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Background Operating a motor vehicle involves multiple cognitive and sensorimotor faculties. Neurological conditions pose driving risk, but this has not been examined in patients with primary brain tumors. Methods Sixty-four patients with primary brain tumors (32 left hemisphere; 69% glioblastoma) completed the Cognitive Behavioral Driver’s Inventory (CBDI). A subset also completed broader cognitive testing. Patient characteristics, CBDI measures, and broader neuropsychological test scores were compared between Passing and Nonpassing groups. Follow-up logistic regression analyses identified patient characteristics and CBDI measures predictive of Pass/Nonpass outcome. Point-biserial correlations determined associations between neuropsychological tests and CBDI outcome. Results Sixty-nine percent of patients were classified as passing the CBDI. Nonpassing patients were older and more likely to have WHO grade IV and temporal lobe tumors. Age was the most salient predictor of CBDI performance. CBDI measures of speeded visual search and set-shifting, speeded response inhibition, vigilance and freedom from distractibility, and basic visual scanning speed were predictive of Pass/Nonpass outcome. Neuropsychological tests of memory in particular, but also speeded visual scanning and discrimination, executive function, basic visual attention, visuoconstruction, and manual dexterity (dominant hand), were associated with CBDI outcome. Conclusions A sizeable proportion of patients with primary brain tumors appear at risk of driving difficulty, particularly those with higher-grade tumors and of older age. Memory, visual attention, and executive difficulties appear to contribute most to driving safety risk as determined by the CBDI. These results highlight the importance of driving safety screening in this population.

Background Cancer and treatment-related neurocognitive dysfunction has the potential to significantly disrupt the lives of survivors. While neurocognitive functioning is known to predict aspects of patient-reported quality of life in individuals with glioma, little is known regarding the association between neurocognitive functioning and clinician-rated functional independence. Methods Newly diagnosed patients with glioma in the left (n = 73; 49% glioblastoma) or right (n = 30; 57% glioblastoma) temporal lobe completed comprehensive neuropsychological testing. Clinicians rated patient functional independence using the Functional Independence Measure (FIM) and Karnofsky Performance Status (KPS) scale. Correlational and regression analyses were conducted to determine relationships between neurocognitive functioning and functional independence. Results Tests of verbal learning, executive function, and language comprehension were moderately to strongly associated with clinician-rated functional independence, particularly for items pertaining to need for assistance with memory, problem-solving, and language functions. Stepwise linear regression showed that tests of verbal learning, executive functioning, and language comprehension predicted FIM ratings, together accounting for 40% of variance (P < .001). A test of executive functioning also predicted KPS scores and accounted for 19% of variance (P < .001). Conclusions In patients with newly diagnosed temporal lobe glioma, neurocognitive functioning is associated with functional independence. Verbal learning, executive functioning, and language comprehension demonstrated the strongest associations across both measures of functional independence. These findings provide support for the ecological validity of neuropsychological assessment by demonstrating the real-world clinical significance of objectively assessed neurocognitive functioning in glioma patients.

The main line of treatment for chronic wounds is the application of an appropriate dressing. Dressings can be used to reduce odour and pain, maintain a moist healing environment, remove excessive exudate and prevent clinical infection. Antimicrobial compounds such as silver, honey and iodine have been in use for millennia. The discovery of antibiotics in the early 20th century greatly reduced the routine usage of such compounds. More recently, there has been renewed interest in these compounds, with manufacturers adding these to dressings to provide greater antimicrobial action and aid the healing process. Much of the published literature on the antimicrobial properties of silver, honey and iodine-containing dressings is contradictory, with varying degrees of efficacy reported. This study aimed to independently compare the in vitro antimicrobial activity of a wide variety of dressings against common wound pathogens; Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa, in order to provide further evidence and aid dressing selection. Although no significant differences were reported between honey, iodine and silver; a significant difference was observed between the individual dressings, indicating that determination of bacterial species present within a wound can aid clinical staff in the selection of the most appropriate dressing.

In rare circumstances, scientists have been able to revive dormant propagules from ancestral populations and rear them with their descendants to make inferences about evolutionary responses to environmental change. Although this is a powerful approach to directly assess microevolution, it has previously depended entirely upon fortuitous conditions to preserve ancestral material. We propose a coordinated effort to collect, preserve, and archive genetic materials today for future studies of evolutionary change—a “resurrection paradigm.” The availability of ancestral material that is systematically collected and intentionally stored using best practices will greatly expand our ability to illuminate microevolutionary patterns and processes and to predict ongoing responses of species to global change. In the workshop “Project Baseline,” evolutionary biologists and seed storage experts met to discuss establishing a coordinated effort to implement the resurrection paradigm.

A wide variety of temperate animals rely on length of day (photoperiodism) to anticipate and prepare for changing seasons by regulating the timing of development, reproduction, dormancy, and migration. Although the molecular basis of circadian rhythms regulating daily activities is well defined, the molecular basis for the photoperiodic regulation of seasonal activities is largely unknown. We use geographic variation in the photoperiodic control of diapause in the pitcher-plant mosquito Wyeomyia smithii to create the first QTL map of photoperiodism in any animal. For critical photoperiod (CPP), we detect QTL that are unique, a QTL that is sex linked, QTL that overlap with QTL for stage of diapause (SOD), and a QTL that interacts epistatically with the circadian rhythm gene, timeless. Results presented here confirm earlier studies concluding that CPP is under directional selection over the climatic gradient of North America and that the evolution of CPP is genetically correlated with SOD. Despite epistasis between timeless and a QTL for CPP, timeless is not located within any detectable QTL, indicating that it plays an ancillary role in the evolution of photoperiodism in W. smithii. Finally, we highlight one region of the genome that includes loci contributing to CPP, SOD, and hormonal regulation of development.

This article presents a method for QTL interval mapping in autotetraploid species for a full-sib family derived by crossing two parents. For each offspring, the marker information on each chromosome is used to identify possible configurations of chromosomes inherited from the two parents and the locations of crossovers on these chromosomes. A branch and bound algorithm is used to identify configurations with the minimum number of crossovers. From these configurations, the conditional probability of each possible QTL genotype for a series of positions along the chromosome can be estimated. An iterative weighted regression is then used to relate the trait values to the QTL genotype probabilities. A simulation study is performed to assess this approach and to investigate the effects of the proportion of codominant to dominant markers, the heritability, and the population size. We conclude that the method successfully locates QTL and estimates their parameters accurately, and we discuss different modes of action of the QTL that may be modeled.

This article presents methodology for the construction of a linkage map in an autotetraploid species, using either codominant or dominant molecular markers scored on two parents and their full-sib progeny. The steps of the analysis are as follows: identification of parental genotypes from the parental and offspring phenotypes; testing for independent segregation of markers; partition of markers into linkage groups using cluster analysis; maximum-likelihood estimation of the phase, recombination frequency, and LOD score for all pairs of markers in the same linkage group using the EM algorithm; ordering the markers and estimating distances between them; and reconstructing their linkage phases. The information from different marker configurations about the recombination frequency is examined and found to vary considerably, depending on the number of different alleles, the number of alleles shared by the parents, and the phase of the markers. The methods are applied to a simulated data set and to a small set of SSR and AFLP markers scored in a full-sib population of tetraploid potato.

An earlier program, TetraploidMap, enabled linkage analysis to be performed for autotetraploid species, with a text-based input and output. The current program, TetraploidMap for Windows, is considerably enhanced, and now goes beyond linkage analysis to perform quantitative trait locus (QTL) interval mapping, with a range of models and thresholds assessed by permutation tests. A Windows-based interface facilitates data entry and exploration. TetraploidMap for Windows is freely available from the Web site of Bioinformatics and Statistics Scotland at http://www.bioss.ac.uk/ (user-friendly software).

We determine the contribution of composite additive, dominance, and epistatic effects to the genetic divergence of photoperiodic response along latitudinal, altitudinal, and longitudinal gradients in the pitcher-plant mosquito, Wyeomyia smithii. Joint scaling tests of crosses between populations showed wide-spread epistasis as well as additive and dominance differences among populations. There were differences due to epistasis between an alpine population in North Carolina and populations in Florida, lowland North Carolina, and Maine. Longitudinal displacement resulted in differences due to epistasis between Florida and Alabama populations separated by 300 km but not between Maine and Wisconsin populations separated by 2000 km. Genetic differences between New Jersey and Ontario did not involve either dominance or epistasis and we estimated the minimum number of effective factors contributing to a difference in mean critical photoperiod of 5 SD between them as nE = 5. We propose that the genetic similarity of populations within a broad northern region is due to their more recent origin since recession of the Laurentide Ice Sheet and that the unique genetic architecture of each population is the result of both mutation and repeated migration-founder-flush episodes during the dispersal of W. smithii in North America. Our results suggest that differences in composite additive and dominance effects arise early in the genetic divergence of populations while differences due to epistasis accumulate after more prolonged isolation.

Heritable variation for resistance to the parasite Lambornella clarki (Corliss & Coats) by its host Aedes sierrensis (Ludlow) and neutral genetic variation among local Oregon mosquito populations were assessed by selection and allozyme frequencies. L. clarki resistance was significantly greater in a population of mosquitoes normally exposed to this parasite than in an unexposed population. Despite this difference between populations, there was no significant increase in heritable resistance to L. clarki within populations of Ae. sierrensis after 1 generation of laboratory selection. Differentiation estimated from allozyme electrophoresis did not coincide with differentiation in L. clarki resistance in Ae. sierrensis populations at the microgeographic scale. Ae. sierrensis has the capacity to respond to foreign clones of the parasite, but electrophoretic surveys may fail to indicate underlying differences in the parasite resistance of mosquito populations.

Density-dependent development in the pitcher plant mosquito, Wyeomyia smithii (Coquillett), indicates variation in competitive ability both within and between populations. We tested 2 disparate populations of W. smithii for 3 types of interference competition: chemical and encounter competition and cannibalism. We found no significant effects of any of these interference mechanisms or variation in food consumption within or between populations. We suggest that asymmetric competition in W. smithii is more likely the result of differences in assimilation or use of assimilated resources than to larval interference or differential ability to consume food.

Lifetime offspring sired by males increases with both male longevity and the rate of female availability. High rates of female availability saturate male ability to sire increasing offspring but do not affect male survivorship. When presented with a saturating number of females in two sequential, 24-h bouts, offspring sired in the second bout is independent of offspring sired in the first bout and is independent of recovery time between bouts. Our results suggest that males will pass up the opportunity to mate and, in so doing, avoid a physiological cost to future reproductive effort or to residual longevity.

Six populations of Wyeomyia smithii from 30—49°N latitude maintain significant heritability for and consistently positive genetic correlations among three components of photoperiodically mediated larval diapause: (1) critical photoperiod, (2) required day number, and (3) depth of diapause. These traits then form genetically coordinated syndrome of traits that reinforce each other in a continuum from diapause-prone to diapause-resistant genotypes. We propose that this syndrome maintains genetic flexibility in a habitat that imposes fluctuating stabilizing selection on diapause.

Cohort fitness and individual female pupal weight in a northern (40°N) U.S. population of Wyeomyia smithii (Coquillett) were inversely proportional to larval density on a fixed resource. Larger females lived longer and realized higher absolute and weight-specific fecundity than did smaller individuals. Females produced a large initial batch of eggs early during their reproductive period and several smaller batches later. Early fecundity was correlated with pupal weight but not longevity. Late fecundity increased with both pupal weight and longevity but there was no significant tradeoff between late and early weight-specific fecundity. Fertility (percent hatch) was higher in earlier than later batches of eggs but there were no significant trade-offs between late fertility and either early fertility or early weight-specific fecundity. Variation in larval density results in reduced weight at pupation which, in turn, results in reduced fecundity and longevity. Consequences of increased larval density thus persist into adulthood as unrealized reproductive potential.

BACKGROUND: BT survivors commonly have impairments in attention/memory that adversely impact independence, home, school and work roles, mood and quality of life. Adults produce new brain cells, replace dead brain cells, and adaptively recruit new brain regions to perform certain tasks. We sought to determine the feasibility, acceptability, and early efficacy signals of an at-home, internet accessible, adaptive, brain-plasticity based computerized intervention designed to enhance attention/memory processes (Plasticity-based Adaptive Cognitive Remediation, PACR). METHODS: Adult BT survivors with self-reported and tested attention/memory impairment, status post surgery and radiation were enrolled (n = 34) into a longitudinal, single-arm study. Patients completed neuropsychological testing before and after intervention. Patients were instructed to complete 40 PACR sessions (1 hour/day, 5 days/week for 8 weeks). A priori feasibility was defined as >80% of patients completing >10 sessions in the first month and not skipping >10 consecutive sessions thereafter. Secondary objectives were to assess improvement on trained tasks (near transfer), unrelated cognitive tests (far transfer), and acceptability. RESULTS: PACR was considered feasible in 40% of patients; 77% reported being "somewhat" or "very satisfied" with PACRs "usefulness in helping to minimize the impact of cognitive symptoms on ability to function effectively in daily activities"; and 100% of subjects would recommend PACR to others. Near transfer of training effects were significant (P < 0.05) on most trained tasks with effect sizes ranging from 0.32 to 1.29. Far transfer of training effects were only seen on the COWA (p = 0.02). CONCLUSIONS: Only 40% of BT survivors completed the PACR intervention as it was prescribed in this study. Near transfer of training but not far transfer of training was observed. Most participants found the intervention useful and all would recommend it to other patients. Consideration of dose-response curves, alternative treatment delivery, and patient selection appears warranted if PACR is to be a viable intervention.

Aedes sierrensis (Ludlow) (Diptera: Culicidae) relies upon photoperiod to initiate a 4th instar diapause at 16.5°C. Short days elicited 100% diapause among larvae from central Oregon and northern California, but thereafter the incidence of diapause declines with latitude so that in southern California only 35% of the sample populations entered diapause. Among that portion of the population capable of responding to day length, the critical photoperiod increased by one h for each 4.8° increase in latitude of origin.

Northern Wyeomyia smithii (Coquillett) (Diptera: Culicidae) are obligatorily autogenous; southern W. smithii , although capable of autogenous development, may consume a blood meal. The clutch of eggs resulting from a blood meal contributes little to capacity for increase. Capacity for increase is inversely correlated with mean crowding of the overwintering population. These results suggest that the principal role of hematophagy in W. smithii relates to increasing the contribution to total reproductive effort made by the 2nd and subsequent ovarian cycles.

Larvae of the carnivorous tree-hole mosquito, Toxorhynchites rutilus septentrionalis (Dyar and Knab), overwinter as diapausing fourth instars from northern Florida to Pennsylvania. When reared in the laboratory at 21 °C after induced mating, larvae from Florida require a longer period for prediapause and pupal development than those from Pennsylvania.

The slope of the line relating dry weight to stage of development does not vary among five species of mosquitoes belonging to all three subfamilies of Culicidae and both tribes within the subfamily Culicinae. Population or community biomass may then be estimated from a general mosquito equation adjusted for the mean weight of a given species' 4th instar.

Final (fourth) larval instars of Chaoborus americanus Johannsen overwinter beneath the ice of Nearctic ponds. These larvae are developmentally dormant but otherwise active; the maintenance and termination of diapause is known to be mediated by photoperiod and the availability of food (Bradshaw 1969). The control of the initiation of diapause has now been examined. It became possible to carry out this study when samples from George Pond on the University of Michigan's E. S. George Reserve yielded numerous early instars of C. americanus on May 1, 1970.