bluuebunny/crossref_metadata_2025 huggingface dataset:
Histone Methylation: Achilles Heel and Powerful Mediator of Periodontal Homeostasis
Authors: Francis M. , Gopinathan G. , Foyle D. , Fallah P. , Gonzalez M. , Luan X. , Diekwisch T.G.H.
Published: August 2020

The packaging of DNA around nucleosomes exerts dynamic control over eukaryotic gene expression either by granting access to the transcriptional machinery in an open chromatin state or by silencing transcription via chromatin compaction. Histone methylation modification affects chromatin through the addition of methyl groups to lysine or arginine residues of histones H3 and H4 by means of histone methyl transferases or histone demethylases. Changes in histone methylation state modulate periodontal gene expression and have profound effects on periodontal development, health, and therapy. At the onset of periodontal development, progenitor cell populations such as dental follicle cells are characterized by an open H3K4me3 chromatin mark on RUNX2, MSX2, and DLX5 gene promoters. During further development, periodontal progenitor differentiation undergoes a global switch from the H3K4me3 active methyl mark to the H3K27me3 repressive mark. When compared with dental pulp cells, periodontal neural crest lineage differentiation is characterized by repressive H3K9me3 and H3K27me3 marks on typical dentinogenesis-related genes. Inflammatory conditions as they occur during periodontal disease result in unique histone methylation signatures in affected cell populations, including repressive H3K9me3 and H3K27me3 histone marks on extracellular matrix gene promoters and active H3K4me3 marks on interleukin, defensin, and chemokine gene promoters, facilitating a rapid inflammatory response to microbial pathogens. The inflammation-induced repression of chromatin on extracellular matrix gene promoters presents a therapeutic opportunity for the application of histone methylation inhibitors capable of inhibiting suppressive trimethylation marks. Furthermore, inhibition of chromatin coregulators through interference with key inflammatory mediators such as NF-kB by means of methyltransferase inhibitors provides another avenue to halt the exacerbation of the inflammatory response in periodontal tissues. In conclusion, histone methylation dynamics play an intricate role in the fine-tuning of chromatin states during periodontal development and harbor yet-to-be-realized potential for the treatment of periodontal disease.
Work-Family Conflict and Suicidal Ideation Among Physicians of Pakistan: The Moderating Role of Perceived Life Satisfaction
Authors: Akram Bushra , Bibi Bushra , Ashfaq Ahmed Mirza , Kausar Noreena
Published: August 2020

Recent studies have shown an increased level of suicidal behavior among physicians, not only in Pakistan but all over the world. In this cross-sectional study, 622 physicians, aged 32–55 years, participated from 50 private and public hospitals located in the seven cities of the Punjab province of Pakistan. Three standardized tools were used to assess suicidal ideation, perceived life satisfaction and work-family conflict of the participants. Results showed work-family conflict as positive whereas life satisfaction was shown to be a negative predictor of suicidal ideation among the physicians. Furthermore, findings suggested that, as a moderator, percieved life satisfaction holds a significant role in decreasing the levels of work-family conflict and suicidal ideation among the physicians. Therefore, it is recommendable to incoroporate a perceived life satisfaction enhancement program into the training of physicians so that suicidal ideation may be prevented and treated effectively.
Fear and Psychopathology During the COVID-19 Crisis: Neuroticism, Hypochondriasis, Reassurance-Seeking, and Coronaphobia as Fear Factors
Authors: Lee Sherman A. , Crunk Elizabeth A.
Published: August 2020

The COVID-19 pandemic has generated a rise in psychological distress worldwide. Although fear appears to be a major contributing factor, there has been no systematic research to determine which specific facets of fear predict psychopathology during the coronavirus crisis. The present study is the first to examine which fear factors uniquely predict clinical levels of depressive symptoms and generalized anxiety. Data were collected from 256 adults in the United States recruited from Amazon’s Mechanical Turk (MTurk) during the coronavirus pandemic. The results from logistic regression analyses demonstrated that neuroticism, coronaphobia, and hypochondriasis were fear factors that predicted pandemic-related psychopathology in adults. These findings suggest that mental health professionals should screen individuals for this set of fear factors when choosing appropriate assessments and interventions for treating people who are suffering during the crisis.
Validity and Reliability of the Interpersonal Behaviors Questionnaire in Physical Education With Spanish Secondary School Students
Authors: Burgueño Rafael , Medina-Casaubón Jesús
Published: August 2020

Grounded in Self-Determination Theory, the objective of this study was to adapt the Interpersonal Behaviors Questionnaire (IBQ) to the Spanish physical education (PE) context and to examine its psychometric properties using a sample of Spanish secondary school students. The participants were 478 secondary school students (220 boys and 258 girls; Mage = 14.56, SDage = 1.06) who received two 60-minute compulsory PE classes per week. A confirmatory factor analysis psychometrically underpinned a 24-item six-factor correlated model (i.e. autonomy, competence and relatedness supportive and autonomy, competence and relatedness thwarting behaviors) that was invariant across gender and age. A reliability examination found appropriate levels of internal consistency and temporal stability for the instrument’s six factors. A partial correlation analysis showed that while the three types of need-supportive behaviors from PE teachers were positively correlated with need satisfaction and autonomous motivation; the three types of need-thwarting behaviors from PE teachers were positively correlated with need frustration, controlled motivation and amotivation. Thus, this study showed that the Spanish version of the IBQ is valid and reliable for assessing PE students’ perceptions of the six specific types of interpersonal behavior that may be adopted by PE teachers.
Self-Esteem and Symptoms of Eating-Disordered Behavior Among Female Adolescents
Authors: Zamani Sani Seyed Hojjat , Fathirezaie Zahra , Gerber Markus , Pühse Uwe , Bahmani Dena Sadeghi , Bashiri Mahdi , Pourali Mohammad , Brand Serge
Published: August 2020

Background

Compared to males, female adolescents show greater concerns about their appearance, concerns related to their self-esteem. We explored the associations between self-esteem, body image and BMI as proxies for appearance, and eating-disordered behavior among adolescent females.

Methods

A total of 263 females (mean age:15.78 years) took part in this study. They completed questionnaires covering anthropometric characteristics, self-esteem, eating-disordered behavior, subjective physical activity levels, and body image.

Results

Higher scores for self-esteem were associated with higher scores for eating-disordered behavior, indices of physical activity, and slimmer body image. Body image was not associated with eating-disordered behavior. Multiple regression analyses showed that self-esteem, but not physical activity, or body image predicted eating-disordered behavior.

Conclusions

Among a non-clinical sample of female adolescents, self-esteem and eating-disordered behavior were positively associated. Body image was associated in a complex and contradictory fashion. It is possible that cognitive-emotional mastering of the vital impulse to eat may enhance self-esteem.
‘Near miss’ housing market response to the 2012 northern Italy earthquake: The role of housing quality and risk perception
Authors: Modica Marco , Zoboli Roberto , Meroni Fabrizio , Pessina Vera , Squarcina Thea , Locati Mario
Published: August 2020

This paper examines the housing market response to the earthquake that hit northern Italy in May 2012. The available literature shows that the average price of houses decreases after a disaster because of the potential underestimation of disaster risk by households, or because of a higher risk perception in reaction to the unforeseen emergency. The physical assessment of the earthquake damage scenario provided in this paper (the so-called macro-seismic approach), combined with a difference-in-difference model with a multi-valued treatment, is able to extrapolate indirect information on the subjective perception of risk. We provide evidence that differences in costs and risk perceptions of the earthquake arise at high levels of damage. Furthermore, we also provide evidence that building characteristics, as well as the state of maintenance of houses, play a relevant role for subjective risk assessment, even though this assessment may be not related to the effective capacity of the buildings to resist earthquakes.
Toward a New Phase of Guerrilla Warfare in Colombia? The Reconstitution of the FARC-EP in Perspective
Authors: Gutiérrez D. José Antonio
Published: August 2020

The August 2019 announcement by some top former commanders of the Fuerzas Armadas Revolucionarias de Colombia–Ejército del Pueblo guerrillas in Colombia that they were resuming armed struggle was a major shock after the peace agreement between the rebels and the Colombian government in 2016. It was the clearest symptom of the current crisis of the peace process. It was not, however, an unforeseeable development. The government had brazenly attacked the content and the spirit of the peace agreement, and the systematic murders of ex-combatants and social leaders remained unpunished. As a result, increasing numbers of ex-combatants had decided to resume armed struggle. To regard these groups as mere criminals underestimates the political content of their statements and overlooks the reasons for this growing phenomenon. An exploration of the causes of the growing FARC-EP dissidences sets the stage for a discussion of the likely scenarios for conflict and peace building in the middle term.

El anuncio de algunos ex comandantes de la guerrilla de las Fuerzas Armadas Revolucionarias de Colombia-Ejército del Pueblo en agosto de 2019 sobre su reanudación de la lucha armada causó gran conmoción después del acuerdo de paz de 2016 entre los rebeldes y el gobierno. Este fue el síntoma más claro de la actual crisis del proceso de paz, pero no se trató de un acontecimiento imprevisible. El gobierno ya había atacado descaradamente el contenido y espíritu los acuerdos, y los asesinatos sistemáticos de excombatientes y líderes sociales seguían impunes. Como resultado, un número cada vez mayor de excombatientes se decidían por reanudar la lucha armada. Considerar a estos grupos como meros delincuentes subestima el contenido político de sus declaraciones y pasa por alto las razones de este fenómeno creciente. Una exploración de las causas de las progresivas disidencias de las FARC-EP sienta las bases para una discusión sobre escenarios probables en torno la construcción tanto de conflictos como de la paz a mediano plazo.
The Index of Race-Related Stress-Brief: Further Validation, Cross-Validation, and Item Response Theory-Based Evidence
Authors: Chapman-Hilliard Collette , Abdullah Tahirah , Denton Ellen-ge , Holman Andrea , Awad Germine
Published: August 2020

The Index of Race-Related Stress-Brief (IRRS-B) is one of the most widely used measures to assess race-related stress among Black Americans. Despite a long history of use in research and clinical settings, there has been limited scholarship examining the factor structure of the IRRS-B. In this study, we evaluated the item functioning and structural performance of the IRRS-B scores in a nationally recruited sample of Black Americans using item response and confirmatory factor analyses. Item-level analyses illustrated that items on the IRRS-B, in general, tended to be most informative at moderate levels of the latent construct. The proposed three-factor structure yielded a comparable fit to the data in a validation and a cross-validation subsample but did not meet recommended cutoff values for adequate model fit. Findings are discussed in terms of the implications for future use of the IRRS-B in research and clinical contexts.
Fear of missing out (FoMO): A generational phenomenon or an individual difference?
Authors: Barry Christopher T. , Wong Megan Y.
Published: August 2020

Fear of missing out (FoMO) regarding activities within one’s social circle is a potential downside of the advent of social media and more rapid forms of communication. To examine potential generational or individual implications of FoMO, this study considered age cohort differences and self-perception correlates of FoMO. Participants were 419 individuals from throughout the U.S. who were members of 14- to 17-year-old, 24- to 27-year-old, 34- to 37-year-old, or 44- to 47-year-old cohorts. There were no cohort differences in overall FoMO, FoMO regarding close friends, or FoMO regarding family members. Across age cohorts, low self-esteem and loneliness were each associated with high levels of FoMO, particularly for individuals who were also engaged in relatively greater social media activity. Thus, the present findings indicate that FoMO concerning others’ activities may be particularly problematic for some individuals who are highly engaged with social media.
Bios, mythoi and women entrepreneurs: A Wynterian analysis of the intersectional impacts of the COVID-19 pandemic on self-employed women and women-owned businesses
Authors: Martinez Dy Angela , Jayawarna Dilani
Published: August 2020

Decolonial philosopher Sylvia Wynter theorises the human animal as formed by both bios and mythoi, or matter and meaning. This article adopts this ontological perspective to explore the effects of the COVID-19 crisis on UK self-employed women and women-owned businesses through an intersectional lens accounting for race, class and gender. We argue that unequal health outcomes from COVID-19 are not solely biological; rather, they are also the outcome of social inequalities. Drawing upon the Wynterian elaboration of Fanon’s work on sociogeny – the shaping of the embodied human experience by the norms of given society – to explain this phenomenon, we contend that the same inequalities emerging in health outcomes will be reflected in entrepreneurship and self-employment. Drawing on Labour Force Survey data for the past decade, we peer through the Wynterian prism of bios and mythoi to argue that marginalised entrepreneurs are likely to experience extreme precarity due to COVID-19 and so require targeted support.
The Relation Between Teachers’ Positive Behavior Support and Language Support
Authors: Cunningham Jennifer E. , Hemmeter Mary Louise , Kaiser Ann P.
Published: August 2020

The goal of this study was to extend what is known about factors that contribute to the language-learning environment in early childhood classrooms. Two primary research questions were addressed: (a) Are measures of teacher use of classroom-wide positive behavior intervention and support (PBIS) strategies associated with the quality of teacher language support? and (b) Do teachers who receive program-wide training in PBIS strategies differ in their language interactions with children in their classrooms compared with a control group? Findings were mixed and provide preliminary support for the hypothesis that a positive relationship exists between PBIS strategies and the language-learning environment of preschool classrooms. Teachers’ scores on a measure of PBIS strategies were a significant predictor of global ratings of language support. However, teachers who were enrolled in the program-wide PBIS training group did not score significantly higher than teachers in a control group at posttest.
Design and optimal control of a tiltrotor micro-aerial vehicle for efficient omnidirectional flight
Authors: Allenspach Mike , Bodie Karen , Brunner Maximilian , Rinsoz Luca , Taylor Zachary , Kamel Mina , Siegwart Roland , Nieto Juan
Published: August 2020

Omnidirectional micro-aerial vehicles (MAVs) are a growing field of research, with demonstrated advantages for aerial interaction and uninhibited observation. While systems with complete pose omnidirectionality and high hover efficiency have been developed independently, a robust system that combines the two has not been demonstrated to date. This paper presents the design and optimal control of a novel omnidirectional vehicle that can exert a wrench in any orientation while maintaining efficient flight configurations. The system design is motivated by the result of a morphology design optimization. A six-degree-of-freedom optimal controller is derived, with an actuator allocation approach that implements task prioritization, and is robust to singularities. Flight experiments demonstrate and verify the system’s capabilities.
Assessment of cardiac and liver iron overload by magnetic resonance imaging in patients with thalassemia major: short-term follow-up
Authors: Bayav Murat , Isiksalan Ozbulbul Nilgun , Bor Ozcan
Published: August 2020

Objective

This study was performed to assess cardiac and hepatic iron overload in young patients with thalassemia.

Methods

We reviewed the medical records of patients with thalassemia at a pediatric hematology clinic who had recently undergone cardiac and hepatic magnetic resonance imaging.

Results

Eleven patients underwent cardiac and hepatic T2* imaging at a mean age of 13.9 ± 4.48 (range, 9–21) years. Three patients had cardiac iron overload and all patients had hepatic iron overload according to the magnetic resonance imaging scan. Ten patients underwent control imaging approximately 1 year later. The mean serum ferritin level at the initial imaging examination was 1820.87 ± 1275.22 (range, 634.04–4221.03) ng/mL. There was a strong negative correlation between the ferritin level and cardiac T2* time and between the blood hemoglobin level and hepatic T2* time. Among the 10 patients who underwent control imaging, the average hemoglobin and ferritin levels significantly decreased from the initial to control imaging examinations, but there was no significant increase in the cardiac and hepatic T2*times.

Conclusions

Cardiac and hepatic T2* imaging is a feasible method of assessing cardiac and hepatic iron overload even before complications and clinical signs of iron overload appear.
Hydrogen-rich saline mitigates pressure overload-induced cardiac hypertrophy and atrial fibrillation in rats via the JAK-STAT signalling pathway
Authors: Wang Chufeng , Pan Zezheng
Published: August 2020

Objective

To investigate if hydrogen-rich saline (HRS), which has been shown to have antioxidant and anti-inflammatory properties, could mitigate cardiac remodelling and reduce the incidence of atrial fibrillation (AF) in the rat model of cardiac hypertrophy.

Methods

Pressure overload was induced in rats by abdominal aortic constriction (AAC). The animals were separated into four groups: sham; AAC group; AAC plus low dose HRS (LHRS); AAC plus high dose HRS (HHRS). The sham and AAC groups received normal saline intraperitoneally and the LHRS and HHRS groups received 3 or 6 ml/kg HRS daily for six weeks, respectively. In vitro research was also performed using cardiotrophin-1 (CT-1)-induced hypertrophy of cultured neonatal rat cardiomyocytes.

Results

Cardiac hypertrophy was successfully induced by AAC and low and high dose HRS mitigated the pressure overload as shown by lower heart and atrial weights in these treatment groups. AF incidence and duration of the HRS groups were also significantly lower in the HRS groups compared with the AAC group. Atrial fibrosis was also reduced in the HRS groups and the JAK-STAT signalling pathway was down-regulated. In vitro experiments showed that hydrogen-rich medium mitigated the CT-1-induced cardiomyocyte hypertrophy with a similar effect as the JAK specific antagonists AG490.

Conclusions

HRS was found to mitigate cardiac hypertrophy induced by pressure overload in rats and reduce atrial fibrosis and AF which was possibly achieved via inhibition of the JAK-STAT signalling pathway.
Jaundice may be the only clinical manifestation of primary hepatosplenic diffuse large B-cell lymphoma: a case report and literature review
Authors: Shi Xue , Zhang Tingting , Xu Hong , Zhang Xiaoying , Zhao Hongguo , Liu Xiaodan , Hou Fang , Yang Guangjie , Liu Zhihe
Published: August 2020

A 64-year old Chinese male patient was admitted to our hospital because of severe jaundice that persisted for 2 months. No swollen lymph nodes or hepatosplenomegaly was detected on physical examination. His laboratory data indicated high levels of direct bilirubin, alkaline phosphatase, aspartate aminotransferase, and alanine aminotransferase. No abnormality was revealed on abdominal computed tomography (CT). However, positron emission tomography (PET)-CT revealed diffuse hypermetabolism in the liver and spleen. Ultimately, liver biopsy guided by PET-CT was performed, revealing that atypical lymphocytes diffusely infiltrated the liver. The immunohistochemical analysis demonstrated that the tumor cells were positive for CD20, Bcl-2, Bcl-6, MUM1, and c-Myc but negative for CD3, CD4, CD8, and CD10. Based on these findings, this patient was diagnosed with primary hepatosplenic diffuse large B-cell lymphoma. After the definite diagnosis, he received chemotherapy and remained in good health as of September 2019.
Removal of giant spherical foreign body in the esophagus by double-forceps endoscope and double balloon
Authors: Yu Shan , Wang Xiaoming , Chen Xin
Published: August 2020

In patients with esophageal foreign bodies such as spherical or similarly shaped objects, a clamp or trap can easily fall off when the esophagus is physiologically narrow during removal of the foreign body by the endoscope. In the present case, a double-forceps-channel endoscope and double balloon were used to successfully remove a large spherical foreign body from the esophagus.
Bioavailable testosterone is associated with symptoms of depression in adult men
Authors: Chen Zhongbao , Shen Xubo , Tian Kunming , Liu Yijun , Xiong Shimin , Yu Qin , Dai Lulu , Shi Yongjun , Zhang Renjuan , Zeng Rong , Wan Qiyou , Xiong Chengliang , Zhou Yuanzhong
Published: August 2020

Objective

This study aimed to determine the relationship between serum testosterone levels and depressive symptoms in an adult male population.

Methods

We conducted a cross-sectional study of 1166 male participants from Zunyi, Guizhou, China. Each participant completed a questionnaire, a brief clinical exam, and had a fasting blood sample taken. We measured serum testosterone, sex hormone-binding globulin, and luteinizing hormone levels. Multiple linear regression was used to evaluate the effect of demographic factors on the relationship between the depressive symptom score and serum sex hormone levels.

Results

Mean testosterone, sex hormone-binding globulin, and luteinizing hormone levels were significantly higher in the depressive symptom group than in the non-depressed group. The mean calculated free serum testosterone level and free testosterone index (FTI) were significantly lower in the depressive symptom group than in the non-depressed group. Additionally, the mean FTI was significantly negatively correlated with the Beck Depression Inventory scale score in the multiple linear regression model (95% confidence interval: −3.274 to −0.406).

Conclusions

Decreased bioactive testosterone levels might be a contributing factor of depression in adult men. The FTI could be the most sensitive biomarker reflecting the level of bioavailable testosterone in patients with depression.
Is nab-paclitaxel better than conventional taxanes as neoadjuvant therapy for breast cancer? A meta-analysis
Authors: Li Yong , Lu Xiaoju , Lin Qimou , Li Weiwen
Published: August 2020

Objective

This study compared the efficacy and safety of nanoparticle albumin-bound paclitaxel (nab-paclitaxel) with conventional taxanes as neoadjuvant chemotherapy for breast cancer.

Methods

We searched the literature using PubMed, the Cochrane Library, and Web of Science from their inception to December 15, 2019 based on predetermined inclusion and exclusion criteria. The relevant studies compared pathologic complete response (pCR) and adverse event rates.

Results

The meta-analysis included five studies and 2335 patients. Compared with conventional taxanes, neoadjuvant chemotherapy with nab-paclitaxel was associated with a higher pCR rate (odds ratio [OR] = 1.39, 95% confidence interval [CI] = 1.16–1.67), especially among patients with triple-negative breast cancer or Ki67 indices of >20%. Pooled outcomes also revealed better event-free survival in the nab-paclitaxel group (hazard ratio = 0.69, 95% CI = 0.57–0.85). However, all-grade (OR = 2.17, 95% CI = 1.38–3.40) and grade ≥3 peripheral sensory neuropathy (OR = 3.92, 95% CI = 2.44–6.28) were more frequent in the nab-paclitaxel group.

Conclusions

This meta-analysis implied that nab-paclitaxel more effectively improved pCR than conventional taxanes. Nab-paclitaxel may have greater benefits in patients with triple-negative breast cancer. However, additional attention is required for the early diagnosis and management of peripheral sensory neuropathy.
Palestinian leadership and the contemporary significance of the First Intifada
Authors: Naser-Najjab Nadia
Published: August 2020

On the eve of the highly controversial 2020 plan for Israel to annex parts of the West Bank, the author examines the nature of the Palestinian condition and the many challenges Palestinians confront, including the absence of an effective leadership. In registering this, the article proposes a reassessment of the First Intifada that places it in a contemporary perspective and seeks to ‘excavate’ modes of resistance. It engages with the problematic of leadership and highlights how existing challenges might be addressed. Taking into account the Oslo Accords and subsequent attempts towards neoliberal state-building, it draws on theories of settler colonialism and stresses the neo-colonial continuum in Palestine. Finally, the author interviews key activists from the First Intifada to (respectively) provide insight into the nature of the contemporary situation and suggest an alternative model of leadership and struggle.
3D-Printed Extracellular Matrix/Polyethylene Glycol Diacrylate Hydrogel Incorporating the Anti-inflammatory Phytomolecule Honokiol for Regeneration of Osteochondral Defects
Authors: Zhu Shouan , Chen Pengfei , Chen Yang , Li Muzhi , Chen Can , Lu Hongbin
Published: August 2020

Background:

Osteoarthritis is the leading cause of disability worldwide; cartilage degeneration and defects are the central features. Significant progress in tissue engineering holds promise to regenerate damaged cartilage tissue. However, a formidable challenge is to develop a 3-dimensional (3D) tissue construct that can regulate local immune environment to facilitate the intrinsic osteochondral regeneration.

Purpose:

To evaluate efficacy of a 3D-printed decellularized cartilage extracellular matrix (ECM) and polyethylene glycol diacrylate (PEGDA) integrated novel scaffold (PEGDA/ECM) together with the natural compound honokiol (Hon) for regenerating osteochondral defect.

Study Design:

Controlled laboratory study.

Methods:

We used a stereolithography-based 3D printer for PEGDA/ECM bioprinting. A total of 36 Sprague-Dawley rats with cylindrical osteochondral defect in the trochlear groove of the femur were randomly assigned into 3 different treatments: no scaffold implantation (Defect group), 3D printed PEGDA/ECM scaffold alone (PEGDA/ECM group), or Hon suspended in a 3D-printed PEGDA/ECM scaffold (PEGDA/ECM/Hon group). 12 rats that underwent only medial parapatellar incision surgery were used as normal controls. The femur specimens were postoperatively harvested at 4 and 8 weeks for gross, micro-CT, and histological evaluations. The efficacy of PEGDA/ECM/Hon scaffold on the release of proinflammatory cytokines from the macrophages stimulated by lipopolysaccharide (LPS) was evaluated in-vitro.

Results:

In vitro results determined that PEGDA/ECM/Hon scaffold could suppress the release of proinflammatory cytokines from macrophages that were stimulated by LPS. Macroscopic images showed that the PEGDA/ECM/Hon group had significantly higher ICRS scoring than that of defect and PEGDA/ECM groups. Micro-CT evaluation demonstrated that much more bony tissue was formed in the defect sites implanted with the PEGDA/ECM scaffold or PEGDA/ECM/Hon scaffold compared with the untreated defects. Histological analysis showed that the PEGDA/ECM/Hon group had a significant enhancement in osteochondral regeneration at 4 and 8 weeks after surgery in comparison with the ECM/PEGDA or defect group.

Conclusion:

This study demonstrated that 3D printing of PEGDA/ECM hydrogel incorporating the anti-inflammatory phytomolecule honokiol could provide a promising scaffold for osteochondral defect repair.
The Hip Suction Seal, Part I: The Role of Acetabular Labral Height on Hip Distractive Stability
Authors: Storaci Hunter W. , Utsunomiya Hajime , Kemler Bryson R. , Rosenberg Samuel I. , Dornan Grant J. , Brady Alex W. , Philippon Marc J.
Published: August 2020

Background:

The acetabular labrum has been found to provide a significant contribution to the distractive stability of the hip. However, the influence of labral height on hip suction seal biomechanics is not known.

Hypothesis:

The smaller height of acetabular labrum is associated with decreased distractive stability.

Study Design:

Descriptive laboratory study.

Methods:

A total of 23 fresh-frozen cadaveric hemipelvises were used in this study. Hips with acetabular dysplasia or femoroacetabular impingement–related bony morphologic features, intra-articular pathology, or no measurable suction seal were excluded. Before testing, each specimen’s hip capsule was removed, a pressure sensor was placed intra-articularly, and the hip was fixed in a heated saline bath. Labral size was measured by use of a digital caliper. Maximum distraction force, distance to suction seal rupture, and peak negative pressure were recorded while the hip underwent distraction at a rate of 0.5 mm/s. Correlations between factors were analyzed using the Spearman rho, and differences between groups were detected using Mann-Whitney U test.

Results:

Of 23 hips, 12 satisfied inclusion criteria. The maximum distraction force and peak negative pressure were significantly correlated ( R = −0.83; P = .001). Labral height was largely correlated with all suction seal parameters (maximum distraction force, R = 0.69, P = .013; distance to suction seal rupture, R = 0.55, P = .063; peak negative pressure, R = −0.62, P = .031). Labral height less than 6 mm was observed in 5 hips, with a mean height of 6.48 mm (SD, 2.65 mm; range, 2.62-11.90 mm; 95% CI, 4.80-8.17 mm). Compared with the 7 hips with larger labra (>6 mm), the hips with smaller labra had significantly shorter distance to suction seal rupture (median, 2.3 vs 7.2 mm; P = .010) and significantly decreased peak negative pressure (median, −59.3 vs −66.9 kPa; P = .048).

Conclusion:

Smaller height (<6 mm) of the acetabular labrum was significantly associated with decreased distance to suction seal rupture and decreased peak negative pressure. A new strategy to increase the size of the labrum, such as labral augmentation, could be justified for patients with smaller labra in order to optimize the hip suction seal.

Clinical Relevance:

The height of the acetabular labrum is correlated with hip suction seal biomechanics. Further studies are required to identify the clinical effects of labral height on hip stability.
The Hip Suction Seal, Part II: The Effect of Rim Trimming, Chondrolabral Junction Separation, and Labral Repair/Refixation on Hip Distractive Stability
Authors: Utsunomiya Hajime , Storaci Hunter W. , Rosenberg Samuel I. , Kemler Bryson R. , Dornan Grant J. , Brady Alex W. , Philippon Marc J.
Published: August 2020

Background:

The acetabular labrum contains free nerve endings, and an unstable labrum can result in increased femoral head movement during hip motion. This can be caused by chondrolabral junction (CLJ) separation, especially in association with pincer-type femoroacetabular impingement, and may contribute to hip pain.

Hypothesis:

Rim resection alone has no effect on suction seal biomechanics. Further, separation of the CLJ changes hip suction seal biomechanics when compared with those of the native state, whereas repair and refixation with suture anchors restore these biomechanical parameters.

Study Design:

Controlled laboratory study.

Methods:

A total of 12 fresh-frozen human cadaveric hips were used in this study. Hips were mounted in a saline bath on a dynamic tensile testing machine and were distracted at a rate of 0.5 mm/s from neutral position. A total of 3 parameters (force, displacement, and intra-articular pressure) were measured throughout testing. Before testing, hips were randomly allocated to 1 of 2 groups: 1 that included the CLJ separation (CLJ Cut group) and 1 that did not (CLJ Intact group). Hips were tested in the following states: (1) native, (2) rim trimming, (3) separated CLJ (CLJ Cut group only), and (4) labral repair/refixation. For each group a linear mixed-effects model was used to compare biomechanical parameters between states.

Results:

Rim trimming did not affect any suction seal parameters relative to those of the native state. In the CLJ Cut group, no significant difference in distance to break the suction seal was observed for any states compared with that of the native state. In the CLJ Intact group, the distance to break the suction seal was significantly shorter in the labral refixation state (1.8 mm) than the native state (5.6 mm; P = .002). The maximum distraction force (62.1 ± 54.1 N) and the peak negative pressure (−36.6 ± 24.2 kPa) of the labral repair/refixation state were significantly lower than those of the native state in both groups (93.4 ± 41.7 N, P = .01; –60.7 ± 20.4 kPa, P = .02).

Conclusion:

Rim trimming did not change the biomechanical properties of the labral suction seal. Labral refixation resulted in a shorter distance to break the labral suction seal. This indicates that labral mobility is reduced by the labral refixation procedure, which could be beneficial in postoperative pain relief and labral healing.

Clinical Relevance:

The labral refixation reduced labral mobility, which could be beneficial for both pain relief and labral healing to the acetabulum after pincer-type femoroacetabular impingement resection.
Modeling Quality of Life in Alzheimer Disease: The Impact of Cognitive, Functional, and Mood Variables in Self and Carers’ Perceptions
Authors: Dourado Marcia Cristina Nascimento , Santos Raquel Luiza , Fischer Anna , Mograbi Daniel C.
Published: August 2020

Quality of life (QoL) includes complex interactions between objective and subjective factors. Through structural equation modeling, we analyzed people with Alzheimer disease (PwAD) and carers’ ratings to identify the factors associated with PwAD QoL. We included 264 PwAD and their carers. Model 1, carers’ ratings of PwAD QoL, showed a bidirectional association with worse depressive symptoms, lower functionality, and impairment on awareness being linked. These variables were associated with burden and all of them directly affecting carers’ ratings of PwAD QoL. Model 2, PwAD self-reported QoL, had the same bidirectional associations among the same variables with all of them influencing PwAD self-reported QoL. However, the interpretations of these similar associations should be different. The path analysis increased the understanding of the relationship between QoL and cognition, functionality, mood, awareness, and burden. Our findings bring together a number of consistent predictors and confirm their different effects in PwAD and carers’ point of view about QoL.
A Systematic Review and Comparison of Neurocognitive Features of Late-Life Attention-Deficit/Hyperactivity Disorder and Dementia With Lewy Bodies
Authors: Prentice Jennifer L. , Schaeffer Morgan J. , Wall Alexandra K. , Callahan Brandy L.
Published: August 2020

Objective:

Attention-deficit/hyperactivity disorder (ADHD) in adulthood and dementia with Lewy bodies (DLB) share many cognitive and noncognitive similarities. The overlapping features between both disorders complicate differential diagnosis. The aim of the current systematic review was to compare patterns of neuropsychological profiles in older adults with ADHD and DLB.

Method:

Of the 1989 ADHD-related articles and 1332 DLB-related articles screened, 3 ADHD and 25 DLB articles were retained for qualitative synthesis and review.

Results:

A synthesis of individual study findings revealed isolated working memory deficits for late-life ADHD, and performance deficits in areas of attention, memory, language, and visuoperceptual abilities for DLB. Results were limited by small samples and absence of data in some cognitive domains.

Conclusion:

These initial findings support potentially unique neurocognitive profiles for ADHD in later life and DLB that would enable practitioners to differentially diagnose and appropriately treat older adults presenting with these phenotypically similar disorders.
Two-different ways of synthesis for EG: Study of mechanical, thermal, and electrical properties of epoxy composite for TIMs
Authors: Nayak Sagar Kumar , Mishra Arjyama , Pradhan Subhransu S , Agarwal Jyoti
Published: August 2020

The current study reports the synthesis of expanded graphite (EG) in two different ways and its fabrication with epoxy matrix to form composite at various filler fractions (5, 10, 12.5). One type EG (EG-C) is prepared by the electrochemical process using natural graphite flake (NGF), concentrated sulfuric acid, and ammonium persulfate, while the other (EG-P) is just mixing and heating of NGF with zinc nitrate hexahydrate. The functional groups of synthesized EG were confirmed by Fourier transform infrared spectroscopy. The surface morphology and microstructure of synthesized filler (EG-C, EG-P) were studied using X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. An optimum through-plane thermal conductivity (TC) of 2.04 and 2.22 W/mK was observed in the case of the composites containing 12.5 wt% of EG-C and EG-P, respectively. The obtained experimental TC was compared with three numerical thermal models, that is, inverse rule of mixture, Maxwell–Eucken model, and Agari model. Furthermore, the thermal stability of both composites was compared by using a thermogravimetric analyzer. The electrical resistivity of EG-P/epoxy composite at different formulations was higher than the EG-C-filled epoxy composites.
Nanosecond dielectric barrier discharge–based dynamic stall control on an SC-1095 airfoil
Authors: Yang He-sen , Liang Hua , Zhao Guang-yin
Published: August 2020

Dynamic stall is a time-dependent flow separation and stall phenomenon that is present in many applications, including violently maneuvering aircraft, surging compressor, wind turbine, and, most observably, rotorcraft. Nanosecond dielectric barrier discharge plasma actuator has previously demonstrated the control ability in static stall conditions and shows promise to address dynamic stall. The present work explores the ability of nanosecond dielectric barrier discharge to control dynamic stall over an SC-1095 airfoil and summarizes the control law of actuation parameters. The actuation voltage, actuation frequency, and reduced frequencies were varied over large ranges: Vp–p = 7–13 kV, F+ = 0.5–10, and k = 0.05–0.15. Direct aerodynamic measurements were taken for each combination of actuation voltages and actuation frequencies, and fixed combination at different experimental reduced frequencies. It was observed that nanosecond dielectric barrier discharge could effectively improve the dynamic stall characteristics, and three major conclusions were drawn. First, there is a threshold for actuation voltage. Only when the actuation voltage is greater than or equal to the threshold voltage can the separation be effectively suppressed and the steep stall can be alleviated. Second, High F+ has better control performance of maintaining peak lift in the stall regime and achieves better effects in moment control and drag reduction while lift reattachment is better with low F+ on downstroke. Last, with the increase of reduced frequency, the control effect of nanosecond dielectric barrier discharge with settled actuation parameter combination becomes worse, so greater cost needs to be paid for effective control at a larger reduced frequency.
Effects of Talinum paniculatum (Jacq.) Gaertn. leaf extract on general toxicity and pubertal development of rats
Authors: Tolouei SEL , da Silva GN , Curi TZ , Passoni MT , Ribeiro DCK , Meldola HG , Grechi N , Hey GS , Souza RIC , dos Santos AC , Beltrame OC , Dalsenter PR , Martino-Andrade AJ , Gasparotto Junior A
Published: August 2020

Talinum paniculatum (Jacq.) Gaertn. (Talinaceae), popularly known as “major gomes,” is a Brazilian Cerrado plant used in traditional medicine and as a food source. Recent studies have demonstrated its diuretic effects. However, no studies have been performed on its effects on the reproductive system. Therefore, we aimed to investigate the effects of the ethanol-soluble fraction of T. paniculatum leaves (ESTP) on general toxicity and on the pubertal development of male and female Wistar rats. For this purpose, the uterotrophic and the pubertal assays were performed. In the uterotrophic test, female immature rats were treated for three consecutive days with 30, 100, or 300 mg/kg of ESTP. Uterus without luminal fluid was weighed and the relative weight calculated. For the pubertal assay, male and female immature rats were submitted to 30-day treatment with 30 or 300 mg/kg of ESTP. Clinical signs of toxicity, biochemical, and histopathological parameters were evaluated. ESTP treatment did not promote estrogenic effects in female rats. In the pubertal test, no daily signs of toxicity or weight loss were observed. Moreover, ESTP did not affect the onset of vaginal opening and preputial separation and did not cause significant changes in biochemical parameters as well as in organ weight and histopathological analyses of animals.
Hepatic injury induced by radio frequency waves emitted from conventional Wi-Fi devices in Wistar rats
Authors: Fahmy HM , Mohammed FF
Published: August 2020

In this study, the impact of standard 2.45 GHz radio frequency source (averaged whole-body specific absorption rate 0.01 W kg−1 24 h−1 daily for 40 consecutive days) on the liver of Wistar female rats was investigated. The rats were randomly divided into control and Wi-Fi–exposed groups. At the end of the exposure, liver samples were dissected from rats. Rats’ livers were inspected through the evaluation of some oxidative stress parameters and the evaluation of glutamic oxaloacetic transaminase and glutamic-pyruvic transaminase levels as well as through the molecular investigation using Fourier transform infrared spectroscopy. Histopathological examination in addition to ultrastructure examination was also performed. The present data revealed that Wi-Fi exposure leads to severe oxidative stress in the rat liver. Furthermore, Wi-Fi exposure resulted in deleterious effects in the liver function and alters its molecular structure. Moreover, severe histological and ultrastructural alterations are reported in the hepatic tissues points to hepatotoxic effects induced by Wi-Fi exposure. In conclusion, care must be taken when using Wi-Fi emitting devices due to their severe impact on the liver. Public awareness of the need to decrease exposure time and increase the distance from Wi-Fi exposure sources must be raised wherever possible.
Defects in the Kevlar-epoxy thin layer sheet drilling with different machining strategies
Authors: Baharlooey Dariush , Abootorabi Mohammad Mahdi
Published: August 2020

Assembly of Most composite components requires secondary machining operations, such as drilling. Various methods such as drilling by means of twist drills bits, laser beam and abrasive jet machining are used to drill these materials, and twist drill bit is considered to be the most inexpensive and most commonly used method. The present paper is an attempt to investigate the effect of feed rate and rotational speed of drill bit on delamination rate during drilling of a 1.4 mm thick Kevlar-epoxy composite sheet as well as the hole diameter error in this sheet. Kevlar fibers are widely used in composites that are utilized in the aerospace industry. 4 feed rate levels and 4 spindle speed levels were selected to conduct a full-factorial experiment and each experiment was repeated three times. The effects of pre-drilling, compressed air, layer of leather on a Kevlar-epoxy sheet and the innovative strategy of simultaneous use of pre-drilling and a leather layer, on the delamination factor and hole diameter error was also investigated in the present study. The results indicate a significant reduction in delamination factor and hole diameter error in simultaneous use of pre-drilling and a leather layer on the composite sheet.
Lifetime Employment and Stackelberg Mixed Duopoly Games with a Foreign Labour-Managed Competitor
Authors: Ohnishi Kazuhiro
Published: August 2020

This article considers two Stackelberg games in which a state-owned firm competes against a foreign labour-managed firm. The first game is as follows. In the first stage, the state-owned firm decides whether to offer lifetime employment as a strategic commitment device. In the second stage, the foreign labour-managed firm decides whether to offer lifetime employment as a strategic commitment device. In the third stage, both firms simultaneously and independently choose actual outputs. The structure of the second game is nearly identical and differs only in the order in which the firms decide on the offer of lifetime employment in the first two stages. This study presents the equilibrium outcomes of these two Stackelberg games.

JEL: C72, D21, F23, L30
Faith Beliefs of African American Church Leaders Are Aligned With the Principles of Palliative and Hospice Care: A Community-Based Assessment and Intervention
Authors: Johnson Jerry , Hayden Tara , Taylor Lynne Allen , Arthur Gilbert M.
Published: August 2020

Background:

African American (AA) church leaders often advise AAs with serious and life-limiting illnesses (LLIs).

Objectives:

1) determine beliefs of AA church leaders about palliative care and hospice care (PCHC), 2) assess association of participants’ attitude about encouraging a loved one to learn about PCHC with whether PC or HC is consistent with faith beliefs and can reduce suffering and bring comfort, and 3) evaluate an interactive, educational intervention.

Design:

prospective, one group, pre and post assessment of beliefs and attitudes Settings/Subjects: 100 church leaders from 3 AA Churches and one AA Church Consortium.

Results:

At baseline, participants held more receptive beliefs about HC than about PC. Those who reported knowing the meaning of PC believed PC is consistent with their faith (81% vs 28%, phi=.53) and can reduce suffering and bring comfort (86% vs 38%, phi =.50). Participants who believed PC was consistent with their faith were more likely to encourage a loved one with a LLI to learn about PCHC than did participants who did not (100% vs 77%, phi =.39, p < 0.001). Post intervention, more participants: 1) perceived that they knew the meaning of PC (48% vs 96%), 2) viewed PC as consistent with their faith (58% vs. 94%), and 3) viewed PC as a means to reduce suffering and bring comfort (67% vs 93%) with a p < 0.0001 for each item. The post intervention results for HC were variable.

Conclusions:

Faith beliefs of AA Church leaders may be aligned with the principles of PCHC.