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The design of an effective AIDS vaccine has eluded the efforts of the scientific community to the point that alternative approaches to classic vaccine formulations have to be considered. We propose here that HIV vaccine research could greatly benefit from the study of natural simian immunodeficiency virus (SIV) infections of African nonhuman primates. Natural SIV hosts (for example, sooty mangabeys, African green monkeys and mandrills) share many features of HIV infection of humans; however, they usually do not develop immunodeficiency. These natural, nonprogressive SIV infections represent an evolutionary adaptation that allows a peaceful coexistence of primate lentiviruses and the host immune system. This adaptation does not result in reduced viral replication but, rather, involves phenotypic changes to CD4 + T cell subsets, limited immune activation and preserved mucosal immunity, all of which contribute to the avoidance of disease progression and, possibly, to the reduction of vertical SIV transmission. Here we summarize the current understanding of SIV infection of African nonhuman primates and discuss how unraveling these evolutionary adaptations may provide clues for new vaccine designs that might induce effective immune responses without the harmful consequences of excessive immune activation.

Exploiting the weak interactions between electron spins and nuclear spins in silicon-based quantum dots leads to a dephasing time two orders of magnitude greater than in analogous gallium-arsenide-based devices, demonstrating the potential of silicon as a host material for quantum information processing. Silicon chips make quantum leap Silicon is the established platform for microelectronics, and may yet fulfill a similar role for quantum technologies. Standard fabrication techniques already allow the isolation of single electron spins in silicon transistor-like devices, and these single spins can be used as quantum bits, or qubits. Unfortunately, such qubits tend to lose their information quickly as a result of interaction between electron and nuclear spins. Here Maune et al . demonstrate a coherently controlled silicon-based qubit that contains far fewer nuclear spins and achieves much longer quantum memory times. Used in combination with fast qubit initialization and read-out, such devices could pave the way towards practical silicon-based quantum information processing . Silicon is more than the dominant material in the conventional microelectronics industry: it also has potential as a host material for emerging quantum information technologies. Standard fabrication techniques already allow the isolation of single electron spins in silicon transistor-like devices. Although this is also possible in other materials, silicon-based systems have the advantage of interacting more weakly with nuclear spins. Reducing such interactions is important for the control of spin quantum bits because nuclear fluctuations limit quantum phase coherence, as seen in recent experiments in GaAs-based quantum dots 1 , 2 . Advances in reducing nuclear decoherence effects by means of complex control 3 , 4 , 5 still result in coherence times much shorter than those seen in experiments on large ensembles of impurity-bound electrons in bulk silicon crystals 6 , 7 . Here we report coherent control of electron spins in two coupled quantum dots in an undoped Si/SiGe heterostructure and show that this system has a nuclei-induced dephasing time of 360 nanoseconds, which is an increase by nearly two orders of magnitude over similar measurements in GaAs-based quantum dots. The degree of phase coherence observed, combined with fast, gated electrical initialization, read-out and control, should motivate future development of silicon-based quantum information processors.

Antiretroviral therapy for HIV infection needs lifelong access and strict adherence to regimens that are both expensive and associated with toxic effects. A curative intervention will be needed to fully stop the epidemic. The failure to eradicate HIV infection during long-term antiretroviral therapy shows the intrinsic stability of the viral genome in latently infected CD4T cells and other cells, and possibly a sustained low-level viral replication. Heterogeneity in latently infected cell populations and homoeostatic proliferation of infected cells might affect the dynamics of virus production and persistence. Despite potent antiretroviral therapy, chronic immune activation, inflammation, and immune dysfunction persist, and are likely to have important effects on the size and distribution of the viral reservoir. The inability of the immune system to recognise cells harbouring latent virus and to eliminate cells actively producing virus is the biggest challenge to finding a cure. We look at new approaches to unravelling the complex virus–host interactions that lead to persistent infection and latency, and discuss the rationale for combination of novel treatment strategies with available antiretroviral treatment options to cure HIV.

Vaccine-induced cellular immunity controls virus replication in simian immunodeficiency virus (SIV)-infected monkeys only transiently, leading to the question of whether such vaccines for AIDS will be effective. We immunized monkeys with plasmid DNA and replication-defective adenoviral vectors encoding SIV proteins and then challenged them with pathogenic SIV. Although these monkeys demonstrated a reduction in viremia restricted to the early phase of SIV infection, they showed a prolonged survival. This survival was associated with preserved central memory CD4⁺ T lymphocytes and could be predicted by the magnitude of the vaccine-induced cellular immune response. These immune correlates of vaccine efficacy should guide the evaluation of AIDS vaccines in humans.

Recent decades have drawn more attention to the United States' treatment of Japanese Americans during World War II. Few people realize, however, the extent of the country's relocation, internment, and repatriation of German and Italian Americans, who were interned in greater numbers than Japanese Americans. The United States also assisted other countries, especially in Latin America, in expelling \"dangerous\" aliens, primarily Germans. In Enemies among Us John E. Schmitz examines the causes, conditions, and consequences of America's selective relocation and internment of its own citizens and enemy aliens, as well as the effects of internment on those who experienced it. Looking at German, Italian, and Japanese Americans, Schmitz analyzes the similarities in the U.S. government's procedures for those they perceived to be domestic and hemispheric threats, revealing the consistencies in the government's treatment of these groups, regardless of race. Reframing wartime relocation and internment through a broader chronological perspective and considering policies in the wider Western Hemisphere, Enemies among Us provides new conclusions as to why the United States relocated, interned, and repatriated both aliens and citizens considered enemies.

The Omicron variant of SARS‐CoV‐2 achieved worldwide dominance in late 2021. Early work suggests that infections caused by the Omicron variant may be less severe than those caused by the Delta variant. We sought to compare clinical outcomes of infections caused by these two strains, confirmed by whole genome sequencing, over a short period of time, from respiratory samples collected from SARS‐CoV‐2 positive patients at a large medical center. We found that infections caused by the Omicron variant caused significantly less morbidity, including admission to the hospital and requirement for oxygen supplementation, and significantly less mortality than those caused by the Delta variant.

Background Cognitive models of post-traumatic stress disorder (PTSD) propose that trauma entails cognitive alterations of increased distrust and perceived threat from others. We tested whether these predictions also hold in individuals with varying levels of childhood maltreatment (CM), which is much more prevalent than traumatic events as required for a PTSD diagnosis. We hypothesized that higher levels of CM would entail greater distrust and perceived threat, and that distrust would be more change-resistant in participants with more CM. Methods The study was pre-registered; the pre-registration protocol, data, and code are available at https://osf.io/pufy2/ . We recruited 549 participants ( M age = 29.2, 74.5% women) for an online study via websites related to CM, Borderline Personality Disorder, and via snowball method on social media. Participants self-reported their level of CM on the childhood trauma questionnaire (CTQ). Next, they played two rounds of a hypothetical distrust game, indicating the perceived trustworthiness of avatars by way of estimating expected monetary deductions from them (i.e. higher amounts indicating greater distrust). After the first round, we provided participants with the feedback that very little money was taken from them. We expected those with more CM to be less responsive to the positive feedback and to adapt their estimates less in the subsequent round. Following the distrust game, participants completed an emotion rating task in which they rated the emotional expressions of 60 faces on a scale from ‘very negative’ to ‘very positive’. We included angry, fearful, and happy facial expressions, and expected individuals with higher CM levels to provide more negative ratings. We conducted linear mixed effects models with random intercepts for raters and stimuli (crossed), and modelled random slopes for all within-person predictors. Results As hypothesized, higher levels of CM were associated with higher levels of distrust and a weaker decrease in distrust following positive feedback. Further supporting our hypotheses, individuals with higher levels of CM showed more negatively shifted emotion ratings. Conclusions Increased distrust and perceived interpersonal threat following trauma, as proposed in cognitive models of PTSD, likely also apply to individuals with CM, following a dose-response relationship. We discuss clinical implications of considering any level of CM as a potentially relevant treatment-factor, even when a trauma-related disorder is not the main diagnosis, and propose future research avenues.

In previous studies, Propionibacterium acnes was cultured from intervertebral disc tissue of ~25% of patients undergoing microdiscectomy, suggesting a possible link between chronic bacterial infection and disc degeneration. However, given the prominence of P. acnes as a skin commensal, such analyses often struggled to exclude the alternate possibility that these organisms represent perioperative microbiologic contamination. This investigation seeks to validate P. acnes prevalence in resected disc cultures, while providing microscopic evidence of P. acnes biofilm in the intervertebral discs. Specimens from 368 patients undergoing microdiscectomy for disc herniation were divided into several fragments, one being homogenized, subjected to quantitative anaerobic culture, and assessed for bacterial growth, and a second fragment frozen for additional analyses. Colonies were identified by MALDI-TOF mass spectrometry and P. acnes phylotyping was conducted by multiplex PCR. For a sub-set of specimens, bacteria localization within the disc was assessed by microscopy using confocal laser scanning and FISH. Bacteria were cultured from 162 discs (44%), including 119 cases (32.3%) with P. acnes. In 89 cases, P. acnes was cultured exclusively; in 30 cases, it was isolated in combination with other bacteria (primarily coagulase-negative Staphylococcus spp.) Among positive specimens, the median P. acnes bacterial burden was 350 CFU/g (12 - ~20,000 CFU/g). Thirty-eight P. acnes isolates were subjected to molecular sub-typing, identifying 4 of 6 defined phylogroups: IA1, IB, IC, and II. Eight culture-positive specimens were evaluated by fluorescence microscopy and revealed P. acnes in situ. Notably, these bacteria demonstrated a biofilm distribution within the disc matrix. P. acnes bacteria were more prevalent in males than females (39% vs. 23%, p = 0.0013). This study confirms that P. acnes is prevalent in herniated disc tissue. Moreover, it provides the first visual evidence of P. acnes biofilms within such specimens, consistent with infection rather than microbiologic contamination.

In the framework of a 3-3-1 model with right-handed neutrinos and three scalar triplets we consider different spontaneous symmetry breaking patterns seeking for a non-linear realization of accidental symmetries of the model, which will produce physical Nambu–Goldstone (NG) bosons in the neutral scalar spectrum. We make a detailed study of the safety of the model concerning the NG boson emission in energy-loss processes which could affect the standard evolution of astrophysical objects. We consider the model with a Z2 symmetry, conventionally used in the literature, finding that in all of the symmetry breaking patterns the model is excluded. Additionally, looking for solutions for that problem, we introduce soft Z2-breaking terms in the scalar potential in order to remove the extra accidental symmetries and at the same time maintain the model as simple as possible. We find that there is only one soft Z2-breaking term that enables us to get rid of the problematic NG bosons.

Clinical evidence suggests that cellular immunity is involved in controlling human immunodeficiency virus-1 (HIV-1) replication. An animal model of acquired immune deficiency syndrome (AIDS), the simian immunodeficiency virus (SIV)-infected rhesus monkey, was used to show that virus replication is not controlled in monkeys depleted of CD8$^+$ lymphocytes during primary SIV infection. Eliminating CD8$^+$ lymphocytes from monkeys during chronic SIV infection resulted in a rapid and marked increase in viremia that was again suppressed coincident with the reappearance of SIV-specific CD8$^+$ T cells. These results confirm the importance of cell-mediated immunity in controlling HIV-1 infection and support the exploration of vaccination approaches for preventing infection that will elicit these immune responses.