An experimental study of impact performance of RC piers with different reinforcement ratios

U ovom se ispitivanju za simuliranje sudara broda i stupa koristi najnapredniji domaći sustav ispitivanja na udar s vrlo visokim padom malja. Osnovni naglasak stavljen je na određivanje sila udara, pomaka i vremenskog razvoja deformacija za pet armiranobetonskih uzoraka stupova s različitim koeficijentima armiranja, isto kao i na analizu oštećenja betona te pojavu i širenje pukotina nakon udara. Dobiveni rezultati pokazuju da povećanje koeficijenta armiranja dovodi u opisanim uvjetima ispitivanja do određenog poboljšanja bočne otpornosti AB stupova na udar.The most advanced domestic super-high drop hammer impact test system was used in this study to simulate ship-piers collisions. The main focus of this study was to examine the impact forces, displacements, and strain time histories of five reinforced concrete pier specimens with different reinforcement ratios, and to analyse concrete damage and crack propagation and development after impact events. The results showed that, under this test conditions, an increase in reinforcement ratio can somewhat improve the lateral impact resistance of reinforced concrete piers

Inhibition of N-Methyl-D-aspartate-induced Retinal Neuronal Death by Polyarginine Peptides Is Linked to the Attenuation of Stress-induced Hyperpolarization of the Inner Mitochondrial Membrane Potential

It is widely accepted that overactivation of NMDA receptors, resulting in calcium overload and consequent mitochondrial dysfunction in retinal ganglion neurons, plays a significant role in promoting neurodegenerative disorders such as glaucoma. Calcium has been shown to initiate a transient hyperpolarization of the mitochondrial membrane potential triggering a burst of reactive oxygen species leading to apoptosis. Strategies that enhance cell survival signaling pathways aimed at preventing this adverse hyperpolarization of the mitochondrial membrane potential may provide a novel therapeutic intervention in retinal disease. In the retina, brain-derived neurotrophic factor has been shown to be neuroprotective, and our group previously reported a PSD-95/PDZ-binding cyclic peptide (CN2097) that augments brain-derived neurotrophic factor-induced pro-survival signaling. Here, we examined the neuroprotective properties of CN2097 using an established retinal in vivo NMDA toxicity model. CN2097 completely attenuated NMDA-induced caspase 3-dependent and -independent cell death and PARP-1 activation pathways, blocked necrosis, and fully prevented the loss of long term ganglion cell viability. Although neuroprotection was partially dependent upon CN2097 binding to the PDZ domain of PSD-95, our results show that the polyarginine-rich transport moiety C-R(7), linked to the PDZ-PSD-95-binding cyclic peptide, was sufficient to mediate short and long term protection via a mitochondrial targeting mechanism. C-R(7) localized to mitochondria and was found to reduce mitochondrial respiration, mitochondrial membrane hyperpolarization, and the generation of reactive oxygen species, promoting survival of retinal neurons

The regulation of three new members of the cytochrome P450 CYP6 family and their promoters in the cotton aphid Aphis gossypii by plant allelochemicals

BACKGROUND: The expression of P450 genes in insects can be induced by plant allelochemicals. To understand the induction mechanisms, we measured the expression profiles of three P450 genes and their promoter activities under the induction of plant allelochemicals. RESULTS: The inducible expression of CYP6CY19 was the highest among three genes, followed by those of CYP6CY22 and CYP6DA1. The regions from −687 to +586bp of CYP6DA1, from−666 to +140bp of CYP6CY19 and from −530 to +218bp of CYP6CY22 were essential for basal transcriptional activity. The cis-elements for plant allelochemicals induction were identified between −193 and +56bp of CYP6DA1, between −157 and +140bp of CYP6CY19 and between −108 and +218bp of CYP6CY22. These promoter regions were found to contain a potential arylhydrocarbon receptor element binding site with a conservative sequence motif 5′-C/TAC/ANCA/CA-3′. All these four plant allelochemicals were able to induce the expression of these P450 genes. Tannic acid had a better inductive effect than other three plant allelochemicals. CONCLUSIONS: Our study identified the plant allelochemical responsive cis-elements. This provides further research targets aimed at understanding the regulatory mechanisms of P450 genes expression and their interactions with plant allelochemicals in insect pests

Functional Refinement in the Projection from Ventral Cochlear Nucleus to Lateral Superior Olive Precedes Hearing Onset in Rat

Principal neurons of the lateral superior olive (LSO) compute the interaural intensity differences necessary for localizing high-frequency sounds. To perform this computation, the LSO requires precisely tuned, converging excitatory and inhibitory inputs that are driven by the two ears and that are matched for stimulus frequency. In rodents, the inhibitory inputs, which arise from the medial nucleus of the trapezoid body (MNTB), undergo extensive functional refinement during the first postnatal week. Similar functional refinement of the ascending excitatory pathway, which arises in the anteroventral cochlear nucleus (AVCN), has been assumed but has not been well studied. Using whole-cell voltage clamp in acute brainstem slices of neonatal rats, we examined developmental changes in input strength and pre- and post-synaptic properties of the VCN-LSO pathway. A key question was whether functional refinement in one of the two major input pathways might precede and then guide refinement in the opposite pathway. We find that elimination and strengthening of VCN inputs to the LSO occurs over a similar period to that seen for the ascending inhibitory (MNTB-LSO) pathway. During this period, the fractional contribution provided by NMDA receptors (NMDARs) declines while the contribution from AMPA receptors (AMPARs) increases. In the NMDAR-mediated response, GluN2B-containing NMDARs predominate in the first postnatal week and decline sharply thereafter. Finally, the progressive decrease in paired-pulse depression between birth and hearing onset allows these synapses to follow progressively higher frequencies. Our data are consistent with a model in which the excitatory and inhibitory projections to LSO are functionally refined in parallel during the first postnatal week, and they further suggest that GluN2B-containing NMDARs may mediate early refinement in the VCN-LSO pathway

Photoresponse diversity among the five types of intrinsically photosensitive retinal ganglion cells

Intrinsically photosensitive retinal ganglion cells (ipRGCs) mediate non‐image‐forming visual responses, including pupillary constriction, circadian photoentrainment and suppression of pineal melatonin secretion. Five morphological types of ipRGCs, M1–M5, have been identified in mice. In order to understand their functions better, we studied the photoresponses of all five cell types, by whole‐cell recording from fluorescently labelled ipRGCs visualized using multiphoton microscopy. All ipRGC types generated melanopsin‐based (‘intrinsic’) as well as synaptically driven (‘extrinsic’) light responses. The intrinsic photoresponses of M1 cells were lower threshold, higher amplitude and faster than those of M2–M5. The peak amplitudes of extrinsic light responses differed among the ipRGC types; however, the responses of all cell types had comparable thresholds, kinetics and waveforms, and all cells received rod input. While all five types exhibited inhibitory amacrine‐cell and excitatory bipolar‐cell inputs from the ‘on’ channel, M1 and M3 received additional ‘off’‐channel inhibition, possibly through their ‘off’‐sublamina dendrites. The M2–M5 ipRGCs had centre–surround‐organized receptive fields, implicating a capacity to detect spatial contrast. In contrast, the receptive fields of M1 cells lacked surround antagonism, which might be caused by the surround of the inhibitory input nullifying the surround of the excitatory input. All ipRGCs responded robustly to a wide range of motion speeds, and M1–M4 cells appeared tuned to different speeds, suggesting that they might analyse the speed of motion. Retrograde labelling revealed that M1–M4 cells project to the superior colliculus, suggesting that the contrast and motion information signalled by these cells could be used by this sensorimotor area to detect novel objects and motion in the visual field.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106709/1/tjp6045.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/106709/2/tjp6045-sup-0001-SuppMat.pd

Draft genome sequence of the mulberry tree Morus notabilis

Human utilization of the mulberry–silkworm interaction started at least 5,000 years ago and greatly influenced world history through the Silk Road. Complementing the silkworm genome sequence, here we describe the genome of a mulberry species Morus notabilis. In the 330-Mb genome assembly, we identify 128 Mb of repetitive sequences and 29,338 genes, 60.8% of which are supported by transcriptome sequencing. Mulberry gene sequences appear to evolve ~3 times faster than other Rosales, perhaps facilitating the species’ spread worldwide. The mulberry tree is among a few eudicots but several Rosales that have not preserved genome duplications in more than 100 million years; however, a neopolyploid series found in the mulberry tree and several others suggest that new duplications may confer benefits. Five predicted mulberry miRNAs are found in the haemolymph and silk glands of the silkworm, suggesting interactions at molecular levels in the plant–herbivore relationship. The identification and analyses of mulberry genes involved in diversifying selection, resistance and protease inhibitor expressed in the laticifers will accelerate the improvement of mulberry plants