Fire tolerance of a resprouting <Emphasis Type="Italic">Artemisia</Emphasis> (Asteraceae) shrub

In North America, most Artemisia (Asteraceae) shrub species lack the ability to resprout after disturbances that remove aboveground biomass. We studied the response of one of the few resprouting Artemisia shrubs, Artemisia filifolia (sand sagebrush), to the effects of prescribed fires. We collected data on A. filifolia density and structural characteristics (height, canopy area, and canopy volume) in an A. filifolia shrubland in the southern Great Plains of North America. Our study sites included areas that had not been treated with prescribed fire, areas that had been treated with only one prescribed fire within the previous 5 years, and areas that had been treated with two prescribed fires within the previous 10 years. Our data were collected at time periods ranging from ½ to 5 years after the prescribed fires. Density of A. filifolia was not affected by one or two fires. Structural characteristics, although initially altered by prescribed fire, recovered to levels characteristic of unburned areas in 3–4 years after those fires. In contrast to most non-sprouting North American Artemisia shrub species, our research suggested that the resprouting A. filifolia is highly tolerant to the effects of fire.     

New Outbreak of <Emphasis Type="Italic">Dendrolimus sibiricus</Emphasis> Tschetv. in Siberia (2012–2017): Monitoring,Modeling and Biological Control

The territory of the new mass outbreak of Dendrolimus sibiricius is northernmost Siberia. The present increase in the pest numbers started in 2011–2012, 14 years after the previous mass outbreak. As a result, the area of damage to dark coniferous forests exceeded 1.4 million ha. The reasons for the emergence of the pest population from a depressive state are insufficient moisture availability in May 2011, severe droughts in June–July 2012, and increased mean monthly temperature. A significant decrease in the vegetation index of SWVI occurred in 2011–2012. The hydrothermal regime of the spring–summer period in these years promoted the transition of most of the pest populations to development over 1-year generation. One exceptional feature of the current outbreak is low damage to D. sibiricus caterpillars by diseases and parasites. Favorable weather conditions and a low number of natural entomopathogens contribute to the rapid spread of the pest in northern and eastern directions. This creates a high risk of mass outbreak of D. sibiricus in dark coniferous forests, since the area of nearby dark coniferous stands suitable in structure, climatic, and forest-growing conditions for the pest dispersal is more than 2.7 million ha. Pure cultures of the entomopathogenic fungus Beauveria bassiana were isolated from dead caterpillars of D. sibiricus. Multistage screening made it possible to select a promising strain for the creation of a long-acting bioinsecticide for the preventive treatment of forests. The main selection criteria are high virulence, high entomopathogenic activity at low temperatures (7–10°C), and the ability for solid-phase fermentation of plant waste.     

Simulations of the Ion Current to a Probe in Plasma with Allowance for Ionization and Ion–Neutral Collisions: II. Cylindrical Probe

The ion current to a cylindrical probe is considered with allowance for volume ionization, ion–neutral collisions, and the ion orbital moment. A model based on the molecular dynamics method and applicable in a wide range of plasma parameters (r_p/λ_D= 0.01–100, r_i/λ_D= 0.002–200, ν_i/ω_0i= 0.01–0.05, and T_i/T_e = 0?0.01) is proposed A convenient representation of the dependence of the relative ion current density on the Langmuir coefficient β² and a technique for determining the plasma density from simulation results are offered.     

Anomalous pinch in the T-11M tokamak in an enhanced-collisionality regime

The formation of a peaked bell-shaped profile of the electron density n _e (r) in the T-11M tokamak (B _t=1 T, R/a = 0.7/0.2 m, I _p = 100 kA, t _shot ≤ 300 ms, Li and C limiters) was observed in Li experiments carried out in the near-plateau collisionality regime (the collisionality parameter at one-half of the minor radius was v* ≥ 0.5) under the conditions of low hydrogen recycling and intense hydrogen influx from the plasma edge. It is well known that peaked n _e (r) profiles are observed in collisionless regimes at v* values as low as 10^?1–10^?2 or in impurity-contaminated discharges, in which this effect can be attributed to the impurity accumulation on the plasma column axis. Moreover, a bell-shaped n _e (r) profile in discharges with low n _e can result from the ionization of hydrogen atoms at the column axis, where they arrive from the plasma edge due to cascade charge-exchange. In quasi-steady lithium discharges in T-11M, however, peaked n _e (r) profiles were observed at a relatively high central electron density n _e (0) and relatively high collision frequency, such that the influence of impurities on the n _e (r) profile could be ignored (Z _eff = 1.1±0.1). To explain this effect, one has to assume that the pinching of hydrogen ions in T-11M is anomalous. The lower estimate of the observed pinch velocity is 4 ± 1 m/s, which is three to five times higher than the velocity of the neoclassical (Ware) pinch, characteristic of these conditions. The work is devoted to the experimental study of this effect.     

A 3D modeling method to calculate the surface areas of coral branches

The quantification of physiological and biochemical parameters in coral branches require normalization to a stable factor, such as the tissue biomass or surface area. Three dimensional (3D) animation software (Gmax^®) was evaluated for estimating the surface area of simple coral branches. The software was highly predictive of the known surface areas of small (20–60 mm long) plastic rods and cones (r ² > 0.99), and of small (30–60 mm) Acropora millepora branches (r ² = 0.98) whose surface area had been obtained using the traditional wax-weight method. Two normalization parameters, 3D modeled surface area and tissue biomass (measured as protein), were then compared for A. millepora branches collected in summer and winter. In winter, protein and surface area were correlated (r ² > 0.61), but not in summer, indicating that choice of normalizing parameter will influence the outcome of experimental analyses.     

Biofilm-associated indole acetic acid producing bacteria and their impact in the proliferation of biofilm mats in solar salterns

Biofilm mats appear in salterns distinctively during the monsoon season when the salinity decreases below 12 percentile salinity units and within a short period cover the entire surface area of the saltern. A study was carried out in two salterns viz. Nerul and Curca to find a possible reason for the rapid proliferation of these solar biofilms. Out of the 125 bacteria isolated from these biofilms, 16 produced indole-3-acetic acid (IAA). Rapid in-situ assay with Salkowski reagent and HPLC analysis confirmed the IAA production. Four isolates consistently produced high IAA concentrations ranging from 9.5 to 14.2 μg/mL in the presence of 4 mg/mL tryptophan concentrations in the growth media. The IAA-producing bacteria were Aeromonas aquariorum (N2), Pseudomonas alcaliphila (N3), Vibrio diazotrophicus (N6) and Pseudomonas pachastrellae (C3). These four IAA-producing bacteria also produced other growth promoting factors like ammonia. Three isolates produced siderophores and were phosphate solubilizers. There was enhancement in the growth of Cicer arietinum (length of the shoot and root) under axenic conditions and of biofilm mats (r = 0.9, p < 0.001; r = 0.8, p < 0.05 and r = 0.946, p < 0.01, respectively). This is, according to our knowledge, the first report indicating IAA-producing bacteria isolated from biofilms enhancing the proliferation of these biofilm mats in the solar salterns.     

Comparison of weight-length relationships and relative growth between intertidal and offshore populations of <Emphasis Type="Italic">Hexaplex trunculus</Emphasis> (Gastropoda: Muricidae) from the Gulf of Gabès (southern Tunisia)

The present study reports weight-length (W-L) relationships and discusses the relative growth of the banded murex (Hexaplex trunculus) from intertidal and offshore areas of the Gulf of Gabès (southern Tunisia). Overall, 9634 H. trunculus were sampled (6608 from intertidal and 3026 from offshore), with both populations comprising broad ranges in shell length (intertidal: 13.6–78.5 mm; offshore: 22.9–91.1 mm) and total weight (intertidal: 0.2–63.8 g; offshore: 0.6–92.5 g). In both populations, W-L relationships were highly significant and the morphometric parameters were highly correlated (intertidal: r?=?0.967; offshore: r?=?0.973). Relative growth was significantly different between populations, with intertidal H. trunculus displaying a negative allometry (b?=?2.962) and offshore H. trunculus exhibiting isometric growth (b?=?3.013). Factors influencing total weight (soft-body weight and shell weight) and potentially responsible for differences in W-L relationships and relative growth between populations were discussed. In addition, a useful comparative analysis for fisheries biology, assessment and management purposes was performed with analogous information from other populations of H. trunculus from the Mediterranean Sea and the Atlantic Ocean.     

Post-release fishing mortality of blue (<Emphasis Type="Italic">Prionace glauca</Emphasis>) and silky shark (<Emphasis Type="Italic">Carcharhinus falciformes</Emphasis>) from a Palauan-based commercial longline fishery

Accounting for components of fishing mortality, including post-release mortality (F_r), is necessary for robust assessments of the effects of fishing. Forty-eight blue (Prionace glauca) and 35 silky sharks (Carcharhinus falciformes) were tagged with pop-up satellite archival tags to monitor F_r rates from pelagic longline vessels in the western tropical Pacific Ocean. There is a paucity of F_r studies at low latitudes and identifying factors that significantly explain F_r is critical for understanding fishing mortality. Mean F_r rates were 0.17 [95% CI 0.09–0.30] for blue shark and 0.20 [95% CI 0.10–0.36] for silky shark. When it occurred, F_r was acute with 87% of mortalities within 2 days of release. Several prognostic operational, environmental, biological and handling variables were evaluated to assess their influence on survival outcomes. Using Kaplan–Meier survival curves, logistic regression, accelerated failure time and Cox proportional hazards models to screen variables, the only significant prognostic or risk variable was health condition at haulback. There was close correspondence (~?83% accuracy) between condition at capture and survival outcomes. Reliable methods to classify at-vessel condition represent an inexpensive and simple metric for estimating both F_r and at-vessel (F_c) mortality rates. Examining F_c rates in detail in longline fisheries using capture information on depth, temperature and dissolved oxygen that may act in synergy with condition code and hooking duration is a research priority. Results suggest that a large proportion of shark survive following release and that F_r rates can be increased by improving the haulback condition of captured sharks.     

Ticks (Acari: Ixodidae) in the Serra da Canastra National Park in Minas Gerais,Brazil: species,abundance, ecological and seasonal aspects with notes on rickettsial infection

The Cerrado Biome is the second largest in Brazil covering roughly 2 million km², with varying features throughout its area. The Biome is endangered but it is also source of animal species for rural, green urban and degraded rainforest areas. Ticks are among Cerrado species that establish at anthropogenic sites and although information about them is steadily increasing, several features are unknown. We herein report tick species, abundance and some ecological relationships within natural areas of the Cerrado at higher altitudes (800–1500 m) within and around Serra da Canastra National Park, in Minas Gerais State Brazil. In total of 1196 ticks were collected in the environment along 10 campaigns held in 3 years (2007–2009). Amblyomma sculptum was the most numerous species followed by Amblyomma dubitatum and Amblyomma brasiliense. Distribution of these species was very uneven and an established population of A. brasiliense in the Cerrado is reported for the first time. Other tick species (Amblyomma ovale, Amblyomma nodosum, Amblyomma parvum, Ixodes schulzei and Haemaphysalis leporispalustris) were found in lesser numbers. Domestic animals displayed tick infestations of both rural and urban origin as well as from natural areas (Rhipicephalus sanguineus sensu lato, Rhipicephalus microplus, Dermacentor nitens, A. sculptum, A. ovale, Amblyomma tigrinum, Argas miniatus). Amblyomma sculptum had the widest domestic host spectrum among all tick species. DNA of only one Rickettsia species, R. bellii, was found in an A. dubitatum tick. Several biological and ecological features of ticks of the studied areas are discussed.     

Effect of high-intensity interval training on muscle remodeling in rheumatoid arthritis compared to prediabetes

Background

Sarcopenic obesity, associated with greater risk of cardiovascular disease (CVD) and mortality in rheumatoid arthritis (RA), may be related to dysregulated muscle remodeling. To determine whether exercise training could improve remodeling, we measured changes in inter-relationships of plasma galectin-3, skeletal muscle cytokines, and muscle myostatin in patients with RA and prediabetes before and after a high-intensity interval training (HIIT) program.

Methods

Previously sedentary persons with either RA (n = 12) or prediabetes (n = 9) completed a 10-week supervised HIIT program. At baseline and after training, participants underwent body composition (Bod Pod^®) and cardiopulmonary exercise testing, plasma collection, and vastus lateralis biopsies. Plasma galectin-3, muscle cytokines, muscle interleukin-1 beta (mIL-1β), mIL-6, mIL-8, muscle tumor necrosis factor-alpha (mTNF-α), mIL-10, and muscle myostatin were measured via enzyme-linked immunosorbent assays. An independent cohort of patients with RA (n = 47) and age-, gender-, and body mass index (BMI)-matched non-RA controls (n = 23) were used for additional analyses of galectin-3 inter-relationships.

Results

Exercise training did not reduce mean concentration of galectin-3, muscle cytokines, or muscle myostatin in persons with either RA or prediabetes. However, training-induced alterations varied among individuals and were associated with cardiorespiratory fitness and body composition changes. Improved cardiorespiratory fitness (increased absolute peak maximal oxygen consumption, or VO₂) correlated with reductions in galectin-3 (r = ?0.57, P = 0.05 in RA; r = ?0.48, P = 0.23 in prediabetes). Training-induced improvements in body composition were related to reductions in muscle IL-6 and TNF-α (r < ?0.60 and P <0.05 for all). However, the association between increased lean mass and decreased muscle IL-6 association was stronger in prediabetes compared with RA (Fisher r-to-z P = 0.0004); in prediabetes but not RA, lean mass increases occurred in conjunction with reductions in muscle myostatin (r = ?0.92; P <0.05; Fisher r-to-z P = 0.026). Subjects who received TNF inhibitors (n = 4) or hydroxychloroquine (n = 4) did not improve body composition with exercise training.

Conclusion

Exercise responses in muscle myostatin, cytokines, and body composition were significantly greater in prediabetes than in RA, consistent with impaired muscle remodeling in RA. To maximize physiologic improvements with exercise training in RA, a better understanding is needed of skeletal muscle and physiologic responses to exercise training and their modulation by RA disease–specific features or pharmacologic agents or both.

Trial registration

ClinicalTrials.gov Identifier: NCT02528344. Registered on August 19, 2015.

     

Association between circulating inflammatory molecules and alcoholic liver disease in men

The association between alcoholic liver disease (ALD) and the inflammatory response remains controversial. The aim of this study was to explore this association between ALD and inflammation. We enrolled 214 male participants, who were divided into three age-matched groups: ALD (n?=?135), chronic alcohol ingestion without ALD (non-ALD; n?=?42), and control (n?=?37). The BMI was significantly higher in the ALD group than in the non-ALD and control groups (all P?=?0.000). Further, the constituent ratio of the liver inflammatory level was significantly higher in the ALD group than in the non-ALD and control groups (P?=?0.002 and P?=?0.000, respectively). In addition, the median serum ALT, AST, and GGT levels were significantly higher in the ALD group than in the control group (P?=?0.023, P?=?0.008, and P?=?0.000, respectively); these levels were also significantly higher in the ALD group than in the non-ALD group (P?=?0.013, P?=?0.010, and P?=?0.000, respectively). The median serum CRP level was significantly higher in the ALD group than in the non-ALD and control groups (P?=?0.006 and P?=?0.000, respectively). Further, the median serum TNF-α level was significantly lower in the ALD group than in the non-ALD and control groups (P?=?0.004 and P?=?0.000, respectively). The median serum sOX40L and HSP70 levels were significantly lower in the ALD group than in the control group (P?=?0.008 and P?=?0.018, respectively). In addition, the ALT, AST, and GGT levels were positively correlated with the CRP level (r?=?0.211, P?=?0.002; r?=?0.220, P?=?0.001 and r?=?0.295, P?=?0.000, respectively), and the GGT level was negatively correlated with the TNF-α (r?=??0.225, P?=?0.001), sOX40L (r?=??0.165, P?=?0.016), and HSP70 levels (r?=??0.178, P?=?0.009). Further, the Cr level was negatively correlated with the IL-10 level (r?=??0.166, P?=?0.015). Logistic regression analysis verified that the BMI (OR??=??1.637, 95%CI: 1.374–1.951, P??=??0.000) and GGT level were significantly higher (OR??=??1.039, 95%CI: 1.020–1.059, P??=??0.000) and that the TNF-α (OR??=??0.998, 95%CI: 0.996–1.000, P??=??0.030) and HSP70 levels were significantly lower (OR??=??1.017, 95%CI: 1.003–1.031, P??=??0.029) in the ALD group than in the non-ALD group. Further, the moderate-to-severe ALD patients had a significantly higher serum CRP level (Or?=???1.349, 95%CI: 1.066–1.702, P??=??0.013) and significantly lower HSP60 (OR??=??0.965, 95%CI: 0.938–0.993, P??=??0.014) and HSP70 levels (OR??=??0.978, 95%CI: 0.962–0.995, P??=??0.010) than the mild ALD patients. These results suggest that ALD patients may present with obesity, liver damage, and an imbalanced inflammatory immune response, mainly manifesting as decreased levels of immune inflammatory cytokines. In addition, they suggest that certain liver and kidney function parameters and ALD severity are either positively or negatively correlated with certain inflammatory cytokines. Hence, ALD patients may be at increased risks of obesity- and inflammation-related diseases. Accordingly, to control the inflammatory response, preventative measures for patients with this disease should include weight control and protection of liver and kidney function.     

Electron density modulation in magnetic islands in the TUMAN-3M tokamak

MHD oscillations with m/n = 4/1 and 3/1 that arise at the periphery of the TUMAN-3M tokamak in the initial stage of a discharge are investigated. It is found that these oscillations lead to a significant modulation of the electron density n _e , which is attributable to the accumulation of plasma within a magnetic island. Numerical simulations of the modulation structure made it possible to determine the radius of the resonant surface and the radial width of the island and to evaluate the characteristic density gradient in the island. The gradient was found to be ten times larger than that of the unperturbed profile of n _e (r) near the resonant surface. This points to reduced plasma transport within the magnetic island.     

Simple generalisation of a mesophyll resistance model for various intracellular arrangements of chloroplasts and mitochondria in C<Subscript>3</Subscript> leaves

The classical definition of mesophyll conductance (g _m) represents an apparent parameter (g _m,app) as it places (photo)respired CO₂ at the same compartment where the carboxylation by Rubisco takes place. Recently, Tholen and co-workers developed a framework, in which g _m better describes a physical diffusional parameter (g _m,dif). They partitioned mesophyll resistance (r _m,dif = 1/g _m,dif) into two components, cell wall and plasmalemma resistance (r _wp) and chloroplast resistance (r _ch), and showed that g _m,app is sensitive to the ratio of photorespiratory (F) and respiratory (R _d) CO₂ release to net CO₂ uptake (A): g _m,app = g _m,dif/[1?+?ω(F?+?R _d)/A], where ω is the fraction of r _ch in r _m,dif. We herein extend the framework further by considering various scenarios for the intracellular arrangement of chloroplasts and mitochondria. We show that the formula of Tholen et al. implies either that mitochondria, where (photo)respired CO₂ is released, locate between the plasmalemma and the chloroplast continuum or that CO₂ in the cytosol is completely mixed. However, the model of Tholen et al. is still valid if ω is replaced by ω(1?σ), where σ is the fraction of (photo)respired CO₂ that experiences r _ch (in addition to r _wp and stomatal resistance) if this CO₂ is to escape from being refixed. Therefore, responses of g _m,app to (F?+?R _d)/A lie somewhere between no sensitivity in the classical method (σ =1) and high sensitivity in the model of Tholen et al. (σ =0).     

Migration of the Northern Boundary of the Siberian Silk Moth

Climate changes have induced the northward migration of outbreaks of the Siberian silk moth (Dendrolimus sibiricus Tschetv.), one of the most dangerous pests in the taiga. The initial outbreak of the Siberian silk moth began in 2014 in Siberian pine.fir stands within the Yenisei Plain on the southwestern flat slopes at elevations up to 200 m above sea level. Further, the outbreak extended to the parts of the forest with higher humidity, the northern slopes, and Yenisei Ridge at low and middle elevations. The northern limit of the outbreak zone shifted to 50 km (to 60°26′ N) northward from the historical boundary of formerly observed outbreaks. The outbreak was incited by an increase in aridity, the sum of positive temperatures (t > +10°C), and a decrease in soil moisture. It extended to an area of 800000 ha. Stand mortality was accompanied by the activation of secondary pests, including aggressive bark beetle species Polygraphus proximus. The outbreak under study is part of the panzonal outbreak that occurred in 2014–2017 on the territory of Siberia in Krasnoyarsk krai and Tomsk, Kemerovo, and Irkutsk oblasts. The increase in warming, aridity, and vegetative period provides opportunities for the Siberian silk moth to migrate to the northern dark-conifer taiga.     

Association of polymorphic markers of chemokine genes,their receptors,and <Emphasis Type="Italic">CD14</Emphasis> gene with coronary atherosclerosis

Atherosclerosis represents an inflammatory response to the disturbance of the endothelial layer in the arterial bloodstream. In the present study, an analysis of associations of polymorphic markers for the genes controlling synthesis of proteins involved in atherosclerosis pathogenesis in coronary atherosclerosis (CA) patients (217 subjects) and in a control group (250 subjects) was conducted. The following genes were examined: rs991804 (CCL2 gene), rs1126579 (CXCR2 gene), rs4074 (CXCL1 gene), rs4073 (CXCL8 gene), rs333 (CCR5 gene), rs2471859 (CXCR4 gene), rs1801157 (CXCL12 gene), and rs2569190 (CD14 gene). Using the Monte Carlo and Markov chain (APSampler) method, allele/genotype combinations associated with both low and high CA risk were revealed. The most important findings included the following: CXCR4*T/T + CCL2*C + CCR5*I/I (P_perm = 1 × 10^–6, OR = 0.44, 95% CI 0.3–0.63), CXCR2*C + CD14*C + CXCL12*G + CCL2*C + CCR5*D (P_perm = 4 × 10^–6, OR = 5.78, 95% CI 2.34–14.28), CD14*C + CCL2*C/C + CCR5*D (P_perm = 6.3 × 10^–6, OR = 5.81, 95% CI 2.17–15.56), CXCL8*A + CXCR2*C + CD14*T + CXCR4*C (P_perm = 0.01, OR = 3.21, 95% CI 1.63–6.31).     

Fen meadows on the move for the conservation of <Emphasis Type="Italic">Maculinea (Phengaris) teleius</Emphasis> butterflies

In the Netherlands, a single population of the obligate myrmecophilic butterfly Maculinea (Phengaris) teleius has survived on only 3 ha of habitat for more than 25 years, whereas at least 40 ha of habitat are thought to be required for a sustainable metapopulation. Therefore, 170 ha of farmland is being restored to wet meadows within a LIFE?+?project by large-scale soil excavation and hay inoculation. For successful restoration, the habitat requirements of the butterfly, with Sanguisorba officinalis as host plant and its particular life cycle as parasite of the ant species Myrmica scabrinodis, have to be taken into account. We tested whether colonization of nests of this ant species in the restoration areas is facilitated by translocation of sods collected from fen meadows. We divided 54 sods, each sized 1 m², randomly over six patches and measured vegetation development and ant presence in the sods and surrounding control plots for 2 years. In the first summer, significantly more Myrmica ants were found in the transplanted sods in comparison to the surrounding area. Herb cover had a significant positive effect on Myrmica ant presence while it did not affect the presence of the pioneer ant species Lasius niger. In the second year, Myrmica ants were found in the surrounding control plots as well. This study contributes to the knowledge-base required for the design of restoration projects aimed at expanding the habitat of the critically endangered butterfly Maculinea (Phengaris) teleius.     

Human-Imposed,Fine-Grained Patch Burning Explains the Population Stability of a Fire-Sensitive Conifer in a Frequently Burnt Northern Australia Savanna

Woody plant demographics provide important insight into ecosystem state-shifts in response to changing fire regimes. In Australian tropical savannas, the switch from patchy landscape burning by Aborigines to unmanaged wildfires within the past century has been implicated in biodiversity declines including the fire-sensitive conifer, Callitris intratropica. C. intratropica commonly forms small, closed-canopy groves that exclude fire and allow recruitment of conspecifics and other fire-sensitive woody plants. C. intratropica groves provide a useful indicator of heterogeneity and fire regime change, but the mechanisms driving the species’ persistence and decline remain poorly understood. We examined the hypothesis that C. intratropica population stability depends upon a regime of frequent, low-intensity fires maintained by Aboriginal management. We combined integral projection models of C. intratropica population behaviour with an environmental state change matrix to examine how vital rates, grove dynamics and the frequency of high- and low-intensity fires contribute to population stability. Closed-canopy C. intratropica groves contributed disproportionately to population growth by promoting recruitment, whereas singleton trees accounted for a larger proportion of adult mortality. Our patch-based population model predicted population declines under current fire frequencies and that the recruitment of new groves plays a critical role in the species’ persistence. Our results also indicated that reducing fire intensity, a key outcome of Aboriginal burning, leads to C. intratropica population persistence even at high fire frequencies. These findings provide insight into the relationship between ecosystem composition and human–fire interactions and the role of fire management in sustaining the mosaics that comprise ‘natural’ systems.     

PCR-based molecular diagnosis of botulism (types C and D) outbreaks in aquatic birds

Clostridium botulinum is a strictly anaerobic spore forming bacterium found in soil and sediments, producing botulinum neurotoxins. Group III strains of this organism are only able to produce neurotoxin types C, mosaic C/D, D/C, and D, which are associated with bird botulism. The threats and outbreak cycle of bird botulism are enhanced in the aquatic environment via a food web-environment-avian interface in response to global climatic changes. The aim of this review was to describe and discuss the development of PCR-based markers, diagnostic assays, and applications with special emphasis to botulism detection in aquatic birds. We employed a text-mining approach for collection of current diagnostic information to bird botulism in aquatic environments. Using the PubMed search engine, we have comprehensively collected relevant information from 124 articles and then summated for the purpose of this review. Genes coding for botulinum neurotoxin (bont/C, bont/C/D, bont/D/C, and bont/D), nontoxic components (ha70, ha17, ha33, and ntnh), and flagellin (fliC) were the molecular markers most commonly found for the genotyping of group III strains from environmental samples. “GeneDisc” real-time PCR system was a robust and reliable diagnostic technique for discrimination of neurotoxin types in the large sampled areas. PCR-based assays were the most perceptive and widely established for detection of bird botulism, even if several biochemical and molecular diagnostic techniques have been available. Thus, timely and accurate identification of its mortality is needed to provide a biosecurity, disease control management, and conservation of aquatic birds. PCR-based diagnosis is a promising alternative to the mouse bioassay. Hence, the present paper makes an attempt to review the PCR-based detection assays including primers, specificity, sensitivity, and detection limit and explore their potential applications in wildlife microbiology.