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Similarities and differences between hop cones and grape berries: sulfur and nitrogen aromas. A review. Introduction. Similarities can be found between the flavors of hop cones and grapes. The present paper will focus on their sulfur and nitrogen odorants. Literature. Although initially investigated in vines, recent research has led to the identification of a larger number of polyfunctional thiols in hop cones. These have included the pleasant-smelling grapefruit- or passion fruit-like 3-sulfanylhexan-1-ol. Surprisingly, to date, the occurrence of sulfides, polysulfides and thioesters (onion, vegetable or cheese-like flavors), as well as various thiophenes and terpenic episulfides has been described extensively only in the hop literature, while methoxypyrazines have been described only in vine cultivars. Conclusion. Among the sulfur and nitrogen odorants, many similarities have been observed between hop and grape polyfunctional thiols. Thiophenes, episulfides, sulfides, polysulfides and thioesters are mainly found in hop cones, while methoxypyrazines have been described only in grape.

Abstract Paleoclimate reconstructions from the Holocene are important for defining baseline conditions in order to interpret and contextualize the effects of modern climate change. Such records are particularly lacking for Siberia, a region that represents ~ 50% of the Arctic. In addition, the majority of proxy-based paleoclimate reconstructions for the Holocene represent mean annual conditions, and few quantify winter temperature, which is particularly important for predicting the effects of global warming in Arctic environments. Here we provide the first quantitative proxy reconstruction of precipitation and temperature for both summer and winter for 3000 years ago via novel high-resolution intra-annual carbon and oxygen isotope measurements across annual growth rings of fossil wood mummified within the permafrost of far northeastern Siberia. We found that the site experienced greater precipitation year-round (~ 10% increase in summer and ~ 30% increase in winter), cooler summer temperatures, and warmer winter temperatures, compared with today. Our findings indicate that warmer winter temperatures (+ 3.0 °C above early twentieth century values) in the Arctic 3000 years ago drove higher mean annual temperature by up to 1 °C, despite the existence of cooler summers, a similar phenomenon to what is observed within today’s Arctic environments, and past intervals of extreme global warmth.

A theory based on the demography of top management teams is used to explain membership turnover in two Swedish business groups, network analysis being used to define group membership. The results suggest these business groups possess a combination of financial and industrial experience as a group resource and the socialising strategy of control as a force counteracting the conflict-producing force of heterogeneity. An organisational demographic perspective focusing on opposing forces of heterogeneity and homogeneity is developed. It is shown that the perspective can be applied both to formal organisations and to informal ones such as networks.

Gold nanoparticles have been used as drug carriers and imaging reagents. The plant extract-capped gold nanoparticles provide better properties than chemically synthesized gold nanoparticles. In this study, Zingiber zerumbet extract-mediated green production of gold nanoparticles (Z. zerumbet@Au NPs) was established. Based on the UV-visible spectroscopy and transmission electron microscope (TEM) results, most Z. zerumbet@Au NPs were spherical. When more Z. zerumbet extracts were added, more spherical nanoparticles were formed. The hydrodynamic size changed slightly along with time, and the average size was approximately 170 nm. Capping of Z. zerumbet extract on the surface of gold nanoparticles was confirmed by Fourier transform infrared spectroscopy (FTIR). In general, phenolic compounds or flavonoid compounds were considered to be the reducing agent. However, zerumbone was identified as the reducing agent in this study. The resulting oxidized products were characterized by high-performance liquid chromatography-mass spectrometry (HPLC-MS). As a result, the solvent was proven to be involved in nanoparticle synthesis. Overall, Z zerumbet@Au NPs showed great potential to be used in cosmetic- or biomedicine-related fields.

Introduction. Dual-mobility (DM) implants for total hip arthroplasty (THA) have gained popularity due to their potential to reduce hip instability and dislocation events that may lead to revision surgery. These implants consist of a femoral head articulated within a polyethylene liner, which articulates within an outer acetabular shell, creating a dual-bearing surface. Our study aimed to report our observations on the survivorship of a novel DM implant for primary total hip arthroplasty at two years. Methods. We conducted a retrospective, multicenter study to assess the clinical outcomes of patients undergoing a THA with a novel DM implant (OR3O acetabular system™, Smith & Nephew, Inc., Memphis, TN) from January 2020 to September 2021. Patient demographics, surgical information, and survivorship data were collected from medical records for patients with a minimum of two years of follow-up. Primary outcomes included overall implant survivorship at two years as well as aseptic survivorship, revision rates of the DM acetabular shell, and average time to revision. Patient-reported outcomes were collected in the form of HOOS JR. Results. A total of 250 hips in 245 patients had a minimum two-year follow-up. Primary osteoarthritis (80%) was the most common indication for index THA. The average aseptic survivorship of the DM acetabular components at two years for the cohort was 98.4% and survivorship of the acetabular implants overall was 97.6%. There were a total of four (1.6%) aseptic revisions of the DM acetabular component. Reasons for aseptic acetabular revision included one case of instability, one intraprosthetic dislocation, one periprosthetic acetabular fracture, and one malpositioned acetabular cup resulting in impingement. The mean time of follow-up was 893.9 days. Eighty-seven patients had preoperative and two-year HOOS JR available. HOOS JR improved by an average of 38.5 points. Conclusion. This novel DM acetabular implant demonstrates excellent survivorship at two years follow-up with low rates of instability and intraprosthetic dislocation and no episodes of metal-on-metal corrosion. Use of the DM implant demonstrated clinically relevant improvements in patient-reported outcomes at two years.

A diverse group of RNA viruses have the ability to gain access to the central nervous system (CNS) and cause severe neurological disease. Current treatment for people with this type of infection is generally limited to supportive care. To address the need for reliable antivirals, we utilized a strategy of lethal mutagenesis to limit virus replication. We evaluated ribavirin (RBV), favipiravir (FAV) and N4-hydroxycytidine (NHC) against La Crosse virus (LACV), which is one of the most common causes of pediatric arboviral encephalitis cases in North America and serves as a model for viral CNS invasion during acute infection. NHC was approximately 3 to 170 times more potent than RBV or FAV in neuronal cells. Oral administration of molnupiravir (MOV), the prodrug of NHC, decreased neurological disease development (assessed as limb paralysis, ataxia and weakness, repeated seizures, or death) by 31% (4 mice survived out of 13) when treatment was started on the day of infection. MOV also reduced disease by 23% when virus was administered intranasally (IN). NHC and MOV produced less fit viruses by incorporating predominantly G to A or C to U mutations. Furthermore, NHC also inhibited virus production of two other orthobunyaviruses, Jamestown Canyon virus and Cache Valley virus. Collectively, these studies indicate that NHC/MOV has therapeutic potential to inhibit viral replication and subsequent neurological disease caused by orthobunyaviruses and potentially as a generalizable strategy for treating acute viral encephalitis. Author summary: Mutagenic ribonucleosides can be viewed as broadly acting antivirals against RNA viruses. These viruses have small genomes of essential genes and thus are susceptible to enhanced mutation rates as an antiviral strategy. Here we show that the mutagenic ribonucleoside N4-hydroxycytidine (NHC) and its prodrug molnupiravir are active against the negative strand bunyavirus La Crosse Virus. Loss of viral infectivity was proportional to the density of mutations induced by NHC. Using a mouse model, we showed that oral administration of molnupiravir attenuated encephalitis caused by La Crosse virus and resulted in reduced virus titers and less fit virus in the brain. This treatment approach should be widely applicable to acute RNA virus diseases, especially those with high morbidity and an absence of other treatment options. [ABSTRACT FROM AUTHOR]

Background The association between low-frequency human immunodeficiency virus type 1 (HIV-1) drug resistance mutations (DRMs) and treatment failure (TF) is controversial. We explore this association using next-generation sequencing (NGS) methods that accurately sample low-frequency DRMs. Methods We enrolled women with HIV-1 in Malawi who were either antiretroviral therapy (ART) naive (cohort A), had ART failure (cohort B), or had discontinued ART (cohort C). At entry, cohorts A and C began a nonnucleoside reverse transcriptase inhibitor–based regimen and cohort B started a protease inhibitor–based regimen. We used Primer ID MiSeq to identify regimen-relevant DRMs in entry and TF plasma samples, and a Cox proportional hazards model to calculate hazard ratios (HRs) for entry DRMs. Low-frequency DRMs were defined as ≤20%. Results We sequenced 360 participants. Cohort B and C participants were more likely to have TF than cohort A participants. The presence of K103N at entry significantly increased TF risk among A and C participants at both high and low frequency, with HRs of 3.12 (95% confidence interval [CI], 1.58–6.18) and 2.38 (95% CI, 1.00–5.67), respectively. At TF, 45% of participants showed selection of DRMs while in the remaining participants there was an apparent lack of selective pressure from ART. Conclusions Using accurate NGS for DRM detection may benefit an additional 10% of patients by identifying low-frequency K103N mutations. [ABSTRACT FROM AUTHOR]

Rare earth hafnates and zirconates are candidate materials for thermal and environmental barrier coatings (T/EBC) to protect gas turbine engine components from various environmental threats, including molten silicates derived from ingested mineral debris. This article examines the reactions of Gd2Hf2O7 (GHO) and Gd2Zr2O7 (GZO) to exemplary acidic and basic silicate melts. Exposure experiments at 1400°C reveal that both materials react to form mixed layers of apatite and fluorite. These layers largely hinder melt penetration of grain boundaries in GZO for exposures up to 4 h. However, extensive intergranular melt penetration occurs into GHO below the reaction layer within 1 h for the acidic melt and within 4 h for the basic melt. Shorter exposures (1–5 min) of Gd‐lean versions of the two compounds, viz. Gd0.2Hf0.8O1.9 and Gd0.2Zr0.8O1.9, are used to probe differences in the dissolution and diffusion rates. While both oxides form fluorite, the HfO2‐based one reacts more slowly than that based on ZrO2. Analysis of composition profiles across the solid/melt boundary reveals that Hf4+ diffuses more slowly than Zr4+ and that the hafnate dissolves more slowly than the zirconate; in both cases dissolution is diffusion‐controlled. The implications for the efficacy of reactive crystallization as a silicate mitigation strategy are discussed. [ABSTRACT FROM AUTHOR]

The generation of large spin currents, and the associated spin torques, which are at the heart of modern spintronics, has long been achieved by charge-to-spin conversion mechanisms, i.e., the spin Hall effect and/or the Rashba–Edelstein effect, intrinsically linked to strong spin–orbit coupling. Recently, a novel path has been predicted and observed for achieving significant current-induced torques originating from light elements, hence possessing weak spin–orbit interaction. These findings point out to the potential involvement of the orbital counterpart of electrons, namely the orbital Hall and orbital Rashba–Edelstein effects. In this study, we aim at quantifying these orbital-related contributions to the effective torques acting on a thin Co layer in different systems. First, we demonstrate in Pt|Co|Cu|AlOx stacking a comparable torque strength coming from the conversion due to the orbital Rashba–Edelstein effect at the Cu|AlOx interface and the one from the effective spin Hall effect in the bottom Pt|Co system. Second, in order to amplify the orbital-to-spin conversion, we investigate the impact of an intermediate Pt layer in Co|Pt|Cu|CuOx. From the Pt thickness dependence of the effective torques determined by harmonic Hall measurements complemented by spin Hall magneto-resistance and THz spectroscopy experiments, we demonstrate that a large orbital Rashba–Edelstein effect is present at the Cu|CuOx interface, leading to a twofold enhancement of the net torques on Co for the optimal Pt thickness. Our findings not only demonstrate the crucial role that orbital currents can play in low-dimensional systems with weak spin–orbit coupling but also reveal that they enable more energy efficient manipulation of magnetization in spintronic devices. [ABSTRACT FROM AUTHOR]

The composition of the marine phytoplankton community has been shown to impact many biogeochemical processes and marine ecosystem services. A variety of methods exist to characterize phytoplankton community composition (PCC), with varying degrees of taxonomic resolution. Accordingly, the resulting PCC determinations are dependent on the method used. Here, we use surface ocean samples collected in the North Atlantic and North Pacific Oceans to compare high‐performance liquid chromatography pigment‐based PCC to four other methods: quantitative cell imaging, flow cytometry, and 16S and 18S rRNA amplicon sequencing. These methods allow characterization of both prokaryotic and eukaryotic PCC across a wide range of size classes. PCC estimates of many taxa resolved at the class level (e.g., diatoms) show strong positive correlations across methods, while other groups (e.g., dinoflagellates) are not well captured by one or more methods. Since variations in phytoplankton pigment concentrations are related to changes in optical properties, this combined dataset expands the potential scope of ocean color remote sensing by associating PCC at the genus‐ and species‐level with group‐ or class‐level PCC from pigments. Quantifying the strengths and limitations of pigment‐based PCC methods compared to PCC assessments from amplicon sequencing, imaging, and cytometry methods is the first step toward the robust validation of remote sensing approaches to quantify PCC from space. [ABSTRACT FROM AUTHOR]

InGaN/GaN single quantum wells were grown by molecular beam epitaxy on the silicon substrate onto thin AlN and GaN buffer layers. The InGaN/GaN structure is porosified using a combination of SixNy nanomasking and sublimation and compared with a non-porous reference. The photoluminescence efficiency at room temperature of the porosified sample is improved by a factor reaching 40 compared with the reference sample. Plan-view and cross-sectional transmission electron microscopy images reveal that the remaining material is free of dislocation cores. The regions around dislocations are, thus, preferentially sublimated. This explains the strong photoluminescence improvement of nanoporous InGaN/GaN samples. [ABSTRACT FROM AUTHOR]

Gold nanoparticles have been used as drug carriers and imaging reagents. The plant extract-capped gold nanoparticles provide better properties than chemically synthesized gold nanoparticles. In this study, Zingiber zerumbet extract-mediated green production of gold nanoparticles (Z. zerumbet@Au NPs) was established. Based on the UV-visible spectroscopy and transmission electron microscope (TEM) results, most Z. zerumbet@Au NPs were spherical. When more Z. zerumbet extracts were added, more spherical nanoparticles were formed. The hydrodynamic size changed slightly along with time, and the average size was approximately 170 nm. Capping of Z. zerumbet extract on the surface of gold nanoparticles was confirmed by Fourier transform infrared spectroscopy (FTIR). In general, phenolic compounds or flavonoid compounds were considered to be the reducing agent. However, zerumbone was identified as the reducing agent in this study. The resulting oxidized products were characterized by high-performance liquid chromatography-mass spectrometry (HPLC-MS). As a result, the solvent was proven to be involved in nanoparticle synthesis. Overall, Z zerumbet@Au NPs showed great potential to be used in cosmetic- or biomedicine-related fields. [ABSTRACT FROM AUTHOR]

Introduction. Dual-mobility (DM) implants for total hip arthroplasty (THA) have gained popularity due to their potential to reduce hip instability and dislocation events that may lead to revision surgery. These implants consist of a femoral head articulated within a polyethylene liner, which articulates within an outer acetabular shell, creating a dual-bearing surface. Our study aimed to report our observations on the survivorship of a novel DM implant for primary total hip arthroplasty at two years. Methods. We conducted a retrospective, multicenter study to assess the clinical outcomes of patients undergoing a THA with a novel DM implant (OR3O acetabular system™, Smith & Nephew, Inc., Memphis, TN) from January 2020 to September 2021. Patient demographics, surgical information, and survivorship data were collected from medical records for patients with a minimum of two years of follow-up. Primary outcomes included overall implant survivorship at two years as well as aseptic survivorship, revision rates of the DM acetabular shell, and average time to revision. Patient-reported outcomes were collected in the form of HOOS JR. Results. A total of 250 hips in 245 patients had a minimum two-year follow-up. Primary osteoarthritis (80%) was the most common indication for index THA. The average aseptic survivorship of the DM acetabular components at two years for the cohort was 98.4% and survivorship of the acetabular implants overall was 97.6%. There were a total of four (1.6%) aseptic revisions of the DM acetabular component. Reasons for aseptic acetabular revision included one case of instability, one intraprosthetic dislocation, one periprosthetic acetabular fracture, and one malpositioned acetabular cup resulting in impingement. The mean time of follow-up was 893.9 days. Eighty-seven patients had preoperative and two-year HOOS JR available. HOOS JR improved by an average of 38.5 points. Conclusion. This novel DM acetabular implant demonstrates excellent survivorship at two years follow-up with low rates of instability and intraprosthetic dislocation and no episodes of metal-on-metal corrosion. Use of the DM implant demonstrated clinically relevant improvements in patient-reported outcomes at two years. [ABSTRACT FROM AUTHOR]

Background The ongoing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic posed an unpreceded threat to the management of other pandemics such as human immunodeficiency virus-1 (HIV-1) in the United States. The full impact of the SARS-CoV-2 pandemic on the HIV-1 pandemic needs to be evaluated. Methods All individuals with newly reported HIV-1 diagnoses from NC State Laboratory of Public Health were enrolled in this prospective observational study, 2018–2021. We used a sequencing-based recency assay to identify recent HIV-1 infections and to determine the days postinfection (DPI) for each person at the time of diagnosis. Results Sequencing used diagnostic serum samples from 814 individuals with new HIV-1 diagnoses spanning this 4-year period. Characteristics of individuals diagnosed in 2020 differed from those in other years. People of color diagnosed in 2021 were on average 6 months delayed in their diagnosis compared to those diagnosed in 2020. There was a trend that genetic networks were more known for individuals diagnosed in 2021. We observed no major integrase resistance mutations over the course of the study. Conclusions SARS-CoV-2 pandemic may contribute to the spread of HIV-1. Public health resources need to focus on restoring HIV-1 testing and interrupting active, ongoing, transmission. [ABSTRACT FROM AUTHOR]

In this article we quantitatively and qualitatively analyze a sample of novice programmer compilation log data, exploring whether (or how) low-achieving, average, and high-achieving students vary in their grasp of these introductory concepts. High-achieving students self-reported having the easiest time learning the introductory programming topics. In a quantitative analysis, though, high-achieving and average students were: 1) more effective at debugging (on average, as quantified by Jadud's Error Quotient (EQ)) than low-achieving students; and 2) were least confused, as quantified using Lee's confusion metric. However, the differences in EQ and confusion between groups were not statistically significant. This implied that all groups struggled with programming to similar extents. This finding was further supported by was used to delineate two sets of variables. The results indicate that preference for autonomy in computer science learning positively predicts self-efficacy in learning computer science with the strongest coefficient. Computer science learner preference for teacher control is also a positive predictor. However, preference for participation in managing the computer class and preference for depending on the teacher did not play a significant role in the students' self-efficacy in learning computer science.