1,085 research outputs found
Intravitreal injection of Ozurdex(Âź) implant in patients with persistent diabetic macular edema, with six-month follow-up
AIM:
To evaluate the efficacy of intravitreal dexamethasone injections in diabetic macular edema (DME).
METHODS:
A 700 ÎŒg slow-release intravitreal dexamethasone implant (OzurdexÂź) was placed in the vitreal cavity of 17 patients (19 eyes) affected with persistent DME. Best corrected visual acuity (BCVA) was assessed through Early Treatment Diabetic Retinopathy Study (ETDRS). Central macular thickness (CMT) was measured by spectral-domain optical coherence tomography. BCVA and CMT examinations were carried out at baseline (T0) and repeated after three days, one month (T1), three months (T3), four months (T4), and six months (T6) post injection.
RESULTS:
Dexamethasone implant induced an improvement in ETDRS at T1, T3, T4, and T6 post injection. CMT was reduced at T1, T3, and T4, while at T6, CMT values were not statistically different from baseline. No complications were observed during the follow-up.
CONCLUSION:
Our data suggest that dexamethasone implant is effective in reducing DME symptoms within a six-month frame
Thermally induced behavior of the K-exchanged erionite. A further step in understanding the structural modifications of the erionite group upon heating
Fibrous erionite is a naturally occurring zeolite considered to be highly carcinogenic upon inhalation, even more than crocidolite. Since no iron is typically present in erionite, its toxicity has been attributed to ion-exchanged Fe participating in Fenton chemistry. Recently, a study aimed at investigating possible fiber inactivation routes surprisingly showed that, despite having completely occluded all available pores with K ions, the erionite-Na sample preserved the property to upload Fe (II) within the structure. In this work, the thermal behavior of the K-exchanged erionite-Na was investigated by TG/ DSC and in situ XRPD analyses in order to provide relevant information for modeling the thermally induced behavior of the erionite group. Rietveld refinement results evidenced a general trend of cell parameters and volume with temperature similar to that observed for erionite-K from Rome (Oregon, USA). However, the dependence of Tdehydrand Tbreakfrom Si/Si+Al ratio observed in zeolites (high Si content favours a lower Tdehydrand a higher Tbreak) is not observed, possibly due to the effect of the relevant amount of large K ions dispersed within the erionite cage, acting as reinforcing blocks for the framework. Heating produces a progressive emptying of the Ca sites, common effect previously observed in erionite samples showing different chemistry. In addition, K1 s.s. remains unchanged evidencing the absence of any âinternal ion exchangeâ process, whereas s.s. at K2 increases in the range 438-573 K and then slowly decreases in the range 700-1218 K. Both Rietveld and DSC data suggest the motion of K ions from OW sites toward the walls of the erionite cavity during dehydration
Fast 2-D soft X-ray imaging device based on micro pattern gas detector
Abstract An innovative fast system for X-ray imaging has been developed at ENEA Frascati (Italy) to be used as diagnostic of magnetic plasmas for thermonuclear fusion. It is based on a pinhole camera coupled to a Micro Pattern Gas Detector (MPGD) having a Gas Electron Multiplier (GEM) as amplifying stage. This detector (2.5 cm Ă 2.5 cm active area) is equipped with a 2-D read-out printed circuit board with 144 pixels (12 Ă 12), with an electronic channel for each pixel (charge conversion, shaping, discrimination and counting). Working in photon counting mode, in proportional regime, it is able to get X-ray images of the plasma in a selectable X-ray energy range, at very high photon fluxes (106 ph s - 1mmâ2 all over the detector) and high framing rate (up to 100 kHz). It has very high dynamic range, high signal to noise ratio (statistical) and large flexibility in the optical configurations (magnification and views on the plasma). The system has been tested successfully on the Frascati Tokamak Upgrade (FTU), having central electron temperature of a few keV and density of 1020 mâ3, during the summer 2001, with a one-dimensional perpendicular view of the plasma. In collaboration with ENEA, the Johns Hopkins University (JHU) and Princeton Plasma Physics (PPPL), this system has been set up and calibrated in the X-ray energy range 2â8 keV and it has been installed, with a two-dimensional tangential view, on the spherical tokamak NSTX at Princeton. Time resolved X-ray images of the NSTX plasma core have been obtained. Fast acquisitions, performed up to 50 kHz of framing rate, allow the study of the plasma evolution and its magneto-hydrodynamic instabilities, while with a slower sampling (a few kHz) the curvature of the magnetic surfaces can be measured. All these results reveal the good imaging properties of this device at high time resolution, despite of the low number of pixels, and the effectiveness of the fine controlled energy discrimination
Whistleblowing in the Compliance Era
International events over the last year have propelled theimportance of whistleblowers to the forefront. It is increasinglyevident that whistleblowers provide immense value to society.Yet, for years, whistleblowers have been victims of retaliation,commonly experiencing threats, discrimination, andemployment termination due to their reporting. Against thebackdrop of a society heavily defined by compliance-focusedinitiativesâwhere organizations and industries constructrobust compliance programs, internal policies, and codes ofconductâthis Article highlights a significant gap in legalprotections for would-be whistleblowers. While complianceinitiatives demonstrate that active self-regulation isincreasingly a staple of organizational governance, this Articlepinpoints the problems that arise when such initiatives extendbeyond applicable legal thresholds for retaliation protection.This over-extension leaves vulnerable employees and potentialwhistleblowers without legal recourse following adverseemployment actions, even if they comply with their employersâ
internal policies and compliance programs. We examine thisgap in legal protections in the context of compliance initiativesin three domains: equal employment opportunity and sexualharassment; securities fraud; and anti-corruption. We thencompare these initiatives with the legal and regulatorycompliance postures under Title VII of the Civil Rights Act of1964, the DoddâFrank Wall Street Reform and ConsumerProtection Act, and the Foreign Corrupt Practices Act,respectively, to illustrate how most compliance initiatives failto mirror the retaliation protections under those statutes. Toremedy this gap in protections, we propose complementarysolutions under contract and tort law frameworks, coupledwith soft law initiatives
Cyber-physical systems (CPS) in supply chain management: From foundations to practical implementation
Since 2015 developments such as Industry 4.0 and cyber-physical production systems on the technology side, and approaches such as flexible and smart manufacturing systems hold great potential. These in turn give rise to special requirements that the production planning, control and monitoring, among others, needing a paradigm shift to exploit the full potential of these methods and techniques. Starting from foundations in Cyber Physical Systems (CPS), building upon definitions and findings reported by literature, a practical example of innovative Cyber Physical Supply Chain Planning System (CPS2) is provided. The paper clarifies the advantages of cyber-physical systems in the production planning, controlling and monitoring perspective with respect to manufacturing, logistics and related planning practices. A set of basic features of CPS2 systems are discussed and addressed by contextualizing service orientation architecture and microservices components with respect to supply chain management collaboration and cooperation practices. The identification of specific technologies behind those functions, within the developed research, provides some practical insight if the interesting CPS2 potential
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Interactions amongst Local and Global Drivers of Coastal Acidification in Estuarine Habitats of the Northern California Current
The variability of coastal carbonate chemistry continues to provide significant hurdles for understanding interactions between anthropogenic and natural CO2 cycling and resultant effects on coastal acidification dynamics. Attribution of the anthropogenic component is vital for identifying the impacts of increasing atmospheric carbon on coastal habitats such as coral reefs, upwelling margins, inland seas, and estuaries. The dynamic nature of these systems has led some to conclude that the baseline shift in atmospheric CO2 is a relatively unimportant driver, but emerging evidence of rapidly acidifying coastal systems suggests otherwise. This dissertation addresses natural and anthropogenic inorganic carbon cycling interactions on diel, seasonal, and decadal time scales to determine current and future acidification trajectories in estuary habitats typical of the northern California Current. Chapter 2 focuses on alterations of diel-scale âcarbonate weatherâ and accelerated rates of acidification in a seagrass habitat resulting from interactions between metabolic CO2 cycling and rising atmospheric CO2 levels. Chapter 3 quantifies how the seasonal variability of carbonate chemistry in two seagrass habitats is altered by rising atmospheric CO2, and how these alterations compare with perturbations driven by altered river discharge, warming temperatures, and eutrophication. Chapter 4 investigates the temporal and spatial dynamics of coastal acidification drivers in a small, open-coast estuary subject to seasonal upwelling and inputs from an agriculturally-developed watershed. This work shows that estuarine habitats are often poorly-buffered against increasing global atmospheric CO2 levels, resulting in accelerated changes of extreme carbonate weather and enhanced CO2 seasonality. Current and future acidification trajectories are significantly modulated by local biophysical processes, including net community metabolism and watershed chemistry. While these local processes control the variance of acidification trajectories amongst estuarine systems, our results suggests the global atmospheric CO2 perturbation is likely the dominant anthropogenic driver of coastal acidification in many systems. Management and policymaking for coastal acidification impacts will be more effective if the spatial and temporal interactions between local and global drivers of acidification are properly accounted for
Autonomic dysfunction is associated with disease progression and survival in amyotrophic lateral sclerosis: a prospective longitudinal cohort study
Background: Among non-motor symptoms, autonomic disturbances have been described in amyotrophic lateral sclerosis (ALS) and reported as mild to moderate in up to 75% of patients. However, no study has systematically investigated autonomic symptoms as prognostic factors. Objectives: The main aim of this longitudinal study was to examine the association of autonomic dysfunction with disease progression and survival in ALS. Methods: We enrolled newly diagnosed ALS patients and a healthy control group (HC). Time from disease onset to disease milestone (Kingâs stage 4) and death were calculated to assess disease progression and survival. Autonomic symptoms were assessed by a dedicated questionnaire. Longitudinal evaluation of parasympathetic cardiovascular activity was performed by the heart rate variability (HRV). Multivariable Cox proportional hazards regression models on the risk of the disease milestone and death were used. A mixed-effect linear regression model was used to compare autonomic dysfunction with a HC group as well as its impairment over time. Results: A total of 102 patients and 41 HC were studied. ALS patients, compared with HC, complained of more autonomic symptoms, especially in bulbar onset patients. Autonomic symptoms occurred in 69 (68%) patients at diagnosis and progressed over time (post-6: p = 0.015 and post-12: p < 0.001). A higher autonomic symptom burden was an independent marker of faster development of Kingâs stage 4 (HR 1.05; 95% CI 1.00â1.11; p = 0.022); whereas, urinary complaints were independent factors of a shorter survival (HR 3.12; 95% CI 1.22â7.97; p = 0.018). Moreover, HRV in ALS patients was lower than in HC (p = 0.018) and further decreased over time (p = 0.003), implying a parasympathetic hypofunction that progressed over time. Conclusion: Autonomic symptoms occur in most of the ALS patients at diagnosis and progress over time, implying that autonomic dysfunction represents an intrinsic non-motor feature of the disease. A higher autonomic burden is a poor prognostic factor, associated with a more rapid development of disease milestones and shorter survival
Surface and Bulk Modifications of Fibrous Erionite in Mimicked Gamble's Solution at Acidic pH
This study aimed at investigating both the surface and bulk modifications occurring on fibrous erionite during leaching in a mimicked Gamble's solution (MGS) at pH of 4.5 and T = 37 degrees C, up to one month of incubation. Samples were characterized by a multi-analytical approach: field-emission scanning electron microscopy (FE-SEM) was employed to investigate the morphological changes of both pristine and reacted fibres, inductively coupled plasma optical emission spectrometry (ICP-OES) was used to measure the concentration of the released cations; X-ray photoelectron spectroscopy (XPS) was exploited for highlighting possible modifications of surface chemistry; X-ray powder diffraction (XRPD) and high-resolution transmission electron microscopy (HR-TEM) were applied aiming to get information on the structural state of the fibres following the incubation. ICP results integrated with those obtained by both bulk- and surface-chemical characterization highlighted that erionite binds Na especially in the first 24 h of sample incubation in the MGS, following ion exchange with the extra framework cations, in particular Ca. Moreover, our new results show that the Na binding process caused structural modifications with the migration of Na toward the Ca2 site and redistribution of the cations within the erionite cage. TEM investigation pointed out that the interaction between erionite and MGS results in the formation of a new surface amorphous layer with an irregular lobate pattern on an earlier surface weathered layer. However, the silicate framework is not weakened by incubation in the MGS at acidic pH. In addition, on the basis of the Si release normalized to the mineral surface area, fibrous erionite resulted significantly more biodurable than amphibole asbestos. Notably, considering the primary role played by biodurability in inducing pathogenicity, this result certainly supports in vivo observations showing that erionite is much more tumorigenic than asbestos. Moreover, the ions released by erionite when immersed in MGS may trigger biological effects, such as those on lipid packing and membrane permeability. On this basis, we expect a regulatory definition that would provide protection from this carcinogenic fibre
Action minimizing orbits in the n-body problem with simple choreography constraint
In 1999 Chenciner and Montgomery found a remarkably simple choreographic
motion for the planar 3-body problem (see \cite{CM}). In this solution 3 equal
masses travel on a eight shaped planar curve; this orbit is obtained minimizing
the action integral on the set of simple planar choreographies with some
special symmetry constraints. In this work our aim is to study the problem of
masses moving in \RR^d under an attractive force generated by a potential
of the kind , , with the only constraint to be a simple
choreography: if are the orbits then we impose the
existence of x \in H^1_{2 \pi}(\RR,\RR^d) such that q_i(t)=x(t+(i-1) \tau),
i=1,...,n, t \in \RR, where . In this setting, we first
prove that for every d,n \in \NN and , the lagrangian action
attains its absolute minimum on the planar circle. Next we deal with the
problem in a rotating frame and we show a reacher phenomenology: indeed while
for some values of the angular velocity minimizers are still circles, for
others the minima of the action are not anymore rigid motions.Comment: 24 pages; 4 figures; submitted to Nonlinearit
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