Academic literature on the topic 'Elevator Action'

This paper presents a new critical event detection method simplified for built into elevators. We first define that the critical event is unusual action such as violent action, counteraction, etc, and introduce the violent action level (VA level). We use an optical flow based method to analyze the current state of the motion through an ITV (Industrial TeleVision) camera. After motion analysis, we calculate a normalized statistical value, which is the VA level. The statistical value is the multiple of the optical flow direction variance, the optical flow magnitude variance, and optical flow area. Our method calculates the statistical value variance and normalize it by the variance. At last we can detect critical event by thresholding the VA level. Then we implement this method on a built-in device. The device has an A/D converter with special designed frame buffer, a 400 MIPS high-performance microprocessor, dynamic memory, and flash ROM. Since we need to process the method 4Hz or faster to keep the detection performance, we shrink the images into 80 by 60 pixels, introduce recursive correlation, and analyze optical flows. The specially designed frame buffer enables us to capture two sequential images at any time. After that we achieved a processing performance of 8Hz on it. Our method detects 80% of critical events where at a maximum false acception rate of 6%.

Introduction. An increase in crop production from the growing area of both vegetable root crops and all agricultural products results in grows of the load on the machine-technology complex when harvesting. The reason is that in the structure of machine-technological complexes there are not devices providing the qualitative screening of the heap incoming for processing. The purpose of the study is to identify the areas with the minimum value of soil screening on the rod elevator surface depending on the elevator apron angle and to develop recommendations and proposals for improving the separation quality. Materials and Methods. The article describes the methodology and results of laboratory studies of rod elevators with an asymmetric arrangement of web agitators and an adjustable elevator apron angle to determine the soil screening quality on its surface. We used the method of comprehensive assessment of the quality and stability of technological operations based on quantitative optimization criteria. Results. The highest value of the screened soil weight is at the wavelength attenuation section of the rod elevator working branch 1,020 mm cause by action of the elliptical web agitator at an elevation angle of 5 gon. Discussion and Conclusion. The rod elevator with asymmetric arrangement of web agitators and adjustable elevator apron angle increases the soil screening quality along the entire length of the elevator apron by 10 %, and therefore increases the completeness of separation of root crops from soil impurities.

This paper describes an elevator utility system that enables autonomous mobile robots to travel in office buildings. Attachments emulating the behavior of human fingers were developed to retrofit them to elevators without affecting elevators' inner workings. These attachments, consisting of button operation, controllers, and infrared ray communication, are remotely controlled by wireless commands from a robot. Mobile robots must use elevators without interfering with people using it, proposingcourses of robot action. A sensor system is presented for detecting people or objects in elevators. A prototype was developed, and its usefulness verified experimentally. The concept is expected to be useful for service robots working in office buildings.

The article explains the principle of operation of the new system of remote fi xation of grain movement (RFGM) in the silos of the elevator, created and tested in action at OOO (LLC) Ryazanelevator. The results of the work of a prototype of the RFGM system in the elevator silos are presented and the possibility of its use to control the release of grain from the elevator silos is shown.

AbstractQualitative models can be used for decision making under uncertainty. This provides a useful framework for evaluating the models. If the costs for every action/state of nature combination are known, decisions made using a well-calibrated model would result in actual costs being close to expected costs. In addition, the actual cost can be compared to the cost of perfect foresight actions, giving a bound on the value of a better model. Application of these procedures is made using a logit model developed to predict Missouri country grain elevator bankruptcies.

Introduction. Elevators in residential and public buildings are the means of vertical transport. An elevator is one of the complex electromechanical devices of increased danger. Therefore, all stages of its life cycle are strictly limited by regulatory documents. The desired levels of safety and comfort are provided through the reasonable choice of the basic parameters and a constant maintenance of the system in good condition. The key factors that affect the implementation of regulatory requirements during the operation of the elevator installation are the quality of manufacturing of critical components, the level of real workload, taking into account the actual value of the spent resource, and the implemented maintenance program. Currently, when determining the maintenance schedule for elevators, such characteristics as the density of occupancy, the level of power loads, the actual operating time of the elevator and the counts of starts of the main drive are not taken into account. This study objective is the scientific rationale of the concept and methodology for developing the program of maintenance of specific elevator installations on the basis of studies of the level and mode of loading of load-bearing units. Materials and Methods. The use of simulation modeling techniques to assess the load level of power units of an elevator installation and its kinematic indicators under the action of numerous random impacts is validated in the paper. The development of an indicator that characterizes the complex mode of elevator operation, taking into account the joint influence of the level of resource development, net operating time, number of starts, and the power load of the nodes, required the application of an expert method. The final part of the research program is the formation of specific recommendations on the maintenance schedule of elevators. It is based on the ranking of particular indicators. Results. The performance feature of the elevator installation is that the service time of a customer is a function of many random variables. Mathematical models of the formation of force impacts are based on the representation of an electromechanical elevator as a dynamic one-degree-of-freedom system. Expressions for calculating the static tension of traction ropes and torques on the motor shaft are obtained. The problem of dynamics is solved. The loads whose values are the basis for performing simulation modeling of the operating modes of the elevator installation are determined. Discussion and Conclusions. Feasibility of the regulations for the maintenance of passenger elevators is an urgent task, the solution to which determines the level of safety and comfort of passengers. Currently, the standards for the design and operation of elevator installations do not link the frequency of maintenance programs with the level of load and the amount of resource development. The paper provides a general statement of the problem and a methodology for the formation of a complex factor of the equivalent load. Mathematical models are given for calculating the power and temporary loads of the elevator, taking into account the nature of numerous random impacts.

Elevator muscle activity per unit bite-force has been shown to be higher in chewing than in isometric biting. We tested the hypothesis that surplus elevator activity is evoked in response to a possible co-activation of jaw-opener muscles during the masticatory power stroke. In 32 subjects, digastric and bilateral masseter and temporalis activities were recorded during unilateral chewing of test foods, isometric biting on a force transducer, and during balancing of the jaw against maximum effort of depressor muscles. During elevator peak effort in chewing, the digastric activity was 113% higher than during peak effort in isometric biting. Comparison of balancing and chewing trials revealed that a 6% increase of elevator activity would suffice to compensate for this increased depressor action. Elevator activity in chewing, however, was up to 130% higher than in clenching. We conclude that depressor counteraction could have only a minor influence on the generation of surplus muscle activity in chewing.

In order to generalize the applicability of nonlinear numerical investigation of the structural behavior of slab panels at high deflections, which utilizes tensile membrane action in the slabs, the meshing of such floor systems cannot be restricted to orthogonal grids. A separate but related issue is that nonlinear numerical modelling of internal slab panels with continuity across their edges has shown that the way in which their boundary conditions are defined can have a considerable influence on their predicted membrane forces in various situations. This research investigates the behaviour of the membrane forces in orthogonal and non-orthogonal composite slabs at elevated temperatures by means of numerical modelling. With different continuity conditions at slab panel edges, the effects of various boundary conditions on the tensile membrane action of non-orthogonal slabs at high deflections are identified. In order to achieve this end, a penalty function method is first developed which allows boundary conditions to be defined in terms of relationships between different degrees of freedom in the system’s global coordinates, as opposed to the conventional binary “free or restrained” choice for individual degrees of freedom. This allows boundary conditions either to be defined with respect to axes inclined to the global system, or to link displacements at different nodes. This easily defines suitable boundary conditions for non-orthogonal slabs, and also allows the continuity of internal panels to be realistically modelled. In terms of simplified design methods, it is often possible to divide internal floor areas of a building into rectangular or square panels, but the problem of slabs at or near the edges of non-orthogonal buildings still exists. This thesis attempts to begin to extend these methods to non-orthogonal slabs by determining the optimal small-deflection yield-line failure patterns for quadrilateral slabs of different geometries. Simplified design methods assume that the enhancement of capacity due to tensile membrane action increases continuously with vertical deflection. However, as slab deflection increases, through-depth cracks which may or may not coincide with the yield lines can occur, and these cause progressive reduction of the enhancement of load capacity. Optimizing assumed yield-line patterns by using a plastic work balance method, the research establishes and validates two existing yield-line patterns for trapezoidal slabs. Further studies to determine the precise yield-line patterns of trapezoidal slabs are made by gradually changing of the geometrical parameters. A new plastic energy method which includes the internal work dissipation during rebar extension has been extended to triangular slabs. The post-yield-line behaviour of such slabs has been demonstrated. This research validates and compares the enhancement factor performance from the new plastic energy method to the existing simplified design method. An investigation of the influence of different reinforcement meshes and geometry on the enhancement of load-carrying capacity of isosceles triangular slabs has been carried out.

This thesis investigates, using finite element modelling and experimental investigation, the fracture of mesh reinforcement in composite floor slabs at elevated temperatures. The main objective of the research is the study of the bond strength between the welded mesh reinforcement and concrete at elevated temperatures, since this was found to be the principal behaviour that governs the fracture of the reinforcement in a composite floor slab.The experimental programme included steady state and transient pull-out tests carried out at temperatures varying from 20°C to 1000°C. However, unlike previous work, which concentrated on the bond of single bars, rectangular normal concrete prisms were constructed with one longitudinal bar, ensuring a bond length of 200 mm, and one transverse bar welded centrally. As a result, the influence of the weld of the mesh reinforcement in the bond strength between reinforcement and concrete was studied. The bond strength-slip-temperature relationship was obtained for various sized ribbed and plain bars. It was found that the 6, 7 and 8mm diameter ribbed mesh failed by fracture of the longitudinal bar at all temperatures, including ambient temperature. It was shown that the reduction of bond strength of ribbed mesh was similar to the reduction in strength of the bar, which together with the observed modes of failure, lead to the conclusion that ribbed mesh can be assumed to be fully bonded at all temperatures. The 10mm diameter ribbed mesh failed by splitting due to the cover-bar diameter ratio being small. In contrast, all the plain bars failed by fracture of the weld followed by pull-out of the bar. Therefore the correct bond stress-slip relationship should be modelled for smooth bars to accurately predict global structural behaviour.The investigation using finite element modelling utilizes the DIANA program. The incorporation by the author of the bond strength-slip-temperature relationship within the models permits a better prediction of fracture of the reinforcement in composite floor slabs. It has been shown that smooth bars are more beneficial since the bond is broken before fracture of the bar allowing strains to be distributed along the bar. In the case of ribbed bars the bond is such that localised strain will occur in the bar at crack locations leading quickly to fracture of the reinforcement.

This thesis presents the results of a research programme to investigate the behaviour and robustness of reinforced concrete (RC) frames in fire. The research was carried out through numerical simulations using the commercial finite element analysis package TNO DIANA. The main focus of the project is the large deflection behaviour of restrained reinforced concrete beams, in particular the development of catenary action, because this behaviour is the most important factor that influences the frame response under accidental loading. This research includes four main parts as follows: (1) validation of the simulation model; (2) behaviour of axially and rotationally restrained RC beams at elevated temperatures; (3) derivation of an analytical method to estimate the key quantities of restrained RC beam behaviour at elevated temperatures; (4) response and robustness of RC frame structures with different extents of damage at elevated temperatures. The analytical method has been developed to estimate the following three quantities: when the axial compression force in the restrained beam reaches the maximum; when the RC beams reach bending limits (axial force = 0) and when the beams finally fail. To estimate the time to failure, which is initiated by the fracture of reinforcement steel at the catenary action stage, a regression equation is proposed to calculate the maximum deflections of RC beams, based on an analysis of the reinforcement steel strain distributions at failure for a large number of parametric study results. A comparison between the analytical and simulation results indicates that the analytical method gives reasonably good approximations to the numerical simulation results. Based on the frame simulation results, it has been found that if a member is completely removed from the structure, the structure is unlikely to be able to develop an alternative load carrying mechanism to ensure robustness of the structure. This problem is particularly severe when a corner column is removed. However, it is possible for frames with partially damaged columns to achieve the required robustness in fire, provided the columns still have sufficient resistance to allow the beams to develop some catenary action. This may be possible if the columns are designed as simply supported columns, but have some reserves of strength in the frame due to continuity. Merely increasing the reinforcement steel area or ductility (which is difficult to do) would not be sufficient. However, increasing the cover thickness of the reinforcement steel to slow down the temperature increase is necessary.

Abdominal Aortic Aneurysms (AAAs) are multi-genic, slow growing, degenerative vascular lesions resulting in focal aortic dilations. Following diagnosis, growth is monitored and the aneurysm surgically repaired when dilatation reaches 5.0 - 5.5 cm. Pharmacological treatments regressing or reducing growth rate remain a clinical ideal. Epidemiological evidence shows an inverse correlation between plasma High Density Lipoproteins (HDLs) and incidence of AAA, suggesting a role in the pathoaetiology This thesis investigates the role of HDLs in experimental AAA. Reconstituted HDL (rHDL - CSL-111) prevented AAA formation and reduced established AAA in mouse models. I used a hepatospecific adenoviral vector AdA-l; to induce production of human ApoA-l, increasing plasma HDL particles. Whilst infection with AdA-l significantly increased circulating human ApoA-l, it did not reduce established Ang Il-induced AAA or atheroma at the aortic root. Due to the complexity of HDL particles I elected to concentrate on mimicking its anti-inflammatory effects, rather than investigate alternate methods of increasing HDLs. One of HDL’s key anti-inflammatory effects is the prevention of Toll Like Receptor 4 (TLR4)-mediated inflammation, implicated in AAA development. I attempted to prevent AAA formation with a novel small molecule TLR4 antagonist, IAXO-102. IAXO-102 reduced TLR4-mediated aortic inflammation after three days of Ang II infusion; prevented AAA formation, and early rupture. Cytokines produced by TLR4-mediated inflammation stimulate other pro- inflammatory signalling pathways, such as the CD40/TRAF6 pathway. I investigated the effect of a CD40/TRAF6 inhibitor (687702), on experimental AAA. Following 3 days of Ang II infusion, treatment with Compound 6877002 made no significant difference to inflammatory markers associated with AAA; and no difference to vascular macrophage infiltration, a key cell mediator in AAA development. x HDLs are known to inhibit TLR4-mediated inflammation through up-regulation of Activating Transcription Factor 3 (ATF3), I investigated rHDLs manipulation of this negative feedback loop in HUVEC, and found stimulating HUVEC with rHDL, as well as with the TLR4 ligand LPS, induces ATF3 expression. Whilst surprisingly IAXO-102 did not prevent LPS stimulated ATF3 expression, 6877002 did, suggesting CD40/TRAF6 is essential for ATF3 expression. Through investigating the mechanisms in which HDL prevents AAA, I have highlighted the importance of TLR4 mediated inflammation in AAA and identified a potential pharmaceutical target.

O presente trabalho aborda o desenvolvimento de um algoritmo de controle para um sistema de suspensão ativa para elevadores de alto desempenho. Esses dispositivos são muito usados no caso de suspensões veículos automotivos, mas não tanto em elevadores. Visando compreender os fenômenos envolvidos e executar testes do controle proposto através de simulações, é realizado um estudo da modelagem matemática desse sistema. O elevador estudado é de cabine com duplo andar (double-deck) e será usado em uma guia de 200 [m] de curso em um edifício de aproximadamente 500 [m] de altura. A velocidade de estado estacionário do elevador é 40 km/h. Buscando situar este trabalho no campo de pesquisa proposto, é apresentada uma introdução aos critérios e técnicas de controle linear utilizadas. O desenvolvimento do controlador é baseado no uso de um modelo matemático linear em espaço de estados que representa a dinâmica do sistema em um dos planos ortogonais. A síntese do controlador por realimentação no espaço de estados foi feita usando o método da alocação de pólos, com ajuda do regulador quadrático linear, realimentando os estados com um observador de ordem total. Um modelo computacional foi construído e utilizado para a realização de simulações computacionais com o controlador proposto. Os resultados de simulações do sistema passivo e ativo são apresentados e discutidos.
The present work proposes the development of an algorithm to control active suspension systems for high performance elevators. These devices are used in suspensions for automotive vehicles, but not in such a way in elevators. Aiming at the understanding of the involved phenomena and making tests of the controller considered through simulations, a mathematical model of this system is developed. The studied elevator is a double-deck one and will be used in a 200 [m] guide in an approximately 500 [m] height skyscraper. The steady state speed of the elevator is 40 km/h. Trying to contextualize this work, it is presented an introduction to the criteria and techniques of linear control applied in this work. The development of the controller is based on the use of a linear mathematical model in the states space that represents the dynamics of the system in one of the two orthogonals planes. The synthesis of the feedback controller in the states space was made using the pole placement method with the aid of the linear quadratic regulator, and the feedback of the states with a full order observer. A computational model was constructed. The results of passive and active simulations of the system are presented and discussed.

Sutherlandia frutescens (tribe Galegeae, Fabaceae), is a popular medicinal plant traditionally used in South Africa. In 2000, a company called Phyto Nova (Pty) Ltd. initiated large-scale cultivation and contract manufacturing of tablets, made from the powdered herb (i.e. thin stems and leaves). Most of these commercial Sutherlandia solid dosage forms are made from the dried leaf powder but recently a new product, viz. Promune&trade
capsules, made from a freeze-dried aqueous extract, came on the market and was claimed to be &ldquo
better&rdquo
as it mimics the traditional tea. However, the pharmaceutical quality and stability of these preparations have not yet been investigated. The objectives of this study were firstly, to develop a validated stability-indicating HPLC assay for sutherlandioside B (SU-B)
secondly, to compare the SU-B levels in the two commercially available Sutherlandia products viz, the Phyto Nova Sutherlandia SU1&trade
tablet and the Promune&trade
capsule, and, thirdly, to determine the effect of elevated temperature and humidity as well as acid hydrolysis on the SU-B levels in these two products.

We examine the fraction of massive (M-* > 10(10)M(circle dot)) compact star-forming galaxies (cSFGs) that host an active galactic nucleus (AGN) at z similar to 2. These cSFGs are likely the direct progenitors of the compact quiescent galaxies observed at this epoch, which are the first population of passive galaxies to appear in large numbers in the early Universe. We identify cSFGs that host an AGN using a combination of Hubble WFC3 imaging and Chandra X-ray observations in four fields: the Chandra Deep Fields, the Extended Groth Strip, and the UKIDSS Ultra Deep Survey field. We find that 39.2(-3.6)(+3.9)% (65/166) of cSFGs at 1.4 < z < 3.0 host an X-ray detected AGN. This fraction is 3.2 times higher than the incidence of AGN in extended star-forming galaxies with similar masses at these redshifts. This difference is significant at the 6.2 sigma level. Our results are consistent with models in which cSFGs are formed through a dissipative contraction that triggers a compact starburst and concurrent growth of the central black hole. We also discuss our findings in the context of cosmological galaxy evolution simulations that require feedback energy to rapidly quench cSFGs. We show that the AGN fraction peaks precisely where energy injection is needed to reproduce the decline in the number density of cSFGs with redshift. Our results suggest that the first abundant population of massive quenched galaxies emerged directly following a phase of elevated supermassive black hole growth and further hints at a possible connection between AGN and the rapid quenching of star formation in these galaxies.

This thesis is about HELLP Syndrome (hemolysis, elevated liver enzymes, low platelet count in pregnancy): a devastating maternal hypertensive complication that results in multi-system changes that can rapidly deteriorate into organ failure and death. Despite rapid advancesin medical technology and medical science this disease continues to take 
the lives of women and their infants. The only effective intervention for this disorder is immediate termination irrespective of the gestational stage of the pregnancy. The primary objective of this thesis was to explore the subjective experiences and meaningmaking processes of women in and through their high-risk pregnancies. This objective crystallised into the following aims: to facilitate and listen to the voices of women who were HELLP Syndrome survivors
to explore the reported bodily, psychological and 
emotional experiences of HELLP Syndrome survivors
to understand the role medical intervention and biomedical discourses play in these women&rsquo
s experiences and finally to explore the subjective experiences of HELLP Syndrome in the context of traditionallyheld notions of motherhood. The study was couched in a feminist poststructuralist 
epistemology. A material-discursive framework which comprised phenomenological and poststructuralist theorising was usedin an attempt to understand both the lived experiences as well as the discursively constructed nature of those subjective experiences. Thus the analysis encompassed both a broadly phenomenological framework to understand the lived experiences of HELLP Syndrome, and a discourse analysis to explore the meaning-making processes of participants in relation to larger social 
discourses, in particular the dominant biomedical and motherhood discourses. A qualitative approach using in depth semi-structured interviews was utilisedto gather data. Eleven participants from very diverse backgrounds consented to be part of thisstudy. The findings of the study highlighted the immense trauma, difficulties and challenges participants faced in these high-risk situations. What was evident from the analysis was that their experiences were so diverse and werecompletely shaped by the severity of the disorder and the gestational stage of the pregnancy. Some women ended up in the Intensive Care Units (ICU) and had near-death experiences, some had very premature babies, while some of the participants lost their babies during the process. With regards to the emotional, psychological and corporeal aspects of the disorder,participants described their situations as a disaster, painful and difficult. Due to the rapid deterioration of symptoms, they described the tempo of these events as a whirlwind in which they felt they had no control. Emotions ranged from shock, total disbelief and surprise to anger, helplessness and powerlessness. Lacking knowledge and access to appropriate 
information further compounded the situation for participants. Theparticipants who had premature babies found the Neonatal Intensive Care Unit experience (NICU) extremely challenging and stressful. A discourse analysis revealed that women&rsquo
s talk was shaped by the disciplinary frameworks oftechnocratic medicine and patriarchal notions of 
gender. Participants&rsquo
discourses about their encounters inthe medical context werelocated in, and shaped by, the structure of health care in our country. In this regard binaries 
(like private versus public health care, women versus men and nurses versus doctors) were evident. Furthermore their hospital stay reflected their experiences in the Intensive 
Care (ICU) and the Neonatal Intensive Care Units (NICU) both of which are highly technologically orientated and managed. Biomedical discourses that filtered through the 
participants&rsquo
talk were: medicine as indisputable truth
mechanistic model of the body as machine
medical doctors as gods and the foetus as &lsquo
super subject&rsquo
. Discourses of risk 
were inevitably taken up as participants tried to make sense of both their current pregnancies and the potential ones to follow. The passage into motherhood for these 
participants was dependent on whether they had live babies or not. For those who had live babies it was a difficult time as they had to contend with their own recovery as well as the prematurity of their infants. The NICU experience was described as tiring, trying and cumbersome. For mothers who lost their babies it was a time of profound sadness and 
loss coupled to the notion that motherhood itself was lost. This loss of their children symbolised broken dreams, severed connections and a powerful taboo. In addition, discourses in which motherhood was naturalised and normalised saturated their talk and framed their experience in a narrative of deficit and failure. The ideologies of mother 
blame and the &lsquo
all responsible&rsquo
mother were pervasive in their discussions. In conclusion, this high-risk situation represented a time of tremendous uncertainty and unpredictability for all participants and was powerfully shaped by dominant discourses about motherhood and the biomedical discursive and institutional framework in which 
participants were subjugated. The study thus highlights how the HELLP syndrome experience illuminates the erasure of women&rsquo
s subjectivities while the foetus/infants&rsquo
life 
takes precedence. This has significant implications for scholarship in general and feminist scholarship in particular and highlights the need for this type of engagement in an area that has remained on the periphery of feminist research.

From the late Sixties on, industrial development in Italy evolved through the spread of small and medium sized firms, aggregated in district networks, with an elevated propensity to enterprise and the marked presence of owner-families. Installed within the local systems, the industrial districts tended to simulate large-scale industry exploiting lower costs generated by factors that were not only economic. The districts are characterised in terms of territorial location (above all the thriving areas of the North-east and Centre) and sector, since they are concentrated in the "4 As" (clothing-fashion, home-decor, agri-foodstuffs, automation-mechanics), with some overlapping with "Made in Italy". How can this model be assessed? This is the crucial question in the debate on the condition and prospects of the Italian productive system between the supporters of its capacity to adapt and the critics of economic dwarfism. A dispassionate judgement suggests that the prospects of "small is beautiful" have been superseded, but that the "declinist" view, that sees only the dangers of globalisation and the IT revolution for our SMEs is risky. The concept of irreversible crisis that prevails at present is limiting, both because it is not easy either to "invent", or to copy, a model of industrialisation, and because there is space for a strategic repositioning of the district enterprises. The book develops considerations in this direction, showing how an evolution of the district model is possible, focusing on: gains in productivity, scope economies (through diversification and expansion of the range of products), flexibility of organisation, capacity to meld tradition and innovation aiming at product quality, dimensional growth of the enterprises, new forms of financing, active presence on the international markets and valorisation of the resources of the territory. It is hence necessary to reactivate the behavioural functions of the entrepreneurs.

This chapter discusses the considerable research that has identified distinct functional circuits linking frontal cortex with the basal ganglia in the control of goal-directed and habitual actions. OCD is characterized by hyperactivity in a circuit involving some of these regions. Recent accounts of the interaction of goal-directed actions and habits suggest that these control processes interact hierarchically, so one alternative to current theories is that OCD reflects a dysfunction in this interactive process resulting in dysregulated action selection, whether that selection is driven by the outcome itself or by cues predicting the outcome. Importantly, it appears that both sources of action selection depend on the OFC—outcome based retrieval on the medial OFC and cue-related retrieval on the lateral OFC. From this perspective, therefore, hyperactivity of the OFC could produce both elevated outcome retrieval and increased responsiveness to outcomes-related cues, resulting in dysregulated action selection and compulsive action initiation as a consequence.

This chapter examines how FORCE members engaged in CRS’s style of insurgent prophetic redemption. FORCE leaders translated Alinsky-influenced community organizing principles, such as “power” and “self-interest,” and practices, such as “elevator speeches” and “one-on-ones,” in ways that resonated with members’ experiences on the street and in recovery. FORCE members, in turn, drew from recovery to reconstruct the meaning of community organizing; they drew from recovery’s ritual verbal displays, such as “check-ins” and “testimonies,” to turn monthly meetings and one-on-ones into settings that allowed them to give back and perform being reformed. Last, CRS organizers deprivatized members’ efforts at personal reform, such as personal testimonies, for collective and political action.

This chapter examines the expansion of volunteer participation in a participatory research project, which explored possibilities to enhance volunteer involvement in an academic camp operated by a non-governmental organization in the Dominican Republic. Although there are numerous studies that identify how organizations should involve volunteers, these studies typically represent an outsider perspective. Therefore, the concerns, ideas, and agency of volunteers—all of which may facilitate improvements in their participation—are often overlooked. For the purpose of this chapter, volunteers are elevated as key actors in the development of the organization. Specifically, community-based philosophy's concept of participation is applied to identify key moments in the project when the broadening of volunteer involvement was important for achieving a greater understanding of the issue of interest. The objective is to advance an appreciation of how projects with volunteer participation, albeit in fluctuating levels, can result in the co-creation and elevation of local knowledge.

In this physics/psychology related integrative project, gravitation acting on the elevator riders is discussed in psychological terms. It may be interesting to portray some characters and convey their emotional states and actions in this unusual situation. Science-based themes that serve as inspiration for this project refer to the physical concepts of gravitation as a natural force causing objects with mass to attract one another, acceleration due to gravity, and the potential energy of the stuck elevator. This project is also about an artistic interpretation of psychological and social aspects of the unusual and stressful circumstances.

Constantine’s son Constantius II particularly worked to encourage the emergence of a new, Christian Roman Empire by restricting pagan practices and transferring pagan temples to the ownership of the church. Christian authors like Firmicus Maternus framed actions like these as a form of progress that moved the empire closer to a better, Christian condition—a dramatic break from the traditional cycle of decline and renewal. Constantius also elevated the new city of Constantinople to parity with Rome, an action described to the Roman senate by his propagandist Themistius. The pagan emperor Julian, Constantius’s successor, set about undoing many of the steps Constantine and his sons had taken. Julian framed these actions as a restoration of Roman power and religious traditions, but, in some ways, his initiatives departed from past practices as well.

Glucose-induced oxidative stress can be found related to “glucose variability” and “glucose memory”. The irregular low and elevated glucose conditions cause damage to endothelial cell function than a steady, constant rise in level of glucose. Activation of PKC, NADPH oxidases, and mitochondrial oxidants are some of the pathways exhibited as a result of this aggravated cellular response. Regarding glucose memory, long after the normalization elevated level of glucose in the endothelial cells of diabetic rats and culture, a existance or ‘memory’ of induced basement membrane mRNA is expressed. This demonstrates that glucose causes dangerous long-term effects beyond the hyperglycemia period. Oxidative stress give rise to glucotoxicity and lipotoxicity which are phenomena’s related to diabetes. Following the pathogenesis of diabetes, hyperglycemia and hyperlipidemia exerts a supplementary toxic effect on the beta-cells. So, hyperglycemia can be considered as a requirement for the destructive effects of lipotoxicity. Thus glucolipotoxicity can be considered as a substitute for lipotoxicity which relates the detrimental correlation between lipids and beta-cell function. Generally, the antioxidant pharmacotherapy can be coupled with drugs to boost the natural cellular defense mechanisms as the naturally existing antioxidant components, which neutralizes free radical damage. This considers antioxidant a boon tool for pharmacotherapeutic agent.

In this work, a modeling and algorithm based on multiagent reinforcement learning is developed for the problem of elevator group dispatch. The main advantage is that, along with the function approximation, this multi-agent solution leads to reduction of the state space, allowing complex states to be addressed with a synthesizing evaluation function. Each elevator is considered an agent that have to decide about two actions: answer or ignore the new call. With some iterations, the agents learn the weights of an evaluation function which approximate the state-action value function. The performance of solution (average waiting time - AWT), shown varying the traffic pattern, flow of people, number of elevators and number of floors, is comparable to other current proposals reported in the literature.

Steel wires are critical load-bearing components in a wide range of applications such as elevator, cranes, mine haulage etc. The traction machine of elevator which transmits power to wire rope causes micro-slip between wire rope and sheave during reciprocating action. The lubrication condition of wire rope is also changed due to the lack of grease. This study focuses on the wear behavior of steel wire and effect of both dry and grease conditions by using the rolling/sliding contact wear tester done under various slip ratios and rolling speeds. The experimental results of the wear volume curve against the number of revolutions under the grease condition are compared with the results under dry condition. The worn surface of steel wire and the size of wear particles were observed by SEM. In order to quantify the wear amount of steel wire we established an equation and finally obtained the wear coefficient.

Elevator evacuation has been considered in high-rise building evacuation in the world, especially in China. Elevator safety has been widely studied for this purpose and technical standards are also available in different countries. However, it is critical to understand human behaviors in elevator evacuation before elevators can be used in building evacuation. It is expected that social relation (family, friend, classmate, etc.) will play an important role on evacuation behaviors. However, researches are largely missing on social relation and its impacts on movement and behaviors of the evacuees. This paper aims to investigate the crowd evacuation considering social relation. An evacuation experiment is conducted in a 11-storey office building. Participants who take part in the experiment include individuals, families and lovers. Evacuation behaviors especially decision-making as well as important factors affecting evacuees’ choices are discussed. Movement characteristics of evacuees in the stair are also analyzed. It is concluded that family members will take actions, such as take elevators or stairs, together. Females and evacuees in poor condition prefer to take the elevator during evacuation. Many pairs or small groups may be formed owing to social relations. The groups take more time to make decision. The members in small groups may block the traffic and slow down the speed of the crowd. Evacuation efficiency changes greatly considering small group behaviors and social relations. Experimental results are helpful for determining the effective rules and regulations in elevator evacuation in high-rise buildings.

Numerous approaches with single and multiple drugs modulating protease cascade, platelet function and blood viscosity and to reduce blood lipids to manage thrombotic processes have been tried. Defibrotide, a polydeoxyribonucleotide, (Mr =17,000) offers a new approach to vascular and related thrombotic processes as it acts via modulation of endothelial cell function. We have used a primate model (Macaca mulatta) to study the endogenous action of this agent after the oral (10-25 mg/kg) and intravenous (5-10 mg/kg) administration. This agent produced no effect on clotting tests and ex vivo laboratory findings but rather it elevated the t-PA (antigen and functional), protein C (antigen and functional), prostacyclin and decreased thromboxane, 01.2-antiplasmin (functional) and t-PA inhibitor (functional) in both studies. These observations suggest that Defibrotide modulates endothelial function. Hepatic isolation in rabbits totally blocked the antithrombotic actions of Defibrotide suggesting that this agent is converted into an active product endogenously. Pretreatment of Defibrotide with nucleases also resulted in a complete loss of its actions. Defibrotide produced dose dependent antithrombotic actions in animal models (rabbit venous stasis and rat vena caval ligation) after either intravenous or oral administration. Blood pressure, heart rate, respiration and kidney function were not altered by it. No effect on bleeding time was noted in any studies. Upon oral administration this drug produced pharmacologic action after 2 hours whereas after intravenous administration, the action peaked at 30 minutes. Defibrotide exhibited cytoprotective effects towards endothelial lining of the vascular smooth muscles characterized by microscopic studies. In summary Defibrotide is an endothelial support agent whose multicomponent actions are primarily mediated via the physical and functional modulation of the endothelial cells in the vascular system.

Platelet function is inhibited by agents that elevate intracellular cyclic AMP concentrations, presumably as a result of the cyclic AMP-stimulated phosphorylation of intracellular proteins. Polypeptides that become phosphorylated are of Mr = 250,000, Mr = 51.000 (P51), Mr = 36,000 (P36), Mr = 24,000 (P24), and Mr = 22.000 (P22). The Mr = 250,000 polypeptide is actin-binding protein, but the identity of the other polypeptides 1s unknown. In the present study, we identified the P24 polypeptide. Platelets were radiolabeled with [32P]P1 and then Incubated for 2-5 min in the presence or absence of 5 μM prostaglandin E1 (PGE1). The PGE1-induced phosphorylation of P24 was detected on autoradiograms of SDS-gels. Since P24 has been shown to be membrane-associated, its molecular weight was compared with those of known membrane proteins. P24 comigrated with the β-chain of purified GP Ib on reduced gels (Mr = 24,000) and also on nonreduced gels (when GP Ibβ is disulfide-linked to GP Ibα and migrates with Mr = 170,000). Like GP Ibβ, P24 was associated with actin filaments in Triton X-100 lysates. Both GP Ibβ and P24 were selectively associated with filaments of the membrane skeleton and were released from filaments when the Ca2+-dependent protease was active. Antibodies against GP Ib immunoprecipitated P24 from platelet lysates. Finally, exposure of Bernard-Soulier platelets (that lacked GP Ib) to PGE1 resulted in phosphorylation of actin-binding protein, P51, P36, and P22, but not P24. We conclude that P24 is GP Ibβ. To determine whether phosphorylation of GP Ibβ is responsible for the inhibitory effects of PGE1 on platelets, we compared the action of PGE1 on control platelets with that on Bernard-Soulier platelets. One of the ways in which PGE1 inhibits platelet activation is by inhibiting the polymerization of actin. While PGE1 inhibited actin polymerization in control platelets, it did not in Bernard-Soulier platelets. We conclude that GP Ibβ is phosphorylated by agents that elevate cyclic AMP and that phosphorylation of this glycoprotein results in inhibition of platelet function.

In this paper, the integrated structure/controller optimization has been applied to design the active damping guide roller to suppress the elevator lateral vibration. The guide rollers and their corresponding controller are considered as the design variables, simultaneously. And the weighted sum of the suspension deflection, the elevator’s acceleration and the control force are regarded as optimization functions to be minimized. Because a structured controller is used, this optimization problem can be solved by Genetic Algorithm directly. The control scheme is validated for a scaled elevator in the lab. The numerical results show that the integrated structure/controller design can provide an alternative method to achieve better ride comfort with a “sky-hook” damper controller compared to the sequential design.

Abstract A fatal accident occurred when a right angle gear box on an auger elevator disintegrated freeing the outboard end of a rotating PTO shaft. The tractor, acting as a stationary power source, flailed the PTO shaft which then struck and killed a farmer. No similar occurrences have been reported for the nearly 2000 similar units which have been used for over a decade. This paper studies a number of fundamental failure modes in order to determine which failure modes created the accident. Systematic analysis showed that the accident was caused by unusual misuse of the product. Known safety control concepts do not preclude this unforeseeable event.

The majority of sexually active girls aged 15–19 in developing countries are married, and married adolescent girls tend to have higher rates of HIV infection than their sexually active, unmarried peers. Married adolescent girls represent a sizable fraction of adolescents at risk and experience some of the highest rates of HIV prevalence of any group. Nonetheless, married adolescents have been marginal in adolescent HIV/AIDS policies and programs and have not been the central subjects for programs aimed at adult married women. This paper offers a partial explanation for why married adolescents have so often been overlooked, the reasons why marriage might bring elevated risk of HIV, initial analytic tools to assist policymakers in determining how to accord appropriate levels of priority to the marriage process, five brief case studies, and a menu of potential policy interventions and actions to make married adolescents an integral part of reproductive health and HIV-prevention initiatives.

To promote active transportation modes (such as bike ride and walking), and to create safer communities for easier access to transit, it is essential to provide consolidated data-driven transportation information to the public. The relevant and timely information from data facilitates the improvement of decision-making processes for the establishment of public policy and urban planning for sustainable growth, and for promoting public health in the region. For the characterization of the spatial variation of transportation-emitted air pollution in the Fresno/Clovis neighborhood in California, various species of particulate matters emitted from traffic sources were measured using real-time monitors and GPS loggers at over 100 neighborhood walking routes within 58 census tracts from the previous research, Children’s Health to Air Pollution Study - San Joaquin Valley (CHAPS-SJV). Roadside air pollution data show that PM2.5, black carbon, and PAHs were significantly elevated in the neighborhood walking air samples compared to indoor air or the ambient monitoring station in the Central Fresno area due to the immediate source proximity. The simultaneous parallel measurements in two neighborhoods which are distinctively different areas (High diesel High poverty vs. Low diesel Low poverty) showed that the higher pollution levels were observed when more frequent vehicular activities were occurring around the neighborhoods. Elevated PM2.5 concentrations near the roadways were evident with a high volume of traffic and in regions with more unpaved areas. Neighborhood walking air samples were influenced by immediate roadway traffic conditions, such as encounters with diesel trucks, approaching in close proximity to freeways and/or busy roadways, passing cigarette smokers, and gardening activity. The elevated black carbon concentrations occur near the highway corridors and regions with high diesel traffic and high industry. This project provides consolidated data-driven transportation information to the public including: 1. Transportation-related particle pollution data 2. Spatial analyses of geocoded vehicle emissions 3. Neighborhood characterization for the built environment such as cities, buildings, roads, parks, walkways, etc.

1.1 Resumen macroeconómico En el segundo trimestre la economía enfrentó varios choques, principalmente de oferta y de costos, la mayoría de los cuales no fueron anticipados, o los previstos fueron más persistentes de lo esperado, y que en conjunto interrumpieron la recuperación de la actividad económica observada a comienzos de año y llevaron la inflación total a niveles superiores a la meta. La inflación básica (sin alimentos ni regulados: SAR) aumentó, pero se mantuvo baja y acorde con lo esperado por el equipo técnico. A comienzos de abril se inició una tercera ola de pandemia, más acentuada y prolongada que la anterior, con un elevado costo en vidas humanas y algún impacto negativo en la recuperación económica. Entre mayo y mediados de junio los bloqueos de las carreteras y los problemas de orden público tuvieron un fuerte efecto negativo sobre la actividad económica y la inflación. Se estima que la magnitud de estos dos choques combinados habría generado una caída en niveles en el producto interno bruto (PIB) con respecto al primer trimestre del año. Adicionalmente, los bloqueos causaron un aumento significativo de los precios de los alimentos. A estos choques se sumaron los efectos acumulados de la disrupción global en algunas cadenas de valor y el incremento en los fletes internacionales que desde finales de 2020 vienen generando restricciones de oferta y aumentos de costos. Todos estos factores, que afectaron principalmente el índice de precios al consumidor (IPC) de bienes y de alimentos, explicaron la mayor parte del error de pronóstico del equipo técnico y el aumento de la inflación total a niveles superiores a la meta del 3 %. El incremento en la inflación básica y de los precios de los regulados fue acorde con lo esperado por el equipo técnico, y se explica principalmente por la eliminación de varios alivios de precios otorgados un año atrás. A todo esto se suma la mayor percepción de riesgo soberano y las presiones al alza que esto implica sobre el costo de financiamiento externo y la tasa de cambio. A pesar de los fuertes choques negativos, el crecimiento económico esperado para la primera mitad del año (9,1%), es significativamente mayor que lo proyectado en el informe de abril (7,1%), signo de una economía más dinámica que se recuperaría más rápido de lo previsto. Desde finales de 2020 las diferentes cifras de actividad económica han mostrado un crecimiento mayor que el esperado. Esto sugiere que los efectos negativos sobre el producto de las recurrentes olas de contagio estarían siendo cada vez menos fuertes y duraderos. No obstante, la tercera ola de contagio del Covid-19, y en mayor medida los bloqueos a las vías y los problemas de orden público, habrían generado una caída del PIB durante el segundo trimestre, frente al primero. Pese a lo anterior, los datos del índice de seguimiento a la economía (ISE) de abril y mayo han resultado mayores que lo esperado, y las nuevas cifras de actividad económica sectoriales sugieren que el impacto negativo de la pandemia sobre el producto se sigue moderando, en un entorno de menores restricciones a la movilidad y de mayor avance en el ritmo de vacunación. Los registros de transporte de carga (junio) y la demanda de energía no regulada (julio), entre otros, indican una recuperación importante después de los bloqueos en mayo. Con todo lo anterior, el incremento anual del PIB del segundo trimestre se habría situado alrededor del 17,3 % (antes 15,8 %), explicado en gran parte por una base baja de comparación. Para todo 2021 el equipo técnico incrementó su proyección de crecimiento desde un 6 % hasta el 7,5 %. Este pronóstico, que está rodeado de una incertidumbre inusualmente elevada, supone que no se presentarán problemas de orden público y que posibles nuevas olas de contagio del Covid-19 no tendrán efectos negativos adicionales sobre la actividad económica. Frente al pronóstico del informe pasado, la recuperación de la demanda externa, los niveles de precios de algunos bienes básicos que exporta el país y la dinámica de las remesas de trabajadores han sido mejores que las esperadas y seguirían impulsando la recuperación del ingreso nacional en lo que resta del año. A esto se sumaría la aún amplia liquidez internacional, la aceleración en el proceso de vacunación y las bajas tasas de interés, factores que continuarían favoreciendo la actividad económica. La mejor dinámica del primer semestre, que llevó a una revisión al alza en el crecimiento de todos los componentes del gasto, continuaría hacia adelante y, antes de lo esperado en abril, la economía recuperaría los niveles de producción de 2019 a finales de 2021. El pronóstico continúa incluyendo efectos de corto plazo sobre la demanda agregada de una reforma tributaria de magnitud similar a la proyectada por el Gobierno. Con todo eso, en el escenario central de este informe, el pronóstico de crecimiento para 2021 es del 7,5 % y para 2022 del 3,1 %. A pesar de esto, el nivel de la actividad económica seguiría siendo inferior a su potencial. La mejora en estas proyecciones, sin embargo, está rodeada de una alta incertidumbre. En junio la inflación anual (3,63 %) aumentó más de lo esperado debido al comportamiento del grupo de alimentos, mientras que la inflación básica (1,87 %) fue similar a la proyectada. En lo que resta del año el mayor nivel del IPC de alimentos persistiría y contribuiría a mantener la inflación por encima de la meta. A finales de 2022 la inflación total y básica retornarían a tasas cercanas al 3 %, en un entorno de desaceleración del IPC de alimentos y de menores excesos de capacidad productiva. En los meses recientes el aumento en los precios internacionales de los fletes y de los bienes agrícolas, y las mayores exportaciones de carne y el ciclo ganadero han ejercido presiones al alza sobre el precio de los alimentos, principalmente de los procesados. A estas fuerzas persistentes se sumaron los bloqueos de las vías nacionales y los problemas de orden público en varias ciudades registrados en mayo y parte de junio, los cuales se reflejaron en una fuerte restricción en la oferta y en un aumento anual no esperado del IPC de alimentos (8,52 %). El grupo de regulados (5,93 %) también se aceleró, debido a la baja base de comparación en los precios de la gasolina y a la disolución de parte de los alivios a las tarifas de servicios públicos otorgados en 2020. Como se proyectaba, la inflación SAR repuntó al 1,87 %, debido a la reactivación de los impuestos indirectos de algunos bienes y servicios eliminados un año atrás, y por las presiones al alza que ejercieron los alimentos sobre las comidas fuera del hogar (CFH), entre otros. En lo que resta del año se espera que el aumento en los alimentos perecederos se revierta, siempre y cuando no se registren nuevos bloqueos duraderos a las vías nacionales. El mayor nivel de precios de los alimentos procesados persistiría y contribuiría a mantener la inflación por encima de la meta a finales de año. La inflación SAR continuaría con una tendencia creciente, en la medida en que los excesos de capacidad productiva se sigan cerrando y registraría un aumento transitorio en marzo de 2022, debido principalmente al restablecimiento del impuesto al consumo en las CFH. Con todo esto, para finales de 2021 y 2022 se estima una inflación total del 4,1 % y 3,1 %, y una inflación básica del 2,6 % y 3,2 %, respectivamente. El comportamiento conjunto de los precios del IPC SAR, junto con continuas sorpresas al alza en la actividad económica, son interpretados por el equipo técnico como señales de amplios excesos de capacidad productiva de la economía. Estos persistirían en los siguientes dos años, al final de los cuales la brecha del producto se cerraría. El mayor crecimiento económico sugiere una brecha del producto menos negativa que la estimada hace un trimestre. Sin embargo, el comportamiento de la inflación básica, especialmente en servicios, indica que el PIB potencial se ha recuperado de forma sorpresiva y que los excesos de capacidad siguen siendo amplios, con una demanda agregada afectada de forma persistente. Esta interpretación encuentra soporte en el mercado laboral, en donde persiste un desempleo alto y la recuperación de los empleos perdidos se estancó. Adicionalmente, los aumentos en la inflación en buena medida están explicados por choques de oferta y de costos y por la disolución de algunos alivios de precios otorgados un año atrás. Los pronósticos de crecimiento y de inflación descritos son coherentes con una brecha del producto que se cierra más rápido y es menos negativa en todo el horizonte de pronóstico con respecto al informe de abril. No obstante, la incertidumbre sobre los excesos de capacidad es muy alta y es un riesgo sobre el pronóstico. Las perspectivas de las cuentas fiscales de Colombia se deterioraron, Standard & Poor’s Global Ratings (S&P) y Fitch Ratings (Fitch) redujeron su calificación crediticia, los bloqueos y problemas de orden público afectaron el producto y el país enfrentó una nueva ola de contagios de Covid-19 más acentuada y prolongada que las pasadas. Todo lo anterior se ha reflejado en un aumento de las primas de riesgo y en una depreciación del peso frente al dólar. Esto ha ocurrido en un entorno favorable de ingresos externos. Los precios internacionales del petróleo, del café y de otros bienes básicos que exporta el país aumentaron y han contribuido a la recuperación de los términos de intercambio y del ingreso nacional, y han mitigado las presiones al alza sobre las primas de riesgo y la tasa de cambio. En el presente informe se incrementó el precio esperado del petróleo para 2021 a USD 68 por barril (antes USD 61 bl) y para 2022 a USD 66 bl (antes USD 60 bl). Esta mayor senda presenta una convergencia hacia precios menores que los observados recientemente, como resultado de una mayor oferta mundial esperada de petróleo, la cual más que compensaría el incremento en la demanda de este bien básico. Por ende, se supone que el aumento reciente de los precios tiene un carácter transitorio. En el escenario macroeconómico actual se espera que las condiciones financieras internacionales sean algo menos favorables, a pesar de la mejora en los ingresos externos por cuenta de una mayor demanda y unos precios del petróleo y de otros productos de exportación más altos. Frente al informe de abril el crecimiento de la demanda externa fue mejor que el esperado, y las proyecciones para 2021 y 2022 aumentaron del 5,2 % al 6,0 % y del 3,4 % al 3,5 %, respectivamente. En lo corrido del año las cifras de actividad económica muestran una demanda externa más dinámica de la esperada. En los Estados Unidos y China la recuperación del producto ha sido más rápida que la registrada en los países de la región. En estos últimos la reactivación económica ha estado limitada por los rebrotes del Covid-19, las limitaciones en la oferta de vacunas y el poco espacio fiscal para enfrentar la pandemia, entre otros factores. La buena dinámica en el comercio externo de bienes se ha dado en un entorno de deterioro en las cadenas de valor y de un aumento importante en los precios de las materias primas y en el costo de los fletes. En los Estados Unidos la inflación sorprendió al alza y su valor observado y esperado se mantiene por encima de la meta, al tiempo que se incrementó la proyección de crecimiento económico. Con esto, el inicio de la normalización de la política monetaria en ese país se daría antes de lo proyectado. En este informe se estima que el primer incremento en la tasa de interés de la Reserva Federal de los Estados Unidos se dé a finales de 2022 (antes del primer trimestre de 2023). Para Colombia se supone una mayor prima de riesgo frente al informe de abril y se sigue esperando que presente una tendencia creciente, dada la acumulación de deuda pública y externa del país. Todo esto contribuiría a un incremento en el costo del financiamiento externo en el horizonte de pronóstico. La postura expansiva de la política monetaria sigue soportando unas condiciones financieras internas favorables. En el segundo trimestre la tasa de interés interbancaria y el índice bancario de referencia (IBR) se han mantenido acordes con la tasa de interés de política. Las tasas de interés promedio de captación y crédito continuaron históricamente bajas, a pesar de algunos incrementos observados a finales de junio. La cartera en moneda nacional detuvo su desaceleración anual y, entre marzo y junio, el crédito a los hogares se aceleró, principalmente para compra de vivienda. La recuperación de la cartera comercial y de los desembolsos a ese sector fue importante, y se alcanzó de nuevo el elevado saldo observado un año atrás, cuando las empresas requirieron niveles significativos de liquidez para enfrentar los efectos económicos de la pandemia. El riesgo de crédito aumentó, las provisiones se mantienes altas y algunos bancos han retirado de su balance una parte de su cartera vencida. No obstante, las utilidades del sistema financiero se han recuperado y sus niveles de liquidez y solvencia se mantienen por encima del mínimo regulatorio. A partir de este informe se implementará una nueva metodología para cuantificar y comunicar la incertidumbre que rodea los pronósticos del escenario macroeconómico central, en un entorno de política monetaria activa. Esta metodología se conoce como densidades predictivas (DP) y se explica en detalle en el Recuadro 1. Partiendo del balance de riesgos que contiene los principales factores que, de acuerdo con el juicio del equipo técnico, podrían afectar a la economía en el horizonte de pronóstico, la metodología DP produce distribuciones de probabilidad sobre el pronóstico de las principales variables (v. g.: crecimiento, inflación). Estas distribuciones reflejan el resultado de los posibles choques (a variables externas, precios y actividad económica) que podría recibir la economía y su transmisión, considerando la estructura económica y la respuesta de política monetaria en el futuro. En este sentido, permiten cuantificar la incertidumbre alrededor del pronóstico y su sesgo. El ejercicio DP muestra un sesgo a la baja en el crecimiento económico y en la brecha del producto, y al alza en la inflación. El balance de riesgos indica que las disyuntivas para la política monetaria serán potencialmente más complejas que lo contemplado en el pasado. Por el lado de las condiciones de financiamiento externo, se considera que el mayor riesgo es que se tornen un poco menos favorables, en un escenario en el cual la Reserva Federal de los Estados Unidos incremente con mayor prontitud su tasa de interés. Esto último, ante un crecimiento económico y del empleo mayor que el esperado en los Estados Unidos que genere presiones significativas sobre la inflación de ese país. A esto se suma la incertidumbre sobre el panorama fiscal en Colombia y sus efectos sobre la prima de riesgo y el costo del financiamiento externo. En el caso del crecimiento, la mayoría de los riesgos son a la baja, destacándose los efectos de la incertidumbre política y fiscal sobre las decisiones de consumo e inversión, la aparición de nuevas olas de contagio de la pandemia del Covid-19 y sus impactos sobre la actividad económica. En el caso de la inflación, se incorporó el riesgo de una mayor persistencia de los choques asociados con la disrupción de las cadenas de valor, mayores precios internacionales de las materias primas y de los alimentos, y una recuperación más lenta que la esperada de la cadena agrícola nacional afectada por los pasados bloqueos a las vías. Estos riesgos presionarían al alza principalmente los precios de los alimentos y de los bienes. Como principal riesgo a la baja se incluyó un alza de los arriendos menor que el esperado en el escenario central, explicada por una demanda débil y por una mayor oferta en 2022 dadas las altas ventas de vivienda observadas en el presente año. Con todo, el crecimiento económico presenta un sesgo a la baja y, con el 90 % de confianza, se encontraría entre un 6,1 % y 9,1 % para 2021 y entre el 0,5 % y 4,1 % para 2022. La brecha del producto tendría un sesgo a la baja, principalmente en 2022. El sesgo de la inflación es al alza, y se encontraría entre el 3,7 % y 4,9 % en 2021, y el 2,2 % y 4,7 % en 2022, con un 90 % de probabilidad. 1.2 Decisión de política monetaria En las reuniones de junio y julio la JDBR decidió mantener la tasa de política monetaria inalterada en 1,75 %.