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Advances in computer science and bioinspired robotics are ushering machines out of the lab.

To fully realize the potential of robots in society, we need to mature the debate on robotic labor.

A move toward active tactile sensing is required to enable robots to better figure out the world on their own.

Robots are at the frontier of space and deep-sea exploration; they will continue to lead our search into the unknown.

Background Endogenous fibrinolytic activation contributes to coagulopathy and mortality after trauma. Administering tranexamic acid (TXA), an antifibrinolytic agent, is one strategy to reduce bleeding; however, it must be given soon after injury to be effective and minimize adverse effects. Administering TXA topically to a wound site would decrease the time to treatment and could enable both local and systemic delivery if a suitable formulation existed to deliver the drug deep into wounds adequately. Objectives To determine whether self-propelling particles could increase the efficacy of TXA. Methods Using previously developed self-propelling particles, which consist of calcium carbonate and generate CO2 gas, TXA was formulated to disperse in blood and wounds. The antifibrinolytic properties were assessed in vitro and in a murine tail bleeding assay. Self-propelled TXA was also tested in a swine model of junctional hemorrhage consisting of femoral arteriotomy without compression. Results Self-propelled TXA was more effective than non-propelled formulations in stabilizing clots from lysis in vitro and reducing blood loss in mice. It was well tolerated when administered subcutaneously in mice up to 300 to 1000 mg/kg. When it was incorporated in gauze, four of six pigs treated after a femoral arteriotomy and without compression survived, and systemic concentrations of TXA reached approximately 6 mg/L within the first hour. Conclusions A formulation of TXA that disperses the drug in blood and wounds was effective in several models. It may have several advantages, including supporting local clot stabilization, reducing blood loss from wounds, and providing systemic delivery of TXA. This approach could both improve and simplify prehospital trauma care for penetrating injury.

Background Approximately half of cutaneous melanoma tissues harbor BRAF V600E mutations, resulting in a constitutive activation of the mitogen-activated protein kinase (MAPK) pathway. Nuclear-cytoplasmic transport machinery is dysregulated in neoplastic cells and alters the key regulatory proteins that can lead to tumor progression and drug resistance. The significance of nuclear localization of BRAF V600E has not been fully understood. We examined the clinical significance of intracellular localization of BRAF V600E in cutaneous melanoma. Study Design Immunohistochemical analysis of BRAF V600E was performed on formalin-fixed, paraffin-embedded specimens of cutaneous melanoma (n = 91). Staining intensity was graded in a blinded manner. Correlations to clinical factors were analyzed by Fisher's exact test and 2-tailed t -test. Localization of BRAF V600E was determined in melanoma cells, and we investigated their resistance to BRAF V600E -specific inhibitor according to nuclear localization in both in vitro and in vivo models. Results We included 91 patients, of whom 32% (29 of 91) had cytoplasmic BRAF V600E . Nuclear BRAF V600E was observed in 30% (27 of 91). Overall, BRAF V600E expression correlated with TNM stage (p = 0.011), mitotic activity (p = 0.010), and ulceration (p = 0.045). Nuclear BRAF V600E expression correlated with overall clinical stage (p BRAF V600E was identified in the nucleus, and its translocation was serum dependent. Our in vitro and in vivo data revealed sequestration of BRAF V600E in the cytosol-sensitized resistant cells to vemurafenib; nuclear retention of BRAF V600E was associated with aggressiveness and drug resistance. Conclusions Nuclear localization of BRAF V600E is associated with melanoma aggressiveness. Further multi-institutional studies are warranted to confirm the clinical relevance of nuclear localization of BRAF V600E .

Artificial Intelligence The Olympic sport of curling is played on an ice sheet that is prone to changes throughout a match. The uncertain conditions of the ice sheet add further complexity to the game, beyond the prerequisites of accurate throwing and strategic thinking, making it a difficult sport to master and a challenging problem to solve for roboticists. Won et al. developed a curling robot, which they called Curly, that uses an adaptive deep reinforcement learning framework to react to past errors and adapt its throws to the current ice sheet conditions. Curly demonstrated human-like performance by winning three out of four matches against top-ranked human curling teams. Sci. Robot. 5 , eabb9764 (2020).

Microrobots Batteries are a convenient source of energy for untethered miniature robots. However, the low specific energy of small-scale batteries sets limits on how long such a robot can operate. Yang et al. report an insect-scale robot called RoBeetle that is powered by the controlled catalytic combustion of methanol, a fuel with more than 10 times the specific energy of a small-scale battery. RoBeetle, with size and mass comparable to a small insect, can carry payloads of up to 2.6 times its body weight, crawl on rough surfaces, and ascend inclines of 15 degrees. Sci. Robot. 5 , eaba0015 (2020).

Space Robots Traversing over regolith—a loose, granular soil that covers large swathes of Mars and the Moon—is challenging for wheeled planetary rovers because it can cause wheel locking. Using a laboratory model of NASA's Resource Prospector 15, Shrivastava et al. developed a scaled-down robot rover called Mini Rover that combines wheel spinning with a cyclic-legged gait to ascend steep, granular terrain. Mini Rover uses its wheels to agitate the granular soil to create a stable, dynamic surface for the rover to climb using its specialized gait. Sci. Robot. 5 , aba3499 (2020).

Approximately half of cutaneous melanoma tissues harbor BRAFImmunohistochemical analysis of BRAFWe included 91 patients, of whom 32% (29 of 91) had cytoplasmic BRAFNuclear localization of BRAF

In order to improve the understanding of laser interactions of materials with homogeneous nano-structures, pulsed laser induced plasma from a low density, high-porosity multiwall carbon nanotube (CNT) sponge and a dense graphite block have been investigated by combinational spectroscopy approaches. We observe distinct differences in the laser-induced light emission of the CNT sponge and graphite block which we attribute to the occurrence of a phase explosion caused by the lower thermal conductivity and weaker mechanical strength of the CNT sponge. Furthermore, spectroscopy plasma analysis reveals that differences in the surface of the two systems play a key role in the generation of negative carbon ions. We observe a more effective production of negative ions for the CNT sponge as compared to the graphite block due to the greater number of surface defects of the CNT sponge.

Solution-processed organometal trihalide perovskite solar cells are attracting increasing interest, leading to high performances over 15% in thin film architectures. Here, we probe the presence of sub gap states in both solid and mesosuperstructured perovskite films and determine that they strongly influence the photoconductivity response and splitting of the quasi-Fermi levels in films and solar cells. We find that while the planar perovskite films are superior to the mesosuperstructured films in terms of charge carrier mobility (in excess of 20 cm(2) V(-1) s(-1)) and emissivity, the planar heterojunction solar cells are limited in photovoltage by the presence of sub gap states and low intrinsic doping densities.

Polystyrene spheres are used to template TiO2 with a single layer of 300 nm wells which are infilled with PbS quantum dots to form a heterojunction solar cell. The porous well device has an efficiency of 5.7% while the simple planar junction is limited to 3.2%. Using a combination of optical absorption and photocurrent transient decay measurement we determined that the performance enhancement comes from a combination of enhanced optical absorption and increased carrier lifetime.

Excitonic solar cells, within which bound electron-hole pairs have a central role in energy harvesting, have represented a hot field of research over the last two decades due to the compelling prospect of low-cost solar energy. However, in such cells, exciton dissociation and charge collection occur with significant losses in energy, essentially due to poor charge screening. Organic-inorganic perovskites show promise for overcoming such limitations. Here, we use optical spectroscopy to estimate the exciton binding energy in the mixed-halide crystal to be in the range of 50 meV. We show that such a value is consistent with almost full ionization of the exciton population under photovoltaic cell operating conditions. However, increasing the total photoexcitation density, excitonic species become dominant, widening the perspective of this material for a host of optoelectronic applications.

We report the low-frequency resonant Raman spectrum of methylammonium lead-iodide, a prototypical perovskite for solar cells applications, on mesoporous Al2O3. The measured spectrum assignment is assisted by DFT simulations of the Raman spectra of suitable periodic and model systems. The bands at 62 and 94 cm-1 are assigned respectively to the bending and to the stretching of the Pb-I bonds, and are thus diagnostic modes of the inorganic cage. We also assign the librations of the organic cations at 119 and 154 cm-1. The broad, unstructured 200-400 cm-1 features are assigned to the torsional mode of the methylammonium cations, which we propose as a marker of the orientational disorder of the material. Our study provides the basis to interpret the Raman spectra of organohalide perovskites, which may allow one to further understand the properties of this important class of materials in relation to their full exploitation in solar cells. © 2013 American Chemical Society.

The power-conversion efficiency of solid-state dye-sensitized solar cells can be optimized by reducing the energy offset between the highest occupied molecular orbital (HOMO) levels of dye and hole-transporting material (HTM) to minimize the loss-in-potential. Here, we report a study of three novel HTMs with HOMO levels slightly above and below the one of the commonly used HTM 2,2′,7,7′- tetrakis(N,N-di-p-methoxyphenylamino)-9,9′- spirobifluorene (spiro-OMeTAD) to systematically explore this possibility. Using transient absorption spectroscopy and employing the ruthenium based dye Z907 as sensitizer, it is shown that, despite one new HTM showing a 100% hole-transfer yield, all devices based on the new HTMs performed worse than those incorporating spiro-OMeTAD. We further demonstrate that the design of the HTM has an additional impact on the electronic density of states present at the TiO2 electrode surface and hence influences not only hole- but also electron-transfer from the sensitizer. These results provide insight into the complex influence of the HTM on charge transfer and provide guidance for the molecular design of new materials. © 2013 American Chemical Society.

The power conversion efficiency of hybrid solid-state solar cells has more than doubled from 7 to 15% over the past year. This is largely as a result of the incorporation of organometallic trihalide perovskite absorbers into these devices. But, as promising as this development is, long-term operational stability is just as important as initial conversion efficiency when it comes to the development of practical solid-state solar cells. Here we identify a critical instability in mesoporous TiO₂-sensitized solar cells arising from light-induced desorption of surface-adsorbed oxygen. We show that this instability does not arise in mesoporous TiO₂-free mesosuperstructured solar cells. Moreover, our TiO₂-free cells deliver stable photocurrent for over 1,000 h continuous exposure and operation under full spectrum simulated sunlight.

The power conversion efficiency of hybrid solid-state solar cells has more than doubled from 7 to 15% over the past year. This is largely as a result of the incorporation of organometallic trihalide perovskite absorbers into these devices. But, as promising as this development is, long-term operational stability is just as important as initial conversion efficiency when it comes to the development of practical solid-state solar cells. Here we identify a critical instability in mesoporous TiO₂-sensitized solar cells arising from light-induced desorption of surface-adsorbed oxygen. We show that this instability does not arise in mesoporous TiO₂-free mesosuperstructured solar cells. Moreover, our TiO₂-free cells deliver stable photocurrent for over 1,000 h continuous exposure and operation under full spectrum simulated sunlight.

This thesis details the development of a novel photovoltaic device based on organometal halide perovskites. The initial focus of this thesis begins with the study of lighttrapping strategies in solid-state dye-sensitised solar cells (detailed in chapter 3). While I report enhancement in device performance through the application of near and far-field light-trapping techniques, I find that improvements remain step-wise due to fundamental limitations currently employed in dye-sensitised solar cell technology— notably, the available light-sensitising materials. I found a promising yet under researched family of materials in the methyl ammonium tri-halide plumbate perovskite (detailed in chapter 4). The perovskite light-sensitiser was applied to the traditional mesoscopic sensitised solar cell device architecture as a replacement to conventional dye yielding world-record breaking photo-conversion e!ciencies for solid-state sensitised solar cells as high as 8.5%. The system was further developed leading to the conception of a novel device architecture, termed the mesoporous superstructured solar cell (MSSC), this new architecture replaces the conventional mesoporous titanium dioxide semiconductor with a porous insulating oxide in aluminium oxide, resulting in very low fundamental losses evidenced through high photo-generated open-circuit voltages of over 1.1 V. This development has delivered striking photo-conversion ef- ficiencies of 10.9% (detailed in chapter 6).

Perovskite Photovoltaics For many types of low-cost solar cells, including those using dye-sensitized titania, performance is limited by low open-circuit voltages. Lee et al. (p. 643 , published online 4 October; see the Perspective by Norris and Aydil ) have developed a solid-state cell in which structured films of titania or alumina nanoparticles are solution coated with a lead-halide perovskite layer that acts as the absorber and n-type photoactive layer. These particles are coated with a spirobifluorene organic-hole conductor in a solar cell with transparent oxide and metal contacts. For the alumina particles, power conversion efficiencies of up to 10.9% were obtained.

We present an investigation into incorporating core-shell Au-SiO 2 nanoparticles into dye-sensitized solar cells. We demonstrate plasmon-enhanced light absorption, photocurrent, and efficiency for both iodide/triiodide electrolyte based and solid-state dye-sensitized solar cells. Our spectroscopic investigation indicates that plasmon-enhanced photocarrier generation competes well with plasmons oscillation damping with in the first tens of femtoseconds following light absorption. © 2010 American Chemical Society.

Emerging many-core chip multiprocessors will integrate dozens of small processing cores with an on-chip interconnect consisting of point-to-point links. The interconnect enables the processing cores to not only communicate, but to share common resources such as main memory resources and I/O controllers. In this work, we propose an arbitration scheme to enable equality of service (EoS) in access to a chip’s shared resources. That is, we seek to remove any bias in a core’s access to a shared resource based on its location in the CMP. We propose using probabilistic arbitration combined with distance-based weights to achieve EoS and overcome the limitation of conventional round-robin arbiter. We describe how nonlinear weights need to be used with probabilistic arbiters and propose three different arbitration weight metrics – fixed weight, constantly increasing weight, and variably increasing weight. By only modifying the arbitration of an on-chip router, we do not require any additional buffers or virtual channels and create a simple, low-cost mechanism for achieving EoS. We evaluate our arbitration scheme across a wide range of traffic patterns. In addition to providing EoS, the proposed arbitration has additional benefits which include providing quality-of-service features (such as differentiated service) and providing fairness in terms of both throughput and latency that approaches the global fairness achieved with age-base arbitration – thus, providing a more stable network by achieving high sustained throughput beyond saturation.

The on-chip network of emerging many-core CMPs enables the sharing of numerous on-chip components. This on-chip network needs to ensure fairness when accessing the shared resources. In this work, we propose providing equality of service (EoS) in future many-core CMPs on-chip networks by leveraging distance, or hop count, to approximate the age of packets in the network. We propose probabilistic arbitration combined with distance-based weights to achieve EoS and overcome the limitation of conventional round-robin arbiter. We describe how nonlinear weights need to be used with probabilistic arbiters and propose three different arbitration weight metrics - fixed weight, constantly increasing weight, and variably increasing weight. By only modifying the arbitration of an on-chip router, we do not require any additional buffers or virtual channels and create a complexity-effective mechanism for achieving EoS.

A body has a first portion whose exterior surface is similar to that of a corresponding, first portion of a portable media device. An acoustic aperture is formed at a location that is similar to that of a built-in earpiece, speaker, or microphone aperture in the media device. An acoustic port is formed in the exterior surface of the body, and is adapted to be coupled to a sound test tool. An internal cavity acoustically couples the acoustic port to the acoustic aperture. Other embodiments are also described and claimed.

We have reduced the processing temperature of the bulk absorber layer in CH3NH3PbI3-xClx perovskite solar cells from 500 to

Some embodiments of the present invention provide a system which supports a dual-purpose aperture for an electronic device. This system includes a first component configured to perform an acoustic function through the aperture and a second component configured to perform a non-acoustic function through the aperture.