The effect of pupil transmittance on axial resolution of reflection phase microscopy

A reflection phase microscope (RPM) can be equipped with the capability of depth selection by employing a gating mechanism. However, it is difficult to achieve an axial resolution close to the diffraction limit in real implementation. Here, we systematically investigated the uneven interference contrast produced by pupil transmittance of the objective lens and found that it was the main cause of the practical limit that prevents the axial resolution from reaching its diffraction limit. Then we modulated the power of illumination light to obtain a uniform interference contrast over the entire pupil. Consequently, we could achieve an axial resolution fairly close to the diffraction limit set by the experimental conditions.

Identification Performance During Quarantine by COVID-19 Pandemic: Influence of Emotional Variables and Sleep Quality

The COVID-19 pandemic has caused major disruptions in people’s lives around the globe. Sleep habits and emotional balance have been disturbed in a way that could be comparable to the havoc caused by a deep personal crisis or a traumatic experience. This unfortunate situation provides a unique context in which to study the impact of these imbalances on cognitive processes. In particular, the field of eyewitness science could benefit from these conditions, since they are also often present in crime victims, but can only be generated in the laboratory up to a certain ethical and practical limit. For several decades, eyewitness studies have tried to discover what variables affect people’s ability to properly recognize faces. However, the disparity of experimental designs and the limitations of laboratory work could be contributing to the lack of consensus around several factors, such as sleep, anxiety, and depression. Therefore, the possibility of observing the influence of these agents in natural contexts could shed light on this discussion. Here, we perform simple and repeated lineups with witnesses of mock-crime, considering the conditions related to the COVID-19 pandemic, which to some extent allow emulating the deterioration in general well-being that often afflicts crime victims. For this, 72 participants completed symptomatology scales, and watched a video portraying a staged violent episode. Subsequently, they gave testimony and participated in two lineups, in which we manipulated the presence/absence of the perpetrator, to recreate critical scenarios for the appearance of false recognitions. We found an increase in recognition errors in those individuals who did not have access to the perpetrator during the Initial lineup. Additionally, the conditions of the pandemic appear to have adversely affected the ability to witness and accurately perform lineups. These results reaffirm the need to move toward the standardization of research practices and methods for assessing testimonial evidence, especially in relation to the results of the lineups. Considering the degree of fallibility of these processes can lead to a reduction of wrongful convictions.

Rheology of Highly Concentrated Suspensions with a Bimodal Size Distribution of Solid Particles for Powder Injection Molding

Powder injection molding (PIM) is one of the modern and prospective technologies in processing different materials. We proposed to use bimodal compositions of particles for increasing their content in the final products. A set of model suspension of Al with low-molecular-weight poly (ethylene glycol) as a binder based on theoretical arguments concerning the filling capacity of bimodal suspensions was prepared. Studying the rheological properties of these compositions showed that they demonstrate elasto-viscous behavior with significant plasticity that is favorable for the technological process. Using compositions with bimodal distributions allows for increasing the content of the solid phase up to 75 vol. % for PIM technology, which is significantly higher than the standard practical limit. This rheological approach developed for model formulations was applied to processing compositions containing aluminum oxide as typical ceramics and polyolefines as a binder widely used in technological practice. The obtained sintered ceramic samples have quite acceptable mechanical properties of the usual corundum articles.

Synthesis of a synthetic analogue for the Sitophilus weevil aggregation pheromone and study on its hygienic and toxicological indexes

The work was initiated to study hygienic and toxicological indices of a synthetic analogue for the Sitophilus weevil aggregation pheromone. The toxicity testing of 5-hydroxy-4-methyl-3-heptanone demonstrated its extremely low toxicity for the warm-blood animals, as compared to the one of the typical pesticides. The average lethal dose of the product per orally administered to the white mice was established to be 4375.0 mg kg-1 LD16 and LD84 being 2225.0 mg kg-1 and 6550.0 mg kg-1, respectively. The average lethal dose for rabbits was 5900.0 mg kg-1 5-hydroxy-4-methyl-3-heptanone proved to have a mild skin and conjunctival irritant action, and equally mild functional cumulation. As to chronic toxicity, the acceptable daily dose of 4.3 mg/person/d was calculated and scientifically substantiated. The odor threshold was determined at the dose ranging from 0.35 to 0.7 mg l-1 with the practical limit ranging from 0.35 to 1.5 mg l-1, taste sensation threshold was found at the dose ranging from 1.0 to 3.0 mg l-1 with the practical limit ranging from 3.0 to 7.0 mg l-1

Clique Listing Algorithms and Characteristics of Cliques in Random Graphics

In this thesis we address three main problems in clique detection in the area of Graph Theory. i) Most of current methods for clique detection are time consuming (can take exponential time to the size of input graph), so there is a practical limit on size of input graph. In this thesis we propose three different methods for estimating the number of cliques. We examine these methods for various graphs and conclude that they efficiently find the number of cliques within 5% error typically. ii) We compare various versions of the Bron-Kerbosch (BK) clique listing algorithm to discover a method of combining the best features of different versions. We test our new versions of BK for various inputs. iii) We study the characteristics of cliques in random graphs as a function of size and density.

Clique Listing Algorithms and Characteristics of Cliques in Random Graphics

In this thesis we address three main problems in clique detection in the area of Graph Theory. i) Most of current methods for clique detection are time consuming (can take exponential time to the size of input graph), so there is a practical limit on size of input graph. In this thesis we propose three different methods for estimating the number of cliques. We examine these methods for various graphs and conclude that they efficiently find the number of cliques within 5% error typically. ii) We compare various versions of the Bron-Kerbosch (BK) clique listing algorithm to discover a method of combining the best features of different versions. We test our new versions of BK for various inputs. iii) We study the characteristics of cliques in random graphs as a function of size and density.

New Directions in Space Art

<p>New developments in the space industry, falling costs and a diversity of launch platforms are altering the conditions of access to space. The thesis examines to what extent cultural practice is enabled by these new relations. A brief historical overview details the cultural use of space and highlights the history of art satellites. This provides context for a detailed discussion of a satellite artwork by the author, "The Weight of Information". Auto-ethnographic and design-ethnographic techniques are used to explore the artwork through four situations. The setting of interfaces, form factors, boundaries and miniaturisation are found to be enabling mechanisms for cultural practice in space, while the developing space debris regulatory environment is found to provide a practical limit to further miniaturisation of space craft. The tension between the personal and infrastructural is examined through different concepts of entanglement. Strategies of tragedy, participation and correspondence that address issues of accessibility and contingency specific to cultural practice in the orbital environment are explored. Recommendations are made for practitioners wishing to work with art satellites. It is concluded that new developments in the space industry are enabling of future cultural practice in space. </p>

New Directions in Space Art

<p>New developments in the space industry, falling costs and a diversity of launch platforms are altering the conditions of access to space. The thesis examines to what extent cultural practice is enabled by these new relations. A brief historical overview details the cultural use of space and highlights the history of art satellites. This provides context for a detailed discussion of a satellite artwork by the author, "The Weight of Information". Auto-ethnographic and design-ethnographic techniques are used to explore the artwork through four situations. The setting of interfaces, form factors, boundaries and miniaturisation are found to be enabling mechanisms for cultural practice in space, while the developing space debris regulatory environment is found to provide a practical limit to further miniaturisation of space craft. The tension between the personal and infrastructural is examined through different concepts of entanglement. Strategies of tragedy, participation and correspondence that address issues of accessibility and contingency specific to cultural practice in the orbital environment are explored. Recommendations are made for practitioners wishing to work with art satellites. It is concluded that new developments in the space industry are enabling of future cultural practice in space. </p>

New Directions in Space Art

<p>New developments in the space industry, falling costs and a diversity of launch platforms are altering the conditions of access to space. The thesis examines to what extent cultural practice is enabled by these new relations. A brief historical overview details the cultural use of space and highlights the history of art satellites. This provides context for a detailed discussion of a satellite artwork by the author, "The Weight of Information". Auto-ethnographic and design-ethnographic techniques are used to explore the artwork through four situations. The setting of interfaces, form factors, boundaries and miniaturisation are found to be enabling mechanisms for cultural practice in space, while the developing space debris regulatory environment is found to provide a practical limit to further miniaturisation of space craft. The tension between the personal and infrastructural is examined through different concepts of entanglement. Strategies of tragedy, participation and correspondence that address issues of accessibility and contingency specific to cultural practice in the orbital environment are explored. Recommendations are made for practitioners wishing to work with art satellites. It is concluded that new developments in the space industry are enabling of future cultural practice in space. </p>

Toward the Super Temporal Resolution Image Sensor with a Germanium Photodiode for Visible Light

The theoretical temporal resolution limit tT of a silicon photodiode (Si PD) is 11.1 ps. We call “super temporal resolution” the temporal resolution that is shorter than that limit. To achieve this resolution, Germanium is selected as a candidate material for the photodiode (Ge PD) for visible light since the absorption coefficient of Ge for the wavelength is several tens of times higher than that of Si, allowing a very thin PD. On the other hand, the saturation drift velocity of electrons in Ge is about 2/3 of that in Si. The ratio suggests an ultra-short propagation time of electrons in the Ge PD. However, the diffusion coefficient of electrons in Ge is four times higher than that of Si. Therefore, Monte Carlo simulations were applied to analyze the temporal resolution of the Ge PD. The estimated theoretical temporal resolution limit is 0.26 ps, while the practical limit is 1.41 ps. To achieve a super temporal resolution better than 11.1 ps, the driver circuit must operate at least 100 GHz. It is thus proposed to develop, at first, a short-wavelength infrared (SWIR) ultra-high-speed image sensor with a thicker and wider Ge PD, and then gradually decrease the size along with the progress of the driver circuits.