bluuebunny/crossref_metadata_2025 huggingface dataset:
The Complexity of Approximately Counting Tree Homomorphisms
Authors: Goldberg Leslie Ann , Jerrum Mark
Published: June 2014

We study two computational problems, parameterised by a fixed tree
H
. #HOMSTO(
H
) is the problem of counting homomorphisms from an input graph
G
to
H
. #WHOMSTO(
H
) is the problem of counting weighted homomorphisms to
H
, given an input graph
G
and a weight function for each vertex
v
of
G
. Even though
H
is a tree, these problems turn out to be sufficiently rich to capture all of the known approximation behaviour in #
P
. We give a complete trichotomy for #WHOMSTO(
H
). If
H
is a star, then #WHOMSTO(
H
) is in FP. If
H
is not a star but it does not contain a certain induced subgraph
J
3, then #WHOMSTO(
H
) is equivalent under approximation-preserving (AP) reductions to #BIS, the problem of counting independent sets in a bipartite graph. This problem is complete for the class #RHΠ1 under AP-reductions. Finally, if
H
contains an induced
J
3
, then #WHOMSTO(
H
) is equivalent under AP-reductions to #SAT, the problem of counting satisfying assignments to a CNF Boolean formula. Thus, #WHOMSTO(
H
) is complete for #P under AP-reductions. The results are similar for #HOMSTO(
H
) except that a rich structure emerges if
H
contains an induced
J
3
. We show that there are trees
H
for which #HOMSTO(
H
) is #
SAT
-equivalent (disproving a plausible conjecture of Kelk). However, it is still not known whether #HOMSTO(
H
) is #SAT-hard for every tree
H
which contains an induced
J
3. It turns out that there is an interesting connection between these homomorphism-counting problems and the problem of approximating the partition function of the
ferromagnetic Potts model
. In particular, we show that for a family of graphs
Jq
, parameterised by a positive integer
q
, the problem #HOMSTO(
Jq
) is AP-interreducible with the problem of approximating the partition function of the
q
-state Potts model. It was not previously known that the Potts model had a homomorphism-counting interpretation. We use this connection to obtain some additional upper bounds for the approximation complexity of #HOMSTO(
Jq
).
A Note on the Complexity of Comparing Succinctly Represented Integers, with an Application to Maximum Probability Parsing
Authors: Etessami Kousha , Stewart Alistair , Yannakakis Mihalis
Published: June 2014

The following two decision problems capture the complexity of comparing integers or rationals that are succinctly represented in product-of-exponentials notation, or equivalently, via arithmetic circuits using only multiplication and division gates, and integer inputs.
Input instance:
Four lists of positive integers:

a
1,...,
an
∈N+
n
;
b
1,...,
bn
∈N+
n
;
c
1,...,
cm
∈N+
m
;
d
1, ...,
dm
∈N+
m
;

where each of the integers is represented in binary.

Problem 1 (equality testing):
Decide whether
a
1
b
1
a
2
b
2⋯
anbn
=
c
1
d
1
c
2
d
2⋯
cmdm
.

Problem 2 (inequality testing):
Decide whether
a
1
b
1
a
2
b
2⋯
anbn
≥
c
1
d
1
c
2
d
2⋯
cmdm
.

Problem 1 is easily decidable in polynomial time using a simple iterative algorithm. Problem 2 is much harder. We observe that the complexity of Problem 2 is intimately connected to deep conjectures and results in number theory. In particular, if a refined form of the
ABC conjecture
formulated by Baker in 1998 holds, or if the older
Lang-Waldschmidt conjecture
(formulated in 1978) on linear forms in logarithms holds, then Problem 2 is decidable in P-time (in the standard Turing model of computation). Moreover, it follows from the best available quantitative bounds on linear forms in logarithms, namely, by Baker and Wüstholz [1993] or Matveev [2000], that if
m
and
n
are fixed universal constants then Problem 2 is decidable in P-time (without relying on any conjectures). This latter fact was observed earlier by Shub [1993].

We describe one application: P-time maximum probability parsing for arbitrary stochastic context-free grammars (where
ε
-rules are allowed).
Weighted Triangulations for Geometry Processing
Authors: Goes Fernando de , Memari Pooran , Mullen Patrick , Desbrun Mathieu
Published: June 2014

In this article we investigate the use of weighted triangulations as discrete, augmented approximations of surfaces for digital geometry processing. By incorporating a scalar weight per mesh vertex, we introduce a new notion of discrete metric that defines an orthogonal dual structure for arbitrary triangle meshes and thus extends weighted Delaunay triangulations to surface meshes. We also present alternative characterizations of this primal-dual structure (through combinations of angles, areas, and lengths) and, in the process, uncover closed-form expressions of mesh energies that were previously known in implicit form only. Finally, we demonstrate how weighted triangulations provide a faster and more robust approach to a series of geometry processing applications, including the generation of well-centered meshes, self-supporting surfaces, and sphere packing.
Fabrication of a Miniature Zinc Aluminum Oxide Nanowire Array Gas Sensor and Application for Environmental Monitoring
Authors: Kuo Chin-Guo , Huang Chi-Wu , Chen Jung-Hsuan , Liu Yueh-Han
Published: June 2014

A miniature n-type semiconductor gas sensor was fabricated successfully using zinc aluminum oxide nanowire array and applied to sense oxygen. The present study provided a novel method to produce zinc aluminum alloy nanowire 80 nm in diameter by the vacuum die casting technique and then obtain zinc aluminum oxide nanowire array using the thermal oxidation technique. The gas sensing properties were evaluated through the change of the sensitivity. The factors influencing the sensitivity of the gas sensor, such as the alloy composition, operating temperature, and oxygen concentration, were investigated further. Experimental results indicated that the maximum sensitivity could be acquired when the weight percentage of aluminum was 5% in zinc aluminum alloy at the operating temperature of200°C.
Control of Limit Cycle Oscillation in a Three Degrees of Freedom Airfoil Section Using Fuzzy Takagi-Sugeno Modeling
Authors: Bueno Douglas Domingues , Sandoval Góes Luiz Carlos , Gonçalves Paulo José Paupitz
Published: June 2014

This work presents a strategy to control nonlinear responses of aeroelastic systems with control surface freeplay. The proposed methodology is developed for the three degrees of freedom typical section airfoil considering aerodynamic forces from Theodorsen’s theory. The mathematical model is written in the state space representation using rational function approximation to write the aerodynamic forces in time domain. The control system is designed using the fuzzy Takagi-Sugeno modeling to compute a feedback control gain. It useds Lyapunov’s stability function and linear matrix inequalities (LMIs) to solve a convex optimization problem. Time simulations with different initial conditions are performed using a modified Runge-Kutta algorithm to compare the system with and without control forces. It is shown that this approach can compute linear control gain able to stabilize aeroelastic systems with discontinuous nonlinearities.
Packing Constant in Orlicz Sequence Spaces Equipped with the p-Amemiya Norm
Authors: He Xin , Yu Jijie , Cui Yunan , Huo Xin
Published: June 2014

The problem of packing spheres in Orlicz sequence spacelΦ,pequipped with the p-Amemiya norm is studied, and a geometric characteristic about the reflexivity oflΦ,pis obtained, which contains the relevant work aboutlp  (p>1)and classical Orlicz spaceslΦdiscussed by Rankin, Burlak, and Cleaver. Moreover the packing constant as well as Kottman constant in this kind of spaces is calculated.
Characterization of the Organic Thin Film Solar Cells with Active Layers of PTB7/PC71BM Prepared by Using Solvent Mixtures with Different Additives
Authors: Ito Masakazu , Palanisamy Kumar , Kumar Abhirami , Murugesan Vijay Srinivasan , Shin Paik-Kyun , Tsuda Norio , Yamada Jun , Ochiai Shizuyasu
Published: June 2014

Organic thin film solar cells (OTFSCs) were fabricated with blended active layers of poly[[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl]] (PTB7)/[6,6]-phenyl-C71-butyric (PC71BM). The performances of active layers are prepared in chlorobenzene (CB) with different additives of 1-chloronaphthalene (CN) and 1,8-Diiodooctane (DIO) by a wet process with spin coating technique. The effects of different solvent additives on photovoltaic parameters such as fill factor, short circuit current density, and power conversion efficiency of active layers are reported. The absorption and surface morphology of the active layers are investigated using UV-visible spectroscopy and atomic force microscopy, respectively. The results indicate that structural and morphological changes were induced by the additives with solvent. The current density-voltage (J-V) characteristics of photovoltaic cells were measured under the illumination of simulated solar light with 100 mW/cm2(AM 1.5 G) by an Oriel 1000 W solar simulator. The OTFSCs of PTB7/PC71BM prepared with organic solvent additives of DIO+CN show more improved PCE of 4.96% by spin coating method.
Background-Suppressed MR Venography of the Brain Using Magnitude Data: A High-Pass Filtering Approach
Authors: Jin Zhaoyang , Xia Ling , Zhang Minming , Du Yiping P.
Published: June 2014

Conventional susceptibility-weighted imaging (SWI) uses both phase and magnitude data for the enhancement of venous vasculature and, thus, is subject to signal loss in regions with severe field inhomogeneity and in the peripheral regions of the brain in the minimum-intensity projection. The purpose of this study is to enhance the visibility of the venous vasculature and reduce the artifacts in the venography by suppressing the background signal in postprocessing. A high-pass filter with an inverted Hamming window or an inverted Fermi window was applied to the Fourier domain of the magnitude images to enhance the visibility of the venous vasculature in the brain after data acquisition. The high-pass filtering approach has the advantages of enhancing the visibility of small veins, diminishing the off-resonance artifact, reducing signal loss in the peripheral regions of the brain in projection, and nearly completely suppressing the background signal. The proposed postprocessing technique is effective for the visualization of small venous vasculature using the magnitude data alone.
The Complexity Uncertain Analysis about Three Differences Old and New Product Pricing Oligarch Retailers Closed-Loop Supply Chain
Authors: Ma Junhai , Chen Bin
Published: June 2014

This paper studied some realistic recycle fields at present in China, such as some daily machinery and equipment, electronic products, and plastic products. Under such circumstance, three oligarch retailers are a common situation. In this paper, we model and analyze the game of three oligarch retailers in a closed-loop supply chain. The stability of the Nash equilibrium, the bifurcation and chaos phenomenon of the recycling price and new product quantity when retailers change its adjustment speed, the profit trends of the three retailers, and the power spectrum are studied. At last, we used the parameter adjustment and the variable state feedback control strategy for chaos control, and the chaos of the system is delayed effectively. For closed-loop supply chain research, the conclusions of the numerical simulation in this paper not only have realistic guiding significance, but also have theoretical reference value.
Asymmetric Dimethylarginine and Progression of Chronic Kidney Disease - a One-Year Follow-Up Study
Authors: Eiselt Jaromír , Rajdl Daniel , Racek Jaroslav , Vostrý Michal , Rulcová Kamila , Wirth Jan
Published: June 2014

Background/Aims: Asymmetric dimethylarginine (ADMA) is a prognostic factor in patients with chronic kidney disease (CKD). However, the relationships among factors influencing the metabolism of ADMA and the CKD progression are not fully understood. Methods: Serum ADMA, and variables related to the metabolism of ADMA were measured in 181 non-dialysis patients (CKD stages 3-5) and in 46 controls. Patients were assessed at baseline, and 6 and 12 months after the initiation of the study. Results: Patients had increased baseline ADMA, advanced glycation end products (AGE), and advanced oxidation protein products (AOPP) compared with controls (P<0.001). In a total of 164 patients who completed a one-year study, the estimated GFR (eGFR) declined from 23.5 (17.7-36) mL/min/1.73m2 to 21 (14.7-31.5) (P=0.018), AGE rose from 1.58 (1.38-1.90) μmol/L to 1.76 (1.52-2.21) (P<0.001), while ADMA, AOPP, tubular function, and proteinuria remained stable. In a multiple regression model (adjusted R2 = 0.49, P<0.0001), the interaction of relatively higher baseline eGFR, i.e. > 25 mL/min/1.73m2, with higher ADMA (P=0.02) and higher AOPP (P=0.04) predicted the severest decrease in eGFR per year. Other predictors of progression were higher baseline AGE (P<0.001), proteinuria (P=0.003), hypertension (P=0.01), and higher baseline eGFR (P=0.03). Conclusion: Elevated ADMA and markers of oxidative stress were strong predictors of progression in patients with eGFR between 25-40 mL/min/1.73m2 , i.e. at the borderline of CKD stages 3-4.
Can Intermittent Theta Burst Stimulation as Add-On to Psychotherapy Improve Nicotine Abstinence? Results from a Pilot Study
Authors: Dieler Alica C. , Dresler Thomas , Joachim Kathrin , Deckert Jürgen , Herrmann Martin J. , Fallgatter Andreas J.
Published: June 2014

Smoking is among the leading causes of mortality worldwide. Discontinuing smoking can increase life expectancy to the presmoking level. Unaided attempts are often ineffective, strengthening the necessity of cognitive-behavioral therapy (CBT), nicotine replacement or pharmacotherapy. Still, relapse rates are high. Recently, a modulation of nicotine craving, which predicts relapse, through transcranial magnetic stimulation to the prefrontal cortex was shown. In a pilot study, we investigated whether 4 sessions of intermittent theta burst stimulation (iTBS) as add-on treatment to CBT reduces nicotine craving and improves long-term abstinence (at 3, 6 and 12 months). Smokers were randomly assigned to a treatment (n = 38) or a sham group (n = 36). Although we did not find reduced craving, we could show higher abstinence rates in the treatment group at 3 months. At 6 and 12 months abstinence rates did not differ significantly. Results at 12 months, however, have to be interpreted cautiously due to significant differences in the dropout rates between the two groups at this time point. We provide first evidence for a beneficial effect of additional iTBS on intermediate nicotine abstinence; however, the low number of iTBS sessions might have prevented longer effects. More lasting effects might be achieved by iTBS maintenance sessions in analogy to the treatment of depression.
The Effects of Aging on Changes in Regional Cerebral Blood Flow in Schizophrenia
Authors: Kawakami Kazunori , Wake Rei , Miyaoka Tsuyoshi , Furuya Motohide , Liaury Kristian , Horiguchi Jun
Published: June 2014

Aims: Although there have been no conclusive pathophysiological findings in support of the degeneration theory in the etiology of schizophrenia to date, results of our neuroimaging studies suggest functional changes in the brains of schizophrenics. We evaluated age-related changes of brain perfusion in medicated patients with schizophrenia. Method: In this study, we evaluated age-related changes in brain perfusion in medicated schizophrenia patients (n = 44) and control subjects (n = 37) undergoing 99mTc-ethyl cysteinate dimer single-photon emission computed tomography. Result: Although the regional cerebral blood flow (rCBF) was found to be reduced in bilateral frontal lobes by analysis with age in the patients with schizophrenia, significant differences compared to controls in age effects on perfusion were found in the patients with schizophrenia in bilateral temporal lobes. Moreover, in multiple regression analysis including age, total time of treatment and overall neuroleptic dose, rCBF was found to be reduced in bilateral frontal and parietal lobes. As a result, cerebral perfusion in temporal lobes with schizophrenia might be related to age rather than medication. Conclusion: In this study, the patients with schizophrenia appeared to have significant bilateral temporal hypoperfusion related to age compared with controls. And bilateral temporal rCBF is decreased in patients with schizophrenia and even more in older schizophrenia patients. These changes might be consistent with degenerative changes observed in patients with schizophrenia and be a promising method for the efficient development of a treatment strategy by measuring temporal perfusion in patients with schizophrenia.
Stimulant Use and Its Impact on Growth in Children Receiving Growth Hormone Therapy: An Analysis of the KIGS® International Growth Database
Authors: Miller Bradley S. , Aydin Ferah , Lundgren Frida , Lindberg Anders , Geffner Mitchell E.
Published: June 2014

Background: Children receiving stimulants for attention deficit hyperactivity disorder (ADHD) frequently present to pediatric endocrinology clinics for evaluation and treatment of growth disorders. The worldwide prevalence of stimulant use in children with ADHD also receiving recombinant human growth hormone (rhGH) and the impact on response to rhGH are unknown. Methods: Data on children enrolled in the KIGS® (Pfizer International Growth Study) registry were evaluated for the associated diagnosis of ADHD prior to initiation of Genotropin® rhGH. Concomitant stimulant medications and auxological information were captured. Response to rhGH was evaluated using established growth prediction models. Results: The prevalence of ADHD in KIGS was 2.3% (1,748/75,251), with stimulants used in 1.8% (1,326/75,251). Children with idiopathic growth hormone deficiency (IGHD) who received stimulants grew significantly less (1.1 cm) in the first year of rhGH therapy than expected for rhGH-treated non-ADHD IGHD children. After one year of rhGH, idiopathic short stature (ISS) children with ADHD were significantly shorter [0.74 cm (with stimulants) and 0.69 cm (without stimulants)] than non-ADHD ISS children. Conclusions: We demonstrated an impaired response to rhGH in IGHD and ISS children with ADHD. Our findings suggest that the ADHD phenotype, alone or in conjunction with stimulant therapy, may impair the short-term growth response to rhGH.
TP53 Mutations in Advanced Colorectal Cancer: The Dark Side of the Moon
Authors: Pietrantonio Filippo , Biondani Pamela , Perrone Federica , Di Bartolomeo Maria , Pacifici Monica , Milione Massimo , Melotti Flavia , Maggi Claudia , Montemurro Gabriella , Bossi Ilaria , Mariani Luigi , de Braud Filippo
Published: June 2014

Background: Evidence for TP53 mutations as biomarker in colorectal cancer (CRC) is conflicting. Methods: We assessed TP53 mutations in 51 patients with advanced CRC enrolled into a phase II, randomised trial of first-line tegafur-uracil (UFT)/leucovorin (LV) plus irinotecan (n = 23) versus UFT/LV plus oxaliplatin (n = 28). Results: Non-functional TP53 mutations were found in 35% of patients. The response rate was not significantly different according to TP53 status. Progression-free and overall survival were longer in patients with TP53 mutations compared to those with wild-type TP53 (9 vs. 6.5 months, p = 0.0504, and 39.2 vs. 19.6 months, p = 0.0055, respectively). On multivariable analysis, TP53 mutation was independently associated with a decreased risk of death (hazard ratio 0.329, 95% CI 0.159-0.679; p = 0.0026). Treatment arm did not interact with TP53 in influencing outcomes. Conclusion:TP53 was not predictive of benefit from first-line irinotecan- or oxaliplatin-based chemotherapy. TP53 mutations may possibly be associated with a more indolent course of CRC after the diagnosis of metastatic disease.
Diet-Induced and Age-Related Changes in the Quadriceps Muscle: MRI and MRS in a Rat Model of Sarcopenia
Authors: Fellner Claudia , Schick Fritz , Kob Robert , Hechtl Christine , Vorbuchner Marianne , Büttner Roland , Hamer Okka W. , Sieber Cornel C. , Stroszczynski Christian , Bollheimer L. Cornelius
Published: June 2014

Background: Knowledge about the molecular pathomechanisms of sarcopenia is still sparse, especially with regard to nutritional risk factors and the subtype of sarcopenic obesity. Objective: The aim of this study was to characterize diet-induced and age-related changes on the quality and quantity of the quadriceps muscle in a rat model of sarcopenia by different magnetic resonance (MR) techniques. Methods: A total of 36 6-month-old male Sprague-Dawley rats were randomly subdivided into 2 groups and received either a high-fat diet (HFD) or a control diet (CD). At the age of 16 months, 15 HFD and 18 CD rats underwent MR at 1.5 T. T1-weighted images as well as T2 relaxation time maps were acquired perpendicular to the long axis of the quadriceps muscles. Maximum cross-sectional area (CSA) of the quadriceps muscle was measured on T1-weighted images, and T2 relaxation times of muscle were assessed in a region without visible intramuscular fat (T2lean muscle) and across the complete CSA (T2muscle). Furthermore, 1H-MR spectroscopy was performed to evaluate the relative lipid content of the quadriceps muscles. These measurements were repeated 5 months later in the surviving 8 HFD and 14 CD rats. Results: HFD rats revealed significantly decreased CSA and CSA per body weight (BW) as well as prolonged T2 relaxation times of muscle. A higher weight gain (upper tertile during the first 6 months of diet in CD rats) resulted in a significant change of T2muscle, but had no relevant impact on CSA. Advancing age up to 21 months led to significantly decreased BW, CSA and CSA/BW, significantly prolonged T2muscle and T2lean muscle and enlarged lipid content in the quadriceps muscle. Conclusions: In an experimental setting a chronically fat-enriched diet was shown to have a relevant and age-associated influence on both muscle quantity and quality. By translational means the employed MR techniques give rise to the possibility of an early detection and noninvasive quantification of sarcopenia in humans, which is highly relevant for the field of geriatrics.
Amniotic Fluid Embolism Induces Uterine Anaphylaxis and Atony following Cervical Laceration
Authors: Tamura Naoaki , Nagai Hisashi , Maeda Hidyuki , Kuroda Ryo-hei , Nakajima Makoto , Igarashi Atsuko , Kanayama Naohiro , Yoshida Ken-ichi
Published: June 2014

Amniotic fluid embolism (AFE) is a rare, high-risk obstetric complication primarily found in the lungs and potentially related to anaphylaxis. Tryptase release from the mast cell reflects anaphylaxis. Case report and findings: A female, aged over 40 years, presented with uterine atony and lethal hemorrhage after induced vaginal labor. Cervical laceration was accompanied by severe hemorrhage. Stromal edema and myometrial swelling were consistent with uterine atony. Alcian blue staining and zinc coproporphyrin immunostaining disclosed AFE, which was more prominent in the uterus than in the lungs. Tryptase immunostaining was diffuse and prominent around the activated mast cells (halos) in the uterus, including the cervix. Similar distribution of findings on the AFE markers, tryptase halos, complement receptor C5aR, and atony in the uterus suggested the causality of AFE to anaphylaxis, complement activation and atony. It is probable that disseminated intravascular coagulation (DIC), induced by AFE, uterine atony and cervical laceration, caused the lethal hemorrhage. It is likely that AFE, in association with cervical laceration, induces uterine anaphylaxis, complement activation, atony, DIC and lethal hemorrhage.
Cumulative Radiation Exposure and Cancer Risk Estimation in Children With Heart Disease
Authors: Johnson Jason N. , Hornik Christoph P. , Li Jennifer S. , Benjamin Daniel K. , Yoshizumi Terry T. , Reiman Robert E. , Frush Donald P. , Hill Kevin D
Published: June 2014

Background—

Children with heart disease are frequently exposed to imaging examinations that use ionizing radiation. Although radiation exposure is potentially carcinogenic, there are limited data on cumulative exposure and the associated cancer risk. We evaluated the cumulative effective dose of radiation from all radiation examinations to estimate the lifetime attributable risk of cancer in children with heart disease.

Methods and Results—

Children ≤6 years of age who had previously undergone 1 of 7 primary surgical procedures for heart disease at a single institution between 2005 and 2010 were eligible for the study. Exposure to radiation-producing examinations was tabulated, and cumulative effective dose was calculated in millisieverts. These data were used to estimate lifetime attributable risk of cancer above baseline using the approach of the Committee on Biological Effects of Ionizing Radiation VII. The cohort included 337 children exposed to 13 932 radiation examinations. Conventional radiographs represented 92% of examinations, whereas cardiac catheterization and computed tomography accounted for 81% of cumulative exposure. Overall median cumulative effective dose was 2.7 mSv (range, 0.1–76.9 mSv), and the associated lifetime attributable risk of cancer was 0.07% (range, 0.001%–6.5%). Median lifetime attributable risk of cancer ranged widely depending on surgical complexity (0.006%–1.6% for the 7 surgical cohorts) and was twice as high in females per unit exposure (0.04% versus 0.02% per 1-mSv effective dose for females versus males, respectively;
P
<0.001).

Conclusions—

Overall radiation exposures in children with heart disease are relatively low; however, select cohorts receive significant exposure. Cancer risk estimation highlights the need to limit radiation dose, particularly for high-exposure modalities.
Serum 25-Hydroxyvitamin D and Orthostatic Hypotension in Old People
Authors: Veronese Nicola , Bolzetta Francesco , De Rui Marina , Zambon Sabina , Corti Maria-Chiara , Musacchio Estella , Baggio Giovannella , Crepaldi Gaetano , Perissinotto Egle , Manzato Enzo , Sergi Giuseppe
Published: June 2014

Interest in the association between serum 25-hydroxyvitamin D (25OHD) and blood pressure has increased because recent research showed a close relationship between them, but there is still little information on the possible association between 25OHD and orthostatic hypotension. The aim of this study was to explore the relationship of 25OHD levels with any presence of orthostatic hypotension in a large group of older people. This study was part of the Progetto Veneto Anziani (Pro.V.A.), an Italian population–based cohort study involving people aged >65 years. In this cross-sectional work, we considered 2640 (1081 men and 1559 women) with a mean age of 73.8±6.8 years. Orthostatic hypotension was defined as a drop of ≤20 mm Hg in systolic or ≤10 mm Hg in diastolic blood pressure <3 minutes of orthostatism. Orthostatic hypotension was identified in 32.2% of the sample. The prevalence of orthostatic hypotension was higher in individuals with 25OHD levels <50 nmol/L, but this trend was not significant (
P
=0.13). Individuals who had orthostatic hypotension had significantly lower 25OHD levels than those who did not (75.0±51.4 versus 82.6±54.0 nmol/L;
P
<0.0001). On logistic regression analysis, the greater likelihood of individuals with lower 25OHD levels having orthostatic hypotension was no longer statistically significant after adjusting for potential confounders (odds ratio, 1.08; 95% confidence interval, 0.77–1.51;
P
=0.67 for people with 25OHD levels ≤25 nmol/L; odds ratio, 1.01; 95% confidence interval, 0.78–1.32;
P
=0.92 for those with 25OHD levels between 25 and 50 nmol/L). In conclusion, vitamin D is not significantly associated with any orthostatic hypotension in older people.
Epigenetic Upregulation of Large-Conductance Ca
2+
-Activated K
+
Channel Expression in Uterine Vascular Adaptation to Pregnancy
Authors: Chen Man , Dasgupta Chiranjib , Xiong Fuxia , Zhang Lubo
Published: June 2014

Our previous study demonstrated that pregnancy increased large-conductance Ca
2+
-activated potassium channel β1 subunit (BKβ1) expression and large-conductance Ca
2+
-activated potassium channel activity in uterine arteries, which were abrogated by chronic hypoxia. The present study tested the hypothesis that promoter methylation/demethylation is a key mechanism in epigenetic reprogramming of BKβ1 expression patterns in uterine arteries. Ovine BKβ1 promoter of 2315 bp spanning from −2211 to +104 of the transcription start site was cloned, and an Sp1
−380
binding site that contains CpG dinucleotide in its core binding sequences was identified. Site-directed deletion of the Sp1 site significantly decreased the BKβ1 promoter activity. Estrogen receptor-α bound to the Sp1 site through tethering to Sp1 and upregulated the expression of BKβ1. The Sp1 binding site at BKβ1 promoter was highly methylated in uterine arteries of nonpregnant sheep, and methylation inhibited transcription factor binding and BKβ1 promoter activity. Pregnancy caused a significant decrease in CpG methylation at the Sp1 binding site and increased Sp1 binding to the BKβ1 promoter and BKβ1 mRNA abundance. Chronic hypoxia during gestation abrogated this pregnancy-induced demethylation and upregulation of BKβ1 expression. The results provide evidence of a novel mechanism of promoter demethylation in pregnancy-induced reprogramming of large-conductance Ca
2+
-activated potassium channel expression and function in uterine arteries and suggest new insights of epigenetic mechanisms linking gestational hypoxia to aberrant uteroplacental circulation and increased risk of preeclampsia.
Subjective Cognitive Failures in Patients With Hypertension Are Related to Cognitive Performance and Cerebral Microbleeds
Authors: Uiterwijk Renske , Huijts Marjolein , Staals Julie , Duits Annelien , Gronenschild Ed , Kroon Abraham A. , de Leeuw Peter W. , van Oostenbrugge Robert J.
Published: June 2014

Previous studies on the relationship between subjective cognitive failures (SCF) and objective cognitive function have shown inconsistent results. In addition, research on the association between SCF and imaging markers of cerebral small vessel disease is limited. We investigated whether SCF in patients with essential hypertension, who are at high risk of cerebral small vessel disease, are associated with objective cognitive function and magnetic resonance imaging manifestations of cerebral small vessel disease. We included 109 patients with hypertension who underwent extensive neuropsychological assessment, including questionnaires measuring SCF and symptoms of anxiety and depression. Brain magnetic resonance imaging was performed to rate the presence of lacunes, cerebral microbleeds, and perivascular spaces, as well as white matter hyperintensities volume. Results showed significant associations between SCF and objectively measured overall cognition (
B
=−0.02; 95% confidence interval=−0.03 to −0.005), memory (
B
=0.02; 95% confidence interval=−0.03 to −0.004), and information processing speed (
B
=−0.02; 95% confidence interval=−0.03 to −0.001) after adjustment for patient characteristics and vascular risk factors. In addition, SCF were associated with the presence of cerebral microbleeds (odds ratio=1.12; 95% confidence interval=1.02–1.23) after adjustment for patient characteristics and vascular risk factors but not with other imaging markers of cerebral small vessel disease. Our study demonstrates that attention for SCF in patients with hypertension is needed because these may point to lower objective cognitive function, which might be as a result of the presence of cerebral microbleeds. Accordingly, this study emphasizes that neuropsychological assessment and brain imaging need to be considered when patients with hypertension report SCF.
Nesting biology of the small carpenter bees Ceratina propinqua and Ceratina simillima (Hymenoptera: Apidae)
Authors: Kumar Yogi Manish , Khan M.S.
Published: June 2014

Bees are considered as the most important group of pollinators for the maintenance of wild flower diversity and the reproduction of agricultural crops. The present study on nesting biology ofCeratinapropinquaandCeratina simillimawas carried out to generate information about nesting shelters and ecological environment of these bees for their conservation and management. Surveys at weekly intervals were conducted from August, 2011 to June, 2012 in the probable nesting sites. The nest making period forC. propinquaandC. simillimaat Pantnagar was the month of May-June. Both species constructed linear nests in the soft pith.C. propinquafemales in dead wood ofSesbania bispinosa(Jacq.) (Fabaceae) and in open end branches ofCaesalpinia pulcherrima(L.) (Fabaceae), whileC. simillimafemales used onlyCaesalpiniaas its nesting shelter. The complete nest ofC. propinquacontained a series of brood cells which were frequently separated by empty cells (the oldest cell below) whileC. simillimanests were observed without empty cells. Cell partitions were made of pith compactly packed together, partitions upper surfaces were irregularly flat and lower surfaces were usually concave in both the species. Brood cells have immature stages along with or without bee bread (provision) and faecal materials. Orientation of prepupae, pupae and preadults ofC. propinquawas downward towards the base of the nesting stem while pupae ofC. simillimaoriented upward towards the entrance of the nest. These findings may help to increase agricultural productivity and conserve natural biological diversity.
Where Do Peacekeepers Go When They Go?
Authors: Townsen Ashly Adam , Reeder Bryce W.
Published: June 2014

Recent developments in the availability of spatial data and the growing trend of spatial analysis in political science has given scholars the ability to account for local-level factors in the study of political violence and conflict management. In this paper, the authors contribute to this growing body of literature by employing geo-coded data to empirically explore a question central to the study of peacekeeping – when peacekeepers are authorized to enter a conflict, where do they go? In other words, what types of violence are peacekeeping forces most concerned with, and what geographic features might prevent or allow for the deployment of peacekeepers? Using the un mission in the Democratic Republic of the Congo, the authors find that peacekeeping forces were less concerned with non-state violence (rebels fighting rebels) and instead focused on government-rebel confrontations and those instances in which government or rebels attacked unarmed civilians. In addition, peacekeepers are shown to cluster around transportation networks, densely populated areas, surface-based resources, and international borders.
Challenges and Prospects of au-un Hybrid Operations
Authors: Bashua Abiodun
Published: June 2014

Hybrid operations between regional organisations and the United Nations is a new paradigm in international peacekeeping. The only such operation so far is the African Union-United Nations Operations in Darfur (unamid). Serving two separate authorizing bodies with different though similar mandates and differing work habits and processes have been a challenge, not only to the two authorising bodies but particularly for the leadership of the hybrid operation. After more than five years of operations, this paper attempts to assess the chances of replication of similar operations in the short-term given the unamid experience.
A GSI-Based Coupled EnSRF–En3DVar Hybrid Data Assimilation System for the Operational Rapid Refresh Model: Tests at a Reduced Resolution
Authors: Pan Yujie , Zhu Kefeng , Xue Ming , Wang Xuguang , Hu Ming , Benjamin Stanley G. , Weygandt Stephen S. , Whitaker Jeffrey S.
Published: June 2014

A coupled ensemble square root filter–three-dimensional ensemble-variational hybrid (EnSRF–En3DVar) data assimilation (DA) system is developed for the operational Rapid Refresh (RAP) forecasting system. The En3DVar hybrid system employs the extended control variable method, and is built on the NCEP operational gridpoint statistical interpolation (GSI) three-dimensional variational data assimilation (3DVar) framework. It is coupled with an EnSRF system for RAP, which provides ensemble perturbations. Recursive filters (RF) are used to localize ensemble covariance in both horizontal and vertical within the En3DVar. The coupled En3DVar hybrid system is evaluated with 3-h cycles over a 9-day period with active convection. All conventional observations used by operational RAP are included. The En3DVar hybrid system is run at ⅓ of the operational RAP horizontal resolution or about 40-km grid spacing, and its performance is compared to parallel GSI 3DVar and EnSRF runs using the same datasets and resolution. Short-term forecasts initialized from the 3-hourly analyses are verified against sounding and surface observations. When using equally weighted static and ensemble background error covariances and 40 ensemble members, the En3DVar hybrid system outperforms the corresponding GSI 3DVar and EnSRF. When the recursive filter coefficients are tuned to achieve a similar height-dependent localization as in the EnSRF, the En3DVar results using pure ensemble covariance are close to EnSRF. Two-way coupling between EnSRF and En3DVar did not produce noticeable improvement over one-way coupling. Downscaled precipitation forecast skill on the 13-km RAP grid from the En3DVar hybrid is better than those from GSI 3DVar analyses.
Regional, Seasonal, and Diurnal Variations of Cloud-to-Ground Lightning with Large Impulse Charge Moment Changes
Authors: Beavis Nick K. , Lang Timothy J. , Rutledge Steven A. , Lyons Walter A. , Cummer Steven A.
Published: June 2014

The use of both total charge moment change (CMC) and impulse charge moment change (iCMC) magnitudes to assess the potential of a cloud-to-ground (CG) lightning stroke to induce a mesospheric sprite has been well described in the literature, particularly on a case study basis. In this climatological study, large iCMC discharges for thresholds of >100 and >300 C km in both positive and negative polarities are analyzed on a seasonal basis. Also presented are local solar time diurnal distributions in eight different regions covering the lower 48 states as well as the adjacent Atlantic Ocean, including the Gulf Stream.

The seasonal maps show the predisposition of large positive iCMCs to dominate across the northern Great Plains, with large negative iCMCs favored in the southeastern United States year-round. During summer, the highest frequency of large positive iCMCs across the upper Midwest aligns closely with the preferred tracks of nocturnal mesoscale convective systems (MCSs). As iCMC values increase above 300 C km, the maximum shifts eastward of the 100 C km maximum in the central plains.

Diurnal distributions in the eight regions support these conclusions, with a nocturnal peak in large iCMC discharges in the northern Great Plains and Great Lakes, an early to midafternoon peak in the Intermountain West and the southeastern United States, and a morning peak in large iCMC discharge activity over the Atlantic Ocean. Large negative iCMCs peak earlier in time than large positive iCMCs, which may be attributed to the growth of large stratiform charge reservoirs following initial convective development.
Integrated Weather Effects on Cycling Shares, Frequencies, and Durations in Rotterdam, the Netherlands
Authors: Böcker Lars , Thorsson Sofia
Published: June 2014

With the increasing societal interest in climate change, health, accessibility, and liveability and subsequent policy aims to promote active transport modes over car usage, many scholars have investigated the relationship between weather and cycling. Existing studies, however, hardly address the effects of weather on cycling durations and often lack assessments of the combined effects of different meteorological variables and potential nonlinearity of these effects. Drawing on travel diary data from a panel study of 945 Greater Rotterdam respondents (the Netherlands), this paper investigates and compares the effects of different meteorological variables, singly as well as combined, on cycling frequencies, cycling durations, and the exchange between cycling and other transport modes. Results show linear negative effects of precipitation sum and wind speed and nonlinear bell-shaped effects of thermal variables on cycling and opposite effects on car usage. Out of three thermal variables investigated, mean radiant temperature (radiant heat exchange between humans and the environment) and physiological equivalent temperature (an index combining the effects of air temperature, mean radiant temperature, air humidity, and wind speed) better explain cycling behavior than just air temperature. Optimum thermal conditions for cycling were found on days with maximum air temperatures around 24°C, mean radiant temperatures around 52°C, and physiological equivalent temperatures around 30°C. Policy and planning implications are highlighted that could reduce cyclists’ exposures to disadvantageous weather conditions such as heat, precipitation, and wind, at present and in a potentially changing climate.
Changes in Family Composition
Authors: Cancian Maria , Haskins Ron
Published: June 2014

This article discusses the consequences of family composition for poverty and income and its implications for policy. Marriage rates are declining, rates of nonmarital births are increasing (both poverty-increasing), while families are smaller, and there are more working mothers (both poverty-decreasing). Marriage remains less likely and nonmarital births more common for blacks than for whites and Hispanics, though even among whites, 36 percent of births were to unmarried mothers by 2011. On the other hand, divergent patterns across education groups are more common: marriage rates have continued to fall, but not for women with college degrees. Men’s earnings have fallen, and, after an increase, women’s have also declined—though less so for those with bachelor’s degrees. The article also discusses policy responses designed to reduce nonmarital childbearing (potentially reducing the number of children and families at high risk of poverty) and to help single-mother families (reducing the risk of poverty faced by such families).
The Family-Go-Round
Authors: Tach Laura , Edin Kathryn , Harvey Hope , Bryan Brielle
Published: June 2014

Men who have children with several partners are often assumed to be “deadbeats” who eschew their responsibilities to their children. Using data from the nationally representative National Longitudinal Survey of Youth 1997 cohort (NLSY-97), we show that most men in complex families intensively parent the children of one mother while being less involved, or not involved at all, with children by others. Repeated qualitative interviews with 110 low-income noncustodial fathers reveal that men in complex families often engage with and provide, at least to some degree, for all of the biological and stepchildren who live in one mother’s household. These activities often exceed those extended to biological children living elsewhere. Interviews also show that by devoting most or all of their resources to the children of just one mother, men in complex families feel successful as fathers even if they are not intensively involved with their other biological children.
Conclusion
Authors: St. John Edward P.
Published: June 2014

In this chapter, the author synthesizes the themes from the previous articles. Review and commentary on these articles focuses on (a) understanding the challenge of college readiness emerging from these articles and (b) actionable insights, focusing on what we can learn from these articles to inform both research and practice.
Beauty and Status
Authors: McClintock Elizabeth Aura
Published: June 2014

Scholars have long been interested in exchange and matching (assortative mating) in romantic partner selection. But many analyses of exchange, particularly those that examine beauty and socioeconomic status, fail to control for partners’ tendency to match each other on these traits. Because desirable traits in mates are positively correlated between partners and within individuals, ignoring matching may exaggerate evidence of cross-trait beauty-status exchange. Moreover, many prior analyses assume a gendered exchange in which women trade beauty for men’s status, without testing whether men might use handsomeness to attract higher-status women. Nor have prior analyses fully investigated how the prevalence of beauty-status exchange varies between different types of couples. I use data from the National Longitudinal Study of Adolescent Health Romantic Pair Sample, a large ( N = 1,507), nationally representative probability sample of dating, cohabiting, and married couples, to investigate how often romantic partners exchange physical attractiveness and socioeconomic status, net of matching on these traits. I find that controlling for matching eliminates nearly all evidence of beauty-status exchange. The discussion focuses on the contexts in which beauty-status exchange is most likely and on implications these results have for market-based and sociobiological theories of partner selection.
High Clopidogrel Dose in Patients With Chronic Kidney Disease Having Clopidogrel Resistance After Percutaneous Coronary Intervention
Authors: Liang Jing , Wang Zhijian , Shi Dongmei , Liu Yuyang , Zhao Yingxin , Han Hongya , Li Yueping , Liu Wei , Zhang Linlin , Yang Lixia , Zhou Yujie
Published: June 2014

We evaluated the impact of clopidogrel 150 mg/d in patients with chronic kidney disease (CKD) having clopidogrel resistance (CR) after percutaneous coronary intervention (PCI); 1076 consecutive patients with coronary artery disease (CAD) having CKD were enrolled. Maximal platelet aggregation (MPA) was assessed before, 24 hours, and 30 days after a 300-mg loading dose of clopidogrel prior to PCI. After PCI, 370 patients with CR were randomized to receive clopidogrel 75 mg/d (n = 184) or 150 mg/d (n = 186) for 30 days. Stent thrombosis (ST), major adverse cardiac events (MACEs), and bleeding were analyzed after 1 month. Patients in the 150 mg group had significant lower rates of ST and MACE. There was no significant difference in major or minor bleeding. Patients in the 150 mg group had lower MPA and greater inhibition of platelet aggregation. One-month administration of 150 mg/d of clopidogrel decreases the rate of ST and MACE without increasing bleeding in patients with CKD having CR after PCI.
Dysphonia and Vocal Fold Telangiectasia in Hereditary Hemorrhagic Telangiectasia
Authors: Chang Joseph , Yung Katherine C.
Published: June 2014

Objective:

This case report is the first documentation of dysphonia and vocal fold telangiectasia as a complication of hereditary hemorrhagic telangiectasia (HHT).

Methods:

Case report of a 40-year-old man with HHT presenting with 2 years of worsening hoarseness.

Results:

Hoarseness corresponded with a period of anticoagulation. Endoscopy revealed vocal fold scarring, vocal fold telangiectasias, and plica ventricularis suggestive of previous submucosal vocal fold hemorrhage and subsequent counterproductive compensation with ventricular phonation.

Conclusion:

Hereditary hemorrhagic telangiectasia may present as dysphonia with vocal fold telangiectasias and place patients at risk of vocal fold hemorrhage.