bluuebunny/crossref_metadata_2025 huggingface dataset:
Centaurea solstitialis Invasion Success Is Influenced by Nassella pulchra Size
Authors: Reever Morghan Kimberly J. , Rice Kevin J.
Published: August 2005

Replacement of perennial grasses with non‐native annual grasses in California's Central Valley grasslands and foothills has increased deep soil water availability. Yellow starthistle (Centaurea solstitialis), a deep‐rooted invasive thistle, can use this water to invade annual grasslands. Native perennial bunchgrasses, such as Purple needlegrass (Nassella pulchra), also use deep soil water, so there is an overlap in resource use between N. pulchra and C. solstitialis. Restoration of N. pulchra to annual grasslands could result in strong competitive interactions between N. pulchra and C. solstitialis, which may reduce survival, growth, and reproduction of the invader. The strength of this competitive interaction can increase as N. pulchra plants mature, increase in size, and develop more extensive root systems. We studied how the size of N. pulchra affected the success of C. solstitialis invasion over 2 years. We allowed C. solstitialis seed to fall naturally into plots containing N. pulchra plants. For each plot, we measured the number of C. solstitialis seedlings and mature plants, as well as C. solstitialis biomass and seedhead production. In both years of the study, C. solstitialis number, biomass, and seedhead production declined significantly as N. pulchra size increased. However, even C. solstitialis grown with the largest N. pulchra plants produced some seed, especially during the higher rainfall year. We conclude that restoration plantings with larger, established N. pulchra plants will be more resistant to invasion by C. solstitialis than young N. pulchra plantings, but site management must continue as long as a C. solstitialis seed source is present.
Long‐Term Effects of Biosolids on Revegetation of Disturbed Sagebrush Steppe in Northwestern Colorado
Authors: Paschke Mark W. , Topper Karl , Brobst Robert B. , Redente Edward F.
Published: August 2005

A study was conducted to evaluate the long‐term effects of biosolids amendment on restoration of disturbed sagebrush steppe habitat in northwestern Colorado. Twenty‐four years after biosolids amendment, soil fertility and plant community development were studied in replicated plots receiving various biosolids amendments on two different substrates. The two substrates used were a subsoil, determined to have low initial fertility, and a topsoil over retorted shale substrate, determined to have relatively high initial fertility. Results suggest that biosolids amendments have long‐lasting effects on soil fertility and plant community composition, but these effects vary between the two substrates that were utilized. Within the plots established on subsoil, the long‐term effect of biosolids was a reduction in plant species diversity and dominance by perennial grasses. On the topsoil substrate, there was a decrease in perennial grasses and an increase in shrub dominance with increasing biosolids. Results demonstrate the importance of considering initial soil conditions, seed mixture, and biosolids application rate when using biosolids for restoration of disturbed sagebrush steppe habitat. The long‐term effects of the biosolids treatments at this site demonstrate the need to consider restoration treatment effects over longer and more ecologically meaningful time frames.
A Climate‐Based Approach to the Restoration of Fire‐Dependent Ecosystems
Authors: Beckage Brian , Platt William J. , Panko Bob
Published: August 2005

Recurrent fires are integral to the function of many ecosystems worldwide. The management of fire‐frequented ecosystems requires the application of fire at the appropriate frequency and seasonality, but establishing the natural fire regime for an ecosystem can be problematic. Historical records of fires are often not available, and surrogates for past fires may not exist. We suggest that the relationship between climate and fire can provide an alternative means for inferring past fire regimes in some ecosystems.
Fire and Litter Effects on Seedling Establishment in Western Oregon Upland Prairies
Authors: Maret Mary P. , Wilson Mark V.
Published: August 2005

Prescribed burning is an important tool for managing and restoring prairies and other ecosystems. One effect of fire is plant litter removal, which can influence seedling establishment. Four experimental treatments (burned, clipped and raked to remove litter, burned with litter reapplied, and unmanipulated) were applied to 2 × 2.5–m plots in three western Oregon, United States, upland prairies to determine how burning affects seedling establishment. Seeds of common exotic and native prairie species were sowed into the experimental plots after treatments. Seedlings were censused the following spring. The experiment was repeated on each of the three sites, representing three common types of prairie vegetation: an Annual Exotic Grass site, a Perennial Exotic Grass site, and a Native Bunchgrass site. In both the Annual Exotic Grass and the Perennial Exotic Grass sites, burning significantly improved native, but not exotic, seedling establishment over those on unburned plots. Litter removal was a significant component of this burn effect, particularly on the Perennial Exotic Grass site. In these winter‐moist systems, the net effect of litter is to inhibit seedling establishment. Burning treatments on the Native Bunchgrass site significantly increased seedling establishment only of short‐lived exotic species. These results suggest that in prairie ecosystems similar to the Annual and Perennial Exotic Grass sites, prescribed burning followed by sowing native seeds can be an effective restoration technique. Burning alone or sowing alone would be counter‐productive, in the first case because increased establishment would come from exotic species and in the second case because establishment rates are low in unburned plots.
Restoration Success: How Is It Being Measured?
Authors: Ruiz‐Jaen Maria C. , Mitchell Aide T.
Published: August 2005

The criteria of restoration success should be clearly established to evaluate restoration projects. Recently, the Society of Ecological Restoration International (SER) has produced a Primer that includes ecosystem attributes that should be considered when evaluating restoration success. To determine how restoration success has been evaluated in restoration projects, we reviewed articles published in Restoration Ecology (Vols. 1[1]–11[4]). Specifically, we addressed the following questions: (1) what measures of ecosystem attributes are assessed and (2) how are these measures used to determine restoration success. No study has measured all the SER Primer attributes, but most studies did include at least one measure in each of three general categories of the ecosystem attributes: diversity, vegetation structure, and ecological processes. Most of the reviewed studies are using multiple measures to evaluate restoration success, but we would encourage future projects to include: (1) at least two variables within each of the three ecosystem attributes that clearly related to ecosystem functioning and (2) at least two reference sites to capture the variation that exist in ecosystems.
Brush Allodynia in Hospitalized Headache Patients
Authors: Young William B. , Richardson Elizabeth S. , Shukla Pragati
Published: August 2005

Objective.—To describe the incidence and time course of dynamic mechanical allodynia (brush allodynia, BA) in an inpatient headache population.

Background.—Four types of cutaneous allodynia (heat, cold, static mechanical [pressure], and dynamic mechanical [brush] allodynia) can be studied in headache patients. In episodic migraineurs, the development of cutaneous allodynia heralds a change in treatment response. However, little is known about the functional significance of BA, and little is known about the frequency of any type of cutaneous allodynia among patients with chronic or more severe headache disorders.

Methods.—The protocol was approved by the institutional review board of our university hospital. A total of 78 subjects were tested for allodynia on days 1, 3, and 5 of an inpatient hospital stay using a 4 × 4 folded gauze pad stroked 10 times at three bilateral sites (forehead, jaw, and forearm). Subjects were queried about the signs and symptoms of their headaches. Headache intensity was graded with a verbal 11‐point scale and the intensity of allodynia was graded using a 10 cm visual analog scale.

Results.—A total of 61 patients had transformed migraine (TM). BA was present at some point during the hospitalization in 32 subjects (41%). Neither age nor duration of daily headache correlated with headache severity. Headache intensity, a history of sensory symptoms or weakness, and subjective blurred vision accompanying the headache correlated with the presence of BA (P≤ .05). Unilateral headaches were more likely to be associated with BA (P= .01), independent of headache severity. When headache was unilateral, BA was greatest ipsilateral to the headache. BA did not influence outcome as measured by length of stay or the likelihood of being discharged headache‐free. The rate of decline of headache intensity and allodynia score were similar.

Conclusion.—BA is common in hospitalized headache patients. Subjects with more severe unilateral headaches were more likely to have BA. The presence of BA did not predict treatment failure in an inpatient setting.
Burden of Illness and Satisfaction With Care Among Patients With Headache Seen in a Primary Care Setting
Authors: Harpole Linda H. , Samsa Gregory P. , Matchar David B. , Silberstein Stephen D. , Blumenfeld Andrew , Jurgelski Annette E.
Published: August 2005

Objective.—To assess the current level of headache burden and the headache management needs at three diverse clinical sites.

Background.—Headache is a common disabling disorder that is costly for the patient and a management challenge for physicians. The determination of whether and how to intervene to improve headache management depends on both the burden of disease and the characteristics of patients that would likely be targeted.

Methods.—Patients from three healthcare organizations were identified by administrative records as having either migraine or tension‐type headache and then mailed a survey that addressed demographics, headache type, headache‐related disability, depression and anxiety, satisfaction with care, general health, worry about headache, problems with headache management, and healthcare utilization. Comparisons were made across sites and between patients with more and less severe headache‐related impairments.

Results.—Of the 789 patients contacted, 385 (50%) returned a survey. While the socio‐demographic characteristics of the patients were diverse, headache‐related characteristics were similar. These patients have significant problems with headache management, disability, pain, worry, and dissatisfaction with care. Patients who described higher headache‐related impairment experienced significantly greater problems in these areas, perceived themselves to be in worse general health, and had significantly greater use of medical services than those with lower headache severity.

Conclusions.—Despite various elements of heterogeneity, we observed across the sites a consistent need for improvement in headache management. Future efforts should be directed at developing and evaluating methods for effectively improving headache management.
Treatment of Cluster Headache Attacks With Less Than 6 mg Subcutaneous Sumatriptan
Authors: Gregor Nora , Schlesiger Christian , Akova‐Öztürk Esra , Kraemer Christoffer , Husstedt Ingo‐Wilhelm , Evers Stefan
Published: August 2005

Background.—Subcutaneous (SQ) sumatriptan 6 mg is effective in the treatment of acute cluster headache attacks. However, patients sometimes benefit from a dose less than 6 mg.

Objective.—Therefore, we designed a prospective open study to evaluate how many patients benefit from a dose less than 6 mg SQ sumatriptan.

Methods.—We enrolled 81 consecutive patients with cluster headache and recorded their use of SQ sumatriptan and oxygen. Patients regularly using SQ sumatriptan 6 mg were advised to treat attacks with doses less than 6 mg and with oxygen. Efficacy and side effects of the different treatment options (6 mg, 3 mg, 2 mg, and oxygen) were evaluated.

Results.—As a result, 74% of the patients using SQ sumatriptan 3 mg showed efficacy and 89% reported efficacy after 2 mg. Seventy‐nine percent reported side effects after the use of SQ sumatriptan 6 mg (29% severe side effects). After the use of 2 mg SQ sumatriptan, only 50% of the patients reported side effects, none of these were classified as severe. Patients' preference was 41% for 6 mg sumatriptan, 28% for doses less than 6 mg, and 31% for oxygen.

Conclusions.—We conclude that sumatriptan in doses less than 6 mg can be effective in the acute treatment of cluster headache attacks. We suggest that patients should have experience in their individual efficacy of sumatriptan doses less than 6 mg.
Moral Hazard in Reinsurance Markets
Authors: Doherty Neil , Smetters Kent
Published: August 2005

Abstract

This article attempts to identify moral hazard in the traditional reinsurance market. We build a multiperiod principal–agent model of the reinsurance transaction from which we derive predictions on premium design, monitoring, loss control, and insurer risk retention. We then use panel data on U.S. property liability reinsurance to test the model. The empirical results are consistent with the model's predictions. In particular, we find evidence for the use of loss‐sensitive premiums when the insurer and reinsurer are not affiliates (i.e., not part of the same financial group), but little or no use of monitoring. In contrast, we find evidence for the extensive use of monitoring when the insurer and reinsurer are affiliates, where monitoring costs are lower.
Financial Intermediary Versus Production Approach to Efficiency of Marketing Distribution Systems and Organizational Structure of Insurance Companies
Authors: Brockett Patrick L. , Cooper William W. , Golden Linda L. , Rousseau John J. , Wang Yuying
Published: August 2005

Abstract

An examination of the efficiency of the marketing distribution channel and organizational structure for insurance companies is presented from a framework that views the insurer as a financial intermediary rather than as a “production entity” which produces “value added” through loss payments. Within this financial intermediary approach, solvency can be a primary concern for regulators of insurance companies, claims‐paying ability can be a primary concern for policyholders, and return on investment can be a primary concern for investors. These three variables (solvency, financial return, and claims‐paying ability) are considered as outputs of the insurance firm. The financial intermediary approach acknowledges that interests potentially conflict, and the strategic decision makers for the firm must balance one concern versus another when managing the insurance company. Accordingly, we investigate the efficiency of insurance companies using data envelopment analysis (DEA) having as insurer output an appropriately selected (for the firm under investigation) combination of solvency, claims‐paying ability, and return on investment as outputs. These efficiency evaluations are further examined to study stock versus mutual form of organizational structure and agency versus direct marketing arrangements, which are examined separately and in combination. Comparisons with the “value‐added” or “production” approach to insurer efficiency are presented. A new DEA approach and interpretation is also presented.
Subsidization and Choice in the Group Health Insurance Market
Authors: Ma Yu‐Luen , Browne Mark
Published: August 2005

Abstract

This study investigates the effect of group health insurance plan choice on insurance unit price. The empirical findings suggest that the unit price of insurance, as measured by the ratio of the premium to expected indemnity benefits, is lower in group plans that offer employees a choice of different insurance options and require a premium contribution than it is in plans lacking at least one of these two features. The analyses suggest that lower unit prices are related to an increase in indemnity benefits and that the reduction in the unit price is greater for lower risks. The findings indicate that although subsidization of high risks by low risks occurs with group health insurance, the degree of subsidization is less when employees are offered a choice of health insurance plans.
Estimating the Cost of Equity Capital for Property‐Liability Insurers
Authors: Cummins J. David , Phillips Richard D.
Published: August 2005

Abstract

This article presents new evidence on the cost of equity capital by line of insurance for the property‐liability insurance industry. To do so we obtain firm beta estimates and then use the full‐information industry beta (FIB) methodology to decompose the cost of capital by line. We obtain full‐information beta estimates using the standard one‐factor capital asset pricing model and extend the FIB methodology to incorporate the Fama–French three‐factor cost of capital model. The analysis suggests the cost of capital for insurers using the Fama–French model is significantly higher than the estimates based upon the CAPM. In addition, we find evidence of significant differences in the cost of equity capital across lines.
The Simple Analytics of a Pooled Annuity Fund
Authors: Piggott John , Valdez Emiliano A. , Detzel Bettina
Published: August 2005

Abstract

This article provides a formal analysis of payout adjustments from a longevity risk‐pooling fund, an arrangement we refer to as group self‐annuitization (GSA). The distinguishing risk diffusion characteristic of GSAs in the family of longevity insurance instruments is that the annuitants bear their systematic risk, but the pool shares idiosyncratic risk. This obviates the need for an insurance company, although such instruments could be sold through a corporate insurer. We begin by deriving the payout adjustment for a single entry group with a single annuity factor and constant expectations. We then show that under weak requirements a unique solution to payout paths exists when multiple cohorts combine into a single pool. This relies on the harmonic mean of the ratio of realized to expected survivorship rates across cohorts. The case of evolving expectations is also analyzed. In all cases, we demonstrate that the periodic‐benefit payment in a pooled annuity fund is determined based on the previous payment adjusted for any deviations in mortality and interest from expectations. GSA may have considerable appeal in countries which have adopted national defined contribution schemes and/or in which the life insurance industry is noncompetitive or poorly developed.
Trends and Directions in the Development of a Strategic Management Theory of the Family Firm
Authors: Chrisman James J. , Chua Jess H. , Sharma Pramodita
Published: August 2005

This article provides a review of important trends in the strategic management approach to studying family firms: convergence in definitions, accumulating evidence that family involvement may affect performance, and the emergence of agency theory and the resource–based view of the firm as the leading theoretical perspectives. We conclude by discussing directions for future research and other promising approaches to inform the inquiry concerning family business.
Determinants of Board Participation in the Strategic Decisions of Small Corporations
Authors: Fiegener Mark K.
Published: August 2005

Agency, strategic choice, and cognitive perspectives are used to examine the conditions under which chief executive officers (CEOs) of small private corporations involve the board of directors in strategic decisions. Logistic regression results (2,382 respondents to a cross–industry mail survey) indicate that board strategic participation is not the dominant practice in these firms but that boards are more likely to participate in strategic decisions when the firm is larger, the board has a critical mass of outside directors, the strategic issue under consideration involves an organizational transition or potential downturn, or CEO power (ownership) is low.
Does mother really know best? Oviposition preference reduces reproductive performance in the generalist parasitoid Aphidius ervi
Authors: Henry Lee M. , Gillespie David R. , Roitberg Bernard D.
Published: August 2005

The reproductive success of female parasitoids is dependent on their ability to accurately assess the suitability of a host for larval development. For generalist parasitoids, which utilize a broad range of species and instars as hosts, a set of assessment criteria determines whether a host is accepted or rejected. The suitability of a host, however, can only be imperfectly assessed by the female parasitoid, which can result in the selection of lesser quality hosts for oviposition. In this study we explored the disparity between host quality and host preference using the generalist koinobiotic parasitoid Aphidius ervi Haliday (Hymenoptera: Aphidiidae) and the host Aulacorthum solani (Harris) (Homoptera: Aphididae), the foxglove aphid. The second instar hosts produced the highest level of reproductive success, while third and fourth instars resulted in a substantially reduced reproductive performance. When given a choice of host instars, parasitoids preferred the older hosts for oviposition disregarding their reduced suitability for larval development. Results are discussed in context of mechanisms involved in A. ervi host selection and biases in the criteria used to assess hosts that may arise when parasitoids transfer host species between generations.
An improved method to determine the biological activity (LC50) of the granulovirus PoGV in its host Phthorimaea operculella
Authors: Sporleder Marc , Kroschel Jürgen , Huber Jürg , Lagnaoui Aziz
Published: August 2005

Granulovirus (PoGV) is a promising candidate to substitute for chemical insecticides in integrated pest management (IPM) of the potato tuber moth, Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae). A procedure to assess pathogenicity (LC50) and its standardization is crucial for research into the use of pathogens as biocontrol agents. In the present study, an egg‐dip bioassay method was developed and its precision tested in a series of six bioassays over a time period of 18 months. Bioassays were carried out at 25 °C incubation temperature. The probit model as a statistical analysis method for the interpretation of concentration responses proved better than the exponential model. LC50 values ranged from 2.3 × 106 to 107 granules ml−1 with a mean of 5 × 106 granules ml−1 and regression slopes varied between 0.73 and 1.05 with a mean of 0.84. LC50 values and slopes displayed no significant differences according to their 95% confidence limits. The rate of harvested infected larvae showed a linear increase with increasing concentration on a log‐log scale. The mean natural mortality was 15% (SE ± 1.8%) and can be considered as a main factor producing variability among bioassays. The advantages of this bioassay method and its application in PoGV research are discussed.
Augmentation of soil detritus affects the spider community and herbivory in a soybean agroecosystem
Authors: Rypstra Ann L. , Marshall Samuel D.
Published: August 2005

If soil detritivores provide a significant prey source for predators in the vegetation, then augmentation of the soil community could affect the grazing food web. Specifically, increases in predator density could enhance any top‐down effects and reduce herbivory. We tested this hypothesis by providing detrital subsidies in the form of composted vegetable matter to 36 m2plots in soybean,Glycine max(L.) Merr. (Fabales: Fabaceae), fields that were managed using either conventional or conservation tillage practices. The foliage‐dwelling spiders, insect predators, and leaf‐chewing insects were censused and the body size of one large spider species,Argiope trifasciata(Forskål) (Araneae: Araneidae), was measured. In addition, the density and size of the plants were assessed and leaf damage was quantified. Any effects of treatments on the palatability of soybean plants to herbivores were determined in two laboratory experiments. Compost increased the density of foliage dwelling spiders and the abdomen size ofA. trifasciata. We uncovered no treatment effects on insect predators, herbivorous insects, or plant characteristics except that compost addition reduced leaf damage. In addition, there was a negative correlation across plots between spider abundance and soybean leaf damage and abdomen width ofA. trifasciataand weed herbivory levels across plots. These results suggest a connection between the soil community and the foliage food web, but the spiders appear to have exerted a top‐down effect without a shift in herbivore abundance. Further study of the specific seasonality of the herbivores and their behavior in the presence of spiders are needed to uncover the underlying mechanism. Nevertheless, these results provide evidence for complex linkage between the soil and grazing food webs that may be important to biological control.
Host‐plant preference of Brachypterolus pulicarius, an inadvertently introduced biological control insect of toadflaxes
Authors: MacKinnon Daniel K. , Hufbauer Ruth A. , Norton Andrew P.
Published: August 2005

Brachypterolus pulicarius (L.) (Coleoptera: Kateridae) is an inadvertently introduced biological control agent that can reduce seed set in two North American invasive species, yellow (Linaria vulgaris P. Mill.) (Scrophulariaceae) and Dalmatian toadflax (Linaria genistifolia (L.) P. Mill. ssp. dalmatica). The beetles are more common on yellow toadflax than on Dalmatian toadflax. To understand their distribution on the two host plants, we investigated whether they prefer one host to the other and whether individuals aggregate toward conspecifics. In field and laboratory experiments where beetles were presented with a choice of both toadflax species, B. pulicarius sampled from both host plants preferred yellow toadflax. However, in the laboratory experiment, beetles collected from Dalmatian toadflax showed a weaker preference for yellow toadflax than beetles collected from yellow toadflax. In the field experiment, all beetle populations sampled showed similar preferences. When given a choice between yellow toadflax plants with and without trapped adult B. pulicarius, beetles preferred plants with conspecifics, suggesting aggregation toward beetle pheromones or host‐plant volatiles induced by beetle activity. These results do not support the current practice of redistributing North American B. pulicarius onto Dalmatian toadflax because of their preference for yellow toadflax.
Grasshoppers efficiently process C4 grass leaf tissues: implications for patterns of host‐plant utilization
Authors: Barbehenn Raymond V.
Published: August 2005

Leaf‐chewing insects are commonly believed to be unable to crush the nutrient‐rich bundle sheath cells (BSC) of C4 grasses. This physical constraint on digestion is thought to reduce the nutritional quality of these grasses substantially. However, recent evidence suggests that BSC are digested by grasshoppers. To directly assess the ability of grasshoppers to digest C4 grass BSC, leaf particles of Bouteloua curtipendula (Poaceae) were examined from the digestive tracts of two grasshopper species: Camnula pellucida (Scudder) (primarily a grass feeder) and Melanoplus sanguinipes (Fabricius) (a forb and grass generalist) (Orthoptera: Acrididae). Transmission electron microscopy was used to make the first observations of BSC crushing by herbivorous insects. Camnula pellucida and M. sanguinipes crushed over 58% and 24%, respectively, of the BSC in ingested leaf tissues. In addition, chloroplast and cell membranes were commonly disrupted in uncrushed BSC, permitting soluble nutrients to be extracted, even when BSC walls remain intact. The greater efficiency with which C. pellucida crushes BSC is consistent with the idea that grass‐feeding species are better adapted for handling grass leaf tissues than are generalist species. By demonstrating the effectiveness with which the BSC of B. curtipendula can be crushed and extracted by both species of grasshoppers, this study suggests one reason why C4 grasses are not generally avoided by grasshoppers: at least some C4 grasses can be more easily digested than has been hypothesized.
The sterile insect technique and the Mediterranean fruit fly: assessing the utility of aromatherapy in large field enclosures
Authors: Shelly Todd E. , McInnis Donald O. , Rendon Pedro
Published: August 2005

The sterile insect technique (SIT) is widely used in integrated programs against tephritid fruit flies, particularly the Mediterranean fruit fly, Ceratitis capitata Wiedemann (Diptera: Tephritidae). Unfortunately, the mass‐rearing procedures inherent to the SIT often lead to a reduction in the male mating competitiveness. One potential solution involves the prerelease exposure of males to particular attractants. In particular, male exposure to ginger root oil [Zingiber officinale Roscoe (Zingiberaceae); hereafter GRO], has been shown to increase mating success dramatically in field cage trials. To evaluate more rigorously the effectiveness of GRO exposure, we here describe two projects that compared levels of egg sterility or pupal yield, respectively, following the release of wild flies and either GRO‐exposed (treated) sterile males or GRO‐deprived (control) sterile males in large field enclosures. In both projects, sterile males from a genetic sexing strain were exposed as adults to GRO for 24 h while held in large storage boxes. In Hawaii, we dissected eggs from fruits to determine the percentage of egg hatch at four overflooding ratios, ranging from 5 : 1 to 60 : 1 (sterile : wild males), and found that, at all four ratios, the proportion of unhatched (sterile) eggs was significantly greater in enclosures containing GRO‐exposed males than control males. In Guatemala, we allowed larvae to develop in fruits and counted the number of pupae produced. At the only overflooding ratio tested (25 : 1), pupal yield was approximately 25% lower for enclosures containing GRO‐exposed males than control males, although this difference was not statistically significant. An explanation for the differing outcomes is proposed, and the implications of these findings for the SIT are discussed.
Partial characterization of the proteolytic enzymes in the gut of the banana weevil, Cosmopolites sordidus, and effects of soybean Kunitz trypsin inhibitor on larval performance
Authors: Montesdeoca M. , Lobo M. G. , Casañas N. , Carnero A. , Castañera P. , Ortego F.
Published: August 2005

The proteolytic enzymes in the gut of the banana weevil, Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae), have been characterized. Both larvae and adults rely on a complex proteolytic system based on at least cathepsin D‐, cathepsin B‐, trypsin‐, chymotrypsin‐, leucine aminopeptidase‐, carboxypeptidase A‐, and carboxypeptidase B‐like activities. All endoproteolytic activities were higher in the anterior section of the gut, whereas the exopeptidases were evenly distributed in the anterior and middle sections, and almost no activity was detected in the posterior section. Gelatin‐containing gels confirmed the spatial organization of the proteolytic digestive process. According to this proteolytic profile, the STI (soybean Kunitz trypsin inhibitor) was tested in vivo to establish its potential as a resistance factor against C. sordidus. Newly hatched larvae fed on diets containing 0.2% (w/w) STI experience lower survival rates and display significant reductions in larval growth. Biochemical analysis carried out on guts of larvae reared on STI‐treated diet showed a reduction of trypsin‐like activity compared to that from larvae fed on control diet. This decrease was compensated with an induction of cathepsin B, whereas cathepsin D, chymotrypsin, and leucine aminopeptidase were not affected. These results are discussed as a basis for selecting appropriate inhibitors to obtain transgenic banana and plantain plants with enhanced resistance to this pest.
Formation of melanin‐based wing patterns is influenced by condition and immune challenge in Pieris brassicae
Authors: Freitak Dalial , Vanatoa Alo , Ots Indrek , Rantala Markus J.
Published: August 2005

According to life‐history theory, trade‐offs emerge because organisms possess a limited amount of resources that they have to allocate between different bodily functions. Here, we tested whether there is a trade‐off between melanin‐based immune response and dark melanized wing patterning in the large white butterfly, Pieris brassicae L. (Lepidoptera: Pieridae), by activating the immune system of pupae and measuring the wing pigmentation of freshly emerged adults. In contrast to expectations, we did not find any negative associations between immune challenge and wing patterning. Furthermore, implanted and punctured male pupae tended to have larger and darker forewing tips as adults compared to controls. Both in females and males, different wing spots were affected by condition‐reflecting traits (e.g., pupal mass, brood), which suggest that formation of wing patterns may be a condition‐dependent process and/or heritable.
An inverse demand analysis with introduction of quality effects: an application to Spanish consumption of fruit and vegetables
Authors: Galdeano Emilio
Published: August 2005

This article analyzes consumer preference for fruit and vegetables when, by using time series with socioeconomic characteristics of households, there can be seemingly unobserved quality effects, which are increased by aggregation. The changes in Spanish demand for fresh and processed fruit and vegetables over the period 1987–2000 are discussed. Following previous tests and analyses, quantities are taken as predetermined and prices as matching the offer conditions. Thus, quality effects (based on the nutritional and/or health value of the product) are estimated from the error terms associated with the functions of the unit values. Quality variables are introduced as taste shifters in the inverse demand system (Laitinen–Theil model). The results show the positive effects of quality differences on the normalized price for the group of products through own‐quality flexibilities, and the negative effects between fresh and processed products through cross‐quality flexibilities.
The conditions of collective action for local commons management: the case of irrigation in the Philippines
Authors: Fujiie Masako , Hayami Yujiro , Kikuchi Masao
Published: August 2005

We examine factors affecting the success and failure of collective action toward the management of local commons. Using cross‐section survey data on the activities of irrigators' associations in the Philippines, regression analysis is conducted to identify factors underlying the success and failure in farmers' organizing collective action for the maintenance and operation of irrigation systems. We find that collective action is difficult to organize where (a) water supply is uniformly abundant; (b) water supply is greatly different between upper and lower streams in lateral; (c) the size of the association is large; (d) population density is low; (e) the share of nonfarm households is high; and (f) the history of irrigated farming is short. Our findings suggest that these difficulties can be overcome with adequate supports of state agencies to promote community‐level cooperation.
The role of agricultural entrepreneurship in Dutch agriculture of today
Authors: De Lauwere C. C.
Published: August 2005

It is thought that agricultural entrepreneurs have an important role to play in Dutch agriculture. They are currently being confronted with drastic changes and it is open to question whether or not they are willing and able to deal with such changes. A telephone survey was carried out in order to find an answer to this question. The data presented here are based on the answers from 752 farmers. The questions to be answered were: (1) Which strategies do agricultural entrepreneurs choose to keep up with business demands? (2) Which personal characteristics are related to these choices and to successful agricultural entrepreneurship in general? (3) Do agricultural entrepreneurs in the Netherlands meet the demands of “real” entrepreneurship according to economic theories? Agricultural entrepreneurship was conceptualized into the strategic orientations, social orientation, growth orientation, and financial conservatism. The data showed that five different types of farmers could be distinguished on the basis of their preferences for different strategic orientations. Social farmers had especially high scores for social orientation, traditional growers for growth orientation, prudent farmers for financial conservatism, new growers for both social orientation and growth orientation, and indecisive farmers for all strategic orientations. The latter group was eliminated from the data because farmers in this group had the highest scores for almost all items of the questionnaire, whether or not these concerned positive or negative aspects of entrepreneurship. Moreover, they gave contradictory answers to comparable questions. Based on future expectations and family income, it was concluded that social farmers and new growers were more successful than other farmers. According to economic theories, they also seemed to meet the “demands” of “real” entrepreneurship better than other farmers because they can be called “movers of the market,”“innovators,” and/or “discoverers of profit opportunities.” New growers and social farmers were also distinguishable from the other groups of farmers by their personal characteristics. In general, it could be concluded that positive personal characteristics (self‐criticism, leadership, creativity, perseverance, and initiative) affected agricultural entrepreneurship positively, and negative personal characteristics (love of ease and passivity) affected it negatively.
Empirical measurement of credit rationing in agriculture: a methodological survey
Authors: Petrick Martin
Published: August 2005

Empirical analysis of rural credit market failure has been of key scientific and political interest in recent years. The aim of this article is to give an overview of the various methods for measuring credit rationing that are employed in the literature. Furthermore, the methods are subjected to a comparative evaluation of their specific strengths or shortcomings. Six approaches are distinguished: measurement of loan transaction costs, analysis of qualitative information collected in interviews, analysis of quantitative information collected in interviews using the credit limit concept, analysis of spill‐over effects with regard to secondary credit sources, econometric household modeling, and the econometric analysis of dynamic investment decisions. An explicit comparison with a first‐best solution is impossible in the first three approaches, since they essentially rely on a subjective assessment of borrowers' access to credit, based on qualitative or quantitative indicators. The fifth and sixth approaches allow a rigorous interpretation in the framework of neoclassical equilibrium theory. The fourth approach takes an intermediate position, since spill‐over on segmented loan markets reveals a willingness to pay with regard to the supposedly less expensive but rationed primary source. The approaches are fairly data demanding in general, usually requiring specific data on loan transactions. Even so, most approaches are applicable to cross‐sectional household data. With the exception of the first, all methods surveyed might plausibly be used to empirically detect credit rationing.
Intertemporal analysis of employment decisions on agricultural holdings in Slovenia
Authors: Juvančič Luka , Erjavec Emil
Published: August 2005

The article attempts to quantify determinants influencing the dynamics of employment decisions on agricultural holdings in Slovenia and to test specific aspects of labor reallocation during the transition period by the application of an agricultural household model. Through the use of a 1991–2000 longitudinal data set for 22,055 farm households, quantitative analysis of intertemporal employment decisions by farm holders is carried out using probit techniques. The determinants tested relate to the personal characteristics of farm holders (gender, age, education level, and potential off‐farm income), household characteristics (size, structure), characteristics of the agricultural holding (economic size, labor intensity), and local labor market conditions. The model results generally confirm existing empirical evidence on asymmetrical and irreversible participation of holders on the labor market. Despite intensive restructuring of agriculture and profound changes in the nonfarm labor market in the analyzed period, labor supply of farm holders remains rigid. The mobility of labor supply is lower than expected, which can be attributed to the importance of structural problems constraining intersectoral mobility. Low labor mobility reduces the efficiency of labor allocation on agricultural holdings in Slovenia. Elements of this problem emerge on both supply (e.g., low level of educational and professional attainment of reference persons) and demand sides of the labor market (e.g., unfavorable local labor market conditions). A marked tendency toward maintaining the same employment status is more distinct in the case of holders employed on‐farm only.
Exploring the benefits of user education: a review of three case studies
Authors: Murphy Jeannette , Adams Anne
Published: August 2005

This paper builds on Leslie Morton's vision of enabling users through education and training. It describes three different approaches to mediated training for medical students and clinicians provided by peers, juniors (i.e. medical students) and information specialists (i.e. clinical librarians) and considers the benefits to the participants. The training was provided either on a one‐to‐one basis or within teams in their work environments (e.g. offices, wards, team meetings). The first two projects (peer tutoring and reverse mentoring) suggest that contextualized training, using intermediaries, provides the direct benefit of cost‐effective IT skill development and the indirect benefits deriving from the interactions between the trainers and the target groups. The third project, the outreach librarian study, provides evidence of both direct benefits (i.e. time saved, quality of service, skills acquired, financial savings and improved evidence‐based medicine implementation) and indirect, long‐term benefits relating to more social issues (e.g. perceptions of the library, clinical teams, job satisfaction and patient interactions). The general conclusion to emerge from this review of case studies is that the concept of educational benefits is very broad and that empirical studies need to look at both obvious and less obvious benefits.
medline in the UK: pioneering the past, present and future
Authors: Pritchard Steve J. , Weightman Alison L.
Published: August 2005

This article provides a brief history of the development of the medline database and its huge impact within the UK, from its inception to the present time. The origins of medline can be traced back to a collection of books in the US Surgeon General's Office during the American Civil War and John Shaw Billings’ decision, during 1867, to make this Library as complete as possible. From these beginnings, Index Medicus was developed in the early years of the 20th century, and electronic versions of the database began with the computerized on‐demand search service MEDLARS in 1964 and then via CD‐ROM and Internet Grateful Med to the web‐based and free‐to‐all service, PubMed, in 1997. The response to PubMed was immediate and startling with usage increasing from 7 million searches per annum in 1996 to 400 million searches per annum in 2001 and the service continues to improve. medline providers are now offering mapping of natural language queries to the sophisticated indexing vocabulary (Medical Subject Headings, MeSH) and the provision of specific filters for different types of publication to improve searching efficiency, as well as links to full‐text versions of the papers where available. The next steps are likely to involve an increased blurring of database and full‐text boundaries, incorporating seamless access to the best available evidence within medline and a wide range of other information resources within a single search and to an increasing amount of full‐text via various open‐archive initiatives. As ever, the US National Library of Medicine is in the vanguard of research and further applications of its medline database for users within the UK will be awaited with great interest.
The increasing globalization of health librarianship: a brief survey of international trends and activities
Authors: Madge Bruce , Plutchak T. Scott
Published: August 2005

Background and purpose:   Throughout his career, Leslie Morton was interested in international developments in health librarianship. In memory of the work he did in this field, the authors examine current developments in international health librarianship and describe some current themes.

Procedures:   The authors draw from their combined experience in international activities and the published information available from selected library associations and related organizations.

Findings:   Although many of the major health library associations around the world are tackling agendas specific to their own country, issues of international concern are emerging in common. These are grouped around globalization, partnerships and co‐operation, electronic access, especially open access, and working with the developing world in a number of different ways. Of course, the basis of all of these initiatives is to improve the health of the population by providing the best possible access to materials.

Conclusions:   Professional associations can provide a useful institutional infrastructure for addressing issues of international interest. Librarians should encourage their associations to develop these international initiatives and to seek out new and innovative ways to work together across international boundaries.
The way we were: health library life seen through the pages of the Medical Library Bulletin of the Thames Regions, 1974–94
Authors: Sawers Caroline
Published: August 2005

The Medical Library Bulletin of the Thames Regions reflected the development of health‐service libraries over the 20 years it existed. Originally begun as a practical aid to improving services by encouraging co‐operation, improving communication and giving instructive advice, it charted the work of health‐service librarians and the growth of their services. The articles contained in it covered professional developments and wider political issues as they occurred, and illustrated the extension of the librarians’ knowledge and skills. Leslie Morton, Library Adviser to the British Postgraduate Medical Federation, edited almost every issue, starting at a time when there was little guidance or professional literature available for health‐service librarians.
The professionalization of health librarianship in the UK between 1909 and 1978
Authors: Ferguson Valerie
Published: August 2005

Many strands exist within health information work and during the last century librarians in this field identified themselves through special groups or associations. This paper focuses on the key role of the Library Association Medical Section in the professional development of medical librarians in the United Kingdom up to 1978 when it merged with the Library Association Hospital Libraries and Handicapped Readers Group to create the Medical, Health and Welfare Group. Uniting to form a stronger organization, under the ultimate designation of the Health Libraries Group, was part of an evolutionary process. The invention and promotion of co‐operative schemes, networking and educational opportunities for members, the publication of specialized material and the fostering of international relationships during the first three‐quarters of the century are illuminated by personal reminiscences from some of the major participants in the field.