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Despite being listed as endangered, substantial morphological and behavioral variation exists within Black-capped Petrel (Pterodroma hasitata) populations. To examine the population genetic structure of the Black-capped Petrel, we amplified Cytochrome Oxidase 1 sequences from museum specimens collected during 1970–1980 off the coast of North Carolina, USA. These sequences revealed a 1.2% fixed genetic difference between dark and light morphs. Individuals with intermediate plumage all grouped phylogenetically with the light morph. Combined with significant differences in body size and phenology, our genetic results suggest breeding isolation of the dark and light morphs. Consistent with other Pterodroma species, our results imply that the Black-capped Petrel may comprise two distinct, reproductively isolated taxa. Further knowledge about the genetic identity of birds at specific nesting colonies will be valuable for geographic delineation of populations.

The magnitude of growth in “underlying” wage inequality in the United States during the 1980s is obscured by a concurrent decline in the federal minimum wage, which itself could cause an increase in observed wage inequality. This study uses regional variation in the relative level of the federal minimum wage to separately identify the impact of the minimum wage from nationwide growth in “latent” wage dispersion during the 1980s. The analysis suggests that the minimum wage can account for much of the rise in dispersion in the lower tail of the wage distribution, particularly for women.

Dual blockade of PD-L1 and VEGF has enhanced anticancer immunity through multiple mechanisms and augmented antitumour activity in multiple malignancies. We aimed to assess the efficacy and safety of atezolizumab (anti-PD-L1) alone and combined with bevacizumab (anti-VEGF) in patients with unresectable hepatocellular carcinoma. GO30140 is an open-label, multicentre, multiarm, phase 1b study that enrolled patients at 26 academic centres and community oncology practices in seven countries worldwide. The study included five cohorts, and the two hepatocellular carcinoma cohorts, groups A and F, are described here. Inclusion criteria for these two groups included age 18 years and older; histologically, cytologically, or clinically (per American Association for the Study of Liver Diseases criteria) confirmed unresectable hepatocellular carcinoma that was not amenable to curative treatment; no previous systemic treatment; and Eastern Cooperative Oncology Group performance status of 0 or 1. In group A, all patients received atezolizumab (1200 mg) and bevacizumab (15 mg/kg) intravenously every 3 weeks. In group F, patients were randomly assigned (1:1) to receive intravenous atezolizumab (1200 mg) plus intravenous bevacizumab (15 mg/kg) every 3 weeks or atezolizumab alone by interactive voice-web response system using permuted block randomisation (block size of two) and stratification factors of geographical region; macrovascular invasion, extrahepatic spread, or both; and baseline α-fetoprotein concentration. Primary endpoints were confirmed objective response rate in all patients who received the combination treatment for group A and progression-free survival in the intention-to-treat population in group F, both assessed by an independent review facility according to Response Evaluation Criteria in Solid Tumors version 1.1. In both groups, safety was assessed in all patients who received at least one dose of any study treatment. This study is registered with ClinicalTrials.gov, NCT02715531, and is closed to enrolment. In group A, 104 patients were enrolled between July 20, 2016, and July 31, 2018, and received atezolizumab plus bevacizumab. With a median follow-up of 12·4 months (IQR 8·0–16·2), 37 (36%; 95% CI 26–46) of 104 patients had a confirmed objective response. The most common grade 3–4 treatment-related adverse events were hypertension (13 [13%]) and proteinuria (seven [7%]). Treatment-related serious adverse events occurred in 25 (24%) patients and treatment-related deaths in three (3%) patients (abnormal hepatic function, hepatic cirrhosis, and pneumonitis). In group F, 119 patients were enrolled and randomly assigned (60 to atezolizumab plus bevacizumab; 59 to atezolizumab monotherapy) between May 18, 2018, and March 7, 2019. With a median follow-up of 6·6 months (IQR 5·5–8·5) for the atezolizumab plus bevacizumab group and 6·7 months (4·2–8·2) for the atezolizumab monotherapy group, median progression-free survival was 5·6 months (95% CI 3·6–7·4) versus 3·4 months (1·9–5·2; hazard ratio 0·55; 80% CI 0·40–0·74; p=0·011). The most common grade 3–4 treatment-related adverse events in group F were hypertension (in three [5%] patients in the atezolizumab plus bevacizumab group; none in the atezolizumab monotherapy group) and proteinuria (in two [3%] patients in the atezolizumab plus bevacizumab group; none in the atezolizumab monotherapy group). Treatment-related serious adverse events occurred in seven (12%) patients in the atezolizumab plus bevacizumab group and two (3%) patients in the atezolizumab monotherapy group. There were no treatment-related deaths. Our study shows longer progression-free survival with a combination of atezolizumab plus bevacizumab than with atezolizumab alone in patients with unresectable hepatocellular carcinoma not previously treated with systemic therapy. Therefore, atezolizumab plus bevacizumab might become a promising treatment option for these patients. This combination is being compared with standard-of-care sorafenib in a phase 3 trial. F Hoffmann-La Roche/Genentech.

Unconventional superconductivity (SC) is said to occur when Cooper pair formation is dominated by repulsive electron–electron interactions, so that the symmetry of the pair wave function is other than an isotropic s-wave. The strong, on-site, repulsive electron–electron interactions that are the proximate cause of such SC are more typically drivers of commensurate magnetism. Indeed, it is the suppression of commensurate antiferromagnetism (AF) that usually allows this type of unconventional superconductivity to emerge. Importantly, however, intervening between these AF and SC phases, intertwined electronic ordered phases (IP) of an unexpected nature are frequently discovered. For this reason, it has been extremely difficult to distinguish the microscopic essence of the correlated superconductivity from the often spectacular phenomenology of the IPs. Here we introduce a model conceptual framework within which to understand the relationship between AF electron–electron interactions, IPs, and correlated SC. We demonstrate its effectiveness in simultaneously explaining the consequences of AF interactions for the copper-based, iron-based, and heavy-fermion superconductors, as well as for their quite distinct IPs.

One or two monovalent vaccine boosters showed a large decrease in neutralization activity against omicron subvariants. The BA.5-containing bivalent booster improved neutralizing activity against all omicron subvariants.

The defining characteristic 1 , 2 of Cooper pairs with finite centre-of-mass momentum is a spatially modulating superconducting energy gap Δ ( r ), where r is a position. Recently, this concept has been generalized to the pair-density-wave (PDW) state predicted to exist in copper oxides (cuprates) 3 , 4 . Although the signature of a cuprate PDW has been detected in Cooper-pair tunnelling 5 , the distinctive signature in single-electron tunnelling of a periodic Δ ( r ) modulation has not been observed. Here, using a spectroscopic technique based on scanning tunnelling microscopy, we find strong Δ ( r ) modulations in the canonical cuprate Bi 2 Sr 2 CaCu 2 O 8+ δ that have eight-unit-cell periodicity or wavevectors Q  ≈ (2π/ a 0 )(1/8, 0) and Q  ≈ (2π/ a 0 )(0, 1/8) (where a 0 is the distance between neighbouring Cu atoms). Simultaneous imaging of the local density of states N ( r ,  E ) (where E is the energy) reveals electronic modulations with wavevectors Q and 2 Q , as anticipated when the PDW coexists with superconductivity. Finally, by visualizing the topological defects in these N ( r ,  E ) density waves at 2 Q , we find them to be concentrated in areas where the PDW spatial phase changes by π, as predicted by the theory of half-vortices in a PDW state 6 , 7 . Overall, this is a compelling demonstration, from multiple single-electron signatures, of a PDW state coexisting with superconductivity in Bi 2 Sr 2 CaCu 2 O 8+ δ . Using a spectroscopic technique based on scanning tunnelling microscopy, the superconducting energy gap modulations in a copper oxide are visualized, demonstrating that a pair-density-wave state coexists with superconductivity.

SignificanceSurface states of topological insulators (TIs) should exhibit extraordinary electronic phenomena when a ‘Dirac-mass gap’ is opened in their spectrum, typically by creating a ferromagnetic state. However, our direct visualization of the Dirac-mass gap Δ(r) in a ferromagnetic TI reveals its intense disorder at the nanoscale. This is correlated with the density of magnetic dopant atoms n(r), such that Δ(r)∝n(r) as anticipated for surface-state–mediated ferromagnetism. Consequent new perspectives on ferromagnetic TI physics include that the quantum anomalous Hall effect occurs in this environment of extreme Dirac-mass disorder and that paths of associated chiral edge states must be tortuous. To achieve all the exotic physics expected of ferromagnetic TIs, greatly improved control of dopant-induced Dirac-mass gap disorder is therefore required. To achieve and use the most exotic electronic phenomena predicted for the surface states of 3D topological insulators (TIs), it is necessary to open a “Dirac-mass gap” in their spectrum by breaking time-reversal symmetry. Use of magnetic dopant atoms to generate a ferromagnetic state is the most widely applied approach. However, it is unknown how the spatial arrangements of the magnetic dopant atoms influence the Dirac-mass gap at the atomic scale or, conversely, whether the ferromagnetic interactions between dopant atoms are influenced by the topological surface states. Here we image the locations of the magnetic (Cr) dopant atoms in the ferromagnetic TI Cr0.08(Bi0.1Sb0.9)1.92Te3. Simultaneous visualization of the Dirac-mass gap Δ(r) reveals its intense disorder, which we demonstrate is directly related to fluctuations in n(r), the Cr atom areal density in the termination layer. We find the relationship of surface-state Fermi wavevectors to the anisotropic structure of Δ(r) not inconsistent with predictions for surface ferromagnetism mediated by those states. Moreover, despite the intense Dirac-mass disorder, the anticipated relationship Δ(r)∝n(r) is confirmed throughout and exhibits an electron–dopant interaction energy J* = 145 meV·nm2. These observations reveal how magnetic dopant atoms actually generate the TI mass gap locally and that, to achieve the novel physics expected of time-reversal symmetry breaking TI materials, control of the resulting Dirac-mass gap disorder will be essential.

Background. Until recently, Plasmodium knowlesi malaria in humans was misdiagnosed as Plasmodium malariae malaria. The objectives of the present study were to determine the geographic distribution of P. knowlesi malaria in the human population in Malaysia and to investigate 4 suspected fatal cases. Methods. Sensitive and specific nested polymerase chain reaction was used to identify all Plasmodium species present in (1) blood samples obtained from 960 patients with malaria who were hospitalized in Sarawak, Malaysian Borneo, during 2001–2006; (2) 54 P. malariae archival blood films from 15 districts in Sabah, Malaysian Borneo (during 2003–2005), and 4 districts in Pahang, Peninsular Malaysia (during 2004–2005); and (3) 4 patients whose suspected cause of death was P. knowlesi malaria. For the 4 latter cases, available clinical and laboratory data were reviewed. Results. P. knowlesi DNA was detected in 266 (27.7%) of 960 of the samples from Sarawak hospitals, 41 (83.7%) of 49 from Sabah, and all 5 from Pahang. Only P. knowlesi DNA was detected in archival blood films from the 4 patients who died. All were hyperparasitemic and developed marked hepatorenal dysfunction. Conclusions. Human infection with P. knowlesi, commonly misidentified as the more benign P. malariae, are widely distributed across Malaysian Borneo and extend to Peninsular Malaysia. Because P. knowlesi replicates every 24 h, rapid diagnosis and prompt effective treatment are essential. In the absence of a specific routine diagnostic test for P. knowlesi malaria, we recommend that patients who reside in or have traveled to Southeast Asia and who have received a “P. malariae” hyperparasitemia diagnosis by microscopy receive intensive management as appropriate for severe falciparum malaria.

To assess psychological effects of the initial peak phase of the COVID-19 pandemic on United States (US) medical students in clinical training to anticipate sequelae and prepare for future outbreaks. Authors emailed a cross-sectional survey in April-May, 2020 to students in clinical training years at six US medical schools which included validated General Anxiety Disorder (GAD-7) and Primary Care-PTSD (PC-PTSD-5) screening tools, and asked students about pandemic-related stress and specific concerns. Authors used quantitative and thematic analysis to present results. Of 2511 eligible students, 741 responded (29.5%). Most students (84.1%) reported at least \"somewhat\" increased levels of stress and anxiety related to the pandemic. On the GAD-7, 34.3% showed mild, 16.1% moderate, and 9.5% severe anxiety symptoms, with 39.6% demonstrating no/minimal symptoms. One quarter (25.4%) screened positive for PTSD risk symptoms. Top concerns of students chosen from a pre-populated list included inadequate COVID-19 testing, undiagnosed or asymptomatic spread and racial or other disparities in the pandemic. In thematic analysis, students' reactions to removal from clinical learning included: understanding the need to conserve PPE (32.2%), a desire to help (27.7%), worry over infectious risk to others (25.4%) and self (21.2%), and lost learning opportunities (22.5%). Female students were significantly more likely to report anxiety and PTSD risk symptoms. Asian students had a greater risk of moderate anxiety and those underrepresented in medicine (UIM) had greater risk of moderate and severe anxiety symptoms compared to white students. During the initial peak phase of COVID-19, over 60% of US medical students screened positive for pandemic-related anxiety and one quarter were at risk for PTSD. Female and UIM students were significantly more affected. Medical schools should consider broad support of students, and targeted outreach to female and UIM students.

If strong electron-electron interactions between neighboring Fe atoms mediate the Cooper pairing in iron-pnictide superconductors, then specific and distinct anisotropic superconducting energy gaps Δ j (K⃗) should appear on the different electronic bands i. Here, we introduce intraband Bogoliubov quasiparticle scattering interference (QPI) techniques for determination of Δ j (K⃗) in such materials, focusing on lithium iron arsenide (LiFeAs). We identify the three hole-like bands assigned previously as γ, α₂ and αⁱ, and we determine the anisotropy, magnitude, and relative orientations of their Δ j (K⃗). These measurements will advance quantitative theoretical analysis of the mechanism of Cooper pairing in iron-based superconductivity.