Mechanical Properties of Low-Performance Concrete (LPC) and Shear Capacity of Old Unreinforced LPC Squat Walls

Low-performance concrete (LPC) is characterized by its low strength and commonly by the presence of large aggregates. This type of concrete was used for construction of load carrying, commonly unreinforced walls in old buildings. The resistance of these buildings with LPC squat walls (of relatively low height-to-length ratio), to in plane horizontal loads, was experimentally investigated in this study. The low compressive strength of these walls, well below that of standard concrete, requires estimation of the relation between the actual LPC compressive strength and its tensile strength, and identification of their failure mode and corresponding shear capacity when subjected to in plane horizontal loads. In this study, compressive and splitting tensile strengths of authentic LPC specimens were measured, and based on them, a relation between the compressive and tensile strengths is proposed. Then, diagonal compression tests were performed on authentic LPC specimens, as well as specimens made of standard concrete. These tests yielded the expected mode of failure of vertical cracking and their analysis shows that their shear capacity needs to be evaluated based on their tensile strength (rather than the flexural shear capacity of unreinforced concrete beams). Thus, the load-bearing (both horizontal and gravitational) capacity to prevent diagonal tension failure of an unreinforced LPC wall can be evaluated by comparing the LPC tensile strength to the major principal stress caused by the load. Assessment of the tensile strength can be based on the relation between the compressive and tensile strengths proposed in this work.     

Selective influence of the menstrual cycle on perception of stimuli with reproductive significance: an event-related potential study

In this study, we examined changes in the event-related potential (ERP) to stimuli with and without reproductive significance occurring during the menstrual cycle. Eleven spontaneously cycling women were tested during three menstrual phases (menses, ovulatory phase, luteal phase) differing in plasma concentrations of gonadal hormones. ERPs were recorded while subjects were presented with slides showing pictures from four different stimulus categories (sexual stimuli, babies, people occupied with body care, ordinary people). Slides were presented randomly in the context of two tasks, requiring either affective processing (i.e., to judge the emotional content of a slide as positive, neutral, or negative) or structural processing (i.e., to estimate the number of parallel thin lines inserted in each picture). Menstrual phase primarily affected a late positive component (LPC) peaking 550-600 ms poststimulus. The effects were as follows: (i) During the ovulatory phase, amplitude of the LPC to sexual stimuli was larger than that evoked by the other stimulus categories. (ii) This relationship was not apparent during the other menstrual phases or (iii) during the ovulatory phase when the task required structural processing. The ovulatory increase in LPC positivity to sexual stimuli suggests a greater valence of these stimuli during a phase of increased sexual desire. The data indicate a specific effect of the menstrual cycle on the processing of sexual stimuli that increases with deeper emotional processing.     

HPLC-ELSD测定酒石酸长春瑞滨脂质体注射液中两降解物质

目的：建立HPLC-ELSD法测定酒石酸长春瑞滨脂质体注射液中两降解物质：磷脂酰胆碱（LPC）、磷脂酰乙醇胺（LPE）的含量。方法：采用Kromasil 100-5C4柱（250 mm×4.6 mm,5μm）,以水为流动相A,以甲醇（含0.10%二乙胺）为流动相B,梯度洗脱;柱温：40℃,流速为1.0 mL·min-1,蒸发光散射检测器,检测器漂移管温度：50℃,气体流量：2.0 L·min-1。结果：酒石酸长春瑞滨脂质体注射液中LPC与LPE能很好地分离检出,其线性浓度范围分别为：0.02~0.30 mg·mL-1（r=0.9997）、0.01~0.04 mg·mL-1（r=0.9994）,呈良好的线性关系,LPC 3种浓度平均加样回收率分别为99.9%、100.3%、98.9%。 RSD%分别为2.2%、0.5%、1.2%;LPE 3种浓度平均加样回收率分别为97.9%、96.6%、98.5%,RSD%分别为1.5%、0.7%、1.0%。结论：该方法简单、准确、重复性好,可用于本品中降解物质LPC和LPE的质量控制。     

The faces you remember: caricaturing shape facilitates brain processes reflecting the acquisition of new face representations

We report two experiments on the influence of spatial caricaturing on face learning and recognition. In the learning phase of Experiment 1, participants learned unfamiliar faces, half of which were caricatured at an exaggeration level of 30%. During learning we found increased N170, N250 and LPC and decreased P200 for caricatures. At test we observed better generalization to non-identical exemplars for faces learned as caricatures. At test, N250 was larger for caricatures. In Experiment 2, using more and stronger levels of caricaturing (0% = veridical, 35% and 70%), we replicated and extended main findings of Experiment 1 and found a clear learning advantage for caricatures. ERP and performance effects were directly related to the level of caricaturing. Overall, the present results suggest that (i) distinctive shape information is particularly informative to form new face representations for unfamiliar faces, and (ii) this formation of new representations is reflected by an increase in occipito-temporal negativity that is most prominent in the time range of the P200 and N250 components.     

Event-related brain potentials of masked repetition and semantic priming while listening to sentences

We combined for the first time electrophysiological measures and masked priming technique in sentential context, by setting up a cross-modal masked priming paradigm involving the auditory presentation of sentences. ERPs were time-locked to an auditorily presented word that was preceded by a repeated, related or unrelated pattern masked prime. We registered a two-way N400-difference between unrelated and related/repeated primes, followed by a late positive component (LPC) for repetition priming. Related primes appear to facilitate the lexical-semantic processing of the target to the same extent repeated primes do (equally attenuated N400). Repetition priming exerts additional demands (LPC), possibly related to enhanced recollection or to the construction of a discourse representation. This evidences that the sentential context interacts with masked priming in two vital ways, differing from word list contexts, and paves the way for future studies on the mechanisms of lexical/semantic processes beyond the word level.     

High-density lipoprotein phospholipids interfere with dendritic cell Th1 functional maturation

Lipoproteins are both lipid carriers in the blood and regulators of essential biological processes. Several studies demonstrated that lipoproteins modified during pathological conditions could alter dendritic cell (DC) maturation. Here the immune function of non-pathological lipoproteins is addressed by analysing their impact on human DC maturation triggered by TLR ligands. Upon TLR4 stimulation, low- and high-density lipoproteins (LDL and HDL) strongly inhibited the ability of DC to induce a Th1 response of T cells, characterized by high levels of IFNγ secretion, whereas the effect of very low-density lipoprotein was subject to variations. HDL also inhibited the Th1 function of DC stimulated by TLR1/2 and TLR2/6 ligands. The phospholipid fraction from HDL retained the inhibitory activity of the lipoprotein. We identified the 1-palmitoyl-2-linoleyl-phosphatidylcholine (PLPC) as one active phospholipid that inhibited the Th1 function of mature DCs whereas the dipalmitoyl-phosphatidylcholine had no significant effect. The treatment of DC by PLPC, 24 h before TLR4 stimulation, resulted in reduced activation of NF-κB. This study shows that some HDL phospholipids have a direct immunoregulatory function, by modulating DC ability to activate a Th1 response of T cells.     

基于LPC2103的植入式心脏起搏器程控仪设计

本文介绍了一种植入式心脏起搏器程控仪的工作原理与系统构成,该程控仪以LPC2103为核心搭建系统电路,并进行系统软件的编写,通过无线耦合的数据传输方式,实现程控仪对植入式心脏起搏器的程控与遥测.     

Modulation of ongoing cognitive processes by emotionally intense words

Contrary to what occurs with negative pictures, negative words are, in general, not capable of interfering with performance in ongoing cognitive tasks in normal subjects. A probable explanation is the limited arousing power of linguistic material. Especially intense words (insults and compliments), neutral personal adjectives, and pseudowords were presented to 28 participants while they executed a lexical decision task. Insults were associated with the poorest performance in the task and compliments with the best. Amplitude of the late positive component of the event-related potentials, originating at parietal areas, was maximal in response to compliments and insults, but latencies were delayed in response to the latter. Results suggest that intense emotional words modulate ongoing cognitive processes through both bottom-up (attentional capture by insults) and top-down (facilitation of cognitive processing by arousing words) mechanisms.     

Mathematical anxiety effects on simple arithmetic processing efficiency: An event-related potential study

This study uses event-related brain potentials to investigate the difficulties that high math anxious individuals face when processing dramatically incorrect solutions to simple arithmetical problems. To this end, thirteen high math-anxious (HMA) and thirteen low math-anxious (LMA) individuals were presented with simple addition problems in a verification task. The proposed solution could be correct, incorrect but very close to the correct one (small-split), or dramatically incorrect (large-split). The two groups did not differ in mathematical ability or trait anxiety. We reproduced previous results for flawed scores suggesting HMA difficulties in processing large-split solutions. Moreover, large-split solutions elicited a late positive component (P600/P3b) which was more enhanced and delayed in the HMA group. Our study proposes that the pattern of flawed scores found by previous studies (and that we replicate) has to do with HMA individuals’difficulties in inhibiting an extended processing of irrelevant information (large-split solutions).