bluuebunny/crossref_metadata_2025 huggingface dataset:
Rat‐bite fever identified by polymerase chain reaction detection of Streptobacillus moniliformis DNA
Authors: NAKAGOMI Daiki , DEGUCHI Nobuhiro , YAGASAKI Akiko , HARADA Kazutoshi , SHIBAGAKI Naotaka , KIMURA Masanobu , IMAOKA Koichi , SHIMADA Shinji
Published: September 2010

A 74‐year‐old woman presented with erythema of the extremities, a high fever and arthralgia after being bitten by a rat. The patient was diagnosed as having rat‐bite fever based on the symptoms and clinical course, as well as the polymerase chain reaction detection of Streptobacillus moniliformis DNA in the crust of the bite site. This is the first case to be diagnosed using polymerase chain reaction on a crusted skin lesion specimen. Although clinical symptoms initially remitted with minocycline therapy, they relapsed. Subsequent administration of piperacillin sodium resulted in complete disappearance of the high fever and arthralgia.
Serum levels of interleukin‐8, tumor necrosis factor‐α and γ‐interferon in Egyptian psoriatic patients and correlation with disease severity
Authors: ABDEL‐HAMID Mahmoud F. , ALY Dalia G. , SAAD Nevine E. , EMAM Hanaa M. , AYOUB Dina F.
Published: September 2010

Psoriatic plaques have been shown to contain increased levels of pro‐inflammatory cytokines. Also, serum levels of several cytokines have been reported elevated in psoriatic patients. It is postulated that changes in cytokine production both locally and systemically could be useful in monitoring disease activity. The aim of this study was to evaluate serum cytokine profile of interleukin (IL)‐8, γ‐interferon (IFN‐γ) and tumor necrosis factor‐α (TNF‐α) in Egyptian psoriatic patients by enzyme‐linked immunosorbent assay (ELISA) technique and to correlate these levels with disease severity. We analyzed serum samples from 60 Egyptian patients (31 females and 29 males) with a mean age of 40.2 ± 17.4 years with active psoriasis, and 21 healthy volunteers for major T‐helper type 1 cytokines using the ELISA technique. The disease severity, including erythema, induration and scales, was assessed by Psoriasis Area and Severity Index (PASI) score. TNF‐α and IFN‐γ were markedly elevated in all sera from psoriatic patients. TNF‐α was found a more efficient predictor for disease severity than IL‐8 and IFN‐γ using three receiver–operator curves with accuracy. IL‐8 was also moderately elevated and correlated with the age of patients (r = 0.28). We have obtained evidence that TNF‐α in our study was found to be more useful than the other two tested cytokines, IL‐8 and IFN‐γ as a follow‐up marker for monitoring disease severity in Egyptian psoriatic patients. A positive correlation between lL‐8 and the age of the patients was also noted.
Which came first: the readiness or the change? Longitudinal relationships between readiness to change and drinking among college drinkers
Authors: Collins Susan E. , Logan Diane E. , Neighbors Clayton
Published: September 2010

Aims  Although readiness to change (RTC) is cited as a key mechanism underlying drinking behavior change, empirical evidence supporting RTC as a predictor of college drinking has been mixed. Considering methodological limitations of previous studies, the current aim was to conduct a more comprehensive test of longitudinal relationships between readiness to change and college drinking.

Design  In this correlational, longitudinal study, we used a series of cross‐lagged path analyses to test associations between RTC and college drinking outcomes over a 2‐year period.

Setting  Data collection was conducted via online surveys on a university campus in the US Pacific Northwest.

Participants  Participants (n = 818; 58% women) were college students who reported at least one heavy‐drinking episode in the past month and participated in a randomized controlled trial of personalized normative feedback interventions.

Measurements  Drinking quantity–frequency items and the Rutgers Alcohol Problem Index assessed drinking outcomes. The Readiness to Change Questionnaire assessed RTC.

Findings  For drinking‐related problems, the best‐fitting model included cross‐lagged paths between RTC and subsequent drinking‐related problems. For drinking quantity–frequency, best‐fitting models also included the cross‐lagged paths between drinking quantity–frequency and subsequent RTC. Higher RTC almost uniformly predicted higher subsequent levels of drinking and greater experience of drinking‐related problems, and drinking quantity–frequency variables were primarily positive predictors of subsequent RTC.

Conclusions  Contrary to previous assumptions, ‘the Readiness to Change Questionnaire’ does not appear to be predictive of lower levels of subsequent drinking.
Recruitment sources for fish stocks inside a floodplain river impoundment in Bangladesh
Authors: HOGGARTH D. D. , DAM R. K. , DEBNATH K. , HALLS A. S.
Published: September 2010

Abstract The sources of fish recruitment in the hydrologically modified, impounded Pabna Irrigation and Rural Development Project (PIRDP) flood control and irrigation scheme in NW Bangladesh were investigated. Catches at sluice gates were analysed to determine the migratory behaviour of fish. Fish attempted to migrate through the undershot sluice gates when they were opened, both with and against the currents, and both in and out of the PIRDP. Many fish were caught by the fishermen at such locations, but it is argued that some fish were probably able to enter the PIRDP from outside. One to two percentage of fish survived the dry season at the PIRDP, mostly in the deeper, perennial water bodies, both in rivers and lakes, and both inside and outside the flood control scheme. Fewer species survived inside the scheme, and the numbers of species remaining declined as the dry season progressed. It was shown in companion papers that fish production inside the PIRDP was lower than outside in both 1995 and 1996 even though the growth and reproductive potential of individual fish were at least as good inside as outside. The apparently negative impact of the PIRDP was explained by the reduced accessibility of the scheme to some migrant fish, as reflected by the inside/outside species compositions. It was concluded that fish catches within the PIRDP are sustained mainly from recruits produced by residing annual populations, while the biodiversity of the stocks was augmented by limited recruitment of fish migrating through the sluice gates from external sources. Two management approaches were proposed for increasing recruitment to the impounded PIRDP fishery as cheap alternatives to fish stocking: the use of dry season reserves to protect the residing spawning stocks; and the management of flood control sluice gates to maximise recruitment from external sources.
Threshold values of river discharge and temperature for anglers' catch of Atlantic salmon, Salmo salar L.
Authors: L'ABÉE‐LUND J. H. , ASPÅS H.
Published: September 2010

Abstract The catch by anglers of adult Atlantic salmon, Salmo salar L., was studied over a 5‐year period in the River Gaula, Norway. Atlantic salmon were caught over a wide range (23–570 m3 s−1) of the observed extent of river discharge (13–950 m3 s−1) and throughout the range of temperature (4–23 °C), but both factors strongly affected catch rate. Significant correlations between the number of Atlantic salmon caught daily, and water temperature (r = 0.33) and river discharge (r = −0.42) were found in 1987 and 1989, respectively. The highest daily catch occurred between 50 and 150 m3 s−1, and at temperatures between 13 and 16 °C. Threshold values for water discharge and temperature were found to exist at 250 m3 s−1 and 8 °C, with the highest catches below and above these values, respectively.
Pattern and prevalence of predator damage on adult Atlantic salmon, Salmo salar L., returning to a river system in north‐east Scotland
Authors: THOMPSON P. M. , MACKAY F.
Published: September 2010

Abstract There remains considerable debate over the impact of predation upon Atlantic salmon, Salmo salar L., populations. The pattern and prevalence of predator damage on salmon returning to a river system in North‐east Scotland were recorded. Overall, 214 (19.5%) out of 1099 fish sampled were damaged, and 10 distinct categories of damage were identified. Measurements of scratches indicated that the damage was caused by a number of different factors. In particular, damage typically attributed to seals was suggested to be the result of attacks by odontocete cetaceans. These results highlight the multispecies nature of interactions between salmon and their predators, but suggest that damage levels may be of limited use in assessing the impact of different predators on salmonid population dynamics.
Factor XI deficiency and its management
Authors: SMITH J. K.
Published: September 2010

The meeting offered participants, mostly interested in the manufacture or clinical application of factor XI concentrates, an opportunity to review evidence of their efficacy and some recent concerns about their safety.
Successful treatment of acute subdural haemorrhage with continuous intravenous infusion of factor VIII in a 17 year old with haemophilia A
Authors: RICHARDSON N. G. B. , MILLER A. L. , O'SHAUGHNESSY D. F.
Published: September 2010

Intracranial haemorrhage is a common complication of haemophilia, occurring in 2–8% of sufferers [1]. Half of the cases give a history of trauma and despite developments in the management of acute bleeding the condition still carries a mortality of approximately 30% [2]. Surgery may be required, most commonly for evacuation of a subdural haematoma which carries a mortality of up to 40% [3].

We present the case of a 17‐year‐old haemophiliac with a traumatic subdural haemorrhage, who was treated with a continuous intravenous infusion of factor VIII and made a complete recovery without recourse to surgery. We have found no reference in the world literature of such treatment for acute subdural haemorrhage in a haemophiliac.
Comparison of two sonic handpieces during the preparation of simulated root canals
Authors: DUMMER P. M. H. , HUTCHINGS R. , HARTLES F. R.
Published: September 2010

The objective of this study was to assess and compare two sonic handpieces during the preparation of simulated root canals. A total of 60 simulated canals in clear resin blocks of various angles and positions of curvature were prepared using Shaper files activated either by an MM1500 Sonic Air or an MM1400 Mecasonic hand‐piece. Each handpiece was used to prepare 30 canals using an identical preparation procedure which involved a linear filing motion and an anticurvature technique in curved canals. The efficacy of the handpieces was determined for straight and curved canals separately and included an assessment of loss of canal length, weight loss from the blocks, smoothness of canal walls, transportation and overall shape of the prepared canals. Canals were prepared rapidly and effectively by both handpieces. Overall, the MM 1500 handpiece was associated with significantly less distance loss (P< 0.05) and significantly more loss of weight (P<0.01). Only four prepared canals (8%) had hour‐glass shapes displaying zips and elbows, each handpiece created two. Only two canals (4%) had danger zones, both were created by the MM1400 handpiece. There was little difference between the handpieces in terms of the smoothness of canal walls, the direction and amount of transportation or the overall shape of canals. Under the conditions of this study, the new MM1400 Mecasonic handpiece performed as well as the established MM 1500 Sonic Air.
An assessment of the plastic Thermafil obturation technique
Authors: SAUNDERS W. P. , SAUNDERS E. M. , GUTMANN J. L. , GUTMANN M. L
Published: September 2010

The effect of post space preparation on the apical seal of teeth roots treated with the plastic‐cored Thermafil was studied in vitro. Single rooted teeth with mature apices were prepared chemomechanically and obturated with alpha‐phase gutta‐percha, Thermafil, on plastic corecarriers and sealer, Sealapex. The teeth were divided randomly into four groups of 18 teeth each. In two of the groups post space was prepared by hand using a Parapost drill (diam. 1.25 mm) after gutta‐percha removal with Peeso reamers in a slow‐speed handpiece, one group immediately after canal obturation and the other after storage in 100% relative humidity at 37°C for 1 week; 5 mm of root filling was left intact. The time taken to remove the gutta‐percha was recorded. Post space was not prepared in the control groups. Apical leakage was determined using black India ink. The teeth were demineralized, rendered transparent, and linear measurement of dye penetration was recorded. Results showed that there were no significant differences in leakage between any of the groups (P> 0.05). There was no statistically significant difference in the time required to remove the gutta‐percha from the root canals in both groups (P<0.05). It is concluded that under the conditions of this study post space preparation immediately after obturation, or after a delay of 1 week, does not affect the apical seal of Thermafil with plastic corecarriers.
Effects of nutrient enrichment on predator–prey metapopulation dynamics
Authors: Holyoak Marcel
Published: September 2010

1. In certain predator–prey models, enrichment of nutrients produces large amplitude population oscillations that can cause extinctions; this effect has been termed the ‘paradox of enrichment’. Metapopulation models also show that despite enrichment reducing the stability of equilibria in local populations, spatially subdivided populations may show bounded fluctuations because of asynchronous local density fluctuations.

2. Effects of enrichment and subdivided habitat structure were tested using two protozoans, predatory Didinium nasutum Müller and its bacterivorous prey, Colpidium striatum Stokes. A replicated experiment compared predator–prey dynamics in low, medium and high nutrient microcosms. Microcosms consisted of subdivided arrays of nine interconnected 30 mL bottles, undivided bottles of the same total volume (270 mL) and isolated 30 mL bottles.

3. Consistent with the paradox of enrichment, isolated populations produced greater mean predator densities at high nutrient concentrations than low or medium concentrations. The proportion of replicates in which predators drove prey extinct was also greater with high than with low or medium nutrient concentrations.

4. Enrichment increased prey density in all microcosm types. This is consistent with published predator–prey models where dynamics are mathematically unstable.

5. Predators and prey persisted longer in all subdivided microcosms than in undivided bottles. However, there were some unexpected changes in spatial dynamics with enrichment. For prey, direct or indirect effects of enrichment raised numbers dispersing, spatial synchrony of density fluctuations and variability in the number of patches occupied.

6. For predators in arrays, enrichment reduced the starvation rate, total numbers dispersing, and spatial synchrony. Time until recolonization of individual patches by predators was also longer in enriched microcosms, suggesting a possible decrease in the likelihood of regional persistence. A published simulation model produced qualitatively similar changes in dynamics with changes in prey and predator dispersal rate.

7. This study shows that spatial dynamics can potentially explain persistence of subdivided populations for long periods despite nutrient enrichment. However, the complex influence of enrichment on spatial dynamics illustrates the need to study more natural populations.
Geographic distance and the role of island area and habitat diversity in the species–area relationships of four Lesser Antillean faunal groups: a complementary note to Ricklefs & Lovette
Authors: Morand Serge
Published: September 2010

1. Recently,Ricklefs & Lovette (1999)have emphasized the possible confounding effect of habitat diversity on area while studying species–area relationships. They illustrated this problem using four groups of organisms (birds, bats, herptiles, and butterflies) on 19 islands of the Lesser Antilles. Although they referred to the potential for species to migrate between islands, they did not take into account the geographical distances between islands.

2. Here, I reanalyse their data using a multivariate method, based on permutation of distance matrices, which incorporates pairwise geographical distances between islands. The analysis includes as independent variables the geographical distances between pairs of islands, size, maximum elevation, and habitat diversity of each island. The last three variables were obtained fromRicklefs & Lovette (1999).

3. Results of the analysis were similar to those ofRicklefs & Lovette (1999). In addition, however, geographical distances influenced species richness of bats, birds and butterflies.

4. These new results are helpful for investigating the processes that may contribute to the observed pattern of species richness. The level of endemism of the four taxonomic groups is related to the influences of geographical distances among islands, and might be explained by differences in their vagility.

5. Finally, I emphasize the need to incorporate geographical distances among islands, using statistical methods that can manipulate distance matrices.
Silver spoons and snake body sizes: prey availability early in life influences long‐term growth rates of free‐ranging pythons
Authors: Madsen Thomas , Shine Richard
Published: September 2010

1. A 13‐year study of free‐ranging water pythons (Liasis fuscus) and their main prey (dusky rats, Rattus colletti) in tropical Australia provided extensive data on the relationship between python growth rates and prey availability.

2. Python growth rates exhibited considerable variation among individuals. Growth rates of siblings were not correlated, suggesting that environmental rather than genetic factors cause this wide variation.

3. The availability of prey varied considerably among years, due to annual variation in rainfall patterns. Pythons grew more rapidly in years with high rat abundance than in years when rats were scarce. Also, python cohorts that hatched in years when prey were abundant exhibited faster growth rates than those that hatched when prey were scarce.

4. The snakes showed strong ontogenetic consistency in relative growth rates: that is, an individual with faster‐than‐average growth in its first year of life continued to grow rapidly throughout the study period. Thus, these pythons displayed a strong ‘silver spoon’ effect, whereby favourable conditions (high prey abundance) in the first year of life exerted a long‐term effect on growth trajectories and thus, adult body sizes. This effect was strongest in the faster‐growing sex (females).

5. Hence, the current body size composition of the python population reflects stochastic rainfall‐induced annual variation in prey availability over the preceding decades.
Factors affecting first‐year survival in grey seals and their implications for life history strategy
Authors: Ailsa J. Hall , Bernie J. McConnell , Richard J. Barker
Published: September 2010

In order to estimate the effect of weaning mass and body condition on the post‐weaning survival of grey seal pups from the Isle of May, Scotland in 1998 during their first year of life, a simultaneous analysis of live resighting and dead recovery mark–recapture data was used. A new type of tag was employed which allowed individuals to be identified when resighted alive (Hall, Moss & McConnell 2000) as well as when found dead.

The probability of post‐weaning survival to age 1 increased with body condition at weaning and differed between the sexes. Regardless of pup condition and time of year, the odds of survival for female pups over a 2‐month interval was estimated to be 3·37 (SE = 1·30) times higher than for males. Regardless of sex, a 1 standard deviation increase in pup condition was estimated to increase the odds of survival by a factor of 1·422 (SE = 0·226). For a male pup in average condition (0·41 kg cm−1) the estimated annual survival after adjusting for tag‐loss was 0·193 (SE = 0·084); for a female pup in average condition (0·39 kg cm−1) it was 0·617 (SE = 0·155).

The effect of condition at weaning on survival was significantly greater for male pups than for females. This implies that high quality females should invest more heavily in their male pups because the marginal return, in terms of increased reproductive value, from any additional expenditure is twice that for females. Male pups in our sample were significantly heavier at weaning and in better condition than female pups. However, this does not provide conclusive support for our predictions, because we could not control for the effects of maternal size on weaned mass.
Climate change and breeding success: decline of the capercaillie in Scotland
Authors: Moss Robert , Oswald James , Baines David
Published: September 2010

The number of capercaillie in Scotland has fallen since the 1970s. Previous work showed that low breeding success, exacerbated by deaths of fully grown birds flying into forest fences, was the primary cause of the decline. The hypothesis that climate change caused the lower breeding success was investigated in this study.

Temperature usually rose during April. There was no trend in mean April temperature during the study (1975–99) but there was a progressive cooling in mid‐April relative to the rest of the month, such that the normal April warming was increasingly delayed.

Hens reared more chicks when the temperature rose more in early April. It is suggested that this stimulated timely plant growth, so improving the laying hens’ plane of nutrition and the viability of their chicks.

Hens also reared more chicks when late May was warmer and early June was warmer and had fewer rain days. Young chicks may have foraged more successfully in warm dry conditions. However, neither temperature nor rain days in late May or early June showed any trend during the study.

Increasingly protracted spring warming seems to have been a major cause of the decline of the capercaillie in Scotland.
Ungulate foraging strategies: energy maximizing or time minimizing?
Authors: Bergman Carita M. , Fryxell John M. , Gates C. Cormack , Fortin Daniel
Published: September 2010

Many classical models of ungulate foraging are premised on energy maximization, yet limited empirical evidence and untested currency assumptions make the choice of currency a non‐trivial issue. The primary constraints on forage intake of ungulates are forage quality and availability. Using a model that incorporates these two constraints, we predicted the optimal biomass of forage patches for ungulate grazers using an energy maximizing vs. a time minimizing strategy.

 We tested these predictions on wood bison (Bison bison athabascae Rhoads) grazing naturally occurring sedge (Carex atherodes Spreng). The digestive constraint was determined by a series of ad libitum feeding trials using sedge at different stages of growth. Sedge digestibility declined with biomass. Ad libitum intake of sedge by bison declined with sedge digestibility and thus decreased with sedge biomass. On the other hand, short‐term sedge intake rates of wood bison increased with biomass.

 Incorporation of these constraints resulted in the prediction that daily energy gain of bison should be maximized by grazing patches with a biomass of 10 g m−2, whereas a bison could minimize daily foraging time needed to fulfil its energy requirement by cropping patches with a biomass of 279 g m−2.

 To test these quantitative predictions, we used a staggered mowing regime to convert even‐aged stands of sedge to a mosaic of patches varying in quality and quantity. Observations of bison grazing these mosaics indicated that patches of biomass below 120 g m−2 were avoided, while patches of biomass 156 and 219 g m−2 were highly preferred, with the greatest preference for the latter.

 These results indicate that bison were behaving as time minimizers rather than energy maximizers. Daily cropping times of free‐ranging bison from the literature corroborate our results.
A high harvest rate induces a tendency to generation cycling in a freshwater fish population
Authors: HUUSKO ARI , HYVÄRINEN PEKKA
Published: September 2010

The dynamics of exploited populations are clearly affected by two major processes, recruitment and harvesting. The large variation in recruitment is caused mainly by the variation of the brood stock size, which links at least partly to harvesting and consequently is under anthropogenic control. Therefore, harvesting has the potential to modulate the dynamics of exploited populations in many ways.

Demonstrated by a pelagic planktivore fish, vendace Coregonus albula L., using population dynamics in Lake Oulujärvi, northern Finland, this study shows that the changes in harvesting induced a tendency to generation cycling in the dynamics of a freshwater fish population.

The relatively long‐term oscillation in recruitment and stock dynamics of the vendace population transformed into clear 2‐year cycling in recruitment and also into the same tendency in the spawning stock, both induced by the increase of the harvest rate to a high and stable level. The high harvest rate evidently simplified the spawning population structure from a multigeneration state to an almost totally single‐generation state, followed by generation cycling in the population dynamics.

The results demonstrated clearly that harvesting can work as forcing agent and actually dictate the population fluctuations. It is very important to be aware of how natural variations in population abundance interplay with harvesting and also with other human actions. All these support a precautionary policy in harvesting and stress the importance of understanding the basic mechanisms of population dynamics in order to gain sustained yields from the population in space and time.
Planning for success: Serengeti lions seek prey accessibility rather than abundance
Authors: HOPCRAFT J. GRANT C. , SINCLAIR A. R. E. , PACKER CRAIG
Published: September 2010

We used long‐term radio‐telemetry data to investigate how Serengeti lions (Panthera leo) distribute themselves with respect to hunting opportunities. Specifically, we investigate whether lions hunt in areas where prey are easy to capture or where prey are locally abundant.

We used resource‐selection functions (logistic regressions) to measure the location of kills/carcasses with respect to five different habitats: the view‐sheds from large rocky outcrops, river confluences, woodland vegetation, erosion embankments and water sources.

As expected for a sit‐and‐wait predator, resting lions spent more time in areas with good cover. On a broad‐scale, lions shifted their ranges according to the seasonal movement of prey, but at a finer scale (< 100 m) lions fed in areas with high prey ‘catchability’ rather than high prey density. Plains lions selected erosion embankments, view‐sheds from rocky outcrops, and access to free water. Woodland lions tended to use erosion embankments, and woody vegetation.

The results emphasize the importance of fine‐scale landscape and habitat features when assessing predator–prey theory and conservation.
Does interspecific competition from congeners cause the scarcity of Gerbillus henleyi in productive sandy desert habitats?
Authors: ABRAMSKY Z. , ROSENZWEIG M. L. , ELBAZ M. , ZIV Y.
Published: September 2010

We tested the hypothesis that Gerbillus henleyi (de Winton 1903), the smallest species (10 g) of a pssamophilic guild in Israel, is scarce on relatively productive dunes of the Israeli desert, due to negative interactions from the common G. allenbyi (Thomas 1918) and G. pyramidum (Geoffroy 1825).

The alternative hypothesis was that scarcity on sand resulted from the size of its naked hind feet, that do not allow efficient locomotion on sand.

Despite their naked soles the weight‐bearing surface of G. henleyi feet carry less mass/area than those of any other species.

We measured interaction coefficients with the two common species using field‐manipulation experiments in two enclosures.

Habitat usage of G. henleyi changed from significantly preferring the stabilized sand, when alone, to significantly using the semistabilized dune, when G. allenbyi was also present.

We also estimated the interaction coefficients and calculated the G. henleyi's isoclines competing with the two common gerbil species using a technique we developed elsewhere.

The stability analysis of the isoclines of G. henleyi competing with either G. allenbyi or with G. pyramidum suggests that stable coexistence occurs when G. henleyi is relatively scarce while the competitors are common.

Interspecific competition from either G. allenbyi or G. pyramidum accounts for 90·3% reduction in G. henleyi density, relative to when it is alone.

We concluded that the negative interactions from congeners was the major cause for the scarcity of G. henleyi on the relatively rich sand dunes of the Israeli desert.
The effect of host odour on the landing responses of tsetse flies (Glossina morsitans morsitans) in a wind tunnel with and without visual targets
Authors: BURSELL E.
Published: September 2010

Abstract The effect of artificial host odour on the landing responses of males of Glossina m.morsitans West, and on their reaction to visual targets has been investigated in a wind tunnel. Landing was induced in flies that traversed steep odour gradients as they flew upwind and downwind across the edge of an odour plume, irrespective of whether visual targets were present or not; the landing response could be elicited over a wide range of odourconcentrations. When targets were present such odour gradients also tended to increase the proportion of landing flies which alighted on or near the targets; and the bigger the target, or the hungrier the flies, the greater was the propensity for target landing. In air which was more uniformly permeated with odour, the propensity to land on targets was increased only at high odour concentration.
Fast axon activity and the motor pattern in cockroach legs during swimming
Authors: COCATRE‐Z1LGIEN J. H. , DELCOMYN F.
Published: September 2010

Abstract Electromyographic recordings were made from muscles that extend the trochanter/femur of each of the six legs of American cockroaches, Periplaneta americana (L.), while the insects swam in water. The recordings showed two novel features. (1) During swimming, muscle activity in different legs was coordinated in the alternating tripod pattern commonly seen during free walking on land, not in the pattern of synchronous leg pairs common to other large terrestrial insects in water. (2) Fast axons were usually recruited along with slow axons, even when the insect swam at a moderate pace. Fast axon activity always started after the middle of the slow axon burst in intact insects, but vanished from most bursts in the stump of the leg after amputation of the femur. The alternating tripod pattern was maintained even after amputation. Possible causes of fast axon recruitment are discussed.
Feeding frequency in relation to reproduction in Glossina morsitans morsitans and G.pallidipes
Authors: LANGLEY P. A. , STAFFORD K.
Published: September 2010

Abstract Measurements of residual haematin in males of Glossina morsitans morsitans Westwood reared in the laboratory at 25oC suggest that blood meal digestion is completed in 4 or 5 days after feeding. However, a high proportion of haematin is present as faecal matter 2 days after feeding and it is concluded that digestion is completed sooner than indicated by the regression of logio haematin on time. Therefore, low levels of residual haematin in field‐caught tsetse provide no indication of the frequency with which they feed. For this reason the effects of feeding frequency upon various reproductive parameters in the laboratory have been examined. It is concluded that the best performance is achieved by G.m. morsitans females which ingest four blood meals per inter‐larval period and that for a similar performance in G.pallidipes five blood meals are required. The extent to which such feeding frequencies are a reflection of feeding activity in the field are discussed in terms of the biochemical requirements to maintain a reproductive adult female tsetse in positive energy balance.
Rhythmicity of sex pheromone content in female Heliothis virescens: impact of mating
Authors: MBATA GEORGE N. , RAMASWAMY SONNY B.
Published: September 2010

Abstract Pheromone production in virgin females of Heliothis virescens (F.) (Lepidoptera: Noctuidae) peaked between the fourth and seventh hours of scotophase on the second, third, fourth and fifth days following eclosion. The highest peak (186 ng) occurred on day 3 after eclosion. Z‐11‐Hexadecenal comprised the highest proportion of seven components in the pheromone glands. Disproportionately higher amounts of hexadecanal and Z‐11‐hexadecenol occurred during photo‐phase and other periods when low quantities of total pheromone were recorded.

Mating suppressed pheromone production which remained low until 48 h after mating. Coupling females with males mated three times previously or with 6‐day‐old males was less effective in causing a drop in pheromone content which peaked again 24 h after mating. This suggests the transfer of a male factor, a pheromonostatic factor, that suppresses pheromone production in mated females and that the factor from older and previously mated males is less effective.
The orientation inducer pheromone of the fire ant Solenopsis invicta
Authors: MEER ROBERT K. VANDER , LOFGREN CLIFFORD S. , ALVAREZ FRANCISCO M.
Published: September 2010

Abstract Foraging ants recruit nestmate workers to food sources by a variety of mechanisms. We report that one behavioural subcategory of the recruitment pheromone complex of Solenopsis invicta Buren involves orientation induction. The orientation inducer pheromone exerts its effects by changing the physiological state of the recipient rather than by releasing a measurable behaviour. Some ant species use a physical ‘waggle’ behaviour to motivate (change physiological state) nestmate workers to follow their chemical trail. The orientation inducer pheromone can be interpreted as a chemical analogue of the physical ‘waggle’ inducing effects. This behaviour is not elicited by the recruitment pheromone components responsible for orientation and/or attraction. Each of these behavioural categories is mediated by a different blend of chemicals from the Dufour's gland. Activity‐concentration thresholds indicate that the attraction and inducer part of the recruitment pheromone require about 250 times more worker equivalents for a response than the orientation pheromone. Therefore, the recruitment sub‐categories are differentially activated by the amount of Dufour's gland material released.
Effects of sublethal dose of chlorfluazuron on testicular development and spermatogenesis in the common cutworm, Spodoptera litura
Authors: Perveen Farzana
Published: September 2010

This paper describes the physiological mechanism of action of chlorfluazuron on testicular development and spermatogenesis when sublethal doses (LD10: 1.00 ng/larva or LD30: 3.75 ng/larva) are applied topically to the cuticle of newly moulted fifth instars of the common cutworm Spodoptera litura (F.) (Lepidoptera, Noctuidae). These doses disrupt the growth and development of testes by decreasing the volume and weight of testes and thickness of testes sheath as compared with that of the controls. Sublethal doses of chlorfluazuron also significantly reduce the protein content of the testis, but do not affect the carbohydrate and lipid contents in newly emerged treated males when measured in μg/mg of testis as compared with that of the controls. Additionally, such doses disrupt spermatogenesis by reducing the number and size of eupyrene and apyrene sperm bundles in the testis. Very few or no eupyrene sperm bundles are observed in vas deferens of pre‐ and newly moulted adults compared with controls. This result shows that the transfer of sperm bundles from testes to vas deferens is delayed in treated males. The effects of chlorfluazuron on testicular development and spermatogenesis is thought to be one of the factors responsible for the reduction in fecundity, fertility and hatchability caused by sublethal doses of chlorfluazuron.
Locust flight initiation: a comparison of normal and artificial release
Authors: Kutsch W. , Fuchs U.
Published: September 2010

Flight initiation was analysed in the migratory locust,Locusta migratoriaL. using conventional and high‐speed video systems. Flight was initiated by three methods: normal jump, free fall and controlled catapult.

Parameters evaluated were time from release to wing‐opening, body angle, speed, height gain, wing‐opening, initial wing‐beat frequency. Fastest wing‐opening occurred following a normal jump. A catapult device allowed manipulation of the launching parameters: speed and angles at launching. It appeared that in an artificially catapulted start there was a minimum speed (v > 0.75 m/s) required to initiate flight. However, under free‐fall conditions a mean speed of v = 0.6 m/s at wing‐opening was observed. When the different parameters of the controlled catapult start were equal to those for normal jump then the time to wing‐opening was found to be extended for the catapult launch. However, other parameters were not affected, occasionally even a ‘kick in air’ was observed. The catapult launches indicated that within about three wing‐beat cycles the animals showed active flight, with positive lift and constant or increasing speed, compared to a ballistic trajectory. Our results indicate that a controlled catapult device will prove useful to the study of sensory and central processes underlying free flight initiation.
Oviposition‐stimulatory activity of phenanthroindolizidine alkaloids of host‐plant origin to a danaid butterfly, Ideopsis similis
Authors: Honda Keiichi , Ômura Hisashi , Hayashi Nanao , Abe Fumiko , Yamauchi Tatsuo
Published: September 2010

Oviposition response of Ideopsis similis (L.) (Lepidoptera: Danaidae) was examined for 12 phenanthroindolizidine alkaloids present in its host plant, Tylophora tanakae (Maxim.) (Asclepiadaceae). At least five alkaloids, i.e. (+)‐isotylocrebrine (3,4,6,7‐tetramethoxyphenanthroindolizidine; l), (+)‐3‐demethyliso‐ tylocrebrine (3), (+)‐isotylocrebrine N‐oxide (5), (+)‐6‐demethyltylocrebrine (8) and (–)‐7‐demethyltylophorine (10), were found to individually stimulate oviposition by females. Of these, compounds 1, 3 and 10 were regarded as key components most responsible for host recognition or preference. However, female egg‐laying was much higher in response to a mixture of the five alkaloids. In two‐choice bioassays, more eggs were deposited on samples comprising the five alkaloids than on samples consisting of a single alkaloid. This suggests strongly that host selection by the butterfly is mediated by the synergistic action of several phenanthroindolizidine alkaloids present in the host plant.
Quantification of cockroach allatostatin‐like peptide and its myotropic effects in males of the earwig Euborellia annulipes
Authors: Phitayakorn Roy , Bennett Gregory P. , Rankin Susan M.
Published: September 2010

A monoclonal antibody to allatostatin I of the cockroach Diploptera punctata was used to establish a competitive enzyme‐linked immunosorbent assay for quantification of allatostatin‐like peptides in the hindgut of the adult male earwig, Euborellia annulipes. Hindguts of 0‐day males contained significantly more allatostatin‐positive material than those of 8‐day males fed on catfood. However, males starved for the first 8 days of adult life had significantly higher levels of allatostatin‐positive material than those of either 0‐day or of 8‐day fed males.

Hindguts from 0‐day old males exhibited lower spontaneous motility in vitro than those from 8‐day males. Hindguts from males at both ages responded to allostatin with reversible, dosage‐dependent decreases in hindgut motility, and responded to proctolin with reversible, dosage‐dependent increases in hindgut motility. When both allatostatin and proctolin were applied to hindgut preparations simultaneously and in equal concentrations, the response varied with the stage of the male. Starvation enhanced hindgut motility and abolished the response to allatostatin, but not to proctolin.

These results indicate the presence of material similar to cockroach allatostatins in male earwigs, and that the levels change with age and physiological stage. Furthermore, such peptides may indeed be regulatory neuropeptides and could modulate hindgut contraction. There was an increase in sensitivity to exogenous allatostatin in the hindgut during development from day 0 to day 8 in feeding males, but a loss in sensitivity in response to starvation; sensitivity to exogenous proctolin also increased with age, but such responsiveness was not diminished by starvation.
Effect of host stimuli on ovariole development in the walnut fly, Rhagoletis juglandis (Diptera, Tephritidae)
Authors: Lachmann Anja D. , Papaj Daniel R.
Published: September 2010

Although examples of non‐nutritive effects of host resources on ovarian development in insects are known, precise descriptions of effects on ovariole formation and development are rare. In this study, we provide a description with respect to the enhancement of egg production, or egg load, by surrogate fruit stimuli (yellow plastic spheres) in the walnut fly, Rhagoletis juglandis Cresson. A system for staging developing ovarioles was established, and cohorts of females held from emergence with or without surrogate fruit were sampled over time with respect to number of ovarioles as well as number and stage of follicles within ovarioles. As found previously, the presence of surrogate fruit strongly enhanced production of eggs in the first maturation cycle. The effect was probably not due to oosorption in the ovaries of females held without surrogates; in fact, oosorption was never observed in ovaries of females in either treatment. The effect was due in part to an increase in ovariole number in females held with surrogates; in each of two trials, mean ovariole number was slightly but significantly greater for females held with vs. without spheres. However, the main effect was also due in part to an earlier onset and increased rate of vitellogenesis in the first and second follicles of females held with spheres.
Social influence of larvae on ovarian maturation in primary and secondary reproductives of the dampwood termite Zootermopsis angusticollis
Authors: Brent C. S. , Traniello J. F. A.
Published: September 2010

We tested the effect of larvae on the reproductive maturation and fecundity of female primary and secondary reproductives of the termite Zootermopsis angusticollis Hagen (Isoptera; Termopsidae) by varying the number of third‐ to fourth‐instar larvae nesting with heterosexually paired reproductives. Primary females had higher fecundities and oviposited sooner when nesting with larvae than females lacking larvae, but gained less body mass and had fewer functional ovarioles per ovary. Secondary reproductives nesting with larvae also had higher fecundities and oviposited sooner, but unlike primaries, they gained more body mass and had more functional ovarioles when larvae were present. The specific response of both primary and secondary females varied according to the number of larvae present. These results suggest that larvae can enhance the fecundity of primary and secondary females. Larvae may increase the energetic reserves of reproductives by performing colony labour, reducing pathogen load and providing trophallactic secretions. Trophallaxis with larvae may significantly enhance endogenous nitrogen, which is a limiting nutrient for termites.

Primary females, which normally need to produce a first brood quickly to initiate a new colony, may expend limited nutritional resources on oogenesis rather than producing additional ovarioles. Primaries may also store fewer energetic reserves for long‐term brood care, and therefore gained less mass when larvae were present to attend to non‐reproductive tasks. Secondary females may exhibit a greater positive response to larvae than primaries because they begin reproductive life with fewer stored resources and thus their development and fecundity are more dependent on assistance from larvae. Both primary and secondary reproductives may become more dependent on the contributions of larvae as their rate of egg production increases with subsequent bouts of oviposition.
Effects of temperature, sorbitol, alanine and diapause hormone on the embryonic development in Bombyx mori: in vitro tests of old hypotheses
Authors: Iwata Ken‐Ichi , Fujiwara Yoshihiro , Takeda Makio
Published: September 2010

Abstract.  An in vitro culture method is described in which embryonic development in Bombyx mori is traced at various temperatures and treatments. The results show that the induction, intensification and termination of diapause are distinct processes. Prediapause embryos, explanted from 40‐h‐old diapause‐destined eggs and cultured in Grace's medium, continue to develop to the appendage‐formation stage without arrest, which indicates that the isolated embryos have not entered diapause, whereas the development of embryos from diapausing eggs (15 days after being laid) is significantly slower. The rate of development of embryos dissected from diapause eggs increases during chilling (5 °C) and incubation (at 25 °C) gradually during chilling and dramatically at 25 °C. The in vitro experiments also reveal that sorbitol directly inhibits the development of embryos explanted from diapausing eggs but has no affect on the development of embryos from prediapause eggs. Neither alanine nor diapause hormone prevent isolated embryos from developing.
Adaptations to environmental stress in altitudinal populations of two Drosophila species
Authors: Parkash Ravi , Tyagi Pankaj K , Sharma Indu , Rajpurohit S.
Published: September 2010

Abstract.  Opposite clinal variation for desiccation and starvation tolerance are observed in four altitudinal populations (219–2202 m), each of two sympatric and cold adapted species: Drosophila takahashii and Drosophila nepalensis from northern India. The high‐altitude populations are more tolerant to desiccation than those from lower altitudes, whereas the reverse trend occurs for starvation tolerance. The magnitude of tolerances are significantly high in D. nepalensis, which is better adapted to cold conditions. During winter months (November to February), there are significant decreases in Tmax, Tmin and relative humidity along the altitudinal transect. Higher desiccation resistance can develop under cold conditions over short‐range, altitudinally varying, geographical areas (250 km) compared with our previously reported long‐range (>2000 km), latitudinal variations under tropical climatic conditions. However, significant starvation tolerances are favoured by small body size, higher dispersal rate and higher ambient temperature of the site of origin of populations. Significant correlations of two climatic factors (the mean monthly coefficients of variation of temperature and relative humidity) with these two physiological traits can best explain the observed altitudinal clinal variations under natural conditions.