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Over four semesters of a large introductory statistics course the authors found students were engaging in contract cheating on Chegg.com during multiple choice examinations. In this paper we describe our methodology for identifying, addressing and eventually eliminating cheating. We successfully identified 23 out of 25 students using a combination of unique academic and digital fingerprints, and identified students who used virtual private networks (VPNs) to protect their online identity. There were two forms of cheating - posting questions and waiting for responses from tutors, and looking for questions that had already been solved. We found that 165 questions from these examinations were posted by 10 different students, but that the most common form of cheating was searching for answers that had already been posted. This paper discusses these patterns of Chegg usage, the consequences of not catching cheating early on, and how students reacted to being caught. Also provided are R and Python code that readers may use to identify cheating students in their own courses.

Ethyl-linked anthocyanin-flavanol pigments are one of the most important condensation products formed during the red winemaking and ageing period. They have great contribution to the color characteristics and stability of aged red wines. In this study, the color characteristics and stability of ethyl-linked anthocyanin-flavanol pigments and their precursor anthocyanins were evaluated by combined spectrophotometry and 3D molecular simulations. In model wine solutions, the condensation reactions between three anthocyanins and (-)-epicatechin, mediated by acetaldehyde, were conducted to produce ethyl-linked anthocyanin-flavanol pigments. The color was assessed by the CIELab method, and the concentration changes were analyzed by HPLC-DAD. On the other hand, the stability of these pigmented compounds was also calculated by the three 3D molecular simulation methods, that is molecular mechanics, molecular dynamics, and quantum chemistry simulation. The results obtained from CIELab analysis indicated that the formation of ethyl-linked anthocyanin-flavanol pigments resulted in a decrease of L*, a*, b* and C* values, and conversely, a rising of h* value. The 3D molecular simulations revealed that the stability of anthocyanins was as follows: Mv-3-O-glu > Pn-3-O-glu > Cy-3-O-glu. The cis or trans ethyl-linked anthocyanin-flavanol pigments were much more stable than their precursor anthocyanins. Among the pigments, ethyl-linked malvidin-3-O-glucoside-flavanol was more stable than ethyl-linked cyanidin-3-O-glucoside-flavanol and ethyl-linked peonidin-3-O-glucoside-flavanol.

Overproduction of reactive oxygen species (ROS), metal ion accumulation, and tricarboxylic acid cycle collapse are crucial factors in mitochondria‐mediated cell death. However, the highly adaptive nature and damage‐repair capabilities of malignant tumors strongly limit the efficacy of treatments based on a single treatment mode. To address this challenge, a self‐reinforced bimetallic Mito‐Jammer is developed by incorporating doxorubicin (DOX) and calcium peroxide (CaO2) into hyaluronic acid (HA) ‐modified metal‐organic frameworks (MOF). After cellular, Mito‐Jammer dissociates into CaO2 and Cu2+ in the tumor microenvironment. The exposed CaO2 further yields hydrogen peroxide (H2O2) and Ca2+ in a weakly acidic environment to strengthen the Cu2+‐based Fenton‐like reaction. Furthermore, the combination of chemodynamic therapy and Ca2+ overload exacerbates ROS storms and mitochondrial damage, resulting in the downregulation of intracellular adenosine triphosphate (ATP) levels and blocking of Cu‐ATPase to sensitize cuproptosis. This multilevel interaction strategy also activates robust immunogenic cell death and suppresses tumor metastasis simultaneously. This study presents a multivariate model for revolutionizing mitochondria damage, relying on the continuous retention of bimetallic ions to boost cuproptosis/immunotherapy in cancer. [ABSTRACT FROM AUTHOR]

Background: Breast cancer ranks first among malignant tumors, of which triple-negative breast cancer (TNBC) is characterized by its highly invasive behavior and the worst prognosis. Timely diagnosis and precise treatment of TNBC are substantially challenging. Abnormal tumor vessels play a crucial role in TNBC progression and treatment. Nitric oxide (NO) regulates angiogenesis and maintains vascular homeostasis, while effective NO delivery can normalize the tumor vasculature. Accordingly, we have proposed here a tumor vascular microenvironment remodeling strategy based on NO-induced vessel normalization and extracellular matrix collagen degradation with multimodality imaging-guided nanoparticles against TNBC called DNMF/PLGA. Results: Nanoparticles were synthesized using a chemotherapeutic agent doxorubicin (DOX), a NO donor L-arginine (L-Arg), ultrasmall spinel ferrites (MnFe2O4), and a poly (lactic-co-glycolic acid) (PLGA) shell. Nanoparticle distribution in the tumor was accurately monitored in real-time through highly enhanced magnetic resonance imaging and photoacoustic imaging. Near-infrared irradiation of tumor cells revealed that MnFe2O4 catalyzes the production of a large amount of reactive oxygen species (ROS) from H2O2, resulting in a cascade catalysis of L-Arg to trigger NO production in the presence of ROS. In addition, DOX activates niacinamide adenine dinucleotide phosphate oxidase to generate and supply H2O2. The generated NO improves the vascular endothelial cell integrity and pericellular contractility to promote vessel normalization and induces the activation of endogenous matrix metalloproteinases (mainly MMP-1 and MMP-2) so as to promote extravascular collagen degradation, thereby providing an auxiliary mechanism for efficient nanoparticle delivery and DOX penetration. Moreover, the chemotherapeutic effect of DOX and the photothermal effect of MnFe2O4 served as a chemo-hyperthermia synergistic therapy against TNBC. Conclusion: The two therapeutic mechanisms, along with an auxiliary mechanism, were perfectly combined to enhance the therapeutic effects. Briefly, multimodality image-guided nanoparticles provide a reliable strategy for the potential application in the fight against TNBC. [ABSTRACT FROM AUTHOR]

Background: Pectus excavatum, the most common chest wall deformity, is frequently treated with Nuss procedure. Here we will describe non-invasive procedure and analyze the variables associated vacuum bell therapy for patients with pectus excavatum. Methods: Retrospective case–control study in a single center between July 2018 and February 2022, including patients with pectus excavatum treated with vacuum bell. Follow-up was continued to September 2022. The Haller index and Correction index was calculated before and after treatment to analysis the effectiveness of vacuum bell therapy. Results: There were 98 patients enrolled in the treatment group, with 72 available for analysis, and the follow-up period ranged from 1.1 to 4.4 years (mean 3.3 years). When analyzing with the Haller Index, 18 patients (25.0%) showed excellent correction, 13 patients (18.1%) achieved good correction, and 4 patients (5.6%) had fair correction. The remaining patients had a poor outcome. Characteristics predicting a non-poor prognosis included initial age ≤ 11 years (OR = 3.94, p = 0.013) and patients with use over 24 consecutive months (OR = 3.95, p = 0.013). A total of 9 patients (12.5%) achieved a CI reduction below 10. Patients who started vacuum bell therapy at age > 11 had significantly less change compared to those who started at age ≤ 11 (P < 0.05). Complications included chest pain (5.6%), swollen skin (6.9%), chest tightness (1.4%) and erythema (15.3%). Conclusions: A certain percentage of patients with pectus excavatum can achieve excellent correction when treated with pectus excavatum therapy. Variables predicting better outcome including initial age ≤ 11 years both in HI and CI and vacuum bell use over 24 consecutive months in HI. In summary, pectus excavatum is an emerging non-invasive therapy for pectus excavatum and will be widely performed in a certain group of patients. [ABSTRACT FROM AUTHOR]

Over four semesters of a large introductory statistics course the authors found students were engaging in contract cheating on Chegg.com during multiple choice examinations. In this paper we describe our methodology for identifying, addressing and eventually eliminating cheating. We successfully identified 23 out of 25 students using a combination of unique academic and digital fingerprints, and identified students who used virtual private networks (VPNs) to protect their online identity. There were two forms of cheating – posting questions and waiting for responses from tutors, and looking for questions that had already been solved. We found that 165 questions from these examinations were posted by 10 different students, but that the most common form of cheating was searching for answers that had already been posted. This paper discusses these patterns of Chegg usage, the consequences of not catching cheating early on, and how students reacted to being caught. Also provided are R and Python code that readers may use to identify cheating students in their own courses. [ABSTRACT FROM AUTHOR]

The incorporation of insulating polymers into conjugated polymers has been widely explored as a strategy to improve mechanical properties of flexible organic electronics. However, phase separation due to the immiscibility of these polymers has limited their effectiveness. In this study, we report the discovery of multiple non‐covalent interactions that enhances the miscibility between insulating and conjugated polymers, resulting in improved mechanical properties. Specifically, we have added polyvinyl chloride (PVC) into the conjugated polymer PM6 and observed a significant increase in solution viscosity, indicative of favorable miscibility between these two polymers. This phenomenon has been rarely observed in other insulating/conjugated polymer composites. Thin films of PM6/PVC exhibit a much‐improved crack‐onset strain of 19.35 %, compared to 10.12 % for pristine PM6 films. Analysis reveal that a "cyclohexyl‐like" structure formed through dipole‐dipole interactions and hydrogen bonding between PVC and PM6 acted as a cross‐linking site in the thin films, leading to improved mechanical properties. Moreover, PM6/PVC blend films have demonstrated excellent thermal and bending stability when applied as an electron donor in organic solar cells. These findings provide new insights into non‐covalent interactions that can be utilized to enhance the properties of conjugated polymers and may have potential applications in flexible organic electronics. [ABSTRACT FROM AUTHOR]

Background: Evidence of osimertinib as neoadjuvant therapy for resectable non-small cell lung cancer (NSCLC) are currently lacking. This case series study aimed to assess the safety and feasibility of neoadjuvant osimertinib therapy followed by surgery for resectable NSCLC. Materials and methods: Patients with resectable NSCLC with epidermal growth factor receptor (EGFR) mutation who received osimertinib as neoadjuvant therapy followed by surgery at our center were included. Demographic features, radiologic and pathological assessment of response, surgery-related details and complications, toxicity profiles, and prognostic outcomes were extracted. Results: A total of 13 patients were included in this study. The median age at the time of surgical resection was 57 years (interquartile range: 52–64 years), and eight (61.5%) patients were female. The objective response rate (ORR) was 69.2% (9/13), and the complete resection rate was 100%. The rates of pathologic downstaging and lymph node downstaging were 100% (13/13) and 66.7% (6/9), respectively. There were no perioperative deaths and only three (23.1%) patients had postoperative complications. Seven (53.8%) and 13 (100%) patients experienced grade 1 treatment-related adverse reactions and laboratory abnormalities, respectively. No patients experienced drug withdrawal or surgical delays due to the adverse events. No patients showed grade 2 or worse toxicity profiles. One patient was lost to follow-up. The other 12 patients were alive and free of disease recurrence with a median follow-up time of 9.5 months. Conclusion: Neoadjuvant osimertinib therapy seemed to be safe and feasible for resectable EGFR-mutated NSCLC. Future large prospective studies are warranted to confirm whether osimertinib as neoadjuvant therapy outperforms standard tyrosine kinase inhibitors (TKIs) or chemotherapy for resectable EGFR-mutated NSCLC. [ABSTRACT FROM AUTHOR]

Flexible chiral honeycomb cores generally exhibit nonlinear elastic properties in response to large geometric deformation, which are suited for the design of morphing aerospace structures. However, owing to their complex structure, it is standard to replace the actual core structure with a homogenized core material presenting reasonably equivalent elastic properties in an effort to increase the speed and efficiency of analyzing the mechanical properties of chiral honeycomb sandwich structures. As such, a convenient and efficient method is required to evaluate the effective elastic properties of flexible chiral honeycomb cores under conditions of large deformation. The present work develops an analytical expression for the effective elastic modulus based on a deformable cantilever beam under large deformation. Firstly, Euler-Bernoulli beam theory and micropolar theory are used to analyze the deformation characteristics of chiral honeycombs, and to calculate the effective elastic modulus under small deformation. On that basis, the expression for the effective elastic modulus is improved by including the stretching deformation of the chiral honeycomb structure for a unit cell under conditions of large deformation. The effective elastic moduli calculated by the respective analytical expressions are compared with the results of finite element analysis. The results indicate that the analytical expression obtained under consideration of the geometric nonlinearity is more suitable than the linear expressions for flexible chiral honeycomb cores under conditions of high strain and low elastic modulus. [ABSTRACT FROM AUTHOR]

Sustainable conversion of wastes into eco-friendly wearable energy storage materials is of uppermost priority when facing the rapid development of human society. Although some attempts have successfully developed wastes into activated carbon electrodes, the high energy consumption of the production process and the powder form greatly restrict their application in eco-friendly wearable supercapacitors. Here, industrial waste-flax noil was conversed into fiber-shaped supercapacitors (FSSCs) via wet spinning and in situ deposition of polypyrrole (PPy). The regenerated cellulose fibers (RCFs) collected from the ethyl alcohol coagulation bath possessed excellent tensile behaviors and multi-groove surfaces, encouraging the subsequent textile processing and ions activities. After PPy deposition, the obtained fiber electrodes yielded high specific capacitance (510.7 F g-1 at 0.5 A g-1) and excellent coulombic efficiency (99.3% at 10 A g-1). More importantly, the assembled FSSCs delivered remarkable electrochemical performances and could power the LED. The green strategy proposed in this work provides a new consideration for converting wastes into practical eco-friendly wearable devices. [Display omitted] • Flax noil was successfully converted into eco-friendly fiber supercapacitors. • ETf@PPy12 electrodes possessed high specific capacitance and coulombic efficiency. • The assembled flexible supercapacitor showed superior electrochemical performance. • The devices in series could power the LED. [ABSTRACT FROM AUTHOR]

Two kinds of small molecular dyads (SMDs) based on trithiophene-benzodithiophene-rhodanine (DR3TBDT) main backbone and PBI termini, named SMD2-C6 and SMD2-C12, were designed with different lengths of alkyl linkers (C 6 H 12 and C 12 H 24). The length effect of alkyl linkers on the photovoltaic performance of the two SMDs have been systematically studied. The results show that the length of alkyl linkers can simutaneously tune the energy levels and phase separation in molecular dyad thin films. As a result, a power conversion efficiency of 1.33% was obtained for SMD2-C12 based single-component organic solar cells (SCOSCs), showing higher open-circuit voltage, short-circuit current density, and fill factor than those of SMD2-C6 based devices. Our findings provide a strategy for designing new SMDs and reveal the importance of alkyl linkers' length on the morphology of SMDs toward improved SCOSC performance. Small molecular dyads based on DR3TBDT backbone and PBI end groups with varying alkyl linker lengths have been developed for application in single-component organic solar cells. [Display omitted] • Two molecular dyads based on a donor backbone and perylene bisimides end groups were developed. • Different alkyl linkers as C 6 H 12 and C 12 H 24 were introduced. • Longer alkyl linkers were found to improve the nanophase separation and provided higher efficiency in single-component organic solar cells. [ABSTRACT FROM AUTHOR]