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The preparation of fiber-reinforced phosphorus building gypsum composite materials (FRPGCs) is an important approach to enlarge the utilization of phosphogypsum resources. Through reinforcing phosphorus building gypsum (PBG) with basalt fiber (BF), this article probes into the effects of the length and fiber content of BF on the working performance and mechanical properties of basalt-fiber-reinforced phosphorus building gypsum composite materials (BRPGCs) and accesses the toughness of BRPGCs under bending loads using residual strength. The results showed that the addition of BF could significantly promote the mechanical properties of BRPGCs. However, due to the adverse effect of fibers on the working performance of BRPGCs, the fiber content was constrained. After adding 1.2% of 6 mm BF, the bending strength and compressive strength of FRPGCs reached maximum values of 10.98 MPa and 29.83 MPa, respectively. Under a bending load, BRPGCs exhibited an apparent ductile behavior. The P-δ curve presented five stages, with an evident phase of strength stability after cracking. A larger fiber content was conducive to the toughness of BRPGCs. When 1.6% of 6 mm BF was added, the residual strength of FRPGCs could reach 6.77 MPa. [ABSTRACT FROM AUTHOR]

The performance of a coupled oscillator array depends critically on the coupling network. Determination of the optimal coupling phase depends on the oscillator equivalent circuit and the location of mutual coupling between the oscillators. In this paper, the authors examine the effects of coupling phase on the mutual injection locking range. Three element coupled oscillator arrays (COAs) were mutually coupled at two different locations, with each coupling location presenting a different resonance to the coupling network, and the optimal coupling phase required to generate a linear phase shift in the range of -90[degrees] to 90[degrees] was determined. For each coupling location, when the coupling phase was off by 180[degrees], the arrays were shown to lock with a limited range and operate in a mode other than the in-phase mode. Index Terms--Coupling circuits, coupling phase, mutual coupling, voltage controlled oscillators.

The random phase error caused by a statistical free-running frequency distribution in a coupled oscillator array is studied. Analysis shows that the array phase error is closely related to the departure of free-running frequencies of individual oscillators. Phase error is also related to the array size. A closed-form solution to the beam-pointing error in a one-dimensional (1-D) array is derived. Result shows that, for 1-D arrays, the beam-pointing error increases with array size. An analytical solution is also obtained for the side-lobe level of radiation patterns from 1-D arrays. Index Terms--Antenna array, beam-pointing error, coupled oscillator array, phase error.

A novel paper-based bipolar electrode-electrochemiluminescence (pBPE-ECL) switch system was used for the rapid, label-free, and sensitive detection of Hg2+. In the proposed approach, Hg2+ selectively mediates two thymine-enriched single-stranded DNA probes to form double-stranded DNA (dsDNA). In the presence of Hg2+, the 'light-switch' molecule [Ru(phen)2dppz]2+ can freely intercalate into the base pairs of the dsDNA, resulting in intense ECL emission. The assay takes advantage of the wireless pBPE-ECL platform to yield a low-cost, disposable, and sensitive analysis. The system has a limit of 0.1 nM for Hg2+ detection. We also showed that the system can be used to distinguish Hg2+ over other metal ions, including Pb2+, Zn2+, Cu2+, Ba2+, Co2+, Cd2+, Fe3+, Mn2+, and Li+. Moreover, the proposed approach was rapid, low-cost, and label-free for effective sensing of Hg2+ in drinking and lake water. [ABSTRACT FROM AUTHOR]

BACKGROUND In the Genetic Epidemiology Network of Salt Sensitivity (GenSalt) study, we observed that blood pressure (BP) responses to dietary sodium and potassium interventions and the cold pressor test (CPT) varied greatly among individuals. We conducted a replication study to confirm our previous findings among 695 study participants. METHODS The dietary intervention included a 7-day low sodium (51.3 mmol/day), a 7-day high sodium (307.8 mmol/day), and a 7-day high sodium with potassium supplementation (307.8 mmol sodium and 60 mmol potassium/day). BP measurements were obtained during the baseline and each intervention phase. During the CPT, BP was measured before and at 0, 1, 2, and 4 minutes after the participants immersed their right hand in ice water for 1 minute. RESULTS Systolic and diastolic BP responses (mean ± SD (range), mm Hg) were 8.1±8.4 (−39.1 to 18.2) and −3.5±5.1 (−25.1 to 11.1) to low sodium, 9.1±8.4 (−13.3 to 33.1) and 4.0±5.4 (−16.0 to 20.7) to high sodium, and −4.6±5.8 (−31.8 to 11.6) and −1.9±4.3 (−16.9 to 14.2) to potassium supplementation, respectively (all P < 0.0001 for comparison with each former phase). The mean maximum systolic and diastolic BP responses to the CPT were 16.5±10.5 (−15.3 to 63.3) and 7.6±6.1 (−8.7 to 39.3), respectively (all P < 0.0001). CONCLUSIONS Our study indicates that there are large variations in BP responses to dietary sodium and potassium interventions and to the CPT among individuals. [ABSTRACT FROM AUTHOR]

Objective: To investigate the clinical and pathological features of solitary pterygoid benign lesions, as well as the treatment and outcome of endoscopic surgery., Method: We retrospectively analyzed clinical data of 4 patients with pterygoid benign lesions in our department. High resolution CT and enhanced MRI were performed before the operations, then endoscopic surgeries were carried out under the circumstance of general anesthesia. After a follow-up in 12 months to 48 months, nasal endoscopy and MRI examination were performed. Therefore we are able to understand the situation of operations and postoperative recurrences, and to inquire about the changes of symptoms and the relief of symptoms before and after surgery., Result: From the Pathological diagnosis, it showed 2 cases of cystic lesions, 1 case of spindle cell lipoma, 1 case of inflammatory lesion. Postoperative follow up showed scar formation, smooth surface, no recurrence, and no new symptom. Nasal obstruction is relieved after the surgery, and no changes in the sympotoms of headache were observed., Conclusion: The combination of high resolution CT with enhanced MRI isimportant for ascertaining the location, extent and nature of the pterygoid lesions. Endoscopic surgery is a minimally invasive, safe, and effective method for the treatment of solitary pterygoid benign lesions.

Objective: Tetrodotoxin and its analogues (TTXs) were responsible for the poisoning incidents associated with snail Nassarius spp. We studied bacteria isolated from toxic snails as well as their habitat to probe into the relationship between bacteria and toxicity of nassariid gastropod., Methods: Two snail samples were collected from Sheyang, Jiangsu Province on June 13 and 19, 2006, and the toxicity of the snail samples was tested with mouse bioassay method. Bacteria were isolated from the snail samples and from their habitat. A part of isolated bacteria were then cultured in the lab, and TTX in bacteria were screened with an ELISA method., Results: The snails collected were identified as Nassarius semiplicatus, and the toxicity of the 2 samples were 247 mouse unit (MU) and 270 MU / 100 g tissue (wet weight), respectively. TTX was detected in 9 strains among the 14 strains of bacteria isolated from the snail samples and their habitat. TTX content in the toxic strains was very low, which ranged from 15 ng/g to 96 ng/g. Partial of the 16S ribosomal DNA (rDNA) of the toxic strains were then sequenced after PCR amplification, and the toxic strains of bacteria were tentatively identified based on the alignment of these sequences with published data. Toxic strains were closely affiliated with Vibrio, Shewanella, Planococcus, Marinomonas, Photobacterium., Conclusion: These findings suggested that TTX-producing bacteria may play an important role in TTX production or accumulation in nassariid gastropod.