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21.
Rahul Ramesh Nair Moni Mohan Mondal Shanmugham Venkatachalam Srinivasan Dirk Weichgrebe 《Materials》2022,15(12)
Synthesizing biochar from mineral- and ash-rich waste biomass (MWB), a by-product of human activities in urban areas, can result in renewable and versatile multi-functional materials, which can also cater to the need of solid waste management. Hybridizing biochar with minerals, silicates, and metals is widely investigated to improve parent functionalities. MWB intrinsically possesses such foreign materials. The pyrolysis of such MWB is kinetically complex and requires detailed investigation. Using TGA-FTIR, this study investigates and compares the kinetics and decomposition mechanism during pyrolysis of three types of MWB: (i) mineral-rich banana peduncle (BP), (ii) ash-rich sewage sludge (SS), and (iii) mineral and ash-rich anaerobic digestate (AD). The results show that the pyrolysis of BP, SS, and AD is exothermic, catalyzed by its mineral content, with heat of pyrolysis 5480, 4066, and 1286 kJ/kg, respectively. The pyrolysis favors char formation kinetics mainly releasing CO2 and H2O. The secondary tar reactions initiate from ≈318 °C (BP), 481 °C (SS), and 376 °C (AD). Moreover, negative apparent activation energies are intrinsic to their kinetics after 313 °C (BP), 448 °C (SS), and 339 °C (AD). The results can support in tailoring and controlling sustainable biochar synthesis from slow pyrolysis of MWB. 相似文献
22.
23.
Pannu KK Chadha S Kumar D Preeti 《Indian journal of otolaryngology and head and neck surgery》2011,63(3):208-213
To evaluate and analyse the hearing loss in tympanic membrane perforation based on size, site and duration of perforation. The material for this study was comprised of 100 patients of either sex and of age 15?years and above selected randomly. Size of tympanic membrane perforation was assessed under microscope using calibrated wire look. Patients were divided into three groups according to size; group I (0-9?mm(2)), Group II (9-30?mm(2)), Group III (≥?30?mm(2)); according to site into anterior and posterior group; according to involvement of malleus into malleolar and non malleolar and according to duration into Group A (<1?year), Group B (1-5?years), Group C (≥?5?years). Hearing loss was measured in each case with pure tone audiometry. Data was analysed statistically using paired t-test. Hearing loss increased as the perforation size increased [I vs. II (t?-?4.23, p?0.001), II vs. III (t?-?8.19, p?0.001), I vs. III (t?-?11.68, p?0.001)]. Hearing loss was more in posterior quadrant perforation than anterior quadrant perforation but difference was not significant statistically (t?-?1.15, p?>?0.05). Hearing loss was more in malleolar perforation (t?-?5.74, p?0.001). Hearing loss increased as the duration of disease increased [A vs. B (t?-?2.01, p?0.043), A vs. C (t?-?5.49, p?0.001), B vs. C (t?-?4.14, p?0.001)]. 相似文献
24.
Vertical rectus abdominis mycutaneous (VRAM) flap provides a reliable flap cover for large soft tissue defects of chest wall, torso, groin, perineum and thigh. It has been mainly used in trauma and benign conditions. Between January 1994 through January 1999, eight patients with locally advanced malignant tumors underwent radical resection and reconstruction using pedicled VRAM flap. Inferiorly based VRAM flap was used in five patients and superiorly based VRAM flap in three patients. Defect size ranged from 144 to 900 CM2. (mean 386 cm2). Average blood loss for combined resection and reconstruction was 600ml. (range 400-800 ml.) Primary closure of both donor and recipient sites achieved in all patients. There was no wound infection, flap necrosis or abdominal hernia. There patients received postoperative radiotherapy and chemotherapy and two patients received radiotherapy only. All the the patients are alive and free of local recurrence at mean follow up 32 months. Results of our study shows that VRAM flap is versatile and sturdy flap with a wide are of rotation and it can reach diverse anatomical sites like torso, chestwall, thigh and perineum to cover large defects following radical resection for tumors. 相似文献
25.
Lee JJ Shetty D Lee YS Kim SE Kim YJ Hong MK Son JY Jeong JM 《Nuclear medicine and biology》2012,39(3):325-333
PurposeWe evaluated new 111In-labeled amino acid derivatives, in which the amino acids are conjugated with1,4,7,10-tetra-azacyclododecane-1,4,7,10-tetraacetic acid (DOTA), 1,4,7,10-tetraazacyclododecane-1,7-diacetic acid (DO2A) or 1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid (DO3A).MethodsDOTA-aminoalanine (DOTA-A), DOTA-aminohomoalanine (DOTA-H), DOTA-lysine (DOTA-L), DO2A-alanine (DO2A-A), DO3A-alanine (DO3A-A) and DO3A-homoalanine (DO3A-H) were labeled with 111In. In vitro cell uptake assays were performed usingHep3B (a human hepatoma cell line), CT26 (a mouse colon cancer cell line) and U87MG (a human glioma cell line). In vitro cell uptake inhibition assays were performed using U87MG and 111In-DO3A-H. U87MG bearing xenografted mice were subject to biodistribution, SPECT imaging, autoradiography, and immunohistochemistry studies.ResultsOf the amino acid derivatives and cell lines examined, U87MG and 111In-DO3A-H showed highest uptake in vitro. This uptake was blocked by 2-aminobicyclo-[2,2,1] heptane-2-carboxylic acid (BCH) and by tryptophan. 111In-DO3A-HSPECT imaging of U87MG bearing xenografted mice visualized tumors (mean tumor-to-muscle ratio 3.16±0.74). Autoradiography and immunohistochemistry revealed that 111In-DO3A-H uptake matched L-type amino acid transporter 1 expression.ConclusionTumor uptake was successfully imaged using 111In-DO3A-H in U87MG bearing xenografted mice. 111In-DO3A-H appears to be useful for imaging tumors expressing L-type amino acid transporter. 相似文献
26.
Kadarkarai Murugan Narayanan Aarthi Kalimuthu Kovendan Chellasamy Panneerselvam Balamurugan Chandramohan Palanisamy Mahesh Kumar Duraisamy Amerasan Manickam Paulpandi Ramachandran Chandirasekar Devakumar Dinesh Udaiyan Suresh Jayapal Subramaniam Akon Higuchi Abdullah A. Alarfaj Marcello Nicoletti Heinz Mehlhorn Giovanni Benelli 《Parasitology research》2015,114(10):3657-3664
27.
Dutta P Mitra U Manna B Niyogi SK Roy K Mondal C Bhattacharya SK 《Archives of disease in childhood》2001,84(3):237-240
AIMS—To compare the clinical
efficacy of hypo-osmolar oral rehydration salt (ORS) solution (224 mmol/l) and standard ORS solution (311 mmol/l) in severely malnourished
(marasmic) children having less than 60% Harvard standard weight for
age with dehydrating acute watery diarrhoea.
METHODS—In a double blind, randomised, controlled trial, 64 children aged 6-48 months were randomly assigned standard (n = 32) or hypo-osmolar ORS (n = 32).
RESULTS—Stool output (52.3 v 96.6 g/kg/day), duration of diarrhoea (41.5 v 66.4 hours), intake of ORS (111.5 v 168.9 ml/kg/day), and fluid intake (214.6 v 278.3 ml/kg/day) were significantly less in the hypo-osmolar group than in the standard ORS group. Percentage of weight gain on recovery in the hypo-osmolar group was also significantly less (4.3 v 5.4% of admission weight) than in the standard ORS group. A total of 29 (91%) children in the standard ORS group and 32 (100%) children in the hypo-osmolar group recovered within five days of initiation of therapy. Mean serum sodium and potassium concentrations on recovery were within the normal range in both groups.
CONCLUSION—Our findings suggest that hypo-osmolar ORS has beneficial effects on the clinical course of dehydrating acute watery diarrhoea in severely malnourished (marasmic) children. Furthermore, children did not become hyponatraemic after receiving hypo-osmolar ORS.
相似文献
METHODS—In a double blind, randomised, controlled trial, 64 children aged 6-48 months were randomly assigned standard (n = 32) or hypo-osmolar ORS (n = 32).
RESULTS—Stool output (52.3 v 96.6 g/kg/day), duration of diarrhoea (41.5 v 66.4 hours), intake of ORS (111.5 v 168.9 ml/kg/day), and fluid intake (214.6 v 278.3 ml/kg/day) were significantly less in the hypo-osmolar group than in the standard ORS group. Percentage of weight gain on recovery in the hypo-osmolar group was also significantly less (4.3 v 5.4% of admission weight) than in the standard ORS group. A total of 29 (91%) children in the standard ORS group and 32 (100%) children in the hypo-osmolar group recovered within five days of initiation of therapy. Mean serum sodium and potassium concentrations on recovery were within the normal range in both groups.
CONCLUSION—Our findings suggest that hypo-osmolar ORS has beneficial effects on the clinical course of dehydrating acute watery diarrhoea in severely malnourished (marasmic) children. Furthermore, children did not become hyponatraemic after receiving hypo-osmolar ORS.
相似文献
28.
Mendelsohn AH Sung MW Berke GS Chhetri DK 《The Annals of otology, rhinology, and laryngology》2007,116(2):85-91
The clinical diagnosis of superior laryngeal nerve paralysis (SLNp) is infrequently made, because of the heterogeneity of clinical presentations and laryngoscopic findings. Laryngeal electromyography (LEMG) can provide the definitive diagnosis of this abnormality. With increasing use of LEMG in clinical practice, this condition is now more frequently appreciated by otolaryngologists. A characteristic, but infrequently reported, videostroboscopic vocal fold motion termed Gegenschlagen ("dashing-against-each-other") has previously been described to occur in unilateral SLNp. We encountered such motion in a clinical case, which we subsequently verified as unilateral SLNp by means of LEMG. This characteristic glottic motion was then verified in an in vivo canine model of phonation after unilateral SLNp. Videostrobokymography was performed to generate kymograms that illustrated this vocal fold motion clearly. Kymograms of both human and canine subjects with SLNp demonstrated an undulating motion of the horizontally shifting glottic space as the medial edges of the vocal folds chased each other 90 degrees out of phase. As one vocal fold mucosal edge was opening, the other was closing, and this repeated motion appeared as vocal folds chasing or dashing against each other. Although not uniformly seen in all cases, this vocal fold motion appears to be unique to SLNp. 相似文献
29.
Paolo Rinaudo Shehua Shen Jia Hua Su Qian Uday Prabhu Erwin Garcia Marcelle Cedars Dinesh Sukumaran Thomas Szyperski Chris Andrews 《Journal of assisted reproduction and genetics》2012,29(12):1435-1442
Background
Identification of a non-invasive technique to assess embryo implantation potential in assisted reproduction would greatly increase success rates and lead more efficiently to single embryo transfer. Early studies suggested metabonomic analysis of spent culture media could improve embryo selection. The goal of this study is to assess if embryo implantation can be predicted based on proton nuclear magnetic resonance (1H NMR) profiles of spent embryo culture media from patients undergoing transfer of multiple embryos on cycle day 3.Method
We conducted a retrospective study in an academic assisted reproduction technology (ART) program and analyzed the data in a university research center. Two hundred twenty-eight spent culture media samples originating from 108 patients were individually analyzed. Specifically, five distinct sets (1 to 5) of different types of spent media samples (volume ~14 μL) from embryos that resulted in clinical pregnancy (positive heart rate at 6 weeks gestation) (n1 = 29; n2 = 19; n3 = 9; n4 = 12; n5 = 33; ntotal = 102) and from embryos that did not implant (n1 = 28; n2 = 29; n3 = 18; n4 = 15; n5 = 36; ntotal = 126) were collected on day 3 of embryo growth. The media samples were profiled using 1H NMR spectroscopy, and the NMR profiles of sets 1 to 5 were subject to standard uni- and multi-variate data analyses in order to evaluate potential correlation of profiles with implantation success.Results
For set 1 of the media samples, a borderline class separation of NMR profiles was obtained by use of principal component analysis (PCA) and logistic regression. This tentative class separation could not be repeated and validated in any of the other media sets 2 to 5.Conclusions
Despite the rigorous technical approach, 1H NMR based profiling of spent culture media cannot predict success of implantation for day 3 human embryos.Electronic supplementary material
The online version of this article (doi:10.1007/s10815-012-9877-9) contains supplementary material, which is available to authorized users. 相似文献30.
Dinesh D 《Journal of paediatrics and child health》2005,41(9-10):504-507
Until recently, all babies born in Wellington had umbilical cord blood sampling for direct antiglobulin test (DAT). It is considered to be an important test in identifying babies who are at risk of haemolytic disease of the newborn (HDN). OBJECTIVE: The aim of this review was to examine the utility of positive DAT results and ascertain: -- How many cases required phototherapy? -- Were any babies readmitted for phototherapy? -- Did the positive DAT influence the detection and treatment of HDN? METHODS: The clinical records of all newborn babies found to have positive DATs by Wellington Hospital Blood Bank, over a 6-month period (January 2001-June 2001) were reviewed. Blood group serological results of all babies that received phototherapy during this period were also reviewed. RESULTS: Ninety-four babies had a positive DAT, of which 22 (23%) received phototherapy. The incidence of a positive cord blood DAT was found to be 5.5%. In total, 1724 cord blood samples were analysed by Blood Bank over the first 6 months in 2001. Overall 145 babies received phototherapy, 117 were DAT-negative and six were not tested. Six of the 22 (27%) DAT-positive babies that received phototherapy were alerted by a positive DAT, leading to measurement of serum bilirubin (SBR). Twelve of the 22 (55%) were initially alerted by clinical jaundice, leading to measurement of SBR. Two DAT-positive cases were diagnosed antenatally, both were due to anti-D. Overall 10 babies were readmitted for phototherapy, two had a positive DAT. One baby received an exchange transfusion in addition to phototherapy. Two babies that received phototherapy had SBRs in the exchange transfusion range. Eighty-six per cent of the DAT-positive cases treated with phototherapy were due to anti-A. There were four cases of DAT-negative ABO HDN. CONCLUSIONS: The positive predictive value of a positive DAT for HDN is 23%. The sensitivity was estimated to be 86%. Ten babies required readmission for phototherapy, two of these were DAT-positive. Jaundice, rather than the positive DAT, was the first alert in the majority of cases of HDN requiring phototherapy. Recommendations for testing are discussed but remain controversial in practice. Assessment for hyperbilirubinaemia in all infants early in life is fundamental. 相似文献