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Schistosomiasis is a parasitic disease with significant global health and socio-economic implications. Drug discovery for schistosomiasis typically involves high-content whole-organism screening. In this approach, parasites are ex-posed to various chemical compounds and their systemic, whole-organism-level responses are captured via microscopy and analyzed to obtain a quanti-tative assessment of chemical effect. These effects are multidimensional and time-varying, impacting shape, appearance, and behavior. Accurate identifi-cation of object boundaries is essential for preparing images for subsequent analysis in high-content studies. Object segmentation is one of the most deeply studied problems in computer vision where recent efforts have incor-porated deep learning. Emerging results indicate that acquiring robust fea-tures in spectral domain using Fast Fourier Transform (FFT) within Deep Neural Networks (DNNs) can enhance segmentation accuracy. In this paper, we explore this direction further and propose a latent space Phase-Gating (PG) method that builds upon FFT and leverages phase information to effi-ciently identify globally significant features. While the importance of phase in analyzing signals has long been known, technical difficulties in calculat-ing phase in manners that are invariant to imaging parameters has limited its use. A key result of this paper is to show how phase information can be in-corporated in neural architectures that are compact. Experiments conducted on complex HCS datasets demonstrate how this idea leads to improved seg-mentation accuracy, while maintaining robustness against commonly en-countered noise (blurring) in HCS. The compactness of the proposed method also makes it well-suited for application specific architectures (ASIC) de-signed for high-content screening. 

Abstract We have investigated crystalline AlGaAs/GaAs optical coatings with three ultra-stable cavities operating at 4 K, 16 K, 124 K and 297 K. The response of the cavities’ resonance frequencies to variations in optical power indicates non-thermal effects beyond the photo-thermo-optic effect observed in dielectric coatings. These effects are strongly dependent on the intensity of the intracavity light at 1.5 μm. When the rear side of the mirrors is illuminated with external light, we observe a prominent photo-modified birefringence for photon energies above the GaAs bandgap, which points to a possible mechanism relating our observations to the semiconductor properties of the coatings. Separately, we also present a low maintenance evolution of our 124 K silicon cavity system where the liquid nitrogen based cooling system is replaced with closed cycle cooling from a pulse-tube cryo-cooler. 

Site U1586 is the deepest (4692 meters below sea level [mbsl]) and farthest site from shore (170 km) drilled during Expedition 397 (Figures F1, F2, F3). It is located near the toe of the Promontório dos Príncipes de Avis at Common Midpoint (CMP) 1330 on Cruise JC89 Seismic Line 2 near the intersection of Cruise JC089 Line 3 (Figures F4, F5, F6). The continental slope environment is prone to failure and mass transport deposits (MTDs), and large disturbances are recognizable features on seismic profiles. For example, Site U1586 is between two MTDs or disturbed intervals at about 6.3 and 6.5 s two-way traveltime (TWT) on Cruise JC089 Seismic Line 2 near CMPs 1170–1250 and around CMP 1350 (Figure F5). Site U1586 is located where there is good continuity of reflectors to avoid these MTDs, but disturbances may still occur on a shorter length scale than the resolution of the seismic profiles. The target drilling depth of 350 meters below seafloor (mbsf) corresponds to the top of a package of chaotic high-amplitude reflections at 6.6 s TWT that was initially estimated to be late Miocene (~7 Ma) but was later determined biostratigraphically to be middle Miocene (~14 Ma) on the basis of shipboard micropaleontological analyses. The primary scientific objective of Site U1586 was to recover a deep distal record from a water depth of ~4690 mbsl. The sediment thickness thins toward the toe of the Promontório dos Príncipes de Avis owing to lower sedimentation rates with increased distance from shore. Interpretation of the seismic profiles suggests the sequence spans the late Miocene to Quaternary with an average sedimentation rate of 5 cm/ky. Recovery of late Miocene sediment at this site will complement sequences to be drilled during International Ocean Discovery Program (IODP) Expedition 401 to study the exchange between the Mediterranean and Atlantic for the period before, during, and after the Messinian Salinity Crisis (5.96–5.33 Ma) (Flecker et al., 2023). The sediments will also provide a history of surface and deepwater conditions through the Pliocene, including the mid-Pliocene warm period, when atmospheric CO2 was similar to today (400 ppm). Sediments recovered at Site U1586 will also be useful for studying how surface and deep oceanographic conditions responded to the intensification of Northern Hemisphere glaciation in the late Pliocene (~2.9 Ma). Site U1586 is under the influence of Lower Deep Water (LDW), which consists of Antarctic Bottom Water whose properties have been modified significantly from its origin in the high-latitude South Atlantic (Figure F7). This site's great depth may result in carbonate microfossil dissolution, although a 7.45 m piston core (JC089-5-3P) and 4.68 m kasten core (JC089-5-3K) recovered at the same location show continuous preservation of foraminifers during the last glacial stage and Holocene. Results from shipboard analyses during Expedition 397 further show that carbonate preservation and abundance of calcareous microfossils extends back to the Miocene (see Biostratigraphy). Sedimentation rates in the piston core average 11 cm/ky. The Ca/Ti and Zr/Sr measured using core scanning X-ray fluorescence (XRF) show distinct millennial events (Channell et al., 2018), with particularly notable peaks in Zr/Sr marking each of the Heinrich stadials of the last glacial period (Figure F8). Study of Site U1586 cores will permit the reconstruction of changes in ventilation and carbon storage in the deepest Atlantic on glacial–interglacial and millennial timescales with potential implications for atmospheric CO2 changes. Preservation of terrestrial biomarkers and pollen will permit reconstruction of vegetation changes in Europe. Lastly, it should be possible to correlate physical properties at Site U1586 into the Mediterranean cyclostratigraphy, thereby permitting regional climate change to be placed into a global context. 

Site U1587 is the second farthest from shore drilled during Expedition 397 and located at a water depth of 3479 meters below sea level (mbsl) (Figures F1, F2, F3). It is the second deepest site along the bathymetric transect and is bathed today by a mixture of ~75% North Atlantic Deep Water (NADW) and 25% Lower Deep Water (LDW) sourced from the Southern Ocean (Figure F4) (Jenkins et al., 2015). The mixing ratio of these water masses and their vertical position in the water column has changed in the past, which has implications for ventilation and carbon storage in the deep Atlantic Ocean. The location of Site U1587 was motivated by the clear expression of millennial climate variability in proxy records of oxygen isotopes and sea-surface temperature in nearby Piston Core MD95-2042 (Shackleton et al., 2000, 2004; Bard et al., 2000; Pailler and Bard, 2002; Davtian and Bard, 2023). Isotopic, organic biomarker, and pollen results from this core demonstrated the potential of correlating Iberian margin sediments with ice cores from Greenland and Antarctica and with European terrestrial sequences (e.g., Sánchez-Goñi et al., 2000; Margari et al., 2010, 2014, 2020). The sediment record from Site U1587 provides the opportunity to develop sediment proxy records for the Greenland and Antarctic ice cores to the base of the Quaternary and beyond. The piston core (JC089-04-2P) recovered near Site U1587 is 10.7 m long and has a sedimentation rate of 17 cm/ky (Figure F5). Ca/Ti and Zr/Sr show strong evidence of millennial variability during the last glacial cycle. The objective for Site U1587 is to study such variability for older glacial cycles throughout the Quaternary. Site U1587 is located at the intersection of Seismic Lines JC089-6 and JC089-7 (Figure F6). Although mass transport deposits or disturbed intervals are developed nearby, the continuity of reflections is good at Site U1587 (Figures F7, F8). The Upper Miocene to Quaternary sequence at Site U1587 is expanded relative to Site U1586 and is more than 500 m thick. Sedimentation rates are estimated to average ~10 cm/ky at Site U1587, or about twice that of Site U1586. We had permission from the Environmental Protection and Safety Panel (EPSP) to drill to 500 meters below seafloor (mbsf), but we requested and were granted permission to drill an additional 50 m to extend the record well into the late Miocene. Site U1587 provides an expanded sequence of late Miocene to Quaternary sediments with which to address the following objectives: Document how millennial climate variability evolved during the glacial cycles of the Quaternary and Pliocene as boundary conditions changed with the progressive intensification of Northern Hemisphere glaciation (NHG). Reconstruct the history of changing local dominance of northern-sourced versus southern-sourced deep water, as well as ventilation and carbon storage in the deep Atlantic Ocean. Determine interhemispheric phase relationships (leads/lags) by comparing the timing of proxy variables that monitor surface (Greenland) and deepwater (Antarctic) components of the climate system. Investigate climate during past interglacial periods, including the warm Pliocene period prior to the intensification of NHG. Link terrestrial, marine, and ice core records by analyzing pollen and terrestrial biomarkers that are delivered to the deep-sea environment of the Iberian margin. Recover a complete record of the time leading up to, during, and following the Messinian Salinity Crisis, which complements objectives of International Ocean Discovery Program (IODP) Expedition 401 (Flecker et al., 2023) and will permit evaluation of the causes and consequences of this remarkable event in Earth's history. Develop an orbitally-tuned age model for Site U1587 by correlating physical properties to eccentricity-modulated precession and tying them into the record of Mediterranean cyclostratigraphy.