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1.
Molecules ; 29(15)2024 Aug 01.
Article in English | MEDLINE | ID: mdl-39125060

ABSTRACT

We report a transformative epoxy system with a microalgae-derived bio-binder from hydrothermal liquefaction processing (HTL). The obtained bio-binder not only served as a curing agent for conventional epoxy resin (e.g., EPON 862), but also acted as a modifying agent to enhance the thermal and mechanical properties of the conventional epoxy resin. This game-changing epoxy/bio-binder system outperformed the conventional epoxy/hardener system in thermal stability and mechanical properties. Compared to the commercial EPON 862/EPIKURE W epoxy product, our epoxy/bio-binder system (35 wt.% bio-binder addition with respect to the epoxy) increased the temperature of 60% weight loss from 394 °C to 428 °C and the temperature of maximum decomposition rate from 382 °C to 413 °C, while the tensile, flexural, and impact performance of the cured epoxy improved in all cases by up to 64%. Our research could significantly impact the USD 38.2 billion global market of the epoxy-related industry by not only providing better thermal and mechanical performance of epoxy-based composite materials, but also simultaneously reducing the carbon footprint from the epoxy industry and relieving waste epoxy pollution.


Subject(s)
Epoxy Resins , Microalgae , Microalgae/chemistry , Epoxy Resins/chemistry , Temperature , Epoxy Compounds/chemistry , Tensile Strength
2.
Sci Prog ; 104(3): 368504211029471, 2021.
Article in English | MEDLINE | ID: mdl-34281432

ABSTRACT

Polymeric hybrid nanocomposites, due to improved mechanical, thermal, and electrical properties, are key factors in recent technologies. Because of anisotropic characteristics of polymeric hybrid nanocomposites, mechanical properties and their behavior are very difficult to predict. If they are fabricated with complicated woven fabric patterns, it becomes more difficult to predict. This review discusses in detail the properties and manufacturing methods of various fibers, focuses on different manufacturing, processing, and characterization techniques used for polymeric hybrid nanocomposites. Theoretical composite models and some recent advances in modeling and simulation techniques for polymer nanoparticle composites are discussed and thus this review can provide significant guidelines for the development of manufacturing, characterization, testing, modeling, and simulation techniques for high performance hybrid polymer nanocomposites as current state of art.

3.
Nanoscale Adv ; 1(5): 1693-1701, 2019 May 15.
Article in English | MEDLINE | ID: mdl-36134222

ABSTRACT

Preparation of high-quality boron nitride nanotubes (BNNTs) from commercially available stock is critical for eventual industry adoption and to perform comprehensive experimental studies of BNNTs. Separation of hexagonal boron nitride (h-BN) and BNNTs is a significant challenge, and equally so, quantification of h-BN content in mixed samples is a major challenge due to their nearly identical properties. This work introduces a simple method of quantifying h-BN content in BNNTs based on FTIR analysis. Quantification is achieved by "spiking" a BNNT sample with pure nanoscale h-BN as an internal standard. To demonstrate the efficacy of the quantification technique two BNNT enrichment methods, surfactant wrapping and centrifugation, and a novel sonication-assisted isovolumetric filtration are introduced. FTIR spectra of enriched samples show clear trends throughout the processes. We propose and demonstrate that FTIR peak ratios of the transverse and buckling modes of mixed h-BN/BNNT samples can be used to calibrate and quantify h-BN content in any BNNT sample. Hopefully, this method enables as-received BNNTs to be quantifiably enriched from low purity commercial feedstocks, enabling future development and study of BNNTs and related technology.

4.
Am J Cardiol ; 121(11): 1436-1440, 2018 06 01.
Article in English | MEDLINE | ID: mdl-29576234

ABSTRACT

Venous thromboembolism (VTE), including deep venous thrombosis and pulmonary embolism, is common with an annual incidence of 1 to 5 per 1,000, resulting in major morbidity, mortality, and increased health care costs. It is more common in the elderly, obese, those with cancer, those undergoing surgery, and those with previous VTE. Strategy to reduce its occurrence has important public health implications. Pleotropic effects of statins may have beneficial effects on a number of potential targets associated with VTE. Statins have excellent safety profile and seem to be associated with beneficial effects in VTE in case-control studies, large observational studies, meta-analyses, and a randomized trial. In conclusion, after critically reviewing the clinical data supporting statin use in the prevention of VTE, we presented clinical recommendations for the use of statins in reducing VTE occurrence, especially in high-risk situations.


Subject(s)
Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Pulmonary Embolism/prevention & control , Venous Thromboembolism/prevention & control , Venous Thrombosis/prevention & control , Humans
5.
Development ; 145(6)2018 03 23.
Article in English | MEDLINE | ID: mdl-29467241

ABSTRACT

Bacteria are crucial partners in the development and evolution of vertebrates and invertebrates. A large fraction of insects harbor Wolbachia, bacterial endosymbionts that manipulate host reproduction to favor their spreading. Because they are maternally inherited, Wolbachia are under selective pressure to reach the female germline and infect the offspring. However, Wolbachia infection is not limited to the germline. Somatic cell types, including stem cell niches, have higher Wolbachia loads compared with the surrounding tissue. Here, we show a novel Wolbachia tropism to polar cells (PCs), specialized somatic cells in the Drosophila ovary. During oogenesis, all stages of PC development are easily visualized, facilitating the investigation of the kinetics of Wolbachia intracellular growth. Wolbachia accumulation is triggered by particular events of PC morphogenesis, including differentiation from progenitors and between stages 8 and 9 of oogenesis. Moreover, induction of ectopic PC fate is sufficient to promote Wolbachia accumulation. We found that Wolbachia PC tropism is evolutionarily conserved across most Drosophila species, but not in Culex mosquitos. These findings highlight the coordination of endosymbiont tropism with host development and cell differentiation.


Subject(s)
Drosophila/microbiology , Polar Bodies/microbiology , Symbiosis/physiology , Viral Tropism/physiology , Wolbachia/pathogenicity , Animals , Female , Fluorescent Antibody Technique , In Situ Hybridization, Fluorescence , Oogenesis/physiology , Ovary/cytology , Ovary/microbiology
6.
Contemp Clin Dent ; 8(1): 134-138, 2017.
Article in English | MEDLINE | ID: mdl-28566865

ABSTRACT

Pycnodysostosis is an uncommon autosomal recessive sclerosing bone disorder which is characterized by short stature and generalized diffuse osteosclerosis. Patients usually have a large head with separated sutures, open fontanels, aplasia of frontal sinuses, obtuse mandibular gonial angle, and acroosteolysis of the distal phalanges. This case report showed a 25-year-old female with features pathognomonic of pycnodysostosis. The emphasis is mainly on the early diagnosis as it has an important role in the general health of such patients and prevention of complications.

7.
BMJ Case Rep ; 20162016 Sep 21.
Article in English | MEDLINE | ID: mdl-27655878

ABSTRACT

A 3-year-old girl child presented with swelling in her right lower jaw that had started 5 days previously. History revealed the child being non-immunised. Initial-evaluation revealed proptosis and bony hard swelling over the right body of the mandible. Radiological evaluation including a CT scan indicated expansile osteolytic lesion involving the body-ramus with onion-peel periosteal reaction suggesting osteomyelitis/malignancy. Blood investigations showed raised erythrocyte sedimentation rate and eosinophilia. Family screening for tuberculosis (TB) revealed that the patient, her father and siblings were PPD positive though chest screening and sputum examinations were negative in all of them. Lesion biopsy showed acute/chronic osteomyelitis with eosinophilia, tilting diagnosis towards eosinophilic granuloma/Hand-Schuller-Christian disease. Further investigations for diabetes insipidus, histiocytosis-X, skull-pelvic-femur radiographs, abdominal ultrasonography, ophthalmic consultation and PCR-TB test were negative. Histology, radiography, purified protein derivative (PPD)-positive result and history led to the diagnosis of primary TB of the mandible. Complete resolution occurred following antitubercular therapy. The case report emphasises that diagnosis of TB can sometimes be based on circumstantial evidence and positive response to antitubercular therapy even in view of a negative PCR result.

9.
J Clin Diagn Res ; 10(12): ZC54-ZC58, 2016 Dec.
Article in English | MEDLINE | ID: mdl-28209005

ABSTRACT

INTRODUCTION: Oral Submucous Fibrosis (OSMF) is a premalignant condition with potential malignant behaviour characterized by juxta-epithelial fibrosis of the oral cavity. In the process of collagen synthesis, iron gets utilized, by the hydroxylation of proline and lysine, leading to decreased serum iron levels. The trace element like iron is receiving much attention in the detection of oral cancer and precancerous condition like OSMF as it was found to be significantly altered in these conditions. AIM: The aim of this study was to compare the haemoglobin and serum iron values of OSMF subjects with that of iron deficiency anaemia subjects. MATERIALS AND METHODS: Total of 120 subjects were included, 40 subjects with the OSMF, 40 with the iron deficiency anemia without tobacco chewing habit, 40 healthy control subjects without OSMF and iron deficiency anaemia. A total of 5ml of venous blood was withdrawn from all the subjects and serum iron and haemoglobin levels were estimated for all the subjects. Estimation of iron was done using Ferrozine method and haemoglobin by Sahli's method. The statistical method applied were Kruskal Wallis, Mann Whitney and Pearson correlation coefficient test. RESULTS: There was a statistically significant difference in serum iron and haemoglobin level in all three groups (p<0.05). The serum iron level was lowest in OSMF group and haemoglobin was lowest in iron deficiency anaemia group. A progressive decrease in serum iron and haemoglobin levels from Stage I of OSMF to the Stage IV of OSMF was also observed. The iron deficiency anaemia group was not found to be suffering from OSMF in the absence of areca-nut or tobacco chewing habits, but OSMF patients with chewing habits were found to be suffering from iron deficiency anaemia. CONCLUSION: There is a progressive decrease in serum iron and haemoglobin levels from Stage I of OSMF to the Stage IV of OSMF so it can be used as an auxillary test in assessment of prognosis of the disease.

10.
Article in English | MEDLINE | ID: mdl-26697154

ABSTRACT

Ameloblastomas are tumors of odontogenic epithelial origin. The term unicystic ameloblastoma is used to describe cystic lesions with clinico-radiographic features resembling an odontogenic cyst, but histologically showing the presence of ameloblastomatous epithelium lining part of the cyst cavity. A large majority of lesions are found in the mandible, and usually cause a painless swelling of the jaws. They can be radiographically subdivided into 'dentigerous' and 'non-dentigerous' types. The unicystic ameloblastoma is believed to be less aggressive than a solid/multicystic ameloblastoma, and thus has a more favorable response to enucleation and curettage. This case report presents a case of unicystic ameloblastoma with a multilocular radiographic appearance in the anterior mandible of a 45-year-old female patient, along with a literature review of the topic.

11.
J Dent Child (Chic) ; 82(2): 108-11, 2015.
Article in English | MEDLINE | ID: mdl-26349799

ABSTRACT

Temporomandibular joint (TMJ) ankylosis is an intracapsular union of the disccondyle complex to the temporal articular surface that restricts mandibular movements, including fibrous adhesions or bony fusion between the condyle, disc, glenoid fossa, and articular eminence. The leading causes include trauma and infection. It can be a serious and disabling condition that leads to difficulties in mastication, swallowing, speaking, esthetics and oral hygiene. Disturbances of facial and mandibular growth and acute compromise of the airway invariably result in physical and psychological disability. Treatment should be initiated as soon as the condition is recognized, with the main objective of re-establishing joint function and harmonious jaw function. The purpose of this report is to describe a case of unilateral fibrous ankylosis of the right TMJ in a three-year-old girl.


Subject(s)
Ankylosis/diagnosis , Temporomandibular Joint Disorders/diagnosis , Ankylosis/surgery , Child, Preschool , Diagnosis, Differential , Female , Fibrosis , Humans , Temporomandibular Joint Disorders/surgery
12.
J Clin Diagn Res ; 9(3): ZD13-6, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25954712

ABSTRACT

Myxosarcoma is a rare malignant neoplasm of connective tissue which is characterized by tissue that resembles primitive mesenchyme, and contains relatively undifferentiated cells that show rapid growth and invasion. The cells are stellate or spindle-shaped and are present in a loose matrix which contains mucoid material, reticulum, and collagen fibers. This paper reports a rare case of a myxosarcoma of the left maxilla in a 50-year-old male, which clinically presented as a soft-tissue mass on the buccal gingiva and radiographically showed a mixed radiolucent-radiopaque appearance.

13.
J Forensic Dent Sci ; 6(2): 107-12, 2014 May.
Article in English | MEDLINE | ID: mdl-25125918

ABSTRACT

OBJECTIVE: To evaluate the diagnostic performance of X (Barr body [BB]) and Y (F body [FB]) chromosomes observed in dental pulp tissue for gender determination of an individual. MATERIALS AND METHODS: The study was carried out on 100 teeth (50 male and 50 female), which were indicated for extraction. The teeth were sectioned at various intervals (within 12 h to 49 days post-extraction), and the pulpal tissue was obtained. Two slides for each pulp tissue were prepared, one for 5% Quinacrine dihydrochloride stain (FB) and the other for Hemotoxylin and Eosin stain (BB). The slides were then observed under the fluorescent microscope for FB and under the light microscope for the BB respectively. RESULTS: Gender determination from human pulp is possible up to 7 weeks. The percentage of FB and BB decrease gradually as the time interval increases. Further, an equation was derived from the data based on the canonical discriminant function coefficients. CONCLUSION: The determination of gender based on a joint search for the presence or absence of X (BB) and Y (FB) Chromosome is a reliable and cost-effective technique.

14.
Contemp Clin Dent ; 5(2): 160-5, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24963238

ABSTRACT

OBJECTIVES: The purpose of this case series was to compare the clinical, radiographic, and histopathologic features of 11 cases of ameloblastoma that reported to the Goa Dental College and Hospital over a period of 4 years from January 2008 to December 2012. STUDY DESIGN: Data with respect to the patients' ages, sex, location of lesions, radiographic features, histopathologic features and surgical treatment and follow-up, was analyzed. RESULTS: The mean age in males was 23.25 ± 6.99 years, while that in females was 43.43 ± 17.13 years. Seven (63.63%) of the 11 subjects were females, and four (36.36%) were males. 10 (90.9%) of the 11 ameloblastomas were located in the mandible. Swelling was noted in all 11 patients. 10 cases showed radiographic findings, while one case was a peripheral soft-tissue variant. Seven (70%) of the 10 tumors were multilocular with a well-demarcated corticated border, and three cases (30%) were unilocular. Two cases showed a soap-bubble appearance. Histologically, five cases were unicystic, four were multicystic, one was desmoplastic and one was a peripheral variant. Follow-up ranged from 12 to 34 months and there were no signs of recurrence in any of the patients. CONCLUSIONS: Ameloblastomas more commonly occur in females at an older age, as compared with males. Radiographic features that could help in diagnosing ameloblastomas include its predominant occurrence in the mandible, multilocular radiolucency with well-defined, corticated, scalloped margins, expansion of buccal and lingual cortical plates, root resorption and tooth displacement.

15.
J Clin Diagn Res ; 8(3): 233-5, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24783145

ABSTRACT

AIMS AND BACKGROUND: Teeth form an excellent material for anthropological, genetic, odontologic and forensic investigations. The aim of this study was to establish the genetic control of sexual dimorphism in tooth size amongst siblings of Goan children in age range of 14-22 years. MATERIALS AND METHODS: Twenty-two sibling pairs were selected (22 males and 22 females) to assess genetic control of sexual dimorphism in tooth size. Alginate impressions were obtained for maxillary and mandibular arches and study models were prepared. Measurements were done using Zoom Digimatic Vernier Calipers with a resolution of 0.01 mm. STATISTICAL ANALYSIS: Correlation between mesiodistal and buccolingual tooth sizes amongst siblings was calculated using Pearson's correlation coefficient. RESULTS: A statistically significant association was found between Mesiodistal Widths of Permanent Maxillary Right and Left Second Molars and between Maxillary Right and Left First Premolars amongst sibling pairs. A statistically significant association was also found between Buccolingual Widths of Mandibular Right and Left First Premolars amongst sibling pairs. This statistically significant correlation found amongst siblings establishes a genetic control over sexual dimorphism in these teeth. CONCLUSION: The genetic basis of sexual dimorphism in human dentition was ascertained as a significant correlation was found between mesio-distal and bucco-lingual widths of premolars between sibling pairs.

16.
ScientificWorldJournal ; 2014: 325783, 2014.
Article in English | MEDLINE | ID: mdl-24719573

ABSTRACT

In the present study experimental and numerical investigations were carried out to predict the low velocity impact response of four symmetric configurations: 10 ply E Glass, 10 ply AS4 Carbon, and two Hybrid combinations with 1 and 2 outer plies of E Glass and 8 and 6 inner plies of Carbon. All numerical investigations were performed using commercial finite element software, LS-DYNA. The test coupons were manufactured using the low cost Heated Vacuum Assisted Resin Transfer Molding (H-VARTM©) technique. Low velocity impact testing was carried out using an Instron Dynatup 8250 impact testing machine. Standard 6 × 6 Boeing fixture was used for all impact experiments. Impact experiments were performed over progressive damage, that is, from incipient damage till complete failure of the laminate in six successive impact energy levels for each configuration. The simulation results for the impact loading were compared with the experimental results. For both nonhybrid configurations, it was observed that the simulated results were in good agreement with the experimental results, whereas, for hybrid configurations, the simulated impact response was softer than the experimental response. Maximum impact load carrying capacity was also compared for all four configurations based on their areal density. It was observed that Hybrid262 configuration has superior impact load to areal density ratio.


Subject(s)
Acceleration , Models, Theoretical , Textiles/analysis , Compressive Strength , Computer Simulation , Hardness , Materials Testing , Stress, Mechanical
17.
J Forensic Dent Sci ; 6(1): 1-2, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24696585
18.
J Forensic Leg Med ; 20(6): 788-91, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23910882

ABSTRACT

INTRODUCTION: Age estimation is a sub-discipline of the forensic sciences and an important part of every identification process, especially when information relating to the deceased is unavailable. In India, close to 3.5 million women work as commercial sex workers (CSW) of which 1.2 million are under aged. AIM: To assess the dental and the skeletal age of rescued female CSWs with an intention of rehabilitation of the minors. METHODOLOGY: Dental age assessment of 32 rescued female CSWs with unknown age was done based on the radiographic analysis using regression equations derived in a Qualitative and Quantitative study by Dinkar A D. The skeletal age was assessed based on physical and radiological examination of the skeletal bones by Forensic experts. RESULT: It was observed that the estimated age of the CSWs ranged from 7 to 22 years out of which 22 cases (68.75%) were found to be below 18 years. When the dental and skeletal age was compared the maximum variation ranged between ± 12 months (1 year). Although the CSWs were found to be from different parts of India, maximum number of the cases (50%) was from Andhra Pradesh and one case (3.13%) was from Nepal. CONCLUSION: Dental age assessment using qualitative and quantitative method given by Dinkar A D can be thought of a reliable method for dental age assessment as it didn't show much variation when compared to the skeletal age of the 32 CSWs. In the present study 68.75% of the females were minor which shows that the number of minors being trapped in the trade of prostitution is increasing. Rescuing and rehabilitation of these minors is of paramount importance.


Subject(s)
Age Determination by Teeth/methods , Sex Workers , Tooth Calcification , Tooth/diagnostic imaging , Adolescent , Age Determination by Skeleton/methods , Bone and Bones/diagnostic imaging , Child , Female , Forensic Dentistry , Humans , India , Osteogenesis , Radiography, Panoramic , Regression Analysis , Tooth Apex/diagnostic imaging , Young Adult
19.
J Phys Chem B ; 117(40): 12095-104, 2013 Oct 10.
Article in English | MEDLINE | ID: mdl-23952604

ABSTRACT

Understanding drug transportation and delivery mechanism from a molecular viewpoint is essential to find better treatment pathways. Despite the fact that many significant drugs such as anticancer doxorubicin and mitoxantrone are predominantly hydrophilic, an efficient methodology to deliver hydrophilic drug components is not well established. Here we explore this problem by studying "patchy" polymeric micelle assisted hydrophilic component transportation across a lipid membrane and delivery inside a biological lipid vesicle. Using the MARTINI force field as the basis, we study the interaction of polymeric micelle with DPPC lipid vesicles in detail. In order to facilitate hydrophilic drug transportation study, a primitive CG model for hydrophilic drug component is used. Extensive simulations carried out over hundreds of nanoseconds demonstrate successful encapsulation, transportation of hydrophilic components by patchy polymeric micelles. Results show the polymeric micelle releases a significant portion of hydrophilic contents inside the lipid vesicle. The present simulation study also reveals a possible mechanism for efficient hydrophilic component transportation and delivery. Insights from this study could potentially help the experimental community to design better delivery vehicles, especially for hydrophilic drug molecules.


Subject(s)
Lipid Bilayers/chemistry , Micelles , Polymers/chemistry , 1,2-Dipalmitoylphosphatidylcholine/chemistry , Computer Simulation , Doxorubicin/chemistry , Drug Carriers/chemistry , Hydrophobic and Hydrophilic Interactions , Mitoxantrone/chemistry , Models, Molecular
20.
J Forensic Sci ; 58(6): 1621-7, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23822559

ABSTRACT

The palatine rugae possess unique characteristics that could be used when it is difficult to identify a dead person according to fingerprints or dental records. They are permanent and unique to each person. The rugae are surrounded by cheeks, lips, tongue, and buccal pad of fat; hence, they remain protected in trauma, incineration, or mass disasters. Their pattern of orientation is formed by the 12th to 14th week of gestation and remains stable throughout life. In this study, dental casts of 120 patients were analyzed for individual rugae characteristics and strength and subsequent individual codes were given. No two individuals were having exactly matching rugae codes. Dimensions of rugae pattern, incisive papilla, and midpalatal raphe were also noted. Rugae were reevaluated after one year to check its stability, which showed no significant difference. The coding system followed can be adopted as a good and simple technique to achieve electronic transfer of the records of the palatal rugae.


Subject(s)
Palate, Hard/anatomy & histology , Adolescent , Analysis of Variance , Ethnicity , Female , Forensic Dentistry , Humans , India , Male , Models, Dental , Young Adult
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