An overview and a roadmap for artificial intelligence in hematology and oncology.

BACKGROUND: Artificial intelligence (AI) is influencing our society on many levels and has broad implications for the future practice of hematology and oncology. However, for many medical professionals and researchers, it often remains unclear what AI can and cannot do, and what are promising areas for a sensible application of AI in hematology and oncology. Finally, the limits and perils of using AI in oncology are not obvious to many healthcare professionals. METHODS: In this article, we provide an expert-based consensus statement by the joint Working Group on "Artificial Intelligence in Hematology and Oncology" by the German Society of Hematology and Oncology (DGHO), the German Association for Medical Informatics, Biometry and Epidemiology (GMDS), and the Special Interest Group Digital Health of the German Informatics Society (GI). We provide a conceptual framework for AI in hematology and oncology. RESULTS: First, we propose a technological definition, which we deliberately set in a narrow frame to mainly include the technical developments of the last ten years. Second, we present a taxonomy of clinically relevant AI systems, structured according to the type of clinical data they are used to analyze. Third, we show an overview of potential applications, including clinical, research, and educational environments with a focus on hematology and oncology. CONCLUSION: Thus, this article provides a point of reference for hematologists and oncologists, and at the same time sets forth a framework for the further development and clinical deployment of AI in hematology and oncology in the future.

Basal Cell Carcinoma of the Head and Neck-A Retrospective Single-Centre Comparison of the Recurrence Rate after R0 or R1 Resection.

The treatment guidelines for basal cell carcinoma (BCC) postulate complete surgical excision using microscopically controlled resection (MOHS) as the gold standard. The need to obtain a small safety margin in the complex anatomical area of the head and neck is very challenging due to the individual characteristics (localization, histology, and size) of tumors and the fact that the postoperative loss of quality of life depends on the surgical defect size. The R1 status is histopathologically defined when the safety margin is less than 1 mm even if there are no tumor cells actually infiltrating the resection margin. Therefore, some studies have already favored a watch-and-wait-strategy in R1 situations. We aimed to evaluate the outcome and recurrence rate of resected BCCs of the head and neck, especially in a histologically proven R1 situation. The outcomes of all resected BCCs observed during a 5-year period (January 2009-December 2013) in a tertiary care center were analyzed. Our standard operating procedure was microscopically controlled surgical excision with reresections until an R0 situation was achieved. In selected patients, an R1 status has been accepted after at least two resections. From the included 191 BCCs, the R1 status was accepted as the final result in 46 (24.1%) cases which had surgically clear margins and were closely followed-up. From 54 patients in the R0 and 40 patients in the R1 group who completed the follow-up (2.4 ± 0.4 years), we observed 0 and 2 local recurrences, respectively (p = 0.19). In cases where frequent follow-up can be secured and the surgical area is delicate, a surgical closure at R1 status can be justified as the recurrence rate is not significantly higher compared with R0.

Modal properties of a beam carrying OAM generated by a circular array of multiple ring-resonator emitters.

We investigate the modal properties of a beam carrying orbital angular momentum (OAM) generated by a circular array (ring) of multiple micro-ring emitters (rings) analytically and via simulation. In such a "ring-of-rings" structure, N emitters generate N optical vortex beams with the same OAM-order l0 at the same wavelength. The output beam is a coherent combination of the N vortex beams located at different azimuthal positions, having the same radial displacement. We derive an analytical expression for the output optical field and calculate the OAM-order power spectrum of the generated beam. The analytical expression and simulation results show that (1) the OAM spectrum of the output beam composes equidistant OAM spectral components, symmetrically surrounding l0 with a spacing equal to N; (2) the envelope of the OAM spectrum broadens with an increased radius of the circular array or the value of l0; and (3) the OAM components of the generated beam could be tuned either by changing the value of l0, corresponding to different spectrum envelopes, or by adding different linear phase delays to the micro-ring emitters, which does not affect the envelope of the OAM spectrum.

Demonstration of generating a 100 Gbit/s orbital-angular-momentum beam with a tunable mode order over a range of wavelengths using an integrated broadband pixel-array structure.

We experimentally generate an orbital-angular-momentum (OAM) beam with a tunable mode order over a range of wavelengths utilizing an integrated broadband pixel-array OAM emitter. The emitter is composed of a 3-to-4 coupler, four phase controllers, and a mode convertor. An optical input is split into four waveguides by the coupler. Subsequently, the four waveguide fields are coherently combined and transformed into a free-space OAM beam by the mode convertor. By tuning the phase delay Δφ between the four waveguides using the integrated phase controllers, the OAM order of the generated beam could be changed. Our results show that (a) a single OAM beam with a tunable OAM order (ℓ=-1 or ℓ=+1) is generated with the intermodal power coupling of <-11dB, and (b) in a wavelength range of 6.4 nm, a free-space link of a single 50 Gbaud quadrature-phase-shift-keying (QPSK) channel carried by the tunable OAM beam is achieved with a bit error rate below the forward-error-correction threshold. As proof of concept, a 400 Gbit/s OAM-multiplexed and WDM QPSK link is demonstrated with a ∼1-dB OSNR penalty compared with a single-beam link.

The Influence of Concentration and Temperature on the Membrane Resistance of Ion Exchange Membranes and the Levelised Cost of Hydrogen from Reverse Electrodialysis with Ammonium Bicarbonate.

The ohmic resistances of the anion and cation ion-exchange membranes (IEMs) that constitute a reverse electrodialysis system (RED) are of crucial importance for its performance. In this work, we study the influence of concentration (0.1 M, 0.5 M, 1 M and 2 M) of ammonium bicarbonate solutions on the ohmic resistances of ten commercial IEMs. We also studied the ohmic resistance at elevated temperature 313 K. Measurements have been performed with a direct two-electrode electrochemical impedance spectroscopy (EIS) method. As the ohmic resistance of the IEMs depends linearly on the membrane thickness, we measured the impedance for three different layered thicknesses, and the results were normalised. To gauge the role of the membrane resistances in the use of RED for production of hydrogen by use of waste heat, we used a thermodynamic and an economic model to study the impact of the ohmic resistance of the IEMs on hydrogen production rate, waste heat required, thermochemical conversion efficiency and the levelised cost of hydrogen. The highest performance was achieved with a stack made of FAS30 and CSO Type IEMs, producing hydrogen at 8.48× 10-7 kg mmem-2s-1 with a waste heat requirement of 344 kWh kg-1 hydrogen. This yielded an operating efficiency of 9.7% and a levelised cost of 7.80 € kgH2-1.

Utilizing phase delays of an integrated pixel-array structure to generate orbital-angular-momentum beams with tunable orders and a broad bandwidth.

We study the relationship between the input phase delays and the output mode orders when using a pixel-array structure fed by multiple single-mode waveguides for tunable orbital-angular-momentum (OAM) beam generation. As an emitter of a free-space OAM beam, the designed structure introduces a transformation function that shapes and coherently combines multiple (e.g., four) equal-amplitude inputs, with the kth input carrying a phase delay of (k-1)Δφ. The simulation results show that (1) the generated OAM order ℓ is dependent on the relative phase delay Δφ; (2) the transformation function can be tailored by engineering the structure to support different tunable ranges (e.g., l={-1},{-1,+1},{-1,0,+1}, or {-2,-1,+1,+2}); and (3) multiple independent coaxial OAM beams can be generated by simultaneously feeding the structure with multiple independent beams, such that each beam has its own Δφ value for the four inputs. Moreover, there is a trade-off between the tunable range and the mode purity, bandwidth, and crosstalk, such that the increase of the tunable range leads to (a) decreased mode purity (from 91% to 75% for l=-1), (b) decreased 3 dB bandwidth of emission efficiency (from 285 nm for l={-1} to 122 nm for l={-2,-1,+1,+2}), and (c) increased crosstalk within the C-band (from -23.7 to -13.2dB when the tunable range increases from 2 to 4).

Demonstration of using two aperture pairs combined with multiple-mode receivers and MIMO signal processing for enhanced tolerance to turbulence and misalignment in a 10 Gbit/s QPSK FSO link.

We utilize aperture diversity combined with multiple-mode receivers and multiple-input-multiple-output (MIMO) digital signal processing (DSP) to demonstrate enhanced tolerance to atmospheric turbulence and spatial misalignment in a 10 Gbit/s quadrature-phase-shift-keyed (QPSK) free-space optical (FSO) link. Turbulence and misalignment could cause power coupling from the fundamental Gaussian mode into higher-order modes. Therefore, we detect power from multiple modes and use MIMO DSP to enhance the recovery of the original data. In our approach, (a) each of multiple transmitter apertures transmits a single fundamental Gaussian beam carrying the same data stream, (b) each of multiple receiver apertures detects the signals that are coupled from the fundamental Gaussian beams to multiple orbital angular momentum (OAM) modes, and (c) MIMO DSP is used to recover the data over multiple modes and receivers. Our simulation shows that the outage probability could be reduced from >0.1 to <0.01. Moreover, we experimentally demonstrate the scheme by transmitting two fundamental Gaussian beams carrying the same data stream and recovering the signals on OAM modes 0 and +1 at each receiver aperture. We measure an up to ∼10dB power-penalty reduction for a bit error rate (BER) at the 7% forward error correction limit for a 10 Gbit/s QPSK signal.

Simultaneous turbulence mitigation and channel demultiplexing for two 100 Gbit/s orbital-angular-momentum multiplexed beams by adaptive wavefront shaping and diffusing.

We experimentally demonstrate simultaneous turbulence mitigation and channel demultiplexing in a 200 Gbit/s orbital-angular-momentum (OAM) multiplexed link by adaptive wavefront shaping and diffusing (WSD) the light beams. Different realizations of two emulated turbulence strengths (the Fried parameter ${r_0} = 0.4,\,1.0\;{\rm mm}$r0=0.4,1.0mm) are mitigated. The experimental results show the following. (1) Crosstalk between OAM $l = + 1$l=+1 and $l = - 1$l=-1 modes can be reduced by $ {\gt} {10.0}$>10.0 and $ {\gt} {5.8}\;{\rm dB}$>5.8dB, respectively, under the weaker turbulence (${r_0} = 1.0\;{\rm mm}$r0=1.0mm); crosstalk is further improved by $ {\gt} {17.7}$>17.7 and $ {\gt} {19.4}\;{\rm dB}$>19.4dB, respectively, under most realizations in the stronger turbulence (${r_0} = 0.4\;{\rm mm}$r0=0.4mm). (2) The optical signal-to-noise ratio penalties for the bit error rate performance are measured to be ${\sim}{0.7}$∼0.7 and ${\sim}{1.6}\;{\rm dB}$∼1.6dB under weaker turbulence, while measured to be ${\sim}{3.2}$∼3.2 and ${\sim}{1.8}\;{\rm dB}$∼1.8dB under stronger turbulence for OAM $l = + 1$l=+1 and $l = - 1$l=-1 mode, respectively.

Mitigation for turbulence effects in a 40-Gbit/s orbital-angular-momentum-multiplexed free-space optical link between a ground station and a retro-reflecting UAV using MIMO equalization.

We experimentally demonstrate turbulence effect mitigation in a 100-m round-trip orbital-angular-momentum (OAM)-multiplexed free-space optical communication link between a ground transmitter and a ground receiver via a retro-reflecting hovering unmanned aerial vehicle (UAV) using multiple-input-multiple-output (MIMO) equalization. In our demonstration, two OAM beams at 1550 nm are transmitted to the UAV through emulated atmospheric turbulence, each carrying a 20-Gbit/s signal. 2×2 MIMO equalization is used to mitigate turbulence-induced crosstalk between the two OAM channels. Bit error rates below the 7% overhead forward error correction limit of 3.8×10-3 are achieved for both channels.

Coherent optical wireless communication link employing orbital angular momentum multiplexing in a ballistic and diffusive scattering medium.

We experimentally investigate the scattering effect on an 80 Gbit/s orbital angular momentum (OAM) multiplexed optical wireless communication link. The power loss, mode purity, cross talk, and bit error rate performance are measured and analyzed for different OAM modes under scattering levels from ballistic to diffusive regions. Results show that (i) power loss is the main impairment in the ballistic scattering, while the mode purities of different OAM modes are not significantly affected; (ii) in the diffusive scattering, however, the performance of an OAM-multiplexed link further suffers from the increased cross talk between the different OAM modes.

Experimental demonstration of beaconless beam displacement tracking for an orbital angular momentum multiplexed free-space optical link.

In this Letter, we experimentally demonstrate beaconless beam displacement tracking for free-space optical communication link multiplexing multiple orbital angular momentum (OAM) beams, where the data-carrying OAM beams are used for position detection. 400 Gbit/s data transmission is demonstrated under emulated lateral displacement of up to ±10 mm with power penalties of less than 3 dB for all channels. Channel crosstalk is reduced by the beam tracking system to below -18 dB. Moreover, we investigate using a Gaussian beacon for beam displacement tracking, and achieve similar channel crosstalk and power penalties, compared with using the beaconless beam tracking.

High-Capacity Free-Space Optical Communications Between a Ground Transmitter and a Ground Receiver via a UAV Using Multiplexing of Multiple Orbital-Angular-Momentum Beams.

We explore the use of orbital-angular-momentum (OAM)-multiplexing to increase the capacity of free-space data transmission to moving platforms, with an added potential benefit of decreasing the probability of data intercept. Specifically, we experimentally demonstrate and characterize the performance of an OAM-multiplexed, free-space optical (FSO) communications link between a ground transmitter and a ground receiver via a moving unmanned-aerial-vehicle (UAV). We achieve a total capacity of 80 Gbit/s up to 100-m-roundtrip link by multiplexing 2 OAM beams, each carrying a 40-Gbit/s quadrature-phase-shift-keying (QPSK) signal. Moreover, we investigate for static, hovering, and moving conditions the effects of channel impairments, including: misalignments, propeller-induced airflows, power loss, intermodal crosstalk, and system bit error rate (BER). We find the following: (a) when the UAV hovers in the air, the power on the desired mode fluctuates by 2.1 dB, while the crosstalk to the other mode is -19 dB below the power on the desired mode; and (b) when the UAV moves in the air, the power fluctuation on the desired mode increases to 4.3 dB and the crosstalk to the other mode increases to -10 dB. Furthermore, the channel crosstalk decreases with an increase in OAM mode spacing.

Orbital angular momentum beams generated by passive dielectric phase masks and their performance in a communication link.

We demonstrate the generation of orbital angular momentum (OAM) beams using high-efficient polarization-insensitive phase masks. The OAM beams generated by the phase masks are characterized in terms of their tolerance to misalignment (lateral displacement or tilt) between the incident beam and phase mask. For certain scenarios, our results show that (a) when the tilt angle is within the range of -20 to +20 deg, the crosstalk among modes is less than -15 dB; and (b) lateral displacement of 0.3 mm could cause a large amount of power leaked to adjacent modes. Finally, OAM beams generated by the phase masks are demonstrated over a two-channel OAM-multiplexing link, each channel carrying a 40 Gbit/s data stream. An optical signal-to-noise-ratio (OSNR) penalty of ∼1 dB is measured without crosstalk at the bit error rate (BER) of 3.8×10-3. With crosstalk, an OSNR penalty of <1.5 dB is observed at the same BER.

Atmospheric turbulence mitigation in an OAM-based MIMO free-space optical link using spatial diversity combined with MIMO equalization.

We explore the mitigation of atmospheric turbulence effects for orbital angular momentum (OAM)-based free-space optical (FSO) communications with multiple-input multiple-output (MIMO) architecture. Such a system employs multiple spatially separated aperture elements at the transmitter/receiver, and each transmitter aperture contains multiplexed data-carrying OAM beams. We propose to use spatial diversity combined with MIMO equalization to mitigate both weak and strong turbulence distortions. In a 2×2 FSO link with each transmitter aperture containing two multiplexed OAM modes of ℓ=+1 and ℓ=+3, we experimentally show that at least two OAM data channels could be recovered under both weak and strong turbulence distortions using selection diversity assisted with MIMO equalization.

Experimental characterization of a 400 Gbit/s orbital angular momentum multiplexed free-space optical link over 120 m.

We experimentally demonstrate and characterize the performance of a 400-Gbit/s orbital angular momentum (OAM) multiplexed free-space optical link over 120 m on the roof of a building. Four OAM beams, each carrying a 100-Gbit/s quadrature-phase-shift-keyed channel are multiplexed and transmitted. We investigate the influence of channel impairments on the received power, intermodal crosstalk among channels, and system power penalties. Without laser tracking and compensation systems, the measured received power and crosstalk among OAM channels fluctuate by 4.5 dB and 5 dB, respectively, over 180 s. For a beam displacement of 2 mm that corresponds to a pointing error less than 16.7 µrad, the link bit error rates are below the forward error correction threshold of 3.8×10(-3) for all channels. Both experimental and simulation results show that power penalties increase rapidly when the displacement increases.

Free-space optical communications using orbital-angular-momentum multiplexing combined with MIMO-based spatial multiplexing.

We explore the potential of combining the advantages of multiple-input multiple-output (MIMO)-based spatial multiplexing with those of orbital angular momentum (OAM) multiplexing to increase the capacity of free-space optical (FSO) communications. We experimentally demonstrate an 80 Gbit/s FSO system with a 2×2 aperture architecture, in which each transmitter aperture contains two multiplexed data-carrying OAM modes. Inter-channel crosstalk effects are minimized by the OAM beams' inherent orthogonality and by the use of 4×4 MIMO signal processing. Our experimental results show that the bit-error rates can reach below the forward error correction limit of 3.8×10(-3) and the power penalties are less than 3.6 dB for all channels after MIMO processing. This indicates that OAM and MIMO-based spatial multiplexing could be simultaneously utilized, thereby providing the potential to enhance system performance.

Turbulence compensation of an orbital angular momentum and polarization-multiplexed link using a data-carrying beacon on a separate wavelength.

We investigate the sensing of a data-carrying Gaussian beacon on a separate wavelength as a means to provide the information necessary to compensate for the effects of atmospheric turbulence on orbital angular momentum (OAM) and polarization-multiplexed beams in a free-space optical link. The influence of the Gaussian beacon's wavelength on the compensation of the OAM beams at 1560 nm is experimentally studied. It is found that the compensation performance degrades slowly with the increase in the beacon's wavelength offset, in the 1520-1590 nm band, from the OAM beams. Using this scheme, we experimentally demonstrate a 1 Tbit/s OAM and polarization-multiplexed link through emulated dynamic turbulence with a data-carrying beacon at 1550 nm. The experimental results show that the turbulence effects on all 10 data channels, each carrying a 100 Gbit/s signal, are mitigated efficiently, and the power penalties after compensation are below 5.9 dB for all channels. The results of our work might be helpful for the future implementation of a high-capacity OAM, polarization and wavelength-multiplexed free-space optical link that is affected by atmospheric turbulence.

Decontamination and management of human remains following incidents of hazardous chemical release.

OBJECTIVE: To provide specific guidance and resources for systematic and orderly decontamination of human remains resulting from a chemical terrorist attack or accidental chemical release. DESIGN: A detailed review and health-based decision criteria protocol is summarized. Protocol basis and logic are derived from analyses of compound-specific toxicological data and chemical/physical characteristics. SETTING: Guidance is suitable for civilian or military settings where human remains potentially contaminated with hazardous chemicals may be present, such as sites of transportation accidents, terrorist operations, or medical examiner processing points. PATIENTS AND PARTICIPANTS: Guidance is developed from data-characterizing controlled experiments with laboratory animals, fabrics, and materiel. MAIN OUTCOME MEASURE(S): Logic and specific procedures for decontamination and management of remains, protection of mortuary affairs personnel, and decision criteria to determine when remains are sufficiently decontaminated are presented. RESULTS: Established procedures as well as existing materiel and available equipment for decontamination and verification provide reasonable means to mitigate chemical hazards from chemically exposed remains. Unique scenarios such as those involving supralethal concentrations of certain liquid chemical warfare agents may prove difficult to decontaminate but can be resolved in a timely manner by application of the characterized systematic approaches. Decision criteria and protocols to "clear" decontaminated remains for transport and processing are also provided. CONCLUSIONS: Once appropriate decontamination and verification have been accomplished, normal procedures for management of remains and release can be followed.