Solid-state Assembly Research Articles

Loss of Peristaltic Reserve, Determined by Multiple Rapid Swallows, Is the Most Frequent Esophageal Motility Abnormality in Patients With Systemic Sclerosis.

We assessed peristaltic reserve using multiple rapid swallows (MRS) during esophageal high-resolution manometry (HRM) of 111 patients with systemic sclerosis (89 women; ages, 42-64 y). We performed a retrospective analysis of HRM studies that included MRS in patients with systemic sclerosis, performed at 2 tertiary referral centers, and compared data with those from 18 healthy volunteers (controls). HRM findings were analyzed according to the Chicago Classification to provide an esophageal motility diagnosis. Response to MRS was evaluated for the presence of contraction and for augmentation, defined as the distal contractile integral after MRS greater than the median distal contractile integral of 10 supine swallows. Esophageal motility diagnoses included 41% with absent contractility, 31% with normal motility, 23% with ineffective esophageal motility, and 5% that met the criteria for other esophageal motility disorders. Contraction (37%) and peristaltic augmentation (18%) after MRS were observed less frequently in patients with systemic sclerosis than in controls (83% and 100%, respectively). Impaired peristaltic reserve, as assessed with MRS during HRM, is therefore the most common esophageal motility finding among patients with systemic sclerosis.

Ring size effect on the solid state assembly of propargyl substituted hexa- and octacyclic peptoids

The investigation of the solid state assembly of propargyl substituted hexa- and octacyclic peptoids highlights the effect of ring size in determining the packing arrangement of the macrocycles. A layered arrangement is obtained in the case of the hexacyclic peptoid 1 and a tubular arrangement in the case of the octacyclic peptoid 2. Guest molecules either intercalate between the layers as in 1 or are located within the peptoid nanotube as in 2.

Solid-state assembly of a resorcin[6]arene in twin molecular capsules

The solid state structures of a resorcin[6]arene macrocycle crystallized in two different forms are here reported. In both instances, the molecule adopts a pinched cone conformation very similar to that of p-tert-butylcalix[6]arene. In one case, the resorcin[6]arene macrocycle self-assembles in a molecular capsule able to host toluene and ethyl acetate solvent molecules.

Optimization of fatique validation cost for redesigned transport aircraft

An approach to fatigue validation of transport aircraft redesigned structure based on the data of endurance tests of basic aircraft, computational and experimental analyses, ground-based and flight tests of modified aircraft that do not require building and testing of a full-scale modified airframe is proposed in the paper. An example of a modified aircraft developed at Beriev Aircraft Company is presented. Components of a computational cluster that ensures calculation and postprocessing of models of the required dimensions are chosen. The advantages of using a solid model in commercial production of aircraft are demonstrated. Prospective use of solid-state assembly for damage diagnosis using the criterion of variations in the forms of natural vibration of a structure with cracks in operation is shown. Algorithms and software for the identification of vibration forms and frequencies of aircraft in flight under atmospheric turbulence are developed on the basis of the analysis of the structures response to wide-band disturbance using up-to-date digital measuring equipment. Ways of taking into account the damage accumulated in operation not only by operating time (flight hours, number of landings), but also by the equivalent bending moment in the control sections of the airframe are presented. The implementation of the proposed technologies will make it possible to obtain economical effect at all stages of the product life cycle, from design to operation.

Solid-State Lithium Polymer Secondary Batteries

Energy storage plays a vital role in everyday life. As the worlds need for energy has increased so has the demand for better performing batteries, batteries that can defy conventional constraints and batteries that have improved safety. Currently Lithium ion batteries dominates this sector due to their high specific energy and high specific power.However they are currently not without faults, improving on their design and construction would be greatly beneficial in certain industries. For example, non-metallic batteries could be useful when a reduction in interference with an antennae signal is desired, another possibility is to create a polymer which is both ionic and electrically conducting as this allows the removal of current collectors from a conventional design again reducing interference and also the number of interfaces in the battery construction. In addition to this, polymer electrolytes could offer a viable design solution for when irregularly shaped batteries are necessary and this would also remove the issue of combustible electrolytes. The objectives are to synthesise mixed conducting polymers and electrochemically test them, then assemble a solid-state Lithium polymer battery. Results based on these systems will be presented are the battery cycles giving both individual polymer performance and again with the full solid state assembly.

Fabrication of ultra-thin polyrotaxane-based films via solid-state continuous assembly of polymers.

Surface-confined ultra-thin polyrotaxane (PRX)-based films with tunable composition, surface topology and swelling characteristics were prepared by solid-state continuous assembly of polymers (ssCAP). The PRX-based films supported cell attachment, and their degradation in biological media could be tuned. This study provides a versatile nano-coating technology with potential applications in biomedicine, including tissue engineering and medical devices.

Solid-state assembly of carboxylic acid substituted pillar[5]arene and its host–guest complex with tetracaine

The first examples of carboxylic acid substituted pillar[5]arene structures in the form of its inclusion complexes with ethanol and the anesthetic drug tetracaine are reported.

Facile fabrication of flexible all solid-state micro-supercapacitor by direct laser writing of porous carbon in polyimide

We demonstrate the fabrication of flexible micro-supercapacitors based on laser carbonization of polyimide sheets. Localized pulsed laser irradiation rapidly converts the pristine polyimide surface into an electrically conductive porous carbon structure in ambient conditions. Thus, the polyimide sheet acts as both a precursor for the carbonization and a flexible substrate. Effects of various laser parameters are examined to enhance electrical properties and morphology of the carbonized structures. The interdigitated electrode patterns are produced directly on the polyimide sheets by programmed laser scanning. A solid-state polyvinyl alcohol–phosphoric acid gel electrolyte is introduced into the active electrode area to realize a flexible all solid-state microcapacitor assembly. Cyclic voltammetry measurements exhibit the expected electrical double layer behavior. The specific capacitance of the supercapacitors reaches ∼800μF/cm2 at a voltage scan rate of 10mV/s with good capacitance retention under mechanical bending. The proposed laser-based approach enables facile fabrication of flexible micro-supercapacitors without tedious photolithographic patterning of porous carbon and metal current collectors.

Experimental and Computational Study of Counterintuitive ClO4–···ClO4– Interactions and the Interplay between π+–π and Anion···π+ Interactions

The novel noncovalent interactions between the charged and neutral aromatic rings and with anions are utilized to design the solid-state assembly of triply protonated PTPH3 (PTP = 4′-(4-pyridyl)-3,2′:6′,3″-terpyridine) with H2O and three ClO4–, which is synthesized and characterized by single-crystal X-ray diffraction analysis. Crystallography reveals that the π+–π+, π+–π, and various anion···π interactions are the major driving forces in the stabilization of the self-assembled structure. In the title complex, a layered assembly is formed through the mutual influence of π+–π+ and π+–π interactions. The anions are interacting with the charged π-acceptors, which are again stabilized through π+–π interactions. Therefore, the overall stabilization is governed through π+–π/π–π+, (π+–π+)n, and anion···π+/π+–π/π–π+ networks in the solid state. The interaction energies of the main driving forces observed in the crystal structure have been calculated using density functional theory. In addition, the short O···O co...

Assembling nanotubes with cyclic peptoids

Cyclic alpha-peptoids hold the attention of both synthetic and supramolecular chemists for their biostability and potential diversity but also for their elegant and intriguing architectures.[1] Peptoids differ from peptides in the side chains, which are shifted by one position along the peptide backbone to the nitrogen atom to give N-substituted oligoglycine. The lack of the amide proton prevents the formation of NH···OC hydrogen bonds and weaker interactions, as CH···OC hydrogen bonds and CH-pi interactions, play a key role. Inter-annular CH···OC hydrogen bonds can provide face to face or side by side arrangement of macrocycles mimicking beta-sheet secondary structure in proteins.[2] In particular, the role of side chains in the solid state assembly of peptoid macrocycles will be discussed to show how they can promote the formation of a peptoid nanotube by acting as pillars, extending vertically with respect to the macrocycle planes. [3] Examples of the solid state assembly of free and metallated cyclic peptoids will be reported to show their extreme versatility as building blocks for designing new materials, with novel chemical properties and defined biological activities. In particular the first crystal structure of a recently synthesized novel cyclic alpha-peptoid, containing open channels with a radius of approximately 7 Å, will be discussed as a case of the successful engineering of cyclopeptoid crystals. In figure it is shown the channel void surface as seen along the a axis (0.0003 au, CrystalExplorer 3.1). The results of recent variable temperature high resolution XRPD measurements performed at ESRF beamline ID31 will be also reported to highlight the unusual thermal stability of this class of compounds and how the mobility of the side chains may be exploited to prepare new functional materials. EU FP7-People- IRSES grant number 319011 is gratefully acknowledged.

Exploration of supramolecular interactions in a series of UO22+hybrid materials

Previous work from our group has focused on uranyl hybrid materials with para-substituted halogen benzoic acids.1 Applying a `cap and link' strategy we have successfully controlled the nuclearity of UO22+ in a series of coordination polymers and Ln3+ in a family of molecular materials.2,3 Here we have expanded on this strategy and produced a series of 12 unique uranyl hybrid materials. The hydrothermally synthesized complexes all feature bromo-substituted benzoic acid linkers and the UO22+ metal centers are capped with a chelating N-donor. Single crystal X-ray diffraction analyses of these materials allowed for the exploration of the structural relationship between the benzoic acid group and the chelating N-donor as well as the influence of pH on uranyl speciation. At an unadjusted pH (~3) a mix of molecular monomers and dimers are observed while at higher pH (5-6) molecular uranyl dimers are exclusively produced. A systematic study of the supramolecular interactions that governed extended solid-state assembly was investigated by varying the bromine position on the benzoic acid groups along with the chelating N-donor with pH. Assembly via halogen-halogen, halogen-π, π-π, and halogen-oxygen interactions was observed and the influence of these interactions on uranyl emission was also investigated. Solid-state luminescence and lifetime measurements were used to explore the effects of speciation and chelating N-donor ligands on the spectroscopic properties of the uranyl cation.

Parallel recognition of cancer cells using an addressable array of solid-state micropores

Early stage detection and precise quantification of circulating tumor cells (CTCs) in the peripheral blood of cancer patients are important for early diagnosis. Early diagnosis improves the effectiveness of the therapy and results in better prognosis. Several techniques have been used for CTC detection but are limited by their need for dye tagging, low throughput and lack of statistical reliability at single cell level. Solid-state micropores can characterize each cell in a sample providing interesting information about cellular populations. We report a multi-channel device which utilized solid-state micropores array assembly for simultaneous measurement of cell translocation. This increased the throughput of measurement and as the cells passed the micropores, tumor cells showed distinctive current blockade pulses, when compared to leukocytes. The ionic current across each micropore channel was continuously monitored and recorded. The measurement system not only increased throughput but also provided on-chip cross-relation. The whole blood was lysed to get rid of red blood cells, so the blood dilution was not needed. The approach facilitated faster processing of blood samples with tumor cell detection efficiency of about 70%. The design provided a simple and inexpensive method for rapid and reliable detection of tumor cells without any cell staining or surface functionalization. The device can also be used for high throughput electrophysiological analysis of other cell types.

Magnetostructural effects of changing spin unit structure and molecular connectivity on 1H-benzimidazole functionalized radicals

A single hydrogen bonding molecular assembly unit (benzimidazole=BIm) was used for solid state assembly of different types of radicals connected at different sites on the assembly unit. The effects of changing radical spin unit and molecular connectivity were tested by comparing tetramethylnitronylnitroxide (NN), dimethyloxoverdazyl (mV), and diisopropyloxoverdazyl (iV) spin units attached to BIm at either the 2-position or 5/6-position. The mV systems were not isolated with sufficient purity and stability for crystallographic or magnetic analysis, but chain-type hydrogen bonding was found in the crystal structures of all of the other, stable compounds. Close contacts are induced between radical groups in some cases by the hydrogen bonded chains, giving exchange behavior ranging from essentially isolated spin paramagnetism (BIm2iV) to antiferromagnetic interactions of (−)1–3K.

Solid state assembly of cyclic α-peptoids

In cyclic alpha-peptoids, inter-annular CH⋯OC hydrogen bonds provide face to face or side by side arrangement of macrocycles mimicking the beta-sheet secondary structure in proteins. Side chains may promote the formation of peptoid nanotubes, acting as pillars among neighbouring macrocycles.

Studying of Gastroesophageal Reflux Disease with High-Resolution Esophageal Manometry in Different Positions

Purpose: High-resolution esophageal manometry (HREM) is usually performed in supine position. While it is known that posture has effect on gastroesophageal reflux (GER), studies describing the effect of posture on HRM measurements in gastroesophageal reflux disease GERD are lacking. The aim of this study is to compare the impact of different body positions on HREM recording in patients with GERD. Methods: Prospective study included 42 patients presented with typical and atypical GER symptoms had undergone HREM. A solid-state HREM assembly with 32 circumferential sensors spaced 1 cm apart (Unisensor) was used in the study, plotting graphs with high resolution color topography and pressure waves (GI Solar MMS). HREM recording was done while the patients is fasting and in different positions: recumbent at LT side, RT side, supine and sitting position; 10 minutes each. Patients were given ten 5-ml water swallows in each position. Pressure profiles across the esophagogastric junction (EGJ), upper esophageal sphincter (UES), peristaltic integrity, transient lower esophageal sphincter relaxations (TLESRs) were analyzed and interpreted according to Pandolfino et al, Am J Gastroenterol 2008;103:27. Results: A total of 1680 water swallows in different positions were analyzed. RT recumbent position had the lowest EGJ pressure, and the highest number of TLESRs. On the other hand, change of body position did not significantly change EGJ length, UES pressure, % of peristaltic contractions, and upper and lower body contraction amplitude (table 1). Normal body peristalsis was found in 47.7% of patients, while weak peristalsis with small peristaltic defects, large peristaltic defects, aperistlasis and distal esophageal spasm were found in 26.3%, 14.3%, 2.3%, and 9.4%, respectively. Hiatal hernia was observed manometrically in 14.3% of patients.Table 1: HREM measurements in different body positionsConclusion: RT recumbent position showed the lowest EGJ pressure and the highest number of TLESRs. Sitting, LT recumbent and supine positions did not significantly affect HREM measurements. Ineffective esophageal motility disorder is a common finding with GERD.

How metallation affects solid-state conformation and assembly of hexameric cyclic peptoids

How metallation affects solid-state conformation and assembly of hexameric cyclic peptoids

A Benzaldehyde Derivative as a Chelating Ligand: Helical Manganese(II) Coordination Polymers Assembling into a Porous Solid

A molecular, porous crystalline material constructed from neutral helical coordination polymers incorporating manganese(II) ions and two types of bridging ligands, namely the deprotonated form of 2-hydroxy-5-methoxy-3-nitrobenzaldehyde (HL) and isobutyrate (iB–), has been obtained and structurally characterized. Structural analysis reveals that within the coordination polymer each benzaldehyde derivative ligates two manganese ions in 6-membered chelating rings, and the isobutyrate ligands cooperatively chelate either two or three manganese ions. The solid state assembly of the resulting polymeric chains of formula [Mn4(L)2(iB)6]n (1), described in the polar space group R3c, is associated with tubular channels occupied by MeCN solvent molecules (1·xMeCN; x ≤ 9). TGA profiles and PXRD measurements demonstrate that the crystallinity of the solid remains intact in its fully desolvated form, and its stability and crystallinity are ensured up to a temperature of 190 °C. Gas adsorption properties of desolvated crystals were probed, but no remarkable sorption capacity of N2 and only a limited one for CO2 could be observed. Magnetic susceptibility data reveal an antiferromagnetic type of coupling between adjacent manganese(II) ions along the helical chains with energy parameters J1 = −5.9(6) cm–1 and J2 = −1.8(9) cm–1.

Structural variety of 5-fluoroarene-2-aminopyrimidine in comparison to 2-aminopyrimidine silver(i) coordination polymers: progress report and overview

A variety of fluoroarene-2-aminopyrimidine (FAP) silver(I) coordination polymers (CPs) has been synthesized based on newly synthesized FAP derivatives, namely 5-(p-methoxytetrafluorophenyl)-2-aminopyrimidine (OFAP) and 5-(p-dimethylaminotetrafluorophenyl)-2-aminopyrimidine (NFAP), and different counterions (OTf−, TFA−, ClO4−, NO3−). Their solid-state assembly as well as optical properties in terms of luminescence and infrared (IR) spectroscopy were investigated. Out of the several structures described herein, we obtained isomorphic CPs to previous studies (5, 9), a CP architecture with a short Ag–Ag distance (8, 3.049 A), but also polymorphic crystals of [Ag(nfap)NO3]n (11a, 11b) and the latter showed differences in color and luminescence emission. Polymorphism gives an unparalleled possibility to investigate the origin of such phenomena since luminescence emission is quite often observed for these silver-hybrid solid-state materials and in several cases Ag⋯Ag interactions are attributed for this phenomenon. We show that this explanation does not necessarily have to be the only one. Therefore we focus also on structural relationships and differences in a comprehensive comparison of our own and other known systems to start a more systematic description of the rich coordination capabilities of FAP and congeneric 2-aminopyrimidine (2-AP) based silver(I) coordination polymers and networks. Density functional theory (DFT) calculations with periodic boundary conditions based on a plane wave basis are used to better understand the electronic structure of these crystalline materials. To complete the picture, steady-state spectroscopy studies (UV-Vis, fluorescence, IR) on all ligands and 2-AP itself were conducted as well as re-examination of the first reported CP of 2-AP and AgI under the above aspects.

Tuning the formation of MOFs by pH influence: X-ray structural variations and Hirshfeld surface analyses of 2-amino-5-nitropyridine with cadmium chloride

Self-assembly through tuning the N-donor ligand and coordinative preferences of Cd(II) ions, two metal–organic frameworks, namely {[Cd(L1)2(Cl)2]n·H2O} (1) and {[CdCl3]−·[H(L1)]+}n (2) where, (L1) = 2-amino-5-nitropyridine, have been synthesized at different pH values under hydrothermal conditions and characterized by single crystal X-ray diffraction analyses. The structural diversities of both the complexes reveal that the pH value of the reaction system plays a crucial role in the assembly of metal–organic frameworks (MOFs). The X-ray single crystal diffractions show that the formed two complexes reveal a diversified structure with novel layer architecture. As anticipated, both complexes are interlinked through hydrogen bonding interactions affording supramolecular frameworks, but surprisingly, complex 2 exhibit both anion⋯π and lone-pair⋯π interactions in the solid-state assembly. Intricate combinations of anion⋯π/π⋯lone-pair interactions lead to the remarkable unusual supramolecular framework in 2. Investigation of Hirshfeld surface analysis reveals a much more detailed scrutiny of intermolecular interactions experienced by each complex. The Hirshfeld surface analysis was successfully deployed here to visualize and elaborate the similarities and differences in the molecular environments of the two complexes.

Exploring the solid-state conformation and assembly of cyclic peptoid derivatives

Exploring the solid-state conformation and assembly of cyclic peptoid derivatives