Inflation Ratio Research Articles

The effect of governance on public debt: an empirical investigation for the Arabian Gulf countries

PurposeThe question of public debt management for both developed and developing economies has created an enormous amount of political as well as academic interest. The purpose of this paper is to examine how governance affects public debt accumulation in the Arabian Gulf countries during the period between 1996 and 2015 period. The six Worldwide Governance indicators (WGI) (voice and accountability (VAA), political stability and the absence of violence/terrorism, government effectiveness (GEFF), regulatory quality (RQ), rule of law (RL) and control of corruption) were used to measure the quality of governance in these countries. The results show that an increase in every governance indicator except control of corruption leads to a decrease in public debt.Design/methodology/approachThe authors estimate a dynamic specification of debt to GDP ratio to study how governance affects public debt accumulation in the Arabian Gulf countries during the 1996–2015 period. The dependent variable in this study is the ratio of public debt to GDP. This study relies on the six measures of institution’s quality given by the WGI. These variables are the VAA, political stability and absence of violence (PSAV)/terrorism, GEFF, RQ, RL and control of corruption. Additional control variables are also incorporated to account for the omitted variables bias. These include the rate of inflation (Al-Marhubi, 2000) and the independent variable lagged one period. The study of the statistical relationship between institutional quality and public debt allows us to quantify the direct effect of governance on public debt, which is the effect that goes through an increase in spending or a reduction in fiscal revenues and not through a decrease in GDP growth. The econometric estimation is carried out using panel fixed effects and GLS random effects.FindingsThe estimation results confirm the core hypothesis, which considers that the poor governance in a country the higher is the ratio of public debt to GDP, ceteris paribus. Indeed, five of the worldwide Governance Index are negatively correlated with public debt ratio. These indices are GEFF, VAA, PSAV, RQ and RL. Empirical findings for other independent variables are consistent with those of empirical studies in the literature. The coefficient on the independent variable per capita income has the theoretically expected negative sign and it is highly statistically significant, implying that the higher the per capita income in a country, the lower the ratio of public debt. The independent variable government expenditure has the theoretically expected positive sign suggesting that the higher the government expenditure, the higher the ratio of public debt. The education variable has negative but not statistically significant coefficients. The independent variables (inflation, unemployment rate and lag debt ratio) have the expected signs and are highly statistically significant, implying that the higher their value in a country, the higher the ratio of public debt to GDP. Having the theoretically expected effect, the GDP growth variable is negatively correlated with public debt ratio but its coefficients are not statistically significant.Originality/valueAlthough the literature on the damaging effects of poor governance on growth is abundant (Tanzi and Davoodi, 2002; Mauro, 1996; Mo, 2001; Mauro, 1996; Brunetti et al., 1997; Campos et al., 1999; Al-Marhubi, 2000; Depken and Lafountain, 2006; Mauro, 1998), only very recently the relationship between institutional quality and public debt accumulation has been addressed. By reviewing the research on political and institutional determinants of public debt, it was found that there are few studies, which have examined regional differences, and even fewer ones have focused on the countries of the Gulf Cooperation Council (GCC). Therefore, this paper aims to fill the gap by focusing on this economic region. Furthermore, when studying the relationship between the quality of institutions and the accumulation of public debt, existing studies focus only on corruption index and neglect other determinants of governance. Thus, a second contribution of the study is to investigate how institution quality, through the six WGI, affects public debt accumulation. Furthermore, given the recent rise in public debt in GCC countries, an increasingly important question is what policy actions do these countries need to take to ensure that their debt will be sustainable and will not overwhelm their financial system? we can add: while there has been much attention given to the political and economic explanations of public debt accumulation in developing and developed countries on a global scale, scholars so far have not focused on this debate in high income oil producers.

Utilization of unprocessed steel slag as fine aggregate in normal- and high-strength concrete

With the increasing shortage of natural materials, using steel slag instead of natural sand to prepare concrete has become a promising technology. This study aims to investigate the utilization of unprocessed steel slag in normal- and high-strength concrete, focusing on the effects of steel slag as fine aggregate on the compressive behaviour of concrete. Two types of concrete (normal- and high-strength concrete) and eight replacement percentages of fine aggregate by steel slag (0%, 10%, 20%, 30%, 40%, 60%, 80%, and 100%) are used as the test parameters. A series of axial compression tests are conducted on cylinders of fine steel slag concrete (SSC). The influence of the replacement percentage of steel slag on the stress-strain relation, compressive strength, inflation ratio, elastic modulus, and toughness of normal- and high-strength concrete is analysed. Moreover, the failure mechanism of SSC under compression is discussed. The results show that the compressive strength of SSC is not monotonous with increasing steel slag content and that the use of steel slag as fine aggregate in concrete mixes has a positive effect on the energy absorption capacity. SSC with an optimal steel slag content can exhibit better compressive behaviour compared with normal concrete.

Economic life cycle of the bus fleet: a case study

The purpose of the paper is to discuss the application of econometric models to life-cycle cost (LCC) of an urban bus fleet with an emphasis on the maintenance costs. The practical results are compared with theoretical ones, which represent a good maintenance and functioning management. The influence of inflation ratio, as well as the price of fuel in the withdrawal time are evaluated. The paper analyses if there is a variation at the time of the vehicle replacement, obtained from several econometric methods namely the annual uniform income and minimisation of the average total cost with reduction to the present value. It also emphasises an eventual relation between the maintenance policy and the reserve fleet, and the relation between maintenance performance and time replacement of bus fleet. Finally, the paper analyses differences between replacement simulations from theoretical econometric models and the same ones applied to real data.

Inflation, Employment and FDI in Bosnia and Herzegovina

The monetary policy of Bosnia and Herzegovina (hereinafter referred to as BIH) operates under the currency board system, responsible for strengthening the market economy and price stability. On the other hand, the economy of BIH is facing long-term unemployment, unfavorable business environment and feeble competitive position. This discourages economic development. Further retaining the currency board system in BIH attracts great interest. The paper analyzes the relation among inflation, unemployment and foreign direct investment (FDI). Statistical analysis (coefficient of correlation and simple linear regression (period 2004/2014)) indicates that there is no inversion similar to the Phillips curve between inflation and unemployment. Thus, it is implied that BIH renounces employment, aggregate demand and economic growth for the sake of stable prices. Moreover, the ratio of inflation and participation of FDI in GDP is inverse with a negligible correlation. Analyses demonstrate that there is no optimal combination of inflation and unemployment in BIH that would improve business environment and stimulate FDI and aggregate demand. Correlation and regression analyses fail to provide the arguments to statistically challenge the currency board as the monetary system model of BIH.

PENGARUH PRODUK DOMESTIK BRUTO, INFLASI DAN RASIO GINI TERHADAP PENGANGGURAN TERBUKA DI PROVINSI DKI JAKARTA

Gross Regional Domestic Product (GRDP) which provides a comprehensive picture of the economic conditions of a region is indicator for analyzing economic region development. Another indicator that is no less important is inflation as an indicator to see the level of changes in price increases due to an increase in the money supply that causes rising prices. The success of development must also look at the income inequality of its population which is illustrated by this ratio. One of the main regional development goals is to improve the welfare of its people, where to see the level of community welfare, among others, can be seen from the level of unemployment in an area. To that end, in order to get an overview of the effects of GRDP, inflation and the ratio of gini to unemployment in DKI Jakarta for the last ten years (2007-2016), an analysis was carried out using multiple linear regression methods. As a result, together the relationship between GRDP, inflation and the Gini ratio is categorized as "very strong" with a score of 0.936, and has a significant influence on unemployment. Partially, the GRDP gives a significant influence, but inflation and gini ratio do not have a significant influence. GDP, inflation and the Gini ratio together for the last ten years have contributed 81.4% to unemployment in DKI Jakarta, while the remaining 18.6% is influenced by other variables not included in this research model, so for reduce unemployment in DKI Jakarta, programs that are oriented to economic growth, suppressing inflation and decreasing this ratio need to be carried out simultaneously. Keywords: GRDP, inflation, unemployment, DKI Jakarta, GINI ratio

Role of survey response rates on valid inference: an application to HIV prevalence estimates

BackgroundNationally-representative surveys suggest that females have a higher prevalence of HIV than males in most African countries. Unfortunately, these results are made on the basis of surveys with non-ignorable missing data. This study evaluates the impact that differential survey nonresponse rates between males and females can have on the point estimate of the HIV prevalence ratio of these two classifiers.MethodsWe study 29 Demographic and Health Surveys (DHS) from 2001 to 2010. Instead of employing often used multiple imputation models with a Missing at Random assumption that may not hold in this setting, we assess the effect of ignoring the information contained in the missing HIV information for males and females through three proposed statistical measures. These measures can be used in settings where the interest is comparing the prevalence of a disease between two groups. The proposed measures do not utilize parametric models and can be implemented by researchers of any level. They are: (1) an upper bound on the potential bias of the usual practise of using reported HIV prevalence estimates that ignore subjects who have missing HIV outcomes. (2) Plausible range intervals to account for nonresponses, without any additional parametric modeling assumptions. (3) Prevalence ratio inflation factors to correct the point estimate of the HIV prevalence ratio, if estimates of nonresponders’ HIV prevalences were known.ResultsIn 86% of countries, males have higher upper bounds of HIV prevalence than females, this is consonant with males possibly having higher infection rates than females. Additionally, 74% of surveys have a plausible range that crosses 1.0, suggesting a plausible equivalence between male and female HIV prevalences.ConclusionsIt is quite reasonable to conclude that there is so much DHS nonresponse in evaluating the HIV status question, that existing data is plausibly generated by the situation where the virus is equally distributed between the sexes.

Analysis of factors influencing drain amount, time to drain removal, and seroma formation in patients undergoing immediate expander-implant breast reconstruction

Background: Placement of a closed suction drain is a common cause of patient complaints, such as postoperative pain or discomfort following immediate expander-implant breast reconstruction. This study aims to identify factors that affect drainage volume, time to drain removal, and seroma formation.Methods: A retrospective chart review of prospectively collected data was conducted on patients who underwent immediate expander-implant breast reconstructions following nipple-sparing or skin-sparing mastectomy without skin excision (nipple areolar complex excision only) between February 2010 and April 2015. Daily drainage volume was measured until the drain was removed. Eight independent variables, including acellular dermal matrix (ADM) usage and inflation ratio (the rate of initial inflation volume to mastectomy weight) were analysed by univariable and multivariable analyses.Results: A total of 162 breasts in 148 patients were included in this study. The inflation ratio did not influence the drain amount or days to drain removal. Although the use of ADM was significantly associated with increased drainage during the first 5 postoperative days (p = 0.015), it was not significant when adjusted for time. Old age, larger expander size, and larger drain amount on the first postoperative day were predictors for longer days to drain removal (p < 0.001). Old age had a trend toward higher risk of seroma formation that approached statistical significance (p = 0.057).Conclusions: The use of ADM and initial inflation ratio do not influence days to drain removal or seroma formation. A longer period of drain placement is expected when a larger expander is used or in elderly patients.

Efficiency in BRICS banking under data vagueness: A two-stage fuzzy approach

This study analyzes the efficiency levels of the banking industry in the BRICS countries (Brazil, Russia, India, China, and South Africa) from 2010 to 2014, using an integrated two-stage fuzzy approach. Very often the reliability of data collected from BRICS is questionable. In this research, we first use fuzzy TOPSIS to capture vagueness in the relative efficiency of BRICS banking over time. In the second stage, we adopt fuzzy regressions based on different rule-based systems to enhance the power of significant socioeconomic, regulatory, and demographic variables to predict banking efficiency. These variables are previously identified by using bootstrapped truncated regressions with conditional α-levels, as proposed by Wanke, Barros, and Emrouznejad (2015a). The results reveal that efficiency in the banking industry is positively associated with country gross savings and the GINI index ratio, but negatively associated with relatively high inflation ratios. Fuzzy regressions proved far more accurate than bootstrapped truncated regressions with conditional α-levels. We derive policy implications.

Opening pressures and atelectrauma in acute respiratory distress syndrome

Open lung strategy during ARDS aims to decrease the ventilator-induced lung injury by minimizing the atelectrauma and stress/strain maldistribution. We aim to assess how much of the lung is opened and kept open within the limits of mechanical ventilation considered safe (i.e., plateau pressure 30cmH2O, PEEP 15cmH2O). Prospective study from two university hospitals. Thirty-three ARDS patients (5 mild, 10 moderate, 9 severe without extracorporeal support, ECMO, and 9 severe with it) underwent two low-dose end-expiratory CT scans at PEEP 5 and 15cmH2O and four end-inspiratory CT scans (from 19 to 40cmH2O). Recruitment was defined as the fraction of lung tissue which regained inflation. The atelectrauma was estimated as the difference between the intratidal tissue collapse at 5 and 15cmH2O PEEP. Lung ventilation inhomogeneities were estimated as the ratio of inflation between neighboring lung units. The lung tissue which is opened between 30 and 45cmH2O (i.e., always closed at plateau 30cmH2O) was 10±29, 54±86, 162±92, and 185±134g in mild, moderate, and severe ARDS without and with ECMO, respectively (p<0.05 mild versus severe without or with ECMO). The intratidal collapses were similar at PEEP 5 and 15cmH2O (63±26 vs 39±32g in mild ARDS, p=0.23; 92±53 vs 78±142g in moderate ARDS, p=0.76; 110±91 vs 89±93, p=0.57 in severe ARDS without ECMO; 135±100 vs 104±80, p=0.32 in severe ARDS with ECMO). Increasing the applied airway pressure up to 45cmH2O decreased the lung inhomogeneity slightly (but significantly) in mild and moderate ARDS, but not in severe ARDS. Data show that the prerequisites of the open lung strategy are not satisfied using PEEP up to 15cmH2O and plateau pressure up to 30cmH2O. For an effective open lung strategy, higher pressures are required. Therefore, risks of atelectrauma must be weighted versus risks of volutrauma. Clinicaltrials.gov identifier: NCT01670747 ( www.clinicaltrials.gov ).

Primordial fluctuations from inflation in dRGT bimetric theory of gravity

We investigate primordial gravitational waves and curvature perturbations in de Rham-Gabadadze-Tolley (dRGT) bimetric gravity. We evaluate the power-spectra in the leading order in slow roll. Taking into account the decay of massive graviton, we find that the action up to the second order reduces to the Einstein theory with a non-minimally coupled scalar field, which is simplified to a minimally coupled model by conformal transformation. We also find that the tensor to scalar ratio for large field inflation with power law potential is larger than the general relativity counterpart for any choice of parameters in dRGT bimetric gravity. In addition, we confirm that the usual consistency relation holds and we have a steeper spectrum for gravitational waves.

Cognitive ability, social desirability, body mass index and socioeconomic status as correlates of fourth-grade children's dietary-reporting accuracy.

ObjectivesTo investigate the relationship of reporting accuracy in 24-h dietary recalls to child respondent characteristics—cognitive ability, social desirability, body mass index (BMI) percentile, and socioeconomic status (SES).Subjects/MethodsFourth-grade children (mean age 10.1 years) were observed eating two school meals and interviewed about dietary intake for 24-h that included those meals. (Eight multiple-pass interview protocols operationalized the conditions of an experiment that crossed two retention intervals—short and long—with four prompts [ways of eliciting reports in the first pass].) Academic achievement test scores indexed cognitive ability; social desirability was assessed by questionnaire; height and weight were measured to calculate BMI; nutrition-assistance program eligibility information was obtained to index SES. Reported intake was compared to observed intake to calculate measures of reporting accuracy for school meals at the food-item (omission rate; intrusion rate) and energy (correspondence rate; inflation ratio) levels. Complete data were available for 425 of 480 validation-study participants.ResultsControlling for manipulated variables and other measured respondent characteristics, for one or more of the outcome variables, reporting accuracy increased with cognitive ability (omission rate, intrusion rate, correspondence rate, P < .001); decreased with social desirability (correspondence rate, P < .0004); decreased with BMI percentile (correspondence rate, P = .001), and was better by higher than by lower SES children (intrusion rate, P = .001). Some of these effects were moderated by interactions with retention interval and sex.ConclusionsChildren’s dietary-reporting accuracy is systematically related to such respondent characteristics as cognitive ability, social desirability, BMI percentile, and SES.

Accuracy of reported food intake in a sample of 7–10 year-old children in Serbia

ObjectivesChildren's ability to recall and report dietary intake is affected by age and cognitive skills. Dietary intake reporting accuracy in children is associated with age, weight status, cognitive, behavioural, social factors and dietary assessment techniques. This study analysed accuracy of 7–10 year-old children's reported food intake for one day. Study designValidation study. MethodsSample included 94 children aged 7–10 years (median = 9 years) from two elementary schools in a local community in Serbia. ‘My meals for one day’ questionnaire was a combination of 24-h recall and food recognition form. It included recalls for five meals: breakfast at home; snack at home; lunch at home; snack at school and dinner at home. Parental reports were used as reference information about children's food intake for meals obtained at home and observation was used to gain reference information for school meal. Observed and reported amounts were used to calculate omission rate, intrusion rate, corresponding, over-reported and unreported amounts of energy, correspondence rate and inflation ratio. ResultsOverall omission rate (37.5%) was higher than overall intrusion rate (36.7%). The same food item (bread) has been the most often correctly reported and omitted food item for breakfast, lunch and dinner. Snack at school had the greatest mean correspondence rate (79.6%) and snack at home the highest mean inflation ratio (90.7%). ConclusionMost errors in children's recalls were incorrectly reported amounts and not the food items. The questionnaire should be improved to facilitate accurate reports of the amounts.

Children's school-breakfast reports and school-lunch reports (in 24-h dietary recalls): conventional and reporting-error-sensitive measures show inconsistent accuracy results for retention interval and breakfast location.

Validation-study data were analysed to investigate retention interval (RI) and prompt effects on the accuracy of fourth-grade children's reports of school-breakfast and school-lunch (in 24-h recalls), and the accuracy of school-breakfast reports by breakfast location (classroom; cafeteria). Randomly selected fourth-grade children at ten schools in four districts were observed eating school-provided breakfast and lunch, and were interviewed under one of eight conditions created by crossing two RIs ('short'--prior-24-hour recall obtained in the afternoon and 'long'--previous-day recall obtained in the morning) with four prompts ('forward'--distant to recent, 'meal name'--breakfast, etc., 'open'--no instructions, and 'reverse'--recent to distant). Each condition had sixty children (half were girls). Of 480 children, 355 and 409 reported meals satisfying criteria for reports of school-breakfast and school-lunch, respectively. For breakfast and lunch separately, a conventional measure--report rate--and reporting-error-sensitive measures--correspondence rate and inflation ratio--were calculated for energy per meal-reporting child. Correspondence rate and inflation ratio--but not report rate--showed better accuracy for school-breakfast and school-lunch reports with the short RI than with the long RI; this pattern was not found for some prompts for each sex. Correspondence rate and inflation ratio showed better school-breakfast report accuracy for the classroom than for cafeteria location for each prompt, but report rate showed the opposite. For each RI, correspondence rate and inflation ratio showed better accuracy for lunch than for breakfast, but report rate showed the opposite. When choosing RI and prompts for recalls, researchers and practitioners should select a short RI to maximise accuracy. Recommendations for prompt selections are less clear. As report rates distort validation-study accuracy conclusions, reporting-error-sensitive measures are recommended.

Effectiveness of Prompts on Fourth-Grade Children–s Dietary Recall Accuracy Depends on Retention Interval and Varies by Gender1–4

Background: Dietary recall accuracy is related to retention interval (RI) (i.e., time between to-be-reported meals and the interview), and possibly to prompts. To the best of our knowledge, no study has evaluated their combined effect.Objective: The combined influence of RI and prompts on children–s recall accuracy was investigated in this study. Two RIs [short (prior-24-h recall obtained in afternoon) and long (previous-day recall obtained in morning)] were crossed with 4 prompts [forward (distant-to-recent), meal-name (breakfast, lunch, etc.), open (no instructions), and reverse (recent-to-distant)], creating 8 conditions.Methods: Fourth-grade children (n = 480; 50% girls) were randomly selected from consenting children at 10 schools in 4 districts in a southern state during 3 school years (2011–2012, 2012–2013, and 2013–2014). Each child was observed eating school-provided breakfast and lunch, and interviewed one time under 1 of the 8 conditions. Condition assignment was constrained so that each had 60 children (30 girls). Accuracy measures were food-item omission and intrusion rates, and energy correspondence rate and inflation ratio. For each measure, linear models determined effects of RI, prompt, gender, and interactions (2-way, 3-way); race/ethnicity, school year, and district were control variables.Results: RI (P values < 0.015) and prompt (P values < 0.005) were significant for all 4 accuracy measures. RI × prompt (P values < 0.001) was significant for 3 accuracy measures (not intrusion rate). Prompt × gender (P = 0.005) was significant for omission rate. RI × prompt × gender was significant for intrusion rate and inflation ratio (P values < 0.001). For the short vs. long RI across prompts and genders, accuracy was better by 33–50% for each accuracy measure.Conclusions: To obtain the most accurate recalls possible from children, studies should be designed to use a short rather than long RI. Prompts affect children–s recall accuracy, although the effectiveness of different prompts depends on RI and varies by gender: at a short RI, the choice of prompts has little systematic effect on accuracy, whereas at a long RI, reverse prompts may elicit the most accurate recalls.

Favorable Macro Environment: Formula of Investment Activity Growth under the Economic Paradigm Shifted

The article presents the results of study of the impact of the macro environment on investment activities in the Russian Federation for the period 1990-2014. The constructed economic and mathematical models, confirming quite substantial relationship between the dynamics of gross investments in fixed capital and the dynamics of gross profit as a potential source of financial investment in most of sectors of the Russian economy, indicate the need for a qualitative improvement of the macro environment in order to stimulate investment activity in the country during the passage to a new industrial development. The conclusion is that the neo-industrial investments (science-based, high-technology and innovative) act as a key condition for sustainable overcoming of the deindustrialization of production forces, as well as for the passing of the Russian economy to a new development paradigm. The article also makes recommendations regarding the creation of a favorable macro environment for investment activity of economic entities when shifting the paradigm of social and economic development. The recomendations envisage: optimization and reduction of the tax burden; maintenance of macro-economy ratio of profitability, interest rates and inflation; formation of a system of insurance against risk; state support of investments; reducition of corruption in the investment sphere. DOI: 10.5901/mjss.2015.v6n4s4p163

Competition in the banking industry: Empirical evidence from Ghana

Ghana’s banking industry has undergone considerable transformation since 1988 as a result of the gradual but steady implementation of financial service reforms. The main purpose of implementing the financial reforms is to build a competitive and stable banking industry to enhance banks’ efficiency and ultimately economic growth and development. Using annual (panel) data spanning from 2001 to 2010, this study investigates the degree of bank competition and their determinants in Ghana’s banking indusrty using the fixed-effect model and two-step system GMM estimations. The results suggest that Ghana’s banking industry is competitively weak. The findings also indicate that market power persistently exists in Ghana’s banking industry. Furthermore, bank capitalization reduces bank market power and therefore increases bank competition in Ghana. However, there is no indication that bank size, fee income, loan loss provision ratio and rate of inflation have influence on bank competition in Ghana.

Naturally large tensor-to-scalar ratio in inflation

Recently, BICEP2 measurements of the cosmic microwave background (CMB) $B$-mode polarization at degree angular scales has indicated the presence of tensor modes with a high tensor-to-scalar ratio of $r=0.2$ when assuming nearly scale-invariant tensor and scalar spectra, although the signal may be contaminated by dust emission as implied by the recent {\em Planck} polarization data. This result is in conflict with the {\em Planck} best-fit Lambda Cold Dark Model with $r<0.11$. Due to the fact that inflaton has to be interacting with other fields so as to convert its potential energy into radiation to reheat the Universe, the interacting inflaton may result in a suppression of the scalar spectrum at large scales. This suppression has been used to explain the observed low quadrupole in the CMB anisotropy. In this paper, we show that a combination of the tensor modes measured by BICEP2 and the large-scale suppressed scalar modes contributes to the CMB anisotropy in such a way that the resultant CMB anisotropy and polarization power spectra are consistent with both {\em Planck} and BICEP2 data. We also project our findings to cases in which $r$ may become reduced in future CMB polarization measurements.

Ontogeny of swim bladder inflation and caudal fin aspect ratio with reference to vertical distribution in Pacific bluefin tuna Thunnus orientalis larvae

It is necessary to understand the processes involved in sinking death in Pacific bluefin tuna Thunnus orientalis aquaculture in order to develop methods to prevent or minimize this problem. We observed the nighttime vertical distribution of Pacific bluefin tuna in the water column on 2–9 DAH and the morphological characteristics of the larvae, in order to clarify the processes involved in sinking death. A cuboid tank (height 300 cm) was used to measure vertical distribution. The number of larvae was counted in each of 4 regions in the observation tank: upper layer (water depth 0–100 cm), middle layer (100–200 cm), lower layer (200–300 cm), and bottom area. The distribution of larvae in these regions at 4 days after hatching was polarized to the upper layer and bottom area. Individuals with inflated swim bladders were observed in the upper layer 3 days after hatching. No larvae with inflated swim bladders were observed in the bottom area on any day after hatching. Total body length and caudal fin aspect ratio of larvae with both inflated and un-inflated swim bladders were greater in the upper layer than those of larvae in the bottom area. Larvae with un-inflated swim bladders that failed to develop sufficiently for swimming sank to the tank bottom and died. Swim bladder development and caudal fin swimming ability are strongly related to sinking death.

Estimating influence of cofragmentation on peptide quantification and identification in iTRAQ experiments by simulating multiplexed spectra.

Isobaric tag-based quantification such as iTRAQ and TMT is a promising approach to mass spectrometry-based quantification in proteomics as it provides wide proteome coverage with greatly increased experimental throughput. However, it is known to suffer from inaccurate quantification and identification of a target peptide due to cofragmentation of multiple peptides, which likely leads to under-estimation of differentially expressed peptides (DEPs). A simple method of filtering out cofragmented spectra with less than 100% precursor isolation purity (PIP) would decrease the coverage of iTRAQ/TMT experiments. In order to estimate the impact of cofragmentation on quantification and identification of iTRAQ-labeled peptide samples, we generated multiplexed spectra with varying degrees of PIP by mixing the two MS/MS spectra of 100% PIP obtained in global proteome profiling experiments on gastric tumor-normal tissue pair proteomes labeled by 4-plex iTRAQ. Despite cofragmentation, the simulation experiments showed that more than 99% of multiplexed spectra with PIP greater than 80% were correctly identified by three different database search engines-MODa, MS-GF+, and Proteome Discoverer. Using the multiplexed spectra that have been correctly identified, we estimated the effect of cofragmentation on peptide quantification. In 74% of the multiplexed spectra, however, the cancer-to-normal expression ratio was compressed, and a fair number of spectra showed the "ratio inflation" phenomenon. On the basis of the estimated distribution of distortions on quantification, we were able to calculate cutoff values for DEP detection from cofragmented spectra, which were corrected according to a specific PIP and probability of type I (or type II) error. When we applied these corrected cutoff values to real cofragmented spectra with PIP larger than or equal to 70%, we were able to identify reliable DEPs by removing about 25% of DEPs, which are highly likely to be false positives. Our experimental results provide useful insight into the effect of cofragmentation on isobaric tag-based quantification methods. The simulation procedure as well as the corrected cutoff calculation method could be adopted for quantifying the effect of cofragmentation and reducing false positives (or false negatives) in the DEP identification with general quantification experiments based on isobaric labeling techniques.

Upper bound on the tensor-to-scalar ratio in GUT-scale supersymmetric hybrid inflation

We explore the upper bound on the tensor-to-scalar ratio r in supersymmetric (F-term) hybrid inflation models with the gauge symmetry breaking scale set equal to the value 2.86⋅1016 GeV, as dictated by the unification of the MSSM gauge couplings. We employ a unique renormalizable superpotential and a quasi-canonical Kähler potential, and the scalar spectral index ns is required to lie within the two-sigma interval from the central value found by the Planck satellite. In a sizable region of the parameter space the potential along the inflationary trajectory is a monotonically increasing function of the inflaton, and for this case, r≲2.9⋅10−4, while the spectral index running, |dns/dln⁡k|, can be as large as 0.01. Ignoring higher order terms which ensure the boundedness of the potential for large values of the inflaton, the upper bound on r is significantly larger, of order 0.01, for subplanckian values of the inflaton, and |dns/dln⁡k|≃0.006.