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Yam (Dioscorea opposita Thunb.) is cultivated mainly as a functional food and for nutritional and medicinal purposes in China (1). It is propagated through tubers and this facilitates the spread and accumulation of viruses in the crop, eventually leading to yield losses (2). At present, different virus species belonging to the genera Aureusvirus, Badnavirus, Carlavirus, Comovirus, Cucumovirus, Fabavirus, Macluravirus, Potexvirus and Potyvirus have been reported in yams (3) and fifteen viruses in these genera have been detected in China. In July 2020, a survey of viral diseases on yam was conducted in plantations of Wenxian and Mengzhou counties in Henan Province, China. Fifty-four leaf samples of Dioscorea opposite showing mosaic and leaf discoloration (Supplementary Fig1) were collected from eight fields (five to ten plants per field). These leaf samples were ground in liquid nitrogen and total RNA was extracted from a portion of the mixed powder using RNAprep Pure Plant Plus Kit (TIANGEN Biotech, Beijing, China). A cDNA library was constructed using NEBNext Ultra RNA Library Prep Kit for Illumina (NEB, USA) after ribosomal RNA depletion using Ribo-off rRNA Depletion Kit (Vazyme Biotech, Nanjing, China), and sequenced on the Illumina NovaSeq 6000 system at the Berry Genomics Corporation (Beijing, China). A total of 87,075 contigs (200 bp) were generated from de novo assembly (CLC Genomic Workbench 10.0) from a total of 34,656,172 paired-end reads. After BLASTn analysis, three contigs with the length of 1009, 1340 and 1859 nucleotides shared 96.33%, 96.72% and 96.29% nt identity respectively with youcai mosaic virus SX isolate, a tobamovirus (YoMV GenBank accession no. JX422022). In addition to YoMV, broad bean wild virus 2 and yam latent virus were also identified, which had previously been reported in yams in China. To confirm the NGS result, total RNAs were extracted from fifty-four above-mentioned samples and RT-PCR was carried out to amplify a 528 bp fragment of the coat protein (CP) of YoMV by using a pair of specific primers CP gene. PCR products with expected size were obtained from 26 out of 54 samples, and seventeen amplicons of YoMV-CP were sequenced (accession nos. ON052726 to ON052742). The nt sequence identities of CP gene among these seventeen isolates were 99.6%-100%. Furthermore, the near-full-length genomic sequence of YoMV-Do41 isolate was obtained from sample 41 by RT-PCR amplification of four overlapping fragments using the following primer pairs: YoMV-15F/YoMV-1910R, YoMV-1770F/YoMV-3750R, YoMV-3645F/YoMV-5404R and YoMV-4921F/YoMV-6280R (Supplementary Table1). The YoMV-Do41 isolate was 6, 274 nt in length (accession no. ON149803) and shared 89.65% and 97.31% nt identities to As1-2 isolate (GenBank accession no. MW307290) and to SX isolate (accession no. JX422022), respectively.To the best of our knowledge, this is the first report of YoMV infecting yam in China. YoMV has a wide host range including genera Impatiens, Rehmannia, Brassica, Chelidonium, Trifolium, Crossandro, Alstroemeria, Stellaria. This study will serve as an important reference for the host range of YoMV. According to the detection rate infections with YoMV in yam are common in these producing regions. Further studies will be required to determine the infection rate in other producing regions and the potential threat posed by YoMV on yam production should be considered.

Rehmannia glutinosa (family Scrophulariaceae) is an important traditional medicinal plant, whose root is used to treat anemia, hemoptysis, and gynecological diseases in China (Matsumoto et al. 1989). This plant is native to China and cultivated in China, Korea, Japan, and northern Vietnam (Kwak et al. 2020). Viral diseases caused remarkable loss in the yield and quality of R. glutinosa (Ling et al. 2009). To date, ten viruses have been identified globally to infect R. glutinosa and seven of these viruses reported in China (Liu et al. 2018; Zhang et al. 2021). Most plants of R. glutinosa are infected with one or more of these viruses (Kwak et al. 2018; Zhang et al. 2004). In July 2020, a survey of the viral disease infecting R. glutinosa was conducted in commercial plantations of Wenxian, Wuzhi, Mengzhou, and Yuzhou counties in Henan Province, China. The disease symptoms included mosaic, chlorosis, leaf distortion, and the percentage of symptomatic plants was over 70% in the surveyed fields (n=9). Sixty leaf samples of symptomatic R. glutinosa plants were collected from nine cultivation fields in Wenxian, Wuzhi, Mengzhou, and Yuzhou counties (five to seven plants for each field). Total RNA was extracted from one pooled sample containing a portion of all above-mentioned leaf samples using RNAprep Pure Plant Plus Kit (TIANGEN Biotech, Beijing, China) and analyzed by high-throughput sequencing (HTS) to identify viral pathogens. A transcriptome library was generated using NEBNext Ultra RNA Library Prep Kit for Illumina (NEB, USA), and sequenced on an Illumina NovaSeq6000 sequencing system at Berry Genomics Corporation (Beijing, China). A total of 27,664,949 high-quality clean reads were obtained after trimming and used for contig assembly. The assembled contigs (n=109,180) were searched using Basic Local Alignment Search Tool (BLAST) at GenBank. BLASTn analysis showed that the R. glutinosa plants were infected with known viruses, including broad bean wilt virus, rehmannia mosaic virus, youcai mosaic virus, and cucurbit chlorotic yellows virus. In addition, one contig (6,418 nt in length) had a nucleotide sequence identity of 99.64% with the TN29 isolate of tobacco mild green mosaic virus (TMGMV, GenBank accession no. MF139550). To confirm the presence of this virus, sixty above-mentioned samples were screened by reverse transcription-polymerase chain reaction (RT-PCR) using the specific primer pairs (Supplementary Table1) TMGMG-CPF/TMGMG-CPR targeting a 545-nt fragment within the CP gene. Amplicons with expected sizes were detected from 47 of 60 samples but not from the negative control (virus-free healthy plant through the tip meristem culture). Seventeen amplicons (11#, 13#, 14#, 21#, 22#, 23#, 25#, 26#, 27#, 31#, 32#, 33#, 37#, 52#, 57#, 59#, and 60#) of TMGMV-CP were selected, and purified. The PCR products were cloned into the pMD19-T vector (TAKARA Biotech, Dalian, China) and sequenced. The sequences were deposited into the GenBank (accession nos. MZ395944 to MZ395960). The near-full-length genomic sequence of TMGMV-Rg14 isolate was obtained from one positive sample (sample no. 14) by RT-PCR amplification of two overlapping fragments using the following primer pairs: TMGMV-40F/TMGMV-3570R and TMGMV-3220F/TMGMV-6400R. The near-full-length genomic sequence of the TMGMV-Rg14 isolate was 6 304 nucleotides (nt) in length and deposited into GenBank (accession no. MZ395975). BLASTn analysis demonstrated that the TMGMV-Rg14 isolate shared a sequence identity ranging from 96.89% (AB078435) to 99.60% (MF139550) with the other TMGMV isolates. Furthermore, the virus-free healthy R. glutinosa plants were inoculated with sap from the positive sample (14#) to confirm the infection of TMGMV. Mosaic symptoms were induced on the systemically infected leaves of the inoculated plants 14 days post inoculation. The systemically infected leaves of inoculated plants were assayed by RT-PCR using the primer pairs TMGMV-CPF/CPR. Amplicons of expected size were detected from the inoculated plants but not from non-inoculated plants. To our knowledge, this is the first report of TMGMV infection on R. glutinosa. Further studies are necessary to select a suitable indicator plant for this TMGMV, its host range, and the symptoms it induces in single infection. Since R. glutinosa is cultivated by vegetative propagation, production of virus-free healthy plants is necessary. This study will help to generate virus-free healthy plants and prevent viral disease on R. glutinosa. Further study is needed to determine its pathological implications and economic impact on R. glutinosa in China.

The effects of various concentrations of bensulfuron-methyl residues (BSM, 0–500 μg kg–1) on the growth and photosynthesis of soybean and peanut were studied. Shoot length, root length, root-to-shoot ratio, and biomass of soybean and peanut seedlings declined with the increase of BSM residue concentrations. As the concentration of BSM increased, SPAD value, net photosynthetic rate, stomatal limitation, stomatal conductance, and transpiration rate also declined with varying extent, but dark respiration rate and intercellular CO2 concentration increased gradually. PSII maximum quantum yield, actual quantum yield, and electron transport rate were significantly reduced by the BSM residues in soil, and the reduction was mostly attributed to the decrease in photochemical quenching coefficient. The results showed that photosynthesis in both crops was limited by nonstomatal factors. The residues of BSM caused reversible damage in PSII reaction centers and decrease the proportion of available excitation energy used for photochemistry.

The influence of various concentrations of imazapic residues (0–800 μg kg–1) on the growth, chlorophyll content, and photosynthetic characteristics of maize seedlings was studied in a greenhouse pot experiment. Plant height, root length, shoot dry mass, root dry mass, and total dry mass of maize declined with the increase of imazapic residue concentrations. The root/shoot ratio initially decreased and then increased in presence of imazapic, which indicated that the effects of imazapic residues on plant height and root length might differ in maize seedlings. Lowered chlorophyll content and net photosynthetic rate were observed in leaves of maize seedlings in all treatments and indicated a dose-response relationship to imazapic concentrations. Intercellular carbon dioxide concentration, transpiration rate, and stomatal conductance also declined to varying extents, but the chlorophyll a/b ratio increased gradually together with the increase of imazapic residue concentrations. Generally, the maize seedlings were negatively affected by the imazapic residues in soil. Response of root length and biomass to imazapic residues could be the important index for maize variety selection.

Safety is always an important issue in the construction industry. An increasing number of construction projects are carried out in the recent decades to meet the ever increasing demand from population increase. To grasp the growth rate of construction accidents, safety measures and planning are necessary. Indeed, it is essential to forecast the accident rates based on relative factors to support an efficient planning and propose suitable safety measures for lowering the accident numbers. This paper aims to examine the potential accident-related factors and investigate their relationship with accident rates by developing a forecasting model. Three types of accident-related factors including working conditions, environmental factors and management actions are selected for investigating their relationship with the construction accident rates. The result indicates the forecasting model with efficiency up to 56.7%. It is also showed the accident rate highly depends on the number of vacancies, the numbe...

Currently, a reflective polarizer is always used between the backlight units and LCD panels to circumvent this problem; however, the improvement afforded by its use is limited. Because a nano-wire grid polarizer (NWGP) has been demonstrated to be a reflective polarizer. In this study, we fabricated an NWGP using LIGA technology. E-beam lithography and gold electroforming were employed to generate an X-ray mask; deep X-ray lithography was then applied to pattern the closely-packed, sub-micron-size, and high-aspect-ratio NWGP microstructure. The minimum feature size was approximately 0.7um and the height was 6 um (aspect ratio=9). Preliminary measurement results demonstrated that the optical reflection intensity from the substrate was clearly lower when the NWGP structure was applied; additionally, the reflective intensity decreased with increasing NWGP height(due to the month's eye effect). In the near future, the reflective spectrum in the visible light rage will be measured to evaluate the feasibility of using an NWGP to improve the performance of LSCs.

The aim of this study was to compare the pharmacokinetic characteristics of phloroglucinol between an orally disintegrating tablet and an orally lyophilized tablet of phloroglucinol in healthy volunteers under fasting condition.A rapid and simple method based on high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method has been developed and validated for the determination of phloroglucinol in human plasma. The plasma sample was prepared by liquid-liquid extraction, and paracetamol was chosen as the internal standard. Phloroglucinol and IS were separated on a C18 column with a mobile phase consisted of methanol/water (80:20 v/v) with 0.02% formic acid. HPLC-MS/MS analyses were performed on a triple- quadruple tandem mass spectrometer by monitoring protonated parent→daughter ion pairs at m/z 125.0→56.9 for phloroglucinol, and m/z 150.2→107.0 for paracetamol (IS). The method was the high sensitivity with a lower limit of quantification (LLOQ) of 1.976 ng/mL.Drug and IS were detected by HPLC/MS/MS with negative electrospray ionization (ESI). Accuracy and precision for the assay were determined by calculating the intra- and inter-batch variation of quality control (QC) samples at three concentration levels. The relative standard deviation (RSD) was less than 15.0%. The detection and quantitation of drug and IS within 4.5 min make this method suitable for high-throughput analyses. In this study, the Cmax of phloroglucinol were calculated to 515.6 ± 134.4 ng/mL and 536.0 ± 144.8 ng/mL for the test drug and the reference drug, respectively. The AUC0-t values were 459.5 ± 81.03 ng·mL-1·h and 491.8 ± 95.17 ng·mL-1·h for the test drug and the reference drug; 24 subjects completed the study, respectively. The geometric mean ratio (GMR) and the 90% confidence intervals (CIs) of Cmax and AUC0-t of phloroglucinol were 97.1 (90.2-103.9) and 93.8 (88.7-99.2), respectively.The method was employed for the first time during pharmacokinetic studies of phloroglucinol in human plasma following a single dose of phloroglucinol 160 mg tablets. There was no significant difference in pharmacokinetic profiles between the two treatments.

With the development of forest tourism, Color-leaf forest has gradually become one of the most popular tourism destination. Based on related researches about forest landscape evaluation, this paper takes Jinyang village as the research object, which is known as the “Western Ginkgo No. 1 Village”, to conduct scenic beauty evaluation (SBE) on different scales of the same landscape. The result shows that the landscape outside the forest is affected by terrain changes, overall landscape combination, landscape contrast, human landscape, and human activities; the landscape inside the forest is affected by diameter, color of the leaves, composition and density of the forest, and leaf coverage. The results will provide some references for the practice of forest landscape planning in China.

This study uses the travel cost method (TCM) and the tourism market demand curve to evaluate the recreational value of the Color-leaf forest resources in Bipeng Valley Scenic Spot at the first time, which contributes to the utilization and management of the Color-leaf forest resources, and also discusses the importance and value of forestry resources. The results show that the research value of the research and development of the Color-leaf forest resources was 1567.48 million Yuan, which is 13 times the actual income of the Bipeng Valley Scenic Spot. It means scenic spot should avoid idle resources, improve its product mix and protect the Color-leaf forest resources to realize the sustainable use of forest resources of arid and semi-arid area of sichuan province.

Various microstructural zones were observed in the solidified solder of flip-chip solder joints with three metal bond-pad configurations (Cu/Sn/Cu, Ni/Sn/Cu, and Cu/Sn/Ni). The developed microstructures of the solidified flip-chip solder joints were strongly related to the associated metal bond pad. A hypoeutectic microstructure always developed near the Ni bond pad, and a eutectic or hypereutectic microstructure formed near the Cu pad. The effect of the metal bond pads on the solder microstructure alters the Cu solubility in the molten solder. The Cu content (solubility) in the molten Sn(Cu) solder eventually leads to the development of particular microstructures. In addition to the effect of the associated metal bond pads, the developed microstructure of the flip-chip solder joint depends on the configuration of the metal bond pads. A hypereutectic microstructure formed near the bottom Cu pad, and a eutectic microstructure formed near the top Cu pad. Directional cooling in the flip-chip solder joint during the solidification process causes the effects of the metal bond-pad configuration. Directional cooling causes the Cu content to vary in the liquid Sn(Cu) phase, resulting in the formation of distinct microstructural zones in the developed microstructure of the flip-chip solder joint.

Comparative study on the interfacial reactions between lead-free Sn-Ag-Cu solder and Ni(P) bond pads (with columnar or layered microstructure) has been performed. The microstructure of the columnar Ni(P) is vertical, while the microstructure of the layered Ni(P) tends to be parallel to the solder/Ni(P) interface. The consumption rate of the columnar Ni(P, 7 at.%) layer is larger than that of the layered Ni(P, 7 at.%). We believe that the faster Ni(P) consumption rate of the columnar Ni(P, 7 at.%) layer is due to the orientation of the grains. Spalling of the interfacial (Cu,Ni)6Sn5 compound can be seen at the reaction interfaces for the columnar Ni(P, 7 at.%) layer. On the contrary, no spalling can be seen for the case of the reacted layered Ni(P).

Epitaxial Cu3Sn and Cu6Sn5 grown by liquid-phase electroepitaxy (LPEE) have been demonstrated in this work. X-ray diffraction analysis reveals that LPEE-grown Cu3Sn and Cu6Sn5 grew in particular directions (planes) with respect to the electron flow. LPEE-grown Cu3Sn grew in the 〈0 2 0〉 and 〈4 0 0〉 directions, and LPEE-grown Cu6Sn5 grew in the 〈2 0 4〉 and 〈 6 2 3 ¯ 〉 directions. With the aid of a molecular simulation software tool, we conclude that the particular growth directions represent the low-resistance paths for electron flow. This means that, along those particular directions in the LPEE-grown Cu–Sn compounds, the traveling electrons would be scattered least by the lattice. Thus, as the electromigrating Cu atoms form Cu–Sn compound, the newly forming Cu–Sn unit cells would orientate themselves in those particular growth directions to facilitate electron flow. Then, the well-oriented newly formed Cu–Sn compound unit cells can incorporate the growth of the highly orientated LPEE-grown Cu–Sn compounds. In addition, the anisotropy of a number of properties of LPEE-grown Cu3Sn and Cu6Sn5, i.e. coefficient of thermal expansion, Vickers microhardness and electrical properties (resistivity, carrier mobility and carrier concentration), along the particular orientations were measured and reported.

This study investigates the electromigration (EM) effect under a high current density (104 A/cm2) on the different interfacial compound phases at Sn(Cu) solder/electroless nickel immersion gold (ENIG) interfaces. The interfacial Ni3Sn4 phase at the Sn-0.7 wt.%Cu/ENIG joint interface was quickly depleted after a short period (50 h) of current stressing. The inference drawn is that the Ni atoms in the Ni3Sn4 phase at the joint interface are likely forced out under current stressing; however, the ternary (Cu,Ni)6Sn5 compound effectively reduces the EM-driven Ni flux into the Sn bump; thus, a significantly lower Ni(P) consumption was observed at the Sn-1 wt.%Cu/ENIG interface. The EM-induced Ni(P) dissolution rates in the Sn-0.2 wt.%Cu/ENIG and Sn-1 wt.%Cu/ENIG cases were calculated to be 0.028 μm/h and 0.018 μm/h, respectively. In addition, significant EM-assisted Ni3P formation was observed for the current-stressed Sn-0.2 wt.%Cu/ENIG and Sn-0.7 wt.%Cu/ENIG cases; however, for the Sn-1 wt.%Cu/ENIG case, formation of a Ni3P layer was scarcely observed. Moreover, the initial (Cu,Ni)6Sn5 that formed at the interface appeared compact with a layer-type structure, which reduced the EM-driven Ni diffusion.

Cross-interactions between Cu/Sn/Pd and Ni/Sn/Pd sandwich structures were investigated in this work. For the Cu/Sn/Pd case, the growth behavior and morphology of the interfacial (Pd,Cu)Sn4 compound layer was very similar to that of the single Pd/Sn interfacial reaction. This indicates that the growth of the (Pd,Cu)Sn4 layer at the Sn/Pd interface would not be affected by the opposite Cu/Sn interfacial reaction. We can conclude that there is no cross-interaction effect between the two interfacial reactions in the Cu/Sn/Pd sandwich structure. For the Ni/Sn/Pd case, we observed that: (1) after 300 s of reflow time, the (Pd,Ni)Sn4 compound heterogeneously nucleated on the Ni3Sn4 compound layer at the Sn/Ni interface; (2) the growth of the interfacial PdSn4 compound layer was greatly suppressed by the formation of the (Pd,Ni)Sn4 compound at the Sn/Ni interface. We believe that this suppression of PdSn4 growth is caused by heterogeneous nucleation of the (Pd,Ni)Sn4 compound in the Ni3Sn4 compound layer, which decreases the free energy of the entire sandwich reaction system. The difference in the chemical potential of Pd in the PdSn4 phase at the Pd/Sn interface and in the (Pd,Ni)Sn4 phase at the Sn/Ni interface is the driving force for the Pd atomic flux across the molten Sn. The diffusion of Ni into the ternary (Pd,Ni)Sn4 compound layer controls the Pd atomic flux across the molten Sn and the growth of the ternary (Pd,Ni)Sn4 compound at the Sn/Ni interface.

In this paper we presented the study of an AlGaN/GaN heterostructure with the presence of a two-dimensional electron gas (2DEG) by using X-ray reciprocal space mapping (RSM), reflectance (R), photoluminescence (PL), electroreflectance (ER) and photoconductivity (PC) measurements. Some important properties such as alloy composition, strain status and layer thickness of Al x Ga 1− x N layer and carrier concentration of 2DEG are determined. The structure strain was analyzed by asymmetric RSM. We observed that the AlGaN layer grown on GaN layer was fully strained. The band gap energies of GaN and Al x Ga 1− x N are identified by PL and R spectrum, from which the Al composition x is determined to be 0.13. Using a semitransparent gate, an external dc bias was applied to control the carrier concentration of 2DEG underneath the Al x Ga 1− x N layer. We have also performed the ER and PC measurements at various external dc biases. In the ER spectra, not only the energy gap transitions of GaN and Al x Ga 1− x N but also the 2DEG feature and the Franz–Keldysh oscillations (FKOs) were observed. Through the analysis of FKOs, the strength of surface electric field and the 2DEG concentration can be determined. The optical absorption phenomenon in the AlGaN/GaN interface observed by the bias-dependent PC spectroscopy are presented and discussed.

The growth mechanism of an interfacial (Cu,Ni)6Sn5 compound at the Sn(Cu) solder/Ni(P) interface under thermal aging has been studied in this work. The activation energy for the formation of the (Cu,Ni)6Sn5 compound for cases of Sn-3Cu/Ni(P), Sn-1.8Cu/Ni(P), and Sn-0.7Cu/Ni(P) was calculated to be 28.02 kJ/mol, 28.64 kJ/mol, and 29.97 kJ/mol, respectively. The obtained activation energy for the growth of the (Cu,Ni)6Sn5 compound layer was found to be close to the activation energy for Cu diffusion in Sn (33.02 kJ/mol). Therefore, the controlling step for formation of the ternary (Cu,Ni)6Sn5 layer could be Cu diffusion in the Sn(Cu) solder matrix.

The interfacial reactions between electroplated Ni-yCo alloy layers and Sn(Cu) solders at 250°C are studied. For pure Co layers, CoSn3 is the only interfacial compound phase formed at the Sn(Cu)/Co interfaces regardless of the Cu concentration. Also, the addition of Cu to Sn(Cu) solders has no obvious influence on the CoSn3 compound growth at the Sn(Cu)/Co interfaces. For Ni-63Co layers, (Co,Ni,Cu)Sn3 is the only interfacial compound phase formed at the Sn(Cu)/Ni-63Co interfaces. Unlike in the pure Co layer cases, the Cu additives in the Sn(Cu) solders clearly suppress the growth rate of the interfacial (Co,Ni,Cu)Sn3 compound layer. For Ni-20Co layers, the interfacial compound formation at the Sn(Cu)/Ni-20Co interfaces depends on the Cu content in the Sn(Cu) solders and the reflow time. In the case of high Cu content in the Sn(Cu) solders (Sn-0.7Cu and Sn-1.2Cu), an additional needle-like interfacial (Ni x ,Co y ,Cu1−x−y )3Sn4 phase forms above the continuous (Ni x ,Cu y ,Co1−x−y )Sn2 compound layer. The Ni content in the Ni-yCo layer can indeed reduce the interfacial compound formation at the Sn(Cu)/Ni-yCo interfaces. With pure Sn solders, the thickness of the compound layer monotonically decreases with the Ni content in the Ni-yCo layer. As for reactions with the Sn(Cu) solders, as the compound thickness decreases, the Ni content in the Ni-yCo layers increases.

This article proposes a type of transtibial socket composed of an inner layer fabricated by a rapid prototyping (RP) machine and an outer layer coated with unsaturated polyester resin. This work integrates contemporary technologies including a handheld scanner and CAD systems, to design a thin primary socket shape and then manufactures the socket using a fused deposition-modeling machine. To prevent breakage caused by the layer-based forming process and to reinforce flexural strength, the current research coats the preliminary RP socket with a layer of unsaturated polyester resin. After shaping the proximal brim of the resin-reinforced RP socket to match the specific stump, this study assembles and aligns a shank and a prosthetic foot to form a prosthesis set. After completing a trial safety walk wearing the prosthesis, which is satisfactory to the amputee and a registered prosthetist, this research measures interface pressures between the stump and the resin-reinforced RP socket. Experiment results demonstrate that the resin-reinforced RP socket is applicable for transtibial amputees. In addition to strengthening the FDM socket and producing consistent socket fit, this study also demonstrates a feasible procedure that employs current technologies to design and manufacture transtibial sockets without plaster moulds.

We present the photoluminescence (PL) and Hall studies on the two-dimensional electron gas (2DEG) of etched and unetched In 0.5 Al 0.5 As/In 0.5 Ga 0.5 As metamorphic high electron mobility transistor (mHEMT) structures. The PL technique is shown to be capable of extracting the 2DEG sheet carrier concentration in a complete mHEMT structure directly without making contacts or processing, while the Hall measurement gives a substantially higher concentration due to the parallel conduction of the heavily doped cap layer. We also report a new frequency-dependent photo-Hall technique to obtain the absorption coefficient of the In 0.5 Ga 0.5 As quantum-well channel layer.

To review the results of elective laparoscopic anterior resection (LAR) for recurrent and complicated sigmoid diverticulitis, and determine the factors associated with surgical complications.Data on patients who had had elective surgery for recurrent and complicated sigmoid diverticulitis were extracted from a prospective computerized database.Review of the database revealed 62 consecutive patients who had undergone LAR. These patients were initially compared with 20 patients who had undergone elective open anterior resection (OAR). There were no significant differences between the groups in relation to age, sex, indication for surgery, Hinchey stage of perforation, extent of adhesions or comorbidities. The intraoperative time for LAR was significantly shorter (mean+/-SEM 110.87+/-4.8 min vs. OAR 134.35+/-8.4; p=0.032) and blood loss was less (88+/-18 ml vs. OAR 134+/-24 ml; p=0.003). Postoperative passage of flatus occurred earlier after LAR (p0.003). Hospital stay was shorter after LAR (p0.001). Complications occurred in nine patients (15%) after LAR and in six patients (30%) after OAR (p=NS). Among the LAR patients the risk of complications was higher in those with preexisting comorbidities (p=0.037). Time to postoperative passage of flatus correlated positively with age (p=0.004).Elective LAR for recurrent and complicated sigmoid diverticulitis could be performed safely and expediently. Bowel function recovered later in older patients. The risk of medical complications was related to preexisting comorbidities.

This study aims to employ the technology of rapid prototyping for the development of a process that is to assist a prosthetist for easily designing and manufacturing a prosthetic socket for specific transtibial amputee. Currently, the production of prosthetic socket still depends on prosthetists’ skills and expertise. To improve its tedious process, quality uncertainty, and lack of experienced prosthetists, the benefits of using rapid prototyping (RP) technology together with computer-aided systems will be expecting goals. This article demonstrated the feasibility of producing RP sockets using a fused deposition modeling (FDM) machine, and a prototype system that allows a prosthetist to easily design prosthetic sockets has been developed. This proposed computer-aided engineering process, which is plaster-free method, is expected to replace the manual process of conventional approach of fabricating prosthetic sockets. Furthermore, since thin-layer RP socket is easily broken, coating a resin layer on RP socket to enforce its strength is underway.

Electrical discharge machining (EDM) is a machining process transforming electric energy into thermal energy to remove materials. The current impulse is a very important factor for machining characteristics of EDM. A series of experiments were performed to investigate the influence of current impulse on machining characteristics. The features of current impulse have initial current, current rising slope and impulse pattern. The used patterns of current impulse included rectangular current impulse, trapezoidal current impulse and the 1st order current impulse. The machining characteristics are associated with relative wear ratio (RWR) and material removal rate (MRR). Experimental showed that using trapezoidal current impulse with small initial current or little current rising slope reduced relative wear ratio and material removal rate as well. However, larger relative wear ratio was obtained for workpiece of tungsten carbide when current rising slope was too little. Using the 1st order current impulse with 20 μs current rising time can improve relative wear ratio about 30 % while remain material removal rate the same as rectangular current impulse for tungsten carbide.

In this paper, a lead frame package with trace routing capability is proposed for advanced QFN package that has copper traces to connect with pads or dies, called routable aQFN package. Four packages were conducted to evaluate the trace routing capability. The first is wire bond type 11 mm ×11 mm 141 I/Os package with trace fan-out designs. The second is wire bond type 3.2 mm × 3.2 mm 48 I/Os package with trace fan-in designs. The third is flip chip bond type 8 mm × 8 mm package 288 I/Os with the combination of the trace fan-in and fan-out design. The last is flip chip bond type 6 mm × 6 mm package 25 I/Os with three dies by trace routing to connect die with die and under developing. Compared to aQFN package, a significant improvement in increasing I/Os, reducing wire sweep risk and be more flexible bond layer-out design can be obtained by choosing wire bond type routable aQFN. There are major advantages of flip chip type routable aQFN: more I/Os, multi-dies package and finer pitch bump layer-out. Currently, the trace routing capability is that 0.5mm pitch can escape 2 traces between pad and pad. The minimum line width and trace space is 50 um and 100 um, respectively.

Burkholderia cepacia is a widespread, environmental gram-negative bacillus that is associated with nosocomial infections. This bacterium is considered to be an important pathogen in immunocompromised patients and is inherently resistant to multiple antimicrobial agents. To compare the activity of different antimicrobial agents and the potential of combinations against invasive strains of B. cepacia, we collected 36 isolates of B. cepacia from blood cultures and checked their susceptibilities to 13 antimicrobials by broth microdilution method. Most strains tested were susceptible to minocycline (94.4%), ceftazidime (86.1%), ciprofloxacin (83.3%), and trimethoprim-sulfamethoxazole (83.3%). All strains were resistant to aminoglycosides, and only some strains were susceptible to imipenem (16.7%), aztreonam (19.4%), moxalactam (25.0%), piperacillin (25.0%), and carbenicillin (47.2%). The effects of combinations of ceftazidime with amikacin, ceftazidime with ciprofloxacin, and ciprofloxacin with amikacin were assayed by checkerboard titration method. Synergistic effect was found in 28 out of 36 tested strains (77.8%), when ceftazidime was combined with amikacin, in 25 out of 36 strains (69.4%) when ceftazidime was combined with ciprofloxacin, and in only 8 out of 36 strains (22.2%) when ciprofloxacin was combined with amikacin.

This study investigated the in vitro susceptibilities of methicillin-resistant Staphylococcus aureus (MRSA) to nine antimicrobial agents in Taiwan. A total of 1,725 isolates were obtained from 20 hospitals throughout Taiwan from 2006 to 2010. The minimum inhibitory concentrations (MICs) of the nine agents were determined by the agar dilution method. The MICs of mupirocin and tyrothricin were determined for 223 MRSA isolates collected from 2009 to 2010. For vancomycin, 99.7 % were susceptible; however, 30.0 % (n = 517) exhibited MICs of 2 μg/ml and 0.3 % (n = 6) demonstrated intermediate susceptibility (MICs of 4 μg/ml). Nearly all isolates (≥ 99.9 %) were susceptible to teicoplanin, linezolid, and daptomycin. The MIC90 values were 2 μg/ml for ceftobiprole and 1 μg/ml for nemonoxacin. The MIC90 values of mupirocin and tyrothricin were 0.12 and 4 μg/ml, respectively. MIC creep was noted for daptomycin during this period, but not for vancomycin, teicoplanin, linezolid, or tigecycline. For isolates with vancomycin MICs of 2 μg/ml, the MIC90 values were 2 μg/ml for teicoplanin, 0.5 μg/ml for daptomycin, and 0.5 μg/ml for tigecycline. Those values were four- to eight-fold higher than those among isolates with vancomycin MICs of 0.5 μg/ml (2, 0.06, and 0.12 μg/ml, respectively). Of the nine MRSA isolates exhibiting non-susceptibility to vancomycin (n = 6), teicoplanin (n = 1), daptomycin (n = 2), or tigecycline (n = 1), all had different pulsotypes, indicating the absence of intra-hospital or inter-hospital spread. The presence of a high proportion of MRSA isolates with elevated MICs (2 μg/ml) and MIC creep of daptomycin might alert clinicians on the therapy for serious MRSA infections in Taiwan.

The purpose of this study is to better define arteriographic selection criteria for living related liver transplantation (LRLT) based on literature review, technical and theoretical considerations, and correlation of patterns of variation in hepatic artery anatomy with recipient and donor outcomes.Visceral angiograms of 92 consecutive living related liver transplant donors were retrospectively reviewed by two radiologists and one transplant surgeon. Arterial configurations were categorized. Recipient and donor outcomes were determined by a review of transplant surgery and radiology records.Anomalous hepatic artery anatomy was identified in 67% of potential donors. A left hepatic artery (LHA) with a diameter of less than 2 mm was identified in 1%, and with a diameter of 2-3 mm, in 5%. A dual LHA supply to the left lateral segment was identified in 11%. Two subtypes were defined. Bifurcation of the LHA into branches entering segment II and segment III less than 1 cm from the LHA origin was present in 8%. A replaced LHA from the left gastric artery (17%) and complex, aberrant branching of the LHA (4%) were identified. Vital LHA supply to tissue other than the left lateral segment was present in 21%, including the cystic artery as a branch of the LHA (4%), significant supply of the right lobe from the LHA (5%), and large branches from the LHA entering segment IV (13%). All three donors with significant supply of the right lobe from the transplanted LHA had complications.Absolute exclusionary criteria for LRLT are an LHA diameter of less than 2 mm, dual arterial supply to liver segments II and III, indeterminate arterial anatomy, preexisting vascular disease in donor liver, and a significant LHA supply to the right lobe. Relative exclusionary criteria are an LHA diameter of 2-3 mm, early bifurcation of the LHA, and arterial supply of segment 4 exclusively from the LHA.

Polymicrobial bacterial pericarditis with mediastinitis after traumatic endotracheal intubation is an unusual condition. We report a 54-year-old man, a victim of nasopharyngeal carcinoma, who developed pericardial effusion with tamponade after traumatic endotracheal intubation. The diagnosis of polymicrobial bacterial pericarditis was made when pericardiocentesis revealed purulent fluid that grew a mixed culture of anaerobic and aerobic bacteria, reflecting the normal upper airway flora. By bronchoscopic study, a laceration over the lower trachea was detected. The patient received prolonged aggressive antibiotic therapy and pericardial drainage. The infection improved, but the patient later died from another episode of nosocomial infection.

A total of 35 Trichosporon isolates were collected from the Taiwan Surveillance of Antimicrobial Resistance of Yeasts (TSARY) project from 1999 to 2006, and their identifications as well as drug susceptibilities were determined. The most frequently isolated species was T. asahii (62.9%), and the most common clinical sample that yielded Trichosporon isolates was urine (37.1%). The etiology of all seven invasive trichosporonosis was T. asahii. For the 22 T. asahii isolates, the MIC(50) and MIC(90) for amphotericin B were 0.25 and 1 μg/mL, respectively. Those for fluconazole were 2 and 4 μg/mL, respectively, and for voriconazole 0.031 and 0.063 μg/mL, respectively. When the intraclass correlation coefficients (ICCs) and agreements were calculated, we found that the MICs of fluconazole obtained from different methods were similar and the inter-method discrepancies were low. Nevertheless, no unanimous MIC of amphotericin B and voriconazole was obtained among different methods.

This article introduced a type of rapid prototyping (RP) transtibial socket that is fabricated by a fused deposition modeling (FDM) machine and wrapped with a layer of unsaturated polyester resin (UPR) to enhance its flexural strength. As current rapid prototyping machines use a layer-based process to manufacture products, this will result in RP products liable to break along forming layers once bending moment is applied. To prevent RP prosthetic socket from breakage, this study proposed wrapping a layer of unsaturated polyester resin around a preliminary thin RP socket to reinforce its flexural strength. Factors affecting the strength of the resin-reinforced RP socket include thickness and forming orientation of the preliminary RP socket, thickness of the UPR layer, and type of material used to make the preliminary RP socket. Employing Taguchi experimental design method and ASTM three-point bending test standard, the parameters that influence the flexural strength of the resin-reinforced RP prosthetic socket can be determined. Based on the appropriate parameters, including thickness of the RP layer and UPR layer, the RP material and RP fabricating orientation, the preliminary thin RP prosthetic sockets can be fabricated by an FDM machine. And the thin layer preliminary RP sockets were then wrapped with cotton socks and laminated UPR layer to form resin-reinforced RP sockets. To confirm the effectiveness of the resin-reinforced sockets developed in this study, the pressures at residual limb/socket interface were measured by using a pressure distribution measurement system and movement was captured by a motion analysis system while a patient wears the resin-reinforced RP socket. Two resin-reinforced RP sockets have been fabricated and tested by a volunteer amputee. Analysis of the experimental results would assist a prosthetist to assess the distribution of interface pressures at the pressure-tolerant (PT) and pressure-relief (PR) areas of the residual limb. And, the gait pattern will be used to evaluate the applicability while the resin-reinforced RP socket is worn. Trial uses for durability test of the proposed RP socket are being arranged.Copyright © 2010 by ASME

This investigation employed Taguchi experimental design method and ASTM three-point bending test to determine the parameters that influence the flexural strength of a material composed of a thin layer fabricated by a rapid prototyping (RP) machine and coated with a layer of unsaturated polyester resin (UPR). Since current rapid prototyping machines use a layer-based process to manufacture products, this will result in RP products liable to break along forming layers when bending load is applied. A type of resin-reinforced RP transtibial socket is proposed to strengthen the flexural strength so that the abrupt collapse can be prevented if a transtibial prosthetic socket made by an RP machine. This study proposed wrapping a layer of unsaturated polyester resin around a preliminary thin RP socket manufactured by a fused deposition modeling (FDM) machine to reinforce its flexural strength. Factors affecting the strength of the resin-reinforced RP socket include thickness and forming orientation of the preliminary RP socket, thickness of the UPR layer, and type of material used to make the preliminary RP socket. Employing Taguchi experimental design method and ASTM three-point bending test standard, the parameters that influence the flexural strength of the resin-reinforced RP prosthetic socket can be determined. Based on the appropriate parameters, including thickness of the RP layer and UPR layer, the RP material and RP fabricating orientation, the preliminary thin RP prosthetic sockets can be fabricated by an FDM machine. And the thin layer preliminary RP sockets were then wrapped with cotton socks and laminated UPR layer to form resin-reinforced RP sockets. To confirm the effectiveness of the resin-reinforced sockets developed in this study, a volunteer subject with unilateral left below-knee amputation is recruited to implement the experiment. The pressures at residual limb/socket interface were measured by using a pressure distribution measurement system and movement was captured by a motion analysis system while a volunteer patient wears the resin-reinforced RP socket. The experimental results demonstrated that the applicability of the proposed type of material and a resin-reinforced RP transtibial socket has been verified. A prosthetist may use the interface pressures exerting on stump and gait pattern during walking to assess the suitability of this type of RP socket based on clinical expertise. Further trial use and more subjects are needed to validate the durability of the proposed RP socket.Copyright © 2010 by ASME

Identifying patients who may develop acute kidney injury (AKI) remains challenging, as clinical determinants explain only a portion of individual risk. Another factor that likely affects risk is intrinsic genetic variability. Therefore, a systematic review of studies was performed that related the development or prognosis of AKI to genetic variation.MEDLINE, EMBASE, HuGEnet, SCOPUS, and Web of Science were searched for articles from 1950 to Dec 2007. Two independent researchers screened articles using predetermined criteria. Studies were assessed for methodological quality via an aggregate scoring system.The 16 included studies were of cohort or case-cohort design and investigated 35 polymorphisms in 21 genes in association with AKI. Fifteen gene-gene interactions were also investigated in four separate studies. Study populations were primarily premature infants or adults who were critically ill or postcardiac bypass patients. Among the studies, five different definitions of AKI were used. Only one polymorphism, APO E e2/e3/e4, had greater than one study showing a significant impact (P0.05) on AKI incidence. The mean quality score of 5.8/10 (range four to nine), heterogeneity in the studies, and the dearth of studies precluded additional meta-analysis of the results.Current association studies are unable to provide definitive evidence linking genetic variation to AKI. Future success will require a narrow consensus definition of AKI, rigorous epidemiologic techniques, and a shift from a priori hypothesis-driven to genome-wide association studies.

This article proposed a computer-aided engineering process that is to fabricate a prosthetic socket using rapid prototyping technology. Moreover, since current RP machines use a layer-based process to manufacture products, this result in RP products liable to break along layers once bending moment is applied. To prevent RP prosthetic socket from breaking, this study proposes wrapping a layer of unsaturated polyester resin (UPR) around the prosthetic socket to reinforce its strength. Factors affecting the strength of the resin-reinforced RP socket include thickness and forming orientation of the preliminary RP socket, thickness of the UPR layer, and type of material used to make the preliminary RP socket. This study employed Taguchi experimental design method to design a series of test specimens for use by the 3-point bending test. Based on analysis of the results of the bending strength test, the design parameters for a resin-reinforced transtibial socket of appropriate strength can be determined. The preliminary RP socket for a specific transtibial amputee is fabricated using an FDM machine and then wrapped with a reinforcing layer of UPR.

Currently, rapid prototyping (RP) products are manufactured by layer-based process; this result may cause RP products to break easily along layers when a bending moment is applied. To prevent RP transtibial sockets from breaking, wrapping a layer of unsaturated polyester resin (UPR) around transtibial sockets to reinforce its flexural strength is proposed. To verify the applicability of resin-reinforced RP socket fabrication, two experimental systems, including a socket sensor measurement and gait analysis system, are used to obtain interface pressures between stump, socket and gait characteristics during stance phase while such type of prosthetic socket is used. A male volunteer with a left below-knee amputation, a twenty-year transtibial socket user, was selected for this study. In the experiments, sensors were pasted on the stump and measurement data was collected at different walking speeds. The results of these experiments showed that the interface pressures were concentrated on pressure-tolerant areas, and the swing phase and stride length of stump increased while the volunteer was walking at a fast speed. The resin-reinforced rapid prototyping sockets have better comfortable quality of fitting because the interface pressures are more concentrated on pressure-tolerant areas including the patella tendon and medial tibia flare while wearing the new type of sockets.Copyright © 2009 by ASME

Twenty cases of adenoid cystic carcinoma (ACC) and 18 cases of mucoepidermoid carcinoma (MEC), were examined for expression of the Schwann cell markers S100 protein and glial fibrillary acidic protein (GFAP) by immunohistochemical staining. The relationship between expression of S100 and GFAP and the occurrence of perineural invasion was assessed. Ultrastructural localization of S100 and GFAP was examined by immunoelectron microscopy, and the co-expression of S100 and muscle actin by double fluorescence immunostain. Perineural invasion was found in 11 ACCs (55%) and 0 MECs (0%). S100 and GFAP were expressed in most of the ACCs but none of the MECs; the difference in the rate of perineural invasion and expression of S100 and GFAP was significant between ACC and MEC (P

Using an epidemiologically meaningful in-hospital population with community-acquired infections, we evaluated antibiotic therapy in terms of indication and choice of antibiotic and microbiologic work-up.Infectious disease specialists evaluated charts of 436 patients from 9 hospitals and selected those who received antibiotics within 3 days of admission. Each antibiotic prescribed was marked for appropriateness of indication and choice. Microbiologic isolates were evaluated for their clinical significance.The most common infections were in the lower respiratory tract (46.1%). Each patient received a mean of 2.25 antibiotics for 8.1 +/- 6.4 days. Of the 975 courses of antibiotics given in the study period, indication and choice were correct in 37.4% and unsatisfactory in 14.5%. The vast majority of antibiotics used (79.2%) were first-line antibiotics--usually first-generation cephalosporins, aminoglycosides, and aminopenicillins. Most patients (66%) had a microbiology laboratory work-up, but only 37.4% were judged by evaluators to have a meaningful microbiologic diagnosis. Among the 201 patients with lower respiratory tract infections, 105 (52.2%) had a diagnosis of pneumonia. A positive isolate was recovered in 30 (28.6%) patients, and most of these isolates (20, 68.7%) were aerobic gram-negative rods. There were three positive blood cultures but none grew Streptococcus pneumoniae.Antibiotics were used excessively in number and duration. The microbiologic work-up had little effect on the indication and choice of antibiotics. Community-acquired pneumonia differed markedly from that in Western countries in that only 3.3% were caused by S. pneumoniae.

Prostatic abscess is an unusual occurrence in the era of modern antibiotics. We report a rare case of emphysematous prostatic abscess owing to Klebsiella pneumoniae in a 45-year-old man with a 10-year history of alcoholism and a 6-year history of diabetes mellitus. Prostatic abscess is a difficult clinical diagnosis without specific symptoms and signs. Computerized tomography can assist in making the diagnosis of emphysematous prostatic abscess. Definitive treatment is complete surgical drainage and the use of effective antibiotics.

In this study, Ni(P) bond pads joined with Sn solder bumps were stressed with a high current density of 104 A/cm2. Serious electromigration-induced Ni(P) consumption and unusual EM-enhanced diffusion of the interfacial Ni3Sn4 compound layer are observed. However the observed EM-induced Ni(P) consumption and EM-enhanced diffusion of the interfacial Ni3Sn4 compound layer can be effectively retarded by introducing an additional electroless Pd layer on the Ni(P) layer. The improvement in EM resistance due to the Pd layer can be attributed to PdSn4 formation and Pd solutes in the interfacial Ni3Sn4 layer.

For many infectious agents, seroprevalence rate is low but has serious consequences and must therefore be kept out of donated blood supplies. However, screening to ensure the safety of blood supplies has an associated very high cost. For example, in blood banks, detection of all the harmful items in a large number of samples is an expensive and tedious process. The laboratory and statistical approaches to obtain significant savings by the pooling method were discussed from 1943, recently, there have been further discussions of pooling sera as a means to determining the HIV seroprevalence rate in the general population or the weed out all HIV-positive individuals in blood screening. Here we describe a simple mathematical method to weed out all HIV, and HCV seropositive units. The method is designed to maximize possible savings. Two examples illustrate the application of this method in determining the number to be pooled in each stage, and the resulting savings. When the prevalence rate is lower than 2 percent. our method offers savings of over 80 percent.

Experiments were performed on 64 cats anesthetized with chloralose-urethane, paralyzed and artificially ventilated. Electrical stimulation of locus coeruleus (LC) elicited increases in BP, HR, LVSP, dP/dt max and RNA. Buffer nerve section had no effect on the increase of these parameters, but could prolong the time of rise of BP and recovery phases. Injection of L-glutamate into LC, on the other hand, could decrease BP, HR, LVSP and dP/dt max. Intra-LC injection of kainic acid could also decrease BP. When the LC neurons showed degeneration or depolarization block after kainic acid injection, electrical stimulation of the LC could still elicit marked pressor response. The results suggest that the pressor response induced by electrical stimulation of LC might be mediated by the fibers passing through LC, while activation of LC neurons themselves would result in the depressor response.

We describe a case in which we employed a new method of using intraluminal balloon support for direct percutaneous placement of a jejunostomy tube. Standard interventional radiologic techniques and readily available equipment and materials were used.

Perinatal mortality rate is closely related to birth weight. We collected data on 35919 single liveborn babies at a teaching hospital in central Taiwan between 1977 and 1987, excluding 1980. The average birth weights of the two sexes combined, and of male and female live births separately, were 3163 +/- 486 gm, 3211 +/- 499 gm (N = 18865) and 3110 +/- 466 gm (N = 17054), respectively. The average gestational age of these live births was 39.7 +/- 2.1 weeks. The skewness and kurtosis of birth weight and gestational age distribution were -0.86 and 3.13, and -2.11 and 10.29, respectively. The two distributions indicated high kurtosis and left skewness, and were approximately normally distributed. Because birth weight and gestational age are highly associated, the skew-to-left residual distribution of birth weight might have been induced by low gestational age. Babies of low gestational age might not be able to develop mature organs and tissues, which, thus, results in high perinatal mortality. The distribution of birth weight intersects the normal curve within the region between 1500 gm and 2000 gm, which means that we may divide it into a predominant part and a residual part. Many articles have shown that the residual part is highly correlated to perinatal mortality rate and deserves further analysis. The average birth weight with gestational age at 40 weeks was 3239 +/- 385 gm, skewness and kurtosis were 0.16 and 0.75, respectively. The birth-weight distribution for a given number of gestational weeks is closer to the normal distribution. This paper provides standard figures and tables of birth weight with specific gestational age as a norm for related medical research.

We report on the field emission from self-assembled silicon nanostructures fabricated on n-type silicon (100) substrates using electron beam annealing. Arrays of nanostructures with an average height of 8nm were formed by substrate annealing at 1100°C for 15s. Simple field emission diode structures were fabricated using these nanostructured silicon substrates as cathodes separated from an aluminium anode by a 1μm thick layer of photoresist. The dielectric leakage current was less than 0.4nA which was found to be a negligible component of the field emitted current flowing through the diode. Following conditioning, the Si nanostructure field emission characteristics become stable and reproducible with Fowler–Nordheim tunneling occurring for fields as low as 3.2Vμm−1. At higher fields, current saturation effects are observed with current-field characteristics typical of space charge limited conduction. The low voltage operation of this device results in suppression of ionizing electron–molecule collisions an...