169 research outputs found
Extremal digraphs on Meyniel-type condition for hamiltonian cycles in balanced bipartite digraphs
Let be a strong balanced digraph on vertices. Adamus et al. have
proved that is hamiltonian if whenever
and . The lower bound is tight. In this paper, we shall
show that the extremal digraph on this condition is two classes of digraphs
that can be clearly characterized. Moreover, we also show that if
whenever and , then is
traceable. The lower bound is tight.Comment: 16 page
Effect of Soymilk Fermented by Different Lactic Acid Bacteria on Dough Fermentation Characteristics and Steamed Bun Quality
The effects of soymilk fermented with single and mixed (1:1:1) cultures of three strains of lactic acid bacteria (LAB) isolated from sourdough from Fuchun Teahouse in Yangzhou City on the fermentation characteristics of dough and the quality of steamed bun were investigated. The results showed that the acidity and viable bacterial count of soymilk fermented with the mixed culture were 85.06 °T and 9.66 (lg(CFU/mL)), respectively, which were higher than those of the single culture fermented samples. Meanwhile, compared with the control group, the addition of fermented soymilk significantly increased the organic acid content and viable bacterial count of dough. The lactic acid content and viable bacterial count of dough supplemented with Lactobacillus pentosus 203 fermented soymilk were the highest, which were 18.57 mg/g and 8.94 (lg(CFU/g)), respectively. Dough added with Lactobacillus fermentum 202 fermented soymilk had the highest acetic acid content (3.81 mg/g). Compared with control steamed buns, the specific volume, elasticity and height to diameter ratio of four steamed buns supplemented with fermented soymilk were significantly increased, while the hardness and chewiness were significantly decreased. Steamed buns added with mixed-culture fermented soymilk had the highest overall acceptability. A total of 48 volatile flavor substances were detected in the five groups of steamed buns. Among them, the relative contents and types of flavor substances in the mixed culture group were the highest, which were 71.62% and 47, respectively. After being stored at 4 ℃ for 4 days, the moisture loss rate and retrogradation enthalpy of steamed buns added with fermented soymilk were significantly lower than those of the control group; the highest moisture content of 38.53% and the lowest retrogradation enthalpy of 1.00 J/g were found in the mixed culture group. In conclusion, adding fermented soymilk can effectively improve the quality and flavor and delay the aging of steamed buns, this effect being most pronounced with the incorporation of mixed-culture fermented soymilk
Non-invasive in vivo study of morphology and mechanical properties of the median nerve
The current literature studied the median nerve (MN) at specific locations during joint motions. As only a few particular parts of the nerve are depicted, the relevant information available is limited. This experiment investigated the morphological and biomechanical properties of the MN. The effects of the shoulder and wrist motions on MN were explored as well. Eight young healthy female individuals were tested with two-dimensional ultrasound and shear wave elastography (SWE). The morphological and biomechanical properties were examined in limb position 1, with the wrist at the neutral position, the elbow extended at 180°, and the shoulder abducted at 60°. In addition, the experiment assessed the differences among the wrist, forearm, elbow, and upper arm with Friedman’s test and Bonferroni post hoc analysis. Two groups of limb positions were designed to explore the effects of shoulder movements (shoulder abducted at 90° and 120°) and wrist movements (wrist extended at 45° and flexed at 45°) on the thickness and Young’s modulus. Differences among the distributions of five limb positions were tested as well. The ICC3, 1 values for thickness and Young’s modulus were 0.976 and 0.996, respectively. There were differences among the MN thicknesses of four arm locations in limb position 1, while Young’s modulus was higher at the elbow and wrist than at the forearm and upper arm. Compared to limb position 1, only limb position 4 had an effect on MN thickness at the wrist. Both shoulder and wrist motions affected MN Young’s modulus, and the stiffness variations at typical locations all showed a downward trend proximally in all. The distributions of MN thickness and Young’s modulus showed fold line patterns but differed at the wrist and the pronator teres. The MN in the wrist is more susceptible to limb positions, and Young’s modulus is sensitive to nerve changes and is more promising for the early diagnosis of neuropathy
Susceptibilities of Yersinia pestis to Twelve Antimicrobial Agents in China
Streptomycin is the preferred choice for therapy of plague in China and other countries. However, Yersinia pestis exhibiting plasmid-mediated antimicrobial agent–resistant traits had been reported in Madagascar. In this study, we evaluated the susceptibility of traditional or newer antimicrobial agents used for treatment and/or prophylaxis of plague. Following Clinical and Laboratory Standards Institute (CLSI) recommendations, the susceptibility of 12 antimicrobial agents was evaluated by the agar microdilution method in 1,012 strains of Y. pestis isolated from 1943 to 2017 in 12 natural plague foci in China. One clinical Y. pestis isolate (S19960127) was found to be highly resistant to streptomycin, while the strain was still sensitive to other 11 antibiotics, that is, ciprofloxacin, ofloxacin, kanamycin, chloramphenicol, ampicillin, ceftriaxone, cefuroxime, trimethoprim-sulfamethoxazole, tetracycline, spectinomycin and moxifloxacin. The remaining 1,011 Y. pestis strains in this study demonstrated susceptibility to the above-mentioned 12 antimicrobial agents. Antimicrobial sensitivity surveillance of Y. pestis isolates, including dynamic monitoring of streptomycin resistance during various clinical plague treatments, should be carried out routinely
Use of nanomaterials in the pretreatment of water samples for environmental analysis
The challenge of providing clean drinking water is of enormous relevance in today’s human civilization, being essential for human consumption, but also for agriculture, livestock and several industrial applications. In addition to remediation strategies, the accurate monitoring of pollutants in water sup-plies, which most of the times are present at low concentrations, is a critical challenge. The usual low concentration of target analytes, the presence of in-terferents and the incompatibility of the sample matrix with instrumental techniques and detectors are the main reasons that renders sample preparation a relevant part of environmental monitoring strategies. The discovery and ap-plication of new nanomaterials allowed improvements on the pretreatment of water samples, with benefits in terms of speed, reliability and sensitivity in analysis. In this chapter, the use of nanomaterials in solid-phase extraction (SPE) protocols for water samples pretreatment for environmental monitoring is addressed. The most used nanomaterials, including metallic nanoparticles, metal organic frameworks, molecularly imprinted polymers, carbon-based nanomaterials, silica-based nanoparticles and nanocomposites are described, and their applications and advantages overviewed. Main gaps are identified and new directions on the field are suggested.publishe
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Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study
Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat
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Correction to: Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study
The original version of this article unfortunately contained a mistake
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