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How humans and animals segregate sensory information into discrete, behaviorally meaningful categories is one of the hallmark questions in neuroscience. Much of the research around this topic in the auditory system has centered around human speech perception, in which categorical processes result in an enhanced sensitivity for acoustically meaningful differences and a reduced sensitivity for nonmeaningful distinctions. Much less is known about whether nonhuman primates process their species-specific vocalizations in a similar manner. We address this question in the common marmoset, a small arboreal New World primate with a rich vocal repertoire produced across a range of behavioral contexts. We first show that marmosets perceptually categorize their vocalizations in ways that correspond to previously defined call types for this species. Next, we show that marmosets are differentially sensitive to changes in particular acoustic features of their most common call types and that these sensitivity differences are matched to the population statistics of their vocalizations in ways that likely maximize category formation. Finally, we show that marmosets are less sensitive to changes in these acoustic features when within the natural range of variability of their calls, which possibly reflects perceptual specializations which maintain existing call categories. These findings suggest specializations for categorical vocal perception in a New World primate species and pave the way for future studies examining their underlying neural mechanisms. [ABSTRACT FROM AUTHOR]

The Hold-up problem is very common in transactions with specific investment in incomplete contractual relationships, which is affected by human trusting, cooperative, altruistic behavior. Recent neuroscience studies have shown that TPJ plays an important role in social cognition and prosocial decision-making. However, most of the studies have focused on RTPJ in the right hemisphere, while few studies have focused on LTPJ in the left hemisphere. The purpose of this study is to modulate the excitability of LTPJ through transcranial direct current stimulation (tDCS) and to explore the effects of LTPJ on the investment and offer behavior of participants in the repeated hold-up game. Our results showed that cathodal stimulation significantly improved the investment rate of participants in the repeated hold-up game compared with sham stimulation. One possible explanation is that the change of LTPJ activity caused by cathodal stimulation may reduce the participants' inference ability of the others' intention, thus reducing the participants' betrayal aversion behavior, so that the participants will not reduce their investment behavior in the repeated game. • The LTPJ is the brain region related to social reasoning. • Cathodal tDCS over LTPJ increased the degree of trust. • The LTPJ is involved in ability to trust and infer others' intention. [ABSTRACT FROM AUTHOR]

• The rTPJ is the cooperative brain region. • Anodal tDCS over rTPJ increased the degree of cooperation. • The rTPJ is involved in pure cooperative motives. Hold-up problem is very common in non-contractible relation-specific investment transactions. And this problem can affect by trust, cooperation and altruism behavior of human beings. Recent neuroscience researches had explored a network of right temporo-parietal junction (rTPJ) involved in human cooperation and altruism behavior. The purpose of this study is to modulate the activation of rTPJ through transcranial direct current stimulation (tDCS), and to study the influence of rTPJ on investment and offer behavior in hold-up game. The results of our study showed that the anodal stimulation significantly increased participants' offer compared with the cathodal and sham stimulation. A possible explanation is that changes in rTPJ activity induced by anodal stimulation improve the accuracy of agents' mental reasoning and promote cooperation by influencing agents' offer behavior. [ABSTRACT FROM AUTHOR]

• In contests, overbidding is widespread. • Group identity can alleviate overbidding. • Frontal lobes activated pre-group identity task, increased right temporal lobe activation post-task. • Functional connectivity in social brain regions changes before and after the group identity task. Contests may be highly effective in eliciting high levels of effort, but they also carry the risk of inefficient resource allocation due to excessive effort (overbidding), squandering valuable social resources. While a growing body of research has focused on how group identity exacerbates out-group conflict, its influence on in-group conflict remains relatively unexplored. This study endeavors to explore the impact of group identity on conflicts within and between groups in competitive environments, thereby addressing gaps in the current research landscape and dissecting the involved neurobiological mechanisms. By employing source localization and functional connectivity techniques, our research aims to identify the brain regions involved in competitive decision-making and group identity processes, as well as the functional connectivities between social brain areas. The results of our investigation revealed that participants exhibited activation in the bilateral frontal and prefrontal lobes during the bidding behavior before the group identity task. Subsequently, after the task, additional activation was observed in the right temporal lobe. Results from functional connectivity studies indicated that group identity tasks modify decision-making processes by promoting group norms, empathy, and blurred self-other boundaries for in-group decisions, while out-group decisions after the group identity task see heightened cognitive control, an increased dependence on rational judgment, introspection of self-environment relationships, and a greater focus on anticipating others' behaviors. This study reveals the widespread occurrence of overbidding behavior and demonstrates the role of group identity in mitigating this phenomenon, concurrently providing a comprehensive analysis of the underlying neural mechanisms. [ABSTRACT FROM AUTHOR]

Like other organisms, plants have endogenous biological clocks that enable them to organize their metabolic, physiological, and developmental processes. The representative biological clock is the circadian system that regulates daily (24-h) rhythms. Circadian-regulated changes in growth have been observed in numerous plants. Evidence from many recent studies indicates that the circadian clock regulates a multitude of factors that affect plant metabolites, especially emitted volatiles that have important ecological functions. Here, we review recent progress in research on plant volatiles showing rhythmic emission under the regulation of the circadian clock, and on how the circadian clock controls the rhythmic emission of plant volatiles. We also discuss the potential impact of other factors on the circadian rhythmic emission of plant volatiles. [ABSTRACT FROM AUTHOR]

Deep eutectic solvents (DES) were formed from choline chloride (ChCl). DES-modified polymer monolithic (DES-M), template molecular polymer monolithic and non-DES-M without a molecular template were synthesized in identical process. These polymer materials were characterized by field emission scanning electron microscopy and Fourier transform infrared spectroscopy. The significant selective adsorption properties of the polymers were assessed by an absorption capacity experiment and solid-phase extraction (SPE). The optimized extraction procedure was as follows: ultrasonic time (30min), optimal solvent (ethanol) and liquid to material ratio (20mLg-1). Under this condition, the amount of quercetin extracted from Ginkgo biloba was 290.8mg g-1. The purification of G. biloba was achieved by the SPE process. Based on the results, DESs-based monolithic cartridges can be used for simple and efficient extraction and as a pre-concentration technique for the purification of bioactive compounds or drugs in aqueous environments with high affinity and selectivity. [ABSTRACT FROM AUTHOR]

Different kinds of deep eutectic solvents (DES) based on choline chloride (ChCl) and ionic liquids (ILs) based on 1-methylimidazole were used to modify Fe3O4/molecularly imprinted polymers (Fe3O4/MIPs), and the resulting materials were applied for the rapid purification of alkaloid isomers (theobromine and theophylline) from green tea with magnetic solid-phase extraction (M-SPE). The M-SPE procedure was optimized using the response surface methodology (RSM) to analyze the maximum conditions. The materials were characterized by Fourier transform infrared spectroscopy (FI-IR) and field emission scanning electron microscopy (FE-SEM). Compared to the ILs-Fe3O4/MIPs, the DESs-Fe3O4/MIPs were developed for the stronger recognition and higher recoveries of the isomers (theophylline and theobromine) from green tea, particularly DES-7-Fe3O4/MIPs. With RSM, the optimal recovery condition for theobromine and theophylline in the M-SPE were observed with ratio of methanol (80%) as the washing solution, methanol/acetic acid (HAc) (8:2) as the eluent at pH 3, and an eluent volume of 4 mL. The practical recoveries of theobromine and theophylline in green tea were 92.27% and 87.51%, respectively, with a corresponding actual extraction amount of 4.87 mg.g-1 and 5.07 mg.g-1. Overall, the proposed approach with the high affinity of Fe3O4/MIPs might offer a novel method for the purification of complex isomer samples. [ABSTRACT FROM AUTHOR]

The moss Physcomitrella patens is a model system for studying Plant developmental processes. To better understand the biochemical and physiological changes involved in developmental reprogramming, we conducted a quantitative proteomics analysis for protonemata, protoplasts made therefrom and protoplasts regenerated for 2 d. Using an iTRAQ peptide labeling strategy and liquid chromatography-tandem mass spectrometry (LC-MS/MS), >3,000 peptides and 1,000 proteins were quantified. Of these, 162 proteins were identified as having differential abundances during developmental reprogramming. These proteins were involved in various biological functions, such as defense, energy production, translation, metabolism, protein destination and storage, transcription, transport, cell growth/division, cell structure and signal transduction. Of these, the proteins involved in energy production and translation increased in abundance, while many of the metabolism and defense proteins decreased in abundance. In addition, most of the cell growth/division, protein stability and cell structure proteins were also down-regulated. This is the first report on the metabolic changes involved in developmental reprogramming in protoplasts. The significance of metabolic networks in developmental programming is beginning to emerge. Our study suggested that stress signals, energy metabolism and ribosomal proteins are pivotal components during developmental programming. [ABSTRACT FROM AUTHOR]

Harmonicity is a fundamental element of music, speech, and animal vocalizations. How the auditory system extracts harmonic structures embedded in complex sounds and uses them to form a coherent unitary entity is not fully understood. Despite the prevalence of sounds rich in harmonic structures in our everyday hearing environment, it has remained largely unknown what neural mechanisms are used by the primate auditory cortex to extract these biologically important acoustic structures. In this study, we discovered a unique class of harmonic template neurons in the core region of auditory cortex of a highly vocal New World primate, the common marmoset (Callithrixjacchus), across the entire hearing frequency range. Marmosets have a rich vocal repertoire and a similar hearing range to that of humans. Responses of these neurons show nonlinear facilitation to harmonic complex sounds over inharmonic sounds, selectivity for particular harmonic structures beyond two-tone combinations, and sensitivity to harmonic number and spectral regularity. Our findings suggest that the harmonic template neurons in auditory cortex may play an important role in processing sounds with harmonic structures, such as animal vocalizations, human speech, and music. [ABSTRACT FROM AUTHOR]

Despite the success of cochlear implants (CIs) in human populations, most users perform poorly in noisy environments and music and tonal language perception. How Cl devices engage the brain at the single neuron level has remained largely unknown, in particular in the primate brain. By comparing neuronal responses with acoustic and Cl stimulation in marmoset monkeys unilaterally implanted with a Cl electrode array, we discovered that Cl stimulation was surprisingly ineffective at activating many neurons in auditory cortex, particularly in the hemisphere ipsilateral to the Cl. Further analyses revealed that the Cl-nonresponsive neurons were narrowly tuned to frequency and sound level when probed with acoustic stimuli; such neurons likely play a role in perceptual behaviors requiring fine frequency and level discrimination, tasks that Cl users find especially challenging. These findings suggest potential deficits in central auditory processing of Cl stimulation and provide important insights into factors responsible for poor Cl user performance in a wide range of perceptual tasks. [ABSTRACT FROM AUTHOR]

Background: Diastolic dysfunction refers to an impaired relaxation and an abnormality in a heart's filling during diastole while left ventricular systolic function is preserved. Diastolic dysfunction is commonly observed in patients with primary hypertension, diabetes and cardiomyopathies such as hypertrophic cardiomyopathy or restrictive cardiomyopathy. We have generated a restrictive cardiomyopathy (RCM) mouse model with troponin mutations in the heart to mimic the human RCM patients carrying the same mutations. Results: In the present study, we have investigated the ventricular muscle internal dynamics and pressure developed during systole and diastole by inserting a micro-catheter into the left ventricle of the RCM mice with or without treatment of desensitizer green tea extracts catechins. Our results demonstrate that green tea catechin is able to correct diastolic dysfunction in RCM mainly by improving ventricular compliance and reducing the internal muscle rigidity caused by myofibril hypersensitivity to Ca2+. Conclusion: Green tea extract catechin is effective in correcting diastolic dysfunction and improving ventricular muscle intrinsic compliance in RCM caused by troponin mutations. [ABSTRACT FROM AUTHOR]

A series of new 2-phenyl-quinoline-4-carboxylic acid derivatives was synthesized starting from aniline, 2-nitrobenzaldehyde, pyruvic acid followed by Doebner reaction, amidation, reduction, acylation and amination. All of the newly-synthesized compounds were characterized by 1H-NMR, 13C-NMR and HRMS. The antibacterial activities of these compounds against Gram-negative (Escherichia coli, Pseudomonas aeruginosa) and Gram-positive bacteria (Staphylococcus aureus, Bacillus subtilis), as well as one strain of methicillin-resistant Staphylococcus aureus (MRSA) bacteria were evaluated by the agar diffusion method (zone of inhibition) and a broth dilution method (minimum inhibitory concentration (MIC)), and their structure-activity relationships were obtained and discussed. The results revealed that some compounds displayed good antibacterial activity against Staphylococcus aureus, and Compounds 5a4 and 5a7 showed the best inhibition with an MIC value of 64 μg/mL against Staphylococcus aureus and with an MIC value of 128 μg/mL against Escherichia coli, respectively. The results of the MTT assay illustrated the low cytotoxicity of Compound 5a4. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the effects of treatment with thymosin α1 (TA1) or interferon α (IFNα) following the establishment of severe acute pancreatitis (SAP) in rats. A total of 144 Sprague-Dawley rats were randomly divided into four groups. The rats in all four groups were celiotomized, and the rats in the control group were administered with an intravenous injection of saline. The three other groups were administered with 5% 1 ml/kg sodium taurocholate via the cholangiopancreatic duct. SAP group rats were administered with an intravenous injection of saline; TA1 group rats received 26.7 μg/kg TA1; and interferon α (INFα) group rats received 4.0x105 U/kg IFNα. The rats were anesthetized and blood samples were collected from the animals 3, 12 and 24 h after surgery. The levels of T cell subsets, serum enzyme indicators, cytokines and procalcitonin (PCT) were measured. The general conditions of the rats were observed until sacrifice, and pancreatic and lung tissue samples were sampled for hematoxylin and eosin staining and histological scoring. The expression levels of aspartate transaminase, lactate dehydrogenase, α-amylase (AMY), P-type-amylase, lipase, PCT, tumor-necrosis factor α, interleukin (IL)-4, IL-5, and IL-18 in the TA1 and IFNα-treated rats were significantly lower, compared with those of the SAP rats within the first 24 h of model establishment (P<0.05). The TA1 and IFNα-treated rats exhibited significantly increased levels of CD3+, CD4+ and CD8+ T cells, and an increased ratio of CD4+/CD8+ cells, compared with SAP rats. Histological analysis revealed that the TA1 and IFNα-treated rats exhibited significantly ameliorated pancreas and lung damage, and mortality rates were reduced from 50.0% (6/12) to 25.0% (3/12) and 33.3% (4/12), respectively. The immunomodulatory agents TA1 and IFNα reduced acute inflammation, decreasing cell damage and enhancing immune function and survival rates in the SAP rats. [ABSTRACT FROM AUTHOR]

Background: With increasing attention put on the methodology of reporting guidelines, Moher et al. conducted a review of reporting guidelines up to December 2009. Information gaps appeared on many aspects. Therefore, in 2010, the Guidance for Developers of Health Research Reporting Guidelines was developed. With more than four years passed and a considerable investment was put into reporting guideline development, a large number of new, updated, and expanded reporting guidelines have become available since January 2010. We aimed to systematically review the reporting guidelines published since January 2010, and investigate the application of the Guidance.Methods: We systematically searched databases including the Cochrane Methodology Register, MEDLINE, and EMBASE, and retrieved EQUATOR and the website (if available) to find reporting guidelines as well as their accompanying documents. We screened the titles and abstracts resulting from searches and extracted data. We focused on the methodology and reporting of the included guidelines, and described information with a series of tables and narrative summaries. Data were summarized descriptively using frequencies, proportions, and medians as appropriate.Results: Twenty-eight and 32 reporting guidelines were retrieved from databases and EQUATOR network, respectively. Reporting guidelines were designed for a broad spectrum of types of research. A considerable number of reporting guidelines were published and updated in recent years. Methods of initial items were given in 45 (75%) guidelines. Thirty-eight (63%) guidelines reported they have reached consensus, and 35 (58%) described their consensus methods. Only 9 (15%) guidelines followed the Guidance.Conclusions: Only few guidelines were developed complying with the Guidance. More attention should be paid to the quality of reporting guidelines. [ABSTRACT FROM AUTHOR]

One of the most common post-translational modifications is protein phosphorylation, which controls many activities of plant life. However, its role in the reprogramming of developmental pathways of plant cells remains elusive. Here, using Physcomitrella patens, we characterize the phospho-proteome for protonemata, protoplasts made therefrom, and protoplasts regenerated for 2 d. Through a titanium dioxide (TiO2)-based phospho-peptide enrichment method and liquid chromatography--tandem mass spectrometry (LC--MS/MS), more than 2000 phospho-proteins were identified. Among the 519 proteins with functional annotation in fresh protoplasts and protoplasts regenerated for 2 d, proteins involved in epigenetic modification, post-transcriptional gene regulation, hormone signal transduction, and meristem maintenance have been previously reported to be important for developmental reprogramming. Several novel transcription factors including SWI/SNF complex protein, SNF2 family protein and MADS-domain transcription factor appear to be important in developmental reprogramming plant cells. Phosphorylation of marker proteins such as somatic embryogenesis receptor kinase and NAC transcription factor, suggests that this post-translational modification is vital for the cell's ability to adjust its developmental program. Together, our study presents a more complete understanding of the plant cell's developmental reprogramming. [ABSTRACT FROM AUTHOR]

Auditory-vocal interaction, the modulation of auditory sensory responses during vocal production, is an important but poorly understood neurophysiological phenomenon in nonhuman primates. This sensory-motor processing has important behavioral implications for self-monitoring during vocal production as well as feedback-mediated vocal control for both animals and humans. Previous studies in marmosets have shown that a large portion of neurons in the auditory cortex are suppressed during self-produced vocalization but have primarily focused on a single type of isolation vocalization. The present study expands previous analyses to compare auditory-vocal interaction of cortical responses between different types of vocalizations. We recorded neurons from the auditory cortex of unrestrained marmoset monkeys with implanted electrode arrays and showed that auditory-vocal interactions generalize across vocalization types. We found the following: 1) Vocal suppression and excitation are a general phenomenon, occurring for all four major vocalization types. 2) Within individual neurons, suppression was the more general response, occurring for multiple vocalization types, while excitation tended to be more specific to a single vocalization type. 3) A subset of neurons changed their responses between different types of vocalization, most often from strong suppression or excitation for one vocalization to unresponsive for another, and only rarely from suppression to excitation. 4) Differences in neural responses between vocalization types were weakly correlated with passive response properties, measured by playbacks of acoustic stimuli including recorded vocalizations. These results indicate that vocalization-induced modulation of the auditory cortex is a general phenomenon applicable to all vocalization types, but variations within individual neurons suggest possible vocalization-specific coding. [ABSTRACT FROM AUTHOR]

We present a theoretical analysis of processes of pattern formation that involves organisms distribution and their interaction of spatially distributed population with cross-diffusion in a Harrison-type predator-prey model. We analyze the global behaviour of the model by establishing a Lyapunov function. We carry out the analytical study in detail and find out the certain conditions for Turing's instability induced by cross-diffusion. And the numerical results reveal that, on increasing the value of the half capturing saturation constant, the sequences "spots → spot-stripe mixtures → stripes → hole-stripe mixtures → holes" are observed. The results show that the model dynamics exhibits complex pattern replication controlled by the cross-diffusion. [ABSTRACT FROM AUTHOR]

We investigate the complex dynamics of a diffusive Holling-Tanner predation model with the Allee effect on prey analytically and numerically. We examine the existence of the positive equilibria and the related dynamical behaviors of themodel and find thatwhen themodel is with weak Allee effect, the solutions are local and global stability for some conditions around the positive equilibrium. In contrast, when the model is with strong Allee effect, this may lead to the phenomenon of bistability; that is to say, there is a separatrix curve that separates the behavior of trajectories of the system, implying that the model is highly sensitive to the initial conditions. Furthermore, we give the conditions of Turing instability and determine the Turing space in the parameters space. Based on these results, we perform a series of numerical simulations and find that the model exhibits complex pattern replication: spots, spots-stripes mixtures, and stripes patterns. The results show that the impact of the Allee effect essentially increases the models spatiotemporal complexity. [ABSTRACT FROM AUTHOR]

The reaction-diffusion Holling-Tanner prey-predator model considering the Allee effect on predator, under zero-flux boundary conditions, is discussed. Some properties of the solutions, such as dissipation and persistence, are obtained. Local and global stability of the positive equilibrium and Turing instability are studied. With the help of the numerical simulations, the rich Turing patterns, including holes, stripes, and spots patterns, are obtained. [ABSTRACT FROM AUTHOR]

Experiments in animals have provided an important complement to human studies of pitch perception by revealing how the activity of individual neurons represents harmonic complex and periodic sounds. Such studies have shown that the acoustical parameters associ-ated with pitch are represented by the spiking responses of neurons in Al (primary auditory cortex) and various higher auditory cortical fields. The responses of these neurons are also modulated by the timbre of sounds. In marmosets, a distinct region on the low-frequency border of primary and non-primary auditory cortex may provide pitch tuning that generalizes across timbre classes. [ABSTRACT FROM AUTHOR]

Sound localization in both humans and monkeys is tolerant to changes in sound levels. The underlying neural mechanism, however, is not well understood. This study reports the level dependence of individual neurons' spatial receptive fields (SRFs) in the primary auditory cortex (A1) and the adjacent caudal field in awake marmoset monkeys. We found that most neurons' excitatory SRF components were spatially confined in response to broadband noise stimuli delivered from the upper frontal sound field. Approximately half the recorded neurons exhibited little change in spatial tuning width over a ~20-dB change in sound level, whereas the remaining neurons showed either expansion or contraction in their tuning widths. Increased sound levels did not alter the percent distribution of tuning width for neurons collected in either cortical field. The population-averaged responses remained tuned between 30- and 80-dB sound pressure levels for neuronal groups preferring contralateral, midline, and ipsilateral locations. We further investigated the spatial extent and level dependence of the suppressive component of SRFs using a pair of sequentially presented stimuli. Forward suppression was observed when the stimuli were delivered from "far" locations, distant to the excitatory center of an SRF. In contrast to spatially confined excitation, the strength of suppression typically increased with stimulus level at both the excitatory center and far regions of an SRF. These findings indicate that although the spatial tuning of individual neurons varied with stimulus levels, their ensemble responses were level tolerant. Widespread spatial suppression may play an important role in limiting the sizes of SRFs at high sound levels in the auditory cortex. [ABSTRACT FROM AUTHOR]

Speaking is a sensory-motor process that involves constant self-monitoring to ensure accurate vocal production. Self-monitoring of vocal feedback allows rapid adjustment to correct perceived differences between intended and produced vocalizations. One important behavior in vocal feedback control is a compensatory increase in vocal intensity in response to noise masking during vocal production, commonly referred to as the Lombard effect. This behavior requires mechanisms for continuously monitoring auditory feedback during speaking. However, the underlying neural mechanisms are poorly understood. Here we show that when marmoset monkeys vocalize in the presence of masking noise that disrupts vocal feedback, the compensatory increase in vocal intensity is accompanied by a shift in auditory cortex activity toward neural response patterns seen during vocalizations under normal feedback condition. Furthermore, we show that neural activity in auditory cortex during a vocalization phrase predicts vocal intensity compensation in subsequent phrases. These observations demonstrate that the auditory cortex participates in self-monitoring during the Lombard effect, and may play a role in the compensation of noise masking during feedback-mediated vocal control. [ABSTRACT FROM AUTHOR]

Heterogeneous nuclear ribonucleoproteins (hnRNPs), which are chromatin- associated RNA-binding proteins, participate in mRNA stability, transport, intracellular localization, and translation by acting as transacting factors. Several studies have shown that steroid hormones can regulate hnRNP expression. However, to date, the regulation of hnRNPs and their interactions with steroid hormone signaling in fallopian tubes and endometrium are not fully elucidated. In the present study, we determined whether hnRNP expression is regulated during the menstrual cycle and correlates with estrogen receptor (ER) and progesterone receptor (PR) levels in human fallopian tubes in vivo. Because of the limited availability of human tubal tissues for the research, we also explored the mechanisms of hnRNP regulation in human endometrium in vitro. Fallopian tissue was obtained from patients in the early, late, and postovulatory phases and the midsecretory phase and endometrial tissue from premenopausal and postmenopausal women undergoing hysterectomy. We measured expression of hnRNPs and assessed their intracellular localization and interactions with ERs and PRs. We also determined the effects of human chorionic gonadotropin, 17β-estradiol (E2), and progesterone (P4) on hnRNP expression. In fallopian tubes, mRNA and protein levels of hnRNP A1, AB, D, G, H, and U changed dynamically during ovulation and in the midsecretory phase. In coimmunolocation and coimmunoprecipitation experiments, hnRNPs interacted with each other and with ERs and PRs in fallopian tubes. After treatment with E2 and/or P4 to activate ERs and PRs, hnRNP A1, AB, D, G, and U proteins displayed overlapping but distinct patterns of regulation in the endometrium in vitro. Our findings expand the physiological repertoire of hnRNPs in human fallopian tubes and endometrium and suggest that steroid hormones regulate different hnRNPs directly by interacting with ERs and/or PRs or indirectly by binding other hnRNPs. Both actions may contribute to regulation of gene transcription. [ABSTRACT FROM AUTHOR]

A quinidine-derived squaramide Ib catalyzed cyclization reaction of β-oxo aldehydes 1 and aliphatic or aromatic β,γ-unsaturated α-keto ester 2 is described. Using cyclic aldehyde substrates, this procedure provided a promising approach to a variety of spiro-3,4-dihydropyrans bearing three continuous quaternary and tertiary stereocenters in moderate to good yield with high stereoselectivities. Substituents on the nitrogen atoms of the squaramide moiety of the catalyst proved crucial to the reaction outcome. The stereochemistry of the three newly formed chiral centers (trans-selective) of the major product indicates a Micheal addition/hemiacetalization domino sequence for the present annulations. [ABSTRACT FROM AUTHOR]

We construct a new Lyapunov function for a class of predation models. Global stability of the positive equilibrium states of these systems can be established when the Lyapunov function is used. [ABSTRACT FROM AUTHOR]

As the information bottleneck of nearly all auditory input that reaches the cortex, the auditory thalamus serves as the basis for establishing auditory cortical processing streams. The functional organization of the primary and nonprimary subdivisions of the auditory thalamus is not well characterized, particularly in awake primates. We have recorded from neurons in the auditory thalamus of awake marmoset monkeys and tested their responses to tones, bandpass noise, and temporally modulated stimuli. We analyzed the spectral and temporal response properties of recorded neurons and correlated those properties with their locations in the auditory thalamus, thereby forming the basis for parallel output channels. Three medial geniculate body (MGB) subdivisions were identified and studied physiologically and anatomically, although other medial subdivisions were also identified anatomically. Neurons in the ventral subdivision (MGV) were sharply tuned for frequency, preferred narrowband stimuli, and were able to synchronize to rapid temporal modulations. Anterodorsal subdivision (MGAD) neurons appeared well suited for temporal processing, responding similarly to tone or noise stimuli but able to synchronize to the highest modulation frequencies and with the highest temporal precision among MGB subdivisions. Posterodorsal subdivision (MGPD) neurons differed substantially from the other two subdivisions, with many neurons preferring broadband stimuli and signaling changes in modulation frequency with nonsynchronized changes in firing rate. Most neurons in all subdivisions responded to increases in tone sound level with nonmonotonic changes in firing rate. MGV and MGAD neurons exhibited responses consistent with provision of thalamocortical input to core regions, whereas MGPD neurons were consistent with provision of input to belt regions. [ABSTRACT FROM AUTHOR]

How sounds are processed by the brain during sleep is an important question for understanding how we perceive the sensory environment in this unique behavioral state. While human behavioral data have indicated selective impairments of sound processing during sleep, brain imaging and neurophysiology studies have reported that overall neural activity in auditory cortex during sleep is surprisingly similar to that during wakefulness. This responsiveness to external stimuli leaves open the question of how neural responses during sleep differ, if at all, from wakefulness. Using extracellular neural recordings in the primary auditory cortex of naturally sleeping common marmosets, we show that slow-wave sleep (SWS) alters neural responses in the primate auditory cortex in two specific ways. SWS reduced the sensitivity of auditory cortex such that quiet sounds elicited weak responses in SWS compared with wakefulness, while loud sounds evoked similar responses in SWS and wakefulness. Furthermore, SWS reduced the extent of sound-evoked response suppression. This pattern of alterations was not observed during rapid eye movement sleep and could not be easily explained by the presence of slow rhythms in SWS. The alteration of excitatory and inhibitory responses during SWS suggests limitations in auditory processing and provides novel insights for understanding why certain sounds are processed while others are missed during deep sleep. [ABSTRACT FROM AUTHOR]

Slow envelope fluctuations in the range of 2-20 Hz provide important segmental cues for processing communication sounds. For a successful segmentation, a neural processor must capture envelope features associated with the rise and fall of signal energy, a process that is often challenged by the interference of background noise. This study investigated the neural representations of slowly varying envelopes in quiet and in background noise in the primary auditory cortex (Al) of awake marmoset monkeys. We characterized envelope features based on the local average and rate of change of sound level in envelope waveforms and identified envelope features to which neurons were selective by reverse correlation. Our results showed that envelope feature selectivity of Al neurons was correlated with the degree of nonmonotonicity in their static rate-level functions. Nonmonotonic neurons exhibited greater feature selectivity than monotonic neurons in quiet and in background noise. The diverse envelope feature selectivity decreased spike-timing correlation among Al neurons in response to the same envelope waveforms. As a result, the variability, but not the average, of the ensemble responses of Al neurons represented more faithfully the dynamic transitions in low-frequency sound envelopes both in quiet and in background noise. [ABSTRACT FROM AUTHOR]

Slow envelope fluctuations in the range of 2-20 Hz provide important segmental cues for processing communication sounds. For a successful segmentation, a neural processor must capture envelope features associated with the rise and fall of signal energy, a process that is often challenged by the interference of background noise. This study investigated the neural representations of slowly varying envelopes in quiet and in background noise in the primary auditory cortex (A1) of awake marmoset monkeys. We characterized envelope features based on the local average and rate of change of sound level in envelope waveforms and identified envelope features to which neurons were selective by reverse correlation. Our results showed that envelope feature selectivity of A1 neurons was correlated with the degree of nonmonotonicity in their static rate-level functions. Nonmonotonic neurons exhibited greater feature selectivity than monotonic neurons in quiet and in background noise. The diverse envelope feature selectivity decreased spike-timing correlation among A1 neurons in response to the same envelope waveforms. As a result, the variability, but not the average, of the ensemble responses of A1 neurons represented more faithfully the dynamic transitions in low-frequency sound envelopes both in quiet and in background noise. [ABSTRACT FROM AUTHOR]

The prognostic value of karyotype in patients with myelodysplastic syndrome (MDS) is generally appreciated. However, the factors that are predictive of prognosis of patients with abnormal karyotypes are not known. In this study, we evaluated the prognostic value of International Prognostic Scoring System (IPSS) and World Health Organization classification-based prognostic scoring system (WPSS) in 164 adult MDS patients with abnormal karyotypes. We also analyzed the prognostic relevance of mean corpuscular volume (MCV) in these patients. We found that both IPSS and WPSS had strong prognostic value in patients with abnormal karyotypes ( P < 0.001, P < 0.001). Furthermore, we observed the significant differences in the survival of patients with abnormal karyotypes based on MCV stratification: The median survival of patients with macrocytosis was 31.0 months, significantly longer than the 16.5-month median survival time of patients with MCVs of less than 100 fl ( P = 0.001). Multivariate analysis revealed that lower level of hemoglobin ( P = 0.012, HR = 6.83), higher level of marrow blasts ( P < 0.001, HR = 1.93), complex karyotype ( P = 0.001, HR = 3.32), and MCV of less than 100 fl ( P = 0.026, HR = 1.75) were independent risk factors that affected the survival of patients with abnormal karyotypes. [ABSTRACT FROM AUTHOR]

Recent studies have demonstrated the high selectivity of neurons in primary auditory cortex (A1) and a highly sparse representation of sounds by the population of A1 neurons in awake animals. However, the underlying receptive field structures that confer high selectivity on A1 neurons are poorly understood. The sharp tuning of A1 neurons' excitatory receptive fields (RFs) provides a partial explanation of the above properties. However, it remains unclear how inhibitory components of RFs contribute to the selectivity of A1 neurons observed in awake animals. To examine the role of the inhibition in sharpening stimulus selectivity, we have quantitatively analyzed stimulus induced suppressive effects over populations of single neurons in frequency, amplitude, and time in A1 of awake marmosets. In addition to the well documented short-latency side-band suppression elicited by masking tones around the best frequency (BF) of a neuron, we uncovered long-latency suppressions caused by single-tone stimulation. Such long-latency suppressions also included monotonically increasing suppression with sound level both on-BF and off-BF, and persistent suppression lasting up to 100 ms after stimulus offset in a substantial proportion of A1 neurons. The extent of the suppression depended on the shape of a neuron's frequency-response area ("O" or "V" shaped). These findings suggest that the excitatory RF of A1 neurons is cocooned by ide-ranging inhibition that contributes to the high selectivity in A1 neurons' responses to complex stimuli. Population sparseness of the tone-responsive A1 neuron population may also be a consequence of this pervasive inhibition. [ABSTRACT FROM AUTHOR]

Background: Local hyperthermia has been successfully used in the treatment of viral warts. However, the mechanism of action has largely remained unclear. CCL-20 (also known as MIP-3α) is the most potent chemokine for recruitment of Langerhans cell (LC) precursors into the skin. CCL-20 expression can be increased by TNF-α and IL-1α. The effects of local hyperthermia on the mRNA expressions of CCL-20, TNF-α, IL-1α have been investigated in both condyloma acuminata (CA) and normal skin. Under an organotypic culture condition, fresh CA and normal skin were subjected to surface heating at 37°C, 42°C and 45°C for 30 mins, respectively. Results: The mRNA expressions of CCL-20 and IL-1α in CA specimen were significantly higher than those in normal skin. Local hyperthermia at 42°C and 45°C significantly decreased the mRNA levels of CCL-20 and IL-1α, as compared with the control groups (p < 0.01). The decrease of CCL-20 was well correlated with that of IL-1α. The expression of TNF-a in CA remained unchanged in spite of the temperature variation. Local hyperthermia at 45°C concomitantly increased the mRNA expression of CCL-20 and IL-1α in normal skin. Conclusions: Our study suggests that hyperthermia decreases the expression of CCL-20 with concomitant decrease in IL-1α, and reduce the number of Langerhans cells in HPV infected skin. [ABSTRACT FROM AUTHOR]

Background: The plant hormone abscisic acid (ABA) is ubiquitous among land plants where it plays an important role in plant growth and development. In seeds, ABA induces embryogenesis and seed maturation as well as seed dormancy and germination. In vegetative tissues, ABA is a necessary mediator in the triggering of many of the physiological and molecular adaptive responses of the plant to adverse environmental conditions, such as desiccation, salt and cold. Results: In this study, we investigated the influence of abscisic acid (ABA) on Physcomitrella patens at the level of the proteome using two-dimensional gel electrophoresis (2-DE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Sixty-five protein spots showed changes in response to ABA treatment. Among them, thirteen protein spots were down-regulated; fifty-two protein spots were up-regulated including four protein spots which were newly induced. These proteins were involved in various functions, including material and energy metabolism, defense, protein destination and storage, transcription, signal transduction, cell growth/division, transport, and cytoskeleton. Specifically, most of the up-regulated proteins functioned as molecular chaperones, transcriptional regulators, and defense proteins. Detailed analysis of these up-regulated proteins showed that ABA could trigger stress and defense responses and protect plants from oxidative damage. Otherwise, three protein kinases involved in signal pathways were up-regulated suggesting that P. patens is sensitive to exogenous ABA. The down-regulated of the Rubisco small subunit, photosystem II oxygen-evolving complex proteins and photosystem assembly protein ycf3 indicated that photosynthesis of P. patens was inhibited by ABA treatment. Conclusion: Proteome analysis techniques have been applied as a direct, effective, and reliable tool in differential protein expressions. Sixty-five protein spots showed differences in accumulation levels as a result of treatment with ABA. Detailed analysis these protein functions showed that physiological and molecular responses to the plant hormone ABA appear to be conserved among higher plant species and bryophytes. [ABSTRACT FROM AUTHOR]

In the auditory cortex of awake animals, a substantial number of neurons do not respond to pure tones. These neurons have historically been classified as "unresponsive" and even been speculated as being nonauditory. We discovered, however, that many of these neurons in the primary auditory cortex (A1) of awake marmoset monkeys were in fact highly selective for complex sound features. We then investigated how such selectivity might arise from the tone-tuned inputs that these neurons likely receive. We found that these non-tone responsive neurons exhibited nonlinear combination-sensitive responses that require precise spectral and temporal combinations of two tone pips. The nonlinear spectro temporal maps derived from these neurons were correlated with their selectivity for complex acoustic features. These non-tone responsive and nonlinear neurons were commonly encountered at superficial cortical depths in A1. Our findings demonstrate how temporally and spectrally specific nonlinear integration of putative tone-tuned inputs might under lie a diverse range of high selectivity of A1 neurons in awake animals. We propose that describing A1 neurons with complex response properties in terms of tone-tuned input channels can conceptually unify a wide variety of observed neural selectivity to complex sounds into a lower dimensional description. [ABSTRACT FROM AUTHOR]

Material systems are needed that promote stabilization of entrained molecules, such as enzymes or therapeutic proteins, without destroying their activity. We demonstrate that the unique structure of silk fibroin protein, when assembled into the solid state, establishes an environment that is conducive to the stabilization of entrained proteins. Enzymes (glucose oxidase, lipase, and horseradish peroxidase) entrapped in these films over 10 months retained significant activity, even when stored at 37 °C, and in the case of glucose oxidase did not lose any activity. Further, the mode of processing of the silk protein into the films could be correlated to the stability of the enzymes. The relationship between processing and stability offers a large suite of conditions within which to optimize such stabilization processes. Overall, the techniques reported here result in materials that stabilize enzymes to an extent, without the need for cryoprotectants, emulsifiers, covalent immobilization, or other treatments. Further, these systems are amenable to optical applications and characterization, environmental distribution without refrigeration, are ingestible, and offer potential use in vivo, because silk materials are biocompatible and FDA approved, degradable with proteases, and currently used in biomedical devices. [ABSTRACT FROM AUTHOR]

Most sensory stimuli do not reach conscious perception during sleep. It has been thought that the thalamus prevents the relay of sensory information to cortex during sleep, but the consequences for cortical responses to sensory signals in this physiological state remain unclear. We recorded from two auditory cortical areas downstream of the thalamus in naturally sleeping marmoset monkeys. Single neurons in primary auditory cortex either increased or decreased their responses during sleep compared with wakefulness. In lateral belt, a secondary auditory cortical area, the response modulation was also bidirectional and showed no clear systematic depressive effect of sleep. When averaged across neurons, sound-evoked activity in these two auditory cortical areas was surprisingly well preserved during sleep. Neural responses to acoustic stimulation were present during both slow-wave and rapid-eye movement sleep, were repeatedly observed over multiple sleep cycles, and demonstrated similar discharge patterns to the responses recorded during wakefulness in the same neuron. Our results suggest that the thalamus is not as effective a gate for the flow of sensory information as previously thought. At the cortical stage, a novel pattern of activation/deactivation appears across neurons. Because the neural signal reaches as far as secondary auditory cortex, this leaves open the possibility of altered sensory processing of auditory information during sleep. [ABSTRACT FROM AUTHOR]

Objective: To examine the interaction between salt-intake and helicobacter pylori (H. pylori) infection in the development of stomach cancer in an ecological study of 67 Chinese rural counties. Methods: Stomach cancer mortality data of 67 counties were derived from a national survey conducted in China between 1986 and 1988. Information regarding the prevalence of H. pylori infection and urinary sodium excretion were collected from the same individuals during a subsequent dietary survey in 1989. Results: In these 67 counties, H. pylori prevalence and urinary sodium were correlated with stomach cancer mortality, with r=0.31 (p=0.01) and r=0.28 (p=0.03), respectively. After stratification, the significant correlation between H. pylori prevalence and stomach cancer mortality only existed in counties with high levels (≥5.0 mg/mg creatinine/12-hour) of urinary sodium (r=0.5; p=0.002). Similarly, the significant correlation between urinary sodium and stomach cancer mortality was only presented in counties with high (≥71.6%) H. pylori prevalence (r=0.4; p=0.017). Multivariate regression analysis showed results consistent with the correlation analysis. Conclusion: These findings suggest that there may be an interaction between high salt consumption and H .pylori infection in the development of stomach cancer. Corroborating data from epidemiological, clinical, and experimental studies are needed. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the validity of a Xi'an food frequency questionnaire (FFQ) designed for application in an international case-control colorectal cancer study. The FFQ was administered to 125 participants twice over 1-year interval. Four 24-hour dietary recalls (24-HDRs) were conducted with the same participants in each season of the year. Comparative validation was assessed by comparing the nutrient intakes derived from the 24-HDRs and the FFQ-2, and reproducibility was estimated by comparing the nutrient intakes from two FFQs. In the validation study, the mean deattenuated correlation coefficients for nutrients between the 24-HDRs and the FFQ-2 ranged from 0.35 to 0.84 in the males. The female results were slightly lower than the male's. The mean percentage of classification into the same quartile was 38% for the males and 35% for the females. In the reproducibility study, the mean crude correlation coefficients between the two FFQs were from 0.41 to 0.68 in the males and from 0.36 to 0.66 in the females. The newly developed Xi'an FFQ appears to be reasonably valid and reliable for most nutrients but would benefit from the addition of nutritional supplements and seasonings for assessing dietary intake in older persons in Xi'an, China. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the effect of Salvia miltiorrhiza on the production of plasminogen activator inhibitor-1(PAI-1) induced by angiotensin II (Ang II) in renal mesangial cells. Rat mesangial cells were exposed to 100 nM Ang II. Meanwhile, different concentrations of Salvia miltiorrhiza injection were added to Mesangial Cells. PAI-1 mRNA was measured by semi-quantification reverse transcriptase polymerase chain reaction (RT-PCR) and PAI-1 protein by Western blotting. ELISA was used to detect the expression of transforming growth factor β1 (TGF-β1) in serum free MEM medium. The level of cellular reactive oxygen species (ROS) was measured by confocal laser scanning microscopy. Salvia miltiorrhiza notably attenuated expression of PAI-1 induced by Ang II in a concentration-dependent manner. Meanwhile, it suppressed the production of TGF-β1 and cellular ROS in mesangial cells. These effects were due to Salvia miltiorrhiza's ability of inhibiting the activities of angiotensin II. Therefore, Salvia miltiorrhiza can be used to retard progression of glomerular sclerosis. [ABSTRACT FROM AUTHOR]

Vocal communication involves both speaking and hearing, often taking place concurrently. Vocal production, including human speech and animal vocalization, poses a number of unique challenges for the auditory system. It is important for the auditory system to monitor external sounds continuously from the acoustic environment during speaking despite the potential for sensory masking by self-generated sounds. It is also essential for the auditory system to monitor feedback of one’s own voice. This self-monitoring may play a part in distinguishing between self-generated or externally generatedauditory inputs and in detecting errors in our vocal production. Previous work in humans and other animals has demonstrated that the auditory cortex is largely suppressed during speaking or vocalizing. Despite the importance of self-monitoring, the underlying neural mechanisms in the mammalian brain, in particular the role of vocalization-induced suppression, remain virtually unknown. Here we show that neurons in the auditory cortex of marmoset monkeys (Callithrix jacchus) are sensitive to auditory feedback during vocal production, and that changes in the feedback alter the coding properties of these neurons. Furthermore, we found that the previously described cortical suppression during vocalization actually increased the sensitivity of these neurons to vocal feedback. This heightened sensitivity to vocal feedback suggests that these neurons may have an important role in auditory self-monitoring. [ABSTRACT FROM AUTHOR]

A fundamental feature of auditory perception is the constancy of sound recognition over a large range of intensities. Although this invariance has been described in behavioral studies, the underlying neural mechanism is essentially unknown. Here we show a putative level-invariant representation of sounds by populations of neurons in primary auditory cortex (A1) that may provide a neural basis for the behavioral observations. Previous studies reported that pure-tone frequency tuning of most A1 neurons widens with increasing sound level. In sharp contrast, we found that a large proportion of neurons in A1 of awake marmosets were narrowly and separably tuned to both frequency and sound level. Tuning characteristics and firing rates of the neural population were preserved across all tested sound levels. These response properties lead to a level-invariant representation of sounds over the population of A1 neurons. Such a representation is an important step for robust feature recognition in natural environments. [ABSTRACT FROM AUTHOR]

Background: Asthma is a complex disease, characterized by reversible airway obstruction, hyperresponsiveness and chronic inflammation. Principle pharmacologic treatments for asthma include bronchodilating beta2-agonists and anti-inflammatory glucocorticosteroids; but these agents do not target the main cause of the disease, the generation of pathogenic Th2 cells. We previously reported reduction in allergic inflammation in mice deficient in the ANP receptor NPRA. Here we determined whether siRNA for natriuretic peptide receptor A (siNPRA) protected against asthma when administered transdermally. Methods: Imiquimod cream mixed with chitosan nanoparticles containing either siRNA green indicator (siGLO) or siNPRA was applied to the skin of mice. Delivery of siGLO was confirmed by fluorescence microscopy. The anti-inflammatory activity of transdermal siNPRA was tested in OVA-sensitized mice by measuring airway hyperresponsiveness, eosinophilia, lung histopathology and pro-inflammatory cytokines. Results: SiGLO appearing in the lung proved the feasibility of transdermal delivery. In a mouse asthma model, BALB/c mice treated with imiquimod cream containing siNPRA chitosan nanoparticles showed significantly reduced airway hyperresponsiveness, eosinophilia, lung histopathology and pro-inflammatory cytokines IL-4 and IL-5 in lung homogenates compared to controls. Conclusion: These results demonstrate that topical cream containing imiquimod and siNPRA nanoparticles exerts an anti-inflammatory effect and may provide a new and simple therapy for asthma. [ABSTRACT FROM AUTHOR]

A sequence of acoustic events is perceived either as one continuous sound or as a stream of temporally discrete sounds (acoustic flutter), depending on the rate at which the acoustic events repeat. Acoustic flutter is perceived at repetition rates near or below the lower limit for perceiving pitch, and is akin to the discrete percepts of visual flicker and tactile flutter caused by the slow repetition of sensory stimulation. It has been shown that slowly repeating acoustic events are represented explicitly by stimulus-synchronized neuronal firing patterns in primary auditory cortex (AI). Here we show that a second neural code for acoustic flutter exists in the auditory cortex of marmoset monkeys (Callithrix jacchus), in which the firing rate of a neuron is a monotonic function of an acoustic event's repetition rate. Whereas many neurons in AI encode acoustic flutter using a dual temporal/rate representation, we find that neurons in cortical fields rostral to AI predominantly use a monotonic rate code and lack stimulus-synchronized discharges. These findings indicate that the neural representation of acoustic flutter is transformed along the caudal-to-rostral axis of auditory cortex. [ABSTRACT FROM AUTHOR]

African Americans have twice the prevalence of type 2 diabetes as Caucasians and much greater genetic diversity. We identified an inframe insertion of a proline in the insulin promoter factor 1 (IPF1) gene (InsCCG243), which was relatively common (minor allele frequency ∼0.08) in African Americans and showed a trend to association with type 2 diabetes in preliminary studies. An earlier French study identified InsCCG243 as a cause of autosomal dominant diabetes. To determine the role of this variant in African Americans, we examined an additional population from North Carolina (n = 368) and a subset of African-American participants from the Atherosclerosis Risk in Communities (ARIC) study (n = 1,741). We also looked for segregation in 66 African-American families and for a role in insulin secretion in 112 nondiabetic subjects. InsCCG243 did not increase the risk of type 2 diabetes (P = 0.16 in North Carolina; P = 0.97 in the ARIC study) and did not segregate with type 2 diabetes in families. However, we found suggestive evidence for reduced insulin response to glucose (P = 0.05). Neither indirect measures of β-cell mass nor β-cell compensation were altered (P > 0.1). InsCCG243 does not act in a dominant, highly penetrant fashion in African Americans and is not a significant risk factor for type 2 diabetes in this population. Diabetes 55:2909-2914, 2006 [ABSTRACT FROM AUTHOR]

We report a prospective study of 174 unselected adult de novo acute myeloid leukemia (AML) cases diagnosed using the WHO classification. Of those, 57 (33%) were AML with recurrent cytogenetic abnormalities, 41 were (24%) AML with multilineage dysplasia, 74 (42%) were AML not otherwise categorized, and two were acute leukemias of ambiguous lineage. Clonal cytogenetic abnormalities were detected in 64% of the WHO AML cases with t(15;17) (15%), t(8;21) (12%), +8 (11%), −7/del7q (8%) and del9q (5%) being the most common ones. The FLT3/ITD mutations ( FMS-like tyrosine kinase 3/internal tandem duplication) were observed in 12% of the WHO AML cases, which is much lower than ones in the literature, while the 6% incidence of the FLT3-activating loop mutations (either FLT3/D835 or FLT3/I836) was comparable with others. Both mutations were associated with leukocytosis. Our study also suggests that the FLT3 mutations are biomarkers independent of cytogenetic characteristics. [ABSTRACT FROM AUTHOR]

Most studies investigating neural representations of species-specific vocalizations in non-human primates and other species have involved studying neural responses to vocalization tokens. One limitation of such approaches is the difficulty in determining which acoustical features of vocalizations evoke neural responses. Traditionally used filtering techniques are often inadequate in manipulating features of complex vocalizations. Furthermore, the use of vocalization tokens cannot fully account for intrinsic stochastic variations of vocalizations that are crucial in understanding the neural codes for categorizing and discriminating vocalizations differing along multiple feature dimensions. In this work, we have taken a rigorous and novel approach to the study of species-specific vocalization processing by creating parametric "virtual vocalization" models of major call types produced by the common marmoset (Callithrix jacchus). The main findings are as follows. 1) Acoustical parameters were measured from a database of the four major call types of the common marmoset. This database was obtained from eight different individuals, and for each individual, we typically obtained hundreds of samples of each major call type. 2) These feature measurements were employed to parameterize models defining representative virtual vocalizations of each call type for each of the eight animals as well as an overall species-representative virtual vocalization averaged across individuals for each call type. 3) Using the same feature-measurement that was applied to the vocalization samples, we measured acoustical features of the virtual vocalizations, including features not explicitly modeled and found the virtual vocalizations to be statistically representative of the callers and call types. 4) The accuracy of the virtual vocalizations was further confirmed by comparing neural responses to real and synthetic virtual vocalizations recorded from awake marmoset auditory cortex. We found a strong agreement between the responses to token vocalizations and their synthetic counterparts. 5) We demonstrated how these virtual vocalization stimuli could be employed to precisely and quantitatively define the notion of vocalization "selectivity" by using stimuli with parameter values both within and outside the naturally occurring ranges. We also showed the potential of the virtual vocalization stimuli in studying issues related to vocalization categorizations by morphing between different call types and individual callers. [ABSTRACT FROM AUTHOR]

Background: Betacellulin is a member of the epidermal growth factor family, expressed at the highest levels predominantly in the pancreas and thought to be involved in islet neogenesis and regeneration. Nonsynonymous coding variants were reported to be associated with type 2 diabetes in African American subjects. We tested the hypotheses that these previously identified variants were associated with type 2 diabetes in African Americans ascertained in Arkansas and that they altered insulin secretion in glucose tolerant African American subjects. Methods: We typed three variants, exon1 Cys7Gly (C7G), exon 2 Leu44Phe (L44F), and exon 4 Leu124Met (L124M), in 188 control subjects and 364 subjects with type 2 diabetes. We tested for altered insulin secretion in 107 subjects who had undergone intravenous glucose tolerance tests to assess insulin sensitivity and insulin secretion. Results: No variant was associated with type 2 diabetes, and no variant altered insulin secretion or insulin sensitivity. However, an effect on lipids was observed for all 3 variants, and variant L124M was associated with obesity measures. Conclusion: We were unable to confirm a role for nonsynonymous variants of betacellulin in the propensity to type 2 diabetes or to impaired insulin secretion. [ABSTRACT FROM AUTHOR]

A fundamental issue in neuroscience pertains to how different cortical systems interact to generate behavior. One of the most direct ways to address this issue is to investigate how sensory information is encoded and used to produce a motor response. Antiphonal calling is a natural vocal behavior that involves individuals producing their species-specific long distance vocalization in response to hearing the same call and engages both the auditory and motor systems, as well as the cognitive neural systems involved in decision making and categorization. Here we present results from a series of behavioral experiments investigating the auditory–vocal interactions during antiphonal calling in the common marmoset ( Callithrix jacchus). We manipulated sensory input by placing subjects in different social contexts and found that the auditory input had a significant effect on call timing and propensity to call. Playback experiments tested the significance of the timing of vocal production in antiphonal calling and showed that a short latency between antiphonal calls was necessary to maintain reciprocal vocal interactions. Overall, this study shows that sensory-motor interactions can be experimentally induced and manipulated in a natural primate vocal behavior. Antiphonal calling represents a promising model system to examine these issues in non-human primates at both the behavioral and neural levels. [ABSTRACT FROM AUTHOR]

Abstract: The chemical polishing process and the subsequent passivation process of CdZnTe wafers were studied. The treatment effects were tested through XPS analysis and I–V measurement. The chemical etching in 2%Br–MeOH solution may effectively remove the damaged layer and improve the ohmic contact between CdZnTe wafer and Au electrodes. CdZnTe wafers after Br–MeOH etching were passivated with five different passivants respectively. It was found that the surface leakage currents of all CdZnTe wafers passivated with different passivants were reduced by 1–2 orders. CdZnTe wafer passivated in NH4F/H2O2 solution showed the best passivation efficiency because the enriched Te on the surface was fully oxidized to TeO2, which results in the thickest oxide layer, the most stoichiometric surface and the least leakage current. The surface of CdZnTe wafer is Te-rich after passivated in NH4F/H2O2 or H2O2 solution and Cd-rich after passivated in KOH or KOH/H2O2 solution. [Copyright &y& Elsevier]

A sound embedded in an acoustic stream cannot be unambiguously segmented and identified without reference to its stimulus context. To understand the role of stimulus context in cortical processing, we investigated the responses of auditory cortical neurons to 2-sound sequences in awake marmosets, with a focus on stimulus properties other than carrier frequency. Both suppressive and facilitatory modulations of cortical responses were observed by using combinations of modulated tone and noise stimuli. The main findings are as follows. 1) Preceding stimuli could suppress or facilitate responses to succeeding stimuli for durations >1 s. These long-lasting effects were dependent on the duration, sound level, and modulation parameters of the preceding stimulus, in addition to the carrier frequency. They occurred regardless of whether the 2 stimuli were separated by a silent interval. 2) Suppression was often tuned such that preceding stimuli whose parameters were similar to succeeding stimuli produced the strongest suppression. However, the responses of many units could be suppressed, although often weaker, even when the 2 stimuli were dissimilar. In some cases, only a dissimilar preceding stimulus produced suppression in the responses to the succeeding stimulus. 3) In contrast to suppression, facilitation of responses to succeeding stimuli by the preceding stimulus was usually strongest when the 2 stimuli were dissimilar. 4) There was no clear correlation between the firing rate evoked by the preceding stimulus and the change in the firing rate evoked by the succeeding stimulus, indicating that the observed suppression was not simply a result of habituation or spike adaptation. These results demonstrate that persistent modulations of the responses of an auditory cortical neuron to a given stimulus can be induced by preceding stimuli. Decreases or increases of responses to the succeeding stimuli are dependent on the spectral, temporal, and intensity properties of the preceding stimulus. This indicates that cortical auditory responses to a sound are not static, but instead depend on the stimulus context in a stimulus-specific manner. The long-lasting impact of stimulus context and the prevalence of facilitation suggest that such cortical response properties are important for auditory processing beyond forward masking, such as for auditory streaming and segregation. [ABSTRACT FROM AUTHOR]