Ecological validity of masking release with speech-like stimuli

Comodulated masking noise and binaural cues can facilitate detecting a target sound from noise. These cues can induce a decrease in detection thresholds, quantified as comodulation masking release (CMR) and binaural masking level difference (BMLD), respectively. However, their relevance to speech perception is unclear as most studies have used artificial stimuli different from speech. Here, we investigated their ecological validity using sounds with speech-like spectro-temporal dynamics. We evaluated the ecological validity of such grouping effect with stimuli reflecting formant changes in speech. We set three masker bands at formant frequencies F1, F2, and F3 based on CV combination: /gu/, /fu/, and /pu/. We found that the CMR was little (< 3 dB) while BMLD was comparable to previous findings (~ 9 dB). In conclusion, we suggest that other features may play a role in facilitating frequency grouping by comodulation such as the spectral proximity and the number of masker bands.

EXPRESS: Temporal grouping effects in verbal and musical short-term memory: Is serial order representation domain-general?

The question of the domain-general versus domain-specific nature of the serial order mechanisms involved in short-term memory is currently under debate. The present study aimed at addressing this question through the study of temporal grouping effects in short-term memory tasks with musical material, a domain which has received little interest so far. The goal was to determine whether positional coding—currently the best account of grouping effect in verbal short-term memory—represents a viable mechanism to explain grouping effects in the musical domain. In a first experiment, non-musicians performed serial reconstruction of 6-tone sequences, where half of the sequences was grouped by groups of three items and the other half presented at a regular pace. The overall data pattern suggests that temporal grouping exerts on tone sequences reconstruction the same effects as in the verbal domain, except for ordering errors which were not characterized by the typical increase of interpositions. This pattern has been replicated in two additional experiments with verbal material, using the same grouping structure as in the musical experiment. The findings support that verbal and musical short-term memory domains are characterized by similar temporal grouping effects for the recall of 6-item lists grouped by three, but it also suggests the existence of boundary condition to observe an increase of interposition errors predicted by positional theories.

PSIX-3 Feedlot performance and rumen morphometrics of Nellore cattle differing in phenotypic residual feed intake

This study, conducted at São Paulo State University feedlot, Dracena campus, Brazil, had the objective to evaluate the effect of ranking Nellore bulls according to residual feed intake (RFI) on feedlot performance and rumen morphometric variables. Twenty-seven 18-mo-old Nellore bulls (425.5 ± 20.1 kg) were randomly allocated in 27 pens (one animal per pen) and fed for 107 days. The multiple step-up diets program consisted of ad libitum feeding of diets with the concentrate level increasing from 70% to 86% concentrate. At harvest, rumen epithelium samples were collected from cranial for rumen morphometric measurements. The RFI was calculated by the difference between the predicted DMI values [DMI = (0.0544*BW0.75) + (2.9659*ADG)] and observed DMI. Then, Nellore bulls were distributed into RFI groups: High (0.5 SD above the mean; n = 8), Medium (±0.5 SD of the mean; n=9) and Low (0.5 SD below the mean; n = 10). Low-RFI Nellore bulls improved (P = 0.04) G:F when compared to High- and Medium-RFI animals (0.142 vs. 0.125 and 0.130; respectively); however, no significant RFI grouping effect was observed for ADG (P = 0.54), final BW (P = 0.54), HCW (P = 0.27), dressing percentage (P = 0.24), final LM area (P = 0.87), final 12th rib fat (P = 0.82), final P8 fat thickness (P = 0.67) and final marbling (P = 0.82). Regarding rumen morphometrics, High-RFI Nellore bulls had larger (P = 0.09) rumen absorptive surface area than Low- and Medium-RFI animals (43.31 vs. 32.95 and 31.27; respectively), which was associated to the greater (P = 0.01) DMI presented by High-RFI animals (10.2 vs. 9.1 and 9.0 for Medium- and Low-RFI Nellore bulls; respectively). Nevertheless, no significant RFI grouping effect was observed for number of papillae (P = 0.28) or mean papillae area (P = 0.61). Thus, Low-RFI Nellore bulls improved feed efficiency without promoting any positive effects on carcass traits and rumen morphometrics.

Elastic Net Regularized Softmax Regression Methods for Multi-subtype Classification in Cancer

<P>Background: Various regularization methods have been proposed to improve the prediction accuracy in cancer diagnosis. Elastic net regularized logistic regression has been widely adopted for cancer classification and gene selection in genetics and molecular biology but is commonly applied to binary classification and regression. However, usually, the cancer subtypes can be more, and most likely cannot be decided precisely. </P><P> Objective: Besides the multi-class issue, the feature selection problem is also a critical problem for cancer subtype classification. </P><P> Methods: An Elastic Net Regularized Softmax Regression (ENRSR) for multi-classification is put forward to tackle the multiple classification issue. As an extension of elastic net regularized logistic regression, ENRSR enforces structure sparsity and ‘grouping effect’ for gene selection based on gene expression data, which may exhibit high correlation. The sparsity structure and ‘grouping effect’ help to select more propriate discriminable features for multi-classification. </P><P> Result: It is demonstrated that ENRSR gains more accurate and robust performance compared to the other 6 competing algorithms (K-means, Hierarchical Clustering, Expectation Maximization, Nonnegative Matrix Factorization, Support Vector Machine and Random Forest) in predicting cancer subtypes both on simulation data and real cancer gene expression data in terms of F measure. </P><P> Conclusion: Our proposed ENRSR method is a reliable regularized softmax regression for multisubtype classification.</P>

Grouping effects in numerosity perception under prolonged viewing conditions

ABSTRACTHumans can estimate numerosities – such as the number sheep in a flock – without deliberate counting. A number of biases have been identified in these estimates, which seem primarily rooted in the spatial organization of objects (grouping, symmetry, etc). Most previous studies on the number sense used static stimuli with extremely brief exposure times. However, outside the laboratory, visual scenes are often dynamic and freely viewed for prolonged durations (e.g., a flock of moving sheep). The purpose of the present study is to examine grouping-induced numerosity biases in stimuli that more closely mimic these conditions. To this end, we designed two experiments with limited-dot-lifetime displays (LDDs), in which each dot is visible for a brief period of time and replaced by a new dot elsewhere after its disappearance. The dynamic nature of LDDs prevents subjects from counting even when they are free-viewing a stimulus under prolonged presentation. Subjects estimated the number of dots in arrays that were presented either as a single group or were segregated into two groups by spatial clustering, dot size, dot color, or dot motion. Grouping by color and motion reduced perceived numerosity compared to viewing them as a single group. Moreover, the grouping effect sizes between these two features were correlated, which suggests that the effects may share a common, feature-invariant mechanism. Finally, we find that dot size and total stimulus area directly affect perceived numerosity, which makes it difficult to draw reliable conclusions about grouping effects induced by spatial clustering and dot size. Our results provide new insights into biases in numerosity estimation and they demonstrate that the use of LDDs is an effective method to study the human number sense under prolonged viewing.

Evaluation of paliperidone on social function in patients with chronic schizophrenia

BackgroundThe impairment of social function is widespread in the patients with chronic schizophrenia, which seriously affects family, life and work conditions.AimsThe main purpose of this study was to investigate the efficacy of paliperidone in the treatment of social function in chronic schizophrenia.MethodsA total of 81 patients who met the standard criteria for schizophrenia and long-term hospitalised inpatients were randomly divided into the treatment group and normal control group following a 1- year prospective follow-up study. The reatment group (41 cases) used paliperidone extended-release tablets for reducing dosage, as appropriate, based on the original treatment strategy; and the control group (40 cases) used the former drugs. All patients were assessed using the Positive and Negative Symptom Scales (PANSS), and the Treatment Emergent Symptom Scale (TESS) was used to assess adverse drug reactions. The Hospitalised Psychiatric Patients’ Social Functions Rating Scale (SSPI) was used to assess social function of participants before and after 8 weeks, 6 months and 1 year of treatment.ResultsAt baseline there were no significant differences between the two groups in age, duration of illness, educational background and dosage of antipsychotic drugs (converted into chlorpromazine equivalency). There was statistically significant difference in PANSS positive symptoms by interaction effect (Fgroup×time=18.24, df=3237, p<0.001) and time effect (Ftime=21.66, df=3, p<0.01) and the difference in PANSS positive symptoms by grouping effect (Fgroup=0.68, df=1, p=0.41) was not statistically significant. The difference of grouping effect of PANSS negative symptoms (Fgroup=9.93, df=1, p=0.002), time effect (Ftime=279.15, df=3, p<0.001) and interaction effect (Fgroup×time=279.15, df=3237, p<0.001) were statistically significant. There were statistically significant differences in the grouping effect (Fgroup=6.59, df=1, p=0.012), time effect (Ftime=152.97, df=3, p<0.001) and interaction effect (Fgroup×time=148.82, df=3237, p<0.001) of PANSS general pathological symptoms, the same as the total score of the PANSS, which showed large differences in grouping effect (Fgroup=7.04, df=1, p=0.001), time effect (Ftime=210.78, df=3, p<0.001) and interaction effect (Fgroup×time=205.20, df=3237, p<0.01). We found in the total SSPI score, grouping effect (Fgroup=31.70, df=1, p<0.001), time effect (Ftime=161.84, df=3, p<0.001) and interaction effect (Fgroup×time=132.74, df=3237, p<0.001) were demonstrated to be significantly different. Even though adverse reactions occurred 7 times in the treatment group and 44 times in the control group based on the Treatment Emergent Symptom Scale (TESS), incidence rate was significantly lower than that of the control group (χ²=18.854, p<0.001).ConclusionPaliperidone can safely and effectively improve negative symptoms and social function in patients with chronic schizophrenia.