The LUX-ZEPLIN (LZ) experiment is a dark matter detector centered on a dual-phase xenon time projection chamber. We report searches for new physics appearing through few-keV-scale electron recoils, ...using the experiment’s first exposure of 60 live days and a fiducial mass of 5.5 t. The data are found to be
consistent with a background-only hypothesis, and limits are set on models for new physics including solar axion electron coupling, solar neutrino magnetic moment and millicharge, and electron couplings to galactic axionlike particles and hidden photons. Similar limits are set on weakly interacting massive
particle (WIMP) dark matter producing signals through ionized atomic states from the Migdal effect.
Following the first science results of the LUX-ZEPLIN (LZ) experiment, a dual-phase xenon time projection chamber operating from the Sanford Underground Research Facility in Lead, South Dakota, USA, ...we report the initial limits on a model-independent nonrelativistic effective field theory describing the complete set of possible interactions of a weakly interacting massive particle (WIMP) with a nucleon. These results utilize the same 5.5 t fiducial mass and 60 live days of exposure collected for the LZ spin-independent and spin-dependent analyses while extending the upper limit of the energy region of interest by a factor of 7.5 to 270 keV. No significant excess in this high energy region is observed. Using a profile-likelihood ratio analysis, we report 90% confidence level exclusion limits on the coupling of each individual nonrelativistic WIMP-nucleon operator for both elastic and inelastic interactions in the isoscalar and isovector bases. Published by the American Physical Society 2024
The LUX-ZEPLIN experiment recently reported limits on WIMP-nucleus interactions from its initial science run, down to 9.2 x 10–48 cm2 for the spin-independent interaction of a 36 GeV/c2 WIMP at 90% ...confidence level. In this paper, we present a comprehensive analysis of the backgrounds important for this result and for other upcoming physics analyses, including neutrinoless double-beta decay searches and effective field theory interpretations of LUX-ZEPLIN data. We confirm that the in-situ determinations of bulk and fixed radioactive backgrounds are consistent with expectations from the ex-situ assays. The observed background rate after WIMP search criteria were applied was (6.3 ± 0.5) x 10–5 events /keVee/kg/day in the low-energy region, approximately 60 times lower than the equivalent rate reported by the LUX experiment.
Searches for dark matter with liquid xenon time projection chamber experiments have traditionally focused on the region of the parameter space that is characteristic of weakly interacting massive ...particles, ranging from a few GeV / c 2 to a few TeV / c 2 . Models of dark matter with a mass much heavier than this are well motivated by early production mechanisms different from the standard thermal freeze-out, but they have generally been less explored experimentally. In this work, we present a reanalysis of the first science run of the LZ experiment, with an exposure of 0.9 tonne × yr , to search for ultraheavy particle dark matter. The signal topology consists of multiple energy deposits in the active region of the detector forming a straight line, from which the velocity of the incoming particle can be reconstructed on an event-by-event basis. Zero events with this topology were observed after applying the data selection calibrated on a simulated sample of signal-like events. New experimental constraints are derived, which rule out previously unexplored regions of the dark matter parameter space of spin-independent interactions beyond a mass of 10 17 GeV / c 2 . Published by the American Physical Society 2024
In the pages of her account books, Abigail Robinson, a single woman from a Newport, Rhode Island merchant family at the turn of the nineteenth century, represented the mundane tasks of domestic life ...as monetary transactions. With each stroke of her pen, she linked the ways and concerns of the market with the "women's work" performed by herself and by the women she employed, corresponded with, and cared for. This article explores each kind of transaction recorded in Abigail's account books—hiring servants, buying imported goods for family and friends, stewarding young relatives, and investing in paper securities—to illuminate the complex ways in which emotion, social obligation, and economic calculation intersected. Strikingly and explicitly, market transactions constructed social relationships and affective ties shaped economic transactions. Women such as Abigail Robinson led lives that were at once more profoundly embedded in market concerns than those of their colonial forebears and clearly different from the emerging ideal of the private, sheltered home. Forged in networks of work and exchange, a commercial consciousness served variously as complement and alternative to "domesticity" for middling and well-to-do free women.
The use of cytomegalovirus (CMV) as a vaccine vector to express antigens against multiple infectious diseases, including simian immunodeficiency virus, Ebola virus, plasmodium, and mycobacterium ...tuberculosis, in rhesus macaques has generated extraordinary levels of protective immunity against subsequent pathogenic challenge. Moreover, the mechanisms of immune protection have altered paradigms about viral vector-mediated immunity against ectopically expressed vaccine antigens. Further optimization of CMV-vectored vaccines, particularly as this approach moves to human clinical trials will be augmented by a more complete understanding of how CMV engenders mechanisms of immune protection. This review summarizes the particulars of the specific CMV vaccine vector that has been used to date (rhesus CMV strain 68-1) in relation to CMV natural history.
In 1770, tavernkeeper Abigail Stoneman called in her debts by flourishing a handful of playing cards before the Rhode Island Court of Common Pleas. Scrawled on the cards were the IOUs of drinkers ...whose links to Stoneman testified to women's paradoxical place in the urban economy of the late eighteenth and early nineteenth centuries. Stoneman did traditional women's work-boarding, feeding, cleaning, and selling alcohol-but her customers, like her creditors, underscore her connections to an expansive commercial society. These connections are central toThe Ties That Buy. Historian Ellen Hartigan-O'Connor traces the lives of urban women in early America to reveal how they used the ties of residence, work, credit, and money to shape consumer culture at a time when the politics of the marketplace was gaining national significance. Covering the period 1750-1820, the book analyzes how women such as Stoneman used and were used by shifting forms of credit and cash in an economy transitioning between neighborly exchanges and investment-oriented transactions. In this world, commerce reached into every part of life. At the hearths of multifamily homes, renters, lodgers, and recent acquaintances lived together and struck financial deals for survival. Landladies, enslaved washerwomen, shopkeepers, and hucksters sustained themselves by serving the mobile population. A new economic practice in America-shopping-mobilized hierarchical and friendly relationships into wide-ranging consumer networks that depended on these same market connections. Rhetoric emerging after the Revolution downplayed the significance of expanding female economic life in the interest of stabilizing the political order. But women were quintessential market participants, with fluid occupational identities, cross-class social and economic connections, and a firm investment in cash and commercial goods for power and meaning.
Juster and Hartigan-O'Connor discuss one of the more bizarre episodes in the history of northern evangelicalism: the "Angel Delusion" of 1806-1811, in which an entire community of Freewill Baptists ...of New England conversed regularly with an Angel of God and did his bidding.
"Adaptive" NK cells, characterized by FcRγ deficiency and enhanced responsiveness to Ab-bound, virus-infected cells, have been found in certain hCMV-seropositive individuals. Because humans are ...exposed to numerous microbes and environmental agents, specific relationships between hCMV and FcRγ-deficient NK cells (also known as g-NK cells) have been challenging to define. Here, we show that a subgroup of rhesus CMV (RhCMV)-seropositive macaques possesses FcRγ-deficient NK cells that stably persist and display a phenotype resembling human FcRγ-deficient NK cells. Moreover, these macaque NK cells resembled human FcRγ-deficient NK cells with respect to functional characteristics, including enhanced responsiveness to RhCMV-infected target in an Ab-dependent manner and hyporesponsiveness to tumor and cytokine stimulation. These cells were not detected in specific pathogen-free (SPF) macaques free of RhCMV and six other viruses; however, experimental infection of SPF animals with RhCMV strain UCD59, but not RhCMV strain 68-1 or SIV, led to induction of FcRγ-deficient NK cells. In non-SPF macaques, coinfection by RhCMV with other common viruses was associated with higher frequencies of FcRγ-deficient NK cells. These results support a causal role for specific CMV strain(s) in the induction of FcRγ-deficient NK cells and suggest that coinfection by other viruses further expands this memory-like NK cell pool.
Although quantitative identification and viable enrichment of natural regulatory T cells (T-regs) in humans are problematic, such steps would greatly facilitate the analysis of these cells in disease ...states. In an attempt to identify markers that are sensitive and specific for human T-regs, we analyzed the expression of fourteen intracellular and cell surface markers on human CD4
+ cells. Many markers were partially selective for CD25
hi T-regs, but consistent and specific discrimination of functional T-regs was only made possible by focus on CD127, the alpha chain of the IL-7 receptor. Although most CD4
+ human T cells express CD127, T-regs exhibiting suppressive activity
in vitro display distinctly lower surface expression of this marker, irrespective of their level of CD25 expression. Sorted cells with the surface phenotype CD4
+CD25
+CD127
low had higher levels of intracellular FOXP3 and CTLA-4 and, as determined by functional assays, were suppressive, hypoproliferative, and poorly responsive to TCR signaling. The CD4
+CD25
+CD127
low phenotype was also found to be characteristic of T-regs found in mice and in rhesus macaques. This surface phenotype should allow for quantitative studies of regulatory T cells in disease states as well as for enrichment of live regulatory T cells for functional analyses and/or expansion
in vitro.
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