Analog Model Research Articles

PDG48 AN ANALYSIS OF THE DANISH MODEL FOR ANALOGUE COMPETITION OF HOSPITAL MEDICINE BASED ON THE THERAPEUTIC AREA, HEPATITIS C

The expenses for hospital pharmaceuticals in Denmark has increased more than 80% the last decade. The increased expenditure is particularity caused by new and expensive patent-protected medicine. Amgros carries out EU-tender calls for 98% of hospital medicine used at public hospitals in Denmark. The opportunity to achieve price discounts on patent-protected pharmaceuticals through tender calls are minimal due to the limited competition. In order to accommodate this, a unique analogue competition model was developed by Amgros and the Danish Regions. The purpose of this study was to explore the effects of the analogue competition model on pharmaceutical prices in the therapeutic area hepatitis C in the period from 2014-2018. The study was designed as a case study including semi-structured interviews with relevant stakeholders in the industry, Danish Regions, and Amgros. Quantitative data including both list prices and actual purchase prices were withdrawn with special permission from Amgros´ database. The qualitative and quantitative analysis showed that the price for one hepatitis C treatment decreased 77% (from 531.406 DKK to 121.798 DKK per patient) for genotype 1 and 32% (from 531.406 DKK to 363.780 DKK per patient) for genotype 3 within the period 2014-2018. Important factors leading to the price decreases were the following: the therapeutic treatment guidelines produced by the Danish Medicines Council equalling the medicine at ATC level 5, the number of pharmaceuticals for each disease genotype on the market at each tender, the incentive structure created by the Amgros tender system with possibilities of being ranked as first choice with an 75% market share, and the size of the patient population. The analysis showed that the analogue model was effective in creating an oligopoly competition market situation within the therapeutic area hepatitis C.

Modification of the solar heating system diagnostic method under operating conditions

One of the problems with the operation of solar heating systems is the variable capacity of the system dependent on the prevailing operating conditions. One of the methods for increasing the capacity of a solar system is to control the volume flow of the working medium. Volume flow of working medium in solar heating installation should be follow operating conditions. Designing a continuous control system based eg. on the PID controller requires knowledge of the dynamic properties of a solar system under operating conditions: gain coefficient, equivalent time constant and delay time of the solar collector response to a change in solar radiation intensity and the inlet temperature of a working medium. To date, the delay time has been omitted in the analyses. It is necessary to know the value of the delay time for proper design of the solar system controls, because the object response cannot be simultaneous with the moment of the input function. The paper presents the method for determining the dynamic properties of a solar system under operating conditions. The method is based on the comparison of two models: an analog model based on the energy balance of a collector and a digital model developed with the use of parametric identification based on a short-term measurement of solar radiation intensity and working medium temperatures. In the collector analog model, on the basis of the design and operating parameters of the collector, the transport delay time has been defined, which is an innovative aspect of this study. The modified analog collector model was verified on the basis of the step response determined experimentally in accordance with the applicable ISO 9806: 2017 standard. A very good convergence of the model with actual data was achieved for the time constant – 87%, effective thermal capacity – 85.9%, and the delay time – 96%. Practical application of the modified diagnostic method is presented on the example of a solar heating system composed of five flat-plate collectors with a total absorber area of 10 m2.

ФІНАНСОВІ ПОТОКИ В ЛОГІСТИЧНИХ СИСТЕМАХ ВИРОБНИЧИХ ПІДПРИЄМСТВ

Обґрунтовано значущість дослідження й оцінки фінансових потоків у логістичних системах виробничих підприємств. Розглянуто наявні думки щодо розуміння дослідниками дефініції «фінансовий потік» і вартісні показники для його оцінки. Вказано на безпосередній зв’язок фінансових потоків із грошовими.На основі використання принципу «сплата грошей — одержання грошей» обґрунтовано, що фінансові потоки є однією з головних компонент логістичних систем виробничих підприємств. Зазначено, що фінансові потоки утворюються і використовуються саме для забезпечення нормального режиму функціонування логістичних систем підприємств. Запропоновано визначення поняття «логістичний фінансовий потік» і наведено основні показники його оцінки.З використанням аналогової моделі логістичної системи виробничого підприємства досліджено реальні місця утворення фінансових потоків, зокрема екзо- і ендогенного походження. Обґрунтовано, що їхнє утворення пов’язано з просуванням матеріальних цінностей, управлінням логістичними інформаційними потоками, оплатою відсотків за використання позичкового капіталу, форс-мажорними ситуаціями, псуванням матеріальних цінностей, логістичними ризиками, утворенням запасів сировини, матеріалів і готової продукції, незавершеним виробництвом і розвитком інфраструктури логістичної системи підприємства.Запропоновано класифікацію логістичних фінансових потоків за фазами переміщення матеріально-технічних цінностей і математичну модель для обчислення їхньої величини упродовж визначеного періоду.З огляду на результати дослідження логістичної діяльності вітчизняних виробничих підприємств визначено кількісні характеристики логістичних фінансових потоків — обсяг, вартість і частку в загальному обсязі фінансового потоку. Обчислено чисельні значення фінансових потоків для усіх фаз руху матеріально-технічних цінностей у межах логістичних систем виробничих підприємств, що досліджувалися.

The Information Loss Problem: An Analogue Gravity Perspective

Analogue gravity can be used to reproduce the phenomenology of quantum field theory in curved spacetime and in particular phenomena such as cosmological particle creation and Hawking radiation. In black hole physics, taking into account the backreaction of such effects on the metric requires an extension to semiclassical gravity and leads to an apparent inconsistency in the theory: the black hole evaporation induces a breakdown of the unitary quantum evolution leading to the so-called information loss problem. Here, we show that analogue gravity can provide an interesting perspective on the resolution of this problem, albeit the backreaction in analogue systems is not described by semiclassical Einstein equations. In particular, by looking at the simpler problem of cosmological particle creation, we show, in the context of Bose–Einstein condensates analogue gravity, that the emerging analogue geometry and quasi-particles have correlations due to the quantum nature of the atomic degrees of freedom underlying the emergent spacetime. The quantum evolution is, of course, always unitary, but on the whole Hilbert space, which cannot be exactly factorized a posteriori in geometry and quasi-particle components. In analogy, in a black hole evaporation one should expect a continuous process creating correlations between the Hawking quanta and the microscopic quantum degrees of freedom of spacetime, implying that only a full quantum gravity treatment would be able to resolve the information loss problem by proving the unitary evolution on the full Hilbert space.

Analog models for holographic transport

The gauge-gravity duality and analog gravity both relate a condensed matter system to a gravitational theory. This makes it possible to use gravity as an intermediary to establish a relation between two different condensed matter systems: The strongly coupled system from the gauge-gravity duality and the weakly coupled gravitational analog.We here offer some examples for relations between observables in the two different condensed matter systems. In particular, we show that in some cases Green's functions and first order transport coefficients in holographic models are of the same form as those in an analog gravitational system, which allows in principle to obtain the former by measuring the latter.

Simulating seeded vacuum decay in a cold atom system

We propose to test the concept of seeded vacuum decay in cosmology using an analogue gravity Bose-Einstein condensate system. The role of the nucleation seed is played by a vortex within the condensate. We present two complementary theoretical analyses that demonstrate seeded decay is the dominant decay mechanism of the false vacuum. First, we adapt the standard instanton methods to the Gross-Pitaevskii equation. Second, we use the truncated Wigner method to study vacuum decay.

Spacelike character of the Minkowski four-momentum in analog gravity

In analog gravity the recent experiment of Drori {\it et al.} [Phys. Rev. Lett. {\bf 122}, 010404 (2019)] is impressive, as it shows how the emission of two Hawking quanta emitted in opposite directions lead to measurable consequences in the medium's rest system in a straightforward way. This result raises however the following problem: how can this experiment be explained in terms of classical electrodynamics? There must necessarily exist such an explanation (the experiment is after all classical); otherwise classical electrodynamics would be an incomplete theory. This is the main topic of the present paper. We propose that the measured effect is a demonstration of the spacelike character of the Minkowski four-momentum. Moreover, we extend the discussion by analyzing a Gedanken experiment (making use of the Kerr effect as a formal agency), to illustrate the transition from subluminal to superluminal phenomena in a straightforward way. Finally, we emphasize the close relationship that exists between the spacelike Minkowski momentum and the anomalous Doppler effect.

Digital interface in Indonesia’s public service broadcasting: Its initiatives and regulatory challenges

Abstract The merging of broadcast platforms, the Internet and social media has challenged the former state-owned broadcasters of Indonesia to find new content strategies and forms suited to the networked media environment. Over the past decade, the arrival of digital technology and rapid growth of social media has broken down the previous linear model of service delivery in Indonesian broadcasting. However, national policy on this issue remains lacking. At present, the Indonesian Broadcast Law (Law No. 32 of 2002) only gives the country’s public radio an ability to use the spectrum in the analogue model. Digital migration, as well as legal protection of social media services, remains an ongoing debate among policy-makers, that will allow free market competition, in particular to opportune the interface of service providers and content producers. Drawing from semi-structured interviews, observations and regulatory reviews, this article broadly investigates the introduction of digital interfaces in the new public service broadcasters of Indonesia, with particular focus on the process through which Indonesian PSBs have embraced the digital media environment to enable the flow of information and public participation between the media entities and their publics. In this article, I present both technology and regulatory perspectives by emphasizing the dynamics of the digital media modes of public service delivery, particularly those through which analogue broadcasts and social media have sought new ways to intertwine. In detail, I will examine certain interactive services applied by Radio Republik Indonesia (RRI), the flagship of Indonesian national public radio, namely RRI-Play, RRI.co.id and RRI-Net, to manage audience participation. Since 2016, these digital platforms have mediated public access to RRI content, generated data on media users, and monitored technological performance. In inspecting these platforms, I refer firstly to the normative debate of public service broadcasters as ‘deliberative public sphere’ before segueing into the three public-service functions that are important in social network media landscape: curation, moderation and monitoring. Furthermore, this article analyses problems behind the regulatory design of Indonesian public-service media within the context of digital broadcasts in the country.

Origin and development of true karst valleys in response to late Holocene sea‐level change, the Transverse Glades of southeast Florida, USA

AbstractThe Miami Limestone is an oolite depositional body that is used as an analog model for geological interpretation of the rock record. Barrier‐bar complex, oolite banks, extensive bryozoan flats and tidal creeks, referred to as transverse glades, have been described. High‐resolution LiDAR data are used to produce unprecedented, detailed topographic maps of the transverse glades in the southern Atlantic Coastal Ridge. These maps were originally used to calculate historic discharge from the Everglades but revealed features inconsistent with the prevailing theory that the topography is of a depositional origin. Field observations verified an epikarst terrain truncated by collapsed subsurface conduits creating valleys, previously described as palaeotidal creeks. Observations of the 12 southern tidal creeks or transverse glades provided a sequence of six stages in the development of these karst valleys. After Late Pleistocene deposition of the Miami Limestone, sea‐level dropped producing conditions of: (a) epikarst which reduced the surface elevation preferentially, forming the southern Everglades Basin and modifying Biscayne Bay and Florida Bay precursor basins and (b) downward water movement producing vertical solution features. As Holocene sea‐level approached the South Florida carbonate platform margin a freshwater lens formed and groundwater movement became horizontal. Two sets of cavernous zones developed during the Middle and Late Holocene. Solution pipes and dolines provide a connection between the surface and groundwater along alignments which delineate subsurface conduits. Stages of valley formation are associated with the collapse of these conduits first forming a series of pocket valleys followed by narrow blind valleys and half blind or through valleys linking the Everglades to the coastal plain. Valleys then expanded in width until: (a) completion of cavernous zone collapse, (b) most boulder fields and valley margins reduced by weathering and (c) the valleys filled with wetland soils.

Aeolian transport of viable microbial life across the Atacama Desert, Chile: Implications for Mars

Here we inspect whether microbial life may disperse using dust transported by wind in the Atacama Desert in northern Chile, a well-known Mars analog model. By setting a simple experiment across the hyperarid core of the Atacama we found that a number of viable bacteria and fungi are in fact able to traverse the driest and most UV irradiated desert on Earth unscathed using wind-transported dust, particularly in the later afternoon hours. This finding suggests that microbial life on Mars, extant or past, may have similarly benefited from aeolian transport to move across the planet and find suitable habitats to thrive and evolve.

Is the SNARC a boojum?

In this essay, the author notes that for the past half-century, psychologists have examined how humans make use of spatial representations when making judgments about numerical properties of sets of items. This line of work was initiated by Frank Restle (1970), who asked college students at Indiana University to choose the larger number, either the sum of A + B or C, as rapidly as possible. Restle found that the timing of people's choices fit an analog model of numerical judgment that had been proposed a few years earlier (Moyer & Landauer, 1967) and that people seemed to judge the magnitude of numbers by their position on a mental number line. The hypothetical number line is now called the "mental number line," and the effect on latency to respond to questions about numbers that results from use of the mental number line has been labeled the "Spatial Numerical Association of Response Codes" or SNARC for short. The author notes that she has parodied Frank Beach's (1950) title for his classic essay about the state of comparative psychology at the mid-20th century for the title of this piece. Beach, in turn, was inspired by Lewis Carroll's nonsense poem, " The Hunting of the Snark," published in 1876. The poem chronicles "the impossible voyage of an improbable crew to find an inconceivable creature," the snark. According to the poem, most species of snarks are relatively harmless. The boojum, however, is a dangerous snark, because those who catch sight of a boojum "suddenly vanish away." Here, the author wants to turn the meaning of the homonym SNARC a bit to suggest that the SNARC might itself vanish, perhaps to metamorphose into a more complex entity. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Statistical Downscaling of Urban-scale Air Temperatures Using an Analog Model Output Statistics Technique

This study was conducted to evaluate the suitability of an analog model output statistics (MOS) downscaling technique for urban-scale meteorology research and compares this MOS-Analog technique with the sliding window technique. We downscaled air temperatures forecasted for the Seoul metropolitan area from 1.5 km resolution (using data from the Unified Model-Local Data Assimilation and Prediction System, UM-LDAPS) to 25 m resolution using the analog MOS technique described in the paper. The support vector machine (SVM) technique was employed for empirical computational modeling, using urban surface parameters calculated using the Climate Analysis Seoul (CAS) workbench and automated weather station (AWS) observational data as training data. The comparison of the downscaled prediction results with the AWS observations for the periods of July/August 2016 and 2017 resulted in a lower root mean square error (RMSE) and higher correlation coefficients (CC) than those obtained for the LDAPS prediction results. The prediction performance was also stable for September, during which precipitation episodes and seasonal fluctuations occurred. The results of this study demonstrate that the proposed technique, which overcomes the limitations of the sliding window technique, is applicable to urban-scale meteorology research and potentially applicable other areas.

A Moderate Daily Dose of Resveratrol Mitigates Muscle Deconditioning in a Martian Gravity Analog.

While there is a relatively good understanding of the effects of microgravity on human physiology based on five decades of experience, the physiological consequences of partial gravity remain far less well understood. Until recently, no model had been able to replicate partial gravity such as that experienced on Mars (0.38 g), which would be critical to help sustain long-term missions and ensure a safe return to Earth. Recent development of two partial weight bearing (PWB) models, one in mice and one in rats, now allows for quadrupedal partial unloading that mimics Martian gravity. Resveratrol (RSV), a polyphenol most commonly found in grapes and blueberries, has been extensively investigated for its health benefits, including its anti-inflammatory, anti-oxidative, and anti-diabetic effects. In the context of mechanical unloading, RSV has also been shown to preserve bone and muscle mass. However, there is a lack of research regarding its effect on the musculoskeletal system in partial gravity. We hypothesized that a moderate daily dose of RSV (150 mg/kg/day) would help mitigate muscle deconditioning in a Mars gravity analog. Indeed, our results demonstrate that RSV treatment during partial unloading significantly preserves muscle function (e.g., the average change in grip force after 14 days of PWB40 was of −6.18, and +10.92% when RSV was administered) and mitigates muscle atrophy (e.g., RSV supplementation led to an increase of 21.6% in soleus weight for the unloaded animals). This work suggests the potential of a nutraceutical approach to reduce musculoskeletal deconditioning on a long-term mission to Mars.

Gravity analog model of non-equilibrium thermodynamics

Abstract The non-equilibrium thermodynamics of Onsager and Machlup and of Hashitsume is reformulated as a gravity analog model, in which thermodynamic variables, kinetic coefficients, and generalized forces form, respectively, coordinates and metric tensor and vector fields in a space of thermodynamic variables. The relevant symmetry of the model is the general coordinate transformation. Then, the entropy production is classified into three categories, when a closed path is depicted as a thermodynamic cycle. One category is time-reversal odd, and is attributed to the number of lines of magnetic flux passing through the closed path, having the monopole as a source. There are two time-reversal-even categories, one of which is attributed to the space curvature around the path, having the gravitational instanton as a source, which dominates for a rapid operation of the cycle. The last category is the usual one, which remains even for the quasi-equilibrium operation. It is possible to extend the model to include non-linear responses. In introducing new terms, dimensional counting is important, using two parameters, the temperature and the relaxation time. The effective action, being induced by the non-equilibrium thermodynamics, is derived. This is a candidate for the action that controls the dynamics of kinetic coefficients and thermodynamic forces. An example is given in a chemical oscillatory reaction in a solvent of van der Waals type. The fluctuation–dissipation theorem is examined à la Onsager, and a derivation of the gravity analog thermodynamic model from quantum mechanics is sketched, based on an analogy to the resonance problem.

Quantum analogue of a Kerr black hole and the Penrose effect in a Bose-Einstein condensate

Analog physics allows simulating inaccessible objects, such as black holes, in the lab. We propose to implement an acoustic Kerr black hole with quantized angular momentum in a polariton Bose-Einstein condensate. We show that the metric of the condensate is equivalent to the Kerr's one, exhibiting a horizon and an ergosphere. Using topological defects as test particles, we demonstrate an analog Penrose effect, extracting the rotation energy of the black hole. The particle trajectories are well described by the time-like geodesics of the Kerr metric, confirming the potential of analog gravity.

Electromagnetic analogue space-times, analytically and algebraically

While quantum field theory could more aptly be called the ‘quantum field framework’—as it encompasses a vast variety of varying concepts and theories—in comparison, relativity, both special and general, is more commonly portrayed as less of a ‘general framework’. Viewed from this perspective, the paradigm of analogue space-times (also often called analogue gravity) is to promote the specific theory of general relativity (Einstein gravity) to a framework which covers relativistic phenomena at large. Ultimately, this then also gives rise to new proposals for experiments in the laboratory, as it allows one to move general features of the ‘relativistic framework’ from general relativity to entirely new new areas of physics. This allows one to experimentally look into analogies of currently unobservable phenomena of general relativity proper. The only requirement for this to work is the presence of a notion of an upper limit for propagation speeds in this new setting. Systems of such a kind abound in physics, as all hyperbolic wave equations fulfil this requirement.Consequently, models for analogue space-times can be found aplenty. We shall demonstrate this here in two separate analogue space-time models, both taken from electrodynamics in continuous media. First of all, one can distinguish between analytic analogue models (where the analogue is based on some specific hyperbolic differential equation), on the one hand, and algebraic models (where the analogue is fashioned from the more or less explicit appearance of a metric tensor), on the other hand. Yet this distinction is more than just a matter of taste: the nature of the analogue space-time model will also determine which physical concepts from general relativity can be taken easily into an experimental context. Examples of this will constitute the main aim of this paper, and the Hawking effect in one of the two models considered the example of most immediate experimental interest.

A subcutaneous insulin pharmacokinetic model for insulin Detemir

Background and ObjectiveType 2 diabetes (T2D) is rapidly increasing in incidence and has significant social and economic costs. Given the increasing cost of complications, even relatively short delays in the onset of T2D can significantly reduce long-term complications and costs. Equally, recent studies have shown the onset of T2D can be delayed by use of long-acting insulin, despite the risk and concomitant low adherence. Thus, there is a strong potential motivation to develop models of long-acting insulin analogues to enable safe, effective use in model-based dosing systems. In particular, there are no current models of long-acting insulin Detemir and its unique action for model-based control. The objective of this work is to develop a first model of insulin Detemir and its unique action, and validate it against existing data in the literature. MethodsThis study develops a detailed compartment model for insulin Detemir. Model specific parameters are identified using data from a range of published clinical studies on the pharmacokinetic of insulin Detemir. Model validity and robustness are assessed by identifying the model for each study and using average identified parameters over several dose sizes and study cohorts. Comparisons to peak concentration, time of peak concentration and overall error versus measured plasma concentrations are used to assess model accuracy and validity. ResultsAlmost all studies and cohorts fit literature data to within one standard deviation of error, even when using averaged identified model parameters. However, there appears to be a noticeable dose dependent dynamic not included in this first model, nor reported in the literature studies. ConclusionsA first model of insulin Detemir including its unique albumin binding kinetics is derived and provisionally validated against clinical pharmacokinetic data. The pharmacokinetic curves are suitable for model-based control and general enough for use. While there are limitations in the studies used for validation that prevent a more complete understanding, the results provide an effective first model and justify the design and implementation of further, more precise human trials.

Climate change likely to reshape vegetation in North America's largest protected areas

AbstractClimate change poses a serious threat to biodiversity and unprecedented challenges to the preservation and protection of natural landscapes. We evaluated how climate change might affect vegetation in 22 of the largest and most iconic protected area (PA) complexes across North America. We use a climate analog model to estimate how dominant vegetation types might shift under mid‐ (2041–2070) and late‐century (2071–2100) climate according to the RCP 8.5 scenario. Maps depicting vegetation for each PA and time period are provided. Our analysis suggests that half (11 of 22) of the PAs may have substantially different vegetation by late‐21st century compared with reference period conditions. The overall trend is toward vegetation associated with warmer or drier climates (or both), with near complete losses of alpine communities at the highest elevations and high latitudes. At low elevation and latitudes, vegetation communities associated with novel climate conditions may assemble in PAs. These potential shifts, contractions, and expansions in vegetation portray the possible trends across landscapes that are of great concern for conservation, as such changes imply cascading ecological responses for associated flora and fauna. Overall, our findings highlight the challenges managers may face to maintain and preserve biodiversity in key PAs across North America.

Acoustic black holes in curved spacetime and the emergence of analogue Minkowski spacetime

Gravity is not only able to be mimicked in flat spacetimes, but also in curved spacetimes. We study analogue gravity models in curved spacetime by considering the relativistic Gross-Pitaevskii theory and Yang-Mills theory in the fixed background spacetime geometry. The results show that acoustic metrics can be emergent from curved spacetimes yielding a Hadamard product of a real metric-tensor and an analogue metric-tensor. Taking \emph{quantum vortices} as \emph{test particles}, we evaluate their released energy ratio during the "gravitational binding". The $2+1$-dimensional flat Minkowski metric is derived from the $3+1$-dimensional Anti-de Sitter space by considering perturbations of the Yang-Mills field, which implies that Minkowski spacetime can be also simulated and the derivations presented here have some deep connections with the holographic principle.

Economic benefits of blast-resistant biofortified wheat in Bangladesh: The case of BARI Gom 33

The first occurrence of wheat blast in 2016 threatened Bangladesh's already precarious food security situation. The Bangladesh Agricultural Research Institute (BARI), together with the International Maize and Wheat Improvement Center (CIMMYT) developed and released the wheat variety BARI Gom 33 that is resistant to wheat blast and other common diseases. The new variety provides a 5–8% yield gain over the available popular varieties, as well as being zinc enriched. This study examines the potential economic benefits of BARI Gom 33 in Bangladesh. First, applying a climate analogue model, this study identified that more than 55% of the total wheat-growing area in Bangladesh (across 45 districts) is vulnerable to wheat blast. Second, applying an ex-ante impact assessment framework, this study shows that with an assumed cumulative adoption starting from 2019–20 and increasing to 30% by 2027–28, the potential economic benefits of the newly developed wheat variety far exceeds its dissemination cost by 2029–30. Even if dissemination of the new wheat variety is limited to only the ten currently blast-affected districts, the yearly average net benefits could amount to USD 0.23–1.6 million. Based on the findings, international funder agencies are urged to support the national system in scaling out the new wheat variety and wheat research in general to ensure overall food security in Bangladesh and South Asia.