bluuebunny/crossref_metadata_2025 huggingface dataset:
Technology Start-up Marketing Strategy and Lifecycle: First Empirical Findings by Qualitative Research
Authors: Ulč Jakub , Mandel Miroslav
Published: February 2022

Purpose of the article: Technology start-ups go through certain stages in their lifecycle. In each stage of the lifecycle, there is a different approach to marketing strategy and its application through marketing activities. Creating an empirically based framework of a technology start up marketing strategy based on each lifecycle stage will increase the chances of success for such a technology start-up.Methodology: This research is based on qualitative research using structured interviews with the Czech and Slovak technology start-ups. The questions were validated by pilot research with a selected technology start-up and modified accordingly. The sample was obtained using non probability sampling methods. Deductive coding and content analysis are used. The outputs are represented by categorisation and followed by summarisation in the empirically based framework.Scientific aim: The aim is to create an empirically based framework of the marketing strategy of a technology start-up based on the lifecycle stages. The empirically based framework will be developed as an initial effort to gain knowledge in this area and to develop questions or the research direction for the future.Findings: The empirically based framework is developed through qualitative research to define the core marketing activities at a specific lifecycle stage. These activities are divided into categories of coding. The technology start-up should immediately and proactively develop marketing activities at the beginning of its foundation, not only internally but also with external support.Conclusions: For boosting the success of a technology start-up, it is necessary to create customised marketing activities. The ambiguous definition of a start-up hinders the advancement of the body of knowledge in this area and therefore primary research methods must be developed. The research is limited by the broad scope of the given topic. The marketing strategy area as such cannot be entirely covered and therefore sub-points need to be further addressed.
Elimination of stripe artifacts in light sheet fluorescence microscopy using an attention-based residual neural network
Authors: Wei Zechen , Wu Xiangjun , Tong Wei , Zhang Suhui , Yang Xin , Tian Jie , Hui Hui
Published: February 2022

Stripe artifacts can deteriorate the quality of light sheet fluorescence microscopy (LSFM) images. Owing to the inhomogeneous, high-absorption, or scattering objects located in the excitation light path, stripe artifacts are generated in LSFM images in various directions and types, such as horizontal, anisotropic, or multidirectional anisotropic. These artifacts severely degrade the quality of LSFM images. To address this issue, we proposed a new deep-learning-based approach for the elimination of stripe artifacts. This method utilizes an encoder–decoder structure of UNet integrated with residual blocks and attention modules between successive convolutional layers. Our attention module was implemented in the residual blocks to learn useful features and suppress the residual features. The proposed network was trained and validated by generating three different degradation datasets with different types of stripe artifacts in LSFM images. Our method can effectively remove different stripes in generated and actual LSFM images distorted by stripe artifacts. Besides, quantitative analysis and extensive comparison results demonstrated that our method performs the best compared with classical image-based processing algorithms and other powerful deep-learning-based destriping methods for all three generated datasets. Thus, our method has tremendous application prospects to LSFM, and its use can be easily extended to images reconstructed by other modalities affected by the presence of stripe artifacts.
Color constancy with an optimized regularized random vector functional link based on an improved equilibrium optimizer
Authors: Zhou Zhiyu , Yang Xingfan , Zhu Zefei , Wang Yaming , Liu Dexin
Published: February 2022

In order to improve the accuracy of illumination estimation, this paper proposes a color constancy algorithm based on an improved equilibrium optimizer (IEO) to optimize the network structure parameters and common parameters of the regularized random vector functional link (RRVFL) at the same time. First, the initial search agent (population) of the equilibrium optimizer algorithm is generated through opposition-based learning, and the particles (individuals in the population) of the search agent are updated using the IEO algorithm. Compared with the completely randomly generated search agent, the method of initializing the search agent through the IEO algorithm has a better convergence effect. Then, each segment of the search agent is mapped to the corresponding parameters of the RRVFL, and the effective input weight and hidden layer bias are selected according to the node activation to generate the network structure, which can realize the simultaneous optimization of hyperparameters and common parameters. Finally, by calculating the output weight, the light source color prediction of the image under unknown illumination is performed, and the image is corrected. Comparison experiments show that the IEO-RRVFL color constancy algorithm proposed in this paper has higher accuracy and better stability than other comparison algorithms.
Experimental demonstration of all-optical aggregation and de-aggregation for a QPSK signal in an elastic optical network
Authors: Ding Yu , Wang Hongxiang , Yuefeng Ji
Published: February 2022

The aggregation and de-aggregation between one QPSK and two BPSK signals are experimentally demonstrated based on cross-phase modulation (XPM) effects and phase-sensitive amplification (PSA), aiming to improve flexible spectral efficiency in the elastic optical network. Benefiting from the nonlinear-optical loop mirror (NOLM), the two BPSK signals can be extracted without any information redundancy for the de-aggregation scheme. The wavelength of the extracted signals stay the same as the input signal in the NOLM. Moreover, the aggregation from two BPSK signals to one QPSK signal is also successfully achieved. The feasibility of the two schemes can be confirmed by the transfer functions and the input-output constellation. The bit-error-rate (BER) and error vector magnitude(EVM) performance of the two schemes are also investigated and the corresponding OSNRs for error-free signal recovery are obtained respectively. The proposed schemes contribute to the realization of flexible optical networks and can be applied in the future gateway node between optical sub-networks.
High-precision micro-displacement measurement method based on alternately oscillating optoelectronic oscillators
Authors: Wang Ju , Guo Xuexin , Yu Jinlong , Ma Chuang , Yu Yang , Luo Hao , Liu Lingchao
Published: February 2022

We propose a high-precision micro-displacement measurement method based on alternately oscillating optoelectronic oscillators (OEOs). This method uses a reference loop to compensate for the change in the measuring loop length except for the displacement to be measured. Therefore, self-calibration is realized without using a phase-locked loop to control the loop length, greatly simplifying the system. The measurement range is 20 mm, and the measurement precision is <300 nm, which is limited by the incomplete consistency between the reference and the measuring loops, with the exception of the displacement to be measured and environmental disturbances resulting from the spatial optical path.
Demonstration of wavelength-swept laser using cholesteric liquid-crystal cavity and its application for laser scanning
Authors: Inoue Yo , Moritake Hiroshi
Published: February 2022

A cholesteric liquid-crystal gel (ChLCG) is fabricated by photopolymerizing a ChLC doped with a mesogenic monomer at a high concentration of 38.2 wt%. The reflection band of the ChLCG exhibits a fast, continuous, and time-varying wavelength shift of the order of kilohertz by applying a sine wave voltage. Swept lasing at a swept rate of 100 Hz and with a swept range of 12 nm can be achieved by irradiating a dye-doped ChLCG with a quasi-continuous-wave laser. When the swept laser light is introduced to a diffracting grating, a laser scanning device is demonstrated.
Dual-purpose optical fiber sensor: relative humidity and ammonia detection
Authors: Ansari Mohamad , Moravvej-Farshi Mohammad Kazem
Published: February 2022

We propose a dual−purpose sensor to detect ammonia besides relative humidity with tapered multimode fiber (TMMF) as the sensor structure and silica gel as the sensing layer. In achieving the desired TMMF, we heated and pulled a few pieces of multimode fibers to obtain 9-mm long tapered regions with different diameters in the range of 4−40 µm. Then synthesized silica gel by sol-gel method and passed the tapered section of the TMMFs through drops of silica gel to form the sensing layers. Using the wavelength shift and output power reduction appearing in the fiber transmission spectrum, we determine the sensor response to the alteration of ammonia concentration and relative humidity in the environment. Our experimental results reveal that a decrease in the tapered waist gives rise to an increase in the sensor sensitivity. The same results show that the highest measured sensitivity is 14.8 pm/ppm (for ammonia) and 0.435 dB/%RH (for relative humidity) when we coat the tapered region of a TMMF of 4−µm waist diameter with silica gel. Moreover, the time responses for relative humidity and ammonia sensors are 10 and 32 s, and their corresponding recovery times are 8 and 19.5 s.
Efficiency of pulse pumped soliton microcombs
Authors: Li Jiang , Bao Chengying , Ji Qing-Xin , Wang Heming , Wu Lue , Leifer Stephanie , Beichman Charles , Vahala Kerry
Published: February 2022

Temporal soliton mode locking in coherently pumped microcavities is a promising route towards miniaturized frequency comb systems. However, the power efficiency of the resulting microcombs is usually quite low. Soliton generation by pulse pumping provides a way to increase conversion efficiency (so far, as high as 8%). Here, we study conversion efficiency and report a single-soliton conversion efficiency as high as 54% using a scanning laser, as well as a steady-state single-soliton conversion efficiency as high as 34%. We use the Lagrangian approach to develop analytical expressions for efficiency and soliton temporal placement within the pumping pulse, and our measurements reveal features in the tuning dependence of soliton power and efficiency not seen in continuous pumping. Our experimentally confirmed expressions for efficiency will be useful in understanding advantages and limitations of pulse pumped systems.
Future loss of local-scale thermal refugia in coral reef ecosystems
Authors: Dixon Adele M. , Forster Piers M. , Heron Scott F. , Stoner Anne M. K. , Beger Maria
Published: February 2022

Thermal refugia underpin climate-smart management of coral reefs, but whether current thermal refugia will remain so under future warming is uncertain. We use statistical downscaling to provide the highest resolution thermal stress projections (0.01°/1 km, >230,000 reef pixels) currently available for coral reefs and identify future refugia on locally manageable scales. Here, we show that climate change will overwhelm current local-scale refugia, with declines in global thermal refugia from 84% of global coral reef pixels in the present-day climate to 0.2% at 1.5°C, and 0% at 2.0°C of global warming. Local-scale oceanographic features such as upwelling and strong ocean currents only rarely provide future thermal refugia. We confirm that warming of 1.5°C relative to pre-industrial levels will be catastrophic for coral reefs. Focusing management efforts on thermal refugia may only be effective in the short-term. Promoting adaptation to higher temperatures and facilitating migration will instead be needed to secure coral reef survival.
Rapid global phaseout of animal agriculture has the potential to stabilize greenhouse gas levels for 30 years and offset 68 percent of CO2 emissions this century
Authors: Eisen Michael B. , Brown Patrick O.
Published: February 2022

Animal agriculture contributes significantly to global warming through ongoing emissions of the potent greenhouse gases methane and nitrous oxide, and displacement of biomass carbon on the land used to support livestock. However, because estimates of the magnitude of the effect of ending animal agriculture often focus on only one factor, the full potential benefit of a more radical change remains underappreciated. Here we quantify the full “climate opportunity cost” of current global livestock production, by modeling the combined, long-term effects of emission reductions and biomass recovery that would be unlocked by a phaseout of animal agriculture. We show that, even in the absence of any other emission reductions, persistent drops in atmospheric methane and nitrous oxide levels, and slower carbon dioxide accumulation, following a phaseout of livestock production would, through the end of the century, have the same cumulative effect on the warming potential of the atmosphere as a 25 gigaton per year reduction in anthropogenic CO2emissions, providing half of the net emission reductions necessary to limit warming to 2°C. The magnitude and rapidity of these potential effects should place the reduction or elimination of animal agriculture at the forefront of strategies for averting disastrous climate change.
Essential medicines wastage assessment in the Solomon Islands
Authors: Dadari Ibrahim , Usuf Effua
Published: February 2022

The World Health Organization (WHO) regularly updates its list of Essential medicines. However, the use of these medicines in the Solomon Islands is less well described. We assessed supplies, prescriptions, and stocks of zinc, oral rehydration salt (ORS), vitamin A, and albendazole in six provinces of the Solomon Islands for 2017 and 2018. We also conducted a stocktake of available medicine supplies at the point of data collection. We found that quantities of drugs supplied were in excess of the prescriptions and stock records at the facilities were inadequate. There were expired drugs at the facilities. Out of the 20 health facilities with available data, 11 (55%), 3 (15%), and 1 (5%) had expired stock of ORS, albendazole and vitamin A respectively. No expired zinc tablets were recorded. A revision of the medicines stock management system is necessary to adequately quantify essential medicine wastage and improve the stock management in the Solomon Islands.
The status of prehospital care delivery for COVID-19 patients in Addis Ababa, Ethiopia: The study emphasizing adverse events occurring in prehospital transport and associated factors
Authors: Baru Ararso , Sultan Menbeu , Beza Lemlem
Published: February 2022

Background

COVID-19 patients may require emergency medical services for emergent treatment and/or transport to a hospital for further treatment. However, it is common for the patients to experience adverse events during transport, even the shortest transport may cause life-threatening conditions. Most of the studies that have been done on prehospital care of COVID-19 patients were conducted in developed countries. Differences in population demographics and economy may limit the generalizability of available studies. So, this study was aimed at investigating the status of prehospital care delivery for COVID-19 patients in Addis Ababa focusing on adverse events that occurred during transport and associated factors.

Methods

A total of 233 patients consecutively transported to Saint Paul’s Hospital Millennium Medical College from November 6 to December 31, 2020, were included in the study. A team of physicians and nurses collected the data using a structured questionnaire. Descriptive statistics were used to summarize data, and ordinal logistic regression was carried out to assess the association between explanatory variables and the outcome variable. Results are presented using frequency, percentage, chi-square, crude and adjusted odds ratios (OR) with 95% confidence intervals.

Results

The overall level of adverse events in prehospital setting was 44.2%. Having history of at least one chronic medical illness, [AOR3.2 (95%; CI; 1.11–9.53)]; distance traveled to reach destination facility, [AOR 0.11(95%; CI; 0.02–0.54)]; failure to recognize and administer oxygen to the patient in need of oxygen, [AOR 15.0(95%; CI; 4.0–55.7)]; absent or malfunctioned suctioning device, [AOR 4.0(95%; CI; 1.2–13.0)]; patients handling mishaps, [AOR 12.7(95%; CI; 2.9–56.8)] were the factors associated with adverse events in prehospital transport of COVID-19 patients.

Conclusions

There were a significant proportion of adverse events in prehospital care among COVID-19 patients. Most of the adverse events were preventable. There is an urgent need to strengthen prehospital emergency care in Ethiopia by equipping the ambulances with essential and properly functioning equipment and trained manpower. Awareness creation and training of transport staff in identifying potential hazards, at-risk patients, adequate documentation, and patient handling during transport could help to prevent or minimize adverse events in prehospital care.
Characterization of intracellular calcium mobilization induced by remimazolam, a newly approved intravenous anesthetic
Authors: Urabe Tomoaki , Miyoshi Hirotsugu , Narasaki Soshi , Yanase Yuhki , Uchida Kazue , Noguchi Soma , Hide Michihiro , Tsutsumi Yasuo M. , Sakai Norio
Published: February 2022

Many anesthetics, including Propofol, have been reported to induce elevation of intracellular calcium, and we were interested to investigate the possible contribution of calcium elevation to the mechanism of the newly approved remimazolam actions. Remimazolam is an intravenous anesthetic first approved in Japan in July 2020, and is thought to exert its anesthetic actions via γ-aminobutyric acid A (GABAA) receptors; however, the precise mechanisms of how remimazolam elevates intracellular calcium levels remains unclear. We examined the remimazolam-induced elevation of intracellular calcium using SHSY-5Y neuroblastoma cells, COS-7 cells, HEK293 cells, HeLa cells, and human umbilical vein endothelial cells (HUVECs) loaded with fluorescent dyes for live imaging. We confirmed that high concentrations of remimazolam (greater than 300 μM) elevated intracellular calcium in a dose-dependent manner in these cells tested. This phenomenon was not influenced by elimination of extracellular calcium. The calcium elevation was abolished when intracellular or intraendoplasmic reticulum (ER) calcium was depleted by BAPTA-AM or thapsigargin, respectively, suggesting that calcium was mobilized from the ER. Inhibitors of G-protein coupled receptors (GPCRs)-mediated signals, including U-73122, a phospholipase C (PLC) inhibitor and xestospongin C, an inositol 1,4,5-triphosphate receptors (IP3R) antagonist, significantly suppressed remimazolam-induced calcium elevation, whereas dantrolene, a ryanodine receptor antagonist, did not influence remimazolam-induced calcium elevation. Meanwhile, live imaging of ER during remimazolam stimulation using ER-tracker showed no morphological changes. These results suggest that high doses of remimazolam increased intracellular calcium concentration in a dose-dependent manner in each cell tested, which was predicted to be caused by calcium mobilization from the ER. In addition, our studies using various inhibitors revealed that this calcium elevation might be mediated by the GPCRs-IP3 pathway. However, further studies are required to identify which type of GPCRs is involved.
Symmachus: Levelek Praetextatushoz
Authors: Tóth Orsolya
Published: February 2022

A 4. századi római arisztokrácia világába engednek bepillantást Symmachus azon levelei, amelyeket Vettius Agorius Praetextatushoz írt. A nagy tiszteletnek örvendő senator, a régi római vallás egyik legnagyobb védelmezője Symmachus mentora és kedves barátja volt. A hozzá szóló levelek, amelyek képet adnak a korszak előkelőinek elfoglaltságairól, életmódjáról és mentalitásáról, először jelennek meg jegyzetekkel kísért magyar fordításban.
Megjegyzések Sapphó Kypris-költeményének rekonstrukciójához és értelmezéséhez (5–6skk.)
Authors: Mayer Péter
Published: February 2022

A tanulmány számba veszi a Sapphó Kypris-költeménye 5–6. sorára vonatkozó lehetséges rekonstrukciókat, és kritikailag elemzi, valamint értelmezi ezeket a sapphói életmű és a korai görög líra tágabb összefüggésében.
Bases para el diálogo entre la filosofía del límite y la filosofía de la nada
Authors: Segade Alonso Carlos E.
Published: February 2022

La filosofía de la nada fue la respuesta ofrecida por Kitaro Nishida a la necesidad de asentar las bases de un diálogo filosófico con Occidente. Se propone en este trabajo que ese diálogo que todavía prosigue en la Escuela de Kyoto tenga entre uno de sus referentes occidentales a la filosofía del límite de Eugenio Trías. Para ello, y tras un repaso de los conceptos principales de cada propuesta filosófica, se considerará la adecuación del método categorial de análisis histórico propuesto por Trías y se estudiarán los conceptos fundantes de «nada» y «límite», que a su vez son la base para una ética humanista capaz de entablar un diálogo entre las dos culturas.
Belleza y moral en Yuriko Saito
Authors: Godoy Domínguez M.ª Jesús
Published: February 2022

Este trabajo pretende abordar los juicios estético-morales establecidos por Yuriko Saito en el ámbito reciente de la estética de lo cotidiano, a la luz de la belleza funcionalista del pensador ilustrado David Hume. Para ello, se desentraña el mecanismo afectivo sobre el que descansa la experiencia estética tanto en el caso del objeto intrascendente de todos los días sobre el que teoriza Saito, como en el caso del objeto utilitario sobre el que discurre Hume y que demuestra que el juicio de gusto es uno solo, en ambos pensadores, con el juicio moral. Se concluye así que la simpatía por obra de la cual existe la belleza en el joven Hume, al acabar virando hacia una empatía prematura en el Hume maduro, refuerza el entronque con Saito, con su preocupación por el otro y su deseo de alcanzar un mundo mejor.
The Interactive Learning Model: A theory that assists the L2 learner in achieving self-awareness
Authors: Johnston Christine A. , Klein Gabriella B. , Johnston Noah , Johnston Joel
Published: February 2022

This study uses the Interactive Learning Model theory to explore the nature of self-awareness within each of three L2 learners. Using the Learning Connections Inventory (LCI), a validated and reliable learning instrument, each participant identified their combination of learning patterns. The subjects then recalled specific L2 learning experiences, relating them in first person narratives. Next, each subject composed anecdotes and reflections based on their narratives. They also participated in one-on-one interviews in which they described their learning experiences during basic L2 learning activities: vocabulary, grammar, writing, conversation, and passive listening during movies, live theatre, spectator sports, and television. Our analysis of the LCI outcomes and selfreported learning experiences demonstrated that the self-awareness gained from understanding their combination of learning patterns and expanded by the self-reflection activities, increased the participants’ ability to articulate the nature of their self-awareness and to identify evidence of their growth in self-awareness during L2 learning.
Antibodies targeting enzyme inhibition as potential tools for research and drug development
Authors: Pérez de la Lastra José Manuel , Baca-González Victoria , González-Acosta Sergio , Asensio-Calavia Patricia , Otazo-Pérez Andrea , Morales-delaNuez Antonio
Published: February 2022

Antibodies have transformed biomedical research and are now being used for different experimental applications. Generally, the interaction of enzymes with their specific antibodies can lead to a reduction in their enzymatic activity. The effect of the antibody is dependent on its narrow i.e. the regions of the enzyme to which it is directed. The mechanism of this inhibition is rarely a direct combination of the antibodies with the catalytic site, but is rather due to steric hindrance, barring the substrate access to the active site. In several systems, however, the interaction with the antibody induces conformational changes on the enzyme that can either inhibit or enhance its catalytic activity. The extent of enzyme inhibition or enhancement is, therefore, a reflection of the nature and distribution of the various antigenic determinants on the enzyme molecule. Currently, the mode of action of many enzymes has been elucidated at the molecular level. We here review the molecular mechanisms and recent trends by which antibodies inhibit the catalytic activity of enzymes and provide examples of how specific antibodies can be useful for the neutralization of biologically active molecules
COVID-19 lockdown impact on CERN seismic station ambient noise levels
Authors: Ścisło Łukasz , Łacny Łukasz , Guinchard Michael
Published: February 2022

Seismic measuring stations do not only record seismic waves. They also pick up tremors caused by other factors: these are known as seismic background noise. In normal conditions, this environmental background is steady over a long time. This article presents the influence of high reduction of human activity due to COVID-19 initial lockdown on ground vibration in the Large Hadron Collider tunnel at the European Organization for Nuclear Research.
On the effects of e-participation on shadow economy: a worldwide empirical analysis
Authors: Sacchi Agnese , Santolini Raffaella , Schneider Friedrich
Published: February 2022

This paper explores the relationship between the e-participation attitude of citizens and the size of the shadow economy, whose consequences could be detrimental to countries’ economic development. We exploit a rich panel dataset for 149 countries characterized by a large digital divide within their public sectors, different levels of both income and democratic institutions at work over years 2003–2015. Using the instrumental variables approach to address potential endogeneity issues, we find that e-participation significantly contributes to reducing the shadow economy. Due to its interactive nature for both businesses and citizens, it positively affects the individuals’ behavior against informal economic activities by creating a more collaborative environment between the government and its stakeholders.
Regioselectivity in the reaction of 5-amino-3-anilino-1H-pyrazole-4-carbonitrile with cinnamonitriles and enaminones: Synthesis of functionally substituted pyrazolo[1,5-a]pyrimidine derivatives
Authors: Moustafa Moustafa Sherif , Nour-Eldeen Ahmed Moukhtar , Al-Mousawi Saleh Mohamed , El-Hameed Afaf Abd , Magdy Michael , Sadek Kamal Usef
Published: February 2022

The development of efficient methods for the synthesis of polyfunctional N-heterocycles is an important area of research in organic and medicinal chemistry. Pyrazolo[1,5-a]pyrimidine derivatives are purine analogous of biomedical importance and have been extremely studied for their broad spectrum of biological activities. Recently, they have attracted great interest in materials science owing to their photophysical properties. 3(5)-Aminopyrazoles are extensively utilized in the synthesis of condensed heterocyclic systems, particularly pyrazolo[1,5-a]pyrimidines via the reaction with 1,3-biselectrophilic reagents. However, the information available in the literature provides little in the way of reasoning their cyclization, particularly the initial attack either by the exocyclic amino group or endocyclic nitrogen. Unfortunately, the relative nucleophilicity of exo- and endocyclic nitrogen atoms in 1-unsubstituted 3(5)-aminopyrazoles is not clear and contradicting. It has been found that other factors can modulate the regioselectivity rather than basicity or steric hindrance for both active sites. The reported studies in the structure–activity relationship revealed that pyrazolo[1,5-a]pyrimidines having a substitution at fifth, sixth, and seventh positions possess potent biological activities, especially those with an amino group at the seventh position. We here developed a regioselective, high yield synthesis of 7-amino-5-arylpyrazolo[1,5-a]pyrimidine-3,6-dicarbonitriles by the reaction of N-(5-amino-4-cyano-1H-pyrazole-3-yl)-benzamide with various cinnamonitriles and enaminones in pyridine at 120°C under controlled microwave heating conditions. All structures of newly synthesized compounds were established by analytical and spectral data as well as single-crystal diffraction and rationalized for their formation.
Structural and morphological investigations of barium zirconium titanate particles synthesized by the Pechini method
Authors: Sözen Aktaş Pelin
Published: February 2022

Barium zirconium titanate systems are lead-free, environmentally friendly materials exhibiting relaxor behavior with increasing Zr content. Therefore, the study proposed preparing and characterization of an ecologically favorable Pb-free relaxor from Ba(Zr0.5Ti0.5)O3 (BZT). The results reported here are based on the research of BZT micrometric powders prepared by the Pechini method. The phase evolution was monitored by X-ray diffraction from 800 °C to 1300 °C, and results show that the formation of BZT starts around 1050 °C and continues until 1300 °C. The Rietveld refinement of data at 1300 °C confirms that BZT has a cubic structure. The thermal and structural properties of BZT samples were identified by thermogravimetric analysis and Fourier-transform infrared spectroscopy. Scanning electron microscopy results reveal that the synthesized particles are micron-sized (2–2.8 µm), rounded, polygonal-shaped, and agglomerated.
Low temperature synthesis of SnSr(OH)6nanoflowers and photocatalytic performance for organic pollutants
Authors: Xue Zeyang , Li Feiyang , Yu Chunhu , Huang Jianfeng , Tao Feihu , Cai Zhengyu , Zhang Hui , Pei Lizhai
Published: February 2022

A simple low temperature hydrothermal route has been used for the synthesis of strontium tin hydroxide (SrSn(OH)6) nanoflowers. The synthesized SrSn(OH)6nanoflowers were investigated by means of powder X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy and solid ultraviolet−visible diffuse reflectance spectroscopy. The SrSn(OH)6nanoflowers are composed of nanorods with hexagonal structure, length and diameter of about 2 µm and 30–100 nm, respectively. The growth process of the SrSn(OH)6nanoflowers is proposed as the Ostwald ripening and crystal splitting process based on the morphological evolution from different hydrothermal conditions. The band gap of the nanoflowers is 3.53 eV. The SrSn(OH)6nanoflowers were utilized for the photocatalytic degradation of gentian violet under ultraviolet light irradiation. The roles of various factors including irradiation time and nanoflower dosage on the photocatalytic activity of the SrSn(OH)6nanoflowers are discussed. The possible photocatalytic mechanism for gentian violet degradation using the SrSn(OH)6nanoflowers was determined by radical trapping experiments. The SrSn(OH)6nanoflowers possess good stability and are an efficient photocatalyst for the removal of organic pollutants.
Changes in spatial frames of reference use in Iwaidja in different intergenerational contexts
Authors: Edmonds-Wathen Cris
Published: February 2022

Research into sociocultural factors affecting the use of spatial frames of reference (FoR) has begun to move away from characterizing FoR choice as inherent to each language, instead emphasizing variation within speech communities, but has so far paid little attention to variation in individual speaker’s FoR use with different addressees. This paper reports on differences in two senior adults’ use of FoRs in Iwaidja when addressing a peer compared to addressing a child. Performing the Man and Tree task, the speakers made frequent use of geocentric descriptions with their peers, and substantially fewer geocentric descriptions with a child. The study was conducted in a complex multilingual speech environment where younger generations’ language use is shifting away from Iwaidja towards English and to other Australian languages. Factors motivating the different FoR choices in child-directed speech may include elements of parentese and accommodation to the children’s incomplete acquisition of Iwaidja. The children’s contact with English, particularly through schooling, may affect the adults’ expectations of the children’s acquisition of frames of reference in English. Drawing attention to the impact of the addressee in spatial speech, this study adds to understanding sociocultural elements of spatial reference in the context of language contact and shift.
The influence of language, culture, and environment on the use of spatial referencing in a multilingual context: Taiwan as a test case
Authors: Lin Yen-Ting
Published: February 2022

This study examines the Sociotopographic Model (Palmer, Bill, Jonathon Lum, Jonathan Schlossberg & Alice Gaby. 2017. How does the environment shape spatial language? Evidence for sociotopography.Linguistic Typology21(3). 457–491. DOI:10.1515/lingty-2017-0011) by exploring the use of spatial frames of reference in two genealogically related languages with rather distinct spatial features in a multilingual context. Taiwanese Min Nan (TMN) and Taiwanese Mandarin Chinese (MC), exhibit distinct features in spatial reference in small-scale space, including a geocentric preference among TMN speakers for using cardinal directions or external landmarks and a relative preference among MC speakers for projecting the viewer’s perspective onto the object. The study extended the research design of Bohnemeyer and his colleagues (Bohnemeyer, Jürgen, Katharine T. Donelson, Randi Tucker, Elena Benedicto, Alejandra Capistrán Garza, Alyson Eggleston, Néstor Hernández Green, María Hernández Gómez, Samuel Herrera Castro, Carolyn K. O’Meara, Enrique Palancar, Gabriela Pérez Báez, Gilles Polian & Rodrigo Romero Méndez. 2014. The cultural transmission of spatial cognition: Evidence from a large-scale study. In Paul Bello, Marcello Guarini, Marjorie McShane & Brian Scassellati (eds.),Proceedings of the 36th Annual Conference of the Cognitive Science Society, 212–217. Austin, TX: Cognitive Science Society) to the scope of bilingualism in order to explore how language, culture, and environment affect the use of spatial reference in bilinguals as compared to monolinguals. The research method comprised a discourse and a recall memory study. Contrary to the alignment between discourse and recall memory found in monolinguals, bilinguals displayed mixed patterns. Regression analyses indicated that, in addition to language, effects of environment emerged: topography was positively correlated with geocentric use, supporting the Topographic Correspondence Hypothesis (Palmer, Bill, Alice Gaby, Jonathon Lum & Jonathan Schlossberg. 2016. Topography and frame of reference in the threatened ecological niche of the atoll.Paper presented at “Geographic grounding: Place, direction and landscape in the grammars of the world”, University of Copenhagen, May 2016). A strong education effect had an impact on geocentric use in both studies, suggesting the possibility of the cultural mediation between language and environment.
Enhanced mechanical and gas barrier performance of plasticized cellulose nanofibril films
Authors: Aulin Christian , Flodberg Göran , Ström Göran , Lindström Tom
Published: February 2022

Cellulose nanofibrils (CNF) are mixed with plasticizers; sorbitol and glycerol, through high-pressure homogenization to prepare multifunctional biohybrid films. The resulting plasticized films obtained after solvent evaporation are strong, flexible and demonstrate superior toughness and optical transparency. The oxygen barrier properties of the biohybrid films outperform commercial packaging materials. The sorbitol-plasticized CNF films possess excellent oxygen barrier properties, 0.34 cm3·μm/m2·day·kPa at 50 % relative humidity, while significantly enhancing the toughness and fracture strength of the films. CNF films plasticized by 20 wt.% of sorbitol and glycerol could before rupture, be strained to about 9 % and 12 %, respectively. The toughness of the plasticized films increased by ca. 300 % compared to the pristine CNF film. Furthermore, the water vapor barrier properties of the biohybrid films were also preserved by the addition of sorbitol. CNF films plasticized with sorbitol was demonstrated to simultaneously enhance fracture toughness, work of fracture, softening behavior while preserving gas barrier properties. Highly favorable thermomechanical characteristics were found with CNF/sorbitol combinations and motivate further work on this material system, for instance as a thermoformable matrix in biocomposite materials. The unique combination of excellent oxygen barrier behavior, formability and optical transparency suggest the potential of these CNF-based films as an alternative in flexible packaging of oxygen sensitive devices like thin-film transistors or organic light-emitting diode displays, gas storage applications and as barrier coatings/laminations in packaging applications, including free-standing films as aluminium-replacement in liquid board and primary packaging, as replacement for polyethylene (PE) in wrapping paper, e. g. sweats and confectionary.
A hard-core soft-shell model for vibration condition of fresh concrete based on low water-cement ratio concrete
Authors: Li Xiaotian , Xie Guangnian , Gao Zhurui , Wang Chuxin
Published: February 2022

The newly developed vibration-compacting modular production technology of concrete with low water-cement ratio puts forward new requirements for the study of rheological mechanical model of concrete. The existing contact model of discrete element method cannot effectively express the complex dynamic relationship between concrete aggregate and mortar under vibration. In this article, an improved hard-core soft-shell contact model, which is suitable for the simulation of concrete with low water-cement ratio under vibration state, is proposed according to the vibration and compactness characteristics of the concrete. According to the rheological properties of the concrete mortar, the calculation method of soft-shell force is improved. The relationship between the shear stress and its displacement in the process of trying to solve the tangential soft-shell is clarified. In order to characterize the adsorption effect of mortar on aggregate, the gravitation is added in the normal soft-shell force calculation. Slump test under non-vibration state and L-box test under vibration state are carried out to verify the correctness of the improved hard-core soft-shell contact model. The improved hard-core soft-shell contact model can effectively simulate the dynamic response of the complex multiphase concrete fluids with low water-cement ratio, and accurately characterize the change in its rheological properties.
Laser-Doppler-Anemometrie-Messungen in einem quadratischen Kanal mit eng beieinanderliegenden Rippen an einer Wand
Authors: Ruck Sebastian , Arbeiter Frederik , Petri Torben
Published: February 2022

In der vorliegenden Arbeit werden Ergebnisse von Laser-Doppler-Anemometrie (LDA)-Geschwindigkeitsmessungen in einem einseitig mit transversal orientierten Rippen-Rauheiten strukturierten quadratischen Kanal für die Strömung mit einer Reynolds-Zahl von

Re

H

=
5
,
0
·

10

4

{\mathit{Re}_{H}}=5,0\cdot {10^{4}}

vorgestellt. Das Rippenabstand-Rippenhöhe-Verhältnis war 3 und die Verblockungsrate betrug

6
,
7

%

6,7\hspace{0.1667em}\%

. Es werden Verteilungen der mittleren Geschwindigkeiten, Reynolds-Spannungen sowie Triple-Geschwindigkeit-Korrelationen präsentiert. Die Ergebnisse zeigen die Entwicklung einer dreidimensionalen Sekundärströmung oberhalb der Rippen, wodurch sich ein schwach advektiver wandnormaler Fluidtransport zwischen der rippennahen Strömung und der Kanalkernströmung einstellt. Der Einfluss der Rippen-Rauheiten auf das turbulente Strömungsgeschehen und die einhergehenden turbulenten Austauschvorgänge ist jedoch auf die unmittelbare Rippennähe begrenzt. Die anhand der statistischen Momente höherer Ordnung beschriebenen rippeninduzierten instationären Strömungsvorgänge sowie der diffusive Transport treten oberhalb der Rippen nur in einem schmalen Band auf.
Custom-Built Operant Conditioning Setup for Calcium Imaging and Cognitive Testing in Freely Moving Mice
Authors: Vassilev Philip , Fonseca Esmeralda , Hernandez Giovanni , Pantoja-Urban Andrea Haree , Giroux Michel , Nouel Dominique , Van Leer Elise , Flores Cecilia
Published: February 2022

Operant chambers are widely used in animal research to study cognition, motivation, and learning processes. Paired with the rapidly developing technologies for brain imaging and manipulations of brain activity, operant conditioning chambers are a powerful tool for neuroscience research. The behavioral testing and imaging setups that are commercially available are often quite costly. Here, we present a custom-built operant chamber that can be constructed in a few days by an unexperienced user with relatively inexpensive, widely available materials. The advantages of our operant setup compared with other open-source and closed-source solutions are its relatively low cost, its support of complex behavioral tasks, its user-friendly setup, and its validated functionality with video imaging of behavior and calcium imaging using the UCLA Miniscope. Using this setup, we replicate our previously published findings showing that mice exposed to social defeat stress in adolescence have inhibitory control impairments in the Go/No-Go task when they reach adulthood. We also present calcium imaging data of medial prefrontal cortex (mPFC) neuronal activity acquired during Go/No-Go testing in freely moving mice and show that neuronal population activity increases from day 1 to day 14 of the task. We propose that our operant chamber is a cheaper alternative to its commercially available counterparts and offers a better balance between versatility and user-friendly setup than other open-source alternatives.
Kinetics and Connectivity Properties of Parvalbumin- and Somatostatin-Positive Inhibition in Layer 2/3 Medial Entorhinal Cortex
Authors: Fernandez Fernando R. , Via Guillem , Canavier Carmen C. , White John A.
Published: February 2022

Parvalbumin-positive (Pvalb+) and somatostatin-positive (Sst+) cells are the two largest subgroups of inhibitory interneurons. Studies in visual cortex indicate that synaptic connections between Pvalb+cells are common while connections between Sst+interneurons have not been observed. The inhibitory connectivity and kinetics of these two interneuron subpopulations, however, have not been characterized in medial entorhinal cortex (mEC). Using fluorescence-guided paired recordings in mouse brain slices from interneurons and excitatory cells in layer 2/3 mEC, we found that, unlike neocortical measures, Sst+cells inhibit each other, albeit with a lower probability than Pvalb+cells (18% vs 36% for unidirectional connections). Gap junction connections were also more frequent between Pvalb+cells than between Sst+cells. Pvalb+cells inhibited each other with larger conductances, smaller decay time constants, and shorter delays. Similarly, synaptic connections between Pvalb+and excitatory cells were more likely and expressed faster decay times and shorter delays than those between Sst+and excitatory cells. Inhibitory cells exhibited smaller synaptic decay time constants between interneurons than on their excitatory targets. Inhibition between interneurons also depressed faster, and to a greater extent. Finally, inhibition onto layer 2 pyramidal and stellate cells originating from Pvalb+interneurons were very similar, with no significant differences in connection likelihood, inhibitory amplitude, and decay time. A model of short-term depression fitted to the data indicates that recovery time constants for refilling the available pool are in the range of 50–150 ms and that the fraction of the available pool released on each spike is in the range 0.2–0.5.
Neurons in the Monkey's Subthalamic Nucleus Differentially Encode Motivation and Effort
Authors: Nougaret Simon , Baunez Christelle , Ravel Sabrina
Published: February 2022

The understanding of the electrophysiological properties of the subthalamic nucleus (STN) neurons is crucial since it represents the main target of deep brain stimulation for the treatment of Parkinson's disease and obsessive-compulsive disorders. The study of its nonmotor properties could shed light on the cognitive and motivational alterations possibly encountered after stimulation. In this study, we recorded the activity of STN neurons in two male behaving monkeys (Macaca mulatta) while they performed a visuomotor motivational task in which visual cues indicated which amount of force was required to obtain which amount of reward. Our results evidenced force- and reward-modulated neurons. After the occurrence of the visual stimuli, the force-modulated neurons mainly fired when a high effort was required. Differently, the activity of the population of reward-modulated neurons encoded the motivational value of the stimuli. This population consisted of neurons increasing or decreasing their activity according to the motivational ranking of the task conditions. Both populations could play complementary roles, one in the implementation of the difficulty of the action and the other in enhancing or slowing its execution based on the subjective value of each condition.

SIGNIFICANCE STATEMENTAn increasing number of studies confers a role to the subthalamic nucleus (STN) in motivational and reward-related processes. However, the electrophysiological bases of such properties at the neuronal level remain unclear. The present study investigated the modulation of STN neuronal activity in monkeys performing a motivational task in which the force to produce and the reward obtained were manipulated. We found two main populations of neurons, one modulated by the effort required and the other integrating the motivational subjective value of the stimuli. This last population could help at improving decision-making to act or not, depending on the subjective value set by the motivational context. This highlights the pivotal role of STN in the valuation of cost/benefit for decision-making processes.
The Struggle for Memory and Justice in Mexico
Authors: Alonso Alexandra Délano , Nienass Benjamin
Published: February 2022

The debate about public memory has intensified in Mexico in a time of widespread violence and human rights abuses, particularly in the context of the guerra contra el narco (war against drug cartels) that began in 2006. Confronting government narratives that criminalize victims of enforced disappearance and criminal violence, and the state’s failure to bring the perpetrators to justice, families of victims and other activists have led a struggle for truth, justice, memory and reparations. Through diverse memorial interventions across the country, they call attention to the continuities in state violence over time, and the need for memorial spaces that transform the structural conditions underlying different forms of violence and state neglect.
Neglect and Resistance in Brazil’s Pandemic
Authors: Nunes João
Published: February 2022

This article uses the lens of neglect to analyze Brazil’s response to the COVID-19 pandemic. It argues that the neglect of COVID-19 was the result of a mixture of omissions, obstructions and actions on the part of the federal government and President Jair Bolsonaro. It also suggests that addressing Brazil’s handling of the pandemic as simply a matter of governmental failure risks overlooking the multiple forms of resistance and struggle that emerged as social forces mobilized and sought to push back against the state’s neglect.