This paper aims to analyse the state-of-the-art of graphene-based materials and devices designed for use in space. The goal is to summarise emerging research studies, contextualise promising findings, and discuss underway strategies to address some specific space-related problems. To complete our overview of graphene-based technology and address the relevance of graphene in the wide scenario of the space economy, we also provide an analysis of worldwide patents and the scientific literature for aerospace applications in the period 2010–2021. We analysed global trends, country distributions, top assignees, and funding sponsors, evidencing a general increase for the period considered. These indicators, integrated with market information, provide a clear evaluation of the related technology trends and readiness levels. It is certainly not surprising that a material such as graphene has found, and is increasingly finding, wide application in space. Indeed, graphene is 200 times stronger and 100 times more tear-resistant than steel. Moreover, it is the world’s best conductor of electricity and heat, it is characterized by flexibility, transparency, stability, and impermeability, and it has the highest melting point of any material in vacuum. All these features optimally match the needs of current and forecasted space missions, since the latter require materials that are able to withstand extreme conditions of heat, radiation, and impact without losing their functional integrity [The materials employed in the components and structures of a space mission experience strong stresses during the pre-launch ground activities of qualification and testing. During the lift-off and launch phases, the materials are subject to strong vibrations, shock waves, changes in gravitational forces, and high thermal gradients. When in orbit, the materials face adverse effects due to the space vacuum, cosmic radiations, solar wind, atomic oxygen, plasma charging, micrometeoroids, and space debris. Materials of a spacecraft in orbit around the Earth are exposed to temperatures in the −180 °C/+180 °C range, those close to other planets are exposed to temperatures as low as −200 °C, and those in the vicinity of the Sun are exposed to temperatures higher than 520 °C. The re-entry from space missions exposes the materials to overheating. Under the action of so many adverse processes, most conventional materials undergo a degradation of their structural and functional properties. Here, the new, leading, exciting artificial material graphene plays a relevant role: since its discovery, it has demonstrated huge capability in solving many of the problems arising in space-related applications.What is generally unnoticed is that either astronomical observations of interstellar dust and planetary atmospheres, or the analysis of comet, asteroid, and meteorite matter, have revealed that this artificial high-tech material is a naturally-formed nanostructure , represe2 configurations, which resulted either in crystalline graphite or in the building blocks of amorphous sp2 carbons, the so-called black carbon [Simulation experiments have provided evidence of the chemical steps and physical pathways leading to the formation of two-dimensional sp2-carbon nanostructures in deep space. The current hypothesis is that graphenic structural units originated from a protosolar carbon reservoir and were synthesized in a high-temperature zone near the proto-Sun and during the solar system’s earliest era ,6. Most k carbon ,8.2/V s) and thermal conductivity (5.3 kW/m K). Unfortunately, such outstanding properties are exhibited only by high-quality single-layer graphene, a miracle material that, up to now, can be produced only in small amounts by using sophisticated methods [The studies by Novoselov et al.  highligh methods .The unusual combination of mechanical, electrical, electronic, optical, and thermal properties of graphene have led to a focus on great efforts in the set-up of techniques for the mass-production of graphene-like nanostructures that are able to offer solutions to a variety of technological problems ,12. PresEven if characterised by lower performance with respect to conventional graphene, the achievements obtained using this graphene for the engineering of advanced materials, structures, and devices now make these nanomaterials a key player in all the space-related sectors.Therefore, whereas graphene detected in interstellar media and ancient astromaterials is used to re-tell the story of the universe, artificial honeycomb carbon structures (graphene-based solids) go to space as cutting-edge materials that are able to enhance the mechanical, chemical, electrical, and optical properties of the components and structures in spacecrafts and satellites. In space domains, such multifunctional lightweight graphene materials (hereinafter referred to as graphene) have a transversal impact across all the sectors, from the processing of materials to the assembly of ground equipment and the launcher industry, and from satellite manufacturing/services to space science and exploration, just to name a few.However, advanced and highly competitive coatings, structural components, or functional systems rarely make use of graphene on their own. For space applications, graphene is used mainly in combination with metals or polymers, giving rise to nanocomposites where the graphene insertion greatly influences the features of the host matrix. The engineering of graphene-based composites and the design of materials with the on-demand combination of tailored properties are therefore a primary goal of today’s space-related technologies.The focus of this paper is to describe the state-of-art of graphene-based composites and to briefly illustrate some interesting examples of how graphene is applied to overcome challenges posed in space, dwelling on certain key themes that require additional research and drawing attention to some unexpected and surprising applications. Moreover, the issue of the space-related economy  is also The aircraft and spacecraft industries rely heavily on aluminium, magnesium, and titanium alloys due to their light weight, high mechanical properties, low cost, and also reasonably good temperature resistance . GraphenThe wide range of different uses envisaged for different environments needs the fine tuning of highly specific, and sometimes rather complex, materials. An example is given by graphene layers, functionalised with carboxylic and hydroxyl groups, wrapping the silicon carbide (SiC) particles used as the filler in microstructured aluminium. These nano composites showed an increase in storage modulus and ultimate tensile strength by a factor of ~2.1 and ~3.4, respectively, compared to pure aluminium .The improvement of nanocomposite mechanical features is accompanied by the improvement of thermal properties, such as thermal conductivity, specific heat capacity, and the thermal expansion coefficient. These effects can be of great value, as can be appreciated from the results obtained in the case of graphene–magnesium nanocomposites, a material much lighter than any existing alloy used by the aerospace industry .However, the achievement of outstanding thermo-mechanical results is not an easy task to obtain just by adding graphene to a metal because the insertion of a nanofiller produces structural modifications in the host metal lattice. To obtain a material with the required properties, a strict control for the material structure is needed at the nanoscale level. An example of how to manage this issue can be found in . In thisExperimental nanostructural studies on graphene-Al nanocomposites for aerospace applications have confirmed the Molecular Dynamics (MD) simulations . The enhThe strengthening of the composite material is achieved by the transfer of the load from the matrix to the graphene flakes, which, in this view, would act also as a load-bearing component and not just like a control for the dislocation movements. The effective transfer of the strain to the filler enables the processing of Al/graphene powders via the traditional metallurgical routes. The structural components of the external fuel tanks of launch vehicles are fabricated using a microwave powder-sintering method followed by hot extrusion .Overall, the most recent research has underlined how the thermo-mechanical properties of graphene-metal materials are driven by their structural features at the nanoscale level, confirming how nanocomposites for aerospace applications must be accurately designed.Graphene-based polymer nanocomposites are currently at the forefront of materials used for aerospace structural components. The obvious mechanical advantages that result from the ingenious coupling of graphene with a suitable polymer have indeed made such light-weight and easily manufactured nanocomposites a standard in the engineering of aerospace structural components. However, the many outstanding properties that graphene transfers to the host polymer have also been exploited in other applications, often still at the research stage, such as those in thermal management or space propulsion .The large number of polymers under consideration and the many actual or planned space applications need to put into play all the techniques/protocols settled until now to produce, engineer, and process multifunctional nanocomposites . One of In this context, the challenge is to develop manufacturing techniques and to envisage other hitherto unexplored approaches that are able to assure the specific performance required in uses that include, among others, sensors, antistatic coatings, and electromagnetic interference shields .A further space-specific application of graphene-based nanocomposites is the fabrication of ablative coatings in the hyper-thermal environments experienced by space vehicles and rocket motors. Ablation tests demonstrated that the addition of graphene to elastomeric matrices greatly reduces the temperature rise at the back face of the coatings, highlighting an increase in thermal stability and in the heat absorbance capability of the nanocomposites with the increasing of the filler-matrix ratio . The maiApproaches based on multi-scale methods are also widely employed in the case of graphene/polymer nanocomposites to model the structure of the materials and the architecture of the systems following the requirements of the specific spatial uses . To desiTo deeply understand the graphene-induced effects on the mechanical properties of polymers used for aerospace structures, in particular for sandwich panels, a major topic is the precise measurement of graphene-polymer interfacial strength. An interesting approach used to quantify such interactions is illustrated in . Here, tIt is noteworthy to report that a vehicle made with graphene-polymer composites has been assembled by Orbex, the UK-based private, low cost orbital launch services company . The twoFrom the beginning of the “graphene era”, thermal management systems used in space have greatly relied on the use of the material. Even if, up to now, the value of thermal conductivity foreseen by Novoselov et al.  has not In the recent years, the European Space Agency (ESA) have started to test graphene for the cooling of loop heat pipes in a low-gravity environment . The mai3 m  and 106 m (the outer limits of the atmosphere below the van Allen radiation belts). Here, the satellites are exposed to solar radiations, Earth albedo, and Earth infrared radiations, effects that altogether contribute to a remarkable temperature increase. Temperature variations are currently kept under control in large satellites by loop heat pipes (active systems) and also by the passive protection offered by insulating paints or multilayer insulation blankets.The miniaturisation of the thermal management systems that can be achieved using graphene materials is of utmost importance for small satellites, which are contributing more and more to the advancement of scientific explorations and to the reduction of mission costs. The altitude reached by a small satellite in a low Earth orbit is between 15 × 10However, for small satellites, efficient thermal dissipation technologies are still under development. A new concept for heat dissipation in these systems is to adapt the loop heat pipes proposed for larger satellites, adding graphene nanoparticles to the conventional heat transfer fluids. Increased thermal performance induced in fluids by the graphene phase resulted in a continuous heat dissipation of 75 W, enabling the retention of the 6 U CubeSat payload within a suitable temperature range . FurtherFor all spacecrafts, rockets, and satellite components, corrosion is a very big challenge to deal with. Prolonged exposure to a variety of adverse agents in the whole of space, from near-Earth to deep space, produces material loss in the surfaces. This effect is especially evident in aluminium alloys, and the coating by anticorrosion layers is therefore a pivotal subject of applied research. In this context, GO-based materials inserted in a polymeric matrix were demonstrated to improve the corrosion resistance of the applied layers , likely The exposure to erosive solar wind is an issue that hampers the use of conventional materials in the equipment employed in outer space. This problem arose particularly when the construction of a probe microscope-space satellite was planned. For such a high-precision device characterised by a reduced weight (not exceeding a few kilograms) and by the ability to work in vacuum, the need to counteract erosion was handled by using graphene multi-layered structures prepared by the thermomechanical compression of several sheets of CVD-produced single-layer graphene. This material has been plasma-treated in-laboratory under conditions imitating solar wind. The experiments confirmed that such light multi-layered structures are effective shields for equipment protection and also provide promising structural material for solar sailing .In the field of advanced optoelectronic systems and devices, graphene is now a rather ubiquitous material. Several reviews, to which the reader can refer in ,39,40, iGraphene sensors highly sensitive to THz frequencies that are able to detect polarisation and moreover to be adjusted electronically have been planned to be used in Sun THZ. This is a telescope designed to detect flares and phenomena of solar explosions that occur on the Sun’s surface, and cause high levels of radiation in outer space. Sun THz is an enhanced version of Solar-T, a double photometric telescope launched in 2016 by NASA in Antarctica in a stratospheric balloon. The Solar-T telescope captured, for the first time, the energy emitted by solar flares at two frequencies in the 3–7 THz range, corresponding to a segment of far infrared radiation. The new Sun THz telescope will be sent to the International Space Station (ISS), where it will remain, to measure the full spectrum of solar flares, which is from 0.2 THz to 15 THz. The unconventional detection of such frequencies, which can be measured only from space, together with the foreseen prolonged exposition of the telescope to high radiation levels, make it necessary to use materials with outstanding photonic properties and high radiation resistance. The graphene-based sensors for the Sun THz telescope are being presently developed in the frame of an international Brazil-Russia-UK collaboration .Other types of sensors that take advantage of the use of graphene are bolometers, devices widely used in sub-millimetre astronomy to analyse radiations through the measurement of radiated heat. The small heat capacity, the weak electron-phonon coupling, and the low electrical resistance of graphene are intrinsic properties that can strongly improve the performance of such detectors. Du et al.  analysedHowever, it must be noted that photonic devices, such as bolometers or saturable absorbers in ultra-high bandwidth detectors, need the manufacturing of large area graphene, either as a single layer or multi-layered. To that end, scientists at NASA developed, in 2019, a synthesis process that was able to produce graphene sheets that were suitable for the assembling of such photonic devices .In addition, sensors based on the Hall effect are widely used in space. The Hall effect sensors are key electronic components present in a variety of devices that are used for proximity sensing, positioning, speed detection, and current measurements. The devices assembled with conventional semiconductors must be encapsulated in heavy-radiation-resistant packages to avoid damages and failures induced by neutron radiation. Tests performed in the UK’s National Physical Laboratory proved that graphene Hall sensors can withstand exposures to neutron doses as high as 241 mSv/h, about 30,000 times the neutron dose typically experienced in the International Space Station. Moreover, the replacement of silicon with graphene increases the sensitivity of these electronic devices, which require only few pW of power and are extremely lightweight. These valuable features make graphene Hall sensors well-suited for employment in satellites and spacecrafts .The solar-photon sails, commonly called solar sails, are innovative propulsion systems proposed to drive flights and the orbital manoeuvres of spacecrafts in deep space. A solar-photon sail utilises the pressure of solar photons to drive an object in space without using fuel or gases. The propulsion is given by the force that originates from light reflecting off a surface or being absorbed by it, and from the consequent pushing of the surface itself away from the light source. The concept of a solar sail is a potential option for driving long-duration extrasolar and interstellar exploration/colonisation missions, but the application requires a thin, light weighted, reflective, temperature tolerant, and space-environment-resistant sail. The technology of large sails made of polyimide and mylar coated with a metallic reflective thin layer was firstly tested in the IKAROS mission launched in 2010 by the Japanese Aerospace Exploration Agency (JAXA) and, after that, redesigned considering the use of graphene ,47,48.In , a low-wThe sail system of graphene micromembranes supported by copper grids was tested under microgravity and vacuum conditions by measuring the displacement induced by laser irradiations of a 3 mm scale model. Lasers with optical DC powers of 100, 500, and 1000 mW produced forces in the 8–248 nN range, and demonstrated the feasibility of the light-induced acceleration of the 2D sails.2 acceleration of the sail. Solar sails based on graphene are extremely promising forms of spacecraft propulsion because these devices have few moving parts, use no propellent, and have long operational lifetimes.Currently, the visionary technology of solar sails made by free-floating graphene membranes has also been explored by China , by the However, a really innovative, cutting-edge graphene-based propulsion can be provided by a mechanism that is different from that of the photon-reflection, exploiting a new concept first put forward in a 2015 paper . The autWireless communication systems in space need multiband operations and, at the same time, an optimal method for the utilisation of onboard components. In this context, many studies have focused on the fabrication of reconfigurable multiband antennas. However, there are other constraints on the actual applications of antennas in space, such as their low power, small size, and minimal cost. It has been demonstrated that graphene-based conductive inks offer the feasible realisation of antennas characterised by frequency reconfigurability and also by a significant reduction in cost, size, and maintenance. Indeed, the printing of this composite material enables the fabrication of textile-based, highly effective microstrip antennas capable of switching between the S-band  and C-band  .More recently, Cherevko et al.  fabricatAmong graphene’s outstanding properties, the effective propagation of surface plasmon polariton allows graphene-based antennas to resonate at higher frequencies with respect to a metal patch antenna of the same size. The dual graphene patch antenna proposed in  enables Moreover, in small satellites like SmallSat and CubeSat, there is very little space to insert antennas as well as the solar panels providing energy, and the integration of the two devices in a single compact unit is a challenging task. An innovative approach to overcome this difficulty was proposed by Ram et al., who fabricated a micro-strip patch antenna integrated with a solar panel by screen printing a graphene-based nanomaterial . This te2/Vs and an electrical resistivity of about 10−6 Ω·cm in the THz band. Such properties result in a loss lower than that of conventional metals. In addition, in graphene, the surface plasmons exhibit lower resonant frequencies than those in metals and extremely small wavelengths, and are tightly confined on the graphene sheet. The excellent physical properties of graphene at THz frequencies have been exploited in a series of graphene-based THz antennas as the reflect array formed by a circularly polarised source and several graphene-based unit-cells were proposed for operation in the THz regime. This design enables the realisation of a high-gain antenna with a large bandwidth and a phase tunability of a wide band (1.4–1.7 THz), making the system suitable for THz communications [Graphene has several advantages over metals also at the THz band. It has a room temperature electron mobility of up to 230,000 cmications .Another exciting use of graphene for space-related applications is in the fabrication of ultrathin flat lenses, a revolutionary technology that, in space, is hampered by the harsh environmental conditions. In this context, it was thought that graphene-based lenses could have better stability and could also maintain outstanding focusing performance under space conditions . Using aThe stability of the graphene lens was tested in experiments simulating low-Earth-orbit space conditions, which include the exposure to extreme heat/cold cycles, strong UV, higher energy radiations, an ultrahigh vacuum, and atomic oxygen . These uElectrical energy storage devices exploiting the good electrochemical features of graphene have been proposed since 2008 , and sevAn interesting example of GSC being specifically designed to be used without a backup of conventional batteries is reported in . Here, GIn the previous paragraphs, we have examined many different applications of graphene-based materials in space. Most of the information provided above was extrapolated from scientific publications, contracts, etc. However, in this paragraph, we would like to lend a different perspective by providing some quantitative indicators of the scientific literature and patents. In fact, we are aware of how the statistical analysis of patent information and its visualization make a powerful and successful methodology for any competitive intelligence activity centred on technology , since tThus, considering the information provided above, we hereinafter analyse the overall worldwide patents and literature to evaluate the technology’s evolution in the period 2010–2021.By using two different dedicated databases, namely Orbit Intelligence  and ElseOn the one hand, patent-based indicators are extremely useful for comparing and monitoring trends in the technology output of different countries; here, this data is complemented with the scientific literature indicators to study empirical and theoretical works and capture what is known on the topics above. On the other hand, scientific literature represents the main source for communicating and disseminating the results of scientific research and, as such, it represents the record of the collective achievements of the scientific community over time.investment and scientific literature trends;country distributions of patents and literature;International Classification Classes (IPC4);top applicants by legal state;top affiliations;dependency of applicants by citation.In the patent analysis hereinafter presented, the data was analysed using the Orbit Intelligence Patent Database tool by Questel with the aim of extracting information from the patents’ titles, abstracts, claims, descriptions, and concepts to identify, among others:Insofar as the scientific literature is concerned, the following paragraph shows results obtained through Elsevier’s Scopus tool with the aim of extracting information from the titles, abstracts, and descriptions of scientific articles.This paragraph presents the results obtained from the analysis of patent families  and from the scientific literature published worldwide between 1 January 2010 and 31 December 2021. We focused our analysis on the keyword ‘graphene’ combined with keywords related to human exploration  and long-term permanence . We excluded from our analysis keywords related to the launcher and to propulsion systems since they could be the object of a dedicated review. Our final dataset included 4967 scientific articles and 6531 patent families. In the following paragraphs, we examine the results of this dataset.The graph in An exponentially-growing patent portfolio indicates that the applicants are in the phase of rapidly constructing their portfolios. A similar increasing trend can also be observed in the scientific publications, confirming the increasing efforts of the scientific community in applying graphene in space. The findings of the above review are fully confirmed by such results, which clearly demonstrate the wide interest in using graphene for space applications.Following such a trend, the stabilisation of patent filings can be expected, which could be motivated by a stabilisation of R&D budgets–which leads to a flow of patent applications that is more or less constant without too much selectivity in applying for patents–and/or the desire to stabilise patent costs, which leads to significant selectivity in the filings and their maintenance.The pie chart in This graph also provides information on the commercial strategies of the applicants in the sectors studied as the national filings are a good indicator of the markets that need to be protected. In addition, many applicants protect the geographical areas where the manufacturing sites of their competitors are located.The following picture  shows thThe following graph  is basedThe description of the IPC4 reported in the picture above is provided in The graph in The following graph  illustraThe outstanding intrinsic properties of graphene make it an extremely suitable candidate as the material of choice to deal with the peculiar characteristics of out-of-Earth environments.The use of graphene and graphene-like nanostructures in space is not limited to the applications briefly reviewed in this paper, but also include radiation shielding, fuel propellants, telecommunications, biomedical technologies, life support systems, and many more. As a whole, a variety of graphene-based products have already found their way into space but, despite great efforts, a number of challenges and untapped opportunities still remain unsolved for such a relevant nanomaterial.The few examples of the forefront graphene-based technologies illustrated in this paper outline that there are still some goals that have not been realised, or at least not completely. The first issue concerns “true” high-performance graphene. To succeed in making graphene operative at its best requires the development of methodologies for the mass production of large-area crystals of one-atom-thick sp2-bonded Carbon. The ultimate performance of the future’s 2D “miracle material” would provide a solution for almost every present and future space-related technology. Several research groups worldwide are already working on this issue and the hope is that they could be only a few “paradigm-shifting” breakthroughs away from the goal.As regards the less-performant graphene-like nanomaterials, leading voices in material science evidence a growing commitment to provide the mass production of few-layers graphene, graphene platelets, graphene quantum dots, reduced graphene oxides, and other graphene-related structures. Near-future research efforts will be aimed towards the large-scale production of structures with homogeneous size, shape, and thickness.In this context, even if the potential toxicity of these amorphous materials has not been established, specific solutions are being introduced to build a safe chain of life for the nanostructures, from their synthesis to their material processing, and from the assembling of systems to their decommissioning.Overall, a series of R&D activities related to graphene applications in space domains are still to be explored, and this accounts for the impressive growth of research activities being presently dedicated to this strategic sector, a trend clearly evidenced by our analysis of patents and the scientific literature.On this basis, graphene is expected to help in reaching very soon the technological levels needed to increase the exploration of the solar system and beyond, and to establish and maintain sites on the Moon, Mars, and other planetary bodies. In order to make such ambitious endeavours feasible, not only is the rapid development of graphene-based technologies needed, but so is the additional support of the related space economy, which can be obtained, in particular, by stimulating not only governments and public industries, but also by promoting private companies’ and investors’ involvement in this sector.


We measured CSF concentrations of TDP-43 in 194 urban residents, including 92 MMC children aged 10.2 ± 4.7 y exposed to PM2.5 levels above the USEPA annual standard and to high UFPM and 26 low pollution controls (11.5 ± 4.4 y); 43 MMC adults (42.3 ± 15.9 y) and 14 low pollution adult controls (33.1 ± 12.0 y); and 19 amyotrophic lateral sclerosis (ALS) patients (52.4 ± 14.1 y). TDP-43 neuropathology and cisternal CSF data from 20 subjects—15 MMC (41.1 ± 18.9 y) and 5 low pollution controls (46 ± 16.01 y)—were included. CSF TDP-43 exponentially increased with age (p < 0.0001) and it was higher for MMC residents. TDP-43 cisternal CSF levels of 572 ± 208 pg/mL in 6/15 MMC autopsy cases forecasted TDP-43 in the olfactory bulb, medulla and pons, reticular formation and motor nuclei neurons. A 16 y old with TDP-43 cisternal levels of 1030 pg/mL exhibited TDP-43 pathology and all 15 MMC autopsy cases exhibited AD and PD hallmarks. Overlapping TDP-43, AD and PD pathologies start in childhood in urbanites with high exposures to PM2.5 and UFPM. Early, sustained exposures to PM air pollution represent a high risk for developing brains and MMC UFPM emissions sources ought to be clearly identified, regulated, monitored and controlled. Prevention of deadly neurologic diseases associated with air pollution ought to be a public health priority and preventive medicine is key.Environmental exposures to fine particulate matter (PM Anthropogenic UFPM are primarily generated via combustion  and subsequent processes of particle nucleation, coagulation and vapor condensation, while NPs are frequently referred to as engineered or manufactured because they are designed and generated for a particular purpose; e.g., medical [Neurodegenerative disorders with complex environmental and genetic pathogenesis start decades before clinical symptomatology is present ,2,3. Quaase (PD) ,9,10,11.ase (PD) ,13,14,15ase (PD) ,21,22,23 medical . Anthrop medical ,27,28,29p = 0.005 and 0.02, respectively) and the fact that non-P-Tau cases showed significantly faster increases in MMC residents versus controls (p = 0.005) [We have previously shown that cerebrospinal fluid (CSF) concentrations of cytokines and chemokines, cellular prion protein (PrPc), total tau (T-tau), tau phosphorylated at threonine 181 (P-Tau), amyloid Aβ1–42, α-synuclein (t-α-syn and d-α-synuclein), brain-derived neurotrophic factor (BDNF), insulin and leptin can be used to distinguish MMC children from low pollution controls ,31,32,33The overlap of several aberrant CSF proteins in children and young MMC adults, including hyperphosphorylated tau, beta amyloid, alpha synuclein and TDP 43 ,2,4, drononlinearly increasing protein concentrations between ventricular and lumbar CSF are fitting to a Gaussian error function, the differential of the nonlinear concentration distribution function between blood and CSF” [Two research groups were critical in defining the relationship and the interpretation of protein concentrations in cisternal versus lumbar CSF; the work by Reiber ,37 and band CSF”  and thatand CSF” .TDP-43 nuclear depletion and aggregation are hallmarks of ALS and frontotemporal dementia (FTD) ,40,41,42In sum, the purpose of the present study was to assess, in MMC versus lower pollution age-matched subjects, the impact of lifetime exposures to highly polluted environments on CSF TDP-43 burden. Our results identify lumbar CSF TDP-43 increasing exponentially with age in young urbanites with high exposures to PM pollution and TDP-43 cisternal CSF levels of 572 ± 208 pg/mL forecasting TDP-43 pathology in young MMC residents.There is a strong association between TAR DNA-binding protein 43, frontotemporal lobar degeneration (FTLD) and amyotrophic lateral sclerosis (ALS) ,51,52; t2.5) and O3 for the last three decades [2.5 concentrations, averaged over 3 years, for representative MMC monitoring stations in the period between 1990 to April 2020 and their comparison with PM2.5 from the US EPA NAAQS.MMC residents have been chronically exposed to significant concentrations of fine particulate matter  [−3. Given that catalytic converters in cars and unleaded gasoline were not enforced in Mexico until the year 2000, MMC CO and PM2.5 levels before 2000 were among the highest levels of criteria pollutants registered in North America [−3 and, given that the PNC trend decreased to the overall average of 44,000 cm−3 after 2003, exposures of MMC residents reached the average PNC for 40 urban areas across Asia, North America, Europe and Australia precisely after 2003 [UFPM and NPs have a very low mass compared with larger diameter particles; therefore, the PM fraction <100 nm in MMC was evaluated through measurements of particle number concentration (PNC) ,61,62,63issions) . The est America . MMC rester 2003 —commerciter 2003 —residentter 2003 —commerci2, and it lies in an elevated basin 7400 feet above sea level. MMC has nearly 22 million inhabitants, over 50,000 industries and over 5 million vehicles consuming more than 50 million liters of petroleum fuels per day. In this megacity, MMC motor vehicles release abundant amounts of primary PM2.5, elemental carbon, particle-bound polycyclic aromatic hydrocarbons, carbon monoxide, nitrogen oxides and a wide range of air toxins and other toxics, including formaldehyde, acetaldehyde, benzene, toluene and xylenes [0.1 emitters [MMC is an example of uncontrolled urban growth and environmental pollution ,62,63,64 xylenes ,58,59,64 xylenes . In addiemitters .3−) and particles with lipopolysaccharides (PM-LPS), while northern children are exposed to higher concentrations of volatile organic compounds (VOCs) and PM2.5 and its constituents: organic and elemental carbon, including polycyclic aromatic hydrocarbons, secondary inorganic aerosols  and metals  [2.5 [In this study, children and adult cohorts included residents in MMC, while subjects from small control cities represented the typical provincial areas where air pollution emissions are minimal. MMC northern industrialized and southern residential zones were represented in our samples. Southern MMC children are exposed to significant concentrations of ozone, secondary tracers (NOanadium) ,56,62,64anadium) ,64. ThesThis prospective study was approved by the review boards and ethics committees at the Universidad del Valle de Mexico, on the 18 November 2020, and the University of Montana, IRB-206R-09, on the 8 December 2016, and IRB 185-20, on the 23 November 2020.Normal CSF samples were selected from two cohorts admitted for investigation of neurological involvement in the context of a hematological, neoplastic or infectious brain processes: (i) children admitted to the hospital from a clean air city or MMC, with a work-up diagnosis of acute lymphoblastic leukemia (ALL) entering a clinical protocol that included a spinal tap, and (ii) young and older adults admitted to the hospital for a work-up that required a spinal tap with varied diagnoses, including potential neoplastic and infectious CNS involvement. The cohort of young and older adults also included permanent residents in clean environments and lifetime residents in highly polluted MMC. The normal CSF samples studied were destined to be destroyed after the diagnosis of normal CSF in the laboratory. We also examined 19 CSF ALS cases from Dartmouth-Hitchcock Medical Center Cerebral Spinal Fluid Bank for research IRB #29104 and 5 Mexican ALS cases under the Universidad del Valle de Mexico 18 November 2020 IRB.The autopsy cases with cerebello-medullary cisternal tap included 15 MMC subjects and 5 low pollution control cases; all had complete forensic autopsies, including full neuropathological examination. These autopsies were performed between 2004 and 2008 under a Consejo de la Judicatura del Distrito Federal permit (14571/2003).3. All CSF samples in this study were read as normal. We performed the hTDP43 total ELISA  according to the instructions for use. This ELISA uses two monoclonal antibodies directed at amino acids 79–91 and 259–271.Spinal tap was performed on the left lateral decubitus from the intervertebral spaces L3-S1 using a standard 22 spinal needle. Spinal taps were performed between 8 and 10 am. CSF was collected dripping in free air in 1 mL aliquot into Nalge Nunc polypropylene CryoTubes. Lumbar puncture samples were collected during non-traumatic, non-complicated procedures. CSF samples were examined immediately to determine haematological, oncological or infectious involvement and then stored at −80 °C and kept frozen until the current analysis. CSF pleocytosis was defined as CSF white blood cell (WBC) counts of ≥7 cells per mmThis work includes CSF data from a pediatric cohort: 92 children from MMC  and 26 low pollution control children . The selected children had no previous oncologic and/or hematologic CNS or systemic treatments and their CSF samples were read as normal, with CNS involvement being ruled out at the time of their hospitalization. Children’s clinical inclusion criteria were negative known smoking history and environmental tobacco exposure, lifelong residency in MMC or the control city, residency within a radius of 2.5 miles of one of the representative city monitoring stations, full-term birth and unremarkable clinical histories prior to their admission to the hospital. We specifically excluded children with a history of active participation in team sports with high incidences of head trauma, including soccer. Mothers had unremarkable, full-term pregnancies with uncomplicated vaginal deliveries and took no illicit drugs, including alcohol and tobacco. These children had a history of breast feeding for a minimum of 6 months and were introduced to solid foods after the age of 4 months. Participants were from middle class families, living in single-family homes with no indoor pets, used LP gas for cooking and kitchens were separated from the living and sleeping areas. Low and high pollution-exposed children were matched by age, gender and socioeconomic status.We had 19 ALS cases , of which 14 were from NH and 5 from MMC; 43 normal MMC CSF samples ; and 14 samples from residents in low pollution cities (9M/5F average age 33.1 ± 12.0 y).SD = 17.9, age range 16 to 83 y) were examined: 15 MMC male residents, average age 41.13 ± 18.9 y, and 5 controls . The inclusion criteria for this cohort included lifelong residency in MMC or the control cities and a cause of death—i.e., accidents, homicides and suicides—that did not involve the brain directly. Immunohistochemistry was performed using the TDP-43 mab2G10 . This antibody is a recombinant human TDP-43 directed to the amino acids MTEDELREFFSQYGDVM of the TDP43 protein and able to identify prominent physiological nuclear immunostaining and neuronal pathological cytoplasmic immunoreactivity in neurons and glial cells in TDP-43 proteinopathy cases.This work included forensic cases from MMC and low pollution controls. A total of 20 subjects  . The logarithm of TDP-43 increased significantly with age (p < 0.0001) and it was higher for MMC residents (p < 0.0001). Excluding ALS cases, a log-transformed linear regression of TDP-43 concentration relative to age and residency showed that CSF TDP-43 increases significantly with age (p = 0.0032) (Mean CSF TDP-43 concentration was significantly higher in ALS versus MMC and non-MMC controls ( 0.0032) .The average age of the MMC adult cases was 41.1 ± 18.9 years and that of the controls was 46 ± 16 y. A 16-year-old MMC boy was also studied. Remarkably, concentrations of TDP-43 in cisternal CSF with an average of 572 ± 208 pg/mL forecasted cortical and subcortical TDP-43 pathology, while averages of 232 ± 130 pg/mL were associated with negative TDP-43 brain pathology in MMC residents and controls.Representative immunohistochemistry photographs are shown in The pathology was mostly seen in brainstem levels, including the medulla and pons, substantia nigrae and locus coeruleus, and in relation to the mesencephalic reticular formation, ventral tegmental area-parabrachial pigmented nucleus complex and caudal-rostral linear nucleus of the raphe .The cortical and hippocampal pathology was characterized by loss of nuclear TDP-43 expression and/or dash-like IR cytoplasmic neurons. The 24 and 25 y old subjects showed negative IR nuclei in frontal and temporal neurons, cytoplasmic IR and oligodendroglia tangles A,B, whil2.5 above current EPA US standards and highly toxic UFPM have CSF TDP-43 concentrations exponentially increasing with age. TDP-43 is the target protein associated with ALS and fronto-temporal dementia (FTD) [Intracellular accumulation of abnormal misfolded proteins is the critical neuropathological feature of ALS, FTD, Alzheimer’s and Parkinson’s diseases and exposure to particulate matter air pollution has been described as a strong risk factor for Metropolitan Mexico City (MMC) young residents ,2,3,4. Mia (FTD) ,66,67,68ia (FTD) ,2, and nia (FTD) ,69, Hasaia (FTD) ,69.The global connectome architecture of FTD subjects is a relevant issue in early TDP-43 pathology, as it allowed researchers such as Shafiei et al.  to identOur TDP-43 CSF findings and the previously documented quadruple brain pathology ,2,3,4 arThe abnormal CSF proteins found in MMC children and young adults are very concerning because they are involved in several pathophysiological mechanisms of early neural damage with eventual impacts on cognitive, neurological and psychiatric outcomes ,75,76.At the core of our results, we report accumulation of TDP-43 starting at an early age in individuals highly exposed to complex environmental emissions, including UFPM ,2,3,4. TNon-fibrillary TDP-43 accumulates in the rough endoplasmic reticulum (RER), as described by Kon and colleagues , and theNeuropathological information in conjunction with the social brain hypothesis  and the The involvement of TDP-43 in the complex reticular formation in MMC residents must be pursued further, given the complexity of the brainstem reticular nuclei and their connections with supra- and infra-cortical structures involving major integration and relay centers coordinating survival functions and key connections between the cerebral cortex, the cerebellum and the spinal cord ,94,95,96Research regarding TDP-43, including novel nuclear pore articles, muscle TDP-43 involvement and the anatomical targets ,110,111,There is an urgent need for noninvasive, reliable fluid biomarkers to diagnose early TDP-43 pathology to improve the differential diagnosis with overlapping neurodegenerative diseases that undoubtedly exhibit an extreme variability in clinical phenotypes, as described by Virgilio et al., for tau . Since Tp < 0.0001), with NfL values higher for all phenotypes of symptomatic FTD-ALS spectrum (FAS) patients compared to primary psychiatric disorders (PPD) [The work of researchers exploring correlations between fluid biomarkers is highly relevant ,121,122.Since, our MMC cases have AD hallmarks, and given that cognition, gait and balance; auditory-evoked brainstem potentials; and brain MRI changes are striking in the young MMC residents ,124,125—−3 [There were advantages and limitations to this study. A major advantage was the multidisciplinary collaborators and the efforts made to exchange viewpoints regarding the importance of early clinical detection of young individuals at risk, key in understanding the impact of our findings in future multidisciplinary studies. The current particle number concentration (PNC) in MMC is crucial environmental information for the responsible authorities. Residents continue to be exposed to an average of 44,000 particles per cm−3 , with alParticulate matter exposures—specifically, UFPM/NP sustained exposures from utero—are likely key in aberrant neural protein pathology. The CSF TDP-43 results identify logarithmic increases related to age across young megacity urbanites, crucial information in view of the 18% TDP-43 pathology reported in 202 forensic MMC autopsies aged 27.29 ± 11.8 y and the overlap of aberrant hyperphosphorylated tau, beta amyloid, α synuclein and TDP-43. These data are striking in view of the work of Karanth et al.  and CarlWe identified a significant relationship between cisternal CSF TDP-43, an average of 572 ± 208 pg/mL, and TDP-43 brain pathology. This is particularly serious for highly exposed children, as with the 16 y old boy (1013 pg/mL) who had extensive nonmotor and motor TDP43 pathology. As toxicologists working with forensic colleagues, we suggest that forensic cases are very helpful to explore the extent of brain pathology in a population at large, and taking a cisternal sample is simple and quick.Defining early markers of the quadruple aberrant neurodegenerative diseases, including TDP-43 pathology, ought to be the core of our future efforts. MMC residents are showing early clinical symptomatology—including gait and balance alterations, cognitive deficits and MRI volumetric cortical and subcortical abnormalities, all of which may help identify young subjects at higher risk.Exposed children and young adults in highly polluted areas need early neuroprotection and multidisciplinary prevention efforts. Control of combustion and friction UFPM sources and engineered NPs  is becoming increasingly important and urgent to diminish the human and economic costs of a global neurodegenerative epidemic.UFPM/NP exposure should be included in any assessment of the neurodegenerative risk profile of exposed individuals. No matter the portal of entry, chronic delivery of exogenous particles to the brain induces oxidative stress and neuroinflammation.We have described the overlap of multiple neurodegenerative pathologies; the presence of anthropogenic UFPM in fetal brains; and the early development of AD, PD and TDP-43 pathology, along with their progression and their neuropsychiatric consequences: this body of knowledge resulting from multidisciplinary studies cannot be disregarded by those concerned with public health.We urgently need to practice preventive medicine and develop tools to identify children at risk in order to implement neuroprotective strategies. As neurotoxicologists, we ought to define the mechanistic pathways involving complex NPs containing metalloids, metals, organic compounds, plastics, etc., that can cause extensive brain pathology. As physicians, our focus should be protecting the brains of our future citizens and our younger generations, identifying neurotoxic emission sources and being active players in multidisciplinary teams to prevent, ameliorate or halt neurodegenerative diseases.


Holey graphene, consisting of graphene sheets with in-plane nanopores, has recently attracted more attention as it expands graphene applications to other fields inaccessible by the pristine graphene. To ensure an effective implementation of holey graphene in the market, it is crucial to explore new preparation methods that are simple, cost effective, eco-friendly, versatile, and scalable. While ball milling of graphite in presence of exfoliating agents was found very effective in the preparation of graphene (doped and undoped) and graphene-composites, this technique remains unexplored for the preparation of holey graphene. In the present work, Nitrogen-doped multilayer holey graphene sheets were prepared by an all-solid, one-step procedure based on high-energy ball milling of graphite as the starting material in presence of melamine in a shaker-type mill for 1 hour under ambient conditions. Melamine acted simultaneously as an exfoliating agent to enhance the exfoliation of graphene layers and a diluent to protect graphite against the continuous fragmentation into amorphous carbon during the high-energy “shock” mode of ball milling. The high-energy “shock” mode of ball milling of graphite in presence of melamine induced the formation of multilayer defective graphene as an intermediate product before being converted into N-doped multilayer holey graphene after the removal of the in-plane defects during the milling process. The characterization of the final product confirmed the formation of N-doped multilayer holey graphene with a content in nitrogen as high as 12.96 at.%, making it promising for energy storage and energy conversion applications. Graphene displays a combination of structural, electrical, thermal, and mechanical properties that position it as an important 2-D material to manufacture a wide range of uniquely enhanced products for various sectors, including clean energy, wearable technology, biomedical devices and aerospace ,2,3.More recently, porous  graphene, consisting of graphene sheets with in-plane nanopores, has attracted more attention because it expands graphene applications to other fields inaccessible by the pristine graphene. The pores in the holey graphene induce more reactivity suitable for applications in water treatment, energy storage and energy conversion ,5,6. Suc2 [2 in the graphite crevices. Another publication from the same group reported an “industrially scalable” method to produce graphene involving the pretreatment of graphite by ball milling in supercritical CO2 [x/TiO2@multilayer-graphene and amorphous MnOx@few-layered graphene, were also fabricated by ball milling [Ball milling has emerged as an efficient, eco-friendly, cost-effective and scalable approach for the production of graphene, doped graphene and graphene-based composites ,11,12,132 . The proical CO2 . N-dopedical CO2  of and/oThe ball milling procedures discussed in the literature for the production of graphene (both doped and undoped) and graphene-based composites are based on the low-energy approach of ball milling  involving the use of “planetary” ball mills. A typical process in the shear-exfoliation mode involves milling balls that are rolling on the inner surface of the milling vials. The shear forces developed due to the rotation of the milling balls unwrap graphene sheets by breaking the out-of-plane C=C bonds, resulting in the transformation of graphite into graphene. Such a mode, although found effective in terms of yield in graphene, involves milling times that are relatively long, which would add extra cost for the scale-up. Another mode of ball milling, typical of shaker mills, is the high-energy approach  involving the application of vertical forces due to the repeated impacts of the milling ball on the graphite grains, resulting in more fragmentation of the particles that could ultimately lead to amorphous carbon. The shear-exfoliation mode of ball milling is regarded as more effective for graphene exfoliation as compared to its the shock-fracture counterpart. The latter is considered as an unwanted mode of ball milling as it induces the fragmentation of graphite into amorphous carbon rather than producing graphene . This leHerein, we report on a simple method for the preparation of nitrogen-doped holey multilayer graphene by co-milling graphite and melamine via high-energy ball mill using a shaker mill. More specifically, we demonstrate that the fragmentation process during the high-energy ball milling could be controlled in such a way to produce the perforation of graphene rather than its complete fragmentation into amorphous carbon. In addition to being cost effective, eco-friendly, and versatile, the proposed method is all-solid and is held under ambient conditions , making it simple and very promising for scale-up.Graphite powder  and melamine powder  were used as the starting materials. In a typical experiment, 25 mg of graphite was milled in presence of 75 mg of melamine (weight ratio of 1:3) in a 5 mL stainless-steel vial  with a stainless-steel ball (6.35 mm diameter) under ambient conditions  using a SPEX 8000M high-energy shaker mill  operated at 1060 cycles per minute (cpm) for one hour. Because of the amplitude and the frequency of the back-and-forth vial vibration, the normal force of the ball’s impact is important. This confers the high-energy character to this type of mill.The purpose of using melamine is to facilitate the exfoliation of the graphene sheets. The mechanism through which melamine is thought to exfoliate graphene sheets the ball milling process was investigated both experimentally and theoretically by Leon et al. . In summScanning electron microscopy images were taken using a JSM-7100F scanning electron microscope . X-ray diffraction pattens were obtained using a Rigaku minifle × 600 diffractometer . UV-Vis absorption measurements on powders’ suspensions in DMF were performed using a Perkin Elmer Lambda 365 spectrophotometer . After washing both pristine  mixture and ball milled powders thoroughly with hot water, Raman spectra was collected using a Thermo Scientific DXR Raman microscope . The average in-plane size equation :(1)La=(2X-ray photoelectron spectroscopy (XPS) spectra were collected using PHI 5000 VersaProbe . Transmission Electron Microscopy images were obtained using JEOL JEM-1011 Transmission Electron Microscope .3H6N) main peak (−301) located at 2θ ≈ 26.1° was identified using the ICDD#00-024-1654 reference patterns, while Graphite main peak (002) located at 2θ ≈ 26.4° was identified using the ICDD#00-001-0640 reference patterns. The (002) peak of graphite broadens, and its intensity decreases after milling. This is indicative of the exfoliation of the graphene sheets through high-energy milling in presence of melamine since the broadening of the (002) peak of graphite is related to the out-of-plane crystallite size that is proportional to number of the graphene sheets stacked in graphite. A broadening if the (−301) peak is melamine is observed, indicating a decrease in the crystallite size of melamine via high-energy ball milling.The effect of the high-energy ball milling was investigated using X Ray Diffraction. An amount of 7 mg of unmilled or ball-milled powders were sonicated in 20 ml of DMF to produce suspensions. No dispersion was observed for the unmilled powders  for 1 hour, making it simple and cost effective. Moreover, it is eco-friendly as it does not involve the use of hazardous chemicals or the generation of harmful byproducts. The proposed method is also versatile because the structure of the multilayer holey graphene, its yield and the nitrogen doping content could be further optimized through the control of parameters such as graphite/melamine weight ratio, balls-to-powder weight ratio, the milling balls and/or milling vial hardness, size of the balls and/or their size distribution in the vial and the milling time. Finally, the proposed method is scalable.