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The purpose of this paper is to demonstrate the simplicity and versatility of micro‐cantilever based sensors and to present the influence of added mass and stress on the frequency response of the sensor in order to determine the most suitable sensing domain for a given application.

The frequency response of micro‐cantilevers depends not only on the applied mass and surface stress, but also on the mass position. An interpretation of the theoretical frequency results of the 1st and 2nd natural frequencies, for added mass, identifies a nodal point for the 2nd natural frequency which demonstrates mass invariance. Hence, at this nodal point, the frequency response remains constant regardless of mass and may be used for identifying purely induced surface stress influences on the micro‐cantilever's dynamic response. The Rayleigh‐Ritz energy method is used for the theoretical analysis. Theoretical results are compared with experimental results.

A graph of the 2nd natural frequency of micro‐cantilevers with added mass demonstrates the variability of the frequency with mass position on the micro‐cantilever. Of particular interest is the nodal point at which mass independence is revealed. This nodal point may be exploited to investigate purely stress‐related influences on the dynamic characteristics of micro‐cantilever sensors, thereby eliminating such effects as reactant evaporation from the micro‐cantilever sensor surface. In this regard, the nodal point of the 2nd natural frequency response is used to decouple mass‐stress influences.

Owing to the micro‐scale size of the micro‐cantilevers, it may not be possible to apply mass or stress directly at the nodal point and to concentrate its influence there. Hence, a certain amount of influence due to mass‐stress coupling may remain in the frequency responses observed.

Silicon micro‐cantilevers can be easily shaped and sensitized to a variety of influences. These qualities are highly regarded for sensor applications. The work presented herein, contributes to the optimization of micro‐cantilever sensors' dynamic response as a function of mass and surface stress influences. The main criterion for choosing one or the other is based on the time for the surface reaction to take place between the sensing material and the target material. The results presented contribute to the performance optimization of micro‐cantilever based medical and bio‐sensors.

Surface stress effects are generally of much smaller magnitude than mass influences; hence, through an investigation of the stress effects at the nodal point of the 2nd natural frequency it is possible to eliminate the mass influence completely. At this position mass and stress influences are decoupled and the sensor response can be uniquely quantified as a function of the applied stress. This is important for bio‐medical and health monitoring applications in which changes to the applied mass or surface stress on a micro‐cantilever sensor, may be readily observed through changes to the natural frequency response of the micro‐cantilever.

This paper seeks to establish an analytical reference model in order to optimize the frequency response of MEMS cantilever structures using cutouts.

Presented in this work is a method to tune the frequency response of MEMS cantilevers by using single cutouts of various sizes. From an interpretation of the analytical results, mass and stiffness domains are defined as a function of the cutout position on the cantilever. In this regard, the elastic properties of the MEMS cantilever can be trimmed through mechanical tuning by a single cutout incorporated into the device geometry. The Rayleigh‐Ritz energy method is used for the modeling. Analytical results are compared with FEM and experimental results.

The eigenvalues are dependent on the position and size of the cutout. Hence, the frequency response of the cantilever can be tuned and optimized through this approach.

MEMS microsystems are sensitive to microfabrication limitations especially at the boundary support of suspended structures such as microcantilevers.

MEMS cantilevers are resistant to low level vibrations due to their low inertia and the elastic properties of the silicon material. For sensor applications these qualities are highly regarded and explored. This analysis will contribute to the performance optimization of atomic force microscope (AFM) probes and micromechanical resonators.

A method to tune, with cutouts, the frequency response of microcantilevers is proposed. The data can provide insight into the performance optimization of micromechanical resonators through mass reduction. For industrial applications requiring optimized responses the cutouts can be incorporated into microcantilevers through focused ion beam (FIB) machining or laser drilling, for example.

To establish an accurate and sensitive method to characterize the moisture content of a particular environment.

This paper proposes a relatively simple humidity sensor design consisting of electrodes on a suitable substrate coated with a polyimide material. The changes in relative humidity are denoted by a corresponding change in the polyimide material's electrical resistance profile. The design proposed in this work can be microfabricated and integrated with electronic circuitry. This sensor can be fabricated on alumina or silicon substrates. The electrode material can be made up of nickel, gold or aluminum and the thickness of the electrodes ranges typically between 0.2 and 0.3 μm. The sensor consists of an active sensing layer on top of a set of electrodes. The design of the electrodes can be configured for both resistive and capacitive sensing.

The polyimide material's ohmic resistance changes significantly with humidity variations. Changes in resistance as large as 4‐6 orders of magnitude are attainable over the entire operational humidity range.

As the sensitivity varies non‐linearly with the humidity, the measurement has to be carried out over a very wide range in order to calibrate the sensor. The sensitivity and output range of the sensor can be easily controlled by changing the electrode spacing or geometry.

The control of humidity is important in many applications ranging from bio‐medical to space exploration.

A simple, easy to fabricate and measure, and low cost resistive‐type humidity sensor was developed. The realized sensor is suitable for integrating with microfabrication. Hence, multiple sensors of varying sensitivities and output ranges could be integrated on the same chip. Over the last few years, newly emerging micro‐electro‐mechanical‐systems technology and micro‐fabrication techniques have gained popularity and importance in the miniaturization of a variety of sensors and actuators.

It is currently difficult to measure temperature and pressure in harsh environments. Such measurements are limited by either the ability of the sensing element or the associated electrical wiring to withstand the operating environment. This is unfortunate as temperature and pressure are important measurands in various engineering structures as they provide critical information on the operating condition of the structure. Hence, there is a need to address this shortcoming. Such a sensor in place would enhance the operating efficiency thereby reducing the pollution burden and its impact on the environment. The purpose of this paper is to present theoretical and preliminary experimental results for a co‐integrated pressure and temperature sensor for harsh environments.

This work describes a co‐integrated pressure‐temperature wireless sensing scheme. The approach presented herein provides the possibility of measuring dynamic pressure and temperature within an enclosed volume using acoustic signals. Resonance tube physics is exploited for the temperature sensing. A microphone is used to obtain the acoustic signal whose frequency is a function of the temperature and the tube geometry.

The dynamic pressure is measured from the calibrated amplitude of the pressure wave signal measured by the microphone. The temperature can be measured through the shift of the standing wave frequency with a resolution of <1°C. The resonance tube can be fabricated using any material that resists harsh environments. The geometry of the tube can be tailored for any specific frequency range, as the application warrants. Also, this provides a means for accurate temperature compensation of pressure sensor data from high temperature environments. A Matlab/Simulink model is developed and presented for the acquisition of acoustic signals through the wall of an enclosed volume. For these applications the standing wave signal transmitted through the enclosure wall becomes a function of the wall material and wall thickness. Preliminary experimental results are presented in which a DC fan is used for generating the dynamic pressure in a varying temperature environment.

The major issue is the separation of the noise from the signal. As various applications yield specific signal noise, the problem needs detailed data to be addressed.

Temperature and dynamic pressure could be recorded/monitored in very harsh environment conditions such as chemical reactors.

This work demonstrates the possibility of employing a co‐integrated acoustic sensing scheme in which both pressure and temperature are measured simultaneously with a sole sensor. The major advantage with acoustic sensing is the wireless transmission of data. This allows for non‐invasive measurement from within enclosed systems. Direct real‐time temperature compensation is possible that does not require any compensation circuitry. Hence, pressure and temperature data may be obtained from caustic operating environments whose access is otherwise not feasible.

Business creation is an important measure of real economic activity as it shows the dynamics with which new firms are born, create jobs, move their capital, innovate and compete with old firms. In this sense, this paper aims to analyze the short-term impact of the lockdown policies implemented to stop the spread of the COVID-19 on the creation of new formal firms in Ecuador.

This paper uses a regression discontinuity in time (RDiT) design jointly with official administrative real-time data. This data is collected by the supervisory and regulatory institution of formal companies in Ecuador. The authors use real-time data from January 13, 2020, to May 15, 2020. This period allows to use the President’s order of effective lockdown on March 16, 2020, as the exogenous event. This gives 43 working days on each side of the cutoff date on the baseline model.

The authors find: an overall large drop in the creation of new formal firms (−73%) and a decrease in the total amount of initial capital coming from the new formal firms (−40%). Additionally, the results suggest that the negative impact of the COVID-19 lockdown on the creation of new formal firms seems not to decrease in the short term. The main conclusion is that lockdown policies have a negative impact on firm creation, a result that is of high policy relevance and can be a tool to design business attraction policies.

The analysis is carried out in a short period because on May18, 2020, a new policy was applied in Ecuador that allowed firms to be created more quickly, with 1 USD of capital, and 1 shareholder, among other benefits, and this may affect the outcomes analyzed in this document, so extending the analysis of the impact of the lockdown to a longer period could result in biased results due to this policy. Additionally, studying daily sales would be of the utmost importance; however, these data are not found in the database of the supervising institution.

This study contributes to the empirical literature and the policy debate in various aspects. First, it is important to generate facilities for the creation of new formal firms, from the reduction of days it takes to create one (using technology as a support in this matter) to the decrease of the minimum capital to formalize a company. Second, improve the business conditions of the new formal firms that were born during the pandemic, but also that these conditions create stimulus for the creation of new companies. Third, the authors show that induced-lockdown policies have a negative impact on the creation of new formal firms and the total amount of initial capital from new formal firms; this effect could be a full-blown recession if governments do not apply mechanisms to revert this situation that could be a drag on the economy.

This paper opens the debate on the effects of the COVID-19 lockdown on the creation of new formal firms; therefore, future research could study the impact in a broader time window to analyze medium and long-run effects, but also in different economic sectors and in the effects on firm bankruptcy, which added to an analysis of job loss, will show a total effect of damage in the economy.

The purpose of this paper is to offer a concise survey and comparison of Italian accounting research and academic publications during the second half of the 20th century.

The paper discusses the special relation between economia aziendale (business and public economics) and ragioneria (accounting) in Italy. The subsequent discussion on “financial accounting” includes a sub‐section on income‐orientation (vs capital‐orientation), especially important in Italy during this period, and the present crisis of economia aziendale as affecting ragioneria, contributions by major Italian accountants of the period (above all, Onida and Amaduzzi) are discussed. After a section on “cost and managerial accounting” (of less significance in Italy than financial accounting), and a look at “novel accounting trends”, the paper closes with a discussion of some representative historical studies of the period.

The paper reveals the changing international position of Italian accounting research.

The paper is limited by selecting the most prominent and relevant contributions among a host of pertinent publications.

In contrast to previous research, the paper offers an integrated survey of major Italian accounting publications of the entire second half of the 20th century.

This paper aims to investigate how narrative is constructed to create connections with fat readers, how books function to envision spaces of fat liberation for young readers and to highlight the incredible importance of providing bigger mirrors (Bishop, 1990) for fat representation in children’s literature.

This paper analyzes and reflects on two texts that contain counternarratives of fatness: The (Other) F Word: A celebration of the fat and fierce edited by Angie Manfredi (2019) and Big by Vashti Harrison (2023) to interrogate how these two narratives intentionally disrupt anti-fat bias.

Body size and fatness are identities that need to be included in diversity efforts within education. Books like The (Other) F Word: A celebration of the fat and fierce (Manfredi, 2019) and Big (Harrison, 2023) offer positive representations of fatness, disrupt biases around body size and provide spaces that allow fat students to find joy, hope, connection and, more than anything, imagine a way toward liberation.

This paper highlights the need to include more narratives of positive fat representation within children’s literature and calls for educators to interrogate their own anti-fat biases and practices.

There is a lack of research on fat representation specifically within children and young adult literature. This paper provides an analysis of two pieces of literature with fat representation that brings attention to the need for this type of future research.

Despite growing scholarly interest in academic entrepreneurship (AE) few studies have examined its non-commercial aspects and how it contributes to meeting grand societal challenges. One explanation for this may be the continuing focus of AE on intellectual property commercialization. This paper aims to address this knowledge gap by uncovering how universities can contribute to promoting non-commercial forms of AE.

This paper uses the human capital theoretical lens to make its argument and applies it to data obtained from exploratory qualitative research (55 semi-structured interviews and nine focus groups) in the developing countries of Bolivia, Colombia and Ecuador.

Universities can promote different forms of non-commercial AE even in the absence of sophisticated resources for innovation, through the stimulation of the specific human capital of the university community resulting from activities where they help others.

This paper proposes a general framework for advancing theory development in AE and its non-commercial forms, based on data obtained in uncharted territories for AE.

In the accounting field, sustainability accounting (SA) has evolved as a valuable tool that links improvements in environmental, social and governance issues to financial performance. This study aims to examine the structure and evolution of SA research, map the state of knowledge and analyse the literature trends and gaps.

The study adopts a bibliometric review technique with data sourced from the Scopus database. A total of 7,049 extant literature spanning from 1982 to 2022 was analysed using the VOSviewer software.

The authors find a significant growth in the number of publications on SA research, primarily driven by collaboration among researchers from Europe and America. The analysis highlights emerging themes, structure and discusses in detail the changing phases of SA research over the past four decades while highlighting key events that have impacted the development of SA research. Furthermore, the dominant theories used by extant studies are discussed and potential avenues for future research are provided. The authors draw the attention of the research community to the dominant authors, the most cited articles, prominent publication outlets and countries advancing research in this field.

This study advances knowledge on SA research by providing a retrospective assessment of the state of knowledge in the field while highlighting avenues for future research.