bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Pyruvic Acid, Succinic Acid, and Oregano Essential Oil on Salmonella, Natural Microflora, and Quality of Raw Ground Chicken
Authors: Purohit A. , Harrison M. , Berrang M. , Singh R. , Mohan A.
Published: July 2021

ObjectivesThe growing stringency of regulations related to pathogens in raw poultry and increasing consumer demand for more natural food ingredients makes it imperative to explore alternative antimicrobial agents. The aim of this study was to assess the anti-Salmonella effect of combinations of succinate or pyruvic acid with oregano essential oil in raw ground chicken. Additionally, their effect on natural microflora and quality of ground chicken over simulated retail display was evaluated.Materials and MethodsNalidixic acid (NA) adapted Salmonella Typhimurium was inoculated on skin-on broiler breast meat pieces. The antimicrobial treatments given to meat were 2 and 3% pyruvic acid (PA) or monosodium succinate (SA) in combination with 0.5% essential oil (EO). Agar at the concentration of 0.05% was added to water used to prepare antimicrobial solutions to disperse the essential oil. Mode of antimicrobial treatment was 30 s dip. The meat was then ground and evaluated for pathogen reduction. Data were analyzed using 1-way ANOVA. Surviving Salmonella were recovered on XLT-4 with 50 ppm NA. Non-inoculated meat was similarly treated with antimicrobial dip and ground. Ground chicken was packaged in foam trays with PVC overwrap, and evaluated for mesophilic aerobic plate count (APC), psychrotrophic count (PC), pH, instrumental color (CIE L*, a*, and b*), and expressible moisture over 8 d of simulated retail display.A factorial design was assigned to the experiment with antimicrobial treatments and display days as the fixed effect factors. Data were analyzed using a mixed general linear model that considered replicates as a random effect in addition to the mentioned fixed effects. All trials were conducted in three replicates.ResultsMaximum reduction obtained in Salmonella counts from ground chicken was 1.52 log CFU/g and 0.98 log CFU/g, resulting from 3% SA + 0.5% EO, and 3% PA + 0.5% EO, respectively. Three percent SA + 0.5% EO treatment resulted in ground chicken with approximately 1.2 log CFU/g lower APC on Day 8 that was significantly lower (P < 0.05) than all other treatments. This treatment also resulted in less pH variation over the entire shelf life duration and lighter color of ground meat on Day 8.ConclusionThese results indicate that combination of monosodium succinate and oregano essential oil provides effective reduction of Salmonella and improved raw quality of ground chicken. This antimicrobial combination can be employed as a clean label ingredient for raw chicken applications.
Impacts of Chilling Duration on Marbling Score, Shrinkage, and Lean Color in Beef Carcasses
Authors: Haines Caitlyn , Sajeev Dishnu , Coatney Kalyn , Rivera Daniel , Dinh Thu
Published: July 2021

ObjectivesThis study was aimed to determine the effects of chilling duration on marbling score, shrinkage, and lean color of beef carcasses.Materials and MethodsTen beef carcasses of USDA Choice to Prime were selected at a commercial beef processing facility, randomly ribbed on either left or right side at 24 h, and evaluated repeatedly by a USDA grader at 24, 48, 72, and 96 h for quality grade, yield grade, and marbling score. Carcasses were hung in a cooler at 0 to 3°C, 3.1 m/s of wind speed, and 153 lux of fluorescent light. Ribeye temperature was recorded on both ribbed and un-ribbed sides of a carcass. Marbling score was converted to a numerical scale (200 = Practically Devoid00, 300 = Traces00, 400 = Slight00, 500 = Small00, 600 = Modest00, 700 = Moderate00, 800 = Slightly Abundant00, 900 = Moderately Abundant00, 1000 = Abundant00). Hot carcass weight and daily cold carcass weight were recorded to calculate shrinkage. Lean color (L*, a*, and b*), surface reflectance spectra (400 to 700 nm), and pH were recorded only at 72 and 96 h. Surface deoxymyoglobin, oxymyoglobin, and metmyoglobin percentages were calculated using the reflectance spectra according to AMSA guidelines. Statistical analysis was performed by the GLIMMIX and the PANEL procedures of SAS 9.4 (SAS Institute Inc., Cary, NC). Actual probability values were reported.ResultsAt 24 h, in both ribbed and un-ribbed sides, ribeye temperature reached 2.7 to 3.3°C after 24-h chilling and all carcasses were graded with marbling score ranging from 620 to 800 (mean = 710; standard deviation = 73). Compared with 24 h, marbling score did not change at 48 h (P = 0.443) but was increased by 10 points at 72 h (P = 0.023) and by 21 points at 96 h (P = 0.014). Carcass weight was increased by 0.6% by 48 h, 1.1% by 72 h, and 0.4% by 96 h (P ≤ 0.007) compared with 24 h; however, such an increase was caused by a malfunction of the spray-chill system, which continuously sprayed the carcasses for 96 h instead of intermittently for 24 h. The L* value (lightness) was increased from 40.2 to 43.4 (P = 0.014) and so were surface metmyoglobin and deoxymyoglobin by 1% from 72 to 96 h (P = 0.035 and 0.0121, respectively); however, such a small increase has no biological significance. The pH value remained constant at 5.6 from 72 to 96 h. The regression analysis by the PANEL procedure indicated that the marbling score in this dataset could be predicted by chilling time, as follow: marbling score = 740 + 0.3 × time (h) (R2 = 0.98; P < 0.001 for both the intercept and slope).ConclusionThe findings suggest that 96-h chilling increases marbling score of beef carcasses and such an increase (20 points) can potentially allow the carcasses borderline on a higher grade to be graded higher without negatively affecting shrinkage, lean color, and pH.
A Proposed Mechanism for Texture Property of Woody Breast in Broilers
Authors: Welter A. , Wu W. J. , O’Quinn T. , Houser T. , Boyle E. , Chao M. , Boyle D. , Bowker B. , Zhuang H.
Published: July 2021

ObjectivesWoody breast is a myopathy observed in chicken breast meat (Pectoralis major) characterized by its tough and rubbery texture. However, the exact causation of woody breast texture is still unknown. We hypothesize that sarcoplasmic reticulum (SR) dysfunctionality early postmortem results in rapid leakage of intracellular calcium may partially contribute to the abnormal meat texture observed in woody breast meat. The objective of this preliminary study was to investigate this hypothesis.Materials and MethodsFourteen Ross line broiler breast fillets (7 severe woody breast and 7 normal) were collected at 3 h postmortem from a commercial processing plant located in the southeast United States. The 7 woody breast samples also exhibited moderate to severe white striping. The 7 normal samples did not exhibit any signs of white striping or woody breast. Each sample was trimmed, weighed, vacuum packaged and frozen at –20°C at approximately 8 h postmortem. One 1.9 cm strip across the cranial end of each fillet was fabricated and pulverized in liquid nitrogen to measure sarcomere length (Laser Scan Confocal Microscope with a 100x/NA 1.4 objective), calpain activity (immunoblotting for µ-calpain autolysis), proteolysis (immunoblotting for troponin-T degradation) and collagen content (hydroxyproline content). Purge was also collected from each sample to evaluate protein (bicinchoninic acid assay) and free calcium concentration (atomic absorption).ResultsWoody breast fillets were heavier than normal chicken breast fillets (522.9 vs. 446.9g; P < 0.05). Woody breast samples tended to have shorter sarcomeres (1.70 vs. 2.02 µm; P = 0.0543) and less intact troponin-T compared to normal breast samples (relative intact troponin-T band density: 49.98 vs. 56.97%; P = 0.0515) at 8 h postmortem. It was interesting to note that no µ-calpain band was detected through immunoblotting for both the woody breast and normal samples at 8 h postmortem. Other studies have found similar results as poultry µ-calpain autolyzed at a much rapid rate than µ-calpain in mammalian species. In addition, the purge from woody breast samples also had higher levels of free calcium compared to normal samples (6.2 vs. 4.2 nmol calcium/mg protein; P < 0.05). Lastly, there was more collagen present in the woody breast samples compared to normal chicken breast samples (3.89 vs. 2.08 mg collagen/g muscle tissue; P < 0.05).ConclusionThe results indicated that the cause of texture abnormality of woody breast may be the combined effects of more calcium being released from the SR early postmortem resulting in shorter sarcomere length and more collagen being deposited in the chicken breast meat. Additional research with the focus on SR integrity and functionality as well as collagen crosslinks are needed to further elucidate the basic mechanism of woody breast texture formation.
Evaluation of Beef Cattle Temperament Attributes Using Infrared Thermography Technology
Authors: Ogdahl W. P. , Young J. , Frandrup J. , Hanna L. L. Hulsman , Sun X.
Published: July 2021

ObjectivesThe objective of this study was to evaluate beef cattle temperament scores using infrared thermography technology.Materials and MethodsAngus and Angus × Hereford calves (total n = 650) were brought through a handling chute system over two weaning sessions (October 2016 and 2017). Beef cattle temperament was subjectively quantified by (1) temperament score (TS), the disposition of the animal observed by an individual evaluator on a scale of 1 (calm) to 5 (excitable); (2) docility score (DS), the level of observed calmness of the animal displayed (1 = calm to 6 = excitable); and (3) qualitative behavior assessment (QBA), scored on twelve different attributes, (i.e., active, relaxed, etc.). There were two traits measured on a four-platform standing scale: (1) the standard deviation of total weight over time (SSD); and (2) the SSD’s coefficient of variation (CVSSD). Thermal images of the animal’s head were acquired by industrial fixed focus infrared camera (TiS40, Fluke Corporation, Everett, WA). The maximum, minimum, average, and standard deviation of temperature of the eye region were extracted from the thermal images. Stepwise and linear regression analyses to estimate subjective temperament traits from thermal imaging data and scale data were conducted using the reg procedure in SAS (v. 9.4, SAS Institute, Inc., Cary, NC). Correlations were estimated using the corr procedure in SAS.ResultsThe results showed low correlations between thermal imaging and subjective temperament traits. The correlations that were significant were around an absolute value of 0.1. However, all four thermal imaging traits were significantly correlated when the animal exhibited distress observed by QBA. When fitting only thermal imaging data into the regression analyses, R2 values were all under 0.03. When including SSD and CVSSD, there were a few traits with an R2 > 0.1 and none having an R2 > 0.15. The QBA traits that had an R2 between 0.1 and 0.15 were active, fearful, calm, apathetic, happy, and distressed for both linear and stepwise regressions.ConclusionAdditional validation research on this thermal imaging technology needs to be conducted with temperamental cattle as this current data was collected using observed calmer cattle, to give a more realistic application to beef cattle production. Overall this result shows potential to achieve beef cattle temperament evaluation with thermal imaging.Figure 1.
Effect of Temperature on Oxymyoglobin and Metmyoglobin Denaturation Properties
Authors: Belem T. S. , Chaudhary B. , Mohanty S. , Mafi G. , VanOverbeke D. , Ramanathan R.
Published: July 2021

ObjectivesPremature browning is a condition where the interior of patty/steak will appears fully cooked before the temperature necessary to kill foodborne pathogens is reached. Previous research reported that approximately 50% of ground beef retailed in the US is susceptible to premature browning. Myoglobin form present in the interior of steak or patties determines the cooked color appearance. Although previous studies noted that myoglobin denaturation is primarily responsible for the cooked color appearance, limited knowledge is currently available about the effect of temperature on oxymyoglobin and metmyoglobin denaturation properties. The objective of the current study was to determine the effects of myoglobin forms on thermal stability using circular dichroism spectroscopy.Materials and MethodsOxymyoglobin and metmyoglobin solutions at pH 5.6 in 50 mM sodium phosphate buffer were incubated in a continuous heat increment water bath for 10 min. At specific temperature points (65, 71, 73, and 76°C), myoglobin denaturation was determined by changes in myoglobin concentration and by protein unfolding (fluorescence and absorbance) methods. The myoglobin thermal stability was also determined by circular dichroism spectroscopy. Changes in secondary protein structure were determined every 2°C from 52 to 92°C. The data were analyzed as completely randomized using the Mixed Procedure of SAS. A significance level of 0.05 was used to determine differences between means.ResultsOxymyoglobin had greater (p < 0.05) unfolding (as indicated by absorbance changes) than metmyoglobin at all temperatures. However, at 65, 71, and 73°C there were no differences (p > 0.05) in fluorescence intensities between myoglobin forms. Circular dichroism spectroscopy indicates that oxymyoglobin is more heat labile than metmyoglobin.ConclusionThe results indicate that oxymyoglobin had greater denaturation and unfolding than metmyoglobin. Use of appropriate myoglobin denaturation quantification technique will help characterize premature browning.
Enforcement of the Non-Retroactive Principle in the Bali Bombing Case I in the Constitutional Court of Indonesia Decision Number 013 / PUU-I / 2003
Authors: Suta I Made Gemet Dananjaya , Prabandari I Gusti Agung Mas , Saraswati Ida Ayu Agung
Published: July 2021

Penerapan asas retroaktif pada kasus bom Bali I berdasarkan Undang-Undang Nomor 16 Tahun 2003 dimaksudkan untuk memberikan rasa keadilan kepada masyarakat, namun uji materil atas penerapan norma retroaktif tersebut dinilai inkonstitusional oleh Mahkamah Konstitusi melalui keputusan nomor 013/PUU-I/2003. Pro dan kontra dari putusan tersebut terjadi di masyarakat, antara menegakkan kepastian hukum atau memenuhi rasa keadilan bagi para korban. Tulisan ini berupaya mengkaji putusan Mahkamah Konstitusi No. 013/UU-I/2003 dengan memaparkan pertimbangan hukum MK dalam memutus perkara tersebut. Metode penelitian yang digunakan dalam penelitian ini adalah metode penelitian hukum normatif dengan menggunakan pendekatan perundang-undangan dan pendekatan konseptual. Tulisan ini menyimpulkan bahwa asas nonretroaktif merupakan asas yang mutlak harus ditegakkan karena merupakan salah satu asas yang menjamin perlindungan hak asasi manusia yang tidak dapat dikurangi dalam keadaan apapun.
Spacetime Quantum Reference Frames and superpositions of proper times
Authors: Giacomini Flaminia
Published: July 2021

In general relativity, the description of spacetime relies on idealised rods and clocks, which identify a reference frame. In any concrete scenario, reference frames are associated to physical systems, which are ultimately quantum in nature. A relativistic description of the laws of physics hence needs to take into account such quantum reference frames (QRFs), through which spacetime can be given an operational meaning. Here, we introduce the notion of a spacetime quantum reference frame, associated to a quantum particle in spacetime. Such formulation has the advantage of treating space and time on equal footing, and of allowing us to describe the dynamical evolution of a set of quantum systems from the perspective of another quantum system, where the parameter in which the rest of the physical systems evolves coincides with the proper time of the particle taken as the QRF. Crucially, the proper times in two different QRFs are not related by a standard transformation, but they might be in a quantum superposition one with respect to the other.Concretely, we consider a system of N relativistic quantum particles in a weak gravitational field, and introduce a timeless formulation in which the global state of the N particles appears "frozen", but the dynamical evolution is recovered in terms of relational quantities. The position and momentum Hilbert space of the particles is used to fix the QRF via a transformation to the local frame of the particle such that the metric is locally inertial at the origin of the QRF. The internal Hilbert space corresponds to the clock space, which keeps the proper time in the local frame of the particle. Thanks to this fully relational construction we show how the remaining particles evolve dynamically in the relational variables from the perspective of the QRF. The construction proposed here includes the Page-Wootters mechanism for non interacting clocks when the external degrees of freedom are neglected. Finally, we find that a quantum superposition of gravitational redshifts and a quantum superposition of special-relativistic time dilations can be observed in the QRF.
Public Procurement Transparency and Openness Effective Instruments Analysis
Authors:   Russian Presidential Academy of National Economy and Public Administration, Bondareva E.A.
Published: July 2021

Liability measures provided by the legislation and reports of the controlling bodies are analyzed. The conclusion is drawn that it is necessary to strengthen administrative and criminal liability for violations of the law in the course of public procurement. The author proposes tools to ensure compliance with the principles of transparency and openness of public procurement.
“Political” and “Religious” Labels in Social Media as a Tool for Political Mobilization
Authors:   Pskov State University, Makovsky A.A. , Dmitriev S.S. ,   Pskov Region Administration Apparatus
Published: July 2021

Ways and methods of digital mobilization of citizens through forming political labels for protest actions are considered. The most popular social media in the Russian Federation are analyzed in terms of forming political labels, as well as the tone of information and the mechanisms for mobilizing citizens. The authors come to the conclusion that most commonly in practice a political label is a trivial linguistic sign that establishes a negative, discriminatory connection between a signifier and a political phenomenon.
The effects of hypocaloric, high-protein diets on cardiovascular risk factors and weight loss in metabolically healthy obese adults: a systematic review
Authors: Lauran Martin , Hosseini Mostafa , Ali Kosar Mohamed
Published: July 2021

Background: This systematic review has been undertaken in order to
assess the effects of hypocaloric, high-protein diets on weight loss and
cardiovascular risk factors such as serum lipid levels in metabolically
healthy obese adults. The primary outcomes measured include changes in
pre- and post- diet mean BMI, LDL-C, HDL-C, TAG, and TC levels. Method:
Four databases including: Embase, MEDLINE (via PubMed), Cochrane and Web
of Science were searched with no restrictions on language or publication
period. Clinicaltrials.gov was also searched in order to identify
unpublished or on-going studies. Results: Three of four studies included
in this systematic review noted a significantly greater loss in pre- and
post- diet mean BMI levels in the hypocaloric, high-protein diet group
as compared to hypocaloric, non-high protein diets (control). Whilst
pre- and post-diet mean LDL-C, HDL-C, TAG, and TC levels did not differ
significantly among hypocaloric, high-protein and control diet groups.
Conclusion: Hypocaloric, high-protein diets had an unclear effect on
blood-lipid levels as compared to control. Weight loss however was
significantly greater in the hypocaloric, high-protein group as compared
to other hypocaloric, non-high-protein diet groups.
Pushing the Limits of Luminescence Thermometry: Probing the Temperature of Proteins in Cells
Authors: Maciel Glauco
Published: July 2021

Proteins are involved in numerous cellular activities such as transport
and catalysis. Misfolding during biosynthesis and malfunctioning as a
molecular machine may lead to physiological disorders and metabolic
problems. Protein folding and mechanical work may be viewed as
thermodynamic energetically favorable processes in which stochastic
nonequilibrium intermediate states may be present with conditions such
as thermal fluctuations. In my opinion, measuring those thermal
fluctuations may be a way to access the energy exchange between the
protein and the physiological environment and to better understand how
those nonequilibrium states may influence the misfolding/folding process
and the efficiency of the molecular engine cycle. Here, I discuss
luminescence thermometry as a possible way to measure those temperature
fluctuations from a single molecule experimental perspective with its
current technical limitations and challenges.
Prediction and characterization of the T cell epitopes for the major soybean protein allergens using bioinformatics approaches
Authors: Zhou Fanlin , He Shudong , Wang Yongfei , Sun Hanju , Zhang Yi
Published: July 2021

Protein allergens is a health risk for consumption of soybeans. To
understand allerginicity mechanism, T cell epitopes of 7 soybean
allergens were predicted and screened by abilities to induce cytokine
interleukin 4. The relationships among amino acid composition,
properties, allergenicity and pepsin hydrolysis sites were analyzed.
Among the 138 T cell epitopes identified, YIKDVFRVIPSEVLS,
KDVFRVIPSEVLSNS, DVFRVIPSEVLSNSY of Gly m 6.0501 (P04347), and
AKADALFKAIEAYLL, ADALFKAIEAYLLAH of Gly m 4.0101 (P26987) were the most
possible epitope candidates. In T cell epitopes pattern, the frequencies
of amino acids Q, D, E, P and G decreased, while F, I, N, V, K and H
increased. Hydrophobic residues at positions p1 and p2 and positively
charged residues in positions p13 might contribute to allergenicity.
Most of epitopes could be hydrolyzed by pepsin into small polypeptides
within 12 residues length, and the anti-digestive epitope regions
contained I, V, S, N, and Q residues. T cell epitopes EEQRQQEGVIVELSK
from Gly m 5.03 (P25974) showed resistantence to pepsin hydrolysis and
would cause a higher Th2 cell response. This research provides basis for
the development of hypoallergenic soybean products in the soybean
industry as well as for the immunotherapy design for protein allergy.
Utility of contrast-enhanced echocardiography in the diagnosis and follow-up of a pseudoaneurysm of the aortic arch
Authors: Wu Yu , Li Yuman , Xu Jia , Menghe Wang , Lv Qing
Published: July 2021

Spontaneous pseudoaneurysm of the aortic arch is an exceptionally rare
and potentially life-threatening condition.Diagnosis of pseudoaneurysms
of the aortic arch mainly depends on imaging
examinations.Contrast-enhanced echocardiography, as a non-invasive,
bed-side and radiation-free tool, plays an important role in the rapid
diagnosis and postoperative follow-up of pseudoaneurysms of the aortic
arch.
Molecular characterization of a large cohort of Mucopolysaccharidosis patients: Iran Mucopolysaccharidosis RE-diagnosis Study (IMPRESsion)
Authors: Ghaffari Saeed , Rafati Maryam , Shadnoush Mahdi , Pourbabaee Shokooh , Aghighi Mohammad , Samiee Siamak Mirab , Kermanchi Jamshid , Alaei Mohammad Reza , Salehpoor Shadab , Amirkashani Davoud , Sotoodeh Aria , Sarkhail Peymaneh , Badv Reza Shervin , Aminzadeh Majid , Shiva Siamak , Eshraghi Peyman , Moravej Hossein , Hashemipour Mahin , Rostampour Noushin , Hamidieh Amir Ali , Shamsian Bibi Shahin , Shams Sedigheh , Zamanfar Daniel , Ebrahimi Ayoub , Otadi Ali , Tara Seyedeh Zahra , Barati Zeinab , Fakhri Laya , Hosseini Azadeh , Amiri Hosna , Ramandi Somayeh , Mostofinezhad Niusha , Kani Zahra Pahlevani , Mohammadyari Elham , Khosravi Mahsa , Saadati Masoome , Hoseininasab Fatemeh , Khorshid Hamid Reza Khorram , Modaberisaber Younes
Published: July 2021

Mucopolysaccharidoses (MPSs) are rare, heterogeneous inborn errors of
metabolism (IEM) diagnosed through a combination of clinical,
biochemical, and genetic investigations. The aim of this study was
molecular characterization of the largest cohort of Iranian MPS patients
(302 patients from 289 unrelated families), along with tracking their
ethnicity and geographical origins. 185/289 patients were studied using
an IEM-targeted NGS panel followed by complementary Sanger sequencing,
which led to the diagnosis of 154 MPS patients and 5 non-MPS IEMs
(diagnostic yield: 85.9%). Furthermore, 106/289 patients who were
referred with positive findings went through re-analysis and
confirmatory tests which confirmed MPS diagnosis in 104. Among the total
of 258 MPS patients, 225 were homozygous, and 9 had copy number
variations, and 90 had novel variants. MPS IV was the most common type
(34.8%) followed by MPS I (22.7%) and MPS VI (22.5%). Geographical
origin analysis unveiled a pattern of distribution for frequent variants
in ARSB (c.430G>A, c.962C>T,
c.281C>A), GALNS (c.319G>A,
c.860C>T, c.1042A>G), and IDUA
(c.1A>C, c.1598C>G). Our extensive patient
cohort reveals the genetic and geographic landscape of MPS in Iran,
which provides insight into the genetic epidemiology of MPS and can
facilitate a more cost-effective, time-efficient diagnostic approach
based on the region-specific variants.
Possibility of application nuclear magnetic resonance for measurement of fluid-flow
Authors: Kartalovic Nenad , Djekic Saska , Djekic Sasa , Nikezic Dusan , Ramadani Uzahir
Published: July 2021

The paper considers the application of nuclear magnetic resonance for measurement of fluid-flow. The paper is of an experimental nature. Flowmeter based on nuclear magnetic resonance is extremely precise. The combined measurement uncertainty can be 0.1 %. Such a value of measurement uncertainty indicates that it is a matter of a deterministic and not of a stochastic quantity. This high degree of reliability of the method is theoretically and mathematically described. The paper presents a measurement scheme for flow measurement. Water flow measurement was performed on the principle of nuclear magnetic resonance and on the basis of tritiated water (which is considered to be the most accurate classical method). The obtained results show that the measurement of flow based on nuclear magnetic resonance is more accurate (especially at higher flow). This is explained by the higher inertial mass of HTO tritiated water molecules than the standard H2 O mass and the possible transition of tritiated water to H3HeO. In this way, it has been proven that tracing water based on nuclear magnetic resonance is the only real tracing of water by water. The obtained results show that tracing water with tritiated or heavy water is not tracing water by water which is explained by different inertial masses.
Are you scared of what comes next? Students' future career anxiety during the COVID-19 pandemic
Authors: Maftei Alexandra , Holman Andrei-Corneliu , Pătrăuşanu Acnana-Maria
Published: July 2021

In the present study, we explored the mediating effects of depression from COVID-19 (DEPCOVID) and self-esteem (S-EST) on the relationship between fear of COVID-19 (F-COVID) and future career anxiety (C-ANX) in high-school and university students (N = 470, M = 20.17, SD = 2.02, 63.04% females). We were interested in exploring these relationships in both the overall sample and high school students and university students, separately. Our findings suggested that DEP-COVID partially mediated the relationship between F-COVID and C-ANX in both groups (i.e., high-school and university students). Self-esteem was not significantly correlated to our primary variables in high-school students. In university students, as well as the overall sample, results suggested the partially mediating role of S-EST on the relationship between fear of COVID-19 and C-ANX. We discuss our findings concerning the practices that may foster students? career development in turbulent times and consider possible interventions for these specific groups following the COVID-19 pandemic.
Application of solar heating system in high-tech enterprises under the photovoltaic industry chain
Authors: Sun Yixiang , Geng Nana
Published: July 2021

This article designs a simple experimental training platform for high-tech
enterprises to charge solar photovoltaic power generation lead-acid
batteries. The platform comprises photovoltaic panels, charge controllers,
valve-regulated lead batteries, and varistor box loads, indicating that the
solar photovoltaic industry is high-tech, the scope and significance of
application in technology companies. On this basis, the article replaces the
first-order derivation with approximate gradient calculation and proposes a
variable-step voltage disturbance observation method to realize the maximum
power point tracking of solar photovoltaic power generation. The simple
experimental training platform for high-tech solar photovoltaic power
generation lead-acid batteries uses STM8S105 single-chip micro-computer as
the controller core while adopting the Buck DC step-down chopper primary
circuit, combined with the lead-acid battery four-stage charging method, for
system hardware and software design. The experimental test shows that the
experimental training platform has maximum power point tracking function, low
cost, simple structure, good performance, easy operation, and maintenance,
and can meet high-tech enterprises? experimental training requirements.
Modelling and combustion optimization of coal-fired heating boiler based on thermal network
Authors: Chen Chao , Mao Jinhong , Liu Xinzhi , Tian Shan , Song Lijun
Published: July 2021

Based on the thermal network and the MATLartificial intelligence toolkit,
a combustion optimization hybrid modelling of a 300 MW coal-fired power
station boiler is carried out. The boiler is optimized for combustion, and
the weight co?efficient method is used to convert the multi-objective
optimization problem into a single-objective optimization problem. The
results show that the relative error average absolute value of the boiler
thermal efficiency and NOx emission mass concentration calibration samples
are 0.142% and 1.790%, the model has good accuracy and generalization
ability. The weight coefficient method can select the corresponding weight
coefficient according to the actual situation, with the boiler thermal
efficiency or NOx emission mass concentration as the optimization focus,
which has certain guiding significance for combustion optimization.
Thermal simulation model of aero-engine blade material forging simulation
Authors: Dai Huaren , Chen Zhe , Guo Wei , Wang Ju
Published: July 2021

During the high temperature forging process, the thermal parameters such as
the temperature field and strain field in the blank have an important
influence on the crack damage and micro-structure in the forging. We use the
rigid viscoelastic finite element method to carry out the forging process of
a heavy aero-engine blade the finite element numerical simulation was
carried out to obtain the temperature field, strain field and forging load
change law in the forging process with time, and on this basis, combined
with the crack damage and repair mechanism and the re?crystallization
structure evolution law, an optimization was proposed. The forging process
plan. That is, the pre-forging is performed on the basis of the tolerance of
the final forging dimension under pressure of 4 mm, the pre-forging
temperature is 1160?C, and the final forging temperature is 1120?C. The
actual forging process test verifies the feasibility of the process plan,
which is the engineering of this process the application lays the
scientific foundation.
Analysis and research on optimal economic operation of cogeneration micro-grid based on heat pump control
Authors: Xia Wei
Published: July 2021

When the micro-grid is connected to the grid, the influence of the load and
the micropower supply?s operating characteristics may cause the power
exchange between the micro-grid and the large grid to cause unnecessary
losses. The objective function of power supply satisfaction of large power
grids. The article takes the co?generation micro-grid as the research
object. It proposes establishing an objective function including the
satisfaction of micro-grid decision-makers, the satisfaction of social
benefits, and the satisfaction of large-scale power supply using the
analytic hierarchy process. After that, the article uses the particle swarm
optimization algorithm combined with the typical dispatching strategy of
the micro-grid to solve the aforementioned model with MATLas the primary
tool, and obtains the 24 hour output optimization results of the micro-grid,
and analyzes the results in detail. The calculation examples show that the
model can achieve economic optimization based on satisfying the
satisfaction of different groups, which verifies the scientificity and
effectiveness of the proposed model.
Thermal energy constant temperature control system of building energy system based on dynamic analysis method
Authors: Fu Hui
Published: July 2021

If the intelligent building?s indoor environment?s constant temperature is
accurately controlled, the comfort of the building can be improved. When we
perform constant temperature control, there will be large fluctuations in
the supply air temperature, which results in the traditional methods that
cannot control the temperature within a reasonable range. Therefore, the
paper proposes an optimal control method for the indoor environment constant
temperature of intelligent buildings. In the IoT environment, we integrate
the multi-agent technology to design the temperature fuzzy control
structure, determine the input and output variables of the intelligent
building temperature control system and its fuzzy set, use the dynamic
analysis method to modify the fuzzy rules, and integrate it with bilinear
The control algorithm builds a dynamic temperature control model for
intelligent buildings to maintain the indoor temperature at the set value
when the supply air temperature fluctuates significantly. This method makes
up for the shortcomings that the current system cannot adapt to the
intelligent building environment changes. The simulation results show that
compared with the traditional algorithm, the improved algorithm can
significantly improve the robustness of the intelligent building constant
temperature control, and the temperature control stability is vital.
Architecture and application of intelligent heating network system based on cloud computing platform
Authors: Cao Min
Published: July 2021

The vigorous development of Internet-related technologies such as big data,
the IoT, and cloud computing has brought intelligent central heating
networks? intelligent upgrade opportunities. The article discusses the
current situation of the urban central heating system and its intelligence
and analyzes the new characteristics of the intelligent central heating
network under the new situation. Because of the existing central heating
system?s existing problems, we have designed a complete set of sys?tem
architecture and heating networks? application plans.
Calculation accuracy of mathematical homogenization method for thermo-mechanical coupling problems
Authors: Guo Jianxia
Published: July 2021

The paper analyzes the thermo-mechanical couplinag phenomenon under the
condition of sliding contact, establishes the finite element analysis
continuous model of thermo-mechanical coupling, and proposes the system
dynamic equilibrium equation and thermodynamic equilibrium equation. The
article analyzes the contact conditions between the objects in the system
and obtains the objects? contact conditions? mathematical expression. On
this basis, the constraint function is used to express the mathematical
homogenization. We apply the variation principle to the constraint function
and form a non-linear equation group with the system balance equation solve
the thermal-mechanical coupling problem. The example shows that we use the
constraint function method to solve the thermo-mechanical coupling problem,
which has good convergence, stable algorithm, and the calculation result can
reflect the actual situation.
Analysis of a permanent magnet DC motor explosion-removal robot system based on thermal energy optimization control
Authors: Hu Xingzhi
Published: July 2021

Based on the quasi-limit theory?s design principle, the paper analyzes the
steady-state and transient temperature rise laws of the motor with different
overload currents from the heat transfer perspective of permanent magnet DC
motors. The paper takes the EOD robot as an example. Using this law, the
current overload, and temperature rise of the robot wheel motor is analyzed.
The study found that the continuous-duty motor (S1) selected is conservative
and has an extensive design margin.
Glucose Regulation Beyond HbA1c in Type 2 Diabetes Treated With Insulin: Real-World Evidence From the DIALECT-2 Cohort
Authors: den Braber Niala , Vollenbroek-Hutten Miriam M.R. , Westerik Kathryn M. , Bakker Stephan J.L. , Navis Gerjan , van Beijnum Bert-Jan F. , Laverman Gozewijn D.
Published: July 2021

OBJECTIVE

To investigate glucose variations associated with glycated hemoglobin (HbA1c) in insulin-treated patients with type 2 diabetes.

RESEARCH DESIGN AND METHODS

Patients included in Diabetes and Lifestyle Cohort Twente (DIALECT)-2 (n = 79) were grouped into three HbA1c categories: low, intermediate, and high (≤53, 54–62, and ≥63 mmol/mol or ≤7, 7.1–7.8, and ≥7.9%, respectively). Blood glucose time in range (TIR), time below range (TBR), time above range (TAR), glucose variability parameters, day and night duration, and frequency of TBR and TAR episodes were determined by continuous glucose monitoring (CGM) using the FreeStyle Libre sensor and compared between HbA1c categories.

RESULTS

CGM was performed for a median (interquartile range) of 10 (7–12) days/patient. TIR was not different for low and intermediate HbA1c categories (76.8% [68.3–88.2] vs. 76.0% [72.5.0–80.1]), whereas in the low category, TBR was higher and TAR lower (7.7% [2.4–19.1] vs. 0.7% [0.3–6.1] and 8.2% [5.7–17.6] vs. 20.4% [11.6–27.0], respectively; P < 0.05). Patients in the highest HbA1c category had lower TIR (52.7% [40.9–67.3]) and higher TAR (44.1% [27.8–57.0]) than the other HbA1c categories (P < 0.05), but did not have less TBR during the night. All patients had more (0.06 ± 0.06/h vs. 0.03 ± 0.03/h; P = 0.002) and longer (88.0 [45.0–195.5] vs. 53.4 [34.4–82.8] minutes; P < 0.001) TBR episodes during the night than during the day.

CONCLUSIONS

In this study, a high HbA1c did not reduce the occurrence of nocturnal hypoglycemia, and low HbA1c was not associated with the highest TIR. Optimal personalization of glycemic control requires the use of newer tools, including CGM-derived parameters.
COGONGRASS ROOT EXTRACT FROM FIVE DIFFERENT SOILS TYPES FOR SUPPRESSING PURPLE BLOTCH AND INCREASING GROWTH AND YIELD OF SHALLOTS
Authors: Rokhlani Rokhlani , Soesanto Loekas , Nur Subandi , Prihatiningsih Nur
Published: July 2021

Cogongrass root extract from five different soils types for suppressing purple blotch and increasing growth and yield of shallots. The aim of this study was to examine the efficacy of cogongrass (Imperata cylindrica (L.) Beauv.) root extracts from five different soil types (Typic Udipsamments, Aeric Endoaqualfs (=Gleisal Eutrik), Typic Quartzipsamments (=Regosol Eutrik), Aquertic Chromic Hapludalfs, and Pachic Hapludolls) in suppressing purple blotch and increasing growth and yield of shallots. Split plot design was used with 13 treatments repeated three times, and 18 plants plot-1. The treatments consisted of control, fungicide propineb applied before and after inoculation, and five types of cogongrass root extract 50, 60, and 70% concentration applied before and after inoculation. Results showed that cogongrass root extract collected from Pachic Hapludolls which was applied before inoculation had significant effect on the highest pathosystem component indicated by delaying the incubation period, suppressing the intensity of the disease, slowing down the infection rate, and decreasing values of AUDPC as 41.85, 69.87, 75.13, and 67.63%, respectively, compared to control. The cogongrass root extract from Pachic Hapludolls applied before inoculation could increase plant fresh and dry weight plant-1, tuber weight plant-1, plant fresh and dry weight plot-1, and tuber dry weight plot-1 as 42.7, 49.6, 51.92, 66.75, 72.29, and 73.53%, respectively, compared to control.
LA FORMACIÓN INICIAL EN EDUCACIÓN FÍSICA. NOTAS PARA PROBLEMATIZAR LA RELACIÓN ENTRE TEORÍA Y PRÁCTICA EN LA FORMACIÓN TERCIARIA NO UNIVERSITARIA.
Authors: Rodríguez Feilberg Norma Beatriz , Galmez Maria Jimena
Published: July 2021

Este artículo analiza las vinculaciones entre teoría y práctica en la Formación de Profesores/as en Educación Física. La investigación se realizó en el Instituto Superior de Formación Docente Nº 84 de la ciudad de Mar del Plata, provincia de Buenos Aires, Argentina, durante el ciclo lectivo 2020. La hipótesis de trabajo es que la reconversión de la enseñanza mediada por herramientas de educación a distancia -producto de la pandemia por COVID 19- expuso a la Educación Física como un área de conocimiento cuyos límites se delimitan en la práctica.  El estudio implicó un análisis documental y entrevistas a profesores y profesoras en Educación Física que se desempeñan como docentes de la institución. Los resultados muestran que en la formación conviven diversas perspectivas teóricas y que los modos de afrontar la particular coyuntura, producto de la emergencia sanitaria, fueron variados y heterogéneos.
Análisis contable para dinamizar la información exógena DIAN de las empresas del sector pecuario
Authors: Herrera Gutiérrez Estefanía , Cárdenas Londoño Rogelio De Jesús
Published: July 2021

En el presente trabajo se pretende analizar el tipo de estrategias, técnicas y métodos que permiten el análisis contable de las empresas del sector pecuario y que ayudan a dinamizar la información exógena DIAN en el territorio antioqueño, partiendo de cuestionar los tipos de estrategias, técnicas y métodos que hacen o viabilizan el análisis contable en el sector de referencia. Del mismo modo, se caracteriza en el artículo la gestión que soporta el análisis contable y financiero en el campo de las empresas del sector pecuario antioqueño y colombiano a partir de la importancia relativa en términos cuantitativos, en tanto que dichos activos biológicos no se pueden dejar sin medir ni gestionar, habida cuenta de su importante contribución a la creación de valor en la consulta contable como proceso de apoyo a la empresa colombiana. Los distintos estudios emprendidos a la fecha han puesto de manifiesto que para incrementar los análisis contables y financieros corresponde mejorar la información sobre activos biológicos, dado que la que tradicionalmente ha formado parte de la información financiera publicada por las empresas infravalora dichos activos biológicos, con lo cual quedan ocultos valores importantes asociados a ellos.
Ruralidades en américa latina una mirada multidimensional de la pobreza a partir del análisis de componentes principales
Authors: Chacón Me´jía Catalina , Mattei Lauro Francisco , Ramírez Chaparro María Nathalia
Published: July 2021

Teniendo en cuenta las innovaciones metodológicas que ofrecen las mediciones de pobreza multidimensional, especialmente la desagregación que permite por áreas urbana y rural se hace evidente la brecha rural de manera particular en los países latinoamericanos. A razón de ello, se plantea organizar los grupos de países que se encuentran en situaciones similares, haciendo uso de Análisis de Componentes Principales. Por otra parte, con un Análisis de Correspondencia Canónica se demuestra la cercanía que tienen los países respecto a las dimensiones del índice de pobreza multidimensional, mostrando gráficamente tal comportamiento de manera simultánea. Este análisis regional de pobreza servirá para que los diferentes organismos puedan diseñar políticas conjuntas que superen la situación presentada. Además, responden a la necesidad de adelantar acciones conjuntas para disminuir la pobreza en la región.
La capacidad contributiva como elemento de la justicia tributaria
Authors: Ríos Obando Julián Andrés , Sánchez Vásquez Lina Marcela , Restrepo Pineda Carlos Mario
Published: July 2021

El artículo presenta la reflexión sobre el concepto de capacidad contributiva con un enfoque analítico comparado, a partir de la revisión teórica y normativa que sustenta la teoría de la justicia en sus aspectos filosóficos, económicos y tributarios las bases que cimientan los principios tributarios. Posteriormente se reconocen las dimensiones y aspectos que contempla como criterios la determinación de capacidad de contribución con el propósito de indicar si su consideración se convierte en una forma efectiva de generar justicia tributaria. De la reflexión se permite indicar que la existencia de aspectos subjetivos y objetivos al definir capacidad contributiva implica la necesidad de generar diálogos con la realidad a que atiende el sistema tributario para reconocer los aspectos contextuales que inciden en la calidad de vida y condiciones favorables de desarrollo social.
META ANALISIS: PENGARUH PENERAPAN PENDEKATAN REALISTIC MATHEMATICS EDUCATION TERHADAP HASIL BELAJAR SISWA DI SEKOLAH DASAR
Authors: Nur Fitriani , Angriani Andi Dian
Published: July 2021

AbstrakPenelitian ini bertujuan untuk melakukan analisis terkait penerapan pendekatan Realistic Mathematics Education (RME) terhadap hasil belajar matematika siswa di Sekolah Dasar (SD). Jenis penelitian yang digunakan yaitu meta analisis dengan mengumpulkan data non tes, yakni menelusuri terbitan berkala ilmiah atau jurnal melalui google scholar dan DOAJ. Dari hasil penelusuran diperoleh 25 artikel dari jurnal dengan beberapa kriteria, diantaranya: (1) artikel berkaitan dengan pengaruh RME terhadap hasil belajar siswa, (2) penelitian dilakukan dalam kurung waktu 2013-2020, (3) penelitian dilaksanakan jenjang sekolah dasar, (4) penelitian dilakukan di Indonesia, (5) jenis penelitian yang digunakan adalah penelitian eksperimen yang melibatkan dua kelompok, yaitu kelompok eksperimen dan kelompok control, (6) kelas kontrol menggunakan model pembelajaran konvensional, dan (7) data yang dibutuhkan untuk menentukan effect size lengkap pada artikel. Analisis data menggunakan teknik statistik deskriptif dan statistik inferensial. Hasil penelitian ini menemukan bahwa pendekatan RME efektif digunakan ditinjau dari hasil belajar matematika siswa. Implikasi dari hasil temuan ini memberikan gambaran bahwa pendekatan Realistic Mathematics Education (RME) memiliki kekuatan yang besar dalam meningkatkan hasil belajar matematika sehingga pendekatan tersebut menjadi pilihan yang tepat dalam proses pembelajaran matematika siswa sekolah dasar.AbstractThis study aimed to analyze the implementation of the Realistic Mathematics Education (RME) approach to students’ mathematics learning outcomes in elementary schools (SD). The research type used was a meta-analysis by collecting non-test data, namely periodical papers or journals through google scholar and DOAJ. The search results obtained 26 articles from journals with several criteria, including: (1) articles related to the effect of RME on students’ learning outcomes, (2) those researches were conducted in 2013-2020 periods, (3) those researches were carried out in elementary school level; (4) those researches were conducted in Indonesia, (5) the method used was experimental research involving two groups, namely experimental group and control group, (6) the control group used a conventional learning model, and (7) data were needed to determine the complete effect size of the articles. The data analysis techniques used in this study were descriptive and inferential statistics. Thus, this study found that the RME approach was effectively used for the students’ mathematics learning outcomes. The implications of this finding indicated that the Realistic Mathematics Education (RME) approach had great power in improving mathematics learning outcomes so that the approach is appropriately used in learning mathematics in elementary school.