Enabling Faster Locomotion of Planetary Rovers with a Mechanically-Hybrid Suspension

The exploration of the lunar poles and the collection of samples from the martian surface are characterized by shorter time windows demanding increased autonomy and speeds. Autonomous mobile robots must intrinsically cope with a wider range of disturbances. Faster off-road navigation has been explored for terrestrial applications but the combined effects of increased speeds and reduced gravity fields are yet to be fully studied. In this paper, we design and demonstrate a novel fully passive suspension design for wheeled planetary robots, which couples a high-range passive rocker with elastic in-wheel coil-over shock absorbers. The design was initially conceived and verified in a reduced-gravity (1.625 m/s$^2$) simulated environment, where three different passive suspension configurations were evaluated against a set of challenges--climbing steep slopes and surmounting unexpected obstacles like rocks and outcrops--and later prototyped and validated in a series of field tests. The proposed mechanically-hybrid suspension proves to mitigate more effectively the negative effects (high-frequency/high-amplitude vibrations and impact loads) of faster locomotion (>1 m/s) over unstructured terrains under varied gravity fields. This lowers the demand on navigation and control systems, impacting the efficiency of exploration missions in the years to come.Comment: 8 pages, 13 figure

Serum Autotaxin Is a Useful Disease Progression Marker in Patients with Primary Biliary Cholangitis

Autotaxin (ATX) is a secreted enzyme metabolized by liver sinusoidal endothelial cells that has been associated with liver fibrosis. We evaluated serum ATX values in 128 treatment-naive, histologically assessed primary biliary cholangitis (PBC) patients and 80 healthy controls for comparisons of clinical parameters in a case-control study. The median ATX concentrations in controls and PBC patients of Nakanuma's stage I, II, III, and IV were 0.70, 0.80, 0.87, 1.03, and 1.70 mg/L, respectively, which increased significantly with disease stage (r = 0.53, P < 0.0001) as confirmed by Scheuer's classification (r = 0.43, P < 0.0001). ATX correlated with Wisteria floribunda agglutinin-positive Mac-2 binding protein (M2BPGi) (r = 0.51, P < 0.0001) and fibrosis index based on four factors (FIB-4) index (r = 0.51, P < 0.0001). While ALP and M2BPGi levels had decreased significantly (both P < 0.001) by 12 months of ursodeoxycholic acid treatment, ATX had not (0.95 to 0.96 mg/L) (P = 0.07). We observed in a longitudinal study that ATX increased significantly (P < 0.00001) over 18 years in an independent group of 29 patients. Patients succumbing to disease-related death showed a significantly higher ATX increase rate (0.05 mg/L/year) than did survivors (0.02 mg/L/year) (P < 0.01). ATX therefore appears useful for assessing disease stage and prognosis in PBC.ArticleSCIENTIFIC REPORTS.8:8159(2018)journal articl

Impaired Maternal Behavior in Usp46 Mutant Mice: A Model for Trans-Generational Transmission of Maternal Care.

Usp46 mutant mice (congenic strain on a B6 genetic background; MT mice) have a low weaning rate and display poor maternal behavior compared to C57BL/6J mice (B6 mice). Based on these observations, we examined how maternal behavior is shaped by cross-fostering and in-fostering MT and B6 mice. The experiments consisted of six groups: B6 mice fostered by their biological mother (B6-CO); MT mice fostered by their biological mother (MT-CO); B6 mice fostered by a different B6 mother (B6-IF); MT mice fostered by a different MT mother (MT-IF); B6 mice fostered by an MT mother (B6-CF); and MT mice fostered by a B6 mother (MT-CF). Maternal behavior was assessed using the pup-retrieval test in adult female offspring, and four parameters, time nursing pups in the nest, time sniffing or licking pups, rearing behavior, and latency to retrieve pups, were measured. Cross-fostering significantly reduced time spent nursing and sniffing/licking pup, and increased the number of instances of rearing in the B6-CF group, and improved three parameters of maternal behaviors (nursing, rearing and latency) in the MT-CF group. These results indicate that the level of maternal care is transmitted to their pups and proper maternal behaviors can be shaped if adequate postpartum maternal care is given, even in genetically vulnerable mice. However, the offspring's genotype may also influence the development of maternal behaviors in adulthood. Thus, MT mice may prove useful as a model for trans-generational transmission of maternal care, and these findings may provide insight into the mechanisms of maltreating behaviors in human child abuse

Hepatic Angiosarcoma with Kasabach-Merritt Phenomenon: A Case Report and Review of the Literature

A 76-year-old woman was referred to our hospital due to massive gingival bleeding following teeth extraction. Laboratory findings suggested disseminated intravascular coagulopathy (DIC). Enhanced computed tomography and magnetic resonance imaging disclosed multiple hypervascular liver masses of 2-6 cm in diameter, the largest of which displaying an irregular enhancement pattern. We considered that her DIC was caused by the multiple liver masses and commenced repeated erythrocyte/fresh frozen plasma infusion and gabexate mesilate administration. However, the DIC proved uncontrollable and trans-arterial embolization could not be attempted. The patient eventually died 4 months after admission due to spontaneous hepatic tumor rupture and hepatic failure. Post-mortem hepatic tumor biopsy led to a final diagnosis of hepatic angiosarcoma with Kasabach-Merritt phenomenon (KMP). Among the 7 cases of hepatic angiosarcoma representing KMP found in the literature, mortality occurred within 4 months of the appearance of bleeding tendency primarily due to abdominal bleeding and hepatic failure. The possibility of hepatic angiosarcoma should be considered in patients with DIC and hypervascular liver tumors. Since treatment is uncertain and prognosis is poor, novel diagnostic and therapeutic advances are needed for angiosarcoma

Effects of <i>Usp46</i> mutation on rate of weaning. A: Number of pups in the uterus prior to parturition.

<p>B: Number of pups weaned at approximately 25 days after birth. The number of mice is shown within parentheses. **<i>p</i> < 0.01, Kruskal-Wallis one-way ANOVA.</p

Outline of fostering experiments. B6-CO: B6 mice fostered by their biological mother.

<p>B6-IF: B6 mice fostered by a different B6 mother. B6-CF: B6 mice fostered by an MT mother. MT-CO: MT mice fostered by their biological mother. MT-IF: MT mice fostered by a different MT mother. MT-CF: MT mice fostered by a B6 mother. Offspring were tested at 8–12 weeks of age.</p

Fostering effects on maternal behavior in MT mice.

<p>MT-CF showed significant improvements in time spent nursing, rearing and latency to retrieve 1^st pup. The number of mice used is shown within parentheses. *<i>p</i> < 0.05, one-way ANOVA with Tukey’s <i>post hoc</i> test.</p

Maternal behaviors post parturition.

<p>Maternal behaviors (arched-back nursing, nursing in prone position and licking/grooming) were observed for 3 days following parturition. The ratio of occurrence of these behaviors is shown as the percent of total observation time. The number of mice used is shown within parentheses. *<i>p</i> < 0.05, Mann-Whitney U test.</p

Protocol: Prospective observational study investigating the prevalence and clinical outcome of portopulmonary hypertension in Japanese patients with chronic liver disease.

BackgroundPortopulmonary hypertension (PoPH) is a subtype of the pulmonary arterial hypertension (PAH) associated with portal hypertension. There is a dissociation between the proportion of PoPH in PAH and that of PoPH in patients with liver cirrhosis, suggesting PoPH underdiagnosis and an incomplete understanding of this entity in the clinical setting. Specifically, real-world data in Japan is largely unknown as compared with in Europe and the United States. The present study aims to elucidate the prevalence and etiology of PoPH in Japanese patients with chronic liver disease.Methods and designIn this prospective, single-center, observational investigation of PoPH patients with chronic liver disease, a targeted 2,500 Japanese adult patients regularly visiting Shinshu University Hospital in Matsumoto, Japan, for chronic liver disease will complete a standardized questionnaire on the presence of PoPH symptoms. If the respondent has signs of possible PoPH, ultrasound echocardiography (UCG) will be performed as a primary screening. In the case that UCG findings indicate pulmonary hypertension, the patient will be referred to a cardiologist for further evaluation, whereby a definitive diagnosis PoPH can be made. PoPH prevalence and etiology will be investigated at the time of diagnosis. Afterwards, patients with PoPH will be followed for five years for determination of survival rate.DiscussionThis study will reveal the prevalence, etiology, and 5-year survival rate of PoPH in Japanese patients with chronic liver disease.Trial registrationThis study is being performed at Shinshu University following registration as UMIN 000042287 on October 29, 2020

Changes in serum levels of autotaxin with direct-acting antiviral therapy in patients with chronic hepatitis C.

Sustained virological response (SVR) rates have increased remarkably since the introduction of direct-acting antiviral agents (DAAs) for chronic hepatitis C. Autotaxin (ATX) is a secreted enzyme converting lysophosphatidylcholine to lysophosphatidic acid and a newly established biomarker for liver fibrosis. Interferon-free DAA regimens for chronic hepatitis C could improve liver stiffness in SVR patients according to several non-invasive evaluation methods, but the clinical response and significance of ATX in this context have not yet been defined. We therefore investigated sequential serum ATX levels at baseline, 4 weeks after the start of treatment, and 24 weeks after treatment in 159 hepatitis C virus (HCV)-infected patients who received DAA therapy. Other non-invasive fibrosis markers (aspartate aminotransferase-to-platelet ratio and FIB-4 index) were examined as well. Baseline median ATX levels were comparable between the 144 patients who achieved a SVR and the 15 who did not (1.54 vs. 1.62 mg/L), but median ATX levels became significantly decreased during and after DAA therapy in the SVR group only (from 1.54 to 1.40 and 1.31 mg/L, respectively; P < 0.001). ATX was significantly decreased between baseline and 4 weeks of treatment in overall, male, and female SVR patients (all P < 0.001). In subjects with low necroinflammatory activity in the liver (i.e., alanine aminotransferase < 30 U/L), ATX levels were significantly reduced from baseline to 4 weeks of treatment and remained low (P < 0.001) in patients with a SVR. Thus, interferon-free DAA therapy was associated with a significant decrease in serum ATX levels in patients achieving a SVR, suggesting early regression of liver fibrosis in addition to inflammation treatment