A Convenient and Effective Preoxygenation Technique for Prolonging Deep Inspiration Breath-Hold Duration With a Venturi Mask With a 50% Oxygen Concentration.

PURPOSE: Voluntary deep inspiration breath-hold (DIBH) is commonly used in radiation therapy (RT), but the short duration of a single breath-hold, estimated to be around 20 to 40 seconds, is a limitation. This prospective study aimed to assess the feasibility and safety of using a simple preoxygenation technique with a Venturi mask to prolong voluntary DIBH. METHODS AND MATERIALS: The study included 33 healthy volunteers and 21 RT patients. Preoxygenation was performed using a Venturi mask with a 50% oxygen concentration. Paired t tests compared the duration of a single DIBH in room air and after 5, 15, and 30 minutes of preoxygenation in healthy volunteers. Sustainability of breath-hold and tolerability of heart rate and blood pressure were assessed for multiple DIBH durations in both volunteers and patients. RESULTS: In healthy volunteers, a 15-minute preoxygenation significantly prolonged the duration of a single DIBH by 24.95 seconds compared with 5-minute preoxygenation (89 ± 27.76 vs 113.95 ± 30.63 seconds; P < .001); although there was a statistically significant increase in DIBH duration after 30-minute preoxygenation, it was only extended by 4.95 seconds compared with 15-minute preoxygenation (113.95 ± 30.63 vs 118.9 ± 29.77 seconds; P < .01). After 15-minute preoxygenation, a single DIBH lasted over 100 seconds in healthy volunteers and over 80 seconds in RT patients, with no significant differences among 6 consecutive cycles of DIBH. Furthermore, there were no significant differences in heart rate or blood pressure after DIBHs, including DIBH in room air and 6 consecutive DIBHs after 15-minute preoxygenation (all P > .05). CONCLUSIONS: Preoxygenation with a 50% oxygen concentration for 15 minutes effectively prolongs the duration of 6 cycles of DIBH both in healthy volunteers and RT patients. The utilization of a Venturi mask to deliver 50% oxygen concentration provides a solution characterized by its convenience, good tolerability, and effectiveness.

Robiginitalea aurantiaca sp. nov. and Algoriphagus sediminis sp. nov., isolated from coastal sediment.

Two novel rod-shaped, Gram-stain-negative, aerobic and non-motile bacterial strains, designated M39T and C2-7T, were isolated from the coastal sediment of Xiaoshi Island, Weihai, PR China. Growth of strain M39T occurred at 15-37 °C, at pH 6.0-9.0 and in the presence of 1.0-9.0 % (w/v) NaCl. Strain C2-7T grew at 15-40 °C, at pH 6.0-8.0 and in the presence of 0.5-8.0 % (w/v) NaCl. Phylogenetic analysis based 16S rRNA gene sequences revealed that strains M39T and C2-7T belong to the phylum Bacteroidota. Based on the results of 16S rRNA gene sequence analysis, the closest relative of strain M39T was Robiginitalea marina KCTC 92035T (95.4 %), and the closest relative of strain C2-7T was Algoriphagus namhaensis DPG-3T (97.0 %). The percentage of conserved protein and average nucleotide identity values between strain M39T and some species of the genus Robiginitalea were 66.9-77.6% and 69.3-71.0 %, respectively, while those between strain C2-7T and some species of the genus Algoriphagus were 68.0-70.1% and 56.1-72.6 %, respectively. The major cellular fatty acids (>10 %) of strain M39T consisted of iso-C15 : 1 F, iso-C15 : 0 and iso-C17 : 0 3-OH, while those of strain C2-7T were iso-C15 : 0 and C16 : 1 ω7c/C16 : 1 ω6c. MK-6 was the only respiratory quinone that was compatible with the genus of strain M39T. The predominant menaquinone of strain C2-7T was MK-7. The major polar lipids of strain M39T were phosphatidylethanolamine and glycolipids, and those of strain C2-7T were phosphatidylethanolamine, one unidentified aminolipid and four unidentified lipids. The DNA G+C contents of strains M39T and C2-7T were 46.9 and 40.8 mol%, respectively. Based upon the results presented in this study, strains M39T and C2-7T represent novel species of the genera Robiginitalea and Algoriphagus, respectively, for which the names Robiginitalea aurantiaca sp. nov. and Algoriphagus sediminis sp. nov. are proposed with the type strains M39T (=MCCC 1H00498T=KCTC 92014T) and C2-7T (=MCCC 1H00414T=KCTC 92027T).

Brumimicrobium oceani sp. nov., isolated from coastal sediment saline lake and environmental adaptability analysis.

A novel Gram-stain-negative, aerobic, non-motile, rod-shaped and orange-colored bacterium, designated as strain C305T, was isolated from marine sediment of the coast area of Weihai, China. Strain C305T growth occurs at 4-40 °C (optimally at 30-33 °C), pH 6.0-9.0 (optimally at pH 8.0) and with 0.5-10.0% (w/v) NaCl (optimum 1.5-3.0%). No growth is observed without NaCl. The major cellular fatty acids of strain C305T were identified as iso-C15:0, iso-C15:1G and iso-C17:0 3-OH. The major respiratory quinone was found to be MK-6, and the DNA G + C content was determined to be 35.5 mol%. The predominant polar lipids were mainly phosphatidylethanolamines (PE), unidentified aminophospholipids (APL), andunidentified lipid (L2). Phylogenetic analysis based on 16S rRNA gene sequences revealed that C305T was a member of the genus Brumimicrobium and had a 16S rRNA gene sequence similarity values of 96.9-98.0% with recognized Brumimicrobium species. On the basis of the phylogenetic and phenotypic evidences, strain C305T represents a novel species of the genus Brumimicrobium, for which the name Brumimicrobium oceani sp. nov. is proposed. The type strain is C305T (= KCTC 62371 T = MCCC 1H00297T).

Winogradskyella vincentii sp. nov. and Winogradskyella alexanderae sp. nov., two novel bacteria isolated from intertidal sediment.

Two novel Gram-stain-negative, facultative anaerobic, chemoheterotrophic, non-motile and rod-shaped strains were isolated from intertidal sediment sampled at Xiaoshi Island, Weihai, PR China. Full sequence analysis of the 16S rRNA genes showed that the two strains were closely related to members of the genus Winogradskyella and the phylogenetic similarities to their closest relative, Winogradskyella aquimaris, were 96.7 and 95.8 %, respectively. The DNA G+C contents of strains 2Y89T and D23T were 33.3 and 35.1 mol%, respectively. The respiratory quinone detected in both strains was MK-6. The major fatty acids detected in strain 2Y89T were iso-C15 : 0 and iso-C15 : 1G, and in strain D23T they were iso-C15 : 1G, iso-C15 : 0 and iso-C17 : 03-OH. The principal polar lipids of strain 2Y89T mainly included phosphatidylethanolamine, aminoglycolipids, unidentified aminolipids, unidentified glycolipids and unidentified lipids; strain D23T was the same as strain 2Y89T except that it did not contain aminoglycolipids. Based on the phenotypic, chemical taxonomic, genotypic and phylogenetic features established in this study, we suggest that the new strains represent two novel species of the genus Winogradskyella, for which the names Winogradskyella vincentii sp. nov. (type strain 2Y89T=MCCC 1H00477T=KCTC 92034T) and Winogradskyella alexanderae sp. nov. (type strain D23T=MCCC 1H00462T=KCTC 92023T) are proposed.

[Variation Characteristics of Exogenous Cadmium with Different Contents in Red Soil].

To investigate the change characteristics of exogenous cadmium (Cd) into red soil over time, different concentrations of Cd (0, 0.3, 2.0, 5.0, 10, 30, 60, and 100 mg·kg-1) were added to farmland soil, and samples were taken at the 3rd, 7th, 14th, 28th, 42th, 56th, 70th, and 84th day, respectively. The occurrence of Cd in farmland soil was analyzed using the BCR hierarchical extraction method, and the stabilization and distribution characteristics of Cd in farmland soil were simulated by three dynamical models. The results showed that:① After exogenous Cd entered the soil, the soil Cd form was redistributed, tending to the original soil Cd form distribution characteristics, the binding strength of Cd and soil increased as time increased, and the total redistribution coefficient gradually tended to 1. ② Stabilization of exogenous Cd in red soil was a long-term process. The extractable state of weak acid gradually transformed to the other three forms and finally to the residue state. Within 84 days, the oxidation state at 0.3 mg·kg-1 gradually decreased with time, and the other concentrations showed the opposite. Within 84 days, when the reducible state was below 30 mg·kg-1, it gradually decreased with time, and the other concentrations showed the opposite. ③ The stabilization process of exogenous Cd in red soil was mainly a diffusion process controlled by multiple reaction mechanisms. The higher the concentration of exogenous Cd, the higher the change rate of the residual state. These research results can provide theoretical basis for the related research based on exogenous cadmium and the risk control and remediation of soil contaminated with heavy metals.

Interaction of genotype-ecological type-plant spacing configuration in sorghum [Sorghum bicolor (L.) Moench] in China.

Grain sorghum has been a significant contributor to global food security since the prehistoric period and may contribute even more to the security of both food and energy in the future. Globally, precise management techniques are crucial for increasing grain sorghum productivity. In China, with diverse ecological types, variety introduction occasionally occurs across ecological zones. However, few information is available on the effect of ecological type on genotype performance and how plant spacing configuration influences grain yield in various ecological zones. Hence, a series of two-year field experiments were conducted in 2020 and 2021 in four ecological zones of China, from the northeast to the southwest. The experiments included six widely adapted sorghum varieties under six plant spacing configurations (two row spacing modes: equidistant row spacing (60 cm) mode and wide (80 cm)-narrow (40 cm) row spacing mode; three in-row plant spacings: 10 cm, 15 cm, and 20 cm). Our results indicated that ecological type, variety, and plant spacing configuration had a significant effect on sorghum yield. Ecological type contributed the highest proportion to the yield variance (49.8%), followed by variety (8.3%), while plant spacing configuration contributed 1.8%. Sorghum growth duration was highly influenced by the ecological type, accounting for 87.2% of its total variance, whereas plant height was mainly affected by genotype, which contributed 81.6% of the total variance. All test varieties, developed in the south or north, can reach maturity within 94-108 d, just before fall sowing in central China. Generally, sorghum growth duration becomes longer when a variety is introduced from south to north. A late-maturing variety, developed in the spring sowing and late-maturing regions, possibly could not reach maturity in the early-maturing region. The row spacing modes had no significant affect on sorghum yield, but the equal-row spacing mode consistently caused higher yields with only one exception; this might imply that equal-row spacing mode was more advantageous for boosting sorghum yield potential. In contrast, decreasing in-row plant spacing showed significant positive linear associations with sorghum grain yield in most cases. In addition, these results demonstrated that sorghum is a widely adapted crop and enables success in variety introduction across ecological zones.

[Potential of Accumulation and Application of Dominant Plants in Lanping Lead-zinc Mine, Yunnan Province].

A field investigation in the abandoned lead-zinc mines in Yunan Province was conducted to assess the accumulation potential of dominant plant species and six heavy metals in mine soils. Eighteen types of plants were selected for the analysis. Local plants and soil were sampled and analyzed for cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), and Zn (zinc) concentrations. Bioconcentration and translocation factors were calculated. Cluster analysis was performed to calculate the accumulation potential. The results showed that all dominant plants (18 species and 13 families) were herbaceous plants. The content of heavy metals in these plants was higher than their normal content in plants. The above-ground Cd content of Corydalis yanhusuo, Carum bretschneideri, and Picris hieracioides reached 62.29, 76.49, and 85.09 mg ·kg-1. The bioconcentration factors of Cd in these three plants were 0.57, 0.58, and 0.66, and the translocation factors were 0.89, 0.45, and 1.48, respectively. These plants have a strong ability to absorb and transfer Cd in soil; hence, they have the potential to remediate the Cd-contaminated soil. The above-ground Cd content of Euphorbia fischeriana and Cynoglossum amabile were 0.46 mg ·kg-1and 0.23 mg ·kg-1, respectively, and the bioconcentration factors were less than 0.01. These two plants accumulate low levels of heavy metals and thus, are suitable for growth in high altitude areas of Southwest China. They are considered economic plants for safe use in Cd-contaminated farmlands and have high application value. To protect the ecological environment of the mining areas, the other 13 plants having good tolerance to heavy metal pollution can be used as vegetation restoration plants in mining areas.

[Remediation Potential of Ageratum conyzoides L. on Cadmium Contaminated Farmland].

To evaluate the remediation potential of Ageratum conyzoides L. on cadmium (Cd) contaminated farmland soil, the Cd-containing plants and root were collected and analyzed by field investigation, original pot experiment, and field experiment. The enrichment factor and removal rate of Ageratum conyzoides L. was calculated. The results showed that the maximum Cd content in the leaves of Ageratum conyzoides L. growing in soil of different lead-zinc mines was 77.01 mg·kg-1. In the high-concentration Cd soil treatment (T2), Cd content of the above-ground of Ageratum conyzoides L. was 69.71mg·kg-1, and Cd enrichment coefficient was 6.09. In the low-concentration Cd soil treatment (T1), the enrichment characteristics of Cd (Ageratum conyzoides L.) are consistent with the enrichment characteristics of Cd under high concentration conditions. Ageratum conyzoides L. exhibits stable accumulation characteristics for Cd. In the field experiment, the average Cd content of Ageratum conyzoides L. was 21.13 mg·kg-1, and the enrichment coefficient was 6.93. The removal rate of the three planting Ageratum conyzoides L. per mu of soil using the Ageratum conyzoides L. to repair Cd contaminated soil was 13.2%-15.6%. The use of Ageratum conyzoides L. to repair Cd pollution in farmland has a good prospect for engineering application.

[Analysis of Characteristics and Sources of Heavy Metals in Farmland Soils in the Xijiang River Draining of Guangxi].

In order to determine the distribution characteristics of heavy metal pollution in farmland soils and related influencing factors in the Xijiang River Basin, 2187 farmland soil samples were collected and their heavy metal contents were tested. The spatial structure and distribution characteristics of heavy metal elements were studied using a combination of geostatistics theory and GIS spatial interpolation. The potential ecological risk index was employed for risk assessment. Multivariate statistical methods, such as correlation analysis and principal component analysis, were used to analyze heavy metal sources. Results showed that farmland soils in the Basin were enriched with seven kinds of heavy metal to some extent, with Cd accumulation being the most evident. T-test independent samples results showed significant differences in heavy metal content between dry and field paddy soils (P<0.05). Cd content in paddy soils was significantly higher than in corresponding dry land soils. Cd in farmland soils in Xijiang River exhibited higher potential ecological risk. Correlation analysis and principal component analysis showed that enrichment of Pb, Zn, As, Cd, and Cu in soil was due to anthropogenic factors such as mining activities, traffic, and sewage irrigation, while Ni and Cr were influenced by natural factors, such as soil parent material. High-content areas of As, Cd, Pb, Zn, and Cu in the upper reaches of the basin are all distributed in the Diaojiang River basin and the Dahuanjiang River basin. Cd was most widely distributed. The most intensive sampling sites indicated that mining activities have caused some degree of heavy metal pollution in local farmland soils.