Political participation rates have declined steadily in Mexico since the 1990s. The decline has been most severe among the poor, producing a stratified pattern that more and more mirrors Mexico's ...severe socioeconomic inequalities. Poverty of Democracy examines the political marginalization of Mexico's poor despite their key role in the struggle for democracy.Claudio A. Holzner uses case study evidence drawn from eight years of fieldwork in Oaxaca, and from national surveys to show how the institutionalization of a free-market democracy created a political system that discourages the political participation of Mexico's poor by limiting their access to politicians at the local and national level. Though clean elections bolster political activity, Holzner shows that at the local level, and particularly in Mexico's poorest regions, deeply rooted enclaves of authoritarianism and clientelism still constrict people's political opportunities.
To explain this phenomenon, Holzner develops an institutional theory in which party systems, state-society linkages, and public policies are the key determinants of citizen political activity. These institutions shape patterns of political participation by conferring and distributing resources, motivating or discouraging an interest in politics, and by affecting the incentives citizens from different income groups have for targeting the state with political activity.
Holzner's study sheds light on a disturbing trend in Latin America (and globally), in which neoliberal systems exacerbate political and economic disparities and create institutions that translate economic inequalities into political ones.
This paper aims at elucidating which factors are effective in terms of influencing the die swell of unvulcanized rubber upon extrusion. To that end, compression, viscosity, and extrusion tests were ...performed on two types of ethylene–propylene–diene rubbers, while additional compression tests were performed on natural rubber. First, all three testing modalities were assessed separately, revealing that for the tested materials the compressibility is pressure-dependent; the viscosity is velocity-dependent; and the die swell is influenced by several, partly intertwined factors. In order to better understand the collected experimental data, we have employed the theoretical tool of dimensional analysis, showing that the compressibility of unvulcanized rubber is of great importance for the die swell. Surprisingly, the temperature dependence of the die swell turns out to be much less prominent than standardly assumed. Further key factors influencing the die swell concern the geometries of the die and of the canal.
•New extrusion test modalities are presented.•Dimensional analysis is proposed as theoretical concept for analysis of extrusion tests.•Temperature turns out as less influential for rubber compressibility and viscosity than expected.•The importance of the rubber compressibility for its extrusion behavior is corroborated.
Despite considerable ongoing efforts, accurate computational simulation of the flow behavior of (unvulcanized) rubber remains an open challenge. There is growing evidence that one of the reasons for ...that is insufficient consideration of, or knowledge on, the mechanical compressibility of the material. As a contribution to tackle this open question, we here report on a series of hydrostatic compression tests performed on natural rubber, as well as on two types of EPDM (ethylene-propylene-diene-monomer) rubber compounds. These materials were filled into a capillary rheometer with closed extrusion canal, and then compressed and released through volume changes realized at different speeds, while monitoring the corresponding hydrostatic pressures acting on the investigated rubbers. The volume changes then entered various relevant strain measures (Green-Lagrange strains, Hencky strains, linearized strains), while the pressures were mathematically transformed into energetically conjugate stress measures (second Piola-Kirchhoff stress, Kirchhoff stress, Cauchy stress). Insertion of these measures into the dissipation inequality resulting from the two fundamental laws of thermodynamics, revealed that the investigated materials behave purely elastically under hydrostatic pressure, albeit in a non-linear fashion. Irrespective of the format chosen for elasticity theory, the elastic bulk modulus appears as a power function of the hydrostatic pressure; the former increasing under-linearly, but non-asymptotically, with the latter. Careful statistical evaluation of the corresponding power law coefficients allows for derivation of upper and lower bounds of the bulk modulus, as functions of the hydrostatic pressure, an information which may prove essential for improving the accuracy of rubber extrusion simulations.
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•A new experimental setup for testing the compressibility of rubber is introduced.•Natural and EPDM rubber turn out to be remarkably compressible.•Under hydrostatic compression, rubber behaves non-linearly elastically.•The elastic bulk modulus increases with the applied pressure, according to a power function.•2D-confidence ellipses for power law parameters are presented.
Background It has been shown that crystalloid fluid-overload promotes anastomotic instability. As physiologic anastomotic healing requires the sequential infiltration of different cells, we ...hypothesized this to be altered by liberal fluid regimes and performed a histomorphological analysis. Methods 36 Wistar rats were randomized into 4 groups (n=8-10 rats/group) and treated with either liberal (+) or restrictive (−) perioperative crystalline (Jonosteril® = Cry) or colloidal fluid (Voluven® = Col). Anastomotic samples were obtained on postoperative day 4, routinely stained and histophathologically reviewed. Anastomotic healing was assessed using a semiquantitative score, assessing inflammatory cells, anastomotic repair and collagenase activity. Results Overall, the crystalloid overload group (Cry (+)) showed the worst healing score ( P < 0.01). A substantial increase of lymphocytes and macrophages was found in this group compared to the other three ( P < 0.01). Both groups that received colloidal fluid (Col (+) and Col (−)) as well as the group that received restricted crystalloid fluid resuscitation (Cry (−)) had better intestinal healing. Collagenase activity was significantly higher in the Cry (+) group. Conclusion Intraoperative infusion of high-volume crystalloid fluid leads to a pathological anastomotic inflammatory response with a marked infiltration of leukocytes and macrophages resulting in accelerated collagenolysis.
Twenty years after governments across Latin America began implementing neoliberal reforms in earnest, concern is growing about their impact on the quality of democracy in the region. This article ...examines this issue in the case of Mexico by exploring how patterns of political participation, especially among the rural and urban poor, have changed since the implementation of free market reforms. It asks whether the institutional innovations associated with free market reforms make it easier or more difficult for the poor to participate in Mexico's political process. The answer is not encouraging. Despite democratic openings, the new linkages between the state and citizens established as a result of the transition to a free market development model stifle the voice of the poor not through the threat of force or coercion, but by creating obstacles and disincentives for political mobilization that affect the poor more severely than other groups.
Metastasized colorectal cancer (CRC) is associated with a poor prognosis and rapid disease progression. Besides hepatic metastasis, peritoneal carcinomatosis is the major cause of death in Union for ...International Cancer Control (UICC) stage IV CRC patients. Insights into differential site-specific reconstitution of tumor cells and the corresponding tumor microenvironment are still missing. Here, we analyzed the transcriptome of single cells derived from murine multivisceral CRC and delineated the intermetastatic cellular heterogeneity regarding tumor epithelium, stroma, and immune cells. Interestingly, we found an intercellular site-specific network of cancer-associated fibroblasts and tumor epithelium during peritoneal metastasis as well as an autologous feed-forward loop in cancer stem cells. We furthermore deciphered a metastatic dysfunctional adaptive immunity by a loss of B cell-dependent antigen presentation and consecutive effector T cell exhaustion. Furthermore, we demonstrated major similarities of this murine metastatic CRC model with human disease and - based on the results of our analysis - provided an auspicious site-specific immunomodulatory treatment approach for stage IV CRC by intraperitoneal checkpoint inhibition.
The management of metastatic hepatocellular carcinoma (HCC) is complex, particularly when complicated by pulmonary embolism. In these cases, atezolizumab-bevacizumab therapy is contraindicated due to ...an elevated risk of thromboembolic events. Differentiating pulmonary tumor embolism from thromboembolic disease is diagnostically challenging. This report outlines the benefit of transcatheter aspiration to obtain pathological evidence of pulmonary artery tumor embolus in an HCC patient. The intervention enabled a significant shift in the management strategy, leading to an escalation of systemic HCC therapy. This case underscores the importance of precise diagnostic techniques such as transcatheter aspiration in guiding treatment decisions, particularly in cases where pulmonary embolism may signify an underlying malignancy-driven process.
In unresectable patients with metastatic colorectal cancer (CRC), the site of the primary is a strong prognostic factor warranting major adjustments in palliative medical treatment. Initial results ...suggested that the site of CRC influences prognosis after curative resection of colorectal liver metastases (CLM). In this study, we evaluated outcome after resection of isolated CLM with regard to the location of the primary.
221 patients with macroscopically complete resection of CLM and no known extrahepatic disease were identified. 63 patients had right-sided and 158 had left-sided CRC. Tumors of the transverse colon and rectum were excluded. Survival was evaluated using the Kaplan–Meier method.
Characteristics of CLM, primary tumor stage and chemotherapeutic regimens were not significantly different between the two groups. Kaplan–Meier five-year survival was comparable (41%) in patients with right- or left-sided CRC (p = 0.64). Microscopic resection margin, number of liver metastases, age and nodal status but not the site of the primary tumor significantly influenced survival.
The site of the colorectal primary in this well-defined group of patients after resection of isolated CLM did not prove to be of significant prognostic value. Whether the primary tumor in CLM is located on the left side or the right should not preclude patients from surgery.
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