Ocean acidification alters properties of the exoskeleton in adult Tanner crabs, Chionoecetes bairdi.

Ocean acidification can affect the ability of calcifying organisms to build and maintain mineralized tissue. In decapod crustaceans, the exoskeleton is a multilayered structure composed of chitin, protein and mineral, predominately magnesian calcite or amorphous calcium carbonate (ACC). We investigated the effects of acidification on the exoskeleton of mature (post-terminal-molt) female southern Tanner crabs, Chionoecetes bairdi Crabs were exposed to one of three pH levels - 8.1, 7.8 or 7.5 - for 2 years. Reduced pH led to a suite of body region-specific effects on the exoskeleton. Microhardness of the claw was 38% lower in crabs at pH 7.5 compared with those at pH 8.1, but carapace microhardness was unaffected by pH. In contrast, reduced pH altered elemental content in the carapace (reduced calcium, increased magnesium), but not the claw. Diminished structural integrity and thinning of the exoskeleton were observed at reduced pH in both body regions; internal erosion of the carapace was present in most crabs at pH 7.5, and the claws of these crabs showed substantial external erosion, with tooth-like denticles nearly or completely worn away. Using infrared spectroscopy, we observed a shift in the phase of calcium carbonate present in the carapace of pH 7.5 crabs: a mix of ACC and calcite was found in the carapace of crabs at pH 8.1, whereas the bulk of calcium carbonate had transformed to calcite in pH 7.5 crabs. With limited capacity for repair, the exoskeleton of long-lived crabs that undergo a terminal molt, such as C. bairdi, may be especially susceptible to ocean acidification.

Estrogen-related receptor participates in regulating glycolysis and influences embryonic development in silkworm Bombyx mori.

Estrogen-related receptors (ERRs) play indispensable roles in development, energy metabolism, and cancers and are metabolic switches in Drosophila. However, the mechanism underlying their metabolic role is unknown in insects. This study analysed the expression profiles of Bombyx mori ERR (BmERR), hexokinase (BmHK), pyruvate kinase (BmPK) and phosphofructokinase (BmPFK) during embryonic development. The expression of BmERR tended to be similar to that of the other genes. We observed a regulatory association between BmERR and glycolytic rate-limiting enzymes by BmERR overexpression, RNA interference (RNAi), and ERR inhibitors in B. mori embryo cells. Subsequently, ERR cis-regulation elements (ERREs) were predicted and identified in the BmPFK promoter. Transfection assays, electrophoretic mobility shift assays and chromatin immunoprecipitation showed that BmERR can bind to one of these elements to regulate the expression of BmPFK. ERREs were also predicted in the BmHK and BmPK promoters. In the eggs, the expression of glycolytic rate-limiting enzyme genes was suppressed when the expression of BmERR was interference by double-stranded BmERR, the glucose levels also was increased. Meanwhile, the development of silkworm embryos was delayed by about 1 day. These results indicate that BmERR can bind to the ERREs of glycolytic gene promoters and regulate the expression of glycolytic genes, ultimately affecting embryonic development in silkworms.

Rapid assessment of management options for promoting stock rebuilding in data-poor species under climate change.

The development of species recovery plans requires considering likely outcomes of different management interventions, but the complicating effects of climate change are rarely evaluated. We examined how qualitative network models (QNMs) can be deployed to support decision making when data, time, and funding limitations restrict use of more demanding quantitative methods. We used QNMs to evaluate management interventions intended to promote the rebuilding of a collapsed stock of blue king crab (Paralithodes platypus) (BKC) around the Pribilof Islands (eastern Bering Sea) to determine how their potential efficacy may change under climate change. Based on stakeholder input and a literature review, we constructed a QNM that described the life cycle of BKC, key ecological interactions, potential climate-change impacts, relative interaction strengths, and uncertainty in terms of interaction strengths and link presence. We performed sensitivity analyses to identify key sources of prediction uncertainty. Under a scenario of no climate change, predicted increases in BKC were reliable only when stock enhancement was implemented in a BKC hatchery-program scenario. However, when climate change was accounted for, the intervention could not counteract its adverse impacts, which had an overall negative effect on BKC. The remaining management scenarios related to changes in fishing effort on BKC predators. For those scenarios, BKC outcomes were unreliable, but climate change further decreased the probability of observing recovery. Including information on relative interaction strengths increased the likelihood of predicting positive outcomes for BKC approximately 5-50% under the management scenarios. The largest gains in prediction precision will be made by reducing uncertainty associated with ecological interactions between adult BKC and red king crab (Paralithodes camtschaticus). Qualitative network models are useful options when data are limited, but they remain underutilized in conservation.

Evaluación Rápida de las Opciones de Manejo para la Promoción de la Recuperación de Especies con Deficiencia de Datos bajo el Cambio Climático Resumen El desarrollo de los planes de recuperación de especies requiere de la consideración de los resultados probables de las diferentes intervenciones de manejo, pero los efectos agravantes del cambio climático rara vez están incluidos en esta evaluación. Examinamos cómo los modelos cualitativos de redes (QNMs) pueden implementarse para apoyar la toma de decisiones cuando los datos, el tiempo y el financiamiento sufren limitaciones que restringen el uso de métodos cuantitativos más demandantes. Usamos los QNMs para evaluar las intervenciones de manejo con la intención de promover el repoblamiento del colapsado cangrejo rey azul (Paralithodes platypus) (BKC) alrededor de las islas Pribilof (oriente del Mar de Bering) y así determinar cómo su eficiencia potencial puede modificarse bajo el cambio climático. Con base en aportaciones de los grupos de interés y una revisión bibliográfica construimos una QNM que describía el ciclo de vida del BKC, sus interacciones ecológicas importantes, impactos potenciales del cambio climático, fortalezas relativas de interacción, y la incertidumbre en relación con las fortalezas de interacción y la presencia de vínculos. Realizamos análisis de sensibilidad para identificar las fuentes clave de incertidumbre en la predicción. Bajo un escenario de ausencia de cambio climático, los incrementos pronosticados en la población de BKC fueron confiables solamente cuando el reforzamiento de la población se realizó en un escenario de programa de cultivo de BKC. Sin embargo, cuando se incluyó el cambio climático, la intervención de conservación no pudo contrarrestar los impactos adversos del cambio climático, lo cual tuvo un efecto negativo generalizado sobre los BKC. Los escenarios de manejo restantes estuvieron relacionados con los cambios en los esfuerzos de pesca sobre los depredadores del BKC. Para los estos últimos escenarios, los resultados de la población de BKC no fueron confiables, pero el cambio climático disminuyó todavía más la probabilidad de observar una recuperación. La inclusión de información sobre las fortalezas relativas de interacción incrementó la posibilidad de predecir los resultados de la población de BKC en ∼ 5 - 50% bajo los escenarios de manejo. Las mayores ganancias en la precisión de la predicción se lograrán reduciendo la incertidumbre asociada con las interacciones ecológicas entre los BKC adultos y el cangrejo rey rojo (Paralithodes camtschaticus). Los modelos cualitativos de redes son opciones útiles cuando los datos son limitados, pero permanecen subutilizados en la conservación.

Differentiating minimally invasive and invasive adenocarcinomas in patients with solitary sub-solid pulmonary nodules with a radiomics nomogram.

AIM: To evaluate the preoperative differentiation between the minimally invasive adenocarcinoma (MIA) and invasive adenocarcinoma (IAC) in patients with sub-solid pulmonary nodules using a radiomics nomogram. MATERIALS AND METHODS: A total of 100 patients with sub-solid pulmonary nodules who had pathologically confirmed MIA (43 patients, 13 male and 30 female) or IAC (57 patients, 26 male and 31 female) were recruited retrospectively. Radiomics features were extracted from computed tomography (CT) images. A radiomics signature was constructed by the least absolute shrinkage and selection operator (LASSO) algorithm. Solid presence, lesion size, shape regularity, and margins of pulmonary nodules were assessed to construct a subjective finding model. An integrated model of radiomics signatures and CT-based subjective findings, which was presented as a radiomics nomogram, was developed based on a multivariate logistic regression. The nomogram performance was assessed by its calibration, discrimination, and clinical usefulness. RESULTS: The radiomics signature, which consisted of 11 radiomics features, showed good discrimination accuracy. The radiomics nomogram showed good calibration and discrimination in the training set (AUC [area under the curve] 0.943; 95% confidence interval [CI]: 0.895-0.991) and validation set (AUC 0.912; 95% CI: 0.780-1.000). The radiomics nomogram was determined to be clinically useful in the decision curve analysis (DCA). CONCLUSION: The proposed radiomics nomogram has the potential to preoperatively differentiate MIA and IAC in patients with sub-solid pulmonary nodules.

Analysis of Characteristics and Relevant Factors of 1 340 Cases of Intentional Injury Cases in Southwest China.

ABSTRACT: Objective To investigate the characteristics and patterns of factors such as victims' information, injury tools and time of occurrence of intentional injury cases in southwest China. Methods One thousand three hundred and forty intentional injury cases from several places in southwest China from 2014 to 2016 assessed as minor injury level Ⅱ and above had been randomly selected. Data on victims' information, motives, injury tools, sites of occurrence, time of occurrence, injured parts and degrees of injury were classified and gathered, and then association analyses of motives and types of injury tools as well as degrees of injury and injury tools were made. Results Most of the victims were young adults between 20-50 years （65.2%）, male （82.3%）, rural household registration （62.8%）; the motives were mainly dispute （45.8%）. Injury tools were mostly blunt （54.6%） or sharp （36.0%）. Specifically, injuries were mostly made bare-handed （36.9%） and by cutting tools （33.2%）; the cases mainly occurred in public areas （59.0%）. Cases occurred more frequently in January （11.3%）, February （13.1%）, March （11.6%） and from 22：00 to 01：00 every night. Injuries mainly involved the craniofacial region. The wounds were mainly assessed as minor injury level Ⅱ （61.6%）. There was statistical significance in the difference of types of injury tools among cases with different motives （P<0.05）. There was statistical significance in the difference of the distribution of injury tools among cases with different degrees of injury （P<0.05）. Conclusion The occurrence of intentional injury cases in southwest China has potential patterns and relevant influencing factors. Prevention and analysis of such cases need to be comprehensively considered from the aspects such as victims' information, injury tools and time of occurrence.

[The role of hexokinase 2 in the metastasis of hepatocellular carcinoma cells].

Objective: To investigate the regulatory role of HK2 in the metastasis of hepatocellular carcinoma (HCC). Methods: The protein expressions of HK2 in 73 HCC tumor tissues and paired adjacent non-tumor tissues were evaluated by using immunohistochemical analysis. The scratch wound healing assay and Transwell assay had been used to analyze the migration and invasion of HCC cells with HK2 knockdown. Expressions of epithelial-to-mesenchymal transition (EMT)markers, such as E-cadherin, ZO-1, N-cadherin and vimentin, in HCC cells with HK2 knockdown were determined by qRT-PCR and Western blot analysis. Results: The expression levels of HK2 in tumor tissues and adjacent non-tumor tissues were 5.39±3.40 and 2.16±1.55, respectively. The protein expression of HK2 was significantly higher in tumor tissues compared with adjacent non-tumor tissues of HCC (P<0.05). Knockdown of HK2 in HCC cells decreased the cell motility from 1.00±0.54 to 0.56±0.09 (P<0.05), andknockdown of HK2 in HCC cells decreased the number of invaded cells form 345±42 to 215±34 (P<0.05). The expression of epithelial markers ZO-1 and E-cadherin were up-regulated, while mesenchymal markers vimentin and N-cadherin were down-regulated in HCC cells when HK2 was knockeddown. Conclusions: HK2 is up-regulated in HCC and promotes cell motility by stimulating EMT.

The impact of posttraumatic stress disorder on cannabis quit success.

BACKGROUND: Though a growing number of US Veterans are being diagnosed with cannabis use disorders, with posttraumatic stress disorder (PTSD) observed as the most frequently co-occurring psychiatric disorder among this population, no research has investigated the impact of PTSD diagnosis on cannabis quit success. OBJECTIVES: The present study sought to determine the impact of PTSD on cannabis use following a self-guided quit attempt. METHODS: Participants included 104, primarily male, cannabis-dependent US Veterans (Mage = 50.90 years, SDage = 9.90). The study design was prospective and included an assessment immediately prior to the quit attempt, and assessments weekly for the first 4 weeks post-quit, and then monthly through 6 months post-quit. RESULTS: Results indicated that PTSD diagnosis was not associated with time to first lapse or relapse. However, individuals with PTSD used more cannabis at baseline and evidenced a slower initial decline in cannabis use immediately following the quit attempt. All findings were significant after accounting for alcohol and tobacco use across the cessation period, as well as co-occurring mood and anxiety disorder diagnoses. CONCLUSION: Findings highlight the potential utility of interventions for individuals with cannabis use disorder and co-occurring PTSD, particularly early in a cessation attempt.

Modeling and forecasting the distribution of Vibrio vulnificus in Chesapeake Bay.

AIM: To construct statistical models to predict the presence, abundance and potential virulence of Vibrio vulnificus in surface waters of Chesapeake Bay for implementation in ecological forecasting systems. METHODS AND RESULTS: We evaluated and applied previously published qPCR assays to water samples (n = 1636) collected from Chesapeake Bay from 2007-2010 in conjunction with State water quality monitoring programmes. A variety of statistical techniques were used in concert to identify water quality parameters associated with V. vulnificus presence, abundance and virulence markers in the interest of developing strong predictive models for use in regional oceanographic modeling systems. A suite of models are provided to represent the best model fit and alternatives using environmental variables that allow them to be put to immediate use in current ecological forecasting efforts. CONCLUSIONS: Environmental parameters such as temperature, salinity and turbidity are capable of accurately predicting abundance and distribution of V. vulnificus in Chesapeake Bay. Forcing these empirical models with output from ocean modeling systems allows for spatially explicit forecasts for up to 48 h in the future. SIGNIFICANCE AND IMPACT OF THE STUDY: This study uses one of the largest data sets compiled to model Vibrio in an estuary, enhances our understanding of environmental correlates with abundance, distribution and presence of potentially virulent strains and offers a method to forecast these pathogens that may be replicated in other regions.

Work addiction in Chinese white-collar workers: the psychometric properties of its measure and its comorbidity with general anxiety in network analysis.

BACKGROUND: Work addiction (WA) threatens occupation-related health in many countries including China. This research aims to evaluate the psychometric properties of the Chinese version of Bergen Work Addiction Scale (BWAS), the most common measure of WA, to facilitate relevant studies in Chinese workers. A network analysis was further conducted to identify central and bridge symptoms within the WA-anxiety network to improve intervention practices. METHODS: A total of 694 Chinese white-collar workers completed an online questionnaire survey in March of 2022, and the responses to BWAS from a subsample of 50 participants one month after this survey were also collected. RESULTS: The unidimensionality of BWAS was supported by results of exploratory factor analysis, exploratory graph analysis, and confirmatory factor analysis and we found satisfactory internal consistency and acceptable test-retest reliability. Multiple-group factor analyses confirmed the measurement invariance of BWAS across genders, districts (i.e., central China, eastern China, western China, and northeastern China), and age groups (i.e., young and middle-aged adults) while the convergent validity of BWAS was demonstrated by its significant correlations with Dutch Work Addiction Scale (r = 0.62, p < 0.001) and its criterion validity was indicated by its significant correlations with general anxiety, weekly work hours, and health status (r = -0.16 to 0.31, p < 0.001-0.01). Network analysis further revealed two central symptoms (WA-tolerance and WA-problems) and three bridge symptoms (WA-problems, WA-mood modification, and mouth dryness of general anxiety) maintaining the WA-anxiety comorbidity. CONCLUSIONS: Our findings suggest that BWAS is a valid measure of WA in Chinese workers and interventions should put special attention to the identified central and bridge symptoms underlying the WA-anxiety network.

Work hard and sleep better: Work autonomy attenuates the longitudinal effect of workaholism on sleep problem among Chinese working adults.

The prevalence of workaholism has negative consequences on human health. Lack of sleep, a well-known problem among adults in modern society, is often attributed to overwork as a result of workaholism. Yet there is a lack of empirical research examining how and when workaholism will lead to sleep problems. To answer this question and to examine the longitudinal effect of workaholism on sleep in China, we investigate the mediating role of perceived evening responsibilities of work and the moderating effect of work autonomy. Two hundred and five Chinese working adults (58.0% female) voluntarily completed the online questionnaires at Time 1 (T1) and Time 2 (T2; 1-month later). Results showed that workaholism at T1 had a significant and positive correlation with sleep problem at T2. Further analysis suggested that perceived evening responsibilities of work fully mediated the relationship between workaholism and sleep problem. Work autonomy was shown to buffer the positive effect of workaholism on perceived evening responsibilities of work and attenuate the indirect effect of workaholism on sleep problem. While workers should be made aware of the negative impact of workaholism on sleep, organizations should also consider interventions to enhance employees' autonomy and control of their work.

Recovery Experiences Protect Emotionally Exhausted White-Collar Workers from Gaming Addiction.

Gaming addiction and its negative consequences have attracted public concern, but relatively little is known regarding its impact on adult workers. This study aims to test the association between gaming addiction and emotional exhaustion as well as the protective effect of recovery experiences on such an association among white-collar workers. We recruited 205 working adults (female = 58%) who voluntarily completed an online questionnaire. The results showed that male and younger workers were more vulnerable to gaming addiction. Emotional exhaustion was significantly and positively associated, while two (i.e., relaxation and control) of the four recovery experiences were negatively correlated with gaming addiction. Control experience had an indirect effect on gaming addiction via emotional exhaustion. Moreover, relaxation experience buffered the risk effect of emotional exhaustion on gaming addiction so that the effect is less pronounced at high levels of relaxation. Interventions are suggested to raise workers' awareness of effective recovery experiences (especially for control and relaxation) and to facilitate their recovery opportunities.

A cross-lagged panel model for testing the bidirectional relationship between depression and smartphone addiction and the influences of maladaptive metacognition on them in Chinese adolescents.

AIMS: Despite the high prevalence of both depression and smartphone addiction among Chinese adolescents, research examining their bidirectional relationship has been limited. Moreover, longitudinal research regarding the influence of maladaptive metacognitive beliefs on smartphone addiction is scarce. This 6-month longitudinal study aimed to address these research gaps by testing a cross-lagged panel model of maladaptive metacognition, depression, and smartphone addiction. METHODS: Four hundred and fifty-nine Chinese high school students voluntarily completed an anonymous questionnaire at baseline, and 313 of them (36.1% male; age = 14 to 18; M = 16.88, SD = 0.62) completed the same questionnaire at follow-up. RESULTS: Positive correlations were shown among depression, smartphone addiction, and maladaptive metacognition at both waves (r = 0.16 to 0.57, p < .01). The results of the cross-lagged analysis demonstrated only the prospective effect of depression on smartphone addiction (ß = 0.18, p < .001) but not vice versa. Moreover, maladaptive metacognition assessed at baseline significantly predicted subsequent depression (ß = 0.14, p < .01) but not smartphone addiction (p>.05). Additional path analysis showed a significant indirect effect of baseline maladaptive metacognition (0.099 [95% CI = 0.042, 0.183]) on subsequent smartphone addiction, via depression. CONCLUSIONS: Findings of this study showed that the relationship between depression and smartphone addiction was unidirectional rather than bidirectional among Chinese adolescents. Specifically, depression predicted smartphone addiction, while maladaptive metacognition predicted depression. Depression also mediated the relationship between maladaptive metacognition and smartphone addiction. The findings suggest that incorporating metacognition and depression interventions into smartphone addiction prevention designs for adolescents may be beneficial.

[Survey on tobacco use and associated factors in population in Shandong province, 2016-2017].

Objective: To understand the status of tobacco use and related influencing factors in population in Shandong province. Methods: Stratified multi-stage cluster sampling was used to select respondents from 216 villages (communities) of 36 districts (counties) in Shandong province. Influencing factors on smoking were analyzed by logistic regression model. Results: The adequate sample size was 6 271 participants. After complex weighted, the current smoking prevalence was 23.93%,45.58% in males and 1.18% in females. The Public's smoking rates varied widely among different groups in the population. 45-64 age group had the highest smoking rate (25.07%). Smoking rates were substantially different in education levels, with the highest in junior high school (28.94%). The rate was higher in the rural area (24.98%) than that in the urban areas (23.08%). The average daily smoking rate was 20.23%. The average age of initiating smoking was 21.21 years. The average daily cigarette intake was 16.31 cigarettes. Among all the former and current smokers, the quitting rate was 20.79%. Multiple logistic regression model analysis showed that gender, age, occupation, region, and health knowledge score were correlated with smoking behavior. The current smoking rate of men was much higher than that of women (OR=49.625, 95%CI: 37.832-65.093). The current smoking rate in 45-64 age group was higher than that in the 15-24 age group (OR=1.830, 95%CI: 1.048-3.194). The current smoking rate of medical (OR=0.403, 95%CI: 0.187-0.866) and retired personnel (OR=0.648, 95%CI: 0.481-0.873) were lower than those engaging in agriculture, forestry, animal husbandry and the fishery ,respectively. The prevalence of residents living in the central part showed lower rate on current smoking than that in the eastern region (OR=0.724, 95%CI: 0.606-0.865). The current smoking prevalence of smoke hazard in 1-3 score group was higher than that in the group with 4-6 score (OR=1.432, 95%CI: 1.240-1.654). Conclusions: Smoking rate in adults in Shandong remained stable and at a high level. Comprehensive intervention measures such as tobacco control and health education should be carried out to reduce the smoking rate.

Mechanical Resistance in Decapod Claw Denticles: Contribution of Structure and Composition.

The decapod crustacean exoskeleton is a multi-layered structure composed of chitin-protein fibers embedded with calcium salts. Decapod claws display tooth-like denticles, which come into direct contact with predators and prey. They are subjected to more regular and intense mechanical stress than other parts of the exoskeleton and therefore must be especially resistant to wear and abrasion. Here, we characterized denticle properties in five decapod species. Dactyls from three brachyuran crabs (Cancer borealis, Callinectes sapidus, and Chionoecetes opilio) and two anomuran crabs (Paralomis birsteini and Paralithodes camtschaticus) were sectioned normal to the contact surface of the denticle, revealing the interior of the denticle and the bulk endocuticle in which it is embedded. Microhardness, micro- and ultrastructure, and elemental composition were assessed along a transect running the width of the cuticle using microindentation hardness testing, optical and scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS), respectively. In all species tested, hardness was dramatically higher-up to ten times-in the denticle than in the bulk endocuticle. Likewise, in all species there was an increase in packing density of mineralized chitin-protein fibers, a decrease in width of the pore canals that run through the cuticle, and a decrease in phosphorous content from endocuticle to denticle. The changes in hardness across the cuticle, and the relationship between hardness, calcium, and magnesium content, however, varied among species. Although mechanical resistance of the denticles was exceptionally high in all species, the basis for resistance appears to differ among species. STATEMENT OF SIGNIFICANCE: Understanding the diverse mechanisms by which animals attain exceptionally high mechanical resistance may enable development of novel, biologically inspired materials. Decapod crustacean claws, and particularly the tooth-like denticles that these claws display, are of interest in this regard, as they must be especially resistant to wear. We assessed mechanical, elemental, and structural properties of the claw cuticle in five decapod species. Without exception, microhardness was dramatically higher in the denticle than in the bulk endocuticle. Multivariant statistical analyses, however, showed that the relationships among microhardness, elemental content, and structural variables differed among species. Such patterns likely result from strong evolutionary pressure on feeding and defensive structures and a trade-off between mechanical properties and energetic cost of exoskeleton formation.

Glutathione reductase in red blood cells: variant associated with gout.

A variant of red cell gluta thione reductase, characterized by greater electrophoretic mobility, in creased enzyme activity per unit of hemoglobin, and an autosomal mode of inheritance, has been found in Negro populations. There appears to be an association of this variant with primary gout.

Hydration rate of obsidian.

The hydration rates of 12 obsidian samples of different chemical compositions were measured at temperatures from 95 degrees to 245 degrees C. An expression relating hydration rate to temperature was derived for each sample. The SiO(2) content and refractive index are related to the hydration rate, as are the CaO, MgO, and original water contents. With this information it is possible to calculate the hydration rate of a sample from its silica content, refractive index, or chemical index and a knowledge of the effective temperature at which the hydration occurred. The effective hydration temperature can be either measured or approximated from weather records. Rates have been calculated by both methods, and the results show that weather records can give a good approximation to the true EHT, particularly in tropical and subtropical climates. If one determines the EHT by any of the methods suggested, and also measures or knows the rate of hydration of the particular obsidian used, it should be possible to carry out absolute dating to +/- 10 percent of the true age over periods as short as several years and as long as millions of years.

Obsidian hydration dates glacial loading?

Three different groups of hydration rinds have been measured on thin sections of obsidian from Obsidian Cliff, Yellowstone National Park, Wyoming. The average thickness of the thickest (oldest) group of hydration rinds is 16.3 micrometers and can be related to the original emplacement of the flow 176,000 years ago (potassium-argon age). In addition to these original surfaces, most thin sections show cracks and surfaces which have average hydration rind thicknesses of 14.5 and 7.9 micrometers. These later two hydration rinds compare closely in thickness with those on obsidian pebbles in the Bull Lake and Pinedale terminal moraines in the West Yellowstone Basin, which are 14 to 15 and 7 to 8 micrometers thick, respectively. The later cracks are thought to have been formed by glacial loading during the Bull Lake and Pinedale glaciations, when an estimated 800 meters of ice covered the Obsidian Cliff flow.

A comparative cytogenetic study of the rice (Oryza sativa L.) autotetraploid restorers and hybrids.

We studied pollen fertility, seed set and cytogenetic characteristics of restorer lines and F1 hybrids of autotetraploid rice. T4002, T4063, T461A x T4002 and T461A x T4063 showed significantly higher pollen fertility and seed set than T4132 and T461A x T4132. Meiotic pairing configurations of T4002, T4063, T4132, T461A x T4002, T461A x T4063 and T461A x T4132 were 0.051 + 19.96II (9.89 rod + 10.07 ring) + 0.01III + + 2.00IV, 0.11I + 19.17II (8.90 rod + 10.37 ring) + 0.09III + 2.26IV + 0.01VI, 1.34I + 9.46II (4.50 rod + 4.96 ring) + 0.80III + 6.02IV + 0.09VI + 0.09VIII, 0.02I + 14.36II (6.44 rod + 7.91 ring) + 0.01III + 4.80IV + 0.01VIII, 0.06I + 17.67II (11.01 rod + 6.67 ring) + 0.06III + 3.10IV + 0.01VI and 1.11I + 11.31II (5.80 rod + 5.51 ring) + 0.41III + 5.63IV + 0.03VI + 0.03VIII, respectively. Configuration 16II + 4IV and 12II + 6IV occurred in the highest frequency among the autotetraploid restorers and hybrids. Meiotic chromosome behaviors were less abnormal in the tetraploids with high seed set than those with low seed set. The hybrids had fewer frequencies of bivalents, univalents, trivalents and multivalents than the restorers, but higher frequency of quatrivalents than the restorers at MI. The frequency of univalents at MI had the most impact on pollen fertility and seed set, i.e., pollen fertility decreased with the increase of univalents. The secondary impact factors were trivalents and multivalents, and bivalents and quatrivalents had no effect on pollen fertility and seed set. The correlative relationship between pollen fertility and cytogenetic behaviors could be utilized to improve seed set in autotetraploidy breeding.

Can some early revision total hip arthroplasties be avoided?

AIMS: Studying the indications for revision total hip arthroplasty (THA) may enable surgeons to change their practice during the initial procedure, thereby reducing the need for revision surgery. The aim of this study was to identify and describe the potentially avoidable indications for revision THA within five years of the initial procedure. PATIENTS AND METHODS: A retrospective review of 117 patients (73 women, 44 men; mean age 61.5 years (27 to 88)) who met the inclusion criteria was conducted. Three adult reconstruction surgeons independently reviewed the radiographs and medical records, and they classified the revision THAs into two categories: potentially avoidable and unavoidable. Baseline demographics, perioperative details, and quality outcomes up to the last follow-up were recorded. RESULTS: A total of 60 revision THAs (51.3%) were deemed potentially avoidable and 57 (48.7%) were deemed unavoidable. The following were identified as avoidable factors: suboptimal positioning of the acetabular component (29; 48%), intraoperative fracture or a fracture missed on an intraoperative radiograph (20; 33%), early (less than two weeks) aseptic loosening (seven; 11.7%), and symptomatic leg length discrepancy of > 1 cm (four; 6.7%). CONCLUSION: A surprisingly large proportion of acute revision THAs are potentially avoidable. Surgeons must carefully evaluate the indications for revision THAs in their practice and identify new methods to address these issues. Cite this article: Bone Joint J 2019;101-B(6 Supple B):97-103.