Miracle-dz/UniFAR-FTUs huggingface dataset:
Un estudio estadístico sobre el comportamiento de la cotización del peso mexicano frente al dólar y de su volatilidad

(Agradezco los comentarios de Agustín Carstens Carstens y Moisés Schwartz Rosenthal, así como la valiosa colaboración de Alexis Milo Caraza. Por último quisiera agradecer a Gabriela Estebanez Cabral por su cooperación en la elaboración de este documento. Las opiniones contenidas en el documento corresponden exclusivamente al autor y no representan el punto de vista del Banco de México.) ALEJANDRO M. WERNER Marzo, 1997
Structure to function: muscle failure in critically ill patients

Impaired physical function and reduced physical activity are common findings in intensive care unit (ICU) survivors. More importantly, reduced muscle strength during critical illness is an independent predictor of survival. Skeletal muscle wasting as a direct consequence of critical illness has been suggested as the cause. However, data on the physiological processes regulating muscle mass, and function, in these critically ill patients are limited as this is not only a technically challenging research area, but also the heterogeneity of the patient group adds complexity to the interpretation of results. Despite this, clinical and research interest in this area is growing. This article highlights the issues involved in measurement of muscle function and mass in critically ill patients and the physiological complexities involved in studying these patients. Although the data are limited, this article reviews the animal and healthy human data providing a rational approach to the potential pathophysiological mechanisms involved in muscle mass regulation in critically ill patients, including the established muscle wasting ‘risk factors’ such as ageing, immobility and systemic inflammation, all of which are common findings in the general critical care population.
Box-Jenkins’ Methodology in Predicting Maternal Mortality Records from a Public Health Facility in Ghana

The Millennium Development Goal (MDG) 5 advocated the reduction of maternal mortality rates significantly by 2015, however, maternal mortality rates continue to rise. Here, we modelled maternal mortality data for the years 2000 to 2013 obtained from a public hospital in Kumasi, Ghana. We applied the Box-Jenkins approach of univariate form of time series autoregressive integrated moving average (ARIMA). The output revealed that the ARIMA (1, 1, 1) model was most appropriate to model and predict monthly maternal cases with Akaike information criterion (AIC) value of 117.02 and Bayesian information criterion (BIC) value of 125.91. The Shapiro-Wilk normality test confirmed normality of the residuals. The Ljung-Box test on the residuals showed no serial correlation. The model was then validated based on the measures of accuracy. The results showed that the maternal mortality cases for the years 2000 to 2011 are high: minimum 3, median 11, mean 12 and maximum cases of 26 per month. The predicted mortality cases were 10 to 11 monthly for years 2012 to 2013, indicating that the target of MDG 5 could not be achieved by 2015. Fresh and perceptive strategies are urgently needed to arrest the unacceptably high death rates.
Do Unlisted Targets Sell at Discounts?

Academic literature, practitioners, courts, and regulators routinely assert that both private and subsidiary targets sell at discounts relative to public targets. However, the empirical evidence to support this conclusion is thin. Our work alters the methodology from prior research to avoid biases due to both one-sided sample truncation and Jensen’s inequality. Following these changes, we find no evidence that unlisted targets sell at discounts. Our results hold under a number of different approaches and after controlling for known determinants of acquisition pricing.
A Study of preconditioned Krylov subspace methods with reordering for linear systems from a biphasic v–p finite element formulation

A study was conducted on combinations of preconditioned iterative methods with matrix reordering to solve the linear systems arising from a biphasic velocity–pressure (v–p) finite element formulation used to simulate soft hydrated tissues in the human musculoskeletal system. Krylov subspace methods were tested due to the symmetric indefiniteness of our systems, specifically the generalized minimal residual (GMRES), transpose-free quasi-minimal residual (TFQMR), and biconjugate gradient stabilized (BiCGSTAB) methods. Standard graph reordering techniques were used with incomplete LU (ILU) preconditioning. Performance of the methods was compared on the basis of convergence rate, computing time, and memory requirements. Our results indicate that performance is affected more significantly by the choice of reordering scheme than by the choice of Krylov method. Overall, BiCGSTAB with one-way dissection (OWD) reordering performed best for a test problem representative of a physiological tissue layer. The preferred methods were then used to simulate the contact of the humeral head and glenoid tissue layers in glenohumeral joint of the shoulder, using a penetration-based method to approximate contact. The distribution of pressure and stress fields within the tissues shows significant through-thickness effects and demonstrates the importance of simulating soft hydrated tissues with a biphasic model.
Breeding soundness of beef bulls after circumcision: 33 cases (1980-1986).

Case records of 33 beef bulls that had preputial prolapses and underwent circumcisions were reviewed. Data retrieved included age, breed, duration of preoperative medical treatment, complications of surgery, length of time from surgery to first breeding, ability of bull to copulate, duration of active breeding, and complications resulting in breeding unsoundness. The mean age of all bulls was 3.5 years (1 to 7 years). Breeds represented included Santa Gertrudis (n = 13), Beefmaster (n = 8), Brangus (n = 7), Brahman (n = 4), and Angus (n = 1). The mean duration of medical treatment before surgery for all bulls was 16.4 days (2 to 38 days). There was no statistically significant difference between the mean duration of medical treatment before surgery between bulls that became breeding sound (16 days), compared with those that were breeding unsound (19 days). However, bulls requiring more than 14 days of medical treatment before surgery were approximately 3 times (relative risk, 2.8) more likely to develop postoperative complications than those bulls requiring 14 days of treatment or less. Eleven bulls (33%) developed one or more postoperative complications. The complications resolved in 4 bulls, but 7 were never able to breed. Of these 7 bulls, 4 had problems directly related to the circumcision, 2 had extensive fibrosis of the prepuce already present at surgery, and 1 was discharged from the hospital with no apparent complications but was never able to breed. Twenty-five of the 33 bulls (76%) were breeding sound for 1 or more years after surgery. (ABSTRACT TRUNCATED AT 250 WORDS)
Prognostic value of post-ischemic stunning as assessed by gated myocardial perfusion single-photon emission computed tomography: a subanalysis of the J-ACCESS study .

BACKGROUND To determine the prognostic value of post-ischemic stunning, the Japanese assessment of cardiac event and survival study by quantitative gated myocardial single-photon emission computed tomography (SPECT) (J-ACCESS) study was reevaluated. METHODS AND RESULTS Of the 4,031 patients of the J-ACCESS, the present study evaluated 1,089 who completed gated SPECT both after stress and at rest. To assess post-ischemic stunning, the following measurements (left ventricular volumes after stress minus volumes at rest) were made: Deltaend-systolic volume (DeltaESV), Deltaenddiastolic volume (DeltaEDV) and Deltaejection fraction (DeltaEF). Myocardial stunning defined either as DeltaESV >or=5 ml, DeltaEDV >or=5 ml or DeltaEF <or=5% was observed in 21%, 22%, or 26%, respectively. During a 3-year follow-up, 101 cardiac events occurred. Kaplan-Meier survival estimation indicated worse event-free survival rates in patients with dilated ESV, dilated EDV, LVEF <or=45%, DeltaESV >or=5 ml or DeltaEDV >or=5 ml than in those without, whereas DeltaEF <or=5% did not predict events. Multivariate analysis demonstrated that LVEF <or=45% was the independent predictor for cardiac events. Nevertheless, DeltaEDV >or=5 ml was also an independent parameter, in addition to LVEF <or=45%, to predict the combined endpoint of cardiac death, myocardial infarction, and revascularization, but excluding heart failure. CONCLUSIONS These results indicate that post-ischemic stunning, as assessed by gated SPECT, is a marker for poor prognosis, particularly for ischemic cardiac events.
ProTaper rotary root canal preparation: effects of canal anatomy on final shape analysed by micro CT.

AIM To evaluate the relative performance of ProTaper nickel-titanium (Ni-Ti) instruments shaping root canals of varying preoperative canal geometry. METHODOLOGY Extracted human maxillary molars were scanned, before and after shaping with ProTaper, employing micro computed tomography (muCT) at a resolution of 36 mum. Canals were three-dimensionally reconstructed and evaluated for volume, surface area, 'thickness' (diameter), canal transportation and prepared surface. Based on median canal volume, canals were divided into 'wide' and 'constricted' groups. Comparisons were made between mesiobuccal (mb), distobuccal (db) and palatal (p), as well as 'wide' and 'constricted' canals, using repeated-measures anova and Scheffé posthoc tests. RESULTS Volume and surface area increased significantly and similarly in mb, db and p canals, and gross preparation errors were found infrequently. Root canal diameters, 5-mm coronal to the apex, increased from 0.38 to 0.65 mm, 0.42 to 0.66 mm and 0.57 to 0.79 mm for mb, db and p canals, respectively. Apical canal transportation ranged from 0.02 to 0.40 mm and was independent of canal type; 'wide' canals had a significantly higher (P < 0.05) proportion of unprepared surfaces than 'constricted' canals. CONCLUSIONS Canals in maxillary molars were prepared in vitro using ProTaper instruments without major procedural errors. These instruments may be more effective in shaping narrow canals than wider, immature ones.
Pulmonary hypertension in Switzerland: treatment and clinical course.

BACKGROUND The prognosis of pulmonary hypertension (PH), especially idiopathic pulmonary arterial hypertension (IPAH), has improved during the recent years. The Swiss Registry for PH represents the collaboration of the various centres in Switzerland dealing with PH and serves as an important tool in quality control. The objective of the study was to describe the treatment and clinical course of this orphan disease in Switzerland. METHODS We analyzed data from 222 of 252 adult patients, who were included in the registry between January 1999 and December 2004 and suffered from either PAH, PH associated with lung diseases or chronic thromboembolic PH (CTEPH) with respect to the following data: NYHA class, six-minute walking distance (6-MWD), haemodynamics, treatments and survival. RESULTS If compared with the calculated expected figures the one, two and three year mean survivals in IPAH increased from 67% to 89%, from 55% to 78% and from 46% to 73%, respectively. Most patients (90%) were on oral or inhaled therapy and only 10 patients necessitated lung transplantation. Even though pulmonary endarterectomy (PEA) was performed in only 7 patients during this time, the survival in our CTEPH cohort improved compared with literature data and seems to approach outcomes usually seen after PEA. The 6-MWD increased maximally by 52 m and 59 m in IPAH and CTEPH, respectively, but in the long term returned to or below baseline values, despite the increasing use of multiple specific drugs (overall in 51% of IPAH and 29% of CTEPH). CONCLUSION Our national registry data indicate that the overall survival of IPAH and presumably CTEPH seems to have improved in Switzerland. Although the 6-MWD improved transiently, it decreased in the long term despite specific and increasingly combined drug treatment. Our findings herewith underscore the progressive nature of the diseases and the need for further intense research in the field.
Ballistics and visual targeting in flea-beetles (Alticinae)

The kinematics of jumping was measured in seven species of flea-beetle (Alticinae). The accuracy of two species during targeted jumping was also investigated. Take-off accelerations ranged from 15 to 270 times gravity. Rotational energy accounted for 4­21 % of the total translational energy. Two species were able to control jump direction and landing. When presented with a high-contrast optical grid, Chalcoides aurata exhibited two alternative jump modes. In mode 1 or wingless jumping, the body rotated continuously, the insect rarely landed on its feet and no discrimination was shown between landing on the black or white stripes of the grid. In mode 2 jumping, recruitment of the wings eliminated rotation and virtually ensured a feet-first landing; there was also a significant preference for jumping towards the black stripes. Aphthona atrocaerulea could alter take-off angle in order to strike targets at inclinations of 0­90 ° to the horizontal. Targets consisting of a white illuminated cross on a black background were struck with equal accuracy, regardless of distance (within the normal jumping range). The beetle aimed specifically for the centre of the target and not for the high-contrast boundary. The distribution of hits about the target centre was radially symmetrical. Although take-off was wingless, rotation could be abolished in mid jump, within 10 ms, by extending the wings. This virtually guaranteed a feet-first landing. Targeting accuracy is discussed in the context of biomechanical steering mechanisms and visual control.
Corruption and Entrepreneurship in Emerging Markets

ABSTRACT We applied an institutional perspective lens to examining the relationship between corruption and entrepreneurship. Our results suggest that corruption plays an informal but legitimate institutional channel in facilitating entrepreneurship in sub-national regions with underdeveloped formal institutions. However, we also find the positive relationship between corruption and entrepreneurship is limited, and that high levels of corruption have a negative effect on entrepreneurship. Examining a longitudinal nationwide individual-level survey from China, we find an inverted U relationship between corruption and entrepreneurship; i.e., sub-national corruption at low levels is positively associated with focal regions’ prevalence of entrepreneurship, but prevalence of entrepreneurship is negatively correlated with high levels of corruption. Additionally, we find that sub-national regions with stronger marketization level (e.g., pro-market resource allocation and lower market entry barriers) can offset the diminishing positive effect of corruption. This study theoretically advances the puzzle of mixed findings on the corruption–entrepreneurship relationship by considering the sub-national region differences. We also enrich the understanding of the role of informal institutions on entrepreneurship activities in emerging markets.
Psychological well-being (PWB): a natural life outlook? An Italian twin study on heritability of PWB in young adults

Background To date, the genetic and environmental architecture of the dimensions of psychological well-being (PWB) remains unexplored. Method PWB of 742 twins aged 23–24 years and enrolled in the Italian Twin Registry was assessed with the three-item version of Ryff's Scales of Psychological Well-Being (SPWB). These scales include items for evaluating the PWB dimensions of self-acceptance, positive relations with others, autonomy, environmental mastery, purpose in life, and personal growth. A twin design was used to obtain correlations in the PWB dimensions for monozygotic (MZ) and dizygotic (DZ) twins and to estimate the contribution of genetic and environmental factors to variation and covariation in the dimensions. Results Genetic factors explained moderate to substantial proportions of variance in the six SPWB dimensions, with heritability estimates between 37% and 64%. The estimates of genetic correlations were very high (range 0.77–0.99), indicating that genetic factors that influence the expression of the different dimensions of PWB may be shared to a large extent. Non-shared environmental correlations ranged from substantial to high, with the exception of the correlation between autonomy and the dimensions of purpose in life, self-acceptance and personal growth. Conclusions This study presents a twin analysis of PWB measured by the SPWB dimensions; it was found that both genes and non-shared environment play a role in individual differences. The genetic and non-shared environmental correlations between SPWB dimensions suggest that common underlying genetic and non-shared environmental factors influence the expression of the different facets of PWB.
Spermine inhibits Vibrio cholerae biofilm formation through the NspS–MbaA polyamine signaling system

The aquatic bacterium and human intestinal pathogen, Vibrio cholerae, senses and responds to a variety of environment-specific cues to regulate biofilm formation. Specifically, the polyamines norspermidine and spermidine enhance and repress V. cholerae biofilm formation, respectively. These effects are relevant for understanding V. cholerae pathogenicity and are mediated through the periplasmic binding protein NspS and the transmembrane bis-(3′-5′) cyclic diguanosine monophosphate (c-di-GMP) phosphodiesterase MbaA. However, the levels of spermidine required to inhibit biofilm formation through this pathway are unlikely to be encountered by V. cholerae in aquatic reservoirs or within the human host during infection. We therefore hypothesized that other polyamines in the gastrointestinal tract may control V. cholerae biofilm formation at physiological levels. The tetramine spermine has been reported to be present at nearly 50 μm concentrations in the intestinal lumen. Here, we report that spermine acts as an exogenous cue that inhibits V. cholerae biofilm formation through the NspS–MbaA signaling system. We found that this effect probably occurs through a direct interaction of spermine with NspS, as purified NspS protein could bind spermine in vitro. Spermine also inhibited biofilm formation by altering the transcription of the vps genes involved in biofilm matrix production. Global c-di-GMP levels were unaffected by spermine supplementation, suggesting that biofilm formation may be regulated by variations in local rather than global c-di-GMP pools. Finally, we propose a model illustrating how the NspS–MbaA signaling system may communicate exogenous polyamine content to the cell to control biofilm formation in the aquatic environment and within the human intestine.
Analyzing Incomplete Data Subject to a Threshold using Empirical Likelihood Methods: An Application to a Pneumonia Risk Study in an ICU Setting

Summary The initial detection of ventilator‐associated pneumonia (VAP) for inpatients at an intensive care unit needs composite symptom evaluation using clinical criteria such as the clinical pulmonary infection score (CPIS). When CPIS is above a threshold value, bronchoalveolar lavage (BAL) is performed to confirm the diagnosis by counting actual bacterial pathogens. Thus, CPIS and BAL results are closely related and both are important indicators of pneumonia whereas BAL data are incomplete. To compare the pneumonia risks among treatment groups for such incomplete data, we derive a method that combines nonparametric empirical likelihood ratio techniques with classical testing for parametric models. This technique augments the study power by enabling us to use any observed data. The asymptotic property of the proposed method is investigated theoretically. Monte Carlo simulations confirm both the asymptotic results and good power properties of the proposed method. The method is applied to the actual data obtained in clinical practice settings and compares VAP risks among treatment groups.
The scope of the external return to higher education

This article examines whether the productivity spillovers from a large share of highly educated workers occur within regions, sectors and/or firms. To distinguish between these possibilities, I follow a two-stage procedure to estimate a Mincerian wage equation using matched employer-employee panel data on individual earnings and educational attainment. The results indicate that the scope of higher education spillovers is very limited. Most of the identified spillovers occur within firms, being a factor of 2-3 larger than those operating outside the firm. The spillovers that take place outside the firm are restricted within the own sector and only occur on short distances from the working place. The limited scope confirms the view that higher education spillovers foster aggregate productivity through the exchange of tacit knowledge, which is heavily dependent on face-to-face contact.
The Effect of Interest Rates on Home Buying: Evidence from a Discontinuity in Mortgage Insurance Premiums

We study the effect of interest rates on the housing market by taking advantage of a sudden and unexpected price change in a large government mortgage program. The Federal Housing Administration (FHA) insures most mortgages to lower-downpayment, lower credit score borrowers, including a majority of first-time homebuyers. The FHA charges borrowers an annual mortgage insurance premium (MIP), and in January, 2015 the FHA abruptly reduced the MIP, and thus FHA borrowers’ effective interest rate, by 50 basis points. Using a regression discontinuity design, we find that the MIP reduction increased the number of home purchase originations among the FHA-reliant population by nearly 14 percent. The response to the premium cut was negatively correlated with borrower income, with no observable response among relatively high income borrowers. We trace part of the jump in home buying to the MIP reduction helping ease binding debt payment-to-income ratio limits thus allowing more applications to be approved. Finally, we find no evidence that the MIP reduction increased house prices.
Generative probabilistic models for image retrieval

Searching for information is a recurring problem that almost everyone has faced at some point. Being in a library looking for a book, searching through newspapers and magazines for an old article or searching through emails for an old conversation with a colleague are some examples of the searching activity. These are some of the many situations where someone; the “user”; has some vague idea of the information he is looking for; an “information need”; and is searching through a large number of documents, emails or articles; “information items”; to find the most “relevant” item for his purpose. In this thesis we study the problem of retrieving images from large image archives. We consider two different approaches for image retrieval. The first approach is content based image retrieval where the user is searching images using a query image. The second approach is semantic retrieval where the users expresses his query using keywords. We proposed a unified framework to treat both approaches using generative probabilistic models in order to rank and classify images with respect to user queries. The methodology presented in this Thesis is evaluated on a real image collection and compared against state of the art methods.