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In the search for a “green gasoline”, a new reformulation strategy, having no or reduced amount of aromatics, is proposed. Biomass-derived alkyl levulinates (ALs) are prospected as oxygenated additives as well as blending components to circumvent the use of aromatics and methyl tertiary butyl ether (MTBE) in gasoline. By utilizing molecular dynamics (MD) simulations, the thermophysical and dynamical behavior of gasoline blends with four alkyl levulinates, viz. methyl levulinate (ML), ethyl levulinate (EL), propyl levulinate (PL), and butyl levulinate (BL), was scrutinized and compared with those of MTBE–gasoline mixtures. It is shown that, at 300 K and 1 atm, ALs in conventional gasoline can be used for reformulation with amounts up to 18 mol % while maintaining the density, viscosity, and compressibility within the recommended limits. However, this amount can be further increased to 35 mol % by modification of aromatic content. Among the studied oxygenates, BL was observed to have the lowest miscibility ...

Geometrically well-defined thin-film electrodes of Ca-doped double perovskite, PrBa0.8Ca0.2Co2O5+δ (PBCaCO), were fabricated using a spray pyrolysis system. The area specific resistance (ASR) of the electrode was calculated to be 7.1 Ω.cm2 at 973 K in air, which was observed to decrease on increasing temperature. The corresponding diffusivity of oxygen anion was calculated using molecular dynamics (MD) simulations and compared to un-doped PrBaCo2O5+δ (PBCO). At 973 K, Ca-doping did not show any improvement in the diffusivity of the PBCaCO structure, since diffusivity for the doped PBCaCO (D = 1.83 x 10-8 cm2.s-1) was comparable to the un-doped PBCO (D = 1.00 x 10-8 cm2.s-1). The improved electrochemical performance of the Ca-doped electrode was thus attributed to reduced surface segregation and henceforth better surface electrocatalytic activity.

We compare the extent to which the properties of simple liquids are pertinent to short to moderate chain n-alkanes ranging from ethane (C2) to dodecane (C12). Explicit geometric features such as bonds, angles and dihedral potentials in currently available models of n-alkanes make these systems more realistic, and distinct from the generalized Lennard-Jones chain fluids. Our study confirms that the presence of these flexible geometric constraints completely suppresses the energy-virial correlation in these systems. However, they are found to have a strong energy-virial correlation in high density region of their phase diagram when the contribution from these geometric constraints are excluded. For fluids having simple liquid like behavior, semi-quantitative relationships between structure, dynamics, and thermodynamics are well established. Range of state points is explored to test the applicability of such relationships for n-alkanes. Considering the collection of monomer beads as the reference state, thermodynamic and structural entropic measures are systematically compared with and without intramolecular contributions. We show that the pair entropy computed with explicit intramolecular geometric constraints correlates well with thermodynamic excess entropy. Both the thermodynamic and pair entropy have strong isochore dependence with reduced diffusivity. Intermolecular pair entropy correlates well with reduced diffusivity. The role of multiparticle correlations is highlighted for predicting thermodynamic and transport properties in these chain systems. Triplet correlations in addition to pair correlations are used as an attempt to improve the structural contribution to excess entropy. We show that if the three particle contribution is included in the computation of structural entropy, the resulting value overestimates the excess entropy.

Oxygen reduction reaction in a double perovskite material, PrBa

This chapter emphasizes the need for a fundamental understanding of the noncovalent interactions of amino acids with transition metal catalyst surfaces in aqueous systems. This understanding is essential for the growing development of the synthesis of bio-based fuels and chemicals using integrated fermentation and catalytic processing, wherein biogenic impurities (amino acids and protein residues) are observed to deactivate heterogeneous metal catalysts.

Liquids exhibit a sudden increase in viscosity when cooled fast enough, avoiding thermodynamically predicted route of crystallization. This phenomenon, known as glass transition, leads to the formation of non-periodic structures known as glasses. Extensive studies have been conducted on model materials to understand glass transition in two dimensions. However, despite the synthesis of disordered/amorphous single-atom thick structures of carbon, little attention has been given to glass transition in realistic two-dimensional materials such as graphene. Herein, using molecular dynamics simulation, we demonstrate the existence of glass transition in graphene leading to a realistic two-dimensional glassy structure, namely glassy graphene. We show that the resulting glassy structure exhibits excellent agreement with experimentally realized disordered graphene. Interestingly, this glassy graphene exhibits a wrinkled but stable structure, with reduced thermal vibration in comparison to its crystalline counterpart. We suggest that the topological disorder induced by glass transition governs the unique properties of this structure.

BACKGROUND: Although giant cell tumors (GCTs) are benign, their aggressiveness and tendency to recur locally challenge the orthopaedic surgeon’s ability to perform joint-preserving intralesional surgery with an acceptably low risk of local recurrence. Denosumab has emerged as a possible medical treatment of GCT because it seems to halt the progression of GCT, alleviate pain, and increase perilesional bone formation, but its exact role has been questioned, and specifically its efficacy and associated complications are not well characterized. QUESTIONS/PURPOSES: (1) Does denosumab reduce the risk of recurrence after resection or intralesional surgery? (2) What are the complications associated with the use of denosumab? METHODS: Fifty-four patients with 30 primary and 25 recurrent tumors between November 2013 and July 2016 were treated with denosumab after a confirmed histopathologic diagnosis of GCT. Another 17 patients in the same period were treated without denosumab. During the study period, we encouraged the use of denosumab in all patients except those who refused, could not afford it, or where it was contraindicated (eg, in pregnancy). In all patients undergoing intralesional surgery, we arbitrarily planned six doses before surgery. Variations in total doses before surgery were dependent on patient-related factors; in some, we gave less doses because patients expressed the inability to afford any more doses, whereas in some patients, extra doses were added when the patient wished to delay surgery as well as the because of surgeon judgment wherein in some patients, we stopped before six doses when we thought adequate bone had formed for intralesional curettage. The mean number of doses was 6.8 per patient (median, 6; range, 3-17) preoperatively. The minimum followup was 12 months (median, 27 months; range, 12-42 months). Every patient showed improvement clinically in terms of pain and halting of tumor progression within three to four doses. This was seen radiologically as a sharply defined soft tissue mass as well as hazy ossification within the tumor. For a case-matched comparison study, we identified controls as 34 patients undergoing curettage from the retrospective analysis of 68 patients curetted without denosumab between February 2010 and July 2016 matched to 25 denosumab-treated patients in terms of site, size, Campanacci grade, and recurrent versus primary status, and with a minimum 2 years followup for the control group. Fisher’s exact test was used for statistical study. Patients undergoing resection were planned for surgery after three doses of denosumab to allow the tumor to solidify and potentially decrease tumor spillage at the time of surgery. The resections could not be case-matched for comparison owing to the smaller numbers. RESULTS: We observed 14 recurrences out of the 37 curetted tumors (38%). In the case-matched analysis, 11 of 25 patients in the denosumab-treated curettage group had recurrences (44%) compared with seven of 34 (21%) in the nondenosumab-treated control group. The risk of denosumab-treated patients experiencing local recurrence as compared with the nondenosumab-treated patients was nonsignificant with a two-tailed p value of 0.085 (significance at p < 0.05) as derived from Fisher’s exact test (odds ratio, 3.03; 95% confidence interval, 0.96–9.54). There was no recurrence in the resection group. Because we do not have a control group for resection, we are unable to comment on the importance of this finding. One major complication that we observed was a recurrence with malignant transformation in a patient with a proximal humeral GCT. We did not observe any other complications related to the denosumab therapy. CONCLUSIONS: Although we could not demonstrate a higher risk of local recurrence with preoperative denosumab for intralesional surgery in the dose and frequency we administered, we advise caution in its routine use for intralesional procedures because it may be important to curette up to margins on pretreatment imaging owing to the potential residual tumor within the denosumab-mediated thick bony shell, which may result in local recurrence. We believe that denosumab treatment before resection of a large tumor aids resection without tumor spillage, particularly where important structures like the neurovascular bundle are dissected away from the tumor margin, although we cannot confirm that it helps lower the incidence of recurrence. We are concerned regarding the malignancy-causing potential from our observation in one patient as well as reports of this by others and recommend judicious use of this drug in patients with GCT. LEVEL OF EVIDENCE: Level III, therapeutic study.

Introduction. Limb salvage surgery following proximal ulna resection poses a challenge in reconstruction of the complex elbow anatomy. Various reconstruction methods described offer inadequate restoration of function and stability. Following resection of proximal ulna tumors, we aimed to restore the joint using the resected osteochondral segment of proximal ulna treated with extracorporeal irradiation and reimplantation. Questions/Purposes. (1) Does irradiated osteoarticular autograft reconstruction for proximal ulna allow anatomical joint restoration and what are the oncological and functional outcomes? (2) Is there evidence of graft-related complications or osteoarthritis at a minimum of 2 years follow-up with irradiated osteoarticular autografts for the proximal ulna? (3) How does our method of reconstruction fare as compared to reported reconstruction options in the literature? Materials and Methods. 3 patients with primary bone tumors involving the proximal ulna underwent limb salvage surgery with en bloc resection and reconstruction using the resected bone after treating it with extracorporeal irradiation of 50 Gy. Minimum follow-up of 2 years was considered for assessment of final outcomes. Radiographs were assessed for bony recurrence, union across osteotomy junction, and signs of joint arthritis. Functional outcome measures included range of movement, muscle power testing, and functional and disability scores. Results. 2 complete and 1 partial olecranon involving proximal ulnar resections were performed for three cases of Ewing’s sarcoma in 2 males and 1 female. Follow-up ranged from 28 to 42 months, and all patients continue to remain disease free. All 3 patients have achieved full range of flexion-extension and pronosupination movement in comparison to the contralateral side. Muscle power for flexion and extension was 5/5. MSTS score: 100% (30/30); MEPS score: 100; and DASH score: zero were achieved for all patients. Union across osteotomy junctions at median follow-up of 8 months without need for intervention/bone grafting was achieved. No complications related to joint laxity/subluxation, infection, graft fracture, or implant failure was noted. None of the patients have clinical or radiological signs of joint arthritis across the irradiated articulation. Conclusion. Biological restoration of elbow anatomy using osteoarticular irradiated graft for proximal ulna reconstruction offers great joint stability and functional outcomes. Although the potential risks of infection and graft failure need to be considered, reconstruction with the size-matched radiated autograft eliminates donor site morbidity, offers a low-cost alternative to endoprosthesis, and provides outcomes superior to any other methods of reconstruction as analyzed from the literature.

Density functional theory (DFT) calculations were performed to study the mechanism of carbon dioxide (CO2) reduction to carbon monoxide (CO) and methanol (CH3OH) on CeO2(110) surface. CO2 dissociates to CO on interacting with the oxygen vacancy on reduced ceria surface. The oxygen atom heals the vacancy site and regenerates the stoichiometric surface via a redox mechanism with intrinsic activation and reaction energies of 259.2 and 238.6 kJ/mol, respectively. Lateral interaction of oxygen vacancies were studied by the generation of two oxygen vacancies per unit of CeO2 surface. Compared to a single isolated vacancy, the activation and reaction energies of CO2 dissociation on a divacancy were approximately reduced to half of its value. Hydrogen atom coadsorbed on the surface was observed to assist CO2 dissociation by forming a carboxyl intermediate, CO2+H → COOH (ΔEact = 39.0 kJ/mol, ΔH = −69.2 kJ/mol) which on subsequent dissociation produces CO via the redox mechanism. On hydrogenation, CO is likely to p...

Bone sarcomas are rare tumors, approximating 0.2% of all cancers, with osteosarcoma (OGS), chondrosarcoma, and Ewing sarcoma being the most common cancers in this subset. The formation of disease management groups/clinics focused on sarcomas has resulted in better understanding and management of these uncommon tumors. Multiple large-scale retrospective data from Tata Memorial Hospital (TMH) and All India Institute of Medical Sciences have reported outcomes comparable to Western data in the field of OGS and Ewing sarcoma, with interesting prognostic factors identified for further evaluation. Soft tissue sarcomas are a rare heterogeneous group of tumors, more than 50 different tumor entities. The common subtypes identified in India include Ewing sarcoma and synovial sarcoma. Valuable work regarding brachytherapy has been done by radiation oncologists from the TMH, especially in pediatric patients.

Simulations utilizing molecular dynamics (MD) were applied to study the anisotropic diffusion in the a – b plane of double perovskite structure, GdBaCo 2 O 5.5 (GBCO 5.5 ). Diffusion coefficient of GBCO 5.5 was calculated to be 5 × 10 −8 cm 2 s −1 at 873 K. The calculated diffusion coefficient was observed to increase on increasing temperature with an activation energy of 50.8 kJ/mol. Similar MD simulations were employed to study the effect of the level of Fe doping at the B-site of the co-doped GdBa 0.5 Sr 0.5 Co 2−x Fe x O 5+ δ . In the co-doped structure, increasing diffusion was observed on increasing the Fe doping to x = 1 (D = 7.5 × 10 −8 cm 2 s −1 at 923 K). This was contrary to the Pr or Nd based co-doped materials, LnBa 1−y Sr y Co 2−x Fe x O 5+δ (Ln = Pr, Nd), where maximum diffusion was calculated for Fe doping level at x = 0.5 (D = 5.16 × 10 −8 cm 2 s −1 for Ln = Pr and D = 1.18 × 10 −7 cm 2 s −1 for Ln = Nd at 873 K). The trend in diffusivity correlates well with the trends in the measured peak power density of a solid oxide fuel cell fabricated with these electrode materials.

Nanostructured perovskite electrode materials have shown promising applications in improving the electrochemical performance of a solid oxide fuel cell (SOFC). An integrated bio and chemo-synthesis method is developed to obtain reduced particle size of layered perovskite materials. Double perovskite materials of composition GdBaCo2O5+δ was synthesized chemically and subjected to particle size reduction by using a bio-milling process[1], in which a fungal treatment was applied. Sacchromyces cerevisiae, was cultured in 250 mL YPD medium for 96 hours at 301 K. Reduced GBCO particles of sizes lesser than 20 nm were observed using HR-TEM (Figure 1a). XRD pattern confirms the presence of pure double perovskite phase in the synthesised nanoparticle of GBCO. In order to test the electro-catalytic activity of the GBCO nanoparticle, symmetric cell on gadolinium doped ceria (Gd=20%) electrolyte were fabricated using both chemically and bio-milled GBCO electrodes. The area specific resistance (ASR) for bio-milled electrode was measured by electrochemical impedance spectroscopy and was calculated to be 11.47 Ω cm2 at 873 K. The ASR was observed to decrease on increasing temperature following the Arrhenius law with an activation energy of 83 kJ/mol in the temperature range of 823-1023 K (Figure 1b). Molecular dynamics (MD) simulations were performed to study the transport of oxygen anion in GBCO (Figure 1c). The diffusion coefficient of oxygen anion in bulk GBCO was calculated to be 5 x 10-8 cm2 s-1 at 873 K. The diffusivity was found to be thermally activated with an activation energy of 50.8 kJ/mol. The diffusion coefficient in a-b plan (Figure 1d) was observed to be one order of magnitude higher as compared to the c-axis (D= 3.33 x 10-9 cm2 s-1, 873 K) indicating towards the anisotropic diffusion. The effect of iron doping at the B-site on oxygen anion diffusivity was calculated in co-doped LnBa0.5Sr0.5Co2-xFexO5+δ structures. Levels of iron doping was varied from x = 0.0, x = 0.5 to x = 1.0. The maximum diffusion was calculated for x=1.0 in GdBa0.5Sr0.5CoFeO5.5 structure. On the contrary, in PrBa0.5Sr0.5Co1.5Fe0.5O5.5 (PBSCF) and NdBa0.5Sr0.5Co1.5Fe0.5O5.5 the maximum diffusivity was calculated at x = 0.5 (Table 1). The trends in diffusivity on varying Fe doping level in LnBa0.5Sr0.5Co2-xFexO5+δ electrodes follow the same trend in their measured electrochemical performance [2]. The results thus obtained indicates that the bulk diffusion could be limiting. Experimental studies led by Choi et al. on co-doped double perovskite structures have reported a high peak power density (~2.2 W/cm2) of SOFC fabricated with a PBSCF electrode. In order to understand the effect of A- and B-site dopant on oxygen anion transport the diffusion coefficient of PBSCF was calculated by MD simulations. The diffusion coefficient of PBSCF was calculated to be 1.1 x 10-7 cm2 s-1 at 873 K (Table 1). The diffusion coefficient of PBSCF was observed to be one order of magnitude higher in comparison to the A-site doped PrBa0.5Sr0.5Co2O5.5 (8.33 x 10-8 cm2 s-1) and B-site doped PrBaCo1.5Fe0.5O5.5 (8 x 10-7 cm2 s-1) structure, calculated at 873 K [3]. References: [1] I. Uddin and P. Poddar, Int. J. Innov. Biol. Res., vol. 2, pp. 1–5, 2013. [2] S. Choi, S. Yoo, J. Kim, S. Park, A. Jun, S. Sengodan, et al. Sci. Rep., vol. 3, no. 2013, pp. 2426, 2013. [3] U. Anjum, S. Vashishtha, N. Sinha, and M. A. Haider, Solid State Ionics, vol. 280, pp. 24–29, 2015. Figure 1

BackgroundThiazide and thiazide-like diuretic agents are being increasingly used at lower doses. Hydrochlorothiazide (HCTZ) in the 12.5-mg dose remains the most commonly prescribed antihypertensive agent in the United States.ObjectivesThis study compared chlorthalidone, 6.25 mg daily, with HCTZ, 12.5 mg daily, by 24-h ambulatory blood pressure (ABP) monitoring and evaluated efficacy. Because HCTZ has been perceived as a short-acting drug, a third comparison with an extended-release formulation (HCTZ-controlled release [CR]) was added.MethodsThis 12-week comparative, double-blind, outpatient study randomized 54 patients with stage 1 hypertension to receive either chlorthalidone, 6.25 mg, (n = 16); HCTZ 12.5 mg (n = 18); or HCTZ-CR 12.5 mg (n = 20). ABP monitoring was performed at baseline and after 4 and 12 weeks of therapy.ResultsAll 3 treatments significantly (p < 0.01) lowered office BP at weeks 4 and 12 from baseline. At weeks 4 and 12, significant reductions in systolic and diastolic 24-h ambulatory and nighttime BP (p

Objective: The aim of this study was to investigate the root and canal morphology of maxillary third molars in Central India population using cone-beam computed tomography (CBCT) analysis. Materials and Methods: CBCT images of 116 maxillary third molars were observed, and data regarding the number of roots, the number of canals, and Vertucci's Classification in each root was statistically evaluated. Results: Majority of Maxillary third molars had three roots (55.2%) and three canals (37.9%). Most MB root (43.8%), DB root (87.5%), and palatal root (100%) of maxillary third molars had Vertucci Type I. Mesiobuccal root of three-rooted maxillary third molars had Vertucci Type I (43.8%) and Type IV (40.6%) configuration. Overall prevalence of C-shaped canals in maxillary third molars was 3.4%. Conclusion: There was a high prevalence of three-rooted maxillary molars with three canals.

Background: Because nearly 23,000 more neurosurgeons are needed globally to address 5 million essential neurosurgical cases that go untreated each year, there is an increasing interest in task-shifting and task-sharing (TS/S), delegating neurosurgical tasks to nonspecialists, particularly in low- and middle-income countries (LMICs). This global survey aimed to provide a cross-sectional understanding of the prevalence and structure of current neurosurgical TS/S practices in LMICs. Methods: The survey was distributed to a convenience sample of individuals providing neurosurgical care in LMICs with a Web-based survey link via electronic mailing lists of continental societies and various neurosurgical groups, conference announcements, e-mailing lists, and social media platforms. Country-level data were analyzed by descriptive statistics. Results: The survey yielded 127 responses from 47 LMICs; 20 countries (42.6%) reported ongoing TS/S. Most TS/S procedures involved emergency interventions, the top 3 being burr holes, craniotomy for hematoma evacuation, and external ventricular drain. Most (65.0%) believed that their Ministry of Health does not endorse TS/S (24.0% unsure), and only 11% believed that TS/S training was structured. There were few opportunities for TS/S providers to continue medical education (11.6%) or maintenance of certification (9.4%, or receive remuneration (4.2%). Conclusions: TS/S is ongoing in many LMICs without substantial structure or oversight, which is concerning for patient safety. These data invite future clinical outcomes studies to assess effectiveness and discussions on policy recommendations such as standardized curricula, certification protocols, specialist oversight, and referral networks to increase the level of TS/S care and to continue to increase the specialist workforce. Key words: Capacity, Global health, Global neurosurgery, LMIC, Task-sharing, Task-shifting, Workforce

Aim: To highlight radiological features and emphasize the need for tissue diagnoses to confirm bone pathology. Tuberculosis is known to present without constitutional symptoms and with unconventional imaging features mimicking sarcomas as shown in our series of 25 patients; where the imaging and biopsy protocols at our institute helped to solve these diagnostic dilemmas. Material and methods: We retrospectively analyzed clinical and radiological features and tissue diagnoses in 25 patients referred to the department of orthopedic oncology with radiological suspicion of tumor. Results: Only 7 patients had cultures positive for Mycobacterium Tuberculosis T.B. Radiological features suggestive of infection were Metaphyseal and joint involvement, permeative lesions, absence of Codman’s triangle, and soft tissue mass suggestive of a cold abscess. The predictive accuracy of the orthopedic oncologist was 60% and musculoskeletal radiologist was 72% (based on radiology). Final diagnosis is 100% confirmed on histopathology. Conclusion: Diagnosis based primarily upon imaging is a wrong approach. A multimodal approach to differentiating tuberculous bone infections from sarcomas is essential.

Introduction The major neoplastic and proliferative component of GCTB is the stromal tumor cells; that they have shown no evidence of bone destruction, instead the massive tissue destruction appears to be a result of tumor induced osteoclastogenesis. The discovery of receptor activator of nuclear factor kB (RANK) and RANK binding ligand (RANKL) uncovered the bone homeostasis and molecular mechanism by which multiple compounds (including vitamin D) regulated osteoclast differentiation; a function mediated by osteoblastic cells and osteoclast-precursor cells. Hypothesis In a country burdened by vitamin D deficiency, causal relation between hypovitaminosis D and GCTB was hypothesized based on the vitamin D mediated RANKL expression and osteoclastogenesis, as India is also a population with higher incidence of GCTB as compared to Western populations described in the literature. The possibility of vitamin D regulated osteoclastogenesis in GCTB is postulated on the evidence from molecular research linking it to the RANK/RANKL/OPG pathway. The aim of this study was to analyse the prevalence of Vitamin D deficiency in patients with primary GCTB and to elucidate any difference in serum Vitamin 25(OD)D3 levels amongst the matched control population data. Materials and results 130 patients of primary GCTBs were matched to 310 controls from the general health check population and serum levels of 25(OH)D3 were analyzed. Statistical analysis performed on the non-parametric data and Mann Whitney U Test used to derive inference with significance set at p 56 females and 76 males with median Vitamin D level in the GCTB group was 15.9 ng/ml (Mean 19.41; Range 1.03 to 92) as compared to the control population with median level of 22.2 ng/ml (Mean 25.1; Range 2.6 to 87.9). The results were significant (p value Discussion The differential expression of RANKL and OPG in response to levels of vitamin D has been established. The stromal cells of osteolytic GCTB express high levels of RANKL, which is a key signal regulator in development of this disease and bone destruction typical of GCTBs. This has resulted in research targeting this pathway for therapeutic approach in GCTBs. As vitamin D supplementation is simple and safe, increased awareness to assess and if necessary correct vitamin D status of patients is warranted, however the question as to whether patients with low vitamin D levels are more prone to develop GCTB and thus would profit from vitamin D supplementation remains unanswered. To conclude, it is essential to assess vitamin D levels in patients with GCTB as deficiency is pronounced. Future research on this hypothesis might lead to an association between Vitamin D deficiency and the onset/natural history of GCTB that may in the future help us cure or prevent GCTBs.

Aggregation of α-synuclein is closely connected to the pathology of Parkinson's disease. The phenomenon involves multiple steps, commenced by partial misfolding and eventually leading to mature amyloid fibril formation. Trehalose, a widely accepted osmolyte, has been shown previously to inhibit aggregation of various globular proteins owing to its ability to prevent the initial unfolding of protein. In this study, we have examined if it behaves in a similar fashion with intrinsically disordered protein α-synuclein and possesses the potential to act as therapeutic agent against Parkinson's disease. It was observed experimentally that samples coincubated with trehalose fibrillate faster compared to the case in its absence. Molecular dynamics simulations suggested that this initial acceleration is manifestation of trehalose's tendency to perturb the conformational transitions between different conformers of monomeric protein. It stabilizes the aggregation prone "extended" conformer of α-synuclein, by binding to its exposed acidic residues of the C terminus. It also favors the β-rich oligomers once formed. Interestingly, the total fibrils formed are still promisingly less since it accelerates the competing pathway toward formation of amorphous aggregates.

To evaluate the efficacy and safety of atorvastatin + hydroxychloroquine fixed-dose combination tablets in comparison with atorvastatin alone in treatment of dyslipidemia.This double-blind, randomized, out-patient study was conducted in 328 patients with primary dyslipidemia having low-density lipoprotein cholesterol (LDL-C) ≥ 130 mg/dL (3.37 mmol/L) to ≤ 250 mg/dL (6.48 mmol/L) and triglycerides ≤ 400 mg/dL (4.52 mmol/L). Eligible patients were randomized to receive either atorvastatin 10 mg (n = 167) or atorvastatin 10 mg + hydroxychloroquine 200 mg (n = 161) for 24 weeks.CTRI/2010/091/006138.To compare percentage change in LDL-C, total cholesterol (TC), triglycerides, high-density lipoprotein cholesterol (HDL-C) and non-high-density lipoprotein cholesterol (non-HDL-C) from baseline to Week 12 and Week 24 between groups. To compare mean change in glycated hemoglobin (HbA1c), fasting blood glucose (FBG), high-sensitivity C-reactive protein (Hs-CRP), and percentage of patients achieving lipid goals at Week 12 and Week 24.At Week 24, percentage reduction in LDL-C (-32.52 [-36.13 to -28.91] vs -39.54 [-43.25 to -35.83]; p = 0.008), TC (-24.41 [-27.10 to -21.72] vs -29.30 [-32.07 to -26.54]; p = 0.013), and non-HDL-C (-30.37 [-33.71 to -27.04] vs -36.76 [-40.18 to -33.33]; p = 0.009) was significantly greater in combination treated patients. Both the treatments showed a significant reduction in triglycerides at Week 24 from baseline, however, this reduction was not statistically significantly different between treatment groups. No significant change in HDL-C was observed in patients from both the treatment groups. At Week 24, change in HbA1c (0.22 [0.07 to 0.37] vs -0.13 [-0.28 to 0.03]; p = 0.002) and FBG was also statistically significant in favor of combination therapy (0.37 [0.07 to 0.67] vs -0.29 [-0.59 to 0.03]; p = 0.003), whereas no statistically significant difference was observed in change in Hs-CRP (p = 0.310). Significantly more patients from the combination group achieved LDL-C and TC goals. Exploratory analysis in patients with pre-diabetes showed development of diabetes in 8 patients (15.09%) from the monotherapy group and 1 patient (1.96%) from the combination group (p = 0.034). Study medications were generally safe and well tolerated.Based on study results and widely reported pleiotropic benefits, hydroxychloroquine could emerge as a potential drug for combination with statins for treatment of dyslipidemia. Long duration studies with larger sample sizes are required to further explore the role of hydroxychloroquine as adjunct to statins in reducing risk of cardiovascular events and prevention of statin-induced diabetes.

Skeletal metastasis is a common cause of severe morbidity, reduction in quality of life (QOL) and often early mortality. Its prevalence is rising due to a higher rate of diagnosis, better systemic treatment, longer lives with the disease and higher disease burden rate. As people with cancer live longer and with rising sensitivity of body imaging and surveillance, the incidence of pathological fracture, metastatic epidural cord compression is rising and constitutes a challenge for the orthopedic surgeon to maintain their QOL. Metastatic disease is no longer a death sentence condemning patients to "terminal care." In the era of multidisciplinary care and effective systemic targeted and nontargeted therapy, patient expectations of QOL, even during palliative end of care period is high. We lay emphasis on proving the diagnosis of metastasis by biopsy and histopathology and discuss imaging modalities to help estimate fracture risk and map disease extent. This article discusses at length the evidence and decision-making process of various modalities to treat skeletal metastasis. The modalities range from radiation including image-guided, stereotactic and whole body radiation, systemic targeted or hormonal therapy, spinal decompression with or without stabilization, extended curettage with stabilization, resection in select cases with megaprosthetic or biological reconstruction, percutaneous procedures using radio frequency ablation, cementoplasties and discusses the role of emerging modalities like high frequency ultrasound-guided ablation, cryotherapy and whole body radionuclide therapy. The focus lies on the role of multidisciplinary care, which considers complex decisions on patient centric prognosis, comorbidities, cost, feasibility and expectations in order to maximize outcomes on QOL issues.

Background: Mastalgia is one of the most common presenting symptoms of benign breast diseases, which may be cyclical or continuous. Mastalgia is the commonest breast symptom presenting in surgical clinics. FNAC has been employed in diagnosis of benign breast disease (BBD) doubts still exist upon its accuracy and reliability. However its accuracy has been compared to clinical examination and mammography in diagnosing BBD. To study cytomorphological findings in women aged 15-35 years suffering from cyclic mastalgia presenting to our OPD is the main objective of the present study. Methods: Women 94 in number age between 15 years-35 years of attending the outpatient department with complain of pain in breast were initially included in the study. Out of this 72 cases were deemed fit for study as they fulfilled the criteria mentioned in material and method. Results: We found that fibroadenosis alone constitutes 58.3% of all cases of cyclical mastalgia and is the most common cause of cyclical mastalgia in women presenting to OPD. Conclusions: Fibroadenosis is most common cause of cyclical mastalgia in women aged 15-35 years which is due to Hormonal disturbances unlike non-cyclical mastalgia.

In June 2011, Husk Power Systems (HPS), a social enterprise based in Bihar, Eastern India, won the prestigious Ashden Award for Sustainable Energy, considered as the "Green Oscar". Jacqueline Novogratz, Chief Executive Officer, Acumen Fund said, "Companies like HPS are working to impact positively not only the environment, but to ensure that someday everyone, including the poorest of the poor in rural India, will have access to clean and affordable electricity." HPS had plans to become a global provider of off-grid electrification and to reach out to millions of people in the underdeveloped countries. The objective of HPS was to provide a comparatively cheaper, eco-friendly, reliable power system for the poor living in the rural and remote areas of Bihar, while making sufficient profit to ensure that the business model could function smoothly in the long run.

Real-time decisions and insights over real-time data have become the essential mantra of success for many enterprises. The real-time data is generated from a multitude of sources and they come in a streaming fashion with high volume and velocity. The data could be machine generated e.g. clickstream data, logs, sensor data from IoT devices or human generated e.g. social data, mission critical transactional data. This is causing a technological shift from storage driven architectures to event driven architectures for enterprises to be able to capture, integrate and analyze these large sets of data for real-time decision making.Striim is a novel end-to-end analytics platform that enables business users to easily develop and deploy analytical applications that can generate real-time insights over real-time streaming data; business users and developers use a SQL-like declarative language (that has been extended to include streaming semantics) to write application logic in Striim. Striim provides high-throughput, low-latency event processing on commodity hardware with a scale-out architecture. In this paper, we describe the architecture of Striim and discuss some of the key aspects of the platform (a) built-in real-time data capture including streaming change data capture from transactional databases (ii) a natively built storage and query engine that uses modern data structures like skip lists to store streaming window data and performs query optimization, planning and run-time code generation (iii) enabling application de-coupling using persisted streams.

In a historic judgment the National Greens Tribunal of India has stipulated that Indian Railways should specify emission standards for diesel locomotives of Indian Railways and implement technologies to reduce these pollutants from diesel locomotives in a time bound manner. In order to decide on the emission standards, it is essential that an emission inventory of the diesel locomotives be obtained from across different areas, working environments, different configurations and age groups. Indian Railways has a population of about 5000 diesel locomotives and 56 diesel sheds and it is not possible to establish mass emission measurement systems at all diesel sheds because of the high cost of these measurement systems as well as a scientific group of personnel required for carrying out these measurements as per International standards like US EPA and Europe UIC. Both of these international emission standards stipulate mass based measurements of the pollutants in order to arrive at the emission levels of a diesel locomotive. Engine Development Directorate at Research Designs & Standards Organisation (RDSO) has setup mass emission measurement systems at RDSO for measuring emissions from test engines. At least, 100 diesel locomotives are required to be measured from different areas, configurations, age groups, etc. in order to arrive at statistically significant upper and lower control limits. It is not physically possible to bring these 100 locomotives to Engine Development Directorate at RDSO, therefore a mobile emissions test car was designed and manufactured by Indian Railways. This mobile emission test car is capable of measuring mass emissions from the diesel locomotives as per the International standards. This chapter discusses the process of how this mobile emission test car was envisaged and manufactured. This included the layout, selection of the equipments and ease of operation so as to meet the international emission measurement standards.

We introduce linguistic rough set (LRS) by integrating linguistic quantifiers in the rough set framework. The proposed LRS is inspired by the ways in which humans process imprecise information. It operates directly with the linguistic summaries and caters to imprecision implicit in the real world with partial knowledge. The measures of LRS are developed and its properties are investigated in detail. An approach is proposed for approximation of fuzzy concepts with the proposed LRS. This approach is applied in a real world case-study on the credit scoring analysis problem.

Combining established modelling techniques from multiple-criteria decision aiding with recent algorithmic advances in the emerging field of preference learning, we propose a new method that can be seen as an adaptive version of TOPSIS, the technique for order preference by similarity to ideal solution decision model (or at least a simplified variant of this model). On the basis of exemplary preference information in the form of pairwise comparisons between alternatives, our method seeks to induce an ‘ideal solution’ that, in conjunction with a weight factor for each criterion, represents the preferences of the decision maker. To this end, we resort to probabilistic models of discrete choice and make use of maximum likelihood inference. First experimental results on suitable preference data suggest that our approach is not only intuitively appealing and interesting from an interpretation point of view but also competitive to state-of-the-art preference learning methods in terms of prediction accuracy. Copyright © 2014 John Wiley & Sons, Ltd.

We use simulations and experiments to delineate the mechanism by which the addition of a small number of polar −OH groups to a nonpolar polymer increases the static relative permittivity (or dielectric constant) by a factor of 2, but more importantly while keeping the dielectric loss in the frequency regime of interest to power electronics to less than 1%. Dielectric properties obtained from experiments on functionalized polyethylenes and polypropylenes as a function of −OH doping are in quantitative agreement with one another. Molecular dynamics simulations for the static relative permittivity of “dry” −OH functionalized polyethylene (in the absence of water) are apparently in quantitative agreement with experiments. However, these simulation results would further imply that there should be considerable dielectric loss beyond simulation time scales (>0.1 μs). Since there are minimal experimentally observed dielectric losses for times as short as a microsecond, we believe that a small amount of adsorbed w...

Background & objectives: In current era of limb-salvage therapy, pasteurization of bone sarcomas is receiving growing attention as a potential extracorporeal treatment and cost-effective alternative to allografts and radiation before surgical reimplantation. Detailed in vitro and in vivo pre-clinical study to evaluate efficacy of pasteurization to eradicate malignant cells has not been reported yet. The present study was carried out to assess the efficacy of pasteurization to kill tumour cells both in vitro and in vivo. Methods: Surgically resected specimens of osteosarcomas (n=4) were cut into equal halves and one section was pasteurized by heating at 60°C to 65°C for 40 min. Paired samples before and after pasteurization were studied in vitro for DNA ploidy, evaluation of histological change and elimination of mitotic activity. These tissues were transplanted in immune-deficient NOD-SCID mice to evaluate effect on tumour-generating ability, presence of human nuclei, osteopontin and cytokine/chemokines released in tumour-transplanted mice. Results: Non-pasteurized tumour samples had viable tumour cells which exhibited significant growth in culture, increased proliferative ability and clonogenic potential while respective pasteurized tumour tissues did not grow in culture and did not exhibit clonogenicity. Flow cytometry revealed that propidium iodide positive dead cells increased significantly (P< 0.01) post pasteurization. Seven of 12 non-pasteurized tumour transplanted mice demonstrated tumour-forming ability as against 0 of 12 in pasteurized tumour transplanted mice. Solid tumour xenografts exhibited strong expression of anti-human nuclei and osteopontin by immunohistochemistry as well as secretary human interluekin-6 (IL-6) while pasteurized mice failed to express these markers. Interpretation & conclusions : This study has provided a basis to establish pasteurization as being efficacious in ensuring tumour eradication from resected bone tumour specimens. Pasteurized tumour bearing bone can thus safely be used to reconstruct large defects after tumour resection.

Introduction: One of the aims of root canal treatment is to prevent or eliminate pain. Postoperative endodontic pain control continues to be a significant challenge. Aim: To compare and evaluate the effect of single oral dose of 100 mg of tapentadol, 400 mg of etodolac, or 10 mg of ketorolac as a pretreatment analgesic for the prevention and control of postoperative endodontic pain in patients with symptomatic irreversible pulpitis. The incidence of side effects was recorded as secondary outcome. Materials and Methods: Sixty emergency patients with moderate to severe pain, diagnosed with symptomatic irreversible pulpitis were randomly allocated (1:1:1) to any of the three groups; tapentadol, etodolac, or ketorolac. Medications were administered 30 min before beginning of the endodontic treatment. Patients recorded pain intensity on 10 cm visual analog scale (VAS) after treatment, for upto 24 h. Results: At 24 h, mean ±standard deviation (SD) of VAS scores (in cm) for tapentadol, etodolac, and ketorolac were 0.89 ± 0.83, 2.68 ± 2.29, and 0.42 ± 0.69, respectively. Kruskal-Wallis (K-W) test showed significant difference among the three groups (P = 0.001). Mann-Whitney test showed significantly lower VAS scores in tapentadol and ketorolac than etodolac group (P = 0.013 and 0.001, respectively). Conclusions: Single oral dose of 10 mg of ketorolac and 100mg of tapentadol as a pretreatment analgesic significantly reduced postoperative endodontic pain in patients with symptomatic irreversible pulpitis when compared to 400 mg of etodolac.

Primary tumors of the sacrum are difficult to manage, as they often require morbid resections and complex reconstructions. In the case of tumors such as chordoma or chondrosarcoma, aggressive resections are often required to achieve appropriate margins (extending disease-free survival), followed by complex reconstructions. These reconstructions are aimed at restoring the pelvic ring and have traditionally resulted in a lumbosacral construct that utilizes structural allograft/autograft bone (fibula most commonly used) and more recently, reconstruction with 3D-printed custom sacral prostheses. While there are no reports of anatomical reconstruction using sacral allografts, extracorporeal radiation therapy (ECRT) and reimplantation provides a size and shape-matched irradiated autograft which avoids the cultural stigma, structural strength and graft-host concerns associated with allografts, as well as the high costs and time to production associated with custom 3D-printed implants. Here we present an illustrative case with technical notes, outlining the steps used at our center for ECRT. While early results with ECRT in the sacrum are promising, future larger studies should be carried out to help detect differences that may exist in long-term complications.

The concept of intuitionistic fuzzy soft set (IFSS) arising from intuitionistic fuzzy set (IFS) is generalized by including a parameter reflecting a moderator's opinion about the validity of the information provided. The resulting generalized intuitionistic fuzzy soft set (GIFSS) finds a special role in the decision making applications. It can evaluate the given criteria along with the moderator's assessment of the furnished data. The properties of GIFSS are investigated and the associated relations called generalized intuitionistic fuzzy soft relations (GIFSR) are given. A similarity measure is given to compare two GIFSSs. As this is not applicable to fuzzy numbers, a new score function is devised to compare two intuitionistic fuzzy numbers (IFNs), the components of IFS. The effectiveness of the proposed GIFSS in decision making is demonstrated on four case studies.

Tumour knee prostheses reconstruct bone gaps, left after resecting the tumour affected tissues, in limb salvage surgeries of bone cancer patients. They typically comprise of 6-12 different components chosen from a family of components that are manufactured in discrete variations (intended to cater to a wide range of patient conditions including gender, tumour position, leg (left/right), and resection length). These variations generate numerous combinations and selecting a correct set of components from a family of 100 or more total components has made the process difficult for a given patient. This article describes an adaptive probabilistic approach developed for selection of tumour knee prosthesis components, driven by geometric details. These details were extracted from the 3D virtual anatomical model, reconstructed from set of CT scan images of patients. The selection was performed in two steps. First, the grossly undersized and oversized components were eliminated. Then the geometric details of components were mapped, with the measured anatomical parameters of the patient, to form a fuzzy-logic based decision tree. This was based on pre-defined rules compiled from surgeons' experience. A set of measures (geometric difference, bone curvature, knee centre shift, and reconstruction length) were used to evaluate the selected prosthesis components. Evaluation was based on their suitability with respect to the patient's anatomy, and classified with a qualitative tag: ‘most suitable’, ‘probably suitable’, or ‘not suitable’. A case study of distal femur replacement is presented to explain the proposed methodology. This approach eliminates the risk of over and under sizing of the prosthesis components and reduces the average inventory to be maintained for each patient.

Stress–strain relationships in semicrystalline hydroxylated polyethylene are studied using all-atom molecular dynamics simulations. Chain sizes ranging from 50 to 2000 carbons are gradually cooled from melt in order to obtain semicrystalline samples for pure, 4%, and 8% hydroxylated chains. Local orientational order of the polymer backbone and hydrogen bonding behavior is studied. The effects of −OH substitution and chain length on stress–strain relationships are examined at 300 K. The number of hydrogen bonds is found to be independent of the chain length. Stress–strain relationships are generally unaffected by 4% hydroxyl substitution in long chain polyethylene. The presence of 8% −OH tends to increase the elastic limit of the material. A method for comparing semicrystalline samples of substituted and unsubstituted polymeric chains is presented by eliminating differences in alignment, distribution, and extent of crystallization.

The extent to which solvent-mediated effective interactions between nanoparticles can be predicted based on structure and associated thermodynamic estimators for bulk solvents and for solvation of single and pairs of nanoparticles is studied here. As a test of the approach, we analyse the strategy for creating temperature-independent solvent environments using a series of homologous chain fluids as solvents, as suggested by an experimental paper [M. I. Bodnarchuk et al., J. Am. Chem. Soc. 132, 11967 (2010)]. Our conclusions are based on molecular dynamics simulations of Au140(SC10H21)62 nanoparticles in n-alkane solvents, specifically hexane, octane, decane and dodecane, using the TraPPE-UA potential to model the alkanes and alkylthiols. The 140-atom gold core of the nanocrystal is held rigid in a truncated octahedral geometry and the gold-thiolate interaction is modeled using a Morse potential. The experimental observation was that the structural and rheological properties of n-alkane solvents are constant over a temperature range determined by equivalent solvent vapour pressures. We show that this is a consequence of the fact that long chain alkane liquids behave to a good approximation as simple liquids formed by packing of monomeric methyl/methylene units. Over the corresponding temperature range (233-361 K), the solvation environment is approximately constant at the single and pair nanoparticle levels under good solvent conditions. However, quantitative variations of the order of 10%-20% do exist in various quantities, such as molar volume of solute at infinite dilution, entropy of solvation, and onset distance for soft repulsions. In the opposite limit of a poor solvent, represented by vacuum in this study, the effective interactions between nanoparticles are no longer temperature-independent with attractive interactions increasing by up to 50% on decreasing the temperature from 361 K to 290 K, accompanied by an increase in emergent anisotropy due to correlation of mass dipoles on the two nanoparticles. One expects therefore that during self-assembly using solvent evaporation, temperature can be used as a structure-directing factor as long as good solvent conditions are maintained. It also suggests that disordered configurations may emerge as solvent quality decreases due to increasing role of short-range attractions and ligand fluctuation-driven anisotropy. The possibilities of using structural estimators of various thermodynamic quantities to analyse the interplay of ligand fluctuations and solvent quality in self-assembly as well as to design solvation environments are discussed.

Background/Objectives: To design a stock market prediction system using neuro-genetic approach. To predict BSE Sensex closing price using an artificial neural network. To optimize the synaptic weight values using genetic algorithm. Methods/Statistical Analysis: In this research work input parameters related to the BSE Sensex are fed as input dataset to the Multi Layer Perceptron neural network and the future day Sensex closing value is predicted as the output. Various training algorithms are implemented and the results are compared. The best neural network model is further is subjected to synaptic weight optimization using Genetic Algorithm. The various models are then subjected to testing over a period of 15 days, to obtain the most accurate model. Findings: The proposed system applies variants of Back Propagation (BP) learning algorithm on a Multi Layer Perceptron network (MLP) which is trained using four years’ BSE Sensex data. The performance of the network is measured by Normalized Mean Squared Error (NMSE). It is observed that resilient back propagation algorithm with log sigmoid activation function gives the lowest NMSE of 0.003745. The research work also uses Genetic Algorithm (GA) for weight optimization. BP suffers from the danger of getting stuck in local minima. This is avoided by using GA to select the best synaptic weights and node thresholds initially and then proceeding with the training of MLP using BP. It is observed that this hybrid model gives optimized results. In order to substantiate the model proposed, experiments are first conducted without using GA. The results of this general BP MLP model are then compared with that of GA-BP MLP model and analyzed. NMSE for the GA-BP MLP model is 0.003092121. Artificial Neural Network has evolved out to be a better technique in capturing the structural relationship between a stock’s performance and its determinant factors more accurately than many other statistical techniques. Although neural network models are used for stock prediction very little work is done on BSE SENSEX data. The proposed work is unique as experiments are done using different variants of back propagation learning algorithm and different activation functions. Therefore these experimental results add value to the existing work. The proposed work also demonstrates that performance improvement can be achieved by using genetic algorithm. Application/Improvements: The proposed model can also be used for forecasting index returns of markets like New York Stock Exchange, Hang Seng Stock Exchange, Korea Stock Exchange, Taiwan Stock Exchange etc., by using appropriate data set.

We consider data transmission through a time-selective, correlated (first-order Markov) Rayleigh fading channel subject to an average power constraint. The channel is estimated at the receiver with a pilot signal, and the estimate is fed back to the transmitter. The estimate is used for coherent demodulation, and to adapt the data and pilot powers. We explicitly determine the optimal pilot and data power control policies in a continuous-time limit where the channel state evolves as an Ornstein-Uhlenbeck diffusion process, and is estimated by a Kalman filter at the receiver. The optimal pilot policy switches between zero and the maximum (peak-constrained) value (``bang-bang'' control), and approximates the optimal discrete-time policy at low Signal-to-Noise Ratios (equivalently, large bandwidths). The switching boundary is defined in terms of the system state (estimated channel mean and associated error variance), and can be explicitly computed. Under the optimal policy, the transmitter conserves power by decreasing the training power when the channel is faded, thereby increasing the data rate. Numerical results show a significant increase in achievable rate due to the adaptive training scheme with feedback, relative to constant (non-adaptive) training, which does not require feedback. The gain is more pronounced at relatively low SNRs and with fast fading. Results are further verified through Monte Carlo simulations., 39 pages. Submitted to IEEE Transactions on Information Theory (Aug 2009)

Molecular dynamics simulations are performed to study the structure and dynamics of the LiF–BeF2 system over a range of compositions using the transferable rigid-ion model (TRIM). The densities obtained with the TRIM potential are approximately 17–20% lower than the experimental values while polarizable ion models (PIM) give densities within 5% of the experimental value. The TRIM and PIM potentials give essentially identical radial distribution functions (RDFs) for Li–F and Be–F ion pairs though the Be–Be pair correlation differ significantly and reflect the corresponding density differences. The variation in the radial distribution functions with concentration, particularly the anion–anion pair correlation function, reflects the reorganization of the fluoride ions as the addition of BeF2 in the mixture promotes the formation of the tetrahedral fluoroberyllate network. Along the 67 mole% LiF isopleth, diffusivities and Nernst–Einstein ionic conductivities from simulations using the PIM and TRIM potentials are in good agreement for temperatures up to 925 K. The viscosity data using the PIM model is also found to be in good agreement with the TRIM results presented here along the 873 K isotherm for compositions ranging from 0 to 50 mole% BeF2. The main conclusion from this study is that the non-polarizable, TRIM provides reasonable results for the structural correlations and transport properties of the LiF–BeF2 system in comparison with first-principles-based, PIM.

The relationship between local tetrahedral order, tagged particle potential energy, and coordination number is studied for mTIP3P and TIP4P models of water in the bulk as well as in the neighborhood of a small peptide. The tendency of water molecules with different binding or tagged particle potential energies to occupy environments with different degrees of disorder can be effectively illustrated by constructing tetrahedral order distributions and corresponding entropy metrics conditional on restricted ranges of local binding energy. At the state point corresponding to the onset of the density anomaly, the correlation between tetrahedral entropy versus tagged potential energy is strong and virtually identical for mTIP3P and TIP4P. In TIP4P, this correlation is retained up to temperatures as high as 300 K, while it is lost by 250 K in mTIP3P. In the 250-300 K regime that is important for biomolecular simulations, mTIP3P behaves essentially as a simple liquid while TIP4P shows the density and related anomalies characteristic of water. We also study the number of water molecules, the tetrahedral order, and the tagged molecule potential energies for water molecules as a function of the distance from the peptide for the 16-residue β-hairpin fragment of 2GB1 in mTIP3P and TIP4P solvents. The hydration shell coordination profiles (n(r)) of the number of water molecules are almost identical in the two solvents, but the radial variation in the local energies and local order show significant differences. The residue-wise variation in the tagged potential energy of water molecules within the first hydration shell is qualitatively similar in the two models. A comparison of the tetrahedral order distributions of water molecules lying at different distances from the biomolecular solute shows that the perturbation in the local tetrahedral order distributions of the bulk solvent due to the presence of the solute is marginal. Thus, in the 250-300 K regime, the mTIP3P and TIP4P water models show qualitatively different behavior in terms of the relationship between tetrahedral order and local energy, but as solvents in the neighborhood of a biomolecular solute, the differences between the two models are only quantitative and not qualitative.

Structural, density, entropy, and diffusivity anomalies of the TIP4P/2005 model of water are mapped out over a wide range of densities and temperatures. The locus of temperatures of maximum density (TMD) for this model is very close to the experimental TMD locus for temperatures between 250 and 275 K. Four different water models (mTIP3P, TIP4P, TIP5P, and SPC/E) are compared with the TIP4P/2005 model in terms of their anomalous behavior. For all the water models, the density regimes for anomalous behavior are bounded by a low-density limit at around 0.85-0.90 g cm(-3) and a high-density limit at about 1.10-1.15 g cm(-3). The onset temperatures of the density anomaly in the various models show a much greater variation, ranging from 202 K for mTIP3P to 289 K for TIP5P. The order maps for the various water models are qualitatively very similar with the structurally anomalous regions almost superimposable in the q(tet)-τ plane. Comparison of the phase diagrams of water models with the region of liquid-state anomalies shows that the crystalline phases are much more sensitive to the choice of water models than the liquid state anomalies; for example, SPC/E and TIP4P/2005 show qualitatively similar liquid state anomalies but very different phase diagrams. The anomalies in the liquid in all the models occur at much lower pressures than those at which the melting line changes from negative to positive slope. The results in this study demonstrate several aspects of structure-entropy-diffusivity relationships of water models that can be compared with experiment and used to develop better atomistic and coarse-grained models for water.

Low-cost indigenous megaprostheses used in the developing world are prone to mechanical failure but the frequency and causes are not well established.We retrospectively analyzed the causes of failure, particularly design, and suggest changes to reduce the breakage. We also report our experience with revision surgery.We identified 28 breakages in 266 megaprosthetic knee arthroplasties performed between January 2000 and December 2006. Twenty-six breakages were revised to another prosthesis. The complications were studied and the function was evaluated. Prostheses were studied for failure by the computer-aided design program SolidWorks(®) and Hyperworks(®) for finite element analysis (FEA). Design improvements were performed based on these results.In 21 cases, the failure occurred at the stem-collar junction, the point of maximum stress predicted by FEA. Stainless steel implants were prone to failure. There was one early and one late infection. Three patients died of metastatic disease. The most difficult surgical step involved the removal of the well-cemented broken stem from the intramedullary canal. Musculoskeletal Tumor Society scores varied from 27 to 29 after revision. FEA revealed stress could be reduced by filleting the stem-collar junction and by two-piece stems.Revisions of broken total knee megaprostheses, though technically difficult, have allowed patients reasonable function. We recommend design analysis for custom prostheses to point to areas of weakness. Breakages can be reduced by using titanium stems and filleting the junction or by having two-piece inserted stems. Incorporating these changes has reduced the failures in our experience.

We consider the capacity of a wideband fading channel with partial feedback, subject to an average power constraint. The channel is modeled as a set of parallel independent block Rayleigh fading subchannels with finite coherence time (L channel uses). The transmitter probes a subset of subchannels during each coherence time by transmitting pilot sequences for channel estimation. For each subchannel probed, one bit of feedback indicates whether or not the channel gain exceeds a threshold allowing transmission. Our problem is to optimize jointly the training (both length and power), number of subchannels probed (probing bandwidth), and feedback threshold to maximize the achievable rate (lower bound on ergodic capacity) taking into account the subchannel estimation error. Optimizing the probing bandwidth balances diversity against the quality of the subchannel estimate. We show that the achievable rate increases as S log L, where S is the signal-to-noise ratio, and exceeds the capacity with impulsive signaling (given by S) when L exceeds a (positive) threshold value. Moreover, the optimal probing bandwidth scales as SL/log2 L. In contrast, without feedback the optimal probing bandwidth for the probing scheme scales as SL1/3 and the achievable rate converges to S, where the gap diminishes as SL-1/3.

Background: Limb salvage in extremity tumors is now established as an oncologically safe option without compromising long-term survival. En bloc resection followed by extracorporeal radiation and reimplantation is a biological reconstruction option in diaphyseal Ewing's sarcomas. We analyzed the results of 12 cases of diaphyseal Ewing's sarcomas treated using this modality. Materials and Methods: Between March 2006 and March 2008, 12 patients with Ewing's sarcoma underwent enbloc resection and reconstruction, with reimplantation of the sterilized tumor bone, after extracorporeal irradiation. There were eight males and four females, with a mean age of 14 years (range 2 to 22 years). The femur was the most common bone involved (n=8) followed by the tibia and the humerus (two cases each). All these patients were non-metastatic at presentation and received chemotherapy as per the existing hospital protocol. The mean length of the bone resected was 20 cm (range 11 to 25 cm). The specimen was irradiated with 50 Gy prior to reimplantation and stabilized with the host bone, using suitable internal fixation. Standard biplanar radiographs were assessed for evidence of union on the follow-up visits. The functional status was assessed using the Musculoskeletal Tumor Society Scoring system at the time of the last follow up. The mean follow up duration was 29 months (range 12 to 57 months). Results: Two patients (17%) had early infection with graft removal, hence are excluded from any analysis of union, however they are included when analysing complications such as infection. Rest 10 cases were analyzed for bony union at the osteotomy sites. Sixteen (84%) of the 19 osteotomy sites united primarily, without any intervention. Implant failure and non-union was seen at three diaphyseal osteotomy sites. The average time for union of all osteotomy sites was 7.2 months (range 3 to 13 months).The average time for union of the metaphyseal osteotomy sites was 5.9 months (range 3 to 12 months) and of diaphyseal osteotomy sites was 8.3 months (range 4 to 13 months). The mean Musculoskeletal Tumor Society Score was 27 (range 19 to 30) with a mean of 27. Nine of the ten patients with lower limb involvement were independent ambulators without additional aids. At the time of the last review, six patients were free of disease and six patients had died from the disease. There were two recurrences around the operative site. Both were associated with disseminated disease and in both the recurrences were in the soft tissue, away from the irradiated graft. Conclusion: Extracorporeal irradiation is a useful, convenient technique for limb salvage in diaphyseal Ewing's sarcomas when there is reasonable residual bone stock. It is oncologically safe and has good functional results. A radiation dose of 50 Gy for sterilizing the bone ensures adequate tumor kill, while minimizing the deleterious effects on the biomechanical and biological properties of the bone. The use of appropriate implants for adequate internal fixation and supplementary bone grafting at the index surgery may help reduce the need for subsequent additional interventions to achieve union. The limitations of this procedure are that it is not applicable in tumor bones that are structurally weak and in bones with pathological fractures.

Skeletal metastasis from a cardiac myxoma is rare. We describe an extremely unusual case of a cardiac myxoma metastasing to the femur in a 46-year-old female presenting with pain in the right hip. Radiographs showed an expansile lytic lesion with pathological fracture involving the neck and proximal shaft of the right femur. Histology revealed features of cardiac myxoma with heterologous glandular elements, which was initially mistaken for a metastatic mucin-secreting adenocarcinoma.