Showing papers by "Albion College published in 2020"

Global status and conservation potential of reef sharks

Abstract: Decades of overexploitation have devastated shark populations, leaving considerable doubt as to their ecological status1,2. Yet much of what is known about sharks has been inferred from catch records in industrial fisheries, whereas far less information is available about sharks that live in coastal habitats3. Here we address this knowledge gap using data from more than 15,000 standardized baited remote underwater video stations that were deployed on 371 reefs in 58 nations to estimate the conservation status of reef sharks globally. Our results reveal the profound impact that fishing has had on reef shark populations: we observed no sharks on almost 20% of the surveyed reefs. Reef sharks were almost completely absent from reefs in several nations, and shark depletion was strongly related to socio-economic conditions such as the size and proximity of the nearest market, poor governance and the density of the human population. However, opportunities for the conservation of reef sharks remain: shark sanctuaries, closed areas, catch limits and an absence of gillnets and longlines were associated with a substantially higher relative abundance of reef sharks. These results reveal several policy pathways for the restoration and management of reef shark populations, from direct top-down management of fishing to indirect improvement of governance conditions. Reef shark populations will only have a high chance of recovery by engaging key socio-economic aspects of tropical fisheries. Fishing has had a profound impact on global reef shark populations, and the absence or presence of sharks is strongly correlated with national socio-economic conditions and reef governance.

Toward Drug-Like Multispecific Antibodies by Design.

Abstract: The success of antibody therapeutics is strongly influenced by their multifunctional nature that couples antigen recognition mediated by their variable regions with effector functions and half-life extension mediated by a subset of their constant regions. Nevertheless, the monospecific IgG format is not optimal for many therapeutic applications, and this has led to the design of a vast number of unique multispecific antibody formats that enable targeting of multiple antigens or multiple epitopes on the same antigen. Despite the diversity of these formats, a common challenge in generating multispecific antibodies is that they display suboptimal physical and chemical properties relative to conventional IgGs and are more difficult to develop into therapeutics. Here we review advances in the design and engineering of multispecific antibodies with drug-like properties, including favorable stability, solubility, viscosity, specificity and pharmacokinetic properties. We also highlight emerging experimental and computational methods for improving the next generation of multispecific antibodies, as well as their constituent antibody fragments, with natural IgG-like properties. Finally, we identify several outstanding challenges that need to be addressed to increase the success of multispecific antibodies in the clinic.

Precision cardiovascular medicine: artificial intelligence and epigenetics for the pathogenesis and prediction of coarctation in neonates.

Abstract: Background: Advances in omics and computational Artificial Intelligence (AI) have been said to be key to meeting the objectives of precision cardiovascular medicine. The focus of precision medicine includes a better assessment of disease risk and understanding of disease mechanisms. Our objective was to determine whether significant epigenetic changes occur in isolated, non-syndromic CoA. Further, we evaluated the AI analysis of DNA methylation for the prediction of CoA.Methods: Genome-wide DNA methylation analysis of newborn blood DNA was performed in 24 isolated, non-syndromic CoA cases and 16 controls using the Illumina HumanMethylation450 BeadChip arrays. Cytosine nucleotide (CpG) methylation changes in CoA in each of 450,000 CpG loci were determined. Ingenuity pathway analysis (IPA) was performed to identify molecular and disease pathways that were epigenetically dysregulated. Using methylation data, six artificial intelligence (AI) platforms including deep learning (DL) was used for CoA detection.Results: We identified significant (FDR p-value ≤ .05) methylation changes in 65 different CpG sites located in 75 genes in CoA subjects. DL achieved an AUC (95% CI) = 0.97 (0.80-1) with 95% sensitivity and 98% specificity. Gene ontology (GO) analysis yielded epigenetic alterations in important cardiovascular developmental genes and biological processes: abnormal morphology of cardiovascular system, left ventricular dysfunction, heart conduction disorder, thrombus formation, and coronary artery disease.Conclusion: In an exploratory study we report the use of AI and epigenomics to achieve important objectives of precision cardiovascular medicine. Accurate prediction of CoA was achieved using a newborn blood spot. Further, we provided evidence of a significant epigenetic etiology in isolated CoA development.

Pan-regional marine benthic cryptobiome biodiversity patterns revealed by metabarcoding Autonomous Reef Monitoring Structures.

Abstract: Autonomous Reef Monitoring Structures (ARMS) have been applied worldwide to characterize the critical yet frequently overlooked biodiversity patterns of marine benthic organisms. In order to disentangle the relevance of environmental factors in benthic patterns, here, through standardized metabarcoding protocols, we analyse sessile and mobile (<2 mm) organisms collected using ARMS deployed across six regions with different environmental conditions (3 sites × 3 replicates per region): Baltic, Western Mediterranean, Adriatic, Black and Red Seas, and the Bay of Biscay. A total of 27,473 Amplicon Sequence Variants (ASVs) were observed ranging from 1,404 in the Black Sea to 9,958 in the Red Sea. No ASVs were shared among all regions. The highest number of shared ASVs was between the Western Mediterranean and the Adriatic Sea (116) and Bay of Biscay (115). Relatively high numbers of ASVs (103), mostly associated with the genus Amphibalanus, were also shared between the lower salinity seas (Baltic and Black Seas). We found that compositional differences in spatial patterns of rocky-shore benthos are determined slightly more by dispersal limitation than environmental filtering. Dispersal limitation was similar between sessile and mobile groups, while the sessile group had a larger environmental niche breadth than the mobile group. Further, our study can provide a foundation for future evaluations of biodiversity patterns in the cryptobiome, which can contribute up to 70% of the local biodiversity.

Trends in Chondrichthyan Research: An Analysis of Three Decades of Conference Abstracts

Abstract: Given the conservation status and ecological, cultural, and commercial importance of chondrichthyan fishes, it is valuable to evaluate the extent to which research attention is spread across taxa and geographic locations and to assess the degree to which scientific research is appropriately addressing the challenges they face. Here we review trends in research effort over three decades (1985–2016) through content analysis of every abstract (n = 2,701) presented at the annual conference of the American Elasmobranch Society (AES), the oldest and largest professional society focused on the scientific study and management of these fishes. The most common research areas of AES abstracts were reproductive biology, movement/telemetry, age and growth, population genetics, and diet/feeding ecology, with different areas of focus for different study species or families. The most commonly studied species were large and charismatic (e.g., White Shark, Carcharodon carcharias), easily accessible to long-term established field research programs (e.g., Lemon Shark, Negaprion brevirostris, and Sandbar Shark, Carcharhinus plumbeus), or easily kept in aquaria for lab-based research (e.g., Bonnethead Shark, Sphyrna tiburo). Nearly 90% of all described chondrichthyan species have never been mentioned in an AES abstract, including some of the most threatened species in the Americas. The proportion of female* first authors has increased over time, though many current female* Society members are graduate students. Nearly half of all research presented at AES occurred in the waters of the United States rather than in the waters of developing nations where there are more threatened species and few resources for research or management. Presentations based on research areas such as paleontology and aquarium-based research have declined in frequency over time, and identified research priorities such as social science and interdisciplinary research are poorly represented. Possible research gaps and future research priorities for the study of chondrichthyan fishes are also discussed.

Doing, Caring, and Being: “Good” Mentoring and Its Role in the Socialization of Graduate Students of Color in STEM

Abstract: This chapter applies and extends Weidman, Twale, and Stein’s (2001) socialization framework by incorporating sociocultural conceptions of learning (SCL) to more deeply explore how relationships and interactions with faculty can foster students’ socialization, learning, and process of becoming scientists. Interviews with seventeen Black and Latinx science graduate students suggest good mentors offer both opportunities to engage in community practices, or activities specific to the intended career (e.g., presentations, research), as well as focused guidance regarding how to engage in skills and behaviors that would allow them to become scientists. In addition, participants sought personal commitments and connections with their mentors that enhanced their ability to share their thoughts and engage in community practices with more confidence. Findings remind institutional leaders, faculty, and scholars that efforts to foster graduate student socialization must go beyond access to opportunities to learn or participate in community practices. They must also incorporate relational strategies such as guidance and care, which build students’ confidence as they engage in knowledge acquisition and deepen their commitments to science.

Facilitating Growth through Frustration: Using Genomics Research in a Course-Based Undergraduate Research Experience.

Abstract: A hallmark of the research experience is encountering difficulty and working through those challenges to achieve success. This ability is essential to being a successful scientist, but replicating such challenges in a teaching setting can be difficult. The Genomics Education Partnership (GEP) is a consortium of faculty who engage their students in a genomics Course-Based Undergraduate Research Experience (CURE). Students participate in genome annotation, generating gene models using multiple lines of experimental evidence. Our observations suggested that the students' learning experience is continuous and recursive, frequently beginning with frustration but eventually leading to success as they come up with defendable gene models. In order to explore our "formative frustration" hypothesis, we gathered data from faculty via a survey, and from students via both a general survey and a set of student focus groups. Upon analyzing these data, we found that all three datasets mentioned frustration and struggle, as well as learning and better understanding of the scientific process. Bioinformatics projects are particularly well suited to the process of iteration and refinement because iterations can be performed quickly and are inexpensive in both time and money. Based on these findings, we suggest that a dynamic of "formative frustration" is an important aspect for a successful CURE.

Knowledge of physical activity and nutrition recommendations in college students.

Abstract: Objective: Assess physical activity (PA) and nutrition recommendation knowledge in college students. Participants: 71 students (n = 41 females;18 to 22 years) measured in May of 2014. METHODS: Know...

Cometary Glycolaldehyde as a Source of pre-RNA Molecules.

Abstract: Over 200 molecules have been detected in multiple extraterrestrial environments, including glycolaldehyde (C2(H2O)2, GLA), a two-carbon sugar precursor that has been detected in regions of the interstellar medium. Its recent in situ detection on the nucleus of comet 67P/Churyumov-Gerasimenko and through remote observations in the comae of others provides tantalizing evidence that it is common on most (if not all) comets. Impact experiments conducted at the Experimental Impact Laboratory at NASA's Johnson Space Center have shown that samples of GLA and GLA mixed with montmorillonite clays can survive impact delivery in the pressure range of 4.5 to 25 GPa. Extrapolated to amounts of GLA observed on individual comets and assuming a monotonic impact rate in the first billion years of Solar System history, these experimental results show that up to 1023 kg of cometary GLA could have survived impact delivery, with substantial amounts of threose, erythrose, glycolic acid, and ethylene glycol also produced or delivered. Importantly, independent of the profile of the impact flux in the early Solar System, comet delivery of GLA would have provided (and may continue to provide) a reservoir of starting material for the formose reaction (to form ribose) and the Strecker reaction (to form amino acids). Thus, comets may have been important delivery vehicles for starting molecules necessary for life as we know it.

Ransomware 2.0: to sell, or not to sell a game-theoretical model of data-selling Ransomware

Abstract: Cybercrime such as ransomware denies access to valuable data until a ransom is paid. Recent ransomware attacks on organizations such as hospitals, schools, government agencies and private businesses raise public awareness of the severe impact on the society. In this paper, we propose a hypothetical new revenue model for the ransomware, i.e., selling the stolen data. Through a game-theoretical analysis between attackers and victims, we contribute a novel model to understand the critical decision variables between the traditional ransomware (ransomware 1.0) - demanding ransom only and the new type of ransomware (ransomware 2.0) - selling the data as well as demanding ransom. Both theoretical modeling and simulation studies suggest that in general ransomware 2.0 is more profitable than ransomware 1.0. Common defensive measures that may work to eliminate the financial incentives of ransomware 1.0 may not work on ransomware 2.0, in particular the data backup practice and the never-pay-ransom strategy. Nevertheless, the uncertainties created by this new revenue model may affect attackers' reputation and users' willingness-to-pay. In turn, ransomware 2.0 may not always increase the profitability of attackers. Another finding of the study suggests that reputation maximization is critical in ransomware 1.0 but not in ransomware 2.0, where attackers should seek imperfect reputation for profit maximization.

Thermodynamic modeling of high-grade metabasites: a case study using the Tso Morari UHP eclogite

Abstract: Thermodynamic modeling is an important technique to simulate the evolution of metamorphic rocks, particularly the poorly preserved prograde metamorphic reactions. The development of new thermodynamic modeling techniques and availability of updated thermodynamic databases and activity–composition (a–X) relations, call for an evaluation of best practices for modeling pressure–temperature (P–T) paths of metabasites. In this paper, eclogite from the Tso Morari UHP terrane, NW India, is used as a representative metabasite to directly compare the outputs (pseudosections and P–T paths) generated from recent versions of the widely used THERMOCALC and Theriak-Domino programs. We also evaluate the impact of using the most updated thermodynamic database (ds 62, Holland and Powell in J Metamorph Geol 29(3):333–383, 10.1111/j.1525-1314.2010.00923.x, 2011) relative to an older version (ds 55, Holland and Powell in J Metamorph Geol 16(3):309–343, 10.1111/j.1525-1314.1998.00140.x, 1998), and the effect of the user’s choice of mineral a–X relations while considering the effect of garnet fractionation on the rock’s effective bulk composition. The following modeling protocols were assessed: (1) TC33; THERMOCALC version 3.33 with database ds 55 and garnet a–X relations of White et al. (J Metamorph Geol 25(5):511–527, 10.1111/j.1525-1314.2007.00711.x, 2007); (2) TC47; THERMOCALC version 3.47 with database ds 62 and garnet a–X relations of White et al. (J Metamorph Geol 32(3):261–286, 10.1111/jmg.12071, 2014a); (3) TDG; Theriak-Domino with database ds 62 and garnet a–X relations of White et al. (2014a), and (4) TDW; Theriak-Domino with database ds 62 and garnet a–X relations of White et al. (2007). TC47 and TDG modeling yield a similar peak metamorphic P–T of 34 ± 1.5 kbar at 544 ± 15 °C and 551 ± 12 °C, respectively. The results are 5–8 kbar higher in pressure than that determined from TC33 modeling (26 ± 1 kbar at 565 ± 8 °C), and TDW modeling (28.5 ± 1.5 kbar at 563 ± 13 °C). Results indicate that all four modeling protocols generally provide consistent metamorphic phase relations and thermodynamic simulations regarding fractionation of the bulk composition and prograde metamorphism within uncertainty. In all model calculations, the initial bulk composition measured by XRF does not represent the effective bulk composition at the time of garnet nucleation. The choice of garnet a–X relations can affect predictions of peak pressure, regardless of program choice. This study illustrates the importance of careful consideration of which a–X relations one chooses, as well as the need for comparison between modeling predictions and evidence from the geochemistry and petrography of the rock(s) themselves.

Ichnologic note: in defence of Thatchtelithichnus Zonneveld, Bartels, Gunnell and McHugh, 2015

Abstract: The validity of the monotypic ichnogenus Thatchtelithichnus has been called into question due to an inference that it is a bioclaustration. Close analysis of the Thatchtelithichnus holmani holotype...

Verbal Quantifiers and Communicating Painkiller Side Effect Risk.

Abstract: The two studies reported here explore the use of verbal quantifiers (e.g., “common”) as an alternative to the numerical presentation of risk information about prescription drugs. Guided by work on ...

A Classroom Study on the Role of Prior Knowledge and Retrieval Tool in the Testing Effect

Abstract: This quasi-experimental study investigated the role of prior psychology knowledge and in-class retrieval activity in the testing effect. Undergraduate introductory psychology students (N = 53) from...

Author Correction: Global status and conservation potential of reef sharks

Abstract: An Amendment to this paper has been published and can be accessed via a link at the top of the paper.

Video Killed the Writing Assignment

Abstract: An introductory Astronomy survey course is often taken to satisfy a college graduation requirement for non-science majors at colleges around the United States. In this course, material that can be broadly categorized into topics related to "the sky", "the Solar System", "the Galaxy", and "cosmology" is discussed. Even with the wide variety of topics in these categories, though, students may not be 100% interested in the course content, and it is almost certain that a specific topic about which a student wishes to learn is not covered. To at least partly address these issues, to appeal to all of the students in this class, and to allow students to explore topics of their choice, a video project has been assigned to students at Albion College as a class activity. In this assignment, students are asked to create a video of a famous (or not) astronomer, astronomical object or discovery, or telescope observatory to present to the class. Students work in pairs to create a video that is original and imaginative and includes accurate scientific content. For this project, then, students use a familiar technology and exercise their creativity while learning a little (or a lot of) science along the way. Herein data on types and topics of videos, examples of videos, assignment requirements and grading rubrics, lessons learned, and student comments will be discussed and shared.

The Professoriate in Liberal Arts Colleges: Early Career Faculty Socialization and Learning

Abstract: The majority of PhD recipients earn their degree in research universities in which the primary focus of doctoral training is on research. Yet, scholars have revealed that such training is inadequate for the myriad academic roles faculty members engage in or for the variety of institution types in which newly minted PhDs earn faculty appointments. The focus of this chapter is on the socialization of early career faculty members in liberal arts colleges (LACs). Specifically, it relies on socialization as well as and career cycles and learning frameworks applied to analysis of data from a longitudinal, mixed methods study (Initiative for Faculty Development in Liberal Arts Colleges) to explore the applicability and extendibility of the Weidman et al. (Socialization of graduate and professional students in higher education: A perilous passage? ASHE-ERIC higher education report, 28. San Francisco: Jossey-Bass. https://files.eric.ed.gov/fulltext/ED457710.pdf, 2001) socialization framework to the early career faculty experience. Findings are shared from the IFDLAC study to provide more insights into the early career faculty experience in LACs which supports an extension of the Weidman et al. socialization framework to the early career faculty experience. The chapter includes recommendations and implications on how to effectively socialize faculty into new environments.

Relationships Between Organic Matter Contents and Bacterial Hydrolytic Enzyme Activities in Soils: Comparisons Between Seasons

Abstract: Microbial assemblages in terrestrial environments, such as soils, utilize hydrolytic enzymes to function biologically in various environments including for the degradation of organic carbon compounds and cycling of nutrients that eventually contributes to the ecological and agricultural productivity of such environments. In this study, 3 soil types (i.e., sandy, loamy and clayey) with varying characteristics were collected within the premises of Albion College in Michigan, with the goal of comparing the occurrences of indigenous bacterial populations and their respective hydrolytic enzyme activities in the soils. The soils were examined for their organic matter content (% OM), while bacterial abundance was determined by combinations of viable counts and nucleic acid staining, and enzymatic activities measured using fluorescein diacetate (FDA) analysis. Results from the study showed loamy soil to have a significantly higher % OM at 30% on average as compared to 2.5% and 6.6% recorded in the sandy and clayey soils. Comparatively, bacterial numbers (both viable and total counts) were also significantly higher in loamy soils than the other two soils. The same trend was observed for FDA analysis with higher fluorescein released in the loamy soil relative to the two other soils. Overall, clear differences were observed in the relationships between % OM and bacterial numbers and hydrolytic enzyme activities among the three soil types and between the two seasons examined. The results suggest that % OM strongly influences both bacterial abundance and hydrolytic enzyme activities in loamy soil and less so in both sandy and clayey soils examined in the study. This study in conclusion revealed potential strong relationships between soil organic carbon and indigenous bacterial populations as well as their FDA activities in various soil types.

Objects, Storytelling, Memory and Living Histories: Curating Islamic Art Empathically in an Era of Trauma and Displacement

Abstract: The recent global surge of public- and museum-initiated interest in Islamic art has been interpreted broadly as having a direct correlation with diplomatic imperatives. Since the onslaught of the so-called migrant crisis, German institutions, in particular, have sought to socially engage refugees with the existing collections of Islamic arts and artefacts in Germany. But how can museums showcase and contextualise the arts of Islamic lands across time and space, in a way that is attentive to the traumatic experiences of displacement, migration and forced exile? In assessing various integrationist and assimilationist discourses, this chapter seeks to examine the gravity and consequences of museums’ pivotal role in providing an empathic and dignified space in society, where it is otherwise absent.

Grit-passion and grit-perseverance in ultramarathon runners

Abstract: The purpose of this study was to investigate the relationship between ultramarathon running, grit-passion, and grit-perseverance A total of 153 ultramarathon runners (age = 405 ± 90 years) answered demographic questions and completed a survey measuring subcomponents of grit via Google Forms Grit was measured with the 12-item Grit Scale consisting of two subscales: consistency of interest (grit-passion) and perseverance of effort (grit-perseverance) The ultramarathon runners were recruited through emails from race directors, Facebook groups, and email invitations from the primary investigator Statistical analyses were performed using Pearson product-moment correlations and a one-way ANOVA Significance was set to p < 05 There was a positive correlation between number of years running and grit-passion ( r = 17, p = 039) On average, participants had spent 144 ± 98 years running and had competed in ultramarathons for 43 ± 35 years A positive correlation was found between the number of kilometres run per week and grit-passion ( r = 22, p = 007) Participants, on average, ran 579 ± 214 kilometres per week For grit-perseverance, there was a statistically significant difference between the short and medium distance groups of ultramarathon runners when compared to the group of runners completing timed ultramarathon races ( p = 002) Failure to complete their last ultramarathon was not significantly associated with grit-passion ( p = 37) or grit-perseverance ( p = 92)

Cometary glycolaldehyde as a source of pre-RNA molecules

Abstract: Over 200 molecules have been detected in multiple extraterrestrial environments, including glycolaldehyde (C2(H2O)2, GLA), a two-carbon sugar precursor that has been detected in regions of the interstellar medium. Its recent in situ detection on the nucleus of comet 67P/Churyumov-Gerasimenko and via remote observations in the comae of others, provides tantalizing evidence that it is common on most (if not all) comets. Impact experiments conducted at the Experimental Impact Laboratory at NASA's Johnson Space Center have shown that samples of GLA and GLA mixed with montmorillonite clays can survive impact delivery in the pressure range of 4.5 GPa to 25 GPa. Extrapolated to amounts of GLA observed on individual comets and assuming a monotonic impact rate in the first billion years of solar system history, these experimental results show that up to 10^23 kg of cometary GLA could have survived impact delivery, with substantial amounts of threose, erythrose, glycolic acid, and ethylene glycol also produced or delivered. Importantly, independent of the profile of the impact flux in the early solar system, comet delivery of GLA would have provided (and may continue to provide) a reservoir of starting material for the formose reaction (to form ribose) and the Strecker reaction (to form amino acids). Thus, comets may have been important delivery vehicles for starting molecules necessary for life as we know it.

A Game-theoretic analysis on the economic viability of mobile content pre-staging

Abstract: The rapid growth of demand for data in wireless communications has driven the mobile service carriers and the research community to seek both effective technical and alternative solutions to the data demand problem. One particular solution, content pre-staging, tries to push content as close to the mobile device as possible in order to lower demand at peak times. Assuming the interesting case that mobile device storage could be made available as part of the mobile carrier’s system capacity either directly by the end user or indirectly by the carrier, this paper investigates the potential economic impacts on the mobile service business and various stakeholders of content pre-staging. We explore the economic implications of content pre-staging by modeling the interplay among the mobile carrier, end users, and the content provider in a game theoretic framework. The carrier designs pricing mechanisms to affect the behaviors of the content provider and end users for the purpose of profit maximization. In particular, two prices are introduced, the price charged to the content provider to pre-stage content on mobile device storage, and the monetary reward to compensate users for the usage of their mobile device storage. Although the individual incentive of the carrier is not necessarily aligned with social incentives, the welfare analysis of content pre-staging shows that the practice improves social welfare by increasing network efficiency. Localizing content increases the overall profitability of mobile service business which is positively related to the relevance of the pre-staged content. The carrier’s pricing mechanisms determine the manner in which the increased profitability of the business is shared by various interested parties. While the carrier may design prices strategically to retain a larger share of the increased profitability, content pre-staging can benefit all the three parties in the game, i.e., the carrier gains in saved capacity and new revenue, users gain QoE, content, and financial rewards for sharing mobile device storage, and the content provider gains in increased revenue from increased content access.

Funny “haha” or Funny because I’m Black? Assessing Viewers’ Reactions to Chappelle’s Show

Abstract: For years, Dave Chappelle has maintained that the reason he walked away from his eponymous show, and a $50 million dollar contract, was his realization that people were laughing at him, not with hi...

Connection blocking in $$\text {SL}(n,\mathbb {R})$$ SL ( n , R ) quotients

Abstract: Let G be a connected Lie group and $$\varGamma \subset G$$ a lattice. Connection curves of the homogeneous space $$M=G/\varGamma $$ are the orbits of one parameter subgroups of G. To block a pair of points $$m_1,m_2 \in M$$ is to find a finite set $$B \subset M{\setminus } \{m_1, m_2 \}$$ such that every connecting curve joining $$m_1$$ and $$m_2$$ intersects B. The homogeneous space M is blockable if every pair of points in M can be blocked. In this paper we investigate blocking properties of $$M_n= \text {SL}(n,\mathbb {R})/\varGamma $$ , where $$\varGamma =\text {SL}(n,\mathbb {Z})$$ is the integer lattice. We focus on $$M_2$$ and show that the set of non blackable pairs is a dense subset of $$M_2 \times M_2$$ , and we conclude manifolds $$M_n$$ are not blockable. Finally, we review a quaternionic structure of $$\text {SL}(2,\mathbb {R})$$ and a way for making co-compact lattices in this context. We show that the obtained quotient homogeneous spaces are not finitely blockable.