PVI System Technology (United States)

ABSTRACTAs glyphosate-based herbicides, sold under the commercial name Roundup®, represent the most used herbicides in the world, contamination of the freshwater environment by glyphosate has become a widespread issue. In Italy, glyphosate was detected in half of the surface waters monitoring sites and its concentrations were higher than environmental quality standards in 24.5% of them. It can last from days to months in water, leading to exposure for aquatic organisms and specifically to amphibians’ larvae that develop in shallow water bodies with proven effects to development and behaviour. In this study, we tested the effects of a 96h exposure during embryonic development of marsh frog’s tadpoles to three ecologically relevant Roundup® Power 2.0 concentrations. As expected, given the low concentrations tested, no mortality was observed. Morphological measurements highlighted a reduction in the total length in tadpoles exposed to 7.6 mg a.e./L, while an increase was observed at lower concentrations of 0.7 and 3.1 mg a.e./L compared to control group. Tadpoles raised in 7.6 mg a.e./L also showed a smaller tail membrane than those raised in the control solution. Regarding behaviour, we tested tadpoles in two different sessions (Gosner stages 25 and 28/29) for lateralization, antipredator response and basal activity. Lower intensity of lateralization was detected in tadpoles raised at the highest Roundup® concentration in the first session of observation, while no significant difference among treatments was observed in the second one. In both sessions, effects of glyphosate embryonic exposure on antipredator response, measured as the proportional change in activity after the injection of tadpole-fed predator (Anax imperator) cue, were not detected. Tadpoles exposed during embryonic development to Roundup® exhibited lower basal activity than the control group, with the strongest reduction for the 7.6 mg a.e./L treatment. Our results reinforce the concern of glyphosate contamination impact on amphibians.

A novel robotic plasma magnetron mole with a 50 cm long cathode was designed, fabricated, and operated. The reason for this endeavor is to alleviate the problems of unacceptable resistive heating of stainless steel vacuum tubes in the BNL Relativistic Heavy Ion Collider (RHIC). The magnetron mole was successfully operated to copper coat an assembly containing a full-size, stainless steel, cold bore, RHIC magnet tubing connected to two types of RHIC bellows, to which two additional pipes made of RHIC tubing were connected. To increase the cathode lifetime, a movable magnet package was developed, and the thickest possible cathode was made, with a rather challenging target to substrate (de facto anode) distance of less than 1.5 cm. Achieving reliable steady state magnetron discharges at such a short cathode to anode gap was rather challenging, when compared to commercial coating equipment, where the target to substrate distance is 10's cm; 6.3 cm is the lowest experimental target to substrate distance found in the literature. Additionally, the magnetron developed during this project provides unique omni-directional uniform coating. The magnetron is mounted on a carriage with spring loaded wheels that successfully crossed bellows and adjusted for variations in vacuum tube diameter, while keeping the magnetron centered. Electrical power and cooling water were fed through a cable bundle. The umbilical cabling system is driven by a motorized spool. Excellent coating adhesion was achieved. Measurements indicated that well-scrubbed copper coating reduced secondary electron yield to 1, i.e., the problem of electron clouds can be eliminated. Room temperature RF resistivity measurement indicated that a 10 μm copper coated stainless steel RHIC tube has a conductivity close to that of pure copper tubing. Excellent coating adhesion was achieved. The device details and experimental results are described.

To rectify the problems of electron clouds observed in RHIC and unacceptable ohmic heating for superconducting magnets that can limit future machine upgrades, we started developing a robotic plasma deposition technique for $in-situ$ coating of the RHIC 316LN stainless steel cold bore tubes based on staged magnetrons mounted on a mobile mole for deposition of Cu followed by amorphous carbon (a-C) coating. The Cu coating reduces wall resistivity, while a-C has low SEY that suppresses electron cloud formation. Recent RF resistivity computations indicate that 10 {\mu}m of Cu coating thickness is needed. But, Cu coatings thicker than 2 {\mu}m can have grain structures that might have lower SEY like gold black. A 15-cm Cu cathode magnetron was designed and fabricated, after which, 30 cm long samples of RHIC cold bore tubes were coated with various OFHC copper thicknesses; room temperature RF resistivity measured. Rectangular stainless steel and SS discs were Cu coated. SEY of rectangular samples were measured at room; and, SEY of a disc sample was measured at cryogenic temperatures.

A joint research and development of steady state intense boron ion sources for hundreds of electron-volt ion implanters has been in progress for the past 5 years. The difficulties of extraction and transportation of low energy boron beams can be solved by implanting clusters of boron atoms. In Institute for Theoretical and Experimental Physics (ITEP) the Bernas ion source successfully generated the beam of decaborane ions. The carborane (C(2)B(10)H(12)) ion beam is more attractive material due to its better thermal stability. The results of carborane ion beam generation are presented. The result of the beam implantation into the silicon wafer is presented as well.

Although HIV-associated neurocognitive disorders should be treated with highly active antiretroviral treatment (HAART) regimens with good central nervous system (CNS) penetration, the definition of neuroactive HAART remains controversial. We compared 2 ranking systems to measure HAART neuroeffectiveness. Patients with (n = 93) or at risk for (n = 92) HIV-associated neurocognitive disorders underwent neuropsychological (NP) test batteries before HAART initiation and at follow-up. Changes in normatively adjusted summary NP test z scores were calculated for each subject. Two neuropenetration scores were calculated: the central nervous system penetration reference score (number of drugs in the combination among zidovudine, abacavir, stavudine, lamivudine, efavirenz, nevirapine, indinavir, and lopinavir-ritonavir) and the CNS penetration-effectiveness (CPE) score: a summary score of 1 (high: penetration: [corrected] zidovudine, abacavir, delavirdine, [corrected] nevirapine, amprenavir-ritonavir, fosamprenavir-ritonavir, [corrected] indinavir-ritonavir, and lopinavir-ritonavir), 0.5 (intermediate penetration: [corrected] stavudine, lamivudine, emtricitabine, efavirenz, amprenavir, fosamprenavir, [corrected] atazanavir-ritonavir, atazanavir, [corrected] and indinavir), and 0 (low penetration: remaining ARVs) [corrected] for each drug in the combination. Main outcome measures were changes in global NPZ scores and in summary z scores on 5 domains. At regression analyses, higher CPE scores correlated with greater improvements in NPZ-4 (P = 0.0283), NPZ-8 (P = 0.0071), concentration and speed of mental processing (P = 0.0046), and mental flexibility (P = 0.0262) summary z scores. The correlation was stronger among NP-impaired patients. By contrast, higher estimates of neuroeffectiveness with the alternative system showed no correlation. No association was seen between CD4 and plasma viral load changes with both scores. The CPE score represents a step forward toward the identification of a clinically useful approach to estimating HAART ability to improve cognition.

A joint research and development effort whose ultimate goal is to develop an intense, high charge state, ion source for mega-electron-volt ion implanters has been initiated. Present day high-energy ion implanters utilize low charge state (usually single charge) ion sources in combination with radio frequency (rf) accelerators. Usually, a MeV Linear Accelerator (MV LINAC) is used for acceleration of a few milliamperes. It is desirable to have instead an intense, high charge state ion source on a relatively low energy platform [direct current (dc) acceleration] to generate high-energy ion beams for implantation. This endeavor is a continuation of earlier research, which resulted in generating ions like Pb+7 and Bi+8 and ion currents exceeding 200 mA. The natural next step is to convert and optimize ion charge state enhancement techniques to generate B, P, As, and Sb ions, and adapt them to a dc implanter. A number of schemes are to be pursued simultaneously. The most promising approach is to be developed into a commercial ion source.