Effect of Fine Size-Fractionated Sunflower Husk Biochar on Water Retention Properties of Arable Sandy Soil

Biochar application has been reported to improve the physical, chemical, and hydrological properties of soil. However, the information about the size fraction composition of the applied biochar as a factor that may have an impact on the properties of soil-biochar mixtures is often underappreciated. Our research shows how sunflower husk biochar (pyrolyzed at 650 °C) can modify the water retention characteristics of arable sandy soil depending on the biochar dose (up to 9.52 wt.%) and particle size (<50 µm, 50–100 µm, 100–250 µm). For comparison, we used soil samples mixed with biochar passed through 2 mm sieve and an unamended reference. The addition of sieved biochar to the soil caused a 30% increase in the available water content (AWC) in comparing to the soil without biochar. However, the most notable improvement (doubling the reference AWC value from 0.078 m³ m⁻³ to 0.157 m³ m⁻³) was observed at the lowest doses of biochar (0.95 and 2.24 wt.%) and for the finest size fractions (below 100 µm). The water retention effects on sandy soil are explained as the interplay between the dose, the size of biochar particles, and the porous properties of biochar fractions.     

水溶媒剂型在蚊香系列的应用研究

目的用水作为滴加、释放媒介,制作盘式蚊香、电热片蚊香和电热液体蚊香。方法通过溶解-乳化-包裹等加工工艺,研制水溶媒母液,对盘式蚊香、电热片蚊香进行药剂滴加,以及用于电热液体蚊香,并根据国标方法对药效、毒性、稳定性进行了实验研究。结果研制的15%氯氟醚菊酯、15%四氟甲醚菊酯母液,将母液用水稀释,用于制作氯氟醚菊酯、四氟甲醚菊酯盘式蚊香、电热蚊香片和电热液体蚊香;经检测,0.35%水剂盘式蚊香KT50为4.93和4.52 min,电热片蚊香通电8 h后的KT50为2.90和4.53 min,电热液体蚊香通电360 h后的KT50为3.43和3.53 min,模拟现场1 h击倒率除氯氟醚水剂外均达到90%以上,急性毒性试验显示均为低毒级。结论以水代替油作为溶媒,大大减少了煤油的用量,降低了CO2的排放,可以此降低企业成本,实现低能耗、低污染、低排放。     

An Evaluation of the Accuracy of Labeling of Percent Sodium Hypochlorite on Various Commercial and Professional Sources: Is Sodium Hypochlorite from These Sources Equally Suitable for Endodontic Irrigation?

Introduction

The shelf life of sodium hypochlorite (NaOCl) is limited, and a previous article showed that there can be a discrepancy between the expected concentration of free available chlorine (FAC) and the actual FAC concentration in NaOCl solutions intended for endodontic irrigation. The current study investigates the FAC content of domestic and professional NaOCls and evaluates the influences of dilution and storage on FAC concentration.

Methods

First, domestic and professional NaOCls not obtained from manufacturers were iodometrically titrated. Then, NaOCls were diluted with demineralized water or tap water and stored at 4°C or 18°C and analyzed at baseline and 2 and 22 weeks. Statistical analyses included paired samples, independent samples t tests and repeated multivariate analysis of variance. Correlations were calculated with the Pearson or Spearman rank correlation test. A P < .05 was considered significant.

Results

Label specifications of domestic NaOCl were very imprecise (ie, <5% NaOCl). Domestic NaOCl contained 1.8%–3.5% NaOCl (w/v). Professional NaOCl varied from 14.3% relative less FAC than specified on the label to 23.5% relative more FAC than specified. After 22 weeks, the relative average loss of FAC in all conditions was 5.4% FAC (P = .002). Dilution, diluents, or storage temperature had no effect on the decline of FAC caused by aging.

Conclusions

There is a great variation in NaOCl concentrations, with domestic NaOCl being the least accurate. NaOCl can be stored up to 5 months. The FAC concentration of domestic NaOCl is unpredictable, and, therefore, it appears less suitable for clinical application as root canal irrigant.     

Mild degenerative changes of hip cartilage in elderly patients: an available sample representative of early osteoarthritis

This study investigated the cellular and molecular changes which occur in cartilage from adults with femoral neck fracture (FNF) and osteoarthritis (OA), and explored the similarities in hip cartilage obtained from elderly patients and patients with early OA. Femoral heads were retrieved from 23 female patients undergoing total hip arthroplasty (THA). This group included 7 healthy patients with FNF (hFNF), 8 elderly adults with FNF (eFNF), and 8 elderly patients with hip OA (OA). After high-field MRI T2 mapping, osteochondral plugs were harvested from the weight-bearing area of femoral heads for subsequent macroscopic, histologic, and immunochemical evaluation. Additionally, the contents of cartilage matrix were analyzed, and gene expression was detected. The surface of cartilage from hFNF and eFNF patients appeared smooth, regular, and elastic, whereas it showed irregularities, thinning, and defects in OA patients. Elevated T2 values and decreased accumulation of glycosaminoglycans (GAGs) were detected in cartilage from eFNF patients. Furthermore, type I collagen accumulation was slightly increased and type X collagen concentration was obviously elevated in eFNF patients; however, type II collagen distribution and the contents and anisotropy of collagen fibrils in eFNF patients showed no significant changes. Consistent with histology and immunohistochemical results, aggrecan was downregulated and type X collagen was upregulated, while collagens types I and II showed no significant changes in eFNF patients. The cellular and molecular characteristics of hip cartilage in eFNF patients who showed no symptoms of OA were similar to those in patients with mild OA. Thus, eFNF cartilage can serve as a comparative specimen for use in studies investigating early OA.     

Proposal of a flow scheme for the chemical-form-based quantitative analysis of chlorine compounds in pulp for sanitary products and verification of safety

To determine the amounts and chemical forms of chlorine compounds in elemental chlorine-free (ECF) bleached pulp for sanitary products, a chemical-form-based quantitative analysis flow scheme was created. The scheme involves quantitative determination of compounds eluted in elution tests assuming dermal exposure. The results indicated that most of the chlorine compounds in pulp used for sanitary products were insoluble organically bound chlorine and water-soluble chlorides consisting of chloride ions. The total amount of chlorine obtained by analysis of the total chlorine in the pulp products was close to the sum of the amounts of water-soluble chlorides, residual chlorine, chloroacetic acids, and insoluble organically bound chlorine. Therefore, the balance of chlorine measured by the flow scheme was acceptable. Little residual chlorine was detected in the pulp products, suggesting that the chlorine dioxide used for bleaching was almost completely converted into inactive inorganic chlorides and organic chlorine compounds and that these substances do not affect the health risk posed by pulp products. A risk assessment of the detected chloroacetic acid and dichloroacetic acid revealed that there is no concern about the health risk posed by use of these products.     

Minimally Invasive Treatment for Papillae Deficiencies in the Esthetic Zone: A Pilot Study

Background: The presence of papillary deficiencies adjacent to dental implants or teeth presents an esthetic concern for the dental team and patients. Purpose: The aim of this pilot project is to evaluate a new method for reducing or eliminating small papillary deficiencies. The use of a commercially available gel was evaluated as a possible method for enhancing deficient papillae. Materials and Methods: Eleven patients, seven females and four males, with an average age of 55.8 years (ranging from 25 to 75 years) with 14 treated sites are included in this pilot study. Patients had a minimum of one papillary deficiency in the esthetic zone. Prior to treatment photographs were either taken at a 1:1 ratio or converted to a 1:1 ratio using a commercially available program. A standardization photographic device was not used. After administration of a local anesthetic, a 23‐gauge needle was used to inject less than 0.2 mL of a commercially available and Food and Drug Administration‐approved gel of hyaluronic acid 2–3 mm apical to the coronal tip of the involved papillae. Patients were seen every three weeks and treatment was repeated up to three times. Patients were followed from 6 to 25 months after initial gel application. A computer program measured changes in pixels between initial and final treatments. A formula was derived to determine percentage change in the negative space between initial and final examinations. Results: Each site was individually evaluated. Three implant sites and one site adjacent to a tooth had 100% improvement between treatment examinations. Seven sites improved from 94 to 97%, three sites improved from 76 to 88%, and one site adjacent to an implant had 57% improvement. Conclusion: Results from this pilot study are encouraging and present evidence that small papillary deficiencies between implants and teeth can be enhanced by injection of a hyaluronic gel. Improvements were maintained for a range of 6 to 25 months.     

稳定型含氯消毒剂的稳定性研究

目的研究稳定型含氯消毒剂存放过程中的稳定性。方法在半开放与封闭条件下，对有效氯浓度介于60～15000mg／L的稳定型含氯消毒剂进行长达590d的保存实验，并对其主要指标与消毒性能进行监测。结果保存条件与有效氯浓度对稳定型含氯消毒剂的稳定性有明显影响，较高含量的有效氯浓度与封闭保存条件可获得较长的保存期；在保存过程中稳定性含氯消毒剂的消毒能力略降，主要与其有效氯的衰减有关。结论在封闭保存条件下，稳定型含氯消毒剂的保存期可长达1年，并保持较强的消毒能力，具有实际使用价值。     

丹皮酚对囊性纤维化跨膜电导调节因子氯离子通道的激活作用

目的:研究丹皮酚对依赖于3’,5’-环腺苷酸(cAMP)的囊性纤维化跨膜电导调节因子(CFTR)Cl-通道的激活作用。方法:利用Cl-通道细胞荧光测定模型进行测定丹皮酚对CFTR介导的I-内流速度。结果:丹皮酚对野生型和ΔF508突变型CFTR Cl-通道均具有激活作用,而对G551D突变型CFTR Cl-通道无激活作用。丹皮酚在发挥激活作用时具有快速、可逆的特点并依赖于腺苷环化酶激动剂Forskolin的存在。初步确定了丹皮酚通过直接与CFTR结合发挥作用。结论:研究提示CFTR可能是某些中药降压作用药靶之一。此外,本实验为传统中药的降压作用的分子药理学机制作了初步探讨。     

One-year chronic toxicity of madder color in F344 rats – Induction of preneoplastic/neoplastic lesions in the kidney and liver

To evaluate chronic toxicity of madder color (MC), a natural food colorant extracted from the roots of Rubia tinctorum L., F344 rats were fed diet containing 0%, 0.2%, 1.0% or 5.0% MC for 53 weeks. Hematological changes including anemia and serum biochemical alterations indicating hepatotoxicity were demonstrated at 5.0% in both sexes. Relative weights of the liver were significantly increased from 1.0% in both sexes, and those of the kidney were significantly increased from 1.0% in males and from 0.2% in females. Histopathologically, atypical renal tubule hyperplasias were increased at 1.0% or higher in both sexes in association with increase of cell proliferative activity in the tubules. A renal cell adenoma was observed in a male rat receiving 5.0% MC. In addition, glutathione S-transferase placental form-positive liver cell foci were significantly increased at 5.0% in both sexes. These results indicate that MC has chronic toxicity targeting kidney, liver and blood cells. Moreover, the results strongly suggest that MC may have the carcinogenic potential in the kidney and the liver.