Orders of Magnitude Improved Cyclotron-Mode Cooling for Nondestructive Spin Quantum Transition Spectroscopy with Single Trapped Antiprotons.

We demonstrate efficient subthermal cooling of the modified cyclotron mode of a single trapped antiproton and reach particle temperatures T_{+}=E_{+}/k_{B} below 200 mK in preparation times shorter than 500 s. This corresponds to the fastest resistive single-particle cyclotron cooling to subthermal temperatures ever demonstrated. By cooling trapped particles to such low energies, we demonstrate the detection of antiproton spin transitions with an error rate <0.000 023, more than 3 orders of magnitude better than in previous best experiments. This method has enormous impact on multi-Penning-trap experiments that measure magnetic moments with single nuclear spins for tests of matter and antimatter symmetry, high-precision mass spectrometry, and measurements of electron g factors bound to highly charged ions that test quantum electrodynamics and establish standards for magnetometry.

Image-Current Mediated Sympathetic Laser Cooling of a Single Proton in a Penning Trap Down to 170 mK Axial Temperature.

We demonstrate a new temperature record for image-current mediated sympathetic cooling of a single proton in a cryogenic Penning trap by laser-cooled ^{9}Be^{+}. An axial mode temperature of 170 mK is reached, which is a 15-fold improvement compared to the previous best value. Our cooling technique is applicable to any charged particle, so that the measurements presented here constitute a milestone toward the next generation of high-precision Penning-trap measurements with exotic particles.

Livedoid Vasculopathy with Severe Debilitating Neuropathy in a Prior Professional Athlete.

Livedoid vasculopathy (LV) can be a challenging diagnosis with an interesting pathophysiology. LV is an uncommon diagnosis that can be easily mistaken for more common skin conditions, especially in a person of color who may be underrepresented in pathology images used in medical education. LV has an average of five years from initial presentation to diagnosis, possibly due to providers not having it on their differential for lower extremity ulcerations. Prolonged time to diagnosis can potentially lead to life-changing complications. We present a case of a former professional sprinter who became debilitated by neuropathy secondary to complications from LV. He was seen multiple times and had an extensive work-up exploring a broad differential including autoimmune etiologies, hypercoagulable disorders, neuropathies, and other vascular disorders before reaching the diagnosis. This case emphasizes the importance of early diagnosis and treatment with a multidisciplinary team to help prevent the progression of these symptoms. We break down an extensive work-up that involves a multidisciplinary team including dermatology, hematology, neurology, rheumatology, and vascular surgery. This case will also highlight examples of LV in a patient with a dark skin complexion, which can be challenging to find in current literature. We additionally show images that demonstrate many of the classic pathologic findings associated with LV and how those can help lead to the diagnosis along with detailed descriptions of those findings. Classic physical exam findings including atrophic blanche and lower extremity ulcerations are highlighted. We also review LV's history, diagnosis, and treatment to help readers achieve a better understanding of the disease.

Trap-integrated fluorescence detection with silicon photomultipliers for sympathetic laser cooling in a cryogenic Penning trap.

We present a fluorescence-detection system for laser-cooled 9Be+ ions based on silicon photomultipliers (SiPMs) operated at 4 K and integrated into our cryogenic 1.9 T multi-Penning-trap system. Our approach enables fluorescence detection in a hermetically sealed cryogenic Penning-trap chamber with limited optical access, where state-of-the-art detection using a telescope and photomultipliers at room temperature would be extremely difficult. We characterize the properties of the SiPM in a cryocooler at 4 K, where we measure a dark count rate below 1 s-1 and a detection efficiency of 2.5(3)%. We further discuss the design of our cryogenic fluorescence-detection trap and analyze the performance of our detection system by fluorescence spectroscopy of 9Be+ ion clouds during several runs of our sympathetic laser-cooling experiment.

BASE-STEP: A transportable antiproton reservoir for fundamental interaction studies.

Currently, the world's only source of low-energy antiprotons is the AD/ELENA facility located at CERN. To date, all precision measurements on single antiprotons have been conducted at this facility and provide stringent tests of fundamental interactions and their symmetries. However, magnetic field fluctuations from the facility operation limit the precision of upcoming measurements. To overcome this limitation, we have designed the transportable antiproton trap system BASE-STEP to relocate antiprotons to laboratories with a calm magnetic environment. We anticipate that the transportable antiproton trap will facilitate enhanced tests of charge, parity, and time-reversal invariance with antiprotons and provide new experimental possibilities of using transported antiprotons and other accelerator-produced exotic ions. We present here the technical design of the transportable trap system. This includes the transportable superconducting magnet, the cryogenic inlay consisting of the trap stack and detection systems, and the differential pumping section to suppress the residual gas flow into the cryogenic trap chamber.

Ultra-thin polymer foil cryogenic window for antiproton deceleration and storage.

We present the design and characterization of a cryogenic window based on an ultra-thin aluminized biaxially oriented polyethylene terephthalate foil at T < 10 K, which can withstand a pressure difference larger than 1 bar at a leak rate <1×10-9 mbar l/s. Its thickness of ∼1.7 µm makes it transparent to various types of particles over a broad energy range. To optimize the transfer of 100 keV antiprotons through the window, we tested the degrading properties of different aluminum coated polymer foils of thicknesses between 900 and 2160 nm, concluding that 1760 nm foil decelerates antiprotons to an average energy of 5 keV. We have also explicitly studied the permeation as a function of coating thickness and temperature and have performed extensive thermal and mechanical endurance and stress tests. Our final design integrated into the experiment has an effective open surface consisting of seven holes with a diameter of 1 mm and will transmit up to 2.5% of the injected 100 keV antiproton beam delivered by the Antiproton Decelerator and Extra Low ENergy Antiproton ring facility of CERN.

BASE-high-precision comparisons of the fundamental properties of protons and antiprotons.

Abstract: The BASE collaboration at the antiproton decelerator/ELENA facility of CERN compares the fundamental properties of protons and antiprotons with ultra-high precision. Using advanced Penning trap systems, we have measured the proton and antiproton magnetic moments with fractional uncertainties of 300 parts in a trillion (p.p.t.) and 1.5 parts in a billion (p.p.b.), respectively. The combined measurements improve the resolution of the previous best test in that sector by more than a factor of 3000. Very recently, we have compared the antiproton/proton charge-to-mass ratios with a fractional precision of 16 p.p.t., which improved the previous best measurement by a factor of 4.3. These results allowed us also to perform a differential matter/antimatter clock comparison test to limits better than 3%. Our measurements enable us to set limits on 22 coefficients of CPT- and Lorentz-violating standard model extensions (SME) and to search for potentially asymmetric interactions between antimatter and dark matter. In this article, we review some of the recent achievements and outline recent progress towards a planned improved measurement of the antiproton magnetic moment with an at least tenfold improved fractional accuracy.

Extended pilot test of a cross-injection in situ denitrification system for pre-emptive treatment of municipal well water.

Elevated groundwater nitrate concentrations have been linked to deleterious health and environmental effects. A significant source of the nitrate is nitrogen fertilizers applied to agricultural landscapes. Beneficial Management Practices (BMPs), including the optimization of fertilizer use and selective crop rotations, have proven to be effective in some cases. The city of Woodstock in southern Ontario relies on public wells for all of its municipal supply. Several of the wells have experienced chronic increases in nitrate concentrations exceeding the maximum allowable limit of 10 mg/L N-NO3-. While BMPs are established, an interim reduction plan based on enhanced in situ denitrification (Cross Injection System, CIS) in a 15 m thick zone of high nitrate mass flux within the aquifer zone was evaluated. Based in the results of preliminary acetate injection experiments, a C:N ratio of 2.35, (approximately 260 mg acetate/L), was selected to optimize the denitrification reaction. Injections were performed for six hours a day every day for a period of approximately two months. Dissolved oxygen (DO) and nitrate concentrations recorded over time indicated that reduction of both commenced within a few days of the beginning of the acetate injections and reduced levels were maintained for the remainder of the two-month injection period. Denitrification occurred throughout the profile although nitrate reduction was the highest in the lower groundwater velocity zones. An overall reduction of nitrate of 50% was achieved through the treated section of the aquifer. It is estimated that an upscaled treatment system utilizing a treatment width of only 70 m would be sufficient to reduce the nitrate concentrations to below the drinking water limit demonstrating the potential for the CIS method to functions as an interim groundwater nitrate reduction strategy.

A high-Q superconducting toroidal medium frequency detection system with a capacitively adjustable frequency range >180 kHz.

We describe a newly developed polytetrafluoroethylene/copper capacitor driven by a cryogenic piezoelectric slip-stick stage and demonstrate with the chosen layout cryogenic capacitance tuning of ≈60 pF at ≈10 pF background capacitance. Connected to a highly sensitive superconducting toroidal LC circuit, we demonstrate tuning of the resonant frequency between 345 and 685 kHz, at quality factors Q > 100 000. Connected to a cryogenic ultra low noise amplifier, a frequency tuning range between 520 and 710 kHz is reached, while quality factors Q > 86 000 are achieved. This new device can be used as a versatile image current detector in high-precision Penning-trap experiments or as an LC-circuit-based haloscope detector to search for the conversion of axion-like dark matter to radio-frequency photons. This new development increases the sensitive detection bandwidth of our axion haloscope by a factor of ≈1000.

Molecular detection of two new putative species of gammaherpesvirus in petaurid possums.

A molecular survey of herpesviruses in Australian native mammals was conducted, spanning 260 individuals from 27 species. Among the herpesviruses detected, a putative new gammaherpesvirus species was detected in the yellow-bellied glider (Petaurus australis), and another in the critically endangered Leadbeater's possum (Gymnobelideus leadbeateri). In addition, the known host range of the putative species macropodid gammaherpesvirus 3 (MaHV-3) is herein extended to the western grey kangaroo (Macropus fuliginosus). These findings expand our understanding of herpesviruses in Australian mammals and may inform biosecurity protocols for captive and translocated populations.

A 16-parts-per-trillion measurement of the antiproton-to-proton charge-mass ratio.

The standard model of particle physics is both incredibly successful and glaringly incomplete. Among the questions left open is the striking imbalance of matter and antimatter in the observable universe1, which inspires experiments to compare the fundamental properties of matter/antimatter conjugates with high precision2-5. Our experiments deal with direct investigations of the fundamental properties of protons and antiprotons, performing spectroscopy in advanced cryogenic Penning trap systems6. For instance, we previously compared the proton/antiproton magnetic moments with 1.5 parts per billion fractional precision7,8, which improved upon previous best measurements9 by a factor of greater than 3,000. Here we report on a new comparison of the proton/antiproton charge-to-mass ratios with a fractional uncertainty of 16 parts per trillion. Our result is based on the combination of four independent long-term studies, recorded in a total time span of 1.5 years. We use different measurement methods and experimental set-ups incorporating different systematic effects. The final result, [Formula: see text], is consistent with the fundamental charge-parity-time reversal invariance, and improves the precision of our previous best measurement6 by a factor of 4.3. The measurement tests the standard model at an energy scale of 1.96 × 10-27 gigaelectronvolts (confidence level 0.68), and improves ten coefficients of the standard model extension10. Our cyclotron clock study also constrains hypothetical interactions mediating violations of the clock weak equivalence principle (WEPcc) for antimatter to less than 1.8 × 10-7, and enables the first differential test of the WEPcc using antiprotons11. From this interpretation we constrain the differential WEPcc-violating coefficient to less than 0.030.

Update on feline alphaherpesvirus-1 seroprevalence in Victorian feral and owned cats.

The seroprevalence of feline alphaherpesvirus-1 (FHV-1) in feral cats in Victoria, Australia, was last assessed in 1981 when serum-virus-neutralising antibodies (VNAb) against FHV-1 were detected in 11% of the sampled population from two Victorian locations. In this current study, VNAb were assessed in serum from feral cats located in Phillip Island, Point Cook and Hattah in the Mallee region in Northern Victoria. In feral cats, the seroprevalence of VNAb to FHV-1 was highest in Point Cook at 24.6% (17/69), followed by Phillip Island at 16.7% (11/66) and Hattah where no feral cats had detectable VNAb to FHV-1 (0/12). In contrast, virus-neutralising antibodies were observed in 84.1% (37/44) of Victorian-owned cats. This higher seroprevalence in owned cats is likely due to the use of FHV-1 vaccines; however, the vaccination history of the cats was not known and the development of neutralising antibodies after infection or vaccination can vary. The results are useful for understanding FHV-1 exposure in feral and owned cats and are important background information in the context of any potential future use of FHV-1-vectored vaccines.

Knowledge of pet-related zoonotic diseases and pet care in Hong Kong, a heavily crowded urban setting.

BACKGROUND: With the rapid expansion of pet animal populations worldwide, pet-related zoonotic diseases are becoming an important issue in public health. Hong Kong (HK), located in southern China, is one of the most crowded urban centres in the world. The population of pets, especially exotic pets, in HK has grown significantly in recent decades, potentially elevating the risk of pet-related zoonotic diseases. However, no studies have been conducted to explore the knowledge of HK public towards pet-related zoonotic diseases and animal husbandry practices. OBJECTIVES: To evaluate the level of awareness among the HK public of pet-related zoonotic diseases and their understanding of proper animal husbandry practices. METHODS: The study was carried out in HK from June-August 2019 using both online and paper versions of a questionnaire. A total of 362 completed questionnaires (74.3% return rate) were collected and the responses analysed. RESULTS: Sixty percent of the participants were current or past pet owners or planned on becoming pet owners in the coming 2 years, irrespective of their income or size of their living space. Among the participants, pet owners (including those who planned pet ownership) had a relatively higher level of awareness of pet-related zoonotic disease. However, the overall awareness of zoonotic diseases among both pet and non-pet owners was low with a knowledge score of <50%. A similar trend was observed for knowledge about proper animal husbandry practices. CONCLUSIONS: This study showed that the HK public was generally not familiar with pet-related zoonotic diseases and proper pet care. These knowledge gaps could potentially increase the risk of disease transmission. Further studies focusing on specific pet species and on people of different social-economic backgrounds are needed to provide future direction of efforts to reduce the risk of pet-related zoonotic diseases and to enhance pet-related animal and human welfare.

Topoisomerase I inhibition and peripheral nerve injury induce DNA breaks and ATF3-associated axon regeneration in sensory neurons.

Although axonal damage induces rapid changes in gene expression in primary sensory neurons, it remains unclear how this process is initiated. The transcription factor ATF3, one of the earliest genes responding to nerve injury, regulates expression of downstream genes that enable axon regeneration. By exploiting ATF3 reporter systems, we identify topoisomerase inhibitors as ATF3 inducers, including camptothecin. Camptothecin increases ATF3 expression and promotes neurite outgrowth in sensory neurons in vitro and enhances axonal regeneration after sciatic nerve crush in vivo. Given the action of topoisomerases in producing DNA breaks, we determine that they do occur immediately after nerve damage at the ATF3 gene locus in injured sensory neurons and are further increased after camptothecin exposure. Formation of DNA breaks in injured sensory neurons and enhancement of it pharmacologically may contribute to the initiation of those transcriptional changes required for peripheral nerve regeneration.

Sympathetic cooling of a trapped proton mediated by an LC circuit.

Efficient cooling of trapped charged particles is essential to many fundamental physics experiments1,2, to high-precision metrology3,4 and to quantum technology5,6. Until now, sympathetic cooling has required close-range Coulomb interactions7,8, but there has been a sustained desire to bring laser-cooling techniques to particles in macroscopically separated traps5,9,10, extending quantum control techniques to previously inaccessible particles such as highly charged ions, molecular ions and antimatter. Here we demonstrate sympathetic cooling of a single proton using laser-cooled Be+ ions in spatially separated Penning traps. The traps are connected by a superconducting LC circuit that enables energy exchange over a distance of 9 cm. We also demonstrate the cooling of a resonant mode of a macroscopic LC circuit with laser-cooled ions and sympathetic cooling of an individually trapped proton, reaching temperatures far below the environmental temperature. Notably, as this technique uses only image-current interactions, it can be easily applied to an experiment with antiprotons1, facilitating improved precision in matter-antimatter comparisons11 and dark matter searches12,13.