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Microfossils of fish teeth and denticles, referred to as ichthyoliths, provide critical information for depositional ages, paleo‐environments, and marine ecosystems, especially in pelagic realms. However, owing to their small size and rarity, it is time‐consuming and difficult to analyze large numbers of ichthyoliths from sediment samples, limiting their use in scientific studies. Here, we propose a method to automatically detect ichthyoliths from microscopic images using a deep learning technique. We applied YOLO‐v7, one of the latest object detection architectures, and trained several models under different conditions. The model trained under appropriate conditions with an original data set achieved an F1 score of 0.87. We then enhanced the data set efficiently using the pre‐trained model. We validated the practical applicability of the model by comparing the number of ichthyoliths detected by the model with those counted manually. This revealed that the best model can predict the number of triangular teeth, denticles and irregularly shaped teeth with minimal human intervention. This object detection method can extend the applicability of deep learning to a wider array of microfossils and has the potential to dramatically increase the spatiotemporal resolution of ichthyolith records for applications across disciplines. Plain Language Summary: Fossils of fish teeth and denticles, referred to as ichthyoliths, can be used to study the environmental changes of marine conditions throughout Earth's history. However, it is time‐consuming and difficult to analyze large numbers of ichthyoliths from sediment samples, limiting their use in scientific studies. Here, we trained several artificial intelligence models to automatically detect ichthyoliths from microscopic images. The best model is suitable for counting the number of fish teeth, denticles, and irregularly shaped teeth fragments with minimal human intervention. We propose that object detection, a deep learning technique used in this study, can be applicable for the study of various microfossils, as well as for increasing the spatiotemporal resolution of ichthyolith records. Key Points: We trained object detection models under different conditions to detect microfossil fish teeth and denticles from microscopic imagesThe best model can count teeth, denticles and irregularly shaped teeth from samplesObject detection may improve the observation efficiency of a wide array of microfossils [ABSTRACT FROM AUTHOR]

The Strelley Pool Formation ( SPF) is widely distributed in the East Pilbara Terrane ( EPT) of the Pilbara Craton, Western Australia, and represents a Paleoarchean shallow-water to subaerial environment. It was deposited ~3.4 billion years ago and displays well-documented carbonate stromatolites. Diverse putative microfossils ( SPF microfossils) were recently reported from several localities in the East Strelley, Panorama, Warralong, and Goldsworthy greenstone belts. Thus, the SPF provides unparalleled opportunities to gain insights into a shallow-water to subaerial ecosystem on the early Earth. Our new micro- to nanoscale ultrastructural and microchemical studies of the SPF microfossils show that large (20-70 μm) lenticular organic-walled flanged microfossils retain their structural integrity, morphology, and chain-like arrangements after acid ( HF- HCl) extraction (palynology). Scanning and transmitted electron microscopy of extracted microfossils revealed that the central lenticular body is either alveolar or hollow, and the wall is continuous with the surrounding smooth to reticulated discoidal flange. These features demonstrate the evolution of large micro-organisms able to form an acid-resistant recalcitrant envelope or cell wall with complex morphology and to form colonial chains in the Paleoarchean era. This study provides evidence of the evolution of very early and remarkable biological innovations, well before the presumed late emergence of complex cells. [ABSTRACT FROM AUTHOR]

The 3.4-Ga Strelley Pool Formation ( SPF) at the informally named 'Waterfall Locality' in the Goldsworthy greenstone belt of the Pilbara Craton, Western Australia, provides deeper insights into ancient, shallow subaqueous to possibly subaerial ecosystems. Outcrops at this locality contain a thin (<3 m) unit of carbonaceous and non-carbonaceous cherts and silicified sandstones that were deposited in a shallow-water coastal environment, with hydrothermal activities, consistent with the previous studies. Carbonaceous, sulfide-rich massive black cherts with coniform structures up to 3 cm high are characterized by diverse rare earth elements ( REE) signatures including enrichment of light [light rare earth elements ( LREE)] or middle rare earth elements and by enrichment of heavy metals represented by Zn. The massive black cherts were likely deposited by mixing of hydrothermal and non-hydrothermal fluids. Coniform structures in the cherts are characterized by diffuse laminae composed of sulfide particles, suggesting that unlike stromatolites, they were formed dominantly through physico-chemical processes related to hydrothermal activity. The cherts yield microfossils identical to previously described carbonaceous films, small and large spheres, and lenticular microfossils. In addition, new morphological types such as clusters composed of large carbonaceous spheroids (20-40 μm across each) with fluffy or foam-like envelope are identified. Finely laminated carbonaceous cherts are devoid of heavy metals and characterized by the enrichment of LREE. This chert locally contains conical to domal structures characterized by truncation of laminae and trapping of detrital grains and is interpreted as siliceous stromatolite formed by very early or contemporaneous silicification of biomats with the contribution of silica-rich hydrothermal fluids. Biological affinities of described microfossils and microbes constructing siliceous stromatolites are under investigation. However, this study emphasizes how diverse the microbial community in Paleoarchean coastal hydrothermal environment was. We propose the diversity is at least partially due to the availability of various energy sources in this depositional environment including reducing chemicals and sunlight. [ABSTRACT FROM AUTHOR]

The article presents case studies on the occurrence of amniotic fluid in patients with subchorionic hematoma. A 35-year-old pregnant woman experienced preterm premature rupture of membranes and emergency Cesarean section following the discovery of subchorionic hematoma and amniotic fluid sludge by ultrasonography. A 29-year-old woman suffered from miscarriage with histological chorioamnionitis following the diagnosis of subchorionic hematoma and amniotic fluid sludge by ultrasound.

For the purpose of establishing a standard method for the gas chromatographic determination of fatty acid composition, a collaborative study team has carried out replicate analyses of specified samples using gas chromatographs equipped with thermal conductivity detectors and has examined the entire set of experimental data by a statistical method. From the results of the four collaborative works it was found that deviation of analytical values from exact composition and interlaboratory scattering of data may be considerably decreased by the following means: (a) enlarging the size of narrow peaks (less than 5 mm at a half height) or peaks with low height by adjusting the attenuator range or chart speed; (b) correcting the analytical values by using correction factors determined from analysis of known mixtures having composition similar to that of an unknown sample. [ABSTRACT FROM AUTHOR]

An abstract of the article "Immune tolerance induction using chorionic villus sampling (CVS) technique in rodent models" by M. Endo and colleagues is presented.

The aim of this study was to assess public attitudes toward the promotion of genomic studies related to medicine and to examine the relationship between public attitudes and the level of genomic literacy by analyzing data from a nationwide opinion survey. The participants comprised 4,000 people (age, 20-69) selected from the Japanese general population by using the two-step stratified random sampling method. They were queried on the following topics in a mail survey: (1) pros and cons of the promotion of genomic studies related to medicine, (2) level of scientific literacy in genomics, (3) demographic and socioeconomic background, and (4) knowledge and attitudes toward science in general and genetic testing in particular. We examined the relationship between the approval of promotion and literacy level, using logistic regression models stratified by gender. Our results showed the response rate was 54.3% (2,171/4,000), and 69.4% participants favored the promotion of genomic studies related to medicine. Only 1.3% participants expressed a negative attitude. Multivariate analysis revealed that approval of promotion was related to a high literacy score. This relationship was stronger in males than in females (the highest quartile of score vs. the lowest: adjusted odds ratio, 3.36 for males and 1.86 for females; 95% confidence interval, 1.88-5.98 for males and 1.17-2.95 for females). We determined that a majority of the Japanese participants currently approved of the promotion of genomic studies related to medicine and that people with a high level of genomic literacy tended to approve the promotion., ((c) 2008 Wiley-Liss, Inc.)

Problem: The human tumor-associated receptor-binding cancer antigen expressed on SiSo cells (RCAS1) is considered to play a role in the inhibition of the maternal immune response during pregnancy. The aim of our study was to investigate the expression of RCAS1 protein in the placenta and to compare its concentration in maternal and cord blood sera between normal pregnancies and pregnancies complicated by gestational diabetes mellitus (GDM)., Method of Study: Samples were obtained from women with GDM (n = 8), women with type 1 DM (n = 5), and healthy term controls (n = 27) after delivery. Placentas were studied by immunohistochemistry, and real-time polymerase chain reaction. For assessment of RCAS1 concentrations in maternal and cord blood sera, enzyme-linked immunosorbent assay was performed., Results: The RCAS1 protein mRNA expression in the placentas of patients with GDM was significantly lower than that in the controls (P = 0.005). The maternal blood RCAS1 protein concentration of the GDM cases was also significantly lower than that in the controls (P = 0.0411), whereas the cord blood RCAS1 protein concentration was significantly higher in the GDM and type 1 DM groups than in the controls (P = 0.0311 and P = 0.0192, respectively)., Conclusion: The present results suggest that RCAS1 protein might have an important role in the development of GDM.