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A durable molecular catalyst for water oxidation has been made from readily available and relatively inexpensive materials. Roughly three-fourths of the power generated globally comes from burning fossil fuels. For solar energy to compete directly as a replacement, technologies are needed to capture this energy in a chemical form—as a fuel—so it can be used when sunlight is not available. One bottleneck in the development of practical solar fuels is the water oxidation reaction. Water is the only potential source of electrons capable of reducing protons to H 2 or CO 2 to carbonaceous fuels on a global scale. Thus, while there may be many options for reduction catalysts, redox cycling inevitably requires the coupling of reduction reactions to water oxidation (see the figure, panel A). On page 342 of this issue, Yin et al. ( 1 ) report on a water-soluble water oxidation catalyst that has a reaction center containing four cobalt (Co) atoms. Its surrounding ligands are not organic groups but are polyoxotungstate (PW 9 O 34 9− ) anions that resemble the solid oxide supports of heterogeneous catalysts. This catalyst weds the best features of extant heterogeneous and homogeneous catalysts while remedying many of their respective disadvantages.

Radiation therapy (RT) continues to play an important role in the treatment of cancer. Adaptive RT (ART) is a novel method through which RT treatments are evolving. With the ART approach, computed tomography or magnetic resonance (MR) images are obtained as part of the treatment delivery process. This enables the adaptation of the irradiated volume to account for changes in organ and/or tumor position, movement, size, or shape that may occur over the course of treatment. The advantages and challenges of ART maybe somewhat abstract to oncologists and clinicians outside of the specialty of radiation oncology. ART is positioned to affect many different types of cancer. There is a wide spectrum of hypothesized benefits, from small toxicity improvements to meaningful gains in overall survival. The use and application of this novel technology should be understood by the oncologic community at large, such that it can be appropriately contextualized within the landscape of cancer therapies. Likewise, the need to test these advances is pressing. MR-guided ART (MRgART) is an emerging, extended modality of ART that expands upon and further advances the capabilities of ART. MRgART presents unique opportunities to iteratively improve adaptive image guidance. However, although the MRgART adaptive process advances ART to previously unattained levels, it can be more expensive, time-consuming, and complex. In this review, the authors present an overview for clinicians describing the process of ART and specifically MRgART.

Orbital and surface observations can shed light on the internal structure of Mars. NASA’s InSight mission allows mapping the shallow subsurface of Elysium Planitia using seismic data. In this work, we apply a classical seismological technique of inverting Rayleigh wave ellipticity curves extracted from ambient seismic vibrations to resolve, for the first time on Mars, the shallow subsurface to around 200 m depth. While our seismic velocity model is largely consistent with the expected layered subsurface consisting of a thin regolith layer above stacks of lava flows, we find a seismic low-velocity zone at about 30 to 75 m depth that we interpret as a sedimentary layer sandwiched somewhere within the underlying Hesperian and Amazonian aged basalt layers. A prominent amplitude peak observed in the seismic data at 2.4 Hz is interpreted as an Airy phase related to surface wave energy trapped in this local low-velocity channel. We invert Rayleigh wave ellipticity curves extracted from ambient seismic vibrations at the InSight landing site to resolve, for the first time on Mars, the shallow subsurface to around 200 m depth. While our seismic velocity model is largely consistent with the expected stacks of lava flows, we find a seismic low velocity zone at about 30 to 75 m depth that we interpret as a sedimentary layer sandwiched between layers of basalt flows.

Purpose To evaluate the dosimetric and image‐guided radiation therapy (IGRT) performance of a novel generative adversarial network (GAN) generated synthetic CT (synCT) in the brain and compare its performance for clinical use including conventional brain radiotherapy, cranial stereotactic radiosurgery (SRS), planar, and volumetric IGRT. Methods and Materials SynCT images for 12 brain cancer patients (6 SRS, 6 conventional) were generated from T1‐weighted postgadolinium magnetic resonance (MR) images by applying a GAN model with a residual network (ResNet) generator and a convolutional neural network (CNN) with 5 convolutional layers as the discriminator that classified input images as real or synthetic. Following rigid registration, clinical structures and treatment plans derived from simulation CT (simCT) images were transferred to synCTs. Dose was recalculated for 15 simCT/synCT plan pairs using fixed monitor units. Two‐dimensional (2D) gamma analysis (2%/2 mm, 1%/1 mm) was performed to compare dose distributions at isocenter. Dose–volume histogram (DVH) metrics (D95%, D99%, D0.2cc, and D0.035cc) were assessed for the targets and organ at risks (OARs). IGRT performance was evaluated via volumetric registration between cone beam CT (CBCT) to synCT/simCT and planar registration between KV images to synCT/simCT digital reconstructed radiographs (DRRs). Results Average gamma passing rates at 1%/1mm and 2%/2mm were 99.0 ± 1.5% and 99.9 ± 0.2%, respectively. Excellent agreement in DVH metrics was observed (mean difference ≤0.10 ± 0.04 Gy for targets, 0.13 ± 0.04 Gy for OARs). The population averaged mean difference in CBCT‐synCT registrations were <0.2 mm and 0.1 degree different from simCT‐based registrations. The mean difference between kV‐synCT DRR and kV‐simCT DRR registrations was <0.5 mm with no statistically significant differences observed (P > 0.05). An outlier with a large resection cavity exhibited the worst‐case scenario. Conclusion Brain GAN synCTs demonstrated excellent performance for dosimetric and IGRT endpoints, offering potential use in high precision brain cancer therapy.

NASA’s InSight mission to Mars will measure seismic signals to determine the planet’s interior structure. These highly sensitive seismometers are susceptible to corruption of their measurements by environmental changes. Magnetic fields, atmosphere pressure changes, and local winds can all induce apparent changes in the seismic records that are not due to propagating ground motions. Thus, InSight carries a set of sensors called the Auxiliary Payload Sensor Suite (APSS) which includes a magnetometer, an atmospheric pressure sensor, and a pair of wind and air temperature sensors. In the case of the magnetometer, knowledge of the amplitude of the fluctuating magnetic field at the InSight lander will allow the separation of seismic signals from potentially interfering magnetic signals of either natural or spacecraft origin. To acquire such data, a triaxial fluxgate magnetometer was installed on the deck of the lander to obtain magnetic records at the same cadence as the seismometer. Similarly, a highly sensitive pressure sensor is carried by InSight to enable the removal of local ground-surface tilts due to advecting pressure perturbations. Finally, the local winds (speed and direction) and air temperature are estimated using a hot-film wind sensor with heritage from REMS on the Curiosity rover. When winds are too high, seismic signals can be ignored or discounted. Herein we describe the APSS sensor suite, the test programs for its components, and the possible additional science investigations it enables.

When reviewing agency action, the Administrative Procedure Act (APA) instructs courts to \"review the whole record or those parts of it cited by a party.\" The Supreme Court has interpreted this brief statement as a restriction on the evidentiary scope of judicial review under the APA. Courts may consider only the administrative record compiled by the agency, which includes all materials before the decisionmaker at the time he or she made the decision. The Supreme Court has recognized one exception: plaintiffs may supplement the administrative record if they make a strong showing of bad faith or improper behavior on the part of the agency. Courts consistently apply the record rule to arbitrary and capricious claims. It is less clear whether the rule applies to constitutional claims. This issue crept into two recent, high-profile Supreme Court cases—Department of Commerce v. New York and Regents of the University of California v. Department of Homeland Security—but the Court has yet to definitively resolve the issue. In the meantime, lower courts have developed three alternative approaches. This Comment argues that the record rule, though one with a robust bad faith exception, should apply to all constitutional challenges to agency action. It analyzes the APA's text, legislative history, pre- and post-APA precedent, and policy considerations to argue for a record rule approach.

Background Multiparametric MRI has shown great promise to derive multiple quantitative imaging biomarkers for treatment response assessment. Purpose To evaluate a novel deep‐learning‐enhanced MUlti‐PArametric MR sequence (DL‐MUPA) for treatment response assessment for brain metastases patients treated with stereotactic radiosurgery (SRS) and head‐and‐neck (HN) cancer patients undergoing conventionally fractionation adaptive radiation therapy. Methods DL‐MUPA derives quantitative T1 and T2 relaxation time maps from a single 4–6‐min scan denoised via DL method using least‐squares dictionary fitting. Longitudinal phantom benchmarking was performed on a NIST‐ISMRM phantom over 1 year. In patients, longitudinal DL‐MUPA data were acquired on a 1.5T MR‐simulator, including pretreatment (PreTx) and every ∼3 months after SRS (PostTx) in brain, and PreTx, mid‐treatment and 3 months PostTx in HN. Delta analysis was performed calculating changes of mean T1 and T2 values within gross tumor volumes (GTVs), residual disease (RD, HN), parotids, and submandibular glands (HN) for treatment response assessment. Uninvolved normal tissues (normal appearing white matter in brain, masseter in HN) were evaluated for within‐subject repeatability. Results Phantom benchmarking revealed excellent inter‐session repeatability (coefficient of variation < 0.9% for T1, < 6.6% for T2), suggesting reliability for longitudinal studies with systematic bias adjustment. Uninvolved normal tissue suggested acceptable within‐subject repeatability in the brain |ΔT1mean| < 36 ms (4.9%), |ΔT2mean| < 2 ms (6.1%) and HN |ΔT1mean| < 69 ms (7.0%), |ΔT2mean| < 4 ms (17.8%) with few outliers. In brain, remarkable changes were noted in a resolved metastasis (4‐month PostTx ΔT1mean = 155 ms (13.7%)) and necrotic settings (ΔT1mean = 214‐502 ms (17.6‐39.7%), ΔT2mean = 7‐41 ms (8.7‐41.4%), 6‐month to 3‐month PostTx). In HN, two base of tongue tumors exhibited T2 enhancement (PostTx GTV ΔT2mean > 7 ms (12.8%), RD ΔT2mean > 10 ms (18.1%)). A case with nodal disease resolved PostTx (GTV ΔT1mean = ‐541 ms (‐39.5%), ΔT2mean = ‐24 ms (‐32.7%), RD ΔT1mean = ‐400 ms (‐29.2%), ΔT2mean = ‐25 ms (‐35.3%)). Parotids (PostTx ΔT1mean > 82 ms (12.4%), ΔT2mean > 6 ms (13.4%)) and submandibular glands (PostTx ΔT1mean > 135 ms (14.6%), ΔT2mean > 17 ms (34.5%)) adjacent to gross disease exhibited enhancement while distant organs remained stable. Conclusions Preliminary results suggest promise of DL‐MUPA for treatment response assessment and highlight potential endpoints for functional sparing.

Purpose Rising evidence suggests that cardiac substructures are highly radiosensitive. However, they are not routinely considered in treatment planning as they are not readily visualized on treatment planning CTs (TPCTs). This work integrated the soft tissue contrast provided by low‐field MRIs acquired on an MR‐linac via image registration to further enable cardiac substructure sparing on TPCTs. Methods Sixteen upper thoracic patients treated at various breathing states (7 end‐exhalation, 7 end‐inhalation, 2 free‐breathing) on a 0.35T MR‐linac were retrospectively evaluated. A hybrid MR/CT atlas and a deep learning three‐dimensional (3D) U‐Net propagated 13 substructures to TPCTs. Radiation oncologists revised contours using registered MRIs. Clinical treatment plans were re‐optimized and evaluated for beam arrangement modifications to reduce substructure doses. Dosimetric assessment included mean and maximum (0.03cc) dose, left ventricular volume receiving 5Gy (LV‐V5), and other clinical endpoints. As metrics of plan complexity, total MU and treatment time were evaluated between approaches. Results Cardiac sparing plans reduced the mean heart dose (mean reduction 0.7 ± 0.6, range 0.1 to 2.5 Gy). Re‐optimized plans reduced left anterior descending artery (LADA) mean and LADA0.03cc (0.0–63.9% and 0.0 to 17.3 Gy, respectively). LV0.03cc was reduced by >1.5 Gy for 10 patients while 6 cases had large reductions (>7%) in LV‐V5. Left atrial mean dose was equivalent/reduced in all sparing plans (mean reduction 0.9 ± 1.2 Gy). The left main coronary artery was better spared in all cases for mean dose and D0.03cc. One patient exhibited >10 Gy reduction in D0.03cc to four substructures. There was no statistical difference in treatment time and MU, or clinical endpoints to the planning target volume, lung, esophagus, or spinal cord after re‐optimization. Four patients benefited from new beam arrangements, leading to further dose reductions. Conclusions By introducing 0.35T MRIs acquired on an MR‐linac to verify cardiac substructure segmentations for CT‐based treatment planning, an opportunity was presented for more effective sparing with limited increase in plan complexity. Validation in a larger cohort with appropriate margins offers potential to reduce radiation‐related cardiotoxicities.

Background Covid-19 has had significant effects on the quality of life of individuals around the world. Research highlights many negative impacts related to Covid-19; however, there are also potential positive impacts. The current study aimed to identify both the perceived negative and positive effects of Covid-19 among the residents of Tabriz, Iran. Materials & methods The descriptive cross-sectional study was conducted in 10 health centers in Tabriz city in 2021. Cluster random sampling was used to select the 861 study participants. A questionnaire was developed to collect demographic and Covid-19 impacts. Data were analyzed with descriptive and inferential statistics using SPSS 16 software. Results The mean (SD) of negative and positive impacts of Covid-19 was 37.7 (5.10) and 36.35 (5.31), respectively. Significant negative impacts included restriction in participation in cultural (90.4%) and religious (88.9%) activities. Positive impacts were increased attention to personal hygiene (88.7%) and attention to elders (87.6%). Gender ( p  = 0.006), work status ( p  = 0.004) and age ( p  = 0. 01) had significant association with the mean of negative impacts and work status ( p  = 0.01), age ( p  < 0.001), history of Covid-19 ( p  = 0.01) and family history of Covid-19 ( p  < 0.001) had the significant association with the mean of positive impacts of Covid-19. Conclusion The findings revealed that the general population experienced many negative impacts of Covid-19. This may be related to the priority of religious gatherings in Iranian culture. Despite the unfavorable effects of Covid-19, its positive effects and post-traumatic growth should not be ignored. Covid-19 may be used as an opportunity to develop personal growth and a positive outlook on life. Healthcare workers should reinforce the positive impacts of Covid-19 while taking into consideration the importance of spirituality among Iranian individuals during times of community lockdowns.