The design of smart surfaces with switchable adhesive properties in a wet environment has remained a challenge in adhesion science and materials engineering. Despite intense demands in various ...industrial applications and exciting progress in mimicking the remarkable wet adhesion through the delicate control of catechol chemistry, polyelectrolyte complex, and supramolecular architectures, the full recapitulation of nature's dynamic function is limited. Here, we show a facile approach to synthesize bioinspired adhesive, which entails the reversible, tunable, and fast regulation of the wet adhesion on diverse surfaces. The smart wet adhesive takes advantage of the host-guest molecular interaction and the adhesive nature of catechol chemistry, as well as the responsive polymer, allowing for screening and activation of the interfacial interaction simply by a local temperature trigger in an on-demand manner. Our work opens up an avenue for the rational design of bioinspired adhesives with performances even beyond nature.
Nowadays, adversarial examples of images which are generated by adding special perturbations on their hosts make great impact on many deep neural network (DNN)‐based computer vision tasks and bring ...security risks. With the deep insight into this field, researchers realize that many simple image processing methods can easily reduce the attack success rate. Therefore, studies on robust adversarial examples that are able to defend destruction become the emphasis. However, most existing methods focus more on the distortion in user transmitting procedures and physical deformation such as JPEG compression and brightness. Given that scale transformation is one of the commonest measures in data transformation and enhancement, a two‐step algorithm is proposed to eliminate the effect caused by resizing during the model inferring process. The first step is to select pixels that can affect the classification result through a DNN. As a binary classification task, the network predicts whether the pixel deserves to be modified or not. The second one is to strategically compute the amplitude of noise and add it to the host image. Experiments verify that this method resists the scale transformation and guarantees the invisibility of humans as well.
A new protocol for the construction of a crucial bicyclic lactone of prostaglandins using a stereocontrolled organocatalytic Baeyer–Villiger (B‐V) oxidation was developed. The key B‐V oxidation of a ...racemic cyclobutanone derivative with aqueous hydrogen peroxide has enabled an early‐stage construction of a bicyclic lactone skeleton in high enantiomeric excess (up to 95 %). The generated bicyclic lactone is fully primed with two desired stereocenters and enabled the synthesis of the entire family of prostaglandins according to Corey′s route. Furthermore, the reactivity and enantioselectivity of B‐V oxidation of racemic bicyclic cyclobutanones were evaluated and 90–99 % ee was obtained, representing one of the most efficient routes to chiral lactones. This study further facilitates the synthesis of prostaglandins and chiral lactone‐containing natural products to promote drug discovery.
The core of the matter: A crucial bicyclic lactone containing two stereocenters was accessed through a new stereocontrolled organocatalytic Baeyer–Villiger oxidation of racemic cyclobutanone with aqueous hydrogen peroxide. This key intermediate enabled the assembly of the prostaglandin family of natural products.
Endometriosis is diagnosed by laparoscopic surgery. The availability of biomarkers can help understand the pathophysiology and aid in the diagnosis of the condition. In this context, this review ...aimed to examine levels of expression of brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) are increased amongst patients with endometriosis and if they can serve as a potential biomarker. PubMed, CENTRAL, Scopus, Web of Science, and Embase databases were searched for studies comparing BDNF or NGF levels amongst endometriosis patients and controls. Data were pooled for serum and tissue levels of BDNF and NGF. Ten fulfilled the inclusion criteria. On comparing BDNF levels, it was noted that endometrial tissue had significantly higher expression of BDNF levels as compared to controls (SMD: 1.73 95% CI: 0.64, 2.82 I2 = 89%). Similarly, the meta-analysis found significantly higher serum levels of BDNF in endometriosis patients as compared to controls (SMD: 1.66 95% CI: 0.73, 2.59 I2 = 95%). Pooled analysis showed significantly increased levels of NGF in endometrial tissue as compared to controls (SMD: 4.15 95% CI: 0.11, 8.18 I2 = 98%) but with unstable results on sensitivity analysis. Only one study showed higher levels of NGF in serum amongst endometriosis patients. Limited data shows higher expression of BDNF in endometrial lesions and increased serum levels of BDNF in endometriosis patients. Similar results were noted for NGF but with very scarce data. Further research is needed to establish BDNF and NGF as suitable biomarkers for the disease.
The Internet of Medical Things (IoMT) is a brand new technology of combining medical devices and other wireless devices to access to the healthcare management systems. This article has sought the ...possibilities of aiding the current Corona Virus Disease 2019 (COVID-19) pandemic by implementing machine learning algorithms while offering emotional treatment suggestion to the doctors and patients. The cognitive model with respect to IoMT is best suited to this pandemic as every person is to be connected and monitored through a cognitive network. However, this COVID-19 pandemic still remain some challenges about emotional solicitude for infants and young children, elderly, and mentally ill persons during pandemic. Confronting these challenges, this article proposes an emotion-aware and intelligent IoMT system, which contains information sharing, information supervision, patients tracking, data gathering and analysis, healthcare, etc. Intelligent IoMT devices are connected to collect multimodal data of patients in a surveillance environments. The latest data and inputs from official websites and reports are tested for further investigation and analysis of the emotion analysis. The proposed novel IoMT platform enables remote health monitoring and decision-making about the emotion, therefore greatly contribute convenient and continuous emotion-aware healthcare services during COVID-19 pandemic. Experimental results on some emotion data indicate that the proposed framework achieves significant advantage when compared with the some mainstream models. The proposed cognition-based dynamic technology is an effective solution way for accommodating a big number of devices and this COVID-19 pandemic application. The controversy and future development trend are also discussed.
Abstract
Background
Patients with chronic obstructive pulmonary disease (COPD) commonly have coexisting comorbidities that contribute to higher exacerbation frequency, poorer health status, and ...increased all-cause mortality; however, there are only a few studies available on the sex discrepancy in the comorbidity distribution and outcomes among COPD patients, and there is limited information about the discrepancy in all-cause mortality between men and women.
Methods
Based on data from the U.S. National Health and Nutrition Examination Survey conducted between 2007 and 2012, we compared participants aged 40–79 years with spirometry-defined COPD to compare the prevalence of comorbidities between men and women. The survival of the subjects was documented, and the sex discrepancy was determined using Kaplan–Meier analysis. Comorbidities and all-cause mortality were analyzed by using a Cox proportional hazards model to determine their strength of association in different sex groups.
Results
Compared to men, women had a significantly higher prevalence of asthma (OR 1.93, 95% CI 1.46 to 2.57, p < 0.001) and arthritis (OR 1.77, 95% CI 1.39 to 2.24, p < 0.001). Women had a significantly lower prevalence of coronary heart disease (OR 0.48, 95% CI 0.27 to 0.87, p = 0.015) and gout (OR 0.42, 95% CI 0.25 to 0.67, p = 0.001). Kaplan–Meier analysis revealed that compared with that of the female group, the survival rate of the male group was significantly lower (p < 0.001). Among men, the presence of anemia (HR 2.38, 95% CI 1.52–3.73, p < 0.001), gout (HR 1.55, 95% CI 1.04–2.30, p = 0.029) and congestive heart failure comorbidities (HR 1.85, 95% CI 1.12–3.04 p = 0.016) was associated with a higher risk of mortality; among women, the presence of anemia (HR 2.21, 95% CI 1.17–4.20, p = 0.015) and stroke (HR 2.04, 95% CI 1.07–3.88, p = 0.031) comorbidities was associated with a higher risk of mortality after adjusting for age, race/Hispanic status, BMI, smoking status, FEV1% predicted and prevalent comorbidities.
Conclusions
COPD-related comorbidities and all-cause mortality were discrepant between men and women, and men had poorer survival than women in the nationally representative data that were analyzed.
Food and feed are frequently co-contaminated with aflatoxin B1 (AFB1) and zearalenone (ZEN). This study investigated the effects of ZEN on the AFB1–induced liver and mammary gland toxicity in ...pregnant and lactating rats. AFB1 and ZEN co-exposure inhibited the growth of rats and caused oxidative stress and inflammatory responses in the liver and mammary gland. Compared with the AFB1-only group, damage was aggravated in the AFB1 + 10 mg/kg ZEN group, and the AFB1 + 1 mg/kg ZEN group showed a reduction in some metrics. The metabolomic results of the mammary gland showed that metabolite changes were mainly in lipid, amino acid, and glucose metabolism. Compared with the AFB1 + 0 mg/kg ZEN group, the AFB1 + 1 mg/kg ZEN group had the most metabolite changes. Moreover, AFB1 and ZEN co-exposure reduced the levels of sex hormones and RNA m6A methylation in the mammary gland. We speculate that ZEN affects the toxicity of AFB1 to the liver and mammary gland by interfering with the function of sex hormones, regulating cell proliferation and metabolic processes.
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•Aflatoxin B1 and zearalenone impair rat growth during pregnancy and lactation.•Zearalenone enhances the toxicity of aflatoxin B1 in liver and mammary gland.•The altered metabolites are mostly lipids, amino acids, and carbohydrates.•Aflatoxin B1 and zearalenone increase the risk of mastitis and breast cancer.
The asymmetric synthesis of (−)-chloramphenicol, (−)-azidamphenicol, and (+)-thiamphenicol and its (+)-3-floride, (+)-florfenicol, is reported. This approach toward the amphenicol antibiotic family ...features two key steps: (1) a cinchona alkaloid derived urea-catalyzed aldol reaction allows highly enantioselective access to oxazolidinone gem-diesters and (2) a continuous flow diastereoselective decarboxylation of thermally stable oxazolidinone gem-diesters to form the desired trans-oxazolidinone monoesters with two adjacent stereocenters that provide the desired privileged scaffolds of syn-vicinal amino alcohols in the amphenicol family.
A nitrogen-doped carbon material with developed porous structure was prepared by the simple single-step pyrolysis of sodium alginate and 1, 6-hexanediamine. Nitrogen-doped carbon catalysts were ...optimized and characterized, and their catalytic activities were investigated using the self-oxidative coupling of amine as model reaction. N2 adsorption-desorption exhibited that the introduction of 1, 6-hexanediamine could observably increase the specific surface area and pore volume of the carbon material. X-ray photoelectron spectroscopy confirmed N was incorporated successfully into the carbon. Benefiting from these, nitrogen-doped carbon material exhibited high catalytic performance for the oxidation of amines to imines under solvent-free, air atmospheric conditions. And the nitrogen-doped carbon possessed good reusability and applicability. Meanwhile, the nitrogen-doped carbon material was available, low cost and environment-friendly owing to the use of cheap, renewable natural starting materials and simple synthetic procedure.
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•Nitrogen-doped carbon material with developed porous structure was prepared by the simple single-step pyrolysis of SA and TAAH.•1,6-hexanediamine could regulate the structure and catalytic performance of nitrogen-doped carbon material.•Nitrogen-doped carbon material exhibited excellent catalytic activity for the oxidation of amines to imines under solvent-free, air atmospheric conditions.
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