Three Essays on Population and Historical Legacies: Fertility, Income Inequality and Natural Resources

This dissertation provides three essays on population dynamics from the perspective of historical legacies. The objective is to study how some current population dynamics can be influenced by past events, some of them from a very long-term perspective. The dominant theories and empirical work on population dynamics usually consider current or proximate determinants generally observed from the 20th century onwards. However, there are certain deeper determinants, rooted in history, that could have a powerful long-term influence. The first essay studies the global convergence of fertility. The fertility transition idea is traditionally linked to the global convergence of fertility towards a single equilibrium. In this essay I use a recently developed methodological approach that allows for multiple equilibrium analysis and club identification. It is used data on 190 countries and territories, over a period from 1960 to 2019. The findings in this essay do not support global fertility convergence. Instead, a number of ‘convergence clubs’ emerges from the data. These findings are discussed in the light of various demographic theories, proposing that fertility trends in contemporary societies cannot be understood without taking into account the interplay between continuities and discontinuities rooted of historical legacies. The second essay studies the link between population, extractive institutions, and income inequality for a particular historical period, from which long-term legacies could have emerged. Inequality in Latin America has been large, widespread and persistent. For some scholars, its origin dates back to the colonial period, when Europeans established extractive institutions that have lasted until the present. However, the analysis provided in this essay suggests that income inequality was already very high in the days of the Aztec Empire, so its roots lie in pre-Hispanic institutions. In 2021, it will be five hundred years since Tenochtitlan fell by the Spanish troops in alliance with several peoples who rose up against the Aztec Empire. However, little is known about the conditions of inequality and extraction prior to the arrival of Europeans. Indeed, such conditions might explain the imperial fall. It is analyzed income inequality in the 38 provinces of the Aztec Empire, showing how highly extractive conditions explain the ease with which the Spaniards promoted alliances with certain indigenous peoples to defeat the Aztecs. The same previous extractive conditions may have made it easier for Europeans to adapt the Aztec institutions for their own benefit during the early colonial period. It is concluded that colonialism in Latin America did not create economic inequality, it only exacerbated it. The last essay explores the link between current population dynamics and the environment given by the presence of natural resources from a very long-term perspective. The influential literature on the “curse of natural resources” highlights that resource-rich countries, under certain circumstances, have poorer economic and political outcomes than other countries. The third essay proposes that the presence of non-renewable natural resources also has important implications and long-term effects for fertility and other social dynamics related to family change. In a country-level analysis, this work first documents how the presence of natural resources is highly associated with higher fertility rates across the world. Second, the long-term effects and persistence of this “social curse” are highlighted, by providing evidence at the subnational level that the presence of historic coal mines, dating back to the Industrial Revolution in Europe, can be influencing on current fertility behaviors and other outcomes that are determinants of social change

Communication for Expressivists

How can expressivists make sense of the practice of communication? If communication is not a joint enterprise aimed at sharing information about the world, why do we engage in communication the way we do? Call this the problem of communication. Starting from basic assumptions about the rationality of speakers and the nature of assertion, we argue that speakers engaging in conversation about normative matters must presuppose that there is a unique normative standard on which the attitudes of conversational participants ought to converge. This gives the beginning of a solution to the problem of communication on behalf of expressivists

Policy and performance in customs: Evaluating the trade facilitation agreement

This is the author accepted manuscript. The final version is available from Wiley via the DOI in this record.This paper links cross‐country variation in trade facilitation policies to prominent indicators of national customs and logistics performance. We test the hypotheses that the policy data explain variation in the performance indicators, independent of other country characteristics that are plausibly exogenous to changes in trade facilitation policies. We use a LASSO procedure to choose among the many potential explanatory variables in the model. In general we find that country characteristics related to geography, income, and the general quality of governance better explain cross‐country variation in customs and logistics performance than do the measures of trade facilitation policy.Government of SwedenGovernment of NorwayGovernment of the United Kingdo

The Luminosity Function Evolution of Soft X--ray selected AGN in the RIXOS survey

A sample of 198 soft X--ray selected active galactic nuclei (AGN) from the ROSAT International X--ray Optical Survey (RIXOS), is used to investigate the X--ray luminosity function and its evolution. RIXOS, with a flux limit of 3E-14 erg s-1 cm-2 (0.5 to 2.0 keV), samples a broad range in redshift over 20 deg^2 of sky, and is almost completely identified; it is used in combination with the Einstein Extended Medium Sensitivity Survey (EMSS), to give a total sample of over 600 AGN. We find the evolution of AGN with redshift to be consistent with pure luminosity evolution (PLE) models in which the rate of evolution slows markedly or stops at high redshifts z>1.8. We find that this result is not affected by the inclusion, or exclusion, of narrow emission line galaxies at low redshift in the RIXOS and EMSS samples, and is insensitive to uncertainties in the conversion between flux values measured with ROSAT and Einstein. We confirm, using a model independent Ve/Va test, that our survey is consistent with no evolution at high redshifts.Comment: 10 pages, LaTeX file, PS figures and mn.sty. Accepted in MNRA

Application of temperature and ultrasound as corrective measures to decrease the adhesiveness in dry-cured ham. Influence on free amino acid and volatile compound profile

The impact of low temperature treatment and its combination with ultrasound has been evaluated in order to correct texture defects in dry-cured hams. A total of 26 dry-cured hams, classified as high proteolysis index (PI>36%), were used. From these hams, ten slices from each ham sample were cut, vacuum packed and submitted to three different treatments: control (without treatment), conventional thermal treatments (CV) and thermal treatment assisted by power ultrasound (US). The impact of these treatments on instrumental adhesiveness, free amino acid and volatile compounds profile were assessed. Statistical analysis showed that both US and CV treatments, significantly (P < .001) decreased the instrumental adhesiveness of dry-cured hams from 85.27 g for CO to 40.59 and 38.68 g for US and CV groups, respectively. The total free amino acid content was significantly (P < .001) affected by both treatments, presenting higher values the samples from the US group (6691.5 vs. 6067.5 vs. 5278.2 mg/100 g dry matter for US, CV and CO groups, respectively). No significant differences were observed between US and CV treatments. All the individual free amino acids were influenced by ultrasound and temperature treatments, showing the highest content in sliced dry-cured ham submitted to ultrasounds at 50 °C, except for isoleucine which presented the highest level in samples from CV group. Similarly, significant differences (P < .05) were also detected in the total volatile compound content between CO and US groups, with a higher concentration in the CO batch (56,662.84 AU × 103/g of dry-cured ham) than in the US treatment (45,848.47 AU × 103/g of dry-cured ham), being the values in the CV treatment intermediate (48,497.25 AU × 103/g of dry-cured ham). Aldehydes, ethers and esters, carboxylic acids and sulphur compounds were more abundant in the CO group, while CV group showed higher concentrations of ketones, alcohols and nitrogen compounds.info:eu-repo/semantics/acceptedVersio

Application of temperature and ultrasound as corrective measures to decrease the adhesiveness in dry-cured ham. Influence on free amino acid and volatile compound profile

[EN] The impact of low temperattire treatment and its combination with ultrasound has been evaluated in order to correct texture defects in dry-cured hams. A total of 26 dry-cured hams, classified as high proteolysis index (PI > 36%), were used. From these hams, ten slices from each ham sample were cut, vacuum packed and submitted to three different treatments: control (without treatment), conventional thermal treatments (CV) and thermal treatment assisted by power ultrasound (US). The impact of these treatments on instrumental adhesiveness, free amino acid and volatile compounds profile were assessed. Statistical analysis showed that both US and CV treatments, significantly (P<.001) decreased the instrumental adhesiveness of dry-cured hams from 85.27 g for CO to 40.59 and 38.68 g for US and CV groups, respectively. The total free amino acid content was significantly (P<.001) affected by both treatments, presenting higher values the samples from the US group (6691.5 vs. 6067.5 vs. 5278.2 mg/100 g dry matter for US, CV and CO groups, respectively). No significant differences were observed between US and CV treatments. All the individual free amino acids were influenced by ultrasound and temperature treatments, showing the highest content in sliced dry-cured ham submitted to ultrasounds at 50 degrees C, except for isoleucine which presented the highest level in samples from CV group. Similarly, significant differences (P<.05) were also detected in the total volatile compound content between CO and US groups, with a higher concentration in the CO batch (56,662.84 AU x 10(3)/g of dry-cured ham) than in the US treatment (45,848.47 AU x 10(3)/g of dry-cured ham), being the values in the CV treatment intermediate (48,497.25 AU x 10(3)/g of dry-cured ham). Aldehydes, ethers and esters, carboxylic acids and sulphur compounds were more abundant in the CO group, while CV group showed higher concentrations of ketones, alcohols and nitrogen compounds.This research was supported by Grant RTA 2013-00030-CO3-03 from INIA (Spain). Acknowledgements to INIA for granting Cristina Perez Santaescolastica with a predoctoral scholarship (grant number CPD2015-0212). Jose M. Lorenzo is member of the MARCARNE network, funded by CYTED (ref. 116RT0503).Pérez-Santaescolástica, C.; Carballo, J.; Fulladosa, E.; Garcia-Perez, J.; Benedito Fort, JJ.; Lorenzo, J. (2018). Application of temperature and ultrasound as corrective measures to decrease the adhesiveness in dry-cured ham. Influence on free amino acid and volatile compound profile. Food Research International. 114:140-150. https://doi.org/10.1016/j.foodres.2018.08.006S14015011

Effect of proteolysis index level on instrumental adhesiveness, free amino acids content and volatile compounds profile of dry-cured ham

[EN] Defective textures in dry-cured ham are a common problem that causes important economic losses in the ham industry. An increase of proteolysis during the dry-cured ham processing may lead to high adhesiveness and consumer rejection of the product. Therefore, the influence of proteolysis index (PI) on instrumental adhesiveness, free amino acids and volatile profile of dry-cured ham was assessed. Two hundred Spanish dry-cured ham units were firstly classified according to their PI: low PI ( 36%). Instrumental adhesiveness was affected by PI, showing the lowest values in the batch with low PI. Significant differences (P < 0.05) among groups were found in six amino acids: serine, taurine, cysteine, methionine, isoleucine and leucine. The content of leucine, serine, methionine, and isoleucine significantly (P < 0.05) increased as the proteolysis index rose. However, taurine and cysteine content showed an opposite behaviour, reaching the highest values in the dry-cured hams with low PI. Significant differences (P < 0.001) in the total content of volatile compounds among ham groups were observed, with the highest concentration in the batch with low PI, and decreasing the concentration as the PI increased. Regarding the different chemical families of volatiles, the hydrocarbons (the main family), alcohols, aldehydes, ketones and acids were more abundant in the hams showing the lowest PI. Esters did not show significant differences among the three batches of hams studied. The present study demonstrated that, apart from the effect on the adhesiveness, an excessive proteolysis seems to be associated with negative effects on the taste and aroma of the dry-cured ham.This research was supported by Grant RTA 2013-00030-CO3-03 from INIA (Spain). Acknowledgements to INIA for granting Cristina Perez Santaescolastica with a predoctoral scholarship. Jose M. Lorenzo is member of the MARCARNE network, funded by CYTED (ref. 116RT0503).Pérez-Santaescolástica, C.; Carballo, J.; Fulladosa, E.; Garcia-Perez, J.; Benedito Fort, JJ.; Lorenzo, J. (2018). Effect of proteolysis index level on instrumental adhesiveness, free amino acids content and volatile compounds profile of dry-cured ham. Food Research International. 107:559-566. https://doi.org/10.1016/j.foodres.2018.03.001S55956610

Optical and X-ray properties of the RIXOS AGN: II - Emission lines

We present the optical and UV emission line properties of 160 X-ray selected AGN taken from the RIXOS survey (including Halpha, Hbeta, [OIII]5007, MgII2798 and CIII]1909). This sample is believed to contain a mixture of absorbed and unabsorbed objects, with column densities up to 4e21 cm-2. Although the distribution of the [OIII] EW for the RIXOS AGN is typical of optically selected samples, the Balmer line EWs are relatively low. This is consistent with the presence of a dust absorber between the broad and narrow line regions (eg. a molecular torus), and intrinsically weak optical line emission. We find Baldwin effects in CIII] and MgII, and a positive response of the MgII line to its ionizing continuum. There is a strong correlation between the EW and FWHM of MgII, which may be similar to that seen in other samples for Hbeta. We demonstrate that this is consistent with models which suggest two line-emitting zones, a `very broad line region' (VBLR) and an `intermediate line region' (ILR). The correlation between EW and FWHM in MgII may be a physical characteristic of the ILR or it may reflect a geometric dependence. We found no correlation between the Hbeta FWHM and the slope of the X-ray spectrum, however this may be due to the effects of dust absorption which suppresses the broad Hbeta component, masking any relationship. The Halpha FWHM does tend to be narrow when alpha_X is soft, and broadens as alpha_X hardens, although the formal probability for this correlation is low (91 per cent). If the distribution of alpha_X in the RIXOS sample reflects the level of intrinsic absorption in these AGN, the data suggest a possible link between the velocity of the Balmer line-emitting region and the amount of absorbing material beyond.Comment: 29 pages, 14 figures, to be published in Monthly Notices of the Royal Astronomical Society. Also available from http://www.mssl.ucl.ac.uk/www_astro/preprints/preprints.htm