Evidence of Partial Seniority Conservation in the πg_{9/2} Shell for the N=50 Isotones.

The reduced transition probabilities for the 4_{1}^{+}→2_{1}^{+} and 2_{1}^{+}→0_{1}^{+} transitions in ^{92}Mo and ^{94}Ru and for the 4_{1}^{+}→2_{1}^{+} and 6_{1}^{+}→4_{1}^{+} transitions in ^{90}Zr have been determined in this experiment making use of a multinucleon transfer reaction. These results have been interpreted on the basis of realistic shell-model calculations in the f_{5/2}, p_{3/2}, p_{1/2}, and g_{9/2} proton valence space. Only the combination of extensive lifetime information and large scale shell-model calculations allowed the extent of the seniority conservation in the N=50 g_{9/2} orbital to be understood. The conclusion is that seniority is largely conserved in the first πg_{9/2} orbital.

Establishing the Maximum Collectivity in Highly Deformed N=Z Nuclei.

The lifetimes of the first excited 2^{+} states in the N=Z nuclei ^{80}Zr, ^{78}Y, and ^{76}Sr have been measured using the γ-ray line shape method following population via nucleon-knockout reactions from intermediate-energy rare-isotope beams. The extracted reduced electromagnetic transition strengths yield new information on where the collectivity is maximized and provide evidence for a significant, and as yet unexplained, odd-odd vs even-even staggering in the observed values. The experimental results are analyzed in the context of state-of-the-art nuclear density-functional model calculations.

Effect assessment of reclaimed water and carbamazepine exposure on the thyroid axis of X. laevis: Apical and histological effects.

There is increasing environmental concern about the constant presence of pharmaceuticals and personal care products (PPCPs) in surface water, generally attributed to water discharge from wastewater treatment plants (WWTPs) that are unable to completely remove these compounds. The slight, but continuous, presence of these contaminants in reclaimed water (RW) poses a risk of chronic and sublethal toxicity, and the thyroid axis can likely be a target of many of these PPCPs. In this work, we addressed the effects of RW on the Xenopus laevis thyroid system. The Amphibian Metamorphosis Assay (AMA test) was used with modifications by exposing X. laevis tadpoles to RW samples, and to RW spiked with carbamazepine (CBZ) at 100 and 1000 higher than the average levels environmentally relevant (RW 100× and RW 1000×, respectively). Carbamazepine was selected because it is considered a marker of anthropogenic pollution and could have a potential effect on the thyroid axis. The morphological endpoints and histological alterations to the thyroid gland were evaluated. The results suggested the stimulation of the thyroid gland from exposures to the RW samples, supported by tadpoles' accelerated development and by the histological alterations observed in the thyroid gland. Developmental acceleration was also seen in the tadpoles exposed to the RW-100× and -1000× samples at comparable levels to those seen in exposures to RW samples alone. Hence CBZ did not seem to increase the effects of RW on the thyroid axis. Overall, our results suggested endocrine effects of these RW samples regardless of the CBZ concentration.

Isospin Properties of Nuclear Pair Correlations from the Level Structure of the Self-Conjugate Nucleus

The low-lying energy spectrum of the extremely neutron-deficient self-conjugate (N=Z) nuclide _{44}^{88}Ru_{44} has been measured using the combination of the Advanced Gamma Tracking Array (AGATA) spectrometer, the NEDA and Neutron Wall neutron detector arrays, and the DIAMANT charged particle detector array. Excited states in ^{88}Ru were populated via the ^{54}Fe(^{36}Ar,2nγ)^{88}Ru^{*} fusion-evaporation reaction at the Grand Accélérateur National d'Ions Lourds (GANIL) accelerator complex. The observed γ-ray cascade is assigned to ^{88}Ru using clean prompt γ-γ-2-neutron coincidences in anticoincidence with the detection of charged particles, confirming and extending the previously assigned sequence of low-lying excited states. It is consistent with a moderately deformed rotating system exhibiting a band crossing at a rotational frequency that is significantly higher than standard theoretical predictions with isovector pairing, as well as observations in neighboring N>Z nuclides. The direct observation of such a "delayed" rotational alignment in a deformed N=Z nucleus is in agreement with theoretical predictions related to the presence of strong isoscalar neutron-proton pair correlations.

Sublingual microcirculation in pancreatico-biliary surgery: An observational study.

BACKGROUND: An observational cohort study was conducted to identify potential sublingual microcirculation parameters as a target for goal-directed fluid therapy. METHODS: Patients that were scheduled for an open elective pancreatico-biliary surgery in Erasmus Medical Center were included. All patients underwent sublingual microcirculatory measurement at three time points: one day before surgery (T0), within the first 24 hours after surgery (T1) and on the fourth day after surgery (T2). The following parameters were obtained: microvascular flow index (MFI (AU)), Total vessels density (TVD (mm/mm2/)), Perfused vessels density (PVD (mm/mm2)), and proportion of perfused vessels (PPV (%)). RESULTS: Sixteen patients were included in the final analysis. The differences between the time points T1 and T0 in patients without clinical significant complication and in patients with these complications gave a significant difference for PVD small vessels (PVDs) (delta PVDs mean -0.1 vs -8.2, p=0.01) and PPV small vessels (PPVs) (delta PPVs median 7.0 % vs -15.5 %, p=0.01). CONCLUSION: The most significant microcirculatory parameter for a perioperative complicated course is the change of PVD and PPV. In the first 24 hours after surgery, if these parameters decrease there is a high chance of a complicated perioperative course.

Patients with chronic mesenteric ischemia have an altered sublingual microcirculation.

BACKGROUND: Little is known about the microcirculatory alterations in patients with chronic mesenteric ischemia (CMI). We hypothesized that patients with CMI have an impaired microcirculatory function and show an oral microcirculatory response after caloric challenge compared to healthy controls. METHODS: All patients and controls received the standard workup for CMI. Sublingual micro-circulation was evaluated before (T0) and 20 minutes after (T1) feeding. The total vessel density (TVD; mm/mm2), perfused vessel density (PVD; mm/mm2), proportion of perfused vessels (PPV; %) and microvascular flow index (MFI; AU) were assessed. RESULTS: We included 12 patients (63.2 years [IQR 48.8-70.4 years], 67% males) and 12 controls (32.7 years [IQR 27.7-38.1 years], 42% males). At baseline, patients with CMI had a decreased PPV of the sublingual small vessels (median 84.8% vs 95.7%, P=0.006), PPV of all vessels (PPV median 85.4% vs 95.3%, P=0.007) and microvascular flow index of all vessels (MFIa; median 3.00 vs 2.80, P=0.039) compared to healthy controls. After caloric challenge, PVD increased significantly in both small vessels (perfused vessel density of the small vessels [PVDs]) and all vessels (perfused vessel density of all vessels [PVDa]; PVDs [T0]) median 16.3 [IQR 13.3-22.1] vs [T1] median 19.9 [IQR 14.2-26.2], P=0.008; PVDa [T0] median 19.1 [IQR 16.2-23.6] vs [T1] median 22.2 [IQR 16.5-28.9], P=0.02; proportion of perfused vessels of the small vessels (PPVs; [T0] median 84.8% [IQR 75.3-90.4] vs [T1] median 91.0% [IQR 80.1-93.8], P=0.010). In contrast, no significant changes in microcirculatory parameters were observed after caloric challenge in healthy controls. CONCLUSION: Patients with CMI have an impaired sublingual microcirculation at baseline and show a significant response in the sublingual microcirculation after caloric challenge, whereas healthy controls have a normal microcirculation at baseline and show no reactive response upon a caloric challenge as seen in CMI patients. Sublingual microcirculation visualization may offer a rapid noninvasive method to identify patients at risk for having CMI.

Lifetime Measurements of Excited States in

Lifetimes of the first excited 2^{+} and 4^{+} states in the extremely neutron-deficient nuclide ^{172}Pt have been measured for the first time using the recoil-distance Doppler shift and recoil-decay tagging techniques. An unusually low value of the ratio B(E2:4_{1}^{+}→2_{1}^{+})/B(E2:2_{1}^{+}→0_{gs}^{+})=0.55(19) was found, similar to a handful of other such anomalous cases observed in the entire Segré chart. The observation adds to a cluster of a few extremely neutron-deficient nuclides of the heavy transition metals with neutron numbers N≈90-94 featuring the effect. No theoretical model calculations reported to date have been able to explain the anomalously low B(E2:4_{1}^{+}→2_{1}^{+})/B(E2:2_{1}^{+}→0_{gs}^{+}) ratios observed in these cases. Such low values cannot, e.g., be explained within the framework of the geometrical collective model or by algebraic approaches within the interacting boson model framework. It is proposed that the group of B(E2:4_{1}^{+}→2_{1}^{+})/B(E2:2_{1}^{+}→0_{gs}^{+}) ratios in the extremely neutron-deficient even-even W, Os, and Pt nuclei around neutron numbers N≈90-94 reveal a quantum phase transition from a seniority-conserving structure to a collective regime as a function of neutron number. Although a system governed by seniority symmetry is the only theoretical framework for which such an effect may naturally occur, the phenomenon is highly unexpected for these nuclei that are not situated near closed shells.

Neutron Skin Effects in Mirror Energy Differences: The Case of

Energy differences between analogue states in the T=1/2 ^{23}Mg-^{23}Na mirror nuclei have been measured along the rotational yrast bands. This allows us to search for effects arising from isospin-symmetry-breaking interactions (ISB) and/or shape changes. Data are interpreted in the shell model framework following the method successfully applied to nuclei in the f_{7/2} shell. It is shown that the introduction of a schematic ISB interaction of the same type of that used in the f_{7/2} shell is needed to reproduce the data. An alternative novel description, applied here for the first time, relies on the use of an effective interaction deduced from a realistic charge-dependent chiral nucleon-nucleon potential. This analysis provides two important results: (i) The mirror energy differences give direct insight into the nuclear skin; (ii) the skin changes along the rotational bands are strongly correlated with the difference between the neutron and proton occupations of the s_{1/2} "halo" orbit.

Quadrupole transition strength in the (74)Ni nucleus and core polarization effects in the neutron-rich Ni isotopes.

The reduced transition probability B(E2;0(+)→2(+)) has been measured for the neutron-rich nucleus (74)Ni in an intermediate energy Coulomb excitation experiment performed at the National Superconducting Cyclotron Laboratory at Michigan State University. The obtained B(E2;0(+)→2(+))=642(-226)(+216) e(2) fm(4) value defines a trend which is unexpectedly small if referred to (70)Ni and to a previous indirect determination of the transition strength in (74)Ni. This indicates a reduced polarization of the Z=28 core by the valence neutrons. Calculations in the pfgd model space reproduce well the experimental result indicating that the B(E2) strength predominantly corresponds to neutron excitations. The ratio of the neutron and proton multipole matrix elements supports such an interpretation.

Hindered Gamow-Teller decay to the odd-odd N=Z (62)Ga: absence of proton-neutron T=0 condensate in A=62.

Search for a new kind of superfluidity built on collective proton-neutron pairs with aligned spin is performed studying the Gamow-Teller decay of the T=1, J(π)=0+ ground state of (62)Ge into excited states of the odd-odd N=Z nucleus (62)Ga. The experiment is performed at GSI Helmholtzzentrum für Shwerionenforshung with the (62)Ge ions selected by the fragment separator and implanted in a stack of Si-strip detectors, surrounded by the RISING Ge array. A half-life of T1/2=82.9(14) ms is measured for the (62)Ge ground state. Six excited states of (62)Ga, populated below 2.5 MeV through Gamow-Teller transitions, are identified. Individual Gamow-Teller transition strengths agree well with theoretical predictions of the interacting shell model and the quasiparticle random phase approximation. The absence of any sizable low-lying Gamow-Teller strength in the reported beta-decay experiment supports the hypothesis of a negligible role of coherent T=0 proton-neutron correlations in (62)Ga.

New isomers in the full seniority scheme of neutron-rich lead isotopes: the role of effective three-body forces.

The neutron-rich lead isotopes, up to (216)Pb, have been studied for the first time, exploiting the fragmentation of a primary uranium beam at the FRS-RISING setup at GSI. The observed isomeric states exhibit electromagnetic transition strengths which deviate from state-of-the-art shell-model calculations. It is shown that their complete description demands the introduction of effective three-body interactions and two-body transition operators in the conventional neutron valence space beyond (208)Pb.

Occurrence of pharmaceutically active compounds in surface waters of the Henares-Jarama-Tajo River system (Madrid, Spain) and a potential risk characterization.

The Henares-Jarama-Tajo river system is the largest drainage basin in the Province of Madrid, Spain. This area is characterized by the presence of intensive urban and industrial activities influenced by a continental Mediterranean climate with rainfalls presenting substantial fluctuations along the different seasons. This research aimed to monitor seasonal variations in concentrations of 22 pharmaceutically active compounds (PhACs) in this river system and to establish the potential risk of sublethal effects on aquatic organisms. A total of 10 sampling sites were selected along the river system with samples collected in each of the four seasons during a year-round schedule. Most of the PhACs detected were present in sampling sites downstream in the vicinity of the most populated cities (i.e. Madrid, Guadalajara and Alcalá de Henares). Only two PhACs, fluoxetine and paraxantine, were detected in all sites regardless of the season, and showed median (+/- interquartile range) concentrations of 21.4 (+/-31.2) ng L(-1) and 8.5 (+/-5.3) ng L(-1), respectively. Other PhACs were detected with a frequency >80% and included, caffeine, diphenylhydantoin, hydrochlorotiazide, ibuprofen, ketoprofen, diclofenac, sulfamethoxazole, atenolol, naproxen, carbamazepine and propanolol. Seasonal variations were observed with the highest concentrations in December and the lowest in September. By combining measured environmental concentrations with toxicity data (either publicly available or obtained experimentally in our laboratory), and by calculating an Maximum Risk Index (MaxRI) that each combination of PhACs should have for non exceeding the risk threshold, a high potential for long-term risk (MaxRI<10) was estimated for most of the sampling sites and sampling dates. This research allowed the characterization of the potential risk for each of the PhACs to exert sublethal effects on aquatic organisms using acute screening methods, justifying the need for chronic data in order to refine the risk of these compounds to aquatic organisms.

Stage-specific toxicity of cypermethrin to medaka (Oryzias latipes) eggs and embryos using a refined methodology for an in vitro fertilization bioassay.

Using original artificial fertilization methods with medaka (Oryzias latipes), the effects of exposure to cypermethrin on gametes, fertilization, and embryonic development were investigated. The relative sensitivity was studied with 96-hour duration, 24-hour renewal exposures to six nominal concentrations of cypermethrin ranging from 3.1 100.0 microg cypermethrin/L. Tests were initiated at different developmental stages: unfertilized egg (stage 0), late morula (stage 9), eminence of swim bladder (stage 29), and maximum flexion of the atrioventricular region (stage 34). Cypermethrin did not affect the fertilization process. Predominant sublethal effects in embryos included transient visceral edemas intimately associated to the gall bladder with subsequent pericardial edemas. Other sublethal effects were observed in surviving larvae and included spastic movements with or without ability to respond to stimulus (>/=6.3 microg cypermethrin/L), spinal curvatures, and delayed or absence of swim bladder inflation (>/=12.5 microg cypermethrin/L). The exposure of the gametes (stage 0) or animals during earlier embryonic development (stages 9 or 29) was not a critical window for cypermethrin exposure. Although the incidence of edemas in embryos occurred mainly during exposure of these early developmental stages, embryo and larva lethality and the incidence of transient sublethal effects in hatchlings showed that the later exposure window (stage 34) was the most sensitive. The stage 34 group involved advanced organogenetic stages in which the chorion partially degraded before hatching. Our studies reinforced the idea that a combination of morphologic and functional impairment evaluation is a more sensitive response to developmental toxicants than morphologic defects alone.