Galactic Escape Speeds in Mirror and Cold Dark Matter Models

The mirror dark matter (MDM) model of Berezhiani et al. has been shown to reproduce observed galactic rotational curves for a variety of spiral galaxies, and has been presented as an alternative to cold dark matter (CDM) models. We investigate possible additional tests involving the properties of stellar orbits, which may be used to discriminate between the two models. We demonstrate that in MDM and CDM models fitted equally well to a galactic rotational curve, one generally expects predictable differences in escape speeds from the disc. The recent radial velocity (RAVE) survey of the Milky Way has pinned down the escape speed from the solar neighbourhood to $v_{esc}=544^{+64}_{-46}$ km s$^{-1}$, placing an additional constraint on dark matter models. We have constructed an MDM model for the Milky Way based on its rotational curve, and find an escape speed that is just consistent with the observed value given the current errors, which lends credence to the viability of the MDM model. The Gaia-ESO spectroscopic survey is expected to lead to an even more precise estimate of the escape speed that will further constrain dark matter models. However, the largest differences in stellar escape speeds between both models are predicted for dark matter dominated dwarf galaxies such as DDO 154, and kinematical studies of such galaxies could prove key in establishing, or abolishing, the validity of the MDM model.Comment: Accepted for publication in the European Physical Journal

Egg Batch Size of the Carambola Fruit Fly, Bactrocera Sp (Malaysian A) (Diptera Tephritidae)

The mean egg batch size for Bactrocera Malaysian A under[zeld and laboratory conditions was respectively 4.67 ± 0.40 (range 1 - 25) and 4.18± 0.26 (range 1-24). More single egg batches were observed in the field (22.0% of the total batches examined) compared to 7.5% in the laboratory. In both cases the mode was at 2 eggs, with batch size of 8 or more eggs fewer in number. It is suggested that such an uneven egg distribution would increase egg survival from parasitism, if the optimal foraging models apply and the egg parasite oviposits only in high egg batches

A priori prediction of aggregation efficiency and rate constant for fluidized bed melt granulation

This paper presents a predictive aggregation rate model for spray fluidized bed melt granulation. The aggregation rate constant was derived from probability analysis of particle–droplet contact combined with time scale analysis of droplet solidification and granule–granule collision rates. The latter was obtained using the principles of kinetic theory of granular flow (KTGF). The predicted aggregation rate constants were validated by comparison with reported experimental data for a range of binder spray rate, binder droplet size and operating granulator temperature. The developed model is particularly useful for predicting particle size distributions and growth using population balance equations (PBEs)

Maternal child feeding knowledge and practices and growth status of young children aged 6 to 24 months in Kuala Lumpur

This study was conducted to determine the association between maternal child feeding knowledge and practices with the growth status of young children. A total of 102 young children (62 boys and 40 girls) aged between 6 and 24 months old and their mothers participated in this study. A set of structured questionnaire; was used to obtain information on socio-economic, demographic characteristics, maternal feeding knowledge and practices, and anthropometric measurements of the young children. Maternal feeding knowledge was assessed in three different constructs i.e. general nutrition, breastfeeding and complementary feeding. Maternal feeding practice was assessed by examining whether mothers met the WHO guidelines for continued breastfeeding or feeding of milk or milk products, number of feeding times and number of food groups. Anthropometric measurements of the children such as weight and recumbent length were obtained using TANITA weighing scale and wooden measuring board, respectively. The anthropometric measurements were then compared to the National Center for Health Statistics (NCHS) reference. The results indicated that 18.6% (n=19) of the young children were significantly underweight, 16.7% (n=17) mildly underweight, and 3.9% (n=4) were overweight. The percentage of children with significant and mild wasting were 17.6% (n=18) and 32.4% (n=33) respectively, while 14.7% (n=15) and 34.3 (n=35) were significantly and mildly stunted respectively. Maternal feeding data showed that the mean of maternal feeding knowledge score in the three constructs were 6.73±0.18, 5.97±0.19 and 6.57±0.18, for general nutrition, breastfeeding and complementary feeding respectively. The total score for each construct was 10. The mean total knowledge score obtained was 19.26±4.12. Maternal feeding practice data indicated that 97.1% (n=99) of the mothers continued breastfeeding or feeding milk or milk products, 33.3% (n=34) of the children were fed the recommended minimum number of times, and 81.4% (n=83) of the children were fed the recommended minimum number of food groups. Statistical test on the association between maternal child feeding knowledge and practices with the growth status of young children will be further conducted. Maternal nutritional knowledge and child feeding practices should not be overlooked as factors that may influence growth status of young children

XRD analysis of Cu-Al interconnect intermetallic compound in an annealed micro-chip

Cu-Al intermetallic compound (IMC) in Cu wire-Al bond pad interconnect interface is drawing attention of researches. However, due to thin IMC thickness, the characterizations of the IMC are limited to expensive and time consuming techniques. An evaluation is performed to use common X-Ray Diffraction (XRD) technique to identify the IMC in the Cu wired micro-chip samples in powder form. Existence of mixture of CuAl and CuAl2 was first confirmed by transmission electron microscope (TEM) and energy dispersive X-ray (EDX). In XRD analysis, peak correspond to CuAl phase is identified from measurement with slower scan configuration. The difficulty for IMC peak detection in diffractogram is due to low composition ratio of IMC relative to other materials available in the sample. KOH treatment for enhancing IMC peaks intensity does not work as expected as it etches the IMC as well

Adjuvant Migraine Medications in the Treatment of Sudden Sensorineural Hearing Loss.

Objectives/hypothesisTo examine the hearing outcomes of patients with sudden sensorineural hearing loss (SSNHL) treated with oral and intratympanic (IT) steroid only or a combination of steroid and migraine treatment. Our hypothesis was that adjuvant migraine medications may improve outcomes in SSNHL.MethodsA retrospective chart review at a tertiary otology center was conducted to identify patients with SSNHL who received oral steroid and IT dexamethasone injection(s) with or without migraine medications (a combination of nortriptyline and topiramate).ResultsA total of 47 patients received oral steroid and IT dexamethasone injection(s) only, and 46 patients received oral steroid and IT dexamethasone injection(s) as well as migraine lifestyle changes plus a combination of nortriptyline and topiramate. There were no significant differences in demographics and baseline audiometric data between the two groups. Both groups demonstrated improvements in pure tone average (PTA) and hearing thresholds at 250 Hz and 8000 Hz posttreatment. However, compared to steroid-only group, the adjuvant migraine medications group had significantly greater improvements in hearing thresholds at the lower frequencies (250 Hz, 500 Hz, 1000 Hz). Patients in the latter cohort also had greater improvement in PTA (P = .01) and received fewer IT injections (P = .04) PTA improvement of ≥ 10 dB was observed in 36 patients (78%) in the adjuvant migraine medications group and 22 patients (46%) in the control group (P < .001).ConclusionIn multimodal treatment of SSNHL, supplementing oral and IT steroid with migraine medications may result in greater improvements in lower frequency hearing thresholds and PTA. Furthermore, adjuvant migraine treatment can lead to decrease in number of IT injections, thus reducing procedure-related risks and complications.Level of evidence3 Laryngoscope, 131:E283-E288, 2021

Phenomenological constraints on minimally coupled exotic lepton triplets

By introducing a set of new triplet leptons (with nonzero hypercharge) that can Yukawa couple to their Standard Model counterparts, new sources of tree-level flavor changing currents are induced via mixing. In this work, we study some of the consequences of such new contributions on processes such as the leptonic decays of gauge bosons, $\ell \rightarrow 3\ell'$ and $\ell \rightarrow \ell' \gamma$ which violate lepton flavor, and mu-e conversion in atomic nuclei. Constraints are then placed on the parameters associated with the exotic triplets by invoking the current low-energy experimental data. Moreover, the new physics contribution to the lepton anomalous magnetic moments is calculated.Comment: 17 pages, 1 figure, 2 tables (REVTeX4.1); v2: refs added, to appear in PR

Memory difference control of unknown unstable fixed points: Drifting parameter conditions and delayed measurement

Difference control schemes for controlling unstable fixed points become important if the exact position of the fixed point is unavailable or moving due to drifting parameters. We propose a memory difference control method for stabilization of a priori unknown unstable fixed points by introducing a memory term. If the amplitude of the control applied in the previous time step is added to the present control signal, fixed points with arbitrary Lyapunov numbers can be controlled. This method is also extended to compensate arbitrary time steps of measurement delay. We show that our method stabilizes orbits of the Chua circuit where ordinary difference control fails.Comment: 5 pages, 8 figures. See also chao-dyn/9810029 (Phys. Rev. E 70, 056225) and nlin.CD/0204031 (Phys. Rev. E 70, 046205

Time scale analysis for fluidizedbedmeltgranulation III: binder solidification rate

In series I and II of this study ([Chua et al., 2010a] and [Chua et al., 2010b]), we discussed the time scale of granule–granule collision, droplet–granule collision and droplet spreading in Fluidized Bed Melt Granulation (FBMG). In this third one, we consider the rate at which binder solidifies. Simple analytical solution, based on classical formulation for conduction across a semi-infinite slab, was used to obtain a generalized equation for binder solidification time. A multi-physics simulation package (Comsol) was used to predict the binder solidification time for various operating conditions usually considered in FBMG. The simulation results were validated with experimental temperature data obtained with a high speed infrared camera during solidification of ‘macroscopic’ (mm scale) droplets. For the range of microscopic droplet size and operating conditions considered for a FBMG process, the binder solidification time was found to fall approximately between 10-3 and 10-1 s. This is the slowest compared to the other three major FBMG microscopic events discussed in this series (granule–granule collision, granule–droplet collision and droplet spreading)

Compound C prevents Hypoxia-Inducible Factor-1α protein stabilization by regulating the cellular oxygen availability via interaction with Mitochondrial Complex I

The transcription factor Hypoxia-Inducible Factor-1α is a master regulator of the cellular response to low oxygen concentration. Compound C, an inhibitor of AMP-activated kinase, has been reported to inhibit hypoxia dependent Hypoxia-Inducible Factor-1α activation via a mechanism that is independent of AMP-activated kinase but dependent on its interaction with the mitochondrial electron transport chain. The objective of this study is to characterize the interaction of Compound C with the mitochondrial electron transport chain and to determine the mechanism through which the drug influences the stability of the Hypoxia-Inducible Factor-1α protein