This paper constructs planar-type graphene thin film current collectors for proton exchange membrane fuel cells (PEMFCs). The present planar-type current collector adopts FR-4 as the substrate and coats a copper thin film using thermal evaporation for the electric-conduction layer. A graphene thin film is then coated onto the current collector to prevent corrosion due to electrochemical reactions. Three different coating techniques are conducted and compared: Spin coating, RF magnetron sputtering, and screen printing. The corrosion rates and surface resistances are tested and compared for the different coating techniques. Single cell PEMFCs with the developed current collectors are assembled and tested. A PEMFC module with two cells is also designed and constructed. The cell performances are measured to investigate the device feasibility. The proton exchange membrane fuel cell (PEFMC) adopts hydrogen as its fuel, and the fuel energy is converted into electrical energy through an electrochemical reaction. In portable applications, bipolar plates or current collectors account for the major weight percentage among PEMFC components . In portIn order to shrink the fuel cell size for portable applications, Lee et al. first proposed the micro-electro-mechanical system (MEMS) technique to construct a micro fuel cell . After tAlthough good electrical conductivity is important for micro fuel cell current collectors, corrosion resistance is also very important, as poor corrosion resistance degrades micro fuel cell durability. Related research has been conducted on current collector electrical conductivity, such as coating gold or TiN/TiAlN layers onto stainless steel expanded meshes , depositThe printed-circuit board (PCB) technique was also applied to construct the planar-type portable fuel cell, which was first proposed by O’Hare et al.  and SchmTo avoid distortion due to the mismatch of significantly different material properties between the metal current collector and FR-4 substrate in the PCB fuel cell, a lightweight current collector was proposed by Sung et al.  and KuanA single cell PEMFC was also assembled and tested . Ning etIn addition, the precious metal coating of the current collector is essential for improving corrosion resistance; however, it would increase the total cost of the cell. Optimizing the coating thickness is essential to maintain the balance between the corrosion resistance and cost. Surfaces and interfaces present a significant portion of the workable area and a network of energetically mismatched or metastable molecules, which could be exploited to either control surface reactions, engineer bulk stability, or reveal new fundamental details of those now well understood processes or systems . Lee et The main objective of this paper is to develop lightweight planar-type current collectors for a PEMFC module with two cells. The lightweight current collector also adopts FR-4 as the substrate material; the copper thin film is coated via the thermal evaporation process that functions as the electric-conduction layer. A graphene thin film is further coated onto the copper thin film as the corrosion-resistance layer. The proposed planar-type current collectors were fabricated with three different graphene thin film coating processes. The completed current collectors were assembled into a two-cell PEMFC module. Related performance and stability experiments were also performed.The present lightweight current collector for the two-cell PEMFC module consists of three layers. The first layer is the FR-4 substrate. The second layer is the electric-conduction layer–copper thin film fabricated by adopting the thermal evaporation process to coat copper particles onto the FR-4 surface. The third layer is the corrosion-resistance layer–graphene thin film coating via three different processes discussed and compared in this paper.A geometric drawing of the two-cell current collector is shown in The fabrication process for the electrical conduction layer is shown in The fabrication process for the graphene thin film using graphene ink is shown in The graphene thin film fabrication process uses a graphene suspension, as shown in The graphene thin film fabrication process using graphene dispersion is shown in The measurements on the weight and thickness of the current collectors are shown in The four probe resistance measurements were conducted to ensure electrical conductibility uniformity for the complete current collectors. An illustration of the five current collector monitoring points for surface resistance measurements is shown in The current collector surface resistance values with a graphene thin film using graphene ink, graphene suspension, or graphene dispersion, for the complete current collectors, are shown in Preventing corrosion is also very important for the current collectors. Therefore, the Tafel extrapolation method is conducted to measure the corrosion characteristics. An aqueous methanol solution and de-ionized water are first prepared and mixed as an acidic aqueous methanol solution, the mix ratio of methanol to de-ionized water is 1:9 and the PH value is 6.2. A sample of the fabricated current collector would then be placed in the solution. The Ag/AgCl (3.5M KCl) is adopted as the reference electrode with a platinum counter electrode. Impedance measurements were conducted adopting the BioLogic SP-150AC instrument. The scan rate is 0.166 mV/s and the voltage is −0.025–0.025 V. The results of the Tafel curves are shown in Scanning electron microscopy (SEM) is adopted to investigate the micrographs of the cross-sections of the current collectors coated with different graphene thin films, and this is shown in −2 at the anode, and Pt 0.4 mg cm−2 at the cathode. Silicon gaskets with a 0.15 mm thickness were used for sealing. The cell compression ratio was 34.78%.After completed current collector fabrication, the proposed current collectors were assembled into a two-cell PEMFC module to measure cell performance. PEMFC module with both forced convection air-breathing cathodes and self-air-breathing cathodes were studied. The MEA adopted in this paper is a three-layer catalyst coated type with a DuPont Nafion HP membrane and carbon paper diffusion layers. The reaction area was 5 × 5 cm, the catalyst load was Pt 0.1 mg cmAn exploded drawing of the two-cell PEMFC module with a forced convection air-breathing cathode is shown in The PEMFC module performances with forced convection air-breathing and three different types of graphene coatings were conducted at different anode hydrogen and cathode air flowrates. The anode hydrogen flowrate and cathode air flow rate ratios were kept at 1:2 in the experiment. Both the anode hydrogen flow and cathode airflow were humidified and kept at 50 °C. The anode hydrogen/cathode air flow rates of 25/50, 50/100, 100/200, 200/400, 300/600, and 400/800 sccm were investigated.A performance comparison of the PEMFC module with a forced air-breathing cathode and the corrosion-resistance layer using graphene ink coating is shown in −2 at the low flow rate (25/50 sccm), the further reduction of the operating voltage leads to a sharp drop of the current. This is due to the insufficient reactant, and the fuel cell becomes highly unstable, the cell performance is sharply dropped and is without a smooth transition through the ohmic loss to the concentration loss. Therefore, the low flow rate condition is not suitable for the cell operation at the high-current range for the current collector with the graphene ink thin film.In the high-current range of higher than 75 mA cmThe PEMFC module performance is decreased when the flow rates are increased. The PEMFC module performance comparison with a forced air-breathing cathode and a corrosion-resistance layer using a graphene-suspension coating is shown in −2 at the low flow rate (25/50 sccm), the further reduction of the operating voltage will lead to a sharp drop of the current. The results also show a similar trend to the current collectors with a graphene ink coating and the related explanation refers to the The performance comparison of the PEMFC module with a forced air-breathing cathode and the corrosion-resistance layer using a graphene-dispersion coating is shown in The results show that the current collectors with three different types of graphene thin film show similar phenomena and trends. In addition, the current collector using the graphene-dispersion coating presents the highest performance, using graphene suspension is second, and using graphene ink presents the lowest PEMFC module performance.The PEMFC module performances with self-breathing and three different types of graphene coatings were further conducted at the anode hydrogen flow rate of 100 sccm. The anode hydrogen flow was humidified, kept at 50 °C and a 100 sccm flow rate. The cathode side was open for self-air-breathing and the ambient temperature was 25 °C. The performance comparison of the PEMFC module with self-air-breathing cathode and the corrosion-resistance layer is shown in Although the surface resistances are roughly the same for all cells via different graphene thin film coatings in According to the measurements in After investigating the PEMFC module performance with the developed current collectors for both forced air-breathing and self-air-breathing cathodes, long-term stability tests of the PEMFC modules, with self-air-breathing cathodes, using three different graphene coatings as corrosion-resistance layers, were further conducted. Experiments were performed at a 100 sccm anode hydrogen flow rate and the hydrogen was humidified and kept at an inlet fuel temperature of 50 °C. The cathode side is open for self-air-breathing and the ambient temperature is 25 °C. The PEMFC module stability tests with self-air-breathing cathodes and different types of corrosion-resistance layers under 1 V loads, are shown in The results show that both the PEMFC modules with current collectors using graphene-dispersion and graphene-suspension coatings are quite stable. The PEMFC module performance with the collectors using the graphene-dispersion coating is slightly higher than that using the graphene suspension. Although the PEMFC module with current collectors using the graphene ink coating also showed good stability, the PEMFC module performance is distinctly lower than those using the graphene dispersion and graphene suspension. The results also successfully show the feasibility of the developed current collectors in portable applications. However, the tests only represent approximately a 10 h operation period, which is much less than the anticipated life specification. Therefore, additional longer duration tests, particularly under realistic cycling conditions that accelerate degradation, should be made in the future for realistic commercialized applications .This paper proposes lightweight current collectors and constructed a PEMFC module with two cells. The current collectors consist of a FR-4 substrate, a copper thin film as the electric-conduction layer, and a graphene thin film as the corrosion-resistance layer. The copper thin film is accomplished by a thermal evaporation process. Three different graphene coating processes to fabricate the graphene thin film were investigated. The results show that adopting a graphene-dispersion coating has the best corrosion-resistance capability, the graphene-suspension coating is second, and graphene ink is the lowest. Further study of the fabricated current collectors assembled into a two-cell PEMFC module show that the current collectors with a graphene-dispersion coating have the highest PEMFC module performance, the graphene-suspension coating is second, and graphene ink also has the lowest PEMFC module performance. The graphene-dispersion thin film shows the lowest coating weight and superior surface flatness, and the graphene ink thin film shows a significantly higher coating weight, voids inside, and an uneven surface in the testing results. Long-time stability studies were also conducted, and all three graphene coating processes showed good PEMFC module stability after long-term operations. During the long-time stability tests, the PEMFC module performances for the current collectors that used a graphene-dispersion coating are a little bit higher than for the current collectors that used a graphene-suspension coating. These performances were both clearly higher than those of current collectors that used a graphene ink coating. The feasibility studies also showed the potential of the developed current collectors in portable applications.


In cold climate regions, the energy associated with indoor heating constitutes a large portion of energy consumption. Increasing energy utilization efficiency is critically important for both economic and environmental reasons. Directly converting electrical energy to thermal energy using joule heating construction elements can save energy and investment to the water pipelines which have been extensively used for indoor heating in China. The fired brick has been extensively used to make pavements, walls and other masonry. Taking advantage of the high dispersion quality of graphene oxide (GO) in water, as well as the firing process used to make fired bricks, graphene nanocomposite bricks with excellent electrical properties and improved mechanical performance were prepared in China. The compressive strength of the bricks showed a substantial increase from 3.15 MPa to 7.21 MPa when GO concentration was 0.1 wt.%. Through applying 5 volts of electrical field within 5 minutes, the nanocomposites can be heated from room temperature to 60 °C, 110 °C and 160 °C for the nanocomposite bricks with graphene concentration of 3 wt.%, 4 wt.% and 5 wt.%, respectively, due to the extremely low percolation threshold (~0.5 wt.%) and high conductivity (10 Ω·cm at 1 wt.%). The sheets were connected more tightly when the GO content was increased. The thermal efficiency can reach up to 88% based on the applied voltage, measured resistance and temperature rise curves. Indoor heating has been recognized as the main energy consumption source, particularly for cold climate regions—such as North China, that experiences a prolonged period of extreme cold weather below −20 °C) . It is p0 °C . ItIn the last decade, a great deal of interest has been focused on phase change materials (PCMs)—which are mainly based on carbonaceous materials like nanotubes (CNTs), and graphene oxide (GO)—to use solar energy to store heat. For instance, Xiang et al.  studied The high dispersion quality of nano additives in matrix is essentially the most important prerequisite for the property enhancement of nanocomposites. The past decades have witnessed the improvement of the dispersion of various nanomaterials in polymer matrix and the corresponding enhanced properties of nanocomposites ,18. HoweGraphene, as one type of two dimensional (2D) nanomaterials, which possesses extremely high mechanical, thermal and conductive properties which are all essential characteristics for the application of self-heating ,22. In rBrick has a long history of being a construction material, and it has been extensively used to make walls, pavements and other elements in masonry construction ,25. AmonGraphene oxide (GO) used in this experiment was synthesized with improved hummer’s method , and theThirty specimens of cuboid sintered graphene bricks were prepared, the specimens were divided into 10 groups according their GO contents . Each formulation of graphene bricks had three repetitive samples. The dimension of specimen is 10 mm × 10 mm × 40 mm.The fabrication process of the graphene bricks in this experiment is presented in ρ is the resistivity (Ω·cm), R is the resistance (Ω), S is the cross-sectional area of graphene bricks (cm2), and L is the length of graphene bricks (cm).During the sintering process, GO was reduced to graphene, which made the graphene bricks have electrical conductivity. Resistivity was employed to evaluate the conductivity of graphene bricks. Low resistance was measured by UNI-T UT51 multimeter and 2450 source test unit (KEITHLEY), and high resistance (more than 200 MΩ) was measured by electrochemical station . In addition, the dimensions of sintered graphene bricks were measured by electronic vernier caliper with the accuracy of 0.01 mm (Guanglu brand). The test process was shown later. The resistivity was calculated according to the following formula:ATTEN APS3003 Si DC power supply and K-type thermocouple were applied to measure the heating performance of graphene brick. The graphene bricks were placed in a foam box to prevent heat loss, and a thermocouple was attached to the surface of the specimen, then a different voltage was applied, and the changes of temperature were recorded over time.A specimen with dimensions of 10 mm × 10 mm × 40 mm was used to test flexural strength of graphene bricks. The graphene bricks were cut into three small cube pieces (10 mm × 10 mm × 10 mm) and polished before testing. The WDW-100 computer controlled universal testing machine  was used to test the mechanical properties of graphene bricks. The loading speed was 0.02 kN/s. The elastic modulus in the compression of graphene bricks was calculated by the slope of the elastic stage of the stress-strain curve. The peak value in each curve was considered the compressive strength of the specimen.To investigate the mechanism of graphene bricks and the degree of reduction in GO, X-Ray Diffraction  and X-Ray Fluorescence  were employed to analyze the phase composition. X-ray photoelectron spectroscopy  and Fourier Transform Infrared Spectrometer  were employed to study the changes of the chemical environment of the GO-clay composite after thermal reduction. A scanning electron microscope  was used to observe the microstructure of specimens.As can be seen in The XPS data of specimens in −1, 3618 cm−1 and 3445 cm−1 reflect the stretching vibration of -OH: 3695 cm−1 corresponds to the -OH vibration in the kaolinite interlayer, 3618 cm−1 corresponds to the -OH vibration between the kaolinite silicon layer and the aluminum layer, and 3445 cm−1 corresponds to the vibration of -OH in the absorbed water in the sample [−1 represents the bending vibration of -OH in absorbed water and the vibration of aromatic C=C in GO [−1, 3618 cm−1 and 3445 cm−1 disappeared due to dehydration and dehydroxylation during heating [−1 can be obtained, which is the vibration of aromatic C=C in GO. Before sintering, the peaks in the FTIR spectra corresponding to 1043 cm−1, 774 cm-1, 691 cm−1, and 476 cm−1 are generated by Si-O vibration in quartz and kaolinite [−1 is generated by the bending vibration of Al-OH, and 535 cm−1 is generated by the vibration of Al-O in the kaolinite [−1,798 cm−1 and 471 cm−1—are formed, which correspond to the stretching vibration of Si-O, the vibration of Si-O-Al, and the bending vibration of Si-O, indicating the transformation of kaolin to metakaolin [−1 implies the formation of γ-Al2O3 [The FTIR spectra further describes the changes in the chemical environment of nanocomposite in e sample ,31. Besi=C in GO ,31. Afte heating ,31. Onlyaolinite ,31. A peaolinite . After s γ-Al2O3 , which l γ-Al2O3 , it is s10 Ω·cm to about 1000 Ω·cm, when the GO content at 0.5 wt.%. Electrical resistivity further dropped to about 100 Ω·cm, when GO content beyond 1 wt.%, which indicating that with the increase in GO content, the electrical resistivity decreased significantly, and the conductivity was significantly optimized. The electrical percolation threshold is dependent on the characteristics of the matrix, nanoadditives and the dispersion quality. For example, Wen et al. [n et al.  found thn et al. . Such lo−7 mol/mL in clay/water with a GO content of 0.2 wt.%, to 7.55 × 10−7 mol/mL in clay/water with a GO content of 2 wt.%, and to 4.1 × 10−6 mol/mL in clay/water with a GO content of 20 wt.% within 10 min. The dispersion stability of GO is highly dependent on ionic concentration, and a concentration of ~10−5 mol/mL could induce the agglomeration of GO [on of GO , which mThe self-heating performance of CGCBs were investigated for the potential application in house heating, as presented in With the increase in graphene concentration and the electrical conductivity maintained at a stable level, the graphene network became more compacted with more distributed paths for heat generation and transfer, thus sharply enhancing the self-heating properties. Based on the applied voltage, measured resistance, and temperature raising curve, the calculated heating efficiencies were 87%, 88%, 78% for the samples with a graphene concentration of 3 wt.%, 4 wt.% and 5 wt.%, respectively, when the samples were heated from room temperature (RT) to 50 °C, which are much higher than that of coal and gas. This demonstrates that graphene is one of the most conductive electrical/thermal materials. In addition, the self-heating process can be even faster when higher voltage is applied.The mechanical properties of graphene bricks were tested as shown in (1)High concentration GO is beneficial to the increment of compressive strength, flexural strength and elastic modulus of CGCB. Compressive strength, flexural strength, and elastic modulus showed similar increasing trend when the concentration of graphene was higher than 3 wt.%, indicating the recovery of the reinforcement effects of graphene.(2)There is a small time window that allows us to disperse GO uniformly in clay matrix before the ionic strength becomes too high. With the increase in graphene concentration and the electrical conductivity maintained at a stable level, the graphene network became more compacted with more distributed paths for heat generation and transfer, thus sharply enhancing the self-heating properties.(3)The temperature ramping curve is highly dependent on the graphene concentration under a given external voltage. For the samples with 1 wt.% graphene, the temperature only increases from 22 °C to 30 °C within 500 s, and then becomes saturated. When the graphene concentration increases to 3 wt.%, the sample can be heated quickly from room temperature to 73 °C in 600 s without any temperature saturation observed afterwards.(4)The results from XRD, XPS, FT-IR and SEM proved that graphene was uniformly distributed across the whole matrix, and covalent bonding was formed between clay and GO. The thermal efficiency can reach up to 88% based on the applied voltage, measured resistance and temperature rise curves. The graphene nanocomposite bricks can serve as part of a smart building with using series connection method to share voltage to fit different circumstances, which also sheds lights on the development of intelligent buildings through promoting the combination of nanomaterials and building materials.This study investigated the synthesis of graphene brick nanocomposites with GO, and studied the micro-structure, mechanical and self-heating properties of CGCB. From the experimental results and micro-structure analysis, the following conclusions can be made:


I-V characteristics of the graphene after molecular  adsorption. The results show that gas adsorption modulates the energy band structure of the graphene that leads to the variation of the energy bandgap, thus the DOS changes. Consequently, graphene converts to semiconducting material, which affects the graphene conductivity and together with the DOS variation, modulate velocity and I-V characteristics of the graphene. These parameters are important factors that can be implemented as sensing parameters and can be used to analyze and develop new sensors based on graphene material.Over the past years, carbon-based materials and especially graphene, have always been known as one of the most famous and popular materials for sensing applications. Graphene poses outstanding electrical and physical properties that make it favorable to be used as a transducer in the gas sensors structure. Graphene experiences remarkable changes in its physical and electrical properties when exposed to various gas molecules. Therefore, in this study, a set of new analytical models are developed to investigate energy band structure, the density of states (DOS), the velocity of charged carriers and  Electronics and sensors are required to provide valuable advantages for humanity in different vital areas such as life sciences, health care, and security. Electrical sensors are electronic devices capable of detecting physical quantities in their environment and convert them into measurable electrical signals that can be displayed by the monitor ,2,3. Sen2, H2O, and NH3 at room temperature [I-V formula to calculate the transfer characteristics of transistors with graphene as a channel. These properties are important factors that can be used to monitor sensor properties and investigate its performance against the adsorption of gas molecules. Sensor modeling can guide the experiments by showing the possible behavior and how these behaviors depend on the methods that are chosen in simulation.Over the last decade, graphene as a two-dimensional material has been suggested and studied for various practical applications. It has unique electrical, chemical, and structural properties; therefore, graphene outperforms its counterparts for sensing applications ,14,15. Iperature ,23,24. Sperature ,26,27. Iperature ,30,31,32perature ,34. The perature ,36,37,38perature ,41,42,43It has been proven that the electrical and physical properties of the graphene indicate outstanding variation after exposure to the various target analyte of the gas molecules. These variations can be implemented as sensing parameters to monitor adsorption of various gases on the graphene surface and develop sensors with high selectivity and sensitivity.The schematic of a graphene field-effect transistor-based sensor is illustrated in This leads to the transition of graphene from metallic to semiconducting energy state and modifies the electrical conductance of the graphene channel in the graphene-based FET. The changes in the energy band structure, bandgap, and the number of charged carriers in the transistor channel lead to modify the density of stats, carrier concentration, and thus, carrier velocity, resulting from modulating the current-voltage properties of the sensor.The presented study is somehow analogous to our previous work  but has On the other hand, in the previous model, the on-site energies of the adsorbed gas molecules were not considered in the modeling, and the energies of the carbon atoms of the GNR and adsorbed molecules were considered to be the same. But in the current models, we differentiate between different types of gas molecules and with carbon atoms of the graphene.2, H2O, are chosen to be applied for sensing purposes. These three gasses are famous gases that are extensively being used in industrial and medical applications. We use three different gases to evaluate the proposed models and to show that the proposed models can predict different types of gas molecules. In addition, we used perfect graphene for mathematical formulation and modeling of the gas sensor. However, for future studies, the current modeling technique can be modified to apply for the defected graphene as well, as defected graphene can provide higher sensitivity and faster response and recovery time [Here, three random gases CO, NOery time ,46.In the graphene energy band structure, the valence and conduction bands overlap in Dirac points that makes graphene to have no energy gap . The elenmH is the Hamiltonian operator matrix, nφor m is the column vector representing the wave function in the unit-cell n or m, and E is energy [To calculate the low energy band for graphene, the tight-binding technique is adapted. In our tight-binding model, graphene as a 2D material is incorporated with the assumption that there is only one orbital per atom leading to the ultimate matrix form of the Schrödinger Equation as :(1)∑m[Hns energy . The schth unit cell) has four closest neighbor unit cells. In addition, each unit cell consists of two carbon atoms. Therefore, based on the theory that employs a single orbital per carbon atom, a (2 × 2) Hamiltonian matrix indicating the valence and conduction band in the energy band structure can be achieved. In the Hamiltonian matrixes, the upper or lower diagonal matrix elements for the neighbor carbon atoms of the graphene are assumed as t, while the rest of them are zeros.To calculate the energy dispersion relation for graphene, we need to solve the above Schrödinger Equation. Thus, first, we should acquire Hamiltonian matrixes for the graphene unit cells. Each graphene unit-cell E=E0+Once the impurity molecules adsorbed on graphene, the on-site energies of the adsorbed molecules and the hopping energies between gas molecules and graphene, contribute to the graphene characteristics and modify its electrical and physical properties such energy band structure, density of states, concentration, and velocity of carriers and current-voltage properties. To model gas effects on these parameters, the tight-binding (TB) approach based on the nearest neighborhood is employed for the graphene in the presence of the gas molecule. This time, our Hamiltonians will be (3 × 3) matrixes in the presence of the gas molecules. On the other hand, in our Hamiltonians, a single contact between the adsorbate and carbon atom is presumed as depicted in n’ and its four nearest neighbors considering the adsorbed molecule can be described as:Similar to Equation (2), according to the tight-binding model based on the nearest neighbor approximation, the Hamiltonian matrixes for the unit cell ‘thn unit cell and its four neighbors, and then calculating the determinants of the h(k), the energy dispersion model for graphene, considering the molecular adsorption effects, is achieved as:t’ is the hopping integral parameter that shows the hopping energy between the carbon atom and the adsorbate. The value of the 0E is set to be zero as the origin of the energy [t’ will have different values depending on the nature of the target gas molecule. In the case of the graphene without gas, the value of the t’ is zero; by tuning it to non-zero quantities, the gas adsorption effects can be applied. By summation of individual matrixes over the e energy . The val2, CO, and H2O gases. Each gas molecule prefers different configurations on the graphene plane. In our study, the orientation and molecular distance from the graphene surface are considered according to work presented in [αβt is the hopping energy parameters between the substrate and adsorbate, Rt is hopping parameter between the atoms of the adsorbate (carbon atoms for graphene), Rd = 1.42 Å is the carbon-carbon bond length in graphene, and αβd represents the distance between the adsorbate and substrate. Therefore, the hopping energies for the adsorbed gases are presented in To investigate the sensing properties of the graphene, we assumed the adsorption of NOented in . On the ented in :(8)tαβ=t2, and H2O molecules, the energy gap of graphene shows remarkable increments, while CO and H2O have the lowest and highest impact on the bandgap respectively.The adsorption effects of these three gases on the energy bandgap of graphene are investigated. The band structure analysis indicates that molecular adsorption can modify the band structure of the graphene, as illustrated in I-V characteristics. It has been reported by previous studies that the velocity of the carriers is proportional to the density of states and carrier density at any moment, as given by [f)/kBT))f(E) = 1/ is the density of states and n is the carrier concentration. The magnitude of the velocity is given as:*m is the electron effective mass. To calculate velocity, first, we should find D(E) and carrier concentration. The DOS in a material describes the number of states at each energy level that can be taken by the electrons per energy interval, that is calculated as:A is the graphene surface area and the wave propagation vector, xk, in the x-direction is formulated as:When gas molecules adsorbed to the graphene surface, it modulates the energy bandgap and also the carrier concentration. The bandgap variation leads to the variation of the density of states. On the other hand, according to the literature, the velocity of carriers is a function of the density of states and carrier concentration. Now, we are going to model gas adsorption effects on the density of states and carrier concertation and study effect on the carrier velocity in the form of given by :(9)vav=∫The gas adsorption effect on the graphene density of states against the wave vector is illustrated in The next step is to calculate the carrier concentration. The concentration of carriers is a function of the density of states and Fermi function given as :(13)n=∫DBased on Equations (13) and (11), we can write:With the normalized fermi function ^14 for our graphene, which is consistent with the literature [Based on Equation (15), the carrier concentration of graphene is presented in terature ,52.Now, according to Equation (11), to model the carrier velocity, the numerator is calculated as:BT + EgE = x.k, normalized fermi function ƞ, and x, Equation (16) could be modified as:Bk is the Boltzmann constant and T is temperature. Finally, the carrier velocity for the graphene considering the molecular adsorption effects is achieved as:Having t’ and The parameters I-V characteristics based on the carrier velocity. Based on the relation between I-V and velocity, the I-V can be written as a function of the carrier velocity:A represents the surface area, which carriers travel through it, n represents the carrier concentration and q is the electrical charge. Finally, based on Equation (20) the electrical properties of the gas sensor can be investigated. The investigation of the carrier velocity variation after the gas adsorption is performed in the form of current-voltage analysis. Hence, we need to obtain the I-V characteristics of the gas sensor in the exposure of CO, NO2, and H2O are plotted, as shown in The I-V of the sensor. After gas adsorption, the graphene energy bandgap increases, thus, the conductivity decreases and reduces the current. Moreover, the response of the gas sensor against adsorbed molecules is calculated and presented in 2O and the lowest for the CO molecules. This result is consistent with the band structure and I-V analysis as we saw more bandgap increment and current decrement after H2O adsorption than other molecules.In addition, the transfer of charge between substrate and adsorbate changes theG carrier concentration on the graphene surface. The variation of DOS and carrier concentration affect the velocity of the carriers that lead to change the For future investigations and further evaluation of the models, the comparison study with the results of similar studies such as first principle calculations or experimental data can be conducted, as we couldn’t find similar work at the present time. However, according to the archived results and trend of the plots, the proposed models illustrate reasonable performance. In addition, the range of values of the IV, velocity, band structure, and other plots indicates reasonable quantities and, thus the proposed models seem to be valid. 2, and H2O detection. Based on the results, it was shown that the energy dispersion relation of the graphene varies when exposed to the gas molecules. The DOS and carrier concentration parameters were calculated, and the variation of the DOS in after molecular adsorption of the gases were monitored. Based on the DOS and carrier concentration models, the carrier velocity model was developed and analyzed in the form of current-voltage properties. The I-V analysis indicates that the current of the sensor has changed and decreased after the adsorption of the gas molecules. After gas adsorption, the graphene energy bandgap changes that affect the conductivity of the graphene and increase the channel resistance. On the other hand, after molecular adsorption, the change transfer between molecules modifies the number of the carriers and hence the velocity of the charged carriers on the graphene plane that leads to modulate the I-V characteristics. It can be seen that the most and the least current reduction have occurred after H2O and CO adsorption, respectively. This implies that the response of the sensor is not the same for different gases. Finally, the main outcomes of this study can be mentioned as: (i) the analytical formulation, which allows the convenient use of the results for simulators, (ii) the demonstrated selectivity of the sensors with respect to different gases.In this study, a series of analytical models for the detection of the gas molecule using a platform based on graphene FET is developed and applied for CO, NO


High rates of unemployment among people with disability are long-standing and persistent problems worldwide. For public policy, estimates of prevalence and population profiles are required for designing support schemes such as Australia’s National Disability Insurance Scheme; for monitoring implementation of the United Nations Convention on Rights of Persons with Disabilities; and for monitoring service access, participation, and equity for people with disability in mainstream systems including employment. In the public sector, creating a succinct identifier for disability in administrative systems is a key challenge for public policy design and monitoring. This requires concise methods of identifying people with disability within systems, producing data comparable with population data to gauge accessibility and equity. We aimed to create disability-related questions of value to the purposes of an Australian state and contribute to literature on parsimonious and respectful disability identification for wider application. The research, completed in 2017, involved mapping and identification of key disability concepts for inclusion in new questions, focus groups to refine wording of new questions, and online surveys of employees evaluating two potential new question sets on the topic of disability and environment. Recommendations for new disability-related questions and possible new data collection processes are being considered and used by the leading state authority. Australia is among the countries recognising the rights of people with disability to participate fully in society and enjoy all the same opportunities, rights, and access to services as the rest of the community. In 2008, Australia ratified the United Nations Convention on the Rights of Persons with Disabilities (UNCRPD) , and nowData are therefore required on participation by people with disability compared to other citizens of the country, as well as on access to services, both specialist and mainstream. Relevant and efficient data collection requires concise methods of identifying people with disability within administrative systems, as well as the ability to compare the resulting data with population data in order to gauge accessibility and equity. Creating a succinct disability “identifier” for use in administrative systems is a key challenge for public policy design and monitoring in any country ,3,4.Meeting this challenge involves the design and adoption of short question sets, ideally a single question, in order to identify people with disability consistently within service data systems and monitor their access to, and experience of, generic services such as health and education, and to establish employment and other participatory experience in society . A “disaWorld Report on Disability [The need for data development is illustrated by trends and data difficulties in important policy areas including employment and was recognised as a key need in the sability . Despitesability , pp. 49–The picture in the Australian state of New South Wales (NSW) public sector is no better, with the reported proportion of people with disability employed dropping from 4% in 2008 to 2.8% in 2016 . A targThe decision of employees to report their disability status is complex; people with disability, when interviewed, cited reasons such as stigma, fear of discrimination, and irrelevance to work being performed in deciding not to share this information . This isThe Workforce Profile (WFP) is an annual census of the NSW Government workforce that has been collected since 1999. It captures a range of de-identified demographic information from employees of the NSW public sector that is extracted by government agencies from human resource (HR) systems. It collects information related to disability and environmental modifications—whether someone has indicated they have a disability, and whether they require an adjustment. In 2018, for example, representation of people with disability in the NSW public sector workforce was 2.5% [The People Matter Employee Survey (PMES) is a perception survey that encompasses the whole of the NSW government and is led by the PSC. While its focus is on understanding the engagement and experiences of its workforce, it also collects information on a range of demographic information and disability. It is an anonymous survey. Each year a higher proportion of respondents declare a disability than the WFP. In 2018, for example, 3.7% of survey respondents identified as having a disability .The NSW PSC has a number of data collections designed to help it understand the needs of diverse employees, including people with disability:This project aimed to create disability-related questions of value to the purposes of the NSW state PSC and contribute to the literature on parsimonious and respectful disability identification for wider application. Research was designed around the needs of the NSW PSC to inform recommendations on the wording of items in the WFP collection, to better (a) identify people with disability working in the public sector and (b) seek information on workplace modifications needed to promote full and effective participation in the workplace.Improve the response rate to disability-related questions.Improve the quality of data about disability and accessibility in the NSW public sector.Compare the NSW public sector workforce with the NSW population .Provide a better evidence base to inform policy interventions.Specifically, the project reviewed the existing questions relevant to disability in the WFP and developed and tested new potential questions about disability (D questions) and the environment (E questions) to inform recommendations for changes to existing questions in the WFP, toThe detailed objectives of the project were to develop and trial disability-related questions and to assess how the questions were received and interpreted by NSW public sector employees, in order to ensure their appropriateness for use and inform change to questions in the WFP collection. The intention was to improve the quality of NSW public sector data on accessibility and disability representation in the WFP, assist in monitoring equity outcomes, and inform policy interventions to build a more inclusive and accessible workplace.The project was undertaken in a partnership involving the NSW PSC, University of Sydney, and Department of Family and Community Services (FACS). The advisory sub-group (DEAC ASG) of the Disability Employment Advisory Committee (DEAC) comprises public sector employees with lived experience of disability; nominees were invited to join the project team. The DEAC itself consisted of disability peak body representatives, as well as experts from academia and the private sector. It advised the NSW government on improving the representation and inclusion of people with disability in the public sector. The DEAC was invited to comment over the course of the project. Four University of Sydney researchers, expert in the field, were project advisors.The project was completed in three stages in 2017: (1) mapping and identification of key disability concepts for inclusion in new disability-related questions, (2) focus groups with NSW public sector employees to refine wording of new draft questions, and (3) online surveys to trial two potential new question sets with a wider group of employees. The University of Sydney gave ethical approval for the focus groups (no. 2017/132) and the online survey (no. 2017/254)—Stages 2 and 3.Stage 1: Mapping and identification of key conceptsTo identify key concepts for inclusion in disability-related questions, we examined 10 instruments of potential significance and relevance to disability data collection and measurement in the NSW public sector with reference to the International Classification of Functioning, Disability and Health (ICF) . The metThe ICF is the world standard framework and classification for organising information and data about functioning and disability. It defines the main components of functioning as body functions and structures, and activities and participation. It includes a classification of environmental factors to describe the physical, social, and attitudinal environment in which people live and conduct their lives. Environmental factors have a crucial effect (as facilitators or barriers) on people’s functioning and on the creation of disability in many life areas, including the workplace. The ICF represents a biopsychosocial model of disability, combining both the medical and social models of disability, thus recognising that disability may require both individual support and social, environmental change .The ICF enables the collection and comparison of data relating to functioning and disability in many fields and is particularly suited to the present study; it provides a framework to underpin monitoring of implementation of the UNCRPD ,12,16. TTen instruments were selected for mapping to the ICF, on the basis of their significance to the disability field, their relevance to disability data and measurement, and Australian population data that could potentially be compared with NSW public sector data. The selected instruments were the UNCRPD ; ABS SurTwo authors carried out the mapping, one doing the initial mapping and the other cross-checking the results. Points of difference were discussed and resolved to reach consensus.Stage 2: Focus groups to refine wording of new draft questionsThe key concepts and terms identified in Stage 1 were used in different combinations, to draft five D questions (designed to identify employees with disability) and five E questions ; these questions were tested in focus groups with NSW public sector employees . The aimOf the possible focus group approaches, we used the nominal group technique ,30. ThisThe method and protocol for the focus groups were developed by the University of Sydney authors in collaboration with the PSC, and in consultation with members of both public sector departments and the DEAC ASG.Five focus groups were held over an eight-day period in March–April 2017, in three locations . An email invitation for focus group volunteers was forwarded by senior office holders and key contacts in the NSW public sector for distribution within their agency cluster (administrative arrangements that bring together different but related NSW public sector agencies), and DEAC ASG members and others with specific responsibility for diversity, including disability.At least three of the authors were present at each focus group. A senior representative of the PSC involved in the project introduced the project and facilitators; a PSC note-taker was also present, with both PSC representatives joining discussions. Facilitators were University of Sydney project members.Do you think the question is user friendly? What changes do you think should be made?” The facilitators employed an iterative approach in group discussions using comments and opinions expressed by group participants to identify preferred concepts and those to exclude, then develop majority agreement on the terms and phrases preferred. All participants were encouraged to engage in the discussions. At the end of each focus group, a formal voting process invited participants to indicate anonymously their preference for two D and two E questions by placing an adhesive sticker on print-outs of all questions.Each focus group commenced with an attendee orientation to the purpose of the discussion, and “rules” were explained . Facilitated discussions followed, about the draft D and E questions. Participants were asked probe questions such as “The analysis of the feedback from the focus groups involved synthesis of notes from all sessions. Links between question preferences and comments about preferred concepts, terms, and phrases were identified and discussed among all authors. Two new D questions and two pairs of new E questions were then developed byUsing the key preferred concepts as the building blocks for questions, e.g., participation, environment, barrier.Reviewing focus group suggestions about the wording of questions and excluding or including particular terms and phrases.Using notes from the focus groups to inform the connecting words and phrases for the questions, e.g., “having” or “experiencing” difficulties or disability.The D and E questions drafted after the focus groups were further refined after comment from project advisors from the University of Sydney and informal comments from key ABS staff. Two D and two pairs of E questions to be evaluated in Stage 3 online surveys were agreed after final discussion at a full team meeting .Stage 3: Online surveys to evaluate two draft question setsIn the final stage of the project, the two D questions and two pairs of E questions produced in Stage 2 were tested in two online surveys of a wider group of NSW public sector employees . Online accessibility was checked by a specialist, leading to wording changes.The survey instrument was constructed over several iterations, involving the whole project team and further consultation with DEAC ASG members. Two surveys were prepared to allow for presentation of test questions in a different order, and to avoid preferencing particular responses . At thisAn email invitation to participate in the online survey was forwarded for distribution to the key disability contacts including the DEAC sub-group members, senior office holders for distribution to diversity employee networks (including disability) in their agency, and to employees more generally. The invitation emphasised the purpose of the project and specifically the online survey. The voluntary and anonymous nature of employee contributions was clarified in the invitation and participant information statement. People who responded that they were interested in participating were then sent one of the two surveys, according to their administrative cluster. A sample size goal of 200, for each questionnaire, was set in order to enable cross-tabulation of responses by broad demographic information. Surveys 1 and 2 were sent to respondents according to their cluster; that is, to approximately equal numbers of people based on cluster sizes of public sector agencies. In practice, this approach was modified, given the low responses to Survey 2 initially, and respondents after an extended deadline were provided with Survey 2.Results for the three stages of the project informed each following stage, resulting in one recommended D question and two pairs of recommended E questions for further consideration and development by the PSC .Stage 1: Mapping key conceptsThe 10 instruments examined all had some concordance with the ICF. Accordingly, there was considerable overlap in key concepts and terms included in several instruments, indicating potential to produce comparable data. There was variation in emphasis placed on the three ICF components , and in the language and terms used to describe and capture data in these areas. The ABS SDAC was the most comprehensive of all the instruments examined, although it, like several others, was limited in its use of the environmental factors , representing input from 15 agencies. Each focus group (9–16 people) ran for 2.5 h. No participant was asked to disclose whether they had lived experience of disability, although a number elected to do so; the group discussions reflected representation of the lived experience whereby participants disclosed at least 15 different disabilities and long-term health conditions amongst attendees. Given the aims of the study—namely, how best to elicit information to indicate disability—asking for such information in any form would have introduced circularity into the research.Participant preferences on D and E questions, as voted at the end of each session, were tallied across the five groups. The most preferred D question was D4, followed by D3, and then D2; all these questions used key concepts or terms: “participation”, “impairments”, “long-term health conditions”, and “difficulties”. The preferred E question was E1, followed by E2, then E5; all these questions used key concepts or terms: “participate”, “equal”, “environment”, and “change”.The implications about key words are difficult to interpret without the benefit of detailed comments on question structure, the format of lists used, and other expressions and terms. For example, the favourite D questions did not use the word “environment” and did use “not accommodated”, while the E questions (focused on the working environment) were preferred when they included “environment” and “enable” (E1 and E2) rather than “accommodate”.Focus group members considered each question needed revision, with no D nor E question considered “final”. On completion of all focus groups, the project team drafted revisions on the basis of comments and opinions expressed by focus group participants . The newBox 1Use “work environment” rather than “workplace” as many people move around in their work .Use a list rather than sentence for environmental factors.Refer to “your environment” not “the environments”.Terms such as “equality”, “on an equal basis”, or “equal opportunity” may be confused with diversity policies or imply comparisons with peers.Mentioning “long-term health condition” is OK if used alongside “impairment”.How to answer if you have an impairment but no everyday difficulty (because of management and environment)?“Enable” a good word.“Participate fully and effectively” discussed at length—and various alternatives offered.The focus groups also began the process of obtaining comments on the draft introduction to the disability-related questions for use in the WFP, their likely effect on people’s responses, and the resulting data quality. Concerns were expressed about the use of data and its confidentiality, for example, concerns about potential disincentive to complete disability-related questions unless there was re-assurance on the use of data and its confidentiality, particularly regarding potential impacts on employment conditions and outcomes. Focus group participants advocated a simple explanation, which would give respondents answers to questions such asWhy are you asking these questions, what are the data for?What is in it for me?What happens to the data (including who has access to it)?These concerns were explored further in Stage 3 online surveys to inform implications for the introduction wording, question order, and discussion of the appropriate mechanism for collection.Stage 3: Online surveysSurvey responses were received from a total of 533 NSW public sector employees  from 41 agencies across 10 public sector clusters . Here, we summarise the results for D and E questions referring to survey questions by number . The perA higher percentage of people responded to D1 (26.2%) and D2 (30.5%) in a way that indicated disability than those who answered “yes” to Q11 (16.6% for Survey 1 and 26.8% for Survey 2) . While dBoth D1 and D2 “picked up” approximately 85% of people explicitly stating that they have a disability in response to Q11  .Significantly, D1 and D2, while showing a strong relationship with Q11, “captured” more people who were dealing with potential difficulties in their daily lives via technologies and other strategies.Of those who were not “picked up” by D1 , only 3.5% (8 in 231) stated later that they have a disability (in response to Q11) ) .Analysis of survey responses to Q1–Q11 indicated that both D questions (D1 and D2) tested are inclusive indicators of “disability”, and lead to the inclusion of more people than the question “do you have a disability?” (Q11):Box 2I would answer yes to D1 and no to D2 because I have mobility issues due to arthritis but don’t consider I have a disability. But am impaired somewhat with mobility.I technically have a disability  but have not disclosed this in past job applications. The questions being phrased in the more open way they are above would encourage me to respond more accurately.Overall, D1 was considered slightly easier to understand than D2; 93% of respondents reported that D1 was “easy” to understand, compared to 91% for D2 (Q6); 12.5% felt that D1 had words that needed explanation, compared to 15.5% for D2 (Q7).Survey respondents were comparatively more “comfortable” answering D1 (in response to Q8)—there was little difference in Survey 1 responses; difference was more marked in Survey 2, with 63% in favour of D1 and 37% in favour of D2.The examples provided in D1 were appreciated by respondents to both surveys . Examples of everyday life areas were considered helpful by 68% of respondents to Survey 1 and 69% to Survey 2. Examples of long-term health conditions and impairments were considered helpful by 65% of respondents to Survey 1 and 60% to Survey 2.Of the two D questions, it was concluded that D1 should serve as the basis for a final recommended D question for consideration and development by the NSW PSC. Descriptive statistics illustrated that :Overall,“Impairment” was mentioned as a word needing explanation . There were few negative comments on impairment (two negative comments in response to Q7 made by people reporting disability in terms of D1 or Q11); the focus group discussions and the great majority of responses to the online survey did not flag any concern. Impairment is a term widely used in the disability field, including in the UNCRPD and ICF. Use of only “long-term health condition” in its place was not supported by focus group comments, which indicated a preference for using both terms; the examples of “conditions and impairments” listed in D1 (favoured by survey respondents) do contain impairments. Use of impairment categories  from D2 was not recommended; a number of text comments from the survey sought explanation of the bracketed words.The use of the word “disability” in the questions appears to exclude some people from responding, e.g., those with functioning difficulties arising from long term health conditions; this is the balance of evidence from the online survey statistics, text responses, and focus group results. “Disability” would perhaps better be used in the introduction to the question.The word “participation” was well received by participants in focus groups and in the online survey; it was not included in D1 in the survey but should be in further development of D1.The text comments offered throughout the survey help explain the statistics from the online surveys. These comments generally supported the conclusions of the statistical analysis, namely, to develop D1 into a recommended D question:Both privacy and use of the data appeared significant concerns in text responses to the introduction and requests for “any other comments”, reinforcing focus group views. People reported lacking knowledge of and confidence in how data are used.The great majority of survey respondents (95% or more) found all four E questions “very easy”, “easy”, or “somewhat easy” to understand (in response to Q14 and Q18). A correspondingly high proportion said no further words needed explanation ). A higher proportion of respondents indicated that words needed explanation in EN2 (11.4%) and EP2 (10.3%) compared to EN1 (7.1%) and EP1 (6.0%) (in response to Q15 and Q20) .Respondents demonstrated no difficulty in responding across all five areas of the ICF environmental factors, and in differentiating present needs and needs met. The questions have the capacity to yield interesting information .There was greater comfort answering EN1 than EN2 (in response to Q16)—59% of people in Survey 1 were more comfortable answering EN1; preferences were evenly split in Survey 2, with 51% preferring EN1 and 49% preferring EN2. The word “improvement” (in EN1) appeared to be favoured over “adjustment” (in EN2). Similarly, EP1 was preferred to EP2 (in response to Q21).A higher percentage of people indicated that “improvements” are needed in all five aspects of the environment in response to EN1 compared with those who indicated that “adjustments” are needed in response to EN2 (Q13). Correspondingly, a lower percentage of people indicated “no improvement needed” (40.6%) in response to EN1 compared with those who indicated “no adjustment needed” (56.4%) in response to EN2. A similar but less marked pattern was seen for EP1 and EP2 (Q.18)—57% in Survey 1 reported no past improvements, and 65% in Survey 2 reported no past adjustments. The results could reflect a difference between the samples, or that EN1 and EP1 are open to wider interpretation.On the basis of analysis of survey responses to Q13–Q21, we concluded that, of the four E questions , EN1 and EP1 should serve as the basis for two final recommended E questions for consideration and further development by the PSC :The greaGenerally, people preferred simpler wording, without jargon and need for further explanation. Comments (in response to Q15 and Q20) reinforced preferences for the term “improvement” rather than “adjustment”, which was frequently mentioned as a word needing explanation. Other problematic terms reported include “human-made”, “enable”, and “colleagues”.There was a suggestion from Survey 1 to simplify “what aspects of your work environment” to “at work” ... “enable you to participate fully and effectively”.From Survey 2, suggestions included the need for further explanation or alternative terms such as “adjustments”, “EN2 asks me what help I need”, “EN1 feels like it is seeking a criticism about my workplace”, “EN2 reads like we all need adjustments, and ‘what adjustments have you and your employer made’ may be more positive”.The relatively small number of text comments about E questions (24 in each survey) generally supported the conclusion of the statistical analysis—namely, to develop EN1 and EP1 into two recommended E questions, with attention to suggestions for improvement. Free text comments from survey respondents, with feedback from focus groups, provided guidance for amending the questions, and could also be used to improve layout:Overall, the free text responses about both the D and E questions, briefly illustrated in this paper, provided rich material for question redevelopment.With the aim of improving the WFP questions and data, the research developed a new set of questions  related Questions are inclusive: The new questions bring into scope more people than the question “do you have a disability?”—for example, people with long-term health conditions who may not identify with disability, as well as people using technologies and other strategies to manage difficulties in their daily life.Comparable to NSW population data: The new questions use key concepts used in other data collection instruments (as well as key policy instruments), thus promoting comparability with the NSW population and labour force data.Clarity and meaning: The new questions were preferred to the alternatives as they were considered easier to understand.Comfort in answering: The new questions were preferred to the alternatives as more employees were comfortable answering them.The new questions performed well against the objectives of the project:Following all three stages of the research, including analysis of statistical and text results of the online survey, which informed further refinement of the questions, There was strong support for lists of examples: of health conditions and impairments that may interact with the environment to create the experience of disability, as well as for areas of the environment involved in this interaction. Example lists used were based (respectively) on the list used by the ABS in the SDAC and the environmental factors classification of the ICF; the environmental lists and examples were seen as easy to understand and to require little explanation.Box 3Question D1:participating), related to a long-term health condition or impairment, in any of the following:Social and community life .Work, education or training (including paid or voluntary work).Mobility .Self-care .Home life .Daily organisation .Communication .Learning .Relationships .In your everyday life, do you experience difficulty .Attitudes .Services, systems, and policies .Products and technology .Natural environment and human-made changes to environment Do aspects of your work environment need to be improved to enable you to participate fully and effectively at work? :No improvements needed.EP1 similar to EN1 but referring to the past i.e., what has been done:Have aspects of your work environment been improved to enable you to participate fully and effectively at work?Further analysis of text responses to the online survey and of notes taken during focus group discussions could lead to even further refinement of words and examples in D, along with further plain English editing.Further discussions could be undertaken with agencies with interest in disability data, including the Australian Human Rights Commission. Further testing of the questions in another English-speaking country with similar national data, or use of the process described here to develop relevant national questions, may provide useful insights and comparisons in similar work-related contexts.The strong association between the new disability questions, about difficulties participating in everyday life, and the question “Do you have a disability?” (Q11), is interesting and perhaps reassuring. Nevertheless, some analysis suggests areas of future research. Notably, D1 and D2, while showing strong relationships with Q11, “captured” more people who were dealing with potential difficulties in their daily life using technologies and other strategies. This finding reflects views expressed in the focus groups that the existing D question in the WFP (similar to Q11) may lead to self-exclusion. For example, as illustrated by the focus group and survey comments, people with difficulties related to long term health conditions or people whose difficulties are mitigated by technology or environmental facilitators may have varying views of disability and may not identify or declare they have a disability.The apparently greater inclusivity of the new questions resonates with results from related research in a vastly different setting. Disability identification in refugee situations, for the purposes of offering services and determining and meeting needs, was found to be best done using “functionality-based questions in line with international standards” along with staff training to enable “greater sensitivity to the many different ways in which disability can manifest” .Communication at various points will be an essential part of improving data. Communication mayhave various purposes and messages—communication about system changes; reminders about the need for updating data, the value of the data, and of participation in providing it; explanation of the importance and purpose of the questions; and accurate assurances about privacy and confidentiality; anduse various avenues—announcements, publications, presentations, and routine communication, e.g., in forms and databases including through explanation of and introduction to the questions.A communication strategy could be devised on the basis of the findings of this project and decisions made about implementation in order to support the chosen paths forward on data collections relating to disability in the NSW public sector.Further high-level consideration by the PSC about the purpose and use of the disability (D) and environment (E) questions is essential in order to establish the basic “why, who, when” purposes and processes. There was strong comment in both the focus groups and online survey, revealing distrust among NSW public sector employees concerning the purpose of the D question in particular and about data confidentiality.The most appropriate data collection vehicle to gather information on disability and accessibility requires consideration. Some Australian government jurisdictions collect their disability data through HR systems and others through sample employee surveys , possibly similar to other countries. There are advantages and disadvantages to both methods .The PMES is anonymised and online, and not linked to HR systems. The PSC has control of the questions and is the sole data custodian. However, because the recommended questions are long (relative to others in that survey), so as to reflect the complexity of disability, there are advantages to using them in a context where this complexity can be explored. Therefore, the WFP collection, which draws information from HR systems, may remain the better approach, as it allows the accumulation of more in-depth data over time; the WFP collection was the focus intended at the start of this research. The questions could be asked during HR processes and stored in HR systems; if so, the purpose needs to be clear and assurances about use and privacy provided and demonstrated. While the purposes may include monitoring disability employment rates, locating the data with HR creates the capacity to cross-tabulate disability data with other relevant HR data  and statistically monitor change over time.Trust and comfort in reporting may also be influenced by the inclusiveness of the workplace, where employees feel “safe” to share their personal information. Both elements—technical and cultural—are important in developing a better picture of workplace inclusion of people with disability—having appropriate survey questions, ethical data storage and use practices, and an environment where employees feel their information is respected and acted on constructively.The links between the D and E questions also need to be decided. It has been assumed that the D question comes first and acts as a filter to direct people to the E questions. An alternative could be to use the E question as the first question, and then ask for explanation of why environmental change is needed, even perhaps using all “diversity” questions as possible reasons. This approach has not yet been tested and has policy implications. In favour of this re-ordering is the finding that the E questions did not elicit the types of free-text comments made about the D questions. It was clearer why E questions were being asked and what actions might be taken on the basis of answers. However, there remains a question about timing; for example, people may find it hard to comment soon after recruitment on what environmental improvements they need.The results of this project thus raise wider questions of data collection strategy. One option is to re-think the use of two questions, on disability and environment, as part of an overall strategy to improve understanding of disability and changes needed in the workforce environment. The questions could be used to monitor changes in the environment as well as in the representation of people with disability in the workforce.The OECD noted, in contrasting disability policy reform with the lack of improvement in employment rates, “disability system reform is a huge task, for several reasons” (p. 93 ). Many mIn the public sector, creating a succinct identifier for disability in administrative systems is a key challenge for public policy design and monitoring. This requires concise methods of identifying people with disability within systems, producing data comparable with population data to gauge accessibility and equity. This paper focussed on efforts to improve data in the service of evidence-based policy. The project described here formed part of a broader program of work to improve interventions that build inclusive work environments and enable people with disability to have positive work experiences in and contribute to the NSW public sector.We aimed to create disability-related questions of value to the purposes of an Australian state and contribute to literature on parsimonious and respectful disability identification for wider application. Both these aims were achieved. Recommendations for new disability-related questions and possible new data collection and related communication processes are under active consideration by the leading state authority, as are the additional factors identified during the collaborative research relating to the design of and communications about administrative data collections. More broadly, this research contributes methodology and findings relevant not only in the Australian public sector, but in other countries with good quality national population data with which administrative data can be compared.


Fibrosis is the result of chronic inflammation and is known to pathologically occur in many organs and systems. Pirfenidone (PFD) is an anti-fibrotic known for its use in idiopathic pulmonary fibrosis (IPF). In addition to being an anti-fibrotic, it acts as an anti-inflammatory and antioxidant as well. There have been studies on PFD in other diseases, some clinical and others preclinical. We have compiled and reviewed them to highlight just how widespread PFD use could be. Among many benefits of PFD in IPF, PFD has effectively improved patients' survival in those who had an acute exacerbation of IPF and has reduced respiratory-related hospitalization, among few others. PFD also has shown an improvement in vital capacity in patients with chronic hypersensitive pneumonitis. Also, it has demonstrated anti-fibrotic effects in systemic sclerosis-associated interstitial lung disease. In other diseases outside the lungs, PFD has reversed insulin resistance and proven to be effective in non-alcoholic steatohepatitis (NASH). It has prevented blindness post-alkali injury to the eye and has proven to decrease the proliferation of mesothelioma cells, just to name a few. This review encourages further research in connection with PFD and its use in other diseases and PFD pros in IPF. Fibrosis is scarring tissue and occurs when excess extracellular matrix material is replaced by collagen and fibronectin in response to cellular damage. Fibroblasts are the producers of a variety of substances found in the extracellular matrix. When these cells transform via a range of signaling programs, they differentiate into many types of cells. Myofibroblasts are one of its major phenotypes. They play a significant role in excessively synthesizing and secreting the extracellular matrix. They also hold resistance against apoptosis. These cells are susceptible to chemokines, cytokines, and growth factors . These cPirfenidone (PFD) is an anti-fibrotic drug known to act on multiple fibrogenic pathways to reduce fibrosis in IPF of the lungs. It downregulates the production of growth factors . It alsoAside from IPF, there are additional diseases of the lungs and other organs that lead to fibrosis. Fibrosis is the result of multiple common steps in such conditions, and PFD targets such pathways. Hence more positive clinical evidence and trials are needed on PFD's usage in different diseases that might improve the quality of life and mortality if used in patients. A random double-blind control study showed PFD to be a promising drug for individuals with overt diabetic nephropathy . AnotherPFD is a drug that is already approved for IPF. However, much has to be learned about PFD in the real-world population concerning IPF's role in reducing respiratory-related hospitalizations and efficacy in advanced IPF, among few others. Also, only a few studies have explored its use in other fibrotic diseases. In this article, we will review some of the studies about PFD in IPF. Also, we will see PFD's use in other diseases based on the studies that have been done. We intend to encourage scientists to conduct further trials that would help prevent fibrosis progression and, if possible, to reverse it in phenomena where it is known to occur.Pirfenidone in idiopathic pulmonary fibrosis TGF-β is an important cytokine that facilitates fibrosis. It induces alpha-smooth muscle actin (α-SMA), pro-collagen (Col)-I messenger RNA (mRNA), and protein levels, all of which are attenuated by PFD. Also, TGF-β-induced phosphorylation of Smad3, p38, and a serine/threonine-specific protein kinase (AKT) are inhibited . AdditioMost of the patients enrolled in one study on PFD and its effect on respiratory-related hospitalization were men and white. The PFD group had significantly lower respiratory-related hospitalization compared to the placebo. A few reasons for PFD reducing respiratory-related hospitalization could be decreasing acute IPF exacerbation or collateral damage by reducing disease severity. We don't know what kind of respiratory-related hospitalization had been influenced by PFD. Also, it is a post hoc analysis, so data gathered from such analysis should be carefully viewed . AnotherAnother study considered many IPF disease progression events such as a relative decline in % forced vital capacity (FVC) > 10%, absolute decline in six-min walk distance >50m, respiratory-related hospitalization, and death. Patients under PFD treatment were less likely to experience multiple disease progression events, and the result was significant compared to placebo. But again, patients were included from the ASCEND and CAPACITY trials; hence most patients were men and mostly white. Also, it was a post hoc analysis . In anotAn open-label extension study (RECAP) took into account the patients who completed the CAPACITY and ASCEND trials to know PFD's effect on long-term safety. However, there were strict inclusion-exclusion criteria for patient selection in the clinical trials. So, even though the RECAP study findings were consistent with PFD's already known safety profile, they could not be applied to a broader population . In contPirfenidone in other diseasesMalignant Mesothelioma, Dupuytren's Disease, and Acute Lung InjuryIn a study done on PFD in malignant mesothelioma, it was shown that PFD reduced the TGF-β-induced extracellular-signal-regulated kinase (ERK) and serine/threonine-specific protein kinase (AKT) pathways . Not onlNonalcoholic Steatohepatitis and Acute PancreatitisA study on PFD in non-alcoholic steatohepatitis (NASH) showed that PFD restricted and reversed the steatosis. Diet was used to induce NASH in mice. Many mechanisms were involved through which PFD had its reversing effect. It affected macrophages in a way that T-cell numbers were reduced. PFD upregulated the antioxidant genes, and genes pertaining to the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase complex were downregulated. That way, the oxidant stress was limited. The oxidation of fatty acids was increased, and lipogenesis was decreased. The expression of the inflammatory gene was reduced as well . AnotherSystemic SclerosisSystemic sclerosis affects several organs, and there is fibrosis of the lungs' interstitium as a part of the disease. A multinational study was done on systemic sclerosis-interstitial lung disease (SSc-ILD) wherein patients were recruited from across three countries . Sixty-tWound Healing and Existing ScarsAnother study researched culturing adult human dermal fibroblasts treated with TGF-β1. Consequently, they differentiated into myofibroblasts. The goal of the study was to test the effect of PFD on differentiated myofibroblasts. This was important because if PFD can act on differentiated myofibroblasts, it could be used on existing scars and for healing wounds. Results were such that the expression of genes that promote fibrosis was down, mainly affecting the expression of alpha-smooth muscle actin. Also, the contractile force was reduced. The findings are promising, but still, it is an in-vitro study . AngiogeEye PathologiesConsidering PFD's effect on eye pathologies, one study also explored its impact on corneal inflammation post-alkali burn injury in rabbits. PFD lowered IL-β1 expression, an inflammatory cytokine, and TGF-β1, a pro-fibrotic growth factor . ConsequTransplantation A study was done to see the effect of PFD on subsets of T cells with a focus on fighting allograft rejection. Production of cytokines that were associated with Th1 and Th2 was inhibited. Regulatory T cells (Tregs) didn't seem to be affected by PFD. PFD had more impact on CD4+ T cells than CD8+ T cells as observed in vitro; however, in an in vivo model, there was inhibition of both CD4+ and CD8+ cells that was observed. An added effect on the inhibition of CD4+ and CD8+ T cells' proliferation was seen when PFD was used with low-dose rapamycin. The study shows that PFD could potentially be used to fight chronic rejection . A retroLimitationsAnimal studies and in-vitro studies were included, among others, in this review. Also, few studies date back more than five years. There were studies discussed under PFD in the IPF section, wherein the population was mainly men and white, and the sample size was small, limiting generalizability. The study population in those studies were from the ASCEND and CAPACITY trials, and the patient selection was through strict inclusion-exclusion criteria. A retrospective study didn't follow those strict inclusion-exclusion criteria; however, the sample size was small. There were no studies as such that could be generalized as per the real-world population.Several benefits of PDF's are evident in IPF based on the studies reviewed. It reduced the respiratory-related hospitalization over one year in IPF, improved the survival benefit in patients admitted due to acute exacerbation of IPF, and was shown effective in more advanced IPF, among other benefits. All these studies had a limited sample size, and many of them had their study population from ASCEND and CAPACITY trials (mostly men and white). So, studies on PFD in IPF that can be generalized as per the real-world population are needed. PFD also seems promising in several other diseases where it would provide its anti-fibrotic and anti-inflammatory benefits. It reduced the accumulation and oxidation of lipids in NASH, reduced the proliferation of malignant mesothelioma cells, and inhibited systemic sclerosis pathways that led to fibrosis, among other benefits. Although many studies were preclinical, the results were outstanding. So, PFD has shown effectiveness in many aspects of IPF. Not only that but also it's been useful in other diseases as per the studies. Despite the limitations, the findings of studies tell us that PFD has a vast scope, and future studies in connection with it would change the outcome in many diseases.