Japans mid-nineteenth century opening-up to Western influence, the so-called Meiji Restoration, drove political leaders to form a politically modern centralized country. Although Japan experienced a number of major decentralization processes under the post World War II Allied occupation, the Japanese government reviewed these reforms after the occupation. In fact during the post WWII era, the centralized system played a major role in establishing a national minimum standard of living. While political trends in the 1990s favored government decentralization, promotion of decentralization became a challenge for successive Cabinets. In 1999, the Diet enacted the Package Promoting Decentralization Act; this law repealed the delegation system under which local governments are subordinate to the central government. In 2003, the Koizumi Administration created the Trinity Reform plan. Trinity means the decentralization reform process that involves three factors : 1) A local allocation tax grant; 2) A national subsidy for local governments, and 3) A local tax. The package included reducing national subsidies to local governments and transferring tax revenue sources from the central government to local governments. Both Japans central government and local governments are financially closely connected and both face severe fiscal conditions. Japan has an aging population and the coming increase of social security related expenditures is a huge fiscal challenge. It is financially questionable whether the central government can continue to provide the local allocation tax grants which guarantee financial resources to cover revenue shortfalls of local governments. The central and local governments have to review their budgets with a concerted effort to improve government efficiency. The theorem on fiscal federalism argues that local governments can provide public services more efficiently and be more responsible to their residents through competition among local governments. However, decentralization in Japan contains two fundamental challenges : heavy duplication of roles and ambiguous fiscal responsibility across levels of government. What is necessary for decentralization in Japan is to narrow the role of the central governments. Furthermore, the central government revenue guarantee function should be limited; it is imperative to establish hard budget constraints at the local government level. The author would like to emphasize decentralization should be compatible with reconstruction of the public finance system. In the first chapter, the author explores the historical background of the relationship between Japans central government and local governments. Then, in the second chapter, the author introduces the recent Japanese government promotion of decentralization. Thereafter, the author provides an overview of financial relationships across levels of government in the third chapter. In the fourth chapter, the author surveys economic theories on fiscal federalism, whereby the author would like to clarify the advantages of decentralization. Then, in the fifth chapter, the author summarizes the two fundamental challenges between the central and local government in Japan : duplication of roles and ambiguous expenditure responsibility. Finally, the author makes suggestions for promoting Japanese government decentralization mainly focusing on the use of fiscal instruments.
The purpose of this paper is to give four new applications of the Quillen-Suslin theorem to mathematical systems theory. Using a constructive version of the Quillen-Suslin theorem, also known as Serre's conjecture, we show how to effectively compute flat outputs and injective parametrizations of flat multidimensional linear systems. We prove that a flat multidimensional linear system is algebraically equivalent to the controllable 1-D dimensional linear systems obtained by setting all but one functional operator to zero in the polynomial matrix defining the system. In particular, we show that a flat ordinary differential time-delay linear system is algebraically equivalent to the corresponding ordinary differential system without delay, i.e., the controllable ordinary differential linear system obtained by setting all the delay amplitudes to zero. We also give a constructive proof of a generalization of Serre's conjecture known as Lin-Bose's conjecture. Moreover, we show how to constructively compute (weakly) left-/right-/doubly coprime factorizations of rational transfer matrices over a commutative polynomial ring. The Quillen-Suslin theorem also plays a central part in the so-called decomposition problem of linear functional systems studied in the literature of symbolic computation. In particular, we show how the basis computation of certain free modules, coming from projectors of the endomorphism ring of the module associated with the system, allows us to obtain unimodular matrices which transform the system matrix into an equivalent block-triangular or a block-diagonal form. Finally, we demonstrate the package QuillenSuslin which, to our knowledge, contains the first implementation of the Quillen-Suslin theorem in a computer algebra system as well as the different algorithms developed in the paper.
Open access
Advanced Differential Equations and Dynamical Systems
Most modern countries, whether they are unitary or federal, have several levels of territorial government as one of the imperatives of the modern organization of the state, operating in order to meet the most disparate needs encountered at lower levels of government.Different countries have different levels of government, and each of them a different hierarchy of public administration bodies where citizens decide on the offer of public services and their financing through elections.While the role of the central level of government is today in the creation of a national infrastructure and development of a better qualified workforce in order to make the state competitive internationally, the importance of the local government is before all in the creation of the entrepreneurial infrastructure, transport and communications.Therefore, it becomes clear that lower levels of government have an increasingly important role in the development of the country so that a growing number of countries worldwide are implementing reforms in the area of fiscal decentralization.Nevertheless, although desirable, fiscal decentralization is not an easy task for any state.There are numerous problems and obstacles in that process, which influence the decision on decentralization, fiscal smoothing and the issue of state intervention.
Paul Keel, Patrick Henry Winston, William L. Porter
Abstract : Our work focused on conceiving and prototyping technologies for supporting individual and collaborative sense-making activities in distributed and decentralized work environments. We developed an experimental computational environment referred to as the EWall system. The EWall system is designed to be used for users to conduct, for researchers to investigate, and for computational systems to support individual and collaborative sense-making activities. The EWall system engages users in the visual organization of information through the spatial arrangement and modification of graphical objects. Computational agents infer from spatial information arrangements and the collaborative use of information as a basis for directing the flow of information among collaborating users and computational systems. The goal of the agents is to direct the distribution of information in ways that bring together people with complimentary backgrounds, expertise, interests and objectives and that improves team shared understanding. Individual agents represent unique cognitive and collaborative concepts, combine their analyses, and autonomously adapt to particular users, tasks and circumstances. The primary contribution of this work lies in the design of concepts and mechanics that enable a noninterruptive interchange of contextual discoveries between humans and computational systems.
Introduction In 1981, the Reagan administration in the US, the Thatcher administration in the UK, and their allies compelled the International Monetary Fund (IMF) and World Bank Group (known as the “International Financial Institutions” [IFIs]) to launch an ideological assault against the state and promote a shift in power from the state to the market. From 1981 to the present, the IFIs have financed structural adjustment agreements (SAAs) in developing and transition countries to achieve that goal. Structural adjustment agreements call upon recipient governments to liberalize and privatize economies in the context of strict budget discipline. Adjustment lending facilitates economic integration – the hallmark of globalization – on terms that are advantageous to corporate and finance capital. The policy conditions associated with adjustment loans have accelerated transnational corporate penetration and expansion of markets in developing countries and lowered risks of portfolio investment and foreign direct investment. The role of the state has been reshaped to serve market liberalization, as governments have downsized, decentralized, and privatized (or “contracted out”) their functions. Such measures were intended to jump-start economic growth and free up resources for debt service. However, in most countries, public investment in critical areas (health care, education, infrastructure) foundered, growth rates were disappointing, and debts mounted to unsustainable levels (Pettifor 2001). This volume explores the relationship between adjustment and respect for human rights. Importantly, as governments in developing countries implemented World Bank and IMF-financed structural adjustment programs (SAPs), respect for human rights diminished.
According to Byron Kennard , Executive Director of the Center for Small Business and the Environment , the Industrial Age was concerned with large scale, highly centralized production which often damaged the environment (e.g., steel production). 1 On the other hand the Post-Industrial Age is concerned with decentralized technology and distributed production which are cleaner, more efficient, and safer. Here the focus is on flexibility, innovation, and the concept that “less is more”. For example, laptops are smaller and more portable than desktop computers, cell phones are smaller, more powerful, and more transportable than traditional phones, automobile manufacturing currently emphasizes more flexible design and production techniques, greater fuel efficiency and increased safety.
A major shift appears to be underway in Europe in the relationship between national, regional, and local control over health sector decision-making. Since World War II, a central thrust of health policy has been to decentralize key dimensions of decision-making authority to increasingly lower levels of government, as well as (in Social Health Insurance systems and recently in some tax-based systems) to private sector organizations.1 This strategy, to adapt Kondratiev's business-cycle framework,2 has been one of two overlapping ‘long waves’ that helped frame structural decisions in most Western European health systems. The second wave—market-influenced-entrepreneurialism—has run simultaneously with decentralization since the late 1980s. However, while this second, market-oriented wave has generated considerable controversy in some health policy circles, the concept of decentralization was readily accepted in many national policy contexts. As a result, over the second half of the 20th century, expanded decentralization of authority to regional, municipal and non-governmental control has become part of the ‘received wisdom’ about what good health policy should include. In the tax-funded health systems in Nordic countries, for example, most administrative and managerial responsibility as well as substantial political (policy) and fiscal decision-making control has been decentralized inside the public sector: from national to regional level (somatic hospitals in Norway in 1970; mental hospitals in Sweden in 1967), from regional to municipal level (elderly residential care in Sweden in 1992), and from national to municipal level (effective decision-making control over central hospitals in Finland in 1993). In the tax-funded health systems in Southern Europe, most administrative and managerial as well as many political (but not key fiscal) responsibilities were devolved from national to regional governments in Spain (to the 17 autonomous communities from 1981 to 2003), and in Italy (to 22 regional governments starting in the late 1980s). In social health insurance funded countries in continental Europe such as Germany and the Netherlands, most administrative and managerial as well as many fiscal (but not key political) decisions have long been delegated to private not-for-profit bodies (sickness funds and hospitals), under a form of ‘enforced self-regulation’ grounded in explicit national statutory responsibilities.3 In many cases, this particular form of decentralization has been in place since those systems’ inception. In the more state-based social insurance systems that have emerged since 1990 in many Central European countries, various forms of decentralization have been utilized. Reacting strongly to the prior highly centralized Semashko model, countries decentralized ownership of hospitals from national to regional (Hungary) and local (Estonia, Poland) governments. The Czech Republic even termed its decentralization of hospital ownership to municipal governments as ‘privatization’. In similar fashion, centralized funding structures of the Communist period were decentralized into regional social health insurance funds in countries such as Poland, the Czech Republic and Slovakia. The strategic role of decentralization was further strengthened by changes in overall governmental structures in Europe. During the 1980s and 1990s, national governments increasingly ceded areas of sovereign power upward to European Union bodies, while at the same time that they were losing responsibilities downward to increasingly assertive regions—a process captured by the popular 1990s discussion about a ‘Europe of Regions’. This overall reduction in the role of national governments served to reinforce the health sector experience that the era of centralized power at the national level in Europe was fast receding. In the first years of the 21st century, however, this conventional wisdom has started to come undone. Far from continuing to recede, the role of the state in the health sector has begun to strengthen measurably. Instead of reinforcing the continued decentralization of authority away from national governments, state institutions have reversed course and are seizing responsibility for substantive political and fiscal decision-making in European health care systems. It now appears that in the near-term future only administrative and managerial authority—e.g. day-to-day operating decisions—will remain decentralized to lower level and/or non-governmental organizations. These counter-indications can be observed in many of the health systems noted earlier. In the tax-funded system in Norway, the national government took over political and administrative/managerial responsibility for all hospitals in the entire country in January 2002, removing control from the 19 regional governments (counties) that had previously owned and operated the public hospitals and transferring the administrative role to five newly created regional bodies appointed from Oslo. The national government also set out new rules for how these regions were to manage their hospitals—as ‘public enterprises’. Fiscal responsibility for health care remained, as before, a national responsibility. In Denmark, the national government initiated a major re-structuring of the health sector in January 2006. In the new configuration, the number of regional governments was reduced from 14 to 5, and their powers were greatly reduced. Fiscal and most political responsibilities were centralized back to the national government, with certain prevention and chronic care issues being re-allocated to the municipalities (also consolidated, from 271 to 98). At the end of these changes, the new regions retained little more than administrative and managerial responsibility for hospitals. A similar pattern of regional consolidation and a strengthening of the state role appears to be underway in Sweden and Finland. In Sweden, a royal commission is expected to recommend that the number of regional level governments (which have responsibilities for hospital and also primary care) be reduced from the current 21 to between 6 and 8. Similarly, in Finland, the national government is expected to propose that the number of central hospital districts, currently 22, be reduced to 18, and also that the number of municipalities (responsible for primary, nursing home and home care services) be reduced from 450 to about 250. In the United Kingdom, similar recentralization can be seen in the transformation of England's Regional Health Authorities from line to support functions, as well as in current plans to reduce the number of Primary Care Trusts from 300 to 150. In Ireland, key operating responsibilities were recently shifted from regional health care boards to a health executive at central level and the regional boards were abolished. A parallel, if less aggressive, thrust toward more state control over both political and fiscal decisions can also be observed in several social health insurance funded countries. In the Netherlands, the national government in 2006 changed the health system's funding structure from a sliding 50% employee/50% employee paid model to a 100% individually paid fixed premium, supplemented by social assistance funds (e.g. taxes) for low income citizens. The Dutch government also, since the late 1990s, has been ratcheting up the percentage of total expenditures for which the private not-for-profit sickness funds are at risk, forcing funds to manage their money more efficiently. In Germany, the federal government in 2009 is scheduled to take on responsibility for pooling all social health insurance contributions and then allocating them to the sickness funds on a prospective, risk adjusted, capitation basis. While this funding model has been in place in the neighboring Netherlands for many years, in Germany it would represent a major move toward centralizing fiscal responsibilities away from the private not-for-profit sickness funds and into the hands of a national government body. In Central Europe, Poland, in 2003, pulled operating control over its social health insurance system away from 17 regional funds and back into the Ministry of Health. From the perspective of national health policymakers, this process of re-centralization appears to reflect a complex set of concerns. Structurally, there is substantial worry about the aging of their populations (e.g. more elderly), the rapid growth of expensive new clinical technologies, and the economic constraints on health sector funding generated by European regionalization as well as the globalization of markets. Administratively, there is evidence in countries like Finland and Norway (also concerns in Denmark) that local control over health sector decision-making has led to increased disparities in services provided and in outcomes to vulnerable populations—in short, that decentralization has heightened equity problems. Economically, there are worries that local finance bases are insufficient to fund expensive future care needs, and that local administrative arrangements are inefficient and duplicative. Politically—an important factor in Northern European tax-funded countries—there is a sense among national politicians that they are being blamed when the health system fails to meet the expectations of the citizenry, and that national policymakers need to have the necessary organizational levers to correct these problems. Technically, the introduction of electronic medical records and other computerized reporting systems has reduced the transaction costs of information and made it feasible to more closely monitor health system performance from a central level. While many of these dilemmas with decentralization were predicted earlier in theoretical assessments,4 one can see strong elements of their concrete manifestation in the current movement toward re-centralization. Moreover, since these causal factors are long-term in nature, their recent importance lends strength to the argument that re-centralization may indeed represent a long-term structural shift in national health strategies. Several important questions arise from these examples of re-centralizaton in both tax funded as well as social health insurance funded health systems. One is whether the observed changes represent more than just the normal ebb-and-flow of policy development in European health systems, and instead signal a fundamental shift in the overall pattern of these decisions. A related question is whether political and fiscal authority will continue to migrate from regional and municipal to national government, leaving mostly administrative and managerial forms of control at the lower levels. The underlying issue here concerns the mix of national and local authority that typically exists within most European health care systems, and whether the main bias in structuring that mix might be changing from one favouring decentralizing to local governments into one that favors centralizing authority back to national governments. Posed more provocatively, one might ask whether a new “long wave” of re-centralization has now begun, pointing toward a health policy future of stronger national governments and weaker regional, local, and delegated private (SHI) institutions. There are—as Kuhn's theory about the complexities of paradigm shift would predict5—several confounding factors in arriving at satisfactory answers to these questions. One issue concerns whether a new ‘long wave’ of re-centralization can co-exist comfortably—as decentralization did—with the parallel long-wave pattern of market-influenced entrepreneurial measures, particularly in tax-funded health systems. Will re-centralization and entrepreneurialism reinforce each other, as happened previously with decentralized local units? Second, there are several exceptions to this broad pattern of increasing re-centralization across European health systems. One clear exception is in countries with serious ethnic conflicts, for example Bosnia-Herzegovina and Macedonia in the Balkans, and also in Belgium. Recent history suggests that decentralization may be essential in these highly charged political environments, in that various forms of local control are typically linked to the survival of the state itself. Another conceptually messy question concerns the pattern of continued regional decentralization of health sector decisions in Southern European countries like Italy and Spain. Regional governments in these two countries have fiercely defended their recently gained authority in the health sector, and have forced their less convinced central governments (Spain in 2003, for example) to tread carefully in designing new national programs to monitor performance or set standards for quality and outcomes. Of course, Spain and Italy both have histories of earlier regional sovereignty. Moreover, both are geographically larger and have bigger populations than Nordic countries—although they are roughly equal in size to the United Kingdom and also Poland. There is, further, within both Italian and Spanish regions a tendency toward greater internal centralization inside the regions themselves. Despite these caveats, however, it appears that Italy and Spain are pursuing greater decentralization at the same point in time that Northern European countries are shifting away from decentralization in their health systems. This brief review of recent health sector patterns raises a series of questions that do not allow for easy answers. A further complicating factor is the apparent lack of fit between continued local control over services to the elderly (home care, social assistance, also nursing home care) and increasing central control over fiscal and policy decisions in the overall health sector, which implies that re-centralization may soon confront key structural limitations. The current distribution of health sector evidence does suggest, however, that many European health systems will continue to see a tightening of state controls, especially over fiscal and quality-related matters. In this clash between national and local governments, it would appear that, on balance, democratic control at the national level will strengthen, taking increased authority over political and fiscal decisions, while democratic control at the regional and municipal level will weaken, and be increasingly focused only on administrative and managerial decisions. Moreover, given the rapid melting of public–private boundaries within many European health systems, this greater state role will likely be combined with growing public as well as private sector entrepreneurialism, despite the appearance that greater reliance on market-oriented decisions contradicts tighter state control over health system behaviour. While the particular balance between increased state controls and increased entrepreneurial initiatives will vary from country to country, this new blend of two ‘long waves’, with increasing levels of state authority over key health sector decisions, will likely define the future policymaking framework for many European health systems in the near-term future. Earlier versions of this argument were presented at the Third International Health Policy Conference in Jerusalem (December 2006) and the Annual Meeting of the European Public Health Association in Helsinki (October 2007). This version has benefited from comments made by a number of colleagues at both meetings, and especially from Josep Figueras, David Chinitz and Charles Phelps. An earlier version of this article is included in the conference proceedings of the Jerusalem meeting.
Open access
Health Systems, Economic Evaluations, Quality of Life
INTRODUCTION Wherever you go, there are children who vomit. Causes of acute vomiting episodes include infections, minor head injury, gastrointestinal obstruction, and other surgical conditions. Chronic vomiting or recurrent vomiting is less well categorised, but includes regurgitation due to gastroesophageal reflux, allergic and eosinophilic diseases of the gut, chronic gastrointestinal dysfunction, metabolic disturbance, disease of the central nervous system, and disorders such as cyclical vomiting syndrome. It has even been noted that in children it can be a “symptom of almost any disease system” (1). This article outlines the mechanics and mechanisms of emesis and related reflexes, such as belching and gastroesophageal reflux, and highlights how knowledge of the underlying physiology has implications for understanding functional upper gastrointestinal tract disease in children. In addition, we review a number of challenging areas of paediatric gastroenterology involving nausea and vomiting. The authors use the following terminology: Vomiting is a lay term, used by patients and their families, to describe previously swallowed food and gastrointestinal secretions coming up the oesophagus and out of the mouth by any mechanism. Regurgitation describes the apparently effortless movement of gastric contents from stomach to oesophagus and out of the mouth. Emesis describes the forceful expulsion (vomiting) of stomach contents out of the mouth by vigorous contraction of the anterior abdominal wall muscles and diaphragm following activation of the emetic reflex. It is vital that clinicians distinguish between regurgitation and emesis, because when they become pathological, the treatment for each is different. Inappropriate treatment risks failure, and surgical therapy for regurgitation due to gastroesophageal reflux is likely to worsen the symptoms of emesis. The emetic reflex is triggered by a wide range of peripheral or central stimuli (2). Inputs to the “vomiting centre” (the collection of nuclei in the brainstem coordinating the emetic motor outputs) include gastrointestinal vagal afferents, the area postrema (“chemoreceptor trigger zone,” subject to direct influence by blood and cerebrospinal fluid–borne factors), vestibular system (motion sickness and inner ear disease), and stimulation of the pharynx. Severe abdominal pain is also a potent stimulus, but the pathways by which it induces emesis are unclear; although the noxious stimuli are conveyed in the splanchnic afferents, stimulation of these afferents does not evoke reflex emesis, in contrast to stimulation of abdominal vagal afferents. The emetic reflex also can be activated by stimulation of more rostral regions of the brain (eg, hypothalamus, limbic system) and by unpleasant sights or smells. The reflex also is amenable to Pavlovian conditioning, but relatively little is known of the descending pathways involved and their clinical significance. However, it is likely that the threshold for activation of the reflex by a number of stimuli is capable of modulation from higher brain regions, and this is supported by observations that sensitivity to motion sickness is a predictor of emesis to anticancer chemotherapy, postoperative nausea, and vomiting and pregnancy sickness (2). The emetic reflex may be considered in 2 phases—the prodromal phase and the ejection phase. The prodromal phase is characterised by nausea, an unpleasant but not painful sensation related to the upper abdomen, associated with a desire to vomit or a feeling that vomiting is imminent. It may precede emesis or it may occur in isolation (2), as can emesis itself. Emesis may alleviate nausea. The physiological basis of nausea remains poorly understood, but there is a strong association with gastric antral dysrhythmia and a large increase in the plasma levels of arginine vasopressin (3). Nausea is often accompanied by autonomic events, including sweating, peripheral vasoconstriction (causing pallor), tachycardia, reduced gastric secretion and pupil dilatation due to sympathetic nervous activity, and increased salivation due to parasympathetic stimulation (2). The central nervous systemic pathways involved in the genesis of the sensation of nausea are not known, although the inferior frontal cortex has been implicated. The ejection phase consists of retching and vomiting. First, there is a vagally mediated relaxation of the stomach and the lower oesophageal sphincter. A retrograde giant contraction originating in the mid-small intestine sweeps to the stomach, and is also under vagal efferent control. This contraction probably accounts for the frequent presence of bile in vomitus, except when pyloric obstruction is present. Tonic longitudinal contraction of the pharyngoesophageal junction pulls up the oesophagus, helping to open up the gastroesophageal junction. Then retching begins, with the anterior abdominal wall muscles and entire diaphragm (including the crura) contracting synchronously, with displacement of the abdominal oesophagus and gastric cardia through the crural hiatus into the thorax. Although gastric contents may enter and leave the lower oesophagus, they are not ejected. During vomiting, the perioesophageal diaphragm (ie, the right crus) relaxes, and the expulsion of gastric contents is achieved by the somatic muscles compressing the relaxed stomach. In the dog, a retrograde-propagated pharyngoesophageal contraction promotes the forcible ejection of gastric contents from the mouth (4), but it is unclear whether this occurs in humans. The purpose of the emetic reflex is defensive: to remove contaminated food from the upper gastrointestinal tract (2). Nausea stops further ingestion and facilitates learned aversion. It is an aversive stimulus, much more so than pain (5). The emetic reflex is a protective gastrointestinal reflex and in the normal course of events should be activated only occasionally; however, chronic gastrointestinal disease or dysfunction may result in frequent activation. In some neurologically impaired children, the central neurological damage appears to result in loss of inhibition, or hypersensitisation of the emetic reflex, which is then activated in the course of normal everyday activity. The belch is a vago-vagal reflex that permits oral expulsion of excessive intragastric air. Accumulation of gas in the gastric fundus and distension of the region of the cardia results in sudden and complete transient relaxation of the lower oesophageal sphincter (6), accompanied by relaxation of the diaphragmatic crus (7). A common cavity phenomenon occurs, attributed to reflux of air and other gastric contents into the oesophagus, with equalisation of gastric and oesophageal pressure; 1 or more belches may then take place as air is expelled (8,9) facilitated by contraction of anterior abdominal muscles. Note that the somatic motor changes during belching are similar to those occurring during vomiting, although they are considerably less forceful, and from the person's point of view, feel effortless. Unlike activation of the emetic reflex, there is no prodrome of nausea or associated autonomic events, such as sweating or vasoconstriction. Gastroesophageal reflux is the apparently effortless leakage of gastric contents (including food and gastric secretions) up into the oesophagus. It occurs when the mechanisms of oesophagogastric competence malfunction or are overcome by exceptional factors. Episodes of gastroesophageal reflux (GER) may occur in normal, healthy individuals without significant consequences. Gastroesophageal reflux disease (GERD) is present when the reflux results in significant symptoms or harm. A major factor in the occurrence of GER is dysfunction of the mechanism of lower oesophageal sphincter complex (ie, the smooth-muscle lower oesophageal sphincter [LOS] and the encircling right crus of the diaphragm). The most common mechanism of GER, in healthy individuals and in patients of all ages, is transient lower oesophageal sphincter relaxations (TLOSR); in other words, LOS resting pressure is normal but reflux occurs during episodes of a sudden, brief drop in pressure to near zero, which is not associated with primary oesophageal peristalsis induced by swallowing (10–15). This is more frequent in the immediate postprandial period and in the presence of gastric distension, and is accompanied by selective and complete inhibition of the crural diaphragm. TLOSRs can be triggered by activation of vagal afferents supplying the gastric fundus and cardia, and the resulting reflex motor responses are presumed to be coordinated in the brainstem (13,16). The normal physiological process most closely related to TLOSR is belching (8), although again the relaxation of the crural diaphragm and the LOS is reminiscent of the mechanics of emesis. Other mechanisms of GER include very low LOS resting pressure, downward drifts in resting pressure, reflux during swallow-induced relaxations, and GER due to abdominal straining (17,18). LOS length, or lack of it, especially the abdominal oesophagus, influences the effectiveness of the LOS as a reflux barrier. Sliding hiatus hernia is common in patients with GERD. This will dissociate the diaphragmatic crus from the LOS and disrupt antireflux mechanisms (19–21). Conversely, a long intraabdominal oesophagus will have antireflux properties because it is subject to intraabdominal pressure that will tend to compress it closed. In a nonvomiting species, such as the rat, the abdominal oesophagus is disproportionately long and narrow compared with humans. There is evidence that if the distal oesophagus is replaced by a tube of sufficient intraabdominal length, then reflux is prevented even in the absence of the LOS (22,23). In adults with reflux, relatively small quantities of gastric contents reach the mouth, but in children, the amounts refluxed may be much greater and may result in a large proportion of the recently ingested feed effortlessly pouring out of the mouth. Consideration of the underlying physiological processes should make clear the difference between reflux vomiting and vomiting due to activation of the emetic reflex. Reflux vomiting is akin to belching; there is no prodrome and it appears effortless. Emetic vomiting is preceded by feeling unwell with nausea, pallor, sweating, and tachycardia, and it is accompanied by violent contractions of the anterior abdominal wall muscles and diaphragm, leaving the subject feeling drained and exhausted. CLINICAL IMPLICATIONS FOR CONFUSION BETWEEN EMESIS AND GER Chronic vomiting in children may appear to be a result of GER and regurgitation. It is reported to be particularly common in neurologically impaired children and is attributed to central nervous system dysfunction (24); however, it is not always easy to get the diagnosis right. The importance of understanding the pathophysiology and the potentially devastating effects of misdiagnosis is emphasised by considering the effects of inappropriate fundoplication. Many children, particularly those with neurological impairments, do not show a full symptomatic response to antireflux medication. They are considered to have severe reflux disease and to require surgery. However, a high failure rate has been documented (25,26) and an alternative explanation must be considered. Failure to respond to antireflux therapy may not indicate severe GERD, but that some or all of the symptoms are due to another cause (eg, activation of the emetic reflex) (24). Many of the children with failure to respond to antireflux therapy have symptoms other than those of GERD. One prominent troublesome symptom that persists after fundoplication is retching (25–33), but this is a component of the emetic reflex and not a symptom of GER (24). These children may also have evidence of nausea (34). Performing fundoplication on a child whose symptoms are wholly or partly due to activation of the emetic reflex is liable to result in marked postoperative problems (35). Fundoplication does not deal with the underlying causes of emesis, and by creating a valvular mechanism at the oesophagogastric junction and obstructing the movement of gastric contents back up the oesophagus, symptoms are made worse. The child will retch repeatedly, and the accompanying nausea will persist. Children who retch preoperatively have a much higher chance of retching following fundoplication compared with nonretchers (35). In a report on anatomical wrap failure (eg, wrap herniation/wrap disruption) following laparoscopic fundoplication in adults, Soper and Dunnegan (36) found a significant association with forceful contraction of the diaphragm. The process that appears to generate the greatest pressures, and, moreover, the greatest pressure gradient from the abdomen to the thorax, is retching. Retching generates huge forces capable of causing wrap disruption, and in particular, forces that specifically drive the wrap through the crural hiatus (ie, wrap herniation into the thorax). Using radioopaque markers, Johnson and Laws (37) demonstrated elevation of the oesophagogastric junction through the crural hiatus just before retching and vomiting, with displacement of the cardia and distal oesophagus cranial to the crus, into the thorax. In a subsequent study of the mechanics of vomiting in the cat, McCarthy and Borison (38) described retches as a metronomic series of pulses, with brief negative-pressure pulses in the thorax mirrored by positive-pressure pulses in the abdomen, progressively building up a substantial transdiaphragmatic pressure gradient (200–300 mmHg) and culminating in a prolonged positive abdominal and thoracic pressure wave with sustained abdominal contraction and elevation of the diaphragm and vomit expulsion. During retching, there was a pulsing cephalad displacement of the oesophago-gastric junction, with the fundus of the stomach drawn through the diaphragmatic hiatus, into the thorax (38,39). These reports indicate that there is normally a substantial movement of the gastroesophageal junction during retching and vomiting, with significant pressure changes. Fundoplication in the retching child sets the scene for anatomical wrap failure. Repeated episodes of retching drive the oesophagogastric junction through the diaphragmatic hiatus into the thorax and pull the wrap apart. Patients classically present with increasing postoperative retching (wrap intact), which may later progress to retching and vomiting, associated with subsequent documentation of wrap disruption. Retching precedes wrap failure and is a cause rather than a symptom of wrap herniation. Not only does fundoplication fail to relieve emesis but there is also evidence that fundoplication may even sensitise the emetic reflex, reducing the threshold for activation of retching and emetic vomiting. Some children may develop new onset of retching after fundoplication, and parents of children who retched before surgery believe the postoperative retching is worse. Gastric dysrhythmias, as recorded by the surface electrogastrogram, may worsen after fundoplication, correlating with retching symptoms (24). In an animal model of fundoplication (the ferret), fundoplication was followed by an increased sensitivity to a low dose of the centrally acting emetic loperamide (40). A possible mechanism of sensitisation is the presence of peripheral nerve and muscle damage and scarring as a result of surgery. Histological examination of the fundoplication in the ferret shows clear evidence of scar tissue in the wall of the distal oesophagus and the inner gastric layer of the fundoplication wrap, in the region of the cardia (41). This effect may be even more marked in disrupted wraps. In ferrets with disrupted fundoplications, we observed an increased retching response to induction of general anaesthesia compared with intact fundoplications (in turn greater than controls), together with evidence of gastric dysmotility and increased scar tissue and nerve damage (41). This has implications for redoing fundoplications after wrap disruption, with a higher risk of failure, increasing damage, physiological dysfunction, and ever-increasing symptoms. CHALLENGES IN NAUSEA AND VOMITING IN PAEDIATRIC GASTROENTEROLOGY How Do We Identify Nausea in Young Children and Neurologically Impaired Children? Nausea is a self-reported subjective sensation, so how can the presence of this significant clinical symptom be established in patients who are unable to self-report, such as young children and those with severe neurological impairments? The situation is analogous to that in animals, in which behavioural changes and physiological markers have been used as surrogate markers for the presence of the sensation (2). Traditional teaching states that pain from reflux oesophagitis causes food refusal in children. In our study of children before and after Nissen fundoplication, we observed a striking association between food refusal and retching, strongly suggesting that in the context of recurrent vomiting, food refusal is a manifestation of the nausea that accompanies the emetic reflex (34). Refusal of specific foods is particularly suggestive of nausea-induced taste aversion. An infant with activation of the emetic reflex secondary to intolerance of cow's milk protein may refuse whole-protein cow's-milk formula, but will readily drink a hydrolysed formula or water. Parents of a child with emesis may say that they appear unsettled or “pull a face” immediately before emesis, again suggesting distress and nausea. Other indicators of nausea may include the surface electrogastrogram; development of a gastric dysrhythmia in response to food may indicate nausea in the same way that the appearance of tachygastria correlates with the onset of motion sickness (42). Measurements of plasma vasopressin have not been made in children with suspected nausea, but such measurements may be helpful in ensuring that this distressing symptom does not go unrecognised and hence untreated. Cyclical Vomiting Cyclical vomiting is a that is most reported in children 2 to but which can also occur in It is characterised by a of or more of acute nausea and vomiting to with to with of and central nervous system disease of this a to into the physiology and of the emetic reflex. The vomiting is particularly and prolonged and is associated with abdominal pain in of is the that the nausea is not by vomiting The in is for at 2 It is an of a in which there is and prolonged activation of the emetic reflex without an emetic and as such may a in which the emetic reflex has become under include of abdominal afferents, such that normally stimuli evoke emesis in these such a mechanism be with the high of abdominal pain in patients with A in the brainstem nuclei that to or the sensitivity of the emetic reflex as an or vomiting a number of with properties a range of emetic stimuli (eg, is considered to the a in these then this an to to mechanisms in the emetic such as and metabolic a number of of the and are known to be potent emetic in their as well as lower the threshold to other emetic stimuli such as which a in the of in the brainstem nuclei involved in emesis, such as the to induction of emesis without an stimulus, although often is as a There is evidence for some of in with in the also have been to the increased of in the of children with These may into the that the sensitivity of the emetic reflex. There is evidence that nausea responses to are higher in compared with and The of the effects of in the and their subsequent into the for the treatment of and emesis and postoperative nausea and vomiting to a significant in of this distressing effect in children and These by the activation of on the peripheral and central of abdominal vagal afferents, with the peripheral of the afferents activated by from in the of the The are particularly in the acute phase of but are less or in the and the for to this phase was 1 of the that to an effect of in emesis, in (eg, and in patients anticancer The is the for the a The with this of that they a effect with stimuli acting abdominal vagal afferents, the area and the vestibular system, for a central of the nuclei the of the emetic reflex This is the of a selective such a of and a on that it may be possible to a or for use in humans. The of of the only is under but a study has evidence that it emesis in patients with severe to other we are to the of children with chronic vomiting we to distinguish between activation of the emetic reflex and GERD. nausea other prodromal such as sweating, or and retching point effortless A and is Parents of children with GER distinguish the regurgitation of GER from the emesis of Parents who report that their child vomiting the stomach is are the forceful and of activation of the emetic reflex. In the has increasing evidence that that the emetic reflex are the cause of symptoms previously attributed to GER (eg, eosinophilic oesophagitis and allergic oesophagitis in suspected should not be for evidence of they should be other specific causes of and for evidence of emesis or general to be with shows it does not make a diagnosis of reflux An of retching during a contrast is liable to be as reflux and hiatus at are are subjective and can only be this of more and the reports of as a common cause of vomiting in children with severe neurological The and of these children with recurrent emesis due to dysmotility our greatest
Changes in locations of FIRE and business services firms in Hong Kong during 1980–2000 could be characterized by trends of both centralization and decentralization. A heavy concentration of finance firms in the CBD is highly significant, implying the presence of strong forces promoting the spatial concentration of the finance firms. Insurance and business service firms tend to locate mainly in areas adjoining the CBD in order to enjoy the externalities or support services, which CBD offers. Volatility in rents has also provided opportunities for firms to relocate within the CBD at lower cost. In contrast, real estate firms tend to decentralize away from Hong Kong Island due to cheaper rents. The important finding of the sample survey analysis is that non-traditional factors such as office buildings with IT facilities have emerged as dominant factors determining choice of location. For instance. during the survey period, finance firms considered office buildings with IT facilities as the most important factor, while business service firms considered sufficient floor-space as the second most important factor after rent in choosing the present location.
The thesis is about a breadth-first exploration of logical concepts in cryptography and their linguistic abstraction and model-theoretic combination in a comprehensive logical system, called CPL (for Cryptographic Protocol Logic ). We focus on two fundamental aspects of cryptography. Namely, the security of communication (as opposed to security of storage ) and cryptographic protocols (as opposed to cryptographic operators ). The logical concepts explored are the following. Primary concepts: the modal concepts of belief, knowledge, norms, provability, space, and time. Secondary concepts: belief with error control, individual and propositional knowledge, confidentiality norms, truth-functional and relevant (in particular, intuitionistic) implication, multiple and complex truth values, and program types. The distinguishing feature of CPL is that it unifies and refines a variety of existing approaches. This feature is the result of our wholistic conception of property-based (modal logics) and model-based (process algebra) formalisms. We illustrate the expressiveness of CPL on representative requirements engineering case studies. Further, we extend (core) CPL (qualitative time) with rational-valued time , i.e., time stamps, timed keys, and potentially drifting local clocks, to tCPL (quantitative time). Our extension is conservative and provides further evidence for Lamport's claim that adding real time to an untimed formalism is really simple. Furthermore, we sketch an extension of (core) CPL with a notion of probabilistic polynomial-time (PP) computation. We illustrate the expressiveness of this extended logic (ppCPL) on tentative formalisation case studies of fundamental and applied concepts. Fundamental concepts: (1) one-way function, (2) hard-core predicate, (3) computational indistinguishability, (4) ( n -party) interactive proof, and (5) ( n -prover) zero-knowledge. Applied concepts: (1) security of encryption schemes, (2) unforgeability of signature schemes, (3) attacks on encryption schemes, (4) attacks on signature schemes, and (5) breaks of signature schemes. In the light of logic, adding PP to a formalism for cryptographic protocols is perhaps also simple and can be achieved with an Ockham's razor extension of an existing core logic, namely CPL.
Tianjie Cao, Shi Ming Huang, Hui Cui, Yipeng Wu · 5 authors
How to leak authoritative secrets in an elegant way? The paper aims to solve this problem. The desired security properties i.e. Semantic-Security; Recipient-Designation; Verification-Dependence; Designated-Verifier Signature-Verifiability; Public Signature-Verifiability; Recipient-Ambiguity; Designated-Verifier Recipient-Verifiability; Public Recipient-Verifiability; Signer-Ambiguity; Signer- Verifiability are specified in secret leakage. Based on Chow-Yiu-Hui's ID-based ring signature scheme and techniques of zero-knowledge proof, an ID-based controlled secret leakage scheme is proposed. The proposed scheme satisfies all specified security properties and can be used in trust negotiation.
In this paper, we give an efficient short constant-size group signature scheme that is secure in standard model based on strong Diffie-Hellman assumption. We achieve this result by combining a variant signature scheme of the one presented by Okamoto and non-interactive zero knowledge proof used by Boyen and Waters. Compared with the most efficient group signature scheme without random oracle, our scheme has a much shorter public key length and signature length, and needs less computation.
The Congregation of the Blessed Virgin Mary (CBVM), a Catholic order founded in the early 1800s, was faced with a series of strategic concerns, including an aging clerical population, a changing laity, reduced finances, very limited vocations, and an evolving mission. Some of these concerns faced the Catholic Church in America as a whole (including sexual abuse, not discussed in this case) and several of these issues were also facing the Catholic Church worldwide. The serious matters facing them were threatening the continued viability of the order in America, and the guidance they were receiving from Rome - instruction to decide which of three suggested models for restructuring they would adopt - seemed to back them into a corner, requiring selection from among several strategies not devised by their membership and commitment to the selected strategy going forward. Change was necessary, but one of the major concerns of the order was that it remain consistent with its stated mission while adapting to a new environment and “operating system.” Their decisions were driven by Rome, but the decisions were not made by Rome; the CBVM was as autonomous in its decision-making as any decentralized international organization.