bluuebunny/crossref_metadata_2025 huggingface dataset:
Epidemiology of atlas fractures in the United States
Authors: Lyons Joseph Gabriel , Mian Humza Moghis
Published: March 2022

Introduction:

Fractures of the atlas represent a large portion of cervical spine trauma in the geriatric population. With an aging and more active population, it is expected that the number of patients sustaining atlas fractures is increasing. However, epidemiologic data regarding the incidence of atlas fractures in large populations are scarce. The aim of this study was to investigate the incidence and demographic characteristics of patients with fractures of the atlas in the United States (US) over the last 20 years.

Materials and Methods:

This descriptive epidemiology study retrospectively analyzed the National Electronic Injury Surveillance System database to identify cases of atlas fractures presenting to US Emergency Departments (EDs) from 2001 to 2020. Annual and overall numbers of fractures and fracture incidence rates, patient demographics (age, gender, race), and injury characteristics (mechanism, associated injuries) were analyzed. Incidence rates are expressed as the number of fractures per million at-risk person-years. Patients were split into four different age groups for comparisons (<18, 18–64, 65–79, 80+ years).

Results:

An estimated 38,092 cases of acute atlas fractures were identified, representing 11.1% of all cervical fractures and corresponding to an overall incidence rate of 6.2. Slightly more than half (54%) occurred in females and the mean age was 71 years. Overall, a majority (64%) of cases occurred in patients > 70 years old. There was substantial increase in incidence rate with age (<18 years: 0.7; 18–64 years: 2.6; 65–79 years: 17.1; 80 + years: 71.8). The most common injury mechanism was a low-energy fall (74%). Overall, only 42% of atlas fractures were isolated injuries, with 58% of patients sustaining at least one concomitant injury and 48% sustaining at least one additional fracture. Accounting for population growth yielded a significantly increasing incidence over the study period from 1.7 in 2001 to 13.4 in 2020 (annual percent increase = 11, P < 0.00001). Disproportionately large increases in incidence rates were observed in the oldest patient groups.

Conclusions:

Atlas fractures occur in older patients and are often associated with concomitant injuries to the head and spine. These types of fractures are increasing in the US, especially among the elderly. The annual incidence increased nearly 700% over the course of the study period and in 2020 was over 13 per million overall. In elderly patients >80 years old, the most recent annual incidence rate was over 157 per million.
Vertebral artery dissection in acute cervical spine trauma
Authors: Gupta Rahul , Siroya Hardik Lalit , Bhat Dhananjaya Ishwar , Shukla Dhaval P , Pruthi Nupur , Devi Bhagavatula Indira
Published: March 2022

Objective:

The aim of this study was to study mechanism, risk factors, and prognosis of patients with vertebral artery dissection (VAD) from acute cervical spine trauma (CST).

Methods:

A total of 149 consecutive patients were chosen from 2014 to 2019 from our institute data base, and their records were retrospectively studied. Morphology of fracture and subluxation were studied in detail with respect to the presence or absence of VAD.

Results:

Patients were divided in subsets of axial spine injury and subaxial spine injury. Subgroup and group analysis was performed and computerized tomography angiogram, MR angiogram and T1/T2 axial scans were studied to identify VAD, an incidence of 14.1% was found. Patients having infarcts in posterior circulation were also identified.

Conclusion:

There is a significant contribution of biomechanics of CST and evolution of VAD. This is an important consideration to prevent significant morbidity and mortality. Hence, a diagnostic algorithm which can be applied in any hospital setup is the need of the hour.
Do the newly proposed realignment targets bridge the gap between radiographic and clinical success in adult cervical deformity corrective surgery
Authors: Pierce Katherine E. , Krol Oscar , Lebovic Jordan , Kummer Nicholas , Passfall Lara , Ahmad Waleed , Naessig Sara , Diebo Bassel , Passias Peter Gust
Published: March 2022

Hypothesis:

The myelopathy-based cervical deformity (CD) thresholds will associate with patient-reported outcomes and complications.

Materials and Methods:

This study include CD patients (C2-C7 Cobb > 10°, CL > 10°, cervical sagittal vertical axis > 4 cm, or CBVA > 25°) with BL and 1-year (1Y) data. Modifiers assessed low (L), moderate (M), and severe (S) deformity: CL (L: >3°; M:-21° to 3°; S: <[FIGURE DASH]21°), TS-CL (L: <26°; M: 26° to 45°; S: >45°), C2-T3 angle (L: >[FIGURE DASH]25°; M:-35° to-25°; S: <[FIGURE DASH]35°), C2 slope (L: <33°; M: 33° to 49°; S: >49°), MGS (L: >[FIGURE DASH]9° and < 0°; M: [FIGURE DASH]12° to [FIGURE DASH]9° or 0° to 19°; S: < [FIGURE DASH]12° or > 19°), and frailty (L: <0.18; M: 0.18–0.27, S: >0.27). Means comparison and ANOVA assessed outcomes in the severity groups at BL at 1Y. Correlations found between modifiers assessed the internal relationship.

Results:

One hundred and four patients were included in the study (57.1 years, 50%, 29.3 kg/m2). Baseline S TS-CL, C2-T3, and C2S modifiers were associated with increased reoperations (P < 0.01), while S MGS, CL, and C2-T3 had increased estimated blood lost (>1000ccs, P < 0.001). S MGS and C2-T3 had more postop DJK (60%, P = 0.018). Improvement in TS-CL, C2S, C2-T3, and CL patients had better numeric rating scale (NRS) back (<5) and EuroQOL 5-Dimension questionnaire (EQ5D) at 1 year (P < 0.05). Improving the modifiers correlated strongly with each other (0.213–0.785, P < 0.001). Worsened TS-CL had increased NRS back scores at 1 year (9, P = 0.042). Worsened CL had increased 1-year modified Japanese Orthopedic Association (mJOA) (7, P = 0.001). Worsened C2-T3 had worse NRS neck scores at 1 year (P = 0.048). Improvement in all six modifiers (8.7%) had significantly better health-related quality of life (HRQL) scores at follow-up (EQ5D, NRS, and Neck Disability Index).

Conclusions:

Newly proposed CD modifiers based on mJOA were closely associated with outcomes. Improvement and deterioration in the modifiers significantly impacted the HRQL.
Saradhi’s single stage, anterior sequential reduction utilizing C3 for type III hangman’s fracture
Authors: Mudumba Vijaya Saradhi , Pavan S. , Alugolu Rajesh
Published: March 2022

Background:

Levine Edward's Type III Hangman's fractures are highly unstable and in absence of level 1 evidence, the treatment is individualized. A longer cantilever beam can achieve not just reduction of highly displaced fragments but can also provide a stable construct without the need of global instrumentation.

Objective:

We extrapolated the surgical techniques of the long cantilever beam to this rare group of cohorts for anterior alone, sequential reduction utilizing C3 rather than sacrificing in a single sitting and single approach.

Materials and Methods:

This is a prospective observational study from 2015 to 2019, of all consecutive 10 patients diagnosed and treated as Type III Hangman's fracture in the Department of Neurosurgery. Clinical evaluation and pain scores were recorded in the preoperative assessment. Radiological investigations included plain roentgenograms in anterior-posterior and lateral views, magnetic resonance imaging, and computed tomography scan of the cervical spine. Preoperative cervical traction was placed in all cases for the achievement of facetal reduction. The high cervical extra-pharyngeal approach was utilized for discectomy, bone grafting, reduction, and sequential plating.

Results:

Complete reduction was achieved in all the cases and none required additional posterior surgery. There was a significant decrease in axial neck pain with complete fusion of the graft, and healing of fracture site.

Conclusion:

The anterior alone approach with a longer cantilever for primary internal stabilization is a technically safe and suitable option for unstable Type III Hangman's fracture.
Spontaneous spinal epidural hematoma
Authors: Diyora Batuk , Chajjed Rahul , Dhall Gagan
Published: March 2022

Background:

Spontaneous Spinal Epidural Haematoma (SSEH) is a rare entity that results from spontaneous, non-traumatic haemorrhage in the spinal epidural space. While erring on the side of caution, few significant clues in the history can lead to an earlier differentiation from more frequently seen pathologies like acute disc herniation and spinal tumors. Once diagnosed, the decision of surgical versus conservative management is entirely clinical and situation-based. In ambiguous scenarios, the study of specific parameters can help to choose one over another.

Objective:

We are sharing here our experience of six such patients and review relevant literature, mainly focusing on the variables that can help to determine the best therapeutic plan.

Material and Methods:

We studied the parameters like age, gender, location, number of levels involved, drug history, duration to surgery, American Spinal Injury Association (ASIA) impairment scale grade at presentation, therapeutic plan, and their final ASIA score for six patients of SSEH who presented to our department. We also reviewed the published literature focusing on therapeutic decision-making in SSEH.

Results:

Five patients were managed surgically and one conservatively. Variables considered while opting for surgical treatment. One patient was managed conservatively based on his improving neurology.

Conclusions:

Patients with SSEH need to be cautiously selected for surgical or conservative management for their optimal outcome. The study's various variables highlight a few critical concerns while predicting the outcome and guide one to decide a therapeutic plan for this rare pathology.
A case of mobile intradural paraganglioma in the lumbar spine
Authors: Muthiah Shanmugam , Sivaramamoorthy Vijaykumar , Pradipta Rath Kumar , Easwaran Ramakrishna
Published: March 2022

Mobile intradural extramedullary tumor is a rare entity with only 26 cases reported in the English literature. There is no case report of spinal paraganglioma migrating spontaneously and causing the acute neurological deficit, to the best of our knowledge. We present the first case report of a mobile spinal paraganglioma and review the literature.
Sympathetic conjoined lumbosacral nerve root in kambin's triangle during transforaminal endoscopy
Authors: Patgaonkar Prasad , Dhole Kiran , Goyal Vaibhav , Marathe Nandan
Published: March 2022

Kambin's triangle is a safe corridor for transforaminal endoscopic approach as it is devoid of any neurovascular structure. We came across an interesting case where we encountered a large conjoined lumbosacral nerve root (CNR) in Kambin's triangle during transforaminal endoscopic spine surgery. Patient had intraoperative sympathetic shock which recovered after administering atropine. A 50-year-old female presented with low back pain with bilateral lower limb radiculopathy for 3 years. Magnetic resonance imaging revealed left L4-5 foraminal annular fissure. Radiculopathy was in L5 dermatomal pattern which was confirmed by diagnostic discography and lateral recess block. Left-sided L4-5 transforaminal endoscopic lumbar discectomy was done where we encountered a large CNR in safe zone of Kambin's triangle. Transforaminal endoscopic spine surgery done under monitored anesthesia care with patient in awake and aware state allows identification, diagnosis, and prevention of injury to anomalous neural structure in Kambin's triangle to avoid incidence of failed back syndrome.
Familial chiari malformation
Authors: Kesavapisharady Krishnakumar , Jamaluddin Amjad Mohammed , Kamrudeen Adam , George Tobin , Divakar Ganesh
Published: March 2022

Chiari malformation type 1 (CM 1) is defined asherniation ofcerebellar tonsils 4-5 mm below the foramen magnum. Multiple developmental factors like defective development of pontine flexure and shallow posterior fossa are the proposed factors which predispose the development of this syndrome. These reports on familial occurrence of this syndrome correlates with the embryonal- developmental etiology of Chiari 1 malformation. Recent advances in the understanding of the influence of genes and pathogenesis of familial Chiari malformation are expected to improve management of affected patients and monitoring of at-risk family members.
Address the cause, not the effect
Authors: Salunke Pravin
Published: March 2022

The C1-2 joints in cases of congenital atlantoaxial dislocation are often oblique in both sagittal and coronal planes giving rise to anteroposterior and vertical slip of C1 over C2. Asymmetry on either side gives rise to coronal/lateral angular tilt along with rotational component. The dislocation is a dynamic process though it may appear to be fixed. The compressing dens is effect of dislocation and not the cause. The treatment should be directed towards C1-2 joint manipulation that would realign the joints as well as the dens. The facetal osteotomies coupled with manipulation for realignment in all planes provides a composite solution for even the complex lateral dislocation or complete spondyloptosis with severely deformed C1–2 joints, obviating the need for transoral decompression.
Accuracy and safety of free-hand pedicle screw placement in cervical injury patients
Authors: Rijal Sanjeeb , Dhatt Sarvdeep Singh , Kumar Vishal , Neradi Deepak , Prakash Mahesh
Published: March 2022

Objectives:

The purpose of this study was to describe the free hand method of pedicle screw placement without intraoperative imaging monitors and to evaluate the accuracy of the screw placement in quadriplegics patients.

Methods:

A free hand screw was inserted in the eleven cervical injury patients with quadriplegia. We studied the preoperative pedicle dimension in all the patients and assessed the clinical and radiological outcome and accuracy of the screw placement.

Results:

A total of 44 screws were inserted in the cervical pedicles of eleven patients. The postoperative images showed that 28 of the 44 screws had perforated the pedicles but none of them had breached the spinal canal. Among them 16 screws were grade 2 and 12 screws were grade 3. All the screws had penetrated the lateral wall. There were no neurovascular complications related to any malpositioned screw and there was no screw loosening or instrumentation failure in the patients.

Conclusion:

The free hand screw placement without intraoperative image guidance seems to be safe and effective method of fixation. But this technique requires sound knowledge of the cervical anatomy and experience and is useful in the places where navigation system are not available.
Spinal intramedullary ependymoma presenting with atypical facial pain
Authors: Diyora Batuk , Patel Mehool , Bhende Bhagyashri , Dhall Gagan , Vekariya Mayank A , Mulla Mazharkhan
Published: March 2022

Spinal cord ependymomas are the most common neuroepithelial tumors in adults accounting for two-third of all spinal gliomas. Although most patients with spinal cord tumors present with typical symptoms, the presence of a nonspecific clinical presentation with low clinical suspicion results in delayed diagnosis. We report a case of spinal intramedullary ependymoma in a 39-year-old man who presented with atypical pain over the lower half of the right side of the face for 3 months. Magnetic resonance imaging revealed a high cervical intramedullary contrast-enhancing solid mass lesion. The lesion was excised via cervical laminectomy. Histopathological examination confirmed the presence of an ependymoma. Complete resolution of facial pain was achieved postsurgery. At 2 years of follow-up, there was no evidence of clinical or radiological recurrence. Atypical facial pain can be the presenting feature of spinal intramedullary ependymoma. Complete relief of facial symptoms can be achieved by microsurgical excision.
Efficacy of Customized Soft Occlusal Splints in the Management of Temporomandibular Joint Disorders among the Population of Parsa District of Nepal
Authors: Wazir Sartaj Singh , Jaiswal Alok Kumar , Srivastava Rahul
Published: March 2022

Background:

In recent years, temporomandibular joint disorders (TMDs) have been a highly debated topic. TMD is the collective term of clinical problems that involves the masticatory apparatus, temporomandibular joint (TMJ), and its associated structures or both. It is really a tough challenge for both the dental and the medical specialists and is often difficult to diagnose and treat such a disorder as the presenting symptoms can be variable. A variety of treatment modalities have been described in the literature for its management and the conservative method is most preferred. The objective of the present study was to evaluate the effectiveness of soft occlusal splint therapy among the population of Parsa district of Nepal in the management of TMDs.

Materials and Methods:

Thirty subjects with signs and symptoms of TMDs were included in the study, out of which 13 (43.3%) subjects were males and 17 (56.7%) were females, with age ranging from 21 to 40 years. Soft occlusal splints were given to the patients for about 3 months and evaluated for reduced mouth opening, tenderness of TMJ (preauricular), TMJ sounds, and mandibular deviation after 1 week of initiation of therapy and every month for 3 consecutive months.

Results:

There was a significant improvement of 3.06 mm (9.7%) in mouth opening, 86.7% of subjects showed significant reduction in preauricular tenderness, 80.0% subjects showed reduction in TMJ sounds, and 76.7% of subjects showed improvement in mandibular deviation after 3 months of the splint therapy. Paired t-test and Chi-square tests were done for comparison.

Conclusions:

Soft occlusal splints can be used effectively as a conservative treatment modality in reducing the signs and symptoms related to TMDs.
Propranolol use in patients with cirrhosis and refractory ascites
Authors: Chen Yen-Chun , Li Yun-Da , Lu Chia-Ming , Huang Wei-Chun , Kao Sung-Shuo , Chen Wen-Chi
Published: March 2022

Background:

The impact of propranolol on patients with cirrhosis and refractory ascites is controversial. We conducted a nationwide longitudinal cohort study to compare the survival between patients with cirrhosis and refractory ascites, with and without using propranolol.

Methods:

Data of patients with cirrhosis and refractory ascites using propranolol, and controls matched by age and gender, were extracted from The National Health Insurance Research Database of Taiwan. The baseline demographic characteristics were compared between groups. Cox regression analysis was used to examine the predictors of mortality.

Results:

In this study, 1788 patients were enrolled in each group; 1304 patients (72.9%) in the propranolol group and 1445 patients (80.8%) in the control group died (P < 0.001). The mean survival was 34.3 ± 31.2 months in the propranolol group and 20.8 ± 26.6 months in the control group (P < 0.001). Propranolol (hazard ratio [HR]: 0.60, 95% confidence interval [CI]: 0.55–0.64, P < 0.001), statins (HR: 0.43, 95% CI: 0.34–0.56, P < 0.001), age (HR: 1.02, 95% CI: 1.01–1.02, P < 0.001), and diabetes mellitus (HR: 1.14, 95% CI: 1.05–1.24, P = 0.002) were the independent predictors for mortality.

Conclusions:

Use of propanolol was associated with reduced mortality, compared with controls, in this nationwide cohort of patients with cirrhosis and refractory ascites.
Optimal linearization of vector fields on the torus in non-analytic Gevrey classes
Authors: Bounemoura Abed
Published: March 2022

We study linear and non-linear small divisors problems in analytic and non-analytic regularity.
We observe that the Bruno arithmetic condition, which is usually attached to non-linear
analytic problems, can also be characterized as the optimal condition to solve the linear problem
in some fixed non-quasi-analytic class. Based on this observation, it is natural to conjecture that
the optimal arithmetic condition for the linear problem is also optimal for non-linear small divisors
problems in any reasonable non-quasi-analytic classes. Our main result proves this conjecture in
a representative non-linear problem, which is the linearization of vector fields on the torus, in the
most natural non-quasi-analytic class, which is the Gevrey class. The proof follows Moser’s argument
of approximation by analytic functions, and uses works of Popov, Rüssmann and Pöschel in
an essential way.
Regularity of the optimal sets for the second Dirichlet eigenvalue
Authors: Mazzoleni Dario , Trey Baptiste , Velichkov Bozhidar
Published: March 2022

This paper is dedicated to the regularity of the optimal sets for the second eigenvalue of
the Dirichlet Laplacian. Precisely, we prove that if the set

\Omega

minimizes the functional

\mathcal{F}_\Lambda(\Omega) = \lambda_{2} (\Omega) + \Lambda |\Omega|

, among all subsets of a smooth bounded open set

D \subset \mathbb{R}^{d}

, where

\lambda_{2} (\Omega)

is the
second eigenvalue of the Dirichlet Laplacian on

\Omega

and

\Lambda > 0

is a fixed constant, then

\Omega

is equivalent to the union of two disjoint open sets

\Omega_{+}

and

\Omega_{-}

, which are

C^{1,\alpha}

-regular up to a (possibly empty) closed set of Hausdorff dimension at most

d - 5

, contained in the one-phase free boundaries

D \cap \partial\Omega_{+}

\backslash

\partial\Omega_{-}

and

D \cap \partial\Omega_{-}

\backslash

\partial\Omega_{+}

.
Fully nonlinear free transmission problems with nonhomogeneous degeneracies
Authors: De Filippis Cristiana
Published: March 2022

We prove existence and regularity results for free transmission problems governed by fully nonlinear elliptic equations with nonhomogeneous degeneracies.
Experimental Investigation of TIG Welding Parameters and Weld Joint Strength for Carbon Steel - SA516GR70 Material based on Taguchi Method
Authors: Amarapure Santosh S. , Patil Ratan A.
Published: March 2022

This study focuses on experimental study of mechanical characterisation for the carbon steel material SA516GR70, steel alloy welds through tungsten inert gas (TIG) welding process used for the applications of pressure vessel and heat exchanger. Current work describes the preparation of test coupons which is used for sample preparation of tensile, bending and hardness test. Welding process parameters optimization is carried out using Taguchi method for the carbon steel weld material to improve the properties. Using the orthogonal array, experiments are setup and weld joint obtained is used for mechanical testing. Graphs are obtained from the full factorial design using the Mini tab software which is helpful in studying the effects of the parameters on properties. Interpretation of the statistic for various parameters is analysed and the coefficients are determined. Main effects plot, interaction plot and residual plots are plotted which reveal that model fits the data with the average acceptance level of 91.85%.
Synthesis of Microstructure and Tribological Properties of AMMCs Fabricated by Two Different Powder Metallurgy Routes
Authors: Mahato Jayanta K. , Sameer S. , Jadon Jitender K.S. , Singh Rajkishor , Gahlaut Raman , Pramanick Akshay K.
Published: March 2022

In this investigation tribological properties of Aluminium-Alumina metal matrix composites (AMMCs) are developed through developing microstructure and improving physical properties by controlling process parameters of two different powder metallurgy routes. In one route; 5, 10 and 15 weight percent Alumina (Al2O3) powder was manually blended with pure Aluminium (Al) and compacted at 10 ton/inch2 uniform pressure followed by sintering at 400°C, 500°C and 600°C for 30 minutes. Alternately, commercially pure Al powder was oxidized at 500°C, 600°C, 700°C and 800°C for 15, 30 and 45 minutes individually followed by same powder metallurgy process as applied in the first route of AMMCs fabrication like blending, compacting and sintering. Optical micrographs of fabricated AMMCs were taken and corelated with the apparent porosity of fabricated AMMCs as well as with different process parameters and variables like sintering and oxidation temperatures, oxidation duration, and wt. % of Alumina. Tribological properties of all AMMCs were also measured and corelated with the process parameters and variables as well as with the observed microstructure and measured apparent porosity. It is observed that finer grain structures are developed by increasing sintering and oxidation temperatures, and oxidation duration. It is also observed that wear resistance of AMMCs is enhanced by increasing sintering and oxidation temperatures, oxidation duration, and wt. % of Alumina individually; whereas, more enhancement is observed in case of second route of AMMCs fabrication. Therefore, the uniqueness of this investigation is to improve the wear resistance of pure Aluminium by fabricating AMMCs through simply heating pure Al powder at different temperatures followed by powder metallurgy process instead of adding reinforcement material (Alumina powder).
Coupled Field Analysis of Hemispherical Resonator Gyroscope
Authors: Rao Venkatesh K.P. , Rai Shweta , Batish Tribhuvan , Gulati Anmol
Published: March 2022

This work deals with the electromechanical analysis of the Hemispherical Resonator Gyroscope (HRG). The HRG is a type of Coriolis vibratory gyroscope (CVG), which uses Coriolis force to measure the input angular rate. For any CVG drive and sense mode, frequencies play a critical role, which decides the sensitivity and bandwidth of a sensor. In this study, we carry out modal analysis to evaluate the natural frequencies and corresponding mode shapes of an HRG. As HRG is an electromechanical structure, the device is driven at resonance in the drive direction, and the Coriolis force leads to motion in the sense direction. In this study, we present the piezoelectric based HRG; coupled field simulations are carried out to evaluate the performance characteristics of a sensor.
Experimental Study of Multiple Jet Impingement Cooling on a Flat Plate
Authors: Murthy Niranjan , Deepak S. , Arunakumara P.C. , Patil Arun Y.
Published: March 2022

Heat transfer to a straight multiple impinging air/ water jet is studied experimentally. A 22 cm thin copper plate, 1 mm thick was electrically heated and cooled from one side. The temperature was measured on the other side. A geometrical prearrangement of 77 arrays in-line with a pitch of 3 mm was tested. The heat flux is varied from 20 to 250 W/cm2 with 0.25 and 0.5 mm diameter jets. The temperature differences between jet exits to test surface is within 700°C for air jets and 300°C for water jets. Though the jet impingement using multiple jets is a complicated heat transfer phenomenon, the results were interrelated using a relation in the mathematical form of the Nusselt number which is a function of two exponents, n and m. The exponent (n) shows the effect of Reynolds number for both air and water jets. The exponent (m) specifies the consequences of heat flux on the working fluid and diameter of jet.
Experimental Investigation on Low-Velocity Impact Strength of E-Glass/Carbon Fiber Reinforced Hybrid Polymer Composite
Authors: Prasad Manu , Ahmed Nayeem , Pasha Azeem , Manjunath A.C.
Published: March 2022

Plenty of research works has happened on the polymer matrix composite with different fiber as reinforcements from last 3 decades to satisfy aerospace, automotive, marine and military and defence industries requirements. Although, several reinforcements materials like glass fiber, carbon fiber, Kevlar fiber, etc. are used in the development of advanced materials, producing efficient and high-performance material has become a primary requirement of the industries and this had led to research and designing of hybrid composites. In this work, E glass/carbon fiber reinforced epoxy 5052 polymer matrix composite is prepared by vacuum bag moulding technique with varying the thicknesses from 2mm, 3mm to 4mm. A low-velocity impact test is conducted for the composite laminates for different impact energies. The force-time relationship is studied. The decrement in contact time and increment in peak force is noticed with an increase in the thickness of the composite laminates. Ultra-sonic scanning is also performed to understand the delamination at the damaged area.
Perception and challenges of health science students toward e-learning in a Sub-Saharan African country: a multi-institutional study
Authors: Kabare Gloria , Muthuuri Nikita , Sarna Krishan , Gwala Fidel , Amuti Thomas , Olabu Beda , Obimbo Moses , Ogeng’o Julius
Published: March 2022

Background: E-learning is important in improving access to quality health sciences education. This study aimed to determine the perspectives of Kenyan health science students toward e-learning in a bid to enhance effective learning during the COVID-19 pandemic and beyond. Methods: This descriptive cross-sectional study targeted 294 Kenyan health science students. Approval was obtained from the Kenyatta National Hospital–University of Nairobi Ethics Research Committee, and informed consent was obtained from participants. Data were collected using Google Forms and analyzed using SPSS version 27.0. A p value ≤0.05 was considered significant at 95% confidence interval. Results: Most students had good knowledge of online learning; 74.9% reported having received training on the same by their universities and 74.5% further reported to have taken tests on the same. Almost half (45.5%) were knowledgeable of the use of the internet to access materials. Most (79.6%) portrayed a positive attitude toward online learning, agreeing to its use as an integral part of learning. However, 70.2% noted a decrease in concentration and changes in reading habits (44.7%). Regarding challenges faced, unreliable internet connection (56.9%) and lack of motivation (73.7%) were common. Conclusion: The majority of the Kenyan health science students portrayed good knowledge, attitude, and practice toward e-learning amidst challenges.
Why the Problem of Evil Might not be a Problem after all in African Philosophy of Religion
Authors: Chimakonam Amara Esther
Published: March 2022

For decades, the problem of evil has occupied a centre stage in the Western philosophical discourse of the existence of God. The problem centres on the unlikelihood to reconcile the existence of an absolute and morally perfect God with the evidence of evil in the universe. This is the evidential problem of evil that has been a source of dispute among theists, atheists, agnostics, and sceptics. There seems to be no end to this dispute, making the problem of evil a perennial one in Western Philosophy of Religion. In this essay, I will contribute to this discourse from an African perspective. This essay, therefore, explores the evidential problem of evil within the African philosophy of religion. I argue that it is unlikely for the evidential problem of evil to be a problem in African philosophy of religion. I invoke an Ejima-based argument to support this claim. I conceptualize the Igbo word Ejima to metaphysically mean the inevitable coexistence of two opposite variables as complements to argue that God could be both good and evil within the African Traditional Religion, which explains why good and evil exist in the universe.
Bewaji and Fayemi On God, Omnipotence and Evil
Authors: Agada Ada
Published: March 2022

This paper explores the contradiction of positing the existence of a God who is at once omnipotent and not omnipotent in respect of his power that arises in the thought of two African philosophers of religion, John A.I. Bewaji and Ademola Kazeem Fayemi who accept the limitation thesis that projects a limited God and deny the legitimacy of the transcendence view in Yoruba and, by extension, African thought. I demonstrate in this paper that the contradiction arises from the fact that while Bewaji and Fayemi explicitly deny the legitimacy of the transcendence view in Yoruba and, by extension, African thought, they implicitly accept the view and unwittingly and illegitimately attempt to reconcile the conflicting views through the analysis of the notions of God’s creatorship, co-creatorship, and controllership. I conclude by recommending that instead of attempting to reconcile the antinomy of God’s existence in African philosophy of religion, African philosophers should acknowledge the legitimacy of the two conflicting theses constituting the antinomy and, accordingly, sustain logical consistency by strictly thinking within either the framework of limitedness or the framework of transcendence.
End Fuel Prices and Their Drivers in the Czech Republic
Authors: Tyll Ladislav , Fingl Filip
Published: March 2022

This paper deals with understanding drivers influencing the end price of fuels in the Czech Republic and ramifications for relevant companies. Its aim is to provide a comprehensive understanding of all relevant elements that have been influencing end prices of gasoline and diesel during last 8 years, understand their leverage and uncover which of those were the most important for this development. These are then researched using mainly graphical analysis and statistical tools. The delivery is that both prices of gasoline and diesel are highly correlated with the price development of crude oil and the prices of their respective commoditized barges expressed in the nominal value of CZK. It was also discovered that there are visible tendencies for asymmetrical pricing reaction and reaction lags, which could serve as a basis for a follow-up work. We also tried to examine the level in which Czech crown as a national currency provides cushion against up and down swings in commodity markets. Based on these findings several conclusive recommendations for relevant companies were built and delivered.
Review of Cases of Integrability in Dynamics of Lower- and Multidimensional Rigid Body in a Nonconservative Field of Forces
Authors: Shamolin Maxim V.
Published: March 2022

Study of the dynamics of a multidimensional solid depends on the force-field structure. As reference results, we consider the equations of motion of low-dimensional solids in the field of a medium-drag force. Then it becomes possible to generalize the dynamic part of equations to the case of the motion of a solid, which is multidimensional in a similarly constructed force field, and to obtain the full list of transcendental first integrals. The obtained results are of importance in the sense that there is a nonconservative moment in the system, whereas it is the potential force field that was used previously.
Runoff as a Stochastic Process
Authors: Vitali Giuliano
Published: March 2022

Runoff stationary critical flow is investigated as a stochastic process by means of two routing simulation models, a stream confluence, which has beens interpreted as a Marcus- Lushnikov coalescence process, and a channel splitting model, which has ben interpreted as a Markov chain over a regular tree. Despite of the expected similarity due to expection that they should be seen as one the backward of the other, the initiation and the stopping methods using in algorithms influence strongly stream size distribution.
Hall Effect on MHD Flow and Heat Transfer Over an Unsteady Stretching Permeable Surface In the Presence of Thermal Radiation and a Heat Source/sink
Authors: Shateyi S. , Marewo G.T.
Published: March 2022

This paper employs the computational iterative approach known as Spectral Local Linearization Method (SLLM) to analyze Hall effect on MHD flow and heat transfer over an unsteady stretching permeable surface in the presence of thermal radiation and heat source/sink. To demonstrate the reliability of our proposed method, we made comparison with Matlab bvp4c routine technique and excellent agreement was observed. The governing partial equations are transformed into a system of ordinary differential equations by using suitable similarity transformations. The results are obtained for velocity, temperature, skin friction and Nusselt number.
Development of Learning Variations to Improve Basic Jumping Skills and Play Approaches of Elementary School Students
Authors: Ritonga Doris Apriani , Damanik Suryadi , Damanik Saipul Ambri , Suprayitno Suprayitno , Priyambada Galih
Published: March 2022

From the class of 2018 to 2020, researchers found several weaknesses faced by physical education (PE) teachers in elementary schools in developing active learning. One of the very basic weaknesses is the low creativity and innovation of teachers in developing basic movement skills and character values with a play approach, and in this case, playing is made in the form of games that suit the needs of students. Teachers tend to use existing forms of play such as baseball, soccer, volleyball, and basketball, even though these games are not compatible with elementary school children's growth and development level. The purpose of research and development of learning variations of PE in sports and health based on a play approach is expected to develop basic movement abilities and character values of elementary school students. The research method used is Borg and Gall's research and development. The subjects of this study were 4th-grade elementary school students and four teachers at UPT Percut Sei Tuan. The research instrument uses a rating scale so that the variation of PE learning based on the play approach is suitable for improving elementary school students' basic techniques and character values .
Effectiveness of Sensor-Based Media to Improve Referee Education
Authors: Kasih Indra , Faridah Eva , Siregar Samsuddin , Bangun Sabaruddin Yunis , Sinulingga Albadi
Published: March 2022

The purpose of this research is to produce a new product in the form of censorship media and video assistant referee (VAR) in assisting referee leadership in a championship to achieve fair play. This research uses the Research and Development (RD) method from Sugiyono using ten steps. The place of research was carried out at the All-Indonesian Volleyball Association, Deli Serdang Regency. The population and sample in this study were 36 Deli Serdang Regency volleyball players with a small sample of 6 people, a large sample of 16, and a comparison sample of 14. For the referee sample, six nationally licensed and nine regional licensed referees. The results of this study include Net and VAR sensors used to develop a player error detection tool when smashing and blocking. The results are obtained from the data from expert validation, including: (1) Material experts 92.3% with the "Very Eligible" category. (2) Media Experts 92.5% with the "Very Eligible" category. In large-scale trials on referees and athletes, the resulting percentages were 90.8% and 92.7%, respectively, while in the comparison trial, the percentage produced was 92.5%.
Effect of Surface Modification on the Characteristics of Sisal Fiber Reinforced Concrete Treated with Na2CO3
Authors: Abirami R. , Sangeetha S. P.
Published: March 2022

Concrete with fiber as a reinforcing material is one of the important fields of research that is gaining traction in this upcoming green technology revolution. By adding fibers to concrete, the tensile strength properties are vastly improved without compromising the strength characteristics, and cost fluctuation is minimal. This research is being carried out to improve the qualities of concrete that have been infused with chemically treated sisal fiber in varied ratios. The paper investigates and describes the effects of sisal fiber when it is chemically treated and infused with concrete, comparing it to ordinary concrete in strength tests. Water absorption, workability, and other material characteristics of Sisal fiber reinforced concrete with 0.5 per cent, 1 per cent, 1.5 per cent, and 2 per cent fiber replacing cement by volume fraction and a sisal fiber aspect ratio of 1:100 are compared to the traditional M30 concrete grade. After being treated with an alkaline solution, 0.5 per cent and 1 per cent sisal fiber reinforced concrete increased tensile and compressive strength, as well as the formation of calcium carbonate deposits on the fiber interfaces; this also contributes to the concrete’s corrosion resistance and durability.
Study of Water Quality Pollution Index, Land-Use and Socio-Economic Factors in Yingkou Irrigation District of China Based on Redundancy Analysis
Authors: He Ji , Hou Xiao-Ling , Wang Wen-chuan
Published: March 2022

Water quality in irrigation areas is related to food security and many other national strategies. This study takes China’s Yingkou Irrigation District as the research object and analyzes 4 water quality indicators, including NH4+-N, TP, DO and COD, from 2017 to 2019 at 3 water quality monitoring points set up in the irrigation area. Simultaneously, a comprehensive pollution index is introduced to evaluate the quality of returned water in the irrigation area. Using Redundancy Analysis (RDA), the correlation between water quality indicators and Land-use and socio-economic indicators are analyzed separately. The results show that the water quality of the Yingkou Irrigation District varies greatly within and between years, and the months with poor water quality are concentrated in autumn and winter. This is mainly related to the geographical location of the irrigation area and the drainage cycle of rice planting. The quality of receding water shows a positive correlation with the water area and a negative correlation with the unused land. The RDA analysis with socio-economic indicators shows that PD and IP are the ones that have a more significant impact on the quality of return water in irrigation areas. The prevention and control of industrial point source pollution, as well as the interception of non-point source pollution in water regions, should be the focus of water pollution prevention and control in irrigation areas.
Pollution Characteristics of Surface Sediments in Luhun Drinking Water Reservoir in the Middle China
Authors: Zhou Zizhen , Xu Yu , Dai Zhen
Published: March 2022

The pollution status of surface sediments in the Luhun drinking water reservoir in the central of China was analyzed and evaluated, and three sampling points were selected for this study. The results showed that the organic matter content of the Luhun reservoir was as high as 5.2%, which was at a high level. The analysis of nitrogen, phosphorus, and their components showed that the total nitrogen (TN) and total phosphorus (TP) pollution in Luhun reservoir was in the medium pollution level, among which the ion-exchange state of nitrogen component and the strong-alkali extraction state of phosphorus component accounted for a relatively high risk of release into the overlying water. The results showed that the bioavailability index of Pb and Cr was as high as 0.73 and 0.62, which was of big pollution risk. Generally speaking, the sediment of Luhun reservoir had a high risk of pollution to the overlying water. The results of this study can provide a theoretical basis for urban safe water supply and provide support for water quality improvement.
PM2.5 Concentration Prediction Based on Pollutant Pattern Recognition Using PCA-clustering Method and CS Algorithm Optimized SVR
Authors: Liu Wei , Chen Fuji , Chen Yihui
Published: March 2022

Environmental issues, particularly air pollution, are a matter of concern for people all around the world. PM2.5 levels that are too high harm people’s physical and mental health. For government air pollution control, more accurate PM2.5 concentration predictions are critical. In this paper, we explored the relationship between pollutants (PM10, SO2, NO2, O3, CO) and meteorological factors (atmospheric pressure, relative humidity, air temperature, wind speed, wind direction, cumulative precipitation) that affect the generation and transmission of PM2.5. To better predict the concentration of PM2.5, we innovatively combined principal component analysis (PCA) and clustering methods to extract pollutant variables and patterns as important PM2.5 concentration predictors of different models such as support vector regression (SVR), multivariate nonlinear regression (MNR), and artificial neural network (ANN). Compared to MNR and ANN models, SVR presented better prediction accuracy. Moreover, cuckoo search (CS), cross-validation (CV), and particle swarm optimization (PSO) algorithms were used to further optimize the parameters in the process of SVR. And to evaluate the above PM2.5 concentration prediction results, we introduced several evaluating indicators including root mean squared error (RMSE), mean absolute error (MAE), mean absolute percentage error (MAPE), and person correlation coefficient (R) between predicted and measured values. The obtained results confirmed that when the pollutant data was divided into three patterns, the best prediction accuracy was achieved by the CS-SVR model.
Cryptocurrency – The Next Big Thing
Authors: Prasanna Kumar G
Published: March 2022

The cryptocurrencies are a hot topic in the global financial system. Cryptocurrency is a digital or virtual or internet currency that uses cryptography for security. Cryptocurrency has created unmatched changes in the financial market having both positive and negative contributions. The concept of cryptocurrency is a little hard to accept, but it is easy to use. It is considered difficult because it is entirely different from our conventional currencies that we people are using since ages. Here, we focus the different types of cryptocurrencies, origin and evolution of the term. The role of cryptography in early cryptocurrencies, Issues currently associated with the term, the role of cryptography in today’s cryptocurrencies, cryptocurrencies exchanges, Cryptocurrencies Trading, advantages and disadvantages of cryptocurrencies trading, How Many cryptocurrencies are there? Market Capitalization of Cryptocurrency, the 2021 Global Crypto Adoption Index Top 20, One Year change in the value of Crypto Assets.
Evolución temporal de humedales de la región ayacucho, mediante imágenes modis periodo 2002 – 2013
Authors: Rodriguez Jorge Luis Lozano , Fun Juan Carlos Chang Chang , Cruz Oscar Enrique Tang , Tarmeño Eusebio Idelmo Cisneros , Gutierrez Hernán Oscar Cortez , Gutierrez Milton Milciades Cortez
Published: March 2022

La presente investigación responde a la necesidad de caracterizar la evolución temporal de los humedales mediante imágenes satelitales, su procesamiento, análisis, interpretación y discusión, pues los cambios climáticos hacen necesario tener en cuenta que son ecosistemas importantes de gran interés por las diferentes funciones que realizan. Las imágenes satelitales del satélite TERRA del sensor AQUA, fueron procesadas con el software ENVI y se determinó el parámetro del Índice de Vegetación de Diferencia Normalizada (NDVI), más el uso del Google Earth nos permitió a grandes rasgos discriminar entre zonas de vegetación, suelo desnudo, agua y la variación en el tiempo de los Humedales de la Región de Ayacucho. La teledetección nos ofrece grandes progresos en el conocimiento de la naturaleza, aunque es necesario un mayor rigor científico en la interpretación de los resultados y tener como objetivo eliminar los efectos ocasionados por la variabilidad en las condiciones de captación, distorsión provocada por la atmósfera, y la influencia de parámetros radiométricos geométricos tales como la radiancia, reflectancia, emisividad, posición del Sol, pendiente, y altitud. Por lo cual esperamos que contribuya al conocimiento de datos importantes quedando pendiente estimar otros parámetros como la humedad de suelos, evaporación, etc. a través de la cual se precisará y reorientar la tecnología propuesta.