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Graphene is an advanced carbon functional material with inherent unique properties that make it suitable for a wide range of applications. It can be synthesized through either the top–down approach involving delamination of graphitic materials or the bottom–up approach involving graphene assembly from smaller building units. Common top–down approaches are exfoliation and reduction while bottom–up approaches include chemical vapour deposition, epitaxial growth, and pyrolysis. A range of materials have been successfully used as precursors in various synthesis methods to derive graphene. This review analyses and discusses the suitability of conventional, plant- and animal-derived, chemical, and fossil precursors for graphene synthesis. Together with its associated technical feasibility and economic and environmental impacts, the quality of resultant graphene is critically assessed and discussed. After evaluating the parameters mentioned above, the most appropriate synthesis method for each precursor is identified. While graphite is currently the most common precursor for graphene synthesis, several other precursors have the potential to synthesize graphene of comparable, if not better, quality and yield. Thus, this review provides an overview and insights into identifying the potential of various carbon precursors for large-scale and commercial production of fit-for-purpose graphene for specific applications.

This document is a correction notice for an article titled "Examining Transcriptomic Alterations in Rat Models of Intracerebral Hemorrhage and Severe Intracerebral Hemorrhage." The correction involves a mistake in Figure 1A, where the labels of ICH and Severe ICH were swapped. The corrected image now accurately reflects the conditions represented. The authors state that this correction does not affect the scientific conclusions of the study. The original publication has been updated to include the correction. [Extracted from the article]

BackgroundA complex interplay between different cell types in the epithelium leads to activation of the luminal acidifying capacity of the epididymis, a process that is crucial for sperm maturation and storage. Basal cells sense the luminal angiotensin II (ANG II) and stimulate proton secretion in clear cells through nitric oxide (NO). Our previous study has shown the chemokine regulated upon activation normal T-cell expressed and secreted (RANTES) was expressed in the F4/80 positive macrophages of human epididymis. The objective of this study was to explore the involvement of RANTES in regulating the luminal acidification in the rat epididymis.MethodsThe role of RANTES was investigated by in vivo perfusion with recombinant RANTES, Met-RANTES, and PBS of different pH values. Furthermore, rats vasectomy was performed to alter the epididymal luminal pH. RIA was used to measure the tissue homogenate ANG II concentration. Real time-PCR and western blot were employed to examine the expression levels of AGTR2, RANTES, CCR1, CCR5, and iNOS in epididymis.ResultsRANTES was restricted to the basal macrophages of epididymal ducts and co-localized with its receptors CCR1 and CCR5. Both V-ATPase and iNOS were up-regulated in the cauda epididymis after perfused with recombinant RANTES, while the antagonist Met-RANTES perfusion led to a complete abrogation of the increased expression of V-ATPase in the apical membrane of clear cells and iNOS in macrophages. Upon alkaline perfusion, RANTES expression was significantly increased and the apical accumulation of V-ATPase in the clear cells was induced in the cauda epididymis. The luminal pH in the cauda epididymis increased after vasectomy. The concentration of the ANG II and the expression levels of AGTR2, RANTES, CCR1, CCR5, and iNOS dropped in the cauda epididymis following vasectomy.ConclusionUpon the activation of basal cells, RANTES might induce the NO release from macrophages by interacting with its receptors, which increases proton secretion by adjacent clear cells. Thus, RANTES is possible to participate in the crosstalk among basal cells, macrophages and clear cells for the fine control of an optimum acidic luminal environment that is critical for male fertility.

Metasurface‐based vectorial holography manifests itself as an advanced platform for large‐capacity information storage, holographic display, and cryptography. However, a convenient and effective reconfigurable vectorial hologram generation mechanism still remains a challenge. Here, a rotation‐driven reconfigurable vectorial holography scheme is developed via a dual‐layer hybrid metasurface device, in which radiation‐type and birefringent metasurfaces are cascaded hybridly. Thus, reconfigurable and highly customizable intensity and polarization response of holograms in the 3D space is achieved. Rotatable radiation‐type metasurface (RTM) serves as an incidence‐wavefront modulator to excite the non‐rotatable birefringent metasurface (BM). The gradient descent optimization inverse design method is introduced to achieve the high‐efficiency reconstruction of the Jones vector and Jones matrix distribution on both RTM and BM. On this basis, numerical analysis and experimental verification of 3‐D reconfigurable vectorial holography are demonstrated in the microwave region. This scheme implies a new paradigm for 3‐D reconfigurable vectorial holography and can lead to advances in high‐capacity optical display, switchable meta‐devices, and cryptography. [ABSTRACT FROM AUTHOR]