bond angles. The low-k behaviour of the experimental structure factor, S(k), is also very well reproduced by this disordered-crystal model. The fraction of each phase present in the best-fit disordered model is very close to that observed in the probable crystallization products of VHDA ice. In particular, only negligible amounts of ice IV are predicted, in accordance with experimental observation.Comment: 4 pages, 3 figures, 1 table, v2: changes made in response to referees' comments, the justification for using certain ice phases is improved, and ice IV is now disordered as wel

Seasonal variation and impact of waste-water lagoons as larval habitat on the population dynamics of Culicoides sonorensis (Diptera:Ceratpogonidae) at two dairy farms in northern California.

The Sacramento (northern Central) Valley of California (CA) has a hot Mediterranean climate and a diverse ecological landscape that is impacted extensively by human activities, which include the intensive farming of crops and livestock. Waste-water ponds, marshes, and irrigated fields associated with these agricultural activities provide abundant larval habitats for C. sonorensis midges, in addition to those sites that exist in the natural environment. Within this region, C. sonorensis is an important vector of bluetongue (BTV) and related viruses that adversely affect the international trade and movement of livestock, the economics of livestock production, and animal welfare. To characterize the seasonal dynamics of immature and adult C. sonorensis populations, abundance was monitored intensively on two dairy farms in the Sacramento Valley from August 2012- to July 2013. Adults were sampled every two weeks for 52 weeks by trapping (CDC style traps without light and baited with dry-ice) along N-S and E-W transects on each farm. One farm had large operational waste-water lagoons, whereas the lagoon on the other farm was drained and remained dry during the study. Spring emergence and seasonal abundance of adult C. sonorensis on both farms coincided with rising vernal temperature. Paradoxically, the abundance of midges on the farm without a functioning waste-water lagoon was increased as compared to abundance on the farm with a waste-water lagoon system, indicating that this infrastructure may not serve as the sole, or even the primary larval habitat. Adult midges disappeared from both farms from late November until May; however, low numbers of parous female midges were detected in traps set during daylight in the inter-seasonal winter period. This latter finding is especially critical as it provides a potential mechanism for the "overwintering" of BTV in temperate regions such as northern CA. Precise documentation of temporal changes in the annual abundance and dispersal of Culicoides midges is essential for the creation of models to predict BTV infection of livestock and to develop sound abatement strategies

Striped Jets in Post Neutron Star Merger Systems

Models invoking magnetic reconnection as the particle acceleration mechanism within relativistic jets often adopt a gradual energy dissipation profile within the jet. However, such a profile has yet to be reproduced in first-principles simulations. Here, we perform a suite of 3D general relativistic magnetohydrodynamic simulations of post-neutron star merger disks with an initially purely toroidal magnetic field. We explore the variations in both the microphysics (e.g., nuclear recombination, neutrino emission) and system parameters (e.g., disk mass). In all our simulations, we find the formation of magnetically striped jets. The stripes result from the reversals in the poloidal magnetic flux polarity generated in the accretion disk. The simulations display large variations in the distributions of stripe duration, $\tau$, and power, $\langle P_{\Phi} \rangle$. We find that more massive disks produce more powerful stripes, the most powerful of which reaches $\langle P_{\Phi} \rangle \sim 10^{49}$~erg~s$^{-1}$ at $\tau \sim 20$~ms. The power and variability that result from the magnetic reconnection of the stripes agree with those inferred in short duration gamma-ray bursts. We find that the dissipation profile of the cumulative energy is roughly a power-law in both radial distance, $z$, and $\tau$, with the slope in the range, $\sim 1.7-3$; more massive disks display larger slopes