A rare case of a perforated diverticulum of the cecum

A rare case of peritonitis by cecal perforated diverticulum which was diagnosed after surgery by histology is reported. Preoperative diagnosis is often ignored and, in rare cases, is not always clear at laparotomy. Clinical aspects, diagnostic procedures, histological picture and surgical treatment are described. In the literature diverticula are classified as "solitary" and "multiple", "congenital" and "acquired", "true" and "false" and finally "usual type" and "hidden variant". The treatment of cecal acute diverticulitis is, in the majority of patients, surgery. Simple resection of the diverticulum and suture of the breach in double layer is the elective operation of non-complicated diverticulum or with an inflamed projection from the cecal wall ("usual type"). Segmental resection of colon or "right hemicolectomy" is recommended when a precise diagnosis is not possible and in complicated diverticula ("hidden variant"). On the basis of personal experience it is underlined that diagnosis is rarely made preoperatively since the clinical picture suggests an acute appendicitis. If there are some doubts for appendicitis, a incidental tumor or possible perforated diverticulum of the cecum should be considered and urgent surgery is mandatory.     

Tunable approximations to control time-to-solution in an HPC molecular docking Mini-App

The Journal of Supercomputing - The drug discovery process involves several tasks to be performed in vivo, in vitro and in silico. Molecular docking is a task typically performed in silico. It aims...     

Correlations Between Precursor Molecular Weight and Dynamic Mechanical Properties of Polyborosiloxane (PBS)

It is possible to tailor the dynamic response of polyborosiloxanes (PBS) based on picking the right molecular weight of a precursor. The molecular weight of hydroxy-terminated polydimethylsiloxane (PDMS) defines the shear-stiffening performance of PBS due to straightforward condensation reaction between hydroxy end groups of PDMS and boric acid. Introduced borono groups behave as stickers, hence, are prone to supramolecular interactions. New correlations are discovered for five PBS synthesized from hydroxy-terminated PDMS with different molecular weights. Si─O─B infrared band intensities for all PBS follow the same trend with molecular weight as the number of PDMS hydroxy groups which confirms the full completion of the reaction. After synthesis, the molecular weight of PBSs remained almost the same, which indicates the absence of significant chain scissoring, polymerization, or crosslinking. During the rheological analysis, it is found that crossover point modulus follows the same trend as the number of PDMS hydroxy groups and Si─O─B band intensities. PBS demonstrates a linear increase in peak forces with molecular weight during the drop weight impact test. The low molecular weight of a precursor, hence, a high number of stickers is a primary requirement for effective protection against low-velocity impact.     

Improving the nutritional and phytochemical compounds of a plant-based milk of sapucaia nut cake using block freeze concentration

The nutrient profile and the phytochemical composition of the sapucaia nut cake milk (SNCM) were evaluated after applying five consecutive stages of block freeze concentration (C1, C2, C3, C4 and C5). The profile of phenolic compounds by LC-ESI-MS/MS and the antioxidant activity (ABTS and FRAP) of SNCM were also determined. The freeze concentration increased proteins, lipids, carbohydrates, ash, soluble solids (°Brix) and total phenolic compounds (TPC) in all stages and in the ice fractions obtained from C1, C2 and C3 stages. The antioxidant activity (ABTS) in C3, C4 and C5 fractions was highly significant (P < 0.05). The antioxidant activity (FRAP) and the phenolic compounds (gallic, vanillic, ferulic, sinapic and salicylic acids, catechin, taxifolin and sinapaldehyde) increased significantly (P < 0.05) for all five fractions. The freeze concentration was successfully used for enriching the SNCM, generating a promising ingredient for the food industry.     

Electrical conduction mechanism in conjugated polymers studied using Flicker noise spectroscopy

We have performed detailed analysis of the fluctuations of the electrical current in electrochemically deposited conductive polymers (CP) using as example polyaniline and poly(3-methylthiophene). These heterogeneous and disordered materials cannot be analyzed in terms of classical conduction mechanisms (like Schottky or Poole-Frenkel emission). Instead, the electrical transport in CPs is to be considered as a stochastic process with large component of noise. We have been able to distinguish several modes of the conduction process in CPs by applying Flicker noise spectroscopy. Thus, we have established that the transport of charge carriers in highly doped CPs is much less correlated than in non-doped ones at the same electric field strength. While applied electric field increases, correlations become lower in a sequence of elementary events contributing to the conductivity of CP. Apparently, the change in the correlation length corresponds to changing mechanism of the electrical conduction. The lower correlation in highly doped sample can be attributed to various factors including change in CP conformation, enhancement in interchain charge transfer and generation of polaron lattice.     

Biodegradable elastomers based on ABA triblocks: influence of end‐block crystallinity on elastomeric character

ABA triblock copolymers, based on biodegradable monomers, namely ε‐caprolactone (CL) and L ‐lactide (LLA), were synthesized and studied. The end‐blocks were mostly poly(L ‐lactide) while the middle segments were a random copolymer of PCL and PLLA. Synthesis of these copolymers was performed by varying the end‐block segment length while retaining a fixed middle‐block segment length and vice versa. Nuclear magnetic resonance studies confirmed the designed structure of the copolymers and their thermal properties were studied with differential scanning calorimetry. Mechanical and thermomechanical properties were determined with an Instron tester and by dynamic mechanical analysis, respectively. The elastomeric character of the copolymers was verified by cyclic test as well as by creep and recovery measurements. Changes made to the middle‐ and end‐block segment lengths had a significant influence on the mechanical properties of the copolymers, especially their extendibility and recoverability. An increase in the crystallinity of the end‐blocks in the copolymers caused a drop in their elastomeric character. In cyclic testing, under conditions of 50% and 150% strain, copolymers with low end‐block crystallinity could recover more than 85% whereas copolymers with high crystallinity showed reduced recovery values as low as 60%. Copyright © 2011 Society of Chemical Industry     

Photocatalytic coatings for building industry: study of 1 year of activity in the NO x degradation

Nitrogen oxides (NO _x ) play a key role in the atmospheric reactions that create ground-level ozone and acid rain. The exploitation of building coatings acting as catalysts for NO _x degradation under the effect of solar radiation represents a feasible way of wide applicability to lower NO _x concentration in air. A crucial issue for the practical application of photocatalytic coatings is the actual lifetime of the active material. To investigate this aspect, two paints and two plasters (silicate and siloxane resins based) commercially available were formulated with 2% TiO₂ Aeroxide P25 and tested in the photocatalytic removal of NO _x in air. The results collected over 1 year show how the photoactivity lifetime of these products always decreases with their curing age, being strictly correlated to the formulation of the materials.