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Monolayer MoNx and nano-multilayer CrN/Mo 2 N coatings were prepared by arc ion plating and characterized by X-ray diffractometry (XRD), transmission electron microscopy (TEM), friction tester and hardness tester. The results from TEM and XRD analysis showed that the crystal structure of MoNx and CrN/Mo 2 N coatings has a cubic lattice structure. The microhardness of MoNx coatings deposited at lower N 2 pressure is about 2100 HV which is higher than 1950 HV of the coatings deposited at higher N 2 pressure. The variation of friction coefficient of MoNx coatings influenced by N 2 pressure is obvious at higher N 2 pressure. The modulation period of CrN/Mo 2 N coatings is from 58.5 nm to 11.17 nm with increasing substrate rotation speed (Srs) in the range of 1–5 rpm. The maximum hardness of CrN/Mo 2 N nanomultilayer coatings, when the Srs is 7 rpm, is approximately 2950 HV. The value is 1.5 times higher than those of the MoNx monolayer coating (2000 HV). These enhancement effects in superlattice films could be attributed to the resistance to dislocation glide across interface between the MoN and CrN layers. The value of average friction coefficient of CrN/Mo 2 N nanomultilayer coatings is about 0.33 which is higher than 0.3 of MoNx coatings and lower than 0.6 of CrN. The wear rate of CrN/Mo 2 N nanomultilayer coatings is about 7 × 10−7 mm3/N·m which is obviously lower than 3.3 × 10−6 mm3/N·m of CrN coatings and higher than 1.2 × 10−7 mm3/N·m of MoNx coatings. • Monolayer MoNx and nanomultilayer CrN/Mo 2 N coatings were prepared by arc ion plating system. • The N 2 pressure exhibits great effects on the structure and properties of MoNx coatings. • The substrate rotation speed exhibits great effects on the hardness of CrN/Mo 2 N nanomultilayer coatings. [ABSTRACT FROM AUTHOR]

Aluminum foam was limited when applied as load carrying structures for its lower strength. Therefore, an effective enhancement method of aluminum foam was reported in the present study by filling of 304 stainless steel tube into a pre-perforated hole and fixed by epoxy glue. The experimental results indicate that the novel tube enhanced foam (with equivalent density of foam) can doubled the specific compressive strength and energy absorption of that of aluminum foam, and even larger than that of the sum of tube and foam which were tested separately. The coupling strengthening mechanisms are suggested to be the instability limitation of steel tube due to the lateral supports (external and internal) supplied by aluminum foam. [ABSTRACT FROM AUTHOR]

Agricultural soils are strong sources of the potent greenhouse gas N 2 O but soil N 2 O emissions and its microbial mechanism in greenhouse field, especially ammonia-oxidizing microorganisms are unclear. We characterized a potential response in soil N 2 O production and its influencing factors, such as soil temperature, moisture, pH, and inorganic nitrogen to different irrigation methods named drip irrigation (DI), subsurface irrigation (SI) and furrow irrigation (FI) in a long-term irrigation field in greenhouse. The abundance and metabolic activity of ammonia oxidizing archaea (AOA) and bacteria (AOB) in greenhouse soils were also investigated using amoA gene as a molecular biomarker by quantitative PCR and 13 CO 2 -DNA-stable isotope probing (SIP) methods. Results showed that N 2 O flux peaks would obviously occur within 1–8 days after each irrigation. The soil N 2 O flux in FI treatment was significantly higher than that in DI and SI treatments ( P <  0.05). Correlation analysis between soil N 2 O flux and its influencing factors indicated that soil moisture and nitrate nitrogen were substantially affecting soil N 2 O emissions compared with soil temperature, pH and ammonium nitrogen. The copy numbers of AOA amoA gene in FI treatment were significantly higher than those in DI and SI treatments ( P <  0.05), while there is no significant difference of AOB amoA gene among the three treatments. Also, the copy numbers of AOA amoA gene were significantly higher than those of AOB amoA gene. The 13 CO 2 -DNA-SIP and phylogenetic tree results indicated only AOB dominantly involved in Nitrosospira genera was active during the nitrification process in the three irrigation methods. Our findings provided direct evidence that drip irrigation and subsurface irrigation could effectively reduce soil N 2 O emissions in greenhouse. AOA was dominant in abundance, while AOB played a key role in microbial community under the conditions of this experiment. Future characterization of the mechanisms for ammonia oxidation requires deeper studies in the greenhouse field. [ABSTRACT FROM AUTHOR]

The effects of massive laser shock peening (LSP) treatment with different coverage layers on residual stress, pitting morphologies in a standard corrosive solution and electrochemical corrosion resistance of AISI 4145 steel were investigated by pitting corrosion test, potentiodynamic polarisation test, and SEM observations. Results showed massive LSP treatment can effectively cause an obvious improvement of pitting corrosion resistance of AISI 4145 steel, and increased coverage layer can also gradually improve its corrosion resistance. Massive LSP treatment with multiple layers was shown to influence pitting corrosion behaviour in a standard corrosive solution. [ABSTRACT FROM AUTHOR]

CrN/Mo 2 N films were deposited by multi-cathodic arc ion plating on Si (100), 304 stainless steel and cemented carbide substrates with various bilayer periods (10–105 nm). X-ray diffraction analysis revealed a face-centered-cubic structure of CrN and Mo 2 N sublayers. Rutherford backscattering spectrometry (RBS) was used to probe the elemental composition and their depth profiling. The multilayer structures exhibited characteristic oscillating RBS spectra. The nanohardness slightly increased at larger bilayer periods and the highest value of 29 GPa was obtained at the bilayer period of 105 nm. A correlation was realized among compressive residual stress, critical load, and nanohardness. The highest critical load L c2 of 65–70 N was found for the coatings on cemented carbide substrates with the minimal bilayer period of 12 nm. The coefficients of friction and wear rates of the coatings were in the range of 0.29–0.35 and (6–8) × 10 − 7 mm 3 /N·m, respectively. [ABSTRACT FROM AUTHOR]

Purpose/objective(s): A novel therapeutic machine that combines PET, fan beam kVCT and linear accelerator to support real-time PET-guided treatment, termed biology-guided radiotherapy (BgRT). This study reports the positioning accuracy, image quality, and dose commissioning of the kVCT imaging system of the first clinical BgRT machine at our institute.Materials/methods: The helical fan-beam kVCT subsystem consists of an X-ray tube with a voltage of 120kV and a 16-row GOS Ceramic Scintillator detector. The gantry rotation speed is 60 rpm. The tube currents are 45, 67, 133mA for 0.5 pitch; 100, 150, and 300mA for 0.5 pitch; 267 and 400mA for 1.333 pitch. The image slice thickness is 1.25mm with a field of view of 500mm and a resolution of 512 × 512. A ball-cube phantom was used to test the positioning accuracy of the kVCT subsystem with respect to the setup laser and MV beam. Catphan504 phantom was imaged with 0.5 pitch and 150mAs to test the kVCT image quality of the BgRT system, including the uniformity, noise, HU constancy, spatial resolution, geometric distortion, slice thickness, and low contrast visibility and detectability using the PIPSproTM software. The RTI MAS-2 and Piranha detectors were used to verify the accuracy of the mA and voltage. The CTDI dose was measured using a CTDI phantom and a Standard Imaging A101 pencil chamber.Results: The localization error of the ball cube phantom was -0.8, 0.9, and 0.3mm in IEC x, y, and z directions, respectively. For the Catphan504 tests, the vertical and horizontal uniformities were 0.926 and 0.857, respectively. The HU constancy tests of the air, water, polystyrene, acrylic, Delrin, Teflon were all within 40HU to the expected values. The modulation transfer function test results were 0.467, 0.528, and 0.595 lp/mm for F50, F40, and F30, respectively, which showed a comparable spatial resolution to regular CT simulators. The geometric distortion was 0.12mm and slice thickness inaccuracy was 0.13mm. The low contrast detectability was 0.734. The measured mA and voltage were within 5% of the nominal setting of 120 kV and 150 mA. The CTDIw was less than 1.4 cGy for body and 3 cGy for head with a protocol of 120 kVp, 150 mAs, and 1.25 mm slice thickness.Conclusion: This evaluation represents the kVCT characteristics of the novel BgRT system with architecture designed to accommodate CT, PET and a LINAC. The image quality and HU constancy are comparable to our CT simulators and is a useful tool for online adaptive radiotherapy. The commissioning data will serve as a standard for units installed at future clinical sites. [ABSTRACT FROM AUTHOR]

Summary Background To determine the relationship between the serum concentration of trefoil factor 3 (TFF3) and gastrointestinal failure (GIF) in pediatric critical illness in order to provide knowledge for disease management. Materials and methods We enrolled 137 cases and divided them into three groups, including a control group (group A), critical illness without GIF (group B), and critical illness with GIF (group C). The serum TFF3 concentration was determined by ELISA and compared among the groups. Results Serum TFF3 concentrations measured before the occurrence of GIF in group C were significantly higher than in groups A and B ( P < 0.01). Under the conditions of GIF in group C, serum TFF3 concentration was significantly related to the gastrointestinal tract function score ( r = −0.712). Cox's proportional hazards model analysis showed that the serum TFF3 concentrations at the time of occurrence of GIF, and 48 hours later, could be used as prognostic factors in critically ill pediatric patients with GIF ( r = 1.443 and 1.872, respectively). Conclusion TFF3 may play an important role in predicting GIF in pediatric critical illness and has a protective function in the mucosal repair process. [ABSTRACT FROM AUTHOR]

Kawasaki disease (KD) is the leading cause of acquired coronary disease in children and may lead to subsequent myocardial ischemia and infarction. Because coronary computed tomographic angiography (CTA) is the most sensitive noninvasive test in patients with atherosclerosis, the aim of this study was to retrospectively evaluate coronary CTA performed in patients with KD for aneurysm, stenosis, and calcified and noncalcified coronary artery disease (CAD). Clinical histories and prior stress and imaging test results were reviewed. Thirty-two patients underwent coronary CTA for KD, and 385 coronary segments were evaluated. Twenty-three of 32 patients had ≥1 diseased coronary segment. There were 20 aneurysms, 7 lesions, and 75 segments (20%) with nonobstructive CAD (16% noncalcified, 2% calcified, and 2% mixed). All nonobstructive and obstructive CAD was in patients with histories of acute-phase coronary artery dilatation or aneurysm (echocardiographic z score 4 to 44), and were almost always associated with normal stress imaging test results on followup. No lesion or CAD was found in coronary computed tomographic angiographic studies performed in a control group referred for other indications (n = 32,422 segments evaluated). The median coronary computed tomographic angiographic dose-length product was 59 mGy cm (interquartile range 32 to 131), the median unadjusted radiation dose was 0.8 mSv (interquartile range 0.4 to 1.8), and the median age- and size-adjusted radiation dose was 1.3 mSv (interquartile range 0.7 to 2.3). In conclusion, high-risk patients with histories of KD had nonobstructive and obstructive CAD not visualized by other noninvasive imaging tests. In properly selected high-risk patients with KD, coronary CTA may identify a subset at increased risk for future coronary pathology who may benefit from medical therapy. [ABSTRACT FROM AUTHOR]

Highlights: [•] Metallic sandwich beams with empty and aluminum foam filled corrugated cores. [•] Quasi-static three-point bending tests were carried on the sandwich beams. [•] Aluminum foam filling led to dramatically increased bending resistance performance. [•] Bending stiffness, initial failure load, peak load, and failure modes were predicted. [•] Failure maps were constructed to reveal the failure mechanisms. [ABSTRACT FROM AUTHOR]

There is an unmet need for timely and reliable prediction of post-cardiac arrest (CA) clinical trajectories. We hypothesized that physiological time series (PTS) data recorded on the first day of intensive care would contribute significantly to discrimination of outcomes at discharge. Adult patients in the multicenter eICU database who were mechanically ventilated after resuscitation from out-of-hospital CA were included. Outcomes of interest were survival, neurological status based on Glasgow motor subscore (mGCS) and surrogate functional status based on discharge location (DL), at hospital discharge. Three machine learning predictive models were trained, one with features from the electronic health records (EHR), the second using features derived from PTS collected in the first 24 h after ICU admission (PTS 24), and the third combining PTS 24 and EHR. Model performances were compared, and the best performing model was externally validated in the MIMIC-III dataset. Data from 2216 admissions were included in the analysis. Discrimination of prediction models combining EHR and PTS 24 features was higher than models using either EHR or PTS 24 for prediction of survival (AUROC 0.83, 0.82 and 0.79 respectively), neurological outcome (0.87, 0.86 and 0.79 respectively), and DL (0.80, 0.78 and 0.76 respectively). External validation in MIMIC-III (n = 86) produced similar model performance. Feature analysis suggested prognostic significance of previously unknown EHR and PTS 24 variables. These results indicate that physiological data recorded in the early phase after CA resuscitation contain signatures that are linked to post-CA outcome. Additionally, they attest to the effectiveness of ML for post-CA predictive modeling. [ABSTRACT FROM AUTHOR]

Abstract: Scenario discovery offers a new means to characterize and communicate the information in computer simulation models under conditions of deep uncertainty. The approach first defines scenarios as the future states of world where a proposed policy fails to meet its goals and then uses statistical algorithms to find concise descriptions of such regions in large databases of simulation model results. Current scenario discovery applications rely on the Patient Rule Induction Method (PRIM), a user-interactive bump-hunting algorithm that identifies hyper-rectangular regions in the input space of the simulation model. While often successful, scenario discovery applications have been limited because in general a policy's vulnerabilities are not well described by the PRIM's hyper-rectangular regions. This study proposes and evaluates improved scenario discovery algorithms that address this challenge with a Principal Component Analysis (PCA)-based preprocessing step that transforms the original model input parameters so that PRIM can then identify high quality hyper-rectangular scenarios in the new rotated coordination system. We explore two versions. PCA-PRIM allows rotations among all uncertain model input parameters and CPCA-PRIM (for constrained PCA-PRIM) only allows rotations among parameters within user-specified domains. The latter may provide more useful information to users, who may find scenario axes described by linear combinations of related domain parameters more interpretable than combinations of dissimilar parameters. We run two sets of tests on the PCA-PRIM and CPCA-PRIM algorithms, the first using simulated test date and the second results from a model used in a previous RAND study of the cost-effectiveness of renewable energy portfolio standards. We find that the new algorithms produce higher quality scenarios than PRIM alone as evaluated by several important measures of merit. In the test data, PCA-PRIM produces improvements averaging 37 percent, and CPCA-PRIM averaging 14 percent, over PRIM alone. In the renewable energy policy case study, PCA-PRIM and CPCA-PRIM exhibit similar improvements of about 16 percent over PRIM, and CPCA-PRIM generates scenarios interpretable by, and that provide useful information to, decision makers. [Copyright &y& Elsevier]

Purpose/objective(s): A biologically guided radiotherapy (BgRT) system was developed and equipped with a novel O-ring gantry Linac, positron emission tomography (PET) and computed tomography technologies. This architectural design is to support real-time PET-guided treatment, termed biology-guided radiotherapy. To reduce latency between PET data acquisition and radiation delivery, the BgRT system incorporates a fast-transitioning binary multi-leaf collimator (MLC) leaves sandwiched between a split-jaw. This study reports the dosimetric commissioning of the first clinical BgRT machines at our institution, and compared with the reference data provided by the manufacturer.Materials/methods: The dosimetric commissioning of the 6 MV flattening filter-free (FFF) photon beam was characterized using a 3D water phantom and diode detectors at a source to surface distance of 85 cm. In-air profiles of 40cm x 2cm field, 40cm x 1cm field, and various leaf combinations plus in water PDD data of 12 field sizes (1.25, 2.5, 5, 10, 20 and 40 cm MLC opened leaves with 1 and 2cm jaw settings) were acquired first for beam modeling. Additional longitudinal and transverse profile scans were performed for these 12 field sizes at the depth of 1.5, 5, 10, 15 and 20 cm to verify the beam model accuracy. The relative outputs factors were measured with the W2 1mmx1mm scintillator at the depth of 10cm for the field sizes from the smallest 0.6cm x 1cm to the maximum 40cm x 2cm.Results: For the PDDs of reference field size of 10cm x 2cm measured at Stanford, the maximum doses (dmax) were 12.5mm within the manufacturer's reference range of 13 ± 0.75 mm. The percentage doses at 10cm depth (d10) at reference field size were 56.9% and 57.6% for Stanford and RefleXion measurements, respectively. The longitudinal field sizes for all tested fields were agreed within 0.5mm and the transverse off-axis ratio is within 1% in the beam core (80% of nominal field size). The output factors measured at our institute were ranging from 0.706 to 1.012 relative to the reference 10cm x 2cm field.Conclusion: This evaluation represents the first commissioning evaluation of the dosimetric characteristics of the BgRT system with architecture designed to accommodate both PET detector and LINAC subsystems. This data will serve as a clinical reference for the BgRT treatment planning system's beam model and can act as a standard for comparison and beam model improvement for units installed at future clinical sites. [ABSTRACT FROM AUTHOR]

Abstract: Laser-induced breakdown spectroscopy (LIBS) has been recognized as a promising technique for analyzing sensitive nuclear materials such as uranium, plutonium, and curium in a high-radiation environment, especially since the implementation of IAEA (International Atomic Energy Agency) safeguards. The uranium spectra of ore samples were quantitatively analyzed prior to analyzing sensitive materials in the nuclear industry. The purpose of this experiment is to extract quantitative information about the uranium in a uranium ore using a standard addition approach. The uranium ore samples containing different concentrations of U were prepared by mixing raw ore powder with natural uranium oxide powders. Calibration sets of 0.2, 0.4, 0.6, 0.8 and 1.0wt.% uranium concentrations within the uranium ore sample were achieved. A pulsed and Q-switched Nd:YAG laser at a wavelength of 532nm was used as a light source. An echelle spectrometer that covers a 190–420nm wavelength range is used to generate a calibration curve and determine the detection limit of uranium in the ore matrix. The neutral atomic-emission peak at a wavelength of 356.659nm indicated a detection limit of ~158ppm for uranium, and the uranium concentration was determined in a raw ore sample that has an unknown quantity of uranium. [Copyright &y& Elsevier]

Abstract: The basic way to improve the performance of a superconducting current limiter is to apply and evaluate a superconducting device that is appropriate to the superconducting current limiter. Among the many types of superconducting devices, the YBCO thin film wire has excellent current-limiting performance that is appropriate for actual system application. For the application of the YBCO thin film wire to superconducting current limiters, its current-limiting performance as a unit device must be accurately evaluated, and measures to improve its current-limiting performance must be sought. Accordingly, to evaluate the current-limiting performance of the YBCO thin film wire, this study was conducted to evaluate its resistance-increasing trend, V max, T r, I max, I qt, and current-limiting rate as a unit device, after which the electric coupling condition that consists of a core and windings was used to evaluate the current-limiting performance of the YBCO thin film wire. [Copyright &y& Elsevier]

Abstract: The Raman spectra of N-doped 4H–SiC single crystal films is investigated between 100 and 600K. The temperature dependence of the three optical modes is obtained. These measurements reveal that all Raman peaks shift to lower frequencies with increasing temperature, except A1(LO). The temperature dependence of A1(LO) phonon modes in the round pit also manifests different features with temperature increasing, but the demarcation temperature point of the blueshift and the redshift in the round pit is higher than that in the outer area. At high temperature, all active phonon modes clearly become broader, but the linewidth of the E1(TO) phonon mode from round pit increases with temperature more rapidly than that from the outer area, this indicates that the lifetime of the E1(TO) phonon in round pit is more sensitive than that in the outer area. [Copyright &y& Elsevier]

Multidetector computed tomographic angiography defines anatomy in complex congenital heart disease, but radiation exposure and general anesthesia requirements limit its application. The aim of this study was to compare radiation exposure, anesthesia use, and diagnostic accuracy between standard-pitch, single-source computed tomography and high-pitch, dual-source computed tomography for image quality and risk in a clinical pediatric population. Consecutive computed tomographic scans were evaluated in patients aged <2 years with complex congenital heart disease. Two groups were compared on the basis of standard- versus high-pitch scans. High-pitch scans were further divided into variable pitch (2.25 to 3.0) and highest pitch (3.4) groups. Image quality, radiation exposure, anesthesia use, and diagnostic confidence and accuracy were determined. Sixty-one scans were reviewed (29 at standard pitch, 32 at high pitch). Body surface area, scan length, and indications were similar. The median dose-length product for standard-pitch scans was 66 mGy · cm (range 29 to 372) compared to 7 mGy · cm (range 3 to 50) in all high-pitch scans. The median dose-length product was 28 mGy · cm (range 8 to 50) for variable high-pitch scans and 5 mGy · cm (range 3 to 12) for the highest fixed-pitch scans. Diagnostic confidence was similar, although high-pitch scans had higher image noise and lower contrast-to-noise ratios. All high-pitch scans were performed under sedation with free breathing, and all standard-pitch scans required general anesthesia. Diagnostic accuracy was 100% in the 2 groups, with 17 standard-pitch and 16 high-pitch patients undergoing procedural validation. In conclusion, high-pitch, dual-source computed tomography provides excellent diagnostic accuracy and markedly reduces radiation dose, although image quality is mildly reduced. [Copyright &y& Elsevier]

Abstract: The APOE4 allele is the most common genetic determinant for Alzheimer''s disease (AD) in the developed world. APOE genotype specific differences in brain apolipoprotein E protein levels have been observed in numerous studies since the discovery of APOE4''s link to AD. Since the human apoE4 targeted replacement mice display characteristics of cognitive impairment we sought to determine if reduced levels of apoE might provide one explanation for this impairment. We developed a novel mass spectrometry method to measure apoE protein levels in plasma. Additionally, we developed an ELISA that replicates the mass spectrometry data and enables the rapid quantitation of apoE in plasma, brain and cerebrospinal fluid. We detected a significant decrease in plasma, brain and cerebrospinal fluid apoE levels in the apoE4 mice compared to apoE2 and E3 mice. We also measured a small (∼19%) decrease in brain apoE levels from aged, non-demented APOE4 carriers. Our findings suggest that a fraction of APOE4-linked AD may be due to insufficient levels of functional apoE required to maintain neuronal health. [Copyright &y& Elsevier]

Leishmania parasites are pteridine auxotrophs that use an NADPH-dependent pteridine reductase 1 (PTR1) and NADH- dependent quinonoid dihydropteridine reductase (QDPR) to salvage and maintain intracellular pools of tetrahydrobiopterin (H4B). However, the African trypanosome lacks a credible candidate QDPR in its genome despite maintaining apparent QDPR activity. Here we provide evidence that the NADH-dependent activity previously reported by others is an assay artifact. Using an HPLC-based enzyme assay, we demonstrate that there is an NADPH-dependent QDPR activity associated with both TbPTR1 and LmPTR1. The kinetic properties of recombinant PTR1s are reported at physiological pH and ionic strength and compared with LmQDPR. Specificity constants (kcat/Km) for LmPTR1 are similar with dihydrobiopterin (H2B) and quinon-old dihydrobiopterin (qH2B) as substrates and about 20-fold lower than LmQDPR with qH2B. In contrast, TbPTR1 shows a 10-fold higher kcat/Km for H2B over qH2B. Analysis of Trypanosoma brucei isolated from infected rats revealed that H4B (430 nM, 98% of total biopterin) was the predominant intracellular pterin, consistent with a dual role in the salvage and regeneration of H4B. Gene knock-out experiments confirmed this: PTR1-nulls could only be obtained from lines overexpressing LrnQDPR with H4B as a medium supplement. These cells grew normally with H4B, which spontaneously oxidizes to qH2B, but were unable to survive in the absence of pterin or with either biopterin or H2B in the medium. These findings establish that PTR1 has an essential and dual role in pterin metabolism in African trypanosomes and underline its potential as a drug target. [ABSTRACT FROM AUTHOR]

Abstract: Water cavitation peening is a technique similar to shot peening that induces compressive residual stresses in materials for improved fatigue resistance. Generally, residual stress is of two types: macro-residual stress and micro-residual stress. In this paper, a novel combined finite element method and dislocation density method (FEM/DDM), proposed for predicting macro and micro-residual stresses induced on the material subsurface treated with water cavitation peening, is presented. A bilinear elastic–plastic finite element method was conducted to predict macro-residual stresses and a dislocation density method was conducted to predict micro-residual stresses. These approaches made possible the prediction of the magnitude and depth of residual stress fields in pure titanium. The effect of applied impact pressures on the residual stresses was also presented. The results of the FEM/DDM modeling were in good agreement with those of the experimental measurements. [Copyright &y& Elsevier]

Abstract: Background: The regeneration of splenic autotransplants remains unsatisfactory. The liver has a rich blood supply and is prone to form collateral vessels to nearby ischemic tissues. It should be valuable to study whether it is a new site to facilitate splenic regeneration. Materials and Methods: One hundred twenty Sprague-Dawley rats were randomly divided into 12 groups. After splenectomy, each weighed spleen was attached to the diaphragmatic side of the left hepatic lobe using an adhesive. The rats were sacrificed on postoperative day(POD)s 1, 3, 7, 14, 21, 28, 35, 42, 49, 56, 70, and 84. Six spleens in each group were dissected for weighing and another 4 for histologic analysis (H&E). Splenic autografts of another 12 rats attached to the mesenterium were sacrificed on POD 28, 56, and 84 for histologic analysis (H&E). Results: The spleens attached to the liver underwent almost complete necrosis and then regenerated centripetally into structures comparable to a normal spleen, with typical red and white pulps as well as a marginal zone on POD 35. The mass of the implants recovered to more than two fifths of the original (44.2% ± 3.6%) on POD 84. For splenic autografts attached to mesenterium, typical red and white pulps were observed on POD 56. The marginal zone was not clear on POD 84. Conclusion: The liver proved to be an appropriate site for splenic autotransplantation. Regeneration was histologically superior to that of splenic tissue attached to the mesenterium. The application of a tissue adhesive may be a new technique for splenic autotransplantation. [Copyright &y& Elsevier]

PURPOSE: To estimate and compare prevalence rates of lifetime health conditions by inferred duration of illicit drug use among the general U.S. adult population and to investigate associations between duration of use of each specific illicit drug (marijuana, cocaine, heroin, hallucinogens, or inhalant) and each lifetime health condition after controlling for potential confounding factors. METHODS: Data from respondents aged 35 to 49 (N = 29,195) from the 2005-2007 National Surveys on Drug Use and Health (NSDUH) were analyzed. RESULTS: The prevalence rates of a broad range of health conditions by duration of use of specific illicit drug among persons 35 to 49 years of age in the United States were estimated and compared. After adjustment for potential confounding factors, the results of 20 multivariate logistic regression models indicated positive associations between duration of marijuana use and anxiety, depression, sexually transmitted disease (STD), bronchitis, and lung cancer; between duration of cocaine use and anxiety and pancreatitis; between duration of heroin use and anxiety, hepatitis, and tuberculosis; between duration of hallucinogen use and tinnitus and STD; and between duration of inhalant use and anxiety, depression, HIV/AIDS, STD, tuberculosis, bronchitis, asthma, sinusitis, and tinnitus. CONCLUSIONS: This study provides initial analyses on the relationships between illicit drug use and health conditions based on a large nationally representative sample. These results can help prepare for treating health problems among former and continuing illicit drug users. [ABSTRACT FROM AUTHOR]

Abstract: Water cavitation peening is a recent promising method in surface treatment. It has the potential to induce compressive residual stresses that benefit the fatigue life of components similar to the other peening process. In this paper, a novel method, proposed for predicting residual stress induced on the materials subsurface treated with water cavitation peening, is presented. A bilinear elastic–plastic finite element analysis was conducted to predict to residual stresses. The three-dimensional model was based on the classical bilinear kinematic hardening model that uses two slopes (elastic and plastic) to represent the stress–strain behavior of a material. The approach provided prediction of magnitude and depth of residual stress fields in pure titanium. Effect of applied impact pressures on the residual stresses was also presented. Results of the finite element analysis modeling were in good agreement with that of the experimental measurements. [Copyright &y& Elsevier]

Abstract: The influence of water cavitation peening (WCP) treatment on the microstructure of pure titanium was investigated. The microstructural evolution in the near-surface of pure titanium as a function of WCP time was characterized by X-ray diffraction (XRD), optical microscopy (OM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). After WCP treatment, changes in the microstructure, as well as residual stress and surface morphologies as functions of WCP time, were recorded using a novel experimental design involving an in situ observation function. The obtained results indicate that twinning plays an important role in the plastic deformation and residual stresses of hexagonal close-packed (HCP) structured metal materials, and therein, that the deformation twinning and twinning interaction were induced by WCP in the strengthening layer. A stable compressive residual stress layer was found in the near-surface of the investigated pure titanium. [Copyright &y& Elsevier]

Abstract: Estrogens play an important role in the development and progression of breast cancer. 17β-Hydroxysteroid dehydrogenase (17β-HSD) type 2 and type 5 are involved in sex steroid metabolism. 17β-HSD type 2 converts estradiol to estrone while 17β-HSD type 5 converts androstenedione to testosterone. Using immunocytochemistry, we have studied the expression of 17β-HSD type 2 and type 5 in 50 specimens of breast carcinoma and adjacent non-malignant tissues. The results were correlated with the estrogen receptor α (ERα) and β (ERβ), progesterone receptor A (PRA) and B (PRB), androgen receptor and CDC47 and with the tumor stage, tumor size, nodal status and menopausal status. 17β-HSD type 2 was expressed in 20% and 17β-HSD type 5 in 56% of breast cancer specimens. In adjacent normal tissues, both enzymes were highly expressed in almost all the patients. No significant association could be found between the expression of 17β-HSD type 2 and 17β-HSD type 5 and between the expression of each enzyme and the clinicopathological parameters studied. The decrease in 17β-HSD type 2 and 17β-HSD type 5 expressions in breast cancer may play a predominant role in the development and/or progression of the cancer by modifying the intratumoral levels of estrogens and androgens. [Copyright &y& Elsevier]

Abstract: In this paper, we investigate the convergence behavior of a Runge–Kutta type modified Landweber method for nonlinear ill-posed operator equations. In order to improve the stability and convergence of the Landweber iteration, a 2-stage Gauss-type Runge–Kutta method is applied to the continuous analogy of the modified Landweber method, to give a new modified Landweber method, called R–K type modified Landweber method. Under some appropriate conditions, we prove the convergence of the proposed method. We conclude with a numerical example confirming the theoretical results, including comparisons to the modified Landweber iteration. [Copyright &y& Elsevier]

Abstract: Water cavitation peening (WCP) with aeration is a recent potential method in the surface enhancement techniques. In this method, a ventilation nozzle is adopted to improve the process capability of WCP by increasing the impact pressure, which is induced by the bubble collapse on the surface of components in the similar way as conventional shot peening. In this paper, fatigue tests were conducted on the both-edge-notched flat tensile specimens to assess the influences of WCP on fatigue behaviour of SAE1045 steel. The notched specimens were treated by WCP, and the compressive residual stress distributions in the superficial layer were measured by X-ray diffraction method. The tension–tension (R = S min/S max =0.1, f =10Hz) fatigue tests and the fracture surfaces observation by scan electron microscopy (SEM) were conducted. The experimental results show that WCP can improve the fatigue life by inducing the residual compressive stress in the superficial layer of mechanical components. [Copyright &y& Elsevier]

Abstract: In this paper we propose the R-K type Landweber iteration and investigate the convergence of the method for nonlinear ill-posed problem where is a nonlinear operator between Hilbert space H. Moreover, for perturbed data with noise level we prove that the convergence rate is under appropriate conditions. Finally, the numerical performance of this R-K type Landweber iteration for a nonlinear convolution equation is compared with the Landweber iteration. [Copyright &y& Elsevier]

Abstract: By introducing the wavelet multiscale method and the homotopy method to the inversion process for the velocity estimation problem of two-dimensional acoustic wave equation in seismic prospecting, a joint inversion method—wavelet multiscale–homotopy method is designed, which is stable, globally convergent, and has the ability of noise suppression. The results of numerical simulations and noise suppression tests indicate our method’s effectiveness. [Copyright &y& Elsevier]

Abstract: We develop a homotopy method for nonlinear inverse problems, where the forward problems are governed by some forms of differential equations. A Tikhonov-style regularization approach yields an optimization problem. Ordinary iterative methods may fail to solve this problem, due to their locally convergent properties. Then the fixed-point homotopy method is introduced to solving the normal equation of the optimization problem, and a new and globally convergent algorithm is constructed, which is highly effective in the aspects of speed of computation, ability of noise suppression and wide region of convergence. As a practical application, the method is used to solve the inverse problem of 2-D acoustic wave equation. We demonstrate the merits and effectiveness of our algorithm on two realistic model problems. [Copyright &y& Elsevier]

Abstract: Global systolic and diastolic LV function assessed by conventional echocardiographic indices is often normal in patients with controlled hypertension, with or without left ventricular hypertrophy. However, it is not certain whether regional myocardial function in these patients remains normal. We investigated 26 patients and 10 age matched normal controls, by means of long axis M-mode echocardiography. There was no significant difference in age, sex distribution, heart rate, blood pressure and routine ECG measurements between the two groups. Although there was significant LVH in patients compared to normal controls, LV cavity size and global systolic function, assessed by shortening fraction, ejection fraction and mean velocity of circumferential fibre shortening did not differ between the two groups, nor did LV diastolic function, assessed by the mitral flow pattern. However, LV regional mechanics, as assessed by multiple long axis M-mode echocardiograms differed significantly, in both systole and diastole, between the two groups. Compared to controls, the total longitudinal systolic excursion in both LV free wall and ventricular septum were significantly reduced in patients, and so was maximum early relaxation and atrial contraction in the LV free wall. The mean rate of systolic excursion in all 3 sites did not differ between the two groups, but the mean rate of early relaxation in both LV free wall and ventricular septum was significantly decreased in patients compared to normal controls. In conclusion, the evaluation of LV dysfunction in patients who have achieved good blood pressure control requires more than a conventional echocardiographic assessment. The assessment of regional mechanics described in the present paper offers an easy and sensitive method for the detection of subtle signs of LV mechanical inefficiency associated with LVH. [Copyright &y& Elsevier]

Abstract: In order to investigate whether horizontal plane QRS axis predicts the prognosis in elderly heart failure, we studied 80 consecutive patients by clinical assessment, ECG, Doppler and echocardiography. All patients were followed up for 2 years, 12 died and 68 survived. Age, gender distribution, blood pressure, co-existing diagnoses and medication were all similar between those who died and those who survived. The NYHA classification was significantly worse, left ventricular (LV) cavity size was greater, LV systolic function was lower in those who died than in survivors, despite similar LV wall thickness. On ECG, heart rate, PR interval, QT interval and frontal QRS axis did not differ between the two groups. The QRS duration was significantly longer and the horizontal QRS axis projected to a substantially more posterior direction in those who died than in survivors. The sensitivity and specificity of a horizontal QRS axis ≤−30° for predicting death in 2 years were 75% and 62%, respectively. The former is above the sensitivity of a NYHA ≥3 and the latter is above the specificity of a LV shortening fraction ≤20%. The combination of a QRS horizontal axis ≤−30° and NYHA ≥3 predicted 2 year mortality with a sensitivity of 75% and specificity of 91%. In conclusion, a left posterior QRS axis of the horizontal plane in elderly heart failure indicates an adverse prognosis, particularly when combined with NYHA classification and echocardiographic assessment. [Copyright &y& Elsevier]

Abstract: An algorithm of the generalized pulse-spectrum technique (GPST) is used for the inverse problems of two-dimensional acoustic wave equation, and a skill of saving computational cost is designed in choosing regularizing parameters. To overcome the defect of the local convergence of the GPST, a widely convergent GPST (WCGPST) is constructed. Numerical simulations are carried out to test the feasibility and to study the general characteristics of the WCGPST. It is found that the WCGPST is not only as robust as the standard GPST but also possessing widely convergent region. [Copyright &y& Elsevier]

Abstract: Biotechnological manufacturing processes often include a bioreactor harvesting step which involves separation of cells, cell debris and other particulate matter from the suspending medium which frequently contains the product of interest. Tangential flow microfiltration is used to separate the particulate matter from the suspending medium. The efficiency of this microfiltration step is often improved by increasing the particle size through flocculation prior to microfiltration. Here flocculation of yeast suspensions using a cationic polyelectrolyte has been investigated. A self-similar steady state floc size distribution is obtained experimentally. The experimental results may be modeled using a population balance approach. The dimensionless floc size distribution is found to be independent of the particulate volume fraction, initial particle size and shear rate during flocculation for the ranges of these variables considered. However, the actual floc size distribution does depend upon these parameters. In addition, the approach to the self-similar steady state floc size distribution depends upon the particulate volume fraction. At higher particulate volume fractions, the volume average floc size is found to increase during flocculation, pass through a maximum and then decrease to the final steady state value. However, at lower particle volume fractions, a maximum in the volume average floc size is not observed. Flocculation of cells leads to an increase in the volume average particle diameter. However, it also leads to a broadening of the particle size distribution. Consequently, when determining the improvement in permeate flux for tangential flow microfiltration, it is essential to include the effects of an increased average particle diameter and a broadened particle size distribution. [Copyright &y& Elsevier]

Abstract: Bond distance, vibrational frequency and dissociation energy of Re2, Os2 and Ir2 were studied by density functional methods B3LYP, BLYP, B3PW91, BHLYP, BP86, B3P86 and PBE1PBE. Spin multiplicity 7 is the ground state for Os2, 5 for Ir2. For Re2, the ground state spin multiplicity is sensitive to the density functionals. Spin multiplicity 5 is the ground state for B3LYP, B3PW91, B3P86, and PBE1PBE, while triplet state is the ground state for BLYP, BP86, and BHLYP. The calculated bond distances are less sensitive to the methods used, while it is not true for vibrational frequencies and dissociation energies. [Copyright &y& Elsevier]

Abstract: Aim: The aim of this study was to investigate the safe time limits of cold preservation in University of Wisconsin (UW) solution of liver grafts subjected to warm ischemia (WI) for 30 minutes from non–heart-beating donors (NHBDs). Methods: The safe time limits were studied in a simple porcine orthotopic liver transplantation (LTx) model. In donors, livers were subjected to 30 minutes of WI and subsequent 6-hour (Group 1, n = 5), 10-hour (Group 2, n = 5), and 14-hour (Group 3, n = 3) cold preservation in UW solution. Results: All 5 animals in Group 1 survived up to 7 days, the survey endpoint. In Group 2, only 2 animals survived to the same survey endpoint. All animals in Group 3 died within 12 hours. The 1-week survival rate of Group 1 was significantly higher than those of the other 2 groups. Group 1 showed a lower level of alanine aminotransferase (ALT) or aspartate aminotransferase (AST) after LTx, less pathological damage, higher concentration of adenosine triphosphate (ATP), and higher microcirculation blood flux in the grafted liver tissue at 1 hour after reperfusion than the other 2 groups. Conclusions: It is concluded that about 6 hours is the safe time limit of cold preservation in UW solution for liver grafts from NHBDs subjected to WI for 30 minutes. [Copyright &y& Elsevier]

Equilibrium geometries, vibrational frequencies and dissociation energies of hafnium dimer and trimer were studied by density functional methods B3LYP, BLYP, B3PW91, BHLYP, BP86, B3P86, mPW1PW91 and PBE1PBE. The results indicate that singlet is the ground state both for hafnium dimer and for trimer. For hafnium dimer, the calculated bond distance is less sensitive to the methods used. Except at BHLYP level, the calculated vibrational frequency is comparable to the experimental value. For hafnium trimer, equilateral triangle with D3h symmetry is slightly favored compared with isosceles triangle with C2v symmetry except at BHLYP level. This conclusion is in agreement with experiment in which the ground state of Hf3 is fluxional and low-spin or closed shell is preferred. [Copyright &y& Elsevier]

Deep-level defects formed in InGaN:Mg have been investigated by photoluminescence (PL) spectroscopy. Undoped In0.07Ga0.93N exhibits strong bandedge emission at 3.05 eV. Upon Mg doping the bandedge emission quenches and a 2.45 eV green band with a full-width at half-maximum of 800 meV dominates the room temperature PL spectrum. This band is attributed to donor–acceptor pair (DAP) recombination involving Mg acceptors and nitrogen vacancy donors. A decrease in the DAP emission bandwidth and an S-shaped emission shift with increasing temperature were observed and attributed to compositional fluctuations. In order to decrease the fluctuations, InGaN:Mg epilayers with a GaN capping layer were annealed at high temperature. As a result of the fluctuation reduction a fine structure related to phonon replicas was resolved. The measured phonon energy and the Huang–Rhys factor were 105 meV and 6.3, respectively, indicating strong electron–phonon coupling is responsible for the large width of the green band. [Copyright &y& Elsevier]

The mechanism of energy separation in a free jet and its enhancement by acoustic excitation are investigated using an experimental technique to measure instantaneous velocity and total temperature simultaneously. The measured velocity and total temperature data are analyzed and compared by both time-averaged and spectral methods. By introducing the skewness of the total temperature fluctuation, the characteristics of energy separation can be identified. The results show that the frequencies of dominant total temperature fluctuation coincide with those of velocity fluctuation which represent the passing frequencies of vortices at give locations. This confirms that the mechanism of energy separation is induced by the motion of the coherent vortical structure which generates pressure fluctuation with the flow field. Spectral analysis of the data with acoustic excitation indicate that the enhancement of energy separation by acoustic excitation should result from vortex pairing processes induced by the acoustic excitation. [Copyright &y& Elsevier]

“Energy separation” is the re-distribution of the total energy in a fluid flow without external work or heat, and has potential to heat or cool a fluid without using a conventional heating or cooling system. However, currently obtainable heating and/or cooling effects are not big enough for practical applications. It is required to understand the mechanism of energy separation and investigate its enhancement methods. In the present study which consists of two parts, energy separation in a free jet is investigated with instantaneous velocity and total temperature measurements. As a method to enhance energy separation, acoustic excitation with various frequencies is examined. In this first part, an experimental study is performed to investigate the motion of the coherent vortical structure and its response to acoustic excitation in free jets whose Reynolds numbers are 8000 and 120,000. For the low Reynolds number jet, spectral analysis of instantaneous velocity and flow visualization by a schlieren system are performed to characterize the motion of the large scale coherent vortical structure. The frequency of dominant fluctuation, which represents the vortex passing frequency at a given axial location, is around SrD&ap;0.65 at z/D=1 and moves to SrD&ap;0.4 at z/D=4. When acoustic excitation is applied, the coherent structure develops more rapidly than in the absence of excitation regardless of the excitation frequency, but very regular and strong vortex pairing is observed only when acoustic excitation with Srex=0.9. The flow characteristics of the high Reynolds number jet are also investigated with spectral analysis. The result shows that the velocity fluctuation level is generally elevated, but the frequency of dominant fluctuation is still within 0.4&les;SrD&les;0.6. The response to acoustic excitation is also very similar to the low Reynolds number jet. [Copyright &y& Elsevier]

Non-agglomerated spherical silicon, titanium and zirconium oxide nanoparticles were prepared using an electrospray assisted chemical vapor deposition (ES-CVD) process. Metal alkoxides in conjunction with an electrospray method were used to introduce charged precursors into a CVD reactor. The ions are produced during evaporation of the charged droplets, and they probably act as seed nuclei (i.e., ion-induced nucleation) and/or, they are attached to the produced particles. The experimental results were compared with those obtained using a conventional evaporation CVD method. The particles generated using the conventional evaporation method were agglomerated to a considerable extent irregardless of the type of particle. Whereas, at the same conditions, high concentrations of non-agglomerated nanoparticles having diameters in the range of 10–40 nm were obtained using the ES-CVD method. This appears to be due to the charging effects of the generated particles, that is, the electrostatic dispersion of unipolarly charged particles. The size of the non-agglomerated particles in the ES-CVD method was reduced as the results of the decease in the concentration of precursors introduced by electrospray. [Copyright &y& Elsevier]