Internet Predictions

More than a dozen leading experts give their opinions on where the Internet is headed and where it will be in the next decade in terms of technology, policy, and applications. They cover topics ranging from the Internet of Things to climate change to the digital storage of the future.     

Clinical events in coronary patients who report low distress: Adverse effect of repressive coping.

Objective: Coronary artery disease (CAD) patients who report low distress are considered to be at low psychological risk for clinical events. However, patients with a repressive coping style may fail to detect and report signals of emotional distress. The authors hypothesized that repressive CAD patients are at risk for clinical events, despite low self-rated distress. Design: This was a prospective 5- to 10-year follow-up study, with a mean follow-up of 6.6 years. At baseline, 731 CAD patients filled out Trait-Anxiety (distress), Marlowe-Crowne (defensiveness), and Type D scales; 159 patients were classified as "repressive," 360 as "nonrepressive," and 212 as "Type D." Main Outcome Measures: The primary endpoint was a composite of total mortality or myocardial infarction (MI); the secondary endpoint was cardiac mortality/MI. Results: No patients were lost to follow-up; 91 patients had a clinical event (including 35 cardiac death and 32 MI). Repressive patients reported low levels of anxiety, anger and depression at baseline, but were at increased risk for death/MI (21/159 = 13%) compared with nonrepressive patients (22/360 = 6%), p = .009. Poor systolic function, poor exercise tolerance, 3-vessel disease, index MI and Type-D personality--but not depression, anxiety or anger--also independently predicted clinical events. After controlling for these variables, repressive patients still had a twofold increased risk of death/MI, OR = 2.17, 95% CI = 1.10-4.08, p = .025). These findings were replicated for cardiac mortality/MI. Conclusion: CAD patients who use a repressive coping style are at increased risk for clinical events, despite their claims of low emotional distress. This phenomenon may cause an underestimation of the effect of stress on the heart. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hydrolysis degree,peptide profile and phenylalanine removal from whey protein concentrate hydrolysates obtained by various proteases

The action of various proteases was tested for preparing whey protein concentrate (WPC) hydrolysates with high degree of hydrolysis (DH), appropriate peptide profiles and reduced phenylalanine (Phe) content. The peptide profile analysis included the fractionation of hydrolysates by size‐exclusion HPLC. The rapid correct fraction area method was used to quantify the components of the chromatographic fractions. Activated carbon (AC) was used to remove Phe, and its efficiency was evaluated by measuring the amount of Phe by second‐derivative spectrophotometry. The results showed that the DH of WPC hydrolysates increased and that the protease from Aspergillus oryzae yielded the highest DH value. This protease also produced the best peptide profile, that is, the highest di‐ and tripeptide content (16.14%), the highest amounts of free amino acids (18.43%) and the lowest amount of large peptides (18.76%). The proteases from both A. oryzae and Bacillus subtilis produced the highest Phe removals (79.0 and 77.8%, respectively).     

Practical perfect hashing in nearly optimal space

A hash function is a mapping from a key universe U   to a range of integers, i.e., h:U?{0,1,…,m−1}$h:U?\{\mathrm{0,1},\dots ,m-1\}$, where m is the range's size. A perfect hash function   for some set S⊆U$S\subseteq U$ is a hash function that is one-to-one on S  , where m≥|S|$m\ge \left|S\right|$. A minimal perfect hash function   for some set S⊆U$S\subseteq U$ is a perfect hash function with a range of minimum size, i.e., m=|S|$m=\left|S\right|$. This paper presents a construction for (minimal) perfect hash functions that combines theoretical analysis, practical performance, expected linear construction time and nearly optimal space consumption for the data structure. For n keys and m=n   the space consumption ranges from 2.62n+o(n)$2.62n+o(n)$ to 3.3n+o(n)$3.3n+o(n)$ bits, and for m=1.23n$m=1.23n$ it ranges from 1.95n+o(n)$1.95n+o(n)$ to 2.7n+o(n)$2.7n+o(n)$ bits. This is within a small constant factor from the theoretical lower bounds of 1.44n$1.44n$ bits for m=n   and 0.89n$0.89n$ bits for m=1.23n$m=1.23n$. We combine several theoretical results into a practical solution that has turned perfect hashing into a very compact data structure to solve the membership problem when the key set S is static and known in advance. By taking into account the memory hierarchy we can construct (minimal) perfect hash functions for over a billion keys in 46 min using a commodity PC. An open source implementation of the algorithms is available at http://cmph.sf.net under the GNU Lesser General Public License (LGPL).     

Surface analysis of oligothiophene films using HREELS: molecular orientation effects

The surface of evaporated films of α-oligothiophenes—quaterthiophene (4T), quinquethiophene (5T) and sexithiophene (6T)—was studied by high-resolution electron energy loss spectroscopy (HREELS), extending the common vibrational domain of energy loss to electronic excitation and secondary emission. Vibrational spectra show that the molecular orientation is not the same on graphite and gold substrates. HREELS results corroborate those obtained by reflection–absorption infrared spectroscopy (RAIRS), confirming that graphite substrates induce films where molecules lie flat on the surface, whereas gold substrates generate a molecular orientation close to perpendicularity. Using these two differently oriented samples, we demonstrate the existence of two relaxation channels for the electron surface interaction: electronic excitation and ionisation. HREELS spectra recorded with incident electron energy between 2 and 7 eV reveal that secondary electron emission originating from ionisations is always more efficient for escape directions perpendicular to the plane of the molecule. This is here associated with the π orbital origin of this emission. Copyright © 2000 John Wiley & Sons, Ltd.     

Multifunctional Characteristics of Glass Fiber-Reinforced Epoxy Polymer Composites with Multiwalled Carbon Nanotube Buckypaper Interlayer

In this work, multiwalled carbon nanotube buckypaper (MWCNT-BP) was inserted at the middle-plane of glass fiber/epoxy resin prepregs to obtain three-phase nanostructured composite. Preliminary tests conducted by differential scanning calorimetry and thermogravimetric analyses (TGA) revealed that the proposed curing cycle to prepare the laminates in a hot compression-molding machine was appropriated. The mechanical properties of the BP-based composite studied by short beam shear and compression shear tests presented no improvements compared to the base laminate. On the other hand, the thermal properties of the nanostructured composite improved as demonstrated by dynamical mechanical analyses and TGA. Besides, the reflectivity results revealed an average value of −12.2 dB in the X-band with a maximum attenuation of 99.4% of the incident wave at 9.5 GHz. The improvements in both thermal and electromagnetic properties demonstrate the potential for both structural and multifunctional applications of the obtained BP-composite. POLYM. ENG. SCI., 60:740–751, 2020. © 2020 Society of Plastics Engineers     

A hydrostatic/non-hydrostatic grid-switching strategy for computing high-frequency,high wave number motions embedded in geophysical flows

Hydrostatic and non-hydrostatic models were used to simulate the generation of internal surges and associated soliton-like trailing waves from the non-linear steepening of low-frequency basin-scale waves. Results confirmed that the process cannot be modelled using the hydrostatic approximation. A grid-switching strategy was developed to reduce the simulation run-time of the non-hydrostatic model; a low-resolution grid using a hydrostatic computation of the flow field is dynamically switched to a high-resolution grid in the region of propagation of the leading internal surge, using a non-hydrostatic computation of the flow field. The strategy takes advantage of the small time scale required for non-hydrostatic effects to become important such that a high-resolution grid is invoked only when and where these effects become large. Run-time reduction, conservation of the interpolation scheme involved in the grid switching and strategies for field scale studies were addressed. In relation to the laboratory experiments, the grid-switching strategy predicted the phase speed and the amplitude of the leading internal surge similarly to the uniform-grid models, however, the trailing soliton-like waves lost some of their signature. All non-hydrostatic models predicted the features of the energy flux path between low- and high-frequency waves.