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UNQUESTIONABLY, the Civilian Conservation Corps (CCC) was one of the most successful of the New Deal agencies. Despite the fact that it was conceived and developed in a very short [...]

HISTORIANS have often observed that to capture the real past is impossible, that the best one can hope for is to construct a partial view based on one's perception of [...]

Focuses on the candidacy of George Washington Armstrong during the 1932 gubernatorial election in Texas. Personal background; Educational background; Views on economic and political policies; Campaign strategies; Reasons why he was defeated.

Probability, Random Signals, and Statistics, by X. Rong LI, Boca Raton, FL: CRC Press, 1999, ISBN 0-8493-0433-4, 455 pp. + CD, $69.95. This textbook is intended for an audience of [...]

The article presents a case study in integrated agricultural development, focusing on the operations of World Neighbors, a voluntary development organization, in Honduras. It discusses the success of the agricultural development program of World Neighbors in this state. According to the author, the organization's first project was in Guinope where severe soil erosion resulted in soil deterioration was pervasive. Its second project, a green manure project was in El Rosario. He opines that World Neighbors has successfully demonstrated that the Third World has the potential to feed itself.

Riparian (streamside) vegetation may help control transport of sediments and chemicals to stream channels. Studies of a coastal plain agricultural watershed showed that riparian forest ecosystems are excellent nutrient sinks and buffer the nutrient discharge from surrounding agroecosystems. Nutrient uptake and removal by soil and vegetation in the riparian forest ecosystem prevented outputs from agricultural uplands from reaching the stream channel. The riparian ecosystem can apparently serve as both a short- and long-term nutrient filter and sink if trees are harvested periodically to ensure a net uptake of nutrients. (Accepted for publication 28 November 1983) [ABSTRACT FROM AUTHOR]

The article focuses on the pro-war socialists, the social democratic league and the ill-fated drive for industrial democracy in the U.S. during the period 1917 to 1920. The entry of the U.S. into World War I was an event of great significance for the American Socialist Party, since the Socialist movement in the country virtually disintegrated as a result of developments growing out of the wartime experience. Causes of the collapse included the government's reaction to the anti-war posture of SPA; and perhaps more important, the party's internal disruption brought on by the defection of its extreme left wing. The present discussion, however, deals with these factors only indirectly. Instead, attention is focused upon a much less widely known aspect of the wartime collapse of American socialism, the defection of its extreme right. While this defection did not have as serious an effect on the party as other developments, it nonetheless produced destructive consequences, for it robbed Socialists of some of their most eloquent spokesmen, imaginative leaders and best-known members.

The article discusses various papers published within the issue including one by James S. Olson on the cure for childhood leukemia and another by Hannah Vaughan on the social, political, and environmental importance of a bath house.

The article discusses various reports published within the issue, including one by Jennifer M. Ross-Nazzal and colleagues on how NASA impacted the Clear Lake Area, Texas during the early 1960's and another one by JoAnn Pospisil on franchising and selling West Texas water resources.

In this journal introduction, the editor discusses articles within the issue dealing with such topics as influential Texan female authors, female astronauts, and Women Air Force Service Pilots (WASP) in World War II.

Two-dimensional (2D) semiconductors are promising candidates for optoelectronic application and quantum information processes due to their inherent out-of-plane 2D confinement. In addition, they offer the possibility of achieving low-dimensional in-plane exciton confinement, similar to zero-dimensional quantum dots, with intriguing optical and electronic properties via strain or composition engineering. However, realizing such laterally confined 2D monolayers and systematically controlling size-dependent optical properties remain significant challenges. Here, we report the observation of lateral confinement of excitons in epitaxially grown in-plane MoSe 2 quantum dots (~15-60 nm wide) inside a continuous matrix of WSe 2 monolayer film via a sequential epitaxial growth process. Various optical spectroscopy techniques reveal the size-dependent exciton confinement in the MoSe 2 monolayer quantum dots with exciton blue shift (12-40 meV) at a low temperature as compared to continuous monolayer MoSe 2 . Finally, single-photon emission (g 2 (0) ~ 0.4) was also observed from the smallest dots at 1.6 K. Our study opens the door to compositionally engineered, tunable, in-plane quantum light sources in 2D semiconductors., (© 2024. The Author(s).)

Rangelands are the dominant land use across a broad swath of central North America where they span a wide gradient, from <350 to >900 mm, in mean annual precipitation. Substantial efforts have examined temporal and spatial variation in aboveground net primary production (ANPP) to precipitation (PPT) across this gradient. In contrast, net secondary productivity (NSP, e.g., primary consumer production) has not been evaluated analogously. However, livestock production, which is a form of NSP or primary consumer production supported by primary production, is the dominant non-cultivated land use and an integral economic driver in these regions. Here, we used long-term (mean length = 19 years) ANPP and NSP data from six research sites across the Central Great Plains with a history of a conservative stocking to determine resource (i.e., PPT)-productivity relationships, NSP sensitivities to dry-year precipitation, and regional trophic efficiencies (e.g., NSP:ANPP ratio). PPT-ANPP relationships were linear for both temporal (site-based) and spatial (among site) gradients. The spatial PPT-NSP model revealed that PPT mediated a saturating relationship for NSP as sites became more mesic, a finding that contrasts with many plant-based PPT-ANPP relationships. A saturating response to high growing-season precipitation suggests biogeochemical rather than vegetation growth constraints may govern NSP (i.e., large herbivore production). Differential sensitivity in NSP to dry years demonstrated that the primary consumer production response heightened as sites became more xeric. Although sensitivity generally decreased with increasing precipitation as predicted from known PPT-ANPP relationships, evidence suggests that the dominant species' identity and traits influenced secondary production efficiency. Non-native northern mixed-grass prairie was outperformed by native Central Great Plains rangeland in sensitivity to dry years and efficiency in converting ANPP to NSP. A more comprehensive understanding of the mechanisms leading to differences in producer and consumer responses will require multisite experiments to assess biotic and abiotic determinants of multi-trophic level efficiency and sensitivity., (© 2024 The Authors. Ecological Applications published by Wiley Periodicals LLC on behalf of The Ecological Society of America.)

Observation of interlayer, charge transfer (CT) excitons in van der Waals heterostructures (vdWHs) based on 2D-2D systems has been well investigated. While conceptually interesting, these charge transfer excitons are highly delocalized and spatially localizing them requires twisting layers at very specific angles. This issue of localizing the CT excitons can be overcome via making nanoplate-2D material heterostructures (N2DHs) where one of the components is a spatially quantum confined medium. Here, we demonstrate the formation of CT excitons in a mixed dimensional system comprising MoSe 2 and WSe 2 monolayers and CdSe/CdS-based core/shell nanoplates (NPLs). Spectral signatures of CT excitons in our N2DHs were resolved locally at the 2D/single-NPL heterointerface using tip-enhanced photoluminescence (TEPL) at room temperature. By varying both the 2D material and the shell thickness of the NPLs and applying an out-of-plane electric field, the exciton resonance energy was tuned by up to 100 meV. Our finding is a significant step toward the realization of highly tunable N2DH-based next-generation photonic devices.

Quantum emitters are essential components of quantum photonic circuitry envisioned beyond the current optoelectronic state-of-the-art. Two dimensional materials are attractive hosts for such emitters. However, the high single photon purity required is rarely realized due to the presence of spectrally degenerate classical light originating from defects. Here, we show that design of a van der Waals heterostructure effectively eliminates this spurious light, resulting in purities suitable for a variety of quantum technological applications. Single photon purity from emitters in monolayer WSe 2 increases from 60% to 92% by incorporating this monolayer in a simple graphite/WSe 2 heterostructure. Fast interlayer charge transfer quenches a broad photoluminescence background by preventing radiative recombination through long-lived defect bound exciton states. This approach is generally applicable to other 2D emitter materials, circumvents issues of material quality, and offers a path forward to achieve the ultrahigh single photon purities ultimately required for photon-based quantum technologies.

We investigate the influence of quantum interference (QI) and broken spin-symmetry on the thermoelectric response of node-possessing junctions, finding a dramatic enhancement of the spin-thermopower ( S s ), figure-of-merit ( Z s T ), and maximum thermodynamic efficiency (η s max ) caused by destructive QI. Using many-body and single-particle methods, we calculate the response of 1,3-benzenedithiol and cross-conjugated molecule-based junctions subject to an applied magnetic field, finding nearly universal behavior over a range of junction parameters with S s , Z s T , and reaching peak values of 2 π / 3 ( k / e ) , 1.51, and 28% of Carnot efficiency, respectively. We also find that the quantum-enhanced spin-response is spectrally broad, and the field required to achieve peak efficiency scales with temperature. The influence of off-resonant thermal channels (e.g., phonon heat transport) on this effect is also investigated.