We present a novel experimental study on solid CH2DOH pure and in astrophysical relevant mixtures. Solid samples were accreted under ultra high vacuum conditions at 17 K and were analyzed by ...mid-infrared transmission spectroscopy. Refractive index, density, and mid-IR band strength values were measured for pure solid CH2DOH. The refractive index was also measured for CH2DOH:H2O, CH2DOH:CO, and CH2DOH:CH3OH mixtures. For all samples, the thermal evolution of the main band profile was studied. We used the interference laser technique (HeNe laser, λ = 543.5 nm) to measure the samples thickness and a numerical method to measure the refractive index starting from the amplitude of the interference curve. We obtained the ice density through the Lorentz-Lorenz relation. To calculate the band strength values we used the linear fit of the integrated band intensities with respect to the column densities. Samples deposited at 17 K were warmed up to their sublimation temperature. Spectra were taken at selected temperatures to study their thermal evolution. The results are discussed in view of their relevance for the interpretation of astronomical IR spectra.
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•Refractive index and density measured for solid CH2DOH, CH3OH, CD3OD•Band strength measured for the main CH2DOH vibration modes in solid phase•Profile of the C-D stretching mode band studied at different temperature and mixtures•C-D stretching mode bands can be used to search for solid CH2DOH in space.
Context. Multi-year laboratory experiments have demonstrated that frozen icy mixtures containing simple organic and inorganic molecules (such as H2O, N2, CH4, CO, CO2, C2H6, etc.), if exposed to a ...flux of energetic ions or UV photons, give rise to new more complex molecules at low temperatures (10–50 K). A fraction of the new synthesized molecules is volatile while the remaining fraction is refractory and therefore it is preserved after the warm-up of the substrate to room temperature. Moreover, a part of the refractory material is formed during the annealing to room temperature, when molecules and radicals into the processed ice become mobile and react to form non-volatile molecules. By means of similar mechanisms, complex organic materials may be formed on the icy surfaces of some objects in the outer solar system, such as trans-Neptunian objects, comets and some satellites of the giant planets: in fact the interaction with solar wind and solar flares ions, solar photons and galactic cosmic rays could produce more refractory materials, analogous to those produced in the laboratory. In some cases, the materials thus synthesized may contain functional groups considered relevant to the pre-biotic chemistry in the hypothesis that interplanetary dust particles, comets and meteoroids contributed to seed the early Earth with the building blocks of life. Aims. The aim of this work is to investigate the chemical similarities and differences between some organic residues left over after ion bombardment (200 keV H+) of different ice mixtures followed by subsequent warm up under vacuum to room temperature. Methods. Seven organic residues have been prepared in our laboratory following a procedure involving the proton irradiation of seven different icy mixtures and their warm-up to room temperature. All the organic samples were characterized by FTIR spectroscopy with measurements performed in situ, in the ultra-high vacuum condition preventing any sample degradation. Three of them were selected to be characterized by XPS spectroscopy as well. Results. Among the organic residues presented in this paper, only those containing nitrogen and carbon exhibit the multi-component band centred at 2200 cm−1. This multi-component band presents interest from the astrobiological point of view due to its attribution to nitriles (–C≡N) and isonitriles (–N≡C). Our results demonstrate that this band is present in the IR spectra of organic nitrogen residues regardless the use of oxygen-bearing species in the icy mixture. This finding is of interest since the 2200 cm−1 band has been observed in some extraterrestrial samples (micro-meteorites) collected in the Antarctica.
Greater than 75% of arthroplasty surgeons report having been the subject of a malpractice lawsuit. Despite this, few studies have analyzed the causes of litigation following total joint arthroplasty ...in the United States.
This study is a retrospective analysis of malpractice lawsuits following total hip and knee arthroplasty using VerdictSearch, a database encompassing legal cases compiled from February 1988 to May 2015. Complications leading to litigation were categorized and assessed for patient, surgeon, and lawsuit factors. All monetary awards were reflected for inflation.
A total of 213 lawsuits were analyzed (119 total hip and 94 total knee arthroplasty cases). Overall, 15.0% of cases ended in settlement and 29.6% ended in a verdict in favor of the plaintiff (physician loss). The average payment for cases lost in court ($1,929,822 ± $3,679,572) was significantly larger than cases that ended in settlement ($555,347 ± $822,098) (P = .006). The most common complication following hip arthroplasty was “nerve injury” (29 cases, settlement rate: 10.3%, physician loss rate: 53.9%, and average payment: $1,089,825). The most common complication following knee arthroplasty was “pain or weakness” (17 cases, settlement rate: 5.9%, physician loss rate: 6.3%, and average payment: $451,867). Technical complications were the most likely complications to result in a physician loss (P = .019).
While complications like “pain and weakness” are less likely to result in favorable litigation for patients, the presence of an objective technical complication or nerve injury was associated with an increased risk of a physician loss and a higher payment.
STUDY DESIGN.Retrospective cohort study.
OBJECTIVE.Analyze medical malpractice verdicts and settlements associated with incidental durotomy.
SUMMARY OF BACKGROUND DATA.Incidental durotomy is a common ...complication of spine surgery. Although most intraoperative dural tears are repaired without sequelae, persistent Cerebrospinal Fluid leak, infection, or neurological injury can yield adverse outcomes. The medicolegal implications of incidental durotomy are poorly understood.
METHODS.Three separate, large legal databases were queried for cases involving incidental durotomy. Case, plaintiff, procedure, and outcome characteristics were analyzed.
RESULTS.In total, 48 dural tear-related medical malpractice cases were analyzed. Most cases (56.3%) resulted in a ruling in favor of the defendant physician. Most cases alleged neurological deficits (86.7%). A large majority of cases without neurological sequelae had an outcome in favor of the defendant (83.3%). For cases involving a payment, the average amount was $2,757,298 in 2016 adjusted dollars. Additional surgery was required in 56.3% of cases, a delay in diagnosis/treatment of durotomy was present in 43.8%, and alleged improper durotomy repair was present in 22.9%. A favorable outcome for the plaintiff was more likely in cases with versus without alleged delay in diagnosis/treatment (61.9% vs. 29.6%, P = 0.025) and improper durotomy repair technique (72.7% vs. 35.1%, P = 0.040). Repeat surgery was not associated with favorable outcome for the plaintiff (42.8% cases with reoperation vs. 38.1% without, P = 0.486).
CONCLUSION.This analysis of durotomy-associated closed malpractice claims after spine surgery is the largest yet conducted. Durotomy cannot always be considered an entirely benign event, and these findings have several direct implications for clinicianslate-presenting or dehiscent durotomy may be associated with adverse outcomes and subsequent risk of litigation, timely reoperation in the event of durotomy-related complications may not increase surgeon liability, and spine surgeons should be prepared to defend their choice of durotomy repair technique, should dehiscence occur.Level of Evidence3
•Different segmentation pipelines may provide inconsistent quantification of brain structures.•The intra- and inter-method agreement between two popular segmentation software packages SPM12 and ...FreeSurfer v6.0.•SPM provides more consistent results both in the intra- and the inter-method agreement evaluation.•There are consistent biases in the estimates of gray matter and white matter between SPM and FreeSurfer.•To cross-validate the findings of each study against different segmentation methods before interpreting of the results.
The lack of inter-method agreement can produce inconsistent results in neuroimaging studies. We evaluated the intra-method repeatability and the inter-method reproducibility of two widely-used automatic segmentation methods for brain MRI: the FreeSurfer (FS) and the Statistical Parametric Mapping (SPM) software packages.
We segmented the gray matter (GM), the white matter (WM) and subcortical structures in test-retest MRI data of healthy volunteers from Kirby-21 and OASIS datasets. We used Pearson’s correlation (r), Bland-Altman plot and Dice index to study intra-method repeatability and inter-method reproducibility. In order to test whether different processing methods affect the results of a neuroimaging-based group study, we carried out a statistical comparison between male and female volume measures.
A high correlation was found between test-retest volume measures for both SPM (r in the 0.98–0.99 range) and FS (r in the 0.95–0.99 range). A non-null bias between test-retest FS volumes was detected for GM and WM in the OASIS dataset. The inter-method reproducibility analysis measured volume correlation values in the 0.72–0.98 range and the overlap between the segmented structures assessed by the Dice index was in the 0.76–0.83 range. SPM systematically provided significantly greater GM volumes and lower WM and subcortical volumes with respect to FS. In the male vs. female brain volume comparisons, inconsistencies arose for the OASIS dataset, where the gender-related differences appear subtler with respect to the Kirby dataset.
The inter-method reproducibility should be evaluated before interpreting the results of neuroimaging studies.
Several complex organic molecules are routinely detected in high abundances towards hot cores and hot corinos. For many of them, their paths of formation in space are uncertain, as gas-phase ...reactions alone seem to be insufficient.
In this paper, we investigate a possible solid-phase route of formation for methyl formate (HCOOCH3). We use a chemical model updated with recent results from an experiment where simulated grain surfaces were irradiated with 200-keV protons at 16 K, to simulate the effects of cosmic ray irradiation on grain surfaces.
We find that this model may be sufficient to reproduce the observed methyl formate in dark clouds, but not that found in hot cores and corinos.
•We present UV spectra obtained after ion (S and Ar) implantation in frozen gases (H2O, O2, CO2)•Sulfur dioxide is not detectable after sulfur implantation.•Ozone is formed after argon and sulfur ion ...implantation.•An absorption band on Ganymede is well fitted•Ion implantation produces an UV spectral reddening
We present new experimental results relative to 144 keV S9+ or Ar9+ ion implantation in targets made of oxygen rich frozen gases (O2, CO2) and mixtures with water ice. Spectra in the UV (200–400 nm) range have been obtained before and after implantation. The targets have been selected because they can be representative of the parent molecules from which SO2 and O3, observed to be present on the surfaces of Jupiter’s icy Moons, could be formed due to radiolysis induced by the abundant magnetospheric ions.
The results indicate that sulfur dioxide is not detectable after sulfur implantation in oxygen bearing species. Ozone is formed after argon and sulfur ion implantation. Sulfur implantation in O2 and CO2 targets also induces the formation of a band centered at about 255 nm (that we tentatively attribute to SO3− radicals). In the mixtures with water the band appears initially at the same wavelength and shifts to about 247 nm at higher ion fluences possibly indicating the formation of sulfite (HSO3−) ions. An absorption band observed on Ganymede is well fitted by using three components: ozone, sulfite ions and a not identified component having an absorption band centered at 298 nm.
In all of the studied cases ion implantation produces a spectral reddening over the investigated spectral range (200–400 nm) that well mimics the observed spectral slopes of Jupiter’s icy satellites.
Context. Several molecular species have been observed as frozen gases in cold environments such as grains in the interstellar/circumstellar medium or icy objects in the outer solar system. Because N2 ...and O2 are homonuclear, symmetric molecules are not easily observed. It is therefore relevant to find indirect methods to prove their presence from astronomical observations. Aims. Here we investigate one of the possible indirect methods, namely the formation of specific molecules by cosmic ion bombardment of ices in astrophysical environments that contain O2 and N2. The observation of these molecules in astronomical environments could act as a trojan horse to detect the presence of frozen molecular oxygen and/or nitrogen. Methods. We have conducted ion bombardment experiments of frozen O2, H2O and their mixtures with N2 at the laboratories of CIMAP-GANIL at Caen (France) and LASp at Catania (Italy). Different ions (13C2+, Ar2+ and H+) and energies (30–200 keV) have been used. Results. We have found that 13CO2 is formed when carbon ions are implanted in ices containing H2O and/or O2. Ozone and nitrogen oxides (NO, N2O, NO2) are formed in the studied ices containing O2 and N2 with different relative abundances. Conclusions. We suggest that ozone and nitrogen oxides are present and have to be searched for in some specific environments such as dense clouds in the interstellar medium and the surfaces of Pluto, Charon and Triton. Their observation could demonstrate the presence of molecular oxygen and/or nitrogen. A possible interest for the observations of atmospheres in exo-planetary objects is also discussed.
Treatment in medical oncology is gradually shifting from the use of nonspecific chemotherapeutic agents toward an era of novel targeted therapy in which drugs and their combinations target specific ...aspects of the biology of tumor cells. Multiple myeloma (MM) has become one of the best examples in this regard, reflected in the identification of new pathogenic mechanisms, together with the development of novel drugs that are being explored from the preclinical setting to the early phases of clinical development. We review the biological rationale for the use of the most important new agents for treating MM and summarize their clinical activity in an increasingly busy field. First, we discuss data from already approved and active agents (including second- and third-generation proteasome inhibitors (PIs), immunomodulatory agents and alkylators). Next, we focus on agents with novel mechanisms of action, such as monoclonal antibodies (MoAbs), cell cycle-specific drugs, deacetylase inhibitors, agents acting on the unfolded protein response, signaling transduction pathway inhibitors and kinase inhibitors. Among this plethora of new agents or mechanisms, some are specially promising: anti-CD38 MoAb, such as daratumumab, are the first antibodies with clinical activity as single agents in MM. Moreover, the kinesin spindle protein inhibitor Arry-520 is effective in monotherapy as well as in combination with dexamethasone in heavily pretreated patients. Immunotherapy against MM is also being explored, and probably the most attractive example of this approach is the combination of the anti-CS1 MoAb elotuzumab with lenalidomide and dexamethasone, which has produced exciting results in the relapsed/refractory setting.
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