Human Appropriation of Net Primary Production: From a Planet to a Pixel

Human appropriation of net primary production (HANPP) is a substantial improvement upon 20th century attempts at developing an ecological footprint indicator because of its measurability in relation to net primary production, its close relationship to other key footprint measures, such as carbon and water, and its spatial specificity. This paper explores HANPP across four geographical scales: through literature review, the planet; through reanalysis of existing data, variations among the world’s countries; and through novel analyses, U.S. counties and the 30 m pixel scale for one U.S. county. Results show that HANPP informs different sustainability narratives at different scales. At the planetary scale, HANPP is a critical planetary limit that improves upon areal land use indicators. At the country macroscale, HANPP indicates the degree to which meeting the needs of the domestic population for provisioning ecosystem services (food, feed, biofiber, biofuel) presses against the domestic ecological endowment of net primary production. At the county mesoscale, HANPP reveals the dependency of metropolitan areas upon regional specialized rural forestry and agroecosystems to which they are teleconnected through trade and transport infrastructures. At the pixel microscale, HANPP provides the basis for deriving spatial patterns of remaining net primary production upon which biodiversity and regulatory and cultural ecosystem services are dependent. HANPP is thus a sustainability indicator that can fulfill similar needs as carbon, water and other footprints

Book Review Rural Education in America: What Works for Our Students, Teachers, and Communities

Access the online Pressbooks version of this article here. Book review of Marietta, G. & S. Marietta. (2020). Rural Education in America, What works for our students, teachers, and communities, Harvard Education Press. Statewide faculty teaching in rural Utah review this book and focus on actions to meet the specific needs of their demographic of rural students in rural communities. The reviewer’s reflections on the book developed from a Spring 2022 Empowering Teaching Excellence Learning Circle led by the primary author

Allocation of U.S. Biomass Production to Food, Feed, Fiber, Fuel and Exports

This paper analyzes the end uses—food, feed, fiber, fuel, and exports—of biomass production in the U.S. in 1997, 2002, 2007, and 2012. They are also analyzed at the state level in 2012. Biomass production is measured as human appropriation of net primary production (HANPP), an ecological footprint measured as carbon fixed through photosynthesis, derived from data on crop, timber and grazing yields. HANPP was allocated to end uses using publicly available sources from the U.S. Department of Agriculture and internet-based sources publishing data on agricultural trade. HANPP was 717–834 megatons (MT) of carbon per year, which comprised 515–615 MT of crop-based, 105–149 MT timber-based, and 64–76 MT of grazed HANPP. Livestock feed commanded the largest proportion, but decreased from 395 (50%) to 305 MT (42%) of all HANPP and 320 to 240 MT (58–44%) of crop-based HANPP. The proportion allocated to exports was stable at 118–141 MT (17–18%) of total HANPP and 112–133 MT (21–23%) of crop-based HANPP. Biofiber decreased from 141 MT (18%) to 97 MT (13%) of all HANPP. Biofuel increased strongly from 11 MT to 98 MT, from 1% to 14% of all HANPP and 2% to 18% of crop-based HANPP, surpassing food and biofiber by 2012. Direct food commanded 89–105 MT, the lowest proportion at 12–13% of all HANPP, and 17–18% of crop-based HANPP. The highly fertile Midwest and the drought-prone Intermountain West stand out as regions where a very small percentage of biomass is allocated to direct human food. The high proportions of biomass production allocated to nonfood uses is consistent with the tragedy of ecosystem services and commodification of nature frameworks. Reducing these proportions presents opportunities for improving ecosystem services, food security, and human well-being

Performance Analysis of ML-based MTC Traffic Pattern Predictors

Prolonging the lifetime of massive machine-type communication (MTC) networks is key to realizing a sustainable digitized society. Great energy savings can be achieved by accurately predicting MTC traffic followed by properly designed resource allocation mechanisms. However, selecting the proper MTC traffic predictor is not straightforward and depends on accuracy/complexity trade-offs and the specific MTC applications and network characteristics. Remarkably, the related state-of-the-art literature still lacks such debates. Herein, we assess the performance of several machine learning (ML) methods to predict Poisson and quasi-periodic MTC traffic in terms of accuracy and computational cost. Results show that the temporal convolutional network (TCN) outperforms the long-short term memory (LSTM), the gated recurrent units (GRU), and the recurrent neural network (RNN), in that order. For Poisson traffic, the accuracy gap between the predictors is larger than under quasi-periodic traffic. Finally, we show that running a TCN predictor is around three times more costly than other methods, while the training/inference time is the greatest/least.Comment: IEEE Wireless Communications Letters Print ISSN: 2162-2337 Online ISSN: 2162-234

Clinically significant personality traits in individuals at high risk of developing psychosis

It is still unclear to what extent personality may influence the development of psychosis. We aimed to explore significant personality traits in individuals at high-risk (HR) for psychosis. Personalities of forty HR individuals and a matched sample of 40 HVs were evaluated with the Millon Multiaxial Inventory (MCMI-III). They were also assessed with the Positive and Negative Symptoms Scale (PANSS), Beck Depression and Anxiety Inventories (BDI-II and BAI), Global Assessment of Functioning (GAF) and Mini-International Neuropsychiatric Interview (MINI 6.0.0). Fisher's exact test was employed to compare frequency of traits. Mann-Whitney U test and logistic regression were used to establish relationships between traits and symptoms, and the effect of age, sex and symptoms on such traits. Most HR individuals (97.5%) had at least one significant trait; 75% had personality disorders, mainly depressive, borderline or schizotypal. Only histrionic and narcissistic traits were more prevalent in HVs. Negative symptoms were related to schizoid and paranoid traits. Depression was more severe with borderline traits. Most HR individuals (67.6%) had more than one DSM-IV Axis I diagnosis, mainly depressive/anxiety disorders. Transition rate was low (5%). Certain personality profiles may not be markers for conversions to psychosis but contribute to high morbidity in HR individuals

Hematite photoelectrodes grown on porous CuO–Sb₂O₅–SnO₂ ceramics for photoelectrochemical water splitting

Photoelectrodes capable of cost-effective hydrogen production on a large scale, via photoelectrochemical water splitting under solar light, could offer an elegant solution to many current problems of humankind caused by over-reliance on fossil fuels and the resulting environmental pollution. The search and design of low-cost photoelectrode materials and substrates for practical applications are required. In this work, unmodified hematite photoanodes grown by metal-organic chemical vapor deposition (MO-CVD) onto CuO–Sb2O5–SnO2 ceramic substrates are reported. The deposition time of hematite precursor varied between 10 min, 60 min, and 90 min. The photoanode grown for 60 min exhibits the highest photocurrent density recorded at 1.23 V vs RHE (reversible hydrogen electrode): 4.79 mA/cm2 under blue light of Thorlabs LED M455L2 (455 nm), 0.41 mA/cm2 under the radiation of the real sun in Mexico, and 0.38 mA/cm2 under AM1.5G solar simulator conditions. The high porosity of CuO–Sb2O5–SnO2 ceramics permits the permeation of the hematite precursor into the substrate bulk, which results in 3D-growth of a thin Fe2O3-coating (50 nm or less) on conductive SnO2-grains in the ceramics to a depth of ca. 5 μm. The thick photocatalytic layer (SnO2-grains coated by hematite) of several micrometers assures a good light harvesting by the photoelectrode, while the nano-sized Fe2O3-films on conductive SnO2-grains is favorable for charge diffusion. This architecture of the photoelectrode results in good photoelectrochemical characteristics and is promising for further development.</p

Waveguide manufacturing technologies for next-generation millimeter-wave antennas

Some recent waveguide-based antennas are presented in this paper, designed for the next generation of communication systems operating at the millimeter-wave band. The presented prototypes have been conceived to be manufactured using different state-of-the-art techniques, involving subtractive and additive approaches. All the designs have used the latest developments in the field of manufacturing to guarantee the required accuracy for operation at millimeter-wave frequencies, where tolerances are extremely tight. Different designs will be presented, including a monopulse antenna combining a comparator network, a mode converter, and a spline profile horn; a tunable phase shifter that is integrated into an array to implement reconfigurability of the main lobe direction; and a conformal array antenna. These prototypes were manufactured by diverse approaches taking into account the waveguide configuration, combining parts with high-precision milling, electrical discharge machining, direct metal laser sintering, or stereolithography with spray metallization, showing very competitive performances at the millimeter-wave band till 40 GHzThis work was supported by the Spanish Government under Grant TEC2016-76070- C3-1/2-R (ADDMATE); in part under Grant PID2020-116968RB-C32/33 (DEWICOM), Agencia Estatal de Investigación MCIN/AEI/10.13039/501100011033, Fondo Europeo de Desarrollo Regional: AEI/FEDER, UE. This work was also partially supported under Grant S2013/ICE3000 (SPADERADARCM), Madrid Regional Governmen

Plane waves in quantum gravity: breakdown of the classical spacetime

Starting with the Hamiltonian formulation for spacetimes with two commuting spacelike Killing vectors, we construct a midisuperspace model for linearly polarized plane waves in vacuum gravity. This model has no constraints and its degrees of freedom can be interpreted as an infinite and continuous set of annihilation and creation like variables. We also consider a simplified version of the model, in which the number of modes is restricted to a discrete set. In both cases, the quantization is achieved by introducing a Fock representation. We find regularized operators to represent the metric and discuss whether the coherent states of the quantum theory are peaked around classical spacetimes. It is shown that, although the expectation value of the metric on Killing orbits coincides with a classical solution, its relative fluctuations become significant when one approaches a region where null geodesics are focused. In that region, the spacetimes described by coherent states fail to admit an approximate classical description. This result applies as well to the vacuum of the theory.Comment: 11 pages, no figures, version accepted for publication in Phys. Rev.