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Type I secretion systems for microcin export in Gram-negative bacteria transport small antibacterial proteins from the cytoplasm to the extracellular environment in a single step. In nature, each secretion system is generally paired with a specific small protein.

It is commonly recognised that natural history datasets contain locality errors that can compromise the utility of those datasets. However, another source of error in these datasets is taxonomic misidentifications, and this type of error is potentially common, particularly with regards to morphologically conservative species. For example, in the African skinks, the Trachylepis striata and T. varia species complexes each contain morphologically similar species that are commonly confused, despite being genetically distinct. Some species also are partly sympatric, and misidentifications are likely to be especially problematic in those areas. Using DNA barcoding, we assessed misidentification rates between species and applied the updated identifications to known distribution maps to examine whether those maps are accurate representations. Existing banked samples and newly collected samples were DNA barcoded using the mitochondrial 16S gene and supplemented with GenBank data. Identifications were made by matching sequences using haplotype networks that included material from near type localities. The barcode-based identifications were compared with the original identifications recorded for those samples. Taxonomic error was common, particularly in areas of presumed sympatry (error for T. striata species complex: 28%; T. varia species complex: 31%) and this resulted in inaccurately represented species distributions and areas of sympatry. Areas of sympatry were, however, confirmed for T. spilogaster/T. punctatissima, T. striata/T. punctatissima and T. damarana/T. laevigata/T. varia. Our findings corroborate other studies that demonstrate taxonomic error in existing datasets is a significant, but typically unrecognised problem, particularly for morphologically conservative species. This has implications for the utility of historical collections, citizen science records and public databases used in the formulation of species distribution maps, but also for other downstream analyses that rely on these datasets.

Microcins are peptide antibiotics secreted by Gram-negative bacteria that inhibit the growth of neighboring microbes. They are exported from the cytosol to the environment in a one-step process through a specific type I secretion system (T1SS). While the rules governing export of natural or non-native substrates have been resolved for T1SSs that secrete large proteins, relatively little is known about substrate requirements for peptides exported through T1SSs that secrete microcins. Here, we investigate the prototypic microcin V T1SS fromEscherichia coliand show it can export a remarkably wide range of natural and synthetic peptides. We demonstrate that secretion through this system is not affected by peptide charge or hydrophobicity and appears only constrained by peptide length. A varied range of bioactive peptides, including an antibacterial peptide, a microbial signaling factor, a protease inhibitor, and a human hormone, can all be secreted and elicit their intended biological effect. Secretion through this system is not limited toE. coli, and we demonstrate its function in additional Gram-negative species that can inhabit the gastrointestinal tract. Our findings uncover the highly promiscuous nature of peptide export thorough the microcin V T1SS, which has implications for native cargo capacity and use of Gram-negative bacteria for peptide research and delivery.ImportanceMicrocin type I secretion systems in Gram-negative bacteria transport antibacterial peptides from the cytoplasm to the extracellular environment in single step. In nature, each microcin secretion system is generally paired with a specific peptide. We know little about the export capacity of these transporters and how peptide sequence influences secretion. Here, we investigate the microcin V type I secretion system. Remarkably, our studies show this system can export diverse peptides and is only limited by peptide length. Furthermore, we demonstrate that various bioactive peptides can be secreted, and this system can be used in Gram-negative species that colonize the gastrointestinal tract. These finding expand our understanding of secretion through type I systems and their potential uses in peptide applications.

Pachydactylus is the most species-rich reptile genus in southern Africa. Most species are habitat specialists adapted to hyper-arid conditions of the Namibian and north-western South African xeric regions. Although a fair number of phylogenetic studies and taxonomic revisions have been published, some species still remain rather enigmatic. In the ten years since the taxonomic revision of the weberi group, some of the species have not been recorded and our knowledge on their distribution, phylogenetic affinities, or intraspecific variability is limited or non-existent. Pachydactylus goodi is one such species. In this study, we report a newly discovered population of P. goodi in the Richtersveld National Park, South Africa, which considerably extends the known range of the species. In addition, the results of our phylogenetic analyses indicate that P. goodi is paraphyletic with respect to P. atorquatus. Although there is a striking colour polymorphism observed between these two species, the level of genetic differentiation within the goodi-atorquatus clade is comparable with intraspecific variability observed in other Pachydactylus species. As a result of these findings, which are further supported by morphological similarity of the two species, we conclude that they represent a single species and synonymise P. goodi with P. atorquatus.

Large laser systems that deliver optical pulses with peak powers exceeding one Petawatt (PW) have been constructed at dozens of research facilities worldwide and have fostered research in High-Energy-Density (HED) Science, High-Field and nonlinear physics [1]. Furthermore, the high intensities exceeding 1018W/cm2 allow for efficiently driving secondary sources that inherit some of the properties of the laser pulse, e.g. pulse duration, spatial and/or divergence characteristics. In the intervening decades since that first PW laser, single-shot proof-of-principle experiments have been successful in demonstrating new high-intensity laser-matter interactions and subsequent secondary particle and photon sources. These secondary sources include generation and acceleration of charged-particle (electron, proton, ion) and neutron beams, and x-ray and gamma-ray sources, generation of radioisotopes for positron emission tomography (PET), targeted cancer therapy, medical imaging, and the transmutation of radioactive waste [2, 3]. Each of these promising applications requires lasers with peak power of hundreds of terawatt (TW) to petawatt (PW) and with average power of tens to hundreds of kW to achieve the required secondary source flux.

Hundred-joule, kilowatt-class lasers based on diode-pumped solid-state technologies, are being developed worldwide for laser-plasma interactions and as prototypes for fusion energy drivers. The goal of the Mercury Laser Project is to develop key technologies within an architectural framework that demonstrates basic building blocks for scaling to larger multi-kilojoule systems for inertial fusion energy (IFE) applications. Mercury has requirements that include: scalability to IFE beamlines, 10 Hz repetition rate, high efficiency, and 10 9 shot reliability. The Mercury laser has operated continuously for several hours at 55 J and 10 Hz with fourteen 4 x 6 cm 2 ytterbium doped strontium fluoroapatite amplifier slabs pumped by eight 100 kW diode arrays. A portion of the output 1047 nm was converted to 523 nm at 160 W average power with 73% conversion efficiency using yttrium calcium oxy-borate (YCOB).

Industrial and Scientific High Energy Laser Systems with output energies in the Joule to Megajoule range typically rely on flash lamps to energize the gain media. Especially in rep rated laser systems the advantage of low capital cost per lamp is outweighed by many disadvantages, such as low pump efficiency, heating of the gain medium, frequent maintenance requirement, significant capital cost for its pulsed power system, and laser performance stability. Diode Pumped Solid State Laser (DPSSL) systems represent a viable alternative. In this paper we will present an efficient, integrated power conditioning system developed for the High-Repetition-Rate Advanced Petawatt Laser System (HAPLS) that is being developed by LLNL for deployment in the international user facility Extreme Light Infrastructure Beamlines (ELI-Beamlines) in Czech Republic [1]. The High Energy Pump Laser of HAPLS is energized by 4 High Peak Power Laser Diode Arrays with total peak power of 3.2 MW that were developed by Lasertel and LLNL. The diode arrays deliver ∼1kJ at repetition rate 10Hz. Each diode array is comprised of 40 individual diode tiles where every tile generates >20 kilowatts of peak power. Each tile is driven by a single pulser that contains its own energy storage, control and high current drive circuitry. As part of the HAPLS laser the pulsers are operated at approximately 520A, a pulse width of 300μs at 10Hz. In another LLNL laser system basically identical pulsers are operated at 315A, 300us at 120Hz. The pulsers were designed to be operated in a support frame called a pulser crate. Each crate is designed to hold up to 45 pulsers in a volume similar to a desktop computer. Communication with the pulsers is by means of a one-way digital optical link which greatly simplifies the internal wiring. Each crate contains a “Brain Box” which in turn contains the front end processor (FEP), machine safety system (MSS) and energy storage dump subsystems. Providing flexibility and system balancing capability each pulser can be tailored to the diode tile: it has an internal Arbitrary Waveform Generator (AWG) on board that controls the shape of the diode current pulse. The AWG can vary the pulse shape in any combination of programmable increments with resolutions 1A and 1μs up to maximums of 1kA and 350μs. Under command of the crate controller each pulser can create its own distinct waveform and deliver that waveform when triggered.

Operation of the Mercury laser with two amplifiers has yielded 30 Joules at 1 Hz and 12 Joules at 10 Hz with over 8x10{sup 4} shots on the system. Static distortions in the Yb:S-FAP amplifiers were corrected by a magneto-rheological finishing technique.

Hepatozoon polytopis, described from Coluber constrictor priapus from Palm Beach County, Florida, has short, usually broad gamonts 12.8 x 4.6 microm (10.0-15.0 x 3.5-6.0), with LW 58.5 microm2 (42-84) and L/W 2.84 (1.8-3.7). Nuclei commonly extend into first quarter of gamont (45%), are always present in second quarter, and seldom in third quarter (11%), with dimensions 4.5 x 3.4 (3.0-6.0 x 2.5-4.5) and LW 15.1 (10.0-24.0). Spherical to ovoid oocysts, 122.1 x 104.9 (62-240 x 57-190), with L/W 1.17 (1.0-1.9), contain 31.3 (3-103) sporocysts. Spherical to ovoid sporocysts, 38.0 x 33.9 (28-73 x 25-58), with LW 1,325.1 (756-4,168) and L/W 1.12 (1.0-1.4), contain 42.9 (22-64) sporozoites. Thamnophis sauritus sackenii from Palm Beach County is infected also by H. polytopis, as indicated from similar gamont dimensions and verified by isolation of an identical haplotype of the 18S ribosomal RNA gene from both host species.

Hepatozoon guttata n. sp. is described from the corn snake (Elaphe guttata guttata) from south Florida. Gamonts average 14.6 x 4.6 (13-17 x 3.5-6) and are not recurved, with nucleus situated in the second quarter of the gamont. Erythrocyte cytoplasm rarely appears partially dehemoglobinized. The infected cells are usually distorted and are longer than the uninfected erythrocytes but do not differ in width; nuclei are smaller in length and width than those of uninfected cells. Sporogony in Aedes aegypti occurs within the head and the thorax but rarely in the abdomen. Oocysts are spherical to usually ovoid, 87.2 x 75.9 (45-155 x 40-152.5) and contain on average 7.1 (2-32) sporocysts. Sporocysts are spherical to ovoid, 34.8 x 31.0 (20-55 x 17.5-47.5), with 45.7 (14-89) sporozoites contained within. The pigmy rattlesnake (Sistrurus miliarius barbouri) in south Florida is parasitized by H. sistruri n. sp. Gamonts average 14.1 x 5.6 (12.6-15.8 x 4.7-6.3) in breadth and are not recurved, with the nucleus always situated in the second quarter of the gamont commonly at the midbody. Erythrocyte cytoplasm is not dehemoglobinized. The infected cells are always distorted and similar in length to the uninfected cells but with greater width and enlarged nuclei. Sporogony in A. aegypti occurs within head, thorax, and abdomen. Oocysts are spherical to usually ovoid, 163.6 x 154.7 (92-245 x 82-240) and contain 27.4 (12-42) sporocysts. Sporocysts are round to usually ovoid, 39.7 x 33.5 (25-50 x 20-50), with 45.7 (19-70) sporozoites.

The specific diagnosis of babesiosis, which is caused by the piroplasm Babesia microti, is made by microscopic identification of the organism in Giemsa-stained thin blood smears, detection of babesial antibody in acute-and convalescent-phase sera, or identification of the organism following the injection of patient blood into laboratory animals. Although rapid diagnosis can be made with thin blood smears, parasites are often not visualized early in the course of infection. PCR is a new, rapid diagnostic technique for the detection of Babesia spp. that has not yet been systematically evaluated. We conducted a blinded study of the sensitivity, specificity, and reproducibility of the PCR-based test with patients with babesiosis and a group of asymptomatic subjects residing in a region in southern New England where babesiosis is enzootic. Among 19 patients with recent babesial illness, we found that PCR was as sensitive and specific as the use of Giemsa-stained blood smears and inoculation of hamsters. Among asymptomatic subjects, the PCR result was positive for 3 persons with recent babesial infection and was negative for 41 persons without previous babesial infection. We conclude that the B. microti PCR procedure is sufficiently sensitive, specific, and reproducible for use in the diagnosis of acute babesiosis.

The scope of the Mercury Laser project encompasses the research, development, and engineering required to build a new generation of diode-pumped solid-state lasers for Inertial Confinement Fusion (ICF). The Mercury Laser will be the first integrated demonstration of laser diodes, crystals, and gas cooling within a scalable laser architecture. This report is intended to summarize the progress accomplished during the first three years of the project. Due to the technological challenges associated with production of 900 nm diode-bars, heatsinks, and high optical-quality Yb:S-FAP crystals, the initial focus of the project was primarily centered on the R&D in these three areas. During the third year of the project, the R&D continued in parallel with the development of computer codes, partial activation of the laser, component testing, and code validation where appropriate.

We report on the progress in developing and building the Mercury laser system as the first in a series of a new generation of diode- pumped solid-state Inertial Confinement Fusion (ICF) lasers at Lawrence Livermore National Laboratory (LLNL). Mercury will be the first integrated demonstration of a scalable laser architecture compatible with advanced high energy density (HED) physics applications. Primary performance goals include 10% efficiencies at 10 Hz and a 1-10 ns pulse with 1 omega energies of 100 J and with 2 omega/3 omega frequency conversion.

We present the results of performance modeling of diode-pumped solid state laser beamlines designed for use in Laser Inertial Fusion Energy (LIFE) power plants. Our modeling quantifies the efficiency increases that can be obtained by increasing peak diode power and reducing pump-pulse duration, to reduce decay losses. At the same efficiency, beamlines that use laser slabs of Yb:YAG or Yb:S-FAP require lower diode power than beamlines that use laser slabs of Nd:phosphate glass, since Yb:YAG and Yb:S-FAP have longer storage lifetimes. Beamlines using Yb:YAG attain their highest efficiency at a temperature of about 200K. Beamlines using Nd:phosphate glass or Yb:S-FAP attain high efficiency at or near room temperature.

The x-ray streak camera and x-ray framing camera for the National Ignition Facility were redesigned to improve electromagnetic pulse hardening, protect high voltage circuits from pressure transients, and maximize the use of common parts and operational software. Both instruments use the same PC104 based controller, interface, power supply, charge coupled device camera, protective hermetically sealed housing, and mechanical interfaces. Communication is over fiber optics with identical facility hardware for both instruments. Each has three triggers that can be either fiber optic or coax. High voltage protection consists of a vacuum sensor to enable the high voltage and pulsed microchannel plate phosphor voltage. In the streak camera, the high voltage is removed after the sweep. Both rely on the hardened aluminum box and a custom power supply to reduce electromagnetic pulse/electromagnetic interference (EMP/EMI) getting into the electronics. In addition, the streak camera has an EMP/EMI shield enclosing the front of the streak tube.

A LIFE laser driver needs to be designed and operated which meets the rigorous requirements of the NIF laser system while operating at high average power, and operate for a lifetime of >30 years. Ignition on NIF will serve to demonstrate laser driver functionality, operation of the Mercury laser system at LLNL demonstrates the ability of a diode-pumped solid-state laser to run at high average power, but the operational lifetime >30 yrs remains to be proven. A Laser Technology test Facility (LTF) has been designed to specifically address this issue. The LTF is a 100-Hz diode-pumped solid-state laser system intended for accelerated testing of the diodes, gain media, optics, frequency converters and final optics, providing system statistics for billion shot class tests. These statistics will be utilized for material and technology development as well as economic and reliability models for LIFE laser drivers.

This paper presents results of a taxonomic investigation of the family Syrphidae of the order Diptera in Puerto Rico. A total of 58 species included in 11 genera are presently recorded as a result of synonymy, new records, and descriptions of the following four new species: Baccha ( Baccha ) martorelli, Baccha ( Ocyptamus ) medina, Baccha ( Baccha ) neoparvicornis and Baccha ( Ocyptamus ) vockerothi . Keys are given for the identification of the reported genera and for most of the recorded species.

Laser operations with two amplifiers activated produced 35 Joules at 1 Hz, 12 Joules at 10 Hz, and 8x104 total system shots. Static distortions in the Yb:S-FAP amplifiers were corrected by magneto rheological finishing technique.

Brief note on how and why certain insects are able to survive the harsh weather in North Dakota.