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Objectives: In view of the concern expressed about the current references, new references for fetal biparietal diameter and head circumference should be constructed for contemporary local populations.Methods: We conducted a retrospective cross-sectional study in two hospitals in Guangdong, Southern China. Fetal biparietal diameter and head circumference percentiles regression were fitted using Cole's LMS method. The BPD and HC data were then transformed into Z-scores that were calculated using two series of reference equations obtained from two methods: Cole's LMS method and the original "mean and SD method." Each Z-score distribution was presented as the mean and standard deviation. Finally, the sensitivity and specificity of each reference for identifying fetuses 97.5th percentile (based on the observed distribution of Z-scores) were calculated. The misclassified number and Youden's index were listed.Results: A total of 17,974 biparietal diameter and 18,269 head circumference measurements were chosen to establish a reference chart. The LMS method could fit the local population better than the "mean and SD method" as it had a lower number of misclassified fetuses and a higher Youden's index.Conclusion: The Cole's LMS method was able to construct a satisfied reference range of fetal head sizes in Southern China.

Ferroelectric HfO₂ attracts a huge amount of attention not only for memory and negative capacitance, but also for programmable logic including memory-in-logic and neuromorphic applications. However, the understanding of material fundamentals still needs to be improved. This paper gives material fundamentals and new insights to this ferroelectric material for future device applications. In particular, the key role of dopants, effects of the interface on the ferroelectric phase, and a detailed discussion of the switching kinetics are of central focus. Based on material properties newly obtained, we discuss opportunities of ferroelectric HfO₂ for device applications.

DC/DC converters are a key part of flexible DC distribution networks and have developed rapidly in recent years. In order to expand the voltage level of the original side of the converter, reduce the disadvantages of high manufacturing cost and large unit volume, this paper studies a modular multilevel converter structure. For the new structure, an optimized double phase-shift voltage balancing control strategy is proposed. Under the double phase-shift control, the NLM algorithm is adopted for the high switching frequency of the voltage balancing control. The 5-level single-phase structure MMC simulation model is built by the simulation platform to verify the feasibility of the proposed structure and control scheme for voltage balancing, and the IGBT switching frequency is compared under the two voltage balancing control methods before and after optimization. The results show that the optimized double phase-shift control strategy can effectively reduce the number of IGBT switching and reduce the switching loss under the condition of modular multilevel converter capacitor voltage balancing.

Background and Objective: Both induction chemotherapy (IC) followed by concurrent chemoradiotherapy (CCRT; IC+CCRT) and CCRT plus adjuvant chemotherapy (AC; CCRT+AC) are standard treatments for advanced nasopharyngeal carcinoma (NPC). However, no prospective randomized trials comparing these two approaches have been published yet. We conducted this network meta-analysis to address this clinical question. Method: We recruited randomized clinical trials involving patients with advanced NPC randomly allocated to IC+CCRT, CCRT+AC, CCRT, or radiotherapy (RT) alone. Pairwise meta-analysis was first conducted, then network meta-analysis was performed using the frequentist approach. Effect size was expressed as hazard ratio (HR) and 95% confidence interval (CI). Results: Overall, 12 trials involving 3,248 patients were recruited for this study, with 555 receiving IC+CCRT, 840 receiving CCRT+AC, 1,039 receiving CCRT, and 814 receiving radiotherapy (RT) alone. IC+CCRT achieved significantly better overall survival ([HR], 0.69; 95% [CI], 0.51-0.92), distant metastasis-free survival (HR, 0.58; 95% CI, 0.44-0.78), and locoregional recurrence-free survival (HR, 0.67; 95% CI, 0.47-0.98) than CCRT. However, survival outcomes did not significantly differ between IC+CCRT and CCRT+AC, or between CCRT+AC and CCRT arms for all the endpoints. As expected, RT alone is the poorest treatment. In terms of P-score, IC+CCRT ranked best for overall survival (96.1%), distant metastasis-free survival (99.0%) and locoregional recurrence-free survival (87.1%). Conclusions: IC+CCRT may be a better and more promising treatment strategy for advanced NPC; however, head-to-head randomized trials comparing IC-CCRT with CCRT-AC are warranted.

One new meroterpenoid-type alkaloid, oxalicine C (1), and two new erythritol derivatives, penicierythritols A (6) and B (7), together with four known meroterpenoids (2&ndash, 5), were isolated from the marine algal-derived endophytic fungus Penicillium chrysogenum XNM-12. Their planar structures were determined by means of spectroscopic analyses, including UV, 1D and 2D NMR, and HRESIMS spectra. Their stereochemical configurations were established by comparing the experimental and calculated electronic circular dichroism (ECD) spectra for compound 1, as well as by comparison of the optical rotations with literature data for compounds 6 and 7. Notably, oxalicine C (1) represents the first example of an oxalicine alkaloid with a cleaved &alpha, pyrone ring, whereas penicierythritols A (6) and B (7) are the first reported from the Penicillium species. The antimicrobial activities of compounds 1&ndash, 7 were evaluated. Compounds 1 and 6 exhibited moderate antibacterial effects against the plant pathogen Ralstonia solanacearum with minimum inhibitory concentration (MIC) values of 8 and 4 &mu, g/mL, respectively. Compound 6 also possesses moderate antifungal properties against the plant pathogen Alternaria alternata with a MIC value of 8 &mu, g/mL.

Supplementary material, approximately 279 KB.

The following paper outlines China National Coal program for tramp metal removal with detail explanation of the evaluation, development and implementation of very strong electro magnets. For the readers' benefit, to give a perspective of relative size and performance, this study includes the familiar scale of magnets, or routine magnets, and then expands into two significantly stronger magnets that have been less commonly used. The performance data on these three magnets prove convincingly, routine magnets for these coal terminal applications are undersized and have typically under-protected high volume conveyors.

There are serious vibration and noise in the pipes of cooling circle in Reactor Cavity and Spent Fuel Pit Cooling and Treatment System (PTR) system during the commissioning test of a Nuclear Power Plant Unit 1, after the improvement of the cooling ability for PTR was actualized. It has been confirmed that the orifice cavitations is the cause of vibration and noise. Engineering modification plans have been proposed: add the series number of throttle orifices and decrease pressure drop of each throttle orifices. Proper engineering redundancy shall be considered according to the test phenomenon and data to keep the orifices from the zones of cavitations. The field investigations after the modification shows that the vibration and noise have been controlled in the acceptable limit while both system function and structure integrity meet the requirement of design code. Thus it can be said that the system modification is successful.Copyright © 2013 by ASME

A direct electrochemical DNA biosensor based on zero current potentiometry was fabricated by immobilization of ssDNA onto gold nanoparticles (AuNPs) coated pencil graphite electrode (PGE). One ssDNA/AuNPs/PGE was connected in series between clips of working and counter electrodes of a potentiostat, and then immersed into the solution together with a reference electrode, establishing a novel DNA biosensor for specific DNA detection. The variation of zero current potential difference (Δ E zcp ) before and after hybridization of the self-assembled probe DNA with the target DNA was used as a signal to characterize and quantify the target DNA sequence. The whole DNA biosensor fabrication process was characterized by cyclic voltammetry and electrochemical impedance spectroscopy with the use of ferricyanide as an electrochemical redox indicator. Under the optimized conditions, Δ E zcp was linear with the concentrations of the complementary target DNA in the range from 10 nM to 1 μM, with a detection limit of 6.9 nM. The DNA biosensor showed a good reproducibility and selectivity. Prepared DNA biosensor is facile and sensitive, and it eliminates the need of using exogenous reagents to monitor the oligonucleotides hybridization.

To assess the long-term outcomes of percutaneous retrogasserian glycerol rhizotomy (PRGR) in patients with medically unresponsive idiopathic trigeminal neuralgia.A total of 3370 patients undergoing PRGR between 1983 and 2003 in our hospital were followed up for 13.1 years (range 3-23 years), and the outcomes were investigated.Of the 3370 patients, 99.58% had complete initial pain relief. A total of 2750 patients were followed up when 112 died of unrelated causes and 508 were lost to follow up. Of the 2750 patients, 962 (35%) had pain recurrence at various intervals: 0.3% in 1 year; 21% in 1 to 5 years; 7% in 5 to 10 years; 4% in 10 to 15 years and 3% in 15 to 23 years. The major complication was facial numbness, among which hypesthesia outweighed hypalgesia. Most patients recovered within half a year, although 109 patients (3.96%) developed permanent mild hypesthesia. There was no anesthesia dolorosa or surgery related mortality in this series.PRGR is a minimally invasive and simple procedure yielding a favorable outcome for trigeminal neuralgia. The major complications of this procedure are reversible within various time intervals. It may serve as a first-line surgical modality for patients unresponsive to pharmacotherapy.