Turbo-Coded Adaptive Modulation Versus Space-Time Trellis Codes for Transmission over Dispersive Channels

Decision feedback equalizer (DFE)-aided turbocoded wideband adaptive quadrature amplitude modulation (AQAM) is proposed, which is capable of combating the temporal channel quality variation of fading channels. A procedure is suggested for determining the AQAM switching thresholds and the specific turbo-coding rates capable of maintaining the target bit-error rate while aiming for achieving a highly effective bits per symbol throughput. As a design alternative, we also employ multiple-input/multiple-output DFE-aided space–time trellis codes, which benefit from transmit diversity and hence reduce the temporal channel quality fluctuations. The performance of both systems is characterized and compared when communicating over the COST 207 typical urban wideband fading channel. It was found that the turbo-coded AQAM scheme outperforms the two-transmitter space–time trellis coded system employing two receivers; although, its performance is inferior to the space–time trellis coded arrangement employing three receivers. Index Terms—Coded adaptive modulation, dispersive channels, space–time trellis codes

Whole Exome Sequencing in Alzheimer’s Disease and Frontotemporal Lobar Degeneration

Dementia is a disorder characterized by cognitive impairment and/or behavioral changes that interfere with ability of daily functioning, with Alzheimer’s disease (AD) as the most common form of dementia, and frontotemporal dementia (FTD) as the second most common before age of 65. My thesis focuses on the genetics of these two types of dementia. Using whole exome sequencing (WES), we have attempted to identify the underlying genetics defects in patients with AD and FTD. WES is a technique that investigates genetic information in protein coding regions of DNA. We have identified several mutations in two known AD causing genes (PSEN1 and PSEN2) and a potential new risk factor in EIF2AK3 gene in a few patients with AD. In a subset of FTD patients, we have identified the underlying mutations in VCP and TUBA4A genes. At last, using WES and proteomics we have identified a new mutation in PRKAR1B gene in a rare type of dementia with parkinsonian symptoms. The identification of new genetic defects give us insights in the disease mechanisms involved in AD and FTD. This is important for the development of medication for dementia in the future

Toward sustainable express deliveries for online shopping: reusing packaging materials through reverse logistics

The COVID-19 pandemic has led to an increase in online purchases, which has inevitably raised the demand for express delivery packaging materials (EDPMs). This study proposes a reverse logistics reuse framework that extends the EDPM life cycle by drawing on insights and conclusions from a review of the literature on supply chain management and materials science to achieve a sustainable e-commerce system. A key benefit of reverse logistics is its effectiveness in exploiting opportunities for resource reuse, which is preferred to recycling. By extending service life through resource optimization, recycling, and recovery processes, the novel reuse framework based on reverse logistics can be implemented with minimal changes to existing forward logistics systems, potentially leading to more sustainable online shopping. This study proposes a novel combination of reusable packaging materials and reverse logistics as a viable and more environmentally friendly practice, in line with circular economy goals

Ursolic acid inhibits the initiation, progression of prostate cancer and prolongs the survival of TRAMP mice by modulating pro-inflammatory pathways

10.1371/journal.pone.0032476PLoS ONE73

Genetic screening in early-onset Alzheimer's disease identified three novel presenilin mutations

Mutations in presenilin 1 (PSEN1), presenilin 2 (PSEN2), and amyloid precursor protein (APP) are major genetic causes of early-onset Alzheimer's disease (EOAD). Clinical heterogeneity is frequently observed in patients with PSEN1 and PSEN2 mutations. Using whole exome sequencing, we screened a Dutch cohort of 68 patients with EOAD for rare variants in Mendelian Alzheimer's disease, frontotemporal dementia, and prion disease genes. We identified 3 PSEN1 and 2 PSEN2 variants. Three variants, 1 in PSEN1 (p.H21Profs*2) and both PSEN2 (p.A415S and p.M174I), were novel and absent in control exomes. These novel variants can be classified as probable pathogenic, except for PSEN1 (p.H21Profs*2) in which the pathogenicity is uncertain. The initial clinical symptoms between mutation carriers varied from behavioral problems to memory impairment. Our findings extend the mutation spectrum of EOAD and underline the clinical heterogeneity among PSEN1 and PSEN2 mutation carriers. Screening for Alzheimer's disease–causing genes is indicated in presenile dementia with an overlapping clinical diagnosis

First detection of Babesia sp. in Bornean sun bear (Helarctos malayanus euryspilus Horsfield) in Sabah, Malaysia

The Bornean sun bear, a subspecies of the endangered Malayan sun bear, resides only on Borneo Island and little is known about diseases or parasites that may impact their health. In 2019, blood and ticks were collected from 46 captive bears held at the Bornean Sun Bear Conservation Centre in Sabah, Malaysia during annual health examinations in response to previous blood smear analysis that revealed presumptive haemoparasites in more than half the resident bears. Polymerase chain reaction detected a unique Babesia sp. in one of the bears. Disease surveillance of mosquitoes trapped along the outer perimeter of the bears’ outdoor enclosure did not reveal any malaria parasites. This research marks the first documented case in Bornean sun bears of both a Babesia sp. and the Ixodes tick Haemaphysalis nr koningsbergeri. More research on incriminating the vector and the effects of Babesia infection on the health of Bornean sun bears is needed. Due to the zoonotic nature of babesiosis, mitigative actions should be taken to protect any humans that work with or come into close contact with these captive bears or their enclosures

Conserving and Gapless Approximations for an Inhomogeneous Bose Gas at Finite Temperatures

We derive and discuss the equations of motion for the condensate and its fluctuations for a dilute, weakly interacting Bose gas in an external potential within the self--consistent Hartree--Fock--Bogoliubov (HFB) approximation. Account is taken of the depletion of the condensate and the anomalous Bose correlations, which are important at finite temperatures. We give a critical analysis of the self-consistent HFB approximation in terms of the Hohenberg--Martin classification of approximations (conserving vs gapless) and point out that the Popov approximation to the full HFB gives a gapless single-particle spectrum at all temperatures. The Beliaev second-order approximation is discussed as the spectrum generated by functional differentiation of the HFB single--particle Green's function. We emphasize that the problem of determining the excitation spectrum of a Bose-condensed gas (homogeneous or inhomogeneous) is difficult because of the need to satisfy several different constraints.Comment: plain tex, 19 page

Visiting urban green space as a climate-change adaptation strategy: Exploring push factors in a push–pull framework

Urban green space (UGS) offers users multiple ecosystem services and amenities. This study investigated whether residents used UGS visitation in summer as a sustainable measure to tackle hot weather and associated climate-change impacts in humid-subtropical Hong Kong. Attributes of the indoor residential environment, seldom examined in park-visitation studies, were evaluated as push factors to visit UGS through a push–pull theoretical framework. A questionnaire survey of 483 respondents targeted urban park users. The results indicated that UGS visit frequency and stay duration were relatively low in hot summer. Ordinal multiple regression showed that indoor living conditions, residence location, living routine, and habit and personal health impacts were significantly correlated with UGS visits. Interdependence between push and pull factors was detected, demonstrating that intrinsic UGS environmental conditions could constrain UGS visits despite the motivations of push factors. The results indicated the need to improve the microclimate-regulating function in UGS. It could be achieved mainly by optimizing the nature-based design to promote UGS as an adaptive measure to combat the thermal stress brought by climate change. The findings yielded hints to shape visiting habits and suggestions to improve UGS management

Stress corrosion cracking in Al-Zn-Mg-Cu aluminum alloys in saline environments

Copyright 2013 ASM International. This paper was published in Metallurgical and Materials Transactions A, 44A(3), 1230 - 1253, and is made available as an electronic reprint with the permission of ASM International. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplications of any material in this paper for a fee or for commercial purposes, or modification of the content of this paper are prohibited.Stress corrosion cracking of Al-Zn-Mg-Cu (AA7xxx) aluminum alloys exposed to saline environments at temperatures ranging from 293 K to 353 K (20 °C to 80 °C) has been reviewed with particular attention to the influences of alloy composition and temper, and bulk and local environmental conditions. Stress corrosion crack (SCC) growth rates at room temperature for peak- and over-aged tempers in saline environments are minimized for Al-Zn-Mg-Cu alloys containing less than ~8 wt pct Zn when Zn/Mg ratios are ranging from 2 to 3, excess magnesium levels are less than 1 wt pct, and copper content is either less than ~0.2 wt pct or ranging from 1.3 to 2 wt pct. A minimum chloride ion concentration of ~0.01 M is required for crack growth rates to exceed those in distilled water, which insures that the local solution pH in crack-tip regions can be maintained at less than 4. Crack growth rates in saline solution without other additions gradually increase with bulk chloride ion concentrations up to around 0.6 M NaCl, whereas in solutions with sufficiently low dichromate (or chromate), inhibitor additions are insensitive to the bulk chloride concentration and are typically at least double those observed without the additions. DCB specimens, fatigue pre-cracked in air before immersion in a saline environment, show an initial period with no detectible crack growth, followed by crack growth at the distilled water rate, and then transition to a higher crack growth rate typical of region 2 crack growth in the saline environment. Time spent in each stage depends on the type of pre-crack (“pop-in” vs fatigue), applied stress intensity factor, alloy chemistry, bulk environment, and, if applied, the external polarization. Apparent activation energies (E a) for SCC growth in Al-Zn-Mg-Cu alloys exposed to 0.6 M NaCl over the temperatures ranging from 293 K to 353 K (20 °C to 80 °C) for under-, peak-, and over-aged low-copper-containing alloys (~0.8 wt pct), they are typically ranging from 20 to 40 kJ/mol for under- and peak-aged alloys, and based on limited data, around 85 kJ/mol for over-aged tempers. This means that crack propagation in saline environments is most likely to occur by a hydrogen-related process for low-copper-containing Al-Zn-Mg-Cu alloys in under-, peak- and over-aged tempers, and for high-copper alloys in under- and peak-aged tempers. For over-aged high-copper-containing alloys, cracking is most probably under anodic dissolution control. Future stress corrosion studies should focus on understanding the factors that control crack initiation, and insuring that the next generation of higher performance Al-Zn-Mg-Cu alloys has similar longer crack initiation times and crack propagation rates to those of the incumbent alloys in an over-aged condition where crack rates are less than 1 mm/month at a high stress intensity factor