Specific Time Window Research Articles

Sensitivity of Seismic Noise Correlation Functions to Global Noise Sources

AbstractSurface waves in seismic noise correlation functions are routinely exploited for tomographic studies. However, the observation and proper interpretation of body waves is considerably more difficult. To understand body wave generation in particular and the emergence of noise correlation signals in general, we investigate the sensitivity of correlation functions with respect to global noise sources. Treating noise correlation functions as self‐consistent observables, without the enforcement of Green function retrieval, enables us to investigate the quantitative contribution of different noise sources in space to a signal in a specific time window. The source sensitivity kernel for a surface wave reveals the expected dominant and broad region of stationary phase and thereby confirms the robustness of noise tomography in its current state. In contrast, kernels for potential body waves are highly oscillatory and indicate significant contributions from cross terms, for example, from body wave‐surface wave interactions. While the short‐wavelength nature of the body wave kernel may in the future allow us to infer noise sources with great detail, the importance of cross terms combined with the natural heterogeneity of noise sources renders an interpretation of such an arrival as a pure body wave almost impossible. Furthermore, we show that even long‐wavelength Earth structure significantly distorts sensitivity kernels. It is therefore essential to incorporate 3‐D heterogeneities into high‐resolution imaging of ambient noise sources, especially at higher frequencies.

Hijacking Oogenesis Enables Massive Propagation of LINE and Retroviral Transposons

Although animals have evolved multiple mechanisms to suppress transposons, "leaky" mobilizations that cause mutations and diseases still occur. This suggests that transposons employ specific tactics to accomplish robust propagation. By directly tracking mobilization, we show that, during a short and specific time window of oogenesis, retrotransposons achieve massive amplification via a cell-type-specific targeting strategy. Retrotransposons rarely mobilize in undifferentiated germline stem cells. However, as oogenesis proceeds, they utilize supporting nurse cells-which are highly polyploid and eventually undergo apoptosis-as factories to massively manufacture invading products. Moreover, retrotransposons rarely integrate into nurse cells themselves but, instead, via microtubule-mediated transport, they preferentially target the DNA ofthe interconnected oocytes. Blocking microtubule-dependent intercellular transport from nurse cells significantly alleviates damage to the oocyte genome. Our data reveal that parasitic genomic elements can efficiently hijack a host developmental process to propagate robustly, thereby driving evolutionary change and causing disease.

Occupational exposure to high-frequency electromagnetic fields and brain tumor risk in the INTEROCC study: An individualized assessment approach

IntroductionIn 2011, the International Agency for Research on Cancer classified radiofrequency (RF) electromagnetic fields (EMF) as possibly carcinogenic to humans (group 2B), although the epidemiological evidence for the association between occupational exposure to RF-EMF and cancer was judged to be inadequate, due in part to limitations in exposure assessment. This study examines the relation between occupational RF and intermediate frequency (IF) EMF exposure and brain tumor (glioma and meningioma) risk in the INTEROCC multinational population-based case-control study (with nearly 4000 cases and over 5000 controls), using a novel exposure assessment approach. MethodsIndividual indices of cumulative exposure to RF and IF-EMF (overall and in specific exposure time windows) were assigned to study participants using a source-exposure matrix and detailed interview data on work with or nearby EMF sources. Conditional logistic regression was used to investigate associations with glioma and meningioma risk. ResultsOverall, around 10% of study participants were exposed to RF while only 1% were exposed to IF-EMF. There was no clear evidence for a positive association between RF or IF-EMF and the brain tumors studied, with most results showing either no association or odds ratios (ORs) below 1.0. The largest adjusted ORs were obtained for cumulative exposure to RF magnetic fields (as A/m-years) in the highest exposed category (≥90th percentile) for the most recent exposure time window (1–4 years before the diagnosis or reference date) for both glioma, OR = 1.62 (95% confidence interval (CI): 0.86, 3.01) and meningioma (OR = 1.52, 95% CI: 0.65, 3.55). ConclusionDespite the improved exposure assessment approach used in this study, no clear associations were identified. However, the results obtained for recent exposure to RF electric and magnetic fields are suggestive of a potential role in brain tumor promotion/progression and should be further investigated.

Iodine consumption and cognitive performance: Confirmation of adequate consumption.

Iodine, a dynamic nutrient present in thyroid hormones, is responsible for regulating thyroid function, supporting a healthy metabolism, and aiding growth and development. Iodine is also essential for brain development during specific time windows influencing neurogenesis, neuronal and glial cell differentiation, myelination, neuronal migration, and synaptogenesis. About 1.5 billion people in 130 countries live in areas at risk of iron deficiencies (IDs). Reduced mental ability due to IDs occurs in almost 300 million people. Ensuring the consumption of minimum recommended daily allowances of iodine remains challenging. The effects of ID disorders range from high mortality of fetuses and children to inhibited mental development (cretinism). Poor socioeconomic development and impaired school performance are also notable. Currently, ID disorders are the single greatest contributor to preventable brain damage in fetuses and infants and arrested psychomotor development in children. Iodized salt may help fulfill iodine requirements. Increases in food salt iodization programs can help overcome ID disorders. Dietary plans can be well adjusted to incorporate iodinated foods. Maternal iodine supplementation for offspring requires adequate attention. Fruits, vegetables, bread, eggs, legumes (beans and peas), nuts, seeds, seafood, lean meats and poultry, and soy products provide small quantities of iodine. Nutrient‐dense foods containing essential vitamins and minerals such as iodine may confer positive effects. To some extent, fortified foods and daily dietary supplements can be provided for different nutrients including iodine; otherwise, iodine may be consumed in less than the recommended amounts. This review focuses on aspects of adequate iodine consumption to avoid cognitive impairments.

Birth weight variants are associated with variable fetal intrauterine growth from 20 weeks of gestation

Fetal intrauterine growth is influenced by complex interactions between the maternal genes, environment and fetal genes. The aim of this study was to assess the effect of GWAS-identified genetic variants associated with birth weight on intrauterine fetal growth in 665 children. Fetal growth was estimated by two-dimensional ultrasound scans at 20, 25 and 32 weeks of gestation and growth trajectories were modeled using mixed linear regression. A genetic risk score (GRS) of birth weight-raising variants was associated with intrauterine growth showing an attenuating effect on the unconditional daily reduction in proportional weight gain of 8.92 × 10−6 percentage points/allele/day (p = 2.0 × 10−4), corresponding to a mean difference of 410 g at 40 weeks of gestation between a child with lowest and highest GRS. Eight variants were independently associated with intrauterine growth throughout the pregnancy, while four variants were associated with fetal growth in the periods 20–25 or 25–32 weeks of gestation, indicating that some variants may act in specific time windows during pregnancy. Four of the intrauterine growth variants were associated with type 2 diabetes, hypertension or BMI in the UK Biobank, which may provide basis for further understanding of the link between intrauterine growth and later risk of metabolic disease.

Implications of Centers for Medicare & Medicaid Services Severe Sepsis and Septic Shock Early Management Bundle and Initial Lactate Measurement on the Management of Sepsis

Sepsis remains a significant cause of morbidity and mortality in the United States, leading to the implementation of the Severe Sepsis and Septic Shock Early Management Bundle (SEP-1). SEP-1 identifies patients with "severe sepsis" via clinical and laboratory criteria and mandates interventions, including lactate draws and antibiotics, within a specific time window. We sought to characterize the patients affected and to study the implications of SEP-1 on patient care and outcomes. All adults admitted to the University of Chicago from November 2008 to January 2016 were eligible. Modified SEP-1 criteria were used to identify appropriate patients. Time to lactate draw and antibiotic and IV fluid administration were calculated. In-hospital mortality was examined. Lactates were measured within the mandated window 32%of the time on the ward (n= 505) compared with 55%(n= 818) in the ICU and 79%(n= 2,144) in the ED. Patients with delayed lactate measurements demonstrated the highest in-hospital mortality at 29%, with increased time to antibiotic administration (median time, 3.9 vs2.0 h). Patients with initial lactates > 2.0mmol/L demonstrated an increase in the odds of death with hourly delay in lactate measurement (OR, 1.02; 95%CI, 1.0003-1.05; P= .04). Delays in lactate measurement are associated with delayed antibiotics and increased mortality in patients with initial intermediate or elevated lactate levels. Systematic early lactate measurement for all patients with sepsis will lead to a significant increase in lactate draws that may prompt more rapid physician intervention for patients with abnormal initial values.

An Integrated Planning Approach Towards Home Health Care, Telehealth and Patients Group Based Care

The availability of patient-centered, cost effective, and quality oriented health care is a huge task for the health care planners in every country. In this study, a Home Health Care (HHC) planning problem is introduced to integrate the resource dimensioning issues and assignment aspects with the telehealth based care and patients' group-based care services. An integer linear programming model is developed and solved through CPLEX. The main aims of the proposed model are: (i) to provide an optimal selection of locations for HHC offices, health care workers, and patients' cluster centres besides their specific assignment; (ii) to schedule the health care session for each patient or patients' group by creating a pair of HHC nurse and telehealth staff against a specific time window; and (iii) to seek the enhancement of patient satisfaction and quality of service considering the penalties for violation of patients' preferences and inappropriate experience gap between the pair of nurses. Subsequently, in order to validate the effectiveness of the proposed integration approach, we employ the Fuzzy c-means to describe the appropriate organization of the HHC offices, health care workers, and patient's data. Finally, a sensitivity analysis is performed to explore the model behavior against the variation in parameter values. The detailed analysis of the results shows the effectiveness of the proposed model and its behavior with respect to different types of cost.

Optimal diversification strategies in the networks of related products and of related research areas

Countries and cities are likely to enter economic activities that are related to those that are already present in them. Yet, while these path dependencies are universally acknowledged, we lack an understanding of the diversification strategies that can optimally balance the development of related and unrelated activities. Here, we develop algorithms to identify the activities that are optimal to target at each time step. We find that the strategies that minimize the total time needed to diversify an economy target highly connected activities during a narrow and specific time window. We compare the strategies suggested by our model with the strategies followed by countries in the diversification of their exports and research activities, finding that countries follow strategies that are close to the ones suggested by the model. These findings add to our understanding of economic diversification and also to our general understanding of diffusion in networks.

Pharmacologically induced amnesia for learned fear is time and sleep\xa0dependent

The discovery in animal research that fear memories may change upon retrieval has sparked a wave of interest into whether this phenomenon of reconsolidation also occurs in humans. The critical conditions under which memory reconsolidation can be observed and targeted in humans, however, remain elusive. Here we report that blocking beta-adrenergic receptors in the brain, either before or after reactivation, effectively neutralizes the expression of fear memory. We show a specific time-window during which beta-adrenergic receptors are involved in the reconsolidation of fear memory. Finally, we observe intact fear memory expression 12 h after reactivation and amnesic drug intake when the retention test takes place during the same day as the intervention, but post-reactivation amnesia after a night of sleep (12 h or 24 h later). We conclude that memory reconsolidation is not simply time-dependent, but that sleep is a final and necessary link to fundamentally change the fear memory engram.

Monitoring of kidney injury in preterm infants

Acute kidney injury (AKI) is a common complication in the neonatal intensive care unit that causes a high mortality of preterm infants and various chronic kidney diseases in adulthood. Preterm infants have immature development of the kidneys at birth. The kidneys continue to develop within a specific time window after birth. However, due to various factors during pregnancy and after birth, preterm infants tend to develop AKI. At present, serum creatinine and urine volume are used for the assessment of kidney injury, and their early sensitivity and specificity have attracted increasing attention. In recent years, various new biomarkers have been identified for early recognition of AKI. This article reviews the features, risk factors, renal function assessment, and prevention/treatment of AKI of preterm infants, in order to provide a reference for improving early diagnosis and treatment of AKI in preterm infants and long-term quality of life.

Temporal profiling of an acute stress-induced behavioral phenotype in mice and role of hippocampal DRR1

Understanding the neurobiological mechanisms underlying the response to an acute stressor may provide novel insights into successful stress-coping strategies. Acute behavioral stress-effects may be restricted to a specific time window early after stress-induction. However, existing behavioral test batteries typically span multiple days or even weeks, limiting the feasibility for a broad behavioral analysis following acute stress. Here, we designed a novel comprehensive behavioral test battery in male mice that assesses multiple behavioral dimensions within a sufficiently brief time window to capture acute stress-effects and its temporal profile. Using this battery, we investigated the behavioral impact of acute social defeat stress (ASD) early thereafter (ASD-early, ∼4 h), when circulating corticosterone levels were elevated, and late after stress-induction (ASD-late, ∼8 h), when corticosterone were returned to timed control levels. ASD-early, but not ASD-late, displayed hippocampal-dependent cognitive impairments in the Y-maze and in the spatial object recognition test. The actin-binding protein (ABP) Tumor suppressor down-regulated in renal cell carcinoma 1 (DRR1) has been described as resilience-promoting factor but the potential of DRR1 to curb stress-effects has not been investigated. Hippocampal DRR1 mRNA-expression was increased in ASD-early and ASD-late whereas DRR1-protein levels were increased only in ASD-late. We hypothesized that the absence of hippocampal DRR1 protein-upregulation in ASD-early caused the associated cognitive impairments. Hence, virus-mediated hippocampal DRR1-overexpression was induced as putative treatment, but cognitive deficits in ASD-early were not improved. We conclude that hippocampal DRR1-overexpression is insufficient to protect from the detrimental cognitive effects following acute social stress where perhaps a more global response in local actin dynamics, involving multiple stress-responsive ABPs that act synergistically, was warranted.

A customizable artificial auditory fovea

Neuroscience shows that auditory neurons extract a variety of specific signal parameters such as frequency, amplitude modulation, frequency modulation, and onsets. Furthermore, biology gives us examples of auditory foveae in bats and owls where there is overrepresentation of behaviorally relevant signal parameters. This shows that biology finds nuances of these parameters to be more important than compact coding considerations such as orthonormal basis functions. In contrast to typical spectrogram approaches where a specific time window is chosen and where the Fast Fourier Transform provides non-overlapping orthogonal rectangular tilings, we start with the smallest tiling possible. The uncertainty principle gives us this tiling as the Gaussian modulated sinusoid. We can rotate this tiling in the time-frequency plane, which gives us a chirplet. We then construct many chirplets (a chirplet set) centered at the same time-frequency point. We then find the chirplet that best matches the signal at this point. Our ability to sample at arbitrary locations in the time-frequency plane with different chirplet sets gives us the ability to create customizable artificial auditory foveae. We use this chirplet front-end for a classification task of identifying Marmoset vocalizations and comparisons to typical spectrogram methods for audio classification are made.

P.1.008 - Differential role of phosphodiesterase inhibitors on AMPA receptor trafficking and downstream cyclic nucleotide signaling

Previous studies have shown that the cGMP-selective PDE5 inhibitor, vardenafil, and the cAMP-selective PDE4 inhibitor, rolipram, could improve synaptic plasticity when they are applied in specific time windows [1,2]. Subsequently it is proposed that the distinction of long-term potentiation (LTP) into early and late phase relies on distinguish molecular cascades activating the cGMP/protein kinase G (PKG) and cAMP/protein kinase A (PKA), respectively. In the present study we aim to shed light into the mechanism that underlies the role of the above cascades in synaptic enhancement. A major player of mediating the effects of nucleotide signaling on synaptic plasticity is the glutamatergic AMPA receptor (AMPAR). Additionally, it was shown that phosphorylation of AMPARs at the S845 site by PKA and PKG promotes their trafficking into the membrane. Therefore, we hypothesize that the differential effect of the above inhibitors could be mediated by an increase in AMPAR synthesis and trafficking into the membrane. In order to examine the above hypothesis we incubate mouse hippocampal slices either with vardenafil or rolipram in 3 different times points during a chemical LTP (cLTP) induction protocol; 10 min before, 10 min after and 60 min after cLTP for targeting the acquisition-like, the early phase and the late phase of synaptic plasticity, respectively. Subsequently, membrane and total fractions of the GluR1 subunit of the AMPAR were assessed via separation of surface biotin-labeled proteins from the cytosolic unlabeled proteins using streptavidin magnetic beads. Our findings demonstrate that incubation of both PDE inhibitors 10 min before cLTP upregulates the number of AMPAR in the membrane without affecting the total number of the receptors. Considering that this upregulation is accompanied with increased AMPAR phosphorylation, a pre-requisite of its insertion in the membrane, we show that perfusion with both inhibitors before cLTP promotes the trafficking of an already existing pool of AMPAR without affecting the total number of the receptors. Interestingly, incubation with each of the inhibitors after induction of cLTP has a distinguishing effect. Specifically, vardenafil increases AMPAR synthesis and trafficking only when it is given 10 min, but not 60 min after induction of cLTP. On the contrary, application of rolipram has an opposite outcome, since it increases AMPAR synthesis and trafficking only when it is given at the late, but not at the early phase of cLTP. In both cases, the observed upregulation in AMPAR phosphorylation is due to increased total levels, indicating that the elevated AMPAR in the membrane fraction is mainly due to production of new receptors that subsequently travel to the membrane. Concluding, our study is the first to show that the distinctive role of the above PDE inhibitors and their downstream nucleotide signaling in improving plasticity is due to underlying cascades that promote AMPAR synthesis and subsequently insertion into the membrane.

Excited-state dissociation dynamics of phenol studied by a new time-resolved technique

Phenol is an important model molecule for the theoretical and experimental investigation of dissociation in the multistate potential energy surfaces. Recent theoretical calculations [X. Xu et al., J. Am. Chem. Soc. 136, 16378 (2014)] suggest that the phenoxyl radical produced in both the X and A states from the O-H bond fission in phenol can contribute substantially to the slow component of photofragment translational energy distribution. However, current experimental techniques struggle to separate the contributions from different dissociation pathways. A new type of time-resolved pump-probe experiment is described that enables the selection of the products generated from a specific time window after molecules are excited by a pump laser pulse and can quantitatively characterize the translational energy distribution and branching ratio of each dissociation pathway. This method modifies conventional photofragment translational spectroscopy by reducing the acceptance angles of the detection region and changing the interaction region of the pump laser beam and the molecular beam along the molecular beam axis. The translational energy distributions and branching ratios of the phenoxyl radicals produced in the X, A, and B states from the photodissociation of phenol at 213 and 193 nm are reported. Unlike other techniques, this method has no interference from the undissociated hot molecules. It can ultimately become a standard pump-probe technique for the study of large molecule photodissociation in multistates.

Asian Hydroclimate Changes and Mechanisms in the Preboreal from an Annually‐laminated Stalagmite, Daoguan Cave, Southern China

AbstractOne‐year‐resolved and annually‐counted stalagmite multi‐proxies (δ18O, δ13C, and layer width) from Daoguan Cave, Guizhou Province revealed detailed variability regarding the Asian Summer Monsoon (ASM) and local humidity across Bond events (BE) in the Preboreal. During BEs 8 and 7, 1.5± enrichments in δ18O values were generally consistent with high‐ to low‐latitude climate changes. In detail, the decadal‐scale minor δ18O oscillations in BE8 were broadly less than the mean value, in contrast to the significant changes in local soil moisture derived from the δ13C values and layer records. In the mid‐BE7, δ18O variability was generally above the average level, and higher‐ amplitude variations were observed in the three proxy indicators. Wavelet analysis on the total δ18O time series and across the specific time windows of BEs 8 and 7 identified periodicities of about 130, 60, and 20‐a, respectively. Exceptionally strong in BE7, the 60‐a cycle, pervasively observed in instrumental studies, became prominent starting at 11.4 kaBP. Thus, glacial background conditions are important for suppressing the ASM intensity in BE8, while during BE7, tropical hydrological circulations were potentially actively involved. Consequently, climate internal oscillations, analogous to modern conditions, might have occurred in the distant past once the link between the tropical ocean and atmosphere was established as occurs today.

The surprising subtleties of changing fear memory: a challenge for translational science.

Current pharmacological and psychological treatments for disorders of emotional memory only dampen the affective response while leaving the original fear memory intact. Under adverse circumstances, these original memories regain prominence, causing relapses in many patients. The (re)discovery in neuroscience that after reactivation consolidated fear memories may return to a transient labile state, requiring a process of restabilization in order to persist, offers a window of opportunity for modifying fear memories with amnestic agents. This process, known as memory reconsolidation, opens avenues for developing a revolutionary treatment for emotional memory disorders. The reconsolidation intervention challenges the dominant pharmacological and psychological models of treatment: it is only effective when the amnestic drug is given in conjunction with memory reactivation during a specific time window, and a modification of cognitive processes is a boundary condition for changing fear. Notwithstanding the dramatic effects of targeting memory reconsolidation in the laboratory (i.e. proof of principle), the greatest hurdle to overcome is that the success of the manipulation depends on subtle differences in the reactivation procedure. These experimental parameters cannot be easily controlled in clinical practice. In harnessing the clinical potential of memory reconsolidation, a heuristic for bi-directionally translating behavioural neuroscience and clinical science is proposed.This article is part of a discussion meeting issue ‘Of mice and mental health: facilitating dialogue between basic and clinical neuroscientists’.

Architectural concepts for managing biomedical sensor data utilised for medical diagnosis and patient remote care.

This paper discusses experiences and architectural concepts developed and tested aimed at acquisition and processing of biomedical data in large scale system for elderly (patients) monitoring. Major assumptions for the research included utilisation of wearable and mobile technologies, supporting maximum number of inertial and biomedical data to support decision algorithms. Although medical diagnostics and decision algorithms have not been the main aim of the research, this preliminary phase was crucial to test capabilities of existing off-the-shelf technologies and functional responsibilities of system’s logic components. Architecture variants contained several schemes for data processing moving the responsibility for signal feature extraction, data classification and pattern recognition from wearable to mobile up to server facilities. Analysis of transmission and processing delays provided architecture variants pros and cons but most of all knowledge about applicability in medical, military and fitness domains. To evaluate and construct architecture, a set of alternative technology stacks and quantitative measures has been defined. The major architecture characteristics (high availability, scalability, reliability) have been defined imposing asynchronous processing of sensor data, efficient data representation, iterative reporting, event-driven processing, restricting pulling operations. Sensor data processing persist the original data on handhelds but is mainly aimed at extracting chosen set of signal features calculated for specific time windows – varying for analysed signals and the sensor data acquisition rates. Long term monitoring of patients requires also development of mechanisms, which probe the patient and in case of detecting anomalies or drastic characteristic changes tune the data acquisition process. This paper describes experiences connected with design of scalable decision support tool and evaluation techniques for architectural concepts implemented within the mobile and server software.

Performance Assessment of Tailored Split-Window Coefficients for the Retrieval of Lake Surface Water Temperature from AVHRR Satellite Data

Although lake surface water temperature (LSWT) is defined as an essential climate variable (ECV) within the global climate observing system (GCOS), current satellite-based retrieval techniques do not fulfill the GCOS accuracy requirements. The split-window (SW) retrieval method is well-established, and the split-window coefficients (SWC) are the key elements of its accuracy. Performances of SW depends on the degree of SWC customization with respect to its application, where accuracy increases when SWC is tailored for specific situations. In the literature, different SWC customization approaches have been investigated, however, no direct comparisons have been conducted among them. This paper presents the results of a sensitivity analysis to address this gap. We show that the performance of SWC is most sensitive to customizations for specific time-windows (Sensitivity Index SI of 0.85) or spatial extents (SI 0.27). Surprisingly, the study highlights that the use of separated SWC for daytime and night-time situations has limited impact (SI 0.10). The final validation with AVHRR satellite data showed that the subtle differences among different SWC customizations were not traceable to the final uncertainty of the LSWT product. Nevertheless, this study provides a basis to critically evaluate current assumptions regarding SWC generation by directly comparing the performance of multiple customization approaches for the first time.

Land degradation affects shrub growth responses to precipitation in a semiarid rangeland of north‐eastern Patagonia (Argentina)

AbstractArid land degradation diminishes the proportion of precipitation conducted to infiltration and increases the proportion lost to run‐off and evaporation. Consequently, we expect that the effects of annual precipitation on shrub growth vary with land degradation as a result of changes in soil available water. Chuquiraga avellanedae is the dominant shrub and the main indicator of land degradation in semiarid rangelands of north‐eastern Patagonia. We chose two communities with a different degree of land degradation: an herbaceous steppe with shrubs (HSS) and a degraded shrub steppe (SS). Vegetative growth of C. avellanedae was determined nondestructively using a double‐sampling approach. Soil water content was estimated for the two communities using a soil water balance model. Linear regressions were used to evaluate the relationships between shrub growth and (i) annual precipitation and (ii) mean available water during the period of high vegetative growth in the soil layer that each plant community concentrates their roots. In SS, with elevated clay content, there were more roots of C. avellanedae in the upper layers of soil while in HSS, with coarse‐textured soil, C. avellanedae had more roots in deeper layers. Vegetative growth of C. avellanedae, both in HSS and SS communities, was positively related to annual precipitation but, for a given precipitation, C. avellanedae presented higher vegetative growth in HSS than in SS. We also found a positive relationship between vegetative growth and soil available water, and this relationship did not differ between communities. SS presented lower water availability because of lower infiltration rates. Our results showed that, irrespective of the degree of land degradation, plants respond directly to water content of the soil layers where most roots are present at a specific window of time.

Delta-gamma coupling as a potential neurophysiological mechanism of fluid intelligence

Electrophysiological investigations have pointed out significant yet weak correlations between intelligence and oscillatory brain activity, including the spectral power, frequency, complexity, synchrony, and coherence of electroencephalographic (EEG) signals, however neglecting the interplay between fast and slow neuronal oscillations underlying information transfer in the brain. We found that fluid intelligence level (gf) depends on the precise synchronization of fast oscillations to a specific time window of slow brain rhythms. Specifically, by examining EEG recordings of 50 people in resting state as well as during performance at two gf tasks we found converging evidence that high-gf participants display stronger Phase-Amplitude Coupling (PAC) related to an increased concentration of gamma (~36Hz) spectral power at the descending phase of delta oscillations (~3Hz). Delta-gamma PAC strength explained 35% variance in scores on multiple gf tests, outperforming six alternative EEG-based predictors including spectral power, complexity and amplitude-amplitude coupling. Present results suggest PAC as a neurophysiological substrate of gf in humans, offering novel insight about the role of slow and fast brain rhytms in high-order cognition, as well as a potential new target for neuromodulatory interventions in the healthy and pathological brain.