Visuomotor adaptation modulates the clustering of sleep spindles into trains

Sleep spindles are thought to promote memory consolidation. Recently, we have shown that visuomotor adaptation (VMA) learning increases the density of spindles and promotes the coupling between spindles and slow oscillations, locally, with the level of spindle-SO synchrony predicting overnight memory retention. Yet, growing evidence suggests that the rhythmicity in spindle occurrence may also influence the stabilization of declarative and procedural memories. Here, we examined if VMA learning promotes the temporal organization of sleep spindles into trains. We found that VMA increased the proportion of spindles and spindle-SO couplings in trains. In agreement with our previous work, this modulation was observed over the contralateral hemisphere to the trained hand, and predicted overnight memory retention. Interestingly, spindles grouped in a cluster showed greater amplitude and duration than isolated spindles. The fact that these features increased as a function of train length, provides evidence supporting a biological advantage of this temporal arrangement. Our work opens the possibility that the periodicity of NREM oscillations may be relevant in the stabilization of procedural memories.

The Human Female Paradox: Biological Disadvantage Preimplantation, Biological Advantage, Thereafter

The vital statistics show that human females outlive males at every biological stage. Once the embryo arrives in the uterus, more males die at every stage, at least until the eighth decade when the majority of survivors are female. Unexpectedly, the same statistics also show that more boys are born than girls, which is difficult to explain, because the sperm that determine the sex of the fetus, are not skewed toward males. Recently, new data reveal the reason for the increased number of male births; they imply the significant loss of females before the fetus arrives in the womb. Thereafter, there is an excessive loss of males – not only in utero but throughout their lives. One likely reason for the sex differences in fetal survival is the way that humans compensate for the sex difference in number of X chromosomes.

Mirrored brain organization: Statistical anomaly or reversal of hemispheric functional segregation bias?

Humans demonstrate a prototypical hemispheric functional segregation pattern, with language and praxis lateralizing to the left hemisphere and spatial attention, face recognition, and emotional prosody to the right hemisphere. In this study, we used fMRI to determine laterality for all five functions in each participant. Crucially, we recruited a sample of left-handers preselected for atypical (right) language dominance (n= 24), which allowed us to characterize hemispheric asymmetry of the other functions and compare their functional segregation pattern with that of left-handers showing typical language dominance (n= 39). Our results revealed that most participants with left language dominance display the prototypical pattern of functional hemispheric segregation (44%) or deviate from this pattern in only one function (35%). Similarly, the vast majority of right language dominant participants demonstrated a completely mirrored brain organization (50%) or a reversal for all but one cognitive function (32%). Participants deviating by more than one function from the standard segregation pattern showed poorer cognitive performance, in line with an oft-presumed biological advantage of hemispheric functional segregation.

Comparative assessment of storage stability of ginger-garlic and chemical preservation on fruit juice blends

The study aimed at reduction of wastage of fruit, encourage production, consumption and preservation of fruit juice blends using garlic ginger filtrate with health benefits as biopreservative thus providing alternatives with biological advantage over chemical preservatives (ascorbic and benzoate acids) without altering the organoleptic and physicochemical properties of fruit juice blends. The study evaluated the potential of natural preservatives (ginger, garlic and ginger-garlic filtrates) in comparison with two conventional chemical preservatives (ascorbic and benzoate acids) for fruit juice blends preservation. The juice blend used was cashew, pineapple and watermelon. In terms of flavor and mouth feel, the order of preference of the juice were the preserved with 1% garlic-ginger > 1% ginger > 1% garlic > 1% ascorbic acid > and preserved with 1% sodium benzoate at ambient temperature. Maximum decrease in pH was observed in the juice sample that had no added preservative. Generally, all the fruit blends (preserved and unpreserved), with the exception of the one preserve with 1% ginger-garlic showed growth of bacteria after one week of storage. Juice blends preserved with the 1% ginger-garlic were most acceptable compared to other preservatives. The synergistic biopreservative ability observed with the ginger-garlic may be a preferable alternative to conventional preservatives.

Morpho-experimental substantiation of application of electroplating dentures for patients with missing teeth and periodontitis

The choice of material for the manufacture of prostheses in patients with inflammatory periodontal diseases is of particular relevance. When using plates from cobalt-chromium alloy with electroplating destructive changes in the tissues are less pronounced. In response to damage, aseptic serous inflammation develops. Granulation tissue is formed in the wound, healing occurs by primary tension and in a shorter time. The results of the study allow to predict that the use of electroplating will significantly improve the clinical efficiency of the use of clasp prostheses in patients with periodontal disease, as the gold-containing coating has the properties of bioinert, has a clinical and biological advantage in predicting the long-term results of orthopedic treatment.

Vocal similarity predicts the relative attraction of musical chords

Musical chords are combinations of two or more tones played together. While many different chords are used in music, some are heard as more attractive (consonant) than others. We have previously suggested that, for reasons of biological advantage, human tonal preferences can be understood in terms of the spectral similarity of tone combinations to harmonic human vocalizations. Using the chromatic scale, we tested this theory further by assessing the perceived consonance of all possible dyads, triads, and tetrads within a single octave. Our results show that the consonance of chords is predicted by their relative similarity to voiced speech sounds. These observations support the hypothesis that the relative attraction of musical tone combinations is due, at least in part, to the biological advantages that accrue from recognizing and responding to conspecific vocal stimuli.

SEX COMPOSITION OF TWINS AND ASSOCIATIONS WITH MORBIDITY, MORTALITY AND MATERNAL TREATMENT-SEEKING OUTCOMES IN RESOURCE-POOR SETTINGS

SummarySocietal gender inequality and a preference for male children has been shown to be detrimental to girls’ health. This is despite females’ innate biological advantage early in life. The negative effects of gender inequity on female health are most pronounced in resource-poor countries, where cultural norms supporting a preference for male children are strongest. However, most of what is known about gender inequality and child health comes from studies of singleton births. There is little evidence for how, or if, the disadvantages associated with gender bias and son preference extend to multiple births, a population inherently at risk for a number of health challenges. This analysis examines whether gender bias in health outcomes exists for twins. Data on live twin births from 38 Demographic and Health Surveys were compiled (n=11,528 individuals) and twins were categorized as girl/girl, girl/boy, boy/girl or girl/girl. Gender inequality was measured via the Gender Inequality Index. Multilevel logistic regression models examined associations between twin sex composition, gender inequality and eight outcomes of infant and child morbidity, mortality and mother’s treatment-seeking behaviours. Twin pairs containing girls had significantly lower odds of first-year mortality. Higher country-level gender inequality was associated with higher odds of reporting diarrhoea and fever/cough, as well as an increased odds of post-neonatal mortality. Results suggest that the biological advantage for females may be stronger than son preference and gender inequality in the first year of life. Understanding these relationships has the potential to inform efforts to curb the influence of gender preference on the health of female children in resource-poor settings.

NF-κB oscillations translate into functionally related patterns of gene expression

Several transcription factors (TFs) oscillate, periodically relocating between the cytoplasm and the nucleus. NF-κB, which plays key roles in inflammation and cancer, displays oscillations whose biological advantage remains unclear. Recent work indicated that NF-κB displays sustained oscillations that can be entrained, that is, reach a persistent synchronized state through small periodic perturbations. We show here that for our GFP-p65 knock-in cells NF-κB behaves as a damped oscillator able to synchronize to a variety of periodic external perturbations with no memory. We imposed synchronous dynamics to prove that transcription of NF-κB-controlled genes also oscillates, but mature transcript levels follow three distinct patterns. Two sets of transcripts accumulate fast or slowly, respectively. Another set, comprising chemokine and chemokine receptor mRNAs, oscillates and resets at each new stimulus, with no memory of the past. We propose that TF oscillatory dynamics is a means of segmenting time to provide renewing opportunity windows for decision.