bluuebunny/crossref_metadata_2025 huggingface dataset:
New Insights Into the Physiology of Bone Regulation: the Role of Neurohormones
Authors: ŽOFKOVÁ I. , MATUCHA P.
Published: November 2020

Bone metabolism is regulated by interaction between two skeletal cells – osteoclasts and osteoblasts. Function of these cells is controlled by a number of humoral factors, including neurohormones, which ensure equilibrium between bone resorption and bone formation. Influence of neurohormones on bone metabolism is often bimodal and depends on the tissue, in which the hormone is expressed. While hypothalamic beta-1 and beta-2-adrenergic systems stimulate bone formation, beta-2 receptors in bone tissue activate osteoclatogenesis and increases bone resorption. Chronic stimulation of peripheral beta-2 receptors is known to quicken bone loss and alter the mechanical quality of the skeleton. This is supported by the observation of a low incidence of hip fractures in patients treated with betablockers. A bimodal osteo-tropic effect has also been observed with serotonin. While serotonin synthetized in brain has osteo-anabolic effects, serotonin released from the duodenum inhibits osteoblast activity and decreases bone formation. On the other hand, both cannabinoid systems (CB1 receptors in the brain and CB2 in bone tissue) are unambiguously osteo-protective, especially with regard to the aging skeleton. Positive (protective) effects on bone have also been shown by some hypophyseal hormones, such as thyrotropin (which inhibits bone resorption) and adrenocorticotropic hormone and oxytocin, both of which stimulate bone formation. Low oxytocin levels have been shown to potentiate bone loss induced by hypoestrinism in postmenopausal women, as well as in girls with mental anorexia. In addition to reviewing neurohormones with anabolic effects, this article also reviews neurohormones with unambiguously catabolic effects on the skeleton, such as neuropeptide Y and neuromedin U. An important aim of research in this field is the synthesis of new molecules that can stimulate osteo-anabolic or inhibiting osteo-catabolic processes.
DESIGN, SIMULATION AND IMPLEMENTATION MONITORING SYSTEM FOR SYSTEM CONTROL C4 FEEDING PUMP FOR FEED VAPORIZATION IN THE BUTADIENE PLANT
Authors: Yunistyawan Fahmi , Berchmans Yunistyawan J , Baskoro Gembong
Published: November 2020

This study implements the auto start control system on an electric motor 3 phase C4Feeding pump when the discharge pressure is low-low (4.3 kg /cm²). The C4 feeding pumpmotor was initially manually operated from the local control station, this was very ineffectiveand inefficient because it still relied on the field operator to operate the pump motor and whenthe plant was in normal operating it is very risk if the field operator late to operate motor then itwill impact to quality of the product, and if the delay time to operate motor is too long then planthave to shut down, therefore improvement is needed in the C4 feeding pump motor controlsystem. In this paper, various types of 3-phase motor control are explained which allow it to beapplied to the C4 feeding pump motor that are on-off, inverter, and variable speed drive andefficient selection of the three systems control of the motor. Software and hardware used in thisthesis work are DCS CENTUM VP Yokogawa.
DEVELOPMENT OF 3-DIMENSIONAL SNAKE AND LADDER GAME: IMPLEMENTATION WITH SECOND GRADE STUDENTS OF SDN 37 PEKANBARU
Authors: Febriyanti Dian , Putra Zetra Hainul , Witri Gustimal
Published: November 2020

This study aims to test the feasibility of a three-dimensional snake and ladder  game to reflect the thematic learning material from theme 6 subthemes 2 about taking care of animals around me. This study was conducted in June 2020 in one of  second grade parent house of SD N 37 Pekanbaru. This research is motivated by the lack of learning media that can be used to primary school students. The learning outside learning hours is important for students to be able to have leraning activities, working together in groups, respecting friends' opinions and interacting. The 3D snake and ladder game is an interesting game. The development of 3D snake and ladder game is carried out according to the Research and Development (R&D) method according to the procedure of ADDIE development models. The feasibility test of 3D snake and ladder game product had validation rate of 87.5% from the media expert in the "very acceptable" category and 92.5% from the content expert in the "very acceptable" category. Student responses to the snake and ladder game developed as a whole scored 95.97% in the "excellent" category.
Early signs of hypertension-mediated brain damage: case report and possibilities of citicoline
Authors: Ostroumova Т. М. , Ostroumova О. D. , Golovina О. V.
Published: November 2020

Cognitive impairment (CI) are the main clinical symptom of hypertension-mediated brain damage and are present at the earliest stages of the disease. Classification of CI and clinical approach for patients with hypertension and CI are presented. A case report of a typical patient with hypertension and mild CI and their treatment is described. Evidence based management of CI with citicoline is discussed.
Mechanisms of liver damage in COVID-19
Authors: Pinchuk T. V. , Orlova N. V. , Suranova T. G. , Bonkalo T. I.
Published: November 2020

At the end of 2019, a new coronavirus (SARS-CoV-2) was discovered in China, causing the coronavirus infection COVID-19.The ongoing COVID-19 pandemic poses a major challenge tohealth systems around the world. There is still little informationon how infection affects liver function and the significanceof pre-existing liver disease as a risk factor for infection andsevere COVID-19. In addition, some drugs used to treat thenew coronavirus infection are hepatotoxic. In this article, weanalyze data on the impact of COVID-19 on liver function, aswell as on the course and outcome of COVID-19 in patients withliver disease, including hepatocellular carcinoma, or those onimmunosuppressive therapy after liver transplantation.
Frailty syndrome in patients with coronary artery disease
Authors: Krivoshapova K. E. , Vegner E. A. , Terentyeva N. A. , Masenko V. L. , Grigoryeva I. I. , Kokov A. N. , Bazdyrev E. D. , Raskina T. A. , Barbarash O. L.
Published: November 2020

Aim. To assess the prevalence of frailty and describe clinical features of frail patients with stable coronary artery disease (CAD). Methods. 387 patients admitted to the hospital for elective primary coronary artery bypass grafting (CABG) were recruited in the study. Clinical data, demographic data, and the results of the instrumental examinations were collected for each subject. The primary screening of prefrailty and frailty in patients before the surgery was performed using the ’Age is not a hindrance’ questionnaire. The results were processed using the IBM SPSS Statistics 26.0.0 software package. A value of p ≤ 0.050 was considered statistically significant. Results. Frailty was found in 19% of patients with coronary artery disease and multivessel coronary artery disease before open myocardial revascularization, while 58% of patients had prefrailty. The presence of frailty and prefrailty was associated with older and advanced age (p = 0.003), female sex (p = 0.001), type 2 diabetes mellitus (p = 0.006), as well as with comorbidities, including cerebral atherosclerosis (p = 0.020), and heart rhythm disturbances (p = 0.050). Conclusion. The results obtained in this study are consistent with other studies reporting higher levels of comorbidities among frail patients.
COMBINED METHOD FOR CLEANING PIPES FROM SOIL CORE
Authors: Tishchenko Igor V.
Published: November 2020

The paper is devoted to solving an urgent problem - improving the technology of soil excavation during trenchless pipe laying by vibro-impact pushing with the leading steel casing of the well. A new method for core extraction is proposed, which is based on the effect of its vibration transportation under the influence of combined static-dynamic load. The optimum level of soil moisture is experimentally determined, which contributes to a decrease in lateral friction when it moves along a metal pipe cavity. The results of pilot tests on cleaning a pipe 530 mm in diameter, immersed in soil at full design length of transition using Typhoon-190 pneumatic hammer with a mass of 190 kg are presented. The velocity characteristic of core displacement at changing its moisture content is obtained.
JUSTIFICATION OF THE PARAMETERS OF CHILLING ZONE OF LINING OF NEAR-ENTRANCE SITE OF LONG RAILWAY TUNNELS IN COLD SEASON
Authors: Kiyanitsa Lavrentiy A. , Lugin Ivan V.
Published: November 2020

When operating long railway tunnels in harsh climatic conditions of Siberia and the Far East, there is a problem of tunnel lining freezing on near-entrance sites in the cold season. Due to the cyclical effects of negative outside temperatures, the surface layer of tunnel lining is constantly freezing and thawing, which causes rapid frost deterioration. This effect is especially pronounced for tunnels with closing near-entrance gates and one-way train traffic on the exit site. This is explained by the fact that at each train passage through the exit site, a significant amount of cold atmospheric air enters the tunnel. The length of chilling zone and the temperature of tunnel lining in the “outside air - tunnel lining” contact zone from the exit site deep into the tunnel, depending on the technological and climatic parameters of the tunnel are justified by analyzing the results of computational experiment. The correctness of obtained regularities is justified by the convergence of experimental results and analytical calculations based on the displacement method.
Measuring Success from Below: The Social Legitimacy of the United Nations among Populations Exposed to its Peacekeeping Operations
Authors: Haran Diman Amiad
Published: November 2020

The success of peacekeeping forces is both a topic of heated debate in the literature on international peacekeeping. Most existing answers to this question rely on one- dimensional measures of effectiveness. This paper proposes another perspective based on the point of view of local residents in host countries. It argues that their support is an indicator of success, since they evaluate the institutional effectiveness of the peacekeepers. Using longitudinal data from the World Values Survey (N=25,196), and original data on the exposure to peacekeepers, we offer a systematic and cross-national measurement of the local legitimacy of peacekeeping forces. Results from a multilevel linear model show significantly lower levels of confidence in the United Nations in countries with an active peacekeeping operation. The level of confidence has a strong negative correlation with the size of the mission, even when controlled for varied ideological explanations and for confidence extrapolation.
Study of Bacterial Aetiogenicity of Pigment Gall Stones by Culture of Nidus of Calculus and correlation between Stone Culture and Bile Culture
Authors: Shiekh Mahmood Rashid , Sheera Tahleel , Rashid Sheikh Aamir , Sheera Altaf Hussain , Ahmad Junaid
Published: November 2020

Background: Calculus disease of biliary tract is a major public health problem in north Kashmir and pigment gall stones form a significant portion of gall stones in our region. In this study we prospectively studied 84 cases of pigment gall stones to examine the role of bacteria in the formation of these stones.

Objective: To study the bacterial aetiology of pigment gall stones.

Methods: A hospital based prospective study of 84 consecutive cases of pigment gall stones was done from December 2012 to November 2019 and the results of stone culture and bile culture were statistically analysed. Informed consent was obtained from all the patients in the study group.

Results: A total of 84 cases studied included 32 (38.09%) male patients and 52(61.91%) females patients. The median age was 48.5 years and mean age was 46.2 years. Of 84 patients, 21(25.00%) had black pigment stones and 63 (75.00%) had brown pigment stones. 61 (72.62%) patients presented with biliary colic and 24(28.57%) patients had chronic cholecystitis . Bile culture was positive in 46 (54.76%) patients and stone culture was positive in 70(83.33%) patients.

Conlusion: A strong association was observed between stone culture and bile culture results (showing similar beta-glucronidase producing bacteria) and pigment stone formation.
Adoption Of Telemedicine -need of the hour
Authors: Chitturi Sridhar
Published: November 2020

I would like to describe our experience in telemedicine for the provision of health care in the Northern Territory of Australia and its relevance for the state of Jammu and Kashmir. Northern Territory is a large landmass spread over 1.4 million square kilometers with a population of only 250,000. Major healthcare facilities are located in cities of Darwin and Alice Springs with smaller hospitals in Katherine, Gove, and Tennant Creek. Many small communities are located in remote areas with limited access to health care. We have adopted telemedicine more than a decade ago and gradually scaled up the services which came handy during the latest pandemic due to SARS-CoV-2.
SNORA72 Activates the Notch1/c-Myc Pathway to Promote Stemness Transformation of Ovarian Cancer Cells
Authors: Zhang Liwen , Ma Rong , Gao Mengcong , Zhao Yanyun , Lv Xuemei , Zhu Wenjing , Han Li , Su Panpan , Fan Yue , Yan Yuanyuan , Zhao Lin , Ma Heyao , Wei Minjie , He Miao
Published: November 2020

Cancer stem cells (CSCs) are responsible for the migration and recurrence of cancer progression. Small nucleolar RNAs (snoRNAs) play important roles in tumor development. However, how snoRNAs contribute to the regulation of the stemness of ovarian CSCs (OCSCs) remains unclear. In the present study, we found that SNORA72 was significantly upregulated in OVCAR-3 spheroids (OS) and CAOV-3 spheroids (CS) with the OCSC characteristics attained by serum-free culture in a suspension of OVCAR-3 (OV) and CAOV-3 (CA) cells. The overexpression of SNORA72 increased self-renewal abilities and migration abilities in OV and CA cells and upregulated the expressions of the stemness markers Nanog, Oct4, and CD133. In addition, the ectopic expression of SNORA72 can elevate the messenger RNA (mRNA) and protein expression levels of Notch1 and c-Myc in parental cells. The opposite results were observed in SNORA72-silenced OCSCs. Moreover, we found that Notch1 knockdown inversed the migration abilities and self-renewal abilities raised by overexpressing SNORA72. In summary, stemness transformation of ovarian cancer cells can be activated by SNORA72 through the Notch1/c-Myc pathway. This study introduces a novel therapeutic strategy for improving the treatment efficiency of ovarian cancer.
Bevacizumab Plus FOLFOX-4 Combined With Deep Electro-Hyperthermia as First-line Therapy in Metastatic Colon Cancer: A Pilot Study
Authors: Ranieri Girolamo , Laface Carmelo , Laforgia Mariarita , De Summa Simona , Porcelli Mariangela , Macina Francesco , Ammendola Michele , Molinari Pasquale , Lauletta Gianfranco , Di Palo Alessandra , Rubini Giuseppe , Ferrari Cristina , Gadaleta Cosmo Damiano
Published: November 2020

Bevacizumab plus FOLFOX-4 regimen represents the first-line therapy in patients affected by metastatic colorectal cancer (mCRC). Hyperthermia has been considered an effective ancillary treatment for cancer therapy through several anti-tumor mechanisms, sharing with Bevacizumab the inhibition of angiogenesis. Up to now, scientific literature offers very few clinical data on the combination of bevacizumab plus oxaliplatin-based chemotherapy with deep electro-hyperthermia (DEHY) for metastatic colon cancer (mCC) patients. Therefore, we aimed at evaluating the efficacy of this combination based on the possible interaction between the DEHY and bevacizumab anti-tumor mechanisms. We conducted a retrospective analysis on 40 patients affected by mCC treated with the combination of bevacizumab plus FOLFOX-4 (fluorouracil/folinic acid plus oxaliplatin) and DEHY (EHY2000), between January 2017 and May 2020. DEHY treatment was performed weekly, with capacitive electrodes at 80–110 W for 50 min, during and between subsequent bevacizumab administrations, on abdomen for liver or abdominal lymph nodes metastases and thorax for lung metastases. Treatment response assessment was performed according to the Response Evaluation Criteria for Solid Tumors (RECIST). The primary endpoints were disease control rate (DCR) and progression-free survival (PFS). The secondary endpoint was overall survival (OS). DCR, counted as the percentage of patients who had the best response rating [complete response (CR), partial response (PR), or stable disease (SD)], was assessed at 90 days (timepoint-1) and at 180 days (timepoint-2). DCR was 95% and 89.5% at timepoint-1 and timepoint-2, respectively. The median PFS was 12.1 months, whereas the median OS was 21.4 months. No major toxicity related to DEHY was registered; overall, this combination regimen was safe. Our results suggest that the combined treatment of DEHY with bevacizumab plus FOLFOX-4 as first-line therapy in mCC is feasible and effective with a favorable disease control, prolonging PFS of 2.7 months with respect to standard treatment without DEHY for mCC patients. Further studies will be required to prove its merit and explore its potentiality, especially if compared to conventional treatment.
Women’s Entrepreneurship in the Global South: Empowering and Emancipating?
Authors: Ojediran Funmi (Olufunmilola) , Anderson Alistair
Published: November 2020

This paper addresses the following questions: Are women entrepreneurs empowered by entrepreneurship, and critically, does entrepreneurship offer emancipation? Our theoretical position is that entrepreneurship is socially embedded and must be recognized as a social process with economic outcomes. Accordingly, questions of empowerment must take full account of the context in which entrepreneurship takes place. We argue that institutions—formal and informal, cultural, social, and political—create gendered contexts in the Global South, where women’s entrepreneurship is subjugated and treated as inferior and second class. Our thematic review of a broad scope of the literature demonstrates that in different regions of the Global South, women entrepreneurs confront many impediments and that this shapes their practices. We show how the interplay of tradition, culture, and patriarchy seem to conspire to subordinate their efforts. Yet, we also recognize how entrepreneurial agency chips away and is beginning to erode these bastions, in particular, how role models establish examples that undermine patriarchy. We conclude that entrepreneurship can empower but modestly and slowly. Some independence is achieved, but emancipation is a long, slow game.
Pressure Algometry Validation and Determination of Efficacy of Articaine Hydrochloride Ring Block in Antler Removal in Red Deer (Cervus elaphus)
Authors: Sahebjam Farzin , Kongara Kavitha , Chambers John Paul , Walker Ruth Ellen , Naffa Rafea , Lopez-Villalobos Nicolas , Singh Preet Mohinder
Published: November 2020

New Zealand deer farming centres on the production of meat and velvet antler. Velvet antler removal is a painful procedure and currently, New Zealand Animal Welfare regulations dictate surgical removal of velvet antlers under lignocaine anaesthesia. To improve our knowledge on the efficacy and duration of other local anaesthetics to mitigate pain after antler removal, it is important to accurately assess and quantify pain arising from antler removal. Therefore, the current study was designed to validate mechanical nociceptive threshold (MNT) testing using a Wagner hand-held algometer, and to apply this methodology to assess the efficacy and duration of action of articaine for antler removal in deer. Baseline force (N) required to elicit the nociceptive response was recorded in 40 yearling male red deer on three alternate days. Ten of the 40 animals were selected for antler removal after administration of 4% articaine hydrochloride as a ring block. The duration of analgesic efficacy of articaine was assessed by algometry across 5 time points. There was a significant difference in MNTs among the three days (day 3 versus day 1 (p < 0.0001), day 2 versus day 1 (p < 0.0001), and day 1 versus day 2 (p < 0.01)). Positive correlations were observed between weight, antler length and thresholds. The MNT values remained above 20N for 6 h after removal of velvet antlers under the articaine ring block. This study provides valuable information about the use of MNT in red deer. These findings lay a foundation for future studies in the topics of peri-operative and postoperative pain management in deer antler removal, and a possible alternative use for articaine.
Soiling of Pig Pens: A Review of Eliminative Behaviour
Authors: Nannoni Eleonora , Aarnink André J.A. , Vermeer Herman M. , Reimert Inonge , Fels Michaela , Bracke Marc B.M.
Published: November 2020

This is a comprehensive review on the pigs’ normal eliminatory behaviour (i.e., defaecation and urination) and pen soiling. This review is aimed primarily at solving issues with pen soiling in current systems, and ultimately at the future design of a well-functioning pig toilet, which we intend to elaborate on in a subsequent publication. In this paper, first, normal elimination is described in relation to what is known about its phylogeny, ontogeny, causation, and function, i.e., according to Tinbergen’s four why questions concerning animal behaviour. Then, pen soiling is described as if it were a medical disorder, highlighting its importance, aetiology, symptoms, diagnosis, pathogenesis, treatment, and prevention. Due to its negative consequences in terms of animal welfare, health, workload, and environmental emissions, possible methods to address pen soiling in current systems are described. Probably, pigs do not choose a specific place to eliminate but rather choose the most comfortable place for resting, and avoid eliminating there. We identified four main strategies to reduce pen soiling: (1) reducing the suitability of the designated elimination area to be used for other functions, especially resting or thermoregulation; (2) improving the suitability of other functional areas in the pen to be used for their specific function, such as resting and activity; (3) reducing the suitability of other functional areas to be used for elimination; and (4) improving the suitability of the elimination area for elimination. These prevention strategies and the encompassing disease framework provide a structured approach to deal with pen soiling in existing systems and to support the future design, development, and implementation of a well-functioning pig toilet that can help to achieve some of the main goals of modern pig production, namely reducing environmental emissions as well as substantially improving pig welfare.
A Comprehensive Review on Source, Types, Effects, Nanotechnology, Detection, and Therapeutic Management of Reactive Carbonyl Species Associated with Various Chronic Diseases
Authors: Fuloria Shivkanya , Subramaniyan Vetriselvan , Karupiah Sundram , Kumari Usha , Sathasivam Kathiresan , Meenakshi Dhanalekshmi Unnikrishnan , Wu Yuan Seng , Guad Rhanye Mac , Udupa Kaviraja , Fuloria Neeraj Kumar
Published: November 2020

Continuous oxidation of carbohydrates, lipids, and amino acids generate extremely reactive carbonyl species (RCS). Human body comprises some important RCS namely hexanal, acrolein, 4-hydroxy-2-nonenal, methylglyoxal, malondialdehyde, isolevuglandins, and 4-oxo-2- nonenal etc. These RCS damage important cellular components including proteins, nucleic acids, and lipids, which manifests cytotoxicity, mutagenicity, multitude of adducts and crosslinks that are connected to ageing and various chronic diseases like inflammatory disease, atherosclerosis, cerebral ischemia, diabetes, cancer, neurodegenerative diseases and cardiovascular disease. The constant prevalence of RCS in living cells suggests their importance in signal transduction and gene expression. Extensive knowledge of RCS properties, metabolism and relation with metabolic diseases would assist in development of effective approach to prevent numerous chronic diseases. Treatment approaches for RCS associated diseases involve endogenous RCS metabolizers, carbonyl metabolizing enzyme inducers, and RCS scavengers. Limited bioavailability and bio efficacy of RCS sequesters suggest importance of nanoparticles and nanocarriers. Identification of RCS and screening of compounds ability to sequester RCS employ several bioassays and analytical techniques. Present review describes in-depth study of RCS sources, types, properties, identification techniques, therapeutic approaches, nanocarriers, and their role in various diseases. This study will give an idea for therapeutic development to combat the RCS associated chronic diseases.
New Oleoyl Hybrids of Natural Antioxidants: Synthesis and In Vitro Evaluation as Inducers of Apoptosis in Colorectal Cancer Cells
Authors: Carullo Gabriele , Mazzotta Sarah , Koch Adrian , Hartmann Kristin M. , Friedrich Oliver , Gilbert Daniel F. , Vega-Holm Margarita , Schneider-Stock Regine , Aiello Francesca
Published: November 2020

Nowadays, the beneficial role of a healthy lifestyle, particularly emphasizing the quality of foods and cancer management, is accepted worldwide. Polyphenols and oleic acid play a key role in this context, but are still scarcely used as anti-cancer agents due to their bio-accessibility limits. Therefore, we aimed to synthesize a set of new oleoyl-hybrids of quercetin, morin, pinocembrin, and catechin to overcome the low bioavailability of polyphenols, throughout a bio-catalytic approach using pancreatic porcine lipase as a catalyst. The in vitro assays, using a wide panel of human cancer cell lines showed, mainly for two novel regioisomer oleoyl-hybrids of quercetin, a remarkable increase in apoptotic cell populations. We suggested that the DNA damage shown as ɣH2AX signals might be the major cause of apoptotic cell death. Finally, we demonstrated convincing data about two novel polyphenol-based hybrids displaying a highly selective anti-cancer cytotoxicity and being superior compared to their reference/parental compounds.
ROS and NO Regulation by Melatonin Under Abiotic Stress in Plants
Authors: Pardo-Hernández Miriam , López-Delacalle Maria , Rivero Rosa M.
Published: November 2020

Abiotic stress in plants is an increasingly common problem in agriculture, and thus, studies on plant treatments with specific compounds that may help to mitigate these effects have increased in recent years. Melatonin (MET) application and its role in mitigating the negative effects of abiotic stress in plants have become important in the last few years. MET, a derivative of tryptophan, is an important plant-related response molecule involved in the growth, development, and reproduction of plants, and the induction of different stress factors. In addition, MET plays a protective role against different abiotic stresses such as salinity, high/low temperature, high light, waterlogging, nutrient deficiency and stress combination by regulating both the enzymatic and non-enzymatic antioxidant defense systems. Moreover, MET interacts with many signaling molecules, such as reactive oxygen species (ROS) and nitric oxide (NO), and participates in a wide variety of physiological reactions. It is well known that NO produces S-nitrosylation and NO2-Tyr of important antioxidant-related proteins, with this being an important mechanism for maintaining the antioxidant capacity of the AsA/GSH cycle under nitro-oxidative conditions, as extensively reviewed here under different abiotic stress conditions. Lastly, in this review, we show the coordinated actions between NO and MET as a long-range signaling molecule, regulating many responses in plants, including plant growth and abiotic stress tolerance. Despite all the knowledge acquired over the years, there is still more to know about how MET and NO act on the tolerance of plants to abiotic stresses.
The Influence of Ski Waist-Width and Fatigue on Knee-Joint Stability and Skier’s Balance
Authors: Zorko Martin , Hirsch Karmen , Šarabon Nejc , Supej Matej
Published: November 2020

Alpine skiing is a complex sport that demands a high level of motor control and balance. In general, skiers are prone to deterioration in the state of fatigue due to using inappropriate equipment. As a consequence, the risk of injury might increase. This study aimed to examine the influence of fatigue and ski waist-width on knee-joint stability and skier’s balance. A laboratory skiing simulation in a quasistatic ski-turning position was conducted where the lower-limb kinematics was recorded using an optical system, and the balance-determining parameters were captured using a force plate. It was demonstrated that the knee-joint kinematics and skier’s balance were hampered in the state of fatigue, as well as when using skis with a large waist-width. The results of the study suggest avoiding the fatigue state and the use of skis having a large waist-width while skiing on hard surfaces to decrease the risk of injury.
Scaling Law, Confined and Surface Modes in Photonic Fibonacci Stub Structures: Theory and Experiment
Authors: Aynaou Hassan , Mouadili Abdelkader , Ouchani Noama , El Boudouti El Houssaine , Akjouj Abdellatif , Djafari-Rouhani Bahram
Published: November 2020

We investigate both theoretically and experimentally the properties of electromagnetic waves propagation and localization in periodic and quasi-periodic stub structures of Fibonacci type. Each block constituting the Fibonacci sequence (FS) is composed of an horizontal segment and a vertical stub. The origin of the primary and secondary gaps shown in such systems is discussed. The behaviors and scattering properties of the electromagnetic modes are studied in two geometries, when the FS is inserted horizontally between two semi-infinite waveguides or grafted vertically along a guide. Typical properties of the Fibonacci systems such as the fragmentation of the frequency spectrum, the self-similarity following a scaling law are analyzed and discussed. It is found that certain modes inside these two geometries decrease according to a power law rather than an exponential law and the localization of these modes displays the property of self-similarity around the central gap frequency of the periodic structure where the quasi-periodicity is most effective. Also, the eigenmodes of the FS of different generation order are studied depending on the boundary conditions imposed on its extremities. It is shown that both geometries provide complementary information on the localization of the different modes inside the FS. In particular, in addition to bulk modes, some localized modes induced by both extremities of the system exhibit different behaviors depending on which surface they are localized. The theory is carried out using the Green’s function approach through an analysis of the dispersion relation, transmission coefficient and electric field distribution through such finite structures. The theoretical findings are in good agreement with the experimental results performed by measuring in the radio-frequency range the transmission along a waveguide in which the FS is inserted horizontally or grafted vertically.
Numerical Evaluation of the Transient Performance of Rock-Pile Seasonal Thermal Energy Storage Systems Coupled with Exhaust Heat Recovery
Authors: Amiri Leyla , de Brito Marco Antonio Rodrigues , Ghoreishi-Madiseh Seyed Ali , Bahrani Navid , Hassani Ferri P. , Sasmito Agus P.
Published: November 2020

This study seeks to investigate the concept of using large waste rocks from mining operations as waste-heat thermal energy storage for remote arctic communities, both commercial and residential. It holds its novelty in analyzing such systems with an experimentally validated transient three-dimensional computational fluid dynamics and heat transfer model that accounts for interphase energy balance using a local thermal non-equilibrium approach. The system performance is evaluated for a wide range of distinct parameters, such as porosity between 0.2 and 0.5, fluid velocity from 0.01 to 0.07 m/s, and the aspect ratio of the bed between 1 and 1.35. It is demonstrated that the mass flow rate of the heat transfer fluid does not expressively impact the total energy storage capacity of the rock mass, but it does significantly affect the charge/discharge times. Finally, it is shown that porosity has the greatest impact on both fluid flow and heat transfer. The evaluations show that about 540 GJ can be stored on the bed with a porosity of 0.2, and about 350 GJ on the one with 0.35, while the intermediate porosity leads to a total of 450 GJ. Additionally, thermal capacity is deemed to be the most important thermophysical factor in thermal energy storage performance.
Real-Time Path Planning for Strategic Missions
Authors: Vasconcelos João Vítor R. , Brandão Alexandre S. , Sarcinelli-Filho Mário
Published: November 2020

Robot navigation is still an open research topic, mainly regarding applications that require online planning. In this context, this manuscript presents an implementation of the Lifelong Planning A* (LPA*) search algorithm to guide a mobile robot in an environment that changes along time, by detecting obstacles and updating the current mapping information. Firstly, simulations validate the strategy, and later experiments confirm these results considering a real application. The result is that the LPA* algorithm is able to guide the mobile robot to its target in a changing environment. Obstacles are interactively included in the scene to force the route redesign and the seeking for a new optimal solution connecting the current robot position and its target position.
Fatigue Life Assessment in Bainitic Steels Based on The Cumulative Strain Energy Density
Authors: Martins Rui F. , Branco Ricardo , Long Xiaoyan
Published: November 2020

Carbide-free bainitic steels are an example of high-strength steels that show an excellent combination of strength, ductility, toughness and rolling fatigue contact resistance and are progressively being introduced in the production of railways, crossings and automotive components. Although there are Mn-free approaches able to produce carbide-free bainitic steels, those based on the addition of Mn are less expensive. Therefore, it is important to fully understand the mechanical behavior of such materials to develop reliable engineering products. In this paper, three low-carbon bainitic steels, differing in Mn content, namely 0%, 2.3% and 3.2%, designated as steel A, B and C, respectively, were studied in a systematic manner. Low-cycle fatigue tests were conducted under symmetrical strain-controlled conditions for different strain amplitudes (0.6%, 0.7%, 0.8% and 1%). Independent of Mn content, a strong relationship between cumulative strain energy density and number of cycles to failure was found. Based on this relationship, a new predictive model, capable of estimating the fatigue lifetime, was developed. Predictions based on the new model were close to the experimental lives and were more accurate than those computed via the well-known Smith-Watson-Topper (SWT) and Liu criteria.
The Deep 3D Convolutional Multi-Branching Spatial-Temporal-Based Unit Predicting Citywide Traffic Flow
Authors: Ul Abideen Zain , Sun Heli , Yang Zhou , Ali Amir
Published: November 2020

Recently, for public safety and traffic management, traffic flow prediction is a crucial task. The citywide traffic flow problem is still a big challenge in big cities because of many complex factors. However, to handle some complex factors, e.g., spatial-temporal and some external factors in the intelligent traffic flow forecasting problem, spatial-temporal data for urban applications (i.e., travel time estimation, trajectory planning, taxi demand, traffic congestion, and the regional rainfall) is inherently stochastic and unpredictable. In this paper, we proposed a deep learning-based novel model called “multi-branching spatial-temporal attention-based long-short term memory residual unit (MBSTALRU)” for the citywide traffic flow from lower-level layers to high-level layers, simultaneously. In our work, initially, we have modeled the traffic flow with spatial correlations multiple 3D volume layers and propose the novel multi-branching scheme to control the spatial-temporal features. Our approach is useful for exploring temporal dependencies through the 3D convolutional neural network (CNN) multiple branches, which aim to merge the spatial-temporal characteristics of historical data with three-time intervals, namely closeness, daily, and weekly, and we have embedded features by attention-based long-short term memory (LSTM). Then, we capture the correlation between traffic inflow and outflow with residual layers units. In the end, we merge the external factors dynamically to predict citywide traffic flow simultaneously. The simulation results have been performed on two real-world datasets, BJTaxi and NYCBike, which show better performance and effectiveness of the proposed method than previous state-of-the-art models.
Sensitivity and Calibration of the FT-IR Spectroscopy on Concentration of Heavy Metal Ions in River and Borehole Water Sources
Authors: Mamera Matthew , van Tol Johan J. , Aghoghovwia Makhosazana P. , Kotze Elmarie
Published: November 2020

Heavy metals in water sources can threaten human life and the environment. The analysis time, need for chemical reagents, and sample amount per analysis assist in monitoring contaminants. Application of the Fourier Transform Infrared (FT-IR) Spectroscopy for the investigation of heavy metal elements has significantly developed due to its cost effectiveness and accuracy. Use of chemometric models such as Partial Least Square (PLS) and Principle Component Regression Analysis (PCA) relate the multiple spectral intensities from numerous calibration samples to the recognized analytes. This study focused on the FT-IR calibration and quantification of heavy metals (Ag, Cd, Cu, Pb and Zn) in surveyed water sources. FT-IR measurements were compared with the atomic absorption spectrometer (AAS) measurements. Quantitative analysis methods, PCA and PLS, were used in the FT-IR calibration. The spectral analyses were done using the Attenuated Total Reflectance (ATR-FTIR) technique on three river and four borehole water sources sampled within two seasons in QwaQwa, South Africa (SA). The PLS models had good R2 values ranging from 0.95 to 1 and the PCA models ranged from 0.98 to 0.99. Significant differences were seen at 0.001 and 0.05 levels between the PLS and PCA models for detecting Cd and Pb in the water samples. The PCA models detected Ag concentrations more (˂0 mg L−1 on selected sites). Both the PLS and PCA models had lower detection only for Zn ions mostly above 45 mg L−1 deviating from the AAS measurements (<0.020 mg L−1). The FT-IR spectroscopy demonstrated good potential for heavy metal determination purposes.
New AVO Attributes and Their Applications for Facies and Hydrocarbon Prediction: A Case Study from the Northern Malay Basin
Authors: Ridwan Tsara Kamilah , Hermana Maman , Lubis Luluan Almanna , Riyadi Zaky Ahmad
Published: November 2020

Amplitude versus offset (AVO) analysis integration to well log analysis is considered one of the advanced techniques to improve the understanding of facies and fluid analysis. Generating AVO attributes are one solution to give an accurate result in facies and fluid characterization. This study is focused on a field of Northern Malay basin, which is associated with a fluvial-deltaic environment, where this system has high heterogeneity, whether it is vertically or horizontally. This research is aimed to demonstrate an application of the scale of quality factor of P-wave (SQp) and the scale of quality factor of S-wave (SQs) AVO attributes for facies and fluid types separation in field scale. These methods are supposed to be more sensitive to predict the hydrocarbons and give less ambiguity. SQp and SQs are the new AVO attributes, which derived from AVO analysis and created according to the intercept product (A) and gradient (B). These new attributes have also been compared to the common method, which is the Scaled Poisson’s Ratio attribute. By comparing with the Scaled Poisson’s Ratio attribute, SQp and SQs attributes are more accurate in determining facies and hydrocarbon. SQp and SQs AVO attributes are integrated with well log data and considered as the best technique to determine facies and fluid distribution. They are interpreted by using angle-stack seismic data based on amplitude contrast on interfaces. Well log data, e.g., density and sonic logs, are used to generate synthetic seismogram and well tie requirements. The volume of shale, volume of coal, porosity, and water saturation logs are used to identify facies and fluid in well log scale. This analysis includes AVO gradient analysis and AVO cross plot to identify the fluid class. Gassmann’s fluid substitution modeling is also generated in the well logs and AVO synthetics for in situ, pure brine, and pure gas cases. The application of the SQp and SQs attributes successfully interpreted facies and fluids distributions in the Northern Malay Basin.
Readapting Pandemic Premediation and Propaganda: Soderbergh’s Contagion amid COVID-19
Authors: Moore Kevin C.
Published: November 2020

Steven Soderbergh’s pandemic thriller Contagion (2011) was trending strongly on streaming services in the US in the early days of COVID-19 restrictions, where the fiction took on an unforeseen afterlife amid a real pandemic. In this new context, many viewers and critics reported that the film seemed “uncanny,” if not prophetic. Frameworks such as Priscilla Wald’s notion of the “outbreak narrative,” as well Richard Grusin’s “premediation,” may help to theorize this affective experience on the part of viewers. Yet the film was also designed as a public health propaganda film to make people fear and better prepare for pandemics, and the present account works to recover this history. Although the film takes liberties with reality, in particular by proposing an unlikely vaccine-development narrative, Soderbergh and screenwriter Scott Z. Burns consulted prominent scientists and policymakers as they wrote the film, in particular Larry Brilliant and Ian Lipkin. These same scientists were consulted again in March 2020, when an effort spearheaded by Columbia University’s Mailman School of Public health reunited the star-studded cast of Contagion, who created at home a series of public health announcement videos that might be thought of as a kind of re-adaptation of the film for the COVID-19 era. These public service announcements touch on key aspects of pandemic experience premediated by the original film, such as social distancing and vaccine development. Yet their very production as “work-from-home” illustrates how the film neglected to address the status of work during a pandemic. Recovering this history via Contagion allows us to rethink the film as a cultural placeholder marking a shift from post-9/11 security politics to the pandemic moment. It also becomes possible to map the cultural meaning of the technologies and practices that have facilitated the pandemic, which shape a new social order dictated by the fears and desires of an emerging work-from-home class.
A Numerical Study of Effects of Radiation on Deep Convective Warm Based Cumulus Cloud Development with a 3-D Radiative Transfer Model
Authors: Zhang Tianyu , Sun Jiming , Yang Yi
Published: November 2020

The effects of radiation heating and cooling on cumulus cloud development have been the focus of considerable attention for many years. However, it is still not clear how radiation impacts cloud droplet growth. Since cloud inhomogeneity has a great influence on radiation transmission, we coupled the 3D atmospheric radiative transfer model using the spherical harmonic discrete ordinate method with WRF-LES, which can improve the simulation accuracy of the inhomogeneous effect of clouds on radiation compared with that of the 1D radiation method. The shortwave and longwave radiation fluxes for upward and downward directions were simulated with different solar zenith angles. The comparison of 1D and 3D radiative solvers for deep convective cloud cases shows that the 3D radiative solver provides an accurate structure of solar and thermal radiation characteristics and the spatial distribution field. The solar radiation heating is likely to increase perpendicular to the solar incidence direction. For longwave radiation, the cooling effect on the cloud top and the heating effect on the cloud base are both more intense in the 3D radiation model. This study focuses on 3D cloud-radiative interactions in an inhomogeneous cloud field in a large eddy simulation, and the results suggest that compared with the widely used 1D radiative solver in WRF, the 3D radiation model can provide a precise description of the radiation field in an inhomogeneous atmosphere.
Development of a Method to Determine the Fractional Deposition Efficiency of Full-Scale HVAC and HEPA Filter Cassettes for Nanoparticles ≥3.5 nm
Authors: Todea Ana Maria , Schmidt Frank , Schuldt Tobias , Asbach Christof
Published: November 2020

Novel methods have been developed to measure the fractional deposition efficiency for nanoparticles of full-scale HVAC and HEPA filter cassettes down to a particle size of 3.5 nm. The methods use a flame spray nanoparticle generator to produce NaCl test aerosols with narrow size distributions and very high concentrations. While the efficiency curves of lower efficiency filters of classes F7 and E10 were still able to be determined by measuring the size distributions of the polydisperse test aerosols upstream and downstream of the filter, two new testing procedures were developed for high efficiency filters of class H13. One considers the narrow size distributions of the test aerosols as quasi-monodisperse and follows a similar approach like EN 1822 for flat sheet media. The second one evaluates mobility classified fractions of the quasi-monodisperse test aerosols. A dedicated multiple charge correction scheme was developed to account for the effect of multiply charged particles. While the latter procedure allows to extend the particle size range, the prior significantly reduces the measurement time. All tests delivered meaningful results, which were very comparable with the results from flat sheet media tests.
Summer Westerly Jet in Northern Hemisphere during the Mid-Holocene: A Multi-Model Study
Authors: Xu Chuchu , Yan Mi , Ning Liang , Liu Jian
Published: November 2020

The upper-level jet stream, a narrow band of maximum wind speed in the mid-latitude westerlies, exerts a considerable influence on the global climate by modulating the transport and distribution of momentum, heat and moisture. In this study by using four high-resolution models in the Paleoclimate Modelling Intercomparison Project phase 3, the changes of position and intensity of the northern hemisphere westerly jet at 200 hPa in summer during the mid-Holocene (MH), as well as the related mechanisms, are investigated. The four models show similar performance on the westerly jet. At the hemispheric scale, the simulated westerly jet has a poleward shift during the MH compared to the preindustrial period. The warming in arctic and cooling in the tropics during the MH are caused by the orbital changes of the earth and the precipitation changes, and it could lead to the weakened meridional temperature gradient and pressure gradient, which might account for the poleward shift of the westerly jet from the thermodynamic perspective. From the dynamic perspective, two maximum centers of eddy kinetic energy are simulated over the North Pacific and North Atlantic with the north deviation, which could cause the northward movement of the westerly jet. The weakening of the jet stream is associated with the change of the Hadley cell and the meridional temperature gradient. The largest weakening is over the Pacific Ocean where both the dynamic and the thermodynamic processes have weakening effects. The smallest weakening is over the Atlantic Ocean, and it is induced by the offset effects of dynamic processes and thermodynamic processes. The weakening over the Eurasia is mainly caused by the dynamic processes.