41 research outputs found
Measurement of the Bottom-Strange Meson Mixing Phase in the Full CDF Data Set
We report a measurement of the bottom-strange meson mixing phase \beta_s
using the time evolution of B0_s -> J/\psi (->\mu+\mu-) \phi (-> K+ K-) decays
in which the quark-flavor content of the bottom-strange meson is identified at
production. This measurement uses the full data set of proton-antiproton
collisions at sqrt(s)= 1.96 TeV collected by the Collider Detector experiment
at the Fermilab Tevatron, corresponding to 9.6 fb-1 of integrated luminosity.
We report confidence regions in the two-dimensional space of \beta_s and the
B0_s decay-width difference \Delta\Gamma_s, and measure \beta_s in [-\pi/2,
-1.51] U [-0.06, 0.30] U [1.26, \pi/2] at the 68% confidence level, in
agreement with the standard model expectation. Assuming the standard model
value of \beta_s, we also determine \Delta\Gamma_s = 0.068 +- 0.026 (stat) +-
0.009 (syst) ps-1 and the mean B0_s lifetime, \tau_s = 1.528 +- 0.019 (stat) +-
0.009 (syst) ps, which are consistent and competitive with determinations by
other experiments.Comment: 8 pages, 2 figures, Phys. Rev. Lett 109, 171802 (2012
Maladaptive Habitat Selection of a Migratory Passerine Bird in a Human-Modified Landscape
In human-altered environments, organisms may preferentially settle in poor-quality habitats where fitness returns are lower relative to available higher-quality habitats. Such ecological trapping is due to a mismatch between the cues used during habitat selection and the habitat quality. Maladaptive settlement decisions may occur when organisms are time-constrained and have to rapidly evaluate habitat quality based on incomplete knowledge of the resources and conditions that will be available later in the season. During a three-year study, we examined settlement decision-making in the long-distance migratory, open-habitat bird, the Red-backed shrike (Lanius collurio), as a response to recent land-use changes. In Northwest Europe, the shrikes typically breed in open areas under a management regime of extensive farming. In recent decades, Spruce forests have been increasingly managed with large-size cutblocks in even-aged plantations, thereby producing early-successional vegetation areas that are also colonised by the species. Farmland and open areas in forests create mosaics of two different types of habitats that are now occupied by the shrikes. We examined redundant measures of habitat preference (order of settlement after migration and distribution of dominant individuals) and several reproductive performance parameters in both habitat types to investigate whether habitat preference is in line with habitat quality. Territorial males exhibited a clear preference for the recently created open areas in forests with higher-quality males settling in this habitat type earlier. Reproductive performance was, however, higher in farmland, with higher nest success, offspring quantity, and quality compared to open areas in forests. The results showed strong among-year consistency and we can therefore exclude a transient situation. This study demonstrates a case of maladaptive habitat selection in a farmland bird expanding its breeding range to human-created open habitats in plantations. We discuss the reasons that could explain this decision-making and the possible consequences for the population dynamics and persistence
Increased Mitochondrial Calcium Sensitivity and Abnormal Expression of Innate Immunity Genes Precede Dopaminergic Defects in Pink1-Deficient Mice
BACKGROUND: PTEN-induced kinase 1 (PINK1) is linked to recessive Parkinsonism (EOPD). Pink1 deletion results in impaired dopamine (DA) release and decreased mitochondrial respiration in the striatum of mice. To reveal additional mechanisms of Pink1-related dopaminergic dysfunction, we studied Ca²+ vulnerability of purified brain mitochondria, DA levels and metabolism and whether signaling pathways implicated in Parkinson\u27s disease (PD) display altered activity in the nigrostriatal system of Pink1⁻/⁻ mice.
METHODS AND FINDINGS: Purified brain mitochondria of Pink1⁻/⁻ mice showed impaired Ca²+ storage capacity, resulting in increased Ca²+ induced mitochondrial permeability transition (mPT) that was rescued by cyclosporine A. A subpopulation of neurons in the substantia nigra of Pink1⁻/⁻ mice accumulated phospho-c-Jun, showing that Jun N-terminal kinase (JNK) activity is increased. Pink1⁻/⁻ mice 6 months and older displayed reduced DA levels associated with increased DA turnover. Moreover, Pink1⁻/⁻ mice had increased levels of IL-1β, IL-12 and IL-10 in the striatum after peripheral challenge with lipopolysaccharide (LPS), and Pink1⁻/⁻ embryonic fibroblasts showed decreased basal and inflammatory cytokine-induced nuclear factor kappa-β (NF-κB) activity. Quantitative transcriptional profiling in the striatum revealed that Pink1⁻/⁻ mice differentially express genes that (i) are upregulated in animals with experimentally induced dopaminergic lesions, (ii) regulate innate immune responses and/or apoptosis and (iii) promote axonal regeneration and sprouting.
CONCLUSIONS: Increased mitochondrial Ca²+ sensitivity and JNK activity are early defects in Pink1⁻/⁻ mice that precede reduced DA levels and abnormal DA homeostasis and may contribute to neuronal dysfunction in familial PD. Differential gene expression in the nigrostriatal system of Pink1⁻/⁻ mice supports early dopaminergic dysfunction and shows that Pink1 deletion causes aberrant expression of genes that regulate innate immune responses. While some differentially expressed genes may mitigate neurodegeneration, increased LPS-induced brain cytokine expression and impaired cytokine-induced NF-κB activation may predispose neurons of Pink1⁻/⁻ mice to inflammation and injury-induced cell death
A comprehensive overview of radioguided surgery using gamma detection probe technology
The concept of radioguided surgery, which was first developed some 60 years ago, involves the use of a radiation detection probe system for the intraoperative detection of radionuclides. The use of gamma detection probe technology in radioguided surgery has tremendously expanded and has evolved into what is now considered an established discipline within the practice of surgery, revolutionizing the surgical management of many malignancies, including breast cancer, melanoma, and colorectal cancer, as well as the surgical management of parathyroid disease. The impact of radioguided surgery on the surgical management of cancer patients includes providing vital and real-time information to the surgeon regarding the location and extent of disease, as well as regarding the assessment of surgical resection margins. Additionally, it has allowed the surgeon to minimize the surgical invasiveness of many diagnostic and therapeutic procedures, while still maintaining maximum benefit to the cancer patient. In the current review, we have attempted to comprehensively evaluate the history, technical aspects, and clinical applications of radioguided surgery using gamma detection probe technology
Vampires in the village Žrnovo on the island of Korčula: following an archival document from the 18th century
Središnja tema rada usmjerena je na raščlambu spisa pohranjenog u Državnom arhivu u Mlecima (fond: Capi del Consiglio de’ Dieci: Lettere di Rettori e di altre cariche) koji se odnosi na događaj iz 1748. godine u korčulanskom selu Žrnovo, kada su mještani – vjerujući da su se pojavili vampiri – oskvrnuli nekoliko mjesnih grobova. U radu se podrobno iznose osnovni podaci iz spisa te rečeni događaj analizira u širem društvenom kontekstu i prate se lokalna vjerovanja.The main interest of this essay is the analysis of the document from the State Archive in Venice (file: Capi del Consiglio de’ Dieci: Lettere di Rettori e di altre cariche) which is connected with the episode from 1748 when the inhabitants of the village Žrnove on the island of Korčula in Croatia opened tombs on the local cemetery in the fear of the vampires treating.
This essay try to show some social circumstances connected with this event as well as a local vernacular tradition concerning superstitions
Microcalcified Hepatic Metastases Incidentally Detected on F-18 NaF PET/CT in a Patient with Prostate Cancer
F-18 NaF PET/CT evaluation has gained importance in recent years. Achievements from F-18 NaF PET/CT are: higher sensitivity of positron imaging, higher target background ratio with higher tracer accumulation in bone hydroxyapatite and higher specificity through CT correlation. These properties have also given directions to new research fields based on imaging microcalcifications, very recently. A limited number of cases have reported the F-18 NaF uptake in macrocalcified soft tissue metastases. Although the presence of microcalcification was not proved; accumulation of F-18 NaF in the metastatic brain lesion with no visible calcification on the CT, in a patient with ductal breast carcinoma has also been reported. Herein we present a patient with microcalcified hepatic metastasis of prostate cancer incidentally detected on F-18 NaF PET/CT which was confirmed with histochemical staining
F-18 fluoride uptake in primary breast cancer
Sarikaya, Ali (Trakya author)ObjectiveBone-specific radiotracers are known to accumulate in breast lesions. Tc-99m diphosphonates have been widely studied in differentiating breast lesions. In this retrospective study, we aimed to assess the uptake of the bone-specific PET radiotracer, F-18 fluoride (NaF), in primary breast cancers to determine its sensitivity and to identify any differences in NaF uptake between calcified and non-calcified tumors, histological subtypes, and patients with or without axillary lymphadenopathy.MethodsNaF positron emission tomography/computed tomography (PET/CT) images of 69 newly diagnosed breast cancer patients were reviewed. F-18 fluoride uptake as maximum standardized uptake value (NaF SUVmax) was measured in the primary tumor, enlarged axillary lymph nodes and contralateral normal/non-tumoral breast tissue. Low-dose CT images were reviewed to locate the primary tumor and grossly assess its calcification and check for ipsilateral axillary lymphadenopathy. Whole body NaF PET/CT images were reviewed to search for bone metastases. Eighteen patients also underwent F-18 fluorodeoxyglucose (FDG) PET/CT study.ResultsThe primary breast tumor was clearly seen as focal or diffuse uptake on NaF PET images in 27 of 69 patients (39%) (mean NaF SUVmax: 2.01.0). In the rest, there was only mild bilateral diffuse breast uptake. When analyzing images per histological subtype (42 patients, 43 tumors), 14 of 31 invasive ductal carcinomas (IDC) (45%) and 3 of 4 ductal carcinoma in situ (DCIS) were visible on PET. Five invasive lobular carcinomas, 2 invasive mammary carcinomas, and 1 mucinous carcinoma were not visible on PET. Mean NaF SUVmax of contralateral normal/non-tumoral breast tissue was 1.0 +/- 0.4. There was no significant difference in mean NaF SUVmax of primary tumor in cases with and without calcification or with and without axillary lymphadenopathy (p 0.892 and 0.957). There was no correlation between NaF SUVmax and FDG SUVmax values of the primary tumors (r 0.072, p 0.797, Pearson correlation).ConclusionNaF PET has relatively low sensitivity in detecting breast cancer. However, abnormal breast uptake on NaF PET requires further evaluation. F-18 fluoride uptake in the primary breast tumor does not seem to be correlated with axillary lymphadenopathy (metastasis potential), gross tumor calcification or metabolic activity of the tumor
