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Let A be a sequence of positive integers and P(A) be the set of all integers which are the finite sum of distinct terms of A. Let B = { b 1 < b 2 < ⋯ } be a sequence of positive integers with b 1 ∈ { 4 , 7 , 8 } ∪ [ 11 , + ∞) . By observing the results of Chen and Fang [2], Fang and Fang [4] found that 3 b 1 + 5 is the critical value for b2 such that there exists a sequence A of positive integers for which P (A) = N \ B . For b 2 = 3 b 1 + 5 , they considered the inverse problem and determined the critical value for b3. Also, for b 2 ≥ 3 b 1 + 5 , they asked for the critical value for b3. In this paper, we solve this problem. [ABSTRACT FROM AUTHOR]

Alloys with ultra-high strength and sufficient ductility are highly desired for modern engineering applications but difficult to develop. Here we report that, by a careful controlling alloy composition, thermomechanical process, and microstructural feature, a Co-Cr-Ni-based medium-entropy alloy (MEA) with a dual heterogeneous structure of both matrix and precipitates can be designed to provide an ultra-high tensile strength of 2.2 GPa and uniform elongation of 13% at ambient temperature, properties that are much improved over their counterparts without the heterogeneous structure. Electron microscopy characterizations reveal that the dual heterogeneous structures are composed of a heterogeneous matrix with both coarse grains (10∼30 μm) and ultra-fine grains (0.5∼2 μm), together with heterogeneous L12-structured nanoprecipitates ranging from several to hundreds of nanometers. The heterogeneous L12 nanoprecipitates are fully coherent with the matrix, minimizing the elastic misfit strain of interfaces, relieving the stress concentration during deformation, and playing an active role in enhanced ductility. Improving both strength and ductility simultaneously in structural metals and alloys remains a challenge. Here, the authors design a heterogeneous structure in a Co-Cr-Ni alloy that results in ultrahigh strength and significant uniform elongation. [ABSTRACT FROM AUTHOR]

Two new complexes, namely, [Cd2(L1)2(NCS)4(DMF)2] · 4H2O (I) and {[Zn3(L2)4(SO4)3(H2O)8] · 3DMF · 6H2O} n (II) have been synthesized through self-assembly of Cd(II) or Zn(II) salts with ferrocenyl ligands bearing pyrazolyl pyridine substituents. The two compounds were characterized by IR spectra, element analysis, X-ray powder diffraction, single-crystal X-ray diffraction (СIF files CCDC nos. 949526 (I), 949527 (II)), and thermogravimetric analysis. Complex I crystallizes in the monocline space group P21/c and exhibits a discrete dinuclear structure. The adjacent dinuclear molecules are packed into a 1D linear chain through the hydrogen-bond interactions. Complex II is a neutral one-dimensional infinite zigzag coordination chain. The 3D packing diagram of II contains two types of voids and the solvated DMF and water molecules filled them and stabilized by the hydrogen bonds. In addition, the redox properties of both complexes I and II have also been investigated. [ABSTRACT FROM AUTHOR]

Paroxysmal kinesigenic dyskinesia is a rare episodic movement disorder that can be isolated or associated with benign infantile seizures as part of choreoathetosis syndrome. Mutations in the PRRT2 gene have been recently identified as a cause of paroxysmal kinesigenic dyskinesia and infantile convulsion and choreoathetosis (ICCA). We reported a PRRT2 heterozygous mutation (c.604-607delTCAC, p.S202Hfs*25) in a 3-generation Chinese family with infantile convulsion and choreoathetosis and paroxysmal kinesigenic dyskinesia. The mutation was present in 5 family members, of which 4 were clinically affected and 1 was an obligate carrier with reduced penetrance of PRRT2. The affected carriers of this mutation presented with a similar type of infantile convulsion during early childhood and developed additional paroxysmal kinesigenic dyskinesia symptoms later in life. In addition, they all had a dramatic clinical response to oxcarbazepine/phenytoin therapy. Reduced penetrance of the PRRT2 mutation in this family could warrant genetic counseling. [ABSTRACT FROM AUTHOR]

We report an experimental study on the dynamic thermomagnetic (TM) reversal mechanisms at around Curie temperature (Tc) for isolated 60 nm pitch single-domain [Co/Pd] islands heated by a 1.5 μ m spot size laser pulse under an applied magnetic reversal field (Hr). Magnetic force microscopy (MFM) observations with high resolution MFM tips clearly showed randomly trapped nonswitched islands within the laser irradiated spot after dynamic TM reversal process with insufficient Hr strength. This observation provides direct experimental evidence by MFM of a large magnetization switching variation due to increased thermal fluctuation/agitation over magnetization energy at the elevated temperature of around Tc. The average percentage of non-switched islands/magnetization was further found to be inversely proportional to the applied reversal field Hr for incomplete magnetization reversal when Hr is less than 13% of the island coercivity (Hc), showing an increased switching field distribution (SFD) at elevated temperature of around Tc (where main contributions to SFD broadening are from Tc distribution and stronger thermal fluctuations). Our experimental study and results provide better understanding and insight on practical heat assisted magnetic recording (HAMR) process and recording performance, including HAMR writing magnetization dynamics induced SFD as well as associated DC saturation noise that limits areal density, as were previously observed and investigated by theoretical simulations. [ABSTRACT FROM AUTHOR]

Aim To investigate the role of the Ca2+-Mg2+ ion channel TRPM7 in the proliferation, migration and osteogenic differentiation of human dental pulp stem cells ( hDPSCs). Methodology Immunohistochemistry was used to localize expression of TRPM7 in human dental pulp tissues and in cultured hDPSCs. Isolated hDPSCs were infected with recombinant lentiviruses expressing short hairpin RNA (shRNA) specific for TRPM7, or control shRNA, in order to suppress TRPM7 mRNA expression and investigate its functional role. The proliferation of the shRNA-infected hDPSCs was evaluated using both an MTT assay to measure viable cell numbers and cell cycle analysis. Cell migration was assessed using a transwell assay. The dynamic mRNA expression of TRPM7 during osteogenic differentiation of hDPSCs and the effect of shRNA specific for TRPM7 on hDPSC osteogenic differentiation were evaluated by real-time PCR. Results TRPM7 expression was widespread in human dental pulp tissue and was detected mainly in the cytomembrane and cytoplasm of hDPSCs. Suppression of TRPM7 inhibited both the proliferation and the migratory capacity of hDPSCs. TRPM7 mRNA expression was elevated during osteogenic differentiation of hDPSCs. TRPM7-specific shRNA inhibited osteogenic differentiation of hDPSCs, with downregulated mRNA expression of the osteogenic markers alkaline phosphatase (ALP), dentine sialophosphoprotein (DSPP), bone sialoprotein (BSP), runt-related transcription factor (RUNX2) and osterix (OSX). Conclusions TRPM7 was involved in the regulation of hDPSC proliferation, migration and osteogenic differentiation and may play a role in the dental pulp repair process. [ABSTRACT FROM AUTHOR]

Objectives To assess the frequency of karyotype abnormalities and chromosome 22q11.2 deletion syndrome among fetuses with abnormal cardiac ultrasound findings, and to evaluate the clinical value of chromosomal microarray-based analysis (CMA) in the study of such pregnancies. Methods First, we carried out retrospective analysis of karyotype abnormalities and 22q11.2 deletion syndrome cases diagnosed between January 2009 and December 2011 in our center among fetuses with abnormal cardiac ultrasound findings (n=276). Second, CMA was performed in 51 of the fetuses with such findings, normal karyotype and negative or no 22q11.2 deletion syndrome study, and in the only fetus with a heart defect and an apparently balanced de novo chromosomal rearrangement. Results Out of the 276 pregnancies with abnormal cardiac ultrasound findings, karyotyping revealed a chromosomal abnormality in 44 (15.9%). Of fetuses with normal karyotype in which 22q11.2 deletion syndrome studies were performed, 6.4% (5/78) had this microdeletion syndrome. Among fetuses with abnormal cardiac findings, normal karyotype and negative or no 22q11.2 deletion syndrome study that underwent CMA, the detection rate of pathogenic copy number variants not detected by conventional cytogenetics was 2.0% (1/51), and no variants of uncertain clinical significance were found. In the fetus with a heart defect and an apparently balanced de novo chromosomal rearrangement, CMA revealed that the rearrangement was not truly balanced. Conclusions In the assessment of genetic abnormalities in pregnancies with abnormal cardiac ultrasound findings, the diagnostic yield may be increased by 2% if CMA is used as a complementary tool to conventional cytogenetics. Our results suggest that CMA could be a good alternative to karyotyping in these pregnancies. [ABSTRACT FROM AUTHOR]

The effect of a superconducting overlaid layer on exchange bias in antiferromagnet/ferromagnet bilayers is investigated through temperature-dependent electrical transport measurements. It is found that below the transition temperature of the superconductor, the exchange bias field (He) and coercivity (Hc) of the bilayer vary randomly in repeated magnetoresistance measurements, while they remain as constant above the superconductor transition temperature. We attribute this to the instability of spin structure of the antiferromagnet induced by the superconductor, which in turn affects the exchange bias at the antiferromagnet/ferromagnet interface. Micromagnetic modeling is performed to assist the interpretation of the experimental results. [ABSTRACT FROM AUTHOR]

Yu HE, Hawash K, Picker J, Stoler J, Urion D, Wu B-L, Shen Y. A recurrent 1.71 Mb genomic imbalance at 2q13 increases the risk of developmental delay and dysmorphism. Whole genome profiling such as array comparative genomic hybridization has identified novel genomic imbalances. Many of these genomic imbalances have since been shown to associate with developmental delay, intellectual disability and congenital malformation. Here we identified five unrelated individuals who have a recurrent 1.71 Mb deletion/duplication at 2q13 (Human Genome Build 19: 111,392,197-113,102,594). Four of these individuals have developmental issues, four have cranial dysmorphism. Literature review revealed 14 more cases that had similar genomic imbalances at 2q13. Many of them had developmental delay and dysmorphism. Taken together, 93% and 63% of individuals with this genomic imbalance displayed impaired developmental skills and/or abnormal facial features respectively. This copy number variant (CNV) has not been reported in normal control databases. We, therefore, propose that CNV in this region is a risk factor for developmental delay and dysmorphism. [ABSTRACT FROM AUTHOR]

This article proposes a method to determine energy-optimal low-thrust trajectories for satellite formation manoeuvre in the presence of the J2 effect. This manoeuvre is cast as a non-linear optimization problem with a desired final satellite formation configuration subjecting to collision avoidance constraint. With this proposed approach, the deputy satellite is manoeuvred into a quasi-periodic desired final formation with respect to the chief satellite in the presence of the J2 effect. Resulting non-linear optimal control problem is converted into non-linear programming (NLP) problem by a direct transcription method called Legendre pseudospectral method. The NLP problem is then solved using a sparse non-linear optimization algorithm. Simulation results validate the proposed optimal trajectory design for formation manoeuvres in the presence of the J2 effect. [ABSTRACT FROM AUTHOR]

We studied electrical transport characteristics of lateral superconductor (SC)-ferromagnet (FM)-superconductor devices which were found to exhibit two strikingly different differential resistance states at zero field. The key difference between these states is that the critical current ( I) is dramatically lower for one state (state 2) than the other (state 1). Moreover, state 2 exhibits a higher zero bias resistance than state 1. We explain this as an effect of magnetic field from the frozen flux in SC on the Andreev reflection process at the SC-FM interface. The magnetoresistance (MR) curves at different dc current biases are nonhysteretic and symmetric with respect to zero field axis when the device is at state 1. In contrary to this, MR curves at state 2 are asymmetric and show a pronounced hysteresis at high bias current. These effects indicate a coupling between applied field and frozen flux, which affects the transport characteristics of the SC-FM interface. [ABSTRACT FROM AUTHOR]

Jaakkola E, Mustonen A, Olsen P, Miettinen S, Savuoja T, Raams A, Jaspers NGJ, Shao H, Wu BL, Ignatius J. ERCC6 founder mutation identified in Finnish patients with COFS syndrome. Cerebro-oculo-facio-skeletal (COFS) syndrome is an autosomal recessive disorder characterized by microcephaly, congenital cataracts, facial dysmorphism, neurogenic arthrogryposis, growth failure and severe psychomotor retardation. We report a large consanguineous pedigree from northern Finland with six individuals belonging into four different sibships and affected with typical COFS syndrome phenotype. Two deceased patients have been published previously in 1982 as the first cases exhibiting cerebral calcifications typical for this disorder. Two living and one of the deceased patients were all shown to possess a novel homozygous mutation in the ERCC6 [Cockayne syndrome B (CSB)] gene, thereby confirming the diagnosis on molecular genetic level even for the earlier published cases. Genealogical investigation showed a common ancestor living in a northeastern village in Finland in the 18th century for all six patients implying a founder effect. [ABSTRACT FROM AUTHOR]

Miscarriage is the spontaneous loss of an embryo or fetus before the 20th week of pregnancy. Most miscarriages occur before the end of the first trimester (<13 weeks). Although many risk factors relate to this occurrence, genetic factors play the most important role. Chromosomal abnormalities, including both numerical and structural anomalies, underlie the majority of miscarriages. In this study, we employed a comprehensive approach using cytogenetic karyotyping, polymerase chain reaction (PCR)-based genotyping, and microarray-based comparative genomic hybridization (arrayCGH) in combination to analyze chromosomal profiles of 115 first-trimester miscarriages of Chinese women. Seventy cases (61%) were found to have chromosomal anomalies, of which 90% were numerical and 10% were structural. Cytogenetic karyotyping identified 78.6% (55/70), PCR assays 2.9% (2 triploids), and arrayCGH 18.6% (13/70) of the anomalies. In this study, a microdeletion of 108 kb and four microduplications sizing from 300 to 1460 kb were observed. An advantage of using this combination approach is that microsatellite genotyping and arrayCGH can be accomplished in spite of culture failure and maternal cell contamination. In addition, arrayCGH can detect submicroscopic chromosomal anomalies and gene dosage alterations. [ABSTRACT FROM AUTHOR]

Aluminosilicate refractory waste was used to prepare high performance ceramic ball grinding media with 75% Al2O3. The influence of milling time on the particle size of raw materials, the sintering temperature, and performance of ceramic balls were studied. Results show that with increasing milling time the particle size of the raw materials decreased, resulting in a decrease of ceramic ball sintering temperature and an increase in wear resistance and volume density. The wear rate and volume density of balls prepared by milling the materials for 72 h were 0.01886 %h and 3.374 g/cm³, respectively. [ABSTRACT FROM AUTHOR]

Aim To study the mineralization ability and the dynamic changes of intracellular and extracellular concentrations of calcium ions in the odontoblast-like cell line MDPC-23 affected by antisense oligonucleotide (AS-ODN) against mouse dentine matrix protein 1 (DMP1). Methodology The expression of DMP1 in MDPC-23 cells was detected by an immunohistochemical method and its blocking outcome by the Western blot method. The alkaline phosphatase (ALP) activity, size and number of mineralized nodules, and the intracellular free ([Ca2+]if), total ([Ca2+]it) and the extracellular ([Ca2+]e) calcium ion concentrations in MDPC-23 cells in the experimental group affected with AS-ODN were compared with those in the control group (paired-samples t-test). Results Dentine matrix protein 1 was stably expressed in a stable way in MDPC-23 cells; the expression was only just detectable at 12 h and became negative after 24 h affected by AS-ODN. Compared with the control groups, ALP activity of MDPC-23 cells in the AS-ODN group was decreased ( P < 0.05), and both the number and size of mineralized nodules were smaller than those in the control group. [Ca2+]if in the AS-ODN group increased and then decreased after 24 h. [Ca2+]it dropped substantially to the lowest point at 24 h ( P < 0.01). [Ca2+]e increased before treatment for 24 h and then dropped, however, it was still higher than that of the control group. Conclusions Antisense oligonucleotide against DMP1 could decrease mineralization ability and affect the intracellular and extracellular concentrations of calcium ions in MDPC-23 cells. This would indicate that DMP1 regulates the metabolism and transportation of calcium ions in odontoblasts, and thus boosts dentine mineralization. [ABSTRACT FROM AUTHOR]

Sodium fluoride-loaded gelatin microspheres (NaF-GMS) were prepared using double-phase emulsified condensation polymerization. The average diameter of microspheres was (11.33 ± 5.56) μm. The drug content and encapsulation efficiency were 8.80% and 76.73%, respectively. The fluoride releasing profiles of NaF-GMS in physiological saline and artificial saliva (pH 4.5, pH 6.8) showed that NaF-GMS had a sustained-release property and Fluoride release rate was increased in pH 4.5 artificial saliva. Experiments conducted in rabbits' oral cavity using NaF-GMS and NaF solution as control revealed NaF-GMS should maintain oral Fluorid- retention longer than NaF solution. Cariostatic abilities of NaF-GMS including demincralization prohibition in vitro, Buoride deposition in artificial dental plaque and the ability of targeting to cariogenic bacteria were investigated in artificial dental plaque. The results indicated NaF-GMS with lower fluoride concentrations could achieve equivalent cariostatic effect to the concentrated NaF solution, at the same time, could prolong fluoride retention in dental plaque. Microscopic observation showed that NaF-GMS carrying fusion protein of glucan-binding domain could adhere more bacteria than NaF-GMS and this might indicate the possibility of targeting to cariogenic bacteria when NaF-GMS were properly modified. [ABSTRACT FROM AUTHOR]

The posterior cricoarytenoid (PCA) muscle is known to be active during phonation and respiration. The presence of muscle compartments (bellies) that might subserve these functions was investigated in the canine PCA by anatomical dissection and muscle fiber histochemistry. Five PCA muscles were microdissected and the origins and insertions of all muscle bundles were recorded. An additional six PCA muscles were frozen, sectioned, and stained for adenosine triphosphatase (ATPase) activity. The total number of fast- and slow-twitch fibers were counted and their proportion was determined for each region of the muscle. The PCA muscle was found to contain three distinct neuromuscular compartments. The vertical compartment is oriented at 24 degrees from true vertical, inserts on the lateral aspect of the muscular process of the arytenoid, and is composed of 65% type 2 (fast) muscle fibers. The oblique is oriented at 44 degrees from vertical, inserts on the top of the muscular process of the arytenoid, and is composed of 77% type 2 muscle fibers. The horizontal is oriented at 63 degrees from vertical, inserts on the medial aspect of the muscular process of the arytenoid, and is composed of 59% type 2 muscle fibers. The cricoarytenoid joint is capable of three arcs of motion and the physical arrangement of each compartment appears to correspond to each of these motions. Moreover, the histochemical profiles show that the activity of the three bellies is quite different. These results suggest that the different compartments of the PCA perform distinctive motions during phonation and inspiration. [ABSTRACT FROM AUTHOR]

There is anatomical and histological evidence for three functionally distinct muscle bellies in the canine posterior cricoarytenoid (PCA) muscle. This study attempted to define the exact nerve branching pattern to each muscle belly in 10 dogs using a modification of Sihler's neural staining technique. The results are presented here as photographs and schematic nerve maps which illustrate the following points. 1. the final terminal branches within the PCA do correspond to the three bellies of the PCA; 2. the initial nerve branch to the PCA is usually composed of multiple fascicles which rearrange before their final branching to the three bellies; 3. there is tremendous variability of the nerve branching patterns including bilateral asymmetry within the same animal; 4. the terminal branching within each belly can be surprisingly complex and contain multiple anastomoses; 5. the fast- and slow-twitch bellies of the PCA have different terminal branching patterns. These results support the functional subdivision of the canine PCA into three distinct neuromuscular compartments. This microanatomical technique appears useful for studying the basic neuromuscular organization of laryngeal muscles and their developmental and pathological changes. [ABSTRACT FROM AUTHOR]

We use lateral superconductor (SC)-ferromagnet (FM)-SC device to probe the magnetization reversal process of micron sized FM disk. Upon decreasing external magnetic field from saturated state, a buckling pattern forms first. The onset of buckling pattern and its switching to vortex state are studied with the help of Andreev conductance of the SC-FM interface below the critical temperature (Tc) of SC and the magnetoresistances both below and above the Tc. In the latter case, micromagnetic modeling has been carried out to interpret the experimental results by taking into account the current distributions when the electrodes are at different states. [ABSTRACT FROM AUTHOR]

High dielectric constant and low loss ceramics with composition Ba2La3Ti3TaO15 have been prepared by a conventional solid-state ceramic route. This compound adopts A5B4O15 cation-deficient hexagonal perovskite structure. The dielectric properties of dense ceramics sintered in air at 1520°C have been characterized at microwave frequencies. It shows a relative dielectric constant of ∼45, quality factor Qu× f of ∼26 828 GHz and temperature variation of resonant frequency of −0.97 ppm/°C. [ABSTRACT FROM AUTHOR]

Effect of antiferromagnet on superconductivity has been investigated in IrMn/Nb bilayers. Significant suppression of both transition temperature (Tc) and lower critical field (Hc1) of Nb is found in IrMn/Nb bilayers as compared to a single layer Nb of same thickness; the suppression effect is even stronger than that of a ferromagnet in NiFe/Nb bilayers. The addition of an insulating MgO layer at the IrMn-Nb interface nearly restores Tc to that of the single layer Nb, but Hc1 still remains suppressed. These results suggest that, in addition to proximity effect and magnetic impurity scattering, magnetostatic interaction also plays a role in suppressing superconductivity of Nb in IrMn/Nb bilayers. In addition to reduced Tc and Hc1, the IrMn layer also induces broadening in the transition temperature of Nb, which can be accounted for by a finite distribution of stray field from IrMn. [ABSTRACT FROM AUTHOR]