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Background: Streptococcus agalactiae is a recognized pathogen that primarily affects infants and pregnant women. However, its increasingly important role in causing invasive infections among non-pregnant adults has become a significant health concern due to the severity and variety of its clinical impacts. Methods: Nonduplicate S. agalactiae clinical strains associated with clinical infections (n = 139) were isolated from non-pregnant adults in Shandong, China. Antibiotic susceptibility testing, whole-genome sequencing and genomic analyses were conducted to characterize the genome and identify resistance features of these strains. Results: The strains exhibited universal susceptibility to penicillin, ampicillin, cefotaxime, meropenem, linezolid and vancomycin. Notably, high resistance rates were observed for erythromycin (91.4%), clindamycin (89.2%), levofloxacin (84.2%), tetracycline (54.0%) and, to a lesser extent, chloramphenicol (12.9%). Serotyping revealed seven serotypes and one non-typeable strain. Serotypes Ia, Ib, III and V predominated, representing 95.7% of the strains. Nineteen sequence types were categorized into seven clonal complexes, with CC10 being the most prevalent at 48.9%. The resistance genes mreA (100%), ermB (70.5%) and tetM (46.0%) were commonly detected. All the isolates carried at least one pilus backbone determinant and one alpha-like protein gene, with the PI-1+PI-2a and the bca gene being the most frequent at 84.2% and 54.7%, respectively. Conclusions: While S. agalactiae strains in non-pregnant adults retain sensitivity to β-lactam antibiotics, the elevated resistance to erythromycin, clindamycin, levofloxacin and tetracycline is concerning. Given the growing elderly population worldwide, the burden of S. agalactiae infections is significant. Continuous surveillance of serotype distribution and antibiotic resistance patterns is imperative for targeted prevention and therapeutic strategies.

It is of significance to reveal the low-cycle fatigue deformation mechanism of titanium alloy with tri-modal microstructure for improving its properties. This work developed a crystal plasticity finite element model based on realistic microstructure to predict the low-cycle fatigue behavior of TA15 titanium alloys with tri-modal microstructure containing primary α (αp), secondary lamellar α (αl) and transformed β (βt). During modelling, plastic strain accumulation (PSA) and energy dissipation were used as the fatigue indicator parameter (FIP) to predict fatigue damage and life. It is found that the fatigue deformation prefers to localize at the interfaces of αp/β, αl/β and at triple junctions, which leads to the initiation of fatigue crack. In addition, the soft geometry of αl will also contribute to the strain localization inside αl grains causing fatigue damage. This is because the local lattice rotation is more prone to occur at these locations due to the tension-compression asymmetry of lattice rotation, which induces the occurrence of the microtexture and aggravates the heterogeneity of the lattice rotation, leading to the localized PSA and the total energy dissipation. And the asymmetry of lattice rotation in each cycle also leads to the tension-compression asymmetry of flow behavior. Both of the two FIPs can effectively predict fatigue life. With the strain amplitude increasing, the PSA-based model shows a relatively higher predictive accuracy of fatigue life than that of the accumulated energy dissipation-based model. The predicted fatigue life is in accordance with the C-M model.

The goal of this study was to determine how the date of harvest impacts the quality characteristics of Aronia mitschurinii (A. K. Skvortsov and Maitul.) ‘Viking’ and ‘Galicjanka’ berries. Aronia berries were collected from farms in the Midwestern and Northeastern United States over seven weeks of harvest during 2018, 2019 and 2020. The berries were analyzed for total phenol, anthocyanins, proanthocyanins, sugar, and acid. Aronia berry composition modestly deviated between each year of the study. Berries harvested in 2018 had the highest total phenols and proanthocyanidins, both increasing in content from weeks 1–5 from 15.90 ± 3.15–19.65 mg gallic acid equivalents/g fw, a 24% increase, and 2.22 ± 0.40–2.94 mg (+)-catechin equivalents/g fw, a 32% increase, respectively. Berries harvested in 2019 had the lowest total phenol and proanthocyanidin levels and had increasing anthocyanins until week 4. In 2020, aronia berry proanthocyanidins differed from those in 2018 by having 38% lower levels after the 4th week. Across years, berries had increasing °Brix, °Brix: acid, and pH throughout the seven weeks of harvest. Additionally, all years had slight, but statistically insignificant decreases in acidity over the harvest period. Moreover, analysis from berries collected in 2019 suggests no significant difference in quality factors between Viking and Galicjanka aronia cultivars. In conclusion, aronia berry total phenols, proanthocyanidins, pH, and berry size can be significantly affected by the growing year and time of harvest. Acidity was impacted more by growing year than harvest week. In contrast, anthocyanins and °Brix were consistent between years, but influenced considerably by the week of harvest.