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Green flash light (FG) and green countdown (GC) are the two most common signal formats applied in green-red transition that provides drivers additional alert before termination of green phase. Due to their importance and function in stop-pass decision-making process, proper use of them has become a critical issue to greatly improve the safety and efficiency of signalized intersections. Gradually e-bike riders have become more important commuters in China, however, the influence of FG or GC on them is not clear yet and need pay more attention to it. This study chooses two almost identical intersections to obtain highly accurate trajectory data of e-bike riders to study their decision-making behaviors under FG or GC. The e-bike riders’ behavior is classified into four categories and is to identify their stop-pass decision points using the acceleration trend. Two binary-logit models were built to predict the stop–pass decision behaviors for the different e-bike rider groups, explaining that the potential time to the stop-line is the dominant independent factor of the different behaviors of GC and FG. Furthermore empirical analysis of decision points indicated that GC provides the earlier stop-pass decision point and longer decision making duration on the one side while results in more complexity of decision making and greater risk of stop-line crossing than FG on the other side.

MicroRNA 22 (miR-22) was found in diverse cardiovascular diseases to have a role in regulating multiple cellular processes. However, the regulatory role of miR-22 in aortic dissection (AD) was still unclear. The miR-22 expression in human aorta was explored. A series of mimic, inhibitor, or small interfering RNA (siRNA) plasmids were delivered into vascular smooth muscle cells (VSMCs) to explore the effects of miR-22 and p38 mitogen-activated protein kinase α (p38MAPKα) in controlling VSMC apoptosis in vitro. In addition, a mouse AD model was established, and histopathologic analyses were performed to evaluate the regulatory effects of miR-22. Reduced miR-22 and increased apoptosis of VSMCs was seen in human AD aorta. Downregulation of miR-22 increased the apoptosis of VSMCs in vitro. Bioinformatics analyses revealed that p38MAPKα was a target of miR-22. Inhibiting p38MAPKα expression could reverse the apoptosis of VSMCs induced by miR-22 downregulation. Knockdown of miR-22 in the AD mouse model significantly promoted the development of AD. Our data underscore the importance of vascular remodeling and VSMC function in AD. miR-22 may represent a new therapeutic approach for AD by regulating the apoptosis of VSMCs through the MAPK signaling pathway., Graphical Abstract, This study indicates miR-22 may represent a new therapeutic approach for aortic dissection by regulating the apoptosis of VSMCs through the MAPK signaling pathway. The study provided a novel insight into the mechanism of AD and the innovative therapeutic strategies in the form of new targets for small molecule therapies.

Background Infectious aortic aneurysm, defined as a focal dilation of an infectious arterial wall, is an uncommon life-threatening disease. Compared with open surgery, endovascular repair yields acceptable clinical outcomes. However, residual tissue infection may increase the risk of secondary intervention. Here, we present a successful case of endovascular repair combined with staged drainage for the treatment of infectious aortic aneurysm. Case presentation A 58-year-old man presented to hospital with a 3-day history of lower back pain radiating to the back associated with fever. The dynamic imaging characteristics revealed rapid progress of infectious abdominal aortic aneurysm with negative blood culture. The patient underwent endovascular repair and salmonella enteritidis was identified through drain culture. Conclusions Endovascular procedure and staged drainage can be feasible and effective option in selected cases.

Supervised Pix2Pix and unsupervised Cycle-consistency are two modes that dominate the field of medical image-to-image translation. However, neither modes are ideal. The Pix2Pix mode has excellent performance. But it requires paired and well pixel-wise aligned images, which may not always be achievable due to respiratory motion or anatomy change between times that paired images are acquired. The Cycle-consistency mode is less stringent with training data and works well on unpaired or misaligned images. But its performance may not be optimal. In order to break the dilemma of the existing modes, we propose a new unsupervised mode called RegGAN for medical image-to-image translation. It is based on the theory of "loss-correction". In RegGAN, the misaligned target images are considered as noisy labels and the generator is trained with an additional registration network to fit the misaligned noise distribution adaptively. The goal is to search for the common optimal solution to both image-to-image translation and registration tasks. We incorporated RegGAN into a few state-of-the-art image-to-image translation methods and demonstrated that RegGAN could be easily combined with these methods to improve their performances. Such as a simple CycleGAN in our mode surpasses latest NICEGAN even though using less network parameters. Based on our results, RegGAN outperformed both Pix2Pix on aligned data and Cycle-consistency on misaligned or unpaired data. RegGAN is insensitive to noises which makes it a better choice for a wide range of scenarios, especially for medical image-to-image translation tasks in which well pixel-wise aligned data are not available

In the present study, we evaluated and compared the outcomes of transarterial embolization with those of percutaneous contrast-enhanced ultrasound-guided transabdominal sac embolization (PUSE) for type II endoleaks (T2ELs).A retrospective review was conducted of consecutive patients who had undergone T2EL embolization between January 2015 and December 2020 at our center. The cohort was divided into two groups according to the embolization approach: PUSE vs transarterial. Freedom from aneurysm growth, safety, immediate technical success, freedom from persistent T2ELs, and the repeat embolization rate were assessed.A total of 25 patients and 28 embolization procedures (PUSE, n = 16; transarterial embolization, n = 12) were examined. Both the fluoroscopic time (13.3 ± 3.2 minutes vs 35.0 ± 7.0 minutes; P .001) and the procedural time (84.9 ± 8.4 minutes vs 117.1 ± 14.8 minutes; P .001) were significantly shorter in the PUSE group than in the transarterial group. After the embolization procedure, the patients were followed up for a mean duration of 24.7 ± 14.9 months for the PUSE group and 35.9 ± 21.1 months for the transarterial group (P = .1323). Five patients in the transarterial group had undergone unsuccessful embolization, with success in 7 of the 12 patients in the transarterial group and all 16 patients in the PUSE group (P = .0081). Failure had resulted from failed transarterial access or a recurrent T2EL. Three of the five patients had undergone subsequent PUSE during follow-up. No patient in the PUSE group had experienced sac expansion compared with four patients in the transarterial group (P = .0242). Similarly, no patient in the PUSE group had developed a newly discovered T2EL vs four patients in the transarterial group (P = .0242). Thus, the outcomes were markedly better for the PUSE group than were those for the transarterial group. A major procedure-related complication (abdominal abscess) occurred in one patient in the transarterial group.PUSE is safe and effective for managing T2ELs. It yields better outcomes in terms of preventing aneurysm growth, decreasing the incidence of repeat embolization and complications, minimizing the recurrence of T2ELs, and reducing the fluoroscopic and procedural times. We, thus, regard it as the preferred approach for the management of T2ELs.

Objective: To explore the feasibility of endovascular reconstruction of aortic root including aortic valve, sinus of valsalva and ascending aorta by a single stent-graft, a novel valved stent-graft with two fenestrae for preserving the coronary arteries was designed and performed in-vitro on a pig heart based circulation simulating system. Methods: Pig hearts were harvested from 30 healthy adult female pigs weighing between 60-65 kilograms. Before sacrifice, all the pigs received aortic computed tomography angiography (CTA) examinations and morphologic parameters of aortic root were measured. Then we customized the valved stent-grafts according to the CTA measurements. After the pig heart was fixed on the special platform according to the original orientation and connected to the circulation system, the stent graft was delivered through transapical access and covered the segment from aortic annulus to proximal part of aortic arch under DSA (digital subtraction angiography) guidance. Then changes of coronary flow before and after the procedure and fenestration alignment with coronary ostia were analyzed. Results: The overall technical success rate was 100%. The valve functions tested by ultrasound were in good condition under 120 mmHg circulation pressure. The flow of left coronary artery (LCA) did not decrease, but increased after the stent-graft implantation (340 ± 2.06 mL/min versus 288 ± 5.29 mL/min, P < .05). Similarly, the flow of right coronary artery (RCA) also increased (392 ± 9.17 mL/min versus 348 ± 8.01 mL/min; P < .05). The final angiography confirmed that both coronary arteries were patent. When generally observed from outer wall of valsalva sinus, both RCA and LCA orifices were aligned with the fenestrae. In 4 cases, the autologous valve leaflets blocked nearly 20% of the LCA fenestra’s area, but the flow did not significantly decrease in these cases. Conclusion: Stimulated on a pig heart-based circulation simulation system, the one-piece valved-fenestrated stent graft with a branch could be delivered via the transapical access and deployed accurately, which achieved endovascular reconstruction of aortic valve, sinus of valsalva and ascending aorta while preserving the coronary artery perfusion by fenestrations. More in-vivo experiments on animal models are mandatory to further verify its efficacy and safety.

The main objective of this paper is to elucidate the effect of rotor end structures of a large-scale air-cooled turbo-generator on the flow rate distribution and fluid flow pattern in the rotor domain. A 350 MW fully air-cooled turbo-generator is taken as an example. Based on the original ventilation structure, two optimization schemes of adding wind deflectors and small fans to the end of the rotor are proposed. The finite volume method is used to solve the fluid field in the generator with different rotor end structures. The air volume distribution in each wind area of the generator is taken as the basis for checking the accuracy of the calculation. Under different schemes, the wind path direction, flow rate and fluid velocity distribution in the radial ventilation ducts, subslots and crescent slots of the rotor are compared and analyzed. The effects of these schemes on the overall flow rate distribution and the fluid parameter distribution characteristics in each rotor ventilation ducts are determined.

Purpose: To report the findings of an in vitro experiment to evaluate the quality of needle fenestrations dilated by different size balloons in various stent-grafts and to investigate the differences between gradual and rapid dilation. Materials and Methods: Fenestrations were made using an 18-G needle in 5 different polyester or expanded polytetrafluoroethylene (ePTFE) stent-grafts: Relay, Valiant, Hercules, TAG, and Ankura. Each stent-graft received 2 groups of fenestrations: one was followed by gradual sequential dilation (4-, 6-, 8-, and 10-mm balloons) and the other by rapid dilation (4- and 10-mm balloons). The pressure was increased to 10 atmospheres or until the balloon was fully inflated with no waist. Quantitative and qualitative evaluations, including fenestration diameter, area, shape, and margins were conducted using light microscopy and scanning electron microscopy. Results: Relay had the strongest resistance to dilation and Ankura the slightest. The maximum length and area of holes expanded as the balloon diameter increased. The fenestrations in polyester devices were mostly elliptical or slit-like, with limited tears but extensive fibers visible in the margin, while ePTFE stent-grafts showed larger fenestration areas with clearer margins. Ankura showed the best quality of fenestrations, which were always circular or square without fabric tears, while the holes in the TAG were square or elliptical but sometimes had a slit after large balloon dilation (≥6 mm). The Relay, Valiant, Hercules, and Ankura devices showed no difference in maximum diameter, fenestration area, or scores of shape and margin (p>0.05). Rapid dilation in the TAG increased the rate of uncontrolled fabric tear, resulting in a larger final diameter (12.90 vs 10.82 mm, p=0.047), smaller area (30.46 vs 41.09 mm2, p=0.028), worse shape (0.75 vs 1.20, p=0.268), and worse margin (0.40 vs 1.00, p=0.174). Though the decreased fenestration shape and margin scores did not reach statistical significance, the trend for decline was more obvious than with the other devices. Conclusion: Materials and structures of the stent-grafts determine the quality of fenestrations dilated by different size balloons. The use of sequential vs rapid balloon dilation is also crucial for fashioning high-quality fenestrations and should be selected judiciously.

Purpose: To evaluate the safety and efficacy of total endovascular repair with parallel stent-grafts for postoperative residual dissection thoracoabdominal aortic aneurysm (TAAA). Materials and Methods: A retrospective study was undertaken of 21 patients (mean age 64.0±12.5 years; 17 men) undergoing total endovascular therapy with parallel stent-grafts for postdissection TAAA after prior proximal repair between 2014 and 2016. The preoperative minimum true lumen diameter was 12.3±4.8 mm and the mean extent of dissection was 248.1±48.2 mm. Pre-, intra-, and postoperative medical records were reviewed to assess technical success, spinal cord ischemia, patency of target branch arteries, endoleak, and short-term outcomes of this approach. Results: Technical success was achieved in 17 of 21 patients owing to 4 type I endoleaks at the end of the procedures. A total of 70 branch arteries were revascularized and 14 celiac trunks were covered intentionally without reconstruction. Of 7 intraoperative endoleaks, 2 were managed intraoperatively and 5 (4 type I and 1 type II) disappeared spontaneously within 1 month. No spinal cord or abdominal organ or limb ischemia was observed. Mean follow-up was 16.2±6.1 months. No death or type I or III endoleak occurred during the follow-up; 2 type II endoleaks were observed. Nineteen of the 21 false lumens thrombosed, and the total aortic diameter decreased (57.3±8.4 to 55.3±7.4 mm, p

Background Endovascular repair has been used in selected ascending aortic dissection patients judged unfit for direct open surgery. However, the selective criteria and the results of endovascular repair of ascending aortic dissection, and the potential risk factors of adverse events were still obscure. The aim of this study was to summarize the published data linking endovascular therapy for ascending aortic dissection. Methods Studies reporting endovascular repair of ascending aortic dissections were identified by searching PubMed and Embase databases in accordance with preferred reporting items for systematic reviews and meta-analyses guidelines, and by reviewing the reference lists of retrieved articles. All available data were pooled and the subgroup analyses were conducted. Results A total of nine studies were identified according to the inclusion criteria. The overall technical success was 91.7%. The mean period of follow-up was 34.7 months. The early mortality within 30 days and late mortality during the follow-up were 10.3% and 19.0%, respectively. The incidence of endoleak was 14.3%. In the subgroup analysis, we found that female and oversizing >10% were risk factors of adverse events. Conclusions The pooled results suggested that endovascular repair of ascending aortic dissection was feasible, promising, and inspiring. The selection of endovascular therapy should be cautious based on preoperative evaluation. Application of different strategies for different ascending lesions should be considered. The dedicated endograft for ascending aorta is desperately needed before broader application of endovascular repair for ascending aortic pathologies can be achieved.

Mn-doped Cu3N films were deposited by cylindrical magnetron sputtering equipment on the common glass at room temperature. The incorporation of Mn can change the preferred growth orientation from Cu-rich plane (111) to N-rich plane (100) due to the improvement of nitridation of Cu. The shrinkage of the lattice and the X-ray photoelectron spectroscopy results reveal that Mn should replace Cu atoms in the lattice or be segregated in the grain boundaries. The thickness of Mn-doped film is smaller than that of the pure one due to the less physisorption of N species among the columnar grains. The mean grain size and the energy gap become larger with increasing Mn concentration to 2.2 at.% and then decrease when the concentration of Mn is higher than 2.2 at.%. Notably, weak doping of 1.5 at.% Mn successfully promotes the decomposed temperature by ∼50 °C. According to the results of XRD and SEM for Mn-doped films annealed in vacuum, a possible decomposed mechanism with increasing the annealing temperature is proposed.

Flower-like ZnO/rGO/Ag micro/nano-composites (MNCs) have been engineered by a one-step microwave technique using graphene oxide, AgNO3 and Zn(CH3COO)2 as raw materials without adding any external toxic reagent. This is a facile and rapid process requiring only low power microwave irradiation (120 W). Various characterization results showed that the flower-like ZnO/rGO/Ag MNCs consisted of a ZnO nanosheet and Ag nanoparticles and reduced graphene oxide (rGO) deposited on ZnO nanosheet surface. The composite shows an enhanced and faster ultraviolet and simulated daylight photocatalytic property, i.e. 92.73% and 70.43% degradation of methyl orange in 20 minutes as compared to the values of 70.91% and 60.82%, 55.48% and 50.61% by bare ZnO and rGO/ZnO, respectively. The enhanced photocatalytic property is attributed to an efficient charge transfer process from ZnO to both Ag and rGO. This method would be beneficial for synthesizing efficient ZnO-based ternary photocatalysts with a combination of metal and rGO.

In the creation of a smart future information society, Internet of Things (IoT) and Content Centric Networking (CCN) break two key barriers for both the front-end sensing and back-end networking. However, we still observe the missing piece of the research that dominates the current networking traffic control and system management, e.g., lacking of the knowledge penetrated into both sensing and networking to glue them holistically. In this paper, we envision to leverage emerging machine learning or deep learning techniques to create aspects of knowledge for facilitating the designs. In particular, we can extract knowledge from collected data to facilitate reduced data volume, enhanced system intelligence and interactivity, improved service quality, communication with better controllability and lower cost. We name such a knowledge-oriented traffic control and networking management paradigm as the Knowledge Centric Networking (KCN). This paper presents KCN rationale, KCN benefits, related works and research opportunities.

G18CrMo2-6 steel is one kind of low alloy CrMo steel with ferrite/bainite phase constituent. It is widely adopted in the large casting parts of pressure vessels. This paper aims at investigating evolution of G18CrMo2-6 steel microstructure, tensile strength and impact toughness during the tempering (680 °C). The tempered microstructure characterization shows that the tempering time mainly affects the precipitation of three kinds of carbides, naming MC, M 3 C and M 23 C 6 . Both tensile strength and impact toughness do not obey the monotonic evolution with the tempering time but the complex changes. The shift of mechanical properties results from the interaction among matrix phases and the evolution of three different kinds of carbides. The softening of matrix due to the dislocation recovery and the decrease of the amout of carbon and other alloy elements in matrix lattice due to the precipitation of M 23 C 6 cause the decreasing tensile strength for the whole tempering except for that an increase during the short-term tempering controlled by the precipitation of MC and the spheroidization and refinement of M 3 C carbide. On the other hand, both the softening of matrix and the spheroidization and refinement of M 3 C carbide are responsible for the increasing impact toughness. However, the precipitation and coarsening of M 23 C 6 at ferrite grain boundaries during long-term tempering results in the sharp deterioration of impact toughness. It attributes to the larger grain boundary carbides result in the lower critical fracture stress of a carbide-ferrite interface.

Background: Stability of plaque has been implicated as risk factor for stroke. Serum cortisol regulates lipoprotein metabolism and immune response, contributing to plaque stability in atherosclerosis. However, the relationship between serum cortisol and stability of carotid plaque has not been well characterized. We conducted a serology analysis to identify the relationship between serum cortisol and carotid plaque stability. Methods: Between May 2013 to October 2015, 73 patients with carotid stenosis patients undergoing carotid endarterectomy (CEA) were enrolled in our study. Serum cortisol was analyzed at 8:00 AM in the morning before surgery via liquid chromatography tandem mass spectrometry. According to the classification made by the American Heart Association, hematoxylin-and-eosin staining was performed to divide these patients into either a stable or unstable group, according to the morphology of fibrous cap, lipid core and intima layer. A curve fitting method was used to identify the relationship between preoperative serum cortisol and stability of carotid plaque. Univariate and multivariate logistic regression analysis were used to identify carotid plaque stability-associated serum cortisol. Results: Curve fitting’s result represents a U-shape characteristic. A total of 314.92 and 395.23 nmol/L were considered as the cut point for preoperative serum cortisol when trisected the patients. When adjusted for degree of stenosis, hyperlipemia, smoking and low-density lipoprotein (LDL), univariate and multivariate logistic regression analysis’ results demonstrated that preoperative serum cortisol can significantly affect carotid plaque stability. The odds ratio values in multivariate logistic regression analysis for C reactive protein (CRP), white blood cell (WBC), interleukin-6 (IL-6) and preoperative serum cortisol level were 7.67 and 20.86 respectively. Conclusions: Preoperative serum cortisol was associated with stability of carotid plaque in patients undergoing CEA. Low or high levels of preoperative serum cortisol might be an adverse factor for carotid plaque stability.

The data center bridging (DCB) protocols enable Ethernet to become the leading unified fabric for a converged data center. As a part of DCB, priority flow control (PFC) is a control mechanism that provides the losslessness feature required by certain applications such as Fibre Channel over Ethernet. Quantized congestion notification (QCN) is also a DCB protocol and provides congestion control functionality to complement PFC. However, in today's practical data center networks, QCN is not feasible and PFC is not efficient against congestion. We propose a new link layer mechanism called congestion aware priority flow control (CaPFC) that equips PFC with better congestion control capability in the absence of QCN. Changes brought by CaPFC on top of PFC are lightweight. By conducting simulations in NS-3, we demonstrate that CaPFC handles persistent and flash congestion much better than PFC. For the short messaging traffic and the query traffic, which are sensitive to tail latencies, CaPFC consistently outperforms PFC in terms of tail flow completion time.

A novel high-effective sunlight-induced AgBr/ZnO hybrid nanophotocatalyst has been synthesized and it was characterized by different techniques such as X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and ultraviolet-visible spectrophotometry (UV-vis). The AgBr/ZnO hybrid nanophotocatalyst has excellent photocatalytic activity for photodegradation of methyl orange (MO) under sunlight irradiation. The MO degradation efficiency for AgBr/ZnO is about 98% after 1 hour under sunlight irradiation. These results suggested that AgBr/ZnO is a promising candidate for the development of highly efficient sunlight photocatalysts. In addition, the photocatalytic mechanism of AgBr/ZnO under sunlight irradiation is illustrated and discussed.

Background Acinetobacter baumannii, a significant nosocomial pathogen, has evolved resistance to almost all conventional antimicrobial drugs. Bacteriophage therapy is a potential alternative treatment for multidrug-resistant bacterial infections. In this study, one lytic bacteriophage, ZZ1, which infects A. baumannii and has a broad host range, was selected for characterization. Results Phage ZZ1 and 3 of its natural hosts, A. baumanni clinical isolates AB09V, AB0902, and AB0901, are described in this study. The 3 strains have different sensitivities to ZZ1, but they have the same sensitivity to antibiotics. They are resistant to almost all of the antibiotics tested, except for polymyxin. Several aspects of the life cycle of ZZ1 were investigated using the sensitive strain AB09V under optimal growth conditions. ZZ1 is highly infectious with a short latent period (9 min) and a large burst size (200 PFU/cell). It exhibited the most powerful antibacterial activity at temperatures ranging from 35°C to 39°C. Moreover, when ZZ1 alone was incubated at different pHs and different temperatures, the phage was stable over a wide pH range (4 to 9) and at extreme temperatures (between 50°C and 60°C). ZZ1 possesses a 100-nm icosahedral head containing double-stranded DNA with a total length of 166,682 bp and a 120-nm long contractile tail. Morphologically, it could be classified as a member of the Myoviridae family and the Caudovirales order. Bioinformatic analysis of the phage whole genome sequence further suggested that ZZ1 was more likely to be a new member of the Myoviridae phages. Most of the predicted ORFs of the phage were similar to the predicted ORFs from other Acinetobacter phages. Conclusion The phage ZZ1 has a relatively broad lytic spectrum, high pH stability, strong heat resistance, and efficient antibacterial potential at body temperature. These characteristics greatly increase the utility of this phage as an antibacterial agent; thus, it should be further investigated.

A generic and lightweight service for indoor and outdoor detection is demonstrated that mainly uses three lightweight sensing resources, including light sensors, cell tower signals and magnetism sensors, to make ambient environment detection in a fast, accurate and efficient manner. In particular, we do not need to fingerprint the environment to acquire a priori knowledge. Thus the proposed system greatly benefits many location-based and context-ware applications.

In this demo, we propose a novel clock calibration approach called FLIGHT, which leverages the fact that the fluorescent light intensity changes with a stable period that equals half of the alternating current's. By tuning to the light emitted from indoor fluorescent lamps, FLIGHT can intelligently extract the light period information and achieve network wide time calibration by referring to such a common time reference. We address a series of practical challenges and implement FLIGHT in TelosB motes. In this demonstration, we will show that by taking advantage of the stability of the AC frequency, the detected light intensity, even from different lamps, exhibits a consistent and stable period. FLIGHT can achieve tightly synchronized time with low energy consumption. In addition, since FLIGHT is independent to the network message exchange, time synchronization can be retained even when the network is temporarily disconnected. Such characteristics particularly suit various mobility-enabled scenarios.

Although the SiC/SiO2 nanochain heterojunction has been synthesized, the chained homogeneous nanostructure of SiC has not been reported before. Herein, the novel β-SiC nanochains are synthesized assisted by the AAO template. The characterized results demonstrate that the nanostructures are constructed by spheres of 25–30 nm and conjoint wires of 15–20 nm in diameters. Raman and photoluminescence measurements are used to explore the unique optical properties. A speed-alternating vapor–solid (SA-VS) growth mechanism is proposed to interpret the formation of this typical nanochains. The achieved nanochains enrich the species of one-dimensional (1D) nanostructures and may hold great potential applications in nanotechnology.

Fe-doped Cu3N films were prepared by cylindrical magnetron sputtering equipment at room temperature. The doping of Fe with the proper concentration results in a change in the preferred growth orientation from the Cu-rich plane (1 1 1) to the N-rich plane (1 0 0), which relates to the evolution of the surface grain shape from pyramid to sphere. Excessive doping of Fe is not favourable for the crystallization of Cu3N films. The cross-sections of the doped films with preferred growth orientations of [1 0 0] exhibit regular columnar grains. The variation between the lattice constant and the XPS results reveals that Fe probably replaces the position of Cu atoms in the lattice or is segregated in the grain boundaries. Weaker bonding of Cu–N results in a reduction of thermal stability for Fe-doped Cu3N films. And the incorporation of Fe can effectively modify the energy gap. According to the variations in the mean grain size, the peak of N1s and the energy gap, it is inferred that a doping limitation exists around 2.0 at%.

Background Phage ZZ1, which efficiently infects pathogenic Acinetobacter baumannii strains, is the fifth completely sequenced T4-like Acinetobacter phage to date. To gain a better understanding of the genetic characteristics of ZZ1, bioinformatics and comparative genomic analyses of the T4 phages were performed. Results The 166,687-bp double-stranded DNA genome of ZZ1 has the lowest GC content (34.4%) of the sequenced T4-like Acinetobacter phages. A total of 256 protein-coding genes and 8 tRNA genes were predicted. Forty-three percent of the predicted ZZ1 proteins share up to 73% amino acid identity with T4 proteins, and the homologous genes generally retained the same order and transcriptional direction. Beyond the conserved structural and DNA replication modules, T4 and ZZ1 have diverged substantially by the acquisition and deletion of large blocks of unrelated genes, especially in the first halves of their genomes. In addition, ZZ1 and the four other T4-like Acinetobacter phage genomes (Acj9, Acj61, 133, and Ac42) share a well-organised and highly conserved core genome, particularly in the regions encoding DNA replication and virion structural proteins. Of the ZZ1 proteins, 70, 64, 61, and 56% share up to 86, 85, 81, and 83% amino acid identity with Acj9, Acj61, 133, and Ac42 proteins, respectively. ZZ1 has a different number and types of tRNAs than the other 4 Acinetobacter phages, although some of the ZZ1-encoded tRNAs share high sequence similarity with the tRNAs from these phages. Over half of ZZ1-encoded tRNAs (5 out of 8) are related to optimal codon usage for ZZ1 proteins. However, this correlation was not present in any of the other 4 Acinetobacter phages. Conclusions The comparative genomic analysis of these phages provided some new insights into the evolution and diversity of Acinetobacter phages, which might elucidate the evolutionary origin and host-specific adaptation of these phages. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-793) contains supplementary material, which is available to authorized users.