Monitoring the dynamic changes in aroma during the whole processing of Qingzhuan tea at an industrial scale: From fresh leaves to finished tea.

Aroma is one of the most outstanding quality characteristics of Qingzhuan tea (QZT), but its formation is still unclear. Thus, the volatile organic compounds (VOCs) during the whole processing of QZT were investigated by headspace solid-phase microextraction/gas chromatography-mass spectrometry. Based on 144 identified VOCs, the results showed that de-enzyming, sun-drying, and piling fermentation were the key processes of QZT aroma formation.

Dynamic Analysis of Physicochemical Properties and Polysaccharide Composition during the Pile-Fermentation of Post-Fermented Tea.

Ultra-high performance liquid chromatography-quadrupole-time of flight tandem mass spectrometry (UHPLC-Q-TOF-MS/MS) was used to study the diversity of tea polysaccharides and the dynamic changes in the physicochemical indexes of tea samples. FT-IR spectra and the free radical scavenging ability of tea polysaccharides, during pile-fermentation of post-fermented tea, were analyzed. The results showed that 23 saccharide co mponents in tea polysaccharides were identified: these belonged to 11 monosaccharides, 5 oligosaccharides, and 6 derivatives of monosaccharides and oligosaccharides.

Indoor Passive Visual Positioning by CNN-Based Pedestrian Detection.

Indoor positioning applications are developing at a rapid pace; active visual positioning is one method that is applicable to mobile platforms. Other methods include Wi-Fi, CSI, and PDR approaches; however, their positioning accuracy usually cannot achieve the positioning performance of the active visual method. Active visual users, however, must take a photo to obtain location information, raising confidentiality and privacy issues.

Indoor Visual Positioning Aided by CNN-Based Image Retrieval: Training-Free, 3D Modeling-Free.

Indoor localization is one of the fundamentals of location-based services (LBS) such as seamless indoor and outdoor navigation, location-based precision marketing, spatial cognition of robotics, etc. Visual features take up a dominant part of the information that helps human and robotics understand the environment, and many visual localization systems have been proposed. However, the problem of indoor visual localization has not been well settled due to the tough trade-off of accuracy and cost.

An Indoor Positioning System Based on Static Objects in Large Indoor Scenes by Using Smartphone Cameras.

The demand for location-based services (LBS) in large indoor spaces, such as airports, shopping malls, museums and libraries, has been increasing in recent years. However, there is still no fully applicable solution for indoor positioning and navigation like Global Navigation Satellite System (GNSS) solutions in outdoor environments. Positioning in indoor scenes by using smartphone cameras has its own advantages: no additional needed infrastructure, low cost and a large potential market due to the popularity of smartphones, etc.

Visual Positioning Indoors: Human Eyes vs. Smartphone Cameras.

Artificial Intelligence (AI) technologies and their related applications are now developing at a rapid pace. Indoor positioning will be one of the core technologies that enable AI applications because people spend 80% of their time indoors. Humans can locate themselves related to a visually well-defined object, e.

Arylurea Derivatives: A Class of Potential Cancer Targeting Agents.

Arylurea derivatives, an important class of small molecules, have received considerable attention in recent years due to their wide range of biological applications. Various molecular targeted agents with arylurea scaffold as potential enzyme/receptor inhibitors were constructed with the successful development of sorafenib and regorafenib. This review focuses on those arylureas possessing anti-cancer activities from 2010 to date.

An auto-adaptive background subtraction method for Raman spectra.

Background subtraction is a crucial step in the preprocessing of Raman spectrum. Usually, parameter manipulating of the background subtraction method is necessary for the efficient removal of the background, which makes the quality of the spectrum empirically dependent. In order to avoid artificial bias, we proposed an auto-adaptive background subtraction method without parameter adjustment.

Design, synthesis, and biological evaluation of novel quinazolinyl-diaryl urea derivatives as potential anticancer agents.

Through a structure-based molecular hybridization approach, a series of novel quinazolinyl-diaryl urea derivatives were designed, synthesized, and screened for their in vitro antiproliferative activities against three cancer cell lines (HepG2, MGC-803, and A549). Six compounds (7 g, 7 m, 7 o, 8 e, 8 g, and 8 m) showed stronger activity against a certain cell line compared with the positive reference drugs sorafenib and gefitinib. Among the six compounds, 8 g exhibited the strongest activity.

Synthesis, Fluorescence Properties, and Antiproliferative Potential of Several 3-Oxo-3H-benzo[f]chromene-2-carboxylic Acid Derivatives.

In this study, two series of 3-oxo-3H-benzo[f]chromene-2-carboxylic acid derivatives (compounds 5a-i and 6a-g) were synthesized. Their in vitro proliferation inhibitory activities against the A549 and NCI-H460 human non-small cell lung cancer (NSCLC) cell lines were evaluated. Their photophysical properties were measured.