Axion Search with a Quantum-Limited Ferromagnetic Haloscope.

A ferromagnetic axion haloscope searches for dark matter in the form of axions by exploiting their interaction with electronic spins. It is composed of an axion-to-electromagnetic field transducer coupled to a sensitive rf detector. The former is a photon-magnon hybrid system, and the latter is based on a quantum-limited Josephson parametric amplifier. The hybrid system consists of ten 2.1 mm diameter yttrium iron garnet spheres coupled to a single microwave cavity mode by means of a static magnetic field. Our setup is the most sensitive rf spin magnetometer ever realized. The minimum detectable field is 5.5×10^{-19} T with 9 h integration time, corresponding to a limit on the axion-electron coupling constant g_{aee}≤1.7×10^{-11} at 95% C.L. The scientific run of our haloscope resulted in the best limit on dark matter axions to electron coupling constant in a frequency span of about 120 MHz, corresponding to the axion-mass range 42.4-43.1 µeV. This is also the first apparatus to perform a wide axion-mass scanning by only changing the static magnetic field.

Risk factors for recurrent wheezing in the first year of life in the city of Córdoba, Argentina.

BACKGROUND: Wheezing is a very common respiratory symptom in infants. The prevalence of wheezing in infants, conducted in developed countries shows prevalence rates ranging between 20% and 30%. However, we do not know the risk factors in our population of wheezing infants. METHODS: A standardised written questionnaire (WQ-P1-EISL) in infants between 12 and 18 months of age residing in the city of Cordoba was used; population/sample included 1031 infants. Recurrent wheezing (RW) was defined as three or more episodes of wheezing reported by the parents during the first 12 months of life. Data obtained were coded in Epi-Info™ (version 7) and statistically analysed with SPSS (version 17.5) software in Spanish. Parametric tests (one-way ANOVA) were performed for identifying significantly associated variables. RESULTS: The prevalence of wheezing infants was 39.7%; recurrent wheezing 33%; and severe wheezing 14.7%; 13.7% had pneumonia before the first year and of these 6.3% were hospitalised, multiple variables as risk factors for wheezing were found such as: >6 high airway infections and bronchiolitis in the first three months of life, smokers who smoke in the home among other risk factors and protective factors in those who have an elevated socioeconomic status. CONCLUSION: It is known that persistent respiratory problems in children due to low socioeconomic status is a risk factor for wheezing, pneumonia and could be a determining factor in the prevalence and severity of RW in infants. Research suggests that there are areas for improvement in the implementation of new educational strategies.

Electronic structure and energy decomposition analyses as a tool to interpret the redox potential ranking of naphtho-, biphenyl- and biphenylene-quinone isomers.

By calling on modelling approaches we have performed a comparative study on the redox properties of various naphtho-, biphenyl- and biphenylene-quinone isomers. These different compounds exhibit as a whole a redox potential range between 2.09 and 2.90 V vs. Li+/Li. A specific methodology was used to decrypt the interplay among isomerism, aromaticity and antiaromaticity modifications and the stabilization/destabilization effects due to other molecular components on this key electrochemical feature for electrode materials of batteries. In particular, energy decomposition analysis, within the Quantum Theory of Atoms in Molecules, along with the electron and electron spin population changes upon reduction nicely rationalise the observed potential trends. While 1,2- and 2,3-isomers show the highest/lowest redox potential in the biphenylene-quinone series, a reverse trend is observed for the naphtho-quinone, the compound having the two carbonyl groups on distinct rings being characterized by an intermediate value in both cases. There is instead almost no differentiation between 1,2 and 2,3 isomers for the biphenyl-quinone family.

Engineering of unsubstituted quinoid-like frameworks enabling 2 V vs. Li(+)/Li redox voltage tunability and related derivatives.

A criterion for redox voltage tuning (0.96-2.96 V vs. Li(+)/Li) was derived from DFT calculations on quinoneazine and analogues (C/O replacing N). As rationalized through spin-charge distributions and energetic criteria, high-low voltage implying a bridge with delocalized-localized bond nature mainly originates from ring stabilization. Established guidelines serve to propose optimal derivatives.

Ciguatera poisonings: A global review of occurrences and trends.

Ciguatera Poisoning (CP) is the most prevalent, phycotoxin related seafood poisoning across the globe, affecting between 10,000 and 50,000 people annually. This illness results from the consumption of seafood contaminated with lipid soluble toxins known as ciguatoxins (CTXs) that are produced by benthic dinoflagellates in the genera Gambierdiscus and Fukuyoa. The present work reviews the global occurrence of CP events and outbreaks, based on both scientific and gray literature. Ciguatera prevalence is significantly underestimated due to a lack of recognition of ciguatera symptoms, limited collection of epidemiological data on a global level, and reticence to report ciguatera in CP-endemic regions. Analysis of the time-series data available for a limited number of countries indicates the highest incidence rates are consistently reported from two historical CP-endemic areas i.e., the Pacific and Caribbean regions, a situation due in part to the strong reliance of local communities on marine resources. Ciguatera-related fatalities are rare (<0.1% of reported cases). The vast majority of outbreaks involve carnivorous fish including snappers, groupers, wrasses, and barracudas. Since 2000, an expansion of the geographical range of CP has been observed in several areas like Macaronesia and east and southeast Asia. In some of these locales, random surveys confirmed the presence of CTXs in locally sourced fish, consistent with the concurrent report of novel CP incidents (e.g., Canary Islands, Madeira, Selvagens Islands, New South Wales). One characteristic of outbreaks occurring in Asia is that they often present as large disease clusters due to group consumption of a single contaminated fish. Similar observations are reported from the Indian Ocean in the form of shark poisoning outbreaks which often lead to singular types of CP characterized by a high fatality rate. Other atypical forms of CP linked to the consumption of marine invertebrates also have been documented recently. Owing to the significant health, socioeconomic and socio-cultural impacts of ciguatera, there is an urgent need for increased, standardized, coordinated efforts in ciguatera education, monitoring and research programs. Several regional and international initiatives have emerged recently, that may help improve patients' care, data collection at a global scale, and risk monitoring and management capabilities in countries most vulnerable to CP's toxic threat.

A cryogenic magneto-optical device for long wavelength radiation.

We present here a small-scale liquid helium immersion cryostat with an innovative optical setup suitable to work in long wavelength radiation ranges and under an applied magnetic field. The cryostat is a multi-stage device with several shielding in addition to several optical stages. The system has been designed with an external liquid nitrogen boiler to reduce liquid bubbling. The optical and mechanical properties of the optical elements were calculated and optimized for the designed configuration, while the optical layout has been simulated and optimized among different configurations based on the geometry of the device. The final design has been optimized for low-noise radiation measurements of proximity junction arrays under an applied magnetic field in the wavelength range λ = 250 µm-2500 µm.

High quality factor photonic cavity for dark matter axion searches.

Searches for dark matter axions involve the use of microwave resonant cavities operating in a strong magnetic field. Detector sensitivity is directly related to the cavity quality factor, which is limited, until recently, to the use of non-superconducting metals by the presence of the external magnetic field. In this paper, we present a cavity of novel design whose quality factor is not affected by a magnetic field. It is based on a photonic structure by the use of sapphire rods. The quality factor at cryogenic temperature is in excess of 5 × 105 for a selected mode.

Vibrational properties of hexagonal Ge(2)Sb(2)Te(5) from first principles.

Phonons at the Γ point and the Raman spectrum of the hexagonal Ge(2)Sb(2)Te(5) were computed within density functional perturbation theory. The three different stackings of the Ge/Sb planes proposed in the experimental literature were considered. The theoretical Raman spectrum is similar for the three stackings with a marginally better agreement with experiments for the structure proposed by Matsunaga et al (2004 Acta Crystallogr. B 60 685) which assumes a disorder in Ge/Sb site occupation. Although the large broadening of the experimental Raman peaks prevents discriminating among the different stackings, the assignment of the Raman peaks to specific phonons is possible because the main features of the spectrum are rather insensitive to the actual distribution of atoms in the Sb/Ge sublattices. On the basis of the energetics (including configurational entropy) two stackings seem plausible candidates for GST, but only the mixed stacking by Matsunaga et al reproduces the spread of Ge/Sb-Te bond lengths measured experimentally.

[Ciguatera and acute polyradiculoneuritis. Description of two cases in French Polynesia: immunoallergic hypothesis?]. / Ciguatéra et polyradiculonévrite aiguë a propos de deux cas en Polynésie française: hypothèse immuno-allergique?

Ciguatera is a foodborne poisoning caused by eating seafood from tropical and subtropical reef areas. According to official data from the local health department, cases of ciguatera in French Polynesia are estimated to involve 240 to 400 persons per 100 000 inhabitants. Associated with a wide spectrum of gastrointestinal, cardiovascular, nervous, and general signs, ciguatera is usually benign although some forms can lead to hospitalization. The purpose of this report is to describe two unusual cases involving patients who developed acute polyradiculoneuritis with Guillain-Barré-syndrome-like peripheral nervous system deficits on the seventh day of ciguatera after ingestion of moray eel. The hypothesis of an immune-allergic reaction is raised especially in the light of rapid improvement of the patient who received polyvalent immunoglobulin treatment.

Ciguatera poisoning in French Polynesia: insights into the novel trends of an ancient disease.

Ciguatera is a non-bacterial seafood poisoning highly prevalent in French Polynesia where it constitutes a major health issue and a major threat to food sustainability and food security for local populations. Ciguatera results from the bioaccumulation in marine food webs of toxins known as ciguatoxins, originating from benthic dinoflagellates in the genera Gambierdiscus and Fukuyoa. Ciguatera is characterized by a complex array of gastrointestinal, neurological and cardiovascular symptoms. The effective management of patients is significantly hampered by the occurrence of atypical forms and/or chronic sequelae in some patients, and the lack of both a confirmatory diagnosis test and a specific antidote. In addition, recent findings have outlined the implication of novel species of the causative organisms as well as new vectors, namely marine invertebrates, in ciguatera outbreaks. Another novel trend relates to the geographical expansion of this disease to previously unaffected areas, not only in certain island groups of French Polynesia but also in temperate regions worldwide, as a likely consequence of the effects of climate change.

Severe seafood poisoning in French Polynesia: a retrospective analysis of 129 medical files.

We present a retrospective study of 129 medical files concerning seafood poisonings (SFPs) registered at the central hospital of Tahiti (French Polynesia) between 1999 and 2005. Even if during that period most of the described cases (96%) concerned the ichtyosarcotoxism ciguatera, it is interesting to note that we also registered three other SFPs: tetrodotoxism, carchatoxism and lyngbyatoxism due to the consumption of tetraodon/diodon species, sharks or sea turtles, respectively. In ciguatera, cardiovascular symptoms were the primary criteria of severity with bradycardia and hypotension observed at 75% and 43%, respectively. Neurological manifestations (such as cerebellar syndrome, language troubles, diplopia or polyradiculoneuritis), trouble and/or loss of consciousness and dyspnoea were secondary criteria of severity. Body temperature was reported under 36.5 degrees C in 48 of 80 documented files. This observation, which has not previously been described in humans, may be related to possible central effects of the ingested toxin. The last remark concerns two extremely severe cases of ciguatera fish poisoning in which physicians had suspected an inflammatory neuropathy called the Guillain-Barré syndrome (GBS). Even if it is premature to conclude any correlation between the intoxication and the appearance of GBS, it is interesting to note that in both pathologies, morphological disturbances of nerve fibres have been reported.

Histochemical study of cardiac mast cells degranulation and collagen deposition: interaction with the cathecolaminergic system in the rat.

Although their role in the cardiovascular system is still largely unknown, mast cells are present in the myocardium of both experimental animals and humans. Interestingly, cathecolaminergic nerve fibres and mast cells are often described in close morphological and functional interactions in various organs. In the present study we investigated the effects of chronic interference with beta-adrenergic receptors (via either sympathectomy or beta-blockade) on cardiac mast cell morphology/activation and on interstitial collagen deposition. In rats subjected to chemical sympathectomizy with the neurotoxin 6-hydroxydopamine (6-OHDA) we observed a significant increase of mast cell density, and in particular of degranulating mast cells, suggesting a close relationship between the cardiac catecholaminergic system and mast cell activation. In parallel, chronic 6-OHDA treatment was associated with increased collagen deposition. The influence of the beta-adrenergic receptor component was investigated in rats subjected to chronic propranolol administration, that caused a further significant increase in mast cell activation associated with a lower extent of collagen deposition when compared to chemical sympathectomy. These data are the first demonstration of a close relationship between rat cardiac mast cell activation and the catecholaminergic system, with a complex interplay with cardiac collagen deposition. Specifically, abrogation of the cardiac sympathetic efferent drive by chemical sympathectomy causes mast cell activation and interstitial fibrosis, possibly due to the local effects of the neurotoxin 6-hydroxydopamine. In contrast, beta-adrenergic blockade is associated with enhanced mast cell degranulation and a lower extent of collagen deposition in the normal myocardium. In conclusion, cardiac mast cell activation is influenced by beta-adrenergic influences.

Prognostic significance of vascular endothelial growth factor protein in node-negative breast carcinoma.

BACKGROUND: The clinical outcome is generally positive for patients with node-negative breast carcinoma (i.e., those who do not have detectable metastases in the lymph nodes) who have been treated with surgery or surgery plus radiation therapy. In about 30% of the patients, however, the disease recurs, and they are at risk of death. Determination of valid new prognostic indicators would improve the ability to identify patients at high risk of recurrence. Breast cancer can entail substantial development of new blood vessels within the tumor tissue, and it is known that the growth and metastasis of solid tumors are dependent on such angiogenesis. The conversion of tumor cells to an angiogenic phenotype may be preceded by a change in the balance of angiogenic growth factors and angiogenesis inhibitors. PURPOSE: This study was conducted to determine if the levels of vascular endothelial growth factor (VEGF) protein, a potent endothelial growth factor and mediator of vascular permeability and angiogenesis, measured in the primary tumors of women with node-negative breast cancer are associated with known prognostic factors and patient survival. METHODS: By use of a selective enzymatic immunoassay, levels of VEGF protein were measured in cytosolic extracts of primary tumor tissue surgically obtained from 260 women with node-negative breast carcinoma who had been treated with surgery with or without radiation therapy but not with adjuvant therapy and who had been followed for a median time of 66 months. The relationships between VEGF concentrations and other prognostic dichotomous variables or clinical outcome were tested by the use of the Kolmogorov-Smirnov test and univariate and multivariate Cox analyses, respectively. The relationship between VEGF and hormone receptors (i.e., those for estrogen and progesterone) was examined by the use of Spearman's correlation analyses. All P values resulted from the use of two-sided statistical tests. RESULTS: Tumors from 247 (95%) of the 260 patients had detectable VEGF, ranging in concentration from 5.0 to 6523 pg/mg protein (median, 126.25 pg/mg protein). No statistically significant associations were found between VEGF and the other prognostic factors (e.g., age, menopausal status, histologic tumor type, tumor size, and hormone receptors) examined. Levels of VEGF were found to be prognostic for both relapse-free and overall survival in univariate and multivariate analyses (likelihood ratio tests; all four P values < .001). In the multivariate analysis, the first-order interaction term of VEGF and estrogen receptor was also prognostic for overall survival (likelihood ratio test; P = .05). CONCLUSIONS: The results show that cytosolic levels of VEGF in tumor tissue samples are indicative of prognosis for patients with node-negative breast carcinoma.

Subcutaneous enoxaparin following thrombolysis and intravenous unfractionated heparin in ST-elevation acute myocardial infarction: safety and efficacy of low vs full dose.

AIM: In ST-segment elevation myocardial infarction (STEMI) treated with fibrin-specific thrombolytic agents, early intravenous unfractionated heparin (UFH) is warranted. Low molecular weight heparin Enoxaparin currently represents an alternative to UFH, to be used until hospital discharge. Since optimal dosing of subcutaneous Enoxaparin is not standardized, we conducted an observational study to compare safety and efficacy of low (4,000 U once daily) vs full dose (100 U/kg twice daily) regimens. METHODS: All STEMI patients successfully treated with tenecteplase and intravenous UFH and referred to the Catheterization Laboratory between June 2002-November 2003 for predischarge coronary angiography, were evaluated. The primary end-point was the composite of hemorrhages and residual angina/reinfarction during Enoxaparin administration, whereas secondary end-points were occurrence of venous thromboembolism (VTE) during Enoxaparin administration, and infarct-related artery (IRA) patency rate at predischarge coronary angiography. RESULTS: Out of 123 patients, 57 (M/F 45/12, mean age 65.8+/-8.1 years) received low dose, and 66 (men/women 45/21, mean age 62.6+/-11.8 years) full dose subcutaneous Enoxaparin. The incidence of the composite primary end-point was comparable in both groups (19% vs 26%; P=NS). Also, null was the occurrence of VTE, whereas the IRA patency rate did not significantly differ in the 2 groups (84% vs 86% TIMI 3 and 11% vs 9% TIMI 2 flow grades; P=NS). CONCLUSIONS: In patients with STEMI undergoing successful recanalization with tenecteplase and intravenous UFH, low dose subcutaneous Enoxaparin appears preferable to full dose, in the light of comparable safety and clinical efficacy and superior easiness of use.

Binding of ethidium bromide to ribosomal RNA. Absorption, fluorescence, circular and electric dichroism study.

The interaction between ethidium bromide and ribosomal RNA has been studied by means of absorption, fluorescence, circular and electric dichroism measurements in the near ultraviolet and visible regions at low ionic strength (1 . 10(-3) and 6 . 10(-3). The results have been interpreted on the basis of a model of interaction involving the intercalation of the phenanthridinium ring of the dye in the double-stranded regions of the RNA molecule, resulting in an increase of the dye-dye interactions as compared to DNA, and a stiffening of the intercalation regions.

Interaction of ethidium bromide with ribosomes. Absorption, fluorescence, circular dichroism and sedimentation studies.

It is shown in this work that the binding of ethidium bromide to yeast ribosomes occurs through intercalation in the double-stranded rRNA regions and produces changes in the ribosomes structure, yielding unfolded subparticles, and even partial separation of proteins from rRNA at very high binding ratios. The addition of Mg2+ prevents these structural changes, probably by partial inhibition of the dye binding.

Sodium sensitivity of blood pressure in long-term detoxified alcoholics.

To investigate whether sodium sensitivity of blood pressure participates in the relationship of arterial hypertension to chronic alcohol consumption, 30 alcoholics detoxified from 6 to 12 months and 30 teetotaler controls underwent a dietary sodium manipulation study. They received a daily 55 mmol sodium diet for 7 days, followed by a 260 mmol sodium diet for 7 days. Changes in 24-hour urinary sodium excretion between the end of each period were similar in alcoholics and controls (202+/-16 SEM mmol and 227+/-11, respectively). Plasma renin activity in alcoholics was lower than in controls at both low (2.4+/-0.4 ng angiotensin I/mLxh(-1) versus 3. 7+/-0.2, P<0.003) and high sodium intake (0.47+/-0.10 versus 0. 82+/-0.10, P<0.05), with smaller variations in alcoholics (-1.9+/-0. 3 versus -2.9+/-0.2, P<0.009). In alcoholics, alteration in sodium intake was followed by greater changes in both systolic and mean blood pressure (ambulatory blood pressure monitoring), which rose by 10.6+/-2.2 mm Hg and 7.3+/-1.5 versus 4.7+/-1.4 and 3.9+/-1.0 in controls, respectively (P<0.03 for systolic and P<0.05 for mean blood pressure). The ratio of changes in mean blood pressure to those in 24-hour urinary sodium excretion was higher in alcoholics (0.044+/- 0.011 mm Hgxmmol(-1) versus 0.018+/-0.0041, P<0.005). Our data show that in detoxified alcoholics, there is an abnormal response of both blood pressure and plasma renin activity to variations in salt intake similar to that in sodium-sensitive arterial hypertension. The precise relationship between the sodium sensitivity of blood pressure in detoxified alcoholics and the long-term influence of alcohol on blood pressure remains to be elucidated.

Serine incorporation into phospholipids in vivo and serine phosphoglyceride metabolic transformations in cerebral areas from adult and aged rats.

Serine phosphoglycerides (SPG) in the nervous tissue are synthesized by base-exchange reaction. SPG may be decarboxylated and converted into ethanolamine phosphoglycerides (EPG). This latter reaction may be followed in turn by several enzymatic reactions leading to choline phosphoglycerides (CPG) via three successive methylations. These metabolic pathways are important for several reasons and their contribution to membrane phospholipid renewal has been clearly demonstrated. Base-exchange is the only metabolic route to synthesize SPG; it was therefore possible to test this pathway in vivo by injecting labeled serine. Serine incorporation into phosphoglycerides was reduced in cortex and hippocampus from aged rat brain as compared to adult, while no change in the SPG successive metabolic transformation was found. Based on both the results presented herein and previous ones obtained in vitro the authors suggest that the reduced serine incorporation may be due to reduced uptake into cells from aged animals. This finding leads to the conclusion that the above mechanisms for partial renewal of the phospholipid molecule may play an important role in the brain structure of aged animals.

Prognostic role of serum CA15.3 in 362 node-negative breast cancers. An old player for a new game.

The aims of the present investigation were to evaluate the association between serum CA15.3 levels and other biological and clinical variables and its prognostic role in patients with node-negative breast cancer. We evaluated 362 patients operated upon primary breast cancer from 1982 to 1992 (median follow-up 69 months). Serum CA15.3 was measured by an immunoradiometric assay. The association between variables was investigated by a Principal Component Analysis (PCA) and the prognostic role of CA15.3 on relapse-free survival (RFS) was investigated by Cox regression models adjusting for age, oestrogen receptor (ER), tumour stage, and ER x age interaction, with both the likelihood ratio test and Harrell's c statistic. The prognostic contribution of CA 15.3 was highly significant. Log relative hazard of relapse was constant until approximately 10 (U/ml) of CA15.3 and increased thereafter with increasing marker levels. CA15.3 showed a significant contribution using as a cut-off point a value of 31 U/ml. However, the contribution to the model of the marker as a continuous variable is much greater. From these findings, we can conclude that: (i) CA15.3 is a prognostic marker in node-negative breast cancer; (ii) its relationship with prognosis is continuous, with the risk of relapse increasing progressively from approximately 10 U/ml.