This study presents the development and characterization of a novel transferable capacitive sensor based on poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) as the primary electrode material. The electrodes were fabricated using an in-situ deposition technique that leverages the self-adhesive, flexible, and highly conductive properties of PEDOT:PSS to enable direct and stable contact with diverse surfaces for continuous, non-invasive hydration measurement. To evaluate their performance, PEDOT:PSS-based sensors were systematically compared with alternative electrode materials—including graphite, silver, gold, and indium tin oxide (ITO)—under controlled humidity conditions. A key innovation in this work is the integration of an ultra-low-cost impedance measurement system, enabling scalable and cost-effective capacitance-based hydration sensing. The study explores sensor fabrication, material characterization, and equivalent circuit modeling, quantifying the contributions of interfacial capacitance and dielectric properties. The results show that PEDOT:PSS electrodes exhibit enhanced hydration sensitivity at the electrode-dielectric interface, confirming that hydration-driven charge transport mechanisms dominate its capacitive response. This unique property allows PEDOT:PSS to detect subtle hydration fluctuations more effectively than conventional electrode materials, making it particularly well-suited for real-time monitoring in wearable electronics, biomedical diagnostics, and environmental sensing. Although physiological validation remains an essential next step, these findings establish a foundation for integrating PEDOT:PSS-based capacitive sensors into bioelectronics, flexible sensing platforms, and environmental monitoring technologies, facilitating the development of cost-effective, non-invasive hydration sensors across multiple fields.

Monte-Carlo simulations were used to describe the interactions between cellular automata, socio-economic ‘agents’, in society. In a first simulation we repeat work in literature of a system of independent agents. We repeat the finding that the strongest agent will confiscate all wealth. In a second simulation we show how agents can prevent against such theft, or steal better, by joining forces. So-called join-believe-fight (joining, believing unquestionably in the narrative of the faction, and fighting other factions). We now take cooperations between factions of joined agents into account. The final outcome is that society obliterates libertarians (those that are reluctant to join forces) and winds up in a situation in which all surviving agents are joined in a single faction. However, it is reasoned that then fights within this single faction will start, since this end situation resembles the starting point of entire society; the single faction has become entire society and the game recommences. It is a snake that bites its own tail and goes around forever attacking.

In this work, the transient techniques for disordered organic thin film transistors are analyzed. A special emphasis is made on stress. Stress in this work is the continuous increase of the threshold voltage upon applying a gate bias. In this work a new stress evaluation method is presented that allows for a rapid determination of stress. Moreover, a figure-of-merit is proposed that can be applied to non-exponential transients, including those of stressing. The transients are compared to the empirical transient functions reported in literature that range from power-law to stretched exponential and logarithmic.

We study the concepts of residence time vs. adjustment time time for carbon dioxide in the atmosphere. The system is analyzed with a two-box first-order model. Using this model, we reach three important conclusions: (1) The adjustment time is never larger than the residence time and can, thus, not be longer than about 5 years. (2) The idea of the atmosphere being stable at 280 ppm in pre-industrial times is untenable. (3) Nearly 90% of all anthropogenic carbon dioxide has already been removed from the atmosphere.

An ultra-low-cost RCL meter, aimed at IoT applications, was developed, and was used to measure electrical components based on standard techniques without the need of additional electronics beyond the AVR® micro-controller hardware itself and high-level routines. The models and pseudo-routines required to measure admittance parameters are described, and a benchmark between the ATmega328P and ATmega32U4 AVR® micro-controllers was performed to validate the resistance and capacitance measurements. Both ATmega328P and ATmega32U4 micro-controllers could measure isolated resistances from 0.5 Ω to 80 MΩ and capacitances from 100 fF to 4.7 mF. Inductance measurements are estimated at between 0.2 mH to 1.5 H. The accuracy and range of the measurements of series and parallel RC networks are demonstrated. The relative accuracy (ar) and relative precision (pr) of the measurements were quantified. For the resistance measurements, typically ar, pr < 10% in the interval 100 Ω–100 MΩ. For the capacitance, measured in one of the modes (fast mode), ar < 20% and pr < 5% in the range 100 fF–10 nF, while for the other mode (transient mode), typically ar < 20% in the range 10 nF–10 mF and pr < 5% for 100 pF–10 mF. ar falls below 5% in some sub-ranges. The combination of the two capacitance modes allows for measurements in the range 100 fF–10 mF (11 orders of magnitude) with ar < 20%. Possible applications include the sensing of impedimetric sensor arrays targeted for wearable and in-body bioelectronics, smart agriculture, and smart cities, while complying with small form factor and low cost.

The effects of the Covid-19 pandemic and governmental countermeasures are described in this work by putting it in the framework of the Energy Theory of Value. It is found that the downturn in economy is not accompanied by an equal downturn in energy consumption nor of carbon emissions. Moreover, not even the empirical fifth-power law linking the former two is any longer sustained, more so proving the state of virtualization of our economy (disconnecting it from a physical reality). It is also found that the reduction of carbon emissions had no impact on the dynamics of carbon in the atmosphere, which goes on business as usual. All these results undermine the planned policies of the world agenda.

We report on the development of an electrical characterization admittance spectroscopy equipment and method based on an off-the-shelf lock-in detector that is cheap and yet highly sensitive. It is concluded that a contacted constant-pressure electrode configuration is preferable. It was further determined that the temperature does not have great impact in the measured values, but relative humidity of air can be important, especially in the constant-gap electrode configuration. In-situ measurements are difficult since the coupling of the plant with the environment is of high importance. Another aspect is the cables; they are important in that they have to be terminated by their characteristic impedance (50 Ω in our case) to avoid reflections that introduce artificial attenuation and phase shifts in the signal. We introduce a fingerprint plot type to be able to distinguish between various plants and other specimens, and can actually detect the aqueous state of a plant.

The main challenges to the sustainable development of humanity were identified and ways to win those challenges proposed, by changing the key concepts in education, science and governance. We conclude that urgent measures should be implemented to avoid the impending catastrophe.

The Energy Theory of Value is presented on basis of clearly defined physical principles of energy and entropy. It is put in three postulates: economy is energy consumption, the universe (and thus economy) needs to increase its entropy, and in a free market every trade leaves people happier (defined in physical objectives). For the energy equivalence, we find a current energy value of 170 mW economy per (2019) US$/year. Three basic questions are asked and answered: Is unfettered capitalism possible? Can we manage a steady-state economy in a free market? Do the energy transition policies make sense? It is found that if energy consumption is reduced, it will push many people into abject poverty.

Climate change is an important societal issue.Large effort in society is spent on addressing it.For adequate measures, it is important that the phenomenon of climate change is well understood, especially the effect of adding carbon dioxide to the atmosphere.In this work, a theoretical fully analytical study is presented of the so-called greenhouse effect of carbon dioxide.The effect of this gas in the atmosphere itself was already determined as being of little importance based on empirical analysis.In the current work, the effect is studied both phenomenologically and analytically.In a first attempt of energy transfer by radiation only, it is solved by ideal-gas-law equations and the atmosphere is divided into an infinite number of layers each absorbing and reemitting infrared radiation (surpassing the classical Beer-Lambert analysis of absorption).The result is that the exact structure of the atmosphere is irrelevant for the analysis; we might as well keep the two-box model for any analytical approach.However, the results are unsatisfactory in that they cannot explain the profile of the atmosphere.In a new approach, the atmosphere is solved by taking both radiative as well as thermodynamic processes into account.The model fully fits the empirical data and an analytical equation is given for the atmospheric behavior.Upper limits are found for the greenhouse effect ranging from zero to a couple of mK per ppm CO 2 .It is shown that it cannot explain the observed correlation of carbon dioxide and surface temperature.This correlation, however, is readily explained by Henry's Law (outgassing of oceans), with other phenomena insignificant.Finally, while the greenhouse effect can thus, in a rudimentary way, explain the behavior of the atmosphere of Earth, it fails describing other atmospheres such as that of Mars.Moreover, looking at three cities in Spain, it is found that radiation balances only cannot explain the temperature of these cities.Finally, three data sets with different time scales (60 years, 600 thousand years, and 650 million years) show markedly different behavior, something that is inexplicable in the framework of the greenhouse theory.

In this research we tried to answer the question: How to optimize the total production of economy. For finding the answer we used two postulates: First, a worker is incentivated to work if it pays off. When in the income ranking the neighbor below earns less and the one above earns more the worker will work harder and produce more. The productivity of the worker is proportional to this ’derivative’ in the income curve. (Note: a worker’s salary is not assumed necessarily proportional to his productivity). The second postulate depends on who is in control of the production process. In highly-simplified naming: In capitalism, the capital takes the decisions, in a democracy the people do, by vote. We also simulated a dictatorial system in which decisions can be imposedby a (benevolent) dictator. We used these ingredients in evolutionary computation. Starting with an arbitrary initial distribution, we make random small changes to it and if the total production increases, a decision will be made whether to implement these changes. This procedure is repeated until the distribution is stable. Remarkably, the outcomes for ’democracy’ and ’capitalism’ are similar. Capitalism and democracy go hand-in-hand together: One person getting all income, two people working, and most not working and not receiving. These results are also analytically found. In ’communism’, nobody works and everybody perishes. In a ’dictatorial’ system we can optimize production for the benefit of the people, and come to the conclusion that the introduction of minimum wages is beneficial, and these should be 50% of the average income.

The dynamics of carbon dioxide in the atmosphere is analyzed and it is shown that the Pinatubo eruption in 1991 had a noticeable effect on these dynamics.The growth rate slowed down.Moreover, analyzing the year-on-year CO 2 growth data, we can see an anthropogenic footprint, possibly due to the burning of fossil fuels.On top of this anthropogenic contribution is a natural contribution that is of similar magnitude, and that closely follows the ocean surface temperature (influenced by ENSO, El Niño Southern Oscillation).This latter fact is consistent with the hypothesis of the correlation of global temperatures and carbon-dioxide in the atmosphere being governed by Henry's Law, in which carbon dioxide variations are the result of, rather than the cause of, temperature changes.This latter being the so-called "greenhouse effect", sometimes mentioned as responsible for (anthropogenic) climate changes, and that cannot explain the observed phenomena described here.Similar conclusions are drawn on monthly data of carbon dioxide and temperature as well.

One of the results of Anthropogenic Global Warming is the acidification of the oceans which threatens wildlife on this planet. In this work it will be shown what will be the effect of carbon dioxide injected into the atmosphere, doubling the total amount from 350 ppm to 700 ppm. Principally the effect on carbonate ions CO32-. It is based on textbook chemical principles worked out by numerically solving the resulting non-linear equations by the bisection method. The results are the following: In a pure-water environment the effect is that carbonate ion concentration remains unaltered (i.e., no harm to coral reefs). In a constant-pH environment the carbonate ion concentration grows linearly with CO2 in the atmosphere (i.e., good for coral reefs). When lowering the pH by other means than CO2, the carbonate ion concentration drops linearly (i.e., bad for coral reefs). In some specific cases can raising the CO2 in the atmosphere slightly reduce carbonate ions in the oceans.

One of the ingredients of anthropogenic global warming is the existence of a large correlation between carbon dioxide concentrations in the atmosphere and the temperature.In this work we analyze the original time-series data that led to the new wave of climate research and test the two hypotheses that might explain this correlation, namely the (more commonly accepted and well-known) greenhouse effect (GHE) and the less-known Henry's Law (HL).This is done by using the correlation and the temporal features of the data.Our conclusion is that of the two hypotheses the greenhouse effect is less likely, whereas the Henry's Law hypothesis can easily explain all effects.First the proportionality constant in the correlation is correct for HL and is about two orders of magnitude wrong for GHE.Moreover, GHE cannot readily explain the concurring methane signals observed.On the temporal scale, we see that GHE has difficulty in the apparent negative time lag between cause and effect, whereas in HL this is of correct sign and magnitude, since it is outgasing of gases from oceans.Introducing feedback into the GHE model can overcome some of these problems, but it introduces highly instable and chaotic behavior in the system, something that is not observed.The HL model does not need feedback.

One of the ingredients of the anthropogenic global warming hypothesis is the existence of large positive feedback in the climate system. An example is polar ice that, once melted, turns into blacker water that will increase radiation absorption and this rein-forces the melting. This causes a run-away scenario with a point of no return. Here it is shown that the polar ice can also have negative feedback aspects, where a melting of polar ice will cause it to reappear.

It is common to use past information about the system modeled in probabilistic statistics to make predictions about the future. Especially in the area of climate modeling and forecasting this is done. Here it is argued that doing this in a purely empirical way is full of perils and pitfalls. Without knowledge of the underlying physical laws it will go wrong sooner or later. Specifically, the distribution functions are analyzed, which are normally assumed to be well-behaved gaussian-like not because there is a reason for it, but only because they don’t cause mathematical problems. Real functions (like power laws) will prohibit any statistical analysis and thus prediction model. Furthermore, correlations and extrapolations are considered. The first show that correlations come in many types and not all of them have a direct causation link. The specific case of extreme events is used as an example to highlight the difficulty and the pitfalls of empirical forecasting in general. The conclusion is that empirical forecasting cannot be used for science.

Society is living in fear of catastrophic climate scenarios, the so called Anthropogenic Global Warming (AGW) theory. It is a multidisciplinary subject; this paper analyzes the psychology behind such thinking which is governing the perception and politics of the subject. It does this in so-called Game Theory decision tables for people's thinking. We come to the conclusion that current opinion in society will shift from 'active believer' to 'passive believer' to 'active non-believer' if evidence against AGW will continue to accumulate.

Carrier multiplication is demonstrated in a solid-state dispersion of germanium nanocrystals in a silicon–dioxide matrix. This is performed by comparing ultrafast photo-induced absorption transients at different pump photon energies below and above the threshold energy for this process. The average germanium nanocrystal size is approximately 5–6 nm, as inferred from photoluminescence and Raman spectra. A carrier multiplication efficiency of approximately 190% is measured for photo-excitation at 2.8 times the optical bandgap of germanium nanocrystals, deduced from their photoluminescence spectra. Germanium nanocrystals can efficiently generate more than one electron–hole pair following absorption of a single photon of light. That is the finding of a study by scientists from the Netherlands and Portugal. Carrier multiplication — the ability of a semiconductor to create several electron–hole pairs from the absorption of a single photon whose energy exceeds the material’s bandgap — is potentially important for improving the efficiencies of devices like solar cells and photodetectors. In the present study, 5–6 nm diameter germanium nanocrystals inside a silicon-dioxide matrix offer carrier multiplication with an efficiency of 190% for a photon energy of 3.5 eV, which implies that 1.9 electron electron–hole pairs are created for each absorbed photon with 2.8 times the bandgap energy. Importantly, this efficiency is significantly better than that of bulk germanium.