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The objective of this work is to carry out a thorough investigation on the optimization of the vehicle suspension system based on vibration and noise management. First, a transfer path analysis is proposed to clarify the weight coefficient of vehicle's suspension system reaction optimization, resulting in an improved suspension system in reaction to optimization objective function to avoid the limitations of traditional vehicle suspension system's reaction optimization and ensure that the natural frequency and decoupling rate objectives will not deteriorated. To complete the optimization of the vehicle suspension system based on vibration and noise management, the variable step size algorithm is utilized to enhance the filtered least mean square method while at the same time, the adaptive algorithm is improved. The strategy put forward in this research has been shown to have a good effect on the optimization of the vehicle's suspension system through experimental verification. This method can effectively enhance the vehicle's overall comfort and stability while increasing operating safety. It is anticipated that it will serve as a valuable resource for future studies in this area. [ABSTRACT FROM AUTHOR]

Embryogenesis is the critical developmental phase in the life cycle of flowering plants, which starts with the double fertilization. In the model plant Arabidopsis, since the single-celled zygote follows a defined cell division and differentiation pattern to form a mature embryo, Arabidopsis embryogenesis is an ideal system for research of the cell fate determination and cell–cell communication. Here, we present an efficient semi–in vivo zygotic embryogenesis system in Arabidopsisvia ovule culture. To achieve highly efficient embryogenesis, some key factors were carefully investigated. B5 medium supplemented with 10% sucrose was suitable for embryogenesis. After 5 d of culture, about 43% of all ovules could develop from the zygote stage to the globular embryo stage. By applying the system, we found that exogenous spermidine was not required for embryo development in ovules, and dicyclohexylamine, an inhibitor of spermidine synthase, significantly inhibited embryogenesis, and the inhibiting effect could be rescued by exogenous spermidine. Also, we tested the development of the ovules at 1-celled embryo stage after laser microdissection of apical cell, confirming it a useful system for experimental embryological investigations. [ABSTRACT FROM AUTHOR]

Acellular dermal matrix (ADM) can be used as a new membrane substitute for repairing mucosal defects. The objective of this study is to explore the effectiveness of xenogenic acellular dermal matrix (xeno-ADM) in hypopharynx reconstruction. A total of 40 patients were treated with this surgical method to reconstruct hypopharynx in our department between February 2011 and October 2012. Patients were diagnosed had hypopharyngeal cancer located at lateral and/or postpharyngeal wall. The mucosal defect size after hypopharyngeal resection was 3 × 4 cm-6 × 7 cm, and was repaired by xeno-ADM. Patients were followed up for 11-36 months. 4 patients got infected, and two developed into pharyngeal fistula. Patients regained eating function 2-5 weeks after surgery. No membrane was removed; no severe stenosis of hypopharynx was observed. All patients were successfully decannulated. The overall 3-year survival rate is 67.5 %; the 3-year disease-free rate is 47.5 %. Reconstruction of hypopharynx by xeno-ADM is proved to be a simple, safe and effective method with fewer complications. [ABSTRACT FROM AUTHOR]

Key message: We found that protein trafficking between apical and basal cell can be unidirectional, which reveals the different roles of the two cells in the cell-to-cell communication between them during early embryogenesis. Abstract: In most angiosperm species, asymmetric zygote division results in an apical cell and a basal cell that have distinct cell fates. Much has been speculated about possible communication between these cell types in relation to their cell fate determination. Here, we report on the use of photoactivatable green fluorescent protein (PA-GFP) in tobacco to trace intercellular communication between apical and basal cells during early embryogenesis. We found that PA-GFP was transported between apical and basal cells of a two-celled proembryo, and that protein trafficking was unidirectional toward the apical cell, highlighting different cell communication roles. Further ultrastructural analysis showed numerous plasmodesmata in the walls connecting the apical and basal cells, which may provide channels for protein trafficking. Our data show a possible unique method of cell-to-cell communication between apical and basal cells during early embryogenesis. [ABSTRACT FROM AUTHOR]

Background: Parent-of-origin gene expression and its role in seed development have drown a great attention in recent years. Genome-wide analysis has identified hundreds of candidate imprinted genes, a major type of parent-of-origin genes, in rice hybrid endosperms at the stage of 5 days after pollination (dap). However, the expression of these genes in early endosperm have been never confirmed due to technique limitations and the behavior of the imprinted genes in different rice hybridizations are still largely unknown. Results: Here, based on our elaborate technique established previously, the expression patterns of PcG genes in the early stages of endosperm development (within 3 dap), were comprehensively analyzed. We revealed that the free nucleus stage of endosperm development is critical for parent-of-origin gene analysis. The expression of the imprinted genes are highly dynamic, likely corresponding to the critical developmental events during this period. Hybridizations between Oryza sativa japonica and indica showed that the expression patterns of the same imprinted gene could be varied by crossing with different parental cultivars, indicative of their parent-dependent character. There are strong alleles that often showed predominant expression over other alleles regardless of the parental origin, which provides a possible explanation for the cultivar-dependent predominant phenotype in crop hybridizations. In addition, we found that the transcripts of the same gene behave differently, with imprinting or non-imprinting patterns, suggesting the existence of not only imprinted and non-imprinted genes but also imprinted or non-imprinted transcripts, which reveals new aspects of the genomic imprinting. Conclusions: These findings on the characters of parent-of-origin genes shed light on the understanding the real role of gene imprinting in endosperm development. [ABSTRACT FROM AUTHOR]

Brassica napus is one of the most important oilseed crops in the world and Plasmodiophora brassicae is a serious threat causing yield reduction. CRb and PbBa8.1 resistance genes are known to be highly effective against P. brassicae race 4. Here, we combined two clubroot resistance (CR) genes through marker-assisted selection (MAS) and developed CR homozygous lines. The CR parental and pyramided lines were crossed with genetically male sterile (GMS) plants to generate heterozygous lines. In order to confirm their differences on resistance, the parental and generated lines were inoculated with 9 P. brassicae field isolates in the greenhouse and resistant test also evaluated in different naturally infested fields. The CR pyramiding lines exhibited high levels of resistance to the most isolates than line containing any single resistance gene; comparatively, the homozygous lines demonstrated a higher resistance than the heterozygous. The genetic variation among P. brassicae isolates was analyzed through simple sequence repeat (SSR) marker and significant divergences were recorded among the 9 tested field isolates and the result was consistent with data acquired from the greenhouse and natural field experiments. This study will certainly provide a novel molecular strategy for the breeding of the durable CR B. napus varieties in future breeding programs. [ABSTRACT FROM AUTHOR]

The aim of this study was to explore xenogeneic acellular dermal matrix (ADM) in combination with pectoralis major myocutaneous flap in hypopharynx and cervical esophagus reconstruction. A total of five patients were treated with this surgical method to reconstruct hypopharynx and cervical esophagus in Second Xiangya Hospital between January 2012 and April 2013. Four of them had hypopharyngeal carcinoma with laryngeal and cervical esophageal invasion, while the fifth patient with hypopharyngeal cancer had developed scars and atresia after postoperative radiotherapy. The defect length after hypopharyngeal and cervical esophageal resection was 6-8 cm, and was repaired by a combination of ADM and pectoralis major myocutaneous flap by our team. Interestingly, the four patients had primary healing and regained their eating function about 2-3 weeks after surgery, the fifth individual suffered from pharyngeal fistula, but recovered after dressing change about 2 months. Postoperative esophageal barium meals revealed that the pharynx and esophagus were unobstructed in all five patients. Xenogeneic ADM in combination with pectoralis major myocutaneous flap for hypopharynx and cervical esophagus reconstruction is a simple, safe and effective method with fewer complications. Nevertheless, according to the defect length of the cervical esophagus, the patients need to strictly follow the medical advice. [ABSTRACT FROM AUTHOR]

The aim of our study is to present our experience in the diagnosis and treatment of patients with carotid artery rupture (CAR) due to foreign body ingestion. A total of nine admissions with CAR due to foreign body ingestion were recorded in Second Xiangya Hospital between 1969 and 2011. The carotid artery was sutured with muscle flap coverage in six cases, ligated in three cases. We retrospectively compared different surgical procedures of the patients and their clinical outcomes. Results show that CAR was found in all of these nine cases in imaging examinations or surgery. Among these six patients treated by suture of the carotid artery, five patients had a complete recovery without any complications, one patient underwent common carotid artery (CCA) ligation after suture surgery, but finally died of massive hemorrhage due to uncontrollable infection with carotid artery erosion. Among these three patients treated only by CCA ligation, one patient had no complications, one patient had hemiplegia, and one patient died of severe cerebral edema. Hence, timely diagnosis and open surgery are important for the patients of CAR due to foreign body ingestion. Suture of the carotid artery with muscle flap coverage is a better method compared with ligation of the carotid artery in the treatment of CAR. [ABSTRACT FROM AUTHOR]

The yield of rapeseed is directly and indirectly influenced by silique-related traits, the genetic dissection, and improvement of the silique-related traits are thus the most important research project in rapeseed. Seven silique-related traits, including seed number per silique (SPS), silique length (SL), silique width (SW), silique thickness (ST), silique volume (SV), silique density (SD), and thousand seed weight (TSW) were further analyzed through quantitative trait locus (QTL) mapping based on a high-density genetic linkage map in KN population. A total of 273 identified QTLs were integrated into 230 consensus QTLs, in which 84.78% of consensus QTLs were considered to be environment-specific QTLs and 15.22% of consensus QTLs were considered to be environmentally stable expression QTLs. Two major QTLs, including cqSW.C6-5 for SW and cqSPS.C6-3 for SPS were identified on C06. According to QTLs integrated from different silique traits, 48 unique QTLs were identified with pleiotropy that involved in 2–5 silique-related traits. In addition, 185 epistatic locus pairs were identified with the PV ranging from 0.96 to 15.98%. QTL comparison were made between the KN population and other mapping populations, a total of 164 QTLs for silique-related traits (48 for SPS, 31 for SL, 7 for SD, and 78 for TSW) from nine previously reported researches were aligned to the Brassica napus reference genome, in which 23 QTLs were considered as new QTLs (8 for SD, 4 for SL, 7 for SPS, 4 for TSW). More importantly, cqSPS.C6-3 for SPS might be a novel major QTL. Furthermore, 82 candidate genes in B. napus corresponding to 48 candidate genes in Arabidopsis thaliana were identified, which were involved in transcription factors, enzymes, protein structure units, phytohormone response factors, and transporters, etc. These findings not only provided more comprehensive insights into the genetic basis for silique-related traits but also new cues for improving silique and increasing seed yield in B. napus. [ABSTRACT FROM AUTHOR]