X-ray free-electron lasers (x-ray FELs) give us for the first time the possibility to explore structures and dynamical processes of atomic and molecular systems at the angstrom-femtosecond space and ...time scales. They generate coherent photon pulses with time duration of a few to 100 fs, peak power of 10 to 100 GW, over a wavelength range extending from about 100 nm to less than 1 A. Using these novel and unique capabilities new scientific results are being obtained in atomic and molecular sciences, in areas of physics, chemistry, and biology. This paper reviews the physical principles, the theoretical models, and the numerical codes on which x-ray FELs are based, starting from a single electron spontaneous undulator radiation to the FEL collective instability of a high density electron beam, strongly enhancing the electromagnetic radiation field intensity and its coherence properties. A short review is presented of the main experimental properties of x-ray FELs, and the results are discussed of the most recent research to improve their longitudinal coherence properties, increase the peak power, and generate multicolor spectra.
Purpose
Many apparent differences exist in aetiology, genetics, anatomy and treatment response between colon cancer (CC) and rectal cancer (RC). This study examines the differences in patient ...characteristics, prevalence of complications and their effect on short-term survival, long-term survival and the rate of recurrence between RC and CC.
Methods
For all stage II–III CC and RC patients who underwent resection with curative intent (2006–2008) in five hospitals in the Netherlands, occurrence of complications, crude survival, relative survival and recurrence rates were compared.
Results
A total of 767 CC and 272 RC patients underwent resection. Significant differences were found for age, gender, emergency surgery, T-stage and grade. CC patients experienced fewer complications compared to RC (
p
= 0.019), but CC patients had worse short-term mortality rates (1.5 versus 6.7 % for 30-day mortality,
p
= 0.001 and 5.2 versus 9.5 % for 90-day mortality,
p
= 0.032). The adjusted HR (overall survival) for CC patients with complications was 1.57 (1.23–2.01;
p
< 0.001) as compared to patients without complications; for RC, the HR was 1.79 (1.12–2.87;
p
= 0.015). Relative survival analyses showed high excess mortality in the first months after surgery and a sustained, prolonged negative effect on both CC and RC. Complications were associated with a higher recurrence rate for both CC and RC; adjusted analyses showed a trend towards a significant association.
Conclusion
Large differences exist in patient characteristics and clinical outcomes between CC and RC. CC patients have a significantly higher short-term mortality compared to RC patients due to a more severe effect of complications.
► A number of studies have demonstrated tDCS efficacy in the recovery of aphasia. ► We wonder whether tDCS can improve articulatory speech gestures in three patients. ► A persistent improvement in ...the anodic compared to the sham condition was present. ► These data are relevant for planning new interventions in aphasia rehabilitation.
A number of studies have shown that modulating cortical activity by means of transcranial direct current stimulation (tDCS) affects the performance of both healthy and brain-damaged subjects. In this study, we investigated the potential of tDCS for the recovery of apraxia of speech in 3 patients with stroke-induced aphasia. Over 2 weeks, three aphasic subjects participated in a randomized double-blinded experiment involving intensive language training for their articulatory difficulties in two tDCS conditions. Each subject participated in five consecutive daily sessions of anodic tDCS (20
min, 1
mA) and sham stimulation over the left inferior frontal gyrus (referred to as Broca's area) while they performed a repetition task. By the end of each week, a significant improvement was found in both conditions. However, all three subjects showed greater response accuracy in the anodic than in the sham condition. Moreover, results for transfer of treatment effects, although different across subjects, indicate a generalization of the recovery at the language test. Subjects 2 and 3 showed a significant improvement in oral production tasks, such as word repetition and reading, while Subjects 1 and 2 had an unexpected significant recovery in written naming and word writing under dictation tasks. At three follow-ups (1 week, 1 and 2 months after the end of treatment), response accuracy was still significantly better in the anodic than in sham condition, suggesting a long-term effect on the recovery of their articulatory gestures.
Medically-assisted procreation (MAP) has given rise to a crisis in the traditional family model, made up of a mother and a father, and led to the births of babies who are genetically and biologically ...unrelated to their legal parents. Italian legal statutes ban such practices, which are punishable by law; yet there is currently no legislation aimed at governing and regulating the legal registration of children born through such procedures abroad. Italian jurisprudence, on the other hand, has acknowledged the right to parenthood for homosexual couples, ruling that the children thus born be considered legally bound to their social parents, by virtue of the affection-based bond, rooted in harmony and listening, that has been formed within the family setting, however unconventional it may be. The paper's author feels that an intervention from lawmakers is urgent and inescapable, in order to provide targeted legislation in such a sensitive realm.
The author has delved into the most significant Italian and European court rulings related to heterologous fertilization and surrogate motherhood between 2012 and 2019, with a close focus on same-sex ...couples seeking to have their donor-conceived children born abroad legally registered in their country of origin. Undeniably, surrogacy has brought about a crisis in the traditional family model, made up of a mother and a father. The paper draws upon European Court of Human Rights established jurisprudence that upholds the children's best interests. Italian Court rulings are expounded upon as well, which have been instrumental in establishing the principles by which parental figures do not necessarily coincide with those who have generated the children (through biological bonds or delivery), but rather with those who wish to be recognized as parents. The cases herein examined involve homosexual couples who decided to travel abroad in order to gain access to surrogacy, from which children were born. In the case regarding two fathers, the child had no genetic tie with either one intended parent. The Italian Supreme Court's joint sessions have ruled that such children cannot be legally registered in Italy, since their foreign-issued birth certificates indicate no genetic connection between the children and their intended parents. The Author believes that the Supreme Court decision is valuable, but further legislative interventions will be necessary on account of scientific advancements; the issue of surrogacy is utterly complex and multi-faceted.
Trisomy 12, the third most frequent chromosomal aberration in chronic lymphocytic leukemia (CLL), confers an intermediate prognosis. In our cohort of 104 untreated patients carrying +12, NOTCH1 ...mutations occurred in 24% of cases and were associated to unmutated IGHV genes (P=0.003) and +12 as a sole cytogenetic abnormality (P=0.008). NOTCH1 mutations in +12 CLL associated with an approximately 2.4 fold increase in the risk of death, a significant shortening of survival (P<0.01) and proved to be an independent predictor of survival in multivariate analysis. Analogous to +12 CLL with TP53 disruption or del(11q), NOTCH1 mutations in +12 CLL conferred a significantly worse survival compared to that of +12 CLL with del(13q) or +12 only. The overrepresentation of cell cycle/proliferation related genes of +12 CLL with NOTCH1 mutations suggests the biological contribution of NOTCH1 mutations to determine a poor outcome. NOTCH1 mutations refine the intermediate prognosis of +12 CLL.
The time–energy information of ultrashort X-ray free-electron laser pulses generated by the Linac Coherent Light Source is measured with attosecond resolution via angular streaking of neon 1s ...photoelectrons. The X-ray pulses promote electrons from the neon core level into an ionization continuum, where they are dressed with the electric field of a circularly polarized infrared laser. This induces characteristic modulations of the resulting photoelectron energy and angular distribution. From these modulations we recover the single-shot attosecond intensity structure and chirp of arbitrary X-ray pulses based on self-amplified spontaneous emission, which have eluded direct measurement so far. We characterize individual attosecond pulses, including their instantaneous frequency, and identify double pulses with well-defined delays and spectral properties, thus paving the way for X-ray pump/X-ray probe attosecond free-electron laser science.
Dowling-Degos Disease (DDD) is a rare and disfiguring autosomal dominant genodermatosis characterized by reticulate hyperpigmented macules or follicular comedone-like papules in the intertriginous ...areas that typically presents in the third or fourth decade of life. It is a progressive disease that is often treatment-resistant. Although its association with hidradenitis suppurativa has been well described, DDD has also been less commonly reported in conjunction with other dermatologic diseases with unknown etiologic associations. Herein, we present a case of DDD with associated epidermal inclusion cysts and conduct a literature review of dermatologic conditions reported in association with DDD.
In fasted and fed states, blood insulin levels are oscillatory. While this phenomenon is well studied at high glucose levels, comparatively little is known about its origin under basal conditions. We ...propose a possible mechanism for basal insulin oscillations based on oscillations in glycolysis, demonstrated using an established mathematical model. At high glucose, this is superseded by a calcium-dependent mechanism.
The X-ray free-electron laser has opened a new era for photon science, improving the X-ray brightness by ten orders of magnitude over previously available sources. Similar to an optical laser, the ...spectral and temporal structure of the radiation pulses can be tailored to the specific needs of many experiments by accurately manipulating the lasing medium, that is, the electron beam. Here we report the generation of mJ-level two-colour hard X-ray pulses of few femtoseconds duration with an XFEL driven by twin electron bunches at the Linac Coherent Light Source. This performance represents an improvement of over an order of magnitude in peak power over state-of-the-art two-colour XFELs. The unprecedented intensity and temporal coherence of this new two-colour X-ray free-electron laser enable an entirely new set of scientific applications, ranging from X-ray pump/X-ray probe experiments to the imaging of complex biological samples with multiple wavelength anomalous dispersion.
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