Predicting Perceived Brand Personality with Social Media

Brand personality has been shown to affect a variety of user behaviors such as individual preferences and social interactions. Despite intensive research efforts in human personality assessment, little is known about brand personality and its relationship with social media. Leveraging the theory in marketing, we analyze how brand personality associates with its contributing factors embodied in social media. Based on the analysis of over 10K survey responses and a large corpus of social media data from 219 brands, we quantify the relative importance of factors driving brand personality. The brand personality model developed with social media data achieves predicted R2 values as high as 0.67. We conclude by illustrating how modeling brand personality can help users find brands suiting their personal characteristics and help companies manage brand perceptions

Hydrogen bond donor functionalized poly(ionic liquid)s for efficient synergistic conversion of CO2 to cyclic carbonates

The development of metal-free, high effective and recyclable catalysts plays a pivotal role in transforming CO2 into high value-added products such as cyclic carbonates. In this paper, we introduced the hydrogen bond donor (HBD) groups into poly(ionic liquid)s via free radical polymerization, which successfully combined the HBD and ionic liquids (ILs) into one heterogeneous catalyst. The HBD could synergistically activate epoxides with hydroxyl functionalized ionic liquids and efficiently catalyze the cycloaddition of CO2 into cyclic carbonates. The yield of propylene carbonate (PC) reached 94% (at 105 degrees C, 2 MPa CO2, 3 h), which far exceeded poly(ionic liquid)s without HBDs functionalization (PC yield 72%), and even approached bulk ionic liquids (PC yield 95%). Moreover, HBD-functionalized poly(ionic liquid)s (HPILs) exhibited excellent recyclability after five runs and afforded wide substrate scope. According to the experimental results, H-1 NMR spectra and density functional theory (DFT) calculations showed 2-hydroxyethyl methacrylate (HEMA) and the hydroxyl of ILs would form strong H-bonds with epoxides contributing to the ring-opening process of epoxides, and a possible HBD and nucleophilic anion synergistically catalytic mechanism was proposed. The method herein paved a brand new way for green technology and utilization of poly(ionic liquid)s

Efficient synthesis of bio-derived polycarbonates from dimethyl carbonate and isosorbide: regulatingexo-OH andendo-OH reactivity by ionic liquids

It is an immense challenge to design catalysts for synthesizing high molecular weight polycarbonates using CO2, CO2-based compounds, or biorenewable chemicals as building blocks. To this end, an eco-compatible approach to synthesizing polycarbonates from biorenewable isosorbide and CO2-derived dimethyl carbonate (DMC) has been exploited: the regulation of poly(isosorbide carbonate) molecular weight can be achieved by modifying the cation structure of ionic liquid (IL) catalysts. The hydrogen bond donating and accepting ability of ILs can be altered by adjusting the cation structure, which successfully leads to the tunability of the intrinsic imbalance reactivity ofexo-OH andendo-OH in isosorbide. Moreover, these ILs exclusively activate the carbonyl carbon of DMC for accelerating the polymerization reaction. These features are appealing superiorities of ILs as compared to catalysts involving metallic elements. The [Emim]Br catalyst remarkably decreased the imbalanced reactivity of -OH groups of isosorbide, and exhibited the highest catalytic activity. With the presence of [Emim]Br, the poly(isosorbide carbonate) (PIC) weight-average molecular weight and glass transition temperature attained were 52 100 g mol(-1)and 156 degrees C, respectively. Additionally, according to experimental results, DFT calculations, andin situ(1)H NMR analysis, a possible polymerization mechanism indicates that bromine-derived ILs participate in nucleophilic-electrophilic dual-activation in catalyzing PIC synthesis. Our work offers a direction to design catalysts for synthesizing PICs with higher molecular weights through an eco-compatible route

The effect of antibiotic prophylaxis on the incidence of surgical site infection after laparoscopic appendectomy for chronic appendicitis

Background: The guidelinesthat specify whether antibiotic prophylaxis should be administered before laparoscopic clean-contaminated wound to prevent postoperative surgical site infection (SSI) need to be improved. Studies have shown that elective laparoscopic cholecystectomy with clean-contaminated wound does not require antibiotic prophylaxis. However, there are no studies on the effect of antibiotic prophylaxis on SSI after laparoscopic appendectomy for chronic appendicitis (LCA), which is a clean-contaminated wound. Methods: We conducted a single-center, double-blind, randomized controlled clinical trial. A total of 106 effective patients were randomly divided into the antibiotic group and saline group. Cefuroxime or clindamycin was administered intravenously in the antibiotic group (n = 52). Saline (0.9%) was administered intravenously in the saline group (n = 54). Interventions were administered as a single dose 30 min before surgery. Results: Among the 106 effective patients (median age, 37 years old [IQR, 25–45]; females, 77 [72.6%]), there were 6 cases (5.70%) of SSI: 3 cases (5.56%) in the saline group and 3 cases (5.70%) in the antibiotic group (OR = 1.00, [95% CI (0.20–5.4)], P = 0.96). There were no significant differences in the clinical outcomes of anal exhaust time, postoperative complications, and the symptom of primary abdominal pain between the two groups. Conclusion: For patients with chronic appendicitis undergoing laparoscopic appendectomy, preoperative intravenous antibiotic prophylaxis did not reduce the risk of SSI within 30 days of the surgery compared to the saline group. Trial registration: Registration number of China Clinical Trials Registration Center: ChiCTR2100048336