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Many sophisticated numerical methods have been developed to evaluate soil responses. However, the lack of referential stress–strain behavior under complicated in-situ ground conditions makes it difficult to validate the obtained responses sufficiently. For example, under a long embankment, with imposing plane strain conditions in depth, allowing for both horizontal displacement toward the slope toe and settlement, the stress components change as a result of the interaction between one soil part and adjacent soil parts. Since those stress conditions themselves are unknown, no laboratory experimental data can be provided to validate a constitutive model. Therefore, the author considered that studying the stress conditions in the ground would play an important role in confirming the calculated results obtained by a numerical method. Soil stress cells have sometimes been utilized to measure the earth pressure in an experimental model, but such measurements have often proven to be unreliable or unrealistic. However, the preciseness of earth pressure meters has recently been examined and improved. Recently, centrifuge tests were conducted to estimate the shear stress in a horizontally layered model ground during shaking. By using a pair of earth pressure meters and the concept of Mohr’s stress circle, it was possible to estimate the shear stress at any point in the ground. The shear stress estimated by this method was seen to agree well with the results obtained by a calculation based on the force balances of the supposed soil blocks from the ground surface. As a result, it was confirmed that the proposed method is a promising way to estimate the shear stress in the ground and is worthy of further investigation.

Freshwater crayfish are amongst the largest macroinvertebrates and play a keystone role in the ecosystems they occupy. Understanding the global distribution of these animals is often hindered due to a paucity of distributional data. Additionally, non-native crayfish introductions are becoming more frequent, which can cause severe environmental and economic impacts. Management decisions related to crayfish and their habitats require accurate, up-to-date distribution data and mapping tools. Such data are currently patchily distributed with limited accessibility and are rarely up-to-date. To address these challenges, we developed a versatile e-portal to host distributional data of freshwater crayfish and their pathogens (using Aphanomyces astaci, the causative agent of the crayfish plague, as the most prominent example). Populated with expert data and operating in near real-time, World of Crayfish™ is a living, publicly available database providing worldwide distributional data sourced by experts in the field. The database offers open access to the data through specialized standard geospatial services (Web Map Service, Web Feature Service) enabling users to view, embed, and download customizable outputs for various applications. The platform is designed to support technical enhancements in the future, with the potential to eventually incorporate various additional features. This tool serves as a step forward towards a modern era of conservation planning and management of freshwater biodiversity.

Introduction Cryosurgery is recognized as a treatment option for various types of oral lesions. Although cryosurgery is less invasive and easier to perform than surgical treatments, adverse events, such as stomatitis and scarring can occur if the freezing is excessive. There are few studies regarding the effects of cryosurgery on the surrounding soft tissues. Thus, this study investigated the extent of tissue destruction and healing progress in tongues of mice who underwent cryosurgery. Methods Eight-week-old male BALB/c mice were used. An instrument cooled with liquid nitrogen was lightly touched on the right side of the tongue for 5 s, and a second test was performed 10 s later. Histological evaluation was performed 3, 7, and 14 days after cryosurgery. Blood vessels were evaluated with India ink at 1, 3, 7, 14, and 21 days after cryosurgery. Results Destruction of the soft tissue spread to the left side of the tongue after 3 days. At 7 days, it was confirmed that the muscle tissue was in the process of repair and was completely repaired at 14 days. Although blood vessels were not confirmed at 3 days, they were visible after seven days and were confirmed at 21 days all over the tongue. Discussion and Conclusion These results indicated that the tissue destruction caused by cryosurgery was extensive and suggest that the duration and frequency of freezing should be minimized for clinical use. Lay Summary Cryosurgery is a treatment method for various types of oral lesions. Freezing the lesion causes the tissue to collapse, resulting in its disappearance. Although cryosurgery is less invasive and easier to perform than surgical treatments, adverse events, such as stomatitis and scarring can occur if the freezing is excessive. This study investigated the extent of tissue destruction and healing progress in tongues of mice who underwent cryosurgery. The right side of mice tongues were frozen by an instrument cooled with liquid nitrogen for 5 s, and a second test was performed 10 s later. The tissue destruction was evaluated at 3, 7, and 14 days after freezing. Blood vessels were evaluated with India ink at 1, 3, 7, 14, and 21 days after freezing. Tissue destruction spread to the left side of the tongue after 3 days. At 7 days, it was confirmed that the muscle tissue was in the process of repair and was completely repaired at 14 days. Blood vessel repair was confirmed at 21 days in the throughout tongue. These results indicated that the tissue destruction caused by cryosurgery was large and suggest that the duration and frequency of freezing should be minimized for clinical use.

Xanthogranuloma is a granulomatous lesion associated with histiocytic proliferation and lipid accumulation. It occurs as solitary or multiple smooth-surfaced papules or nodules. It generally appears on the skin in infancy and childhood, in which case it is known as juvenile xanthogranuloma, although a few adult-onset cases have also been reported. Adult-onset cases are known as adult-onset xanthogranuloma, and adult-onset xanthogranuloma of the tongue is extremely rare. The disease is difficult to diagnose clinically; it is instead diagnosed histopathologically in most cases. We herein report a case of adult-onset xanthogranuloma of the tongue.

The phenology of the alga-dwelling amphipod Ceinina japonica Stephensen, 1933 (Amphipoda: Eophliantidae) was studied at Rishiri Island, Hokkaido, Japan, from May 2016 to March 2017. Seasonal shifting between the host algal species was confirmed through observations at a coastal field site and a nearby aquaculture facility for kelp. Amphipods mainly occurred in the farmed biennial kelp Saccharina japonica var. ochotensis and wild algae Undaria pinnatifida, with Agarum clathratum, Costaria costata, Saccharina cichorioides, and Sargassum boreale as new host algal records. Amphipods occurred in sporophytes of U. pinnatifida at the field site from February to March and from May to July, but they were found in the kelp of S. j. var. ochotensis during the rest of the year, from August to the following January. Individuals of C. japonica infected sporophytes of the large brown alga Undaria pinnatifida from February to July, and C. japonica reproduced from July to September, a period during which the amphipods switch to a different host in July, the sporophytes of the saccharinan kelp S. j. var. ochotensis, where they stay until January. The amphipods then switched back to U. pinnatifida in January or February. Experimental evidence from a kelp-culturing facility also confirmed the timing of this host shift. The removal of U. pinnatifida from algal culture ropes in such facilities is suggested as a method to prevent amphipod damage, which is important for commercially farmed S. j. var. ochotensis.

In this study, we performed undrained cyclic–torsional–shear tests on clean and silty sands to examine post-liquefaction volumetric strain. Accordingly, we proposed a novel density index—ultimate volumetric strain—to evaluate the density of clean sand and silty soils; the proposed density index is based on soil compressibility. We discussed the test results with respect to relative density, skeleton void ratio, and ultimate volumetric strain. Consequently, we confirmed that ultimate volumetric strain showed good correlation with post-liquefaction volumetric strain irrespective of soil type, whereas values for relative density and skeleton void ratio were discordant. Further, we observed that, compared to maximum shear strain, accumulated shear strain was a better index for representing the effect of loading history. From these results therefore, we proposed a chart to evaluate post-liquefaction volumetric strain based on ultimate volumetric strain and accumulated shear strain.

Tumoral calcinosis (TC) refers to calcium salt deposition around large joints. It rarely affects the temporomandibular joint (TMJ), and only eight cases have been reported to date. We describe a case of TC in the left TMJ with resorption of the condyle and mandibular fossa. A 37-year-old woman complaining of malocclusion and a painless swelling around the left TMJ was referred to our hospital. The patient's medical history included Sjogren's syndrome and systemic sclerosis. Computed tomography and magnetic resonance imaging revealed calcification with a maximum diameter of 25 mm and resorption of the condyle and mandibular fossa. A clinical diagnosis of tophaceous pseudogout was made on the basis of these findings. The calcification was removed, and the TMJ was reconstructed under general anesthesia using a total TMJ replacement system. Pathological examination revealed TC. The patient was considered to have secondary TC based on the patient's medical history and results of additional blood tests. At six months post-operation, the patient had stable occlusion without TC recurrence.

Radiation esophagitis requiring endoscopic evaluation occurs quite rarely, affecting

Abstract Detailed morphology of the first three postembryonic developmental stages (Stages I-III juvenile) in representatives from all four crayfish families, Austropotamobius torrentium (von Paula Schrank, 1803) (Astacidae), Procambarus virginalis Lyko, 2017 (Cambaridae), Cambaroides japonicus (De Haan, 1841 [in De Haan, 1833-1850]) (Cambaroididae) and Cherax destructor Clark, 1936 (Parastacidae) are described and the diagnostic characters for each family are indicated. A phylogenetic tree of freshwater Astacidea, based on these new diagnostic juvenile characters is constructed to suborder, superfamily and family levels, and compared with a molecular phylogenetic tree. The evolutionary history of maternal care in freshwater crayfish is discussed based on particular features of the postembryonic stages of each family. Using comparisons between the phylogenetic tree and global geo-history, the location and timing of the early evolution of maternal care in postembryonic development and the extension of this care are estimated.

Myxoma is a benign tumor of mesenchymal origin. It frequently occurs in the muscles of the hip and extremities; however, it rarely occurs in the head and neck region. This report describes the second case of an intramuscular myxoma of the tongue. A 23-year-old woman was referred to our institution for the diagnosis and treatment of a left tongue lesion. T2-weighted magnetic resonance imaging revealed an 8×6-mm mass in the tongue. Based on a clinical diagnosis of a tongue tumor, excisional biopsy was performed under general anesthesia. The histopathological diagnosis was an intramuscular myxoma. The postoperative course was uneventful, and there was no evidence of tumor recurrence 3 years after surgery.

Osteosarcoma is a malignant tumor in which the cancerous cells produce an osteoid matrix or mineralized bone. Jaw bones are affected in 6% of all osteosarcomas and are the fourth most common site of origin. Surgical treatment of osteosarcoma in elderly patients is rarely reported. Here, we report successful treatment of osteosarcoma arising in the mandible of a 90-year-old man. The patient was referred to our institution for diagnosis and treatment of an oral lesion. Intraoral examination revealed that a hard mass measuring 35×27 mm was located on the floor of the oral cavity, attached to the bone, and its growth displaced the tongue posteriorly. Therefore, he experienced difficulty in speech and swallowing. Biopsy of the mandibular mass was suspicious for chondrosarcoma. Preoperative examination did not detect critical risks for general anesthesia or surgery. Based on a clinical diagnosis of a malignant bone tumor of the mandible, segmental mandibular resection with reconstruction using a titanium plate was performed. Surgical site infection occurred on postoperative day 12, which was resolved by drainage, local irrigation, and administration of antibiotics. There was no delirium or cardiovascular or pulmonary complications. Surgery resolved the patient’s difficulties in speech and swallowing. There was no evidence of tumor recurrence or metastasis 4 years after surgery. This case showed that it was not necessary to exclude surgical treatment merely because the patient was 90 years old. Indications for surgery should be determined individually to improve the patient’s quality of life.

Cranial bone defects are a major issue in the field of neurosurgery, and improper management of such defects can cause cosmetic issues as well as more serious infections and inflammation. Several strategies exist to manage these defects clinically, but most rely on synthetic materials that are prone to complications; thus, a bone regenerative approach would be superior. We tested a material (octacalcium phosphate collagen composite [OCP/Col]) that is known to enhance bone regeneration in a skull defect model in rats. Using a critical-sized rat skull defect model, OCP/Col was implanted in rats with an intact dura or with a partial defect of the dura. The results were compared with those in a no-treatment group over the course of 12 weeks using computed tomographic and histological analysis. OCP/Col enhanced bone regeneration, regardless of whether there was a defect of the dura. OCP/Col can be used to treat skull defects, even when the dura is injured or removed surgically, via bone regeneration with enhanced resorption of OCP/Col, thus limiting the risk of infection greatly.

Octacalcium phosphate and its collagen composite have been recognized as bone substitute materials possessing osteoconductivity and biodegradation properties. We evaluated the effectiveness of octacalcium phosphate and its collagen composite used for bone augmentation in major oral and maxillofacial surgeries in a clinical trial. Octacalcium phosphate and its collagen composite were used in cases of sinus floor elevation in 1- and 2-stage, socket preservation, cyst, and alveolar cleft procedures. A total of 60 patients were evaluated for effectiveness after the implantation of octacalcium phosphate and its collagen composite. Although sinus floor elevation in 1-stage, cyst, and alveolar cleft cases met the criteria for the judgment of success, sinus floor elevation in 2-stage and socket preservation groups did not meet the criteria in the initial evaluation. However, an additional evaluation for reconfirmation revealed the effectiveness of octacalcium phosphate and its collagen composite in those groups, and all evaluation results ultimately indicated the success of this clinical trial. Therefore, this clinical trial suggested that application of octacalcium phosphate and its collagen composite for oral and maxillofacial surgery was safe and effective and that octacalcium phosphate and its collagen composite could be a bone substitute candidate instead of autologous bone.

Abstract Until recently, three subspecies had traditionally been recognized in the astacid species Pacifastacus leniusculus (Dana, 1852): Pacifastacus leniusculus leniusculus, Pacifastacus leniusculus klamathensis (Stimpson, 1857), and Pacifastacus leniusculus trowbridgii (Stimpson, 1857). The type specimens attributed to these taxa were re-described with detailed illustrations of taxonomic characteristics for further taxonomic works.

Global introductions of aquatic species and their associated pathogens are threatening worldwide biodiversity. The introduction of two North American crayfish species, Procambarus clarkii and Pacifastacus leniusculus, into Japan in 1927 seems to have negatively affected native Japanese crayfish populations of Cambaroides japonicus. Several studies have shown the decline of these native populations due to competition, predation and habitat colonization by the two invasive North American crayfish species. Here, we identify an additional factor contributing to this decline. We report the first crayfish plague outbreaks in C. japonicus populations in Japan, which were diagnosed using both histological and molecular approaches (analyses of the internal transcribed spacer region). Subsequent analyses of the mitochondrial ribosomal rnnS and rnnL regions of diseased specimens indicate that these outbreaks originated from a P. clarkii population and identify a novel haplotype of Aphanomyces astaci, d3-haplotype, hosted by P. clarkii. Overall, our findings demonstrate the first two cases of crayfish plague in Japan, and the first case in a non-European native crayfish species, which originated from the red swamp crayfish P. clarkii. This finding is a matter of concern for the conservation of the native freshwater species of Japan and also highlights the risk of introducing crayfish carrier species into biogeographic regions harboring species susceptible to the crayfish plague.

It was demonstrated that octacalcium phosphate collagen composite achieved notable bone regeneration in bone defects in preclinical studies. On the basis of the research results, an investigator-initiated exploratory clinical trial was conducted after approval from a local Institutional Review Board. This clinical study was performed as a single-arm non-randomized intervention study. Octacalcium phosphate collagen composite was implanted into a total of 10 cases of alveolar bone defects after tooth extractions and cystectomy. Safety assessment was performed in terms of the clinical course and several consecutive laboratory examinations, and sequential radiographs were used for efficacy assessment. All participants uneventfully completed the clinical trial without major problems in their general condition. Postoperative wound swelling was observed, as also commonly seen in tooth extraction or cystectomy. Although no serious liver dysfunction, renal dysfunction, electrolyte imbalance, or abnormal urinalysis results were recognized, the number of white blood cells and C-reactive protein level temporarily increased after the operation. An increase in radiopacity in the octacalcium phosphate collagen composite–implanted site was observed in all cases. Finally, the border between the original bone and the octacalcium phosphate collagen composite–implanted site became indistinguishable. These results suggest that octacalcium phosphate collagen composite could be utilized safely in clinical situations in the future.

Intra-specific genetic diversity is important not only because it influences population persistence and evolutionary potential, but also because it contains past geological, climatic and environmental information. In this paper, we show unusually clear genetic structure of the endangered Japanese crayfish that, as a sedentary species, provides many insights into lesser-known past environments in northern Japan. Over the native range, most populations consisted of unique 16S mtDNA haplotypes, resulting in significant genetic divergence (overall F(ST) = 0.96). Owing to the simple and clear structure, a new graphic approach unraveled a detailed evolutionary history; regional crayfish populations were comprised of two distinct lineages that had experienced contrasting demographic processes (i.e. rapid expansion vs. slow stepwise range expansion) following differential drainage topologies and past climate events. Nuclear DNA sequences also showed deep separation between the lineages. Current ocean barriers to dispersal did not significantly affect the genetic structure of the freshwater crayfish, indicating the formation of relatively recent land bridges. This study provides one of the best examples of how phylogeographic analysis can unravel a detailed evolutionary history of a species and how this history contributes to the understanding of the past environment in the region. Ongoing local extinctions of the crayfish lead not only to loss of biodiversity but also to the loss of a significant information regarding past geological and climatic events.

Recent studies suggest that relict communities of Saccharina japonica var. ochotensis are rarely observed in southwestern Hokkaido, where S. japonica. var. religiosa is generally distributed. Previous research has mainly focused on the morphology of these species, and field survey data is very limited. In the present study, relict S. japonica var. ochotensis communities were observed only near the estuaries of larger rivers, specifically in estuarine areas where bedrock is present and the seashore has a gentle gradient slope. The biomass and size (length, width, and weight) of annual and biennial relict S. japonica. var. ochotensis were recorded. The carbon/nitrogen ratio of the kelp sporophytes was analyzed, and relatively lower values were observed in the relict community of this species. This information may help in the maintenance of kelp beds in southwestern Hokkaido and the wise utilization of relict S. japonica var. ochotensis in the estuarine areas of southwestern Hokkaido, Sea of Japan. [ABSTRACT FROM AUTHOR]