Spatial frequencies in aesthetic website evaluations--explaining how ultra-rapid evaluations are formed

This study investigates how aesthetic website evaluations, especially those formed after very brief presentations, depend on visual information that is encoded in low- or high-spatial frequencies. A total of 92 participants took part in the experiment. The study used a 3 × 3 mixed design in which presentation time (50, 500 and 10000 ms) and spatial filtering (low-pass filtered, high-pass filtered and unfiltered stimuli) were manipulated. First, we replicate prior results from online studies of high- and low-spatial frequencies. Second, we confirm a prediction from neurocognitive models that only low-spatial frequencies are relevant to aesthetic judgements in ultra-rapid presentation modes. Third, we demonstrate that stimulus repetitions lead to an overestimation of the importance of ultra-rapid stimulus presentations. Taken together, our results highlight the utility of neurocognitive models of visual processing to explain the rapid aesthetic evaluation of websites. PRACTITIONER SUMMARY: Using neurocognitive models we present an approach to explain how aesthetic impressions are formed. We show that ultra-rapid judgements are connected with low- but not with high-spatial frequencies, which are neurologically processed in different visual pathways. Furthermore we identify possible methodological problems in previous studies of ultra-rapid website perception.     

Microscopy under pressure--an optical chamber system for fluorescence microscopic analysis of living cells under high hydrostatic pressure

High hydrostatic pressure (HHP) becomes more and more interesting for life science research, since it can be employed to inactivate various cells. To directly monitor "cells under pressure," the development of an optical high-pressure chamber is required. Therefore, an optical pressure chamber that can be used for up to 300 MPa was constructed. This chamber has already been described as a tool for in situ observation of dynamic changes of microscopic structures in bright field as well as phase contrast. In combination with an inverted microscope, we obtained brilliant microscopic color pictures with an optical resolution more than 0.56 microm. Here, we demonstrate the capabilities of the HHP cell, in combination with epifluorescence microscopy. Using a nonadherent human B-cell line (Raji, ATCC CCL 86), stained with the fluorescent dyes propidium iodide, Hoechst 33342, or dihexyloxacarbocyanine iodide, we were able to show that the system is suitable to perform fluorescence microscopic analyses, with pressures up to 300 MPa, with viable mammalian cells.     

The Inventory Approach to Urban Growth Boundaries

In this article, we argue that insights can be gained by analyzing the use of urban growth boundaries (UGBs) for urban growth management as an inventory problem. The analysis provides three useful insights. First, it shows that where UGBs are employed, too much emphasis is placed on whether UGBs contain sufficient land to accommodate 20 years of growth and too little is placed on how frequently, how much, or under what circumstances UGBs should be expanded. Second, it shows that where market factors are used, they have been used inappropriately to increase the size of UGBs immediately after expansion, when they should be used to influence the size of UGBs immediately before expansion. Third, it shows that UGBs are likely to work better if expansions occur not after an arbitrary period of time, but when the supply—or the price—of land reaches some critical threshold. We conclude by asserting that the use of UGBs should not be governed by arbitrary rules of thumb, because such rules do not stand up to critical examination, they preclude adaptation to local situations, and they prevent experimentation.     

Predicting Chicago's Land Use Pattern

The planning of community facilities requires accurate quantitative estimates of the area, type, intensity, and location of land uses required by the growth of urban activities. The distribution of these activities and the intensity of their use of land are highly related to accessibility as measured by distance from the CBD. This paper outlines a procedure whereby area-wide estimates of future population and economic activity can be distributed to small subareas so that measures of local land requirements may be obtained.     

Mutations Closer to the Active Site Improve the Promiscuous Aldolase Activity of 4‐Oxalocrotonate Tautomerase More Effectively than Distant Mutations

The enzyme 4‐oxalocrotonate tautomerase (4‐OT), which catalyzes enol–keto tautomerization as part of a degradative pathway for aromatic hydrocarbons, promiscuously catalyzes various carbon–carbon bond‐forming reactions. These include the aldol condensation of acetaldehyde with benzaldehyde to yield cinnamaldehyde. Here, we demonstrate that 4‐OT can be engineered into a more efficient aldolase for this condensation reaction, with a >5000‐fold improvement in catalytic efficiency (k_cat/K_m) and a >10⁷‐fold change in reaction specificity, by exploring small libraries in which only “hotspots” are varied. The hotspots were identified by systematic mutagenesis (covering each residue), followed by a screen for single mutations that give a strong improvement in the desired aldolase activity. All beneficial mutations were near the active site of 4‐OT, thus underpinning the notion that new catalytic activities of a promiscuous enzyme are more effectively enhanced by mutations close to the active site.     

Isolation and characterization of a Δ-9 fatty acid desaturase gene from the oleaginous yeast Cryptococcus curvatus CBS 570

The oleaginous yeast Cryptococcus curvatus is of industrial interest because it can accumulate triacylglycerols up to 60% of the cell dry weight. We are aiming at genetic modification of fatty acid biosynthesis for the production of tailor-made triacylglycerols in C. curvatus. As a first step in the development of a transformation and expression system a gene encoding the Δ-9 fatty acid desaturase of C. curvatus (CBS 570) was cloned. The 1470 bp gene encodes a protein of 493 amino acids with a calculated molecular mass of 55 kDa. The gene shows strong similarity to previous cloned Δ-9 desaturase genes from rat and Saccharomyces cerevisiae, 62 and 72%, respectively. Expression of the Δ-9 desaturase gene was studied. Supplementation of the growth medium with oleic acid (C18:1(c9)) showed a strong repression (90%) on the mRNA level, while supplementation with petroselinic acid (C18:1(c6)) had no effect on the amount of mRNA.     

Impact of Spatially Heterogeneous Trop-2 Expression on Prognosis in Oral Squamous Cell Carcinoma

Oral cancer often presents with aggressive behavior and a high risk of recurrence and metastasis. For oral squamous cell carcinoma (OSCC), which is the most frequent histological subtype, therapy strategies include surgery, radiation therapy, chemotherapy, immune checkpoint inhibitors, and EGFR inhibitors. Recently, a Trop-2 antibody-drug conjugate (ADC) has been approved in the United States of America for the treatment of advanced triple-negative breast cancer. However, this ADC has also been tested in other solid tumors including head & neck squamous cell carcinoma. The prognostic impact of Trop-2 has already been reported for several cancers. We studied the prognostic influence of Trop-2 protein expression on OSCC patients’ survival. The cohort comprised n = 229 OSCC patients with available archived tumor tissue and corresponding non-neoplastic oral mucosa tissue. Using immunohistochemistry, we investigated Trop-2 expression in both the central and peripheral regions of each tumor and in corresponding non-neoplastic oral mucosa. In patients suffering from OSCC with combined high central and low peripheral Trop-2 expression, five-year overall survival (OS) was 41.2%, whereas 55.6% of OSCC patients who presented lower central and/or higher peripheral tumoral Trop-2 expression were alive after five years (p = 0.075). In multivariate Cox regression, the expression pattern of high central tumoral and lower peripheral Trop-2 expression was significantly correlated with impaired OS (HR = 1.802, 95%-CI: 1.134–2.864; p = 0.013) and recurrence-free survival (RFS) (HR = 1.633, 95%-CI: 1.042–2.560; p = 0.033), respectively, when adjusting for co-variables. Hence, Trop-2 may serve as an independent prognostic biomarker in OSCC. In subsequent studies, the pathophysiological meaning of downregulated Trop-2 expression in the OSCC periphery has to be analyzed.     

On the Origin of a Low Angle Spacing in Starch

The structure of starch granules from different botanical sources was studied by transmission electron microscopy and small-angle X-ray diffraction. Electron micrographs of negatively stained starch granule fragments show a rippled fibrous structure. The ripples are interpreted as being stacks of thin crystalline lamellae comprising the linear α-(1→4) chains of the amylopectin. Optical diffraction analysis of the electron micrographs showed that the spacing of the ripples varies from 9.2 nm in potato starch to 10.4 nm in barley starch. This correlates well with the position of a Bragg peak at appr. 10 nm measured by small-angle X-ray diffraction. These observations indicate that the Bragg peak arises from the alternating amorphous and crystalline regions seen as ripples in the electron micrographs.     

Designing spaces for every listener

Inclusive design aims at objects and environments that are accessible, usable and comfortable for all people throughout their entire lifespan. In architecture, this aim is usually associated with physical accessibility. Yet acoustic qualities may considerably impact usability and comfort as well, especially in spaces for listening. This case study explores the notion of acoustic comfort for all in the context of university education. One auditorium, situated in a historic building and subject to renovation in the near future, is studied in detail: acoustic obstacles are identified in collaboration with user/experts and are measured in situ; specific interventions are proposed in consultation with building professionals, technicians and conservation specialists and are tested using dedicated acoustic simulation software. The study draws attention to the importance of acoustic comfort for all and offers a first view of which solutions are possible and desirable and how these can be obtained.