Exchange Narrowing Effects in the EPR Linewidth of Gd Diluted in Ce Compounds

Anomalous thermal behavior on the EPR linewidths of Gd impurities diluted in Ce compounds has been observed. In metals, the local magnetic moment EPR linewidth, \Delta H, is expected to increase linearly with the temperature. In contrast, in Ce_{x}La_{1-x}Os_{2} the Gd EPR spectra show a nonlinear increase. In this work, the mechanisms that are responsible for the thermal behavior of the EPR lines in Ce_{x}La_{1-x}Os_{2} are examined. We show that the exchange interaction between the local magnetic moments and the conduction electrons are responsible for the narrowing of the spectra at low temperatures. At high temperatures, the contribution to the linewidth of the exchange interaction between the local magnetic moments and the $Ce$ ions has an exponential dependence on the excitation energy of the intermediate valent ions. A complete fitting of the EPR spectra for powdered samples is obtained.Comment: 11 pages, 1 figur

Endoscopic submucosal dissection for residual rectal polyps embedded in tissue scar: a "rescue therapy" to prevent surgical intervention?

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Interval Sentinel Lymph Nodes: An Unusual Localization in Patients with Cutaneous Melanoma

Background. Recent studies have demonstrated that there exists a great variation in the lymphatic drainage in patients with malignant melanoma. Some patients have drainage to lymph nodes outside of conventional nodal basins. The lymph nodes that exist between a primary melanoma and its regional nodal basin are defined “interval nodes”. Interval node occurs in a small minority of patients with forearm melanoma. We report our experience of the Melanoma Unit of University Hospital Spedali Civili Brescia, Italy. Methods. Lymphatic mapping using cutaneous lymphoscintigraphy (LS) has become a standard preoperative diagnostic procedure to locate the sentinel lymph nodes (SLNs) in cutaneous melanoma. We used LS to identify sentinel lymph nodes biopsy (SLNB) in 480 patients. Results. From over 2100 patients affected by cutaneous melanoma, we identified 2 interval nodes in 480 patients with SLNB . The melanomas were both located in the left forearm. The interval nodes were also both located in the left arm. Conclusion. The combination of preoperative LS and intraoperative hand-held gamma detecting probe plays a remarkable role in identifying these uncommon lymph node locations. Knowledge of the unusual drainage patterns will help to ensure the accuracy and the completeness of sentinel nodes identification

Tri-critical point and suppression of the Shastry-Sutherland phase in Ce2_{2}Pd2_{2}Sn by Ni doping

Structural, magnetization and heat capacity measurements were performed on Ce$_2$(Pd$_{1-x}$Ni$_x$)$_2$Sn ($0 \leq x \leq 0.25$) alloys, covering the full range of the Mo$_2$FeB$_2$ structure stability. In this system, the two transitions observed in Ce$_2$Pd$_2$Sn (at $T_N=4.8$\,K and $T_C=2.1$\,K respectively) converge into a tri-critical point at $T_{cr}\approx 3.4$\,K for $x\approx 0.3$, where the intermediate antiferromagnetic AF phase is suppressed. The $T_N(x)$ phase boundary decrease is due to an incipient Kondo screening of the Ce-4f moments and local atomic disorder in the alloy. Both mechanisms affect the formation of Ce-magnetic dimers on which the Shastry-Sutherland lattice (SSL) builds up. On the contrary, the $T_C(x)$ transition to the ferromagnetic ground state increases as a consequence of the weakening of the AF-SSL phase. Applied magnetic field also suppresses the AF phase like in the stoichiometric compound.Comment: 6 pages, 8 figure

The respiratory rehabilitation Maugeri network service reconfiguration after 1 year of COVID-19

As part of the Italian Health Service the respiratory ICS Maugeri network were reconfigured and several in-hospital programs were suspended to be substituted by workforce and facilities reorganization for acute and post-acute COVID-19 care need. The present review shows the time course variation of respiratory ICS network in terms of admissions diagnosis and outcomes. A comparative review of the admissions and outcome measures data (anthropometric, admission diagnosis, provenience, comorbidities, disability, symptoms, effort tolerance, disease impact, length of stay and discharge destinations) over 1 year period (March 2020-March 2021) was undertaken and compared to retrospective data from a corresponding 1 year (March 2019-March 2020) period to determine the impact of the network relocation on the delivery of pulmonary specialist rehabilitation to patients with complex needs during the pandemic episode. One of the changes implemented at the respiratory Maugeri network was the relocation of the Pulmonary Rehabilitation units from its 351 beds base to a repurposed 247 beds and a reduction in total number of admitted patients (n=3912 in pre-COVID time; n=2089 in post-COVID time). All respiratory diagnosis, except COVID sequelae, decreased (chronic respiratory failure-CRF, COPD, obstructive sleep apnoea syndrome-OSAS, interstitial lung disease-ILD, tracheostomized patients and other mixed diseases decreased of 734, 705, 157, 87, 79 and 326 units, respectively). During the pandemic time, 265 post COVID sequelae with CRF were admitted for rehabilitation (12.62%), percentage of patients coming from acute hospital increased, LOS and NIV use remained stable while CPAP indication decreased. Disease impact, dyspnoea and effort tolerance as their improvements after rehabilitation, were similar in the two periods. Only baseline disability, expressed by Barthel index, seems higher in the 2 observation time as its improvement. Hospital deaths and transfers to acute hospitals were higher during pandemic crisis while home destination decreased. This review demonstrated impact of coronavirus pandemic situation, specifically the relocation of the respiratory inpatient rehabilitation wards in a huge Italian network

Evolution of quantum criticality in the system CeNi9Ge4

The heavy fermion system CeNi9Ge4 exhibits a paramagnetic ground state with remarkable features such as: a record value of the electronic specific heat coefficient in systems with a paramagnetic ground state, \gamma = C/T \simeq 5.5 J/molK^2 at 80 mK, a temperature-dependent Sommerfeld-Wilson ratio, R=\chi/\gamma, below 1 K and an approximate single ion scaling of the 4f-magnetic specific heat and susceptibility. These features are related to a rather small Kondo energy scale of a few Kelvin in combination with a quasi-quartet crystal field ground state. Tuning the system towards long range magnetic order is accomplished by replacing a few at.% of Ni by Cu or Co. Specific heat, susceptibility and resistivity studies reveal T_N \sim 0.2 K for CeNi8CuGe4 and T_N \sim 1 K for CeNi8CoGe4. To gain insight whether the transition from the paramagnetic NFL state to the magnetically ordered ground state is connected with a heavy fermion quantum critical point we performed specific heat and ac susceptibility studies and utilized the \mu SR technique and quasi-elastic neutron scattering.Comment: 8 pages, 3 figures, will be published in J.Phys.: Conf. Series (Proceedings of the International & Interdisciplinary Workshop on Novel Phenomena in Intergrated Comples Sciences: From Living to Non-living Systems, Japan, held in Kyoto, October 11-14, 2010

The failed liberalisation of Algeria and the international context: a legacy of stable authoritarianism

The paper attempts to challenge the somewhat marginal role of international factors in the study of transitions to democracy. Theoretical and practical difficulties in proving causal mechanisms between international variables and domestic outcomes can be overcome by defining the international dimension in terms of Western dominance of world politics and by identifying Western actions towards democratising countries. The paper focuses on the case of Algeria, where international factors are key in explaining the initial process of democratisation and its following demise. In particular, the paper argues that direct Western policies, the pressures of the international system and external shocks influence the internal distribution of power and resources, which underpins the different strategies of all domestic actors. The paper concludes that analysis based purely on domestic factors cannot explain the process of democratisation and that international variables must be taken into more serious account and much more detailed

Spatial biases reduce the ability of Earth system models to simulate soil heterotrophic respiration fluxes

Heterotrophic respiration (Rh) is, at a global scale, one of the largest CO2 fluxes between the Earth's surface and atmosphere and may increase in the future. The previous generation of Earth system models (ESMs) was able to reproduce global fluxes relatively well, but at that, time no gridded products were available to perform an in-depth evaluation. The capacity of the new generation of ESMs used within the Coupled Model Intercomparison Project Phase 6 (CMIP6) to reproduce this flux has not been evaluated, meaning that the realism of resulting CO2 flux estimates is unclear. In this study, we combine recently released observational data on Rh and ESM simulations to evaluate the ability of 13 ESMs from CMIP6 to reproduce Rh. Only 4 of the 13 tested ESMs were able to reproduce the total Rh flux, but spatial analysis underlined important bias compensation for most of the ESMs, which generally showed an overestimation in tropical regions and an underestimation in arid regions. To identify the main drivers of the bias, we performed an analysis of the residuals and found that mean annual precipitation was the most important driver explaining the difference between ESM simulations and observation-derived products of Rh, with a higher bias between ESM simulations and Rh products where precipitation was high. Based on our results, next-generation ESMs should focus on improving the response of Rh to soil moisture.</p

Evidence for an inhibitory effect of physiological levels of insulin on the growth hormone (GH) response to GH-releasing hormone in healthy subjects

It has been previously reported that in healthy subjects, the acute reduction of free fatty acids (FFA) levels by acipimox enhances the GH response to GHRH. In the present study, the GH response to GHRH was evaluated during acute blockade of lipolysis obtained either by acipimox or by insulin at different infusion rates. Six healthy subjects (four men and two women, 25.8 +/- 1.9 yrs old, mean +/- SE) underwent three GHRH tests (50 micrograms iv, at 1300 h) during: 1) iv 0.9% NaCl infusion (1200-1500 h) after oral acipimox administration (250 mg) at 0700 h and at 1100 h; 2) 0.1 mU.kg-1.min-1 euglycemic insulin clamp (1200-1500 h) after oral acipimox administration (250 mg at 0700 h and at 1100 h); 3) 0.4 mU.kg-1.min-1 euglycemic insulin clamp (1200-1500 h) after oral placebo administration (at 0700 and 1100 h). Serum insulin (immunoreactive insulin) levels were significantly different in the three tests (12 +/- 2, 100 +/- 10, 194 +/- 19 pmol/L, P < 0.06), plasma FFA were low and similar (0.04 +/- 0.003, 0.02 +/- 0.005, 0.02 +/- 0.003, not significant), and the GH response to GHRH was progressively lower (4871 +/- 1286, 2414 +/- 626, 1076 +/- 207 micrograms/L 120 min), although only test 3 was significantly different from test 1 (P < 0.05). Pooling the three tests together, a significant negative regression was observed between mean serum immunoreactive insulin levels and the GH response to GHRH (r = -0.629, P < 0.01). Our results indicate that in healthy subjects, acipimox and hyperinsulinemia produce a similar decrease in FFA levels and that at similar low FFA, the GH response to GHRH is lower during insulin infusion than after acipimox. These data suggest that insulin exerts a negative effect on GH release. Because the insulin levels able to reduce the GH response to GHRH are commonly observed during the day, for instance during the postprandial period, we conclude that the insulin negative effect on GH release may have physiological relevance