Graphene and other two-dimensional materials, such as transition metal dichalcogenides, have rapidly established themselves as intriguing building blocks for optoelectronic applications, with a ...strong focus on various photodetection platforms. The versatility of these material systems enables their application in areas including ultrafast and ultrasensitive detection of light in the ultraviolet, visible, infrared and terahertz frequency ranges. These detectors can be integrated with other photonic components based on the same material, as well as with silicon photonic and electronic technologies. Here, we provide an overview and evaluation of state-of-the-art photodetectors based on graphene, other two-dimensional materials, and hybrid systems based on the combination of different two-dimensional crystals or of two-dimensional crystals and other (nano)materials, such as plasmonic nanoparticles, semiconductors, quantum dots, or their integration with (silicon) waveguides.
Epidermal growth factor receptor (EGFR) inhibitors are valuable therapeutics in metastatic colorectal cancer (mCRC). Anti-EGFR monoclonal antibodies (MoAbs), such as cetuximab or panitumumab, in ...combination with chemotherapy are effective treatment options for patients with RAS and BRAF wild-type mCRC. Nevertheless, several issues are still open concerning the optimal use of anti-EGFR drugs in the continuum of care of mCRC. Novel approaches for increasing the efficacy of anti-EGFR therapies include better molecular selection of EGFR-dependent mCRC, intensification of chemotherapy, combination of anti-EGFR MoAbs and immune checkpoint inhibitors, and reintroduction of EGFR blockade or ‘rechallenge’ in selected patients who have previously responded to anti-EGFR MoAb therapy. An extensive translational research program was conducted in the Cetuximab After Progression in KRAS wIld-type colorectal cancer patients-Gruppo Oncologico dell' Italia Meridionale (CAPRI-GOIM) study with the aims of determining which subgroups of patients could benefit from the continuous inhibition of EGFR, from evaluating the role of liquid biopsy-based and its concordance with tissue-based molecular testing, and from investigating novel potential mechanisms of resistance to anti-EGFR therapies. In this review, we summarize the translational and clinical findings of the CAPRI-GOIM program in the context of the current knowledge of therapeutic strategies and of ongoing research on more appropriate uses of anti-EGFR therapies in RAS and BRAF wild-type mCRC patients.
•The epidermal growth factor (EGFR) is a therapeutic option for patients with all RAS WT metastatic colorectal cancer (mCRC).•A better knowledge of the mechanism of primary or acquired resistance to EGFR-therapies can improve patient's selection.•Despite disease progression a subset of mCRC are still sensitive to EGFR inhibition.•Rechallenge strategies with anti-EGFR might represent a promising therapeutic option.
Science and technologies based on terahertz frequency electromagnetic radiation (100 GHz-30 THz) have developed rapidly over the last 30 years. For most of the 20th Century, terahertz radiation, then ...referred to as sub-millimeter wave or far-infrared radiation, was mainly utilized by astronomers and some spectroscopists. Following the development of laser based terahertz time-domain spectroscopy in the 1980s and 1990s the field of THz science and technology expanded rapidly, to the extent that it now touches many areas from fundamental science to 'real world' applications. For example THz radiation is being used to optimize materials for new solar cells, and may also be a key technology for the next generation of airport security scanners. While the field was emerging it was possible to keep track of all new developments, however now the field has grown so much that it is increasingly difficult to follow the diverse range of new discoveries and applications that are appearing. At this point in time, when the field of THz science and technology is moving from an emerging to a more established and interdisciplinary field, it is apt to present a roadmap to help identify the breadth and future directions of the field. The aim of this roadmap is to present a snapshot of the present state of THz science and technology in 2017, and provide an opinion on the challenges and opportunities that the future holds. To be able to achieve this aim, we have invited a group of international experts to write 18 sections that cover most of the key areas of THz science and technology. We hope that The 2017 Roadmap on THz science and technology will prove to be a useful resource by providing a wide ranging introduction to the capabilities of THz radiation for those outside or just entering the field as well as providing perspective and breadth for those who are well established. We also feel that this review should serve as a useful guide for government and funding agencies.
Background and Aim
The International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO), being a Federation of 62 national societies, is the ideal network to monitor the number and ...type of procedures at a global level. The IFSO survey, enriched with a special section on revisional procedures, aims to report the number and types of bariatric procedures performed worldwide in 2016 and analyzes the surgical trends from 2008 to 2016.
Methods
The 2016 IFSO Survey form was emailed to all IFSO societies. Each Society was requested to indicate the number and type of bariatric procedures performed in the country. Trend analyses from 2008 to 2016 were also performed.
Results
The total number of bariatric/metabolic procedures performed in 2016 was 685,874; 634,897 (92.6%) of which were primary and 50,977 were revisional (7.4%). Among the primary interventions, 609,897 (96%) were surgical and 25,359 (4%) were endoluminal. The most performed primary surgical bariatric/metabolic procedure was sleeve gastrectomy (SG) (
N
= 340,550; 53.6%), followed by Roux-en-Y gastric bypass (
N
= 191,326; 30.1%), and one-anastomosis gastric bypass (
N
= 30,563; 4.8%).
Conclusions
In 2016, there was an increase in the total number both of surgical and endoluminal bariatric/metabolic procedures. Revisional procedures represent about 7% of the total bariatric interventions. SG remains the most performed surgical procedure in the world.
Background and aim
Several bariatric surgery worldwide surveys have been previously published to illustrate the evolution of bariatric surgery in the last decades. The aim of this survey is to report ...an updated overview of all bariatric procedures performed in 2014.For the first time, a special section on endoluminal techniques was added.
Methods
The 2014 International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO) survey form evaluating the number and the type of surgical and endoluminal bariatric procedures was emailed to all IFSO societies. Trend analyses from 2011 to 2014 were also performed.
Results
There were 56/60 (93.3%) responders. The total number of bariatric/metabolic procedures performed in 2014 consisted of 579,517 (97.6%) surgical operations and 14,725 (2.4%) endoluminal procedures. The most commonly performed procedure in the world was sleeve gastrectomy (SG) that reached 45.9%, followed by Roux-en-Y gastric bypass (RYGB) (39.6%), and adjustable gastric banding (AGB) (7.4%). The annual percentage changes from 2013 revealed the increase of SG and decrease of RYGB in all the IFSO regions (USA/Canada, Europe, and Asia/Pacific) with the exception of Latin/South America, where SG decreased and RYGB represented the most frequent procedure.
Conclusions
There was a further increase in the total number of bariatric/metabolic procedures in 2014 and SG is currently the most frequent surgical procedure in the world. This is the first survey that describes the endoluminal procedures, but the accuracy of provided data should be hopefully improved in the next future. We encourage the creation of further national registries and their continuous updates taking into account all new bariatric procedures including the endoscopic procedures that will obtain increasing importance in the near future.
In a cluster-randomized trial involving resident physicians working in pediatric ICUs, resident physicians were randomly assigned to schedules that included shifts of 24 hours or more or to schedules ...with shifts of 16 hours or less. Contrary to the authors’ hypothesis, resident physicians made fewer serious medical errors when they followed the extended schedule.
Optical frequency comb synthesizers have represented a revolutionary approach to frequency metrology, providing a grid of frequency references for any laser emitting within their spectral coverage. ...Extending the metrological features of optical frequency comb synthesizers to the terahertz domain would be a major breakthrough, due to the widespread range of accessible strategic applications and the availability of stable, high-power and widely tunable sources such as quantum cascade lasers. Here we demonstrate phase-locking of a 2.5 THz quantum cascade laser to a free-space comb, generated in a LiNbO(3) waveguide and covering the 0.1-6 THz frequency range. We show that even a small fraction (<100 nW) of the radiation emitted from the quantum cascade laser is sufficient to generate a beat note suitable for phase-locking to the comb, paving the way to novel metrological-grade terahertz applications, including high-resolution spectroscopy, manipulation of cold molecules, astronomy and telecommunications.
Miniaturized frequency comb sources across hard-to-access spectral regions, i.e. mid- and far-infrared, have long been sought. Four-wave-mixing based Quantum Cascade Laser combs (QCL-combs) are ideal ...candidates, in this respect, due to the unique possibility to tailor their spectral emission by proper nanoscale design of the quantum wells. We demonstrate full-phase-stabilization of a QCL-comb against the primary frequency standard, proving independent and simultaneous control of the two comb degrees of freedom (modes spacing and frequency offset) at a metrological level. Each emitted mode exhibits a sub-Hz relative frequency stability, while a correlation analysis on the modal phases confirms the high degree of coherence in the device emission, over different power-cycles and over different days. The achievement of fully controlled, phase-stabilized QCL-comb emitters proves that this technology is mature for metrological-grade uses, as well as for an increasing number of scientific and technological applications.
We report a metrological-grade THz spectroscopy based on the combination of a THz frequency-comb synthesizer (FCS) and a THz quantum cascade laser (QCL). The QCL, emitting at 2.5 THz, is phase locked ...to the free-space THz FCS, and its frequency is swept across a methanol transition by tuning the comb-repetition rate, which is ultimately disciplined by the Cs primary frequency standard. The absolute frequency scale provides an uncertainty of a few parts in 10−11 on the laser frequency and 10−9 on the line-center determination, ranking this technique among the most precise ever developed in the THz range.
Full text
Available for:
CMK, CTK, FMFMET, NUK, UL
PDF
