bluuebunny/crossref_metadata_2025 huggingface dataset:
Adaptive weight matrix and phantom intensity learning for computed tomography of chemiluminescence
Authors: Pan Hujie , Xiao Di , Zhang Fuhao , Li Xuesong , Xu Min
Published: June 2021

Classic algebraic reconstruction technique (ART) for computed tomography requires pre-determined weights of the voxels for the projected pixel values to build the equations. However, such weights cannot be accurately obtained in the application of chemiluminescence measurements due to the high physical complexity and computation resources required. Moreover, streaks arise in the results from ART method especially with imperfect projections. In this study, we propose a semi-case-wise learning-based method named Weight Encode Reconstruction Network (WERNet) to co-learn the target phantom intensities and the adaptive weight matrix of the case without labeling the target voxel set and thus offers a more applicable solution for computed tomography problems. Both numerical and experimental validations were conducted to evaluate the algorithm. In the numerical test, with the help of gradient normalization, the WERNet reconstructed voxel set with a high accuracy and showed a higher capability of denoising compared to the classic ART methods. In the experimental test, WERNet produces comparable results to the ART method while having a better performance in avoiding the streaks. Furthermore, with the adaptive weight matrix, WERNet is not sensitive to the ensemble intensity of the projection which shows much better robustness than ART method.
Generation of quantum states with nonlinear squeezing by Kerr nonlinearity
Authors: Bräuer Šimon , Marek Petr
Published: June 2021

In quantum optics, squeezing corresponds to the process in which fluctuations of a quadrature operator are reduced below the shot noise limit. In turn, nonlinear squeezing can be defined as reduction of fluctuations related to nonlinear combination of quadrature operators. Quantum states with nonlinear squeezing are a necessary resource for deterministic implementation of high-order quadrature phase gates that are, in turn, sufficient for advanced quantum information processing. We demonstrate that this class of states can be deterministically prepared by employing a single self-Kerr gate accompanied by suitable Gaussian processing. The required Kerr coupling depends on the energy of the initial system and can be made arbitrarily small. We also employ numerical simulations to analyze the effects of imperfections and to show to which extent can they be neglected.
Tailoring the efficiency and spectrum of a green random laser generated by frequency doubling of random fiber lasers
Authors: Wu Han , Liu Hongyu , Wang Weizhe , Wang Zinan , Liang Houkun
Published: June 2021

Frequency doubling of random fiber lasers could provide an effective way to realize visible random lasing with the spectrum filled with random frequencies. In this paper, we make a comprehensive study on the efficiency and spectral manipulation of a green random laser generated by frequency doubling of an ytterbium-doped random fiber laser (YRFL). To tailor the efficiency of green random lasing generation, the ytterbium-doped random fiber lasing is filtered at different spectral positions, and then amplified to watt-level to serve as the fundamental laser source for frequency doubling in a periodically poled lithium niobate (PPLN) crystal. We found that by selecting different spectral components of ytterbium-doped random fiber lasing, the temporal intensity fluctuations of the filtered radiations vary dramatically, which plays an important role in enhancing the efficiency of frequency doubling. By fixing the filtering radiation wavelength at 1064.5 nm and tuning the central wavelength of YRFL, we experimentally demonstrate that, compared to the filtered radiation in the center of the spectrum, the efficiency of frequency doubling can be nearly doubled by utilizing the filtered ytterbium-doped random fiber lasing in the wings of the spectrum. As a result, the conversion efficiency of the generated green random laser at 532.25 nm can be more than 11% when the input power of the polarized 1064.5 nm fundamental light is 2.85W. For spectral manipulation, we realize a spectral tunable green random laser in the range of 529.9 nm to 537.3 nm with >100 mW output power for the first time by tuning the wavelength of YRFL and the temperature of PPLN simultaneously. The system can be naturally modified to simultaneously realize the efficiency enhancement and wavelength tuning, thus providing a new route to generate high efficiency and tunable visible random laser via frequency doubling that are potentially useful for imaging, sensing and visible light communication applications.
Absolute calibration of a single-photon avalanche detector using a bright triggered single-photon source based on an InGaAs quantum dot
Authors: Georgieva Hristina , López Marco , Hofer Helmuth , Kanold Niklas , Kaganskiy Arsenty , Rodt Sven , Reitzenstein Stephan , Kück Stefan
Published: June 2021

We apply an InGaAs quantum dot based single-photon source for the absolute detection efficiency calibration of a silicon single-photon avalanche diode operating in Geiger mode. The single-photon source delivers up to (2.55 ± 0.02) × 106 photons per second inside a multimode fiber at the wavelength of 929.8 nm for above-band pulsed excitation with a repetition rate of 80 MHz. The purity of the single-photon emission, expressed by the value of the 2nd order correlation function g(2)(τ = 0), is between 0.14 and 0.24 depending on the excitation power applied to the quantum dot. The single-photon flux is sufficient to be measured with an analog low-noise reference detector, which is traceable to the national standard for optical radiant flux. The measured detection efficiency using the single-photon source remains constant within the measurement uncertainty for different photon fluxes. The corresponding weighted mean thus amounts to 0.3263 with a standard uncertainty of 0.0022.
Temperature-controlled terahertz polarization conversion bandwidth
Authors: Zhao Jing , Ouyang Chunmei , Chen Xieyu , Li Yanfeng , Zhang Caihong , Feng Longcheng , Jin Biaobing , Ma Jiajun , Liu Yi , Zhang Shoujun , Xu Quan , Han Jiaguang , Zhang Weili
Published: June 2021

Active control of metasurfaces has attracted widespread attention because of the adjustable electromagnetic properties obtained. Here we designed and experimentally studied a dynamically controllable polarization converter in the terahertz band. By designing the structural parameters and utilizing the insulator-to-metal phase transition of vanadium dioxide and principle of current resonance, dynamic tunability of the polarization conversion function from dual-broadband (0.45∼0.77 THz and 0.97∼1.2 THz) to ultra-broadband (0.38∼1.20 THz) can be realized with a high polarization conversion ratio. The scheme proposed here can find potential applications in integrated terahertz systems, sensing, imaging and communications areas.
Plasmonic nanodiscs on vanadium dioxide thin films for tunable luminescence enhancement
Authors: Cunningham Stephen , Hrelescu Calin , Bradley A. Louise
Published: June 2021

We propose an alternative method to dynamically tune luminescence enhancement in the near infrared spectral range using noble metal nanostructures on top of phase change material vanadium dioxide (VO2) thin films. The VO2 phase change is used to tune the nanodisc plasmon resonance providing a luminescence modification mechanism. We employ a model to calculate the emission of quantum emitters, such as dye molecules, in hybrid systems comprising single silver (Ag) nanodiscs on top of a thin layer of VO2. The model considers different dipole orientations and positions with respect to the nanostructure-VO2 film and determines the degree of observable luminescence modification. In the NIR spectral region, the observable photoluminescence of Alexa Dyes in the hybrid systems at room temperature is enhanced by more than a factor of 2.5 as compared to the same system without plasmonic particles. An additional photoluminescence enhancement by more than a factor of 2 can be achieved with the Ag nanodisc-VO2 film systems after the phase transition of the VO2. These systems can be used for tunable luminescence modification and for compensation of thermally induced luminescence quenching. Through optimization of the Ag nanodisc-VO2 film system, luminescence enhancements of up to a factor of 4 can be seen in the metallic VO2 compared to the semiconducting phase and would therefore compensate for a thermal quenching of up to 70% between room temperature and 70° C, rendering the hybrid systems as promising candidates for improved photon management in optoelectronic devices where elevated temperatures minimize the efficiencies of such devices.
High-sensitivity frequency modulation CARS with a compact and fast tunable fiber-based light source
Authors: Würthwein Thomas , Brinkmann Maximilian , Hellwig Tim , Wallmeier Kristin , Fallnich Carsten
Published: June 2021

Frequency modulation (FM) coherent anti-Stokes Raman scattering (CARS) is presented, using a compact as well as fast and widely tunable fiber-based light source. With this light source, Raman resonances between

700

c
m

−
1

and

3200

c
m

−
1

can be addressed via wavelength tuning within only 5 ms, which allows for FM CARS measurements with frame-to-frame wavelength switching. Moreover, the functionality for high-sensitivity FM CARS measurements was integrated by means of fiber optics to keep a stable and reliable operation. The light source accomplished FM CARS measurements with a 40 times enhanced sensitivity at a lock-in amplifier (LIA) bandwidth of 1 Hz. For fast imaging with frame-to-frame wavelength switching at a LIA bandwidth of 1 MHz, an 18-fold contrast enhancement could be verified, making this light source ideal for routine and out-of-lab FM CARS measurements for medical diagnostics or environmental sensing.
AlGaN-based deep ultraviolet micro-LED emitting at 275 nm
Authors: Yu Huabin , Memon Muhammad Hunain , Wang Danhao , Ren Zhongjie , Zhang Haochen , Huang Chen , Tian Meng , Sun Haiding , Long Shibing
Published: June 2021

The investigation of electrical and optical properties of micro-scale AlGaN deep ultraviolet (DUV) light-emitting diodes (LEDs) emitting at

∼

275

n
m

was carried out, with an emphasis on fabricated devices having a diameter of 300, 200, 100, 50, and 20 µm, respectively. It was revealed that the LED chips with smaller mesa areas deliver considerably higher light output power density; meanwhile, they can sustain a higher current density, which is mainly attributed to the enhanced current spreading uniformity in micro-scale chips. Importantly, when the diameter of LED chips decreases from 300 µm to 20 µm, the peak external quantum efficiency (EQE) increases by 20%, and the EQE peak current density can be boosted from

8.85

A

/

c
m

2

and

99.52

A

/

c
m

2

. Moreover, we observed a longer wavelength emission with enlarged full-width at half-maximum (FWHM) in the LEDs with smaller chip sizes because of the self-heating effect at high current injection. These experimental observations provide insights into the design and fabrication of high-efficiency micro-LEDs emitting in the DUV regime with different device geometries for various future applications.
Neuronal selectivity to complex vocalization features emerges in the superficial layers of primary auditory cortex
Authors: Montes-Lourido Pilar , Kar Manaswini , David Stephen V. , Sadagopan Srivatsun
Published: June 2021

Early in auditory processing, neural responses faithfully reflect acoustic input. At higher stages of auditory processing, however, neurons become selective for particular call types, eventually leading to specialized regions of cortex that preferentially process calls at the highest auditory processing stages. We previously proposed that an intermediate step in how nonselective responses are transformed into call-selective responses is the detection of informative call features. But how neural selectivity for informative call features emerges from nonselective inputs, whether feature selectivity gradually emerges over the processing hierarchy, and how stimulus information is represented in nonselective and feature-selective populations remain open question. In this study, using unanesthetized guinea pigs (GPs), a highly vocal and social rodent, as an animal model, we characterized the neural representation of calls in 3 auditory processing stages—the thalamus (ventral medial geniculate body (vMGB)), and thalamorecipient (L4) and superficial layers (L2/3) of primary auditory cortex (A1). We found that neurons in vMGB and A1 L4 did not exhibit call-selective responses and responded throughout the call durations. However, A1 L2/3 neurons showed high call selectivity with about a third of neurons responding to only 1 or 2 call types. These A1 L2/3 neurons only responded to restricted portions of calls suggesting that they were highly selective for call features. Receptive fields of these A1 L2/3 neurons showed complex spectrotemporal structures that could underlie their high call feature selectivity. Information theoretic analysis revealed that in A1 L4, stimulus information was distributed over the population and was spread out over the call durations. In contrast, in A1 L2/3, individual neurons showed brief bursts of high stimulus-specific information and conveyed high levels of information per spike. These data demonstrate that a transformation in the neural representation of calls occurs between A1 L4 and A1 L2/3, leading to the emergence of a feature-based representation of calls in A1 L2/3. Our data thus suggest that observed cortical specializations for call processing emerge in A1 and set the stage for further mechanistic studies.
Nuclear lipid droplets and nuclear damage in Caenorhabditis elegans
Authors: Mosquera Jose Verdezoto , Bacher Meghan C. , Priess James R.
Published: June 2021

Fat stored in the form of lipid droplets has long been considered a defining characteristic of cytoplasm. However, recent studies have shown that nuclear lipid droplets occur in multiple cells and tissues, including in human patients with fatty liver disease. The function(s) of stored fat in the nucleus has not been determined, and it is possible that nuclear fat is beneficial in some situations. Conversely, nuclear lipid droplets might instead be deleterious by disrupting nuclear organization or triggering aggregation of hydrophobic proteins. We show here that nuclear lipid droplets occur normally in C. elegans intestinal cells and germ cells, but appear to be associated with damage only in the intestine. Lipid droplets in intestinal nuclei can be associated with novel bundles of microfilaments (nuclear actin) and membrane tubules that might have roles in damage repair. To increase the normal, low frequency of nuclear lipid droplets in wild-type animals, we used a forward genetic screen to isolate mutants with abnormally large or abundant nuclear lipid droplets. Genetic analysis and cloning of three such mutants showed that the genes encode the lipid regulator SEIP-1/seipin, the inner nuclear membrane protein NEMP-1/Nemp1/TMEM194A, and a component of COPI vesicles called COPA-1/α-COP. We present several lines of evidence that the nuclear lipid droplet phenotype of copa-1 mutants results from a defect in retrieving mislocalized membrane proteins that normally reside in the endoplasmic reticulum. The seip-1 mutant causes most germ cells to have nuclear lipid droplets, the largest of which occupy more than a third of the nuclear volume. Nevertheless, the nuclear lipid droplets do not trigger apoptosis, and the germ cells differentiate into gametes that produce viable, healthy progeny. Thus, our results suggest that nuclear lipid droplets are detrimental to intestinal nuclei, but have no obvious deleterious effect on germ nuclei.
Temporal variations in reference evapotranspiration in the Tarim River basin, Central Asia
Authors: Wu Hao , Xu Min , Peng Zhuoyue , Chen Xiaoping
Published: June 2021

Reference evapotranspiration (ET0) is important for agricultural production and the hydrological cycle. Knowledge of ET0 can aid the appropriate allocation of irrigation water in arid regions. This study analyzed the trends in ET0 over different timescales in the Tarim River basin (TRB), Central Asia. ET0 was calculated by the Penman-Monteith method using data from 1960–2017 from 30 meteorological stations located in the TRB. The Mann-Kendall (MK) test with trend-free prewhitening and Sen’s slope estimator were applied to detect trends in ET0 variation. The results showed that the mean ET0 decreased at a rate of 0.49 mm·10 a-1 on an annual timescale. The mean ET0 exhibited a decreasing trend in summer and increasing trends in other seasons. The effects of climatic factors on ET0 were assessed by sensitivity analysis and contribution rate analysis. Maximum temperature (Tmax), relative humidity (RH) and wind speed (WS) showed important effects on ET0. However, WS, which decreased, was the key element that induced changes in ET0 in the TRB. This work provides an important baseline for the management of agricultural water resources and scientific planning in agriculture.
The relationship between the nomophobic levels of higher education students in Ghana and academic achievement
Authors: Essel Harry Barton , Vlachopoulos Dimitrios , Tachie-Menson Akosua
Published: June 2021

There is an upsurge in the use of mobile phones among higher education students in Ghana, which may result in the nomophobia prevalence with the students. Therefore, the need to assess the influence of nomophobia within the student population in Ghana. This descriptive cross-sectional study investigated the prevalence of nomophobia and the sociodemographic variables, and the association with academic achievement of the understudied population. A self-reporting nomophobia questionnaire, composed of 20 dimensions, was answered by 670 university students to measure the nomophobia prevalence. Raw data were estimated using descriptive statistics, and one-way ANOVA and Independent T-test. While the findings showed diverse grades of nomophobia, statistical significance between academic achievement and the level of nomophobia was observed. This study concludes that there is a high nomophobia prevalence among university students in Ghana as the use of smartphones increases. However, follow-up studies should be conducted in Ghanaian universities to monitor nomophobia and its associates in order to reduce the adverse effects of habitual use of smartphones.
Physicochemical and functional characterization of MYL-1501D, a proposed biosimilar to insulin glargine
Authors: Goyal Parag , Pai Harish Venkatraman , Kodali Phanichand , Vats Bhavesh , Vajpai Navratna , Annegowda Shankara , Mane Krishnappa , Mohan Shamini , Saxena Shruti , Veerabhadraia Anil Bangalore , Palande Milee , Nair Preethy Sasankan , More Digvijay Chandrashekar , Karudumpa Umamaheshwara Rao , Jyothirmai Kunala , Bhattacharya Adroha , Almeida Frida , Khyade Santosh Gulab , Gouda Shankara , Ranayhossaini Daniel J. , Moole Praveen Reddy , Smith Jeffrey P. , Barve Abhijit , Melarkode Ramakrishnan , Ullanat Rajesh
Published: June 2021

Insulin glargine is a long-acting analogue of human insulin that has been used to manage hyperglycemia in patients with diabetes mellitus (DM) for nearly 20 years. Insulin glargine has a relatively constant concentration-time profile that mimics basal levels of insulin and allows for once-daily administration. MYL-1501D is a biosimilar insulin glargine designed to offer greater access of insulin glargine to patients, with comparable efficacy and safety to the marketed reference product. We conducted a comprehensive panel of studies based on a formal analysis of critical quality attributes to characterize the structural and functional properties of MYL-1501D and reference insulin glargine products available in the United States and European Union. MYL-1501D was comprehensively shown to have high similarity to the reference products in terms of protein structure, metabolic activity (both in vitro cell-based assays and in vivo rabbit bioassays), and in vitro cell-based assays for mitogenic activity. The structural analyses demonstrated that the primary protein sequence was identical, and secondary and tertiary structures are similar between the proposed biosimilar and the reference products. Insulin receptor binding affinity and phosphorylation studies also established analytical similarity. MYL-1501D demonstrated high similarity in different metabolic assays of glucose uptake, adipogenesis activity, and inhibition of stimulated lipolysis. Rabbit bioassay studies showed MYL-1501D and EU-approved insulin glargine are highly similar to US-licensed insulin glargine. These product quality studies show high similarity between MYL-1501D and licensed or approved insulin glargine products and suggest the potential of MYL-1501D as an alternative cost-effective treatment option for patients and clinicians.
Functional analysis of CASK transcript variants expressed in human brain
Authors: Tibbe Debora , Pan Yingzhou Edward , Reißner Carsten , Harms Frederike L. , Kreienkamp Hans-Jürgen
Published: June 2021

The calcium-/calmodulin dependent serine protein kinase (CASK) belongs to the membrane-associated guanylate kinases (MAGUK) family of proteins. It fulfils several different cellular functions, ranging from acting as a scaffold protein to transcription control, as well as regulation of receptor sorting. CASK functions depend on the interaction with a variety of partners, for example neurexin, liprin-α, Tbr1 and SAP97. So far, it is uncertain how these seemingly unrelated interactions and resulting functions of CASK are regulated. Here, we show that alternative splicing of CASK can guide the binding affinity of CASK isoforms to distinct interaction partners. We report seven different variants of CASK expressed in the fetal human brain. Four out of these variants are not present in the NCBI GenBank database as known human variants. Functional analyses showed that alternative splicing affected the affinities of CASK variants for several of the tested interaction partners. Thus, we observed a clear correlation of the presence of one splice insert with poor binding of CASK to SAP97, supported by molecular modelling. The alternative splicing and distinct properties of CASK variants in terms of protein-protein interaction should be taken into consideration for future studies.
Early recognition of peripheral intravenous catheter failure using serial ultrasonographic assessments
Authors: Bahl Amit , Johnson Steven , Mielke Nicholas , Karabon Patrick
Published: June 2021

Objective

Peripheral intravenous catheter (PIVC) failure occurs frequently, but the underlying mechanisms of failure are poorly understood. We aim to identify ultrasonographic factors that predict impending PIVC failure prior to clinical exam.

Methods

We conducted a single site prospective observational investigation at an academic tertiary care center. Adult emergency department (ED) patients who underwent traditional PIVC placement in the ED and required admission with an anticipated hospital length of stay greater than 48 hours were included. Ongoing daily PIVC assessments included clinical and ultrasonographic evaluations. The primary objective was to identify ultrasonographic PIVC site findings associated with an increased risk of PIVC failure. The secondary outcome was to determine if ultrasonographic indicators of PIVC failure occurred earlier than clinical recognition of PIVC failure.

Results

In July and August of 2020, 62 PIVCs were enrolled. PIVC failure occurred in 24 (38.71%) participants. Multivariate logistic regression demonstrated that the presence of ultrasonographic subcutaneous edema [AOR 7.37 (1.91, 27.6) p = 0.0030] was associated with an increased likelihood of premature PIVC failure. Overall, 6 (9.67%) patients had subcutaneous edema present on clinical exam, while 35 (56.45%) had subcutaneous edema identified on ultrasound. Among patients with PIVC failure, average time to edema detectable on ultrasound was 46 hours and average time to clinical recognition of failure was 67 hours (P = < 0.0001).

Conclusions

Presence of subcutaneous edema on ultrasound is a strong predictor of PIVC failure. Subclinical subcutaneous edema occurs early and often in the course of the PIVC lifecycle with a predictive impact on PIVC failure that is inadequately captured on clinical examination of the PIVC site. The early timing of this ultrasonographic finding provides the clinician with key information to better anticipate the patient’s vascular access needs. Further research investigating interventions to enhance PIVC survival once sonographic subcutaneous edema is present is needed.
Decreased continuous sitting time increases heart rate variability in patients with cardiovascular risk factors
Authors: Nakayama Natsuki , Miyachi Masahiko , Tamakoshi Koji , Hayashi Toshio , Negi Koji , Watanabe Koji , Hirai Makoto
Published: June 2021

Aim

The purpose of the present study was to elucidate the relationship between high-frequency heart rate variability (HF HRV) and continuous daytime sitting time in patients with cardiovascular risk factors such as mild hypertension and/or stable angina pectoris.

Background

Decreased HF HRV precedes the progression and worsening of cardiovascular diseases. Continuous sitting behavior is a major risk factor for developing metabolic syndrome and is associated with cardiovascular disease, diabetes mellitus, renal failure, sarcopenia and osteoporosis. Risk factors for cardiovascular disease can be affected by continuous daytime sitting behaviors.

Design

The present study design was a post-hoc comparison.

Methods

Patients treated at two different primary care clinics from 2014 to 2018 were enrolled in this study (n = 53). We assessed HF HRV and continuous sitting time using 24-hour Holter electrocardiography and an activity meter at baseline and 6 months. HF HRV was calculated during sleep.

Results

Sitting time had decreased in 22 patients (decreased group) and increased in 31 patients (increased group) after 6 months. The mean patient ages were 73.1 and 72.0 years in the decreased and increased sitting time groups, respectively (p = 0.503). HF HRV during sleep had increased after 6 months in the decreased sitting time group. Compared with the increased group, the decreased group showed significantly higher HF HRV during sleep after 6 months by two-way repeated-measures ANOVA after adjustment for age, sex and change in activity (p = 0.045).

Conclusion

These results suggest that a decrease in sitting time might induce parasympathetic activity during sleep. Therefore, reducing continuous sitting time during the day might contribute, in part, to improving the prognosis of patients with cardiovascular risk factors not only by avoiding muscle loss but also by providing positive influences on parasympathetic tone during sleep.
Adolescents’ beliefs and perceptions of acne vulgaris: A cross-sectional study in Montenegrin schoolchildren
Authors: Ražnatović Đurović Milena , Janković Janko , Đurović Milica , Spirić Jelena , Janković Slavenka
Published: June 2021

Background

Acne is a common chronic inflammatory skin disease with a high prevalence in adolescent and early adult years. The aim of this study was to assess the self-perceived beliefs of Montenegrin secondary school pupils regarding the acne aggravating and ameliorating factors.

Methods

This cross-sectional survey of the pupils was conducted during October and November 2020 in four randomly selected public secondary schools in Podgorica, Montenegro. All 500 pupils were asked to fill in a questionnaire that included questions on age, sex, presence of acne, perceived acne aggravating and ameliorating factors, and sources of their information about acne.

Results

A total of 500 pupils, 234 (46.8%) boys, and 266 (53.2%) girls, aged 14−17 years, participated in the study. Acne was self-reported in 249 (49.8%) pupils, whereas 251 (50.2%) did not report acne. Factors most often believed to aggravate acne were inadequate face washing (85.0%), hormones (84.0%), sweets (82.0%), greasy food (72.6%), makeup (71.2%), and stress (67.8%). Overall the most prevalent acne ameliorating factors were cosmetic treatment (80.4%), increased water consumption (77.6%), a diet change to a healthier food choice (77.4%), and being on school holidays (62.2%). Girls reported more frequently that genetics, stress, sweets consumption, inadequate face wash, and makeup are acne exacerbating factors, whilst cosmetic treatment, increased water consumption, smoking, and being on school holidays are acne ameliorating factors. Boys more frequently considered the benefit of losing weight. There was no statistically significant difference between pupils with and without acne in perceived factors, except for cosmetic treatment. Those with acne more frequently believed in the benefits of cosmetic treatment.

Conclusions

Many adolescents’ self-perceived beliefs about factors that aggravate and ameliorate acne are myths and misconceptions without evidence-based justification. More efforts are needed to educate pupils about the acne aggravating and ameliorating factors, its health-related consequences, and the treatment possibilities.
Moluscos, crustáceos y equinodermos: restos de origen marino en los yacimientos prehistóricos
Authors: Álvarez Fernández Esteban
Published: June 2021

Se dan a conocer algunos de los resultados sobre las recientes investigaciones arqueozoológicas llevadas a cabo en diferentes yacimientos de la Región Cantábrica. Se presentan datos de diferentes restos marinos (moluscos, cangrejos, percebes, bellotas de mar y erizos) y se reflexiona sobre la información de diferente tipo que nos ofrecen (paleoeconómica, paleoclimática, etc.).
Problemática del estudio de yacimientos superficiales del Paleolítico Inferior y Medio, en la provincia de Ávila
Authors: Blanco Fernández María
Published: June 2021

La gran mayoría de los yacimientos pertenecientes al Paleolítico Inferior y Medio, en la Meseta Norte, proceden de depósitos al aire libre y carecen de una estratigrafía bien definida.A la hora de investigar la Prehistoria más antigua de zonas como la provincia de Ávila nos encontramos con una doble problemática: por un lado, las limitaciones que supone el estudio de este tipo de yacimientos por el nivel mínimo de información que presentan, ypor otro, la exclusividad de este tipo de evidencias líticas fuera de contexto estratigráfico como única fuente de inferencias.Sin embargo, los yacimientos en superficie pertenecientes al Paleolítico Inferior y Medio presentan un alto potencial informativo respecto a las pautas de comportamiento de los grupos humanos y de la utilización que estos hacen del espacio. Es por ello que no podemosrechazar esta fuente de datos cuando apenas tenemos ninguna otra. Del mismo modo, una correcta aplicación metodológica validará el análisis de dichas industrias.
Estudio del arte parietal paleolítico desde la perspectiva arqueológica: viejos fantasmas/ nuevos enfoques
Authors: Hernando Álvarez Clara
Published: June 2021

Esta comunicación pretende analizar los grafismos parietales paleolíticos desde la perspectiva arqueológica, dejando a un lado los vínculos estéticos de la historiografía tradicional. Se contrastarán las técnicas de análisis tradicional del arte paleolítico europeocon nuevas aplicaciones interdisciplinares, buscando un conocimiento arqueológico de las manifestaciones gráficas de las sociedades prehistóricas. Por último se propondrá un ensayo metodológico aplicando la Matriz Harris en la lectura y ordenación de los grafismos paleolíticos del panel central de la cueva de Llonín (Peñamellera Alta, Asturias).
Fuentes para el estudio de la romanización en la Meseta Norte
Authors: Pérez Martín Javier
Published: June 2021

La conquista romana del interior peninsular modificará las formas de vida en este territorio a todos los niveles, en un proceso que la historiografía ha dado en llamar romanización y que durará más de dos siglos. Dentro de este contexto histórico y geográfico, nos centraremos en la importancia de las distintas fuentes, exponiendo ejemplos significativos de cada una de ellas con los que señalaremos la abundante información que nos aportan, los distintos métodos de trabajo que usamos al manejarlas y algunas de las dificultadesque nos pueden surgir en su estudio. Todo ello con el objetivo de mostrar la necesidad del investigador en combinarlas y realizar un estudio detallado de las mismas, con el fin de conseguir una correcta interpretación del pasado.
Dos Crónicas Magrebíes Medievales: Al-Ḏajira Al-Saniyya y el Rawd al-Qirtas
Authors: Fernández Fonfría Lidia
Published: June 2021

En la presente comunicación pretendo exponer mis conclusiones referentes a un pequeño estudio comparativo entre dos de las más tempranas crónicas magrebíes que arrojan información sobre la tribu de los Banū Mar÷n y su llegada al trono magrebí en el siglo XIII. Gracias estas características comunes, permiten una visión más completa de una época que, sin duda, es la más desconocida del periodo benimerín, sus inicios. Las similitudes e influencia entre ambas son tales que existen diferentes teorías acerca de una posibleautoría común. Tras realizar el estudio y posterior análisis de dichas obras, se puede extraer que existen diferencias sustanciales a nivel estructural y estilístico que dificultan la posible identificación absoluta del autor de la Ḏajira al-Saniyya con el autor de RawÅ al-QirÐās.
Differential diagnosis of bovine intestinal diseases and their sequelae regarding ultrasonography and other diagnostic tools
Authors: Khalphallah Arafat , Elsayed Hanan K. , Elmeligy Enas , Bayomi Sara A. , Hamed Mohamed A. , Salman Doaa , Abu-Seida Ashraf M. , Mousa Sabry A.
Published: June 2021

Background and Aim: Intestinal disorders represented a large proportion of abdominal emergencies in bovine practice, and their definite diagnosis was a big challenge. The study described different intestinal disorders in cattle either in the small intestine (SI) or large intestine with their sequelae and peritonitis between SI loops. Materials and Methods: This study involved healthy (n=20) and diseased (n=40) cattle with intestinal disorders. All animals were undergoing clinical examination, laboratory analyses, and ultrasonographic examination. Results: Diseased cattle had monocytic leukocytosis as well as hypoproteinemia and hypoalbuminemia. The SI ileus of either proximal (n=12) or distal (n=15), intussusception (n=3), cecal, and/or colonal dilatation (n=10) were diagnosed by ultrasound and other diagnostic tools. Duodenum intussusception was imaged in cross-section as bull's eyes lesions. Animals with SI obstructions showed complete cessation (ileus with complete obstruction) or partial reduction of the peristaltic SI movement (ileus with partial obstruction), dilated duodenum (6.5-9.9 cm), and dilated jejunum and/or ileum (4.4-6.8 cm). Ultrasonography diagnosed SI ileus, due to either intestinal obstruction or peritonitis, and detected the ileus site, either proximal or distal. Cecal/colonal dilatation was detected using ultrasonography in which SI was not imaged and the peristaltic movements were completely reduced. The recorded intestinal disorders were associated with other disorders (e.g., liver cirrhosis or peritonitis). Conclusion: Ultrasonography played an important role in the differential diagnosis of intestinal disorders in cattle. Peritonitis between SI loops and cecal and/or colonal dilatation was also diagnosed.
Multi-Disciplinary Experience - A Key Learning Experience in Effective Education for Sustainable Development
Authors: Gooroochurn Mahendra , Toolsy Bhoomitra
Published: June 2021

The key role of education for achieving sustainable development has been well recognized around the world and used as a powerful lever for transforming economies based on sound principles. Indeed universities are prime institutions which have the essential role to impart requisite knowledge and skills to learners so that they can stand to the challenges in their respective professions, which means universities have had to bring radical changes to their curricula over the past decade to integrate sustainability principles as well as come up with new programmes centered on sustainability. However, the multi-disciplinary nature of sustainability projects as they occur in real-life has meant that the education curricula cannot be developed in isolation for a given programme of studies, but need to have linkages and crossover with other disciplines to provide a platform for learners to nurture this all-important skill. The University of Mauritius has aligned this key ingredient of education for sustainable development (ESD) with the accreditation framework for engineers provided by the Washington Accord through its graduate attributes, specifically Graduate Attribute 8 which includes multidisciplinary work within the range statement. This paper describes the methods adopted to implement this cross-linking between programmes from different disciplines effectively.
Prospect of Sustainability Course for Student’s Engagement in ESD
Authors: Ahmed Ferdous , Dastagir Muhammad Rehan , Rahman Mohammed Ataur , Nargis Selina
Published: June 2021

Educating and preparing young graduates with an actionoriented education program is the prime requirement for any country. Therefore, the Sustainability course is designed to develop resource persons to fulfill the immediate country’s demand for adequate ESD (Education for Sustainable Development) skilled graduates. Currently Bangladesh is thriving for Sustainable Development Goals (SDGs) by implementing the sustainability practices into the educational institutions. However, IUBAT is the pioneer for setting the sustainability course in undergraduate studies for any disciplines. Since today more than 10,000 undergrad students of the different disciplines have been taught the sustainability course where they engaged and practiced for any environmental degradation and resource conservation. Moreover, these students also spreading their sustainability knowledge and practices going to secondary and higher secondary school and colleges as a part of course assignments. Meanwhile IUBAT is a Green Campus, therefore students can practice for ESD with the appropriate green facilities. The aim of this paper is to disseminate the knowledge sharing that IUBAT leads introducing sustainability education at undergraduate level. This also highlights how IUBAT students are dedicated to participate and practicing for sustainable education for their lifelong learning which ultimately supports a nation’s dream of achieving SDGs by 2030.
ASSESSING CONGREGANTS PERCEPTION OF VULNERABILITY OF CHURCH BUILDINGS TO SECURITY THREATS IN NAIROBI COUNTY, KENYA
Authors: Baraza Hudson
Published: June 2021

This paper uses data collected for an MA Thesis on Assessing Congregants’ perception of Vulnerability of Church Buildings to security threats in Nairobi County, Kenya. The study has been necessitated by increased cases of targeted criminal attacks on congregants and church buildings in addition to increased perceptions of congregants as soft targets of insecurity, more pertinently in Nairobi County. The study will be guided by the following objectives; to investigate the nature of perceived vulnerability against church buildings; to explore congregant’s perceptions of what constitutes church buildings security and safety; to establish congregant’s perceptions of their level of preparedness in case of a criminal attack while in church buildings service; and to determine the congregant’s perceptions of what they think should be done to secure church buildings in Nairobi County Kenya. This study was grounded by two theories; Defensive Space Concept and Crime Prevention through Environmental Design (CPTED). This study adopted a cross-sectional survey design while Stratified random sampling technique was used to pick all the main respondents. Questionnaires were used to collect data from 182 members of each church (main respondents). In addition, Key Informants (K.I) guide was used to collect qualitative data from 8 K.I who include 4 Priests (1 from each church), and 4 security guards (one from each church). Data was analyzed with the aid of Statistical Package for Social Sciences (SPSS) and results presented using tables, bar and pie charts. The study results revealed that violent attacks against the churches in Nairobi county are on the increase (72%) and that the violent attacks against the churches in Nairobi county have inspired fear among church attendants (68.1%). Further, results showed the gun attacks were the most prevalent in church buildings (29.7%) closely followed by knife attacks (29.1%), explosive attacks (20.3%), suicide bombs (13.2%). Further, the results have revealed that some churches had employed various measures to counter violent attacks that included amongst other measures employed full time trained security staff to manage such incidents. Congregant’s perceptions on violent attacks against churches include; Knife and explosive attacks during services, but which have prompted fears of future gun or other terror attacks as is the case in other countries. According to the study; main measure of church security and safety included the Perimeter Walls, use of Surveillance cameras, use of Metal Detectors in church entrances, and heavy barriers in church entrance amongst other measures. As a policy measure, the study recommended formulation of standard security and safety measures applicable to all places of worship in Kenya that include; permanent security staff and armed security in all places of worship.
The Perception of Saudi Students toward Using Facilitation Strategies in Digital Classrooms
Authors: Althaqafi Abeer , Salami Faten Ahmed
Published: June 2021

Instructors use various strategies to facilitate learning and actively engage students in online courses. In this study, we examined students’ perception of the helpfulness of some different facilitation strategies used by instructors to establish instructors’ presence, instructors’ connection, engagement, and learning in online classrooms. 102 undergraduate students taking online courses due to COVID-19 pandemic at an English language institute at a Saudi university, responded to the web survey. Among the facilitation strategies, instructors being present in the discussion forum rated the highest in two constructs (instructors’ presence and students’ engagement). While video-based instructor introduction rated the highest for instructors’ connectedness. In addition, students found video-based course orientation was the most effective strategy to enhance online learning. Analysis of variance used to detect differences between gender, status, and age on all four constructs measured. No statistically significant differences were noticed for any one of the four latent constructs concerning discipline for the level of education and age. However, there was a significant difference between young and adult learners. Adult students had a stronger perception of using facilitation strategies to establish and enhance the four constructs than young students had.
The Effects of Domestic Violence on the Academic Performance of Pupils: A Case Study of Primary Schools in Laroo Division, Gulu Municipality
Authors: OKITE APIO SARAH
Published: June 2021

Study findings on the effects of domestic violence on academic performance have shown that individual academic performance levels are affected by a host of factors outside of the classroom including home environments. A cross-sectional study design was adopted where both qualitative and quantitative research approaches were used. Three schools out of 08 and a total of 42 respondents were sampled purposively or randomly to constitute study samples. Questionnaire and interview methods were used to collect primary and secondary data. Quantitative data were analyzed using SPSS V16 while content analysis was used for the qualitative data. A total of 50% of the respondents who are the majority said less concentration span is the effect of domestic violence on the school attendance.  The study reveals that majority of the pupils identified to be affected by domestic violence are isolated, depressed and violent as indicated by 58% which affects their class participation. 71% of the respondents said the school performance of pupils deteriorates. The study reveals that 60% of the respondents said poverty is the major cause of high drop out among pupils. It was concluded that high rate of poverty and drunkardness is the major cause of domestic violence and greatly affects the academic performance. It was recommended that the Government should pass ordnances on alcoholism as to reduce on the rate of domestic violence and improve academic performance of pupils from affected families.
Public Perception of the Effects of Poverty on Economic Growth in Ghana
Authors: Omoniyi Benjamin B. , Ogunwole O. O. , Owolabi S. O.
Published: June 2021

The paper examined public perception of the effects of poverty on economic growth in Ghana. It specifically examined public perception on the relationship between poverty and economic growth in Ghana using a combination of descriptive statistics and Logit Model to analyse the primary data collected. The result revealed that poverty does not lower investment, per capita income was not high enough to reflect Ghana’s resources, it was also discovered that poverty programmes are effective and standard of living were inadequate. The paper further discovered that unemployment rate was not too high in Ghana. Corruption does not pose any threat to poverty and economic growth. There existed low income inequality between the rich and the poor but income was not evenly distributed while  inflation does not increased the plight of the poor or deteriorates the living standard of the poor. The result further discovered that government performance was inadequate, lifespan was low, Ghana was able to meet MDGs goal by the end of 2015 but may not be able to sustain the achievement beyond 2015. Above all, poverty decisively slowed down the pace of economic growth in Ghana. The result of the Logit model showed that unemployment, corruption, secondary school enrollment, government policy, life-expectancy and poverty retarded economic growth while investment, aggregate consumption expenditure, pattern of income distribution and inflation, enhanced economic growth in Ghana. The result further revealed that only investment, aggregate consumption expenditure and inflation are the determinants of economic growth in Ghana. The paper concluded that poverty slowed down the pace of economic growth in Ghana. The paper therefore recommends that government should introduce and maintain policies that will permit improved relationships between poverty and other variables except investment, welfare and inflation so that they can positively and significantly contribute to increase economic growth in Ghana.
Die Proteste gegen die Corona-Maßnahmen
Authors: Frei Nadine , Schäfer Robert , Nachtwey Oliver
Published: June 2021

In den deutschsprachigen Gesellschaften sind bezüglich der Deutung einer pandemischen Lage und des richtigen Umgangs mit der Pandemie politische Konflikte entstanden. Das empirische Forschungsprojekt „Politische Soziologie der Corona-Proteste“ zeigt auf, dass es trotz motivationaler, inhaltlicher und weltanschaulicher Heterogenität dieser Protestbewegung eine zentrale verbindende Gemeinsamkeit gibt: Die Teilnehmer*innen und Sympathisant*innen der Proteste, die sich gegen die Corona-Maßnahmen richten, „vergemeinschaften“ sich über ein starkes Selbstverständnis als Kritiker*innen. In diesem Beitrag erfolgt eine Charakterisierung der „Coronakritiker*innen“ und Interpretationsvorschläge für eine soziologische Einordnung dieser Bewegung werden unterbreitet.