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Heat and odour production can have profound effects on pollination in cycads. It is therefore expected that these traits would co-vary geographically with pollinator assemblages. Such intraspecific variation, may lead to the evolution of pollination ecotypes, which can be an early stage of pollinator-mediated speciation. We measured cone temperatures using miniature temperature data loggers and examined the composition of cone volatile odours using headspace sampling and analysis with gas chromatography-mass spectrometry in four populations spanning the range of the African cycad Encephalartos ghellinckii. Pollinator assemblages were also investigated in three populations. Male and female cones were thermogenic at pollen shed and receptive stages, respectively, but patterns of thermogenesis did not vary among populations. Scent emissions from cones in populations in the Drakensberg Mountains were characterised by cis-β-ocimene, β-myrcene and (3E)-1,3-octadiene, while camphene and α-pinene were characteristic of scent emissions from cones in populations closer to the coast. These differences in volatile blends corresponded with differences in insect assemblages. These results confirm intraspecific variation in volatile emissions of E. ghellinckii and support the predictions that intraspecific variation in volatile emissions will be associated with shifts in pollinator assemblages. While further work needs to be done to test for local adaptation in this system, this preliminary evidence is consistent with the formation of pollination ecotypes in the E. ghellinckii species complex., (© 2017 German Society for Plant Sciences and The Royal Botanical Society of the Netherlands.)

Rewardless plants can attract pollinators by mimicking floral traits of rewarding heterospecific plants. This should result in the pollination success of floral mimics being dependent on the relative abundance of their models, as pollinator abundance and conditioning on model signals should be higher in the vicinity of the models. However, the attraction of pollinators to signals of the models may be partially innate, such that spatial isolation of mimics from model species may not strongly affect pollination success of mimics. We tested whether pollination rates and fruit set of the rewardless orchid Disa pulchra were influenced by proximity and abundance of its rewarding model species, Watsonia lepida. Pollination success of the orchid increased with proximity to the model species, while fruit set of the orchid increased with local abundance of the model species. Orchids that were experimentally translocated outside the model population experienced reduced pollinaria removal and increased pollinator-mediated self-pollination. These results confirm predictions that the pollination success of floral mimics should be dependent on the proximity and abundance of model taxa, and thus highlight the importance of ecological facilitation among species involved in mimicry systems., (© 2017 German Botanical Society and The Royal Botanical Society of the Netherlands.)

Plants are expected to emit floral scent when their pollinators are most active. In the case of long-tubed flowers specialised for pollination by crepuscular or nocturnal moths, scent emissions would be expected to peak during dawn. Although this classic idea has existed for decades, it has rarely been tested quantitatively. We investigated the timing of flower visitation, pollination and floral scent emissions in six long-spurred Satyrium species (Orchidaceae). We observed multiple evening visits by pollinaria-bearing moths on flowers of all study species, but rarely any diurnal visits. The assemblages of moth pollinators differed among Satyrium species, even those that co-flowered, and the lengths of moth tongues and floral nectar spurs were strongly correlated, suggesting that the available moth pollinator fauna is partitioned by floral traits. Pollinarium removal occurred more frequently during the night than during the day in four of the six species. Scent emission, however, was only significantly higher at dusk than midday in two species. Analysis of floral volatiles using gas chromatography coupled with mass spectrometry yielded 168 scent compounds, of which 112 were species-specific. The scent blends emitted by each species occupy discrete clusters in two-dimensional phenotype space, based on multivariate analysis. We conclude that these long-spurred Satyrium species are ecologically specialised for moth pollination, yet the timing of their scent emission is not closely correlated with moth pollination activity. Scent composition was also more variable than expected from a group of closely related plants sharing the same pollinator functional group. These findings reveal a need for greater understanding of mechanisms of scent production and their constraints, as well as the underlying reasons for divergent scent chemistry among closely related plants., (© 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.)

Hermaphroditism can lead to both intra- and intersexual conflict between male and female gender functions. However, the effect that such gender conflicts have on pollination efficiency has seldom been investigated. By artificially reducing the number of available male gametes on an individual, we quantified whether male interference with pollination efficiency occurs in the self-compatible, moth-pollinated orchid Satyrium longicauda. We partially emasculated S. longicauda inflorescences and compared pollination success and fecundity in these plants to intact controls. Pollen in both groups of plants was colour-labelled so that its dispersal by pollinators could be tracked directly in the field. Intact flowers on partially emasculated inflorescences exported more pollen and received more cross-pollen and less self-pollen than those on intact inflorescences. Proportion of fruit set per plant was similar between the two treatments; however, fruits on partially emasculated plants had proportionally more viable seeds than those on intact controls. These results provide empirical evidence that male interference with pollination efficiency can occur in a hermaphroditic plant and that such interference can compromise fecundity. The most likely mechanism for such male interference is competition for placement on the proboscis of hawkmoth pollinators. Consequently, male competition for siring success may influence the evolution of sexual systems in hermaphroditic pollinator-dependent plants., (© 2014 The Authors. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.)

Evolutionary shifts between pollination systems are often accompanied by modifications of floral traits, including olfactory cues. We investigated the implications of a shift from passerine bird to beetle pollination in Protea for floral scent chemistry, and also explored the functional significance of Protea scent for pollinator attraction. Using headspace sampling and gas chromatography-mass spectrometry, we found distinct differences in the emission rates and chemical composition of floral scents between eight bird- and four beetle-pollinated species. The amount of scent emitted from inflorescences of beetle-pollinated species was, on average, about 10-fold greater than that of bird-pollinated species. Floral scent of bird-pollinated species consists mainly of small amounts of "green-leaf volatiles" and benzenoid compounds, including benzaldehyde, anisole and benzyl alcohol. The floral scent of beetle-pollinated species is dominated by emissions of linalool, a wide variety of other monoterpenes and the benzenoid methyl benzoate, which imparts a fruity odour to the human nose. The number of compounds recorded in the scent of beetle-pollinated species was, on average, greater than in bird-pollinated species (45 versus 29 compounds, respectively). Choice experiments using a Y-maze showed that a primary pollinator of Protea species, the cetoniine beetle Atrichelaphinis tigrina, strongly preferred the scent of inflorescences of the beetle-pollinated Protea simplex over those of the bird-pollinated sympatric congener, Protea roupelliae. This study shows that a shift from passerine bird- to insect-pollination can be associated with marked up-regulation and compositional changes in floral scent emissions., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Combining biogeographic, ecological, morphological, molecular and chemical data, we document departure from strict specialization in the fig-pollinating wasp mutualism. We show that the pollinating wasps Elisabethiella stuckenbergi and Elisabethiella socotrensis form a species complex of five lineages in East and Southern Africa. Up to two morphologically distinct lineages were found to co-occur locally in the southern African region. Wasps belonging to a single lineage were frequently the main regional pollinators of several Ficus species. In South Africa, two sister lineages, E. stuckenbergi and E. socotrensis, pollinate Ficus natalensis but only E. stuckenbergi also regularly pollinates Ficus burkei. The two wasp species co-occur in individual trees of F. natalensis throughout KwaZulu-Natal. Floral volatile blends emitted by F. natalensis in KwaZulu-Natal were similar to those emitted by F. burkei and different from those produced by other African Ficus species. The fig odour similarity suggests evolutionary convergence to attract particular wasp species. The observed pattern may result from selection for pollinator sharing among Ficus species. Such a process, with one wasp species regionally pollinating several hosts, but several wasp species pollinating a given Ficus species across its geographical range could play an important role in the evolutionary dynamics of the Ficus-pollinating wasp association.

The pollen of hermaphrodite plants is often utilised by flower-visiting animals. While pollen production has obvious benefits for plant male fitness, its consequences for plant female fitness, especially in self-incompatible hermaphrodite species, are less certain. Pollen production could either enhance seed production though increased pollinator attraction, or reduce it if ovules are discounted by deposition of self pollen, as can occur in species with late-acting self-incompatibility. To test the effects of pollen reward provision on female fitness, we artificially emasculated flowers in two populations of the succulent Aloe maculata (Asphodelaceae), which has a late-acting self-incompatibility system, over the course of its flowering period. Flowers of this species are visited by sunbirds (for nectar) and native bees (for pollen and nectar). We measured floral visitation rates, floral rejection rates, pollen deposition on stigmas and fruit and seed set in both emasculated and non-emasculated plants. We found that flowers of emasculated plants suffered reduced visitation and increased rejection (arrival without visitation) by bees, but not by sunbirds; had fewer pollen grains deposited on stigmas and showed an overall decrease in fruit set and seed set. Rates of seed abortion were, however, greatly reduced in emasculated flowers. This study shows that pollen rewards can be important for seed set, even in self-incompatible plants, which have been assumed to rely on nectar rewards for pollinator attraction. Seed abortion was, however, increased by pollen production, a result that highlights the complexity of selection on pollen production in hermaphrodite flowers., (© 2011 German Botanical Society and The Royal Botanical Society of the Netherlands.)

Background and Aims: Floral scent may play a key role as a selective attractant in plants with specialized pollination systems, particularly in cases where floral morphology does not function as a filter of flower visitors. The pollination systems of two African Eucomis species (E. autumnalis and E. comosa) were investigated and a test was made of the importance of scent and visual cues as floral attractants., Methods and Key Results: Visitor observations showed that E. autumnalis and E. comosa are visited primarily by pompilid wasps belonging to the genus Hemipepsis. These wasps carry considerably more Eucomis pollen and are more active on flowers than other visiting insects. Furthermore, experiments involving virgin flowers showed that these insects are capable of depositing pollen on the stigmas of E. autumnalis, and, in the case of E. comosa, pollen deposited during a single visit is sufficient to result in seed set. Experimental hand-pollinations showed that both species are genetically self-incompatible and thus reliant on pollinators for seed set. Choice experiments conducted in the field and laboratory with E. autumnalis demonstrated that pompilid wasps are attracted to flowers primarily by scent and not visual cues. Measurement of spectral reflectance by flower petals showed that flowers are cryptically coloured and are similar to the background vegetation. Analysis of headspace scent samples using coupled gas chromatography-mass spectrometry revealed that E. autumnalis and E. comosa scents are dominated by aromatic and monoterpene compounds. One hundred and four volatile compounds were identified in the floral scent of E. autumnalis and 83 in the floral scent of E. comosa, of which 57 were common to the scents of both species., Conclusions: This study showed that E. autumnalis and E. comosa are specialized for pollination by pompilid wasps in the genus Hemipepsis and achieve specialization through cryptic colouring and the use of scent as a selective floral attractant.

The effects of the Agrobacterium rhizogenes rolB oncogene on apomixis were examined in the facultative apomictic plant Hieracium piloselloides because the oncogene has been shown to alter plant growth, morphogenesis and cellular sensitivity to auxin. Introduction of rolB under the control of either its own promoter or the CaMV35S promoter induced ectopic meristem formation from the inflorescence, confirming in planta a meristem-inducing role for this oncogene previously observed only in tissue culture. These ectopic meristems formed vegetative rosettes and floral plant organs. Upon immersion in water these meristems generated roots, suggesting that meristem commitment towards the generation of a specific organ type is a separate and later event that is dependent upon the developmental context. Ovule identity and form was altered in ectopically induced florets in plants expressing the CaMV35S::rolB construct. In contrast to the ovules of untransformed apomictic plants, the sexual process ceased earlier, prior to meiosis, yet surprisingly, apomixis initiated from a greater number of cells, and embryos and endosperm continued to develop in the structurally altered ovules. The alternative possibilities that the effects on reproduction might result from rolB influencing cellular response to auxin, or from alterations in cell signaling caused by changes in ovule morphology that are induced because of the expression of the oncogene are discussed.

Field studies in the semiarid Succulent Karoo region of South Africa showed that flowers of Massonia depressa (Hyacinthaceae) are visited at night by at least four rodent species, including two gerbil species. Live-trapped rodents were found to carry Massonia pollen on their snouts; they also had large quantities of Massonia pollen in their feces as a result of grooming their fur. Visits by insects to the flowers were infrequent at one site and apparently absent at another site. Plants enclosed in large-mesh wire cages, which excluded rodents but not insects, set very few seeds relative to open controls. Our initial hypothesis of rodent-pollination in M. depressa was based on the striking similarity of its flowers to those of unrelated, rodent-pollinated Protea species. Convergent traits include dull-colored and very robust flowers situated at ground level, a strong yeasty odor, and secretion of copious amounts of sucrose-dominant nectar during the evening when rodents are active. Despite having a low sugar concentration (∼20%), the nectar of M. depressa is almost 400 times as viscous as an equivalent sugar solution. The jelly-like constituent in the nectar may discourage robbing by insects, while also facilitating lapping by rodents. Our findings illustrate the utility of floral syndromes for generating testable predictions about pollination systems.

The authors surveyed by telephone a random sample of voters in the 1996 presidential election from the Standard Metropolitan Statistical Area of Muncie, IN ("Middletown"; R. Lynd & H. Lynd, 1929) to test a model describing the nature of 2 conservative political ideologies--social traditionalism and economic conservatism. The model, based on functions of attitudes theory, predicted (a) that the 2 political ideologies would appeal to 2 rather distinct constituency groups--the former, to conservative Protestants; the latter, to people of higher incomes--and (b) that social traditionalists would be more dogmatic and economic conservatives would be more open-minded in their respective views. The findings were consistent with those predictions.

The present study investigated the effect on witness confidence and accuracy of confusing questions often used by attorneys in court. Participants viewed a videotaped film and were individually questioned about the incident 1 week later. Half the participants were asked questions using six categories of confusing questions (negatives, double negatives, leading, multiple questions, complex syntax, and complex vocabulary); the remaining half were asked for the same information using simply phrased equivalents. Confusing questions reduced participant-witnesses' accuracy and suppressed confidence-accuracy relationships compared with the condition where simplified alternatives were asked. Witness performance was impaired by the fact that mock-witnesses rarely asked for a confusing question to be explained or qualified their answers. This experiment demonstrates the importance of ensuring that lawyers ask witnesses simple, clear, questions.

For a single-dose toxicity assessment, five patients with recurrent malignant glioma (ages 29-46 years) were treated with intracavitary alloreactive cytotoxic T lymphocytes (CTL) and interleukin-2 (IL-2). The trial tested the hypothesis that alloreactive CTL, sensitized to the major histocompatibility complex (MHC) proteins of the patient, offer selective, targeted killing of glioma cells that express MHC. Patient lymphocytes, which also express MHC, were irradiated and placed into CellMax artificial capillary systems with lymphocytes from MHC-disparate donors and CTL developed over a 2- to 3-week period with a low concentration of IL-2. The CTL largely expressed CD3 and CD11a/CD8 markers and lysed targets displaying patient MHC. CTL were implanted into the tumor bed at surgery and a catheter was used for subsequent infusions. Patients received one to five treatment cycles every other month; one cycle generally consisted of two or three CTL infusates administered within a 1- to 2-week period. Different unrelated donors were used for each cycle. Treatment was well tolerated; transient toxicity at grades 1-3 was recorded by NCI Common Toxicity Scale criteria. Two glioblastoma patients have died; one from tumor recurrence locally and the other from recurrence at a site distant from the treatment. Two of the five patients completed five cycles; one anaplastic oligodendroglioma patient shows no evidence of tumor 30 months from the start of immune therapy and an anaplastic astrocytoma patient shows stable disease 28 months after initiation of therapy. One anaplastic oligodendroglioma patient, who dropped the protocol during her second treatment cycle, has no evidence of tumor 28 months after recurrence.

Field studies in South Africa showed that floral spur length in the Disa draconis complex (Orchidaceae) varies enormously between populations in the southern mountains (means = 32-38 mm), lowland sandplain (mean = 48 mm), and northern mountains (means = 57-72 mm). We tested the hypothesis that divergence in spur length has resulted from selection exerted through pollinator proboscis length. Short-spurred plants in several southern mountain populations, as well as long-spurred plants in one northern mountain population, were pollinated by a horsefly, Philoliche rostrata (Tabanidae), with a proboscis length that varied from 22 to 35 mm among sites. Long-spurred plants on the sandplain were pollinated by the tanglewing fly, Moegistorynchus longirostris (Nemestrinidae), which has a very long proboscis (mean = 57 mm). Selection apparently favors long spurs in sandplain plants, as artificial shortening of spurs resulted in a significant decline in pollen receipt and fruit set, although pollinaria removal was not significantly affected. Fruit set in the study populations was limited by pollen availability, which further suggests that selection on spur length occurs mainly through the female component of reproductive success., (© 1997 The Society for the Study of Evolution.)

Background: A number of lifestyle factors are important in the etiology of basal cell carcinoma. Previous studies have investigated smoking, alcohol, diet, and sun exposure as possible contributing factors. No previous studies have investigated case-controlled lifestyle influences in basal cell carcinomas referred for Mohs micrographic surgery., Methods: Cases were obtained from Mohs-referred basal cell carcinoma patients. Matched controls were selected from a busy dermatology clinic. The only criteria for selection of controls was never having had cancer previously. Cases and controls were surveyed regarding lifestyle characteristics., Results: Forty-six age, sex, and skintype-matched controls were compared. Sun exposure, alcohol, and smoking were not significant factors. Dietary fat, fiber, and the vitamins A, C, and beta carotene, as well as selenium showed important, but not significant differences. Caffeine consumption was higher in the cancer group., Conclusions: Our findings agree with previously published studies in regard to antioxidant consumption as a protective factor for basal cell carcinoma. Caffeine consumption was higher in the cancer patients.

This study was done to integrate previous work on discriminatory tendencies against those who have AIDS and the possible role of two new variables, perceived responsibility and God's retribution. Using interview data from 205 randomly selected respondents from "Middletown" (Muncie, Indiana), an empirical model was developed. Ratings on homosexual intolerance had the biggest influence on tendencies toward discrimination against AIDS. This type of intolerance was confirmed as a part of a traditional and politically conservative perspective in which the ideas that those with AIDS are responsible for their predicament and God punishes those who sin play an important role.

Past research suggests that public support for the use of animal models as means to improve the human condition is present but many individuals have expressed ambivalence. In the present study, various sectors of the academic community (students and faculty) as well as the general population, were surveyed to assess their positions on the need for, and value of animal research, the value of psychological research in which animals are employed, and the respondents' consummatory habits. The results suggested that more information needs to be provided about the role of animal experimentation, including a discussion of the benefits produced by using animals to answer psychological questions.

The biocompatibility of radiofrequency plasma polymerized films (less than 100 nm thick) deposited on biomedical polymer supports has been characterized by in vitro and in vivo methods. The polymer interface materials covered a wide range of elemental composition and surface properties, and were prepared from N-vinyl-2-pyrrolidone, gamma-butyrolactone, n-hexane, and hexamethyldisilazane (PPHMDSZ). The biocompatibility studies showed that the interface materials were noncytotoxic to mouse and human fibroblasts, as shown by morphologic evaluation, and by determination of extracellular LDH; and they did not stimulate interleukin-1-like production from human monocytes, as indicated by a thymocyte proliferation assay. The human fibroblast proliferation assay showed that three of the polymers supported cell growth at levels comparable to, or greater than, polymer controls, while the hydrophobic PPHMDSZ inhibited both cell attachment and proliferation. The response to subcutaneous implantation for all test materials was indicative of biocompatibility, with rapid resolution of the acute phase response and normal wound healing. The wide range of composition and surface properties for the plasma polymerized films evaluated in this study suggest that this general class of materials is likely to exhibit excellent biocompatibility.

The developmental tasks of adolescence are discussed as a factor in some adolescents' risky sexual activity, which may lead to pregnancy. This theory is presented in the context of a case study. Nursing diagnoses, possible interventions, and nursing implications are examined in relation to assisting at-risk teens to meet their developmental needs. It is hoped that this article will stimulate further dialogue in the literature of developmental causes of teenage pregnancy, identification of those at risk, and appropriate nursing responses.

A hydrophilic polymer composite film (approx. 420 nm thick), with potential application as an interface for biomaterials has been prepared on nonorganic substrates, which include glass, silicon, and aluminum foil, using a glow discharge plasma polymerization technique. A thin film (110 nm thick) polymerized from hexane provided an adherent protective coating for the substrate material, and covalent bonding sites for the outer layer polymerized from N-vinyl-2-pyrrolidone. This outer layer provided the hydrophilic surface or interface. The two layers were copolymerized for a short period during transition between monomers to provide an intimate covalently bonded diffuse interphase. Preliminary in vitro and in vivo biocompatibility studies indicate that the hydrophilic film is non-cytotoxic, and does not increase the inflammatory response when compared with negative controls.

Investigation of an outbreak of hepatitis in Dhaka implicated enterically transmitted non-A, non-B (ET-NANB) hepatitis as the etiologic agent. This observation was made by exclusion in 17 of 19 patients, and confirmed serologically in one randomly selected patient by a fluorescent antibody blocking assay specific for ET-NANB hepatitis. These findings reinforce earlier suspicions that ET-NANB may be an important cause of acute hepatitis in Bangladesh. The epidemiology of ET-NANB hepatitis is discussed, and public health recommendations are made.

We have confirmed that two closely related circular RNA molecules previously named grapevine yellow speckel viroid (GYSV) and grapevine viroid 1B (GV1B) are indeed viroids. Electron microscopy after spreading under non-denaturing conditions revealed that GYSV has a rod-like structure typical of viroids. Purified GYSV and GV1B replicated independently in inoculated grapevine seedlings and some of the infected plants developed yellow speckle symptoms indicating that both viroids can cause grapevine yellow speckle disease. Plus-sense RNA transcripts derived from a dimeric GYSV cDNA clone induced yellow speckle symptoms in a grapevine seedling confirming the role of GYSV in the yellow speckle disease. Two oligonucleotide probes were synthesized for the detection of the two related viroids. The probes which could detect each viroid individually were used to assess correlations between the occurrence of these viroids and the incidence of the disease.

Coagulation and need for postoperative blood and plasma therapy were studied in 94 injured patients requiring massive transfusions (average = 14.4); 46 patients, by random selection, received supplemental albumin. Albumin therapy increased total protein concentration (6.4 vs 5.8 g/dL), serum albumin level (4.2 vs 2.9 g/dL), and plasma volume (3,895 vs 3,579 mL) but not RBC volume (1,520 vs 1,530 mL). During the initial five postoperative days, patients receiving albumin required more transfusions (7.1 vs 3.8) and plasma (455 vs 317 mL). This increased need for blood and plasma correlated with a significant decrease in fibrinogen (238 vs 405 mg/dL) and prolongation of the prothrombin time (2.6 vs 1.4 seconds). The partial thromboplastin time was prolonged and the platelet concentration was decreased in albumin-treated patients, but not significantly. Deficiencies in specific coagulation factors have not yet been identified but are being studied. Impaired coagulation is another potential hazard of supplemental albumin therapy, which is probably contraindicated in injured patients.

Samples were taken from "Middletown" in 1985, 1986, and 1987 to assess tendencies to discriminate against AIDS victims and what factors were related to this tendency. A tendency to discriminate against AIDS victims has decreased significantly from 1985 to 1987, and those who are most likely to discriminate were members of the Christian Right and who have more of an individual than a community orientation.

The long-term follow-up of patients operated by one surgeon by simple anterior discectomy without fusion have been presented. The results are much better in patients with soft extruded discs than with painful discs or degenerative discs with varying degrees of radiculopathy or myelopathy. The same statement can be made for the posterior approach. The anterior approach appears to be superior for soft central extruded discs compressing the spinal cord. There appears to be a greater incidence of another disc at an adjacent level with the anterior approach than when the operation is done posteriorly. The anterior operation is an easier surgical procedure than the posterior operation in the average surgeon's hands; otherwise, it would not be as popular as it is. Interbody fusion has no long-term advantages over simple discectomy. Complications of the anterior approach, particularly with fusion, appear greater than the limited posterior approach. Rather than continue the controversy over the anterior vs. the posterior approach, it is recommended that each surgical case be evaluated to determine the preferred approach. With the passage of time, I have preferred to operate the C4, 5, and 6 ruptured discs anteriorly, as well as all central discs or hard central cervical spondylotic bars. This seems preferable to the extensive laminectomy recommended by many for spondylotic myelopathy. However, the anterior approach has been limited to two spaces rather than multiple spaces. On the rare occasions when an extensive decompression of the cervical canal is indicated, the posterior approach has been chosen. In addition, the C7 or rare T1 soft ruptured disc have been done posteriorly. When there is a doubt about the diagnosis, e.g., when a tumor is suspected or a multiple root defect associated with atypical findings on myelography, the posterior approach is preferred.

Aggression of each of 32 white male and female university students toward an opponent who had just defeated him in a competition was assessed in a 2 X 2 experiment design in which the winning opponent was either a black or a white and the loss was for one or two reasons: because the opponent 1) was economically deprived or 2) had superior ability. It was assumed that those Ss who had lost to a black opponent because this person was economically deprived experienced reverse discrimination based on race. Results indicated that white Ss were more aggressive toward a black when the loss was based on economic deprivation (reverse discrimination) than towards a white when the loss was due to economic deprivation (an arbitrary loss but not based on race), whereas white Ss were less aggressive towards a black opponent than towards a white opponent when the Ss lost because of the other's superior ability. The practical and theoretical implications of these results are discussed.

Physicians in the State of Wisconsin were contacted by mail and asked to report all cases of diabetes in patients under 20 yr diagnosed between 1 July 1982 and 30 June 1984 in order to study factors associated with seasonality in insulin-dependent diabetes mellitus (IDDM). Wisconsin's population is fairly homogeneous and is primarily middle socioeconomic class, small-town or rural, and of northern European Caucasian descent. The incidence of IDDM in winter was higher than in summer during the first year of the study, similarly to results of other studies. However, there was no significant winter peak in diagnosis during the second year. When monthly incidence rates from both years were combined, the increased evidence of IDDM in winter vs. summer was evident in males, but not in females. There appeared to be a spike in the number of new cases of IDDM in the first year of the study which was more evident in males. Such a spike is consistent with spikes in the incidence of IDDM occurring about the same time in Europe and in North America. The percentage of patients with antibody titres to Coxsackie virus and mycoplasma pneumoniae diagnosed during the first winter's peak were equal to those in nondiabetic controls. The distributions of HLA DR types of patients diagnosed in winter were no different from diabetics diagnosed in other seasons. The distribution of HLA DR types (5% DR2, 55% DR3, 82% DR4 and 38% DR3DR4) were similar to those of other groups of Caucasian subjects with IDDM. Also similarly to other studies of IDDM, 14% of the patients had thyroid microsomal antibody titers. The results of this study support the previously-advanced idea that winter might precipitate overt carbohydrate intolerance in individuals in whom insulin cell destruction is already well established (Diabetes, 36, 265-268, 1987). If this is true, studies of seasonality in IDDM might not be informative about the causation of IDDM.

Teichuronic acid isolated from the cell walls of Micrococcus luteus has been examined by natural-abundance (13)C NMR spectroscopy. Proton-decoupled and proton-coupled spectra were obtained for native teichuronic acid and also after the teichuronic acid had been oxidized with periodate and reduced with borohydride. The spectra are consistent with the structure [ManNAcUAp-( beta -1,6)-G1cp-( alpha -1,4)]n. Teichuronic acid synthesized in vitro from suitable substrates by the particulate enzyme fraction obtained from M. luteus yielded a (13)C NMR spectrum which is indistinguishable from that of the native teichuronic acid, indicating a structural identity of the teichuronic acid synthesized in vitro with that isolated from cell walls.

The reliability and accuracy of two-compartment temporomandibular joint (TMJ) arthrography was compared with MR imaging on the basis of an analysis of surgical findings obtained from joints that had been studied preoperatively with arthrography or MR or, in some cases, both procedures. Seven hundred forty-three consecutive TMJ arthrograms were successfully obtained in a total of 443 patients by using a single 27-gauge needle and a two-compartment technique in each joint. There was a 100% correlation with surgical findings in 218 radiologically abnormal joints operated on within 90 days of arthrography with respect to the presence or degree of meniscus displacement and normal or abnormal disk morphology and function. In 604 patients 1052 TMJs were studied with high-field-strength surface-coil MR. Surgical findings were available for correlation in 170 of the joints studied. Forty-three joints were studied with both two-compartment arthrography and MR. Eight operated joints had been imaged successfully with both two-compartment arthrography and MR. Both methods of evaluation provided highly reliable and accurate information regarding meniscus position and shape. Arthrography was superior to MR in detecting capsular adhesions and the presence or absence of perforation of the disk or meniscus attachments. Simple meniscectomy (with or without insertion of a temporary Silastic TMJ implant) was the most frequently performed surgical procedure in the series, followed by meniscus repositioning procedures. Joint effusions, failed TMJ implants, and avascular necrosis were demonstrated best with MR. Soft-tissue lesions, including intrinsic degeneration of the meniscus, anomalous muscle development, muscle atrophy, tendinitis, and injuries such as contusions and hematomas, were demonstrated only with MR. Partial-flip-angle GRASS (gradient-recalled acquisition in the steady state) techniques permit both fast scanning and study of functional joint dynamic. Joint fluid may appear as high signal intensity on GRASS images because of T2*-weighting. We recommend MR as the procedure of choice for diagnosis of uncomplicated internal derangements of the TMJ. Two-compartment arthrography with videofluoroscopy is an important ancillary procedure that should be performed whenever capsular adhesions or perforations are suspected and not demonstrated with MR and whenever MR is inconclusive.

The effect of albumin when added to the resuscitation regimen of patients in hypovolemic shock was studied in a randomized prospective manner in 52 injured patients who received an average of 15.3 transfusions, 9.6 liters of balanced electrolyte solution, and 980 ml of fresh frozen plasma. Before and during operation, 27 patients received an average of 25 gm of albumin and 150 gm/day for three to five days. Patients who received albumin had greater dependence on respiratory support, averaging eight days while receiving ventilatory support with volume ventilator compared with three days in patients not receiving albumin. Furthermore, patients receiving albumin had forced inspiratory oxygen/Pao2 ratios that were statistically and significantly higher than those of patients not receiving albumin during all phases of their hospital course. These effects were associated with increased plasma volumes caused by the oncotic effects of albumin and by its interference with saline diuresis. On the basis of this preliminary report, albumin seems to have a detrimental effect on respiratory function.