Waveform-Controlled Terahertz Radiation from the Air Filament Produced by Few-Cycle Laser Pulses

Waveform-controlled Terahertz (THz) radiation is of great importance due to its potential application in THz sensing and coherent control of quantum systems. We demonstrated a novel scheme to generate waveform-controlled THz radiation from air plasma produced when carrier-envelope-phase (CEP) stabilized few-cycle laser pulses undergo filamentation in ambient air. We launched CEP-stabilized 10 fs-long (~ 1.7 optical cycles) laser pulses at 1.8 {\mu}m into air and found that the generated THz waveform can be controlled by varying the filament length and the CEP of driving laser pulses. Calculations using the photocurrent model and including the propagation effects well reproduce the experimental results, and the origins of various phase shifts in the filament are elucidated.Comment: 5pages, 5 figure

Biologically Inspired Design of Context-Aware Smart Products

The rapid development of information and communication technologies (ICTs) and cyber–physical sys-tems (CPSs) has paved the way for the increasing popularity of smart products. Context-awareness isan important facet of product smartness. Unlike artifacts, various bio-systems are naturally characterizedby their extraordinary context-awareness. Biologically inspired design (BID) is one of the most commonlyemployed design strategies. However, few studies have examined the BID of context-aware smart prod-ucts to date. This paper presents a structured design framework to support the BID of context-awaresmart products. The meaning of context-awareness is defined from the perspective of product design.The framework is developed based on the theoretical foundations of the situated function–behavior–structure ontology. A structured design process is prescribed to leverage various biological inspirationsin order to support different conceptual design activities, such as problem formulation, structure refor-mulation, behavior reformulation, and function reformulation. Some existing design methods and emerg-ing design tools are incorporated into the framework. A case study is presented to showcase how thisframework can be followed to redesign a robot vacuum cleaner and make it more context-aware.Ó2019 THE AUTHORS. Published by Elsevier LTD on behalf of Chinese Academy of Engineering andHigher Education Press Limited Company. This is an open access article under the CC BY-NC-ND licens

Cancer type-specific modulation of mitochondrial haplogroups in breast, colorectal and thyroid cancer

<p>Abstract</p> <p>Background</p> <p>Mitochondrial DNA (mtDNA) haplogroups and single nucleotide polymorphisms (mtSNP) have been shown to play a role in various human conditions including aging and some neurodegenerative diseases, metabolic diseases and cancer.</p> <p>Methods</p> <p>To investigate whether mtDNA haplogroups contribute to the occurrence of cancer in a specific Chinese population, we have carried out a comprehensive case-control study of mtDNA from large cohorts of patients with three common cancer types, namely, colorectal cancer (n = 108), thyroid cancer (n = 100) and breast cancer (n = 104), in Wenzhou, a southern Chinese city in the Zhejiang Province.</p> <p>Results</p> <p>We found that patients with mtDNA haplogroup M exhibited an increased risk of breast cancer occurrence [OR = 1.77; 95% CI (1.03-3.07); P = 0.040], and that this risk was even more pronounced in a sub-haplogroup of M, D5 [OR = 3.11; 95%CI (1.07-9.06); p = 0.030]. In spite of this, in patients with breast cancer, haplogroup M was decreased in the metastatic group. On the other hand, our results also showed that haplogroup D4a was associated with an increased risk of thyroid cancer [OR = 3.00; 95%CI (1.09-8.29); p = 0.028]. However, no significant correlation has been detected between any mtDNA haplogroups and colorectal cancer occurrence.</p> <p>Conclusion</p> <p>Our investigation indicates that mitochondrial haplogroups could have a tissue-specific, population-specific and stage-specific role in modulating cancer development.</p

Single femoral artery access is safe and feasible during transcatheter aortic valve replacement: a propensity score matched analysis

BackgroundTranscatheter aortic valve replacement (TAVR) potentially may be significantly simplified by using the single artery access (SA) technique, which does not require a secondary artery access. Nevertheless, the safety and efficacy of this technique remains unclear. Our goal was to determine if single artery access TAVR (without upgrading the sheath size) is a feasible, minimally invasive procedure.MethodsPatients with symptomatic severe aortic stenosis who underwent TAVR via the femoral artery were consecutively enrolled in this study. Eligible individuals were divided into 2 groups: the SA group and the dual artery access (DA) group. The primary end point was device success (defined by the valve academic research consortium 3, VARC 3). A 6-month follow-up and propensity score matching analyses were performed.ResultsAfter propensity score matching analysis, a total of 130 patients were included: 65 in the SA group and 65 in the DA group. The SA procedure achieved similar device success (95.4% vs. 87.7%; P = 0.115) compared with the DA procedure. The SA procedure shortened the operating time (102 min vs. 125 min; P = 0.001) but did not increase the x-ray time or dose. Both a 20 Fr and a 22 Fr sheath (without upgrading the sheath size) could be used for the SA procedure. There was no major vascular complication occurred in both groups. The incidence of minor main vascular and access complications in the SA group was comparable to those of the DA procedure (0.0% vs. 3.1%; P = 0.156).ConclusionsThe SA access procedure is a promising minimally invasive TAVR technique with a low incidence of vascular complications and a high incidence of device success. It is safe and possibly applicable in all TAVR procedures

Embankment seismic fragility assessment: A case study on Xi'an-Baoji expressway (China).

Although embankment seismic damages are very complex, there has been little seismic fragility research yet. Researches on seismic fragility of bridges, dams and reinforced concrete (RC) structures have achieved fruitful results, which can provide references for embankment seismic fragility assessment. Meanwhile, the influencing degrees of retaining structures, such as retaining walls on the embankment seismic performances are still unclear. The K1025+470 embankment of the Xi'an-Baoji expressway was selected as the research object, and the finite difference models of the embankment fill-soil foundation system and embankment fill-soil foundation-retaining wall system were established. The ground-motion records for Incremental Dynamic Analysis (IDA) were selected and the dynamic response analysis were conducted. Probabilistic Seismic Demand Analysis (PSDA) was used to deal with the IDA results and the seismic fragility curves were generated. Based on the assessment results, the influences of the retaining wall on the embankment seismic fragility were further verified. The research results show that regardless of which seismic damage parameter is considered or the presence or absence of the retaining wall, larger PGAs always correspond to higher probabilities of each seismic damage grade. Seismic damages to the embankment fill-soil foundation-retaining wall system are always lower than those of the embankment fill-soil foundation system under the same PGA actions, thus, the retaining wall can decrease the embankment seismic fragility significantly

Efficient expression and primary purification of 6-his tagged human Fas ligand in Dictyostelium discoideum

Human Fas ligand (hFasL) is a member of the tumor necrosis factor (TNF) family with many medical interests. To produce this protein efficiently, an improved vector which could express the recombinant hFasL protein with a 6-his tag at its C-terminal was constructed. The new vector was transformed into Dictyostelium discoideum AX3 which then produced 157 mu g hFasL l(-1) stop. Using one-step Ni-affinity chromatography, it was purified with a recovery of 92% and purity of 91%

Production, purification and cytotoxity of soluble human Fas ligand expressed by Escherichia coli and Dictyostelium discoideum

Human Fas ligancl (hFasL) is a type II membrane protein that induces apoptosis in the Fas-bearing cells. Its special biological activity has the potential for the therapeutic use as an anti-cancer agent directed at enhancing apoptosis in tumor cells. In this study Escherichia coli and eukaryotic Dictyostelium discoideum were used to produce a soluble form of hFasL in large amounts. An expression vector for hFasL production in E. coli was constructed based on plasmid pET32a(+). By cultivation of the hFasL-producing E. coli clone on LB medium and induction with IPTG, a hFasL concentration of 1.0 mg L-1 was achieved. D. discoideum strain AX3-hFasL-H was cultured in a conventional stirred bioreactor on an improved synthetic medium using a simple fed-batch strategy, and cell densities of up to 8.3 x 10(7) cells/mL and a maximum hFasL concentration of 420 mu g/L were obtained. Using Ni-NTA affinity chromatography purification, two kinds of recombinant hFasLs from E. coli and D. discoideum were purified with a purity of 94% and 90%, respectively. They showed similar biological activities in inducing apoptosis in Fas-expressing cells. (C) 2012 Elsevier B.V. All rights reserved.Program for New Century Excellent Talents in Fujian Province, PR China; National Natural Science Foundation of China [31071488, 20736008, 20928006