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Higher multiplexing in droplet digital PCR (ddPCR) can simplify the detection process of ddPCR-based non-invasive prenatal testing (NIPT) and improve its reliability, making it a practical approach in clinical practice. However, a high level of multiplex ddPCR-based NIPT has rarely been reported. In this study, we developed a multiplex ddPCR assay using universal locked nucleic acid (LNA) probes to reliably identify fetal aneuploidies. We first performed statistical analysis based on the Poisson distribution to evaluate the required number of target DNA molecules and the total number of droplets for a ddPCR assay. Next, we designed two sets of primers and probes to quantify cfDNA from chromosomes 21 and 18 and then determined the disease status of a sample. Finally, we evaluated our multiplex ddPCR assay with 60 clinical plasma samples. All of the 60 clinical samples were correctly identified. The accessibility and cost-effectiveness of our multiplex ddPCR-based NIPT make it a competitive prenatal testing method in clinical use.

Purpose As a common transmission line, the microstrip line plays an important role in high-speed circuits. The purpose of this paper was to investigate the effects of the circuit design of microstrip lines on the signal integrity (SI). In addition, the influence of the type and thickness of the solder resist ink on SI was analyzed to provide guidance for the related producing process design of printed circuit boards (PCBs). Design/methodology/approach Microstrip line properties consisting of shape, line-width/line-space ratio, reference layer design and as-covered solder resist ink were designed to measure the insertion loss (S21) in high-speed PCB. Findings The study showed that the insertion loss (S21) of straight, meander, snake-shaped and wavy microstrip lines was approximately consistent. A microstrip line with width/space ratio less than 0.96 is necessary, as the differential line closing produces a mutual interference. Reference layer including the discontinuous area should be repaired by adjusting the microstrip line parameters. With regard to the solder resist ink, the insertion loss of novel solder resist ink decreased by 0.163 dB/in at 12.9 GHz and 0.164 dB/in at 14 GHz, compared with traditional solder resist ink. Accordingly, the insertion loss effectively improved at a lower thickness of solder resist. Originality/value This paper demonstrated that the common designing factors of line shape, line/space ratio, reference layer and solder resist influence microstrip line SI in the significant reference of designer-making PCB layout.

Droplet digital PCR (ddPCR) is a single-molecule amplification technology with broad applications in precision medicine and clinical diagnosis. Dual-fluorescence and four-cluster ddPCR (two/four-ddPCR) assay is an effective way to quantify copy numbers. Currently, two/four-ddPCR data are usually classified with manual thresholds. For clinical applications, automatic and accurate methods are required to avoid subjectivity in diagnosis. Although there are some automatic classification algorithms, their accuracy and robustness still need to be improved to meet the needs of clinical diagnosis. Therefore, a new method is in high demand to automatically classify two/four-ddPCR data in an accurate and robust way. Here, a novel density-watershed algorithm (DWA) method was developed for the accurate, automatic and unsupervised classification of two/four-ddPCR data. First, data gridding was applied to a scatter plot of the fluorescence signal intensity to calculate data densities. Based on the data densities, the watershed algorithm was used to divide the gridded scatter plot into isolated regions automatically. Next, an optimal cluster pattern was determined based on these isolated regions, and excess regions were merged. Finally, the two/four-ddPCR data were classified based on the merged regions, and DNA template copy numbers were calculated accordingly. Using the DWA method for the quantification of both wild types and mutants of epidermal growth factor receptor (EGFR) L858R and T790M, the classification results were highly consistent with expectations, and significantly better than commonly-used automatic algorithms for now. The computed template copy numbers scaled proportionally to the relative concentration of input templates (r2 > 0.998) in four orders of magnitude with a good reproducibility, and achieved a limit of detection over 40 times lower than the commonly-used automatic algorithms. Furthermore, the DWA method was validated on 254 clinical DNA samples derived from frozen tissues, formalin-fixed paraffin-embedded tissues and peripheral blood. In most cases, the DWA method derived accurate and valid classification results. This highly effective DWA method may be widely used for automatically classifying two/four-ddPCR data, and it will greatly promote the application of ddPCR in clinical diagnosis.

Highly-sensitive and contamination-free droplet digital PCR (ddPCR) is an enabling technology and widely needed for accurate quantification of nucleic acid in clinical applications. In this paper, a novel droplet reader was developed by combining a "quasi" confocal laser-induced fluorescence (LIF) cytometry with a delicate microfluidic chip design. The droplets with a size of 90 μm was illuminated at an out-of-focus position by two aligned laser beams to generate maximum fluorescent signal. Additionally, the lateral offset position of the microfluidic chip should be precisely tuned so that the bandwidth of the FAM and VIC channels were configured at the matching sizes. Then, PMT gain voltages and pneumatic pressures were optimized for better droplet detection efficiencies. An aerosol adsorption experiment was performed to demonstrate that there was no aerosol contamination, and detected copy numbers of both mutants and wild types scaled linearly with the expected input copy numbers (r2>0.998) with a LoB of 0.0 copies and LoD of 3.0 copies. The results demonstrated that this droplet reader with the delicate chip is a convenient, highly-sensitive and contamination-free to detect fluorescence signals inside droplets after ddPCR, which is highly promising for broad applications of ddPCR in clinical diagnosis.

The steering performances of the frog skating robot are studied by the equivalent swing arm method. Firstly, the influent factors of the steering radius of the frog skating robot are obtained directly by analyzing the intersection points of the axes among the front and passive wheels, and the research problem is put forward. Further, because of the motion characteristics of the frog skating robot arms swing inward, outward at the same time, or only one arm swings, from a kinematic point of view, the two arms can be replaced by an equivalent arm, which can avoid the uncertainties of the tilt axis deflection angles of the passive wheels that cause obstacles to the analyses of the steering radius of the front wheel, then the formula of the front wheel steering radius is given, and the three kinds of the turning modes and their corresponding minimum steering radius are furtherly researched. Finally, the experiments are presented to validate the method by validating the formula of the front wheel steering radius.

Purpose High-grade mucoepidermoid carcinoma (MEC) is an infrequent malignant neoplasm originates most commonly in the salivary glands with poor prognosis. Thus far, there is little knowledge on MUC-1 expression in high-grade MEC or how it may relate to patient survival. The aim of this study was to determine the extent of MUC-1 expression in high-grade MEC and correlate expression with clinic outcome. Methods Surgical specimens from 62 cases of primary high-grade MEC and 10 cases of normal salivary gland tissue were examined by immunohistochemistry. The relationship between MUC-1 expression and the clinicopathological data and patient survival was analyzed. Results The disease-free survival rates were 54.6% (3 years) and 37.7% (5 years) for high-grade MEC patients. Patient who with primary location at submandibular gland have the worst prognosis (P = 0.042) in comparing with other sites. High expression of MUC-1 in high-grade MEC was significantly correlated with lymphatic/regional metastasis (P = 0.003) and clinic stage (P = 0.02), and high expression of MUC-1 (>75%) was confirmed to be significant independent prognostic factors in high-grade MEC patients [HR 2.929 (95% CI 1.246–6.881); P

Purpose The purpose of the present study was to present a new method that combines the use of the fibular flap and a custom-made vertical distractor/dental implant device into 1 surgical procedure for simultaneous functional mandibular reconstruction. Patients and Methods The present retrospective case series included 10 patients who were treated using the fibular flap and dental implant distractor (DID) in a single-stage procedure. These 10 patients were treated within a 3-year period (from 2005 to 2007). Results Of the 10 patients included in the study, 5 were males and 5 were females. The mean age of the sample was 33.8 years (range 17 to 48). The cumulative survival rate of the fibular flaps was 100%. The mean vertical bone height attained with the DID device was 11.4 mm. The mean period from the first operation to the start of dental implant loading was 6.3 months. The cumulative survival rate of the dental implants was 93.75%. Conclusions The use of the DID in the fibular flap for mandibular reconstruction is advantageous because it combines vertical distraction osteogenesis of the fibular flap and dental implantation into a single procedure. Implants placed in the reconstructed areas were found to integrate normally, with survival rates comparable to those with 2-stage operations. As such, this novel DID technique can be used for single-stage reconstruction and rehabilitation of segmental mandibular defects in selected patients.

According to the motion principle of the frog scooter, a kind of novel mobile robot with passive wheels called Frog Skating Robot is designed. The robot consists of three passive wheels, and the steering of the two rear passive wheels are controlled indirectly. There are only 3 DOF of the robot need to be controlled. The driving forces of the robot come from the frictions between the wheels and the ground. In this paper, the motion differential equation of the robot is established using generalized Lagrange-Routh equation when nonholonomic constraints exist. The derived equations are tested by the gait of the linear motion with double-arms symmetrical swing. The experimental results are presented to validate all above analyses.

Integrated inductor with magnetic core is one of the three significant passive components for PCB (Printed Circuit Board) assembly. In this paper, a novel structure of integrated inductor with Ni-P (low P content) magnetic core deposited on the as-patterned conductive copper lines was fabricated by directly electroless-plating method. Two types of PCB integrated inductor with patterns of rectangle and hexagon winding were designed, respectively. The inductance changes were investigated under the changes of Ni-P plating times and tested frequency. Obvious increasing was observed after the deposition of Ni-P magnetic core. Furthermore, effects of the P content of Ni-P thin-film were also investigated in this paper.

Objective Primary desmoid-type fibromatoses arising from the oral and maxillofacial region are uncommon and hold the character of local invasion and regional recurrence. The purpose of this study was to analyze the clinicoepidemiologic characteristics of this rare disease in an eastern Chinese population. Study design Epidemiological and clinicopathological data on 20 patients were reviewed from the hospital records and analyzed accordingly. Results Twelve males and 8 females with a ratio of 3:2 were involved. The mandible was the most common site of presentation. Suspected malignant change was found in 6 cases and an extremely high recurrence rate was also found in up to 53%. Abnormally high blood levels of alkaline phosphatase were found in 65% of patients, which had a close relation with tumor malignant change. Conclusion Chinese people are more susceptible to desmoid-type fibromatoses and are at an extremely high risk of regional malignant change. Elevated serum alkaline phosphatase levels may be taken as an indicator for malignant transformation.

Based on the analytical expression of the electromagnetic field solution of a helical symmetric dielectric material, the relationship between spectral reflectivity and birefringence of a chiral liquid crystal and the blue shift of the Bragg reflection in the condition of oblique incidence are presented in this paper. The theoretical results indicated that: 1) If birefringence (Δn) of the liquid crystal is greater than 0.2 and the thickness of the liquid crystal layer reaches 3 μm, the liquid crystal layer will reflect more than 90% of the incident light; 2) To reflect the whole visible spectrum by Bragg reflection, Δn of the liquid crystals in plane alignment state should exceed 0.6; 3) When the incident beam inclines to 60° from the normal direction, the blue shift of the reflective spectrum will reach to 100 nm. On the other hand, since the Δn of the commercial chiral liquid crystals is not larger than 0.2, to get the entire visible reflective spectrum, it needs to introduce a polymer network into the liquid crystals and make a sagging structure on the surface of substrates. The contribution of the network is to establish random anchorage that makes the pitch varied, hence broadening the Bragg reflection spectra. The random distribution of the sagging structure on the surface substrate is used to induce random screw axes of the chiral liquid crystal, which not only causes a blue shift of Bragg reflection but also further stretches the reflection spectra. Experiments demonstrated that the Bragg reflection spectrum could be broadened from 80 nm to more than 120 nm, and the contrast reaches 4:1 by introducing both polymer network and sagging structure on the substrate surface cell.

The most widely accepted treatment for neoplasms of the submandibular gland usually involves excision of the entire gland. Our aim was to establish a gland-preserving operation for benign tumours of the submandibular gland and evaluate its efficacy. We treated 40 patients from January 2007 to December 2008 with benign submandibular gland tumours who were listed to have an operation that either preserved the gland or sacrificed it. Duration of operation, extent of injury to the nerve, postoperative function of the gland, aesthetic appearance, and recurrence were assessed. We found no significant difference in baseline characteristics among the 20 patients in each group (19 men; 21 women, mean (SD) age of 34 (33.8 ± 5.72) years. The extent of injury to the lingual nerve and submandibular branch, together with deformities of the facial contour, were significantly less in the group in which the gland was preserved. Postoperative salivary production and overall patients' satisfaction were also better in that group. There was no recurrence in either group during the follow up period of 38 months-5 years. The gland-preserving procedure has advantages over the typical approach in which the gland is sacrificed. There is less risk of injury to the nerve, less deformity of the facial contour, better preservation of function, and patients are more satisfied. The gland-preserving technique should therefore be the first choice for management of benign submandibular tumours.

Adenoid cystic carcinoma (ACC) is an infrequent malignant neoplasm that originates most commonly in the major and minor salivary glands of the head and neck region. This study provides new information on head and neck ACC with cervical lymph node metastasis. Of 616 patients who underwent primary tumour resection from 1995 to 2008 in the authors' hospital, 62 cases with cervical lymph node metastasis were analyzed. The general incidence of cervical lymph node metastasis in ACC was approximately 10%. The base of tongue, mobile tongue and mouth floor were the most frequent sites of lymph nodes metastasis, with incidences of 19.2%, 17.6% and 15.3%, respectively. Most cases occurred via a classic 'tunnel-style' metastasis and the level Ib and II regions were the most frequently involved. Primary site and lymphovascular invasion were significantly associated with lymph node metastasis. High patient mortality was significantly correlated with lymph node positive cases. The tongue-mouth floor complex has a high propensity for cervical lymph node metastasis, which occurs through a classic 'tunnel-style' metastasis. Peritumoral lymphovascular invasion could be taken as strong predictor for lymph node metastasis, which ultimately leads to poor prognosis of ACC patient. Selective neck dissection should be considered in such cases.

Power transform is a nonlinear pretreatment method, which can improve the recognition rate of high resolution range profiles obviously. This paper mainly analyses how we should decide the power transform coefficient in order to get good recognition results. We process the range profiles in different noise condition using different power transform coefficients, and then we classify them with radial basis function classifiers. According to the real data processing results, we know that we should decide power transform coefficients in accordance with the signal-to-noise ratio. (4 pages)

Semantic based Web services integration aims to add valuable semantic information in Web services description and to implement the semantic based Web services discovery and integration. This paper puts forward a semantic based Web service integration framework in P2P-SEWSIP. SEWSIP can collect Web services in distributed Web environment, lift the WSDL files into OWL-S by the use of XML schema in WSDL and domain ontology, and then deploy them in P2P. It also can provide service discovery, evaluation and composition based on semantic information in OWL-S.

SOC (service-oriented computing) is the new emerging paradigm for distributed computing and e-business processing, whose vision is to integrate autonomic Web services as distributed components into a complicated application. Current composed service processes are mostly generated in the syntactic level and in a manual way. The limitation of such a rigid approach is that it does not allow businesses to dynamically change partners and services like in "framework for semantic Web process composition" by K. Sivashanmugam. Some semi-automatic Web service composition frameworks are present based on both semantic matchmaking and process recommendation in terms of semantic description of user requirements and concrete Web services. However, two problems need to be crossed over in these frameworks. How to design the activities in the process with the exact clarity that can be bound to concrete Web service, and how to deal with the problem that the output message type of the preceding service is subtly heterogeneous with the input one of the subsequent service? This paper addresses these two problems and proposes a solution in SEWSIP, a semantic based Web service integration platform. A hierarchical activity mechanism used to control activity clarity and a message transforming mechanism used to eliminate message type heterogeneity, are mainly discussed.

Stateful network services are a growing population of applications in the Internet, whose architecture relies more and more on COTS components. A good parallel programming model is the key to the success of network services. We argue that stage-based parallel programming model is the most suitable candidate, which takes the whole service logic as a set of stages interconnected by event queues, and in each stage, one or multiple threads reside to service messages. And we also reveal several key design principles for this model. 1) The number of stages should not be over 10 for a single CPU system. 2) For stages with blocking calls, a good estimation of the number of threads for that stage can be gotten by (call arrival rate blocking time) and moreover excessive threads give minor performance degradation. 3) To deliver message quickly, it is much better to locate this part of service in a separate nonblocking stage.