bluuebunny/crossref_metadata_2025 huggingface dataset:
Chemical Modification of Chitosan in order to Inverse Swelling Behavior: Comparison between Crosslinking, Michael Addition and Graft Copolymerization Reactions
Authors: Zakhireh Solmaz , Mahkam Mehrdad , Toomari Yousef , Jafarirad Saeed
Published: July 2015

In the present work, three methods were used to inverse chitosan swelling behavior including, conjugation of p-amino benzoic acid (PABA) on cross-linked chitosan in different condition, Michael addition reaction of acrylic acid (AA) on chitosan and finally graft copolymerization of methacrylic acid (MMA) on chitosan. We couldnt inverse chitosan swelling behavior by the Michael addition reaction of acrylic acid, but conjugation of PABA on cross-linked chitosan inversed the chitosan swelling behavior. In addition, the graft copolymerization of MMA on chitosan was also successful. In general, the third method, among the above-mentioned modifications provided the best results.Bangladesh Pharmaceutical Journal 18(2): 110-117, 2015
In vitro and in vivo Antiamoebic Potential of Actinopyga lecanora (Jaeger)
Authors: Lakshmi Vijai , Ghosal Sheela
Published: July 2015

Human amoebiasis, due to Entamoeba histolytica infection, is mainly associated with morbidity thus affecting the quality of life and pace of development in the countries with warm climatic conditions. So far, the available drugs provide only symptomatic relief and they are not devoid of side effects. This leads to obtain novel molecules from natural sources having antiamoebic activity. The methanol extract of Actinopyga lecanora (Jaeger) displayed antiamoebic activity. It showed MIC 125 ?g/ml in our in-vitro studies, but when it was tested in rats, it revealed 88% inhibition of trophozoites at the dose of 900 mg/kg body weight against Entamoeba histolytica. Further work is in progress for the isolation and characterization of active molecules.Bangladesh Pharmaceutical Journal 18(2): 118-120, 2015
Antibiotic Sensitivity of Staphylococcus aureus and Staphylococcus epidermidis Isolated from Acne Patients
Authors: Khan Ashfia Fatima , Hana Humayera Kabir , Sheak Jakaria , Begum Kohinur
Published: July 2015

In this study, twenty five samples were collected from acne, ranging from 20 to 25 years old patients. The specimens were cultured on trypticase soy agar (TSA) plate. 25 suspected single colonies were isolated using mannitol salt agar. Isolates were identified by short biochemical tests such as catalase, coagulase, oxidase and Gram staining test. Five Staphylococcus aureus and eleven Staphylococcus epidermidis strains were identified. Antibiotic sensitivity of all strains was tested according to the Kirby-Bauer method using commercially available gentamicin, erythromycin, azithromycin, oxacillin, clindamycin and rifampicin discs. 100% of the isolates were sensitive to gentamicin and rifampicin. On the other hand, 93.75% isolates were sensitive to oxacillin, erythromycin and azithromycin and 81.25% isolates were sensitive to clindamicin. Minimum inhibitory concentration (MIC) of rifampicin and gentamicin was determined by test tube serial dilution method and it was found to be 4 ?g/ml for both. Our results showed that both rifampicin and gentamicin are effective antibacterial agents for acne.Bangladesh Pharmaceutical Journal 18(2): 121-125, 2015
Development and Evaluation of Salbutamol Sulphate Loaded Ethyl Cellulose Microcapsules using Emulsion Solvent Evaporation Technique
Authors: Alam Md Shamsul , Chowdhury Jakir Ahmed , Sadat Sams Mohammad Anowar , Reza Md Selim
Published: July 2015

Ethyl cellulose (EC) microcapsules containing Salbutamol sulphate (SS) were prepared through emulsion-solvent evaporation technique. Microcapsules were compressed and in-vitro release profiles were studied from both microcapsules and their compressed matrix tablets. Different amounts of drug were added in order to obtain various drugs to polymer ratios and it was found that the size of microcapsules reduced with the increase in core loading. In the preparation of formulations, Tween 80 was used as an emulsifying or dispersing agent and light liquid paraffin (LLP) was used as oil phase. The in-vitro release of EC microcapsules was studied in distilled water at 37º ± 0.5°C. A biphasic release behavior of SS from microcapsules was observed. In case of microcapsules, an immediate release was observed but for their compressed tablet form, initially a burst effect and then slow release were observed which was extended for 8 hours. In order to further investigate the type of drug release mechanism, the dissolution data were plotted according to the different kinetic models. In-vitro dissolution studies showed that zero-order and square-root of time (Higuchi model) release characteristics were exhibited.Bangladesh Pharmaceutical Journal 18(2): 132-136, 2015
A Survey of the Role of Community Pharmacists in Dhaka city, Bangladesh
Authors: Rakib Abdur , Sarwar Md Shahid , Zannah Shaheda , Khanum Sayema , Rashid Mamunur
Published: July 2015

Community pharmacists play a vital role in improving medication safety and better healthcare facility to the community. Unfortunately, the field of community pharmacy in Bangladesh is still to be developed and there is scarcity of data regarding current role of community pharmacists in Bangladesh. The present study was conducted to find out the role of community pharmacists in Bangladesh. For the study purpose, we visited 42 retail pharmacies in Banani, Khilkhet and Uttra areas of Dhaka city and interviewed the community pharmacists working there. We found that there were total 50 community pharmacists in 42 retail pharmacy and also observed that most of the pharmacists (64%) worked alone. Interestingly, we didnt find a single A-grade pharmacist working as community pharmacist. B-grade pharmacists who completed a 3 year diploma in pharmacy were only 4 in number and 92% of them were C-grade pharmacists with 3-4 months training. The average age of the participants was 29.6 ± 1.2 years. The average length of service for the community pharmacists was 7.6 ± 1.3 years. The top issues that patients consulted with the pharmacists were on medication use (76%), which physician they should visit (54%) and therapy (26%). There was not a significant effect of work experience of community pharmacists on their attitudes toward community-based clinical services. In this study, we observed that 95% community pharmacies provide blood pressure measurement facility, 90% provide diabetes screening, 76% provide dressing services, and only 47% provide nebulization. No community pharmacist was found to be involved with adverse drug reaction reporting. In conclusion, we recommend that the government and the pharmacy regulatory authority should take sufficient initiatives to develop the community pharmacy sector in Bangladesh for the welfare of mankind.Bangladesh Pharmaceutical Journal 18(2): 137-141, 2015
Antitumor, Analgesic and Anti-inflammatory Activities of Glochidion multiloculare (Rottler ex Willd) Voigt
Authors: Kabir Selina , Zahan Ronok , Chowdhury Abdullah Mohammad Sarwaruddin , Haque Mohammad Rashedul , Rashid Mohammad Abdur
Published: July 2015

The antitumor, analgesic and anti-inflammatory activities of the methanol extract (MEGM) of Glochidion multiloculare and its petroleum ether (PEFGM), carbon tetrachloride (CTFGM) and chloroform (CHFGM) soluble fractions were investigated. The antitumor activity of the extract/fractions was determined against Ehrlichs ascites carcinoma (EAC) in mice at 20 mg/kg body weight intraperitoneally. Increase of survival time by 24 ± 0.12, 26 ± 0.40, 21 ± 0.12 and 27 ± 0.42 days was observed by the MEGM, PEFGM, CTFGM and CHFGM treated tumor bearing mice compared to the control group (20 ± 0.12 days). Hematological studies revealed that heamoglobin (Hb) content was decreased in EAC treated mice whereas restoration to normal levels was observed in extract/fractions treated animals. Significant decrease in RBC and increase in WBC counts were observed in extract/fractions treated animals when compared to EAC affected animals. Both extract and fractions at the dose of 100 mg/kg b.w. significantly increased the pain threshold in tail immersion method and reduced the writhing caused by acetic acid induced method. The MEGM, PEFGM, CTFGM and CHFGM showed anti-inflammatory activities at 100 mg/kg b.w. This is the first report of antitumor, analgesic and anti-inflammatory potential of G. multiloculare.Bangladesh Pharmaceutical Journal 18(2): 142-148, 2015
Screening and Characterization of Bacteriocin-Like Inhibitory Substances Produced by Bangladeshi Strains of Bacillus thuringiensis
Authors: Islam Md Nahidul , Akhand Nahinur Rahman , Mamun Arafat Al , Shishir Asaduzzaman , Aktar Marufa Zerin , Khan Shakila Nargis , Hoq Md Mozammel , Hossain Mohammad Shahnoor
Published: July 2015

Bacteriocins are ribosomally synthesized antibacterial peptides which have the potential to be used as natural food preservatives as well as alternative to antibiotics. Here, we report the production of bacteriocin-like inhibitory substances (BLIS) from the indigenous strains of Bacillus thuringiensis. Deferred antagonism bacteriocin assay and agar well diffusion methods suggested that several of the tested strains have high levels of bacteriocin-like activity against the common food-borne pathogens, Listeria monocytogenes, Staphylococcus aureus and Bacillus cereus. These bacteriocins are generally produced at the mid-logarithmic phase of growth with optimum temperature of 37 ºC, pH-7.0 and 24 h of incubation. Heat stability assay demonstrated that the bacteriocins produced from the strains are highly heat stable and can retain activity up to 100 ºC. Our study suggests that these bacteriocins may be potential candidates for use as biodegradable natural food preservatives and alternative antimicrobial agents to solve the increasing trends of problems of antibiotic resistance.Bangladesh Pharmaceutical Journal 18(2): 149-156, 2015
Formulation and in vitro Evaluation of Glimepiride Sustained Release Tablets: Comparison with Immediate Release Tablets
Authors: Karim Samira , Bhuiyan Mohiuddin Ahmed , Rana Md Sohel
Published: July 2015

This work aims at the design of a sustained release formulation of glimepiride which is currently available in the treatment of type 2 diabetes mellitus and to investigate the effect of polymers on the release profile of glimepiride. Glimepiride sustained release tablets were prepared by direct compression method using different ratios of various release retarding polymers such as carbopol, ethyl cellulose, methocel K4 MCR, methocel K15 MCR, methocel K100 MCR and xanthum gum. These formulations were also compared with glimepiride immediate release tablets. The prepared tablets were subjected to various physical parameter tests including weight variation, friability, hardness, thickness, diameter, etc. In vitro dissolution studies of the formulations were done at pH 6.8 in phosphate buffer using USP apparatus 2 (paddle method) at 50 rpm. The percent releases of all the formulations (30) were 73.11%- 98.76% after 8 hours. The release pattern followed zero order kinetics and the release of the drug was hindered by the polymers used in the study. On the other hand, 100% drug was released within 1 hour from the immediate release tablet of glimepiride. The study reveals that the polymers used have the capacity to retard the release of the drug from the sustained release tablets and the more is the amount of the polymer in the formulation the less is the release of drug showing more retardation of drug release.Bangladesh Pharmaceutical Journal 18(2): 157-162, 2015
Development and Validation of a UV-Spectrophotometric Method for Determination of Vildagliptin and Linagliptin in Bulk and Pharmaceutical Dosage Forms
Authors: Banik Sujan , Karmakar Palash , Miah Md Anowar Hossain
Published: July 2015

The present study was undertaken to develop a spectrophotometric method for determination of vildagliptin and Linagliptin in pharmaceutical dosage forms. This paper describes a simple, rapid, accurate and precise UVspectrophotometric method for the assay of vildagliptin and linagliptin in bulk and marketed tablet dosage forms. The validation of the developed method was carried out according to ICH guidelines with respect to linearity, precision, accuracy, specificity, limit of detection and limit of quantification. Calibration curves were obtained in the concentration range of 8-32 ?g/ml for vildagliptin and 5-25 ?g/ml for linagliptin with good correlation coefficients (r=0.999). The precisions of the new method for both drugs were less than the maximum allowable limit (%RSD < 2.0) specified by the USP, ICH and FDA. Therefore, the method was found to be an accurate, reproducible and sensitive for analysis of vildagliptin and linagliptin in pharmaceutical dosage forms.Bangladesh Pharmaceutical Journal 18(2): 163-168, 2015
Anti-inflammatory and Antioxidant Activities of Cucumis sativus Leaves
Authors: Nasrin Fatema , Bulbul Israt Jahan , Aktar Fahima , Rashid Mohammad A
Published: July 2015

This study was carried out to evaluate the anti-inflammatory and antioxidant activities of Cucumis sativus Linn. (Family: Cucurbitaceae) leaves. The methanolic extract of C. sativus leaves (MCS) was investigated for antiinflammatory activities in Long Evans rat model at two different doses of 150 and 250 mg/kg body weight and the effects were compared with the standard, indomethacin (10 mg/kg body weight). It exhibited highest antiinflammatory activity at the dose 250 mg/kg. In the formalin test, the extract at both doses (150 and 250 mg/kg body weight) significantly prevented the increase in volume of paw edema (P<0.05 and P<0.001). In carrageenan-induced paw edema test the MCS significantly (P?0.001) reduced inflammation by 57.35 % (150 mg/kg body weight) and 72.06% (250 mg/kg body weight) in comparison to the standard drug, indomethacin (79.41%) at the end of 5h. MCS was also screened for DPPH scavenging activity, total antioxidant capacity, reducing ability as well as total phenolics content to assess its antioxidant potential. Total phenolic content and total antioxidant capacity of MCS were found to be 262.31 mg/g equivalent of gallic acid and 267.2 mg/g equivalent of ascorbic acid, respectively. The IC50 of free radical scavenging of DPPH was 13.06 ?g/ml while that of standard ascorbic acid was 13.17 ?g/ml. The reducing power of MCS was found to be concentration dependent.Bangladesh Pharmaceutical Journal 18(2): 169-173, 2015
Survey on Antibiotic Practices in Chittagong City of Bangladesh
Authors: Sayeed Mohammed Abu , Iqbal Nurunnobi , Ali Md Sekendar , Rahman Md Masudur , Islam Md Rafikul , Jakaria Md
Published: July 2015

We aimed to determine the amount of antibiotic prescribed by physicians and also sold by pharmacies in Chittagong city of Bangladesh by using a cross sectional survey. Patients, physicians, pharmacies and prescriptions based study was conducted in May 01, 2012 to May 30, 2012. A total of 118 prescriptions were collected and 82 local pharmacies were selected for data collection about daily sales of antibiotics. It was evident that 69.49% of the prescriptions contained antibiotics. Azithromycin and cefixim were found to be the most preferred antibiotics in physicians prescriptions survey. On the other hand, it was evident from the pharmacy survey (without prescription) selling rates of azithromycin and ciprofloxacin were more predominant. The diseases which were seen in the studies include cough, typhoid, diarrhea, nausea, chronic UTI, RTI, fever and rhinitis. The result of the present survey indicates that antibiotics are widely and inappropriately practiced without following standard guidelines. This is an alarming condition in the health sector of Bangladesh and therefore, the respective authority should take necessary steps to minimize the harmful effects of antibiotics.Bangladesh Pharmaceutical Journal 18(2): 174-178, 2015
Bioaccumulation and Toxicity of Iron Salt on Shingi Fish Heteropneustes fossils (Bloch) and its Possible Impacts on Human Health
Authors: Jahan Iftear , Siddiki AKM Nur Alam , Naser M Niamul , Salam Md Abdus
Published: July 2015

The freshwater Stinging catfish locally known as Shingi (Heteropneustes fossilis) is exposed to various concentrations of analytical grade FeSO4.7H2O. The LC50 values for Fe2+ were found to be 109, 68 and 45 mg/l at 24, 48 and 72 hrs, respectively indicating that the toxicity increased with time. Gills appear to be the first target organ for iron toxicity followed by the liver and muscle. Moisture contents in fish tissue increased due to release of the toxicant by biological way. Protein and lipid contents are decreased and ash content is increased with the increase of exposure time. In contrast, iron is relatively nontoxic to Shingi fish at low dose, but long time exposure has adverse effects in fish tissue. Thus, exposure to iron salt at toxic level resulted in accumulation of iron in fish tissue. Hence, the consumption of this type of contaminated fish might have detremental effect on human health. However, this needs extensive study to make any final conclusion.Bangladesh Pharmaceutical Journal 18(2): 179-182, 2015
Active Fractions from Asparagus racemosus Willd. with Thrombolytic, Membrane Stabilizing and Free Radical Scavenging Activities
Authors: Jalil Md Abdul , Rahman Mohammad Sharifur , Rahman SM Ashikur , Rashid Ridwan B , Rashid Mohammad A
Published: July 2015

Abstract not availableBangladesh Pharmaceutical Journal 18(2): 183-186, 2015
Recent Pharma News 18(2)
Authors: Hossain Md Akbar
Published: July 2015

Abstract not availableBangladesh Pharmaceutical Journal 18(2): 187-191, 2015
New drugs approval 18(2)
Authors: Hossain Md Akbar
Published: July 2015

Abstract not availableBangladesh Pharmaceutical Journal 18(2): 192-194, 2015
Dynamical Analysis of a Stage-Structured Model for Lyme Disease with Two Delays
Authors: Li Dan , Ma Wanbiao
Published: July 2015

In this paper, a nonlinear stage-structured model for Lyme disease is considered. The model is a system of diòerential equations with two time delays. We derive the basic reproductive rate R0(τ1, τ2). If (τ1, τ2) < 1, then the boundary equilibriumis globally asymptotically stable. If R0(τ1, τ2) > 1, then there exists a unique positive equilibrium whose local asymptotic stability and the existence of Hopf bifurcations are established by analyzing the distribution of the characteristic values. An explicit algorithm for determining the direction of Hopf bifurcations and the stability of the bifurcating periodic solutions is derived by using the normal form and the center manifold theory. Some numerical simulations are performed to confirm the correctness of theoretical analysis. Finally, some conclusions are given.
Positive Solutions for the Generalized Nonlinear Logistic Equations
Authors: Gasiński Leszek , Papageorgiou Nikolaos S.
Published: July 2015

We consider a nonlinear parametric elliptic equation driven by a nonhomogeneous differential operator with a logistic reaction of the superdiòusive type. Using variationalmethods coupled with suitable truncation and comparison techniques, we prove a bifurcation type result describing the set of positive solutions as the parameter varies.
The Effect of Practices of Management by Wandering on Learning Organization "A Study on World Islamic Sciences and Education University”
Authors: AL-Qeed Marzouq Ayed
Published: July 2015

The study aimed to identify Management by wandering and their relationship to the learning organization, and from this main point, the study aimed to explain the meaning and nature of the management by wandering and study the relationship between management and performance of the employee and their relationship with the characteristics of the learning organization and to focus on the role of management by wandering in the motivation and positive interaction for the employee in educational organizations. The study used descriptive analytical methodology, because it enables us to study the phenomenon as it exists in fact, described and describe it in order to understand the relationships between phenomena’s.

The most important results of the study are: 1)The most important recommendation is need to encourage departments at the University of Islamic Sciences to practice all the dimensions of Management by wandering in the biggest manner, and dissemination Management by wandering as a culture aimed to activate the trend toward building a learning organization, and to achieve positive communication between departments and subordinates, and to encourage teamwork in problem solving. 2) Focus on the achievement of development and innovation through knowledge generated from the administration's practice of Management by wandering and encouraging employees to find innovative ways to develop educational services and develop a new management and Academy methods of, and that for importance in building a learning organization.
The Effect of Human Resources Practices on Organizational Commitment: A Jordanian Study
Authors: Suifan Taghrid Saleh
Published: July 2015

Abstract

The effect of human resources practices on organizational commitment was examined in this study using a sample of 500 subjects randomly selected from employees working for public and private organization in various industries in Amman, the capital city of Jordan. Of the mailed questionnaires, 431 questionnaires were returned with a response rate of 86 percent. A bulk of scales was adopted from related works to measure constructs. Organizational commitment was measured by organizational commitment scale developed by Meyer and Allen (1997), training was measured using a scale developed by Yahya and Goh (2002), person-organization fit was measured by a scale developed by Netemeyer et al. (1997), and, finally, rewards construct was measured by a scale adopted from Sejjaaka and Kaawaase (2014). The results pointed out that all HR practices examined (training, person-organization fit, and rewards) were significantly and positively associated with organizational commitment. Research limitations and future research directions were brought out.   
Buyer Supplier Relationship Analysis (A Case Study of C.V. CS)
Authors: Kurnia Haryanto Wiguna , Wahjudono Denny Bernardus Kurnia
Published: July 2015

The purpose of this research is to discover the factors that shape the relationship between C.V. CS as buyer and the suppliers in order to determine the most appropriate strategy to manage the relationship. This research uses quantitative method and exploratory factor analysis approach. The population of this research consists of 30 suppliers of C.V. CS. Saturated sampling is used as sampling technique in this study. Additionally, the entire population is used as respondents. Research results suggest a new factor which can be considered as a simplified version of the six research variables of communication, trust, capacity and capability, relationship continuity, dependence and commitment. This factor is called strategic partnership. Strategic partnership is considered as the most suitable strategy for C.V. CS to establish a relationship with their suppliers. The findings of this research also indicate that strategic partnership can act as relationship builder between buyers and suppliers. In order to create a perfect strategic partnership, the five forming elements must be fulfilled.
Radar signatures of snowflake riming: A modeling study
Authors: Leinonen Jussi , Szyrmer Wanda
Published: July 2015

The capability to detect the state of snowflake riming reliably from remote measurements would greatly expand the understanding of its global role in cloud‐precipitation processes. To investigate the ability of multifrequency radars to detect riming, a three‐dimensional model of snowflake growth was used to generate simulated aggregate and crystal snowflakes with various degrees of riming. Three different growth scenarios, representing different temporal relationships between aggregation and riming, were formulated. The discrete dipole approximation was then used to compute the radar backscattering properties of the snowflakes at frequencies of 9.7, 13.6, 35.6, and 94 GHz. In two of the three growth scenarios, the rimed snowflakes exhibit large differences between the backscattering cross sections of the detailed three‐dimensional models and the equivalent homogeneous spheroidal models, similarly to earlier results for unrimed snowflakes. When three frequencies are used simultaneously, riming appears to be detectable in a robust manner across all three scenarios. In spite of the differences in backscattering cross sections, the triple‐frequency signatures of heavily rimed particles resemble those of the homogeneous spheroids, thus explaining earlier observational results that were compatible with such spheroids.
Rising methane emissions from northern wetlands associated with sea ice decline
Authors: Parmentier Frans‐Jan W. , Zhang Wenxin , Mi Yanjiao , Zhu Xudong , van Huissteden Jacobus , Hayes Daniel J. , Zhuang Qianlai , Christensen Torben R. , McGuire A. David
Published: July 2015

The Arctic is rapidly transitioning toward a seasonal sea ice‐free state, perhaps one of the most apparent examples of climate change in the world. This dramatic change has numerous consequences, including a large increase in air temperatures, which in turn may affect terrestrial methane emissions. Nonetheless, terrestrial and marine environments are seldom jointly analyzed. By comparing satellite observations of Arctic sea ice concentrations to methane emissions simulated by three process‐based biogeochemical models, this study shows that rising wetland methane emissions are associated with sea ice retreat. Our analyses indicate that simulated high‐latitude emissions for 2005–2010 were, on average, 1.7 Tg CH4 yr−1 higher compared to 1981–1990 due to a sea ice‐induced, autumn‐focused, warming. Since these results suggest a continued rise in methane emissions with future sea ice decline, observation programs need to include measurements during the autumn to further investigate the impact of this spatial connection on terrestrial methane emissions.
Probability density functions for the variable solar wind near the solar cycle minimum
Authors: Vörös Z. , Leitner M. , Narita Y. , Consolini G. , Kovács P. , Tóth A. , Lichtenberger J.
Published: July 2015

Unconditional and conditional statistics are used for studying the histograms of magnetic field multiscale fluctuations in the solar wind near the solar cycle minimum in 2008. The unconditional statistics involves the magnetic data during the whole year in 2008. The conditional statistics involves the magnetic field time series split into concatenated subsets of data according to a threshold in dynamic pressure. The threshold separates fast‐stream leading edge compressional and trailing edge uncompressional fluctuations. The histograms obtained from these data sets are associated with both multiscale (B) and small‐scale (δB) magnetic fluctuations, the latter corresponding to time‐delayed differences. It is shown here that, by keeping flexibility but avoiding the unnecessary redundancy in modeling, the histograms can be effectively described by a limited set of theoretical probability distribution functions (PDFs), such as the normal, lognormal, kappa, and log‐kappa functions. In a statistical sense the model PDFs correspond to additive and multiplicative processes exhibiting correlations. It is demonstrated here that the skewed small‐scale histograms inherent in turbulent cascades are better described by the skewed log‐kappa than by the symmetric kappa model. Nevertheless, the observed skewness is rather small, resulting in potential difficulties of estimation of the third‐order moments. This paper also investigates the dependence of the statistical convergence of PDF model parameters, goodness of fit, and skewness on the data sample size. It is shown that the minimum lengths of data intervals required for the robust estimation of parameters is scale, process, and model dependent.
The effect of changing solar wind conditions on the inner magnetosphere and ring current: A model data comparison
Authors: Patra S. , Spencer E.
Published: July 2015

We investigate the rate at which the open drift paths in the near‐Earth magnetosphere convert to closed paths during events with a sudden northward turning of the interplanetary magnetic field (IMF Bz) after the peak of a geomagnetic storm. The geomagnetic storm on 17 August 2001 with an abrupt turning of the IMF Bz after the peak in SYM‐H index is chosen in this study. The Block‐Adaptive‐Tree Solar‐Wind Roe‐Type Upwind Scheme model along with the Fok Ring Current (FRC) model available at Community Coordinated Modeling Center is used to model this event. The unique movie maps of the worldwide magnetometer stations are used to compare with the numerical results. The results indicate that ground magnetic disturbance remains asymmetric for some time after the start of the recovery phase even for a storm with abrupt northward turning of the IMF Bz. FRC simulation results suggest that the flow‐out losses decrease under weakened magnetospheric convection but at a rate slower than the change in IMF Bz. These results indicate that the flow‐out losses rapidly become smaller as the IMF Bz turns northward during the early recovery phase of a storm and the contribution of the tail current to the SYM‐H index is important.
Formation of polar ionospheric tongue of ionization during minor geomagnetic disturbed conditions
Authors: Liu Jing , Nakamura Takuji , Liu Libo , Wang Wenbin , Balan Nanan , Nishiyama Takanori , Hairston Marc R. , Thomas E. G.
Published: July 2015

Previous investigations of ionospheric storm‐enhanced density (SED) and tongue of ionization (TOI) focused mostly on the behavior of TOI during intense geomagnetic storms. Little attention has been paid to the spatial and temporal variations of TOI during weak to moderate geomagnetic disturbed conditions. In this paper we investigate the source and development of TOI during a moderate geomagnetic storm on 14 October 2012. Multi‐instrumental observations including GPS total electron content (TEC), Defense Meteorological Satellite Program (DMSP) in situ measured total ion concentration and ion drift velocity, SuperDARN measured polar ion convection patterns, and electron density profiles from the Poker Flat Incoherent Scatter Radar (PFISR) have been utilized in the current analysis. GPS TEC maps show salient TOI structures persisting for about 5 h over high latitudes of North America on 14 October 2012 in the later recovery phase of the storm when the magnitudes of IMF By and Bz were less than 5 nT. The PFISR electron density profiles indicate that the extra ionization for TEC enhancements mainly occurred in the topside ionosphere with no obvious changes in the bottomside ionosphere and vertical plasma drifts. Additionally, there were no signatures of penetration electric fields in the equatorial electrojet data and upward ion drifts at high latitudes. At the same time, strong subauroral polarization streams with ion drift speeds exceeding 2.5 km/s carried sunward fluxes and migrated toward lower latitudes for about 5° based on the DMSP cross‐track drift measurements. Based on those measurements, we postulate that the combined effects of initial build‐up of ionization at midlatitudes through daytime production of ionization and equatorward (or less poleward than normal daytime) neutral wind reducing downward diffusion along the inclined filed lines, and an expanded polar ion convection pattern and its associated horizontal plasma transport are important in the formation of the TOI.
Fringe field dynamics over equatorial and low‐latitude ionosphere: A three‐dimensional perspective
Authors: Kherani E. A. , Patra A. K.
Published: July 2015

This paper presents a three‐dimensional simulation of the collisional interchange instability generating equatorial plasma bubble (EPB) in the evening ionospheric F region and associated fringe field (FF) in the valley‐upper‐E (VE) region. This simulation is primarily intended to address hitherto unexplained radar observations of ascending irregularity structures only in the vicinity of the magnetic equator in association with the EPB phenomenon. Novel results of the present simulation are the following: (1) EPB‐associated FF penetrating into the E region is found to be confined to a latitude belt of ±5∘, (2) ascending irregularity structures from the E region is formed only when perturbation in plasma parameters similar to those responsible for forming EPB are present in the VE region, and (3) perturbation in the VE region provide conditions for the formation of ascending irregularity structures on the eastern wall of the plasma bubble. These results are in excellent agreement with radar observations and also account for the presence of metallic ions in the EPB at and above the F region peak.
The impacts of mantle phase transitions and the iron spin crossover in ferropericlase on convective mixing—is the evidence for compositional convection definitive? New results from a Yin‐Yang overset grid‐based control volume model
Authors: Shahnas M. H. , Peltier W. R.
Published: July 2015

High‐resolution seismic tomographic images from several subduction zones provide evidence for the inhibition of the downwelling of subducting slabs at the level of the 660 km depth seismic discontinuity. Furthermore, the inference of old (~140 Myr) sinking slabs below fossil subduction zones in the lower mantle has yet to be explained. We employ a control volume methodology to develop a new anelastically compressible model of three‐dimensional thermal convection in the “mantle” of a terrestrial planet that fully incorporates the influence of large variations in material properties. The model also incorporates the influence of (1) multiple solid‐solid pressure‐induced phase transitions, (2) transformational superplasticity at 660 km depth, and (3) the high spin‐low spin iron spin transition in ferropericlase at midmantle pressures. The message passing interface‐parallelized code is successfully tested against previously published benchmark results. The high‐resolution control volume models exhibit the same degree of radial layering as previously shown to be characteristic of otherwise identical 2‐D axisymmetric spherical models. The layering is enhanced by the presence of moderate transformational superplasticity, and in the presence of the spin crossover in ferropericlase, stagnation of cold downwellings occurs in the range of spin crossover depths (~1700 km). Although this electronic spin transition has been suggested to be invisible seismically, recent high‐pressure ab initio calculations suggest it to have a clear signature in body wave velocities which could provide an isochemical explanation of a seismological signature involving the onset of decorrelation between Vp and Vs that has come to be interpreted as requiring compositional layering.
Aerosol transport over the Andes from the Amazon Basin to the remote Pacific Ocean: A multiyear CALIOP assessment
Authors: Bourgeois Quentin , Ekman Annica M. L. , Krejci Radovan
Published: July 2015

Six years (2007–2012) of data from the Cloud‐Aerosol Lidar with Orthogonal Polarization (CALIOP) satellite instrument were used to investigate the vertical distribution and transport of aerosols over the tropical South American continent and the southeast Pacific Ocean. The multiyear aerosol extinction assessment indicates that aerosols, mainly biomass burning particles emitted during the dry season in the Amazon Basin, are lifted in significant amounts over the Andes. The aerosols are mainly transported in the planetary boundary layer between the surface and 2 km altitude with an aerosol extinction maximum near the surface. During the transport toward the Andes, the aerosol extinction decreases at a rate of 0.02 km−1 per kilometer of altitude likely due to dilution and deposition processes. Aerosols reaching the top of the Andes, at altitudes typically between 4 and 5 km, are entrained into the free troposphere (FT) over the southeast Pacific Ocean. A comparison between CALIOP observations and ERA‐Interim reanalysis data indicates that during their long‐range transport over the tropical Pacific Ocean, these aerosols are slowly transported toward the marine boundary layer by the large‐scale subsidence at a rate of 0.4 cm s−1. The observed vertical/horizontal transport ratio is 0.7–0.8 m km−1. Continental aerosols linked to transport over the Andes can be traced on average over 4000 km away from the continent indicating an aerosol residence time of 8–9 days in the FT over the Pacific Ocean. The FT aerosol optical depth (AOD) above the Pacific Ocean near South American coast accounts on average for 6% and 25% of the total AOD during the season of low and high biomass burning, respectively. This result shows that, during the biomass burning season, continental aerosols largely influence the AOD over the remote southeast Pacific Ocean. Overall, FT AOD decrease exponentially with the distance to continental sources at a rate of about 10% per degree of longitude over the Pacific Ocean.
Assessing and improving Noah‐MP land model simulations for the central Tibetan Plateau
Authors: Gao Yanhong , Li Kai , Chen Fei , Jiang Yingsha , Lu Chungu
Published: July 2015

The Tibetan Plateau (TP) region experiences strong land‐atmosphere interactions, and as an elevated heating source, significantly influences the formation of the Asian monsoon. Those interactions are not well represented in current land‐surface models (LSMs), partly due to difficulties in representing heterogeneities in soil structures in LSM. Simulations using the Noah with multiparameterization options (Noah‐MP) LSM are employed to assess the relative importance of parameterizing vertical soil heterogeneity, organic matter, and soil rhizosphere and their impacts on seasonal evolution of soil temperature, soil moisture, and surface energy and water budgets at the sparsely vegetated Amdo site located in central TP. The LSM spin‐up time at the central TP depends on the complexity of the model physics, ranging from 4 years with simplest soil physics to 30 years with the addition of organic matter and spare to dense rhizosphere parameterization in Noah‐MP. Representing layered soil texture and organic matter does not improve low biases in topsoil moisture. Reducing the saturated conductivity from the mucilage in the rhizosphere produces better results. Surface sensible and latent heat fluxes are better simulated in the monsoon season as well. Adding layered soil texture and organic matter in Noah‐MP retard the thawing in deep soil layers, and the rhizosphere effect delays thawing even more in the transient season. Uncertainties in soil initialization significantly affect deep‐soil temperature and moisture, but uncertainties in atmospheric forcing conditions mainly affect topsoil variables and consequently the surface energy fluxes. Differing land‐surface physics cause 36% uncertainty in the accumulated evapotranspiration and subsurface runoff.
Retrieving the height of smoke and dust aerosols by synergistic use of VIIRS, OMPS, and CALIOP observations
Authors: Lee Jaehwa , Hsu N. Christina , Bettenhausen Corey , Sayer Andrew M. , Seftor Colin J. , Jeong Myeong‐Jae
Published: July 2015

This study extends the application of the previously developed Aerosol Single‐scattering albedo and layer Height Estimation (ASHE) algorithm, which was originally applied to smoke aerosols only, to both smoke and dust aerosols by including nonspherical dust properties in the retrieval process. The main purpose of the algorithm is to derive aerosol height information over wide areas using aerosol products from multiple satellite sensors simultaneously: aerosol optical depth (AOD) and Ångström exponent from the Visible Infrared Imaging Radiometer Suite (VIIRS), UV aerosol index from the Ozone Mapping and Profiler Suite (OMPS), and total backscatter coefficient profile from the Cloud‐Aerosol Lidar with Orthogonal Polarization (CALIOP). The case studies suggest that the ASHE algorithm performs well for both smoke and dust aerosols, showing root‐mean‐square error of the retrieved aerosol height as compared to CALIOP observations from 0.58 to 1.31 km and mean bias from −0.70 to 1.13 km. In addition, the algorithm shows the ability to retrieve single‐scattering albedo to within 0.03 of Aerosol Robotic Network inversion data for moderate to thick aerosol loadings (AOD of ~1.0). For typical single‐layered aerosol cases, the estimated uncertainty in the retrieved height ranges from 1.20 to 1.80 km over land and from 1.15 to 1.58 km over ocean when favorable conditions are met. Larger errors are observed for multilayered aerosol events, due to the limited sensitivities of the passive sensors to such cases.
Knee Osteoarthritis Worsening Across the Disease Spectrum and Future Knee Pain, Symptoms, and Functioning: A Multisite Prospective Cohort Study
Authors: Riddle Daniel L. , Makowski Mateusz , Kong Xiangrong
Published: July 2015

Objective

Prognostic estimates for knee osteoarthritis worsening over the full disease spectrum have not been reported. Osteoarthritis Initiative data were used to determine the association between knee radiographic osteoarthritis worsening and future knee pain and function.

Methods

Yearly data over a 5‐year period were analyzed. Outcome measures were the Western Ontario and McMaster Universities Osteoarthritis Index and the Knee Injury and Osteoarthritis Outcome Score pain and symptoms scales. Knees were grouped based on whether yearly Kellgren/Lawrence (K/L) grades worsened. Associations of yearly K/L worsening with knee pain, symptoms, or function scores at the end of the year and with lagged outcomes observed at least 1 year after worsening were assessed using linear models with generalized estimating equations.

Results

A total of 25,932 knee‐years of observations were examined in the primary analysis. For knees with yearly K/L worsening, all outcome scores were significantly worse (P values from 0.02 to <0.001) at the end of the index year, as compared to unchanged knees. All outcomes for knees with worsened versus unchanged K/L scores exceeded the minimal clinically important difference (MCID). For lagged effects, outcomes at 1 year following the index K/L year exceeded the MCID and were statistically significant (P ≤ 0.001) for knees with baseline K/L grades of 2 or 3.

Conclusion

K/L worsening over a 1‐year period is prognostically important over the short term for all baseline K/L grades, and for knees with baseline K/L grades of 2 or 3 worsening continues over the following year.
Physical Activity Patterns Among Older Adults With and Without Knee Osteoarthritis in Six European Countries
Authors: Herbolsheimer Florian , Schaap Laura A. , Edwards Mark H. , Maggi Stefania , Otero Ángel , Timmermans Erik J. , Denkinger Michael D. , van der Pas Suzan , Dekker Joost , Cooper Cyrus , Dennison Elaine M. , van Schoor Natasja M. , Peter Richard ,   the Eposa Study Group
Published: July 2015

Objective

To investigate patterns of physical activity in older adults with knee osteoarthritis (OA) compared to older adults without knee OA across 6 European countries. We expect country‐specific differences in the physical activity levels between persons with knee OA compared to persons without knee OA. A varying degree of physical activity levels across countries would express a facilitating or impeding influence of the social, environmental, and other contextual factors on a physically active lifestyle.

Methods

Baseline cross‐sectional data from the European Project on Osteoarthritis were analyzed. In total, 2,551 participants from 6 European countries (Germany, Italy, The Netherlands, Spain, Sweden, and the UK) were included.

Results

Participants with knee OA were less likely to follow physical activity recommendations and had poorer overall physical activity profiles than those without knee OA (mean 62.9 versus 81.5 minutes/day, respectively; P = 0.015). The magnitude of this difference varied across countries. Detailed analysis showed that low physical activity levels in persons with knee OA could be attributed to less everyday walking time (odds ratio 1.31, 95% confidence interval 1.07–1.62).

Conclusion

This study highlighted the fact that having knee OA is associated with a varying degree of physical activity patterns in different countries. This national variation implies that low levels of physical activity among persons with knee OA cannot be explained exclusively by individual or disease‐specific factors, but that social, environmental, and other contextual factors should also be taken into account.
Risk of Pulmonary Embolism and Deep Venous Thrombosis in Systemic Sclerosis: A General Population‐Based Study
Authors: Schoenfeld Sara R. , Choi Hyon K. , Sayre Eric C. , Aviña‐Zubieta J. Antonio
Published: July 2015

Objective

To determine the risk of venous thromboembolism (VTE) (pulmonary embolism [PE] and deep vein thrombosis [DVT]) in individuals with incident systemic sclerosis (SSc; scleroderma) in the general population.

Methods

Using a population database that includes all residents of British Columbia, Canada, we conducted a cohort study of all patients with incident SSc and up to 10 age‐, sex‐, and entry time–matched individuals from the general population. We compared incidence rates of PE, DVT, and VTE between the 2 groups according to SSc disease duration. We calculated hazard ratios (HRs), adjusting for confounders.

Results

Among 1,245 individuals with SSc (83% female, mean age 56 years), the incidence rates of PE, DVT, and VTE were 3.47, 3.48, and 6.56 per 1,000 person‐years, respectively, whereas the corresponding rates were 0.78, 0.76, and 1.37 per 1,000 person‐years among 12,670 non‐SSc individuals. Compared with non‐SSc individuals, the multivariable HRs among SSc patients were 3.73 (95% confidence interval [95% CI] 1.98–7.04), 2.96 (95% CI 1.54–5.69), and 3.47 (95% CI 2.14–5.64) for PE, DVT, and VTE, respectively. The age‐, sex‐, and entry time–matched HRs for PE, DVT, and VTE were highest during the first year after SSc diagnosis (32.77 [95% CI 6.60–162.75], 8.50 [95% CI 3.13–23.04], and 12.03 [95% CI 5.27–27.45], respectively).

Conclusion

These findings provide population‐based evidence that SSc patients are at a substantially increased risk of VTE, especially within the first year after SSc diagnosis. Increased monitoring for this potentially fatal outcome and its modifiable risk factors is warranted in this patient population.
Synthesis and Olfactory Properties of 2‐Substituted and 2,3‐Annulated 1,4‐Dioxepan‐6‐ones
Authors: Plummer Christopher M. , Kraft Philip , Froese Jordan , Hudlický Tomáš , Rook Trevor J. , Jones Oliver A. H. , Hügel Helmut M.
Published: July 2015

The synthesis and olfactory properties of a series of 2‐substituted and 2,3‐annulated 1,4‐dioxepan‐6‐ones is reported. By Williamson etherification with 3‐chloro‐2‐(chloromethyl)prop‐1‐ene (6) and subsequent Katsuki–Sharpless oxidation, 1,4‐dioxepan‐6‐one (8 a) and its 2‐methyl (8 b), 2‐propyl (8 c), 2‐isobutyl (8 d), and 2,2,3,3‐tetramethyl derivative (8 e), as well as four 2,3‐annulated 1,4‐dioxepan‐6‐ones 8 h, 8 i, 8 j, and 8 k were synthesised. By etherification with ethyl diazoacetate and subsequent Dieckmann cyclisation, (5aS,9aS)‐9‐bromo‐ and 9‐iodo‐5a,6,7,9a‐tetrahydro‐2 H‐benzo[b][1,4]dioxepin‐3(4 H)‐one (8 f/g) as well as a 2,3‐annulated derivative 8 m from (+)‐limonene were prepared. 2‐Propyl‐1,4‐dioxepan‐6‐one (8 c) was discovered to have a green floral odour with anisic and cinnamic nuances, which could be rationalised by a superposition analysis. The olfactory properties of the 1,4‐dioxepan‐6‐ones synthesised underline the crucial importance of a benzenoid ring system for marine odorants.
Protein‐induzierte Farbverschiebung von Carotenoiden in β‐Crustacyanin
Authors: Gamiz‐Hernandez Ana P. , Angelova Iva Neycheva , Send Robert , Sundholm Dage , Kaila Ville R. I.
Published: July 2015

Das Pigment β‐Crustacyanin (β‐CR) verursacht die Farbe des blauen Hummers. Wir zeigen mithilfe korrelierter Ab‐initio‐Rechnungen, wie die Proteinumgebung die Farbe der β‐CR‐Farbstoffe mittels elektrostatischer und sterischer Effekte bestimmt.