Work distribution for the driven harmonic oscillator with time-dependent strength: Exact solution and slow driving

We study the work distribution of a single particle moving in a harmonic oscillator with time-dependent strength. This simple system has a non-Gaussian work distribution with exponential tails. The time evolution of the corresponding moment generating function is given by two coupled ordinary differential equations that are solved numerically. Based on this result we study the behavior of the work distribution in the limit of slow but finite driving and show that it approaches a Gaussian distribution arbitrarily well

New genera of meliturguline bees from Saudi Arabia and Persia, with notes on related genera and a key to the Arabian fauna (Hymenoptera: Andrenidae)

A new genus of melitturgine bees (Panurginae: Melitturgini) is described and figured from central Saudi Arabia. Belliturgula najdica Engel, gen. et sp. n., is similar in several respects to the genus Flavomeliturgula Patiny in that both have a greatly elongate glossa that is longer than the face and is truncate apically. The former differs in the greatly elongate and flattened first labial palpomere, the remaining palpomeres unmodified, the greatly protuberant clypeus, and long labrum lacking dense setal patches, among other traits. In addition, remarks are made on the composition of Flavomeliturgula, with Meliturgula deserta Warncke (Iran, Pakistan), removed to Khuzimelissa Engel, gen. n., resulting in the new combination Khuzimelissa deserta (Warncke), comb. n. Khuzimelissa differs from Flavomeliturgula by the unmodified labial palpomeres (lacking the elongate first three labial palpomeres of the latter genus), the acute glossa (broadly truncate in the latter), glossa shorter than head length (greater than head length in the latter), the abundant, white, squamiform setae of the mesoscutum (sparse, erect setae in the latter), cleft pretarsal claws (simple in the latter), presence of metasomal setal bands (lacking in the latter), and apically emarginate pygidial plate (acutely rounded in the latter). The species of Flavomeliturgula are organized into three subgenera, including Koreshomelissa Engel, subgen. n., and Freyamelissa Engel, subgen. n., and these may eventually warrant generic status once phylogenetic work on the tribe has been completed. A key to the Arabian genera of Panurginae is provided, along with an augmented key to the genera of subtribe Meliturgulina

New genera of meliturguline bees from Saudi Arabia and Persia, with notes on related genera and a key to the Arabian fauna (Hymenoptera: Andrenidae)

A new genus of melitturgine bees (Panurginae: Melitturgini) is described and figured from central Saudi Arabia. Belliturgula najdica Engel, gen. et sp. n., is similar in several respects to the genus Flavomeliturgula Patiny in that both have a greatly elongate glossa that is longer than the face and is truncate apically. The former differs in the greatly elongate and flattened first labial palpomere, the remaining palpomeres unmodified, the greatly protuberant clypeus, and long labrum lacking dense setal patches, among other traits. In addition, remarks are made on the composition of Flavomeliturgula, with Meliturgula deserta Warncke (Iran, Pakistan), removed to Khuzimelissa Engel, gen. n., resulting in the new combination Khuzimelissa deserta (Warncke), comb. n. Khuzimelissa differs from Flavomeliturgula by the unmodified labial palpomeres (lacking the elongate first three labial palpomeres of the latter genus), the acute glossa (broadly truncate in the latter), glossa shorter than head length (greater than head length in the latter), the abundant, white, squamiform setae of the mesoscutum (sparse, erect setae in the latter), cleft pretarsal claws (simple in the latter), presence of metasomal setal bands (lacking in the latter), and apically emarginate pygidial plate (acutely rounded in the latter). The species of Flavomeliturgula are organized into three subgenera, including Koreshomelissa Engel, subgen. n., and Freyamelissa Engel, subgen. n., and these may eventually warrant generic status once phylogenetic work on the tribe has been completed. A key to the Arabian genera of Panurginae is provided, along with an augmented key to the genera of subtribe Meliturgulina

Controls on mangrove forest-atmosphere carbon dioxide exchanges in western Everglades National Park

We report on net ecosystem production (NEP) and key environmental controls on net ecosystem exchange (NEE) of carbon dioxide (CO2) between a mangrove forest and the atmosphere in the coastal Florida Everglades. An eddy covariance system deployed above the canopy was used to determine NEE during January 2004 through August 2005. Maximum daytime NEE ranged from −20 to −25 mmol (CO2) m−2 s−1 between March and May. Respiration (Rd) was highly variable (2.81 ± 2.41 mmol (CO2) m−2 s−1), reaching peak values during the summer wet season. During the winter dry season, forest CO2 assimilation increased with the proportion of diffuse solar irradiance in response to greater radiative transfer in the forest canopy. Surface water salinity and tidal activity were also important controls on NEE. Daily light use efficiency was reduced at high (\u3e34 parts per thousand (ppt)) compared to low (ppt) salinity by 46%. Tidal inundation lowered daytime Rd by ∼0.9 mmol (CO2) m−2 s−1 and nighttime Rd by ∼0.5 mmol (CO2) m−2 s−1. The forest was a sink for atmospheric CO2, with an annual NEP of 1170 ± 127 g C m−2 during 2004. This unusually high NEP was attributed to year‐round productivity and low ecosystem respiration which reached a maximum of only 3 g C m−2 d−1. Tidal export of dissolved inorganic carbon derived from belowground respiration likely lowered the estimates of mangrove forest respiration. These results suggest that carbon balance in mangrove coastal systems will change in response to variable salinity and inundation patterns, possibly resulting from secular sea level rise and climate change. Citation: Barr, J. G., V. Engel, J. D. Fuentes

The Threat of Capital Drain: A Rationale for Public Banks?

This paper yields a rationale for why subsidized public banks may be desirable from a regional perspective in a financially integrated economy. We present a model with credit rationing and heterogeneous regions in which public banks prevent a capital drain from poorer to richer regions by subsidizing local depositors, for example, through a public guarantee. Under some conditions, cooperative banks can perform the same function without any subsidization; however, they may be crowded out by public banks. We also discuss the impact of the political structure on the emergence of public banks in a political-economy setting and the role of interregional mobility

Topological kink plasmons on magnetic-domain boundaries.

Two-dimensional topological materials bearing time reversal-breaking magnetic fields support protected one-way edge modes. Normally, these edge modes adhere to physical edges where material properties change abruptly. However, even in homogeneous materials, topology still permits a unique form of edge modes - kink modes - residing at the domain boundaries of magnetic fields within the materials. This scenario, despite being predicted in theory, has rarely been demonstrated experimentally. Here, we report our observation of topologically-protected high-frequency kink modes - kink magnetoplasmons (KMPs) - in a GaAs/AlGaAs two-dimensional electron gas (2DEG) system. These KMPs arise at a domain boundary projected from an externally-patterned magnetic field onto a uniform 2DEG. They propagate unidirectionally along the boundary, protected by a difference of gap Chern numbers ([Formula: see text]) in the two domains. They exhibit large tunability under an applied magnetic field or gate voltage, and clear signatures of nonreciprocity even under weak-coupling to evanescent photons

New genus of Meliponini.

33 pages : color illustrations, color map ; 26 cm.A new genus of stingless bees (Apinae: Meliponini) is described and figured from Indonesia (Sulawesi), known from a single species previously placed in Geniotrigona Moure. Based on recent phylogenetic studies, Trigona (Geniotrigona) incisa Sakagami and Inoue renders Geniotrigona polyphyletic and is more closely related to Lepidotrigona Moure. The species is transferred to Wallacetrigona Engel and Rasmussen, new genus, and differentiated from Geniotrigona proper as well as all other meliponines occurring in Sundaland, Wallacea, and Sahul (Australinea). The new genus occurs east of the Wallace Line and separate from the distribution of Geniotrigona, which is otherwise restricted to Sundaland, but Wallacetrigona is presently not known beyond the Weber Line. A hierarchical classification of Indomalayan and Australasian stingless bees is tabulated and a revised key to the genera and subgenera provided, as well as an appendix tabulating the species and synonyms. The following new combinations are established: Wallacetrigona incisa (Sakagami and Inoue), Homotrigona (Lophotrigona) canifrons (Smith), Homotrigona (Odontotrigona) haematoptera (Cockerell), Homotrigona (Tetrigona) apicalis (Smith), H. (T.) binghami (Schwarz), H. (T.) melanoleuca (Cockerell), H. (T.) peninsularis (Cockerell), and H. (T.) vidua (Lepeletier de Saint Fargeau)

New genera of meliturguline bees from Saudi Arabia and Persia, with notes on related genera and a key to the Arabian fauna (Hymenoptera: Andrenidae)

A new genus of melitturgine bees (Panurginae: Melitturgini) is described and figured from central Saudi Arabia. Belliturgula najdica Engel, gen. et sp. n., is similar in several respects to the genus Flavomeliturgula Patiny in that both have a greatly elongate glossa that is longer than the face and is truncate apically. The former differs in the greatly elongate and flattened first labial palpomere, the remaining palpomeres unmodified, the greatly protuberant clypeus, and long labrum lacking dense setal patches, among other traits. In addition, remarks are made on the composition of Flavomeliturgula, with Meliturgula deserta Warncke (Iran, Pakistan), removed to Khuzimelissa Engel, gen. n., resulting in the new combination Khuzimelissa deserta (Warncke), comb. n. Khuzimelissa differs from Flavomeliturgula by the unmodified labial palpomeres (lacking the elongate first three labial palpomeres of the latter genus), the acute glossa (broadly truncate in the latter), glossa shorter than head length (greater than head length in the latter), the abundant, white, squamiform setae of the mesoscutum (sparse, erect setae in the latter), cleft pretarsal claws (simple in the latter), presence of metasomal setal bands (lacking in the latter), and apically emarginate pygidial plate (acutely rounded in the latter). The species of Flavomeliturgula are organized into three subgenera, including Koreshomelissa Engel, subgen. n., and Freyamelissa Engel, subgen. n., and these may eventually warrant generic status once phylogenetic work on the tribe has been completed. A key to the Arabian genera of Panurginae is provided, along with an augmented key to the genera of subtribe Meliturgulina

Calibration of TCCON column-averaged CO2: the first aircraft campaign over European TCCON sites

The Total Carbon Column Observing Network (TCCON) is a ground-based network of Fourier Transform Spectrometer (FTS) sites around the globe, where the column abundances of CO2, CH4, N2O, CO and O2 are measured. CO2 is constrained with a precision better than 0.25% (1-σ). To achieve a similarly high accuracy, calibration to World Meteorological Organization (WMO) standards is required. This paper introduces the first aircraft calibration campaign of five European TCCON sites and a mobile FTS instrument. A series of WMO standards in-situ profiles were obtained over European TCCON sites via aircraft and compared with retrievals of CO2 column amounts from the TCCON instruments. The results of the campaign show that the FTS measurements are consistently biased 1.1% ± 0.2% low with respect to WMO standards, in agreement with previous TCCON calibration campaigns. The standard a priori profile for the TCCON FTS retrievals is shown to not add a bias. The same calibration factor is generated using aircraft profiles as a priori and with the TCCON standard a priori. With a calibration to WMO standards, the highly precise TCCON CO2 measurements of total column concentrations provide a suitable database for the calibration and validation of nadir-viewing satellite