bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Vinyl-Terminated Silicone Oil Chain Length and Reinforcing Agent on the Properties of Silicone Rubber
Authors: Pan Hong Wei , Zang Chong Guang , Zhang Yu Long
Published: January 2022

To solve the problems of low strength and high viscosity of room temperature vulcanized liquid silicone rubber, a series of terminated vinyl silicone oil were designed and synthesized, and low viscosity and high strength silicone rubber were prepared by the mechanical reinforcing agent. the results show that the molecular structure of the vinyl-terminated silicone oil has a significant effect on the mechanical properties and viscosity of the silicone rubber, and the best performance is found when the content of vinyl-terminated silicone oil is 0.16%. The low viscosity and high strength silicone rubber prepared from it was reinforced by vinyl MQ resin and fumed silica, which had a significant effect on improving the performance. Its tensile strength increased to 5.03 MPa, elongation at break to 338.90%, and tear strength to 7.15 kN/m compared to conventional silicone rubber, while the hardness increased to 43°. The viscosity is 34.9 Pa•s. The compression modulus is 7.48 MPa.
Decomposition Kinetics and Cook-Off Numerical Simulation of Insensitive Energetic Plasticizer Plasticized Propellants
Authors: Wang Ya Lun , Chen Yu , Liu Yun Fei
Published: January 2022

Aiming at the thermal safety issues between the insensitive energetic plasticizer and propellant components, NG/BTTN and insensitive energetic plasticizer BuNENA plasticized propellant was compared by DSC test and cook-off numerical simulation, with the thermal safety property evaluated. The decomposition activation energy Ea and self-ignition temperature Tb of BuNENA plasticized propellant was lower than that of NG/BTTN plasticized propellant. Two kinds of propellant responded in the central area during slow cook-off simulation while in the near shell area during medium cook-off simulation. During fast cook-off simulation, depending on the different thickness of insulator, propellant responded at the area near shell or the area near the caps. The response temperature of two propellants in cook-off simulation agreed with decomposition and self-ignition temperature by DSC, and the decomposition of plasticizer could trigger the response. In cook-off simulation, BuNENA plasticized propellant showed a lower response temperature with a smaller high temperature area before response, resulting a milder response and better thermal safety than NG/BTTN plasticized propellant.
Reclamation of Abrasive Slurry to Obtain SiC Ceramic Material
Authors: Yang Sheng Fu , Chen Chun Liang , Chien Kuang Li , Liang Chih Chao , Chuo Hsien Ho
Published: January 2022

In the period of silicon and silicon carbide wafer slicing process, the abrasive oil, silicon carbide (SiC), silicon and trace elements e.g., iron, zinc, copper, and nickel is generated as an oily mixture of insoluble matter. The SiC is the main component (>70%) in the abrasive slurry and the extraction of SiC from the slurry can eliminate the risk of illegal waste disposal and reduce the cost for the enterprises. In this study, a chemical separation process is applied to remove silicon particles and SiC can be extracted from the slurry mixtures. The X-ray diffraction analysis revealed that recycled material is moissanite with two crystalline polymorphs. The 3C and 6H X-ray powder pattern is observed and the cubic and hexagonal crystalline structure is revealed. The particle size distribution analysis showed that median value of purified SiC powder material is 9.8 μm.
Fracture Behavior of the Hot Rolled Strip’s Surface Scale Layer from Different Impacts Angles
Authors: Wang Shang , Hao Rui Can , Liu Hua Gang , Wang Xiao Chen , Yang Quan
Published: January 2022

In order to improve the energy efficiency of shot blasting impact descaling, a three-dimensional finite element impact descaling model was established. Based on the finite element model, the cracking behavior of the scale layer on hot rolled strip from different impacts angles was simulated. The results of finite element calculation and theoretical analysis show that: (1)Under the premise of constant velocity, the descaling area increases with the increase of impact angle, but the increasing rate tends to be moderate. (2)The depth of the impact tunnel and the residual compressive stress surface (-200 MPa) increase as the impact angle goes bigger. The ideal range of impact angle for shot blasting descaling should be 60°-75°.
Research on the Cutting of Rectangular Blanks to Solve the Two-Dimensional Problem
Authors: Ji Jun , Cui Jian , Shi Meng Di
Published: January 2022

This paper introduces the research background of the two-dimensional packing problem, classifies the rectangular two-dimensional packing problem, then analyses the pattern scheme of the classic test questions, and finally, studies the three factors that affect the utilization rate of the plate.
Influence of Nano Filler (ZrO2) on Optical and Thermal Studies of Potassium Doped Polyethylene Oxide Solid Polymer Electrolytes
Authors: Sripada Suresh , Reddy M. Chandrashekhar , Sreekanth T. , Siripuram Rajesh , Venkateshwarlu K.
Published: January 2022

Solid polymer electrolyte films made with potassium doped Polyethylene oxide using ZrO2 as nanofiller (70PEO-30KBF4-x ZrO2 where x = 1, 2.5, 5, 7.5, & 10 wt% ­­) were prepared by solution casting technique. Optical and thermal properties of polymer electrolyte films were studied by using Optical absorption and DSC techniques. From Optical absorption spectra, it is observed that fundamental absorption edge is shifted towards the higher wavelength side (range 259- 297 nm) with increase of nano filler (ZrO­2) concentration (1-10 wt %). Optical band gap for all electronic transitions (p=1/2, 2, 2/3 and 1/3) are found to be increased as incorporation of nano filler (ZrO2) which confirms the structural rearrangements takes place in polymer electrolyte films. Optical band gap for indirect allowed transitions (p=1/2) are found to be in the range of 1.93-3.34eV. Decrease in Urbach energy (4.8eV- 1.4eV) is associated with decrease in defect formation in host polymeric matrix (PEO-KBF4) as a result of embedded nano filler (ZrO2). DSC spectra analysis of polymer electrolytes has showed melting temperatures in the range 63.63-73.71°C and highest crystallinity is found to be 85 % (10 wt % ZrO­2). Enthalpy values are elevated with increase in nanofiller composition (ZrO2) in the present polymer electrolyte films.Keywords: PEO based polymer electrolytes, Solid polymer electrolytes, Optical and Thermal studies.
Structural and Transport Properties of La0.85Te0.15MnO3 Manganite and its Composite with Al2O3
Authors: Dadhania D.A. , Jadav G.D. , Chavda S.K. , Bhalodia J.A.
Published: January 2022

The manganite systems investigated during the present work are pure La0.85Te0.15MnO3 (LTMO) and its composite with 12% concentration of Al2O3 nano powder (LTMO + Al2O3). The materials were prepared by the modified auto combustion technique. The samples were characterized by X-ray diffraction. The powder X-ray diffraction pattern of pure LTMO at room temperature shows that sample is in single phase with no detectable secondary phases and the sample have a rhombohedral structure in hexagonal with the space group R3c. The XRD pattern of LTMO + 12% Al2O3 indicates the clear presence of Al2O3 nano phase in the composite. In the present study, the FTIR Spectroscopy of both samples was carried out. It is clear from the Vibrational assignment for the value of corresponding peak position of FTIR spectra that no extra unwanted impurity is present in samples. A quantitative analysis of the energy dispersive spectroscopy (EDS) data indicates that the observed concentration of elements are very close to the calculated values from its chemical formula. R-T measurements reveals that the addition of secondary phase in manganite strongly influenced on electronic and magnetoresistance behaviour. We summarise some of the salient features of the results.
Incorporation of Magnetite in Toughened PLA Nanocomposite: Tensile and Thermal Stability
Authors: Chen Ruey Shan , Ahmad Sahrim
Published: January 2022

In this study, liquid natural rubber (LNR) toughened polylactic acid (PLA) incorporated with magnetite (Fe3O4) nanocomposites were fabricated via melt-compounding in an internal mixer and followed by hot/cold pressing. The effects of ultrasonic treatment time (1-3 hours) and Fe3O4 (0.5-4.0 wt%) nanoparticles loading on tensile, morphology and thermal stability were investigated. Based on tensile testing results, the ultrasonication time of 1 hour was served as the most suitable treatment period to achieve the optimum distribution of Fe3O4 within PLA/LNR matrix. Among the investigated nanoparticles loading, 1 wt% Fe3O4 nanocomposite presented the highest tensile strength of 23.7 MPa, Young’s modulus of 1293.5 MPa and strain at break of 2.8%. SEM micrographs showed that the over-treated nanocomposites with 2-3 hours and over-high nanoparticles loading had resulted in the formation of clusters in the matrix. With increasing Fe3O4 loading, the decomposition of PLA/LNR nanocomposites was initiated earlier.
Effect of Halloysite Nanotubes on Physico-Mechanical Properties of Silk/Basalt Fabric Reinforced Epoxy Composites
Authors: Darshan S.M. , Suresha Bheemappa
Published: January 2022

Natural fiber reinforced polymer composites have become more attractive due to their high specific strength, light weight and environmental concern. However, some limitations such as low modulus and poor moisture resistance were reported. This paper presents the role of halloysite nanotubes (HNTs) on physico-mechanical properties of bidirectional silk and basalt fiber reinforced epoxy (SF-BF/Ep) hybrid composites. Vacuum bagging and ultra-sonication method were used for the fabrication of hybrid composite slabs. The effect of HNT loadings (1.5, 3 and 4.5 wt. %) on physico-mechanical characteristics like density, hardness, flexural and impact properties of SF-BF/Ep composites were determined according to ASTM standards. Experimental results revealed that the incorporation of HNTs improves the mechanical properties. The impact strength of SF-BF/Ep is predominant at 3 wt. % HNT loading where the impact strength surges to 568.67 J/m, which may render HNT filled SF-BF/Ep desirable for various toughness-critical structural applications. The test results demonstrated that SF-BF/Ep-3HNT coded composites exhibited improved mechanical properties among the all composites.
Electronic Properties of Aldehyde Complexes Using DFT for Electrooptical Activity
Authors: Prasanti Marla , Jha Anjali , Kumar Ch. Ravi Shankar
Published: January 2022

Characterization of materials infer for physical and chemical properties that depend on its molecular structure. Structure of molecule has its dependence on respective electrons of molecule under consideration occupying their positions that correspond to changes in density of electrons. Many theories of its kind were developed to study density of electrons with roots from wavefunction method and electron density method. Wavefunction method has its dependence with linear combination of atomic orbitals, Born approximation, variational principle ,potential energy surfaces for development of Huckel theory, Hartree fock self-consistent theory. Electron density method includes Ab-intio method and density functional theory is possible with Kohenberbg-Kohn existence theorem and Kohn Sham formalism. Density functional studies has diverted attention of researches for properties dependent on structure with use of quantum mechanical descriptors that influence chemical reactivity of molecule forming complexes with properties responsible for electrooptical activity. In the present work complexes with p-anisaldehyde were studied with set of anilines using Gaussian 16 package with B3LYP method. Studies in present work were analyzed from computed infrared spectra responsible for formation of complexes with shifts in wavenumbers; quantum mechanical descriptors for electronic properties. A feature of study is that complexes with p-nitroaniline have greater tendency influence on electronic properties responsible for electrooptical activity due to electrophilic nature.
Generalized Version of ISI Invariant for some Molecular Structures
Authors: Pattabiraman K. , Kameswari M. , Seenivasan M.
Published: January 2022

Degree related topological invariants are the bygone and most victorioustype of graph invariants so far. In this article, we are interested in finding the generalized inverse indeg invariant of the nanostar dendrimers D[r],fullerene dendrimerNS4[r], and polymer dendrimerNS5[r]. Keywords: nanotubes; inverse indeg invariant; nanostar dendrimers; fullerene dendrimer; polymer dendrimer
Axial Compression Behaviour Analysis of Insulated Concrete Form (ICF) Wall Panel with Fibre Cement Board
Authors: Shelton Joel Joseph , Izazs Mohammad , Daniel C. , Solomon A. Arun
Published: January 2022

Nowadays, one of the fastest growing technique is an Insulated Concrete Form (ICF). It has advantages like cost-effective, less maintenance, soundproof, energy-efficient, waterproof and disaster-resistant. ICF wall panels are made by interlocking Fibre Cement Board (FCB) sheet which poured in placed concrete. In this study, the behaviour of the ICF wall panel under axial compression is examined with experimental and analytical methods. ICF wall panels cast with various thickness and dense FCB are tested under axial compression. ICF panels with 1.2gm3/cm dense FCB with changing width of 6mm and 10mm were casted for experimental analysis. The experiments were carried out in an universal testing machine with the capacity of 600 kN. The maximum peak load of 540 kN is observed in FCB of 10mm thick and the maximum displacement of 13mm is observed in FCB80 at the peak load. An analytical investigation is carried with Euler’s crippling load equation and an average variation of 12% is observed between analytical and experimental results. It is concluded that the ICF system of construction provides desirable plastic behaviour against axial compressive loading. Hence ICF is recommended for construction to get the maximum benefits of the wall while it reaches ultimate strain.
Microstructure Evaluation on Micro and Nano Slag Particles Reinforced AA7075 Composites
Authors: lakshmi Ippey Gopi , Kanth Yajjala Ravi , Murthy Inampudi Narasimha , Rao Jinugu Babu
Published: January 2022

The research work was focused on utilization of solid industrial waste. In order to investigate the properties of Fe-Cr slag particulates strengthened AA7075 composites. In this paper addition of ferrochrome slag particles as reinforcement in AA 7075 alloy processed through stir casting technique. By varying size of ferrochrome slag particles were added to evaluate the size effects in the given alloy matrix. Prepared composites were subjected to heat treatment and evaluated for microstructure analysis. The results show that there is a uniform distribution of particles in the matrix and that there is a strong bond between the matrix and the reinforcement. Grain refinement in the alloy matrix is observed by inducing slag particles. Further nanocomposites show lower grain size values.
Mechanical Extraction of Neem Seed Kernel (Azadirachta indica A. Juss.) Harvesting in Ninh Thuan, Viet Nam by Using Hydraulic Pressing: Effect of Processing Parameters
Authors: Do Dinh Nhat , Pham Hoang Danh , Le Xuan Tien , Le Minh Tuan , Nguyen Ngoc Phuong , Bui Quang Minh , Luu Xuan Cuong
Published: January 2022

Neem (Azadirachta indica A. Juss.) oil has been widely used in pharmaceuticals and cosmetics. The oil was extracted by the hydraulic press at the pilot scale. The effect of various critical factors such as the morphology of material, moisture of the neem seed, applied pressure, a number of presses turn, pressing time on the oil yield was considered. It was found that the oil yield increased with increasing applied pressure and pressing time. The moisture content of the neem seed kernel has a great influence on the oil yield, the higher the moisture content, the harder it is to recover the oil. The highest oil yield of 378mL/kg dry seed kernel was obtained at 190 MPa, 4% moisture content for 10 minutes of pressing per turn, and 3 turns of pressing. The main ingredients in neem kernel oil were oleic acid (45.9%), stearic acid (18%), palmitic acid (16.9%), and linoleic acid (15.65%). The results obtained can be used in the production of Neem oil at an industrial scale.
Hydrolysis of S. platensis Using Sulfuric Acid for Ethanol Production
Authors: Megawati  , Damayanti Astrilia , Putri Radenrara Dewi Artanti , Bahlawan Zuhriyan Ash Shiddieqy , Mastuti Astika Arum Dwi , Tamimi Riska Annisa
Published: January 2022

S. platensis is a microalga that contains carbohydrate composition of 30.21% which makes it potential to be used as raw material for ethanol production. Hydrolysis of S. platensis is the first step for converting its carbohydrates into monosaccharides. The second step is fermentation of monosaccharides into ethanol. This research aims to study the effect of temperature and microalgae concentration on the hydrolysis of S. platensis using sulfuric acid as catalyst. This research was conducted using 300 mL sulfuric acid of 2 mol/L, hydrolysis temperatures of 70, 80 and 90 °C, and microalgae concentrations of 20, 26.7, and 33.3 g/L. The effect of temperature is significant in the hydrolysis of S. platensis using sulfuric acid. At microalgae concentration of 20 g/L and hydrolysis time of 35 minutes, the higher the temperatures (70, 80, and 90 °C), the more the glucose yields would be (8.9, 13.5, and 22.9%). This temperature effect got stronger when the hydrolysis was running for 15 minutes. Every time the hydrolysis temperature increased by 10 °C, the glucose yield increased by 13.0% at microalgae concentration of 33.3 g/L. At temperature of 90 °C and time of 35 minutes, the higher the microalgae concentrations (20, 26.7, and 33.3 g/L), the higher the glucose yields would be (25.5, 27.7, and 28.2%). The highest glucose concentration obtained was 2.82 g/L at microalgae concentration of 33.3 g/L, temperature of 90 °C, and time of 35 minutes.
A Novel Method to Choose the Experimental Parameters in Large Amplitude Oscillatory Shear Rheology
Authors: Kodavaty Jagadeeshwar , Pannala R.K. Pavan Kumar , Wasson Sakshi , Mittal Mihir , Irshad Atif
Published: January 2022

Large Amplitude Oscillatory Shear (LAOS) rheology is a technique to analyze materials that are viscoelastic in nature. The raw values of stress and strain that were taken out from rheometer during the large amplitude oscillatory shear test are used in the constitutive models. The model parameters from the constitutive model are then analyzed on the materials being tested. Various test protocols and geometries will be used to analyze the materials of interest during LAOS rheological examination. The selection of test protocols and usage of geometry are less studied in testing various kinds of materials using LAOS. Cone and plate and parallel plate geometries are generally used for LAOS. The test protocols would be varying amplitude and varying frequencies. In the present work, quantification of relative performance of test protocols and geometry that have been used during the analysis of cross-linked poly vinyl alcohol hyaluronic acid (PVAHA) gels as material systems are studied using data envelopment analysis (DEA). The methodological approach using output oriented constant return to scale (CRS) and output oriented variable return to scale (VRS) are tested with the decision making units (DMU) as the geometry and test protocols used. These results are then combined with the Shannon's entropy to rank the efficient DMUs. Using Shannon's entropy combined with CRS and VRS, it is suggested that the use of parallel plate geometry with the test protocol of 0.5 rad/s and 50 frequency is best suitable for the cross-linked hyaluronic acid and poly vinyl alcohol gels examined.
Characterization and Comparison of Areca Sheath Ash (ASA) and Rice Husk Ash (RHA) for Silica Potential
Authors: Kulkarni Prasanna P. , Siddeswarappa B. , Channalli Mallikarjun
Published: January 2022

Utilization of agricultural by products as a reinforcement which offers a effective consequences on composite materials in the present days. Also a number of the agro waste substances as an ash are secondary filler material for Metal matrix composite materials. In this paper observe changed into achieved on characterization of agriculture waste ashes like Rice husk ash (RHA) and ASA (Areca sheath ash), burned at Controlled temperatures at 650°C in a metallurgical furnace at 3 exceptional durations of instances like 1hr, 2hr, and 3hr. Also each ashes were chemically and physically characterized, consequently decide the proportion of composition. The ensuing ashes have been analyzed the use of chemical evaluation via XRF and volumetric, gravimetric and instrumental test, SEM and EDS to determine their chemical composition which may be similarly used as reinforcement with metal matrix composites. Results acquired that impact of burning temperature and time on Chemical composition, Physical property, Loss of ignition (LOI) and Density. The ashes have been discovered to include excessive percent of silica content of 90% to 92% in Rice husk ash and 74% to 78% in Areca palm leaf sheath ash, after which accompanied through alumina content of 0.89% to 0.98% in each substances at 650oc temperatures respectively, additionally density of 0.98gm/cc for RHA and 1.12gm/cc Areca palm leaf sheath ash. Loss on ignition (LOI) of 4.5% to5.5% acquired on the equal temperature. These consequences suggests that rice husk ash and Areca sheath ash include excessive percent silica and a few alumina and may be utilized in chemical formulations requiring silica which include in metal matrix composites.
Influence of canopy architecture on the light interception, photosynthetic and biomass productivity in irrigated elite Sri Lankan rice varieties
Authors: Mubarak A. N. M. , Mufeeth Musthapha , Roshana M. R. , Kumara A. D. N. T.
Published: January 2022

Purpose: Canopy light interception and extinction play a crucial role in determining crop yield. Developing new rice varieties with improved canopy architecture along with modified intrinsic photosynthetic mechanisms will ensure the global food security. However, a comprehensive understanding of local rice varieties addressing on such avenues have not been reported. Hence, our pioneering experiments were carried out to elucidate such underlying properties among locally developed two elite rice varieties viz; At-362 and Bg 94-1 grown in the Ampara district of Sri Lanka. Research Method: The field experiment was carried out at the Agro Tech Park, Malwatta (7°20'N and 81°44'E altitude 16.0 m above sea level) between October 2019 to January 2020 implemented with Randomized Complete Block Design with four replicates. The Photosynthetically Active Radiation (PAR) distribution on the above and below canopy level was measured during the pre and post-anthesis stages. Then leaf stomatal conductance, chlorophyll fluorescence parameters and the chlorophyll content were also measured. At harvest, the final biomass produced were compared. Findings: The result revealed that variety At-362 had a higher Leaf Area Index (LAI) of 2.64 at pre anthesis and tend to decline at the latter part of their growth cycle. The striking feature was the extinction coefficient (k) seems to be much lower (0.47) in the At-362 variety than the Bg 94-1 (0.60) depicting that the former has produced vertical leaves (erect-leaf type) while the latter tends to produce horizontal leaf plans in the canopy. Hence, light attenuation was high and eventually, the bottom canopy layer received much lower PAR. Furthermore, LAI had a strong negative correlation with understory PAR indicating that the canopy architecture with an improved light interception will lead to permit more light penetration and utilization through the improved quantum yield efficiencies than the horizontal canopies. Hence significantly (p<0.05) improved above-ground biomass and panicle weight were observed in At-362. Originality/value: This experiment depicts that rice yield could be further improved through introgression of canopy architectural features along with improved photosynthetic traits.
Effects of dietary supplementation of ginger, garlic and onion on semen profile, haematological and serum antioxidant status of rabbit bucks raised in the dry season of the humid tropic
Authors: Ajao B. H. , Ola S. I.
Published: January 2022

Purpose: The study evaluated the semen, haematological and antioxidant status of rabbit bucks fed ginger, garlic and onion supplemented diets under a severely heat stressed condition. This is to evaluate the effect of heat stress and spice supplementation on seminal parameters, haematology and antioxidant capacity of rabbit buck raised in the tropics. Research method: Fifty - five bucks were allotted to 11 treatments comprising of control diet, three each of ginger, garlic and onion at 5g, 10g and 15g/kg feed plus positive control diet. Seminal, haematological and antioxidant traits of the bucks and their pen's Temperature – Humidity index (THI) were observed for 8 weeks. Findings: THI (29.30 - 31.10°C) recorded during the study indicated the prevalence of severe to very severe heat stress. Heat stress impacted negatively more on sperm morphology than on other seminal parameters. Sperm cell motility, viability and abnormality were similar within supplemented groups and the controls. Semen volume and concentration were highest in animals fed garlic at 10 and 15g/kg feed respectively. Spice supplementation had no significant effect (p>0.05) on the haematology and total antioxidant capacity (TAC) of the experimental animals. Originality/value: The study concluded that spice supplementation mitigated heat stress effect on sperm cell morphology and was not deleterious on haematology and TAC of the bucks.
COVID-19 IN CHILDREN AND ADOLESCENT: CHARACTERISTICS AND SPECIFICITIES IN IMMUNOCOMPETENT AND ONCOHEMATOLOGICAL PATIENTS
Authors: Mercolini Federico , Cesaro Simone
Published: January 2022

SARS-CoV-2 pandemic affected less children and adolescents, morbidity and mortality figures being inferior to that reported for adults. In this review we focused on the clinical course, risk factors for severe COVID-19, mortality, treatment options and prevention measures in the pediatric and adolescent setting with special attention to the pediatric oncohematological patients. In this subgroups of patients, SARS-CoV-2 infection was often asyntomatic but 47 to 68% of patients require hospitalization and 9-10% of those hospitalized needed intensive care with a COVID-19 attributable mortality of about 4%. The multisystem inflammatory syndrome associated to Coronavirus 2019 was less frequent than that reported in the non-oncohematological pediatric population. Noteworthy, the course of COVID-19 was more severe in low-middle income countries. The key measures to prevent SARS-CoV-2 infection are the reduction of patients exposure to the SARS-CoV-2 and vaccination, now available fore care givers and parents and for patients and siblings > 12 years old. The treatment of COVID-19 in pediatric patients was mainly based on supportive care with dexamethasone and heparin prophylaxis for severely ill patients. Other measures, such as convalescent plasma, remdesivir and monoclonal antibodies have been used in limited case or within experimental protocols. Further studies are needed on the risk factors and outcome of SARS-CoV-2 infection in the pediatric immunocompromised patients.
NURSES’ PHYSICAL AND PSYCHOLOGICAL SYMPTOMS DURING THE FIRST COVID-19 LOCKDOWN IN ITALY
Authors: Botti Stefano , Cannici Chiara , Liptrott Sarah , De Cecco Valentina , Rostagno Elena , Gargiulo Gianpaolo , Orlando Laura , Alessandro Caime , Samarani Emanuela , Galgano Letizia , Cioce Marco , Mordini Nicola , Mandelli Nadia , Tombari Lucia , Errichiello Sara , Celon Nicola , Lupo Roberto , Rea Teresa , Serra Nicola
Published: January 2022

Background and objective: Northern Italy was one of the first European territories to deal with the Coronavirus Disease 2019 (COVID-19) outbreak. Drastic emergency restrictions were introduced across the country to contain the spread and limit pressure on healthcare facilities. Nurses were at high risk of developing physical, mental and working issues due to professional exposure. The aim of this cross-sectional study was to investigate these issues among nurses working in Italian hematopoietic stem cell transplant (HSCT) programmes during the COVID-19 pandemic.

Methods: Data were collected online immediately after the first "lockdown" period in order to investigate the prevalence of physical issues, sleep disorders and burnout symptoms and explore correlations with COVID-19 territorial incidence in Northern Italian regions versus Central and Southern Italian regions.

Results: Three hundred and eight nurses working in 61 Italian HSCT Units responded to the survey. Depression, cough and fever were more frequently reported by nurses working in geographical areas less affected by the pandemic (p=0.0013, p<0.0001 and p=0.0005 respectively) as well as worst sleep quality (p=0.008). Moderate levels of emotional exhaustion (mean±SD - 17.4±13.0), depersonalization (5.3±6.1) and personal accomplishment (33.2±10.7) were reported without significant differences between territories.

Conclusions: different COVID-19 incidence among territories did not influenced nurses’ burden of symptoms in HSCT setting. However, burnout and insomnia levels should be considered by health care facilities in order to improve preventive strategies.
Severe immune thrombocytopenia (ITP) following SARS-CoV-2 mRNA vaccine in a girl on immunosuppressive treatment and in prolonged stable phase of ITP.
Authors: BIANCHI SIMONA , ANGI ALESSIA , PASSUCCI MAURO , PALUMBO GIOVANNA , BALDACCI ERMINIA , TESTI ANNA MARIA
Published: January 2022

Rare cases of immune thrombocytopenia (ITP) occurring after SARS-CoV-2 mRNA vaccines have recently reached public attention. It has been reported in patients with previous ITP or other autoimmune diseases and in individuals with an apparent negative past medical history.  The management and the outcome of these cases are still not well investigated and reported in the medical literature. A 23-year-old female with a past medical history of ITP, in stable complete remission for 3 years and on mycophenolate treatment received SARS-CoV-2 mRNA vaccine. She presented severe ITP recurrence with hemorrhagic symptoms after the second vaccine dose. A combined treatment with high-dose immunoglobulin and prednisone was successfully administered with a full recovery of platelet count. The patient remains in ITP remission and on mycophenolate therapy, five months later. At our Center, none of the other 76 adult “fragile patients” with ITP on immunosuppressive treatment who had received the SARS-CoV-2 mRNA vaccine, developed such a severe thrombocytopenic recurrence. Follow-up of large cohorts of patients receiving mRNA vaccine will answer the question as to whether it increases the risk of autoimmune conditions. So far, the benefits of the vaccination largely outweigh the risk of infection in these patients.
Morbidity audit of 704 traumatic brain injury cases in a dedicated South Indian trauma center
Authors: Singh Anil , Jena Ranjan , Pal Ranabir , Munivenkatappa Ashok , Reddy V , Hegde Kishore , Kumar S , Agrawal Amit
Published: January 2022

Background: In the era of evidence-based health care, protocol of intervention in traumatic brain injury (TBI) cases help decide more easily and safely about patients and prevent unnecessary transfer of patients to other centers. Objectives: The objective of this study is to provide protocol-based intervention and evaluate the epidemiological, clinical characteristics of TBI cases. Methods: This prospective study was conducted on 704 patients who were suspected of TBI at the Department of Neurosurgery, Narayana Medical College and Hospital, followed by protocol-based intervention assessed and reassessed repeatedly. Results: Overall, TBI involved 569 (80.82%) adults in the productive age groups (21–60 years); among males 81.47%. Among males, highest (23.15%) cases were in the age group of 31–40 years while in females, majority (27.04%) was among 41–50 years. Road traffic accidents were the most common (54.12%) mechanism of injury followed by fall (21.31%) and two-wheelers (15.20%). More than half sustained mild TBI (51.42%) while 26.28% moderate TBI and 22.30% severe TBI; among males, severe TBI victims 102 (18.82%) were in the productive age group. Loss of consciousness was almost a universal and significant observation (95.45%); vomiting was next common finding (76.42%). Bleeding from the ear-nose-throat (ENT) region was more in males (33.58%) than females (20.75%). Glasgow coma scale was significantly related with loss of consciousness (91.08%), vomiting (63.06%), and ENT bleeding (44.59%) in severe, moderate, and mild injuries. Conclusion: A rational clinical acumen with judicious use of diagnostic protocol leads to better management of TBI without unnecessary imaging and thus reduce total health-care costs.
Magnetic resonance imaging and neuropsychological correlates of subcortical vascular dementia
Authors: Paul Mohd , War Firdous , Sharma Vibha , Kushwaha Suman
Published: January 2022

Common understanding of dementia is mostly based on the Alzheimer's disease model. However, in subcortical vascular dementia (SVaD), several other cognitive and behavioral dysfunctions predominate over what is commonly noticed in Alzheimer's disease. There are inconsistencies in literature regarding the profile of cognitive impairments in vascular dementia. Objective: In the current study, different cognitive functions pertaining to different lobes of the brain along with neuropsychiatric symptoms we explored in a holistic manner. Materials and Methods: A sample of 12 patients diagnosed with SVaD without any comorbidity were recruited for the study. All the patients underwent magnetic resonance imaging (MRI) scanning and different standardized neuropsychological tests were administered. Results: Patients reported various neuropsychiatric symptoms with varied severity, mostly falling in moderate range, reflecting organic personality change. Most of the cognitive functions pertaining to different lobes of the brain were impaired with parietal lobe being intact mostly. Comparison of MRI findings and neuropsychological findings revealed that there is involvement of cortical functions with the impairment in subcortical structure. Conclusion: These findings emphasis need to look beyond clinical diagnosis and MRI findings for better rehabilitation of the patients by including cognitive dysfunction as well as emotional disturbances prominent in SVaD which might me quite distressing for caretakers.
Intraoperative neurophysiological monitoring in surgical treatment of spinal dural arteriovenous fistulas: Technique and results
Authors: Ghadirpour Reza , Nasi Davide , Iaccarino Corrado , Romano Antonio , Motti Luisa , Farneti Marco , Pascarella Rosario , Servadei Franco
Published: January 2022

Objective and Background: Data on intraoperative neurophysiological monitoring (IOM) during surgery of spinal dural arteriovenous fistulas (SDAVFs) are lacking. The purpose of this study was to evaluate the role of IOM during microsurgery for SDAVFs. Materials and Methods: From March 2007 to March 2013, 12 patients had microsurgery with IOM for SDAVFs. The IOM included somatosensory-evoked potentials, motor-evoked potentials (MEPs), and – in selected cases – D-Waves. All patients were evaluated at admission and at follow-up (6, 12, and 24 months) with Aminoff–Logue Disability Scale for Gait-Aminoff–Logue Disability Scale (G-ALS) and Micturition-Aminoff–Logue Disability Scale (M-ALS). Statistical Analysis Used: Logistic regression was used for detecting the clinical risk factors influencing neurological functions after the treatment. Results: During surgery, we registered the absence of significant modifications of evoked potentials in nine cases (75%), while improvement of MEPs occurred in three cases (25%). No false-negative case was registered, and IOM predicted the absence of new postoperative neurological deficit in all patients. At 24-month follow-up, nine patients improved their overall neurological status, while three patients remained stable. At univariate analysis, Aminoff–Logue Disability Scales for Gait and Micturition (G + M-ALS) score at 24-month follow-up was directly associated with the duration of symptom before the surgery (P = 0.024), preoperative G-ALS (P = 0.02), M-ALS (P = 0.022), and G + M-ALS scores (P = 0.045), and improvement of IOM after occlusion of the fistula (P = 0.025). Conclusions: In our series, no significant worsening of evoked potentials occurred and subsequently the surgical strategy was not changed by IOM. However, no false-negative case was registered, and IOM predicted the absence of new postoperative neurological deficit in all patients. Patients with improvement of IOM parameters after occlusion of the fistula had greater chances of postsurgical improvement at the univariate analysis.
Pyothorax-associated angiosarcoma metastasized to the brain with multiple and progressively expanding hematomas: Case report and literature review
Authors: Hagiwara Shinya , Miyazaki Takeshi , Ishikawa Noriyoshi , Nakagawa Fumio , Maruyama Riruke , Akiyama Yasuhiko
Published: January 2022

The brain metastasis of angiosarcoma is very rare, and little is known about its clinical features or therapeutic strategy. A 74-year-old male was hospitalized for disturbance of consciousness. Radiological examination revealed multiple cerebral hematomas. Gadolinium contrast-enhanced magnetic resonance imaging showed no significant enhancement at any of the lesions. To detect a suspected metastatic brain tumor or abscess, a full-body scan was performed but revealed only a poorly enhanced mass in the removal cavity caused by thoracoplasty in the left upper chest. After admission, a cascade of expansion of those hematomas occurred in the right frontal, left parietal, and right temporal lobes, and each lesion thus had to be sequentially removed by craniotomies. The pathological diagnosis of the right frontal lesion was an abscess with hematoma. However, a malignant vascular tumor was highly suspected because of many CD31(+)/Ki-67(+) cells in the left parietal lesion. A mass in the scar caused by thoracoplasty was suspected to be the primary lesion, and brain metastasis of angiosarcoma was finally diagnosed. Whole-brain irradiation and systemic paclitaxel administration were performed, and a complete response for the brain lesions was obtained for 22 months; the patient then died of an intratracheal hemorrhage. This case represents the first report of multiple brain metastases from pyothorax-associated angiosarcoma accompanied by sequentially and gradually expanding hematomas, as well as the first case with the control of metastatic brain lesions for over 1 year after the onset of neurological symptoms. Control of the lesions could be achieved by their total removal with complete hemostasis, as well as additional radio- and chemotherapy.
What do you expect from patients with severe head trauma?
Authors: Salehpour Firooz , Bazzazi Amir , Aghazadeh Javad , Hasanloei Amin , Pasban Khatere , Mirzaei Farhad , Naseri Alavi Seyed
Published: January 2022

Background: Head trauma is one of the most common mortality and morbidity causes in adolescent. Numerous studies have been conducted on changes in laboratory results and mortality and morbidity prognostic factors; however, the obtained results have been varied and controversial. The aim of this study is to evaluate changes in laboratory findings and arterial blood gas (ABG) analyses test at admission and investigation of the relation between these changes with outcomes in patients with traumatic brain injury. Materials and Methods: In this study, laboratory and metabolic variables were compared in patients with severe brain trauma and normal subjects. Laboratory and metabolic variables and ABG were measured on admission in patients with severe brain trauma and then compared with normal values. At last, the correlation between these variables with the prognosis in the patients was studied. Results: Of 93 studied patients, 82 were male and 11 were female with the mean age of 30.54 years. Among the studied variables, prothrombin time (PT), partial thromboplastin time, international normalized ratio (INR), creatinine (Cr), blood sugar, sodium (Na+), potassium, white blood cell, and blood urea nitrogen increased while hemoglobin and platelet decreased significantly. Regarding the ABG results, the difference in PaCO2, HCO3, and SO2at values was significant; whereas there were no statistical significant difference between the discharged and expired patients. In contrast, PT, INR, Cr, and Na had significant difference comparing the discharged and expired patients. Conclusion: Laboratory variables do change in patients with severe brain trauma; these changes are influential on patient prognosis, especially in case of PT, INR, Cr, and Na.
Contemporary updates on clinical trials of antiangiogenic agents in the treatment of glioblastoma multiforme
Authors: Kochar Arshneel , Madhavan Maya , Manjila Sunil , Scoco Aleka , Belle Vaijayantee , Geertman Robert
Published: January 2022

Glioblastoma multiforme (GBM) has the highest rate of vascular proliferation among solid tumors. Angiogenesis is the central feature of rapid tumor growth in GBM and therefore remains an appealing therapeutic target in the treatment of these highly malignant tumors. Antiangiogenic therapy is emerging as an important adjuvant treatment. Multiple antiangiogenic agents targeting various sites in vascular endothelial growth factor (VEGF) and integrin pathways have been tested in clinical trials of newly diagnosed and recurrent GBMs. These include bevacizumab, enzastaurin, aflibercept, cediranib, and cilengitide. In this review, we discuss the current status and challenges facing clinical application of antiangiogenic treatment including anti-VEGF therapy and integrin pathway agents' therapy in glioblastoma. Here, we highlight a strong biologic rationale for this strategy, also focusing on integrin pathways. PubMed-indexed clinical trials published in English on antiangiogenic treatment of glioblastomas in the past 5 years were reviewed. The results of the current clinical trials of these agents are presented.
Trans-Cranial embolisation of a complex transverse sigmoid sinus dural arteriovenous fistula by direct puncture of the superior sagittal sinus
Authors: Lammy Simon , Bhattacharya Joti , Dervin James , Jerome Edward , George St.
Published: January 2022

This technical note describes a direct puncture of the superior sagittal sinus (SSS) to treat a complex dural arteriovenous fistula (dAVF). A 40-year-old female was admitted having a history of increasing confusion. Computer tomography revealed enlargement of the right superior ophthalmic vein and magnetic resonance imaging demonstrated extensive bilateral hemispheric venous engorgement. Digital subtraction angiography (DSA) demonstrated a high flow dAVF involving the right transverse sinus. There was extensive cortical venous rerouting with venous sinus occlusion at the right transverse and sigmoid junction. Under general anesthesia, the sinus was exposed and catheterized. The angiography catheter was fed over the guide wire into the sinus. The remaining right sigmoid and transverse sinus were obliterated using a combination of microcoils and Onyx®. She made a good postoperative recovery, and a repeat DSA at 30 days postoperatively showed evidence of the meningohypophyseal trunk but complete occlusion of the fistula. A check DSA 2 years later confirmed no evidence of a residual fistula. Our case demonstrates the potential use of the SSS as a novel conduit to treat distant targets.
Iodinated contrast encephalopathy after coil embolization of unruptured aneurysms
Authors: Onishi Shumpei , Sakamoto Shigeyuki , Okazaki Takahito , Kurisu Kaoru
Published: January 2022

Iodinated contrast encephalopathy is known as one of the rare complications of cerebral angiography and neurovascular intervention. The mechanism and causes of contrast encephalopathy are not understood well. In this case, we experienced transient neurological deficit following coil embolization of unruptured aneurysms. A 67-year-old woman with two unruptured aneurysms of internal carotid artery underwent endovascular coil embolization. During the procedure, she presented transient hemiparesis and aphasia. After the treatment, she presented the symptom again, and computed tomography scan showed cortical edema and subarachnoid leakage of contrast agent. Magnetic resonance imaging excluded cerebral infarction. The neurological symptom resolved completely within 24 h after the treatment, and she was diagnosed as the contrast encephalopathy. In our case, we speculated that contrast encephalopathy has occurred subsequently to the transient cerebral ischemia. Iodinated contrast encephalopathy may have induced with neurovascular intervention following cerebral ischemia and increased use of contrast agent. We should consider iodinated contrast encephalopathy when a patient presents hemiparesis and aphasia such as that caused by acute stroke during neurovascular intervention.
A rare case report of giant cell tumor of the sphenoid bone in a patient who developed “erythema multiforme associated with phenytoin and cranial radiation therapy syndrome”
Authors: Biswas Rituparna , Halder Anirban
Published: January 2022

Giant cell tumors (GCTs) are rare, usually affecting the epiphyses in long bones of the extremities. GCTs may be locally aggressive with a high rate of local recurrence and exhibit the potential for distant metastasis. They seldom occur in the skull, where they preferentially affect the sphenoid and temporal bones. Several case reports with follow-up describe gross total resection of skull-base GCT to be curative. Radiation therapy, although controversial, is reserved for lesions that cannot be completely resected. Here, we describe the case of an 18-year-old female with GCT of sphenoid bone who underwent subtotal resection followed by adjuvant radiotherapy, although whose radiotherapy could not be completed because of her demise due to erythema multiforme associated with phenytoin and cranial radiation therapy syndrome.
Study of incidence and factors: Risk and preventive, of chronic subdural hematoma/hygroma in clipped patients of unruptured intracranial aneurysms – An institutional experience
Authors: Kawase Tsukasa , Bishnoi Ishu , Tanaka Riki , Dash Chinmaya , Kato Yoko , Yamada Yoshiru
Published: January 2022

Introduction: One of the underreported complications of clipping of unruptured aneurysm is chronic subdural hematoma/hygroma (CSDH). It can cause sudden deterioration and might need emergency evacuation. Recently, very few papers have studied its incidence and predisposing factors. We are reporting our institutional experience of it along with the study of its risk factors and possible pathogenesis. Methodology: Totally 91 postoperative patients of unruptured aneurysms were retrospectively analyzed. Totally 21 patients had CSDH who were operated. In rest seventy patients, there was no CSDH. Results: Male sex, old age, anticoagulant use, presence of pneumocephalus and dead space were significantly associated with occurrence of CSDH, whereas arachnoidoplasty significantly protected against it. There was no significant relation of CSDH with Gorei-san use. Conclusions: We recommend arachnoidoplasty should be carried out in all patients of clipping of unruptured aneurysm. Male patients or/and patients with dead space with pneumocephalus must be given extra attention like avoiding any dead space in postoperative period, doing arachnoidoplasty and regular follow up till 1st year.