Origin of slow magnetic relaxation in Kramers ions with non-uniaxial anisotropy

Transition metal ions with long-lived spin states represent minimum size magnetic bits. Magnetic memory has often been associated with the combination of high spin and strong uniaxial magnetic anisotropy. Yet, slow magnetic relaxation has also been observed in some Kramers ions with dominant easy-plane magnetic anisotropy, albeit only under an external magnetic field. Here we study the spin dynamics of cobalt(II) ions in a model molecular complex. We show, by means of quantitative first-principles calculations, that the slow relaxation in this and other similar systems is a general consequence of time-reversal symmetry that hinders direct spin–phonon processes regardless of the sign of the magnetic anisotropy. Its magnetic field dependence is a subtle manifestation of electronuclear spin entanglement, which opens relaxation channels that would otherwise be forbidden but, at the same time, masks the relaxation phenomenon at zero field. These results provide a promising strategy to synthesize atom-size magnetic memories

Estado fitosanitario del azafrán en Aragón (España): Insectos, ácaros, nematodos, virus, bacterias y malas hierbas

El azafrán cultivado en España está adquiriendo relevancia en las últimas décadas como producto de gran calidad, lo que requiere la selección de cormos, sus órganos reproductivos, sanos para la plantación con el objetivo de mantener un adecuado estado fitosanitario del cultivo. Este trabajo presenta un estudio del estado fitosanitario del azafrán en Teruel, donde el cultivo fue muy importante económica y socialmente. Además, este estudio pretende ser de utilidad para las zonas productoras con características agroclimáticas similares. Con dichos objetivos, se prospectaron 10 plantaciones comerciales de azafrán en 6 localidades del valle del Jiloca entre los años 2008 y 2011, estudiando la presencia de insectos, ácaros, nematodos, virus, bacterias y malas hierbas. El ácaro Rhizoglyphus robini, una de las plagas más importantes del azafrán, se detectó en los cormos y en el suelo en una parcela. También el nematodo Aphelenchoides blastophtorus, plaga en plantas ornamentales, se encontró abundantemente en cormos de dos parcelas. Se detectaron infecciones ocasionales de virus del género potyvirus en el cultivo y en la mala hierba Eruca vesicaria. Las malas hierbas Lolium rigidum y Descurainia sophia podrían causar serios problemas de competencia al cultivo y se considera necesario realizar operaciones de escarda en otoño y en invierno. No se detectaron insectos nocivos ni bacterias fitopatógenas. La multiplicación vegetativa del azafrán hace aconsejable realizar muestreos, especialmente en los cormos antes de ser replantados, para detectar la presencia de ácaros, nematodos y virus que podrían ocasionar pérdidas de producción y calidad. In the last decades, saffron produced in Spain is gaining relevance as a high-quality product, which requires the selection of healthy corms (the reproductive organ) for planting in order to maintain adequa-te phytosanitary status of the crop. In this work, the phytosanitary status of saffron was studied in Teruel (Aragón, Spain), where the crop has economic and social importance. Moreover, it aims to be useful for the production areas with similar agro-climatic characteristics. Ten commercial saffron plantations in six locations of the Jiloca valley have been surveyed between 2008 and 2011 and the presence of insects, mites, nematodes, virus, bacteria and weeds was studied. The mite Rhizoglyphus robini, one of the most important pests of saffron, was detected in both corms and soil in one plantation. The nematode Aphelenchoides blastophtorus, pest in ornamental plants, was also found in corms in two plantations. Potyvirus infections were occasionally detected in both the crop and in the weed Eruca vesicaria. The weeds Lolium rigidum and Descurainia sophia could cause diminutions of the yield by competition, therefore, weeding operations are necessary in autumn and winter. No harmful insects and phytopatogenic bacteria were detected. Because reproduction is only possible through corm propagation, it is advisable to analyse the plants, especially the corms, before being re-planted, in order to detect the presence of mites, nematodes and virus that could reduce yield and quality decreases

The cellular origin and malignant transformation of Waldenström macroglobulinemia

Although information about the molecular pathogenesis of Waldenström macroglobulinemia (WM) has significantly advanced, the precise cell of origin and the mechanisms behind WM transformation from immunoglobulin-M (IgM) monoclonal gammopathy of undetermined significance (MGUS) remain undetermined. Here, we undertook an integrative phenotypic, molecular, and genomic approach to study clonal B cells from newly diagnosed patients with IgM MGUS (n = 22), smoldering (n = 16), and symptomatic WM (n = 11). Through principal component analysis of multidimensional flow cytometry data, we demonstrated highly overlapping phenotypic profiles for clonal B cells from IgM MGUS, smoldering, and symptomatic WM patients. Similarly, virtually no genes were significantly deregulated between fluorescence-activated cell sorter-sorted clonal B cells from the 3 disease groups. Interestingly, the transcriptome of the Waldenström B-cell clone was highly different than that of normal CD25-CD22+ B cells, whereas significantly less genes were differentially expressed and specific WM pathways normalized once the transcriptome of the Waldenström B-cell clone was compared with its normal phenotypic (CD25+CD22+low) B-cell counterpart. The frequency of specific copy number abnormalities [+4, del(6q23.3-6q25.3), +12, and +18q11-18q23] progressively increased from IgM MGUS and smoldering WM vs symptomatic WM (18% vs 20% and 73%, respectively; P = .008), suggesting a multistep transformation of clonal B cells that, albeit benign (ie, IgM MGUS and smoldering WM), already harbor the phenotypic and molecular signatures of the malignant Waldenström clone.This study was supported by Cooperative Research Thematic Network grants RD12/0036/0058 and RD12/0036/0048 of the Red de Cancer (Cancer Network of Excellence), Consejería de Sanidad, Junta de Castilla y Leon, Valladolid, Spain (557/A/10).Peer Reviewe

De-escalation studies in HPV-positive oropharyngeal cancer:How should we proceed?

Human papilloma virus (HPV) is a well-established causative factor in a subset of squamous cell carcinomas of the head and neck (HNSCC). Although HPV can be detected in various anatomical subsites, HPV-positive oropharyngeal squamous cell carcinoma (OPSCC) is the most common HPV-related malignancy of the head and neck, and its worldwide incidence is constantly rising. Patients with OPSCC are generally younger, have less co-morbidities and generally have better prognosis due to different biological mechanisms of carcinogenesis. These facts have generated hypotheses on potential treatment modifications, aiming to minimize treatment-related toxicities without compromising therapy efficacy. Numerous randomized clinical trials have been designed to verify this strategy and increasingly real-world evidence data from retrospective, observational studies is becoming available. Until now, the data do not support any modification in contemporary treatment protocols. In this narrative review, we outline recent data provided by both randomized controlled trials and real-world evidence of HPV-positive OPSCC in terms of clinical value. We critically analyze the potential value and drawbacks of the available data and highlight future research directions. This article was written by members and invitees of the International Head and Neck Scientific Group. (www.IHNSG.com)</p

Measurement of the Lifetime Difference Between B_s Mass Eigenstates

We present measurements of the lifetimes and polarization amplitudes for B_s --> J/psi phi and B_d --> J/psi K*0 decays. Lifetimes of the heavy (H) and light (L) mass eigenstates in the B_s system are separately measured for the first time by determining the relative contributions of amplitudes with definite CP as a function of the decay time. Using 203 +/- 15 B_s decays, we obtain tau_L = (1.05 +{0.16}/-{0.13} +/- 0.02) ps and tau_H = (2.07 +{0.58}/-{0.46} +/- 0.03) ps. Expressed in terms of the difference DeltaGamma_s and average Gamma_s, of the decay rates of the two eigenstates, the results are DeltaGamma_s/Gamma_s = (65 +{25}/-{33} +/- 1)%, and DeltaGamma_s = (0.47 +{0.19}/-{0.24} +/- 0.01) inverse ps.Comment: 8 pages, 3 figures, 2 tables; as published in Physical Review Letters on 16 March 2005; revisions are for length and typesetting only, no changes in results or conclusion

Flow cytometry for fast screening and automated risk assessment in systemic light-chain amyloidosis

Early diagnosis and risk stratification are key to improve outcomes in light-chain (AL) amyloidosis. Here we used multidimensional-flow-cytometry (MFC) to characterize bone marrow (BM) plasma cells (PCs) from a series of 166 patients including newly-diagnosed AL amyloidosis (N = 94), MGUS (N = 20) and multiple myeloma (MM, N = 52) vs. healthy adults (N = 30). MFC detected clonality in virtually all AL amyloidosis (99%) patients. Furthermore, we developed an automated risk-stratification system based on BMPCs features, with independent prognostic impact on progression-free and overall survival of AL amyloidosis patients (hazard ratio: ≥ 2.9;P ≤ .03). Simultaneous assessment of the clonal PCs immunophenotypic protein expression profile and the BM cellular composition, mapped AL amyloidosis in the crossroad between MGUS and MM; however, lack of homogenously-positive CD56 expression, reduction of B-cell precursors and a predominantly-clonal PC compartment in the absence of an MM-like tumor PC expansion, emerged as hallmarks of AL amyloidosis (ROC-AUC = 0.74;P < .001), and might potentially be used as biomarkers for the identification of MGUS and MM patients, who are candidates for monitoring pre-symptomatic organ damage related to AL amyloidosis. Altogether, this study addressed the need for consensus on how to use flow cytometry in AL amyloidosis, and proposes a standardized MFC-based automated risk classification ready for implementation in clinical practice

Immunogenetic characterization of clonal plasma cells in systemic light-chain amyloidosis

This study was supported by the Centro de Investigación Biomédica en Red—Área de Oncología—del Instituto de Salud Carlos III (CIBERONC; CB16/12/00369; and CB16/12/00489), Instituto de Salud Carlos III/Subdirección General de Investigación Sanitaria (FIS No. PI13/02196), Asociación Española Contra el Cáncer (GCB120981SAN and the Accelerator Award), CRIS against Cancer foundation grant 2014/0120, and the Black Swan Research Initiative of the International Myeloma Foundation.Peer reviewe