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PubMed2001

Cultural perspective on work and family: dual-earner Israeli-Jewish and Arab families at the transition to parenthood.

Parents' functioning in the work and family roles was examined in traditional and modern societies at the transition to parenthood. Participants were 162 dual-earner Israeli-Jewish and Arab families, who were interviewed and observed in dyadic and triadic interactions. Arab parents reported better adaptation to work following the first childbirth, and the triadic family process in Jewish families was more cohesive. Child care arrangements, part-time employment, easier infant temperament, and lower separation anxiety predicted maternal readaptation to work. Traditional sex-role attitudes, career centrality, full-time employment, and marital satisfaction predicted fathers' work adaptation. Parents' family focus, marital satisfaction, and responsive parenting correlated with a cohesive triadic process. Discussion considered the impact of nuclear- and extended-family living arrangements on the emerging work and family roles in young couples.

Adult↗
PubMed2000

Color-luminance relationships and the McCollough effect.

The McCollough effect is an orientation-specific color aftereffect induced by adapting to colored gratings. We examined how the McCollough effect depends on the relationships between color and luminance within the inducing and test gratings and compared the aftereffects to the color changes predicted from selective adaptation to different color-luminance combinations. Our results suggest that the important contingency underlying the McCollough effect is between orientation and color-luminance direction and are consistent with sensitivity changes within mechanisms tuned to specific color-luminance directions. Aftereffects are similar in magnitude for adapting color pairs that differ only in S cone excitation or L and M cone excitation, and they have a similar dependence on spatial frequency. In particular, orientation-specific aftereffects are induced for S cone colors even when the grating frequencies are above the S cone resolution limit. Thus, the McCollough effect persists even when different cone classes encode the orientation and color of the gratings.

Color Perception↗
PubMed2001

Perturbed step initiation in cerebellar subjects: 2. Modification of anticipatory postural adjustments.

Although ataxias of stance and gait are frequent manifestations of cerebellar disease, the number of human studies examining stance or gait in cerebellar subjects is limited. In the present study, we examined whether anticipatory postural adjustments were impaired in cerebellar subjects during perturbed and unperturbed step initiation. The first aim was to show possible abnormalities in timing, force and kinematic parameters of anticipatory postural adjustments in unperturbed stepping in cerebellar subjects. Second, we examined the ability of cerebellar subjects to modify anticipatory postural adjustments associated with step initiation in response to a backward translation. Finally, we asked whether cerebellar subjects (and controls) make use of predictive knowledge of perturbation amplitude in perturbed stepping. Only few abnormalities of anticipatory postural adjustments were found in cerebellar subjects compared to controls. Both in the unperturbed and perturbed step conditions, force production as well as step length and step velocity were reduced in cerebellar subjects compared to controls, suggesting compensatory slowing. Cerebellar subjects also appeared to be less able to use predictive information of perturbation amplitude to scale anticipatory postural adjustments than control subjects. Nevertheless, in unperturbed steps, temporal parameters of anticipatory postural adjustments were preserved in cerebellar subjects. When subjects voluntarily initiated a step in response to the surface translation, both control and cerebellar subjects adapted by executing the anticipatory postural adjustments for step more rapidly. Furthermore, both control and cerebellar subjects were able to use online information regarding perturbation amplitude to scale parameters of step initiation in perturbed stepping. Overall, our findings suggest that the cerebellum is neither critical for the basic motor program underlying unperturbed step initiation nor for many adaptive changes occurring during perturbed step initiation. Like its role in predictive scaling of automatic postural responses to external perturbations, the cerebellum appears to be important for predictive adaptation of anticipatory postural adjustments during step initiation.

Adolescent↗
PubMed2005

Tuning curve shift by attention modulation in cortical neurons: a computational study of its mechanisms.

Physiological studies of visual attention have demonstrated that focusing attention near a visual cortical neuron's receptive field (RF) results in enhanced evoked activity and RF shift. In this work, we explored the mechanisms of attention induced RF shifts in cortical network models that receive an attentional 'spotlight'. Our main results are threefold. First, whereas a 'spotlight' input always produces toward-attention shift of the population activity profile, we found that toward-attention shifts in RFs of single cells requires multiplicative gain modulation. Secondly, in a feedforward two-layer model, focal attentional gain modulation in first-layer neurons induces RF shift in second-layer neurons downstream. In contrast to experimental observations, the feedforward model typically fails to produce RF shifts in second-layer neurons when attention is directed beyond RF boundaries. We then show that an additive spotlight input combined with a recurrent network mechanism can produce the observed RF shift. Inhibitory effects in a surround of the attentional focus accentuate this RF shift and induce RF shrinking. Thirdly, we considered interrelationship between visual selective attention and adaptation. Our analysis predicts that the RF size is enlarged (respectively reduced) by attentional signal directed near a cell's RF center in a recurrent network (resp. in a feedforward network); the opposite is true for visual adaptation. Therefore, a refined estimation of the RF size during attention and after adaptation would provide a probe to differentiate recurrent versus feedforward mechanisms for RF shifts.

Adaptation, Physiological↗
PubMed1980

Further test of a model for loudness coding after adaptation.

The present study attempted to fit Weiler and Hood's (1977) quantitative model for loudness coding to an additional set of simultaneous dichotic loudness balance (SDLB) adaptation data. The error of prediction for test values 10 dB above adapting intensity for 12 normal-hearing listeners was -2.7 to -4.7 dB, an average of -3.5 dB. Since the error of prediction was so nearly constant (S.D. = +/- 737 dB), it seemed reasonable to attribute it do differences in procedural technique, and to conclude that the loudness model does account for coding in the adaptation results.

Dichotic Listening Tests↗
PubMed2025

Harnessing Landscape Genomics to Evaluate Genomic Vulnerability and Future Climate Resilience in an East Asia Perennial.

In this era of rapid climate change, understanding the adaptive potential of organisms is imperative for buffering biodiversity loss. Genomic forecasting provides invaluable insights into population vulnerability and adaptive potential under diverse climatic conditions, thereby facilitating management interventions and bolstering shaping species-specific germplasm conservation strategies. We primarily employed landscape genomics approaches, leveraging single-nucleotide polymorphisms obtained through whole-genome resequencing of 201 individuals across 43 Rheum palmatum complex populations, to pinpoint adaptive variation and its significance in the context of future climates, delineate seed zones, and establish guidelines for ex situ germplasm conservation. The species complex exhibited strong signatures of local adaptation and differential genomic vulnerabilities across its distribution range, with eastern lineage populations facing significant maladaptation risks under future climate scenarios. Using diverse datasets of putatively adaptive loci and climate change scenarios, we delineated three distinct seed zones within the species' range, estimated varying sample sizes per zone to capture most adaptive diversity, and predicted shifts in seed zone centroids ranging from 48.3 to 359.3 km from historical distributions to mitigate climate change impacts. Collectively, our findings underscore the importance of integrating genomic and environmental data to forecast the adaptive trajectory of an East Asian perennial under anticipated climate changes, guide seed zone delineation for germplasm conservation and enhance population resilience. These results provide a blueprint for designing targeted conservation strategies and restoration plans in other imperilled species.

Climate Change↗
PubMed2006

The role of predictive models in the formation of auditory streams.

Sounds provide us with useful information about our environment which complements that provided by other senses, but also poses specific processing problems. How does the auditory system distentangle sounds from different sound sources? And what is it that allows intermittent sound events from the same source to be associated with each other? Here we review findings from a wide range of studies using the auditory streaming paradigm in order to formulate a unified account of the processes underlying auditory perceptual organization. We present new computational modelling results which replicate responses in primary auditory cortex [Fishman, Y.I., Arezzo, J.C., Steinschneider, M., 2004. Auditory stream segregation in monkey auditory cortex: effects of frequency separation, presentation rate, and tone duration. J. Acoust. Soc. Am. 116, 1656-1670; Fishman, Y. I., Reser, D. H., Arezzo, J.C., Steinschneider, M., 2001. Neural correlates of auditory stream segregation in primary auditory cortex of the awake monkey. Hear. Res. 151, 167-187] to tone sequences. We also present the results of a perceptual experiment which confirm the bi-stable nature of auditory streaming, and the proposal that the gradual build-up of streaming may be an artefact of averaging across many subjects [Pressnitzer, D., Hupé, J. M., 2006. Temporal dynamics of auditory and visual bi-stability reveal common principles of perceptual organization. Curr. Biol. 16(13), 1351-1357.]. Finally we argue that in order to account for all of the experimental findings, computational models of auditory stream segregation require four basic processing elements; segregation, predictive modelling, competition and adaptation, and that it is the formation of effective predictive models which allows the system to keep track of different sound sources in a complex auditory environment.

Acoustic Stimulation↗
PubMed2006

Would artificial neural networks implemented in clinical wards help nephrologists in predicting epoetin responsiveness?

BACKGROUND: Due to its strong intra- and inter-individual variability, predicting the ideal erythropoietin dose is a difficult task. The aim of this study was to re-evaluate the impact of the main parameters known to influence the responsiveness to epoetin beta and to test the performance of artificial neural networks (ANNs) in predicting the dose required to reach the haemoglobin target and the monthly dose adjustments. METHODS: We did a secondary analysis of the survey on Anaemia Management in dialysis patients in Switzerland; a prospective, non-randomized observational study, enrolling 340 patients of 26 centres and in order to have additional information about erythropoietin responsiveness, we included a further 92 patients from the Renal Services of the Ente Ospedaliero Cantonale, Bellinzona, Switzerland. The performance of ANNs in predicting the epoetin dose was compared with that of linear regressions and of nephrologists in charge of the patients. RESULTS: For a specificity of 50%, the sensitivity of ANNs compared with linear regressions in predicting the erythropoietin dose to reach the haemoglobin target was 78 vs. 44% (P < 0.001). The ANN built to predict the monthly adaptations in erythropoietin dose, compared with the nephrologists' opinion, allowed to detect 48 vs. 25% (P < 0.05) of the patients treated with an insufficient dose with a specificity of 92 vs. 83% (P < 0.05). CONCLUSION: In predicting the erythropoietin dose required for an individual patient and the monthly dose adjustments ANNs are superior to nephrologists' opinion. Thus, ANN may be a useful and promising tool that could be implemented in clinical wards to help nephrologists in prescribing erythropoietin.

Adolescent↗
PubMed2000

Lay theories of successful aging after the death of a spouse: a network text analysis of bereavement advice.

Social theories of successful aging attempt to explain how individuals adapt to changes characteristically associated with aging and to predict whether older adults' adaptations will lead to successful aging. The death of a spouse and the accompanying bereavement process entail dramatic changes to personal networks and experience to which individuals must adapt to age successfully. Network text analysis (including word frequencies, cluster analysis, and multidimensional scaling) of advice for adjusting to, and coping with, the loss of a spouse given by a sample of 60 bereaved spouses (mean age = 68) at 6 points in time after the death of their marital partner (3-4 weeks to 24 months) reveal respondents' lay theories of successful aging. Thematic clusters address social positioning and qualifiers, activity, communication, time, and spousal characteristics. Results indicate respondents frame their advice as unique to their context of social relationships while providing support for activity theory and negatively addressing disengagement theory.

Aged↗
PubMed1998

[Examination for prediction of residual cholesteatoma].

Residual cholesteatoma, recurrent cholesteatoma, and the open cavity problem still remain to be solved in the surgical treatment of middle ear cholesteatoma. To avoid residual cholesteatoma, complete removal of the cholesteatoma matrix is necessary, but it is sometimes difficult to completely remove it at the initial operation. It is important to estimate the amount of residual cholesteatoma and to completely remove it before its enlargement causes several complications. We established some criteria in order to estimate the residual cholesteatoma at the initial operation, and analyzed the relationship between the criteria and the actual residual cholesteatoma at the second operation. We divided the degree of expectation of residual cholesteatoma into 4 groups: 'none', 'low-rate', 'high-rate', and 'certain'. 'Certain' means that we intentionally left a small part of the matrix to avoid inner ear damage during the procedures. Of 200 cholesteatoma patients who had undergone tympanoplasty between 1985 and 1993, we reviewed 118 who had also undergone a second look or a second stage surgical procedure. Residual cholesteatoma had developed in 25 patients. In those patients, 5 had two pieces of residual cholesteatoma. The incidence of residuum was 0%, 16.5%, 30% and 83.6% in the 'none', 'low-rate', 'high-rate', and 'certain' groups, respectively. The criteria were statistically analyzed and are discussed from the viewpoint of several parameters which would be expected to influence the development of residual cholesteatoma. The analysis disclosed that only one factor influenced the development. The factor was whether the operator could or could not maintain the continuity of the cholesteatoma matrix during the procedure. According to the result, we revised the criterion. The new criterion was considered to be valuable when residual cholesteatoma was predicted, and when adaptation of an exploratory operation was decided.

Adolescent↗
PubMed2005

A population-based study to determine the performance of the Cognitive Adaptive Test/Clinical Linguistic and Auditory Milestone Scale to Predict the Mental Developmental Index at 18 Months on the Bayley Scales of Infant Development-II in very preterm infants.

OBJECTIVES: To determine optimal ages to perform the Cognitive Adaptive Test/Clinical Linguistic and Auditory Milestone Scale (CAT/CLAMS) and optimal "cutoff" score of the CAT/CLAMS to screen very preterm infants (<31 weeks) for severe cognitive-adaptive delay and to ascertain the sensitivity, specificity and likelihood ratios using optimal cutoff scores compared with the Mental Developmental Index (MDI) of the Bayley Scales of Infant Development II. METHODS: A population-based cohort of very preterm infants who were born to mothers who resided in Nova Scotia or Prince Edward Island were evaluated at 4, 8, 12, and 18 months' corrected gestational age, which included a CAT/CLAMS by a physician. At 18 months' corrected gestational age, each child was assessed using the Bayley Scales of Infant Development II, the "gold standard" for developmental delay in young infants. The results of each CAT/CLAMS was compared with the 18-month MDI to identify significant developmental delay (MDI <70). RESULTS: Optimal scores on the CAT/CLAMS to identify correctly MDI <70 were determined by using the kappa statistic for chance independent agreement. Sensitivities and specificities for optimal cutoff scores were as follows: 4-month score <109 (88% and 37%), 8-month score <98 (75% and 82%), 12-month score <81 (63% and 99%), and 18-month score <83 (88% and 98%). CONCLUSION: Sensitivity and specificity of the CAT/CLAMS are high in very preterm infants at identifying major developmental delay at 12 and 18 months. For follow-up programs without psychology services, the CAT/CLAMS at 12 and 18 months is a reasonable screening tool to determine which children need expedited psychology referral for cognitive delay.

Child Development↗
PubMed2002

Increased visual after-effects in migraine following pattern adaptation extend to simultaneous tilt illusion.

Much previous research into visual processing in migraine supports a model of abnormal cortical processing, in between the headache attacks, that is characterised by hyperexcitability, heightened responsiveness, a lack of habituation and/or a lack of intra-cortical inhibition. Shepherd (2001) reported two adaptation studies that challenged this view, one using the tilt after-effect, the second using the motion after-effect. Models of cortical function in migraine based on hyperexcitability and a lack of inhibition lead to specific predictions in an adaptation study: there should have been smaller after-effects in people with migraine than in people without. Both experiments, however, revealed larger after-effects in the migraine group than in the control group. Here, these results are extended to the simultaneous tilt illusion and an identical pattern of results was obtained: there were consistently larger effects in the migraine group than in the control group. The results from the three experiments are not consistent with a lack of inhibition in migraine. The results are discussed in terms of alternative models of cortical function, including a lack of excitation and reduced central energy reserves.

Adaptation, Ocular↗
PubMed1998

Vestibular adaptation: how models can affect data interpretations.

Vestibular adaptation can be induced optically or by chemical or physical injury to the vestibular apparatus or the brain stem. In searching for the sites or mechanisms of vestibular adaptation, neurophysiologists often rely on comparing central resting (background) activities and central modulations (sensitivity) during vestibular stimulation, before and after motor learning or vestibular compensation. It is assumed that adapted central sites must exhibit modulation changes that parallel vestibulo-ocular reflex changes. Using model simulations and analysis, we will show that such presumptions may be misleading. First, using a simple schematic of interconnected cells or nuclei, one can show that modulation depth and background "tone" can be modified (or fixed) independently, using weightings on direct or indirect afferent projections. That is, if synaptic weights along all stimulus pathways are altered, one may fix or strongly modify central premotor characteristics in a manner apparently unrelated to global reflex changes. In the vestibulo-ocular reflex, the dominant premotor pathways contain position-vestibular-pause cells and eye-head-velocity cells (which are behaviorally similar to floccular-target neurons). Several experiments have reported negligible changes in the velocity sensitivity of position-vestibular-pause cells, despite large gain changes in the vestibulo-ocular reflex induced by training with visual-vestibular conflict. On the other hand, the modulation changes on floccular-target neurons (position-vestibular-pause) can be much larger than the changes in reflex gain. Using a bilateral vestibulo-ocular reflex model, we show that overall increases or decreases in reflex gain can be expressed (even overexpressed) in one particular subgroup of premotor neurons. Nevertheless, such observations are theoretically compatible with synaptic changes on all primary projections in a widely interconnected central network. Hence, stable neural responses during reflex adaptation are not sufficient to exclude a potential site of sensory-motor adaptation. Similarly, modified neural responses (as in cerebellum) need not necessarily imply a direct role in supporting the adapted state. Model predictions should help to design additional experimental protocols, to test hypotheses, and to refine diagnostic measures of recovery after vestibular lesions.

Adaptation, Physiological↗
PubMed2004

Gene prediction and verification in a compact genome with numerous small introns.

The genomes of clusters of related eukaryotes are now being sequenced at an increasing rate, creating a need for accurate, low-cost annotation of exon-intron structures. In this paper, we demonstrate that reverse transcription-polymerase chain reaction (RT-PCR) and direct sequencing based on predicted gene structures satisfy this need, at least for single-celled eukaryotes. The TWINSCAN gene prediction algorithm was adapted for the fungal pathogen Cryptococcus neoformans by using a precise model of intron lengths in combination with ungapped alignments between the genome sequences of the two closely related Cryptococcus varieties. This approach resulted in approximately 60% of known genes being predicted exactly right at every coding base and splice site. When previously unannotated TWINSCAN predictions were tested by RT-PCR and direct sequencing, 75% of targets spanning two predicted introns were amplified and produced high-quality sequence. When targets spanning the complete predicted open reading frame were tested, 72% of them amplified and produced high-quality sequence. We conclude that sequencing a small number of expressed sequence tags (ESTs) to provide training data, running TWINSCAN on an entire genome, and then performing RT-PCR and direct sequencing on all of its predictions would be a cost-effective method for obtaining an experimentally verified genome annotation.

Algorithms↗
PubMed2000

CFU-Mk content of immunoselected CD34+ peripheral blood progenitor cells, evaluated with an adapted serum-free methylcellulose assay, is predictive of platelet lineage reconstitution in children with solid tumors.

Immunoselected CD34+ peripheral blood progenitor cell (PBPC) transplantation is now frequently used to support autologous hematopoiesis after myeloablative therapy, its feasability having been proved by several groups. However, we and others observed delayed platelet recovery. We hypothesized that immunoselection processing might induce selective loss of megakaryocyte progenitors, or a decrease in their proliferation. We used a colony-forming units megakaryocyte (CFU-Mk) assay to evaluate these consequences and predict platelet recovery in patients. In CD34+ PBPCs from 10 children with solid tumors, we observed no selective loss in CFU-Mk numbers during immunoselection processing and no impairment of clonogenicity. The CFU-Mk yield (59.2 +/- 11.3%) was at least similar to the CD34+ yield (44.2 +/- 3.8%). We assessed the predictive value of CFU-Mk numbers infused for recovery of platelet lineage. We found an inverse correlation between the time taken to reach a platelet count greater than 50 x 10(9)/L and only the CFU-Mk dose (r = -0.71; p = 0.022) among the different type of progenitors, including colony-forming units granulocyte-macrophage (CFU-GM), burst-forming units erythrocyte (BFU-E) and colony-forming units-mixed (CFU-Mix). These findings suggest that CFU-Mk number could be used as sole predictive functional parameter for platelet reconstitution in children after immunoselection of CD34+ cells, in particular for low CD34+ cell dose, and thus as an indicator for initial quality of hematopoietic cells before in vitro expansion.

Adolescent↗
PubMed2004

Engineering a substrate-specific cold-adapted subtilisin.

One region predicted to be highly flexible for a psychrophilic enzyme, TA39 subtilisin (S39), was transferred in silico to the mesophilic subtilisin, savinase (EC 3.4.21.62), from Bacillus lentus (clausii). The engineered hybrid and savinase were initially investigated by molecular dynamic simulations at 300 K to show binding region and global flexibility. The predicted S39 region consists of 12 residues, which due to homology between the subtilisins, results in a total change of eight residues. By site-directed modifications, the region was transferred to the binding region of savinase, thus a savinase-S39 hybrid, named H5, was constructed. The designed hybrid showed the same temperature optimum and pH profile as savinase, but H5 had higher specific activity on the synthetic substrate N-succinyl-L-Ala-L-Ala-L-Pro-L-Phe-p-nitroanilide (AAPF) at all temperatures measured and, at the same time, H5 showed a decrease in thermostability. The H5 hybrid showed broader substrate specificity, measured at room temperature, due to an increase in catalytic efficiency on AAPF, AAPA and FAAF compared with savinase (N-succinyl-XXXX-pNA; XXXX = AAPF, AAPA and FAAF). The H5 hybrid showed increased activity at low temperature, increased binding region and global flexibility, as investigated by molecular dynamic simulations, and global destabilization from differential scanning calorimetry measurements. These psychrophilic characteristics indicated an increase in binding site flexibility, probably due to the modifications P129S, S130G, P131E, and thus we show that it is possible to increase low temperature activity and global flexibility by engineered flexibility in the binding region.

Bacillus↗
PubMed2002

Heat wave morbidity and mortality, Milwaukee, Wis, 1999 vs 1995: an improved response?

OBJECTIVES: This study examined whether differences in heat alone, as opposed to public health interventions or other factors, accounted for the reduction in heat-related deaths and paramedic emergency medical service (EMS) runs between 1995 and 1999 during 2 heat waves occurring in Milwaukee, Wis. METHODS: Two previously described prediction models were adapted to compare expected and observed heat-related morbidity and mortality in 1999 based on the city's 1995 experience. RESULTS: Both models showed that heat-related deaths and EMS runs in 1999 were at least 49% lower than levels predicted by the 1995 relation between heat and heat-related deaths or EMS runs. CONCLUSIONS: Reductions in heat-related morbidity and mortality in 1999 were not attributable to differences in heat levels alone. Changes in public health preparedness and response may also have contributed to these reductions.

Age Distribution↗