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Cracked carrots account for a large proportion of defective carrots, which are usually discarded or used as feed, resulting in resource waste and economic benefit loss. Cracked carrots can be used as raw materials for further processed carrot products after being trimmed. So, an auxiliary device was developed combining PLC (Programmable Logic Controller) and machine vision to achieve clamping and crack defect localization for intelligent trimming of crack defect. The carrot was orientated based on the area method, rotated by flexible jaws and a rotating cylinder to make the carrot head and tail aligned. The clamping device could non‐destructively clamp carrot in axial and radial direction with a force threshold of 10 and 22 N respectively, and rotate carrot to make the crack defect upwards. The results showed that the recognition accuracy of carrot head and tail orientation was 98%, the average deviation of carrot centroid clamping position was less than 9 mm at a speed of 300 mm/s, the rotational positioning time was less than 3 s and the number of adjustments were no more than 2 at a motor speed of 180 rpm, which could meet the subsequent trimming requirements. Practical applications: Trimming the cracked area of carrots can reduce bacterial growth and decay, which is beneficial for subsequent processing and reduces resource waste. This article designs a carrot auxiliary trimming device, which uses image processing technology to recognize the orientation of the head and tail of carrots and the cracked area, and uses automated equipment to achieve stable clamping of carrots and make the cracked area face the trimming tool. This study is beneficial for the refined management of agricultural products. [ABSTRACT FROM AUTHOR]

Forked carrots are often used as animal feed or discarded directly, which affects ​the economic returns of growers and leads to resource waste and environmental pollution. After trimming, forked carrots become easier to peel and can be further processed. However, the lack of relevant studies and equipment hinders the full use of forked carrots, and the identification of fork points and determination of the trimming path are the main challenges in trimming forked carrots with unique and diverse shapes. Therefore, an automatic carrot‐trimming path recognition solution based on contour analysis and machine learning was proposed in this study to address the above challenges. Specifically, a cascaded model and a parallel model consisting of Multilayer Perceptron (MLP) and Support Vector Machine (SVM) were constructed to identify fork points, and three trimming path determination methods based on fork points and carrot contours were proposed. The results demonstrated cascaded and parallel models achieved 100% and 92.7% recall rates, respectively, with accuracy rates of 90.4% and 100% and repetition rates of 97.1% and 96.4%. Among the trimming path determination methods, both the dynamic convex hull method and the static convex hull method achieved a convexity of 94.7%, surpassing 93.1% for the slope method. The static convex hull method exhibited the fastest speed in determining the trimming path, taking only 0.0032 s per carat. The parallel model and the static convex hull method could be effectively used for online determination of the trimming path for forked carrots. Practical applications: Trimming forked carrots enhances usability, reduces resource wastage, and mitigates environmental pollution. Leveraging contour‐based machine learning algorithms, we achieved precise fork point recognition with broad applicability. Using fork point and carrot contour data, we determined trimming paths that render carrots convex for mechanical peeling. This approach contributes to advancing sustainable agriculture by optimizing resource utilization. [ABSTRACT FROM AUTHOR]

A CuI/L‐proline‐catalyzed reaction of 2‐(2‐bromophenyl)‐4,5‐diaryl‐1H‐imidazole and potassium ethylxanthate unexpectedly gave bis(2‐(4,5‐diaryl‐1H‐imidazol‐2‐yl)phenyl)sulfane derivatives in high yields, rather than 2,3‐diphenyl‐5H‐benzo[e]imidazo[1,2‐c]thiazine‐5‐thione. This cascade procedure provided an efficient method to synthesize diphenylsulfanes using potassium ethylxanthate as a new type of sulfur source via the Csp2S bond Ullmann reaction twice. [ABSTRACT FROM AUTHOR]

A silver‐catalyzed protocol for [3+1+1] annulation of nitrones and isocyanoacetates is reported. The reaction is proposed to proceed through sequential [3+2] cycloaddition, ring‐opening, cyclization‐oxidation, and dealkylation, allowing access to a broad scope of valuable polysubstituted imidazoles in high yields. [ABSTRACT FROM AUTHOR]

The technique of backside thinning is used to obtain thinner freestanding GaN membrane. This technique is helpful for producing stronger reflectance peaks and to reduce the reflectance spectra quantity and reflectance interference in the visible light range. Ion beam etching (IBE) was used to fabricate a GaN membrane grating, and the size of the tapered angle of which has an important affect on the reflectance spectra modes. Therefore, we presented a GaN membrane grating model with tapered angle which is built based on a GaN-on-silicon wafer structure. The influence of the varied tapered angle on the reflectance spectra of grating was investigated. Meanwhile, affects of different parameters like the grating thickness, membrane thickness, grating period, filling factor, incident beam based on a certain tapered angle were also analyzed on reflectance spectra of the GaN grating. Rigorous coupled wave analysis (RCWA) was used as theoretical principle for numerical simulations on the GaN grating model in this study. The results of this report are very useful for fabricating GaN reflectance photonic devices, such as refractive index sensor, couplers and so on. [ABSTRACT FROM AUTHOR]

Introduction: Although depression is commonly accompanied by cognitive deficits, the underlying mechanism remains unclear. One possibility is that such deficits are related to abnormal brain network connections. The purpose of this study was thus to investigate changes in brain functional connectivity (FC) in depression and its relationship with cognitive deficits.Methods: We enrolled 37 first-episode MDD patients and 53 matched healthy controls (HC). All participants completed clinical and neurocognitive assessments and underwent resting-state functional MRI. Seed-based analysis was used to define the dorsolateral prefrontal cortex (DLPFC) and FC analysis was then performed. We used bias correlation to analyze the correlation between FC and clinical and neurocognitive scores.Results: MDD patients showed increased FC of the right DLPFC with the left inferior temporal gyrus, left cuneus, right inferior frontal gyrus, right anterior cingulate cortex, left BA39, right angular gyrus, right precuneus, left middle frontal gyrus, and right precentral gyrus. MDD patients also showed stronger FC in the left thalamus and reduced FC between the left superior occipital gyrus and left DLPFC seed region. Interestingly, increased FC was related to disease severity (with the right precentral gyrus) and social cognitive dysfunction (with the right angular gyrus) in MDD patients.Limitations: The sample size was relatively small and it is unclear how age may influence FC changes in patients with depression.Conclusions: These findings support changes in FC of the DLPFC in early MDD patients related to cognitive function. FC is a potential biomarker for the diagnosis of MDD. [ABSTRACT FROM AUTHOR]

A series of pyridine-functionalised bis(benzoimidazolium) dichlorides, dibromides and dihexafluorophosphate with different alkyl bridged length (n = 2-4) were synthesised in high yield. All the compounds are new and fully characterised by 1H and 13C NMR, IR and elemental analyses. [ABSTRACT FROM AUTHOR]

The spectral characteristics of carbon nanotubes is essential for the development of optoelectronic components and sensors with application in many fields. The linear polarizability absorption spectra of the carbon nanotube with a twisted angle have been calculated by using the tight-binding model and sum-over-state method. First, a structural model of carbon nanotubes based on PPP(Pariser-Parr_Pople) was established, then a certain carbon atom was moved to a position where the carbon nanotubes are angled, and the torsional carbon nanotube structure model was calculated based on the change in bond length. Finally, the absorption spectrum at different twisted angles based on SOS(Sum-over-State) was calculated, and then the detailed analysis was made. It is found that the twisted angle has real impact on the absorption spectra of different types carbon nanotubes. The torsional angle leads to changes in the position and number of absorption peaks of the carbon nanotubes. Its influence on absorption spectra of different types of carbon nanotubes is different, but mainly concentrated in the low frequency region. Exactly, altering the twisted angle has an important effect on the absorption spectra of the carbon nanotube. This work offers a guidance of fabricating carbon nanotubes in the applications of photonic device in many fields. [ABSTRACT FROM AUTHOR]

Background: Nesolotis Miyatake, 1966 shows a high diversity in the Oriental Realm., New Information: Here, we recorded this genus in Laos for the first time and provided a detailed description of a new species, namely Nesolotislaotica Lv & Wang, sp. nov., (Lanlan Lv, Xingmin Wang.)