Slow Tourism: A Possible Solution to Indigenous Communities’ Invisibility in San Cristobal de las Casas

Tourism is Mexico’s second largest service industry and makes up a significant amount of the country’s revenue. Scholars have considered and described the impact of Indigenous exploitation on the tourism industry; however, researchers have generally limited their investigation to the social conflict between Indigenous communities, mestizos, and tourists, instead of providing sustainable solutions to an issue that has worsened with time. Parallelly, even though recent studies have suggested Slow Tourism as a development tool to the economy, their proposal does not consider Indigenous communities as active agents. We report the results of descriptive research design, considered from a transactionalist framework, from which we draw potential steps towards a sustainable and fair industry; this methodology allows accurate description of the Fast Tourism phenomenon. Through field work in non-participant observation and field notes gathered in the span of four weeks, the observation process develops in a three-stage funnel system, manifested in the appendix. This study aims to shift the current international and capitalist touristic models to fit Indigenous communities’ necessities and values through the implementation of Slow Tourism practices

Cell-mediated immune status in patients with squamous cell carcinoma of the oral cavity

Sixteen untreated patients with squamous cell carcinoma of the oral cavity were tested for in vitro immune status in comparison with the normal healthy donors. The parameters investigated were total leukocyte and lymphocyte counts, percentages and absolute counts of T- and B-cells in circulation, subsets of T-cells identified by the Fc receptors, phytohemagglutinin (PHA), and mixed lymphocyte culture (MLC) responses, natural killer (NK) and antibody-dependent cellular cytotoxicity (ADCC) activities, and circulating immune complexes (CICs). Eight of these patients were retested 3 to 6 months after surgery. The results showed that there was an increase in leukocyte and lymphocyte counts, an increase in the percentage and absolute number of B-lymphocytes, an increase in the percentage of T-gamma cells, suboptimal PHA and MLC responses, normal NK and ADCC activities, and increased levels of CICs in untreated oral cancer patients. In the postoperative stage, except for a reduction in leukocyte and lymphocyte counts, other abnormalities remained unchanged. The CICs in treated patients correlated with the tumor load in that in three patients showing recurrence, the CIC level remained elevated, whereas in patients without evidence of the disease the CIC level was either low or comparable to the upper normal limits

Performance optimisation of the MAC protocol with multiple contention slots in MIMO ad hoc networks

The multiple-input multiple-output (MIMO) technique can be used to improve the performance of ad hoc networks. Various medium access control (MAC) protocols with multiple contention slots have been proposed to exploit spatial multiplexing for increasing the transport throughput of MIMO ad hoc networks. However, the existence of multiple request-to-send/clear-to-send (RTS/CTS) contention slots represents a severe overhead that limits the improvement on transport throughput achieved by spatial multiplexing. In addition, when the number of contention slots is fixed, the efficiency of RTS/CTS contention is affected by the transmitting power of network nodes. In this study, a joint optimisation scheme on both transmitting power and contention slots number for maximising the transport throughput is presented. This includes the establishment of an analytical model of a simplified MAC protocol with multiple contention slots, the derivation of transport throughput as a function of both transmitting power and the number of contention slots, and the optimisation process based on the transport throughput formula derived. The analytical results obtained, verified by simulation, show that much higher transport throughput can be achieved using the joint optimisation scheme proposed, compared with the non-optimised cases and the results previously reported

Modelling the impact of interventions on imported, introduced and indigenous malaria infections in Zanzibar, Tanzania

Malaria cases can be classified as imported, introduced or indigenous cases. The World Health Organization's definition of malaria elimination requires an area to demonstrate that no new indigenous cases have occurred in the last three years. Here, we present a stochastic metapopulation model of malaria transmission that distinguishes between imported, introduced and indigenous cases, and can be used to test the impact of new interventions in a setting with low transmission and ongoing case importation. We use human movement and malaria prevalence data from Zanzibar, Tanzania, to parameterise the model. We test increasing the coverage of interventions such as reactive case detection; implementing new interventions including reactive drug administration and treatment of infected travellers; and consider the potential impact of a reduction in transmission on Zanzibar and mainland Tanzania. We find that the majority of new cases on both major islands of Zanzibar are indigenous cases, despite high case importation rates. Combinations of interventions that increase the number of infections treated through reactive case detection or reactive drug administration can lead to substantial decreases in malaria incidence, but for elimination within the next 40 years, transmission reduction in both Zanzibar and mainland Tanzania is necessary

The impact of reactive case detection on malaria transmission in Zanzibar in the presence of human mobility

Malaria persists at low levels on Zanzibar despite the use of vector control and case management. We use a metapopulation model to investigate the role of human mobility in malaria persistence on Zanzibar, and the impact of reactive case detection. The model was parameterized using survey data on malaria prevalence, reactive case detection, and travel history. We find that in the absence of imported cases from mainland Tanzania, malaria would likely cease to persist on Zanzibar. We also investigate potential intervention scenarios that may lead to elimination, especially through changes to reactive case detection. While we find that some additional cases are removed by reactive case detection, a large proportion of cases are missed due to many infections having a low parasite density that go undetected by rapid diagnostic tests, a low rate of those infected with malaria seeking treatment, and a low rate of follow up at the household level of malaria cases detected at health facilities. While improvements in reactive case detection would lead to a reduction in malaria prevalence, none of the intervention scenarios tested here were sufficient to reach elimination. Imported cases need to be treated to have a substantial impact on prevalence