Proton-nucleus (p+A) collisions have long been recognized as a crucial component of the physics program with nuclear beams at high energies, in particular for their reference role to interpret and ...understand nucleus-nucleus data as well as for their potential to elucidate the partonic structure of matter at low parton fractional momenta (small-x). Here, we summarize the main motivations that make a proton-nucleus run a decisive ingredient for a successful heavy-ion program at the Large Hadron Collider (LHC) and we present unique scientific opportunities arising from these collisions. We also review the status of ongoing discussions about operation plans for the p+A mode at the LHC.
Multiwalled carbon nanotube-supported Pt (Pt/MWNT) nanocomposites were prepared by both the aqueous solution reduction of a Pt salt (HCHO reduction) and the reduction of a Pt ion salt in ethylene ...glycol solution. For comparison, a Pt/XC-72 nanocomposite was also prepared by the EG method. The Pt/MWNT catalyst prepared by the EG method has a high and homogeneous dispersion of spherical Pt metal particles with a narrow particle-size distribution. TEM images show that the Pt particle size is in the range of 2−5 nm with a peak at 2.6 nm, which is consistent with 2.5 nm obtained from the XRD broadening calculation. Surface chemical modifications of MWNTs and water content in EG solvent are found to be the key factors in depositing Pt particles on MWNTs. In the case of the direct methanol fuel cell (DMFC) test, the Pt/MWNT catalyst prepared by EG reduction is slightly superior to the catalyst prepared by aqueous reduction and displays significantly higher performance than the Pt/XC-72 catalyst. These differences in catalytic performance between the MWNT-supported or the carbon black XC-72-supported catalysts are attributed to a greater dispersion of the supported Pt particles when the EG method is used, in contrast to aqueous HCHO reduction and to possible unique structural and higher electrical properties when contrasting MWNTs to carbon black XC-72 as a support.
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IJS, KILJ, NUK, PNG, UL, UM
Heparin‐binding epidermal growth factor (HB‐EGF) and betacellulin (BTC) are activating ligands for EGF receptor (EGFR/ErbB1) and ErbB4. To identify their physiological functions, we disrupted mouse ...HB‐EGF and BTC alleles by homologous recombination. Most HB‐EGF−/− mice died before weaning, and survivors had enlarged, dysfunctional hearts and reduced lifespans. Although BTC−/− mice were viable and fertile and displayed no overt defects, the lifespan of double null HB‐EGF−/−/BTC−/− mice was further reduced, apparently due to accelerated heart failure. HB‐EGF−/− newborns had enlarged and malformed semilunar and atrioventricular heart valves, and hypoplastic, poorly differentiated lungs. Defective cardiac valvulogenesis was the result of abnormal mesenchymal cell proliferation during remodeling, and was associated with dramatic increases in activated Smad1/5/8. Consistent with the phenotype, HB‐EGF transcripts were localized to endocardial cells lining the margins of wild‐type valves. Similarly defective valvulogenesis was observed in newborn mice lacking EGFR and tumor necrosis factor‐α converting enzyme (TACE). These results suggest that cardiac valvulogenesis is dependent on EGFR activation by TACE‐derived soluble HB‐EGF, and that EGFR signaling is required to regulate bone morphogenetic protein signaling in this context.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
•In comparison to the graphene/Ag hybrid system, the MoS2/Ag hybrid system can grow in low temperature that can maintain the morphology of AgNPs.•Compared with the Ag system for surface-enhanced ...Raman spectroscopy, the MoS2/Ag hybrid system has a better enhancement effect, which is attributed to the EM enhancement effect from AgNPs and CM enhancement effect from MoS2.•The MoS2/AgNPs hybrid system shows high performance in terms of sensitivity, signal-to-noise ratio, reproducibility and stability.
Few layers MoS2 were directly synthesized on Ag nanoparticles (AgNPs) by thermal decomposion method to fabricate a MoS2/AgNPs hybrid system for surface-enhanced Raman scattering (SERS). The MoS2/AgNPs hybrid system shows high performance in terms of sensitivity, signal-to-noise ratio, reproducibility and stability. The minimum detected concentration from MoS2/AgNPs hybrid system for R6G can reach 10−9M, which is one order of magnitude lower than that from AgNPs system. The hybrid system shows the reasonable linear response between the Raman intensity and concentration that R2 is reached to 0.988. The maximum deviations of SERS intensities from 20 positions of the SERS substrate are less than 13%. Besides, the hybrid system has a good stability, the Raman intensity only drop by 20% in a month. This work can provide a basis for the fabrication of novel SERS substrates.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
485.
Angiosperm phylogeny: 17 genes, 640 taxa Soltis, Douglas E.; Smith, Stephen A.; Cellinese, Nico ...
American journal of botany,
April 2011, Volume:
98, Issue:
4
Journal Article
Peer reviewed
Open access
Premise of the study. Recent analyses employing up to five genes have provided numerous insights into angiosperm phylogeny, but many relationships have remained unresolved or poorly supported. In the ...hope of improving our understanding of angiosperm phylogeny, we expanded sampling of taxa and genes beyond previous analyses. Methods: We conducted two primary analyses based on 640 species representing 330 families. The first included 25260 aligned base pairs (bp) from 17 genes (representing all three plant genomes, i. e., nucleus, plastid, and mitochondrion). The second included 19846 aligned bp from 13 genes (representing only the nucleus and plastid). Key results: Many important questions of deep-level relationships in the nonmonocot angiosperms have now been resolved with strong support. Amborellaceae, Nymphaeales, and Austrobaileyales are successive sisters to the remaining angiosperms (Mesangiospermae), which are resolved into Chloranthales + Magnoliidae as sister to Monocotyledoneae + Ceratophyllaceae + Eudicotyledoneae. Eudicotyledoneae contains a basal grade subtending Gunneridae. Within Gunneridae, Gunnerales are sister to the remainder (Pentapetalae), which comprises (1) Superrosidae, consisting of Rosidae (including Vitaceae) and Saxifragales; and (2) Superasteridae, comprising Berberidopsidales, Santalales, CaryophyHales, Asteridae, and, based on this study, Dilleniaceae (although other recent analyses disagree with this placement). Within the major subclades of Pentapetalae, most deep-level relationships are resolved with strong support. Conclusions: Our analyses confirm that with large amounts of sequence data, most deep-level relationships within the angiosperms can be resolved. We anticipate that this well-resolved angiosperm tree will be of broad utility for many areas of biology, including physiology, ecology, paleobiology, and genomics.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NMLJ, NUK, OILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
A nanostructured Ni60-TiB2 composite coating was sprayed onto a steel substrate by a high velocity oxy-fuel (HVOF) process using high energy ball milled powders. Its sliding wear resistance at ...room-temperature was evaluated by ball-on-disc testing. For comparison, a conventional Ni60-TiB2 composite coating was prepared by HVOF using mechanically mixed Ni60 and TiB2 powders and tested under the same conditions. The results showed that the nanostructured composite coating had excellent mechanical properties and sliding wear resistance due to the microstructural homogenisation and the well preserved nanostructured characteristics of the ball milled powders. Adhesive and abrasive wear were responsible for the wear down mechanisms of the nanostructured Ni60-TiB2 composite coating.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
IMPORTANCE: The optimal systolic blood pressure (SBP) to minimize the risk of dementia in older age is unknown. OBJECTIVE: To investigate whether the association between SBP and dementia risk is ...U-shaped and whether age and comorbidity play a role in this association. DESIGN, SETTING, AND PARTICIPANTS: This cohort study used an individual participant data approach to analyze 7 prospective, observational, population-based cohort studies that were designed to evaluate incident dementia in older adults. These studies started between 1987 and 2006 in Europe and the US. Participants had no dementia diagnosis and had SBP and/or diastolic blood pressure (BP) data at baseline and incident dementia status during follow-up. Data analysis was conducted from November 7, 2019, to October 3, 2021. EXPOSURES: Baseline systolic BP. MAIN OUTCOMES AND MEASURES: All-cause dementia (defined using Diagnostic and Statistical Manual of Mental Disorders Third Edition Revised or Diagnostic and Statistical Manual of Mental Disorders Fourth Edition and established at follow-up measurements or in clinical practice), mortality, and combined dementia and mortality were the outcomes. Covariates included baseline antihypertensive medication use, sex, educational level, body mass index, smoking status, diabetes, stroke history, myocardial infarction history, and polypharmacy. Cox proportional hazards regression models were used, and nonlinear associations were explored using natural splines. RESULTS: The study analyzed 7 cohort studies with a total of 17 286 participants, among whom 10 393 were women (60.1%) and the mean (SD) baseline age was 74.5 (7.3) years. Overall, dementia risk was lower for individuals with higher SBP, with the lowest risk associated with an SBP of approximately 185 mm Hg (95% CI, 161-230 mm Hg; P = .001). Stratified by overlapping 10-year baseline age groups, the lowest dementia risk was observed at somewhat lower systolic BP levels in those older than 75 years (158 95% CI, 152-178 mm Hg to 170 95% CI, 160-260 mm Hg). For mortality, there was a clear U-shaped association, with the lowest risk at 160 mm Hg (95% CI, 154-181 mm Hg; P < .001). This U-shape occurred across all age groups, with the lowest dementia risk associated with an SBP of 134 mm Hg (95% CI, 102-149 mm Hg; P = .03) in those aged 60 to 70 years and increasing to between 155 mm Hg (95% CI, 150-166 mm Hg; P < .001) and 166 mm Hg (95% CI, 154-260 mm Hg; P = .02) for age groups between 70 and 95 years. Combined dementia and mortality risk curves closely resembled those for mortality. Associations of diastolic BP with dementia risk were generally similar but were less distinct. CONCLUSIONS AND RELEVANCE: This cohort study found that dementia risk was lower for older individuals with higher SBP levels and that more distinctly U-shaped associations appeared for those older than 75 years, but these associations cannot be explained by SBP-associated changes in mortality risk. The findings may warrant future trials on tailored BP management in older age groups that take life expectancy and health context into consideration.
Short Range Correlations (SRCs) have been identiffed as being responsible for the high momentum tail of the nucleon momentum distribution, n(k). Hard, short-range interactions of nucleon pairs ...generate the high momentum tail and imprint a universal character on n(k) for all nuclei at large momentum. Triple coincidence experiments have shown a strong dominance of np pairs, but these measurements involve large final state interactions. This paper presents the results from Jefferson Lab experiment E08014 which measured inclusive electron scattering cross-section from Ca isotopes. Here, by comparing the inclusive cross section from 48Ca to 40Ca in a kinematic region dominated by SRCs we provide a new way to study the isospin structure of SRCs.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
We present that the next-generation Enriched Xenon Observatory (nEXO) is a proposed experiment to search for neutrinoless double- β (0νββ) decay in 136Xe with a target half-life sensitivity of ...approximately 1028 yr using 5 × 103 kg of isotopically enriched liquid-xenon in a time projection chamber. This improvement of two orders of magnitude in sensitivity over current limits is obtained by a significant increase of the 136Xe mass, the monolithic and homogeneous configuration of the active medium, and the multiparameter measurements of the interactions enabled by the time projection chamber. Finally, the detector concept and anticipated performance are presented based upon demonstrated realizable background rates.
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A simple, point of care, inexpensive, disposable cassette for the detection of nucleic acids extracted from pathogens was designed, constructed, and tested. The cassette utilizes a single reaction ...chamber for isothermal amplification of nucleic acids. The chamber is equipped with an integrated, flow-through, Flinders Technology Associates (Whatman FTA®) membrane for the isolation, concentration, and purification of DNA and/or RNA. The nucleic acids captured by the membrane are used directly as templates for amplification without elution, thus simplifying the cassette's flow control. The FTA membrane also serves another critical role-enabling the removal of inhibitors that dramatically reduce detection sensitivity. Thermal control is provided with a thin film heater external to the cassette. The amplification process was monitored in real time with a portable, compact fluorescent reader. The utility of the integrated, single-chamber cassette was demonstrated by detecting the presence of HIV-1 in oral fluids. The HIV RNA was reverse transcribed and subjected to loop-mediated, isothermal amplification (LAMP). A detection limit of less than 10 HIV particles was demonstrated. The cassette is particularly suitable for resource poor regions, where funds and trained personnel are in short supply. The cassette can be readily modified to detect nucleic acids associated with other pathogens borne in saliva, urine, and other body fluids as well as in water and food.