Miracle-dz/UniFAR-FTUs huggingface dataset:
Long-term effect of carbodiimide on dentin matrix and resin-dentin bonds.

OBJECTIVES To characterize the interaction of 1-Ethyl-3-[3-dimethylaminopropyl] carbodiimide Hydrochloride (EDC) with dentin matrix and its effect on the resin-dentin bond. METHODS Changes to the stiffness of demineralized dentin fragments treated with EDC/N-hydroxysuccinimide (NHS) in different solutions were evaluated at different time points. The resistance against enzymatic degradation was indirectly evaluated by ultimate tensile strength (UTS) test of demineralized dentin treated or not with EDC/NHS and subjected to collagenase digestion. Short- and long-term evaluations of the strength of resin-dentin interfaces treated with EDC/NHS for 1 h were performed using microtensile bond strength (microTBS) test. All data (MPa) were individually analyzed using ANOVA and Tukey HSD tests (alpha = 0.05). RESULTS The different exposure times significantly increased the stiffness of dentin (p < 0.0001, control-5.15 and EDC/NHS-29.50), while no differences were observed among the different solutions of EDC/NHS (p = 0.063). Collagenase challenge did not affect the UTS values of EDC/NHS group (6.08) (p > 0.05), while complete degradation was observed for the control group (p = 0.0008, control-20.84 and EDC/NHS-43.15). EDC/NHS treatment did not significantly increase resin-dentin muTBS, but the values remained stable after 12 months water storage (p < 0.05). CONCLUSIONS Biomimetic use of EDC/NHS to induce exogenous collagen cross-links resulted in increased mechanical properties and stability of dentin matrix and dentin-resin interfaces.
On Political Regime Changes in Arab Countries

We develop a dynamic game to provide with a theory of Arab spring-type events. We consider two interacting groups, the elite vs the citizens, two political regimes, dictatorship vs a freer regime, the possibility to switch from the first to the second regime as a consequence of a revolution, and finally the opportunity, for the elite, to affect the citizens' decision through concession and/or repression strategies. In this framework, we provide a full characterization of the equilibrium of the political regime switching game. First, we emphasize the role of the direct switching cost of a revolution (for the citizens) and of the elite's self-preservation options. Under the concession strategy, when the switching cost is low, the elite can't avoid the political regime change. She optimally adapts to the overthrow of their political power by setting the rate of redistribution to the highest possible level, thereby extending the period during which she has full control on resources. This surprising result actually illustrates the role of the timing of events in these situations of interaction between the ruling elite and the people. When the direct switching is high, the elite can ultimately select the equilibrium outcome and adopts the opposite strategy, i.e. she chooses the lowest level of redistribution that allows her to stay in power forever. The same kind of results are obtained when the elite relies on repression to keep the citizens under control. Next, the equilibrium properties under a mix of repression and redistribution are analyzed. It is shown that in situations where neither repression (only) nor redistribution (only) protect the elite against the uprising of citizens, a subtle mixture of the two instruments is sufficient to make the dictatorship permanent. Based on our theoretical results, we finally examine the reason for such a large variety of decisions and outcomes during the Arab Spring events.
Fracture strength of teeth with flared root canals restored with glass fibre posts.

OBJECTIVE To investigate the fracture strength and pattern of failure of teeth with weakened roots reconstructed by different procedures. METHODS In an in vitro study root posts were placed in 50 endodontically treated canines, divided into 5 groups (n=10) as follows: cast metallic post; glass fibre post with smaller diameter than the root canal; glass fibre post with smaller diameter than the root canal + glass fibre strips; glass fibre post with smaller diameter than the root canal + accessory glass fibre posts; anatomical post (glass fibre post with smaller diameter than the root canal, relined with low viscosity composite resin). Posts were luted with resin cement and the coronal portion of posts was constructed with composite resin. Metallic crowns were cemented on the posts. Specimens were submitted to compressive load in a universal testing machine. Fracture strength values of each group were compared. RESULTS Fracture strength values were for Groups 1-5 respectively: 1087.06; 745.69; 775.41; 920.64; 876.12kgf, with significant differences between Groups 1 and 2 and between Groups 1 and 3 (p<0.05). Observed patterns of fracture were: Group 1 - 100% of roots fractured; Groups 2 and 4 - variable fracture modes; Group 3 - 60% of fractures occurred in the cervical root third; Group 5 - 50% of failures occurred in the coronal portion of the post. CONCLUSIONS The fracture strength of teeth with cast metallic posts, teeth with anatomical posts or teeth with glass fibre posts combined with accessory posts was similar. All teeth restored with cast metallic posts presented fractures and were unfavourable to maintenance of the remaining tooth structure. Teeth with fibre posts (Groups 2 to 5) presented variable fracture modes; however, the maximum percentage of unfavourable fractures was 30%.
Assets, Poverty, and Children

The Fedele F. and Iris M. Fauri Lecture is presented annually in recognition of former University of Michigan Vice President and School of Social Work Dean Fedele F. Fauri and his wife, Iris. Dean Fauri's leadership in the field of child welfare spanned nearly 50 years, with much of the current social welfare legislation at both state and federal levels being a product of Dean Fauri's activities, first as director of the Michigan Department of Social Services, and then during his years in Washington, DC, where he held numerous leadership positions. His accomplishments in child welfare and social work education brought national and international acclaim to Dean Fauri, the School of Social Work, and the University of Michigan. This lecture series is funded by gifts from alumni, faculty, and friends, and is intended to serve as a forum for discussing ideas and proposals to enhance the well-being of young people.
HETEROGENEOUS FIRMS AND THE ORGANIZATION OF PRODUCTION

Firms in the same industry exhibit systematic differences in the organization of production and the structure of employment. Entrepreneurial ability is the specific scarce input that limits the size of a firm. This input must be allocated to two activities, coordinating production and monitoring workers. Able entrepreneurs can convert calendar time into larger supplies of coordinating effort that enable them to assemble large firms. Greater ability implies a higher shadow price of time which increases the implicit costs of monitoring. A dispersion of entrepreneurial abilities generates an equilibrium size distribution of firms. Differences in monitoring costs affect the choice of worker productivities, the design of products, and the organization of production. The monitoring cost hypothesis advanced in this paper goes a long way in explaining the equilibrium of an industry containing heterogeneous firms that differ in size and behavior.
Net carbon storage measured in a mowed and grazed temperate sown grassland shows potential for carbon sequestration under grazed system

Background: Managed temperate grassland has the potential to sequester carbon if management practices are improved. In this study, CO2 flux was measured by the eddy covariance technique in two identical temperate sown grasslands under different managements, viz. mowing and grazing, to estimate and compare net carbon storage under both the management systems. Results: In both mowing and grazing systems, the averaged annual gross plant productivity, ecosystem respiration and net ecosystem exchange were –1720 and –1741, 1244 and 1510, and –476 and –231 g C m–2 year–1, respectively. Although the management practices did not significantly influence gross plant productivity (p > 0.05), grazing system increased Reco significantly by 21% (p < 0.05) but reduced net ecosystem exchange by 52% (p < 0.05) compared to mowing system. However, averaged annual net carbon storage were 23 and 141 g C m–2 year–1 under mowing and grazing, respectively. Conclusion: The results indicate that temperate sown grassland has the potential to sequester carbon under grazing.
Humboldt and the economists on natural resources, institutions and underdevelopment (1752 to 1859)

Abstract The article discusses how early economists, sometimes informed by the pioneer report on a Latin American country (Mexico) by the geographer A. von Humboldt, interpreted the connections between natural resources, institutions and growth. The paradox of a negative relation between natural wealth and growth was elaborated, before Humboldt,by Hume. Humboldt's account of the high degree of income inequality in Mexico caught Malthus's attention, who turned it into a key element of his anti-Ricardo view that the fertility of soil may be associated with poor growth if there is a lack of effective demand. Cairnes claimed that the structural impact of a natural resource boom on the rest of the economy is compatible with the comparative-advantage framework. J.S. Mill articulated the potential perverse effects of natural wealth on effort supply and weak institutions, a theme conspicuous in the modem literature about the “natural resource curse”.
Reporting and Interpreting Effect Size in Quantitative Agricultural Education Research.

The Journal of Agricultural Education (JAE) requires authors to follow the guidelines stated in the Publication Manual of the American Psychological Association [APA] (2009) in preparing research manuscripts, and to utilize accepted research and statistical methods in conducting quantitative research studies. The APA recommends the reporting of effect sizes in quantitative research, when appropriate. JAE now requires the reporting of effect size when reporting statistical significance in quantitative manuscripts. The purposes of this manuscript are to describe the research foundation supporting the reporting of effect size in quantitative research and to provide examples of how to calculate effect size for some of the most common statistical analyses utilized in agricultural education research. Recommendations for appropriate effect size measures and interpretation are included. The assumptions and limitations inherent in the reporting of effect size in research are also incorporated.
What Do We Really Know about Wages? The Importance of Nonreporting and Census Imputation

In the most frequently used microdata sets, over a quarter of all respondents now refuse to answer some questions about their incomes. The Census Bureau has dealt with this problem, which has been increasing in severity over time, by imputing incomes of non-respondents. Their imputation procedure, called the "hot deck," essentially matches nonrespondents with demographically similar donors. In this paper we evaluate the census imputation methodology and raise some questions. First, the census procedure is tied to commonality of events in the population rather than the more appropriate informational content of regressors. Clearly, the census procedure severely understates income in certain occupations. Because it is based on the apparently invalid assumption that income does not affect reporting propensities, it most likely understates average incomes as well.
The provision of human resources and employment advice to small and medium-sized enterprises: The role of small and medium-sized practices of accountants

Small and medium-sized practices (SMPs) are often identified as a main provider of human resources and employment advice to small and medium-sized enterprises (SMEs), but little is known about the nature of this involvement. This article explores this gap in knowledge. It examines the type of support provided and resources used by SMPs and how this support role sits alongside core SMP competencies. Nineteen interviews were carried out. The study found an emphasis upon employment procedures and contracts in the support given. The support offered and the resources used were related to the size of SMP. The trust established during the provision of traditional accountancy services was the main reason that SMEs approached their accountant in search of human resources and employment support. The article provides an important insight into understanding how SMEs are supported in this area and indicates several areas where further research is required.
The Equal Pay Act as an Experiment to Test Theories of the Labour Market

The UK Equal Pay Act of 1970 resulted in a large rise in the relative earnings of women in the early 1970s. As this change (unlike most wage changes) was largely exogenous to employers one can think of this episode as an experiment for testing different theories of the labour market. Hence, study of the effects of the Equal Pay Act should be given considerable weight and is likely to have wider implications about the operation of labour markets. Most models of the labour market used by economists assume that employment is demand-determined at least after a large positive shock to the wage. The models would predict that female relative employment should have fallen after the introduction of the Equal Pay Act. Yet, it is hard to find evidence of this. This paper argues that female employment did not fall because the female labour market is, in part monopsonistic.
Mercury in rocks and minerals of the Skaergaard intrusion, East Greenland

Summary Mercury has been determined by radiochemical neutron-activation analysis in nineteen representative rocks from the Skaergaard intrusion and in the separated cumulus minerals of five. The chilled marginal gabbro contains 0.23 ppm Hg, values in the Layered Series rocks ranging from 0.07 to 0.34 ppm, in one exceptional case reaching 1.23 ppm Hg. There is a tendency for mercury to be more abundant in leucocratic than in average or melanocratic rocks at a similar horizon. Somewhat higher levels of mercury are found in the granophyric rocks at the top of the intrusion. Apart from a weak and sporadic tendency to be preferentially enriched in plagioclase, the distribution of mercury between the various cumulus phases is fairly uniform and it is thought to occur as uncharged atoms mainly occupying spaces resulting from lattice defects and imperfections rather than in specific structural sites. The distribution pattern of mercury in the intrusion appears to be determined by its high volatility and chemical inertness; no real evidence of any chalcophile character is observed.
Reliability of four different computerized cephalometric analysis programs: a methodological error.

Sir, We were interested to read the paper by Erkan and Gurel published in the June 2012 issue of Eur J Orthod. The authors aimed to compare the traditional method of manual cephalometric tracing with four different computerized tracing programs (Dolphin Imaging, Vistadent, Nemoceph and Quick Ceph). They used multivariate analysis of variance and Box’s and Levene’s tests, showing no statistically significant difference between manual tracing and the computerized tracing programs (Erkan et al., 2012). The authors pointed out in their conclusions that the measurements obtained with the cephalometric analysis programs used in the study were reliable. However, they did not use any of the commonly used statistical tests (Intraclass correlation coefficient ICC or weighted kappa) to assess the reliability (Jeckel et al., 2007; Szklo and Nieto, 2007; Rothman et al., 2008). Therefore, we would like to point out that this conclusion may be misleading.
Health-related quality of life predicts outcomes but is not affected by peritoneal clearance: The ADEMEX trial.

BACKGROUND We hypothesized that increasing small solute clearance in peritoneal dialysis (PD) would lead to improvements in patient health-related quality of life (HRQOL). METHODS Patients were randomized to a control group [standard 4 x 2 L continuous ambulatory peritoneal dialysis (CAPD)] and an intervention group (CAPD with a target creatinine clearance >/=60 L/week/1.73 m(2)). The Kidney Disease Quality of Life Short Form was obtained at baseline and at 6, 12, and 24 months. Physical (PCS), mental (MCS), and kidney disease component summary (KDCS) scores were computed. RESULTS The two groups were comparable at baseline with respect to HRQOL. Baseline variables highly predictive of better QOL included absence of diabetes, younger age, higher starting GFR, and serum albumin. Baseline values of QOL were highly predictive of survival and hospitalizations. An unadjusted comparison revealed that patients in the intervention group had significantly higher PCS and KDCS scores at six months. However, there were no significant differences between the intervention and control patients at 12 or 24 months. When similar analyses were carried out adjusting for different patterns of patient dropout, there were no significant differences between the two groups at any time point in terms of PCS, MCS, and KDCS scores. CONCLUSION We found no evidence of a long-term benefit in HRQOL of CAPD patients by increasing peritoneal small-solute clearances when HRQOL parameters were adjusted for patient dropout. Measures of HRQOL have a significant predictive value for patient survival and hospitalizations.
Identification of Native Atrial G-protein-regulated Inwardly Rectifying K+ (GIRK4) Channel Homomultimers*

G-protein-regulated inwardly rectifying K+ (GIRK) channels play critical inhibitory roles throughout the nervous system, heart, and pancreas. They are believed to be heterotetramers consisting of GIRK1 (Kir3.1) and either GIRK2 (Kir3.2), GIRK3 (Kir3.3), or GIRK4 (Kir3.4) subunits. The GIRK1 subunit is hypothesized to be critical to form GIRK channels with normal channel kinetics based on heterologous expression studies. However, GIRK2 and GIRK3 proteins are present in areas of the brain where no GIRK1 has been detected. Here we demonstrate that GIRK tetramers lacking GIRK1 can be purified from bovine heart atria. We have found that only half of GIRK4 is purified as the GIRK1-GIRK4 heterotetramer, whereas the remaining GIRK4 forms a high molecular weight, SDS-resistant complex that does not contain GIRK1. These GIRK4 complexes, most likely GIRK4 homotetramers, were previously not seen because of their aberrant migration on SDS-polyacrylamide gels. We propose that all of GIRK1 and half of GIRK4 proteins in atria combine to form the heterotetramer IKACh, whereas the remaining GIRK4 forms a novel tetrameric complex. GIRK4 homotetramers form channels with unusual single channel behavior, and their contribution to native currents requires further investigation.
A decentralized adaptive learning scheme for adaptive OFDM

Orthogonal Frequency Division Multiplex (OFDM) technique has been successfully deployed in indoor wireless LAN and outdoor broadcasting applications. It is well-known that under a frequency-selective fading channel the resultant sub-channel frequency functions are frequency-variant and may also be time-variant. Hence adaptive modulation may be appropriately applied to improve the error performance and data throughput in an OFDM modem by assigning different modulation and coding schemes to different sub-carriers. One fundamental issue in deploying adaptive modulation is to determine what modulation and coding scheme to use according to the sub-channel SNR. Virtually all past investigations were either based on heuristic methods or analytical means. This paper proposes a novel decentralized adaptive learning scheme that is capable of dynamically adjusting the switching thresholds to improve or maximize the data throughput.
Predictive analysis of factors associated with percutaneous stone surgery outcomes.

INTRODUCTION The aim of this study is to identify surgical, patient- and stone-related factors predictive of clinical success and complications after percutaneous nephrolithotomy (PCNL). MATERIALS AND METHODS We prospectively studied 100 consecutive PCNL procedures. Univariate and multiple regression models were used in order to identify which variables could act as independent predictors of PCNL outcomes. Success was defined as complete absence of fragments in a non-contrast CT. The Clavien-modified grading system was used to classify the complications. RESULTS Univariate analysis showed that patients rendered stone-free had a significantly lower stone burden, shorter operating times, single stones and non-struvite composed calculi. Patient age, nephrostomy tract dilation with high pressure balloon and a stone composition different to struvite behaved as significant protective factors for complications. Logistic regression models revealed that the main independent prognostic factor for success was stone surface (OR = 0.997 per mm2, p = 0.000), followed by multiple stones (OR = 0.203, p = 0.050). On the other hand, struvite composition (OR = 5.911, p = 0.028) was an independent predictor for the development of complications, whilst age (OR = 0.936, p = 0.012) and high pressure balloon dilation (OR = 0.041, p = 0.007) were rendered independent protective variables. CONCLUSIONS Stone burden and multiple calculi in the kidney affect the immediate stone-free rate, whilst Amplatz dilation, struvite stones and young patients lead to a higher incidence of postoperative complications. This information can be very useful for patient counseling, regarding percutaneous kidney stone management.
Sudden Changes in Volatility in European Stock Markets

The question of volatility dynamics has always been the motivation of many researchers in the field of finance with objectives to ensure economic stability and to obtain higher rates of return for investors by portfolio diversification. Consequently, to financial crisis streaming, in the last few decades, a large literature has been focused on studying volatility. Hamao and al. (1991) found evidence of significant price-volatility spill over from US to London and Tokyo, and from London to Tokyo stock markets. Edwards and Naim (1998) observed a new style 'Tequila Effect' of economic crises in Latin America. A similar crisis emerged, at the end of 1997, in Thailand which was far more severe and engulfed far more countries than its predecessor. Itâ€™s bad character has been manifested by its contagion on whole region, for that reason it has been called Asian Crisis. The emergence of East Asian currency crisis in 1997 raised doubt about the lessons learned from Mexico by national and international policy makers, and economic analysts (Edwards & Naim, 1998). Then, again in 2007, the world witnessed the worst crisis in history after the Great Depression of 1929. The crisis appeared in U.S.A due to a complicated interaction of different variables, consisting principally on: 1) lower interest rates, 2) abundance of mortgage loans, 3) weak or no controls at an institutional level and an authoritative level, 4) and the use of securitization. In all the cases mentioned above, we observe lower rates of return, higher volatility, and the propagation of crisis to other stock markets, around the world, during the periods of turbulence.