bluuebunny/crossref_metadata_2025 huggingface dataset:
Non-fluorine surface modification of acetylated birch for improved water repellence
Authors: Yin Haiyan , Sedighi Moghaddam Maziar , Tuominen Mikko , Dėdinaitė Andra , Wålinder Magnus , Swerin Agne
Published: April 2021

In this work, a non-fluorinated surface treatment, i.e., hydrophobized silicone nanofilaments, was applied on both birch and acetylated birch wood samples via a gas-phase based reaction. A superhydrophobic behavior was observed on both the surface-modified samples as revealed by the static water contact angles (CAs) greater than 160°, also valid for samples prepared with the shortest reaction time of 1 h. The dynamic wettability behavior of the samples was studied by a multicycle Wilhelmy plate method. The surface-modified acetylated birch exhibited a pronounced enhanced water resistance, resulting in very low water uptake of 3 ± 1 wt% after 100 cycles, which was not only about 29 and 5 times lower than that of the non-surface-modified birch and acetylated birch, respectively, but also three times lower than that of the surface-modified birch. Moreover, the aesthetic appearance of the acetylated wood was maintained as the surface modification only resulted in a small color change. This work shows the potential of preparing super water-repellent wood by non-fluorinated surface modification.
A numerical study on combined baffles quick-separation device
Authors: Dehdarinejad Ehsan , Bayareh Morteza , Ashrafizaadeh Mahmud
Published: April 2021

The transfer of particles in laminar and turbulent flows has many applications in combustion systems, biological, environmental, nanotechnology. In the present study, a Combined Baffles Quick-Separation Device (CBQSD) is simulated numerically using the Eulerian-Lagrangian method and different turbulence models of RNG k-ε, k-ω, and RSM for 1–140 μm particles. A two-way coupling technique is employed to solve the particles’ flow. The effect of inlet flow velocity, the diameter of the splitter plane, and solid particles’ flow rate on the separation efficiency of the device is examined. The results demonstrate that the RSM turbulence model provides more appropriate results compared to RNG k-ε and k-ω models. Four thousand two hundred particles with the size distribution of 1–140 µm enter the device and 3820 particles are trapped and 380 particles leave the device. The efficiency for particles with a diameter greater than 28 µm is 100%. The complete separation of 22–28 μm particles occurs for flow rates of 10–23.5 g/s, respectively. The results reveal that the separation efficiency increases by increasing the inlet velocity, the device diameter, and the diameter of the particles.
EVA 2.0: Emotional and rational multimodal argumentation between virtual agents
Authors: Rach Niklas , Weber Klaus , Yang Yuchi , Ultes Stefan , André Elisabeth , Minker Wolfgang
Published: April 2021

Persuasive argumentation depends on multiple aspects, which include not only the content of the individual arguments, but also the way they are presented. The presentation of arguments is crucial – in particular in the context of dialogical argumentation. However, the effects of different discussion styles on the listener are hard to isolate in human dialogues. In order to demonstrate and investigate various styles of argumentation, we propose a multi-agent system in which different aspects of persuasion can be modelled and investigated separately. Our system utilizes argument structures extracted from text-based reviews for which a minimal bias of the user can be assumed. The persuasive dialogue is modelled as a dialogue game for argumentation that was motivated by the objective to enable both natural and flexible interactions between the agents. In order to support a comparison of factual against affective persuasion approaches, we implemented two fundamentally different strategies for both agents: The logical policy utilizes deep Reinforcement Learning in a multi-agent setup to optimize the strategy with respect to the game formalism and the available argument. In contrast, the emotional policy selects the next move in compliance with an agent emotion that is adapted to user feedback to persuade on an emotional level. The resulting interaction is presented to the user via virtual avatars and can be rated through an intuitive interface.
Investigating GNSS multipath effects induced by co-located Radar Corner Reflectors
Authors: Fuhrmann Thomas , Garthwaite Matthew C. , McClusky Simon
Published: April 2021

Radar Corner Reflectors (CR) are increasingly used as reference targets for land surface deformation measurements with the Interferometric Synthetic Aperture Radar (InSAR) technique. When co-located with ground-based Global Navigation Satellite Systems (GNSS) infrastructure, InSAR observations at CR can be used to integrate relative measurements of surface deformation into absolute reference frames defined by GNSS. However, CR are also a potential source of GNSS multipath effects and may therefore have a detrimental effect on the GNSS observations. In this study, we compare daily GNSS coordinate time series and 30-second signal-to-noise ratio (SNR) observations for periods before and after CR deployment at a GNSS site. We find that neither the site coordinates nor the SNR values are significantly affected by the CR deployment, with average changes being within 0.1 mm for site coordinates and within 1 % for SNR values. Furthermore, we generate empirical site models by spatially stacking GNSS observation residuals to visualise and compare the spatial pattern in the surroundings of GNSS sites. The resulting stacking maps indicate oscillating patterns at elevation angles above 60 degrees which can be attributed to the CR deployed at the analysed sites. The effect depends on the GNSS antenna used at a site with the magnitude of multipath patterns being around three times smaller for a high-quality choke ring antenna compared to a ground plane antenna without choke rings. In general, the CR-induced multipath is small compared to multipath effects at other GNSS sites located in a different environment (e. g. mounted on a building).
Numerical study of the stock market crises based on mean field games approach
Authors: Trusov Nikolai V.
Published: April 2021

We present an approach to describe the stock market crises based on Mean Field Games (MFGs) and Optimal Control theory with a turnpike effect. The impact of the large amount of high-frequency traders (HFTs) can be modeled via a mean field term. We introduce the turnpike as a function that relies on the changes of the asset share price. An MFG is a coupled system of PDEs: a Kolmogorov–Fokker–Planck equation, evolving forward in time, and a Hamilton–Jacobi–Bellman equation, evolving backwards in time. The ill-posedness of this system comes from a turnpike effect. The numerical solution of an extremal problem that is dual to a PDE system is presented. We apply this approach to describe the Chinese stock market crash in 2015 considering the representative stock of CITIC Securities (ticker 600030). We consider HFTs that form a dominating bull and bear market. As a result, the bull strategy imitators do not make any profit.
Metaphorical thinking in our literary experiences of J.D. Salinger’s “The Catcher in the Rye”
Authors: Rasse Carina , Gibbs Raymond W.
Published: April 2021

This article explores how literary texts, in this case the novel “Catcher in the Rye” by J.D. Salinger, elicit metaphorical thinking as a major part of readers’ interpretive experiences. Our main argument is that metaphorical thinking does not arise only given our encounter with individual verbal metaphors, but emerges in various ways as part of our habitual forms of imaginative metaphorical understandings. Metaphorical thinking is closely linked to embodied simulation processes by which readers project themselves imaginatively into the lives of story characters. Embodied simulation processes capture readers’ rich phenomenological characteristics (e.g., immersion, absorption, transportation) of literary experience. Metaphorical thinking unfolds in hierarchical layers across different time spans during literary reading.
Familial hyperphosphatemic tumoral calcinosis in an unusual and usual sites and dramatic improvement with the treatment of acetazolamide, sevelamer and topical sodium thiosulfate
Authors: Emecen Sanli Merve , Kilic Ayse , Aktasoglu Ekin , Inci Asli , Okur Ilyas , Ezgu Fatih , Tumer Leyla
Published: April 2021

Objectives

Familial hyperphosphatemic tumoral calcinosis is a rare disorder characterized by hyperphosphatemia with recurrent ectopic periarticular calcifications, in addition to other visceral and vascular manifestations, without any inflammatory or neoplastic disorder. The available treatment strategies are limited. Here we report an eight year old female patient with recurrent lesions under the chin, and bilateral hips which are painful and improving of the size of the lesions and hyperphosphatemia.

Case presentation

The patient was started to the treatment with peroral acetazolamide however the lesion did not regress but a new lesion appeared then we added sevelamer and topical sodium thiosulfate treatment for three months. After the three months of the combination treatment the lesions, there were no pain, no hyperphospahtemia regression/disappearance of the lesions.

Conclusions

This combination treatment or topical sodium thiosulfate use only may be a novel treatment strategy for the patients prospective controlled trials are needed.
Asymptomatic pituitary apoplexy induced by corticotropin-releasing hormone in a 14 year-old girl with Cushing’s disease
Authors: Fonseca Liliana , Borges Duarte Diana , Freitas Joana , Oliveira Maria João , Ribeiro Isabel , Amaral Cláudia , Borges Teresa
Published: April 2021

Objectives

Pituitary apoplexy is a rare complication of Cushing’s disease (CD), especially in the paediatric age and even more rarely it can occur following anterior pituitary stimulation tests.

Case presentation

We report a case of a 14-year-old girl who was admitted to our Hospital for evaluation of a possible Cushing’s syndrome (CS). Her symptoms and initial laboratory tests were suggestive of CD. Magnetic resonance imaging (MRI) revealed a microadenoma of the pituitary gland. As part of her evaluation she was submitted to a corticotropin-releasing hormone (CRH) stimulation test. Two and a half months later the patient was re-evaluated and presented with both clinical improvement of CS, biochemical resolution of hypercortisolism and tumour size reduction in the MRI, also evidencing a haemorrhagic component favouring the diagnosis of pituitary apoplexy after CRH stimulation test. The patient denied any episodes of severe headache, nausea, vomiting or visual changes.

Conclusions

To our knowledge, the authors report the first case of a pituitary apoplexy after a CRH stimulation test in the paediatric age.
Oral glucose tolerance response curve predicts disposition index but not other cardiometabolic risk factors in healthy adolescents
Authors: Hoffman Robert P. , Copenhaver Melanie M. , Zhou Danlei , Yu Chack-Yung
Published: April 2021

Objectives

In obese adults the shape of the glucose response curve during an oral glucose tolerance test (OGTT) predicts future type 2 diabetes. Patients with an incessant increase or monophasic curves have increased risk compared to those with biphasic curves. Since type 2 diabetes is associated with increased cardiometabolic risk, we studied whether differences in OGTT response curve are associated with differences in cardiometabolic risk factors in healthy adolescents across a wide body mass index (BMI) range.

Methods

Sixty-nine (33F/36M), white adolescents (age: 15.2 ± 1.7 years; BMI: 21.5 ± 4.7 kg/m2; mean ± SD) were studied. Risk factors measured included percent body fat, blood pressure, lipids, augmentation index, reactive hyperemia, endothelin 1, plasminogen activator 1, inflammatory markers (interleukin 6, c-reactive protein), insulin secretion, insulin sensitivity (Matusda index), and disposition index (DI).

Results

Thirty-two subjects had biphasic responses; 35 subjects had monophasic responses and two females had incessant increases. Sex did not affect the frequency of responses. Glucose area under the curve during OGTT was greater in those with a mono vs. biphasic curves (p=0.01). Disposition index was markedly lower in subjects with a monophasic curve than in those with a biphasic curve (3.6 [2.3–5.0] vs. 5.8 [3.8–7.6], median [25th, 75th%] p=0.003). Triglyceride to high-density lipoprotein cholesterol (HDL) ratio was higher in subjects with a monophasic curve (p=0.046).

Conclusions

The decreased disposition index indicates that in healthy adolescents a monophasic response to OGTT is due to decreased insulin secretion relative to the degree of insulin resistance present. This was not associated with differences in most other cardiometabolic risk markers.

Trial registration

Clinical Trials.gov, NCT02821104.
Invisible burden of COVID-19: enzyme replacement therapy disruptions
Authors: Kahraman Ayça Burcu , Yıldız Yılmaz , Çıkı Kısmet , Akar Halil Tuna , Erdal İzzet , Dursun Ali , Tokatlı Ayşegül , Sivri Hatice Serap
Published: April 2021

Objectives

Lysosomal storage diseases (LSD) constitute an important group of metabolic diseases, consisting of approximately 60 disorders. In some types of lysosomal diseases, enzyme replacement therapy (ERT) is administered intravenously in weekly or biweekly doses. Unfortunately, scheduled ERT during COVID-19 was disrupted. We considered the possibility of adverse outcomes caused by the disruption in the treatment of patients with lysosomal storage disorders.

Methods

During the COVID-19 pandemic, we conducted a questionnaire that was delivered via Internet to assess how this vulnerable patient group was affected by the pandemic in terms of their access to treatment and their disease-related symptoms.

Results

The questionnaire was filled out by 75 patients. There were 35 patients whose treatment dose was missed because of COVID-19. The most common reason for skipping treatment was not wanting to go to the hospital for fear of contracting COVID-19. These 35 patients missed a median of four doses of ERT (range: 1–16 dosages). Twenty-one patients (60%) claimed that they were affected physically by not taking ERT (20 mucopolysaccaridoses, 1 Fabry disease), whereas 14 (40%) did not.

Conclusions

Interruption of ERT during the COVID-19 pandemic may have significant consequences. It may be beneficial to switch to home treatment or reserve dedicated facilities. With proper planning and management, the treatment disruptions of this particular group can be avoided.
Effect of anthropogenic activity on mammal activity patterns in two ecosystems
Authors: Pérez-Irineo Gabriela , Hernández-Sánchez Alejandro , Santos-Moreno Antonio
Published: April 2021

Adaptations in species activity patterns allow animals to avoid risks generated by human activities and domestic and feral species. We aimed to evaluate the effect of anthropogenic activity on mammal activity patterns in two tropical ecosystems -semi-evergreen forest and cloud forest-, and its temporal variation in the Sierra Norte of Oaxaca, Mexico. We expected mammal activity patterns to show significant differences from activity patterns of humans and domestic species. From July 2014 to June 2015, we placed camera traps in 23 sites in a semi-evergreen forest and 23 sites in a cloud forest. We estimated the activity level of each species and calculated the activity overlap between wild species and humans and domestic species in each season. We recorded a total of 16 species of wild mammals, four domestic species, and obtained 738 human records. We found no evidence of an effect of anthropogenic activity on the activity patterns of wild mammals: we found similar activity levels between seasons and ecosystems, and moderate to high overlap between the activity patterns of some wild mammal species and of humans and domestic species. Low human population density, human activity temporal dynamics, and the plasticity of wild species could explain the results of our study.
Altitude, shading, and management intensity effect on Arabica coffee yields in Aceh, Indonesia
Authors: Anhar Ashabul , Abubakar Yusya , Widayat Heru Prono , Muslih Ali Muhammad , Romano  , Baihaqi Akhmad
Published: April 2021

The productivity of Arabica coffee in the Gayo Highlands, Aceh, Indonesia is far below its potential because of climate change and inadequate agricultural practices. To develop a strategy on sustainable coffee yield and improvements of smallholder farming systems, we investigated coffee productivity in three classes of shade densities and three classes of total management intensities index (TMI) along six altitude gradients (1,000–1,600 m above sea level) over 234 farmers’ plots. Coffee productivity was significantly affected by altitude, shade density, and TMI. Our results showed a stronger positive altitudinal effect with coffee productivity in middle and higher altitudes than in lower altitudes and were related to shade density and TMI. Increasing elevation of coffee plantation from lower to middle altitudes and shade from low to medium density increased in coffee productivity but further increase to higher altitude seemed to depress coffee productivity. Increasing TMI positively increased coffee productivity across altitudes. Shade density and TMI played significant roles in coffee productivity in lower altitudes; therefore, coffee farmers have to increase the shade to medium or higher density and at the same time improve plantation management to medium or high TMI.
Clinical significance of serum homocysteine as a biomarker for early diagnosis of diabetic nephropathy in type 2 diabetes mellitus patients
Authors: Ye Bin , Zhu Xiangying , Zeng Zhifu , Ji Xiaozhen , Ji Meixia
Published: April 2021

Objective

The aim of this study was to investigate the clinical significance of serum homocysteine (Hcy) as a biomarker for early diagnosis of diabetic nephropathy (DN) in type 2 diabetes mellitus (T2DM) patients.

Methods

Fifty-five T2DM patients with DN and 51 T2DM patients without DN were prospectively recruited from January 2016 to May 2020 in our hospital. The serum Hcy was tested by electrochemiluminescence assay in DN and T2DM groups and compared. The diagnostic efficacy of serum Hcy as a biomarker for early diagnosis of DN was evaluated by calculating the diagnostic sensitivity, specificity and area under the ROC curve (AUC).

Results

The serum levels of Hcy were 15.49 ± 5.40 and 9.23 ± 3.15 μmol/L for DN and T2DM patients, respectively, with statistical difference (t = 7.21, P < 0.001). In the DN group, the serum Hcy levels for patients with hyperfiltration, intermittent proteinuria, microalbuminuria, macroalbuminuria and uremic were 10.99 ± 2.57, 13.90 ± 2.86, 15.38 ± 4.77, 18.98 ± 4.36 and 23.31 ± 5.22 μmol/L, respectively, which indicated that serum Hcy levels in DN were higher than those of T2DM patients and correlated with patient’s renal damage. Using the serum Hcy level as the reference, the diagnostic sensitivity, specificity and AUC were 84.31 (71.41–92.98)%, 74.55 (61.00–85.33)% and 0.85 (0.78–0.92)%, respectively, with the cutoff value of 12.08 between DN and T2DM. The serum Hcy also had relatively good differential diagnostic efficacy between different DN stages with high sensitivity, specificity and AUC.

Conclusion

Serum Hcy was obviously elevated in DN compared to T2MD and correlated with the renal damage severity, which can be applied as a potential serological marker for early diagnosis of DN.
Stability of stochastic differential equations driven by multifractional Brownian motion
Authors: El Barrimi Oussama , Ouknine Youssef
Published: April 2021

Our aim in this paper is to establish some strong stability results for solutions of stochastic differential equations driven by a Riemann–Liouville multifractional Brownian motion. The latter is defined as a Gaussian non-stationary process with a Hurst parameter as a function of time. The results are obtained assuming that the pathwise uniqueness property holds and using Skorokhod’s selection theorem.
Migration as a Factor of the Development: from the global openness to the local barriers
Authors:   MGIMO University, Apanovich Maria
Published: April 2021

The global problem of food security and access to quality products is of great importance not only for the local communities, but also for migrants. The study focuses on the agricultural and food policy of the European Union, which seeks to become “greener” and eliminate the abundance of nitrates and pesticides that are harmful to human health. At the same time, the issue of interaction and penetration of the migrants’ dietary traditions and their “ethnic cuisine” into the societies of the host countries arises. Food habits do not always have exceptional “usefulness”, but in light of cooperation between countries and the influx of migrants from different cultures, it has become a “norm” or “tradition”. The article provides a comparative analysis of the global trend of openness with local trends in the projection of “protective barriers”, in particular for the migration community. Cooperation between European countries should play a key role in maximizing the positive impact of migration. It is important to highlight the very strong links that exist between food security, agriculture and rural development, other sectors of development cooperation
Political Shifts in Latin America and the Problems of Relations with the EU
Authors:   Institute of Latin America, Russian Academy of Sciences., Iwanowski Zbiegnew
Published: April 2021

The article explores the economic and social situation in Latin America after the «golden decade» (2003–2013) and political shifts in the region. During the last electoral cycle, the region witnessed a certain political landscape transformation, including the «right drift» on the one hand and the strengthening of the positions of the left forces on the other. Thus, political polarization at the national and regional levels sharply increased, integration blocks have disintegrated or are in crisis. As a result, the region is no longer a «unity in diversity». The author highlights the reasons for the intensification of European politics in Latin America. Although the economy remains a priority in interregional cooperation, political aspects are becoming increasingly important. Both regions actively cooperate in solving global problems, but their priorities differ significantly. The European Union cooperates with Latin America in strengthening multilateralism and improving global governance, both partners try to reform international institutions, reject protectionism and underline the priority of international law.
The Image of the Second World War as a Factor in the Formation of Contemporary European Identity
Authors:   Siberian Law University, Denisov Yuri
Published: April 2021

The image of the Second World War is one of the most significant images of the past for the European identity. The purpose of this study is to analyze its potential for the formation of the modern European identity as a supranational construct. The ambivalent nature of this phenomenon is revealed. The image WWII contains a sufficiently powerful unifying impulse. It is determined by the uniting role of the colossal tragedy, the common misfortune that befell Europe in the middle of the past century, its integrational significance for the joint efforts to build a single European community in order to prevent the recurrence of these events. Nowadays, this momentum is realized through the preservation of European memory, the institutionalization of anniversaries, the broadcast of the memory of the war in the process of intergenerational communication in the functioning of the institutions of education and cultural environment as a whole, the articulation of traumatic memories in the political discourse. At the same time the author demonstrated that, the image of WWII has a serious deconsolidating element for the common European identity. It is caused by contradictions in the European collective memory. The new technological revolution that has engulfed Europe, accompanied by a steady shift of communication practices into cyberspace and the emergence of the phenomenon of cyber-memory, changes the mechanisms of representation and reception of the war image. The Global Network facilitates a steady increase of both the means for the representation and visualization of the image of the past, making it more interactive, multimodal, multifaceted and simplified. The number of actors of memory politics, who take part in the formation of the European identity, or rather ‒ of an unlimited set of identities has been growing.
The Values of the EU and their Protection in the European Law
Authors:   Primakov National Research Institute of World Economy and International Relations, Russian Academy of Sciences, Kuvaldin Stanislav
Published: April 2021

Article 7 of the Treaty on the European Union envisages a mechanism for responding to breaching by Member States the values of democracy, equality, the rule of law and human rights proclaimed by the Union, as well as the introduction of sanctions. Nevertheless, the EU structures are extremely cautious about this mechanism, despite the reasons for its application. The article analyzes the history of this clause in European legislation and the first attempts to influence dubious decisions of the Member States. The author explores the cases of Poland and Hungary in light of discussions to initiate the Article 7 procedures against these countries. It is concluded that such an outcome is unlikely. It is highlighted that the clause was deliberately formulated so that it allows to limit the actions of European institutions, to leave decisions in the hands of national governments and to provide an opportunity to settle the disput through negotiations. The author explores the internal discussions of alternative ways to influence values-violating Member States.
Highlighting Numbers
Authors: Author Anonymous
Published: April 2021

This autoethnography explores the communication and helpful/hindering systems available for faculty being harassed and stalked by current or former students. Highlighting general statistics and the numbers in my own student-stalker experience, I use this work to elucidate socio-psychological reports and qualitative accounts of stalking experiences, while integrating my own background and identity ambivalence as a combined woman, educator, and stalking victim. Last, I offer implications and practical insights regarding support for faculty within the university and criminal justice systems.
Giving an Account of One’s Current Self
Authors: Booth E. Tristan , Spencer Leland G.
Published: April 2021

Transgender individuals often face a barrage of questions from family, friends, medical professionals, and others, asking them to account for and explain their identities. Ultimately, these questions all come down to one fundamental concern: “Why do you feel this way?” This essay offers one potential answer. By turning to the philosophical concept of reincarnation through the methodological approach of autoethnography, this essay posits a relationship among past lives and current lives as one potential way of accounting for one author’s (trans) identity. We present an exploration of one author’s identity in the form of a dialogue with the other author, a supportive friend curious about his interlocutor’s beliefs in reincarnation and excited to learn.
The Scoutmaster’s Son
Authors: Dooling David
Published: April 2021

Using a blend of auto-archaeological, critical, and queer approaches, I descriptively and performatively articulate the position of my sexual identity when entrenched in the familial and organizational structures of scouting. Throughout this piece, I expose the intersections of father-son turmoil and organizational oppression along with offering defiant modes of queer resistance(s) and becoming(s).
“Beautiful, If You See It the Right Way”
Authors: Toth Leah
Published: April 2021

David Lynch’s first feature film, Eraserhead, is considered by many to be his strangest, due to its dark industrial imagery and dissonant sound design. This essay examines the function of audible noise in Eraserhead within the context of 1970s deindustrialization and argues that noise is a key but overlooked element of the film’s overall aesthetic design—an homage to the sounds and imagery of a fading and faded industrialized United States. Listening closely firmly establishes this impression: The sound design contributes substantially to the film’s synchretic surrealism, and its ambiguity through multilayered mechanical sound highlights listeners’ interpretive practices, particularly in comparison to most films’ use of a soundtrack to dictate rather narrowly an audience’s emotional response. Gaps between what audiences hear and what they see in Eraserhead create a void strongly suggestive of loss and longing—an impression Lynch, though often reticent about his work, has indicated in many interviews over the decades. Though many studies address the fact of the film’s innovative sound design, few examine it closely in relation to its narrative and visual elements within any sort of historical context or within Lynch’s deeply idiosyncratic aesthetic sensibility. In so doing, this essay not only highlights Lynch’s remarkably consistent aesthetic but also stresses why and how Eraserhead’s sound design is an outlier, opening up, as it does, the expressive possibilities in an unconventionally noisy soundtrack.
Listening to the Democratic Forest with Brian Harnetty
Authors: Cummings Alex Sayf
Published: April 2021

Sound artist Brian Harnetty talks about his Forest Listening Rooms project and reflects on the politics of building interactive, immersive conversations about people and the landscapes that surround them in Appalachia, as well as the artistic and philosophical influences on his unique approach to composition.
Cryopreservation of Canine Erythrocytes Using Dimethyl Sulfoxide, Polyethylene Glycol and Sucrose
Authors:   Kharkiv State Zooveterinary Academy, Denysova Оlga , Zhegunov Gennadiy ,   Kharkiv State Zooveterinary Academy
Published: April 2021

Cryoprotective properties of combined media of permeable (dimethyl sulfoxide) and impermeable (polyethylene glycol with m. w. 1500) cryoprotective agents during rapid cooling in liquid nitrogen of canine erythrocytes using saline and sucrose-saline media have been investigated. It was found that the use of combined solutions of cryoprotective agents based on polyethylene glycol with m.w. 1500 (15%) and dimethyl sulfoxide (2.5–10%) in saline was not quite effective for cryopreservation of canine erythrocytes. Reducing the salt concentration and adding cell-impermeable sucrose to the cryopreservation medium increase the preservation of erythrocytes after warming. The best cryoprotective properties for canine erythrocytes were demonstrated by 10% dimethyl sulfoxide based on sucrose-saline medium, with high preservation of cells after freeze-warming, mechanical and osmotic stability of warmed erythrocytes. This indicates the possibility of a long-term storage and use of cryopreserved canine erythrocytes for transfusions.
Application of Vacuum Infiltration in Cryopreservation of Isolated Grape Buds
Authors:   Institute for Problems of Cryobiology and Cryomedicine of the National Academy of Sciences of Ukraine, Kharkiv, Prystalov Anton , Bobrova Olena ,   Institute for Problems of Cryobiology and Cryomedicine of the National Academy of Sciences of Ukraine, Kharkiv, Kuleshova Larisa ,   Institute for Problems of Cryobiology and Cryomedicine of the National Academy of Sciences of Ukraine, Kharkiv, Ukraine
Published: April 2021

Preserving the gene pool of grapes, referred to the vegetatively propagated plants is a complicated task, which can be also solved by cryopreservation of the buds. To saturate such bulk and heterogeneous samples with cryoprotectants the novel methods are required. The effectiveness of vacuum infiltration and 60 min standard passive saturation (soaking) of isolated grape buds of the Russian Concord variety with a cryoprotective solution PVS 2 were compared in this research. To saturate by vacuum infiltration the buds were incubated in cryoprotective solution for 15 min at 40 kPa, afterwards, the pressure was gradually increased to atmospheric level. The efficiency of bud saturation was evaluated with low-temperature differential scanning calorimetry by changing the enthalpies and temperatures of phase transitions as well as the intensity of heat capacity jump at glass transition. The use of vacuum in the saturation of isolated grape buds were found to lead to a strong rise in cryoprotectant concentration in them and a significant decrease in the amount of free water crystallized during cooling compared to passive soaking in a PVS 2 vitrification solution.
Isolation of Human Dental Pulp Stem Cells and Their Characteristics Before and After Cryopreservation
Authors:   Institute for Problems of Cryobiology and Cryomedicine of the National Academy of Sciences of Ukraine, Kharkiv, Mazur Svitlana , Rogulska Olena ,   Institute for Problems of Cryobiology and Cryomedicine of the National Academy of Sciences of Ukraine, Kharkiv, Revenko Olena ,   Institute for Problems of Cryobiology and Cryomedicine of the National Academy of Sciences of Ukraine, Kharkiv, Ukraine, Volkova Nataliya ,   Institute for Problems of Cryobiology and Cryomedicine of the National Academy of Sciences of Ukraine, Kharkiv, Ukraine, Petrenko Oleksandr ,   Institute for Problems of Cryobiology and Cryomedicine of the National Academy of Sciences of Ukraine, Kharkiv, Ukraine
Published: April 2021

Dental pulp stem cells (DPSCs) from human third molar tooth germ (wisdom tooth) were isolated using a collagenasebased enzymatic method, the obtained cells were analyzed as for morphology in monolayer culture, immunophenotype, proliferation and differentiation potential before and after cryopreservation. In this study, we showed that based on morphological features, surface markers profile and differentiation potential, the isolated DPSCs corresponded to multipotent mesenchymal stromal cells. DPSCs cryopreservation by slow cooling (1 °С / min) down to –80°C with subsequent immersion into liquid nitrogen in cryoprotectant-free culture medium led to cell death. Cryopreservation using the same protocol in the presence of 10% dimethyl sulfoxide (DMSO) and 20% serum ensured (82 ± 6)% cell viability; while metabolic and proliferative activity, as well as the ability to differentiate into the osteo- and adipogenic lineages of cryopreserved DPSCs were similar to their non-cryopreserved counterparts.
Post-Cryo Survival of Rat Testicular Interstitial Cells in Hydroxyethyl Starch-Based Media
Authors:   Institute for Problems of Cryobiology and Cryomedicine of the National Academy of Sciences of Ukraine, Kharkiv, Pakhomov Oleksandr
Published: April 2021

The development of cryoprotective serum-free or xeno-free media is required for safe use of cryopreserved testicular material for transplantation. In this study, the solutions containing 10% fetal bovine serum (FBS) or 5 mg/ml bovine serum albumin (BSA) did not significantly enhance the general survival of interstitial cells (ICs) after cryopreservation but increase their metabolic activity and steroid producing cell (HSD+-cells) survival. The use of 50 and 100 mg/ml hydroxyethyl starch (HES) in DMSO-based cryoprotective solutions instead of BSA or FBS enabled the improvement of the IC general survival and the survival of HSD+-cells. The use of HES supplemented media allowed to decrease the dimethyl sulfoxide (DMSO) concentration from 1.4 to 0.7 M and to preserve the amount and metabolic activity of ICs. Thus, designing cryoprotective media containing DMSO and HES can facilitate the formulation of serum-free solutions for cryopreservation that in turn paves a way for implementation of the use of cryopreserved material for practical medicine.
Isolation and Cryopreservation of Placental Cells: Search for Optimal Biotechniques in Experimental and Regenerative Medicine
Authors:   Institute for Problems of Cryobiology and Cryomedicine of the National Academy of Sciences of Ukraine, Kharkiv, Prokopiuk Olga , Shevchenko Mariia ,   Institute for Problems of Cryobiology and Cryomedicine of the National Academy of Sciences of Ukraine, Kharkiv, Prokopiuk Volodymyr ,   Institute for Problems of Cryobiology and Cryomedicine of the National Academy of Sciences of Ukraine, Kharkiv, Ukraine, Musatova Irina ,   Institute for Problems of Cryobiology and Cryomedicine of the National Academy of Sciences of Ukraine, Kharkiv, Ukraine, Safonov Roman ,   Kharkiv National Medical University, Prokopiuk Oleksandra ,   Kharkiv Academy of Postgraduate Education
Published: April 2021

High efficacy of placental cells application necessitates their investigation. Preclinical studies require an improvement of the methods for obtaining, standardizing and storage of placental cells of experimental animals. Cells were isolated from rats and mice placentas by means of different enzymatic methods and the one of explants. Cells were cryopreserved with DMSO in DMEM using two-stage freezing. The number, morphological, cultural, metabolic features of cells were studied after isolation and storage. The maximum number of viable cells from the placentas of mice and rats was found to be obtained using the explant method or trypsin with ETDA. Cell cultures from mice and rats placentas after the third passage had stable morphofunctional characteristics. The viability of warmed rat placental cells according to dye exclusion was (92.3 ± 1.6)%, according to the adhesive test this was (81.3 ± 5.8)%. For mice placental cells, these values were (86.7 ± 3.7)% and (79.2 ± 8.1)%, correspondingly. The research results enabled the determining of effective biotechniques for obtaining the cryopreserved placental cells of rats and mice to perform preclinical studies of their biological effect in models of allo- and autotransplantations.
Áfidos (Hemiptera: Aphididae) de Colombia, con nuevos registros para el norte de Sudamérica
Authors: Simbaqueba Ronald , Serna Cardona Francisco Javier
Published: April 2021

Los áfidos son insectos importantes en la agronomía por alimentarse de la savia de plantas cultivadas. Sus daños pueden generar pérdidas económicas y llegar a ser letales para las plantas, debido las enfermedades que se desarrollan por los virus que ellos transmiten. A pesar de esta importancia, los inventarios taxonómicos en Colombia son aún incipientes. Además, las especies relacionadas en estudios anteriores no están representadas por especímenes conservados en colecciones, lo cual dificulta hacer corroboraciones taxonómicas. En el presente trabajo, se enriqueció el conocimiento de las especies de áfidos para el país y se generaron registros nuevos de especies para el norte de Sudamérica. La mayoría de las muestras proviene directamente de campo y algunas de museos del país. Se estudiaron 1400 especímenes que se integraron al Museo entomológico Universidad Nacional Agronomía Bogotá (UNAB). Se ofrece una clave taxonómica para 42 especies, las diagnosis e ilustraciones para 27 especies y una lista de 51 hospedantes botánicos. Eulachnus rileyi, Greenidea psidii, Wahlgreniella nervata, Neomyzus circumflexum, Myzus ascalonicus,Illinoia morrisoni y Ovatus crataegarius se registran por primera vez para el país.
Tasa de defecación del Temazate rojo (Mazama temama) en cautiverio
Authors: Romero-Castañón Salvador , Villarreal Román Gabriela , Villarreal Espino-Barros Oscar , Molina-Martínez Arcangel
Published: April 2021

El temazate rojo (Mazama temama) es uno de los cérvidos más abundantes y con más amplia distribución en los bosques neotropicales. Un método para estimar densidades poblacionales es mediante el conteo de heces, para lo cual es necesario conocer la tasa de defecación. Para obtener dicha tasa en este ungulado, se realizaron conteos de los eventos de defecación, durante cuatro días, en tres individuos adultos: dos hembras y un macho; alojados en cautiverio en el parque Xcaret, ubicado en el estado de Quintana Roo, México. La tasa de defecación promedio obtenida fue de 10 ± 3,33 (DE) grupos de excrementos/individuo/día. Este dato permitirá realizar estimaciones de densidad poblacional de esta especie en vida libre.
Composición y estructura de comunidades asociadas de pino-izotal (Pinus pseudostrobus-Nolina parviflora), en Puebla, México
Authors: Pompa-Castillo Eduardo Fernando , Luna-Cavazos Mario , García-Moya Edmundo
Published: April 2021

El análisis de la estructura y flora de las comunidades vegetales permite conocer las interrelaciones de la comunidad con su entorno. En Puebla, México, existen comunidades vegetales compuestas de pino e izotal, por lo que surge la pregunta ¿Cuál es la similitud o diferencia florística entre ambos tipos de vegetación que se encuentran en áreas cercanas? El objetivo fue analizar la estructura de la vegetación con base en la riqueza y semejanza florística en el pinar e izotal para contribuir al conocimiento de la diversidad de este tipo de comunidades vegetales. Se establecieron unidades de muestreo (UM) de 1000 m2, 16 m2 y 1 m2 para el estrato alto, medio y bajo respectivamente. Se registraron las especies y se estimó la densidad, dominancia y frecuencia, para calcular el Índice de Valor de Importancia. Se calculó el índice de diversidad de Shannon-Wiener y el de diversidad verdadera. La semejanza florística se estimó mediante análisis de agrupamiento; la asociación de especies y UM con ordenación por el índice Bray-Curtis. La riqueza florística en el pinar fue de 79 especies y en izotal 86; el índice de Shannon fue 1,47 y 1,34, respectivamente y fueron significativamente diferentes; el de diversidad verdadera 4,34 y 3,81 respectivamente. Ambas comunidades comparten 53 especies y presentan una semejanza florística del 49 %; mostraron diferencias significativas en la densidad y cobertura de especies. Este estudio contribuye al entendimiento de la estructura y el recambio de especies en la flora de comunidades de zonas secas de México.
Fitosociología de malezas en plantaciones bananeras en el departamento del Magdalena, Colombia
Authors: Quintero Pertúz Irma , Carbonó Delahoz Eduino César , Hoyos Castaño Verónica , Jarma-Orozco Alfredo De Jesus , Plaza Guido
Published: April 2021

Las malezas constituyen un factor limitante en la producción de banano en Colombia. Para contribuir a la fundamentación de su manejo, se propuso evaluar la estructura y diversidad de las comunidades de malezas en cuatro zonas productoras de banano (Alta, Media, Baja y Norte) en el departamento del Magdalena. Se realizaron levantamientos durante 2016 y 2017 mediante muestreo sistemático utilizando cuadrados de 1m2 en fincas seleccionadas en cada zona con método de control químico, cobertura y mecánico, y se calculó la frecuencia, densidad y dominancia de las malezas para estimar el índice de valor de importancia (IVI), la diversidad alfa y el índice de similitud de Bray-Curtis. Se identificaron 122 especies incluidas en 93 géneros y 39 familias. Poaceae y Cyperaceae presentaron mayor riqueza específica y Commelinaceae mayor IVI. Commelina erecta, Axonopus compressus y Melothria pendula fueron las especies de mayor importancia ecológica en las plantaciones. Los parámetros fitosociológicos difieren entre zonas y métodos de control. Las zonas con mayor y menor diversidad fueron Norte y Baja, respectivamente. Hubo mayor similitud entre las zonas Media y Baja, así como entre Media y Alta, en tanto, la Norte fue la más disímil. Pocas especies fueron muy abundantes y frecuentes, señalando la tendencia a baja diversidad. Los resultados más importantes permiten concluir que las condiciones agroecológicas de cada zona y el método de control empleado influyen en los parámetros fitosociológicos y diversidad de especies, determinando la composición y estructura de las comunidades de malezas asociadas al cultivo en el departamento del Magdalena.
Diversity and use of trees and shrubs in smallholder farming systems in the Colombian Andes
Authors: García Néstor , Peñaranda Juanita , Sarmiento Natalia
Published: April 2021

This article describes the diversity and use of trees and shrubs in smallholder farming systems in three municipalities of the department of Boyacá in the Colombian Andes, and tests the relations between species richness, use, and a set of socio-economic and structural variables. We conducted ethnobotanical walks and semi-structured interviews on 24 farms to characterize all tree and shrub species. In total, we recorded 142 species with a predominance of natives (88) versus exotics (54). Species richness ranged between four and 40 (X = 25.17; SD = 10.13) per farm and was homogeneous among the municipalities (P > 0.05, Kruskal-Wallis test). We recorded 52 wild species, eight of them endemic, all representative of the surrounding native flora, of which 23 % had some type of use. Cultivated species were mostly represented by exotics that had been planted primarily as live fences, ornamentals, or edibles. Species richness was positively correlated with the size of the farms (rs = 0.664, P<0.001) and negatively with their proximity to areas with natural vegetation (rs = -0.515, P = 0.010). Smallholder agriculture favors the establishment of trees and shrubs; we, therefore, stress the important role of these productive systems for the conservation of biodiversity in the Colombian Andes.
Ensamblajes de anuros y heterogeneidad espacial en un ecosistema de páramo de Colombia
Authors: Duarte-Ballesteros Laura , Urbina-Cardona J. Nicolás , Saboyá-Acosta Liliana Patricia
Published: April 2021

El presente estudio buscó determinar el efecto de la heterogeneidad espacial, producto de los mosaicos vegetales y gradientes ambientales y estructurales del páramo, sobre la estructura del ensamblaje de anuros en un sector del Parque Nacional Chingaza. Se registraron variables ambientales y estructurales en seis mosaicos de vegetación y se calcularon métricas de paisaje en áreas de influencia de 50 y 100 m, a partir de fotografías aéreas tomadas con dron. Al concluir 162 horas/persona de muestreo, se encontraron 45 individuos pertenecientes a cuatro especies. Las variables mayormente relacionadas con la estructura de los ensamblajes de anuros, variaron con el área de influencia, así: (a) a nivel del gradiente ambiental-estructural en los mosaicos de vegetación (escala de microhábitat), el porcentaje de frailejones, número de troncos de frailejones caídos, temperatura del aire y velocidad del viento fueron las más determinantes; (b) a nivel de la unidad de paisaje, el área de influencia de 50 m, se evidenció el efecto del número de clases y en particular la extensión de las clases de turbera y vegetación de turbera. Finalmente, (c) al área de influencia de 100 m, la configuración de las unidades de paisaje fue más importante, principalmente la extensión de las clases de turbera y matorrales bajos entremezclados con pajonales y frailejonales. Los resultados sugieren que los anuros presentan una respuesta dependiente de la escala ante la heterogeneidad espacial, aspecto que se debe considerar en los planes de manejo del área protegida al momento de estructurar esquemas de monitoreo poblacional.