scholarly journals “Green” Synthesis of Nanocarbons for Reduced Friction and Wear

Lubricants ◽  
2020 ◽  
Vol 8 (2) ◽  
pp. 13
Author(s):  
Maria Sarno ◽  
Adolfo Senatore ◽  
Davide Scarpa ◽  
Claudia Cirillo
Keyword(s):  
Friction And Wear ◽  
Physicochemical Characterization ◽  
Tween 80 ◽  
Tribological Performance ◽  
Wear Scar Diameter ◽  
Group Iii ◽  
Group I ◽  
Reduced Graphene ◽  
First Time ◽  
Remarkable Reduction

In the following study, green carbon nanotubes and green few-layer reduced graphene oxide (rGO) were synthesized through simple, sustainable, and scalable processes starting from recycled plastic and charcoal, respectively, and with the highest number of steps involving non-harmful substances. After an extensive physicochemical characterization, which evidenced that both nano-carbons exhibit structures comparable with that of materials produced through more traditional methods and from pure sources, the samples were dispersed in two types of conventional base oils, in particular group I and group III, in order to carry out, for the first time on these green nanomaterials, an accurate study on their tribological performance. Tribological tests evidenced a remarkable reduction of coefficient of friction and wear scar diameter, especially for the green rGO dispersed at 0.1 wt% in the group III oil along with SDBS-Tween 80 surfactants mixture: 18% and 15% at ambient temperature, 12% and 13% at 80 °C, respectively. Furthermore, the tribological performance of the synthesized samples in both oils remained high for 160 min of investigation. A comparison with the same material obtained with a traditional synthesis revealed the absence of fouling phenomena in the lubrication chambers in our case, confirming the higher tribological performances of the green rGO sample, probably, as a consequence of its less ordered nature.

scholarly journals Epidemiological aspects of nephrolithiasis and chronic diseases of the cardiovascular system combination

2020 ◽  
Vol 7 (1) ◽  
pp. 38-47
Author(s):  
R. V. Royuk ◽  
S. K. Yarovoy ◽  
N. A. Guseva ◽  
Sh. L. Voskanyan ◽  
V. V. Royuk ◽  
...  
Keyword(s):  
Heart Failure ◽  
Coronary Heart Disease ◽  
Congestive Heart Failure ◽  
Heart Disease ◽  
Cardiovascular Diseases ◽  
Arterial Hypertension ◽  
Kidney Stones ◽  
Group Iii ◽  
Group I ◽  
First Time

Purpose of the study. To analyze prevalence and characteristics of the cardiovascular diseases (CVD) in patients with urolithiasis, revealed for the first timeMaterials and methods. In a period between 2009 and 2018, was made a retrospective analysis of medical histories of 2311 patients with urolithiasis, which were treated in in the urology departments of the branch No. 1 of the MCHG named after N.N. Burdenko (n=1487) and GBUZ MO Krasnogorsk City Hospital No. 1 (n=824). In 67,6% of the cases (1562 patients) the diagnosis of urolithiasis was diagnosed for the first time on admission. Isolated urolithiasis was recorded in 676 cases (43,3%), in other 154 cases (9,8%) nephrolithiasis was combined with different variants of cardiovascular diseases (CVD) and diabetes. From 732 respondents with urolithiasis and associated cardiovascular diseases (CVD), were formed 3 groups, in the first group (I) were included patients (n=363) with hypertension and arterial hypertension: the second group (II; n=79) was formed from patients with isolated coronary heart disease. In the third group (III) were included 290 patients which had urolithiasis combined with hypertension, arterial hypertension and coronary heart disease. The stages of hypertension and degree of expression of arterial hypertension were given according to the recommendations of Russian science society of cardiology (2004). Stages of congestive heart failure were defined according to c NYHA (New York Heart Association) classification. Functional class of stable angina was defined according to Canadian Cardiovascular Society classification (1970,1976). The obtained data was analyzed using descriptive statistics methods.Results. Average age of patients was 65,4 +– 3,27; 78% of the patients were men. On an emergency basis were hospitalized 30,9% from group I, 27,6% from group 2, and 31,3% from group III. In group I more often were recorded hypertension I + arterial hypertension I (32,5%) and hypertension II + arterial hypertension II (40,2%). In group II effort angina was recorded in 30 cases (38%). Congestive heart failure occurred among 153 patients (20,9%); most often it occurred among patients from III – in 102 cases (35,2%). In the whole sample, congestive heart failure of I and II degrees prevailed – in 88 (12%) and 57 (7,9%) patients. Kidney stones were found in 59,4% of patients, in the ureters – in 30,9% of patients, in kidneys and in the ureters – in 9,9% of patients. Share of the patients with kidney stones in the shape of corals is 3,4% of the whole sample. Average sizes of kidney stones of the patients with congestive heart failure are 9,2–11,8 mm which is different from the sizes in whole sample – 6,9–9,5 mm.Conclusion. During the observation period, share of the patients with first time revealed urolithiasis, complicated with the cardiovascular diseases (CVD) increased in 1,9 times (16,7 versus 31,7%). Congestive heart failure, which was registered in 20,9% of patients, was charged with I and II degrees. The presence chronic cardiovascular diseases (CVD), especially complicated by congestive heart failure in patients with first time revealed nephrolithiasis, implies changes in the algorithms of metaphylactic of nephrolithiasis (regime of water loads, selection of diuretics and anticoagulants).

scholarly journals Early diagnosis and misdiagnosis of Glaucoma

2016 ◽  
Vol 12 (2) ◽  
Author(s):  
Ghulam Sabir
Keyword(s):  
Intraocular Pressure ◽  
Early Diagnosis ◽  
Early Stage ◽  
Visual Fields ◽  
Fundus Examination ◽  
Group Iii ◽  
Group I ◽  
Initial Stage ◽  
Diagnosis Method ◽  
First Time

Aim: To recognize and draw a line between glaucomatous and non glaucomatous patients at very early stage. Objects: Such silent dangerous ocular problem must be recognized and treated at very initial stage to avoid subsequent complications. Diagnosis: History and all the parameters including intraocular pressure, vision, visual fields and fundus examination were evaluated for diagnosis. Method of study: The study was done at General Hospital and Services Hospital Lahore from 1987 to early 1991. All the patients over the age of 40 year whether coming for first time or already on antiglaucoma treatment were evaluated thoroughly. Patients were examined by senior colleagues also. Results: Total 180 patients were included in study, 120 males 60 females. They were divided into four groups. Group I and II were diagnosed early and included 120 patients with no complications. Group-III and IV were misdiagnosed and included 60 patients. Discussion Until and unless, special care is taken to focus on the diagnosis, it is usually missed with many complications. It is only the casual behaviour of treating physician who considers the patient`s complaint lightly and examines them superficially. Conclusion: Although misdiagnosed cases are relatively less than truly misdiagnosed cases of glaucoma yet they form an important fraction of patients who may go blind within coming years. It is therefore necessary to diagnose such patients at very early stage. The surgeon should take special interest to diagnose such patients. One should not hesitate to consult senior colleagues in doubtful cases. Proper counseling for non cooperative patients is very necessary.

scholarly journals Insertional Mutagenesis of a Fungal Biocontrol Agent Led to Discovery of a Rare Cellobiose Lipid with Antifungal Activity

2003 ◽  
Vol 69 (5) ◽  
pp. 2595-2602 ◽  
Author(s):  
Yali Cheng ◽  
David J. McNally ◽  
Caroline Labbé ◽  
Normand Voyer ◽  
François Belzile ◽  
...  
Keyword(s):  
Insertional Mutagenesis ◽  
Biocontrol Agent ◽  
Solid Phase ◽  
Antagonistic Effect ◽  
Group Iv ◽  
Active Metabolites ◽  
Group Iii ◽  
Group I ◽  
Multiple Copies ◽  
First Time

ABSTRACT Insertional mutagenesis was applied for the first time to a fungal biocontrol agent, Pseudozyma flocculosa, in an attempt to obtain mutants with altered antagonistic properties. Transformants were obtained via DNA-mediated transformation. Molecular analyses of the transformants revealed that multiple copies of the plasmid were integrated in tandem at one to many chromosomal loci. The transformants were screened for their biocontrol properties using standard bioassays, and the 160 tested transformants were classified into four groups: group I mutants (22 transformants) showed a stronger antagonistic effect than the wild type (WT) while those of group II (107 transformants) had a comparable antagonistic effect; group III mutants (17 transformants) had a decreased antagonistic effect relative to WT and group IV mutants (14 transformants) had lost their biocontrol properties. Culture extracts of the mutants (group IV) and WT were analyzed and compared for the presence of active metabolites which were then separated by solid-phase extraction and purified using conventional methods. Nuclear magnetic resonance experiments and analytical studies on a metabolite specifically produced by the WT revealed the presence of 2-(2′,4′-diacetoxy-5′-carboxy-pentanoyl) octadecyl cellobioside (flocculosin), a novel glycolipid with strong antifungal properties; the production of this compound would account for the biocontrol activity of P. flocculosa.

scholarly journals Neuroprotective Outcome of Thymol against Global Cerebral Ischemia Reperfusion injury in Albino Rats

2021 ◽  
pp. 38-48
Author(s):  
M. Hima Saila ◽  
Manga Devi Ch ◽  
Santhrani Thakur
Keyword(s):  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Tween 80 ◽  
Global Cerebral Ischemia ◽  
Albino Rats ◽  
Group Iii ◽  
Ischemic Reperfusion ◽  
Group I ◽  
Cerebral Ischemia Reperfusion Injury ◽  
Per Oral

Aims: The purpose of the present study was targeted to explore the possible role of thymol against global cerebral ischemia-reperfusion injury in albino rats. Study Design:  Healthy Albino Wistar rats (200–250 gm) were divided randomly into 5 groups (n=6).  Group I and II were considered as normal control and sham control, received 2% tween 80 orally, group III was ischemic- reperfusion (disease control) and received 2% tween 80 orally and Group IV and V received thymol at doses of 50 mg/kg, per oral and 100 mg/kg, per oral. respectively. Place and Duration of Study: Department of Pharmacology, Sri Padmavathi School of pharmacy, Tiruchanur, Tirupati in between Sept 2019 to March 2020. Methodology: Group I and II were considered as normal control and sham control, received  2% tween 80 orally, group III was ischemic- reperfusion (disease control) and received 2% tween 80 orally and Group IV and V received thymol at doses of 50 mg/kg, per oral (p.o) and 100 mg/kg, per oral (p.o). respectively. After pretreatment with thymol for 2 weeks, rats were subjected to bilateral common carotid artery occlusion for 1 hour accompanied by 22 hours reperfusion (I/R). After 22 hrs of reperfusion, motor coordination, hanging wire test, despair swim tests were studied. Antioxidant levels of reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT) and pro-oxidant level of Malondialdehyde (MDA) were analyzed in brain tissue homogenate. Changes in cerebral infarct size and histopathology were studied. Results: Pretreated groups of thymol (50 and 100 mg/kg p.o) showed significant improvement in neurobehavioral changes and attenuated oxidative damage as indicated by reduced LPO, restored GSH, SOD and CAT levels and decreased infract size when compared to ischemic reperfusion group. Conclusion: This study suggests that thymol may have a beneficial role against global ischemia reperfusion induced damage caused by excessive free radicals and behavioral alterations in rats.

scholarly journals Incidence of tuberculosis of bones and joints in Sumy region

2021 ◽  
pp. 95-99
Author(s):  
I.D. Duzhyi ◽  
G.P. Oleshchenko ◽  
K.L. Serdiuk
Keyword(s):  
Negative Consequences ◽  
Tuberculous Spondylitis ◽  
Ability To Work ◽  
Group Iii ◽  
Osteoarticular Tuberculosis ◽  
Group I ◽  
Number Of Patients ◽  
Long Time ◽  
First Time ◽  
Significant Lesion

Bones and joints, among other extrapulmonary organs, are most often affected by tuberculosis. The clinical picture is often «hidden», the diagnosis of the disease is delayed for a long time with all the negative consequences. Objective — to study the trend in the incidence of tuberculosis of the bone and joint localization of the Sumy region residents in recent years and draw the attention of general practitioners to the urgent problem of today. Materials and methods. We analyzed the incidence of tuberculosis of bones and joints of the Sumy region residents during 2007—2019. During this period, 200 patients with osteoarticular tuberculosis registered in the region. Results and discussion. Over the past 13 years, the number of patients with tuberculosis of the bone and joint localization averaged 2.5 % of all newly detected processes. Tuberculosis of the spine (spondylitis) occurred in 119 (59.5 %) patients, specific inflammation of the hip joint in 49 (24.5 %), knee — in 11 (5.5 %), ankle — in 6 (3.0 %). Tuberculosis of other bones and joints was found in 15 (7.5 %) patients, 60 (50.4 %) patients with tuberculous spondylitis were recognized as disabled for the first time. Of these, the group I was found in 19 (31.7 %), II — in 25 (41.7 %), III — in 16 (26.6 %). Conclusions. In recent years, there has been an increase in the proportion of patients with CST among all newly diagnosed patients in the Sumy region. The spine is most often affected by tuberculosis of the bones and joints (59.5 %). At the same time, a significant lesion (3—4 vertebrae) was recorded in 23 (19.3 %) persons, five and more vertebrae — in 19 (16.0 %) patients. Patients with tuberculous spondylitis in 50.4 % of cases permanently lost their ability to work. Most patients of groups I and II of disability and a significant number of patients of group III require surgical intervention; without its implementation, there are irreversible changes in the vertebrae, which lead to increased medical, biological, and social disability.

scholarly journals Effectiveness and Safety of Additive Therapy and Monotherapy of Glaucoma with Prostamides

2019 ◽  
Vol 16 (3) ◽  
pp. 366-370
Author(s):  
I. R. Gazizova ◽  
S. R. Zainullina ◽  
E. B. Martynova
Keyword(s):  
Adverse Reactions ◽  
Initial Level ◽  
Open Angle Glaucoma ◽  
Newly Diagnosed ◽  
First Line ◽  
Main Method ◽  
Group Iii ◽  
Group I ◽  
Additive Component ◽  
First Time

Increased intraocular pressure (IOP) is the main risk factor for the development of primary open-angle glaucoma (POAG). Nowadays medicine that reduce IOP remain the main method of treating for POAG. The first-line drugs for POAG are prostaglandin analogues. In Russia, for the first time, it appeared not in the form of a fixed combination (Bimoptic). In this regard it is very important to evaluate the clinical efficacy and safety of Bimoptic as a monotherapy and additive component in the treatment of patients with POAG. Patients and methods. Patients were divided into 3 groups depending on the treatment. Group I comprised of 34 patients with newly diagnosed glaucoma on monotherapy with bimatoprost 0.03 %. Group II consisted of 30 patients who started taking bimatoprost 0.03 % as a replacement for latanoprost 0.005 % or travoprost 0.004 %. There were 32 patients in group III, who were prescribed bimatoprost 0.03 % as an adjuvant therapy for B-blockers (BB) 0.5 % or carbonic anhydrase inhibitors (ICA) 2 %. Results. According to the results of the clinical study, it was found that instillation of Bimoptik as a monotherapy for newly diagnosed POAG leads to a decrease in IOP level by an average of 32.1 % of the initial level. With the additive tactics of assigning Bimoptik to the BB and / or IKA, the level of IOP goes down by 10.6 % more. If prostaglandin is changed to Bimoptik, the level of IOP decreases by 12.6 % of the prostaglandin-associated values. Also according to acquired data, Bimoptik has a low percentage of adverse reactions, slight hyperemia and discomfort were observed in 5.2 % of cases in all groups. Conclution. Bimoptik effectively reduces the level of IOP in both monotherapy and additive tactics with the least adverse reactions.

Friction and Wear Behaviour of Borided Ti6Al4v Alloy Sliding Against Al2O3 and Si3N4 Balls in Water

2011 ◽  
Vol 312-315 ◽  
pp. 1004-1009 ◽  
Author(s):  
Erdem Atar ◽  
E.S. Kayali ◽  
Huseyin Cimenoglu
Keyword(s):  
Friction And Wear ◽  
Tribological Performance ◽  
Ti6al4v Alloy ◽  
Wear Behaviour ◽  
Wear Loss ◽  
Destructive Action ◽  
Wear Mode ◽  
Remarkable Reduction

This study focuses on tribological performance of as-received and borided Ti6Al4V alloys against ceramic counterfaces (Al2O3 and Si3N4 balls) in water. The wear mode of the alloy changed from ploughing to polishing by achieving a remarkable reduction in wear loss upon boriding. On the borided surface, the destructive action of the Si3N4 ball was very limited, when compared to that of the Al2O3 ball.

scholarly journals Influence of incubation temperature and embryonic motility on the growth of members of Caiman yacare (Daudin, 1802)

2024 ◽  
Vol 84 ◽  
Author(s):  
L. G. Gomes ◽  
M. B. Stocco ◽  
N. P. de Sousa ◽  
A. C. Martini ◽  
T. O. Morgado ◽  
...  
Keyword(s):  
Temperature Variation ◽  
Incubation Temperature ◽  
Skeletal Development ◽  
Group Iii ◽  
Phenotypic Changes ◽  
Group I ◽  
Prenatal Ontogeny ◽  
Incubation Temperatures ◽  
Embryonic Motility ◽  
First Time

Abstract This study aimed to evaluate whether skeletal development of the Pantanal Caiman (Caiman yacare) is similarly influenced by temperature variation and controlled increases in embryo motility. All eggs were incubated at 90% humidity and 29 °C for the first 45 days. Thereafter, the incubation temperature was either maintained at 29 °C and embryos were treated with 4-aminopyridine (4-AP) on days 46, 47, 48, and 49 (Group I, 29 °C 4-AP, n = 15); maintained at 29 °C (n = 14; Group II); or at 33 °C (n = 14, Group III). Embryonic movement was measured using an Egg Buddy® digital monitor on days 30, 35, 42, 49, 56, and 60, at which point embryos were euthanized and samples were collected for analysis. No differences were observed between groups with varying incubation temperatures. In contrast, embryonic motility was greater in embryos treated with 4-AP (P < 0.001) on day 49, and this was associated with higher proportions of snout-vent and hand lengths. This study demonstrates for the first time that pharmacologically induced increases in embryo motility result in phenotypic changes to the proportion of elements during prenatal ontogeny, thereby effectively altering the adaptation of the species to specific environments.

Nanobacteria: An Infectious Cause for Salivary Stone Formation and Recurrence

2010 ◽  
Vol 3 ◽  
pp. CMENT.S5147
Author(s):  
Amr A El Badry ◽  
Mahmoud A.M. Mokbel ◽  
Ismail El Mofty ◽  
Amira H Mohamed
Keyword(s):  
Salivary Gland ◽  
Growth And Development ◽  
Stone Formation ◽  
Group Iii ◽  
Group I ◽  
Significant Difference ◽  
Group Ii ◽  
First Time ◽  
Normal Controls ◽  
Salivary Gland Stones

Nanobacteria (NB) contribute to pathological calcification in the human and animal body. It has been isolated from salivary stones and suggested that it may act as a nucleus for the initiation of these stones. In the present study, we examined its role in the recurrent salivary gland stones using immunodetection with NB-specific monoclonal antibodies and scanning electron microscopy (SEM) hoping to provide a method for preventing the recurrence of these stones in the patient that has suffered from salivary stones. Our study comprised 30 patients with recurrent salivary gland stones (group I) and 30 patients with salivary gland stones for the first time (group II), in addition to 30 normal controls (group III). We could detect 100–500 nm nanoparticles in 24/30 (80%) cases in group I with significant difference <0.05 and <0.01 when compared with group II and group III in which they were detected in 19/30 (63.3%) and 6/30 (20%) respectively. Also there was a significant difference <0.05 between group II and group III. We proposed that salivary stone formation is a nanobacterial disease initiated by bacterial infection. This bacteria may play an important role in the recurrence of salivary stone. So the use of calcium chelator, ethylene diamine tetra acetic acid (EDTA), before or in combination with the suitable antibiotic that is given in an amount effective to inhibit or prevent the growth and development of nanobacteria may eradicate these stones and prevent their recurrence.

Ultrastructural Lesions Produced by Alcohol and Sucrose in the Heart and Liver of C57BL Mice

1970 ◽  
Vol 28 ◽  
pp. 208-209
Author(s):  
K.K. SEKHRI ◽  
C.S. ALEXANDER ◽  
H.T. NAGASAWA
Keyword(s):  
Osmium Tetroxide ◽  
Male Mice ◽  
Alcohol Group ◽  
Group Iii ◽  
Group I ◽  
C57bl Mice ◽  
Group Ii

C57BL male mice (Jackson Lab., Bar Harbor, Maine) weighing about 18 gms were randomly divided into three groups: group I was fed sweetened liquid alcohol diet (modified Schenkl) in which 36% of the calories were derived from alcohol; group II was maintained on a similar diet but alcohol was isocalorically substituted by sucrose; group III was fed regular mouse chow ad lib for five months. Liver and heart tissues were fixed in 2.5% cacodylate buffered glutaraldehyde, post-fixed in 2% osmium tetroxide and embedded in Epon-araldite.

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