bluuebunny/crossref_metadata_2025_split huggingface dataset:
Migration of specialist insect predators to exploit patchily distributed spider mites
Authors: Shimoda T. , Takabayashi J. 
Published: April 2006

AbstractIt is believed that specialist predators of spider mites often migrate by flight or aerial transport to exploit patchily distributed prey. The migration is an important factor in determining the seasonal occurrence of the predators in a field. Several species of specialist insect predators, such as Oligota kashmirica benefica (Coleoptera: Staphylinidae) and Scolothrips takahashii (Thysanoptera: Thripidae), migrate between orchard trees and plants near the trees (e.g., groundcover, weeds, or windbreaks) to exploit abundant spider mites. This migration is at least partly triggered by prey scarcity in the original local habitats. Although these predators are tiny insects, they have flight abilities. For example, adult O. kashmirica benefica (body length, ∼1 mm) could move at least 5–16 m in one flight. Presumably, migration of the insect predators between prey‐infested plants occurs mainly by flights. Predatory mites, such as Amblyseius fallacis and Amblyseius womersleyi (Acari: Phytoseiidae), migrated to spider mite‐infested plants outside an orchard by aerial transport when they suffered from prey scarcity in the orchard. S. takahashii can use plant volatiles from lima bean plants induced by the spider mite Tetranychus urticae as cues for prey location during migration in Satsuma mandarin groves. However, it remains unknown how far from the trap boxes S. takahashii could respond to herbivore‐induced plant volatiles in the groves.
Infochemically mediated tritrophic interaction webs on cabbage plants
Authors: Shiojiri K. , Takabayashi J. , Yano S. , Takafuji A. 
Published: April 2006

AbstractIn response to damage by herbivores, plants are known to emit infochemicals that enhance the effectiveness of insect parasitoids. Studies on plant–parasitoid interactions mediated by such infochemicals have focused on the tritrophic systems in which plants are infested by a single herbivore species. In natural ecosystems, however, plants are often simultaneously infested by several herbivorous species. The present study focuses on two herbivorous species that simultaneously attack crucifer plants and their respective parasitic wasps. We first show the specific responses of the two specialist parasitic wasps [Cotesia plutellae and C. glomerata (Hymenoptera: Braconidae)] to infochemicals originating from cabbage plants (Brassica oleracea cv. Sikidori) infested by each of their respective host larvae [Plutella xylostella (Lepidoptera: Yponomeutidae) and Pieris rapae (Lepidoptera: Pieridae)]. We then coupled the two tritrophic systems on the same cabbage plants. These experiments demonstrated the presence of indirect interactions between the two species of herbivores. Overall, the results indicate the presence of infochemically mediated tritrophic interaction webs on a single plant.
Indirect interactions mediated by leaf shelters in animal–plant communities
Authors: Fukui A. 
Published: April 2006

AbstractLeaf shelters indirectly mediate interactions in animal–plant communities by providing the occupants with several kinds of benefits, as physical ecosystem engineering. The occupants benefit from favorable microhabitat, reduction in antiherbivore defense, and protection from natural enemies. The primary shelter maker has to spend energy and time and producing silk, but shelter users have great advantages without incurring costs. Shelter users consist of a wide range of arthropod taxa and can be divided into two groups: coexisting organisms that live with a primary shelter maker in the same shelter, and secondary users, which inhabit a leaf shelter after it is utilized by a shelter maker. Leaf shelters mediate interactions between (1) primary shelter makers and coexisting organisms or (2) primary shelter makers and secondary users, (3) secondary users, (4) shelter users and their natural enemies, and (5) primary shelter makers, secondary users, and their host plants. Most interactions between primary shelter makers and coexisting organisms constitute a direct trophic linkage rather than indirect ones. There are actually unidirectional beneficial effects from a primary shelter maker to secondary shelter users, whereas leaf shelters mediate competition and predation among shelter users. By providing a leaf shelter, a shelter maker leads to increased diversity of interactions. Leaf shelters modify the distribution of organisms on the host plant and influence herbivory on the host plant. In tritrophic interactions, leaf shelters act as cues for natural enemies that search for a shelter user as prey. Furthermore, by enhancing habitat heterogeneity, leaf shelters affect the abundance and species richness of arthropods on host plants.
A review of the ecological parameters and implications of subsociality in Parastrachia japonensis (Hemiptera: Cydnidae), a semelparous species that specializes on a poor resource
Authors: Filippi L. , Hironaka M. , Nomakuchi S. 
Published: April 2006

AbstractSubsocial behavior or postovipositional parental care in insects has evolved in response to a variety of environmental stresses and ranges from briefly guarding eggs after oviposition to elaborate nidification and provisioning behaviors. Investment in parental care bears various costs, and should not continue beyond the point at which the costs to future reproductive success exceed the benefits to current reproductive effort. Progressive provisioning is a rare form of subsociality in insects. Females of the subsocial shield bug Parastrachia japonensis progressively provision their nymph‐containing nests with drupes of the single resource, Schoepfia jasminodora, and this provisioning drastically enhances offspring survival. A female rears only one brood throughout her lifetime and continues provisioning the brood until about the third larval stadium, when the female dies. Thus, the female's entire reproductive effort is expressed in the success of that one brood, which suggests a reproductive strategy with enormous costs and risks. Why has such an extreme life history evolved in this species? Here, to answer that question and to contribute to our understanding of the evolutionary implications of subsocial behavior, in particular, progressive provisioning, we review what we have discovered about the ecological parameters of subsociality in this species during a long‐term field study. We also discuss these parameters in P. japonensis in reference to other subsocial insects and related species and conclude with a suggestion that semelparity and progressive provisioning in this species are extreme adaptations to evolving complete dependency on an unreliable resource.
Do competing honey bees matter? Dynamics and abundance of native bees before and after honey bee invasion
Authors: Roubik D. W. , Wolda H. 
Published: April 2006

AbstractTo provide replicate samples of local bee populations in a nature preserve, light traps operated continuously on Barro Colorado Island (BCI), Panama, collected bees for 17 years, including 10 years following invasion by African Apis mellifera. Honey bees appeared in light traps as the first swarms colonized the Panama Canal area. Their numbers followed seasonal trends shown in inde‐pendent studies, thus indicating bee abundance and activity in a large area. No measurable population‐level impact of competition between this invading honey bee and native bees, despite many demonstrations of resource competition at flower patch and colony levels, changed annual abundances of all 15 native bee species. Native bee abundance did not decrease, nor did native bees show substantial reciprocal yearly change with honey bee abundance. One strong negative correlation of bee catches with an extremely rainy year was found. However, multiple regression using rainfall and honey bee abundance as the independent variables showed that neither was responsible for bee population change over 17 years. Nearly half the native species declined during a year that displayed peak honey bee number. That competition from honey bees on an island the size of BCI was necessarily reduced below impact levels expected on the mainland is discussed using a model of resource and consumer density, foraging range, and island size.
Drought and the consequences of El Niño in Borneo: a case study of figs
Authors: Harrison R. D. 
Published: April 2006

AbstractBorneo has a perhumid climate but occasional severe droughts have an important impact. Droughts may affect the composition and size structure of plant communities through differential mortality or, via their impact on the availability of plant resources, affect plant–animal interactions. From January to April 1998, northern Borneo suffered a very severe drought linked to the El Niño Southern Oscillation event of 1997–1998. In this article, the impacts of this drought on the rain forest at Lambir Hills National Park, Sarawak, are considered with special reference to a keystone plant group, the figs. Small fires entered the edge of the forest from the roadside, killing saplings, climbers, and understory trees. Community‐wide mortality for adult trees was 0–7 times higher than in nondrought years, with larger trees showing a greater proportional increase. In figs, mortality was significantly higher in pioneers, but hemiepiphytes and roadside species were unaffected. Phenology was substantially affected. Leaf and flower/fruit production decreased or ceased during the drought and increased suddenly following renewed rain. Pollinators of dioecious figs became locally extinct during the drought, and other plant–animal interactions may also have been disrupted. The frequency and severity of droughts has increased substantially in the past three decades, and climate models suggest this may be the result of global warming. The impacts of the 1998 drought at Lambir Hills National Park suggest that, should this trend continue, a substantial alteration of habitats and overall loss of biodiversity can be expected in Borneo.
Competition for a limited space in kleptoparasitic Argyrodes spiders revealed by field experiments
Authors: Miyashita T. 
Published: April 2006

AbstractMost kleptoparasitic Argyrodes spiders rely exclusively on host spider webs for obtaining their food. Because their densities occasionally reach high levels within a restricted area, competitive interactions may be important for determining the density of these unique spiders. Here I used two Argyrodes species commonly found on webs of the large orb‐web spider Nephila clavata to clarify whether inter‐ and intraspecific competition influences abundance and within‐web distribution by using observational data and field experiment. Removing Argyrodes flavescens from the host webs induced a remarkably high immigration of that species while density on control webs remained almost at the same level, which is evidence for strong intraspecific competition. Larger individuals of A. flavescens were located more frequently at the capture area of the host webs where it is easy to access prey ignored by the host spider, and spiders immigrating into webs from which that species had been removed were smaller in body size, suggesting interference competition for space among conspecific kleptoparasites. Argyrodes bonadea increased in number on webs from which A. flavescens had been removed, and the increase was correlated with the number of A. flavescens removed. This finding is evidence for interspecific competition that is rarely reported in spiders. A multiple regression model including numbers of a conspecific parasite as well as web and body sizes of the host spider could not detect competitive interactions between species, suggesting the importance of experimental approaches.
Recovery plan for an exploited species, southern bluefin tuna
Authors: Mori M. , Katsukawa T. , Matsuda H. 
Published: April 2006

AbstractSouthern bluefin tuna (SBT) were heavily depleted in the mid‐1980s, and the fishing quota has been restricted since 1985. As a result of this restriction and protection of immature individuals, spawning stock biomass (SSB) recently has shown a slight increase. The Commission for the Conservation of Southern Bluefin Tuna (CCSBT) has the target of recovering SSB to the 1980 level by 2020. We investigated whether SBT populations will recover and reach the target level set by CCSBT. Our projection shows that the SSB of the SBT will temporarily decrease again after 1999. This temporary decrease of SSB does not always mean failure of the recovery plan, because the SSB trend is highly vulnerable to age‐composition dynamics. The SBT is an example of this. The number of mature SBT was small during the 1980s because of overfishing. Thus, the number of eggs that were spawned by these mature SBT was small in these years, and when these small numbers of immature fish become mature, the SSB will decrease again. We call this effect the inverse baby‐boom effect. The inverse baby‐boom effect may be common for managed bioresources that have once been overexploited. We also examine the use of spawning potential (SP) and SSB as an index of stock recovery.
Blood Supply and Parathyroid Hormone Secretion in Pathological Parathyroid Glands
Authors: Ander Stefan , Johansson Kenth , Smeds Stafan 
Published: April 2006

AbstractThe blood supply of pathologic parathyroid glands and the relation between parathyroid hormone secretion and parathyroid blood perfusion was studied during surgery for hyperparathyroidism. Blood flow in 39 single adenomas and 20 glands classified as primary or secondary hyperplasia were studied intraoperatively with laser Doppler flowmetry. The ipsilateral inferior thyroid artery was occluded during continuous flowmetry recording, which resulted in a 40% reduction of parathyroid blood flow in both groups. In 12 patients with single adenomas, intact parathormone (iPTH) was measured intraoperatively before and during occlusion of the ipsilateral inferior thyroid artery and after extirpation of the adenoma. During occlusion the iPTH levels were mainly unchanged despite blood flow reduction of up to 80%. After removal of the adenoma the iPTH normalized within 15 minutes. In a control group of eight single adenomas, iPTH was measured similarly without vascular occlusion, demonstrating comparable iPTH levels. This study demonstrates similar routes of vascularization for single adenomas and hyperplastic glands, as was earlier seen for normal parathyroid glands. The increased parathyroid hormone secretion from single adenomas appears to remain mainly unchanged during significant blood flow reduction.
Clinicopathologic Study for the Assessment of Resection for Ampullary Carcinoma
Authors: Böttger Thomas C. , Boddin Jörg , Heintz Achim , Junginger T. 
Published: April 2006

AbstractIn a prospective observational study including 34 patients with carcinoma of the ampulla of Vater, postoperative morbidity, mortality, and long‐term survival were analyzed to determine the surgical procedure of choice. Surgically related postoperative complications were observed in 35.4% of patients after pancreatic resection. No patient died within the first 30 days postoperatively, and in‐hospital mortality was 3%. Lymph node metastases were associated only with moderate or undifferentiated tumors larger than 0.6 cm in diameter that infiltrated beyond the ampulla of Vater. The median follow‐up time was 4.3 years. The 5‐year survival rate for the 31 patients undergoing radical resection was 62.7%. Multivariate analysis (including the covariates depth of tumor infiltration, lymph node metastases, and the ratio of metastatic to dissected lymph nodes) demonstrated that only this ratio exerted an independent influence on the prognosis (p= 0.001). The present series demonstrates that radical resection of ampullary cancer is the procedure of choice even in elderly patients. The most important factor influencing the survival rate is the extent of the lymph node dissection. The histopathologic investigation of our pancreatoduodenectomy specimens demonstrates clearly that local excision of ampullary cancer may be indicated only in high risk patients with a pT1, well differentiated tumor smaller than 0.6 cm in diameter.
High Preoperative Serum Alanine Transferase Levels: Effect on the Risk of Liver Resection in Child Grade A Cirrhotic Patients
Authors: Noun Roger , Jagot Pascal , Farges Olivier , Sauvanet Alain , Belghiti Jacques 
Published: April 2006

AbstractDespite careful selection of cirrhotic patients with hepatocellular carcinoma (HCC), liver resection remains associated with a greater risk than in patients without underlying liver disease. In this study we assessed by multivariate analysis parameters associated with in‐hospital mortality and morbidity in a selected group of 108 Childs‐Pugh A cirrhotic patients undergoing liver resection of HCC. The overall incidences of in‐hospital deaths and postoperative complications were 8.3% and 48.1%, respectively. By univariate analysis, the preoperative serum alanine transferase (ALT) level (p= 0.001) and intraoperative transfusions (p= 0.01) were significantly associated with in‐hospital death; however, only the serum ALT concentration was an independent risk factor. In‐hospital mortality rates in patients whose serum ALT was below 2N (twofold the upper limit of the normal value), between 2N and 4N, and more than 4N were 3.9%, 13.0%, and 37.5%, respectively. An ALT level greater than 2N was predominantly observed in patients with a hepatitis C virus infection and significantly associated with histologic features of superimposed active hepatitis. Patients with an ALT level greater than 2N experienced an increased incidence of postoperative ascites (58% versus 32%,p= 0.01), kidney failure (16% versus 0%,p= 0.0003), and upper gastrointestinal bleeding
(6.4% versus 0%, p= 0.02). These results indicate that the preoperative ALT level is a reliable predictor of in‐hospital mortality and morbidity following liver resection in Child‐Pugh A cirrhotic patients. Cirrhotic patients with ALT > 2N should undergo only a limited resection; if a larger resection is required, those patients should be considered for nonsurgical therapy or liver transplantation.
Changes in Body Composition after Gastrectomy: Results of a Controlled, Prospective Clinical Trial
Authors: Liedman B. , Andersson H. , Bosaeus I. , Hugosson I. , Lundell L. 
Published: April 2006

AbstractTo elucidate mechanisms involved in weight development after gastrectomy we have prospectively determined changes in body composition during the first year after similar operations. A total of 75 patients were enrolled who had a “curative operation” for gastric carcinoma; 42 were randomized to have a total gastrectomy, 23 total gastrectomy with a gastric substitute, and 10 subtotal gastrectomy. All reconstructions were done with a Roux‐en‐Y loop of the jejunum. Body composition was assessed preoperatively and at 6 and 12 months after gastrectomy by determining total body potassium and total body water. From these estimates, body cell mass, extracellular water, fat‐free extracellular solids, and body fat were calculated with knowledge of the actual body weight and length. Triceps skinfold, arm muscle circumference, and grip strength were also measured. Weight loss (10% of preoperative weight) occurred early after the operations, after which body weight stabilized. Body cell mass remained essentially unchanged over the entire study period in contrast to body fat, which decreased by 40% during the first 6 months after gastrectomy. In accordance with the selective loss of body fat, we recorded a significant decrease in triceps skinfold figures and only a minor decrease of arm muscle circumference without obvious deterioration in hand grip strength. Weight loss after gastrectomy seems to be characterized by selective loss of body fat in contrast to other known clinical situations associated with impaired nutritional intake. Our observations form a basis for future clinical research aimed at preventing weight loss after these operations.
Quality of Life after Gastrectomy for Gastric Carcinoma: Controlled Study of Reconstructive Procedures
Authors: Svedlund Jan , Sullivan Marianne , Liedman Bengt , Lundell Lars , Sjödin Ingemar 
Published: April 2006

AbstractThe choice of reconstruction after gastrectomy and the significance of remaining reservoir function is a matter of controversy. To broaden the criteria for choice of treatment, we conducted a prospective randomized clinical trial to determine the impact of various gastrectomy procedures on quality of life. Consecutive patients (n= 64) eligible for curative gastric cancer surgery were randomized to have either a total (n= 31) or subtotal (n= 13)
gastrectomy or a jejunal S‐shaped pouch (n= 20) implanted as a gastric substitute. The quality‐of‐life evaluation was based on a battery of questionnaires covering both general and specific aspects of life. The patients were rated by one of two psychiatrists who were blinded to the patients’ group affiliation. Assessments were made on three occasions: during the week prior to surgery and 3 and 12 months after the surgical intervention. The postoperative complication and mortality rates were similar in all treatment groups, with few serious complications recorded. Irrespective of type of treatment, the patients suffered from alimentary symptoms and functional limitations in everyday life, whereas their mental well‐being improved after surgery. Patients who underwent subtotal gastrectomy had the best outcome, especially with respect to complaints of diarrhea. Patients given a gastric substitute after gastrectomy showed no difference from those who had only a total gastrectomy. We conclude that despite significant unfavorable consequences that follow gastrectomy, patients recover with an improved mental status. A pouch reconstruction after total gastrectomy does not improve quality of life, but a subtotal gastrectomy has advantages that must be considered when the procedure is clinically feasible.
Causes of Death and Recurrence after Surgery for Early Gastric Cancer
Authors: Guadagni Stefano , Catarci Marco , Kinoshitá Taira , Valenti Marco , De Bernardinis Giancarlo , Carboni Manlio 
Published: April 2006

AbstractThe postoperative course of 172 patients with early gastric cancer (EGC) was followed for a median 7 years to evaluate the causes of death, incidence and patterns of recurrence, and characteristic findings in the recurrent cases. The cumulative 10‐year mortality rate (± SE) was 22 ± 3.7%. Seven patients (4.1%) died of operative mortality, 11 (6.4%) died of a recurrence of the gastric cancer, and 13 (7.6%) died of unrelated causes. Unrelated causes of death were metachronous primary cancer (n = 6), cardiovascular disease (n= 2), pneumonia (n= 3), sepsis (n= 1), and car accident (n= 1). Four patients died from gastric stump recurrence, three from liver metastases, two from lymph node metastases, and two from peritoneal dissemination. Using Cox multivariate analysis, histologic type had the most significant effect on recurrence. Although influenced by the tumor nature, the EGC prognosis is relatively good. Based on the results of this study, particularly in Western institutions, histologic examination of resection margins and lymphadenectomy should be improved. Moreover, patients must be carefully followed for late recurrence and metachronous cancer.