bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of temperature and pressure on the threshold value of SBS LIDAR in seawater
Authors: Shi Jiulin , Yuan Dapeng , Xu Jin , Guo Yangning , Luo Ningning , Li Shujing , He Xingdao
Published: December 2020

Effects of temperature and pressure on the threshold value of stimulated Brillouin scattering (SBS) in seawater were analyzed theoretically and experimentally. Theoretically, the change of threshold value of SBS versus the ocean depth was simulated based on the International Thermodynamic Equation of Seawater-2010 (TEOS-10) and the World Ocean Atlas 2013 (WOA13). Experimentally, an ocean temperature and pressure simulator (OTPS) was designed to measure the threshold value of SBS through simulating the changes of temperature and pressure of seawater in 0∼1000 meters. The theoretical and experimental results exhibit that the threshold value of SBS decreases with the increase of temperature at the same seawater pressure and increases with the increase of pressure at the same seawater temperature. The results imply that the SBS process is more likely to occur in upper seawater of lower-latitude areas. The theoretical and experimental results are helpful for remote sensing in ocean using the SBS LIDAR.
Strong visible-light emission in annealed poly(acrylic acid)
Authors: Tarekegne Abebe T. , Janting Jakob , Ou Haiyan
Published: December 2020

An intense and broadband photoluminescence emission is demonstrated in a bio-compatible film produced by thermal annealing of poly(acrylic acid) (PAA). The annealing process enhances the emission intensity from weakly emitting sub-luminophores of C–O and C=O functional groups by a factor of more than two orders of magnitude. The emission property can be sensitively tuned by the annealing temperature, duration, the PAA solution preparation conditions such as solvent type and solvent:PAA ratio. The strong luminescence is attributed to the formation of rigid molecular structure due to aggregation and crosslinking. FTIR measurements show that the aggregation and crosslinking processes subdue nonradiative recombination pathways.
Numerical and analytical approaches to dynamic beam waist optimization for LEO-to-GEO laser communication
Authors: Do Phong Xuan , Carrasco-Casado Alberto , Vu Tan Van , Hosonuma Takayuki , Toyoshima Morio , Nakasuka Shinichi
Published: December 2020

We study a dynamic scheme for optimizing the beam waist in low earth orbit-to-geostationary orbit (LEO-to-GEO) laser communication for small satellites under the influence of the pointing error on the transmitting side. Using the Marcum Q-function, we express the channel gain of the link in a closed form. Based on this expression, we obtain an accurate approximation of the optimal value of the laser beam waist via both numerical and analytical approaches to achieve the minimal average bit error probability (ABEP) of the LEO-to-GEO communication. The analytical approximation has a simple form and can be straightforwardly calculated and employed in practice. We numerically compute the ABEP with our analytical solution and the sub-optimal solution proposed in the literature. The results show a strong agreement between our solution and previous work.
Neural diffusivity and pre-emptive epileptic seizure intervention
Authors: Fagerholm Erik D. , Tangwiriyasakul Chayanin , Friston Karl J. , Violante Inês R. , Williams Steven , Carmichael David W. , Perani Suejen , Turkheimer Federico E. , Moran Rosalyn J. , Leech Robert , Richardson Mark P.
Published: December 2020

The propagation of epileptic seizure activity in the brain is a widespread pathophysiology that, in principle, should yield to intervention techniques guided by mathematical models of neuronal ensemble dynamics. During a seizure, neural activity will deviate from its current dynamical regime to one in which there are significant signal fluctuations. In silico treatments of neural activity are an important tool for the understanding of how the healthy brain can maintain stability, as well as of how pathology can lead to seizures. The hope is that, contained within the mathematical foundations of such treatments, there lie potential strategies for mitigating instabilities, e.g. via external stimulation. Here, we demonstrate that the dynamic causal modelling neuronal state equation generalises to a Fokker-Planck formalism if one extends the framework to model the ways in which activity propagates along the structural connections of neural systems. Using the Jacobian of this generalised state equation, we show that an initially unstable system can be rendered stable via a reduction in diffusivity–i.e., by lowering the rate at which neuronal fluctuations disperse to neighbouring regions. We show, for neural systems prone to epileptic seizures, that such a reduction in diffusivity can be achieved via external stimulation. Specifically, we show that this stimulation should be applied in such a way as to temporarily mirror the activity profile of a pathological region in its functionally connected areas. This counter-intuitive method is intended to be used pre-emptively–i.e., in order to mitigate the effects of the seizure, or ideally even prevent it from occurring in the first place. We offer proof of principle using simulations based on functional neuroimaging data collected from patients with idiopathic generalised epilepsy, in which we successfully suppress pathological activity in a distinct sub-network prior to seizure onset. Our hope is that this technique can form the basis for future real-time monitoring and intervention devices that are capable of treating epilepsy in a non-invasive manner.
Fate of antibiotic resistant E. coli and antibiotic resistance genes during full scale conventional and advanced anaerobic digestion of sewage sludge
Authors: Redhead Sky , Nieuwland Jeroen , Esteves Sandra , Lee Do-Hoon , Kim Dae-Wi , Mathias Jordan , Cha Chang-Jun , Toleman Mark , Dinsdale Richard , Guwy Alan , Hayhurst Emma
Published: December 2020

Antibiotic resistant bacteria (ARB) and their genes (ARGs) have become recognised as significant emerging environmental pollutants. ARB and ARGs in sewage sludge can be transmitted back to humans via the food chain when sludge is recycled to agricultural land, making sludge treatment key to control the release of ARB and ARGs to the environment. This study investigated the fate of antibiotic resistant Escherichia coli and a large set of antibiotic resistance genes (ARGs) during full scale anaerobic digestion (AD) of sewage sludge at two U.K. wastewater treatment plants and evaluated the impact of thermal hydrolysis (TH) pre-treatment on their abundance and diversity. Absolute abundance of 13 ARGs and the Class I integron gene intI1 was calculated using single gene quantitative (q) PCR. High through-put qPCR analysis was also used to determine the relative abundance of 370 ARGs and mobile genetic elements (MGEs). Results revealed that TH reduced the absolute abundance of all ARGs tested and intI1 by 10–12,000 fold. After subsequent AD, a rebound effect was seen in many ARGs. The fate of ARGs during AD without pre-treatment was variable. Relative abundance of most ARGs and MGEs decreased or fluctuated, with the exception of macrolide resistance genes, which were enriched at both plants, and tetracyline and glycopeptide resistance genes which were enriched in the plant employing TH. Diversity of ARGs and MGEs decreased in both plants during sludge treatment. Principal coordinates analysis revealed that ARGs are clearly distinguished according to treatment step, whereas MGEs in digested sludge cluster according to site. This study provides a comprehensive within-digestor analysis of the fate of ARGs, MGEs and antibiotic resistant E. coli and highlights the effectiveness of AD, particularly when TH is used as a pre-treatment, at reducing the abundance of most ARGs and MGEs in sludgeand preventing their release into the environment.
Associations of body mass index and waist circumference with risk of Guillain-Barré syndrome in women and men: A prospective analysis of three cohort studies
Authors: Ding Ming , Markon Andre , Wolpert Beverly , Chavarro Jorge E.
Published: December 2020

Background

The association of body mass index (BMI) and waist circumference (WC) with risk of Guillain-Barré syndrome (GBS) has been inconsistent in previous studies.

Methods

We examined the associations of BMI and WC in relation to risk of GBS among 252,980 participants from the Nurses’ Health Study (NHS), NHS-II, and the Health Professional Follow-up Study (HPFS). BMI and WC were assessed by self-reported questionnaire, and GBS cases were self-reported.

Results

We documented 328 incident GBS cases during a total of 5,422,788 person years of follow-up. Compared to participants with BMI<25kg/m2, the multivariate pooled hazard ratio (HR) of GBS was 1.34 (95% CI: 1.04, 1.73) for overweight participants (25kg/m2≤BMI<30 kg/m2), and 1.68 (95% CI: 1.21, 2.35) for obese participants (BMI≥30 kg/m2) (P for trend = 0.001). Compared to participants with normal WC (<35 inches for women and <40 inches for men), the HR of GBS was 1.55 (95% CI: 1.10, 2.18) for participants with high WC (≥35 inches for women, and ≥40 inches for men). The positive associations of BMI and WC with risk of GBS were attenuated to null after mutually adjusting for BMI and WC. Joint analysis showed that the HR was 1.84 (95% CI: 1.27, 2.66) for participants with high WC and BMI≥25 kg/m2 in comparison to participants with normal WC and BMI<25kg/m2.

Conclusion

These data from large cohorts showed that higher BMI and WC jointly were associated with higher risk of GBS. Our study highlighted the importance of maintaining a normal body weight and waist circumference in prevention of GBS.
Prosaposin and its receptors GRP37 and GPR37L1 show increased immunoreactivity in the facial nucleus following facial nerve transection
Authors: Kunihiro Joji , Nabeka Hiroaki , Wakisaka Hiroyuki , Unuma Kana , Khan Md. Sakirul Islam , Shimokawa Tetsuya , Islam Farzana , Doihara Takuya , Yamamiya Kimiko , Saito Shouichiro , Hamada Fumihiko , Matsuda Seiji
Published: December 2020

Neurotrophic factor prosaposin (PS) is a precursor for saposins A, B, C, and D, which are activators for specific sphingolipid hydrolases in lysosomes. Both saposins and PS are widely contained in various tissues. The brain, skeletal muscle, and heart cells predominantly contain unprocessed PS rather than saposins. PS and PS-derived peptides stimulate neuritogenesis and increase choline acetyltransferase activity in neuroblastoma cells and prevent programmed cell death in neurons. We previously detected increases in PS immunoactivity and its mRNA in the rat facial nucleus following facial nerve transection. PS mRNA expression increased not only in facial motoneurons, but also in microglia during facial nerve regeneration. In the present study, we examined the changes in immunoreactivity of the PS receptors GPR37 and GPR37L1 in the rat facial nucleus following facial nerve transection. Following facial nerve transection, many small Iba1- and glial fibrillary acidic protein (GFAP)-positive cells with strong GPR37L1 immunoreactivity, including microglia and astrocytes, were observed predominately on the operated side. These results indicate that GPR37 mainly works in neurons, whereas GPR37L1 is predominant in microglia or astrocytes, and suggest that increased PS in damaged neurons stimulates microglia or astrocytes via PS receptor GPR37L1 to produce neurotrophic factors for neuronal recovery.
Perturbation of the human gastrointestinal tract microbial ecosystem by oral drugs to treat chronic disease results in a spectrum of individual specific patterns of extinction and persistence of dominant microbial strains
Authors: Koo Hyunmin , Morrow Casey D.
Published: December 2020

Background

Oral drugs can have side effects such as diarrhea that indicate the perturbation of the gut microbial community. To further understand the dynamics of perturbation, we have assessed the strain relatedness of samples from previously published data sets from pre and post bowel evacuation, episodes of diarrhea, and administration of oral drugs to treat diabetes and rheumatoid arthritis.

Methods

We analyzed a total of published five data sets using our strain-tracking tool called Window-based Single Nucleotide Variant (SNV) Similarity (WSS) to identify related strains from the same individual.

Results

Strain-tracking analysis using the first data set from 8 individuals pre and 21–50 days post iso-osmotic bowel wash revealed almost all microbial strains were related in an individual between pre and post samples. Similarly, in a second study, strain-tracking analysis of 4 individuals pre and post sporadic diarrhea revealed the majority of strains were related over time (up to 44 weeks). In contrast, the analysis of a third data set from 22 individuals pre and post 3-day exposure of oral metformin revealed that no individuals had a related strain. In a fourth study, the data set taken at 2 and 4 months from 38 individuals on placebo or metformin revealed individual specific sharing of pre and post strains. Finally, the data set from 18 individuals with rheumatoid arthritis given disease-modifying antirheumatic drugs methotrexate or glycosides of the traditional Chinese medicinal componentTripterygium wilfordiishowed individual specific sharing of pre and post strains up to 16 months.

Conclusion

Oral drugs used to treat chronic disease can result in individual specific microbial strain change for the majority of species. Since the gut community provides essential functions for the host, our study supports personalized monitoring to assess the status of the dominant microbial strains after initiation of oral drugs to treat chronic disease.
Acuities into tolerance mechanisms via different bioassay during Brassicaceae-Alternaria brassicicola interaction and its impact on yield
Authors: Munir Sana , Shahzad Ahmad Naeem , Qureshi Muhammad Kamran
Published: December 2020

Heavy losses by dark leaf spot disease in oilseedBrassicahave incited research towards identifying sources of genetic tolerance against causal pathogen,Alternaria brassicicola. Several morpho-molecular parameters were evaluated to test the performance of field mustard and rapeseed genotypes under artificial inoculation with this pathogen. DuringBrassica-Alternariainteraction, physio-biochemical defense response was witnessed in tolerant genotypes. Two tolerant genotypes (one for field mustard and one for rapeseed), i.e., EC250407 and EC1494 were identified. However, necrotic lesions were more prominent in susceptible genotypes with minimum chlorophyll (chlorophylla, chlorophyllband total chlorophyll) and carotenoids contents. Contrary to photosynthetic pigments, increase in total soluble protein (TSP) contents was observed with disease progression in susceptible genotypes. Tolerant genotypes of field mustard and rapeseed displayed remarkable increase in the activities of redox enzyme in infected leaves with least yield loss (6.47% and 5.74%) and disease severity index (DSI) of 2.9 and 2.1, respectively. However, yield/plant showed close association with other morpho-yield parameters, photosynthetic pigments and redox enzymes (superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD)) activities except silique length and TSP. Based on the results of morpho-biochemical analyses, redox enzymes and morphological parameters; their interplay is proposed to determine the tolerance outcome of theBrassica-A.brassicicolainteraction.
Voluntary adoption of social welfare-enhancing behavior: Mask-wearing in Spain during the COVID-19 outbreak
Authors: Barceló Joan , Sheen Greg Chih-Hsin
Published: December 2020

With the spread of COVID-19, more countries now recommend their citizens to wear facemasks in public. The uptake of facemasks, however, remains far from universal in countries where this practice lacks cultural roots. In this paper, we aim to identify the barriers to mask-wearing in Spain, a country with no mask-wearing culture. We conduct one of the first nationally representative surveys (n = 4,000) about this unprecedented public health emergency and identify the profile of citizens who are more resistant to face-masking: young, educated, unconcerned with being infected, and with an introverted personality. Our results further indicate a positive correlation between a social norm of mask-wearing and mask uptake and demonstrate that uptake of facemasks is especially high among the elderly living in localities where mask-wearing behavior is popular. These results are robust when controlling for respondents’ demographics, time spent at home, and occupation fixed effects. Our findings can be useful for policymakers to devise effective programs for improving public compliance.
Qualitative program evaluation of social determinants of health screening and referral program
Authors: Emengo Vivian N. , Williams Myia S. , Odusanya Rachael , Uwemedimo Omolara T. , Martinez Johanna , Pekmezaris Renee , Kim Eun Ji
Published: December 2020

Although the integration of social determinants of health (SDH) screening and referral programs in clinical settings has rapidly grown, the voice and experience of participants within SDH programs has not been well understood in program evaluations. To qualitatively evaluate a comprehensive SDH screening and referral program based in an academic primary care setting, we conducted a qualitative analysis of a semi-structured, focus group interview of 7 caregivers. We performed inductive coding representing emerging ideas from each transcript using focus group transcripts from families who participated in the SDH screening and referral program. A thematic model was created describing caregivers’ experiences with respect to screening, intake, and referral phases of the program. Caregivers reported satisfaction with structural and process-related components of screening, intake, and referral. They expressed a preference for trained patient navigators over physicians for screening and intake for they were perceived to have time to prioritize caregivers’ social needs. Caregivers reported disappointment with legal services screening, intake, and referral, citing lack of timely contact from the legal resource team and prematurity of provided legal resources. Overall, caregivers recommend the program, citing that the program provided social support, an environment where expression is encouraged, motivation to address their own health needs, and a convenient location. Overall, caregivers would recommend the program because they feel socially supported. The use of trained patient navigators appears to be instrumental to the successful implementation of the program in clinics, for navigators can provide caregivers with the appropriate time and personal attention they need to complete the survey and discuss their needs. Streamlining the referral process for evaluation of health-harming needs by the medical legal partnership was highlighted as an area for improvement.
What determines employment quality among people living with HIV: An empirical study in China
Authors: Yu Yunjiang , Chen Zhi , Huang Shenglan , Chen Zhicheng , Zhang Kailin
Published: December 2020

At the intersection of research areas on health and employment, little attention has been paid on employment quality among people living with HIV (PLWH). The objective of the current study is to identify critical factors and empirically examine their effects on employment quality among PLWH. Based on the social-ecological perspective, we identified negative self-image, workplace discrimination, social support, and policy support as critical factors associated with employment quality among PLWH. Thereafter, a questionnaire survey was conducted to gather information from 339 employed PLWH in China. Hierarchical regression analyses were further performed to analyze the effects of the identified factors on employment quality among PLWH. We obtained three main findings. First, negative self-image and workplace discrimination are detrimental to employment quality among PLWH; whereas social support and policy support are conducive to their employment quality. Second, older, male, and highly educated PLWH can better leverage the undesirable effects of negative self-image and workplace discrimination on employment quality compared with their peers. Third, male, and highly educated PLWH can better utilize social support and policy support to advance employment quality compared with their peers. However, the employment quality effects of the identified factors did not differ by marital status. Our findings provided some useful implications for PLWH, employers, community service providers, and policy makers to promote employment quality among PLWH.
Di-arginine and FFAT-like motifs retain a subpopulation of PRA1 at ER-mitochondria membrane contact sites
Authors: Abu Irqeba Ameair , Ogilvie Judith Mosinger
Published: December 2020

Prenylated Rab Acceptor 1 (PRA1/Rabac1) is a four-pass transmembrane protein that has been found to localize to the Golgi and promiscuously associate with a diverse array of Rab GTPases. We have previously identified PRA1 to be among the earliest significantly down-regulated genes in the rd1 mouse model of retinitis pigmentosa, a retinal degenerative disease. Here, we show that an endogenous subpopulation of PRA1 resides within the endoplasmic reticulum (ER) at ER-mitochondria membrane contact sites in cultured mammalian cells. We also demonstrate that PRA1 contains two previously unidentified ER retention/retrieval amino acid sequences on its cytosolic N-terminal region: a membrane distal di-arginine motif and a novel membrane proximal FFAT-like motif. Using a truncation construct that lacks complete Golgi targeting information, we show that mutation of either motif leads to an increase in cell surface localization, while mutation of both motifs exhibits an additive effect. We also present evidence that illustrates that N- or C- terminal addition of a tag to full-length PRA1 leads to differential localization to either the Golgi or reticular ER, phenotypes that do not completely mirror endogenous protein localization. The presence of multiple ER retention motifs on the PRA1 N-terminal region further suggests that it has a functional role within the ER.
A study of the impact of citizenship education in Morocco
Authors: Benzehaf Bouchaib
Published: December 2020

Global changes taking place in today’s world have brought about an unprecedented crisis in citizenship values. For instance, violence, conflict and radicalization have become rampant in our society. Such crisis has brought to the limelight the role of education in sensitizing students about their rights and duties in order to promote peace, tolerance and mutual respect. In Morocco, educational reforms have given much importance to citizenship education in the belief that it can help raise students’ awareness about their rights and duties, anchor them to their communities, and provide them with the knowledge and skills necessary for active participation in society. The National Charter for Education and Training and the Higher Council for Education, Training and Scientific Research have created a roadmap for citizenship education. This study aims to investigate the impact of such attempts to train good citizens. The participants are 73 semester-two students of the department of English from the faculty of humanities, Chouaib Doukkali University. The main data collection tool is questionnaires. The data obtained are fed into SPSS to generate frequencies besides identifying main themes obtained from answers to open-ended questions. Findings show that the impact of such educational reforms is rather limited. While the majority of students expressed their feeling of belonging to their community as well as an accepted level of awareness of their rights and duties, they failed to act on the self-reported qualities of a good citizen. Such low level of engagement in their community affairs betrays weak links between students and their communities. In light of these findings, several recommendations are made to improve citizenship education and reduce the gap between the goals of national educational reforms and their actual implementation in schools. One such recommendation is that textbooks need to emphasize critical thinking and analysis so that students are empowered to become critical thinking global citizens and agents of change.
Glucagon-Like Peptide 2 Inhibits Postprandial Gallbladder Emptying in Man: A Randomized, Double-Blinded, Crossover Study
Authors: Hansen Nina L. , Brønden Andreas , Nexøe-Larsen Christina C. , Christensen Alexander S. , Sonne David P. , Rehfeld Jens F. , Wever Albretchsen Nicolai J. , Hartmann Bolette , Vilsbøll Tina , Holst Jens J. , Knop Filip K.
Published: December 2020

INTRODUCTION:

A recent study in mice points to the gut-derived hormone glucagon-like peptide 2 (GLP-2) as an important regulator of gallbladder motility inducing gallbladder relaxation and refilling. In this study, we evaluated the effect of exogenous GLP-2 on postprandial gallbladder motility in healthy men.

METHODS:

In a randomized, double-blinded, placebo-controlled, crossover study, we evaluated the effect of 4-hour intravenous infusions of high-dose GLP-2 (10 pmol × kg−1 × min−1), low-dose GLP-2 (1 pmol × kg−1 × min−1), and placebo (saline) on postprandial gallbladder motility. A 300-kcal liquid-mixed meal (added 1.5 g of acetaminophen for indirect measurement of gastric emptying) was served 30 minutes after start of intravenous infusions. Gallbladder volume was assessed by ultrasonography.

RESULTS:

Fifteen healthy men, age 24.3 (22.4–26.1) years (mean [95% confidence interval]) and body mass index 22.5 (21.7–23.4) kg × m−2, were included. Basal plasma GLP-2 concentration was 14 (11–17) pmol/L. During low-dose and high-dose GLP-2 infusions, steady-state postprandial plasma GLP-2 concentrations amounted to 201 (188–214) and 2,658 (2,443–2,873) pmol/L, respectively, compared with maximum postprandial plasma GLP-2 concentration of 34 (25–44) pmol/L during placebo. Gallbladder emptying (assessed as baseline-subtracted area under the curve for gallbladder volume) was reduced by low-dose GLP-2 (−0.8 [0.7–1.9] L × min, P < 0.0001) and nearly abolished by high-dose GLP-2 (1.3 [−1.7 to 0.01] L × min, P = 0.029) compared to placebo (−2.0 [−2.8 to −1.1] L × min). Compared to placebo, gastric emptying was reduced by high-dose GLP-2 (P = 0.0060 and 0.019), whereas low-dose GLP-2 did not affect gastric emptying (P = 0.13 and 0.85).

DISCUSSION:

Exogenous GLP-2 exerts a dose-dependent inhibitory effect on postprandial gallbladder emptying in healthy men.
HYDROCHEMICAL ANALYSIS OF A BASIN UNDER ANTHROPOGENIC INFLUENCE AND EFFECTS IN MANAUS’ SHORELINE - CENTRAL AMAZONIA
Authors: Del Rio Calvo Bruno , Cristina Souza de Oliveira Tereza
Published: December 2020

Estudo ambiental realizado na bacia do Educandos (Manaus-AM), que abrange grande quantidade de residências e o Pólo Industrial de Manaus (PIM), vem avaliar o impacto das atividades antrópicas nos igarapés dessa bacia e potenciais influências ao Rio Negro, na orla de Manaus. Foi determinado o pH, C.E., turbidez, temperatura, SST, ânions (HCO3-,NO3-, F-, Cl-, SO42- ) e metais (Ni2+, Pb2+, Cr3+, Cu2+, Fe2+,V+, Zn2+ e Al3+). Mensurou-se os ânions por CLAE, os metais por ICP-OES e demais parâmetros por métodos clássicos. Constatou-se alteração de todos os parâmetros nos igarapés pela atividade antropogênica. Observou-se que o igarapé do Quarenta não alterou significativamente os padrões de qualidade da água na orla do Rio Negro. Observou-se elevada degradação da foz dos igarapés do Cachoeirinha e Mestre Chico com os mais elevados níveis de Cl-, F-, SO42-, C.E., pH e HCO3-. Estes parâmetros foram mais altos que em décadas passadas, indicando um aumento de contaminação por esgotos. Locais ao lado do PIM apresentaram altos teores de Ni2+ e Al3+, decorrente da emissão industrial.  Os metais de Pb2+, Cr3+, Cu2+, V+ mantiveram-se adequados a legislação N° 357/2005 do CONAMA em todos os pontos de coleta, indicando possível redução da emissão de metais potencialmente tóxicos.
Non-Alkaloidal Compounds from Khat (Catha edulis) Leaves
Authors: Kiros Tsegu
Published: December 2020

Khat belongs to the family Celastraceae, genus Catha, and species edulis. More than 200 compounds have previously been identified in Khat leaves, including: 40 alkaloids, terpenoids and sterol, flavonoids, glycosides, tannins, amino acids, vitamins and minerals. Researchers have spent their effort and time merely on study of the alkaloidal components (mainly the stimulant agents, cathinone and cathine) of Khat both qualitatively and quantitatively. The two principal Khat stimulant compounds, cathinone and cathine, by now are well established. But, on the contrary, previous studies on the non-alkaloidal constituents of the plant were limited. The objective of this work was therefore to isolate and characterize compounds from non-alkaloidal fractions of the plant’s leaves.  In this work, two non-alkaloidal compounds (KNA-1 and KNA-2) were isolated and characterized from the acid-EtOAc extract of fresh and oven-dried leaves of Khat (Catha edulis). From the present study, it is possible to conclude that investing more effort and time on searching additional non-alkaloidal principles from the leaves of Khat is so necessary. And further works could be done in the future to isolate extra non-alkaloidal compounds from the leaves and other parts of Khat and evaluate their biological activity.
Avances y desafíos de métodos y modelos computacionales aplicados al análisis de información en redes sociales
Authors: Diaz Mendivelso Johan David , Suárez Barón Marco Javier
Published: December 2020

Este artículo presenta la revisión de la literatura científica dirigida al estudio y análisis del estado actual de investigaciones relacionadas con la aplicación de métodos y modelos para el análisis social en entornos digitales, los cuales faciliten el descubrimiento de conocimiento a partir de la gestión de información contenida en redes sociales de tipo corporativo. El estudio explora temas relacionados con la extracción de información útil y análisis de cadenas textuales utilizando técnicas de indexación semántica latente apoyadas por el procesamiento del lenguaje natural (PLN). Para la revisión, se aplicó una metodología basada en el planteamiento de palabras clave que funcionen como insumo en la búsqueda de documentación en bases de datos indexadas y fuentes primarias; los documentos resultantes se filtran en un análisis detallado que se realiza individualmente, seleccionando así las mejores fuentes para plantear una revisión técnica. Por último, se plantean algunos resultados y trabajos futuros para garantizar el inicio de nuevas investigaciones.

Al realizar la revisión planteada, se detecta que investigaciones de este tipo establecen un camino apropiado para las organizaciones empresariales y sociales, dando estrategias computacionales para descubrir conocimiento a través de técnicas de visualización de patrones, los cuales ayudan a la toma de decisiones sobre I+D+i y permiten garantizar el desarrollo y avance de planes operativos. Se justifica la necesidad de realizar y llevar a cabo proyectos relacionados con temas de análisis de información que se encuentra en entornos virtuales como lo son las redes sociales, aplicando técnicas de PLN y modelos I+D+i; con lo anterior, se podría dar vía libre para el planteamiento de nuevos proyectos que pertenezcan al área de conocimiento.
EXPLORATION OF BANDUNG THROUGH ANHOLT HEXAGONAL CITY BRAND SUSTAINED BY CORN AGRIBUSINESS IN ARJASARI DISTRICT
Authors: Gandakusumah Beryl , Marta Rustono Farady
Published: December 2020

West Java as a province with the largest population that oversees many cities, one of which is that Bandung should be able to contribute to the Indonesian economy through the development of aspects of the image of a city which can also be called a city brand. This research will look at the forming components of Bandung, especially the Arjasari region which has not been maximized and can be improved, so as to create a good creative economic development in the Arjasari region and can be socially economically positive for the Arjasari community and the Indonesian people. The research was carried out with a qualitative approach through observations that are analyzed with hexagonal city brand components which are reinforced with literature study data. Through competitive strategies by developing various aspects of forming an area, the Arjasari Region can become a socially advanced region through agricultural products in the form of corn.
Form and Function of Aizuchi Japenese Native Speaker in Inaka Ni Tomarou! TV Serial
Authors: Dityandari Iantika Humanjadna , Aryanto Bayu
Published: December 2020

This study is intended to describe the form of aizuchi in the TV series Inaka Ni Tomarou! and find out the function of Aizuchi's speech based on the conversation context. The research data are the forms of aizuchi, which are used in a conversational context. This type of research is a qualitative descriptive study. The researchers found six forms of aizuchi: short speech, interjection speech, interjection, and short utterances, repeated short utterances, repeated speech partner utterance, short utterances, and repetition of speech partners. In the function, Aizuchi has seven functions: a continuer signal, an understanding signal, an approval signal, a signal indicating emotion, a signal to confirm, a rejection signal, and a filling signal.
The dark side of the Empire: Roman expansionism between object agency and predatory regime
Authors: Fernández-Götz Manuel , Maschek Dominik , Roymans Nico
Published: December 2020

This debate piece offers a critique of some recent ‘new materialist’ approaches and their application to Roman expansionism, particularly those positing that the study of ‘Romanisation’ should be about ‘understanding objects in motion’—a perspective that carries important political and ethical implications. Here, the authors introduce the alternative notion of a ‘predatory’ political economy for conceptualising Late Republican and Early Imperial Rome. The aim is to illuminate the darker sides of Roman expansionism in order to produce more balanced and inclusive accounts. Two cases studies—the archaeology of the Roman conquest and of rural communities—illustrate the potential of such a perspective.
Twenty-Five Years of Research Using Implicit Measures
Authors: Gawronski Bertram , De Houwer Jan , Sherman Jeffrey W.
Published: December 2020

The year 2020 marks the 25th anniversary of two seminal publications that have set the foundation for an exponentially growing body of research using implicit measures: Fazio, Jackson, Dunton, and Williams's (1995) work using evaluative priming to measure racial attitudes, and Greenwald and Banaji's (1995) review of implicit social cognition research that served as the basis for the development of the Implicit Association Test (IAT). The current article provides an overview of (1) two conceptual roots that continue to shape interpretations of implicit measures; (2) conflicting interpretations of the term implicit; (3) different kinds of dissociations between implicit and explicit measures; (4) theoretical developments inspired by these dissociations; and (5) research that used implicit measures to address domain-specific and applied questions. We conclude with a discussion of challenges and open questions that remain to be addressed, offering guidance for the next generation of research using implicit measures.
Applied Racial/Ethnic Healthcare Disparities Research Using Implicit Measures
Authors: Hagiwara Nao , Dovidio John F. , Stone Jeff , Penner Louis A.
Published: December 2020

Many healthcare disparities studies use the Implicit Association Test (IAT) to assess bias. Despite ongoing controversy around the IAT, its use has enabled researchers to reliably document an association between provider implicit prejudice and provider-to-patient communication (provider communication behaviors and patient reactions to them). Success in documenting such associations is likely due to the outcomes studied, study settings, and data structure unique to racial/ethnic healthcare disparities research. In contrast, there has been little evidence supporting the role of providers’ implicit bias in treatment recommendations. Researchers are encouraged to use multiple implicit measures to further investigate how, why, and under what circumstances providers’ implicit bias predicts provider-to-patient communication and treatment recommendations. Such efforts will contribute to the advancement of both basic social psychology/social cognition research and applied health disparities research: a better understanding of implicit social cognition and a more comprehensive identification of the sources of widespread racial/ethnic healthcare disparities, respectively.
The Case for Studying Implicit Social Cognition in Close Relationships
Authors: Faure Ruddy , McNulty James K. , Hicks Lindsey L. , Righetti Francesca
Published: December 2020

This review offers close relationships as a fruitful avenue to address long-lasting questions and current controversies in implicit social cognition research. Close relationships provide a unique opportunity to study strong attitudes that are formed and updated through ongoing contact with significant others and appear to have important downstream consequences. Therefore, close relationship contexts enable researchers to apply fine-grained, dyadic, longitudinal methodologies to provide unique insights regarding whether and how automatic attitudes relate to personal experience, change meaningfully and reliably over time, and predict consequential judgments and behaviors. Further, given that close relationships are critical to people's well-being and health, applying implicit social cognition theories to close relationships may also offer practical benefits regarding real-world issues related to relationship decay. In this regard, we provide guidance for future research by highlighting how continuing to refine our understanding of implicit social cognition in close relationships can inform interventions and reliably benefit society
Naturalistic Language Input is Associated with Resting-State Functional Connectivity in Infancy
Authors: King Lucy S. , Camacho M. Catalina , Montez David F. , Humphreys Kathryn L. , Gotlib Ian H.
Published: December 2020

The quantity and quality of the language input that infants receive from their caregivers affects their future language abilities; however, it is unclear how variation in this input relates to preverbal brain circuitry. The current study investigated the relation between naturalistic language input and the functional connectivity (FC) of language networks in human infancy using resting-state functional magnetic resonance imaging (rsfMRI). We recorded the naturalistic language environments of five- to eight-month-old male and female infants using the Linguistic ENvironment Analysis (LENA) system and measured the quantity and consistency of their exposure to adult words (AWs) and adult–infant conversational turns (CTs). Infants completed an rsfMRI scan during natural sleep, and we examined FC among regions of interest (ROIs) previously implicated in language comprehension, including the auditory cortex, the left inferior frontal gyrus (IFG), and the bilateral superior temporal gyrus (STG). Consistent with theory of the ontogeny of the cortical language network (Skeide and Friederici, 2016), we identified two subnetworks posited to have distinct developmental trajectories: a posterior temporal network involving connections of the auditory cortex and bilateral STG and a frontotemporal network involving connections of the left IFG. Independent of socioeconomic status (SES), the quantity of CTs was uniquely associated with FC of these networks. Infants who engaged in a larger number of CTs in daily life had lower connectivity in the posterior temporal language network. These results provide evidence for the role of vocal interactions with caregivers, compared with overheard adult speech, in the function of language networks in infancy.
The Architecture of Human Memory: Insights from Human Single-Neuron Recordings
Authors: Rutishauser Ueli , Reddy Leila , Mormann Florian , Sarnthein Johannes
Published: December 2020

Deciphering the mechanisms of human memory is a central goal of neuroscience, both from the point of view of the fundamental biology of memory and for its translational relevance. Here, we review some contributions that recordings from neurons in humans implanted with electrodes for clinical purposes have made toward this goal. Recordings from the medial temporal lobe, including the hippocampus, reveal the existence of two classes of cells: those encoding highly selective and invariant representations of abstract concepts, and memory-selective cells whose activity is related to familiarity and episodic retrieval. Insights derived from observing these cells in behaving humans include that semantic representations are activated before episodic representations, that memory content and memory strength are segregated, and that the activity of both types of cells is related to subjective awareness as expected from a substrate for declarative memory. Visually selective cells can remain persistently active for several seconds, thereby revealing a cellular substrate for working memory in humans. An overarching insight is that the neural code of human memory is interpretable at the single-neuron level. Jointly, intracranial recording studies are starting to reveal aspects of the building blocks of human memory at the single-cell level. This work establishes a bridge to cellular-level work in animals on the one hand, and the extensive literature on noninvasive imaging in humans on the other hand. More broadly, this work is a step toward a detailed mechanistic understanding of human memory that is needed to develop therapies for human memory disorders.
Hallucinogens in Mental Health: Preclinical and Clinical Studies on LSD, Psilocybin, MDMA, and Ketamine
Authors: De Gregorio Danilo , Aguilar-Valles Argel , Preller Katrin H. , Heifets Boris Dov , Hibicke Meghan , Mitchell Jennifer , Gobbi Gabriella
Published: December 2020

A revamped interest in the study of hallucinogens has recently emerged, especially with regard to their potential application in the treatment of psychiatric disorders. In the last decade, a plethora of preclinical and clinical studies have confirmed the efficacy of ketamine in the treatment of depression. More recently, emerging evidence has pointed out the potential therapeutic properties of psilocybin and LSD, as well as their ability to modulate functional brain connectivity. Moreover, MDMA, a compound belonging to the family of entactogens, has been demonstrated to be useful to treat post-traumatic stress disorders. In this review, the pharmacology of hallucinogenic compounds is summarized by underscoring the differences between psychedelic and nonpsychedelic hallucinogens as well as entactogens, and their behavioral effects in both animals and humans are described. Together, these data substantiate the potentials of these compounds in treating mental diseases.
Tet1Isoforms Differentially Regulate Gene Expression, Synaptic Transmission, and Memory in the Mammalian Brain
Authors: Greer C.B. , Wright J. , Weiss J.D. , Lazarenko R.M. , Moran S.P. , Zhu J. , Chronister K.S. , Jin A.Y. , Kennedy A.J. , Sweatt J.D. , Kaas G.A.
Published: December 2020

The dynamic regulation of DNA methylation in postmitotic neurons is necessary for memory formation and other adaptive behaviors. Ten-eleven translocation 1 (TET1) plays a part in these processes by oxidizing 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC), thereby initiating active DNA demethylation. However, attempts to pinpoint its exact role in the nervous system have been hindered by contradictory findings, perhaps due in part, to a recent discovery that two isoforms of theTet1gene are differentially expressed from early development into adulthood. Here, we demonstrate that both the shorter transcript (Tet1S) encoding an N-terminally truncated TET1 protein and a full-lengthTet1(Tet1FL) transcript encoding canonical TET1 are co-expressed in the adult mouse brain. We show thatTet1Sis the predominantly expressed isoform and is highly enriched in neurons, whereasTet1FLis generally expressed at lower levels and more abundant in glia, suggesting their roles are at least partially cell type-specific. Using viral-mediated, isoform and neuron-specific molecular tools, we find that the individual repression of each transcript leads to the dysregulation of unique gene ensembles and contrasting changes in basal synaptic transmission. In addition,Tet1Srepression enhances, whileTet1FLimpairs, hippocampal-dependent memory in male mice. Together, our findings demonstrate that eachTet1isoform serves a distinct role in the mammalian brain.

SIGNIFICANCE STATEMENTIn the brain, activity-dependent changes in gene expression are required for the formation of long-term memories. DNA methylation plays an essential role in orchestrating these learning-induced transcriptional programs by influencing chromatin accessibility and transcription factor binding. Once thought of as a stable epigenetic mark, DNA methylation is now known to be impermanent and dynamically regulated, driving neuroplasticity in the brain. We found thatTet1, a member of the ten-eleven translocation (TET) family of enzymes that mediates removal of DNA methyl marks, is expressed as two separate isoforms in the adult mouse brain and that each differentially regulates gene expression, synaptic transmission and memory formation. Together, our findings demonstrate that eachTet1isoform serves a distinct role in the CNS.
Heterogeneity of Age-Related Neural Hyperactivity along the CA3 Transverse Axis
Authors: Lee Heekyung , Wang Zitong , Zeger Scott L. , Gallagher Michela , Knierim James J.
Published: December 2020

Age-related memory deficits are correlated with neural hyperactivity in the CA3 region of the hippocampus. Abnormal CA3 hyperactivity in aged rats has been proposed to contribute to an imbalance between pattern separation and pattern completion, resulting in overly rigid representations. Recent evidence of functional heterogeneity along the CA3 transverse axis suggests that proximal CA3 supports pattern separation while distal CA3 supports pattern completion. It is not known whether age-related CA3 hyperactivity is uniformly represented along the CA3 transverse axis. We examined the firing rates of CA3 neurons from young and aged, male, Long–Evans rats along the CA3 transverse axis. Consistent with prior studies, young CA3 cells showed an increasing gradient in mean firing rate from proximal to distal CA3. However, aged CA3 cells showed an opposite, decreasing trend, in that CA3 cells in aged rats were hyperactive in proximal CA3, but possibly hypoactive in distal CA3, compared with young (Y) rats. We suggest that, in combination with altered inputs from the entorhinal cortex and dentate gyrus (DG), the proximal CA3 region of aged rats may switch from its normal function that reflects the pattern separation output of the DG and instead performs a computation that reflects an abnormal bias toward pattern completion. In parallel, distal CA3 of aged rats may create weaker attractor basins that promote abnormal, bistable representations under certain conditions.

SIGNIFICANCE STATEMENTPrior work suggested that age-related CA3 hyperactivity enhances pattern completion, resulting in rigid representations. Implicit in prior studies is the notion that hyperactivity is present throughout a functionally homogeneous CA3 network. However, more recent work has demonstrated functional heterogeneity along the CA3 transverse axis, in that proximal CA3 is involved in pattern separation and distal CA3 is involved in pattern completion. Here, we show that age-related hyperactivity is present only in proximal CA3, with potential hypoactivity in distal CA3. This result provides new insight in the role of CA3 in age-related memory impairments, suggesting that the rigid representations in aging result primarily from dysfunction of computational circuits involving the dentate gyrus (DG) and proximal CA3.