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Reopening of colleges and universities for the Fall semester of 2020 across the United States has caused significant COVID-19 case spikes, requiring reactive responses such as temporary closures and switching to online learning. Until sufficient levels of immunity are reached through vaccination, Institutions of Higher Education will need to balance academic operations with COVID-19 spread risk within and outside the student community. In this work, we study the impact of proximity statistics obtained from high resolution mobility traces in predicting case rate surges in university counties. We focus on 50 land-grant university counties (LGUCs) across the country and show high correlation (PCC > 0.6) between proximity statistics and COVID-19 case rates for several LGUCs during the period around Fall 2020 reopenings. These observations provide a lead time of up to 3 weeks in preparing resources and planning containment efforts. We also show how features such as total population, population affiliated with university, median income and case rate intensity could explain some of the observed high correlation. We believe these easily explainable mobility metrics along with other disease surveillance indicators can help universities be better prepared for the Spring 2021 semester. 

Parks are essential for protecting biodiversity and finding ways to improve park effectiveness is an important topic. We contributed to this debate by examining spatial and temporal changes in illegal activities in Kibale National Park, Uganda between 2006 and 2016 and used existing data to evaluate how the changes were correlated with the living conditions of people in neighboring communities, as well as patrolling effort. We explore the effectiveness of conservation strategies implemented in Kibale, by quantifying changes in the abundance of nine animal species over two to five decades. While uncertainty in such animal survey data are inherently large and it is hard to generalize across a 795‐km²area that encompasses diverse habitat types, data suggest an increase in animal abundance in the National Park. An increase in patrolling effort by park guards over the decade was correlated with a decline in the number of traps and snares found, which suggests patrolling helped limit resource extraction from the park. The park’s edge was extensively used for illegal forest product extraction, while the setting of snares occurred more often deeper in the forest. Perhaps counter‐intuitively, increased community wealth or park‐related employment in a village next to the park were positively correlated with increased illegal forest product extraction. Overall, our results suggest that the portfolio of conservation strategies used over the last two to five decades were effective for protecting the park and its animals, although understanding the impact of these efforts on local human populations and how to mitigate any losses and suffering they sustain remains an important area of research and action. It is evident that complex social, political and economic drivers impact conservation success and more interdisciplinary studies are required to quantify and qualify these dimensions.

 

Measurements of the$p_{\mathrm{T}}$-dependent flow vector fluctuations in Pb–Pb collisions at$\sqrt{s_{\mathrm{NN}}}=5.02\mathrm{TeV}$using azimuthal correlations with the ALICE experiment at the Large Hadron Collider are presented. A four-particle correlation approach [ALICE Collaboration, ] is used to quantify the effects of flow angle and magnitude fluctuations separately. This paper extends previous studies to additional centrality intervals and provides measurements of the$p_{\mathrm{T}}$-dependent flow vector fluctuations at$\sqrt{s_{\mathrm{NN}}}=5.02\mathrm{TeV}$with two-particle correlations. Significant$p_{\mathrm{T}}$-dependent fluctuations of the${\vec{V}}_2$flow vector in Pb–Pb collisions are found across different centrality ranges, with the largest fluctuations of up to$\sim 15\%$being present in the 5% most central collisions. In parallel, no evidence of significant$p_{\mathrm{T}}$-dependent fluctuations of${\vec{V}}_3$or${\vec{V}}_4$is found. Additionally, evidence of flow angle and magnitude fluctuations is observed with more than$5\sigma$significance in central collisions. These observations in$\text{Pb–Pb}$collisions indicate where the classical picture of hydrodynamic modeling with a common symmetry plane breaks down. This has implications for hard probes at high$p_{\mathrm{T}}$, which might be biased by$p_{\mathrm{T}}$-dependent flow angle fluctuations of at least 23% in central collisions. Given the presented results, existing theoretical models should be reexamined to improve our understanding of initial conditions, quark–gluon plasma properties, and the dynamic evolution of the created system.

A Large Ion Collider Experiment (ALICE) has been conceived and constructed as a heavy-ion experiment at the LHC. During LHC Runs 1 and 2, it has produced a wide range of physics results using all collision systems available at the LHC. In order to best exploit new physics opportunities opening up with the upgraded LHC and new detector technologies, the experiment has undergone a major upgrade during the LHC Long Shutdown 2 (2019–2022). This comprises the move to continuous readout, the complete overhaul of core detectors, as well as a new online event processing farm with a redesigned online-offline software framework. These improvements will allow to record Pb-Pb collisions at rates up to 50 kHz, while ensuring sensitivity for signals without a triggerable signature.

 

Recent measurements of charm-baryon production in hadronic collisions have questioned the universality of charm-quark fragmentation across different collision systems. In this work the fragmentation of charm quarks into charm baryons is probed, by presenting the first measurement of the longitudinal jet momentum fraction carried by${\mathrm{\Lambda }}_c^{+}$baryons,$z_{\parallel }^{\mathrm{ch}}$, in hadronic collisions. The results are obtained in proton-proton ($pp$) collisions at$\sqrt{s}=13\mathrm{TeV}$at the LHC, with${\mathrm{\Lambda }}_c^{+}$baryons and charged (track-based) jets reconstructed in the transverse momentum intervals of$3\le p_T^{{\mathrm{\Lambda }}_c^{+}}<15\mathrm{GeV}/c$and$7\le p_T^{\text{jet ch}}<15\mathrm{GeV}/c$, respectively. The$z_{\parallel }^{\mathrm{ch}}$distribution is compared to a measurement of${\mathrm{D}}^0$-tagged charged jets in$pp$collisions as well as to 8 simulations. The data hints that the fragmentation of charm quarks into charm baryons is softer with respect to charm mesons, in the measured kinematic interval, as predicted by hadronization models which include color correlations beyond leading-color in the string formation.

© 2024 CERN, for the ALICE Collaboration2024CERN 

The first measurement of the cross section for incoherent photonuclear production of$J/\psi$vector mesons as a function of the Mandelstam$|t|$variable is presented. The measurement was carried out with the ALICE detector at midrapidity,$|y|<0.8$, using ultraperipheral collisions of Pb nuclei at a center-of-mass energy per nucleon pair of$\sqrt{s_{\mathrm{NN}}}=5.02\mathrm{TeV}$. This rapidity interval corresponds to a Bjorken-$x$range$(0.3–1.4)\times {10}^{-3}$. Cross sections are given in five$|t|$intervals in the range$0.04<|t|<1{\mathrm{GeV}}^2$and compared to the predictions by different models. Models that ignore quantum fluctuations of the gluon density in the colliding hadron predict a$|t|$dependence of the cross section much steeper than in data. The inclusion of such fluctuations in the same models provides a better description of the data.

© 2024 CERN, for the ALICE Collaboration2024CERN