Direct writing of single germanium vacancy center arrays in diamond

© 2018 The Author(s). Color centers in diamond are promising solid-state qubits for scalable quantum photonics applications. Amongst many defects, those with inversion symmetry are of an interest due to their promising optical properties. In this work, we demonstrate a maskless implantation of an array of bright, single germanium vacancy (GeV) centers in diamond. Employing the direct focused ion beam technique, single GeV emitters are engineered with the spatial accuracy of tens of nanometers. The single GeV creation ratio reaches as high as 53% with the dose of 200 Ge + ions per spot. The presented fabrication method is promising for future nanofabrication of integrated photonic structures with GeV emitters as a leading platform for spin-spin interactions

Optical Gating of Resonance Fluorescence from a Single Germanium Vacancy Color Center in Diamond

© 2019 American Physical Society. Scalable quantum photonic networks require coherent excitation of quantum emitters. However, many solid-state systems can undergo a transition to a dark shelving state that inhibits the resonance fluorescence. Here, we demonstrate that by a controlled gating using a weak nonresonant laser, the resonant fluorescence can be recovered and amplified for single germanium vacancies. Employing the gated resonance excitation, we achieve optically stable resonance fluorescence of germanium vacancy centers. Our results are pivotal for the deployment of diamond color centers as reliable building blocks for scalable solid-state quantum networks

Estimating genomic instability mediated by Alu retroelements in breast cancer

Alu-PCR is a relatively simple technique that can be used to investigate genomic instability in cancer. This technique allows identification of the loss, gain or amplification of gene sequences based on the analysis of segments between two Alu elements coupled with quantitative and qualitative analyses of the profiles obtained from tumor samples, surgical margins and blood. In this work, we used Alu-PCR to identify gene alterations in ten patients with invasive ductal breast cancer. Several deletions and insertions were identified, indicating genomic instability in the tumor and adjacent normal tissue. Although not associated with specific genes, the alterations, which involved chromosomal bands 1p36.23, 1q41, 11q14.3, 13q14.2, occurred in areas of well-known genomic instability in breast and other types of cancer. These results indicate the potential usefulness of Alu-PCR in identifying altered gene sequences in breast cancer. However, caution is required in its application since the Alu primer can produce non-specific amplification

Genetic polymorphism of the serine rich antigen N-terminal region in Plasmodium falciparum field isolates from Brazil

In this work we investigated the frequency of polymorphism in exon II of the gene encoding most of the amino-terminal region of the serine rich antigen (SERA) in Plasmodium falciparum field samples. The blood samples were colleted from P. falciparum infected individuals in three areas of the Brazilian Amazon. Two fragments have been characterized by polymerase chain reaction: one of 175 bp corresponding to the repeat region with 5 octamer units and one other of 199 bp related to the 6 repeat octamer units of SERA protein. The 199 bp fragment was the predominant one in all the studied areas. The higher frequency of this fragment has not been described before and could be explained by an immunological selection of the plasmodial population in the infected individuals under study. Since repeat motifs in the amino-terminal region of SERA contain epitopes recognized by parasite-inhibitor antibodies, data reported here suggest that the analysis of the polymorphism of P. falciparum isolates in different geographical areas is a preliminary stage before the final drawing of an universal vaccine against malaria can be reached

Relationships between TGFβ Proteins and Oxygen Concentrations Inside the First Trimester Human Gestational Sac

In early pregnancy, the O2 gradient between the maternal circulation and the gestational sac tissues modulates trophoblast biological functions. The aim was to evaluate if placental partial pressure of oxygen (PaO2) modulates in vivo synthesis of specific placental proteins inside the first trimester gestational sac. Matched samples of peripheral venous blood, blood from the placental bed (PB), coelomic fluid (CF) and placental tissue were obtained in 37 normal pregnancies at 6–12 weeks gestation. PaO2 was measured in PB and CF using an IRMA blood gas monitor. Inhibin A, activin A, sEng, PlGF, sFlt-1 and free VEGF concentrations were measured in all samples. HSP 70 was measured in placental extracts. ANOVA showed ∼60% increase in PB PaO2 (P = 0.02) between after 10 weeks gestation. Unpaired Student's T-test between two groups (6–9 weeks vs 9–12 weeks) shows a significant increase in MS Activin A (P = 0.001), CF activin A (P<0.001), MS P1GF (P = 0.001), CF PlGF (P<0.001), MS sFLT-1 (P = 0.03), CF sFLT-1 (P = 0.01), HSP 70 in placental extracts (P = 0.04) and a significant decrease in PB inhibin A levels (P<0.001) and PB sFLT-1 (P = 0.02) . Multiple correlation analysis showed a significant negative correlation between PB inhibin A levels and gestation (r = −0.45, P<0.05) and PB PaO2 (r = −0.5, P = 0.008) and also between sFLT-1 and PB PaO2 (P = 0.03). There was a positive correlation (P<0.01) between PlGF, sEng and VEGF levels in the placental extracts. Our results indicate a direct relationship in the early intrauterine PaO2 in vivo and inhibin A and sFLT-1 concentrations confirming our hypothesis that specific placental proteins are regulated by intrauterine O2 tension

Forty years literature review of primary lung lymphoma

There are several unresolved issues through out the literature regarding the entity of primary lung lymphoma. Extensive literature review of this uncommon pathology is carried out

Echinococcus multilocularis and Echinococcus shiquicus in a small mammal community on the eastern Tibetan Plateau : host species composition, molecular prevalence, and epidemiological implications

Background The eastern part of the Tibetan Plateau is now recognized as an endemic region with the highest reported human infection rates in the world of human alveolar echinococcosis (AE) caused by Echinococcus multilocularis. Existing epidemiological studies on AE have mainly focused on the synanthropic environment, while basic parasitological and ecological aspects in wildlife host species remain largely unknown, especially for small mammal hosts. Therefore, we examined small mammal host species composition, occurrence, and the prevalence of both E. multilocularis and E. shiquicus in Shiqu County (Sichuan Province, China), eastern Tibetan Plateau. Results In total, 346 small mammals from five rodent and one pika species were trapped from four randomly set 0.25 ha square plots. Two vole species, Lasiopodomys fuscus (n = 144) and Microtus limnophilus (n = 44), and the plateau pika (Ochotona curzoniae) (n = 135), were the three most-dominant species trapped. Although protoscoleces of E. multilocularis and E. shiquicus were only observed in L. fuscus and O. curzoniae, respectively, cox1 and nad1 gene DNA of E. shiquicus was detected in all the small mammal species except for Neodon irene, whereas E. multilocularis was detected in the three most-dominant species. The overall molecular prevalence of Echinococcus species was 5.8 (95% CI: 3.3–8.2%) ~ 10.7% (95% CI: 7.4–14.0%) (the conservative prevalence to the maximum prevalence with 95% CI in parentheses), whereas for E. multilocularis it was 4.3 (95% CI: 2.2–6.5%) ~ 6.7% (95% CI: 4.0–9.3%), and 1.5 (95% CI: 0.2–2.7%) ~ 4.1% (95% CI: 2.0–6.1%) for E. shiquicus. The prevalence of both E. multilocularis and E. shiquicus, was significantly higher in rodents (mainly voles) than in pikas. Phylogenetic analyses revealed that Echinococcus haplotypes of cox1 from small mammal hosts were actively involved in the sylvatic and anthropogenic transmission cycles of E. multilocularis in the eastern Tibetan Plateau. Conclusions In contrast to previous studies, the current results indicated that rodent species, rather than pikas, are probably more important natural intermediate hosts of E. multilocularis and E. shiquicus in the eastern Tibetan Plateau. Thus, understanding interspecific dynamics between rodents and pikas is essential to studies of the echinococcosis transmission mechanism and human echinococcosis prevention in local communities. Keywords: Echinococcus multilocularis, E. shiquicus, Small mammal Prevalence, Tibetan Platea

Anthropogenic contributions to global carbonyl sulfide, carbon disulfide and organosulfides fluxes

Previous studies of the global sulfur cycle have focused almost exclusively on oxidized species and just a few sulfides. This focus is expanded here to include a wider range of reduced sulfur compounds. Inorganic sulfides tend to be bound into sediments, and sulfates are present both in sediments and the oceans. Sulfur can adopt polymeric forms that include S-S bonds. This review examines the global anthropogenic sources of reduced sulfur, updating emission inventories and widening the consideration of industrial sources. It estimates the anthropogenic fluxes of key sulfides to the atmosphere (units Gg S a-1) as: carbonyl sulfide (total 591: mainly from pulp and pigment 171, atmospheric oxidation of carbon disulfide 162, biofuel and coal combustion, 133, natural 898 Gg S a-1), carbon disulfide (total 746: rayon 395, pigment 205, pulp 78, natural 330 Gg S a-1), methanethiol (total 2119: pulp 1680, manure 330, rayon and wastewater 102, natural 6473 Gg S a-1), dimethyl sulfide (total 2197: pulp 1462, manure 660 and rayon 36, natural 31 657 Gg S a-1), dimethyl disulfide (total 1103: manure 660, pulp 273; natural 1081 Gg S a-1). The study compares the magnitude of the natural sources: marine, vegetation and soils, volcanoes and rain water with the key anthropogenic sources: paper industry, rayon-cellulose manufacture, agriculture and pigment production. Industrial sources could be reduced by better pollution control, so their impact may lessen over time. Anthropogenic emissions dominate the global budget of carbon disulfide, and some aromatic compounds such as thiophene, with emissions of methanethiol and dimethyl disufide also relatively important. Furthermore, industries related to coal and bitumen are key sources of multi-ringed thiophenes, while food production and various wastes may account for the release of significant amounts of dimethyl disulfide and dimethyl trisulfide