Graphene, an extraordinary tow-dimensional carbon nanostructure, has attracted global attention due to its electronic, mechanical, and chemical properties; therefore, there is a need to find out an economical mass production method to produce graphene. In the present research, the aim is to find out optimal conditions for exfoliation of few-layers graphene (FLG) in a water–ethanol green solution. We varied different parameters of the ultrasonic probe like power quantity and time duration of sonication to investigate the effects on the number of graphene layers and density of graphene in the solution. Also, an attempt has been made to predict the acoustic pressure distribution by solving the wave equation in various output powers of the ultrasonic probe (sonotrode) using numerical simulations. The simulations and experimentations verify each other. Concluding that modifying the output power at the same condition will significantly alter the acoustic pressure inside the sonoreactor. The difference in acoustic pressure at 90% output power of our experimentations is much higher than in other conditions. Experimentation results utilizing UV–visible spectra, SEM (Scanning electron microscope), TEM (Transmission electron microscope) images and Raman spectrum indicate that the minimum thickness and maximum exfoliation for these samples are acquired for sonication at 90% of the maximum effective output power of the sonicator being 264 W for 55 min. The firstly pioneering experiments have been carried out on micro mechanically cleaved monolayers, but micro mechanical method has the disadvantages of low production yield and poor throughput. In order to utilize graphene for future industrial applications requiring large-scale and high-output processing methods are required6. At present, the reduction of graphene oxide is the preferred scalable method for the preparation of graphene. In this method, the oxidization of graphite by following Hummers modified method, followed by exfoliation of graphite oxide in water, to give aqueous dispersions of graphene oxide (GO) and further the oxidation can be removed by thermal or chemical reduction8. However, the reduction of graphene oxide still retains a high defect density, which degrades their properties.Recently, graphene as a single atomic layer of carbon has attracted significant attention for research due to its unique nanostructure, mechanical, electric and novel thermal properties10. Graphene sheets can be extracted through sonication11 or shear exfoliation12 in an aqueous surfactant solution and certain organic solvents. Several groups have shown that graphene can be prepared in N-methyl-2-pyrrolidone13 (NMP), and dimethylformamide14 (DMF), to produce graphene nano-sheets. These solvents have surface tension close to 40 mJ m−2 and are suitable for direct exfoliation of graphite into FLG15. However, these solvents have high boiling points that limit their viability for real use. Thus, dispersion of graphene in low boiling point solvents is useful in many applications, such as nanocomposites16 nanoplasmonics19, smart coating20, and high-frequency devices23. Many reports present the effect of sonication parameters on produced MoS2 nano-flakes and graphene in DI water-ethanol26. A simple, low-cost, and energy-effective sonication to exfoliate natural graphite flakes in ethanol in a short time sonication is reported27. Studies are aimed at determining the rate of exfoliation of various forms of graphite and its oxide using the top-down method and using UV–Vis spectroscopy for a deeper understanding of the electronic transition are presented29. In another article, one can find out UV–Vis. method to measure the percentage of few-layer sheets in GO dispersions quickly and cheaply30.Most researchers have focused on the direct solution-phase exfoliation of natural graphite flaks to overcome the limitation of graphene oxide. A few layers of graphene were synthesized by evaporating polystyrene at atmospheric pressure by the chemical vapor deposition (APCVD) methodIn this research study, an attempt has been made to predict the acoustic pressure distribution by solving the wave equation in various output power of the ultrasonic probe. Simulations have been carried out by using a numerical model. Then Graphene is prepared via the LPE (liquid phase exfoliation) method utilizing the ultrasonic probe. Then we investigated the various effects of the output power, sonication time duration for the same concentration to find the optimal condition to achieve more graphene with thinner layer from graphite powder. Then simulations are compared with experimental results.In this section material method and the samples preparation are presented.All the chemicals used in this project were research-grade and deionized water (DI) throughout the experiments. The used liquid medium is a green solution prepared by a mixture of 65% DI Water and 35% Ethanol. The sonication is carried out using the ultrasonic processor with a titanium probe (Tip) of 22 mm in diameter (FAPAN-1200UPS model made in Iran by FAPAN Co. Ltd.), operation frequency 20 kHz, and nominal power of 1200 W (RMS power of 300 W).31. But water has a surface tension of about 72 mJ m−2. The range of solvent surface tension that can better exfoliate graphene32 is 40–50 mJ m−2. Optimal surface tension to minimize interfacial tension between graphene and solvent is a mixture of water and a solvent with lower surface tension. Ethanol is a good choice because it has a low boiling point with surface tension close to 22.1 mJ m−2. The 65/35 volume ratio for DI water/ethanol is calculated using the Connors-Wright equation with the surface tension of the solution to be 46 m J m−2 for making binary aqueous organic solutions27. The beaker is kept in an ice-water bath to reduce evaporation of the ethanol due to an increase in the temperature of the solution during the sonication process. Furthermore, the sonicator is adjusted to pulse mode of 50% to prevent overheating. So, the total effective sonication time for preparing the samples is 55 min. The thick flakes are eliminated by centrifugation using a bench top centrifuge: the first step is done for 30 min at 3000 rpm, and then the top 3/4th of the dispersion is retained for the next step, then the rest of the liquid is discarded. Afterward, the second step is carried out again for 15 min at 3600 rpm, and finally, the top 3/4th of the supernatant is collected for the following analyses.Experimentation for all samples is carried by immersing 250 mg of graphite powder added into 125 mL of water–ethanol in a 150 mL glass beaker. We aim to utilize a “green solvent” in order to minimize the environmental impacts. As expected, water is the greenest solventIn this section, an attempt has been made to predict the acoustic pressure distribution by solving the wave equation in various output power of the ultrasonic probe. Simulations have been carried out by using a numerical model. The Computational Fluid Dynamics is a powerful tool that can be used to optimize the characteristic of the sonoreactor. The present numerical study aims to deliver a detailed explanation and instructions to model the sonoreactor under different operating conditions. In the following section, the computational domain, the physical models, and the boundary conditions will be presented. For such an arrangement, it is usually assumed that the highest local pressure value is reached in the close vicinity of the probe. The intensity 34.As the distance from the probe increases, the intensity decrease according to an area into which it is spread in a conical shape. For calculation of the intensity distribution, the distribution of ultrasonic pressure amplitude The acoustic pressure can be obtained by solving wave equation. If linear wave propagation is assumed and the shear stress is neglected which is corrected for liquids and gases, the wave equation has the form:ω is the angular frequency.The pressure p is considered time harmonic i.e.,An axisymmetric 2D section of the ultrasonic processing cell with an ultrasonic probe is used as the modeling geometry. Figure 35.The pressure at the probe tip is calculated from the equation The acoustic pressure distribution zone in the solution is quantified by estimating the area of the regions within the ultrasonic processing cell. The output power is identified to be influential in determining the size of the resultant acoustic pressure distribution zone. The output power for the validation study is listed in Table It is predicted that this output power would be the most effective among the considered range of parameter for the performance of acoustic pressure distribution for ultrasonic liquid processing. For the acoustic pressure analysis, various output powers were selected and the maximum and minimum acoustic pressure and pressure difference i.e. entclass1pt{minima6 Pa and the minimum pressure is − 0.43 × 106 Pa. While, at 90% of output power (~ 264 W) the maximum pressure is 1.4  × 106 Pa and the minimum pressure is − 1.3 × 106 Pa which is supported by the earlier report32. The difference between the maximum and the minimum pressures  in the optimum sonication time of 55 min. From the previous results of the experimentation in this research, the best condition is observed to use a solution with a volume of 125 CC. The effect of changing the output power of sonication in detail by measuring their UV–Vis absorption spectra and SEM are recorded.* transitions of graphene and graphite34. Figure The optical characterization of the graphene sheets is performed with a Perkin-Elmer model lambda 25 spectrometer. Using the UV–Vis spectrometer absorption spectrum one can estimate the approximate thickness of the layers or equally the approximate number of layers. The UV–Vis absorption spectra of graphene samples for 40–90% of the maximum power of the continuous radiation mode are shown in Fig. This result is also confirmed by SEM (ESEM Philips XL30) images, as shown in Fig. 32, the change of output power alters the acoustic pressure range , multi-layer (4–10 layers), and thick layer (> 10 layers) graphene by previous report35.From simulation of acoustic pressure distribution, we found that at the same conditionPa Table  reveals Influence of the effective time duration of the sonication for graphene dispersions in the water–ethanol solutions at 264 W power is studied to find out the range of graphene flakes production in different sonication time duration of 25, 35, 45, 55, and 65 min, which the results are shown in Fig. The SEM micrographs shown in Fig. All findings in this research result in the fact that our most delicate graphene samples in these experimentations are acquired at; power of 264 W, pulse duration of 50% and 55 min irradiation duration which is the “optimum situation” for producing graphene flakes.The structural characterization of the graphene nano-sheets is further examined by TEM Zeiss EM10C, 100kv). Figure C, 100kv.−1, the G peak at ~ 1586 cm−1, and the 2D peak at ~ 2655 cm−1 are existing. Therefore, Raman spectrum of the sample as shown in Fig. For more reassurance, the analysis of Raman spectroscopy is used. Figure s report , the numWe studied the effects of the critical ultrasonic LPE parameters, i.e., power and time duration of sonication, on the quality and yield of FLG flakes produced in DI Water–Ethanol in a vessel with 150 mL of water/ethanol-powder solution. In conclusion, graphene produced by sonication is pure graphene and does not need reduction from GO or purification by washing out chemicals. A distribution of acoustic pressure events throughout the treated volume assisted by acoustic pressure difference is a critical factor in producing more quantity and high-quality FLG flakes. The numerical simulations approve the experimental results, which is an increase in the sonicator radiation power increases the conversion of graphite to graphene due to an increase in pressure differences. In addition, for 264 W of sonicator power, the shift in absorption spectra from 266 to 270 nm occurs, which reveals graphene exfoliation with few-layer (1–3 layers). The UV–visible technique is proven to be very effective in studying the number of layers exfoliated and detecting the difference in conjugated polyenes that affect π to π* plasmon peak.Characterization by UV–visible, SEM, TEM, and Raman spectrum shows that the few-layer graphene for sonication time of 55 min is the optimum for high-quality pure graphene exfoliated from graphite powder for this setup. Graphene with a sonication time of 55 min has a thinner and larger sheet compared to sonication for less or more time duration. Therefore, our findings from the analyses presents the optimum operating parameters for sonicator with the probe of 22 mm in diameter and pulse mode being 50% with 250 mg of graphite in the 125 ml of water–ethanol solution and 150 mL beaker to achieve few-layer graphene flakes with good yield are obtained at 264 W of power, and 55 min of sonication time duration.


Idiopathic pulmonary fibrosis (IPF) is a representative disease that causes fibrosis of the lungs. Its pathogenesis is thought to be characterized by sustained injury to alveolar epithelial cells and the resultant abnormal tissue repair, but it has not been fully elucidated. IPF is currently difficult to cure and is known to follow a chronic progressive course, with the patient’s survival period estimated at about three years. The disease occasionally exacerbates acutely, leading to a fatal outcome. In recent years, it has become evident that lipid metabolism is involved in the fibrosis of lungs, and various reports have been made at the cellular level as well as at the organic level. The balance among eicosanoids, sphingolipids, and lipid composition has been reported to be involved in fibrosis, with particularly close attention being paid to a bioactive lipid “lysophosphatidic acid (LPA)” and its pathway. LPA signals are found in a wide variety of cells, including alveolar epithelial cells, vascular endothelial cells, and fibroblasts, and have been reported to intensify pulmonary fibrosis via LPA receptors. For instance, in alveolar epithelial cells, LPA signals reportedly induce mitochondrial dysfunction, leading to epithelial damage, or induce the transcription of profibrotic cytokines. Based on these mechanisms, LPA receptor inhibitors and the metabolic enzymes involved in LPA formation are now considered targets for developing novel means of IPF treatment. Advances in basic research on the relationships between fibrosis and lipid metabolism are opening the path to new therapies targeting lipid metabolism in the treatment of IPF. Vβ1/αVβ6 . Th. Th72]. 2 (PGE2), leading to the long-lasting view that eicosanoids are involved in the pathogenesis of IPF [2 synthesis, is low in the lungs of IPF patients [2 is one of the lipids having been actively studied as a lipid with antifibrotic activity. PGE2 has been reported to suppress the proliferation of fibroblasts and their transformation into myofibroblasts and to reduce collagen production [2 was suggested to work protectively against fibrosis [2 level, suggesting the possibility that PGE2 works in physiological defensive reactions. When PGE2 was administered in advance to bleomycin in an animal model of bleomycin-induced interstitial pneumonia, the collagen level and the histological fibrosis score (Ashcroft score) on 21 days after the dose showed improvement, while administration of PGE2 after the bleomycin dose failed to manifest therapeutic efficacy [2 has physiological antifibrotic activity. In the lungs, PGE2 is produced by epithelial cells and fibroblasts [2 [2 synthesis [2 is considered to manifest protective activity during the early phase of fibrosis and can serve as a critical target of IPF treatment.The cells derived from IPF patients have been reported to show reduced levels of cyclooxygenase-2 (COX-2) and prostaglandin Es of IPF ,74. It hpatients . PGE2 isoduction . In a mofibrosis . The broefficacy . These rroblasts , and a slasts [2 . There iynthesis . Thus, PWAF (senescent cell markers) positive [LTC4S, and LTA4H in human fibroblasts and elevation of cysteinyl leukotrienes (cysLTs) in conditioned medium (CM) [ALOX5) but no elevation of the enzymes involved in the synthesis of prostaglandins such as PTGS2 (COX-2), PTGDS, and PTGES [COL1A2 and αSMA increased, and this change was inhibited by a 5-LOX inhibitor (zileuton) but not by a COX-2 inhibitor (NS-398) [COL1A2 expression in fibroblasts, while montelukast, known to inhibit cysteinyl leukotriene receptors 1 (CysLT1), suppressed COL1A2 [The senescent cells, which are unable to proliferate as a result of aging, are considered one of the significant etiological factors for IPF, and it has been reported that IPF can be characterized by an increase of alveolar epithelial type II cells (AECII) which are p53 and p21positive . Lipid cium (CM) . The sennd PTGES . It is p(NS-398) . These rd COL1A2 ,82. Therd COL1A2 ,84, prov4 (LXA4) is an eicosanoid metabolized by 5-LOX and 15-lipoxygenase (15-LOX). LXA4 has been shown to suppress TGFβ1-dependent collagen secretion, αSMA expression, and cell proliferation in fibroblasts derived from IPF patients. It is desirable that LXA4 is further studied from now on [Similar to LTs, lipoxin Am now on .2  has also been reported to be antifibrogenic. Iloprost, a prostacyclin analogue, has been reported to have suppressed profibrotic cytokines  and fibrosis in a mouse model of bleomycin-induced fibrosis [Of the other eicosanoids, prostaglandin Ifibrosis .2α (PGF2α) is considered to be profibrogenic. The level of PGF2α in the BALF was higher in IPF patients than in the disease control group [2α receptor “prostaglandin F (PGF) receptor (FP)” (−/−Ptgfr), bleomycin-induced pulmonary fibrosis was suppressed [2α is involved in the pathogenesis of pulmonary fibrosis and can serve as a target for treatment of pulmonary fibrosis.Prostaglandin Fol group , and thiol group . In miceppressed . Thus, P2 (PGD2) is catalyzed by hematopoietic prostaglandin D synthase in the presence of glutathione and produced primarily in activated mast cells and T cells, and has a suppressive effect on fibrosis [2 resulted in c-AMP-mediated suppression of TGFβ-induced type I collagen secretion. A similar suppressive activity has been observed also with BW245C, a PGD2 receptor (DP-receptor: DP1) agonist, thus suggesting the involvement of PGD2-DP1 signals in suppression of fibrosis [2 receptor “chemoattractant receptor homologous with T-helper cell type 2 cells (CRTH2)” is also considered to be involved in the suppression of fibrosis. CRTH2 is expressed in type 2 cytokine-producing T cells and in group 2 innate lymphoid cells (ILC2). CRTH2 deficient mice (CRTH2−/−) showed aggravation of bleomycin-indued fibrosis as well as elevation of inflammatory cells in BALF and elevation of lung tissue Col1a1. The transplant of splenic δγT cells into CRTH2−/− mice resulted in the suppression of fibrosis, suggesting that CRTH2 in these cells affects fibrosis [Prostaglandin Dfibrosis ,89. The fibrosis . Anotherfibrosis .1–S1P5) are known, all assuming the form of seven-transmembrane trimer type G protein-coupled receptor  RNA, a reduction in sphingosine-1-phosphate (S1P) levels was induced and collagen production was suppressed [When studied in mice, administration of bleomycin elevated the lung tissue ASM activity, accompanied by elevation in Cer and acid ceramidase (AC) activity. In ASMppressed . This reWhen human fibroblasts were stimulated with TGFβ or bleomycin, the levels of mitochondrial reactive oxygen species (mtROS) and transcription factors, such as Hippo/yes-associated protein (YAP), fibronectin (FN), and αSMA, were elevated. Inhibition of Sphk1 or YAP resulted in a decrease of mtROS and less expression of FN and αSMA. Furthermore, inhibition of each of S1P and YAP resulted in a similar decrease of mtROS and less expression of FN and αSMA . On the There is a report demonstrating a significant elevation of the S1P level in the serum and BALF of IPF patients. S1P has additionally been reported to have roles in epithelial-mesenchymal transition (EMT) in stimulated-AECII, cell proliferation, and collagen production .−/−) showed enhanced permeability across the pulmonary vessels. Intratracheal administration of bleomycin to EC-S1pr1−/− mice resulted in enhanced pulmonary vascular permeability and aggravation of fibrosis compared to wild-type mice [Regarding the activity of S1P on vascular endothelial cells, the effects in reducing vascular permeability and the protective activity are known . The eleype mice . It seemype mice .A sphingosine analogue, FTY720 (Fingolimod) is a drug known to be phosphorylated by sphingosine kinase 2 and to function as an S1P analogue . It has Elongation of long-chain fatty acid family member 6 (Elovl6), a kind of fatty acid elongation, has been reported to aggravate bleomycin-induced pulmonary fibrosis through disturbing the balance in fatty acid composition . Elovl6 Phospholipid profiles in the serum of IPF patients have also been measured. Analysis of the serum lipids in IPF patients by ultra-high performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLCHRMS) revealed elevated levels of lysophosphatidylcholine (LPC) . That reLipid composition has also been studied in the IPF-affected lung tissue, revealing the elevation of palmitic acid (16:0) and stearic acid (18:0) . In a stThe role of other lipids has also been investigated in preclinical studies . Exposur−/−) mice, the level of low-density lipoprotein (LDL) was markedly high, and the administration of bleomycin resulted in the rapid onset of intense fibrosis. LDL was thus estimated as a factor responsible for the induction of apoptosis and TGFβ [Statins are extensively used for the treatment of hypercholesterolemia during clinical practice. They have recently been shown to have anti-inflammatory activity as well. In a mouse model of bleomycin-induced fibrosis, treatment with pravastatin suppressed the expression of TGFβ, CTGF, and RhoA as well as the expression of a fibrosis marker, hydroxyproline . In receand TGFβ . Also, cand TGFβ .There is a report that mitochondrial dysfunction in type II alveolar epithelial cells exacerbated fibrosis . In thatWe previously reported that the phosphatidylserine decarboxylase (PISD), an enzyme for lipid metabolism found in mitochondria, was decreased by TGFβ, leading to a change in the phospholipid composition. In fibroblasts, knocking down the PISD resulted in the elevation of αSMA and collagen production, suggesting that PISD may be contributing to the mechanism for fibrosis through the adjustment of phospholipids .Myofibroblasts are an important source for collagen production. Metformin, a drug for the treatment of diabetes mellitus, has been reported to have the potential of inducing the transformation of myofibroblasts into lipid droplet-containing interstitial fibroblasts (lipofibroblasts) mediated by AMP-activated protein kinase (AMPK). COL1A1 expression is lower in lipofibroblasts than in myofibroblasts, and the effect in maintaining AECII (known to be involved in lung regeneration) is expected of lipofibroblasts. Thus, lipofibroblasts are promising as a target for the treatment of pulmonary fibrosis from now on ,126.As illustrated above, lipid metabolism is involved in the pathogenesis of fibrosis. Novel treatment methods are being developed as mentioned above, including the evaluation of cell-based therapy. Cell-based therapy is an approach of regenerative medicine expected to manifest anti-inflammatory activity through the administration of stem cells. When regenerative medicine is considered, it is also essential to evaluate the lipid composition in each product used for regenerative medicine . SuppresThe relationship between vascular meshwork and fibrosis during IPF pathogenesis has been actively analyzed, yielding reports that lung tissue fibrosis is affected by the stimulation of fibroblasts mediated by capillary endothelial cells  and thatWhen regenerative medicine is considered, it needs to be borne in mind that the lipid composition is likely to change depending on the conditions and that attention is needed to be paid not only to the composition but also to the distribution of lipids.The LPA cascade has been attracting close attention in recent years because it has the potential of explaining the pathogenesis of IPF and being utilized for therapeutic strategy. The BALF of IPF patients is known to be significantly rich in LPA , and LPAThe pathway for LPA metabolism is diverse , and a rUsing an animal model of bleomycin-induced interstitial pneumonia, we analyzed the profiles of PC, PE, and LPC in the serum and BALF. The levels of PC, PE, and LPC in the BALF were found to be significantly elevated for many fatty-acid-binding patterns (unpublished data). These results suggest the possibility that phospholipids, such as PC and PE, were released locally in the alveolar epithelium and underwent metabolism into lysophospholipids. If this finding is combined with the past report that the lung tissue’s chromatic response to ATX was elevated in IPF patients , it seemResembling the migration of fibroblasts to a certain site of the fibrin matrix to form granuloma there during the course of skin injury, it is known that fibroblasts accumulate in the fibrin-rich exudate from airspaces during the course of IPF . The BALStimulation of fibroblast’s chemotaxis by LPA was inhibited by an LPA1 inhibitor, Ki16425 , indicatThe LPA/LPA1 cascade also affects the epithelial cells. Apoptosis of epithelial cells is considered to be involved in the onset of IPF . LPA1 KO−/−) mice, studied as a model of bleomycin-induced interstitial pneumonia, showed suppressed expression of fibronectin and αSMA, accompanied by decreases in lung tissue collagen and pulmonary vascular leakage and improvement of the survival rate [Evaluation has also been made on LPA2. LPA2 KO , i.e., ectonucleotide pyrophosphatase/phosphodiesterase family member 2 (Enpp2), is an enzyme involved in LPA formation and has been reported to be expressed abundantly in the alveolar epithelium, fibroblastic foci, and alveolar macrophages of IPF patients  Figure . It has poplasia . For thipoplasia . In the poplasia .ClinicalTrials.gov  [IM136003 (NCT01766817) is a phase 2 clinical trial on the use of BMS-986020 for IPF. Between April 2013 and February 2016, 373 participants were enrolled to the trial and 143 of them were randomized to three groups  group, n = 48; BMS-986020 600 mg bis in die (bid) group, n = 48) for this phase 2, multicenter, randomized, double-blind trial involving patients with IPF having FVC 45–90% and diffusing capacity for carbon monoxide (DLCO) 30–80%. The primary endpoint was the change from baseline in FVC rate to Week 26. FVC reduction was significantly smaller in the BMS-986020 600 mg bid group than in the control group  conducted previously is presented first. During the period from March 24, 2016, to May 2, 2017, screening was conducted on 72 patients and 23 of them were enrolled to the trial. Six patients were allocated to the placebo group and 17 patients to the GLPG1690 600 mg qd group, each planned to receive 12-week oral treatment according to the protocol . The meaClinicalTrials.gov. It seems that the all-cause mortality was probably related to the discontinuation of this trial.In the phase 2 trial, the safety of GLPG1690 comparable to a placebo was demonstrated, and the reduction in respiratory function at Week 12 (a secondary outcome) was also suppressed. On the basis of these results, two phase 3 clinical trials, i.e., ISABELA1 (NCT03711162) and ISABELA2 (NCT03733444), were started in November 2018 . Both trBBT-877 is an ATX inhibitor on which antifibrotic activity and toxicity have been checked in animals . On FebrIn recent years, mass spectrometry techniques have been widely used to identify lipids at the molecular level for samples derived from IPF patients. As mentioned above, lipid metabolites not only serve as bioactive substances, but also may have potential value as supplementary tests for IPF diagnosis . In the Lipid-targeted IPF therapies may be differently affected for an individual lipid profile of each patient. For example, they may be more effective for patient groups in which LPA signaling is a major contributor to the pathophysiology, and vice versa. Measurement of patients’ BALF and serum lipid profiles might be useful as a predictor for therapeutic efficacy. When various targeted therapeutic agents were used in IPF, their combined efficacy would be examined. In addition, appropriate dosing of those drugs may be examined, and individualized treatment options may be selected based on background factors such as age, gender, and lipid profiles of patients in IPF.This review paper has outlined the pathogenesis and treatment of IPF and summarized the involvement of lipids in the pathogenesis of IPF attracting close attention in recent years. The cascade related to LPA is now attracting particularly close attention, and the authors have described in this paper not only the involvement of LPA in IPF pathogenesis but also the clinical trials under way on this lipid. The pathogenesis of IPF is difficult to explain by a single mechanism. The disease develops under a complex involvement of chronic alveolar injury, genetic predisposition, and environmental factors. The pathogenesis of IPF involving lipid metabolism has been outlined in this paper, but the etiology of this disease can include diverse factors in addition to the factors mentioned above, e.g., regulatory T cells , ILC2 1, and celInhibition of ATX or LPA receptors differs from the target of pirfenidone or nintedanib and may serve as a valid strategy for the treatment of IPF from now on. Because the LPA pathways are involved also in the homeostasis of organisms , treatmeAlthough IPF is a disease with a poor prognosis, its pathogenesis has been increasingly unveiled in recent years, and there have been increasing efforts for developing novel methods of treatment. Hopefully, lipid metabolism in the mechanism of lung fibrosis will be further elucidated, and therapies targeting it will lead to real-world clinical practice and help overcome IPF.


B = 30 T), graphene can support the QH effect up to room temperature (RT), concomitant with a non-negligible population of acoustic phonons with a wave-vector commensurate to the inverse electronic magnetic length. Here, we demonstrate that graphene encapsulated in hexagonal boron nitride (hBN) realizes a novel transport regime, where dissipation in the QH phase is governed predominantly by electron-phonon scattering. Investigating thermally-activated transport at filling factor 2 up to RT in an ensemble of back-gated devices, we show that the high B-field behaviour correlates with their zero B-field transport mobility. By this means, we extend the well-accepted notion of phonon-limited resistivity in ultra-clean graphene to a hitherto unexplored high-field realm.The quantum Hall (QH) effect in two-dimensional electron systems (2DESs) is conventionally observed at liquid-helium temperatures, where lattice vibrations are strongly suppressed and bulk carrier scattering is dominated by disorder. However, due to large Landau level (LL) separation (~2000 K at  Monolayer graphene can support the quantum Hall effect up to room temperature. Here, the authors provide evidence that graphene encapsulated in hexagonal boron nitride realizes a novel transport regime where dissipation in the quantum Hall phase is mediated predominantly by electron-phonon scattering rather than disorder scattering. The use of hBN as atomically-flat encapsulating dielectric, in particular, permits a drastic reduction of extrinsic disorder in graphene devices2, leading to the observation of zero-field transport regimes dominated by either electron-electron3, electron-hole4 or electron-phonon (e-ph) interaction5, which manifest over different carrier density and temperature ranges. Toward RT (T ~ 300 K), the scattering of electrons with acoustic phonons was theoretically identified as the main intrinsic contribution to the electrical resistivity in graphene8, implying a carrier mobility exceeding 105 cm2V−1s−1 at low carrier concentration (n < 1012 cm−2). While such figures could already be inferred from early data on disordered SiO2-supported graphene (~104 cm2V−1s−1 mobility)10, at present, the reach of the zero-field acoustic-phonon-limit is firmly established as a generic property of high-quality graphene devices5, also when encapsulated in hBN crystals from different sources11 or engineered to high doping levels (n > 1013 cm−2)12. Notable exceptions to the cleanness-implies-high-RT-mobility scenario are suspended graphene samples, where flexural phonons dramatically contribute to carrier scattering leading to a T2 behaviour of the resistivity13, and rotationally faulted graphene bilayers close to magic-angle, showing strong phonon-driven T-linear resistivity14. The difference between freely suspended graphene and graphene encapsulated in hBN is due to the fact that in the latter case van der Waals interaction between graphene and substrate makes flexural phonons harder, suppressing an intrinsic rippling instability15.Van der Waals heterostructures of graphene and hBN have recently granted experimental access to novel phenomena in condensed matter16 at temperatures close to RT. In this sense, we note that previous literature on the RT-QH effect in graphene20 exclusively includes experiments on SiO2-supported devices, precluding such investigation.In this work, we address the fundamental question whether the e-ph mechanism in clean graphene could also govern the electrical transport in the QH regimeEF) lies on the localised states between two LLs, formed in a perpendicular magnetic field and separated by an energy gap ΔLL. The interplay between this energy scale and the thermal energy kT governs the basic phenomenology of the electrical transport in the QH regime. When ρxx) when measured in four-probe configuration . The pre-factor to the exponential term, ρ0, which is often not considered explicitly, determines the magnitude of the T-activated resistivity . In conventional 2DESs, the small ΔLL leads to a complete suppression of the QH effect within a few K25, where the Eph-controlled phonon population can be considered negligible. Although the low electronic mass in 2DESs such as InSb26 and HgTe29 enables the observation of the QHE up to liquid-nitrogen temperature, this is insufficient to ensure Eph and the corresponding T-dependent excitation probability for acoustic phonons in graphene at B = 30 T are shown in Fig. T-activated resistivity . The Hall conductivity (σxy) presents weak slope changes around filling factors ν = ±2 (Vg ~±20 V), while the shelves-like features at low carrier concentration originate from the onset of electron-hole coexistence in the highly-degenerate N = 0 LL30. ρxx, in addition to the pronounced maximum around the charge neutrality point (CNP), shows two sizable minima  over the whole n range. Importantly, sample D3 shows a μ(n) dependence comparable to the data of ref. 5 (dash-dotted line), demonstrating the standard fingerprint of phonon-limited RT mobility in zero magnetic field12 . The overall high quality of the samples is also supported by the observation of fractional QH states at liquid-helium temperature . In Fig. 32) and the charge inhomogeneity in the CNP region, estimated as the usual n* parameter33 . In addition, as for refs. 34, the linear μ−1(n*) dependence  span a low-disorder range unexplored in previous RT-QH experiments, and (ii) present a well-defined disorder type, with increasing impact along the D4-to-D1 sequence.In Fig. T on the Landau-quantized electrons in graphene at B = 30 T. Toward RT, the broadening of the Fermi-Dirac distribution around EF  ensures excited charge carriers from both the N = 0 and N = 1 LLs, across the giant gap ΔLL. Accordingly, the local resistivity minimum at filling factor ν = 2 leaves zero and displays increasing finite values, as shown in the experimental curves of Fig. T-dependence of ρxx (ν = 2) for samples D1-4, at selected magnetic fields  in graphene on SiO2), and two theoretical calculations defining different dissipation limits (continuous lines). In both cases we take an activation energy equal to ΔLL/2: this was shown to be accurate for high B-fields in ref. 20 and should hold true for clean graphene with reduced LL broadening. The upper line (yellow) assumes the universal conductivity pre-factor due to long-range disorder (2e2/h)23, multiplied by a factor 4 to take into account the LL degeneracy of graphene. The lower line (dark cyan) is based on the work by Alexeev et al.24, who calculated the conductivity mediated by two-phonon scattering for graphene in the RT-QH regime. The relevant e-ph process conserves the LL number, but modifies the in-plane electronic momentum. We note that this phenomenology is fundamentally different from that of magnetophonon oscillations, recently discovered in extra-wide graphene devices36, which rely on resonant inter-LL scattering at T < 200 K. Here, two-phonon scattering within each LL contributes with a conductivity pre-factor σ0 = σN(T/300 K)(B/10 T)1/2, which depends both on temperature and magnetic field (in contrast to the constant pre-factor commonly assumed in QH studies). In the ν = 2 state, the predominant contribution to the σN terms comes from the N = 0 LL 24. Strikingly, the resulting activated behaviour, not including any free parameter, is well approximated by our devices, while the reference data from graphene on SiO2 follow the long-range disorder limit. The qualitative agreement between theoretical calculations and experimental data, together with the contrasting behaviour with respect to previous reports20, indicate that graphene/hBN heterostructures support an e-ph-dominated transport in the RT-QH regime. Arrhenius-type fits to the conductivity37, shown in Fig.We then employ the sample temperature as an experimental knob to control the excitation of both phonons see Fig.  and bulkT curves are acquired for D4 due to experimental limitations) with a generalized relation . This term is intended to account for the effect of residual disorder, and it is the only free parameter in the fits. In Fig. ρD for the three samples at different magnetic fields, as a function of the n* parameter (averaged between the electron and hole-side). The linear ρD(n*) behaviour observed here , is also the one to show a Drude mobility comparable to the zero-field e-ph limit5. Taking into account the sample-dependent correction due to residual disorder, in SI , suggesting a temperature-driven crossover between regimes dominated by either disorder or e-ph interaction . While it is not surprising that the e-ph limit works as a lower bound to the activated resistivity of real samples, the non-universality  of the disorder contribution deserves particular attention in future theoretical treatments of the RT-QH in graphene.Despite the presence of long-range potentials Fig. , our dat SI Fig.  we proceSI Figs.  and S8 w215. In both cases, ripples induce inhomogeneity of electron density with electron and hole puddles in the vicinity of the CNP39. In particular, for the case of graphene on SiO2 the amplitude of induced inhomogeneity of charge-carrier density is estimated as 3 × 1011 cm–239, in agreement with the above cited experimental values of n*. This makes the system strongly disordered, and any intrinsic scattering mechanisms become irrelevant. Oppositely, the hBN substrate is atomically flat1 and at the same time suppresses intrinsic ripples which increases the RT carrier mobility by an order of magnitude and makes intrinsic scattering mechanisms dominant15. Indeed, experimentally measured n* for our samples is an order-of-magnitude smaller than what is supposed to be induced by ripples at RT. This results in an essentially different picture of QH physics at high enough temperatures.The physics of graphene is essentially determined by its deviations from flatness , due to either thermal fluctuations associated to flexural phonons for freely suspended samples or to roughness of substrate like for graphene on SiOIn conclusion, we showed experimental evidence of predominant e-ph scattering in the QH regime. This is realized by uniquely combining strong magnetic fields, high temperatures and hBN-encapsulation of graphene. Although the RT-QH in graphene has long been known, we showed that mitigation of disorder via van der Waals engineering provides novel insights on the transport mechanisms in this phenomenon.5, starting from micromechanically exfoliated graphene flakes previously identified by optical and Raman microscopy. Sample D4 is obtained by CVD growth on Cu foil and direct hBN-mediated pick-up after controlled decoupling via Cu surface oxidation31. All the devices are fabricated making use of electron beam lithography, reactive ion etching and e-beam evaporation of Cr/Au 1D edge contacts5.hBN/graphene/hBN samples D1-3 are assembled using the standard van der Waals dry pick-upρxx and ρxy measurements in four-probe configuration, either under a constant current excitation  or a constant voltage bias . The devices are mounted in a VTI system with low-pressure 4He serving as exchange gas, coupling the samples to a liquid-N2 reservoir. The cryogenic system is accommodated in the access bore of a resistive Bitter magnet at HFML-EMFL, with a maximum field of 33 T.We use standard lock-in acquisition at low frequency (13 Hz), with simultaneous Further information on research design is available in the Nature Portfolio Reporting Summary linked to this article.Supplementary Information


A polarization-insensitive broadband terahertz absorber with a sandwich structure of metal–dielectric-graphene is designed and simulated. The graphene is patterned as an array of graphene square blocks with circular apertures. The results of the simulations and theoretical analysis show that the absorption exceeds  The terahertz frequency band located in the transition region from electronics to photonics in an electromagnetic wave is generally regarded as eristics . In receeristics ,4. There0/21 [Graphene, a single layer of carbon atoms, was the first two-dimensional material discovered  and has  TM mode . The proee space . The abs.165 THz . Althougectively . The proof 62.8% . HoweverIn this study, a polarization-insensitive broadband tunable terahertz absorber is designed and simulated. The absorption acquired exceeds The schematic view of the designed absorber is displayed in The structural parameters of the proposed absorber are listed in In the calculations, graphene was considered a very thin dielectric film with a thickness of  formula :(1)σ, there are two factors for the surface conductivity of graphene. The former originates from interband transition and is represented by the symbol  formula :(2)σg≈σiAccording to Formula (2),  spectra . Based oThe properties of the designed absorber are analyzed with a commercial simulation software named FDTD solutions . S21|2 and 11|2, respectively, where S11|2. Considering the impedance matching principle, when the equivalent input impedance matches the free space impedance, the absorption achieves the maximum yield, and the normalized equivalent input impedance can be described as follows [The absorption can be expressed as  follows :(3)Z(ω)=According to Formula (3), when xP = yP = esonance . When thesonance .The influence of different geometrical parameters on absorption properties are illustrated in The effect of the parameter The influence of the middle dielectric layer with different thicknesses is depicted in Whether the absorber has dynamic adjustability was one of the important criteria to judge its performance. As an excellent two-dimensional material, the conductivity of graphene has proven to be connected with its chemical potential An important index parameter to evaluate the performance of an absorber is to see whether it can always retain good absorption performance under the conditions of different polarization modes, different polarization angles, and different incident angles ,22. The The influence of incident angles was also discussed. The related results are illustrated in Finally, comparisons of our designed absorber to other previously reported absorbers were carried out, and the results are shown in In conclusion, a simple structure of a graphene-based terahertz absorber is designed to achieve high absorption, broadband, and polarization insensitivity. The proposed device consists of a periodical array of graphene square blocks with circular apertures, a polyimide dielectric layer as a spacer, and a gold plate as a substrate. Terahertz absorption is more than


To study the role of ataxia telangiectasia mutated (ATM) in the platelet-derived growth factor (PDGF)-BB-induced proliferation of pulmonary arterial smooth muscle cells (PASMCs) through reactive oxygen species (ROS) formation.2O2). The activation level of ATM and the proliferation level of PASMCs were measured by immunofluorescence staining and Cell Counting Kit-8, respectively. Moreover, NADPH oxidase 2 (NOX2) and intracellular H2O2 were detected under the stimulation of different levels of PDGF-BB by Western blot and dihydroethidium staining.Primary cultures of PASMCs were treated with different concentrations of PDGF-BB or exogenous hydrogen peroxide (HP < 0.05). With the ATM inhibitor, 50 ng/ml of the PDGF-BB group showed further increased proliferative level compared to the 10 ng/ml (P < 0.05). Both the levels of NOX2 and H2O2 showed dose-dependent manners under PDGF-BB stimulation (P < 0.05). ATM could be activated by H2O2 upon a dose-dependent way, except for the 500 μM H2O2 group. Under 200 μM H2O2 stimulation, proliferation level decreased significantly (P < 0.05), while no significant difference was shown with the addition of ATM inhibitor (P > 0.05).Both the control group and 50 ng/ml of the PDGF-BB group showed significantly higher levels of phosphorylation ATM compared to other groups .Our study first established ROS-induced ATM activation in PDGF-BB-stimulated proliferation of PASMCs. Inhibition of ATM had promoted effects on the proliferation of PASMCs under the excessive levels of PDGF-BB and H Pulmonary arterial hypertension (PAH) is a chronic disease, characterized by the narrowing and obstruction of the small pulmonary arteries, which results in increased pulmonary vascular resistance, right heart failure, and probably causes death . AlthougAtaxia telangiectasia mutated (ATM) is a serine/threonine kinase. Together with DNA-dependent protein kinase catalytic subunits (DNA-PKcs) and ATM- and Rad3-related (ATR), these three are members of the phosphatidylinositol-3 kinase-like protein kinase (PIKK) family. When DNA damages occur, these proteins can activate the repair mechanism and suspend the duplication by activating the cell cycle checkpoint , 5. ATM Platelet-derived growth factor (PDGF) can act with PDGF receptor to promote the proliferation of human PASMCs. A clinical trial evaluating the PDGF receptor inhibitor has been carried out for treating PAH . In the 2O2) to stimulate the PASMCs under ATM inhibition to figure out the role of ATM in PASMCs proliferation.Thus, we conduct a PDGF-BB-induced PASMC proliferation system to study the role of ATM through the addition of ATM inhibitor, along with detecting the NADPH/ROS signaling activation under different concentrations of PDGF-BB stimulation. Furthermore, we use different levels of hydrogen peroxide (H2 atmosphere. Primary PASMCs were subcultured to the third generation and readied for the experiments. Anti-α-smooth muscle antibody (SMA) and antiosteopontin (OPN) antibodies were used to confirm the PASMCs . The third generation of PASMCs was treated with PDGF-BB for 24 h, following the starvation for 24 h in DMEM without FBS. The concentrations of PDGF-BB were 2, 10, and 50 ng/ml, while the same volume of PBS was added as the control group. A total of 3 μM of ATM inhibitor was administrated for 30 min prior to PDGF-BB treatment. After 24 h treatment, PASMCs were harvested for the next experiments .2O2 was prepared into 20, 100, 200, and 500 μM with serum-free DMEM. The third generation of PASMCs was cultured in different concentrations of H2O2 for 1 h with or without ATM inhibitor pretreatment, followed by the replacement of the medium to normal DMEM with 10% FBS for another 24 h. Then, PASMCs were harvested for the next experiments . Heriments .staining . The thi2. Absorbance was measured by a microplate reader under 450 nm.Cell Counting Kit-8 (CCK-8) was purchased from the Dojindo . According to the manufacturer's instruction, the third generation of PASMCs was cultured in a 96-well plate. After specific treatments, 10 μl of the CCK-8 solution was added to each well, followed by 2 h incubation at 37°C with a humidified 5% COImmunofluorescence Staining Kit was purchased from Beyotime . The third generation of PASMCs was cultured on the cover glass for a 48-well plate. All the procedures are strictly followed by the manufacturer's instructions. Briefly, cells are fixed and blocked by using the fixing buffer and blocking buffer, respectively. Antiphosphorylated ATM antibody  was used for incubation and detection at 4°C overnight. After removal of the primary antibody, a specific fluorescent enzyme-connected secondary antibody was used for 60 min in a dark chamber. The fluorescent microscope was used to detect the phosphorylated ATM, which submitted the red fluorescence.TM MP Imager . The densitometry values were measured using the FluorChem 8,000 software .Pulmonary artery smooth muscle cells were washed three times with PBS on the ice and lysed by NP40 lysis buffer  for 30 min. Cell lysates were collected and centrifuged at 12,000 g for 5 min at 4°C. The supernatant was kept and determined by BCA Protein Assay Kit . Proteins (50 μg/lane) were added and separated by electrophoresis on 10% polyacrylamide sodium dodecyl sulfate gels, followed by transfer to polyvinylidene fluoride (PVDF) membranes. The membranes were incubated with anti-NOX2 antibody at 4°C overnight and a secondary antibody for 60 min at room temperature. The blots were developed using the enhanced chemiluminescence (ECL) Western Blotting Detection System with a ChemiDocP < 0.05 was considered significantly different.All the data were presented as mean ± SEM. One-way ANOVA followed by the Bonferroni test was used to examine the statistically significant differences between multiple groups. P < 0.05). Further, proliferative level of PASMCs was measured by CCK-8 assay. Without the pretreatment of ATM inhibitor, 2, 10, and 50 ng/ml of groups showed a significant increase in proliferation compared with the control group. There is no significant difference identified between 10 and 50 ng/ml of groups. With the pretreatment of ATM inhibitor, proliferative levels of PASMCs under PDGF-BB treatment were not affected. Interestingly, a slight but significant difference was found between 10 and 50 ng/ml of groups . Our data suggested that PDGF-BB can increase the expression of NOX2 in a dose-dependent manner.Many studies revealed that NOX2 could produce Hulations . Additioons (2O2 . Therefo2O2 level. As shown in 2O2 level increased significantly (P < 0.05). More important, after the pretreatment of DPI, H2O2 level did not elevate after PDGF-BB stimulation (P < 0.05). These data demonstrated that PDGF-BB stimulation can promote the H2O2 accumulation and DPI, NOX2 inhibitor, can abolish this effect, which means that NOX2 took responsibility for the formation of H2O2.To further detect the level and its resource, we treated the primary PASMCs culture with different concentrations of PDGF-BB following 24 h starving. We also set the diphenyleneiodonium (DPI) group, which contained the 30 min pretreatment of DPI followed by 50 ng/ml of PDGF-BB treatment. DHE staining was performed to detect the H2O2 on PASMCs, we incubate the primary PASMCs with extra H2O2 . Proliferation study (CCK-8 assay) revealed interesting results (2O2 could significantly promote the proliferation of PASMCs compared to the control group (P < 0.05). With the stimulation of 200 μM H2O2, proliferation level decreased significantly (P < 0.05). However, with the addition of ATM inhibitor, proliferation level under 200 μM H2O2 did not show a further decrease compared with the control group (P > 0.05).To understand the role of Htra H2O2 . After 2 results . Lower lOur study first brought ATM mechanism into PAH by detecting ATM activation in PDGF-BB-stimulated proliferation of PASMCs. We revealed that the optimal level of PDGF-BB could activate the limited amount of ROS formation, which inhibited the phosphorylation of ATM and promoted the proliferation of PASMCs. However, a high concentration of PDGF-BB could not promote the proliferation of PASMCs, which might be caused by the accumulation of excessive ROS formation. Intriguingly, with the ATM inhibitor, a high level of PDGF-BB showed additional positive effects on the proliferation of PASMCs.Ataxia telangiectasia mutated is first identified in patients with ataxia telangiectasia, characterized by the extreme cellular sensitivity to radiation and a predisposition to cancer . Activatin-vitro PAH model to mimic the proliferation of PASMCs. Under different stimulation levels of PDGF-BB, we found the different activation levels of ATM. Interestingly, the ATM inhibitor could discharge the plateau effect of a high concentration of PDGF-BB and further promote the proliferation of PASMCs under the high level of PDGF-BB. In addition, under the low level of PDGF-BB stimulation, ATM kept inactivated status, while ATM was activated under serum-free conditions. Our study suggested that the functional status of ATM at least partially determines the proliferation of PASMCs with the stimulation of PDGF-BB.Recently, a review article revealed that the proliferation of PASMCs in pulmonary arterial hypertension showed many cancer-like characteristics. PASMCs showed similar patterns compared with the features of cancer cells, including cellular metabolic disorder, self-sufficiency in growth signals, insensitivity to antigrowth signals, limitless replicative potential, sustained angiogenesis, and evading apoptosis . In the 2O2. In our experiments, a lower level of H2O2 (< 200 μM) could promote the proliferation of PASMCs without activation of ATM. However, a higher level of H2O2 had negative effects on the proliferation of PASMCs, which could also activate the ATM. Surprisingly, with the inhibitor of ATM, 200 μM of H2O2 had no longer negative effects on the proliferation of PASMCs.Ataxia telangiectasia mutated is reported to not only respond to the DNA double-strand breaks, but also be activated under oxidative stress . It is r2O2 level under different concentrations of PDGF-BB stimulation. Both the activation level of NOX2 and H2O2 level showed a dose-dependent way of responding to the stimulation of PDGF-BB. Taken together, we suggested that PDGF-BB could induce ROS through NOX2 activation. With the accumulation of excessive ROS, ATM can be activated to call for the cell cycle arrest to stop the proliferation of PASMCs. More importantly, with the ATM inhibitor, a higher proliferation level of PASMCs was shown compared to the same condition without the ATM inhibitor.Many studies demonstrated that dysfunction of mitochondria, activation of NOX family, and uncoupled NOS contribute to the ROS formation in PAH . It is sTo summarize our study, we first established the role of ATM in the PDGF-BB-stimulated proliferation of PASMCs. The generation of ROS from NOX2 was involved in this new pathological mechanism in PAH. Our study might provide a new pharmacological target for the treatment of PAH, which was to restore the ATM function to prevent the pathological proliferation of PASMCs. According to the study in oncology, we hypothesized that the genetic dysfunction of ATM might take responsibility for PAH, which needs further clinical data about patients with PAH to confirm.The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.The animal study was reviewed and approved by the Ethics Review Boards at the Sichuan University.CQ and YZ accomplished most cell studies and biological studies. CQ wrote this manuscript. LX helped cell studies and biological studies. HL designed the study and supervised the whole experiments. All authors contributed to the article and approved the submitted version.This study was supported by the National Scientific Foundation of China (81700311).The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


Development of the Italian clinical practice guidelines on bariatric and metabolic surgery, as well as design and methodological aspects. Background: Obesity and its complications are a growing problem in many countries. Italian Society of Bariatric and Metabolic Surgery for Obesity  developed the first Italian guidelines for the treatment of obesity. Methods: The creation of SICOB Guidelines is based on an extended work made by a panel of 24 members and a coordinator. Grading of Recommendations, Assessment, Development and Evaluations (GRADE) methodology has been used to decide the aims, reference population, and target health professionals. Clinical questions have been created using the PICO  conceptual framework. The definition of questions used the two-step web-based Delphi method, made by repeated rounds of questionnaires and a consensus opinion from the panel. Results: The panel proposed 37 questions. A consensus was immediately reached for 33 (89.2%), with 31 approved, two rejected and three which did not reach an immediate consensus. The further discussion allowed a consensus with one approved and two rejected. Conclusions: The areas covered by the clinical questions included indications of metabolic/bariatric surgery, types of surgery, and surgical management. The choice of a surgical or a non-surgical approach has been debated for the determination of the therapeutic strategy and the correct indications. Obesity and its complications are a growing public health concern in many countries, due an increasing prevalence, a relevant impact on the health of affected individuals and a growing related economic burden . TreatmeThe development of rigorous guidelines is a relevant tool for the improvement of the quality of care, increasing the appropriateness of therapeutic choices. The Italian Society of Bariatric and Metabolic Surgery for Obesity  recognized this need and decided to design and develop the first Italian guidelines, aimed at assisting healthcare professionals in the consideration of the surgical option for the treatment of obesity and related conditions. In the Italian national legal environment , the incPanel members, identified by SICOB in collaboration with other scientific societies All members of the panel and evidence review team compiled a declaration of potential conflicts of interest, which were collectively discussed to determine their relevance. In all cases, the reported conflicts were considered minimal or irrelevant; therefore, all components of the panel and of the evidence review team participated in the elaboration of all recommendations.The GRADE method  was deveThe following step is that of defining a series of clinical questions, using the PICO  conceptual framework . Each reFor each question, the panel defines a number of clinical outcomes, which are potentially relevant for the choice of different clinical options. Each outcome is then rated (from 1 to 9) for its importance; those receiving a rating of 7 or higher are classified as “critical” and represent the basis for the development of the recommendation.For each critical outcome, the evidence review team will perform a systematic review of relevant studies, predefining search strategies and inclusion criteria, and performing meta-analyses whenever possible Further assessments include economic evaluations , organizational impact, equity, acceptability, and feasibility. The final recommendation includes all those elements.The definition of questions was performed using a two-step web-based Delphi method, a structured technique aimed at obtaining, by repeated rounds of questionnaires, a consensus opinion from a panel of experts in areas wherein evidence is scarce or conflicting, and opinion is important .Between June and October 2022, panelists were invited to propose questions with the PICO framework and to express their level of agreement or disagreement on each proposed question using a 5-point Likert scale, scored from 1 to 5 . Results were expressed as a percentage of respondents who scored each item as 1 or 2 (disagreement) or as 3, 4, or 5 (agreement). A positive consensus was reached in case of more than 66% agreement, a negative consensus in case of more than 66% disagreement, consensus was not reached when the sum for disagreement or agreement was below 66% . For the2 requiring bariatric or metabolic surgery. Healthcare systems, infrastructures, human and financial resources across Italian regions will be considered in developing these guidelines. Therefore, they are primarily intended to be applicable in Italy. The present guidelines will be used by healthcare professionals, including surgeons, obesity specialists, general practitioners, nutrition experts, psychologists, endocrinologists/diabetologists, and pediatricians.These guidelines will apply to adolescents (age > 13 years), adults, patients with Body Mass Index (BMI) > 30 kg/mThe panel therefore identified 32 clinical questions, organized into six domains:A.Indication for surgery (11 questions);B.Perioperative work-up/management (9 questions);C.Bariatric procedures (5 questions);D.Endoscopic procedures (1 question);E.Revisional surgery (2 questions);F.Postoperative care (4 questions).The approved questions and their related approved critical outcomes are reported in The evidence review team identified the characteristics of relevant studies for each critical outcome, defining search strategy and study inclusion criteria, which are reported in The areas covered by the clinical questions identified by panelists include indications of metabolic surgery, types of surgery, and pre-, peri- and post-surgical management of obese patients. The focus on indications is not surprising: the choice of a surgical or a non-surgical approach for the treatment of obesity and related metabolic conditions is often debated, posing relevant issues for the determination of appropriateness of the therapeutic strategy. In addition, considering the current legislation on professional liability , a correThe focus on procedures to be applied before, during and after the surgical procedure, is less obvious. Interestingly, the identification of those questions was performed by a panel mainly composed of surgeons, showing a clinical vision much broader than the surgical act per se.Some questions were devoted to the application of surgical procedure for the treatment of obesity-related conditions, such as T2D. The possibility of using surgical techniques to treat T2D and other diseases associated with excess weight, even in patients with mild obesity, or not even properly obese, has been pursued by some authors ,4; promiObese patients seeking treatment have expectations of weight loss. Conversely, health professionals have a greater attention to obesity-associated metabolic abnormalities, such as hyperglycemia, dyslipidemia, etc. The panelist planning the development of these guidelines reached one step further, recognizing the central role of longer-term hard outcomes, such as mortality, incident cardiovascular disease, and malignancies. The availability of sufficient evidence for a reliable assessment of the effects of surgery on those outcomes will be verified in the process of developing these guidelines. Appropriately sized, long-term studies on hard outcomes can be considered a priority for research.The choice of a specific therapeutic strategy should be based on the assessment of the risk-benefit ratio, together with cost-utility analysis. This means that adverse events need to be systematically and carefully studied. In fact, safety outcomes have been included for most clinical questions, concurring to the development of recommendations.Transparency in the development process is one of the main determinants of quality of guidelines ,17,18,19The creation of SICOB Guidelines is based on an extended work. Grading of Recommendations, Assessment, Development and Evaluations (GRADE) methodology has been used to decide aims, reference population, and target health professionals. Clinical questions have been created using PICO  conceptual framework. The GRADE manual recommends the explicit publication of clinical questions, relevant outcomes, and summaries of evidence for each outcome. The search strategy and inclusion criteria for the systematic review and meta-analysis for each outcome has been reported in the present study, allowing for the reproducibility of the whole process.


Frontotemporal dementia (FTD) covers a spectrum of neurodegenerative disorders with various clinical and neuropathological subtypes. The two major pathological proteins accumulating in the brains of FTD patients, depending on their genetic background, are TDP-43 and tau. We aimed to evaluate whether total TDP-43 levels measured from the serum associate with the genotype or clinical phenotype of the FTD patients and whether serum TDP-43 provides prognostic or diagnostic value in the FTD spectrum disorders.The study cohort included 254 participants with a clinical diagnosis of FTD  and 105 cognitively healthy controls. Serum total TDP-43 levels measured with a single-molecule array (Simoa) were compared within the FTD group according to the genotype, clinical phenotype, and predicted neuropathological subtype of the patients. We also evaluated the associations between the TDP-43 levels and disease severity or survival in FTD.B = 0.181, 95%CI = 0.014–0.348, p = 0.034). The lowest TDP-43 levels were observed in the subgroup of FTD patients harboring predicted TDP-43 brain pathology . The low levels in the FTD-TDP group were especially driven by C9orf72 repeat expansion carriers (169.2 pg/mL) and FTD patients with concomitant motoneuron disease , whereas GRN mutation carriers did not show decreased TDP-43 levels (328.6 pg/mL). Serum TDP-43 levels showed no correlation with disease severity nor progression in FTD.Total TDP-43 levels in the serum were significantly lower in the FTD group as compared to the healthy control group (275.3 pg/mL vs. 361.8 pg/mL, C9orf72 repeat expansion or FTD-MND phenotype, both subtypes strongly associated with TDP-43 type B brain pathology. Serum-based measurement of TDP-43 could represent a useful tool in indicating C9orf72 repeat expansion and FTD-MND-related TDP-43 neuropathology for future diagnostics and intervention studies.Our results indicate that the total levels of TDP-43 in the serum are decreased especially in FTD patients with the  C9orf72 (C9-HRE) and mutations in the GRN or MAPT genes  . The Simt-test (or Mann-Whitney U for non-parametric variables) to compare age and neuropsychological data distribution between the groups. Correlations between serum TDP-43 levels and other continuous variables were analyzed with Spearman’s rank correlation test or Pearson’s correlation test (depending on the variable distribution). Due to the non-normally distributed TDP-43 data , natural logarithmic transformation was performed (ln-sTDP-43). Differences in serum TDP-43 levels between the diagnostic groups and between the genetic and predicted neuropathological subgroups were evaluated with a multivariate linear regression model adjusted for age and sex. When evaluating diagnostic accuracy, receiver operating characteristics (ROC) curve analysis was used to calculate the area under the curve (AUC) values . A p-value ≤ 0.05 was considered as statistically significant.Statistical analyses were performed using IBM SPSS Statistic version 25 and GraphPad Prism Software version 5 and version 9. The chi-square analysis was used to compare gender distribution and independent sample Demographics of the study cohort are shown in Table N = 359; r = 0.095, p = 0.075) or separately in the FTD group  but showed a significant correlation in the HC group only . When the effect of gender was considered, males had a trend for slightly higher levels of serum TDP-43, but the age-adjusted gender differences were non-significant in the total study cohort , in the HC group , and in the FTD group .Serum TDP-43 levels showed no significant correlation with age at baseline in the total study cohort  vs. the HC group (N = 105) indicated that the levels were significantly lower in the FTD patients compared to HC  when adjusted for age and gender  compared to the HC group (N = 105)  after similar adjustments (age and gender), whereas the TDP-43 levels did not significantly differ between the FTD-tau group (N = 27) and the HC group (N = 105)   showed lower serum TDP-43 levels compared to the FTD-tau group (N = 27)  when adjusted for age and gender  , while the highest levels were found in PSP patients  . The levels in bvFTD patients , nfvPPA patients , and svPPA patients  were in between these extremes. When compared to the HC group  adjusted for age and sex, statistically significant differences were observed between FTD-MND and HC  and between bvFTD and HC   and HC (N = 105) , while no significant differences were found between the GRN mutation carriers (N = 31) (328.6 pg/mL) vs. HC . Furthermore, as expected, no differences between MAPT mutation carriers (N = 3) (361.6 pg/mL) and HC (361.8 pg/mL)  or non-genetic FTD (N = 170) (291.9 pg/mL) vs. HC  (adjusted for age and sex) were detected. When the genetic FTD patient groups  were independently compared to the non-genetic FTD group, only the difference between C9-HRE and non-genetic FTD was statistically significant  , a statistically significant difference was observed between C9-HRE carriers and HC (area under the curve (AUC) = 0.765, with 72% sensitivity and 75% specificity, cutoff 174 pg/mL) and between FTD-MND and HC . In the ROC analysis between the FTD-TDP and FTD-tau groups, the AUC was 0.689 with 63% sensitivity and 68% specificity (cutoff 267 pg/mL). C9-HRE and the FTD-MND phenotype are associated with TDP type B pathology, whereas GRN mutations are associated with TDP type A pathology [GRN mutation carriers were excluded from the whole FTD-TDP group to generate a more specific “FTD-TDP type B” subgroup and compared to the FTD-tau group, the AUC was 0.860 with 85% sensitivity and 77% specificity (cutoff 173 pg/mL).In receiver operating curve (ROC) analyses, the best diagnostic accuracies of serum TDP-43 levels were observed between athology . When GRrs = 0.017, p = 0.807). The survival time was available for Finnish FTD patients (N = 107). Of these, 47/107 died during the follow-up, and the mean disease duration was 4 years. The serum TDP-43 levels did not associate with survival time after the diagnosis in the total FTD group , in the FTD-TDP subgroup , nor in the C9orf72 repeat expansion carrier group .Finally, we investigated if serum TDP-43 levels showed a correlation with the severity or progression of the disease in FTD patients. The results indicated that the serum TDP-43 levels did not correlate with disease severity when assessed by using the FTD-CDR sum of boxes score , e.g., related to differential release or degradation of different TDP-43 forms. Future improved assays, specifically targeting specific TDP-43 forms will help in clarifying the reason underpinning the observed decrease in the serum TDP-43 levels.Our findings showing decreased, rather than increased, total TDP-43 levels in the serum of FTD patients with suspected TDP-43 pathology are in line with a previous study that assessed both total TDP-43 and pTDP-43 in a small cohort of genetic FTD patients, including ten carriers . The stu amounts . In our C9-HRE genotype and FTD-MND phenotype indicating that mainly C9-HRE and FTD-MND-related TDP-43 pathophysiology (TDP type B pathology in C9-HRE carriers and FTD-MND patients vs. TDP type A pathology in GRN mutation carriers) is reflected to the total TDP-43 serum levels measured with Simoa assay. Our findings are in contrast to a previous study, which reported decreased plasma TDP-43 levels also in the GRN mutation carriers [GRN mutation-carrying patients in the present study as compared to the previous one [GRN patients) in the previous study or the fact that different assay methods were used to detect TDP-43 (ELISA in the previous study vs. ultrasensitive Simoa in the present study).Notably, the lowered levels of total TDP-43 in the FTD-TDP group were strongly driven by the carriers . The undious one  could beC9-HRE as well as GRN mutation carriers have a more pronounced TDP-43 accumulation in their brain and concurrently increased release of pTDP-43 from the degenerating neurons, indicated by the higher pTDP-43 levels in the biofluid samples. Given the previous study reporting an inverse correlation of the levels of pTDP-43 and total TDP-43 [C9-HRE/FTD-ALS related disease. Thus, lower levels of TDP-43 in the biofluids, such as serum, could resemble the behavior of β-amyloid as a biomarker in Alzheimer’s disease (AD) patients. It has been reported that decreased β-amyloid levels in the CSF or blood are a hallmark of increased β-amyloid accumulation and aggregation in AD brain [Lower levels of especially total TDP-43 have also been observed in the lumbar CSF of FTD-TDP patients , a findil TDP-43 , it is pAD brain , 35. SimAD brain , the totAD brain . On the AD brain , and thiC9orf72, GRN, or MAPT as well as patients displaying diverse clinical phenotypes. Moreover, in comparison with some other previous studies, which utilized standard ELISA-based detection of TDP-43, we used here the ultrasensitive Simoa method, which allows the detection of targets with a low abundance. The levels of TDP-43 in none of our cases remained below the detection limit, which has been a substantial issue in the previous studies using other analysis methods. The limitations include the fact that although the genetic subgroups were the largest reported thus far, they still are fairly small when considering optimal statistical power in the subgroup analyses . Another limitation is that we did not have the option to correlate the serum levels of TDP-43 to the levels or accumulation of TDP-43 (or pTDP-43) in the brain of the same patients. These analyses could be done in the future in other cohorts, which contain both biofluid and brain samples from the same individuals. They would be helpful for testing the hypothesis of whether lowered serum levels of TDP-43 reflect a more pronounced brain pathology, similarly to β-amyloid in the AD patients. Furthermore, the measurement of serum TDP-43 in a longitudinal setting might also provide further insight into this idea. It should also be noted that the Simoa TDP-43 assay used here is not specific for the pathological truncated and phosphorylated forms of TDP-43 as it detects also the full-length TDP-43 protein. Although significant differences were found between the groups, the overlap in the TDP-43 levels between several groups was substantial , thus limiting the discriminative power of total TDP-43 levels detected using the present Simoa assay. Moreover, TDP-43 is not specifically expressed only in the central nervous system but is expressed also diversely in peripheral tissues. This might also partially explain the overlap between the groups and the differences between different studies. In the future, the diagnostic potential of TDP-43 measurements could be improved by combining measurements of TDP-43 levels with those of other biomarkers, or by developing specific and sensitive assays against different post-translationally modified TDP-43 protein forms, especially the truncated and phosphorylated forms, which associate with pathological changes in the brain.The main strength of the present study is the large and well-characterized multicenter cohort, which includes genetic patients carrying any of the three major FTD-associated mutations in either C9-HRE and FTD-MND related TDP-43 pathology as compared to healthy controls or patients with suspected tau pathology. This result may aid in the much-needed discovery of reliable biomarkers, which would enable distinguishing the different neuropathological subtypes of the FTD spectrum already in the early disease phases in living patients. The discovery of non-invasive, easily accessible, and reliable biomarkers is an essential step for accurate and timely diagnosis and, ultimately, for the development of specific therapeutic strategies targeting the underlying pathological mechanisms in different subtypes of FTD.Our results demonstrate significantly lower serum total TDP-43 levels especially in the FTD patients with


On the demand of low-cost, lightweight, miniaturized, and integrated optical systems, precision lenslet arrays are widely used. Diamond turning is often used to fabricate lenslet arrays directly or molds that are used to mold lenslet arrays. In this paper, mainly by real-time monitoring position following error for slow tool servo, different fabrication parameters are quantitatively studied and optimized for actual fabrication, then by actual fabrication validation, uniform and high-fidelity surface topography across the actual whole lenslet array is achieved. The evaluated fabrication parameters include sampling strategy, inverse time feed, arc-length, etc. The study provides a quick, effective, and detailed reference for both convex and concave lenslet array cutting parameter selection. At the end, a smooth zonal machining strategy toolpath is demonstrated for fabricating concave lenslet arrays. Micro-lsearched . Alternasearched ,7. The dsearched . AnotherThere are varieties of factors that can affect the final fabricated surface finish, such as cutting parameters, tool paths, temperature, cutting fluids, external vibration, and the vibration between the diamond tool and workpiece ,13,14,15To further improve fabricated lenslet array surface topography, this paper, by monitoring position following error, quantitatively studies the impact of sampling strategy, inverse time feed, sampling arc length, fabrication efficiency, and convex and concave lenslet configuration difference. Furthermore, using position following error mitigation methodology as guidance, actual lenslet arrays are fabricated and the improvement in surface topography at the outer region and uniformity across the whole array are verified. At the end, a smooth zonal machining toolpath methodology is introduced, and excellent surface form accuracy for both center and outer region concave lenslets is demonstrated.Here, the study’s geometrical feature is a lenslet array. It comes with two configurations: convex and concave, as shown in To generate the tool path for a designed lenslet array surface, considering the diamond turning conventional spiral tool path, we first generated a spiral curve on a flat surface, and then projected the spiral curve to the designed lenslet array surface. After that, taking the tool radius and rake angle into account, the tool path was generated by implementing cylindrical-coordinate based tool compensation . In thisTo study how well the lenslet can be fabricated, Nanotech 350FG was utilized to fabricate a 14 mm outer-diameter PMMA convex lenslet array, in which each lenslet had a radius of 6.3 mm and a clear aperture 0.35 mm × 0.35 mm. In the first study, a 0.25° constant-angle sampling strategy was applied, corresponding to 1440 points in one rotation cycle. In addition, an inverse time feed of 0.001 s was used. After the fabrication, the sample was measured with a Zygo NewView 8300 white light interferometer, with the measured result shown in To minimize the deterioration and determine the underlying root cause, we introduced PMAC (Programmable Multi-Axis Controller) to capture the real-time motion data, including command position, actual position, their associated acquisition time, etc., so that we could go further into analyzing and understanding the fabrication process. The position following error later discussed in this paper is the difference between the command and actual position.By using PMAC, real-time process data were acquired. Now, knowing the lenslet surface quality deteriorates from center to edge and that the center maintains fidelity to the actual design very well, the whole lenslet array uniformity can be identified if an indicator of outer-region lenslet surface topography is identified. As mentioned previously, the position following error represents local discrepancy very well, which makes it a potential candidate for the indicator. To check it, using the same methodology used in Although it is a small angle for the 0.25° angle cutting condition, it still exceeds the 30 µm arc length for two adjacent points at the edge of the 14 mm outer-diameter lenslet array, which is a large stroke length considering it is a freeform surface with complex local features. This may lead to the surface feature not being sufficiently sampled. In addition, between two adjacent points, the machine performs linear interpolation and a potential desired curve motion is simplified as a straight line, which is called the linearization error, the impact of which has been studied . HoweverWith the overshoot phenomenon in To characterize the inverse time feed more carefully, a further study was conducted. All other parameters remained the same, but only one variable—inverse time feed—was tested, and 0.001 s, 0.002 s, 0.003 s, 0.004 s 0.005 s, and 0.006 s were chosen. For each inverse time feed, the position following error for at least one complete spindle rotation cycle was gathered, and then all peak values demonstrated in Alternative to directly controlling the STS inverse time feed for each step, varying two adjacent arc lengths is an indirect method to alter the command frequency. Therefore, from a position following error perspective, a systematical study for arc-length impact was conducted.Obviously, any arbitrary arc length can be picked, but a small arc length means more stroke step numbers for the same total trajectory. Then, in a practical fabrication environment, a tradeoff needs to be carried out with the goal of achieving a reasonable surface quality for task-specific applications within a reasonable amount of time. To quantitatively understand the role that constant-arc plays in the position following error mitigation process, a study was carried out. In the study, all other parameters remained constant, with only one variable—different arc length—being selected, with representative ones across the spectrum: 0.625 µm, 1.25 µm, 2.5 µm, 5 µm, 10 µm, and 15 µm. For each arc length, similar to Naturally, the combined effect of the STS response time and constant-arc was studied. With the results of the position following error and machining efficiency demonstrated in So far, In addition to the sample shown in To associate the previous tested position following error with actual fabricated lenslet topography, the outer regions of six cases of the above-fabricated lenslet arrays were characterized, and specifically, the fifth-position lenslet, as shown in For the constant-arc, demonstrated in The surface error associated with the convex or concave configuration can be fully explained from a comparison of surface shape in To further investigate the uniformity of lenslet array surface topography from the center region to the outer region, for the six cases of the above fabricated lenslet arrays, the Sq (root-mean-square surface roughness) and Sa  of five lenslets was plotted in All of the study in In this paper, using real-time monitoring slow-tool servo position following error, different fabrication parameters were quantitatively studied and optimized, uniform and high-fidelity surface topography across the actual whole lenslet array was achieved and validated by actual fabricated results. Specifically, through PMAC real-time monitoring position following error at the lenslet array outer region, this paper quantitatively studied the impact of different sampling strategies, inverse time feed and arc-length, along with their associated total machining time consumption for STS. It provides a quick, effective, and detailed reference for both convex and concave lenslet array cutting parameter selection. In the end, a zonal machining strategy was demonstrated, and uniform and high-fidelity surface topography across the whole lenslet array was also achieved.