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  1. As office workers shift to telework, office building space requirements should decrease, but this relationship has not been empirically studied. We construct a dataset describing historical office building space, number of office workers, and number of teleworkers from 2003-2019 in the US, and use linear regression to estimate the effect of telework on office building space. The results show that the average office building space required for an additional office worker and teleworker is 32 and 18 square meters (340 and 191 square feet), respectively, suggesting an average 44% reduction in office building space when an office worker transitions to telework.

     
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    Free, publicly-accessible full text available April 2, 2025
  2. Free, publicly-accessible full text available June 17, 2024
  3. Recently, image-to-image translation (I2I) has met with great success in computer vision, but few works have paid attention to the geometric changes that occur during translation. The geometric changes are necessary to reduce the geometric gap between domains at the cost of breaking correspondence between translated images and original ground truth. We propose a novel geometry-aware semi-supervised method to preserve this correspondence while still allowing geometric changes. The proposed method takes a synthetic image-mask pair as input and produces a corresponding real pair. We also utilize an objective function to ensure consistent geometric movement of the image and mask through the translation. Extensive experiments illustrate that our method yields a 11.23% higher mean Intersection-Over-Union than the current methods on the downstream eye segmentation task. The generated image has a 15.9% decrease in Frechet Inception Distance indicating higher image quality. 
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  4. Abstract

    While amber suppression is the most common approach to introduce noncanonical amino acids into proteins in live cells, quadruplet codon decoding has potential to enable a greatly expanded genetic code with up to 256 new codons for protein biosynthesis. Since triplet codons are the predominant form of genetic code in nature, quadruplet codon decoding often displays limited efficiency. In this work, we exploited a new approach to significantly improve quadruplet UAGN and AGGN (N = A, U, G, C) codon decoding efficiency by using recoding signals imbedded in mRNA. With representative recoding signals, the expression level of mutant proteins containing UAGN and AGGN codons reached 48% and 98% of that of the wild-type protein, respectively. Furthermore, this strategy mitigates a common concern of reading-through endogenous stop codons with amber suppression-based system. Since synthetic recoding signals are rarely found near the endogenous UAGN and AGGN sequences, a low level of undesirable suppression is expected. Our strategy will greatly enhance the utility of noncanonical amino acid mutagenesis in live-cell studies.

     
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  5. null (Ed.)
    The susceptibility of austenitic, ferritic, and duplex stain-less steels to solidification cracking was evaluated by the new Transverse Motion Weldability (TMW) test. The focus was on austenitic stainless steels. 304L and 316L were least susceptible, 321 was significantly more susceptible, and 310 was much more susceptible. However, some 321 welds were even less susceptible than 304L welds. These 321 welds were found to have much finer grains to better resist solidification cracking. Quenching 321 during welding revealed spontaneous grain refining could occur by heterogeneous nucleation. For 304L, 316L, and 310, a new explanation for the susceptibility was proposed based on the continuity of the liquid between columnar dendrites; a discontinuous, isolated liquid allows bonding between dendrites to occur early to better resist cracking. In 304L and 316L, the dendrite-boundary liquid was discontinuous and isolated, as revealed by quenching. The liquid was likely depleted by both fast back diffusion into -dendrites (body-centered cubic) and the L +  + reaction, which consumed L while forming . In 310, however, the dendrites were separated by a continuous liquid that prevented early bonding between them. Back diffusion into -dendrites (face-centered cubic) was much slower, and the L +  + reaction formed little . Quenching also revealed skeletal/lacy formed in 304L and 316L well after solidification ended; thus, skeletal/lacy did not resist solidification cracking, as had been widely believed for decades. The TMW test further demonstrated that both more sulfur and slower welding can increase susceptibility. 
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  6. We experimentally demonstrate long-wavelength-infrared (LWIR) femtosecond filamentation in solids. Systematic investigations of supercontinuum (SC) generation and self-compression of the LWIR pulses assisted by laser filamentation are performed in bulk KrS-5 and ZnSe, pumped by∼<#comment/>145fs, 9 µm, 10 µJ pulses from an optical parametric chirped-pulse amplifier operating at 10 kHz of repetition rate. Multi-octave SC spectra are demonstrated in both materials. While forming stable single filament, 1.5 cycle LWIR pulses with 4.5 µJ output pulse energy are produced via soliton-like self-compression in a 5 mm thick KrS-5. The experimental results quantitatively agree well with the numerical simulation based on the unidirectional pulse propagation equation. This work shows the experimental feasibility of high-energy, near-single-cycle LWIR light bullet generation in solids.

     
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  7. Abstract The semiconductor tracker (SCT) is one of the tracking systems for charged particles in the ATLAS detector. It consists of 4088 silicon strip sensor modules.During Run 2 (2015–2018) the Large Hadron Collider delivered an integrated luminosity of 156 fb -1 to the ATLAS experiment at a centre-of-mass proton-proton collision energy of 13 TeV. The instantaneous luminosity and pile-up conditions were far in excess of those assumed in the original design of the SCT detector.Due to improvements to the data acquisition system, the SCT operated stably throughout Run 2.It was available for 99.9% of the integrated luminosity and achieved a data-quality efficiency of 99.85%.Detailed studies have been made of the leakage current in SCT modules and the evolution of the full depletion voltage, which are used to study the impact of radiation damage to the modules. 
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