bluuebunny/crossref_metadata_2025 huggingface dataset:
Prevalence and patterns of multimorbidity among the elderly in Burkina Faso: cross‐sectional study
Authors: Hien Hervé , Berthé Abdramane , Drabo Maxime Koiné , Meda Nicolas , Konaté Blahima , Tou Fatoumata , Badini‐Kinda Fatoumata , Macq Jean
Published: August 2014

Objectives

To assess the prevalence and distribution patterns of multimorbidity among urban older adults in Burkina Faso.

Methods

Cross‐sectional study among community‐dwelling elderly people aged ≥60 in Bobo‐Dioulasso. We performed interviews, clinical examination and medical record review. Multimorbidity was defined as co‐occurrence of at least two chronic diseases in one person whether as a coincidence or not.

Results

The overall prevalence of multimorbidity among older adults was 65%. Age ≥70 was associated with multimorbidity in multivariate analysis: adjusted OR = 1.65, 95% CI (1.01–2.68, P = 0.04). The most common chronic diseases were hypertension (82%) 95% CI (78; 86), malnutrition (39%) 95% CI (34; 44), visual impairments (28%) 95% CI (24; 33) and diabetes mellitus (27%) 95% CI (22; 31). Those aged ≥70 had significantly more malnutrition (50% vs. 31%, P = 0.0003) and osteoarthritis (8% vs. 3%, P = 0.01) than those aged 60–69.

Conclusions

The high prevalence of multimorbidity requires a reorganization of healthcare systems in sub‐Saharan Africa, especially in Burkina Faso. Interventions and care guidelines usually focused on individual diseases should be improved to better reflect this reality.
The effect of plasmapheresis on blood pressure in voluntary plasma donors
Authors: Rosa‐Bray M. , Wisdom C. , Marier J. F. , Mouksassi M.‐S. , Wada S.
Published: August 2014

Background and Objectives

Donor plasmapheresis involves the removal of a weight‐adjusted volume of plasma and the return of cellular components to the donor. Although plasma volume generally returns to normal, some residual effect on vital signs may be possible. This analysis was performed to determine the possible effects of plasmapheresis on blood pressure.

Materials and Methods

A 16‐week study was conducted to evaluate the effects of plasma donations on cholesterol levels in healthy donors. From this study, the vital signs obtained prior to donation were analysed using statistical and dynamic analytical predictive models.

Results

Preliminary analyses revealed a change in systolic and diastolic blood pressure from the corresponding baseline values (Pearson Coefficient −0·44 and −0·47, respectively). Statistical models predicted a marked decrease in systolic and diastolic blood pressure following multiple donations in donors with baseline pressure in the Stage 2 hypertension range with less pronounced decreases predicted in Stage 1 donors. Little or no change in blood pressure was predicted in donors with baseline normal blood pressure or prehypertension. Dynamic models including time between donations supported these results and predicted a recovery period of about 14 days without donation in donors with Stage 2 baseline levels.

Conclusions

Results suggest that systolic and diastolic blood pressure may be decreased following plasmapheresis used for plasma donations at intervals of <14 days in donors with high baseline blood pressure levels.
Influence of cutting time and stubble height on regrowth capacity of Juncus effusus and Juncus conglomeratus
Authors: Kaczmarek‐Derda W , Folkestad J , Helgheim M , Netland J , Solhaug K A , Brandsæter L O
Published: August 2014

Infestation by Juncus effusus and Juncus conglomeratus causes a serious reduction in forage quality along the western coastline in Norway. Timing of treatments, for example cutting to reduce photosynthate return to the weeds, is crucial for successful and cost‐effective weed control. However, the effect may depend on changes in regrowth capacity over the growing season. A growth chamber experiment was conducted to investigate the effect of cutting time and stubble height on the regrowth capacity of J. effusus and J. conglomeratus from western and eastern Norway. Tussocks were collected from extensively managed pastures at 4‐ and 6‐week intervals in 2009 and 2010, respectively. The plants were potted, cut at 1 or 5 cm and exposed to three different temperatures (7.5, 12.5 and 17.5°C) in 2009 and to 17.5°C only in 2010. The regrowth ability was evaluated after 6 weeks by measuring stem number and dry biomass from old mowed and new shoots. Regrowth increased more with temperature for the eastern than for the western ecotype of J. effusus. Cutting to 1 cm stubble height gave substantially less regrowth than 5 cm cutting, both for dry biomass and number of shoots in both years. Regrowth varied significantly with date of cut and was lowest in late summer (mid‐July–August). This suggests that weeding strategies based on low cutting and mowing rush tussocks in late summer will be most effective, due to the low regrowth capacity.
Lattices in products of trees and a theorem of H. C. Wang
Authors: Burger Marc , Mozes Shahar
Published: August 2014

We study cocompact lattices with dense projections in a product of locally compact groups and show, under the assumption that each is a closed subgroup of the automorphism group of a regular tree satisfying certain local transitivity conditions, that such a lattice is contained in only finitely many discrete subgroups of .
Secondary neutron spectrum from 250‐MeV passively scattered proton therapy: Measurement with an extended‐range Bonner sphere system
Authors: Howell Rebecca M. , Burgett E. A.
Published: August 2014

Purpose:

Secondary neutrons are an unavoidable consequence of proton therapy. While the neutron dose is low compared to the primary proton dose, its presence and contribution to the patient dose is nonetheless important. The most detailed information on neutrons includes an evaluation of the neutron spectrum. However, the vast majority of the literature that has reported secondary neutron spectra in proton therapy is based on computational methods rather than measurements. This is largely due to the inherent limitations in the majority of neutron detectors, which are either not suitable for spectral measurements or have limited response at energies greater than 20 MeV. Therefore, the primary objective of the present study was to measure a secondary neutron spectrum from a proton therapy beam using a spectrometer that is sensitive to neutron energies over the entire neutron energy spectrum.

Methods:

The authors measured the secondary neutron spectrum from a 250‐MeV passively scattered proton beam in air at a distance of 100 cm laterally from isocenter using an extended‐range Bonner sphere (ERBS) measurement system. Ambient dose equivalent H*(10) was calculated using measured fluence and fluence‐to‐ambient dose equivalent conversion coefficients.

Results:

The neutron fluence spectrum had a high‐energy direct neutron peak, an evaporation peak, a thermal peak, and an intermediate energy continuum between the thermal and evaporation peaks. The H*(10) was dominated by the neutrons in the evaporation peak because of both their high abundance and the large quality conversion coefficients in that energy interval. The H*(10) 100 cm laterally from isocenter was 1.6 mSv per proton Gy (to isocenter). Approximately 35% of the dose equivalent was from neutrons with energies ≥20 MeV.

Conclusions:

The authors measured a neutron spectrum for external neutrons generated by a 250‐MeV proton beam using an ERBS measurement system that was sensitive to neutrons over the entire energy range being measured, i.e., thermal to 250 MeV. The authors used the neutron fluence spectrum to demonstrate experimentally the contribution of neutrons with different energies to the total dose equivalent and in particular the contribution of high‐energy neutrons (≥20 MeV). These are valuable reference data that can be directly compared with Monte Carlo and experimental data in the literature.
Reduction of ring artifacts in CBCT: Detection and correction of pixel gain variations in flat panel detectors
Authors: Altunbas Cem , Lai Chao‐Jen , Zhong Yuncheng , Shaw Chris C.
Published: August 2014

Purpose:

In using flat panel detectors (FPD) for cone beam computed tomography (CBCT), pixel gain variations may lead to structured nonuniformities in projections and ring artifacts in CBCT images. Such gain variations can be caused by change in detector entrance exposure levels or beam hardening, and they are not accounted by conventional flat field correction methods. In this work, the authors presented a method to identify isolated pixel clusters that exhibit gain variations and proposed a pixel gain correction (PGC) method to suppress both beam hardening and exposure level dependent gain variations.

Methods:

To modulate both beam spectrum and entrance exposure, flood field FPD projections were acquired using beam filters with varying thicknesses. “Ideal” pixel values were estimated by performing polynomial fits in both raw and flat field corrected projections. Residuals were calculated by taking the difference between measured and ideal pixel values to identify clustered image and FPD artifacts in flat field corrected and raw images, respectively. To correct clustered image artifacts, the ratio of ideal to measured pixel values in filtered images were utilized as pixel‐specific gain correction factors, referred as PGC method, and they were tabulated as a function of pixel value in a look‐up table.

Results:

0.035% of detector pixels lead to clustered image artifacts in flat field corrected projections, where 80% of these pixels were traced back and linked to artifacts in the FPD. The performance of PGC method was tested in variety of imaging conditions and phantoms. The PGC method reduced clustered image artifacts and fixed pattern noise in projections, and ring artifacts in CBCT images.

Conclusions:

Clustered projection image artifacts that lead to ring artifacts in CBCT can be better identified with our artifact detection approach. When compared to the conventional flat field correction method, the proposed PGC method enables characterization of nonlinear pixel gain variations as a function of change in x‐ray spectrum and intensity. Hence, it can better suppress image artifacts due to beam hardening as well as artifacts that arise from detector entrance exposure variation.
In vitro dose measurements in a human cadaver with abdomen/pelvis CT scans
Authors: Zhang Da , Padole Atul , Li Xinhua , Singh Sarabjeet , Khawaja Ranish Deedar Ali , Lira Diego , Liu Tianyu , Shi Jim Q. , Otrakji Alexi , Kalra Mannudeep K. , Xu X. George , Liu Bob
Published: August 2014

Purpose:

To present a study of radiation dose measurements with a human cadaver scanned on a clinical CT scanner.

Methods:

Multiple point dose measurements were obtained with high‐accuracy Thimble ionization chambers placed inside the stomach, liver, paravertebral gutter, ascending colon, left kidney, and urinary bladder of a human cadaver (183 cm in height and 67.5 kg in weight) whose abdomen/pelvis region was scanned repeatedly with a multidetector row CT. The flat energy response and precision of the dosimeters were verified, and the slight differences in each dosimeterˈs response were evaluated and corrected to attain high accuracy. In addition, skin doses were measured for radiosensitive organs outside the scanned region with OSL dosimeters: the right eye, thyroid, both nipples, and the right testicle. Three scan protocols were used, which shared most scan parameters but had different kVp and mA settings: 120‐kVp automA, 120‐kVp 300 mA, and 100‐kVp 300 mA. For each protocol three repeated scans were performed.

Results:

The tube starting angle (TSA) was found to randomly vary around two major conditions, which caused large fluctuations in the repeated point dose measurements: for the 120‐kVp 300 mA protocol this angle changed from approximately 110° to 290°, and caused 8% − 25% difference in the point dose measured at the stomach, liver, colon, and urinary bladder. When the fluctuations of the TSA were small (within 5°), the maximum coefficient of variance was approximately 3.3%. The soft tissue absorbed doses averaged from four locations near the center of the scanned region were 27.2 ± 3.3 and 16.5 ± 2.7 mGy for the 120 and 100‐kVp fixed‐mA scans, respectively. These values were consistent with the corresponding size specific dose estimates within 4%. The comparison of the per‐100‐mAs tissue doses from the three protocols revealed that: (1) dose levels at nonsuperficial locations in the TCM scans could not be accurately deduced by simply scaling the fix‐mA doses with local mA values; (2) the general power law relationship between dose and kVp varied from location to location, with the power index ranged between 2.7 and 3.5. The averaged dose measurements at both nipples, which were about 0.6 cm outside the prescribed scan region, ranged from 23 to 27 mGy at the left nipple, and varied from 3 to 20 mGy at the right nipple over the three scan protocols. Large fluctuations over repeated scans were also observed, as a combined result of helical scans of large pitch (1.375) and small active areas of the skin dosimeters. In addition, the averaged skin dose fell off drastically with the distance to the nearest boundary of the scanned region.

Conclusions:

This study revealed the complexity of CT dose fluctuation and variation with a human cadaver.
A study of the short‐ to long‐phantom dose ratios for CT scanning without table translation
Authors: Li Xinhua , Zhang Da , Yang Jie , Liu Bob
Published: August 2014

Purpose:

For CT scanning in the stationary‐table modes, AAPM Task Group 111 proposed to measure the midpoint dose on the central and peripheral axes of sufficiently long phantoms. Currently, a long cylindrical phantom is usually not available in many clinical facilities. The use of a long phantom is also challenging because of the heavy weight. In order to shed light on assessing the midpoint dose in CT scanning without table movement, the authors present a study of the short‐ to long‐phantom dose ratios, and perform a cross‐comparison of CT dose ratios on different scanner models.

Methods:

The authors performed Geant4‐based Monte Carlo simulations with a clinical CT scanner (Somatom Definition dual source CT, Siemens Healthcare), and modeled dosimetry measurements using a 0.6 cm3 Farmer type chamber and a 10‐cm long pencil ion chamber. The short (15 cm) to long (90 cm) phantom dose ratios were computed for two PMMA diameters (16 and 32 cm), two phantom axes (the center and the periphery), and a range of beam apertures (3–25 cm). The results were compared with the published data of previous studies with other multiple detector CT (MDCT) scanners and cone beam CT (CBCT) scanners.

Results:

The short‐ to long‐phantom dose ratios changed with beam apertures but were insensitive to beam qualities (80–140 kV, the head and body bowtie filters) and MDCT and CBCT scanner models.

Conclusions:

The short‐ to long‐phantom dose ratios enable medical physicists to make dosimetry measurements using the standard CT dosimetry phantoms and a Farmer chamber or a 10 cm long pencil chamber, and to assess the midpoint dose in long phantoms. This method provides an effective approach for the dosimetry of CBCT scanning in the stationary‐table modes, and is useful for perfusion and interventional CT.
Strength of stick-slip and creeping subduction megathrusts from heat flow observations
Authors: Gao Xiang , Wang Kelin
Published: August 2014

Strong yet creeping megathrust faults

Powerful faults in subduction zones, called “megathrust faults,” produce the largest earthquakes on Earth. Gao and Wang use heat flow data to show that when the faults subduct jagged sea floor, they generate tamer earthquakes than do faults that subduct smooth sea floor. The rugged sea floor brings irregularities into the fault that cause it to deform slowly over time, which results in a comparatively higher fault strength and lower seismicity. The finding has a direct impact on assessing regional earthquake and tsunami hazards.

Science
, this issue p.
1038
Using ecological thresholds to evaluate the costs and benefits of set-asides in a biodiversity hotspot
Authors: Banks-Leite Cristina , Pardini Renata , Tambosi Leandro R. , Pearse William D. , Bueno Adriana A. , Bruscagin Roberta T. , Condez Thais H. , Dixo Marianna , Igari Alexandre T. , Martensen Alexandre C. , Metzger Jean Paul
Published: August 2014

Cost-effective conservation on private land

How affordable is biodiversity conservation in a fragmented landscape? Banks-Leite
et al.
asked this question for the biodiversity hotspot of the Brazilian Atlantic Forest. An annual investment of <10% of Brazil's agricultural subsidies could support effective ecological restoration on private lands. This would increase biodiversity in set-aside land to the same level observed in protected areas. The cost-effectiveness of this scheme suggests a path forward for conservation strategies in other similarly mixed landscapes, too.

Science
, this issue p.
1041
Generation of compartmentalized pressure by a nuclear piston governs cell motility in a 3D matrix
Authors: Petrie Ryan J. , Koo Hyun , Yamada Kenneth M.
Published: August 2014

Push me, pull you, that's the way to move

Primary cells, derived directly from human tissue, exhibit different behaviors in shape and signaling within three-dimensional (3D) or 2D spaces. When the pressure within the cell increases, cells display limb-like bumps, which they use to move through their 3D environment. Petrie
et al.
now show that when the complex of actin and myosin contracts, it controls the pressure within cells and therefore the shape of those protruding structures (see the Perspective by DeSimone and Horwitz). The authors measured internal pressures in migrating mammalian cells. In the 3D matrix, those cells have higher pressure that differs between the front and back of the cell, which creates a piston effect.

Science
, this issue p.
1062
; see also p.
1002
One good cosmic measure
Authors: Girardi Léo
Published: August 2014

Radio-wave interferometry provides an accurate measurement of cosmic distances

[Also see Report by

Melis
et al.

]
Many modes of motility
Authors: DeSimone Douglas W. , Horwitz A. Rick
Published: August 2014

Cells use a piston-driven mechanism, among others, to migrate

[Also see Report by

Petrie
et al.

]
Rekindled HIV infection
Authors: Siliciano Janet D. , Siliciano Robert F.
Published: August 2014

What does the “Mississippi baby” tell us about curing HIV-1 infection?
Invasive Mycosis Due to Species of Blastobotrys in Immunocompromised Patients with Reduced Susceptibility to Antifungals
Authors: Kumar Anil , Babu Rachana , Bijulal Swapna , Abraham Mohan , Sasidharan P. , Kathuria Shallu , Sharma Cheshta , Meis Jacques F. , Chowdhary Anuradha
Published: August 2014

Cases of invasive mycosis due to
Blastobotrys serpentis
and
B. proliferans
identified by sequencing in a preterm patient and a rhabdomyosarcoma patient, respectively, are reported. Both species revealed elevated fluconazole and echinocandin MICs by the CLSI broth microdilution method. Additionally,
B. serpentis
exhibited high amphotericin B MICs, thus posing serious therapeutic challenges.
Rapid Sequencing of the Mycobacterium tuberculosis
pncA
Gene for Detection of Pyrazinamide Susceptibility
Authors: Streicher Elizabeth M. , Maharaj Kashmeel , York Talita , Van Heerden Carel , Barnard Marinus , Diacon Andreas , Mendel Carl M. , Bosman Marlein E. , Hepple Juli A. , Pym Alexander S. , Warren Robin M. , van Helden Paul D.
Published: August 2014

We developed a pyrazinamidase gene DNA-sequencing method to rapidly identify pyrazinamide resistance-causing mutations in GenoLyse-treated, smear-positive sputum specimens. The sensitivity and specificity were 90.9 and 100%, respectively, compared to those of MGIT drug susceptibility testing, after the exclusion of synonymous mutations and nonsynonymous mutations previously associated with susceptibility to pyrazinamide.
Fluorescent Tagging and Cellular Distribution of the Kaposi's Sarcoma-Associated Herpesvirus ORF45 Tegument Protein
Authors: Bergson Shir , Kalt Inna , Itzhak Inbal , Brulois Kevin F. , Jung Jae U. , Sarid Ronit
Published: August 2014

Kaposi's sarcoma-associated herpesvirus (KSHV), also known as human herpesvirus 8 (HHV-8), is a cancer-related human virus, classified as a member of the
Gammaherpesvirinae
subfamily. We report here the construction of a dual fluorescent-tagged KSHV genome (BAC16-mCherry-ORF45), which constitutively expresses green fluorescent protein (GFP) and contains the tegument multifunctional ORF45 protein as a fusion protein with monomeric Cherry fluorescent protein (mCherry). We confirmed that this virus is properly expressed and correctly replicates and that the mCherry-ORF45 protein is incorporated into the virions. Using this labeled virus, we describe the dynamics of mCherry-ORF45 expression and localization in newly infected cells as well as in latently infected cells undergoing lytic induction and show that mCherry can be used to monitor cells undergoing the lytic viral cycle. This virus is likely to enable future studies monitoring the dynamics of viral trafficking and tegumentation during viral ingress and egress.

IMPORTANCE
The present study describes the construction and characterization of a new recombinant KSHV genome BAC16 clone which expresses mCherry-tagged ORF45. This virus enables the tracking of cells undergoing lytic infection and can be used to address issues related to the trafficking and maturation pathways of KSHV virions.
Possible Footprints of APOBEC3F and/or Other APOBEC3 Deaminases, but Not APOBEC3G, on HIV-1 from Patients with Acute/Early and Chronic Infections
Authors: Armitage Andrew E. , Deforche Koen , Welch John J. , Van Laethem Kristel , Camacho Ricardo , Rambaut Andrew , Iversen Astrid K. N.
Published: August 2014

Members of the apolipoprotein B mRNA-editing enzyme-catalytic polypeptide-like-3 (APOBEC3) innate cellular cytidine deaminase family, particularly APOBEC3F and APOBEC3G, can cause extensive and lethal G-to-A mutations in HIV-1 plus-strand DNA (termed hypermutation). It is unclear if APOBEC3-induced mutations
in vivo
are always lethal or can occur at sublethal levels that increase HIV-1 diversification and viral adaptation to the host. The viral accessory protein Vif counteracts APOBEC3 activity by binding to APOBEC3 and promoting proteasome degradation; however, the efficiency of this interaction varies, since a range of hypermutation frequencies are observed in HIV-1 patient DNA. Therefore, we examined “footprints” of APOBEC3G and APOBEC3F activity in longitudinal HIV-1 RNA
pol
sequences from approximately 3,000 chronically infected patients by determining whether G-to-A mutations occurred in motifs that were favored or disfavored by these deaminases. G-to-A mutations were more frequent in APOBEC3G-disfavored than in APOBEC3G-favored contexts. In contrast, mutations in APOBEC3F-disfavored contexts were relatively rare, whereas mutations in contexts favoring APOBEC3F (and possibly other deaminases) occurred 16% more often than average G-to-A mutations. These results were supported by analyses of >500 HIV-1
env
sequences from acute/early infection.

IMPORTANCE
Collectively, our results suggest that APOBEC3G-induced mutagenesis is lethal to HIV-1, whereas mutagenesis caused by APOBEC3F and/or other deaminases may result in sublethal mutations that might facilitate viral diversification. Therefore, Vif-specific cytotoxic T lymphocyte (CTL) responses and drugs that manipulate the interplay between Vif and APOBEC3 may have beneficial or detrimental clinical effects depending on how they affect the binding of Vif to various members of the APOBEC3 family.
Lack of Interleukin-10-Mediated Anti-Inflammatory Signals and Upregulated Interferon Gamma Production Are Linked to Increased Intestinal Epithelial Cell Apoptosis in Pathogenic Simian Immunodeficiency Virus Infection
Authors: Pan Diganta , Kenway-Lynch Carys S. , Lala Wendy , Veazey Ronald S. , Lackner Andrew A. , Das Arpita , Pahar Bapi
Published: August 2014

Interleukin-10 (IL-10) is an immunomodulatory cytokine that is important for maintenance of epithelial cell (EC) survival and anti-inflammatory responses (AIR). The majority of HIV infections occur through the mucosal route despite mucosal epithelium acting as a barrier to human immunodeficiency virus (HIV). Therefore, understanding the role of IL-10 in maintenance of intestinal homeostasis during HIV infection is of interest for better characterization of the pathogenesis of HIV-mediated enteropathy. We demonstrated here changes in mucosal IL-10 signaling during simian immunodeficiency virus (SIV) infection in rhesus macaques. Disruption of the epithelial barrier was manifested by EC apoptosis and loss of the tight-junction protein ZO-1. Multiple cell types, including a limited number of ECs, produced IL-10. SIV infection resulted in increased levels of IL-10; however, this was associated with increased production of mucosal gamma interferon (IFN-γ) and tumor necrosis factor alpha (TNF-α), suggesting that IL-10 was not able to regulate AIR. This observation was supported by the downregulation of STAT3, which is necessary to inhibit production of IFN-γ and TNF-α, and the upregulation of SOCS1 and SOCS3, which are important regulatory molecules in the IL-10-mediated AIR. We also observed internalization of the IL-10 receptor (IL-10R) in mucosal lymphocytes, which could limit cellular availability of IL-10 for signaling and contribute to the loss of a functional AIR. Collectively, these findings demonstrate that internalization of IL-10R with the resultant impact on IL-10 signaling and dysregulation of the IL-10-mediated AIR might play a crucial role in EC damage and subsequent SIV/HIV pathogenesis.

IMPORTANCE
Interleukin-10 (IL-10), an important immunomodulatory cytokine plays a key role to control inflammatory function and homeostasis of the gastrointestinal mucosal immune system. Despite recent advancements in the study of IL-10 and its role in HIV infection, the role of mucosal IL-10 in SIV/HIV infection in inducing enteropathy is not well understood. We demonstrated changes in mucosal IL-10 signaling during SIV infection in rhesus macaques. Disruption of the intestinal epithelial barrier was evident along with the increased levels of mucosal IL-10 production. Increased production of mucosal IFN-γ and TNF-α during SIV infection suggested that the increased level of mucosal IL-10 was not able to regulate anti-inflammatory responses. Our findings demonstrate that internalization of IL-10R with the resultant impact on IL-10 signaling and dysregulation of the IL-10-mediated anti-inflammatory responses might play a crucial role in epithelial cell damage and subsequent SIV/HIV pathogenesis.
Emergence of Individual HIV-Specific CD8 T Cell Responses during Primary HIV-1 Infection Can Determine Long-Term Disease Outcome
Authors: Streeck Hendrik , Lu Richard , Beckwith Noor , Milazzo Mark , Liu Michelle , Routy Jean-Pierre , Little Susan , Jessen Heiko , Kelleher Anthony D. , Hecht Frederick , Sekaly Rafick-Pierre , Alter Galit , Heckerman David , Carrington Mary , Rosenberg Eric S. , Altfeld Marcus
Published: August 2014

Events during primary HIV-1 infection have been shown to be critical for the subsequent rate of disease progression. Early control of viral replication, resolution of clinical symptoms and development of a viral set point have been associated with the emergence of HIV-specific CD8 T cell responses. Here we assessed which particular HIV-specific CD8 T cell responses contribute to long-term control of HIV-1. A total of 620 individuals with primary HIV-1 infection were screened by gamma interferon (IFN-γ) enzyme-linked immunospot (ELISPOT) assay for HLA class I-restricted, epitope-specific CD8 T cell responses using optimally defined epitopes approximately 2 months after initial presentation. The cohort was predominantly male (97%) and Caucasian (83%) (Fiebig stages II/III [
n
= 157], IV [
n
= 64], V [
n
= 286], and VI [
n
= 88] and Fiebig stage not determined [
n
= 25]). Longitudinal viral loads, CD4 count, and time to ART were collected for all patients. We observed strong associations between viral load at baseline (initial viremia) and the established early viral set points (
P
< 0.0001). Both were significantly associated with HLA class I genotypes (
P
= 0.0009). While neither the breadth nor the magnitude of HIV-specific CD8 T cell responses showed an influence on the early viral set point, a broader HIV-specific CD8 T cell response targeting epitopes within HIV-1 Gag during primary HIV-1 infection was associated with slower disease progression. Moreover, the induction of certain HIV-specific CD8 T cell responses—but not others—significantly influenced the time to ART initiation. Individual epitope-specific CD8 T cell responses contribute significantly to HIV-1 disease control, demonstrating that the specificity of the initial HIV-specific CD8 T cell response rather than the restricting HLA class I molecule alone is a critical determinant of antiviral function.

IMPORTANCE
Understanding which factors are involved in the control of HIV-1 infection is critical for the design of therapeutic strategies for patients living with HIV/AIDS. Here, using a cohort of over 600 individuals with acute and early HIV-1 infection, we assessed in unprecedented detail the individual contribution of epitope-specific CD8 T cell responses directed against HIV-1 to control of viremia and their impact on the overall course of disease progression.
Acupuncture Decreases Matrix Metalloproteinase-2 Activity in Patients with Migraine
Authors: Cayir Yasemin , Ozdemir Gokhan , Celik Mine , Aksoy Hulya , Akturk Zekeriya , Laloglu Esra , Akcay Fatih
Published: August 2014

Objective

To evaluate the effect of acupuncture on the serum matrix metalloproteinase-2 (MMP-2) level and activity in patients with migraine.

Methods

After baseline testing, eligible patients with migraine according to the criteria of the International Headache Society who volunteered to join the study were included (n=27). The patients received 10 sessions of acupuncture treatment. The points selected were bilateral ST8, ST44, LI4, LI11, LIV3, SP6, GB1, GB14, GB20, GV14, GV20, Yintang, Taiyang and ear Shenmen. Pain was measured using a visual analogue scale (VAS). Short form-36 (SF-36) was used to determine their quality of life. Blood samples were taken before treatment and after the first and last sessions of acupuncture for measurement of MMP-2 concentration and activity.

Results

The mean VAS was 85.5±16.6 before acupuncture and was significantly decreased to 39.8±20.6 after 10 sessions of acupuncture (p<0.0001). There was a significant increase in all SF-36 scores after acupuncture compared with values before treatment (p<0.0001). No significant differences were found in MMP-2 concentrations before treatment and after the first and last sessions (p>0.05). However, there were significant changes in MMP-2 activity (p<0.0001).

Conclusions

The results of this study showed a clinically relevant decrease in MMP-2 activity in patients with migraine treated with acupuncture. The mechanism underlying the effect of acupuncture in alleviating pain may be associated with a decrease in MMP-2 activity.
Prevalence, determinants and impact of unawareness about the health consequences of tobacco use among 17 929 school personnel in 29 African countries
Authors: Agaku Israel T , Filippidis Filippos T
Published: August 2014

Objectives

To assess prevalence, determinants and impact of unawareness about the health consequences of tobacco use among school personnel in Africa.

Design

Cross-sectional surveys.

Setting

Twenty-nine African countries.

Participants

Representative samples of school personnel from 29 African countries (n=17 929), using data from the 2006–2011 Global School Personnel Surveys.

Outcome

We assessed if school personnel were aware of the following five facts about tobacco use: (1) tobacco use is addictive; (2) secondhand smoke exposure is harmful; (3) smoking causes lung cancer; (4) smoking causes heart disease and (5) smoking does not cause malaria. Using multivariate logistic regression, we measured the impact of unawareness of the health consequences of tobacco use on behaviour and attitudes towards tobacco control.

Results

A median of 62.6% of school personnel were unaware of at least one health consequence of tobacco use. School personnel in countries with mandatory cigarette health warning labels had lower odds of being unaware of any health consequence of tobacco use than countries where health warning labels were not mandatory (adjusted OR [aOR]=0.51; 95% CI 0.37 to 0.71). A significant dose–response relationship was seen between being ignorant of 1; 2; or ≥3 tobacco use health consequences respectively (compared with not being ignorant of any), and the odds of the following outcomes: non-support of bans on tobacco industry sponsorship of school or extracurricular activities (aOR=1.47; 1.91; and 2.98); non-support of bans on all tobacco advertisements (aOR=1.24; 1.78; and 2.68) and non-support of policies prohibiting tobacco use by school personnel on campus (aOR=1.79; 4.45; and 4.56).

Conclusions

Unawareness of the health consequences of tobacco use was associated with poor support for tobacco control policies. Intensified efforts are needed in African countries to warn about the dangers of tobacco use.
Do the eyes have it? Performance of molecular detection of tuberculosis on fresh and paraffin embedded tissues, including those with no visible tissue
Authors: McKew Genevieve L , Dubedat Sally M , Chan Raymond C
Published: August 2014

Background

Little has been published on the performance of tuberculosis PCR with respect to the quality of tissue specimens. Laboratories often receive liquid samples from fine-needle aspirates with no visible tissue for testing. The sensitivity of tuberculosis (TB) PCR on these specimens is unknown.

Methods

TB PCR was compared to culture or a combination of clinical and histopathological evidence of tuberculosis; a separate analysis excluded patients with current or previous treatment.

Results

Sixty-five patients had 81 positive samples; 69 by PCR and 43 by culture. Excluding those on treatment, 51 of 57 (89%) were PCR positive versus 43 of 61 (70%) by culture. 44 samples had ‘no visible tissue’ noted. Five were PCR positive; only one was culture positive. At least two samples were falsely negative.

Conclusions

Sensitivity of TB PCR is superior to culture on tissue. Five of seven TB cases with no visible tissue were PCR positive. The quality of the specimen deserves comment, as the two (5%) known false negatives are of concern.
Steroid‐responsive idiopathic interstitial lung disease in two dogs
Authors: Koster Liza , Kirberger Robert
Published: August 2014

Two dogs had a history of persistent pyrexia, reduced exercise tolerance, inappetence and coughing and failed to respond to repeated courses of antibiotics. Clinical examination detected adventitious lung sounds, pyrexia and submandibular lymphadenopathy. Haematology revealed an inflammatory leucogram. Both dogs had radiological abnormalities consistent with a multifocal interstitial lung pattern. CT performed in one dog had characteristic changes of cryptogenic organising pneumonia (COP), an extremely rare idiopathic interstitial lung disease. Findings included several parenchymal bands, multifocal patchy ground‐glass opacities and multifocal subpleural and peribronchial hyperattenuating poorly defined nodular opacities throughout the lungs. Bronchoalveolar lavage revealed a sterile suppurative exudate, excluding eosinophilic bronchopneumopathy. There was rapid resolution of clinical and radiological signs, with corticosteroids and relapse in one dog after discontinuation of steroids supporting the diagnosis of this rare condition. Lung biopsy, which was not performed in either case, is definitive but considered invasive with major complications reported including death.
Development and evaluation of a system to assess antimicrobial drug use in farm animals: results of an Austrian study
Authors: Ferner C. , Obritzhauser W. , Fuchs K. , Schmerold I.
Published: August 2014

The objective of this study was to develop and evaluate a feasible system for the collection of antimicrobial consumption data in farm animals in Austria. An electronic registry of all antibacterial pharmaceuticals approved in Austria for use in farm animals was created, listing product name, marketing authorisation number, active ingredient, package unit, strength, target species (cattle, swine, poultry), route of administration and indication, and allocating the corresponding code of the World Health Organization (WHO) Anatomical Therapeutic Chemical classification system for veterinary medicines to each substance (ATCvet‐code). Different units (absolute quantities, animal daily dose, assumed daily product dose) enabled computation of the amounts of antimicrobials as pure substance, the constituents of a veterinary medicinal product, or the number of administrations. Two data collection systems were evaluated: (1) data transfer from the management software of veterinary practices or the Austrian Poultry Health Service; and (2) on‐site data collection by manual data input from prescription records into an electronic registry. A total of 14,267 data sets provided by 18 practices were documented during the period January 2008 to March 2010. The total weight of active substances reported amounted to more than 5.4 tonnes for all species studied. The systems proved suitable for routine data acquisition and were considered in a recent national regulation on the surveillance of sale and consumption of veterinary antimicrobial substances.
Kardar–Parisi–Zhang universality class of a discrete erosion model
Authors: Nath Palash , Mandal Pradipta Kumar , Jana Debnarayan
Published: August 2014

We investigate a novel (d + 1)-dimensional discrete erosion model for d = 1, 2 and 3. The dynamics of the model is controlled by the physically motivated erosion mechanism. The coarse grained nature of this erosion process has been well compared with the Kardar–Parisi–Zhang (KPZ) equation. The kinetic roughening of the discrete model shows the same scaling behavior as that of the KPZ equation in the dimensions d = 1, 2. Moreover, in this present discrete model in (3 + 1)-dimension almost smooth interface has been obtained with vanishingly small roughness exponent, indicating the model belongs to the weak coupling regime of KPZ universality class.
Toward cost-efficient sampling methods
Authors: Luo Peng , Li Yongli , Wu Chong , Zhang Guijie
Published: August 2014

The sampling method has been paid much attention in the field of complex network in general and statistical physics in particular. This paper proposes two new sampling methods based on the idea that a small part of vertices with high node degree could possess the most structure information of a complex network. The two proposed sampling methods are efficient in sampling high degree nodes so that they would be useful even if the sampling rate is low, which means cost-efficient. The first new sampling method is developed on the basis of the widely used stratified random sampling (SRS) method and the second one improves the famous snowball sampling (SBS) method. In order to demonstrate the validity and accuracy of two new sampling methods, we compare them with the existing sampling methods in three commonly used simulation networks that are scale-free network, random network, small-world network, and also in two real networks. The experimental results illustrate that the two proposed sampling methods perform much better than the existing sampling methods in terms of achieving the true network structure characteristics reflected by clustering coefficient, Bonacich centrality and average path length, especially when the sampling rate is low.
Chaotic burst synchronization in a two-small-world-layer neuronal network
Authors: Zheng Yanhong , Wang Haixia
Published: August 2014

Chaotic burst synchronization in a two-small-world-layer neuronal network is studied in this paper. For a neuronal network coupled by two single-small-world-layer networks with link probability differences between layers, the two-layer network can achieve synchrony as the interlayer coupling strength increases. When chaotic layer network is coupled with chaotic-burst-synchronization layer network, the latter is dominant at small interlayer coupling strength, so it can make the layer with the irregular pattern show some regular and also exhibit the same pattern with the other layer. However, when chaotic layer is coupled with firing synchronization layer, the ordered layer is dominated by a disordered one with the interlayer coupling strength increasing. When the interlayer coupling strength is large enough, both networks are chaotic burst synchronization. Therefore, the synchronous states strongly depend on the interlayer coupling strength and the link probability. Moreover, the spatiotemporal pattern synchronization between the networks is robust to small noise.
The LAA project and the consequences on LHC
Authors: Wenninger Horst
Published: August 2014

The International Symposium on "Subnuclear Physics: Past, Present and Future", held at the Pontifical Academy of Sciences from 30 October to 2 November 2011, provided an excellent occasion to highlight the achievements of an important project at CERN: the LAA project.
Beyond relativistic quantum string theory
Authors: 't Hooft Gerard
Published: August 2014

The question "What lies beyond the Quantized String or Superstring Theory?" and the question "What lies beyond Quantum Mechanics itself?" might have one common answer: a discretized, classical version of string theory, which lives on a lattice in Minkowski space. The size a of the meshes on this lattice in Minkowski space is determined by the string slope parameter, α′.
Scanning tunneling spectroscopy of a magnetic adatom on graphene
Authors: Gao Yang , Ding Kai-He
Published: August 2014

We present a theoretic study on scanning tunneling spectroscopy (STS) of a magnetic adatom on graphene. Three typical configurations of adatoms on graphene are considered explicitly: the adatom is on the top of a carbon atom (TC), in a substitutional site (SC), or above the center of the honeycomb hexagon (HC). Based on the nonequilibrium Green's function method, we derive the local density of state (LDOS) for the adatom and the differential conductance through the scanning tunneling microscopy (STM) device. Our results show that in comparison with the cases of the TC and SC, there exists an anomalous broadening of the local adatom energy level in the HC, which pushes the adatom energy to first cross the Fermi level, leading to the appearance of an antiresonance in the LDOS due to the interference between the Kondo resonance and the broadened adatom level. Correspondingly, the bias dependence of the differential conductance in the HC exhibits a more asymmetric sharp Kondo peak pinned to the gate voltage, and its height still remains significantly large compared to that for the other two cases. Additionally, with decreasing the gate voltage, the Kondo peak in the differential conductance gradually decays, and eventually vanishes in the absence of the gate voltage.
Well-posedness of a model equation for neurotransmitter diffusion with reactive boundaries
Authors: Raynaud Xavier , Nordaas Magne , Lehre Knut Petter , Danbolt Niels Christian
Published: August 2014

We consider a diffusion equation with reactive boundary conditions. The equation is a model equation for the diffusion of classical neurotransmitters in the tortuous space between cells in the brain. The equation determines the concentration of neurotransmitters such as glutamate and GABA (gamma-aminobutyrate) and the probability for neurotransmitter molecules to be immobilized by binding to protein molecules (receptors and transporters) at the cell boundary (cell membrane). On a regularized problem, we derive a priori estimates. Then, by a compactness argument, we show the existence of solutions. By exploiting the particular structure of the boundary reaction terms, we are able to prove that the solutions are unique and continuous with respect to initial data.
Asymptotic behaviour of solutions to the stationary Navier–Stokes equations in two-dimensional exterior domains with zero velocity at infinity
Authors: Guillod Julien , Wittwer Peter
Published: August 2014

We investigate analytically and numerically the existence of stationary solutions converging to zero at infinity for the incompressible Navier–Stokes equations in a two-dimensional exterior domain. Physically, this corresponds for example to fixing a propeller by an external force at some point in a two-dimensional fluid filling the plane and to ask if the solution becomes steady with the velocity at infinity equal to zero. To answer this question, we find the asymptotic behaviour for such steady solutions in the case where the net force on the propeller is nonzero. In contrast to the three-dimensional case, where the asymptotic behaviour of the solution to this problem is given by a scale invariant solution, the asymptote in the two-dimensional case is not scale invariant and has a wake. We provide an asymptotic expansion for the velocity field at infinity, which shows that, within a wake of width |x|2/3, the velocity decays like |x|-1/3, whereas outside the wake, it decays like |x|-2/3. We check numerically that this behaviour is accurate at least up to second order and demonstrate how to use this information to significantly improve the numerical simulations. Finally, in order to check the compatibility of the present results with rigorous results for the case of zero net force, we consider a family of boundary conditions on the body which interpolate between the nonzero and the zero net force case.
Semi-Analytic Solution of Multiple Inhomogeneous Inclusions and Cracks in an Infinite Space
Authors: Zhou Kun , Wei Rongbing , Bi Guijun , Wang Xu , Song Bin , Feng Xiqiao
Published: August 2014

This work develops a semi-analytic solution for multiple inhomogeneous inclusions of arbitrary shape and cracks in an isotropic infinite space. The solution is capable of fully taking into account the interactions among any number of inhomogeneous inclusions and cracks which no reported analytic or semi-analytic solution can handle. In the solution development, a novel method combining the equivalent inclusion method (EIM) and the distributed dislocation technique (DDT) is proposed. Each inhomogeneous inclusion is modeled as a homogenous inclusion with initial eigenstrain plus unknown equivalent eigenstrain using the EIM, and each crack of mixed modes I and II is modeled as a distribution of edge climb and glide dislocations with unknown densities. All the unknown equivalent eigenstrains and dislocation densities are solved simultaneously by means of iteration using the conjugate gradient method (CGM). The fast Fourier transform algorithm is also employed to greatly improve computational efficiency. The solution is verified by the finite element method (FEM) and its capability and generality are demonstrated through the study of a few sample cases. This work has potential applications in reliability analysis of heterogeneous materials.
New identities for the Wright and the Mittag-Leffler functions using the Laplace transform
Authors: Ansari Alireza , Sheikhani Amirhossein Refahi
Published: August 2014

In this paper, we state three theorems for the inverse Laplace transform and using these theorems we obtain new integral identities involving the products of the Wright and Mittag-Leffler functions. The relationships of these integral identities with the Stieltjes transform are also given.
The noncommutative neutrix product of $x_{-}^{-s}\ln^mx_{-}$ and $x_{+}^{r}$
Authors: Lin Mongkolsery , Orankitjaroen Somsak , Fisher Brian
Published: August 2014

In distribution theory, the product of two distributions can only be defined under certain conditions. In this paper, by using Fisher's definition, it is proved that if Gm,s(x) denotes the distribution ( ln m+1x-)(s), then the noncommutative neutrix product [Formula: see text] exists and [Formula: see text] for m, s ≥ 1, where [Formula: see text]. Related neutrix products are then deduced.