bluuebunny/crossref_metadata_2025 huggingface dataset:
Photoelectric Sensor Circuit and Image Segmentation Method for Radar System
Authors: Da Ting
Published: June 2021

In this exploration, based on the principle and system parameters of laser three-dimensional (3D) radar imaging technology, the corresponding photoelectric sensor circuit scheme is formulated. The sense circuit of avalanche photon diode (APD) converts the signal through the transresistance
amplifier circuit. Then, LMH6629 is selected as a precision amplifier with low input noise voltage and low input error current. The capacitance is used as a compensation element to compensate the phase. For the power supply scheme, choosing the mode of switching power supply and LDO to work
together can improve the efficiency of power supply and reduce the output of current ripple. At the same time, semantic segmentation is carried out for the obtained photoelectric images. Based on the traditional spatial pyramid pooling algorithm, the fusion of mean intersection over union
and cross information entropy loss function is introduced to improve the weight of local image region. In the experiment, Multisim software is used to simulate the circuit. The APD reverse bias voltage is set to 90 V, and the multiplication coefficient is 98.7. The feedback resistance, bandwidth,
phase compensation capacitance and other parameters are further calculated. It is found that there is obvious self-excited phenomenon in the output waveform of the transresistance amplifier without phase compensation capacitor. When the feedback capacitance reaches 0.8 pF, the oscillation
phenomenon is obviously reduced; further calculation shows that the bandwidth of transresistance amplifier is 230 MHz, and the noise of APD power supply is mainly caused by BUCK switching power supply switch when the bottom noise of oscilloscope is ignored. However, the noise is suppressed
under the action of the back-end LDO device; after the loss function is introduced, the contour of the photoelectric image is preserved completely, and then the more accurate segmentation results are obtained.
Design of Dynamic Random Access Memory Refresh Circuit Based on Temperature
Authors: Yin Wan-Jun , Ming Zheng-Feng , Wen Tao , Yuan Yi-Xue
Published: June 2021

This paper proposed a temperature adaptive refresh circuit for traditional memory with fixed refresh frequency, high refresh power consumption at low temperature and low refresh frequency at high temperature. The 2T core storage unit combining with the existing CMOS process and circuit
is taking as the research object, considering the characteristics of temperature rising, leakage current increasing, information holding time shortening, and the various constraints between the area, power consumption and other performance, this paper proposes to add the same redundant unit
as the storage array to the storage array as the temperature monitoring circuit to realize the adaptive refresh function, and designs the core circuit. The simulation results show that the design of SMIC 0.09 um standard CMOS process fully meets the requirements of memory adaptive refresh.
Sustainable Bio-Energy Production in Microbial Fuel Cell Using MnO2 Nanoparticle-Decorated Hollow Carbon Nanofibers as Active Cathode Materials
Authors: Parveen Nazish , Hiep Han Thi , Ali Ansari Sajid , Lee Moonyong
Published: June 2021

The widespread use of renewable energy remains a challenging and complex multidisciplinary problem. Developing alternatives using new technology such as nanotechnology is necessary to increase renewable energy’s scalability. Microbial fuel cells (MFCs) combined with nanotechnology
can improve bioelectricity generation during wastewater treatment. In this study, hollow carbon nanofibers (H-CNF) were decorated with manganese oxide (MnO2) via a simple chemical reduction method. MnO2-decorated H-CNF prepared with varying concentrations of manganese
precursor (MnO2@H-CNF) were characterized via different spectroscopic and microscopic techniques. The cathode catalyst performance of the MnO2@H-CNF was investigated in an //-type constructed MFC system using Shewanella Oneidensis MR1. The MnO2@H-CNF-1
in the assembled MFC displayed excellent power density of 25.7 mW/m2, which is higher than pure H-CNF (8.66 mW/m2), carbon cloth (5.10 mW/m2), and MnO2@H-CNF-3 (16 mW/m2). The maximum power generated in the MFC coupled with MnO2@H-CNF
as a cathode catalyst may have been due to the synergistic effect of the MnO2@H-CNF, which increased the electric conductivity and catalytic activity in the MFC’s cathode chamber. These results demonstrate that the developed MnO2@H-CNF cathode catalyst could improve
the MFC’s performance and reduce the operational costs of practical applications.
Facile Fabrication of Fluorine-Free Superhydrophobic Surfaces with SiO2 Monospheres
Authors: Liu Zhong-Peng , Song Si-Nan , Zhang Mu
Published: June 2021

Recently, superhydrophobic surface on various type of substrates have attracted much attentions in electronics field. In this work, the classic Stöber method was used to prepare spherical silica particles with different particle sizes by adding different amounts of electrolyte
(potassium chloride), giving rise to size distribution ranging from 300 nm to 2.55 yitm. Herein we constructed a micro-nano lotus-like structure in a facile way, achieving a superhydrophobic surface with using any Fluorine related chemicals. In the sense, the silica particles modified with
HMDS were sprayed to prepare hydrophobic surface with contact angle up to 152.96° by increasing the frequency of sprays.
Low Temperature VOx Hole Transport Layer for Enhancing the Performance of Carbon-Based Perovskite Solar Cells
Authors: Hu Ruiyuan , Li Yang , Que Zhongbao , Zhai Shuaibo , Feng Yifei , Chu Liang , Li Xing’ao
Published: June 2021

Carbon electrode based perovskite solar cells (PSCs) have attracted more attention owing to low product cost, long term stability and simple fabrication technology. Usually carbon electrode based PSCs are fabricated without hole transport layer, which results in slow development in
photovoltaic performance and practical application. In this work, we synthesized p-type semiconductor VOx films via low temperature solution process. And the prepared VOx film was introduced into the carbon electrode based PSCs as hole transport layer, which is highly beneficial to
further enhance the power conversion efficiencies. Here, we have demonstrated that solution processed VOx film is suitable to be the hole transport layer for PSCs based on low temperature carbon electrode. With the optimized layers of VOx, carbon electrode based PSCs with VOx exhibit enhanced
photovoltaic performance compared with hole transport layer free PSCs. In the meanwhile, carbon electrode based PSCs with VOx hole transport layer have long term stability.
Application of Photoelectric Sensor in Control of Industrial Robot
Authors: Zhang Yanjun , Liu Minqiang
Published: June 2021

Indoor positioning and automatic charging technology of the robot is an important indicator to test intelligent control of robot. The surrounding condition is collected by acousto-optic sensor and photoelectric sensor, and the closed-loop control of DC motor is realized based on Fuzzy
PID. The system integrates multiple photoelectric sensors and uses high-performance processor, S3C6410 ARM11, as the core instead of PC, reducing the power consumption and cost, so as to complete the acquisition of ranging information. And the environment image is obtained for image processing.
The infrared docking method is adopted in the docking process, that is, three infrared transmitting tubes in the charging dock emit different positions, and the position relative to the charging dock is judged according to the number of received signals. In the experiment, the positioning
error of industrial robot is about 1%, which can meet the requirements of indoor positioning. The docking success rate of automatic charging is more than 98%, and the time spent is less than 65 seconds, which satisfies with the requirements of automatic charging.
Drivers of Twenty-First Century U.S. Winter Precipitation Trends in CMIP6 Models: A Storyline-Based Approach
Authors: Schmidt Daniel F. , Grise Kevin M.
Published: June 2021

Climate change during the twenty-first century has the potential to substantially alter geographic patterns of precipitation. However, regional precipitation changes can be very difficult to project, and in some regions, global climate models do not even agree on the sign of the precipitation trend. Since some of this uncertainty is due to internal variability rather than model bias, models cannot be used to narrow the possibilities to a single outcome, but they can usefully quantify the range of plausible outcomes and identify the combination of dynamical drivers that would be likely to produce each.

This study uses a storylines approach—a type of regression-based analysis—to identify some of the key dynamical drivers that explain the variance in 21stcentury U.S. winter precipitation trends across CMIP6 models under the SSP3-7.0 emissions scenario. This analysis shows that the spread in precipitation trends is not primarily driven by differences in modeled climate sensitivity. Key drivers include global-mean surface temperature, but also tropical upper-troposphere temperature, the El Niño-Southern Oscillation (ENSO), the Pacific-North America (PNA) pattern, and the East Pacific (EP) dipole (a dipole pattern in geopotential heights over North America’s Pacific coast). Combinations of these drivers can reinforce or cancel to produce various high- or low-impact scenarios for winter precipitation trends in various regions of the United States. For example, the most extreme winter precipitation trends in the southwestern U.S. result from opposite trends in ENSO and EP, whereas the wettest winter precipitation trends in the midwestern U.S. result from a combination of strong global warming and a negative PNA trend.
Tropical origins of Weeks 2-4 forecasts errors during Northern Hemisphere cool season
Authors: Dias Juliana , Tulich Stefan N. , Gehne Maria , Kiladis George N.
Published: June 2021

A set of 30-day reforecast experiments, focused on the Northern Hemisphere (NH) cool season (November–March), is performed to quantify the remote impacts of tropical forecast errors on the National Centers for Environmental Prediction (NCEP) global forecast system (GFS). The approach is to nudge the model towards reanalyses in the tropics and then measure the change in skill at higher latitudes as function of lead time. In agreement with previous analogous studies, results show that midlatitude predictions tend to be improved in association with reducing tropical forecast errors during weeks 2-4, particularly over the North Pacific and western North America, where gains in subseasonal precipitation anomaly pattern correlations are substantial. It is also found that tropical nudging is more effective at improving NH subseasonal predictions in cases where skill is relatively low in the control reforecast, whereas it tends to improve less cases that are already relatively skillful. By testing various tropical nudging configurations, it is shown that tropical circulation errors play a primary role in the remote modulation of predictive skill. A time dependent analysis suggests a roughly one week lag between a decrease in tropical errors and an increase in NH predictive skill. A combined tropical nudging and conditional skill analysis indicates that improved Madden Julian Oscillation (MJO) predictions throughout its lifecycle could improve weeks 3-4 NH precipitation predictions.
Design of flexure revolute joint based on compliance and stiffness ellipsoids
Authors: Zhang Jing , Guo Hong-wei , Wu Juan , Kou Zi-ming , Eriksson Anders
Published: June 2021

In view of the problems of low accuracy, small rotational angle, and large impact caused by flexure joints during the deployment process, an integrated flexure revolute (FR) joint for folding mechanisms was designed. The design was based on the method of compliance and stiffness ellipsoids, using a compliant dyad building block as its flexible unit. Using the single-point synthesis method, the parameterized model of the flexible unit was established to achieve a reasonable allocation of flexibility in different directions. Based on the single-parameter error analysis, two error models were established to evaluate the designed flexure joint. The rotational stiffness, the translational stiffness, and the maximum rotational angle of the joints were analyzed by nonlinear finite element analyses. The rotational angle of one joint can reach 25.5° in one direction. The rotational angle of the series FR joint can achieve 50° in one direction. Experiments on single and series flexure joints were carried out to verify the correctness of the design and analysis of the flexure joint.
SpoVG is an important regulator of sporulation and affects biofilm formation by regulating Spo0A transcription in Bacillus cereus 0–9
Authors: Huang Qiubin , Zhang Zhen , Liu Qing , Liu Fengying , Liu Yupeng , Zhang Juanmei , Wang Gang
Published: June 2021

Background

Bacillus cereus0–9, a Gram-positive, endospore-forming bacterium isolated from healthy wheat roots in our previous research, is considered to be an effective biocontrol strain against several soil-borne plant diseases. SpoVG, a regulator that is broadly conserved among many Gram-positive bacteria, may help this organism coordinate environmental growth and virulence to survive. This study aimed to explore the multiple functions of SpoVG inB. cereus0–9.

Methods

The gene knockout strains were constructed by homologous recombination, and the sporulation process ofB. cereus0–9 and its mutants were observed by fluorescence staining method. We further determined the spore yields and biofilm formation abilities of test strains. Transcriptional fusion strains were constructed by overlapping PCR technique, and the promoter activity of the target gene was detected by measuring its fluorescence intensity.The biofilm production and colonial morphology ofB. cereus0–9 and its mutants were determined to study the functions of the target genes, and the transcription level of the target gene was determined by qRT-PCR.

Results

According to observation of the sporulation process ofB. cereus0–9 in germination medium, SpoVG is crucial for regulating sporulation stage V ofB. cereus0–9, which is identical to that ofBacillus subtilisbut differs from that ofBacillus anthracis. In addition, SpoVG could influence biofilm formation ofB. cereus0–9. The transcription levels of two genes closely related to biofilm-formation,sipWandcalY, were downregulated in a ΔspoVGmutant. The role of SpoVG in regulating biofilm formation was further explored by deleting the genesabrBandsinRin the ΔspoVGmutant, respectively, generating the double mutant strains ΔspoVGΔabrBand ΔspoVGΔsinR. The phenotypes of these double mutants were congruent with those of the singleabrBandsinRdeletion strains, respectively, which showed increased biofilm formation. This indicated thatspoVGwas located upstream ofabrBandsinRin the regulatory pathway ofB. cereusbiofilm formation. Further, the results of qRT-PCR and the luminescence intensity of transcriptional fusion strains indicated thatspoVGgene deletion could inhibit the transcription of Spo0A.

Conclusions

SpoVG, an important regulator in the sporulation ofB. cereus, is located upstream of Spo0A and participates in regulation of biofilm formation ofB. cereus0–9 through regulating the transcription level ofspo0A. Sporulation and biofilm formation are crucial mechanisms by which bacteria respond to adverse conditions. SpoVG is therefore an important regulator of Spo0A and is crucial for both sporulation and biofilm formation ofB. cereus0–9. This study provides a new insight into the regulatory mechanism of environmental adaptation in bacteria and a foundation for future studies on biofilm formation ofB. cereus.
SaQuant: a real-time PCR assay for quantitative assessment of Staphylococcus aureus
Authors: Wood Colin , Sahl Jason , Maltinsky Sara , Coyne Briana , Russakoff Benjamin , Yagüe David Panisello , Bowers Jolene , Pearson Talima
Published: June 2021

Background

Molecular assays are important tools for pathogen detection but need to be periodically re-evaluated with the discovery of additional genetic diversity that may cause assays to exclude target taxa or include non-target taxa. A single well-developed assay can find broad application across research, clinical, and industrial settings. Pathogen prevalence within a population is estimated using such assays and accurate results are critical for formulating effective public health policies and guiding future research. A variety of assays for the detection of Staphylococcus aureus are currently available. The utility of commercial assays for research is limited, given proprietary signatures and lack of transparent validation.

Results

In silico testing of existing peer-reviewed assays show that most suffer from a lack of sensitivity and specificity. We found no assays that were specifically designed and validated for quantitative use. Here we present a qPCR assay, SaQuant, for the detection and quantification of S. aureus as might be collected on sampling swabs. Sensitivity and specificity of the assay was 95.6 and 99.9 %, respectively, with a limit of detection of between 3 and 5 genome equivalents and a limit of quantification of 8.27 genome equivalents. The presence of DNA from non-target species likely to be found in a swab sample, did not impact qualitative or quantitative abilities of the assay.

Conclusions

This assay has the potential to serve as a valuable tool for the accurate detection and quantification of S. aureus collected from human body sites in order to better understand the dynamics of prevalence and transmission in community settings.
Investigation of long non-coding RNAs as regulatory players of grapevine response to powdery and downy mildew infection
Authors: Bhatia Garima , Upadhyay Santosh K. , Upadhyay Anuradha , Singh Kashmir
Published: June 2021

Background

Long non-coding RNAs (lncRNAs) are regulatory transcripts of length > 200 nt. Owing to the rapidly progressing RNA-sequencing technologies, lncRNAs are emerging as considerable nodes in the plant antifungal defense networks. Therefore, we investigated their role in Vitis vinifera (grapevine) in response to obligate biotrophic fungal phytopathogens, Erysiphe necator (powdery mildew, PM) and Plasmopara viticola (downy mildew, DM), which impose huge agro-economic burden on grape-growers worldwide.

Results

Using computational approach based on RNA-seq data, 71 PM- and 83 DM-responsive V. vinifera lncRNAs were identified and comprehensively examined for their putative functional roles in plant defense response. V. vinifera protein coding sequences (CDS) were also profiled based on expression levels, and 1037 PM-responsive and 670 DM-responsive CDS were identified. Next, co-expression analysis-based functional annotation revealed their association with gene ontology (GO) terms for ‘response to stress’, ‘response to biotic stimulus’, ‘immune system process’, etc. Further investigation based on analysis of domains, enzyme classification, pathways enrichment, transcription factors (TFs), interactions with microRNAs (miRNAs), and real-time quantitative PCR of lncRNAs and co-expressing CDS pairs suggested their involvement in modulation of basal and specific defense responses such as: Ca2+-dependent signaling, cell wall reinforcement, reactive oxygen species metabolism, pathogenesis related proteins accumulation, phytohormonal signal transduction, and secondary metabolism.

Conclusions

Overall, the identified lncRNAs provide insights into the underlying intricacy of grapevine transcriptional reprogramming/post-transcriptional regulation to delay or seize the living cell-dependent pathogen growth. Therefore, in addition to defense-responsive genes such as TFs, the identified lncRNAs can be further examined and leveraged to candidates for biotechnological improvement/breeding to enhance fungal stress resistance in this susceptible fruit crop of economic and nutritional importance.
Recurrent KRAS, KIT and SF3B1 mutations in melanoma of the female genital tract
Authors: Cai Yuan-jun , Ke Long-feng , Zhang Wen-wen , Lu Jian-ping , Chen Yan-ping
Published: June 2021

Background

Malignant melanoma of the female genital tract is relatively uncommon and accounts for 3–7% of all melanoma localizations. This study aimed to identify driver genes in melanoma of the female genital tract with the purpose of enhancing understanding of disease pathogenesis and identifying potential new therapeutic targets to develop effective therapies.

Methods

KIT (CD117) and BRAF expression were detected immunohistochemically. Polymerase Chain Reaction (PCR) and Sanger sequencing techniques were performed to identify the mutational status of BRAF, NRAS, KRAS, NF1, KIT, PDGFRA and SF3B1 on 19 melanomas of the female genital tract, paired with 25 cutaneous melanomas, 18 acral melanomas and 11 melanomas of nasal cavity.

Results

Somatic variant analysis identified KRAS (6/19; 32%) as the most commonly mutated gene, followed by KIT (4/19; 21%), SF3B1 (3/19; 16%) and NRAS (1/19; 5%). None of the cases were found to harbor BRAF, NF1 and PDGFRA mutations in melanomas of the female genital tract. However, none of the cases were found to harbor SF3B1 and KIT mutations in cutaneous melanomas, acral melanomas and melanomas of nasal cavity. Recurrent KIT mutations, as well as mutations in the less frequently mutated genes NRAS and SF3B1, were exclusively detected in vulvovaginal melanomas, but not in tumors arising in the cervix. However, recurrent KRAS mutations were detected in similar frequencies in tumors of the vulva, vagina, and cervix. Additionally, recurrent KRAS and KIT mutations occurred predominantly in polygonal and epithelioid cell types of melanoma in the female genital tract. Immunohistochemistry revealed moderate or strong cytoplasmic CD117 expression in 6 of the 19 cases (31.6%).

Conclusions

We observed that gynecologic melanoma harbored distinct mutation rates in the KIT, BRAF, SF3B1, KRAS, and NRAS genes. Our findings support the notion that gynecologic melanoma is a distinct entity from non-gynecologic melanoma, and these findings offer insights into future therapeutic options for these patients.
The determinants of 5th minute low Apgar score among newborns who delivered at public hospitals in Hawassa City, South Ethiopia
Authors: Yeshaneh Alex , Kassa Andargachew , Kassa Zemenu Yohannes , Adane Daniel , Fikadu Yohannes , Wassie Semahegn Tilahun , Alemu Biresaw Wassihun , Tadese Mesfin , Shitu Solomon , Abebe Haimanot
Published: June 2021

Background

Newborn morbidity and mortality are forecasted using the Apgar scores. Obstetricians worldwide have used the Apgar score for more than half a century for the assessment of immediate newborn conditions. It is a simple and convenient evaluation system that offers a standardized and effective assessment of newborn infants. Neonatal morbidity and mortality can be reduced if high-risk neonates are identified and managed adequately. This study aimed to assess the determinants of 5th minute low Apgar score among newborns at Public hospitals in Hawassa city, South Ethiopia.

Methods

A hospital-based unmatched case-control study was conducted at Public Hospitals in Hawassa city. Data were collected from 134 cases and 267 controls using a structured and pre-tested questionnaire by observing, interviewing, and reviewing patient cards. Newborns who delivered with a 5th minute Apgar score < 7 were considered as cases; whereas a similar group of newborns with a 5th minute Apgar score of ≥ 7 were categorized as controls. A consecutive sampling technique was employed to recruit cases, while a simple random sampling technique was used to select controls. Data entry and analysis were performed using Epi Data version 3.1 and SPSS version 20 respectively. Binary and multivariable analyses with a 95 % confidence level were performed. In the final model, variables withP < 0.05 were considered statistically significant.

Results

After controlling for possible confounding factors, the results showed that lack of physical and emotional support during labor and delivery [AOR = 3.5, 95 %CI:1.82–6.76], rural residence [AOR = 4, 95 %CI: 2.21–7.34], lack of antenatal care follow up [AOR = 3.5, 95 % CI: 1.91–6.33], anemia during pregnancy [AOR = 2.3,95 %CI: 1.10–4.71] and low birth weight [AOR = 6.2, 95 %CI: 2.78–14.03] were determinant factors of low Apgar scores. The area under the Apgar score ROC curve was 87.4 %.

Conclusions

Lack of physical and emotional support, rural residence, lack of ANC follow-up, low birth weight, and anemia during pregnancy were determinant factors of a low Apgar score. `Effective health education during preconception about anemia during pregnancy and ANC will help in detecting high-risk pregnancies that lead to a low Apgar score. In addition to the standard care of using electronic fetal monitoring, increasing access to compassion ships during labor and delivery is recommended.
Association of food insecurity with dietary patterns and expenditure on food, alcohol and tobacco amongst indigenous Inuit in Greenland: results from a population health survey
Authors: Bjerregaard Peter , Olesen Ingelise , Larsen Christina Viskum Lytken
Published: June 2021

Background

Amongst the indigenous Greenlandic Inuit, the experience of food insecurity has been attributed to a lack of money to buy enough food of sufficient quality to sustain a family, although a preference for alcohol and tobacco over food has also been cited. The purpose of the article was to compare dietary patterns and expenditure on food, alcoholic beverages and tobacco between survey participants who reported food insecurity and those who did not.

Methods

A countrywide cross-sectional health survey was carried out among 1886 adult Greenlandic Inuit in 2018. Diet was estimated by a food frequency questionnaire. Food insecurity status was based on the household hunger scale. Analyses were carried out by univariate general linear models adjusted for age, sex and social position.

Results

Nine percent of the participants reported food insecurity. Food insecurity was higher among younger participants, men and participants with low social position. Food insecure participants more often chose an unhealthy dietary pattern (43% vs. 32%) and they reported a higher energy intake. The food insecure spent the same amount of money on food as other participants but less on nutritious food and more on non-nutritious food. The cost per kilojoule (kJ) of the food of the food insecure was lower than that of the food secure (DKK 8.0 and 9.0 per 1000 kJ, respectively). The food insecure participants also spent considerably more on alcohol and tobacco.

Conclusions

The results suggest that it is not only unemployment and lack of money that creates food insecurity and unhealthy dietary patterns in Greenland. Food insecure participants gave higher priority to buying non-nutritious food, alcohol and tobacco than did food secure participants. There seems to be at least two population subgroups in Greenland with poverty and substance use, respectively, as the immediate determinants for food insecurity. The results are important for the design of interventions against food insecurity and unhealthy dietary patterns.
Identification of factors related to behaviors associated with musculoskeletal pain among elementary students
Authors: Rezapur-Shahkolai Forouzan , Gheysvandi Elham , Karimi-Shahanjarini Akram , Tapak Leili , Heidarimoghadam Rashid , Dianat Iman
Published: June 2021

Background

Musculoskeletal pains are among evident health problems in children and adolescents. Backpack carrying behaviors and the sitting postures are among behavioral factors associated with musculoskeletal pain in schoolchildren. Therefore, this study aims to identify the factors related to these important musculoskeletal behaviors, using Health Promotion Models.

Methods

In this cross-sectional study, a questionnaire was created based on PRECEDE Model and Health Belief Model and was administered to 673 Iranian students, whom were selected randomly from elementary schools of Hamadan, Iran, in 2018.

Results

The findings of the study revealed that proper sitting postures and backpack carrying were 42 and 33%, respectively. The findings also showed that predisposing factors including perceived susceptibility (p < 0.05, β = 0.219), perceived severity (p < 0.05, β = 0.166), perceived barriers (p < 0.05, β = − 0.191), perceived self-efficacy (p < 0.05, β = 0.188) and also enabling factors (p < 0.05, β = 0.329) were significantly related to sitting behaviors. Moreover, backpack carrying behaviors had significant relationships with predisposing factors of perceived susceptibility (p < 0.05, β = 0.198), perceived barriers (p < 0.05, β = − 0.258), perceived self-efficacy (p < 0.05, β = 0.185) and reinforcing factors (p < 0.05, β = 0.208).

Conclusions

It seems necessary for future preventive programs to take factors of musculoskeletal pains among children and adolescents into account.
Teaching scripts via smartphone app facilitate resident-led teaching of medical students
Authors: Zessis Nicholas R. , Dube Amanda R. , Sadanand Arhanti , Cole Jordan J. , Hrach Christine M. , Daud Yasmeen N.
Published: June 2021

Background

Previous studies have suggested that resident physicians are the most meaningful teachers during the clinical clerkships of third-year medical students (MS3s). Unfortunately, residents often feel unprepared for this crucial role. The pediatrics clerkship at our institution identified a paucity in the frequency of resident-led teaching with MS3s. Lack of confidence, suboptimal teaching space, and insufficient time were cited as the most significant barriers. To enhance resident-led teaching of MS3s, we created teaching scripts of general pediatrics topics accessible via a smartphone application (app).

Methods

Prior to the implementation of the app, MS3s and pediatric residents were surveyed on clerkship teaching practices. From May 2017 through July 2018, pediatric residents working with MS3s were introduced to the app, with both groups queried on resident teaching habits afterward. We compared pre-intervention and post-intervention data of time spent teaching, teaching frequency, and a ranking of pediatric resident teaching performance compared to residents of other MS3 core clerkships.

Results

44 out of 90 residents (49%) responded to a pre-intervention survey on baseline teaching habits. 49 out of 61 residents (80%) completed our post-intervention survey. Pre-intervention, 75% (33/44) of residents reported spending less than 5 min per teaching session on average. Post-intervention, 67% (33/49) reported spending more than 5 min (p < 0.01). 25% (11/44) of residents reported teaching at least once per day pre-intervention, versus 55% (27/49,p = 0.12) post-intervention. Post-intervention data demonstrated a statistically significant correlation between app use and increased frequency of teaching (p < 0.01). The MS3 average ranking of pediatric resident teaching increased from 2.4 to 3.4 out of 6 (p < 0.05) after this intervention.

Conclusions

Residency programs looking to reform resident-led teaching, particularly of residents early in their training, should consider our novel approach. In addition to addressing barriers to teaching and creating a platform for near-peer teaching, it is adaptable to any specialty or learner level. Future direction includes developing objective measures for teaching performance and content proficiency to better assess our intervention as an educational curriculum, as well as further investigation of the intervention as a controlled trial.
Heparin-binding protein in lower airway samples as a biomarker for pneumonia
Authors: Paulsson Magnus , Thelaus Louise , Riesbeck Kristian , Qvarfordt Ingemar , Smith Margaretha E. , Lindén Anders , Linder Adam
Published: June 2021

Objectives

Ventilator-associated pneumonia (VAP) is difficult to diagnose using clinical criteria and no biomarkers have yet been proved to be sufficiently accurate. The use of the neutrophil-derived Heparin-binding protein (HBP) as a biomarker for pneumonia was investigated in this exploratory case–control study in two intensive care units at a tertiary referral hospital.

Methods

Patients with clinical signs of pneumonia were recruited and bronchoalveolar lavage fluid (BALF) or bronchial wash (BW) samples were collected. Mechanically ventilated and lung healthy subjects were recruited as controls. HBP was measured with enzyme-linked immunosorbent assay.

Results

BALF was collected from 14 patients with pneumonia and 14 healthy controls. Median HBP in BALF pneumonia samples was 14,690 ng/ml and controls 16.2 ng/ml (p < 0.0001). BW was collected from 10 pneumonia patients and 10 mechanically ventilated controls. Median HBP in BW pneumonia was 9002 ng/ml and controls 7.6 ng/ml (p < 0.0001).

Conclusions

These data indicate that HBP concentrations is significantly higher in lower airway samples from patients with pneumonia than control subjects and is a potentially useful biomarker for diagnosis of VAP.
Gaps in evidence for the use of medically authorized cannabis: Ontario and Alberta, Canada
Authors: Lee Cerina , Round Jessica M. , Klarenbach Scott , Hanlon John G. , Hyshka Elaine , Dyck Jason R. B. , Eurich Dean T.
Published: June 2021

Background

With legal access to medical cannabis in Canada since 2001, there is a need to fully characterize its use at both the individual and population levels. We draw on data from Canada’s largest cohort study of medical cannabis to identify the primary reasons for medical cannabis authorization in Canada from 2014 to 2019 in two major provinces: Alberta (AB) and Ontario (ON), and review the extent that evidence supports each indication.

Methods

Self-reported baseline assessments were collected from adult patients in ON (n = 61,835) and AB (n = 3410) who were authorized medical cannabis. At baseline, sociodemographic, primary medical information, and validated clinical questionnaires were completed by patients as part of an individual assessment. Patients’ reasons for seeking medical cannabis were compared to published reviews and guidelines to assess the level of evidence supporting medical cannabis use for each condition.

Results

Medical cannabis use in both AB and ON was similar in both demographic and reason for authorization. The most common reasons for medical cannabis authorization were: (1) pain (AB = 77%, ON = 76%) primarily due to chronic musculoskeletal, arthritic, and neuropathic pain, (2) mental health concerns (AB = 32.9%, ON = 38.7%) due to anxiety and depression, and (3) sleep problems (AB = 28%, ON = 25%). More than 50 other conditions were identified as reasons for obtaining authorization.

Conclusion

In both AB and ON, the majority of reasons for medical cannabis authorization are not substantiated by clinical evidence to fully support its efficacy for long-term use. Ongoing epidemiological studies on medical cannabis on these treatments are warranted to fully outline its treatment benefits or risks.
Individual stiffness optimization of dorsal leaf spring ankle–foot orthoses in people with calf muscle weakness is superior to standard bodyweight-based recommendations
Authors: Waterval Niels F. J. , Brehm Merel-Anne , Harlaar Jaap , Nollet Frans
Published: June 2021

Background

In people with calf muscle weakness, the stiffness of dorsal leaf spring ankle–foot orthoses (DLS-AFO) needs to be individualized to maximize its effect on walking. Orthotic suppliers may recommend a certain stiffness based on body weight and activity level. However, it is unknown whether these recommendations are sufficient to yield the optimal stiffness for the individual. Therefore, we assessed whether the stiffness following the supplier’s recommendation of the Carbon Ankle7 (CA7) dorsal leaf matched the experimentally optimized AFO stiffness.

Methods

Thirty-four persons with calf muscle weakness were included and provided a new DLS-AFO of which the stiffness could be varied by changing the CA7® (Ottobock, Duderstadt, Germany) dorsal leaf. For five different stiffness levels, including the supplier recommended stiffness, gait biomechanics, walking energy cost and speed were assessed. Based on these measures, the individual experimentally optimal AFO stiffness was selected.

Results

In only 8 of 34 (23%) participants, the supplier recommended stiffness matched the experimentally optimized AFO stiffness, the latter being on average 1.2 ± 1.3 Nm/degree more flexible. The DLS-AFO with an experimentally optimized stiffness resulted in a significantly lower walking energy cost (− 0.21 ± 0.26 J/kg/m, p < 0.001) and a higher speed (+ 0.02 m/s, p = 0.003). Additionally, a larger ankle range of motion (+ 1.3 ± 0.3 degrees, p < 0.001) and higher ankle power (+ 0.16 ± 0.04 W/kg, p < 0.001) were found with the experimentally optimized stiffness compared to the supplier recommended stiffness.

Conclusions

In people with calf muscle weakness, current supplier’s recommendations for the CA7 stiffness level result in the provision of DLS-AFOs that are too stiff and only achieve 80% of the reduction in energy cost achieved with an individual optimized stiffness. It is recommended to experimentally optimize the CA7 stiffness in people with calf muscle weakness in order to maximize treatment outcomes.

Trial registration Nederlands Trial Register 5170. Registration date: May 7th 2015. http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=5170.
Detection of BCOR gene rearrangement in Ewing-like sarcoma: an important diagnostic tool
Authors: Li Lan , Zhang Ming , Chen Shaoyu , Sun Xiaoqi , Xu Hairong , Li Lina , Zhang Tingting , Huang Xiaoyuan , Ye Hongtao , Ding Yi
Published: June 2021

Background

BCOR-CCNB3 sarcoma (BCS) is a group of undifferentiated small round cell sarcomas harboring the BCOR gene rearrangement which shares morphology with the Ewing sarcoma family as well as other malignant round blue cell tumors, thus making them difficult to diagnose. The aim of this study was to explore the role of molecular techniques in the diagnosis of BCS.

Methods

Twenty-three cases of EWSR1 rearrangement-negative undifferentiated small round cell sarcomas (Ewing-like sarcoma) were analyzed for the presence of BCOR gene rearrangement by Fluorescence in situ hybridization (FISH) and Reverse Transcription -Polymerase Chain Reaction (RT-PCR). The clinicopathological features of the positive cases were also reviewed. Fifteen additional cases were used as negative controls.

Results

Eight cases were found with BCOR gene rearrangement by FISH and reappraised as BCS. The patients ranged in age from 8 to 20 years old, with a male predominance (M:F = 6:2). All tumors were located in the lower extremities. The tumor locations were more common in bone (n = 6) than deep soft tissue (n = 2). Histologically, 7 of 8 tumors were predominately composed of spindle or ovoid cells. The tumor cells were usually arranged in solid hypercellular sheets without a distinct architectural pattern. IHC showed expression of TLE1 (100%), CCNB3 (88%), BCOR (71%). RT-PCR for BCOR-CCNB3 fusion transcript was positive in 7 of 8 cases. Pre-operative chemotherapy resulted in eradication of tumors in 5 patients after a follow-up of 7 to 42 months.

Conclusions

Efficient diagnosis of BCOR rearranged sarcomas is achieved by the using a combination of FISH and RT-PCR assays.
Demographics, in-hospital analysis, and prevalence of 33 rare diseases with effective treatment in Shanghai
Authors: Cai Xiaoshu , Genchev Georgi Z. , He Ping , Lu Hui , Yu Guangjun
Published: June 2021

Background

Rare diseases are ailments which impose a heavy burden on individual patients and global society as a whole. The rare disease management landscape is not a smooth one—a rare disease is quite often hard to diagnose, treat, and investigate. In China, the country’s rapid economic rise and development has brought an increased focus on rare diseases. At present, there is a growing focus placed on the importance and public health priority of rare diseases and on improving awareness, definitions, and treatments.

Methods

In this work we utilized clinical data from the Shanghai HIE System to characterize the status of 33 rare diseases with effective treatment in Shanghai for the time period of 2013–2016.

Results and conclusion

First, we describe the total number of patients, year-to-year change in new patients with diagnosis in one of the target diseases and the distribution of gender and age for the top six (by patient number) diseases of the set of 33 rare diseases. Second, we describe the hospitalization burden in terms of in-hospital ratio, length of stay, and medical expenses during hospitalization. Finally, rare disease period prevalence is calculated for the rare diseases set.
Sirolimus in the treatment of kaposiform lymphangiomatosis
Authors: Zhou Jiangyuan , Yang Kaiying , Chen Siyuan , Ji Yi
Published: June 2021

Background

Kaposiform lymphangiomatosis (KLA), which is a new subtype of generalized lymphatic anomaly, is a rare disease with a poor prognosis. Currently, there is no standard treatment due to the poor understanding of KLA. Sirolimus, which is an inhibitor of mammalian target of rapamycin, has been shown to have promising potential in the treatment of complicated vascular anomalies. The aim of this study was to introduce the use of sirolimus for the treatment of KLA and to highlight the challenges of managing this refractory disease.

Results

We reported seven patients with KLA who received sirolimus therapy in our center. Combined with previously reported cases, 58.3% achieved a partial response, 25.0% had stable disease, and 16.7% experienced disease progression. No severe sirolimus-related adverse events occurred during treatment.

Conclusions

This study suggests that sirolimus is currently an option for the treatment of KLA, and it is hoped that more specific therapies will be developed in the future. Rapid advances in basic science and clinical practice may facilitate the development of important new treatments for KLA.
Delayed diagnosis of Peutz–Jeghers syndrome due to pathological information loss or mistake in family/personal history
Authors: Jiang Yu-Liang , Xu Xiao-Dong , Li Bai-Rong , Yu En-Da , Zhao Zi-Ye , Liu Hong
Published: June 2021

Objective

To report Peutz–Jeghers syndrome (PJS) cases with non-definitive clues in the family or personal history and finally diagnosed through pathological examination and STK11 gene mutation test.

Clinical presentation and intervention

PJS was suspected in 3 families with tortuous medical courses. Two of them had relatives departed due to polyposis or colon cancer without pathological results, and the other one had been diagnosed as hyperplastic polyposis before. Diagnosis of PJS was confirmed by endoscopy and repeated pathological examinations, and the STK11 mutation test finally confirmed the diagnosis at genetic level, during which 3 novel mutation were detected (536C > A, 373_374insA, 454_455insGGAGAAGCGTTTCCCAGTGTGCC).

Conclusion

Early diagnosis of PJS is important and may be based on a family history with selective features among family members, and the pathological information is the key. The novel mutations also expand the STK11 variant spectrum.
Computation offloading strategy based on deep reinforcement learning for connected and autonomous vehicle in vehicular edge computing
Authors: Lin Bing , Lin Kai , Lin Changhang , Lu Yu , Huang Ziqing , Chen Xinwei
Published: June 2021

Connected and Automated Vehicle (CAV) is a transformative technology that has great potential to improve urban traffic and driving safety. Electric Vehicle (EV) is becoming the key subject of next-generation CAVs by virtue of its advantages in energy saving. Due to the limited endurance and computing capacity of EVs, it is challenging to meet the surging demand for computing-intensive and delay-sensitive in-vehicle intelligent applications. Therefore, computation offloading has been employed to extend a single vehicle’s computing capacity. Although various offloading strategies have been proposed to achieve good computing performace in the Vehicular Edge Computing (VEC) environment, it remains challenging to jointly optimize the offloading failure rate and the total energy consumption of the offloading process. To address this challenge, in this paper, we establish a computation offloading model based on Markov Decision Process (MDP), taking into consideration task dependencies, vehicle mobility, and different computing resources for task offloading. We then design a computation offloading strategy based on deep reinforcement learning, and leverage the Deep Q-Network based on Simulated Annealing (SA-DQN) algorithm to optimize the joint objectives. Experimental results show that the proposed strategy effectively reduces the offloading failure rate and the total energy consumption for application offloading.
Body mass index, subjective body shape, and suicidal ideation among community-dwelling Korean adults
Authors: Yong Chae Eun , Kim Young Bum , Lyu Jiyoung
Published: June 2021

Background

Previous studies have not investigated in depth the combination of objective body weight and subjective body shape and its association with suicidal ideation among different age groups. Therefore, this study aimed to examine the abovementioned association among Korean adults, stratified by developmental stages.

Methods

We used nationally representative data from the 2017 Korean Community Health Survey, and included 222,037 participants aged 19 years or older in our study. Suicidal ideation was considered as the dependent variable (1 = yes, 0 = no). Along with body mass index (BMI) and subjective body shape measures, seven categories were created (1 = underweight-skinny, 2 = underweight-normal/fat, 3 = healthy weight-skinny, 4 = healthy weight-normal, 5 = healthy weight-fat, 6 = overweight-skinny/normal, 7 = overweight-fat). Multivariate logistic regression was conducted for each age group.

Results

Adjusted for covariates, young adults who were overweight-fat (OR = 1.18, p < .01), middle-aged adults who were underweight-skinny (OR = 1.32, p < .05), and older adults who were healthy weight-fat (OR = 1.19, p < .05) were more likely to have suicidal ideation than their healthy weight-normal counterparts.

Conclusions

The results suggest that the association between the combination of objective body weight and subjective body shape and suicidal ideation differs according to the developmental stage. Therefore, this difference should be considered when developing suicide prevention interventions based on the developmental stages.