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Different from normal-hearing (NH) listeners, speech recognition thresholds (SRTs) in cochlear implant (CI) users are typically poorer with dynamic maskers than with speech-spectrum noise (SSN). The effectiveness of different masker types may depend on their acoustic and linguistic characteristics. The goal of the present study was to evaluate the effectiveness of different masker types with varying acoustic and linguistic properties in CI and NH listeners. SRTs were measured with nine maskers, including SSN, dynamic nonspeech maskers, and speech maskers with or without lexical content. Results showed that CI users performed significantly poorer than NH listeners with all maskers. NH listeners were much more sensitive to masker type than were CI users. Relative to SSN, NH listeners experienced significant masking release for most maskers, which could be well explained by the glimpse proportion, especially for maskers containing similar cues related to fundamental frequency or lexical content. In contrast, CI users generally experienced negative masking release. There was significant intercorrelation among the maskers for CI users' SRTs but much less so for NH listeners' SRTs. Principal component analysis showed that one factor explained 72% of the variance in CI users' SRTs but only 55% in NH listeners' SRTs across all maskers. Taken together, the results suggest that SRTs in SSN largely accounted for the variability in CI users' SRTs with dynamic maskers. Different from NH listeners, CI users appear to be more susceptible to energetic masking and do not experience a release from masking with dynamic envelopes or speech maskers. [ABSTRACT FROM AUTHOR]

The Chang 7 member in Ordos Basin is an important shale oil exploration layer, with new shale-oil discoveries in recent years. The Chang 73 submember is rich in organic shale, which is the main source rock of shale oil in the Yanchang Formation. In order to clarify the lamina structure, composition, types, and distribution characteristics in Chang 73 submember and its influence on organic matter enrichment, a full coring well in Chang 73 submember located in deep-lacustrine facies is selected to obtain intensive systematic core samples. Core observation, thin section identification, X-ray fluorescence element analysis, X-diffraction analysis, scanning electron microscope, electron probe, rock pyrolysis, and other techniques are performed to systematically analyze the morphology, structure, thickness, mineral compositions, and organic matter content of the shale lamina in the Chang 73 submember. Five types of lamina are identified: silty felsic lamina (SF), tuffaceous lamina (TF), organic-rich clay lamina (ORC), organic-bearing clay lamina (OBC), and homogeneous clay lamina (HC), which are further subdivided into eight subtypes. The lamina types change greatly vertically in the Chang 73 submember, in which the lower part is mainly silty felsic lamina, organic-rich clay, and tuffaceous lamina, the middle part is mainly organic rich and organic clay lamina and organic-bearing clay lamina, and the upper part is mainly homogeneous clay lamina and a small amount of silty felsic organic-bearing clay lamina and organic-bearing clay lamina. Different laminae show various organic matter types, organic matter content (TOC), and organic matter occurrence states which can be divided into four occurrence types. The TOC in organic-rich clay lamina and part of homogeneous clay lamina is high, while that of silty felsic lamina is lower. The relationship between shale lamina and organic matter enrichment is established according to the correlation analysis of laminar characteristics, mineral content, and organic matter content. Among them, the organic-rich lamina is richest of TOC and is a favorable "sweet point" for shale oil exploration. [ABSTRACT FROM AUTHOR]

Ototoxic hearing loss results from hair cell death via reactive oxygen species (ROS) overproduction and consequent apoptosis. We investigated the effects of vitamin C (VC) on neomycin-induced HEI-OC1 cell damage, as well as the mechanism of inhibition. HEI-OC1 cells were treated with neomycin or with vitamin C (VC). The results indicated that VC had a protective effect on neomycin-induced HEI-OC1 cell death. Mechanistically, VC decreased neomycin-induced ROS generation, suppressed cell death, and increased cell viability. VC inhibited neomycin-induced apoptosis, ameliorated neomycin reduced antiapoptotic Bcl-2 expression, and suppressed neomycin increased expression of proapoptotic Bax, caspase-3 cleavage and caspase-8. TUNEL labeling demonstrated that VC blocked neomycin-induced apoptosis. Further study revealed that the effect of VC on neomycin-induced hair cell death was through interference with JNK activation and p38 phosphorylation. These results indicate that VC via suppressed ROS generation, which inhibited cell death by counteracting apoptotic signaling induced by neomycin in cells. Hence, VC is a potential candidate for protection agent against neomycin-induced HEI-OC1 cell ototoxicity. [ABSTRACT FROM AUTHOR]

The present study is aimed at investigating the molecular mechanism of C1q/TNF-related protein 9 (CTRP9) and providing a new perspective in arteriovenous shunt-induced pulmonary arterial hypertension (PAH). PAH was established by an arteriovenous shunt placement performed in rats. Adenovirus(Ad)-CTRP9 and Ad-green fluorescent protein viral particles were injected into the rats through the tail vein. Following 12 weeks, the mean pulmonary arterial pressure (mPAP) and right ventricular systolic pressure (RVSP) were measured and morphological analysis was conducted to confirm the establishment of the PAH model. The systemic elevation of CTRP9 maintained pulmonary vascular homeostasis and protected the rats from dysfunctional and abnormal remodeling. CTRP9 attenuated the pulmonary vascular remodeling in the shunt group by decreasing the mPAP and RVSP, which was associated with suppressed inflammation, apoptosis, and extracellular matrix injury. In addition, CTRP9 dramatically increased the phosphorylation of AKT and p38-MAPK in the lung tissues of shunt-operated animals. These findings suggest a previously unrecognized effect of CTRP9 in pulmonary vascular homeostasis during PAH pathogenesis. [ABSTRACT FROM AUTHOR]

The internal curing method is effective in reducing the self-desiccation of concrete, and the amount of internal curing water (IC water) is greatly important to the shrinkage and strength of concrete. A method for calculating IC water of concrete with and without mineral admixture has been developed. The method is derived from Powers' model for the phase distribution of a hydrating cement paste. To verify the method, a series of autogenous shrinkage and compressive strength of concrete with and without super absorbent polymer (SAP) were evaluated compared with the method proposed previously. To explain the macro performance of hardened concrete, the nonevaporable water content and calcium hydroxide content measurement were utilized to evaluate the degree of hydration of cement pastes. And, mercury intrusion method and image analysis method were used to explore the pore structure in hardened cement pastes and air void characteristics in hardened concrete, respectively. Furthermore, the evolution process was also studied for the relative humidity inside the concrete. [ABSTRACT FROM AUTHOR]

For normal-hearing (NH) listeners, monaural factors, such as voice pitch cues, may play an important role in the segregation of speech signals in multitalker environments. However, cochlear implant (CI) users experience difficulties in segregating speech signals in multitalker environments in part due to the coarse spectral resolution. The present study examined how the vocal characteristics of the target and masking talkers influence listeners' ability to extract information from a target phrase in a multitalker environment. Speech recognition thresholds (SRTs) were measured with one, two, or four masker talkers for different combinations of target-masker vocal characteristics in 10 adult Mandarin-speaking NH listeners and 12 adult Mandarin-speaking CI users. The results showed that CI users performed significantly poorer than NH listeners in the presence of competing talkers. As the number of masker talkers increased, the mean SRTs significantly worsened from –22.0 dB to –5.2 dB for NH listeners but significantly improved from 5.9 dB to 2.8 dB for CI users. The results suggest that the flattened peaks and valleys with increased numbers of competing talkers may reduce NH listeners' ability to use dips in the spectral and temporal envelopes that allow for "glimpses" of the target speech. However, the flattened temporal envelope of the resultant masker signals may be less disruptive to the amplitude contour of the target speech, which is important for Mandarin-speaking CI users' lexical tone recognition. The amount of masking release was further estimated by comparing SRTs between the same-sex maskers and the different-sex maskers. There was a large amount of masking release in NH adults (12 dB) and a small but significant amount of masking release in CI adults (2 dB). These results suggest that adult CI users may significantly benefit from voice pitch differences between target and masker speech. [ABSTRACT FROM AUTHOR]

A new method has been developed to simultaneously determine 7 pyrethroid residues in tea brew using gas chromatography-mass spectrometry (GC-MS) combined with solid phase microextraction (SPME) with multiwalled carbon nanotubes (MWCNTs) coated fiber. The MWCNTs coated fiber of SPME was homemade by using stainless steel wire as coating carrier and polyacrylonitrile (PAN) solution as adhesive glue. Under the optimized conditions, a good linearity was shown for bifenthrin, fenpropathrin, permethrin, and cyfluthrin in 1–50 ng mL−1 and for cypermethrin, fenvalerate, and deltamethrin in 5–50 ng mL−1. The correlation coefficients were in the range of 0.9948–0.9999. The average recoveries of 7 pyrethroids were 94.2%–107.3% and the relative standard deviations (RSDs) were less than 15%. The detection limit of the method ranged from 0.12 to 1.65 ng mL−1. The tea brew samples made from some commercial tea samples were analyzed. Among them, bifenthrin, fenpropathrin, and permethrin were found. The results show that the method is rapid and sensitive and requires low organic reagent consumption, which can be well used for the detection of the pyrethroids in tea brew. [ABSTRACT FROM AUTHOR]

To detect the evolutional characteristics of pore structure in ore leaching process of ion-type rare earth, this paper analyzes the influence mechanism of ion exchange seepage action on the microstructure of orebody, and an experiment for remodeling rare earth saturated samples and ore leaching was designed. Using nuclear magnetic resonance technology obtains the pore structure T2 map of H2O and (NH4)2SO4 solution in the ore leaching process and inverts and reconstitutes the pore structure distribution image. The results of contrastive analysis experiments indicate that impact factors of the ore leaching process on the microstructure of rare earth orebodies include two aspects: solution seepage and ion exchange. The main factor of pore structure distribution is the ion exchange action, determined by a dual effect. The sole action of solution seepage leads to an increase in pore size, which means that pore size structure is changing from small and medium to macro. Ion exchange gives rise to the movement and restructuring of particles, which results in a decrease in pore sizes. The pore structure changes from loose to compact; in the entire ore leaching process, the ion exchange action advances in a layered shape along the direction of seepage, and the chemical replacement and physical seepage alternately impact the microstructure of the orebodies. [ABSTRACT FROM AUTHOR]

In clinical practice, the effectiveness of the rehabilitation therapy such as acupuncture combining conventional Western medicine (AG) on stroke people’s motor-related brain network and their behaviors has not been systematically studied. In the present study, seventeen adult ischemic patients were collected and divided into two groups: the conventional Western medicine treatment group (CG) and the AG. The neurological deficit scores (NDS) and resting-state functional MRI data were collected before and after treatment. Compared with the CG patients, AG patients exhibited a significant enhancement of the percent changes of NDS from pre- to posttreatment intervention. All patients showed significant changes of functional connectivity (FC) between the pair of cortical motor-related regions. After treatment, both patient groups showed a recovery of brain connectivity to the nearly normal level compared with the controls in these pairs. Moreover, a significant correlation between the percent changes of NDS and the pretreatment FC values of bilateral primary motor cortex (M1) in all patients was found. In conclusion, our results showed that AG therapy can be an effective means for ischemic stroke patients to recover their motor function ability. The FC strengths between bilateral M1 of stroke patients can predict stroke patients’ treatment outcome after rehabilitation therapy. [ABSTRACT FROM AUTHOR]

The human brain has an enormous capacity to adapt to a broad variety of environmental demands. Previous studies in the field of abacus training have shown that this training can induce specific changes in the brain. However, the neural mechanism underlying these changes remains elusive. Here, we reviewed the behavioral and imaging findings of comparisons between abacus experts and average control subjects and focused on changes in activation patterns and changes in brain structure. Finally, we noted the limitations and the future directions of this field. We concluded that although current studies have provided us with information about the mechanisms of abacus training, more research on abacus training is needed to understand its neural impact. [ABSTRACT FROM AUTHOR]

Exact (EX) and approximate (AP) calculations rely on distinct neural circuits. However, the training effect on the neural correlates of EX and AP calculations is largely unknown, especially for the AP calculation. Abacus-based mental calculation (AMC) is a particular arithmetic skill that can be acquired by long-term abacus training. The present study investigated whether and how the abacus training modulates the neural correlates of EX and AP calculations by functional magnetic resonance imaging (fMRI). Neural activations were measured in 20 abacus-trained and 19 nontrained Chinese children during AP and EX calculation tasks. Our results demonstrated that: (1) in nontrained children, similar neural regions were activated in both tasks, while the size of activated regions was larger in AP than those in the EX; (2) in abacus-trained children, no significant difference was found between these two tasks; (3) more visuospatial areas were activated in abacus-trained children under the EXtask compared to the nontrained. These results suggested that more visuospatial strategies were used by the nontrained children in the AP task compared to the EX; abacus-trained children adopted a similar strategy in both tasks; after long-term abacus training, children were more inclined to apply a visuospatial strategy during processing EX calculations. [ABSTRACT FROM AUTHOR]