61 research outputs found
Social Attributes And Economic Instability In Africa
How do the social characteristics of African economies affect their relative economic stability? This paper offers a new nominal definition of economic instability in terms of average standard deviations from the exponential growth path suggested by neoclassical growth theory under ideal conditions. We used the portion of the population that subsists on agriculture as an indication of how diverse and adaptable any particular economy is. Literacy rates may serve as a proxy for the quality and adaptability of the labor force in the various countries. Other variables used are urban population as a percentage of total population, life expectancy, infant mortality rates and the corruption perception index. These variables were all statistically significant in explaining economic instability with the exception of corruption perception index and infant mortality rates that were statistically insignificant
Social Attributes And Economic Instability In Africa
How do the social characteristics of African economies affect their relative economic stability? This paper offers a new nominal definition of economic instability in terms of average standard deviations from the exponential growth path suggested by neoclassical growth theory under ideal conditions. We used the portion of the population that subsists on agriculture as an indication of how diverse and adaptable any particular economy is. Literacy rates may serve as a proxy for the quality and adaptability of the labor force in the various countries. Other variables used are urban population as a percentage of total population, life expectancy, infant mortality rates and the corruption perception index. These variables were all statistically significant in explaining economic instability with the expectation of corruption perception index and infant mortality rates which were statistically insignificant
What’s in a Name? On Language, Concept Formation, and the Definition Disputes in the Entrepreneurship Literature
When it comes to entrepreneurship, the conceptual framework of economics is disjointed: On the one hand almost everyone agrees that entrepreneurial initiative and creativity are critical for economic progress. On the other hand neither initiative, nor creativity, plays any role in formal models of choice and economic behavior. This creates a blind spot on the behavioral aspects of entrepreneurship. It has also spawned a dichotomy between the functional and behavioral aspects of entrepreneurial actions in the economics literature. Most importantly, it prevents economists from developing a coherent unifying theoretical framework for making sense of entrepreneurs. The problem is reinforced by the language and semiotics of economics and is reflected by the lack of behavioral research on entrepreneurs in the literature. As suggested by Baumol (1968 and 2010) initiative and creativity are the obvious defining traits of entrepreneurship. Even so, the literature has spawned a variety of different and occasionally nonsensical definitions of entrepreneurship that obscure and divert our attention away from these defining characteristics. The divergent definitions in the literature are further exacerbated by discordant conceptual structures and ideas that cannot easily be translated from one field to another. In the absence of a unifying framework, different fields have focused narrowly on entrepreneurship from dissimilar angles. The bottom line is that researchers in different fields sometimes rely on such incompatible definitions of what constitutes entrepreneurship that interdisciplinary dialogue is impossible. The end result is akin to the problem of radical translation between different languages. The paper concludes that the definition debates will not be resolved without a unifying structure that focuses on initiative and creativity as the defining attributes of entrepreneurship. This calls for some new tools and behavioral models that can explicitly account for initiative and creativity as integral aspects of human choices and actions
On Gluts, Effective Demand, and the True Meaning of Say's Law
The meaning of Say's Law may seem an issue of little relevance to economists today. It would seem, on the face of it, of interest only to historians of economics. Whatever Say's Law might mean, the one thing we economists know, or at least think we know, is that it was comprehensively refuted by John Maynard Keynes in his "General Theory of Employment, Interest and Money." Knowing the meaning of this ancient economic doctrine would appear a matter of no contemporary importance. Part of a Symposium entitled, "Say's Law Revisited", this paper argues that the disappearance of the guiding principles underlying Say's Law has grievously damaged our understanding of economic processes. The disappearance of Say's Law from amongst the conceptual tools employed by economists is in fact Keynes's most enduring legacy.Employment; Money
On the Economics of Say and Keynes' Interpretation of Say's Law
J. B. Say argued that commercial crises were the results of effective demand failures, except, unlike Malthus he did not naively attribute effective demand failures to overproduction given some absolute limit on people's willingness to consume. Instead, Say built a theory of recessions based on coordination failures. Many of Say's contemporaries failed to understand his arguments. This in turn led to an escalating series of misquotes and misinterpretations that ultimately ended up as Keynes' supply creates its own demand rendition of Say's law.
Direct single-molecule observation of calcium-dependent misfolding in human neuronal calcium sensor-1
Neurodegenerative disorders are strongly linked to protein misfolding, and crucial to their explication is a detailed understanding of the underlying structural rearrangements and pathways that govern the formation of misfolded states. Here we use single-molecule optical tweezers to monitor misfolding reactions of the human neuronal calcium sensor-1, a multispecific EF-hand protein involved in neurotransmitter release and linked to severe neurological diseases. We directly observed two misfolding trajectories leading to distinct kinetically trapped misfolded conformations. Both trajectories originate from an on-pathway intermediate state and compete with native folding in a calcium-dependent manner. The relative probability of the different trajectories could be affected by modulating the relaxation rate of applied force, demonstrating an unprecedented real-time control over the free-energy landscape of a protein. Constant-force experiments in combination with hidden Markov analysis revealed the free-energy landscape of the misfolding transitions under both physiological and pathological calcium concentrations. Remarkably for a calcium sensor, we found that higher calcium concentrations increased the lifetimes of the misfolded conformations, slowing productive folding to the native state. We propose a rugged, multidimensional energy landscape for neuronal calcium sensor-1 and speculate on a direct link between protein misfolding and calcium dysregulation that could play a role in neurodegeneration
Are we ready to track climate-driven shifts in marine species across international boundaries? - A global survey of scientific bottom trawl data
Marine biota are redistributing at a rapid pace in response to climate change and shifting seascapes. While changes in fish populations and community structure threaten the sustainability of fisheries, our capacity to adapt by tracking and projecting marine species remains a challenge due to data discontinuities in biological observations, lack of data availability, and mismatch between data and real species distributions. To assess the extent of this challenge, we review the global status and accessibility of ongoing scientific bottom trawl surveys. In total, we gathered metadata for 283,925 samples from 95 surveys conducted regularly from 2001 to 2019. We identified that 59% of the metadata collected are not publicly available, highlighting that the availability of data is the most important challenge to assess species redistributions under global climate change. Given that the primary purpose of surveys is to provide independent data to inform stock assessment of commercially important populations, we further highlight that single surveys do not cover the full range of the main commercial demersal fish species. An average of 18 surveys is needed to cover at least 50% of species ranges, demonstrating the importance of combining multiple surveys to evaluate species range shifts. We assess the potential for combining surveys to track transboundary species redistributions and show that differences in sampling schemes and inconsistency in sampling can be overcome with spatio-temporal modeling to follow species density redistributions. In light of our global assessment, we establish a framework for improving the management and conservation of transboundary and migrating marine demersal species. We provide directions to improve data availability and encourage countries to share survey data, to assess species vulnerabilities, and to support management adaptation in a time of climate-driven ocean changes.En prensa6,86
Adjuvant hyperthermic intraperitoneal chemotherapy (HIPEC) in patients with colon cancer at high risk of peritoneal carcinomatosis; the COLOPEC randomized multicentre trial
Background: The peritoneum is the second most common site of recurrence in colorectal cancer. Early detection of peritoneal carcinomatosis (PC) by imaging is difficult. Patients eventually presenting with clinically apparent PC have a poor prognosis. Median survival is only about five months if untreated and the benefit of palliative systemic chemotherapy is limited. Only a quarter of patients are eligible for curative treatment, consisting of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CR/HIPEC). However, the effectiveness depends highly on the extent of disease and the treatment is associated with a considerable complication rate. These clinical problems underline the need for effective adjuvant therapy in high-risk patients to minimize the risk of outgrowth of peritoneal micro metastases. Adjuvant hyperthermic intraperitoneal chemotherapy (HIPEC) seems to be suitable for this purpose. Without the need for cytoreductive surgery, adjuvant HIPEC can be performed with a low complication rate and short hospital stay. Methods/Design: The aim of this study is to determine the effectiveness of adjuvant HIPEC in preventing the development of PC in patients with colon cancer at high risk of peritoneal recurrence. This study will be performed in the nine Dutch HIPEC centres, starting in April 2015. Eligible for inclusion are patients who underwent curative resection for T4 or intra-abdominally perforated cM0 stage colon cancer. After resection of the primary tumour, 176 patients will be randomized to adjuvant HIPEC followed by routine adjuvant systemic chemotherapy in the experimental arm, or to systemic chemotherapy only in the control arm. Adjuvant HIPEC will be performed simultaneously or shortly after the primary resection. Oxaliplatin will be used as chemotherapeutic agent, for 30 min at 42-43 degrees C. Just before HIPEC, 5-fluorouracil and leucovorin will be administered intravenously. Primary endpoint is peritoneal disease-free survival at 18 months. Diagnostic laparoscopy will be performed routinely after 18 months postoperatively in both arms of the study in patients without evidence of disease based on routine follow-up using CT imaging and CEA. Discussion: Adjuvant HIPEC is assumed to reduce the expected 25 % absolute risk of PC in patients with T4 or perforated colon cancer to a risk of 10 %. This reduction is likely to translate into a prolonged overall survival
Population-level deficit of homozygosity unveils CPSF3 as an intellectual disability syndrome gene.
To access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked DownloadPredicting the pathogenicity of biallelic missense variants can be challenging. Here, we use a deficit of observed homozygous carriers of missense variants, versus an expected number in a set of 153,054 chip-genotyped Icelanders, to identify potentially pathogenic genotypes. We follow three missense variants with a complete deficit of homozygosity and find that their pathogenic effect in homozygous state ranges from severe childhood disease to early embryonic lethality. One of these variants is in CPSF3, a gene not previously linked to disease. From a set of clinically sequenced Icelanders, and by sequencing archival samples targeted through the Icelandic genealogy, we find four homozygous carriers. Additionally, we find two homozygous carriers of Mexican descent of another missense variant in CPSF3. All six homozygous carriers of missense variants in CPSF3 show severe intellectual disability, seizures, microcephaly, and abnormal muscle tone. Here, we show how the absence of certain homozygous genotypes from a large population set can elucidate causes of previously unexplained recessive diseases and early miscarriage.Sacchi Foundatio
Adolescent transport and unintentional injuries: a systematic analysis using the Global Burden of Disease Study 2019
Background: Globally, transport and unintentional injuries persist as leading preventable causes of mortality and morbidity for adolescents. We sought to report comprehensive trends in injury-related mortality and morbidity for adolescents aged 10–24 years during the past three decades. Methods: Using the Global Burden of Disease, Injuries, and Risk Factors 2019 Study, we analysed mortality and disability-adjusted life-years (DALYs) attributed to transport and unintentional injuries for adolescents in 204 countries. Burden is reported in absolute numbers and age-standardised rates per 100 000 population by sex, age group (10–14, 15–19, and 20–24 years), and sociodemographic index (SDI) with 95% uncertainty intervals (UIs). We report percentage changes in deaths and DALYs between 1990 and 2019. Findings: In 2019, 369 061 deaths (of which 214 337 [58%] were transport related) and 31·1 million DALYs (of which 16·2 million [52%] were transport related) among adolescents aged 10–24 years were caused by transport and unintentional injuries combined. If compared with other causes, transport and unintentional injuries combined accounted for 25% of deaths and 14% of DALYs in 2019, and showed little improvement from 1990 when such injuries accounted for 26% of adolescent deaths and 17% of adolescent DALYs. Throughout adolescence, transport and unintentional injury fatality rates increased by age group. The unintentional injury burden was higher among males than females for all injury types, except for injuries related to fire, heat, and hot substances, or to adverse effects of medical treatment. From 1990 to 2019, global mortality rates declined by 34·4% (from 17·5 to 11·5 per 100 000) for transport injuries, and by 47·7% (from 15·9 to 8·3 per 100 000) for unintentional injuries. However, in low-SDI nations the absolute number of deaths increased (by 80·5% to 42 774 for transport injuries and by 39·4% to 31 961 for unintentional injuries). In the high-SDI quintile in 2010–19, the rate per 100 000 of transport injury DALYs was reduced by 16·7%, from 838 in 2010 to 699 in 2019. This was a substantially slower pace of reduction compared with the 48·5% reduction between 1990 and 2010, from 1626 per 100 000 in 1990 to 838 per 100 000 in 2010. Between 2010 and 2019, the rate of unintentional injury DALYs per 100 000 also remained largely unchanged in high-SDI countries (555 in 2010 vs 554 in 2019; 0·2% reduction). The number and rate of adolescent deaths and DALYs owing to environmental heat and cold exposure increased for the high-SDI quintile during 2010–19. Interpretation: As other causes of mortality are addressed, inadequate progress in reducing transport and unintentional injury mortality as a proportion of adolescent deaths becomes apparent. The relative shift in the burden of injury from high-SDI countries to low and low–middle-SDI countries necessitates focused action, including global donor, government, and industry investment in injury prevention. The persisting burden of DALYs related to transport and unintentional injuries indicates a need to prioritise innovative measures for the primary prevention of adolescent injury. Funding: Bill & Melinda Gates Foundation
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