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Resurgence of Malaria in Quetta  [PDF]
Arsala Mansoor,Shah Mohd. Marri,Hasnain Naqvi
Journal of Medical Sciences , 2003,
Abstract: The prevalence of malaria in Quetta was estimated from blood films made during malaria survey, held over 12 consecutive months. The highest parasite rate occurred during the months of August-October. Plasmodium vivax was the most common infecting species of mosquitoes during the year, while Plasmodium falciparum predominated the later transmission season. The data also reveal the slight prevalence of malaria in the male members of the family, and in the children between 1-16 years. The data pertaining to the years 1995-1998 reveal the resurgence of malaria intensity.
Prevention of Malaria Resurgence in Greece through the Association of Mass Drug Administration (MDA) to Immigrants from Malaria-Endemic Regions and Standard Control Measures  [PDF]
Maria Tseroni?,Agoritsa Baka?,Christina Kapizioni?,Georges Snounou?,Sotirios Tsiodras?,Maria Charvalakou?,Maria Georgitsou?,Maria Panoutsakou?,Ioanna Psinaki?,Maria Tsoromokou
PLOS Neglected Tropical Diseases , 2015, DOI: 10.1371/journal.pntd.0004215
Abstract: Greece was declared malaria-free in 1974 after a long antimalarial fight. In 2011–2012, an outbreak of P. vivax malaria was reported in Evrotas, an agricultural area in Southern Greece, where a large number of immigrants from endemic countries live and work. A total of 46 locally acquired and 38 imported malaria cases were detected. Despite a significant decrease of the number of malaria cases in 2012, a mass drug administration (MDA) program was considered as an additional measure to prevent reestablishment of the disease in the area. During 2013 and 2014, a combination of 3-day chloroquine and 14-day primaquine treatment was administered under direct observation to immigrants living in the epicenter of the 2011 outbreak in Evrotas. Adverse events were managed and recorded on a daily basis. The control measures implemented since 2011 continued during the period of 2013–2014 as a part of a national integrated malaria control program that included active case detection (ACD), vector control measures and community education. The MDA program was started prior to the transmission periods (from May to December). One thousand ninety four (1094) immigrants successfully completed the treatment, corresponding to 87.3% coverage of the target population. A total of 688 adverse events were recorded in 397 (36.2%, 95% C.I.: 33.4–39.1) persons, the vast majority minor, predominantly dizziness and headache for chloroquine (284 events) and abdominal pain (85 events) for primaquine. A single case of primaquine-induced hemolysis was recorded in a person whose initial G6PD test proved incorrect. No malaria cases were recorded in Evrotas, Laconia, in 2013 and 2014, though three locally acquired malaria cases were recorded in other regions of Greece in 2013. Preventive antimalarial MDA to a high-risk population in a low transmission setting appears to have synergized with the usual antimalarial activities to achieve malaria elimination. This study suggests that judicious use of MDA can be a useful addition to the antimalarial armamentarium in areas threatened with the reintroduction of the disease.
Malaria resurgence: a systematic review and assessment of its causes
Justin M Cohen, David L Smith, Chris Cotter, Abigail Ward, Gavin Yamey, Oliver J Sabot, Bruno Moonen
Malaria Journal , 2012, DOI: 10.1186/1475-2875-11-122
Abstract: A systematic review of the literature was conducted to identify historical malaria resurgence events. All suggested causes of these events were categorized according to whether they were related to weakened malaria control programmes, increased potential for malaria transmission, or technical obstacles like resistance.The review identified 75 resurgence events in 61 countries, occurring from the 1930s through the 2000s. Almost all resurgence events (68/75?=?91%) were attributed at least in part to the weakening of malaria control programmes for a variety of reasons, of which resource constraints were the most common (39/68?=?57%). Over half of the events (44/75?=?59%) were attributed in part to increases in the intrinsic potential for malaria transmission, while only 24/75 (32%) were attributed to vector or drug resistance.Given that most malaria resurgences have been linked to weakening of control programmes, there is an urgent need to develop practical solutions to the financial and operational threats to effectively sustaining today’s successful malaria control programmes.
Long-Term Responses of the Endemic Reef-Builder Cladocora caespitosa to Mediterranean Warming  [PDF]
Diego K. Kersting, Nathaniel Bensoussan, Cristina Linares
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0070820
Abstract: Recurrent climate-induced mass-mortalities have been recorded in the Mediterranean Sea over the past 15 years. Cladocora caespitosa, the sole zooxanthellate scleractinian reef-builder in the Mediterranean, is among the organisms affected by these episodes. Extensive bioconstructions of this endemic coral are very rare at the present time and are threatened by several stressors. In this study, we assessed the long-term response of this temperate coral to warming sea-water in the Columbretes Islands (NW Mediterranean) and described, for the first time, the relationship between recurrent mortality events and local sea surface temperature (SST) regimes in the Mediterranean Sea. A water temperature series spanning more than 20 years showed a summer warming trend of 0.06°C per year and an increased frequency of positive thermal anomalies. Mortality resulted from tissue necrosis without massive zooxanthellae loss and during the 11-year study, necrosis was recorded during nine summers separated into two mortality periods (2003–2006 and 2008–2012). The highest necrosis rates were registered during the first mortality period, after the exceptionally hot summer of 2003. Although necrosis and temperature were significantly associated, the variability in necrosis rates during summers with similar thermal anomalies pointed to other acting factors. In this sense, our results showed that these differences were more closely related to the interannual temperature context and delayed thermal stress after extreme summers, rather than to acclimatisation and adaption processes.
Reproductive Efficiency of a Mediterranean Endemic Zooxanthellate Coral Decreases with Increasing Temperature along a Wide Latitudinal Gradient  [PDF]
Valentina Airi, Francesca Gizzi, Giuseppe Falini, Oren Levy, Zvy Dubinsky, Stefano Goffredo
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0091792
Abstract: Investments at the organismal level towards reproduction and growth are often used as indicators of health. Understanding how such energy allocation varies with environmental conditions may, therefore, aid in predicting possible responses to global climatic change in the near future. For example, variations in seawater temperature may alter the physiological functioning, behavior, reproductive output and demographic traits (e.g., productivity) of marine organisms, leading to shifts in the structure, spatial range, and abundance of populations. This study investigated variations in reproductive output associated with local seawater temperature along a wide latitudinal gradient on the western Italian coast, in the zooxanthellate Mediterranean coral, Balanophyllia europaea. Reproductive potential varied significantly among sites, where B. europaea individuals from the warmest site experienced loss of oocytes during gametogenesis. Most of the early oocytes from warmest sites did not reach maturity, possibly due to inhibition of metabolic processes at high temperatures, causing B. europaea to reabsorb the oocytes and utilize them as energy for other vital functions. In a progressively warming Mediterranean, the efficiency of the energy invested in reproduction could be considerably reduced in this species, thereby affecting vital processes. Given the projected increase in seawater temperature as a consequence of global climate change, the present study adds evidence to the threats posed by high temperatures to the survival of B. europaea in the next decades.
Resurgence and Topological Strings  [PDF]
Marcel Vonk
Mathematics , 2015,
Abstract: The mathematical idea of resurgence allows one to obtain nonperturbative information from the large-order behavior of perturbative expansions. This idea can be very fruitful in physics applications, in particular if one does not have access to such nonperturbative information from first principles. An important example is topological string theory, which is a priori only defined as an asymptotic perturbative expansion in the coupling constant g_s. We show how the idea of resurgence can be combined with the holomorphic anomaly equation to extend the perturbative definition of the topological string and obtain, in a model-independent way, a large amount of information about its nonperturbative structure.
Resurgence in extended hydrodynamics  [PDF]
Inês Aniceto,Micha? Spaliński
Physics , 2015,
Abstract: It has recently been understood that the hydrodynamic series generated by the M\"uller-Israel-Stewart theory is divergent, and that this large order behaviour is consistent with the theory of resurgence. Furthermore, it was observed, that the physical origin of this is the presence of a purely damped nonhydrodynamic mode. It is very interesting to ask whether this picture persists in cases where the spectrum of nonhydrodynamic modes is richer. We take the first step in this direction by considering the simplest hydrodynamic theory which, instead of the purely damped mode, contains a pair of nonhydrodynamic modes of complex conjugate frequencies. This mimics the pattern of black brane quasinormal modes which appear on the gravity side of the AdS/CFT description of \symm\ plasma. We find that the resulting hydrodynamic series is divergent in a way consistent with resurgence and precisely encodes information about the nonhydrodynamic modes of the theory.
Malaria Transmission in Bissau, Guinea-Bissau between 1995 and 2012: Malaria Resurgence Did Not Negatively Affect Mortality  [PDF]
Johan Ursing, Lars Rombo, Amabelia Rodrigues, Peter Aaby, Poul-Erik Kofoed
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0101167
Abstract: Introduction As Plasmodium falciparum prevalence decreases in many parts of Sub-Saharan Africa, so does immunity resulting in larger at risk populations and increased risk of malaria resurgence. In Bissau, malaria prevalence decreased from ~50% to 3% between 1995 and 2003. The epidemiological characteristics of P. falciparum malaria within Bandim health and demographic surveillance site (population ~100000) between 1995 and 2012 are described. Methods and Findings The population was determined by census. 3603 children aged <15 years that were enrolled in clinical trials at the Bandim health centre (1995–2012) were considered incident cases. The mean annual malaria incidence per thousand children in 1995–1997, 1999–2003, 2007, 2011, 2012 were as follows; age <5 years 22→29→4→9→3, age 5–9 years 15→28→4→33→12, age 10–14 years 9→15→1→45→19. There were 4 campaigns (2003–2010) to increase use of insecticide treated bed nets (ITN) amongst children <5 years. An efficacious high-dose chloroquine treatment regime was routinely used until artemisinin based combination therapy (ACT) was introduced in 2008. Long lasting insecticide treated bed nets (LLIN) were distributed in 2011. By 2012 there was 1 net per 2 people and 97% usage. All-cause mortality decreased from post-war peaks in 1999 until 2012 in all age groups and was not negatively affected by malaria resurgence. Conclusion The cause of decreasing malaria incidence (1995–2007) was probably multifactorial and coincident with the use of an efficacious high-dose chloroquine treatment regime. Decreasing malaria prevalence created a susceptible group of older children in which malaria resurged, highlighting the need to include all age groups in malaria interventions. ACT did not hinder malaria resurgence. Mass distribution of LLINs probably curtailed malaria epidemics. All-cause mortality was not negatively affected by malaria resurgence.
Reproductive biology of the critically endangered endemic Mediterranean plant Coincya rupestris subsp. rupestris (Spain): the effects of competition and summer drought on seedling establishment
Revista chilena de historia natural , 2008, DOI: 10.4067/S0716-078X2008000300004
Abstract: flower, fruit, seed production, and flowering phenology (duration, intensity, moment and synchrony) were studied in the two main populations (south east spain) of the critically endangered endemic mediterranean plant coincya rupestris subsp. rupestris (cruciferae). production of flowers and fruits (mean ± sd) ranged from 483 (± 688) to 748 (± 636), and from 317 (± 518) to 553 (± 500), respectively, between populations. in addition, the average seed production per plant was 1,607-2,798, thus concluding that fertility was not responsible for the rarity of this taxon. the fruit/flower ratio ranged from 0.60 to 0.75, showing significant inter-population differences. flowering extended from february-march to the end of spring, with high synchrony (= 85 %). this parameter was negatively correlated with duration of the flowering period. the role of pollinator insects on reproductive success, and the effect of watering treatments and the elimination of competitors on seedling recruitment were analysed in the classical locality. the exclusion of pollinators dramatically affected fructification, reducing reproductive success from moderate values in plants exposed to insects (= 0.5) to null values in those where insects were experimentally excluded. seedling emergence was autumnal and no influence of the factors analysed (i.e., water availability and inter-specific competition) was detected on seedling establishment. a high interannual variability in the size and survival of cohorts originated each autumn was observed. it should be emphasized that the rarity of the taxon is not due to fecundity restrictions.
Hydrodynamics, resurgence and trans-asymptotics  [PDF]
Gokce Basar,Gerald V. Dunne
Physics , 2015, DOI: 10.1103/PhysRevD.92.125011
Abstract: The second-order hydrodynamical description of a homogeneous conformal plasma that undergoes a boost- invariant expansion is given by a single nonlinear ordinary differential equation, whose resurgent asymptotic properties we study, developing further the recent work of Heller and Spalinski [Phys. Rev. Lett. 115, 072501 (2015)]. Resurgence clearly identifies the non-hydrodynamic modes that are exponentially suppressed at late times, analogous to the quasi-normal-modes in gravitational language, organizing these modes in terms of a trans-series expansion. These modes are analogs of instantons in semi-classical expansions, where the damping rate plays the role of the instanton action. We show that this system displays the generic features of resurgence, with explicit quantitative relations between the fluctuations about different orders of these non-hydrodynamic modes. The imaginary part of the trans-series parameter is identified with the Stokes constant, and the real part with the freedom associated with initial conditions.
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