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Self-assembly of the flexible ligand N,N‘-bis(3-pyridylmethyl)thiourea (bpt) with ZnCl2 and CdCl2 in the absence and presence of KSCN yielded a short series of novel complexes (1−4) with macrocyclic, helical, double-helical, and 1D polymeric structures. Different metal ions, hydrogen bonds, and counteranions play significant roles in the final crystal structures. The NCS- anion was found to favor the formation of helical structures, whereas the Cl- anion favored macrocycle formation in the present system. Photoluminescence (PL) measurement results revealed that complex 2 (Zn(bpt)(SCN)2) with a helical structure exhibits enhanced emissions compared to those of the ligand and other complexes. The anion-directed assembly as well as the interesting emissions may provide useful information for further design of metal−organic compounds with novel structures and properties. [ABSTRACT FROM AUTHOR]

Methyl 3,3-dimethoxypropionate was prepared via the oxidation of acrylic acid by oxygen in methanol over PdCl2/CuCl2 catalyst. An acrylic acid conversion of 95.2% with a methyl 3,3-dimethoxypropionate selectivity of 90.6% was obtained at 35 °C and 5 atm. The reaction pathway might be that the esterification of acrylic acid in methanol was the first step, then methyl acrylate reacted with oxygen to form an intermediate aldehyde, which could react with methanol to form methyl 3,3-dimethoxypropionate. [ABSTRACT FROM AUTHOR]

A micromechanics-based model is established. The model takes the interaction among sliding cracks into account, and it is able to quantify the effect of various parameters on the localization condition of damage and deformation for brittle rock subjected to compressive loads. The closed-form explicit expression for the complete stress-strain relation of rock containing microcracks subjected to compressive loads was obtained. It is showed that the complete stress-strain relation includes linear elasticity, nonlinear hardening, rapid stress drop and strain softening. The behavior of rapid stress drop and strain softening is due to localization of deformation and damage. Theoretical predictions have shown to be consistent with the experimental results. [ABSTRACT FROM AUTHOR]

The mechanical behavior of rock under uniaxial tensile loading is different from that of rock under compressive loads. A micromechanics-based model was proposed for mesoscopic heterogeneous brittle rock undergoing irreversible changes of their microscopic structures due to microcrack growth. The complete stress-strain relation including linear elasticity, nonlinear hardening, rapid stress drop and strain softening was obtained. The influence of all microcracks with different sizes and orientations were introduced into the constitutive relation by using the probability density function describing the distribution of orientations and the probability density function describing the distribution of sizes. The influence of Weibull distribution describing the distribution of orientations and Rayleigh function describing the distribution of sizes on the constitutive relation were researched. Theoretical predictions have shown to be consistent with the experimental results. [ABSTRACT FROM AUTHOR]

Discusses the germline mutation of the PTEN gene. Dysregulation of the phosphoinositol-3-kinase/Akt pathway; Occurrence of human lhermitte-Duclos (LDD) disease in adults; Association of LDD or dysplastic gangliocytoma with Cowden syndrome.

Mutations of the PTEN gene are associated with hamartoma-neoplasia syndromes. While germline mutations at this chromosome 10q22-23 locus have been observed in patients with Cowden syndrome (CS) and Bannayan-Riley-Ruvalcaba syndrome (BRR), both of which phenotypes are associated with hamartomata and neoplasia, somatic mutation of PTEN has been established in a wide variety of sporadically occurring neoplasia. CS and BRR share some clinical features, specifically hamartomata and lipomatosis. Investigation of other clinically distinct syndromes associated with lipomatosis and overgrowth has established germline and germline mosaic PTEN mutations in several patients with Proteus syndrome. To this expanding array of clinically distinct phenotypes associated with PTEN mutations, we now report a novel heterozygous germline mutation, H61D, in a patient with features of VATER association with macrocephaly and ventriculomegaly. [ABSTRACT FROM AUTHOR]

Juvenile polyposis syndrome (JPS) is an inherited hamartomatous-polyposis syndrome with a risk for colon cancer. JPS is a clinical diagnosis by exclusion, and, before susceptibility genes were identified, JPS could easily be confused with other inherited hamartoma syndromes, such as Bannayan-Riley-Ruvalcaba syndrome (BRRS) and Cowden syndrome (CS). Germline mutations of MADH4 (SMAD4) have been described in a variable number of probands with JPS. A series of familial and isolated European probands without MADH4 mutations were analyzed for germline mutations in BMPR1A, a member of the transforming growth-factor b receptor superfamily, upstream from the SMAD pathway. Overall, 10 (38%) probands were found to have germline BMPR1A mutations, 8 of which resulted in truncated receptors and 2 of which resulted in missense alterations (C124R and C376Y). Almost all available component tumors from mutation-positive cases showed loss of heterozygosity (LOH) in the BMPR1A region, whereas those from mutation-negative cases did not. One proband with CS/CS-like phenotype was also found to have a germline BMPR1A missense mutation (A338D). Thus, germline BMPR1A mutations cause a significant proportion of cases of JPS and might define a small subset of cases of CS/BRRS with specific colonic phenotype. [ABSTRACT FROM AUTHOR]

Exposure to the fungal pathogen Coccidioides immitis in normal hosts causes primarily self-limited pulmonary disease. We report a case of an immunocompetent patient who developed a Coccidioides-associated iliopsoas abscess with rare intra-abdominal dissemination at least one decade after primary exposure in an area endemic for this fungus. [ABSTRACT FROM AUTHOR]

A silver(I) sulfide species Is now imbedded in a porous coordination network. Such a composite system builds on the molecule tetrakis(methylthio)-1 4-benzenedicarboxate that holds out the hard carboxylate to europium(lll) to form a host net, while taking on AgCl using its soft sulfur side arms. AgCI is then treated with H2S to form the dark-colored Ag2S species, while leaving the hard host net intact and upstanding. This hard-soft duality serves to conjoin the rich electronic flavors of metal chalcogenides and the flexible textures of coordination nets. [ABSTRACT FROM AUTHOR]

The solvothermal reaction of CuSCN and 1,2-bis(diphenylphosphino)ethane (dppe) in mixed solvents acetonitrile/ n-hexane/(methanol or ethanol) gave a honeycomb-like guanidinium cyanocuprate [C(NH 2) 3)]·[Cu 2(CN) 3]. The in situ formed cations C(NH 2) 3+act as templates to direct the formation of the CuCN network in which multiple weak N−H····N/C hydrogen interactions potentially exist between the cations C(NH 2) 3+and the {CuCN} 6rings. [ABSTRACT FROM AUTHOR]

The bifunctional molecule tetrakis(methylthio)-1,4-benzenedicarboxylic acid (TMBD) interacts with the increasingly harder metal ions of CuI, CdII, and ZnII to form the coordination networks of Cu2TMBD, CdTMBD, and Zn4O(H2O)3(TMBD)3, where the carboxyl group consistently bonds to metal ions, while the softer methylthio group binds with preference to the softer metal ions (i.e., chelation to Cu+, single-fold coordination to Cd2+, and nonbonding to Zn2+). Diffuse-reflectance spectra show that the metal-thioether interaction is associated with smaller electronic band gaps of the solid-state networks. [ABSTRACT FROM AUTHOR]

Centripetally shaped molecules are crystallized with AgSbF6 to yield coordination networks featuring novel coordination modes, network connectivity and chiral/helical structures. [ABSTRACT FROM AUTHOR]

Two complexes, 2D [Cu2(CN)2(4-Hpcih)]n and 3D {[Cu2(CN)1.5(4-pcih)]·1.25H2O}n (4-Hpcih = 4-pyridinecarbaldehyde isonicotinoyl hydrazone), were obtained using a synthetic approach of pH-induced formation of metalloligands, successfully demonstrating a strategy to increase structure dimensionality by tuning the number of ligand functional sites. [ABSTRACT FROM AUTHOR]

Solvothermal reactions of CuSCN, metal (Mn2+, Fe2+, Co2+, Ni2+, Cu2+) sulfate, and terpyridine (2,2′:6′,2″-terpyridine or 4′-p-tolyl-2,2′:6′,2″-terpyridine) in the presence of triphenylphosphine yielded a series of hybrid coordination compounds, in which in situ formed metal bis(terpyridine) complex cations are encapsulated by a 3D anionic network or entangled by 2D heartlike networks, forming encapsulation or polypseudorotaxane supramolecules. The complex cations play a role as template to direct the fabrication of the structures. [ABSTRACT FROM AUTHOR]

In this paper, a new type of liquid metal sensor structure is designed and fabricated, in which three microchannels, including one upper channel and two lower channels, are symmetrically arranged in PDMS (polydimethylsiloxane) elastomer. With this structure, pressure can be sensed by detecting resistance, and strain and curvature can also be sensed by detecting capacitance and resistance. The cross-sectional deformational of microchannel 1 in the pressure sensor and the corresponding resistance variation are deduced. The initial capacitance of the strain sensor is increased through the series–parallel connection of three microchannels, which effectively enlarges the capacitance variation per unit strain. Regression analysis of the experimental data is performed, and the univariate nonlinear regression can be simplified to a multivariate linear regression. Moreover, tests on the different commonly employed temperature (0 °C–20 °C) are conducted, it is found from the experimental results that the effect of commonly employed temperature on sensors can be neglected. The experimental data from the pressure sensor are in good agreement with the theoretical curve, especially in the range of 0–4 MPa. Within the measurable strain range (0%–30%), the experimental values of the strain sensors are in good agreement with the theoretical values. In addition, the analytical theory is developed to explain the performance of the sensor, although it can not explain all the observed data well. [ABSTRACT FROM AUTHOR]

This paper reports the fabrication of a hyper-elastic pressure transducer by embedding silicone rubber with micro-channels of conductive liquid metal eGaIn. Micro-channels with dimensions being as small as 300 µm are fabricated by a maskless soft lithography technique. The core of the sensor consists of three layers: the buffer area (top layer), the PDMS membrane layer (middle layer), and the microfluidic layer (bottom layer). Pressures applied on the surface of the elastomer deform the underlying channels and change the electrical resistance. Owing to the arrangement of the buffer strip, stress concentration in the vicinity of micro-channels is eliminated or distinctly reduced compared to the previous studies. At the same time, the stress tends to be more uniform and a certain degree of reduction is emerged at the microfluidic layer. The effects of the buffer zone are well validated by ANSYS workbench. Meanwhile, by adopting trapezoid geometry of micro-channels and the segmented statistical calibration method, the calibration curves and equations are obtained with better linearity and lower hysteresis. Besides, the spring steel shell (50CrVA) with high yield strength is used to bear the primary pressure together with peripheral parts composed of silica gel with good elastic property, which increases effectively the range of the flexible pressure sensor. Finally, theoretical predictions are conducted based on elasticity and contact mechanics. The experimental measured data are in good agreement with the theoretical results. [ABSTRACT FROM AUTHOR]

In the title complex, [Cu2I2(C12H8N2)2]·C2H3N, two CuI atoms are bridged by two I atoms and each CuI atom is chelated by a 1,10-phenanthroline ligand to give four-coordinate tetrahedral geometry. [ABSTRACT FROM AUTHOR]

The molecular aetiology of Proteus syndrome (PS) remains elusive. Germline mutations in PTEN cause Cowden syndrome and Bannayan-Riley-Ruvalcaba syndrome, which are hereditary hamartoma syndromes. Some features--eg, macrocephaly, lipomatosis, and vascular malformations--can be seen in all three syndromes. We examined PTEN in patients with PS and undefined Proteus-like syndromes (PS-like) and identified de-novo germline mutations in two of nine patients with PS and three of five patients with PS-like. Germline PTEN mutation analysis should be done in individuals with PS and PS-like because of its association with increased risk of cancer development and potential of germline-mutation transmission. [ABSTRACT FROM AUTHOR]

Flower-like MoS2 microspheres were successfully synthesized via a facile hydrothermal route followed by annealing treatment using biopolymer (sodium alginate, SA) as an additive. The experimental results indicated that the MoS2 products were of hexagonal phases and had a hierarchical flower-like morphology, which were constructed with MoS2 nanosheets. A probable SA-induced assembly process was presented to account for the formation of the flower-like microspheres. Additionally, as an electrode material for supercapacitor, this MoS2 microsphere delivered a high specific capacitance at a large current density with good cycle ability. [ABSTRACT FROM AUTHOR]

Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) encodes a tumor-suppressor phosphatase frequently mutated in both sporadic and heritable forms of human cancer. Germline mutations are associated with a number of heritable cancer syndromes that are jointly referred to as the ‘PTEN hamartoma tumor syndrome’ (PHTS) and include Cowden syndrome, Bannayan-Riley-Ruvalcaba syndrome, Proteus syndrome, and Proteus-like syndrome. Germline PTEN mutations have been identified in a significant proportion of patients with PHTS; however, there are still many individuals with classic diagnostic features for whom mutations have yet to be identified. To address this, we took a haplotype-based approach and investigated the association of specific genomic regions of the PTEN locus with PHTS. We found this locus to be characterized by three distinct haplotype blocks 33 kb, 65 kb, and 43 kb in length. Comparisons of the haplotype distributions for all three blocks differed significantly among patients with PHTS and controls (P = .0098, P < .0001, and P < .0001 for blocks 1, 2, and 3, respectively). ‘Rare’ haplotype blocks and extended haplotypes account for two-to-threefold more PHTS chromosomes than control chromosomes. PTEN mutation—negative patients are strongly associated with a haplotype block spanning a region upstream of PTEN and the gene's first intron (p = .0027). Furthermore, allelic combinations contribute to the phenotypic complexity of this syndrome. Taken together, these data suggest that specific haplotypes and rare alleles underlie the disease etiology in these sample populations; constitute low-penetrance, modifying loci; and, specifically in the case of patients with PHTS for whom traditional mutations have yet to be identified, may harbor pathogenic variant(s) that have escaped detection by standard PTEN mutation-scanning methodologies. [ABSTRACT FROM AUTHOR]

Cowden syndrome (CS) and Bannayan-Riley-Ruvalcaba syndrome (BRRS) are autosomal dominant hamartoma syndromes. Germline PTEN mutations have been associated with 85% of CS cases and 65% of BRRS cases and also with other disorders, which are collectively referred to as the ‘PTEN hamartoma tumor syndrome.’ The human PTEN gene has been previously found to express two naturally occurring splice variants (SVs). Recently, we identified eight novel naturally occurring PTEN SVs that result in different downstream signaling effects: SV3a, SV3b, SV3c (inclusion of various lengths of intron 3 3′ of exon 3), SV5a, SV5b, SV5c, SV5d (inclusion of various lengths of intron 5 3′ of exon 5), and SVΔEx6 (deletion of exon 6). We therefore sought to characterize the relative expression of 5′, middle, and 3′ full-length PTEN mRNA (FL-PTEN) and also of these eight PTEN SVs in 85 (65 female and 20 male) patients with CS/BRRS (with or without PTEN mutations) compared with 27 controls, using a SYBR green quantitative polymerase chain reaction method. Significantly reduced FL-PTEN levels were found in the probands, compared with those of controls (P<.01 ). Apart from FL-PTEN, SV3a is the most consistently relatively underexpressed in patients compared with controls. The patients showed relative underexpression of SV3a and SV3b and overexpression of SV5b (P = .005, P = .02, and, P = .04, respectively). Indeed, there appears to be an SV expressional genotype-phenotype correlation in which the SV expressional profiles are distinct among CS, CS-like, and BRRS. The reduced FL-PTEN transcript expression, associated with differential expression of PTEN SVs, regardless of PTEN mutation status, supports the concept that modulation of PTEN inactivation may also occur at the transcription level influencing the specific phenotypes seen in these syndromes. [ABSTRACT FROM AUTHOR]