KENTRACK 4.0: A RAILWAY TRACKBED STRUCTURAL DESIGN PROGRAM

The KENTRACK program is a finite element based railway trackbed structural design program that can be utilized to analyze trackbeds having various combinations of all-granular and asphalt-bound layered support. It is applicable for calculating compressive stresses at the top of subgrade, indicative of potential long-term trackbed settlement failure. Furthermore, for trackbeds containing asphalt layer, it is applicable for calculating tensile strains at the bottom of the asphalt layer, indicative of potential fatigue cracking. The program was recently expanded to include both English and international units. A procedure has been incorporated to provide a path to save results in a text formation in post-Windows XP operating systems. More importantly, properties of performance graded (PG) asphalt binders and the Witczak E* predictive model have been incorporated in the 4.0 Version of the program. Component layers of typical trackbed support systems are analyzed while predicting the significance of layer thicknesses and material properties on design and performance. The effect of various material parameters and loading magnitudes on trackbed design and evaluation, as determined and predicted by the computer program, are presented. Variances in subgrade modulus and axle loads and the incorporation of a layer of asphalt within the track structure have significant effects on subgrade vertical compressive stresses and predicted trackbed service lives. The parameter assessments are presented and evaluated using sensitivity analysis. Recommendations for future research are suggested

Predictive value of whole-brain CT perfusion combined with ABCD3 score for short-term secondary cerebral infarction after TIA

ObjectiveTo investigate the predictive value of Whole Brain CT Perfusion (WB-CTP) combined with the ABCD3 score in patients with transient ischemic attack (TIA).MethodsA total of 336 TIA patients with TIA underwent WB-CTP and ABCD3 score assessment within 48 h of admission. Spearman correlation test was performed to analyze the relationship between the degree of vascular stenosis, relative perfusion values, and ABCD3 score. Logistic regression analysis was used to identify independent risk factors for secondary cerebral infarction. Receiver operating characteristic (ROC) curves were generated to evaluate the predictive value of relative cerebral blood flow (rCBF), degree of vascular stenosis, ABCD3 score, and the WB-CTP-ABCD3 combined model for secondary cerebral infarction after TIA. Calibration curves and H-L tests were used to evaluate the predictive efficacy of the model.ResultsAmong the 336 TIA patients, 143 showed abnormal perfusion areas and 146 had responsible vessel stenosis. The degree of vascular stenosis, relative time-to-maximum (rTmax), and relative mean transit time (rMTT) were positively correlated with the ABCD3 score, while rCBF and relative cerebral blood volume (rCBV) were negatively correlated with the ABCD3 score. ROC curve analysis identified a cutoff value of 0.8205 for rCBF, with a sensitivity of 84.10% and specificity of 58.10% for distinguishing the cerebral infarction group from the non-cerebral infarction group. Furthermore, rCBF ≤ 0.8205, degree of vascular stenosis, and ABCD3 score > 6 were identified as independent risk factors for secondary cerebral infarction in TIA patients within 90 days in TIA patients. The AUC of the WB-CTP-ABCD3 combined model for predicting secondary cerebral infarction within 90 days was 0.836. The model risk was assessed by plotting calibration curves. The value of p for the H-L goodness of fit test was 0.366 (p > 0.05), which indicated that the difference between the obtained model and the perfect model were statistically insignificant.ConclusionThe combined model of WB-CTP-ABCD3 shows promise as a valuable method for predicting secondary cerebral infarction within 90 days following TIA

High-resolution vessel wall imaging for quantitatively and qualitatively evaluating in-stent stenosis of intracranial aneurysms

BackgroundIt is critical to accurately and noninvasively evaluate the stented parent artery of intracranial aneurysms (IAs) with endovascular treatment.ObjectiveTo investigate high-resolution vessel wall imaging (HR-VWI) for quantitative and qualitative evaluation of in-stent stenosis (ISS) in IAs treated with stent placement (SP).MethodsFifty-five patients (58 aneurysms) underwent HR-VWI, contrast-enhanced (CE)-HR-VWI, CE-MR angiography (MRA), time-of-flight (TOF)-MRA, and digital subtraction angiography (DSA) six months after SP, and the reliability of quantitative stent lumen measurements was evaluated by intraclass correlation coefficient (ICC) analysis. Agreement and correlation of quantitative evaluation were estimated by comparing the four MR imaging modalities with DSA. The diagnostic performance for >0%, ≥25%, and ≥50% of ISS degrees and overall diagnostic accuracy for the ISS degrees of the four MR imaging modalities were calculated to qualitative evaluation.ResultsThe reliability of CE-HR-VWI and HR-VWI for ISS quantitative measurements was excellent (ICC 0.955–0.989). The agreement and correlation of CE-HR-VWI, HR-VWI versus DSA for ISS quantitative measurements were better than those of CE-MRA and TOF-MRA (p < 0.05). The diagnostic performance for distinguishing the degree of ISS >0%, ≥25%, and ≥50% by CE-HR-VWI and HR-VWI was superior to CE-MRA and TOF-MRA, and their overall diagnostic accuracy was 96.55 and 94.83%, respectively. HR-VWI and CE-HR-VWI were not statistically significant in the quantitative and qualitative evaluation of ISS performance (p > 0.05).ConclusionHR-VWI and CE-HR-VWI have similar performance and value in the quantitative and qualitative evaluation of ISS, and HR-VWI without contrast media could be used as an ideal long-term follow-up approach after SP treatment for IAs

Kwas zoledronowy stosowany przez dwa lata u Chinek z osteoporozą pomenopauzalną zwiększa gęstość mineralną tkanki kostnej i poprawia jakość życia związaną ze stanem zdrowia

Introduction: Osteoporosis is characterised by decreased bone mass and weakened bones, with an increased risk of fractures. Osteoporotic fracture, the most serious complication of osteoporosis, is related not only to lower bone mineral density (BMD), but also falls. Osteoporosis and fractures are associated with a decreased health-related quality of life (HRQL). Zoledronic acid (ZOL) is an intravenous once-yearly bisphosphonate that has been shown to be effective and safe in improving BMD and reducing fracture risk in controlled clinical trials.Material and methods: In this self-controlled, prospective trial, 220 postmenopausal women with osteoporosis (mean age 67 years) received a single infusion of ZOL 5 mg at baseline and month 12. BMD, HRQL and Fall Index (FI) were measured at baseline, and months 12 and 24 (before each use of ZOL). The main outcome measures were the changes in lumbar spine and hip BMD and the changes in HRQL, the Short Form-36 questionnaire (SF-36). Additional comparisons were based on the FI. LSD multiple comparisons were used in the comparisons of BMD, SF-36 domain scores and FI.Results: The patients had significantly higher L1-4, total hip, femoral neck and trochanter BMD (P < 0.05) with improved HRQL (P < 0.05) over two years of treatment of once-yearly ZOL 5mg. FI was reduced (P < 0.05) with oral daily elemental calcium and vitamin D in the treatment course.Conclusions: ZOL improves BMD and HRQL, especially in the physical aspects, over two years of treatment in women with postmenopausal osteoporosis, and can help improve balance ability. (Endokrynol Pol 2014; 65 (2): 96–104)Wstęp: Osteoporoza to schorzenie cechujące się obniżeniem masy kostnej i wytrzymałości mechanicznej kości z towarzyszącym zwiększeniem ryzyka złamań. Złamania osteoporotyczne, będące najpoważniejszym powikłaniem osteoporozy, wiążą się nie tylko z obniżoną gęstością mineralną tkanki kostnej (BMD, bone mineral density) ale też z upadkami. Z osteoporozą i złamaniami wiąże się obniżenie jakości życia związanej ze stanem zdrowia (HRQoL, health-related quality of life). Kwas zoledronowy (ZOL) to bisfosfonian w postaci dożylnej przeznaczony do podawania raz w roku, w przypadku którego w badaniach klinicznych z grupą kontrolną wykazano skuteczność i bezpieczeństwo w zwiększaniu BMD i zmniejszaniu ryzyka złamań.Materiał i metody: Autorzy przeprowadzili samodzielnie kontrolowane, prospektywne badanie z udziałem 220 znajdujących się w wieku pomenopauzalnym kobiet z osteoporozą (średnia wieku 67 lat), które otrzymały jednorazowo roztwór ZOL w dawce 5 mg na początku badania i 12 miesięcy później. Na początku badania, w 12. miesiącu i w 24. miesiącu badania (za każdym razem przed podaniem ZOL) oznaczano BMD, HRQoL i wskaźnik upadków (FI, fall index). Główne punkty końcowe obejmowały zmiany BMD w odcinku lędźwiowym kręgosłupa i BMD w okolicy biodra, a także zmiany HRQoL w kwestionariuszu SF-36. Dodatkowe porównania będą oparte na FI. W porównaniach wartości BMD, liczby punktów w poszczególnych domenach kwestionariusza SF-36 i wartości FI zastosowano metodę wielokrotnych porównań najmniejszej istotnej różnicy.Wyniki: U pacjentek stwierdzono znamiennie większe wartości BMD na poziomie L1–4, BMD w całkowitym obszarze biodra, BMD w obrębie szyjki kości udowej oraz BMD w obrębie krętarza (p < 0,05) oraz znamienną poprawę HRQoL (p < 0,05) w okresie 2 lat leczenia podawanym raz w roku ZOL w dawce 5 mg. Stwierdzono też zmniejszenie FI (p < 0,05) dzięki codziennemu przyjmowaniu wapnia i witaminy D w okresie leczenia.Wnioski: Stosowanie ZOL prowadzi do poprawy BMD i HRQoL, zwłaszcza w aspekcie fizycznym, w okresie 2 lat stosowania u kobiet z osteoporozą pomenopauzalną, i może przyczyniać się do poprawy zdolności utrzymania równowagi. (Endokrynol Pol 2014; 65 (2): 96–104

Immobilization of Interfacial Activated Candida rugosa Lipase Onto Magnetic Chitosan Using Dialdehyde Cellulose as Cross-Linking Agent

Candidarugosa lipase (CRL) was activated with surfactants (sodium dodecyl sulfate [SDS]) and covalently immobilized onto a nanocomposite (Fe3O4-CS-DAC) fabricated by combining magnetic nanoparticles Fe3O4 with chitosan (CS) using polysaccharide macromolecule dialdehyde cellulose (DAC) as the cross-linking agent. Fourier transform infrared spectroscopy, transmission electron microscope, thermogravimetric analysis, and X-ray diffraction characterizations confirmed that the organic–inorganic nanocomposite support modified by DAC was successfully prepared. Enzymology experiments confirmed that high enzyme loading (60.9 mg/g) and 1.7 times specific enzyme activity could be obtained under the optimal immobilization conditions. The stability and reusability of immobilized CRL (Fe3O4-CS-DAC-SDS-CRL) were significantly improved simultaneously. Circular dichroism analysis revealed that the active conformation of immobilized CRL was maintained well. Results demonstrated that the inorganic–organic nanocomposite modified by carbohydrate polymer derivatives could be used as an ideal support for enzyme immobilization

Fecal microbiota transplantation inhibited neuroinflammation of traumatic brain injury in mice via regulating the gut–brain axis

IntroductionRecent studies have highlighted the vital role of gut microbiota in traumatic brain injury (TBI). Fecal microbiota transplantation (FMT) is an effective means of regulating the microbiota–gut–brain axis, while the beneficial effect and potential mechanisms of FMT against TBI remain unclear. Here, we elucidated the anti-neuroinflammatory effect and possible mechanism of FMT against TBI in mice via regulating the microbiota–gut–brain axis.MethodsThe TBI mouse model was established by heavy object falling impact and then treated with FMT. The neurological deficits, neuropathological change, synaptic damage, microglia activation, and neuroinflammatory cytokine production were assessed, and the intestinal pathological change and gut microbiota composition were also evaluated. Moreover, the population of Treg cells in the spleen was measured.ResultsOur results showed that FMT treatment significantly alleviated neurological deficits and neuropathological changes and improved synaptic damage by increasing the levels of the synaptic plasticity-related protein such as postsynaptic density protein 95 (PSD-95) and synapsin I in the TBI mice model. Moreover, FMT could inhibit the activation of microglia and reduce the production of the inflammatory cytokine TNF-α, alleviating the inflammatory response of TBI mice. Meanwhile, FMT treatment could attenuate intestinal histopathologic changes and gut microbiota dysbiosis and increase the Treg cell population in TBI mice.ConclusionThese findings elucidated that FMT treatment effectively suppressed the TBI-induced neuroinflammation via regulating the gut microbiota–gut–brain axis, and its mechanism was involved in the regulation of peripheral immune cells, which implied a novel strategy against TBI

Asymmetric Chiral Coupling in a Topological Resonator

Chiral light-matter interactions supported by topological edge modes at the interface of valley photonic crystals provide a robust method to implement the unidirectional spin transfer. The valley topological photonic crystals possess a pair of counterpropagating edge modes. The edge modes are robust against the sharp bend of $60^{\circ}$ and $120^{\circ}$, which can form a resonator with whispering gallery modes. Here, we demonstrate the asymmetric emission of chiral coupling from single quantum dots in a topological resonator by tuning the coupling between a quantum emitter and a resonator mode. Under a magnetic field in Faraday configuration, the exciton state from a single quantum dot splits into two exciton spin states with opposite circularly polarized emissions due to Zeeman effect. Two branches of the quantum dot emissions couple to a resonator mode in different degrees, resulting in an asymmetric chiral emission. Without the demanding of site-control of quantum emitters for chiral quantum optics, an extra degree of freedom to tune the chiral contrast with a topological resonator could be useful for the development of on-chip integrated photonic circuits.Comment: 13 pages, 4 figure

The chemistry and biological activity of the Hyacinthaceae

Covering: 1914 to 2012The Hyacinthaceae (sensu APGII), with approximately 900 species in about 70 genera, can be divided into three main subfamilies, the Hyacinthoideae, the Urgineoideae and the Ornithogaloideae, with a small fourth subfamily the Oziroëoideae, restricted to South America. The plants included in this family have long been used in traditional medicine for a wide range of medicinal applications. This, together with some significant toxicity to livestock has led to the chemical composition of many of the species being investigated. The compounds found are, for the most part, subfamily-restricted, with homoisoflavanones and spirocyclic nortriterpenoids characterising the Hyacinthoideae, bufadienolides characterising the Urgineoideae, and cardenolides and steroidal glycosides characterising the Ornithogaloideae. The phytochemical profiles of 38 genera of the Hyacinthaceae will be discussed as well as any biological activity associated with both crude extracts and compounds isolated. The Hyacinthaceae of southern Africa were last reviewed in 2000 (T. S. Pohl, N. R. Crouch and D. A. Mulholland, Curr. Org. Chem., 2000, 4, 1287-1324; ); the current contribution considers the family at a global level

Securing 5G Positioning and its Services with Privacy Preservation

Different from the global positioning system (GPS), the positioning in the fifth-generation (5G) cellular networks is measured through nearby access nodes and processed at the cloud/edge/fog devices. Owing to the availability of high-quality measurements and outsourced computation, the 5G positioning promises high precision, high reliability, wide coverage and low power consumption. The 5G positioning ecosystem relates to 5G positioning and its services. There are four main stakeholders in the ecosystem: location information service provider (LISP), location-based service provider (LBSP), user equipment (UE) with a 5G connection and the location information collaborator (LIC).Focusing on 5G positioning and its services, the present dissertation aims to investigate and resolve the problems in the area of security, privacy and integrity. (1) The security of 5G positioning is threatened by various attacks from signal jamming and counterfeiting to malicious or untrusted devices and users. For solving the security problem in 5G positioning, a framework composed of three modules is proposed to defend against jamming and collusion attacks. (2) To prevent the privacy violation in outsourced 5G positioning computation, two protocols (Pub-pos and Pri-pos) with flexible privacy selection are proposed. (3) Also in the case of outsourced 5G positioning services, we apply an integrity check method by creating a backdoor in an outsourced positioning model based on machine learning. (4) LIC facilitates the position verification by interacting with nearby UEs through distributed device-to-device (D2D) communication. However, the position of private LIC is leaked in the position verification process. To solve this problem, we propose a privacy preservation scheme implemented with the double order-preserving encryption (OPE) and a coordinate-based verification method. Experimental results show significant performance improvement. (5) LBS provision is conducted between the UE and LBSP. For privacy protection, the UE wants to hide its position information and LBSP wants to protect its database from any unauthorized access. However, it is challenging to support a variety of LBS queries and meet the low latency requirement in LBS provision based on 5G positioning, especially when both UE position privacy and LBSP data privacy should be protected at the same time. We propose two protocols, based on exact and fuzzy kNN queries, to achieve mutual privacy preservation, flexible keyword search and low latency. All the proposed schemes are evaluated with simulations or real-world datasets. The results demonstrate the improvement or the trade-off among security, privacy, integrity and overhead. It is expected that this dissertation can further advance secure and privacy-preserving 5G positioning and its services

A comprehensive study on membrane fouling by different sludge fractions of a membrane bioreactor with long solid retention time

100 p.Membrane fouling and the scarce knowledge on microorganisms' behaviour limit the industrial application of MBRs with long SRT. Moreover, the mixed liquor composition varies with inflow quality and operating conditions, the contribution of each sludge fraction to membrane fouling is changed along with different inflow quality and operating conditions. Therefore, it is necessary to investigate the influences of MLSS concentration, trans-membrane pressure and cross-flow velocity on membrane fouling to have a better understanding of the fouling behaviours in MBRs with long SRT conditions.MASTER OF ENGINEERING (CEE