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Abstract The surfactant-polymer-based (S/P) fracturing fluid combines the advantages of the surfactant-based and polymer-based fracturing fluids. In this study, the synergistic tackifying of cationic surfactants and carboxymethyl hydroxyethyl cellulose and the potential application in hydraulic fracturing fluid was investigated. Firstly, cetyltrimethylammonium chloride (CTAC) and salicylic acid (SA) with a weight ratio of 4:1 were optimized as the main agent of the small molecule surfactant gel, which was then mixed with carboxymethyl 2-hydroxyethyl ether cellulose (CMHEC) and salicylic acid (SA) to obtain the S/P gel. The proppant suspension performance, gel-breaking properties, salt-resistance and thermal stability of the optimized S/P were evaluated to confirm their potential application in the hydraulic fracturing fluid. These results showed that the performance of the S/P fracturing fluid system was much better than the performance of the surfactant fracturing fluid and also the performance of polymer fracturing fluid.

ABSTRACT Objective: To assess the effect of Chahuang ointment, a Chinese herbal ointment, on the prevention of phlebitis in patients with peripherally inserted central catheters. Method: This was a multicenter randomized controlled trial, with 171 eligible patients randomly assigned into one of three groups: the Chahuang ointment group, the Mucopolysaccharide Polysulfate cream group, and the control group. The degrees of vein injuries at 72 hours after peripherally inserted central catheter insertion were the primary outcome. Secondary outcomes were the vascular wall thickness, tissue edema and microthrombus evaluated by Color Doppler Flow Imaging, the vascular endothelial growth factor, and endothelin-1 (ET-1) expression in vivo. Results: Compared with the control group, the Chahuang ointment group showed significantly lower incidence of postoperative phlebitis, tissue edema, and microthrombus at 72 hours after peripherally inserted central catheter insertion (all P0.05). Conclusion: Chahuang ointment was shown to provide effective prevention and protection against phlebitis after peripherally inserted central catheter insertion.

ABSTRACT We evaluated the difference between rumen bacteria in Tan sheep fed either by grazing or in a feedlot. The aim was to provide a theoretical basis for ruminant nutrition and meat quality based on rumen fermentation. Twenty-four three-month-old Tan sheep were randomly and equally divided into two groups, the grazing group and ration group. Five sheep of each group were selected for slaughter at six months of age. Ruminal contents were collected and assessed to identify rumen bacteria, based on 16S rDNA sequencing analysis. A total of 17 phyla were identified, among which Bacteroidetes, Firmicutes, and Proteobacteria were dominant in both groups. The abundance of Firmicutes was higher in grazing group than in the ration group, while that of Proteobacteria was opposite. Besides the dominant phyla differences, the abundance of Fibrobacteres, Tenericutes, Elusimicrobia, and Cyanobacteria was significantly higher in the grazing group compared with the ration group. At genus level, a total of 174 genera were identified. The abundance of Rikenellaceae_RC9_gut_group, Dialister, Lachnospiraceae_NA, Catonella, Ruminococcaceae_UCG-014, Lachnospiraceae_NK3A20_group, and Fibrobacter in the grazing group was higher than in the ration group. However, the abundance of Succinivibrionaceae_NA was lower in the grazing group, and Succinivibrionaceae_UCG-001 showed a decreasing trend in the grazing group. The two feeding methods may influence the rumen bacterial composition, including the abundance of dominant bacteria, as well as the cellulolytic- and carbohydrate-degrading bacteria in the rumen of Tan sheep.

Abstract In this paper, a novel zwitterionic copolymer AM/SSS/THDAB clay hydration dispersion inhibitor was synthesized by copolymerization of tris hydroxyethyl diallyl ammonium bromide (THDAB), sodium p-styrene sulfonate (SSS) and acrylamide (AM) initiated in an aqueous solution. The copolymer was characterized by FT-IR, GPC, TGA-DSC and SEM. Results demonstrated that molecular weight of AM/SSS/THDAB was 43674 g/mol and its temperature resistance ability was up to 225 °C. Evaluation experiments showed that AM/SSS/THDAB has an excellent clay hydration inhibitive performance. Methods including particle size analysis and SEM were utilized to study its dispersion inhibition mechanism by using sodium montmorillonite (Na-MMT). Results indicated that the micro-structure of Na-MMT has been successfully changed by AM/SSS/THDAB. In a word, the superior inhibition property makes the novel clay hydration dispersion inhibitor promised in water-based drilling fluids.

Objective:Evidence suggests that early-onset obsessive-compulsive disorder (OCD) is an etiologically distinct subtype of OCD. The objective of the present work was to search for neurocognitive endophenotypes of early-onset OCD based on assessments of attention, memory, and executive function in patients with the disorder and their unaffected siblings.Methods:We compared the performance of 40 adult patients with early-onset OCD, 40 of their unaffected siblings, and 40 unrelated healthy controls on a neuropsychological battery designed for this study. We searched for associations among test performance, demographic variables (age, sex and years of education) and clinical symptoms of early-onset OCD.Results:Patients performed significantly worse than healthy controls on the Tower of Hanoi, and the Stroop and Wisconsin tests, indicating impairments in planning, mental flexibility and inhibitory control. The performance of the unaffected first-degree siblings of patients with early-onset OCD on the Stroop and Wisconsin tests also differed from that of healthy controls. Symptom severity in early-onset OCD was strongly correlated with performance on the Tower of Hanoi.Conclusions:Our findings support the existence of specific executive function deficits in patients with early-onset OCD. Relatives presented an intermediate phenotype between patients and controls, suggesting that executive functions such as mental flexibility and response inhibition may be considered candidate endophenotypes of early-onset OCD.

ABSTRACT To demonstrate the role of gonadotropin-releasing hormone (GnRH) in yaks (Bos grunniens), we characterized the expression of gonadotropin-releasing hormone receptor (GnRHR) mRNA and protein. The level of GnRHR mRNA in the hypothalamus was higher than that in the pineal gland, pituitary gland, and ovary during estrus. Immunofluorescence analysis showed that GnRHR was expressed in the pinealocyte, synaptic ribbon, and synaptic spherules of the pineal gland and that melatonin interacts with GnRHR via nerve fibers. In the hypothalamus, GnRHR was expressed in the magnocellular neurons and parvocellular neurons. In the pituitary gland, GnRHR was expressed in acidophilic cells and basophilic cells. In the ovary, GnRHR was present in the ovarian follicle and Leydig cells. Gonadotropin-releasing hormone receptor is located in the pineal gland, hypothalamus, pituitary, and gonad during estrus of yaks and is mainly expressed in the hypothalamus and ovaries during the estrus period.