Middle pleistocene

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An enigmatic and large-sized specimen of Panochthus (Glyptodontidae, “Panochthini”) from the Ensenadan (Early-Middle Pleistocene) of the Pampean region, Argentina

An enigmatic and large-sized specimen of Panochthus (Glyptodontidae, “Panochthini”) from the Ensenadan (Early-Middle Pleistocene) of the Pampean region, Argentina

Abstract. Panochthus Burmeister (Mammalia, Xenarthra, Glyptodontidae) is one of the best characterized Pleistocene genera. It is possible to recognize 2 Ensenadan (Early-Middle Pleistocene) species from the Pampean region of Argentina and Bolivia, Panochthus intermedius Lydekker and P. subintermedius Castellanos, whereas 2 species are considered as valid for the age Bonaerian-Lujanian (Middle Pleistocene-Late Pleistocene), namely P. tuberculatus Owen and P. frenzelianus Ameghino. This paper provides the first record of a skull belonging to Panochthus from Ensenadan deposits in the Pampean Region of Argentina, being the second record for the genus in this lapse. The synapomorphies that support this taxonomic interpretation are: a frontal-ventrally inclined nasal zone forming a 45º angle between the palate plane and the plane of the upper rostral zone; a cranial length/height ratio that less than 1½ of the height, without considering the descending processes of the zygomatic arch; external nasal openings with a fronto-ventral orientation. A comparative study with P. intermedius and other species from the Bonaerian-Lujanian refutes its placement among any of these; on the other hand, no cranial materials are known for the other species from the Ensenadan (P. subintermedius). Considering that the former is a large species, and that this skull corresponds undoubtedly to a species of Panochthus of large dimensions, the most parsimonious taxonomic hypothesis is to tentatively assign the material MLP 84-IX-2-11 to Panochthus cf. subintermedius. Future findings of more complete materials would provide support or refute this hypothesis.

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Ornamentation and defense structures of the pelvic buckler of Eutatus pascuali (Xenarthra, Dasypodidae)

Ornamentation and defense structures of the pelvic buckler of Eutatus pascuali (Xenarthra, Dasypodidae)

Abstract.- Eutatus pascuali is a large armadillo characteristic of the Lower-Middle Pleistocene of Argentina. The number of published specimens is small and frequently they consist of isolated osteoderms and carapace fragments, in which the dorsal region is usually preserved. In this work we report the presence of modified thick spine-like osteoderms projected laterally on the lateral border of the pelvic buckler. This is a remarkable feature within the Euphractinae that contributes to the knowledge of the appearance of E. pascuali. The presence of spines projecting from the carapace, a convergent adaptation also observed in some Glyptodontinae, could have been developed as a defense against predators.

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Filamentous micro-organisms, inorganic inclusions
				and pseudo-fossils in the Miocene amber from Totolapa (Chiapas,
				Mexico): taphonomy and systematics

Filamentous micro-organisms, inorganic inclusions and pseudo-fossils in the Miocene amber from Totolapa (Chiapas, Mexico): taphonomy and systematics

Although most famous amber-bearing outcrops in Chiapas are those nearby Simojovel, a series of new locations in Chiapas are informally known (Solórzano- Kraemer, 2007; 2010). In these new localities, Totolapa amber is becoming more frequent among specialists interested in the study of amber inclusions (Azar et al., 2010; Durán-Ruiz et al., 2013). Totolapa is found 40 km SE of Chiapa de Corzo (Figure 1) and about 50 km SE of Tuxtla Gutiérrez, in what is geologically known as the Chiapanecan Volcanic Arc (Mora et al., 2007; 2012). Occurrence of amber near Totolapa was formally reported based on the archaeological usage (Bryant, 1983). The author mentions that the amber has a volcanic ash cortex. This observation is very important, since most of the amber pieces are relatively rounded and medium sized (about 3 cm in diameter), have a dark red colour and are included in pyroclastic sediments that also contain carbonized wood and lignitic matter. Occasional reworked marine gastropods and bivalves are also found included in the ash flow, which was deposited during the Pliocene-Pleistocene volcanic event (Damon and Montesinos, 1978). The closest volcanic dome to the Totolapa amber-bearing deposits is that of Venustiano Carranza, with a middle Pleistocene age (0.225 Ma, see Mora et al., 2012). The pyroclastic sediments are underlain by dark gray fine sandstones and mudstones that crop out at the base of the sequence, on sides of the Totolapa River (Figure 2). This unit is lithologically similar to the Simojovel Formation, and includes marine molluscs, corals as well as amber pieces. The marine fauna has not been formally reported but it resembles that of the Miocene amber-bearing units near Simojovel, dated as Early to Middle Miocene (Solórzano-Kraemer, 2007, 2010; Vega et al., 2009a; Perrilliat et al., 2010). Durán-Ruiz et al. (2013) suggest that the amber-bearing Miocene Mazantic Shale and Balumtum Sandstone crop out at Río Salado and Río Yalbantuc, near Totolapa. Thus, amber pieces included in the pyroclastic sequence near Totolapa seem to have been exhumed and reworked during one or several ash flow events that took place during the middle Pleistocene, but the age of the amber remains as Miocene.

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Late Pleistocene mammals from Chivacabé, Huehuetenango, Guatemala

Late Pleistocene mammals from Chivacabé, Huehuetenango, Guatemala

Few Pleistocene paleontological faunas are published in detail for most of Central America. Probably the richest locality of vertebrates in Central America is at Tomayate, El Salvador, and dates to the early-middle Pleistocene. Literature about late Pleistocene vertebrate species from Guatemala is especially scarce. The purpose of the present paper is to introduce the late Pleistocene mammalian remains from Chivacabé, in the western highlands of Guatemala. The Chivacabé fauna radiocarbon dates to between 15,700 and 12,920 calendar years ago. The specimens recovered from excavations between 1977 and1992 are probably only a small portion of the entire fauna likely to exist under 4 to 5 m of redeposited tephra and valley alluvium. Recovered specimens include at least one individual of Glyptotherium sp., three individuals of Cuvieronius cf. C. hyodon, one individual of Equus sp., and two individuals of Odocoileus cf. O. virginianus. One specimen that originally was thought to represent a deer antler is in fact a hyoid bone of Cuvieronius. Previous reports of ‘peccary’ and Eremotherium from Chivacabé are not supported by archived fossils. No faunal specimens exhibit supposed human modification marks purported by previous investigators; all aberrations observed on the bones and teeth can be explained by other taphonomic processes. The Chivacabé fauna represents one of the very few late Pleistocene faunas from Guatemala described thus far. A preliminary list of late Pleistocene localities known in Guatemala suggests that detailed studies of these faunas are warranted.

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The occipital region of late Pleistocene Mylodontidae of Argentina

The occipital region of late Pleistocene Mylodontidae of Argentina

Measurements (Fig. 1). H: maximum height, W: maximum width, EOCCW: external occipital condyles width, IOCCW: internal occipital condyles width, OCCH: occipital condyle height. M1-cond: distance measured from the anterior edge of the first maxillary molariform (M1) to the posterior edge of the occipital condyles. M1-cond is used as an estimator of the length of the cranium to include specimens that do not preserve the premaxilla or the anterior margin of the maxilla (Brambilla & Ibarra 2018). Mean, sample size (n), standard deviation and percent coefficient of variation (CV %) are computed from adults specimens and for species with at least three adult specimens. The specimens of Ensenadan age (Middle Pleistocene) are not included in the measurements, they are considered to refer to ontogenetic patterns and morphological considerations over time in the Scelidotheriinae.

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First report of a South American short-faced bears' den (Arctotherium angustidens): palaeobiological and palaeoecological implications

First report of a South American short-faced bears' den (Arctotherium angustidens): palaeobiological and palaeoecological implications

Geographic and stratigraphic distribution. Early to middle Pleistocene (Ensenadan) of the Pampean region of Argentina, Pleisto- cene of Bolivia (Soibelzon et al. 2005). Diagnosis [following Soibelzon (2004)]. The dorsal border of the foramen magnum is complete (without indentation); there are two ante-orbital foramina; the neurocra- nium is large and laterally compressed; the sagittal crest is well developed; the zygo- matic arches are laterally expanded; the tympanic bulla is flat; the postpalatine margin is V-shaped and does not overpass the distal end of M2. The distal lobes of both I1 and I2 are small; the mesial lobe of I3 is well developed. On P4, the disto- lingual cingulum is absent, and the proto- cone is well developed; the paracone is taller than the metacone. On M1, the crown is wider than long; the parastyle is poorly developed; the lingual border cusps are medium-sized; the hypocone has only one cusp; the protocone is the largest of the lingual cusps. On M2, the parastyle is small in relation to the paracone size, and the talon area is well developed and differen- tiated.

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Mathematics examination anxiety of middle school seniors

Mathematics examination anxiety of middle school seniors

The problem of this research is determining the level of MEA of middle school seniors’. Mathematics test anxiety originates from fear and negative emotional reactions. Anxiety is associated with panic, nervousness, restlessness, helplessness, trembling and confusion that arise in students when mathematics or mathematics tests are mentioned (Ugodulunwa & Okolo, 2015). In this research, MEA means the scores that students got at “Mathematics Examination Anxiety Scale” (Şan, 2014). The sub-dimensions of the scale help to measure both facilitating and debilitating anxiety about the mathematics test. The higher scale score means the more debilitating MEA.

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How does monetary policy affect the income class structure? Evidence from the Eurozone.

How does monetary policy affect the income class structure? Evidence from the Eurozone.

This paper evaluates how monetary policy affects the income class structure by stimulating economic activity and employment for the panel of countries that originated the Economic and Monetary Union that originated the Union (EMU-11). We examine the effect of monetary policy on the different classes of the income distribution. Our interest on the lower income class lies in the substantial dependence of these households on labour income and their likelihood to react significantly to monetary policy impulses that stimulate the economic activity. In comparative terms, we are interested also on studying the effect of monetary policy on the upper part of income distribution, which relies relatively more on business and capital income. In particular, we distinguish between lower, lower-middle, upper-middle and upper classes. We apply a Bayesian vector autoregressive (BVAR) model to assess possible impacts of monetary policy on the size of the respective income classes over the period 2007Q3-2016Q1. Our findings suggest a non-homogeneous effect of monetary policy on the income classes, although the impact of other intermediate variables does seem to have had a rather uniform effect on the distribution of income.

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Polarization and the middle class in Uruguay

Polarization and the middle class in Uruguay

lifestyles and economic and social attitudes (Lora and Fajardo, 2011). Goldthorpe (1980) develops a social stratification analysis with seven categories in terms of source and level of personal income, degree of economic security and possibility of economic advancement, location within the systems of authority and control of production processes and performing their tasks and roles (Marshall, 1998 and Goldthorpe, 1980). The middle class in economics is usually defined on the basis of the distribution of a social welfare indicator such as household income (the most commonly used), household expenditure, labor status, educational attainment, etc. Most of the time economists use objective income definitions but some authors use self-perceived social status measures (Lora and Fajardo, 2011). In a new approach, López- Calva and Ortiz Suarez (2012) develop a vulnerability approach using the probability of falling into poverty, in order to determine the lower income bound of the middle class. In this paper, the definition of the middle class is related to the distribution of one variable: income. Therefore, the main problem is the arbitrary identification of the range of the income distribution that represents the middle class. The literature is not unanimous on this issue (see Foster and Wolfson, 2009 for further discussion of developed countries and Cruces et al., 2010 for developing countries) and dif ferent definitions could lead to diverse and incomparable results. In order to analyze the evolution of the middle class, Foster and Wolfson (2009) develop a methodology that lacks arbitrariness in that it is based on the concept of “partial orderings” and first (and second) degree stochastic dominance. This method yields two curves (one for each population we would like to compare) that enables us to unambiguously determine which distribution concentrates more population around its median and also a bipolarization index. Another complementary measure that enables comparison of the entire income distribution at two dif ferent points in time, in order to analyze the evolution of the entire distribution, is that developed by Handcock and Morris (1998, 1999). They provide the theoretical framework for the relative distribution approach, which enables us to compare two dif ferent distributions. Moreover, this non-parametric methodology gives us the tools to separately estimate the ef fects attributable to changes in the shape of the income distribution and those which come from changes in the location of the income distribution.

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Development of reinforced and cell laden vascular grafts structurally inspired by human coronary artery

Development of reinforced and cell laden vascular grafts structurally inspired by human coronary artery

Cardiovascular diseases are the world leading cause of death, with coronary artery disease as the predominant one. Although autologous vessels remain as the best coronary revascularization alternative, its application is limited by pre-existing vascular problems, previous operations, and low quality of vessels, among others. One challenge is to develop vascular grafts capable of showing good biological and mechanical performance and long patency once implanted. For this, it is necessary to deeply understand artery structure, components, and biological and mechanical properties. None of the currently existing vascular grafts has been able to fulfill all the requirements, especially compliance and non-thrombogenicity. Inspired by the human coronary artery structure, a new manufacturing method was developed to fabricate vascular grafts with these requirements. A combination of dipping-spinning and solution blow spinning techniques, controlled by a robot device was used to manufacture cellularized multilayer tubular structures. To mechanically reinforce the vascular grafts polycaprolactone fibers were distributed resembling collagen fibers in coronary arteries. Gelatin-alginate hydrogel layers with cell encapsulated were intercalated with fiber layers to enhance the biological function. Furthermore, middle and outer layer compositions, wavy and oriented distribution of fibers were separately optimized mimicking media and adventitia layers respectively to achieve similar mechanical properties. Composition was successfully optimized to have a stress-strain curve close to the media and adventitia curves. Vascular grafts fabricated in this work showed mechanical behavior within the coronary arteries’s ranges and statistically similar compliance to coronary arteries at physiological pressure. Finally, cells were incorporated and distributed homogeneously throughout the vascular graft, showing proliferation at in vitro culture. These results demonstrate that vascular grafts with similar biological and mechanical properties to coronary arteries can be produced by automatable manufacturing method inspired in the artery structure.

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The New Shift in the Cooperation of the European Union With Middle and Upper-Middle-Income Countries

The New Shift in the Cooperation of the European Union With Middle and Upper-Middle-Income Countries

The new European Consensus on Development tries to adapt the development policy of the EU to the new emerging world order, in which the EU considers these middle and upper-middle-income countries as key actors for the achievement of the objectives of the 2030 Agenda and strategic partners in the EU’s objective of reducing and, ultimately, eradicating, poverty. From now on, the negotiated normative guidance could be combined with operational flexibility by adapting the action to the specific objectives of the EU and to the requirements of the partner countries. The collaboration with different actors both inside and outside the EU, the private sector, local authorities, and civil society would also bring specific advantages. However, it is necessary to continue using the toolbox that the EU already has to apply them to each country in order to set out to make development aid effective.

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Extinct and extant sand dollars (Clypeasteroida: Echinoidea) from Uruguay

Extinct and extant sand dollars (Clypeasteroida: Echinoidea) from Uruguay

and del Río 2002a). Moreover, Scarabino (1977) stressed the faunistic complexity of the area, emphasizing the role of the Rio de la Plata as a barrier for some supra- to infralittoral com- munities. As seen in Fig. 1, only Encope emar- ginata passes through this barrier. Although this would favor the salinity factor as pre- dominant, studies on mollusks show that dur- ing the Pleistocene-Holocene transgressions, temperatures higher than present were recorded (Martínez 1990, Martínez et al. 2001).

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Enfoque Middle-Out en la Construcción e Integración de  Escenarios

Enfoque Middle-Out en la Construcción e Integración de Escenarios

varios autores (Potts 1995), (Booch 1991), (Jacobson et al. 1992), (Zorman 1995) y dichas propuestas son muy importantes para extender el uso de escenarios en la práctica real. Sin embargo, un análisis detallado de las recomendaciones y conclusiones muestra algún grado de dispersión y contradicciones. Esta falta de precisión sobre cuándo y cómo los escenarios deberían usarse ha sido extendida a quienes usan estas técnicas en la práctica. Por eso la mayoría de los desarrolladores ven la creación de escenarios como un arte más que como una tarea de ingeniería. Estudios recientes relativos al uso real de escenarios en la Ingeniería de Requisitos (Weidenhaupt et al. 1998) (Rolland et al. 1998) han probado claramente este hecho y señalado la necesidad de más definiciones detalladas acerca de la construcción de escenarios como una contribución ineludible para incrementar su uso en situaciones reales. Esto está en completo acuerdo con Sutcliffe (1997a), quien piensa que hay poca comprensión acerca de cómo los escenarios deberían construirse, poca evidencia acerca de su efectividad y menos aún de por qué funcionan. La variedad de interpretaciones, sintaxis y mecanismos de construcción de escenarios va más allá hasta mostrar contradicciones básicas, dado que no existe acuerdo entre los autores acerca de qué enfoque debe recomendarse para el proceso de construcción de escenarios: top-down o bottom-up. Este artículo se basa en la hipótesis que la diversidad de los criterios proviene precisamente de esta alternativa, y creemos que es una falsa opción en el sentido que no debe seguirse ni un enfoque top-down ni un enfoque bottom-up, sino uno “middle-out”.

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Financial development and the distribution of income in Latina America and the Caribbean

Financial development and the distribution of income in Latina America and the Caribbean

Next, we examine the regression for the richest quintile Q5. While the growth of GDP per capita raised the income of the rich, the evidence does not support a disproportionate effect of financial development as the estimated coefficient is not statistically significant. Finally, the last column of Table 3 reports the regression with the Gini coefficient as the dependent variable. The estimated coefficient for Private Credit is negative which would indicate that financial development may have reduced inequality in LAC. However, since the estimated coefficient is not statistically significant it is more correct to say that it has not affected the Gini coefficient. Recall that the Gini coefficient summarizes the whole income distribution in one number which is not an easy task. Given that financial development appears to not have affected the poorest and the richest quintiles, but affected the low-middle, middle, and middle-high income groups to different degrees, it is possible that Private Credit has had no effect on the Gini measure of inequality.

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AZOKH CAVE LITHIC ASSEMBLAGES AND THEIR CONTEXTUALIZATION IN THE MIDDLE AND UPPER PLEISTOCENE OF SOUTHWEST ASIA

AZOKH CAVE LITHIC ASSEMBLAGES AND THEIR CONTEXTUALIZATION IN THE MIDDLE AND UPPER PLEISTOCENE OF SOUTHWEST ASIA

Derricourt 2006, Bar-Yosef & Belmaker 2011). During the Miocene there was a land bridge between Africa and the Levant, allowing the migration of various plants and animals through this territory (Tchernov 1988, Bar-Yosef 1994, 1998a). Moreover the region was accessible via southern (Bab-el-Mandeb straight) and northern (Nile river and Sinai Peninsula) paths, which during the Early and Middle Pleistocene served as potential dispersal routes for hominin migrations. This is attested by several as yet undated sites in the Levant (e.g. Yiron with evidence of a core and flake industry (Ronen 1991a), the Erq el Ahmar Formation in the Jordan Valley, which is considered to be „prior to the Ubeidiya‟ formation identified with the Olduvai subchron (Ron & Levi 2001, Bar-Yosef & Belmaker 2011) and in the Caucasus (e.g. Kvabedi with a number of assemblages derived from various accumulations (Vekua & Lordkipanidze 2008, Agustí et al. 2009). Based on correlation of the faunal assemblage and the stratigraphic sequence with other sites within the region and also the sites of similar chronology in Europe, an age older than 1.8 Ma is suggested for these sites. Several well excavated and contextualised sites with evidence of early hominin anthropological and cultural remains in this region are known too which cover an age span between 1.8 – 0.8 Ma. Of great importance are the sites of „Ubeidiya, Evron-Quary, Latamne, Bizat Ruhama, and Gesher Benot Ya‟aqov in the Levant (Ronen 1991b, Bar-Yosef & Goren- Inbar 1993, Sanlaville et al. 1993, Ronen et al. 1998, Bar Yosef & Belfer-Cohen 2001, Ron and Gvirtzman 2001, Ron et al. 2003, Zaidner et al. 2003, 2010), Dmanisi in the Caucasus (Gabunia & Vekua 1995, Rightmire et al. 2006, Lordkipanidze et al. 2007), and Dursunlu and Keltepe Deresi (layers V – XII) in Central Anatolia (Güleç et al. 1999, 2009, Slimak et al. 2004, 2008, Kuhn 2010). Hominin presence and their dispersal through Southwest Asian regions is confirmed also by a number of other Middle and Upper Pleistocene sites (see below).

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Middle East and democracy, february 2013

Middle East and democracy, february 2013

This war took place following the Egyptian decision to seal the Straits of Tiran (1955) and to nationalise the Suez Canal (26 July 1956). This provided the casus belli for Israel, France and the UK. Paris and London considered that their vital interests had been damaged with the nationalisation of Suez and decided to help Israel in its pre-emptive incursion in the Sinai on 29 October. This war consisted of two separate military operations: one Anglo-French and one Israeli. The USSR and the USA agreed on the need to avoid a new colo- nial war and, on 2 November 1956, the UN general Assembly approved a US- sponsored resolution for an intermediate ceasefire and the withdrawal of all forces from Egyptian territory. As a result, France and the UK appeared as the losers of this war while both Israel and Egypt had gained something. Israel’s military reputation had been further enhanced elevating its status to that of a regional super-power. Despite the military defeat for Egypt, Nasser emerged on the winning side as an ascendant political leader, whose influence went beyond Egypt and reached the entire Arab world. Finally, the US and the Sovi- et Union increased their presence in the Middle East, at the expense of the European powers.

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The Middle East After September 11

The Middle East After September 11

For over five decades, the Middle East was synonymous with the Arab Israeli conflict. Since the UN resolution 181 of 1947 divided Palestine under the British mandate into two states: one Jewish and one Arab, each on 50% of the land, this region and the world has known five decades of intense conflict with more than five major wars, two colossal uprisings and countless victims. From the outset, a grave feeling of injustice befell the Arab population in Palestine and the rest of the Arab World. They felt that the land allocated by the UN to the Jewish population of Palestine – which roughly constitued 22% of the total then – was far greater land than it really might have been entitled to. The fact that Israel ended up gaining 28% more land after the first war with the Arabs in 1948 intensified those feelings. The plight of the Palestinian refugees driven away from their homeland during the hostilities compounded those feelings much further. Sentiments of historic injustice remain to this day and are critical in

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NO TIME TO WASTE, APPLYING THE LESSONS FROM LATIN AMERICA´S 50 YEARS F HOUSING POLICY TO RAPIDLY URBANIZING COUNTRIES, 2018

NO TIME TO WASTE, APPLYING THE LESSONS FROM LATIN AMERICA´S 50 YEARS F HOUSING POLICY TO RAPIDLY URBANIZING COUNTRIES, 2018

finance the new houses they used resources from a variety of sources: the national budget; allocations from specific sources (for instance a per cent of the gas tax yield in Argentina); or worker´s savings in the social security system. Housing ministries, housing banks, or public housing corporations produced limited quantities of new houses or subsidized mortgages but never attained the scale and sustainability to fully address the housing problem created by rapid urbanization. These public housing entities faced endemic shortages of resources due to competing demands on the public budget and high arrears in their loan portfolios. In the mid-1970s many countries produced serviced lots to accommodate the growing demand for housing by low-income households but beneficiaries of these programs never got support to expand and improve their shelters, preventing these programs from achieving the intended results (Rojas 1995). In most cases public housing entities were inefficient producers of houses or serviced lots and often miss-targeted the allocation of their products due to political pressures that funnelled the new houses to middle-income households affiliated with strong trade unions or working in the civil service. In the majority of cases, low-income households were left to solve their housing problem in the informal sector. The Latin American experience proves that the provision of finished houses and financing by public entities does not satisfy the needs of the growing urban population. There are no reasons to think that SA and SSA countries that are building new houses directly would do better as the volume of new houses thy manage to build is very small in relation to needs a situation that leads the majority of households (over 80 per cent in some cases) to self-build their shelter informally (World Bank 2016, UN Habitat 2014).

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Man in the middle attacks on SSL/TLS

Man in the middle attacks on SSL/TLS

El ataque que se utilizará será el Man-in-the-middle que consiste en que el atacante se interpone entre el cliente y el servidor. Con este ataque demostraremos como se pueden obtener credenciales en una conexión segura. En primer lugar el atacante se introducirá en la red del atacado a partir de un ataque vía WIFI, para acceder a la red local. Una vez introducidos en la red se realizará un envenenamiento del router, para que nos redireccione los paquetes del cliente, y finalmente utilizaremos una herramienta para ver el texto en plano. Ver figura 1.1.

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