bluuebunny/crossref_metadata_2025 huggingface dataset:
Structural and functional studies of the Thermus thermophilus 16S rRNA methyltransferase RsmG
Authors: Gregory Steven T. , Demirci Hasan , Belardinelli Riccardo , Monshupanee Tanakarn , Gualerzi Claudio , Dahlberg Albert E. , Jogl Gerwald
Published: July 2009

The RsmG methyltransferase is responsible for N7 methylation of G527 of 16S rRNA in bacteria. Here, we report the identification of the Thermus thermophilus rsmG gene, the isolation of rsmG mutants, and the solution of RsmG X-ray crystal structures at up to 1.5 Å resolution. Like their counterparts in other species, T. thermophilus rsmG mutants are weakly resistant to the aminoglycoside antibiotic streptomycin. Growth competition experiments indicate a physiological cost to loss of RsmG activity, consistent with the conservation of the modification site in the decoding region of the ribosome. In contrast to Escherichia coli RsmG, which has been reported to recognize only intact 30S subunits, T. thermophilus RsmG shows no in vitro methylation activity against native 30S subunits, only low activity with 30S subunits at low magnesium concentration, and maximum activity with deproteinized 16S rRNA. Cofactor-bound crystal structures of RsmG reveal a positively charged surface area remote from the active site that binds an adenosine monophosphate molecule. We conclude that an early assembly intermediate is the most likely candidate for the biological substrate of RsmG.
The Sound of Silence: Observational Learning in the U.S. Kidney Market
Authors: Zhang Juanjuan
Published: July 2009

Mere observation of others' choices can be informative about product quality. This paper develops an individual-level dynamic model of observational learning and applies it to a novel data set from the U.S. kidney market, where transplant candidates on a waiting list sequentially decide whether to accept a kidney offer. We find strong evidence of observational learning: patients draw negative quality inferences from earlier refusals in the queue, thus becoming more inclined towards refusal themselves. This self-reinforcing chain of inferences leads to poor kidney utilization despite the continual shortage in kidney supply. Counterfactual policy simulations show that patients would have made more efficient use of kidneys had the concerns behind earlier refusals been shared. This study yields a set of marketing implications. In particular, we show that observational learning and information sharing shape consumer choices in markedly different ways. Optimal marketing strategies should take into account how consumers learn from others.
Competition and Beyond: Problems and Attention Allocation in the Organizational Rulemaking Process
Authors: Sullivan Bilian Ni
Published: July 2009

This study investigates how an organization allocates attention and generates solutions in response to new problems challenging existing routines, under the influences of different contexts surrounding problems and solutions. By examining the formation of airline safety rules by the Federal Aviation Administration, I show that although different types of problems compete for attention at the rule proposal stage when the organization searches for solutions to problems, at the rule finalization stage, attention is guided by “urgency” induced by the aggregate flow of new problems, which interacts with certain institutional factors and with an a priori “priority” given to different types of rules. The implications of the study on theories of organizational attention are discussed.
Different Roles, Different Strokes: Organizing Virtual Customer Environments to Promote Two Types of Customer Contributions
Authors: Nambisan Satish , Baron Robert A.
Published: July 2009

In recent years, many companies have established virtual customer environments (VCEs) that offer facilities ranging from online discussion forums to virtual product design centers to partner with their customers in product development and product support activities. In this study, we focus on one form of VCE, online customer forums, and propose that the relevance of four distinct theoretical perspectives—social capital theory, social exchange theory, involvement, and social identity theory—to explaining customer participation will be contingent on the nature of the customer contribution context, that is, whether the contributions are to the customer community (through product support) or to the company (through product ideation). We propose a model suggesting that customers' prosocial behavior and expectations of private rewards will shape contributions to the community, whereas their perceived innovation partnership with the company and expectations of private rewards will shape a contribution to the company. We also contend that these effects will be moderated by customers' identification with the community and with the company. Our empirical findings offer support for the model and indicate that online customer forums (and more broadly VCEs) should be tailored to fit the nature of customer contribution sought. Implications for research and practice in customer co-innovation, online peer-to-peer communities, and customer relationship management are discussed.
A Case of Resistant Hypercalcemia of Malignancy with a Proposed Treatment Algorithm
Authors: McMahan Jonathan , Linneman Travis
Published: July 2009

Objective:

To report and describe a case of refractory hypercalcemia of malignancy (HCM) associated with metastatic, transitional-cell carcinoma of the left ureter.

Case Summary:

A 71-year-old male complaining of generalized weakness and night sweats for the past 3 months was sent to the emergency department when routine laboratory tests revealed a corrected serum calcium concentration of 14.4 mg/dL. Intravenous crystalloid fluids and pamidronate were administered with achievement of normocalcemia, and the patient was discharged. Computed tomography scan and liver biopsy revealed recurrent transitional-cell carcinoma with extensive liver metastasis. The patient returned approximately 1 week after discharge with a serum calcium level of 13.9 mg/dL. An initial decrease in serum calcium was observed with intravenous fluids, pamidronate, and calcitonin, but the normalization slowed and reversed within 3 days. Normocalcemia was achieved upon administration of zoledronic acid and the patient was discharged on day 14. The patient died 1 week after discharge from complications unrelated to hypercalcemia.

Discussion:

Hypercalcemia is common in patients with malignancy and is associated with potentially life-threatening sequelae. Four mechanisms of HCM have been recognized thus far, with ectopic tumor production of parathyroid hormone—related protein (PTHrP) being the leading cause. Treatment of HCM revolves around 2 principles; treatment of the underlying malignancy along with reduction of the serum calcium level. Evidence-based therapies for management include: intravenous crystalloid fluids with or without loop diuretics, bisphosphonates, calcitonin, gallium nitrate, and corticosteroids. Therapies used for this patient included aggressive hydration, calcitonin, and 3 distinct treatment courses of intravenous bisphosphonates with varying success. Other potential agents were explored for use in the event of continued hypercalcemia. These therapies remain viable options based on individual patient factors. To our knowledge, no published guidelines or algorithms exist for choosing between additional modalities in the treatment of refractory HCM.

Conclusions:

For patients with HCM who do not achieve a response from bisphosphonates, or for those who need repeated dosing more often than expected, changing to a different drug class could be an alternative. The specific mechanism of hypercalcemia should be considered when developing a treatment regimen for patients who have had a suboptimal response to initial therapy with bisphosphonates. Multiple treatment modalities exist for the treatment of hypercalcemia, each with a different mechanism of action. As with the treatment of other disease states, we can use this knowledge to more specifically target the mechanism of the patient's disease.
Denosumab in Osteoporosis and Oncology
Authors: Burkiewicz Jill S , Scarpace Sarah L , Bruce Susan P
Published: July 2009

Objective:

To review the pharmacology, pharmacokinetics, pharmacodynamics, safety, efficacy, and use of denosumab in osteoporosis, breast cancer, prostate cancer, and multiple myeloma.

Data Sources:

Studies and abstracts were identified through MEDLINE and International Pharmaceutical Abstracts (1966–July 2009). Key search terms include denosumab, AMG-162, and receptor activator of nuclear factor-κB ligand system. Information available in abstract form was retrieved from major oncology and bone metabolism meetings. Additional data were obtained from the manufacturer.

Study Selection and Data Extraction:

All available studies in humans were included except for studies in rheumatoid arthritis and giant cell tumor of the bone.

Data Synthesis:

In patients with osteoporosis, denosumab significantly reduces bone resorption and fractures. Studies of denosumab in the prevention and treatment of osteoporosis have demonstrated significantly increased bone mineral density and reduced bone turnover markers. Studies of denosumab versus placebo in the treatment of osteoporosis have demonstrated reductions in vertebral, hip, and nonvertebral fractures. In oncology, positive results from clinical trials in patients receiving endocrine therapy for breast and prostate cancer demonstrated decreases in bone loss and skeletal-related events. Denosumab seems to be at least as effective in reducing bone turnover markers as intravenous bisphosphonates in the oncology setting. The most common adverse effects in patients with osteoporosis were arthralgia, nasopharyngitis, back pain, and headache. The most common adverse effects in patients with cancer were infection, pain in the extremities, arthralgia, bone pain, fatigue, and pain. Serious adverse effects include infections requiring hospitalization.

Conclusions:

Denosumab has documented efficacy and safety in patients with osteoporosis, breast cancer, and prostate cancer. Additional clinical trial data are needed to more completely establish the effectiveness of denosumab in the treatment of osteoporosis and neoplastic disease as well as its cost-effectiveness and long-term safety.
Associations Among Therapist Beliefs, Personal Resources and Burnout in Clinical Psychologists
Authors: Emery Sally , Wade Tracey D. , McLean Sara
Published: July 2009

There were two aims of the research with 190 Australian clinical psychologists: (1) to investigate the construct validity of the Therapist Belief Scale (TBS), and (2) to examine the relative contribution of demographics, workplace variables, and individual factors to burnout. Construct validity was examined using exploratory and confirmatory factor analyses and associations between the variables. Multivariate regressions were used to examine the relative contributions to burnout. The TBS showed three factors related to distress, inflexibility, and control, all of which were significantly associated with lower levels of personal accomplishment. Multivariate analyses showed emotional exhaustion to be associated being a woman, working for the government, having less personal resources, and endorsing more therapist beliefs related to control. Higher levels of personal accomplishment were significantly associated with a lower annual income, not having a mixed caseload, having more personal resources, and endorsing lower levels of therapist beliefs related to inflexibility and control.
Synthesis of a lignin polymer model consisting of only phenolic β-O-4 linkages and testing its reactivity under alkaline conditions 10th EWLP, Stockholm, Sweden, August 25–28, 2008
Authors: Megiatto Jackson D. , Cazeils Emmanuel , Grelier Stéphane , Gardrat Christian , Ham-Pichavant Frédérique , Castellan Alain
Published: July 2009

A trimeric β-O-4 lignin model bearing a styrene unit was polymerized in the presence of azobisisobutyronitrile as an initiator of free radical polymerization. The polymer analysis achieved by size exclusion chromatography (SEC), 1H, 13C, 31P NMR, matrix-assisted laser desorption ionization combined with time-of-flight mass spectrometry (MALDI-ToF MS), differential scanning calorimetry, and thermogravimetry indicated its well-defined structure with good thermal stability at temperatures usually applied for alkaline pulping. SEC analysis proved a high degree of polymerization despite the size of the phenolic β-O-4 units in the polymer structure. MALDI-ToF spectrometry indicated that the polymer is composed of phenolic β-O-4 elements only. The chemical reactivity under alkaline conditions of the polymer was studied by both HPLC and 31P NMR. These two methods revealed two main concurrent processes, which include an oxidation of the phenol part followed by Cα-Cβ bond cleavage, and a formation of a quinone methide followed by its β-O-4 bond cleavage.
Material Variability and Repetitive Member Factors for the Allowable Properties of Engineered Wood Products
Authors: Verrill Steve , Kretschmann David E.
Published: July 2009

It has been argued that repetitive member allowable property adjustments should be larger for high-variability materials than for low-variability materials. We report analytic calculations and simulations that suggest that the order of such adjustments should be reversed, that is, given the manner in which allowable properties are currently calculated, as the coefficient of variation of the strength distribution of individual elements increases, the upward repetitive member adjustments (if any) of assemblies constructed from these elements should decrease.
Analyzing Settling of Fine-Grained Soil by Electrical Resistance Measurements
Authors: Verástegui Flores R. D. , Di Emidio G. , Van Impe W. F.
Published: July 2009

The industry and construction sector face an increasing problem of how to dispose of its voluminous residues. Much of these residues are constituted of large amounts of liquid phase and fine-grained solids in suspension, for example mine tailings and dredged materials. Therefore, there is a need to develop technologies that aim at reducing the volume of these residues for economical disposal or treatment. Depending on the type of solid and liquid phase, a number of additives are currently used to speed up the sedimentation and reduce the volume of these suspensions. In order to investigate the impact of different additives, a laboratory setup was designed to monitor the sedimentation process. This setup consists of a transparent plastic tube provided with electrodes. This paper focuses on the evaluation and performance of electrical resistance measurement as a means to monitor the sedimentation of a fine-grained soil. Experimental work was carried out on suspensions of kaolin clay in deionized water and electrolyte solutions. The results showed that electrical resistance measurements can provide valuable information related to densification and fabric of the soft sediment.
Ectopic Expression of Multiple Microbial Rhodopsins Restores ON and OFF Light Responses in Retinas with Photoreceptor Degeneration
Authors: Zhang Yi , Ivanova Elena , Bi Anding , Pan Zhuo-Hua
Published: July 2009

By expressing channelrhodopsin-2 (ChR2) in inner retinal neurons, previous studies have demonstrated restoration of ON responses in the retina after the death of rod and cone photoreceptors. In this study, we report that the expression of halorhodopsin (HaloR), a light-driven chloride pump, can effectively restore OFF responses in inner retinal neurons of mice with retinal degeneration. We show that HaloR-expressing retinal ganglion cells respond to light with rapid hyperpolarization and suppression of spike activity. After termination of the light stimulus, their membrane potential exhibits a rapid rebound overshoot with robust sustained or transient spike firing. Furthermore, we show that coexpression of ChR2/HaloR in retinal ganglion cells can produce ON, OFF, and even ON–OFF responses, depending on the wavelength of the light stimulus. Our results suggest that the expression of multiple microbial rhodopsins such as ChR2 and HaloR is a possible strategy to restore both ON and OFF light responses in the retina after the death of rod and cone photoreceptors.
Long-Lasting Working Memories of Obstacles Established by Foreleg Stepping in Walking Cats Require Area 5 of the Posterior Parietal Cortex
Authors: McVea David A. , Taylor Andrew J. , Pearson Keir G.
Published: July 2009

Walking animals rely on working memory to avoid obstacles. One example is the stepping of the hindlegs of quadrupeds over an obstacle. In this case, the obstacle is not visible at the time of hindleg stepping, because of its position between the fore and hindlegs, and working memory must be used to avoid it. We have previously shown that this memory is very precise and surprisingly long-lasting and that it depends on the stepping of the forelegs over the obstacle for its initiation. In this study, we test the hypothesis that area 5 in the posterior parietal cortex of cats is necessary for the maintenance of this long-lasting working memory. We report that small bilateral lesions to area 5 do not affect the amplitude of normal stepping of the hindlegs over obstacles, but they profoundly reduce the long-lasting working memory of obstacles. We propose that inputs to area 5 associated with foreleg stepping initiate long-lasting activity that maintains the memory of obstacle height in another brain region to guide the hindlegs over obstacles.
LRRK2 Modulates Vulnerability to Mitochondrial Dysfunction in Caenorhabditis elegans
Authors: Saha Shamol , Guillily Maria D. , Ferree Andrew , Lanceta Joel , Chan Diane , Ghosh Joy , Hsu Cindy H. , Segal Lilach , Raghavan Kesav , Matsumoto Kunihiro , Hisamoto Naoki , Kuwahara Tomoki , Iwatsubo Takeshi , Moore Landon , Goldstein Lee , Cookson Mark , Wolozin Benjamin
Published: July 2009

Mutations in leucine-rich repeat kinase 2 (LRRK2) cause autosomal-dominant familial Parkinson's disease. We generated lines ofCaenorhabditis elegansexpressing neuronally directed human LRRK2. Expressing human LRRK2 increased nematode survival in response to rotenone or paraquat, which are agents that cause mitochondrial dysfunction. Protection by G2019S, R1441C, or kinase-dead LRRK2 was less than protection by wild-type LRRK2. Knockdown of lrk-1, the endogenous ortholog of LRRK2 inC. elegans, reduced survival associated with mitochondrial dysfunction.C. elegansexpressing LRRK2 showed rapid loss of dopaminergic markers (DAT::GFP fluorescence and dopamine levels) beginning in early adulthood. Loss of dopaminergic markers was greater for the G2019S LRRK2 line than for the wild-type line. Rotenone treatment induced a larger loss of dopamine markers inC. elegansexpressing G2019S LRRK2 than inC. elegansexpressing wild-type LRRK2; however, loss of dopaminergic markers in the G2019S LRRK2 nematode lines was not statistically different from that in the control line. These data suggest that LRRK2 plays an important role in modulating the response to mitochondrial inhibition and raises the possibility that mutations in LRRK2 selectively enhance the vulnerability of dopaminergic neurons to a stressor associated with Parkinson's disease.
Intrapopulation niche partitioning in a generalist predator limits food web connectivity
Authors: Quevedo Mario , Svanbäck Richard , Eklöv Peter
Published: July 2009

Predators are increasingly recognized as key elements in food webs because of their ability to link the fluxes of nutrients and energy between spatially separated food chains. However, in the context of food web connectivity, predator populations have been mainly treated as homogeneous units, despite compelling evidence of individual specialization in resource use. It is conceivable that individuals of a predatory species use different resources associated with spatially separated food chains, thereby decoupling cross‐habitat linkages. We tested whether intrapopulation differences in habitat use in the generalist freshwater predator Eurasian perch (Perca fluviatilis) led to long‐term niche partitioning and affected the degree of ecological habitat coupling. We evaluated trophic niche variability at successively larger timescales by analyzing gut contents and stable isotopes (δ13C and δ15N) in liver and muscle, tissues that provide successively longer integration of trophic activity. We found that the use of distinct habitats in perch led to intrapopulation niche partitioning between pelagic and littoral subpopulations, consistent through the various timescales. Pelagic fish showed a narrower niche, lower individual specialization, and more stable trophic behavior than littoral fish, as could be expected from inhabiting a relatively less diverse environment. This result indicated that substantial niche reduction could occur in a generalist predator at the subpopulation level, consistent with the use of a habitat that provides fewer chances of individual specialization. We showed that intrapopulation niche partitioning limits the ability of individual predators to link spatially separated food chains. In addition, we suggest a quantitative, standardized approach based on stable isotopes to measure the degree of habitat coupling mediated by a top predator.
Contrasts between habitat generalists and specialists: an empirical extension to the basic metacommunity framework
Authors: Pandit Shubha N. , Kolasa Jurek , Cottenie Karl
Published: July 2009

Emergence of the metacommunity concept has made a substantial contribution to better understanding of the community composition and dynamics in a regional context. However, long‐term field data for testing of available metacommunity models are still scarce, and the extent to which these models apply to the real world remains unknown. Tests conducted so far have largely sought to fit data on the entire regional set of species to one of several metacommunity models, implicitly assuming that all species operate similarly over the same set of sites. However, species differ in their habitat use. These differences can, in the most general terms, be expressed as a gradient of habitat specialization (ranging from habitat specialists to habitat generalists). We postulate that such differences in habitat specialization will have implications for metacommunity dynamics. Specifically, we predict that specialists respond more to local processes and generalists respond to regional spatial processes. We tested these predictions using natural microcosm communities for which long‐term (nine‐year) environmental and population dynamics data were available. We used redundancy analysis to determine the proportion of variation explained by environmental and spatial factors. We repeated this analysis to explain variation in the entire regional set of species, in generalist species only, and in specialists only. We further used ANOVA to test for differences in the proportions of explained variation. We found that habitat specialists responded primarily to environmental factors and habitat generalists responded mainly to spatial factors. Thus, from the metacommunity perspective, the dynamics of habitat specialists are best explained by a combination of species sorting and mass effects, while that of habitat generalists are best explained by patch dynamics and neutral models. Consequently, we infer that a natural metacommunity can exhibit complicated dynamics, with some groups of species (e.g., habitat specialists) governed according to environmental processes and other groups (e.g., habitat generalists) governed mainly by dispersal processes.
Modeling the flow of 15N after a 15N pulse to study long‐term N dynamics in a semiarid grassland
Authors: Dijkstra Feike A.
Published: July 2009

Many aspects of nitrogen (N) cycling in terrestrial ecosystems remain poorly understood. Progress in studying N cycling has been hindered by a lack of effective measurements that integrate processes such as denitrification, competition for N between plants and microbes, and soil organic matter (SOM) decomposition over large time scales (years rather than hours or days). Here I show how long‐term measurements of 15N in plants, microbes, and soil after a one‐time addition of 15N (“labeled” N) can provide powerful information about long‐term N dynamics in a semiarid grassland. I develop a simple dynamic model and show that labeled‐N fractions in plant and microbial‐N pools (expressed as a fraction of total N in each pool) can change long after 15N application (≥5 years). These 15N dynamics are closely tied to the turnover times of the different N pools. The model accurately simulated the labeled‐N fractions in aboveground biomass measured annually during five years after addition of 15N to a semiarid grassland. I also tested the sensitivity of five different processes on labeled‐N fractions in aboveground plant biomass. Changing plant/microbial competition for N had very little effect on the labeled‐N fraction in aboveground biomass in the short and long term. Changing microbial activity (N mineralization and immobilization), N loss, or N resorption/re‐translocation by plants affected the labeled‐N fraction in the short term, but not in the long term. Large long‐term effects on the labeled‐N fraction in aboveground biomass could only be established by changing the size of the active soil‐N pool. Therefore, the significantly greater long‐term decline in the labeled‐N fraction in aboveground biomass observed under elevated CO2 in this grassland system could have resulted from an increased active soil‐N pool under elevated CO2 (i.e., destabilization of soil organic matter that was relatively recalcitrant under ambient CO2 conditions). I conclude that short‐ and long‐term labeled‐N fractions in plant biomass after a 15N pulse are sensitive to processes such as N mineralization and immobilization, N loss, and soil organic matter (de‐)stabilization. Modeling these fractions provides a useful tool to better understand N cycling in terrestrial ecosystems.
Safe sites, seed supply, and the recruitment function in plant populations
Authors: Duncan Richard P. , Diez Jeffrey M. , Sullivan Jon J. , Wangen Steven , Miller Alice L.
Published: July 2009

The extent to which plant populations are seed vs. establishment limited can be understood by quantifying the recruitment function, describing the number of seedlings that establish as a function of the number of seeds added. Here, we derive a general equation for the recruitment function based on a mechanistic model describing how the availability of safe sites (sites suitable for germination and establishment) interacts with the number and distribution of seeds added to a plot to determine the number of recruits. The parameters of this recruitment function have a direct biological interpretation that can provide insight into the processes limiting recruitment in plant populations.
Forest carbon storage: ecology, management, and policy
Authors: Fahey Timothy J , Woodbury Peter B , Battles John J , Goodale Christine L , Hamburg Steven P , Ollinger Scott V , Woodall Christopher W
Published: July 2009

The objective of this review is to give ecologists and policy makers a better understanding of forest carbon dynamics and recent policy and management activities in this arena. The ecology of forest carbon is well understood, but measurement and projection of carbon sequestration at small scales can be costly. Some forest management activities qualify as offsets in various carbon markets. To promote wider use, a system is needed that will provide inexpensive and standardized approaches to forest carbon accounting that are not prone to dishonest handling. The prospects are fairly promising for development of such a system, but first, technical and organizational constraints must be overcome. In contrast, the benefits – in terms of greenhouse‐gas reduction – of substituting wood for other building materials, and in displacing fossil fuel energy, could be realized immediately, if standards for calculations can be developed.
Minimization of Financial Losses due to Voltage Sag in an Indian Distribution System using D-STATCOM
Authors: Goswami Arup Kumar , Gupta Chandra Prakash , Singh Girish Kumar
Published: July 2009

Voltage sag can cause considerable financial damage in an industry containing sensitive equipment. Many solutions exist to minimize financial losses due to voltage sag, varying from modification within the process itself to restructuring the supplying grid. In many cases the only possibility to minimize the financial losses is to install mitigation devices between the grid and the sensitive process such as power electronics devices Uninterruptible Power Supply (UPS). However, protecting the entire process by a dynamic or static UPS often turns out to be too expensive. This paper presents the minimization of financial losses due to voltage sag produced by balanced and unbalanced short circuit that occur at distribution system bus and along the transmission line using system impedance matrix (Z Bus) which incorporates D-STATCOM. The overall financial losses due to voltage sag could significantly change depending on the location of D-STATCOM used. In order to have an assessment of financial losses in real distribution systems, the classical static fault calculation should be amended to incorporate the effect of installation of these devices on financial losses. The cost-benefit analyses of inducting D-STATCOM for mitigating the effects of voltage sags have also been performed.Case studies based on a real Indian distribution system are used to illustrate the modeling method and the effectiveness of these devices in voltage sag mitigation.
Associations Between Dietary Fiber and Inflammation, Hepatic Function, and Risk of Type 2 Diabetes in Older Men
Authors: Wannamethee S. Goya , Whincup Peter H. , Thomas Mary C. , Sattar Naveed
Published: July 2009

OBJECTIVE

To examine the relationship between dietary fiber and the risk of type 2 diabetes in older men and the role of hepatic and inflammatory markers.

RESEARCH DESIGN AND METHODS

The study was performed prospectively and included 3,428 nondiabetic men (age 60–79 years) followed up for 7 years, during which there were 162 incident cases of type 2 diabetes.

RESULTS

Low total dietary fiber (lowest quartile ≤20 g/day) was associated with increased risk of diabetes after adjustment for total calorie intake and potential confounders (relative risk −1.47 [95% CI 1.03–2.11]). This increased risk was seen separately for both low cereal and low vegetable fiber intake. Dietary fiber was inversely associated with inflammatory markers (C-reactive protein, interleukin-6) and with tissue plasminogen activator and γ-glutamyl transferase. Adjustment for these markers attenuated the increased risk (1.28 [0.88–1.86]).

CONCLUSIONS

Dietary fiber is associated with reduced diabetes risk, which may be partly explained by inflammatory markers and hepatic fat deposition.
Traumatic Brain Injury and Vestibular Pathology as a Comorbidity After Blast Exposure
Authors: Scherer Matthew R. , Schubert Michael C.
Published: July 2009

Blasts or explosions are the most common mechanisms of injury in modern warfare. Traumatic brain injury (TBI) is a frequent consequence of exposure to such attacks. Although the management of orthopedic, integumentary, neurocognitive, and neurobehavioral sequelae in survivors of blasts has been described in the literature, less attention has been paid to the physical therapist examination and care of people with dizziness and blast-induced TBI (BITBI). Dizziness is a common clinical finding in people with BITBI; however, many US military service members who have been exposed to blasts and who are returning from Iraq and Afghanistan also complain of vertigo, gaze instability, motion intolerance, and other symptoms consistent with peripheral vestibular pathology. To date, few studies have addressed such “vestibular” complaints in service members injured by blasts. Given the demonstrated efficacy of treating the signs and symptoms associated with vestibular pathology, vestibular rehabilitation may have important implications for the successful care of service members who have been injured by blasts and who are complaining of vertigo or other symptoms consistent with vestibular pathology. In addition, there is a great need to build consensus on the clinical best practices for the assessment and management of BITBI and blast-related dizziness. The purpose of this review is to summarize the findings of clinicians and scientists conducting research on the effects of blasts with the aims of defining the scope of the problem, describing and characterizing the effects of blasts, reviewing relevant patients’ characteristics and sensorimotor deficits associated with BITBI, and suggesting clinical best practices for the rehabilitation of BITBI and blast-related dizziness.
Transnational Families Under Siege
Authors: Naber Nadine
Published: July 2009

This article is based on ethnographic research among southern Lebanese in Dearborn, Michigan, in the aftermath of the 2006 war in Lebanon. It focuses on the significance of family and gender in the intensification of long-distance nationalism among Lebanese in diaspora. The war inspired a sense of belonging to a transnational Lebanese family under siege. This naturalized the practice of “comfort mothering,” which met the emotive needs of a diaspora engaged from a distance with a war in the homeland. The paper explores how concepts and practices of belonging to a transnational “Arab family” placed a double duty on women activists in official Arab American public politics. Engagements with normative concepts of belonging to an “American family” entailed a gendered strategy of resistance in which Arab American official politics deployed women’s narratives to humanize the Lebanese in the face of a “war on terror” discourse that conflated Lebanese Shi‘ite masculinity with Hizballah and terrorism. This essay aims to expand theories on the intersections between gender and nation in light of transnational experiences of war. It also questions the expansiveness of intersectionality in light of a collective experience of military invasion in which the urgency of war overdetermines the significance of other forms of oppression, including gender oppression.
Clinically silent magnetic resonance imaging findings after subdural strip electrode implantation
Authors: Al-Otaibi Faisal A. J. , Alabousi Abdullah , Burneo Jorge G. , Lee Donald H. , Parrent Andrew G. , Steven David A.
Published: July 2009

Object

Subdural strip electrodes (SSEs) are often used as part of the workup in patients being considered for epilepsy surgery. To assess for complications or to confirm electrode placement, postoperative imaging is often performed. Imaging performed with the electrodes in situ is limited by streak artifact on CT and susceptibility artifact on MR imaging. Therefore, the first opportunity for high-quality postoperative imaging is following explantation of electrodes. There is no data available to determine what would be the expected MR imaging appearance following insertion of SSE. The purpose of this study is to describe the MR imaging findings in asymptomatic patients who underwent insertion of SSEs.

Methods

Twenty consecutive patients who underwent SSE insertion were studied. Within 24 hours after removal of the electrodes, each patient underwent MR imaging that included axial T2-weighted, gradient echo, diffusion weighted, and coronal FLAIR sequences. No significant symptoms were reported by any of the patients. The studies were reviewed by an experienced, blinded neuroradiologist and categorized.

Results

Of the 20 patients studied, 11 were female (mean age 36 years). Clinically silent postexplantation MR imaging abnormalities were found in all patients: subdural hematomas in 7 (35%), cortical contusions in 5 (25%), local edema in 5 (25%), trans–bur hole cortical herniation in 5 (25%), subdural hygromas in 2 (10%), and pneumocranium in 4 (20%). The MR imaging abnormalities were subdivided into 2 types: Type A, abnormalities related to the site of electrode insertion; and Type B, abnormalities related to the location of the electrodes. The most common location for a Type A abnormality was occipitotemporal, with cortical contusions occurring in this location in 18% of cases, local edema in 24%, and trans–bur hole herniation in 24%. The next most common location was frontal, with cortical contusions found in this location in 10% of cases, local edema in 5% and trans–bur hole herniation in 5%. The most common Type B abnormality was a subdural hematoma, followed by pneumocranium and subdural hygroma.

Conclusions

Clinically silent MR imaging abnormalities are common following SSE placement. Knowledge of these findings would be of assistance in interpreting MR imaging results in patients being assessed for complications.
Ecological Restoration and Place Attachment: Emplacing Non-Places?
Authors: Drenthen Martin
Published: July 2009

The creation of new wetlands along rivers as an instrument to mitigate flood risks in times of climate change seduces us to approach the landscape from a ‘managerial’ perspective and threatens a more place-oriented approach. How to provide ecological restoration with a broad cultural context that can help prevent these new landscapes from becoming non-places, devoid of meaning and with no real connection to our habitable world. In this paper, I discuss three possible alternative interpretations of the meaning of places and place attachment in these ‘new nature’ projects, and show how all three imply a different view on human identity and history.
Goodwill toward Nature
Authors: Freiman Christopher
Published: July 2009

It is sometimes claimed that an ethical relationship with nature is analogous to Aristotelian friendship. Aristotle claims that friends are valuable principally in virtue of providing reflections of ourselves; yet extant accounts of environmental friendship do not explain how nonhuman organisms can satisfy this role. Recent work in neo-Aristotelian metaethics delineates a theory of value that underscores the similarities between the biological evaluations we make of living things and the moral evaluations we make of ourselves. I argue that these similarities help us make sense of the claim that nonhuman organisms can be reflections of ourselves and thus the object of a relationship akin to friendship. I conclude by suggesting that Aristotle's conception of goodwill may be even more appropriate than friendship as a model for a virtuous relationship with nature.
World Poverty, Animal Minds and the Ethics of Veterinary Expenditure
Authors: Hadley John , Sullivan Siobhan O’
Published: July 2009

In this paper we make an argument for limiting veterinary expenditure on companion animals. The argument combines two principles: the obligation to give and the self-consciousness requirement. In line with the former, we ought to give money to organisations helping to alleviate preventable suffering and death in developing countries; the latter states that it is only intrinsically wrong to painlessly kill an individual that is self-conscious. Combined, the two principles inform an argument along the following lines: rather than spending inordinate amounts of money on veterinary care when a companion animal is sick or injured, it is better to give the money to an aid organisation and painlessly kill the animal.
Cultural Danger of Globalisation for the Islamic World
Authors: Bakr Rafique Abu
Published: July 2009

The full text of this article is in Arabic - see PDF below.doi: 10.3329/iiucs.v4i0.2858 IIUC STUDIES Vol. - 4, December 2007 (p 49-58)
Arabic dialect and its relation with Arabic language
Authors: Uddin Shofi
Published: July 2009

The full text of this article is in Arabic - see PDF below.doi: 10.3329/iiucs.v4i0.2863 IIUC STUDIES Vol. - 4, December 2007 (p 75-96)
Originality and modernity in Islamic Jurisprudence
Authors: Nadwi AR
Published: July 2009

The full text of this article is in Arabic - see PDF below.doi: 10.3329/iiucs.v4i0.2864 IIUC STUDIES Vol. - 4, December 2007 (p 97-120)
Orientalists position in compiling the Holy Quran
Authors: Jahed M Rasheid
Published: July 2009

The full text of this article is in Arabic - see PDF below.doi: 10.3329/iiucs.v4i0.2865 IIUC STUDIES Vol. - 4, December 2007 (p 121-144)
On the legitimacy of the vision Murabaha and formulation of the bank
Authors: Rahman Mofizur
Published: July 2009

The full text of this article is in Arabic - see PDF below.doi: 10.3329/iiucs.v4i0.2867 IIUC STUDIES Vol. - 4, December 2007 (p 169-196)
Clinical Profile of Diabetes Mellitus in Children and Adolescents under Eighteen Years of Age
Authors: Mohsin Fauzia , Zabeen Bedowra , Zinnat Rahelee , Azad Kishwar , Nahar Nazmun
Published: July 2009

A total number of 125 patients with diabetes mellitus (DM) under eighteen years of age were admitted in the Paediartic department of BIRDEM hospital between January 2001 to October 2002. Eighty-eight patients (71%) were newly detected. Female to male ratio was 3:1. Out of the total admission 38 (30.4%) patients had type 1 DM (group 1), 37 (29.6%) patients had fibrocalculous pancreatic FCPD diabetes (group II), 48 (38.4%) patient had malnutrition modulated diabetes mellitus MMDM (group III) and 2 (1.6%) patients had type 2. Mean age of onset was 9±3.9 yrs in group I and 13±2.3 yrs in group II and group III. All groups had very high glucose and HbA1c value at presentation. The mean fasting glucose (mmol/l) was 19±7.14, 22.39±9 and 19.54±7.9 in group I, group II and group III respectively. The Mean HbA1c (%) value in the three groups was 14.4±2.7, 16.72±2.26 and 15.27±3.05 respectively. FCPD patients had poorest glycaemic status. Acute complications were more common in type 1 patients. Twelve (31.5%) patients had diabetic ketoatin DKA and two (5%) patients had hypoglycaemia in group I. Chronic complications were present in all three groups. MMDM patients had highest rate of complications. which was present in 2.6%, 21.6% and 33.3% patients in group I, group II and group III respectively. The rate of microalbuminuria was 5.3%. 10.8% and 18.8% in the three groups respectively. The rate of neuropathy was 2.6%, 16.2% and 20.8% in the three groups respectively. Among the associated problems skin infection, pulmonary tuberculosis and bilateral parotid swelling were common. Malnutrition was present in 66%, 86% and 100% in group I, group II and group III respectively. Majority (50% in group I, 91.6% in group II and 100% in group III) of our patients came from poor socio-economic background. Ibrahim Med. Coll. J. 2007; 1(1): 11-15       Key words: Diabetes mellitus doi: 10.3329/imcj.v1i1.2889
Biodegradable Polymers in Bone Tissue Engineering
Authors: Kroeze Robert  J. , Helder Marco  N. , Govaert Leon  E. , Smit Theo  H.
Published: July 2009

The use ofdegradable polymers in medicine largely started around the mid 20th century with their initial use as in vivo resorbing sutures. Thorough knowledge on this topic as been gained since then and the potential applications for these polymers were, and still are, rapidly expanding. After improving the properties of lactic acid-based polymers, these were no longer studied only from a scientific point of view, but also for their use in bone surgery in the 1990s. Unfortunately, after implanting these polymers, different foreign body reactions ranging from the presence of white blood cells to sterile sinuses with resorption of the original tissue were observed. This led to the misconception that degradable polymers would, in all cases, lead to inflammation and/or osteolysis at the implantation site. Nowadays, we have accumulated substantial knowledge on the issue of biocompatibility of biodegradable polymers and are able to tailor these polymers for specific applications and thereby strongly reduce the occurrence of adverse tissue reactions. However, the major issue of biofunctionality, when mechanical adaptation is taken into account, has hitherto been largely unrecognized. A thorough understanding of how to improve the biofunctionality, comprising biomechanical stability, but also visualization and sterilization of the material, together with the avoidance of fibrotic tissue formation and foreign body reactions, may greatly enhance the applicability and safety of degradable polymers in a wide area of tissue engineering applications. This review will address our current understanding of these biofunctionality factors, and will subsequently discuss the pitfalls remaining and potential solutions to solve these problems.
Physical Carboxymethylscleroglucan/Calcium Ion Hydrogels as Modified Drug Delivery Systems in Topical Formulations
Authors: Corrente Federica , Matricardi Pietro , Paolicelli Patrizia , Tita Beatrice , Vitali Federica , Casadei Maria Antonietta
Published: July 2009

A carboxymethyl derivative of scleroglucan (Scl-CM) with a 65±5% carboxylic group degree of derivatization (DD) was recently synthesized and characterized. Aqueous solutions of the polymer underwent to a sharp transition toward a gel like behaviour in the presence of divalent ions such as Ca+2. Physical hydrogels with different Scl-CM/Ca+2 ratios were prepared and characterized for their rheological behaviour. Their potential as drug delivery systems was also evaluated. To this end three non steroidal anti-inflammatory drugs (NSAIDs) were loaded into the hydrogels obtained with 2% w/v solution of Scl-CM and 0.05 and 0.1 M CaCl2. The release rate of the drugs was critically related to the salt concentration. By an appropriate combination of the hydrogels prepared using different amounts of salt, it was possible to obtain a system able to release diclofenac with zero-order kinetics. Primary skin irritation tests showed a good biocompatibility of the new polymer, as well as of its hydrogels. These results suggest a potential of the new hydrogels for the development of modified delivery systems in topical formulations.
Neurotrophism of Bone Marrow Stromal Cells to Embryonic Stem Cells: Noncontact Induction and Transplantation to a Mouse Ischemic Stroke Model
Authors: Yang Tao , Tsang Kam Sze , Poon Wai Sang , Ng Ho Keung
Published: July 2009

Embryonic stem (ES) cell-derived cell products may serve as a source of cells for regenerative medicine. Currently available technologies for the induction of ES cells into neural lineage cells require extended culturing in vitro and complex procedural manipulations, with variable yields of heterogeneous cells, which have hindered the prospective use of cell derivatives for treatment of ischemic stroke. We established a simple and efficient method to derive mouse ES cells into neural lineage cells using an 8-day coculture with the bone marrow stromal cells MS5, followed by a 6-day propagation culture and a 4-day selection culture. The protocol generated a relatively high yield of neural lineage cells without any mesodermal and endodermal lineage commitment. In in vivo study, these derived cells could improve the cognitive function of ischemic stroke mice. Three weeks after transplantation, migration of implanted cells to lesioned areas was noted. It was also evident of a normalization of pyramidal neuron density and morphology in hippocampal CA1 region. One (1/17) episode of teratoma development was noted. Data suggested that MS5 cells may exert a neurotrophic effect to enhance neural differentiation of ES cells and MS5-induced ES cell-derived cells appeared to be applicable to cell therapy for ischemic stroke.