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Carrier distribution and dynamics in semiconductor materials often govern their physical properties that are critical to functionalities and performance in industrial applications. The continued miniaturization of electronic and photonic devices calls for tools to probe carrier behavior in semiconductors simultaneously at the picosecond time and nanometer length scales. Here, we report pump–probe optical nanoscopy in the visible-near-infrared spectral region to characterize the carrier dynamics in silicon nanostructures. By coupling experiments with the point-dipole model, we resolve the size-dependent photoexcited carrier lifetime in individual silicon nanowires. We further demonstrate local carrier decay time mapping in silicon nanostructures with a sub-50 nm spatial resolution. Our study enables the nanoimaging of ultrafast carrier kinetics, which will find promising applications in the future design of a broad range of electronic, photonic, and optoelectronic devices.

Tumor lysis syndrome (TLS) is a life‐threatening oncologic emergency associated with fatal complications including arrhythmia. The epidemiology and mortality outcomes of arrhythmia in TLS are scarcely studied in the literature. We used the National Inpatient Sample (NIS) to study the prevalence and outcome of arrhythmia in patients hospitalized with TLS (ICD‐9 code 277.88) from 2009 to 2014. Baseline characteristics, burden of arrhythmia, and pertinent outcomes were analyzed. Multivariable regression analysis was performed to identify the impact of underlying malignancy in predicting TLS‐related mortality. A total of 9034 cases of arrhythmia among 37 861 TLS patients were identified. More than half of the arrhythmia cases (67%) were found among white old (>65) males admitted to large bed size and urban teaching hospitals. Arrhythmic cohort showed higher frequency of comorbidities such as fluid‐electrolyte disturbances, hypertension, congestive heart failure, renal failure, dyslipidemia, diabetes, pulmonary circulatory disorders, chronic pulmonary disease, coagulopathy, and deficiency anemia. The most common malignancies were leukemia, lymphoma, metastatic tumor, and solid tumor without metastasis. We found significantly higher odds of in‐hospital mortality among patients with TLS compared to general inpatient population on unadjusted (OR 9.69, 95% CI: 9.27‐10.13, P< .001) and adjusted (OR 4.62, 95% CI: 4.39‐4.85) multivariable analyses. Overall in‐hospital mortality (32% vs 21.3%), median length of stay (11 days vs 9 days), and hospital charges were higher among arrhythmic than nonarrhythmic patients. With the availability of more advanced cancer therapy in the US, nearly one in four inpatient encounters of TLS had arrhythmia. Arrhythmia in TLS patients was associated with higher odds of mortality and increased resource utilization. Therefore, strategies to improve the supportive care of TLS patients plus timely diagnosis and treatment of arrhythmia are of utmost importance in reducing mortality and health‐care cost. A total of 23.9% of (n = 9034) encounters with arrhythmia were identified, out of 37 861 TLS‐related hospitalizations. The trends in the prevalence of arrhythmia were stable with rates ranging from 19.8% to 25.8%, with the highest frequency recorded in 2014 (25.8%) (Figure 1A). Atrial fibrillation (13.6%) was the most common arrhythmia followed by ventricular tachycardia in 2.6% of patients (Figure 1B).

An electro-thermal annealing (ETA) method, which uses an electrical pulse of less than 100 ns, was developed to improve the electrical performance of array-level amorphous-oxide-semiconductor (AOS) thin-film transistors (TFTs). The practicality of the ETA method was experimentally demonstrated with transparent amorphous In–Ga–Zn-O (a-IGZO) TFTs. The overall electrical performance metrics were boosted by the proposed method: up to 205% for the trans-conductance (gm), 158% for the linear current (Ilinear), and 206% for the subthreshold swing (SS). The performance enhancement were interpreted by X-ray photoelectron microscopy (XPS), showing a reduction of oxygen vacancies in a-IGZO after the ETA. Furthermore, by virtue of the extremely short operation time (80 ns) of ETA, which neither provokes a delay of the mandatory TFTs operation such as addressing operation for the display refresh nor demands extra physical treatment, the semipermanent use of displays can be realized.

This work is concerned with the kinetics of laser-induced reductive sintering of nonstoichiometric crystalline nickel oxide (NiO) nanoparticles (NPs) under ambient conditions. The mechanism of photophysical reductive sintering upon irradiation using a 514.5 nm continuous-wave (CW) laser on NiO NP thin films has been studied through modulating the laser power density and illumination time. Protons produced due to high-temperature decomposition of the solvent present in the NiO NP ink, oxygen vacancies in the NiO NPs, and electronic excitation in the NiO NPs by laser irradiation all affect the early stage of the reductive sintering process. Once NiO NPs are reduced by laser irradiation to Ni, they begin to coalesce, forming a conducting material. In situoptical and electrical measurements during the reductive sintering process take advantage of the distinct differences between the oxide and the metallic phases to monitor the transient evolution of the process. We observe four regimes: oxidation, reduction, sintering, and reoxidation. A characteristic time scale is assigned to each regime.

We introduce a method for direct patterning of Ni electrodes through selective laser direct writing (LDW) of NiO nanoparticle (NP) ink. High-resolution Ni patterns are generated from NiO NP thin films by a vacuum-free, lithography-free, and solution-processable route. In particular, a continuous wave laser is used for the LDW reductive sintering of the metal oxide under ambient conditions with the aid of reducing agents in the ink solvent. Thin (∼40 nm) Ni electrodes of glossy metallic surfaces with smooth morphology and excellent edge definition can be fabricated. By applying this method, we demonstrate a high transmittance (>87%), electrically conducting panel for a touch screen panel application. The resistivity of the Ni electrode is less than an order of magnitude higher compared to that of the bulk Ni. Mechanical bending test, tape-pull test, and ultrasonic bath test confirm the robust adhesion of the electrodes on glass and polymer substrates.

Introduction Several prediction scores for triaging patients with upper gastrointestinal (GI) bleeding have been developed, yet these scores have never been compared to the current gold standard, which is the clinical evaluation by a gastroenterologist. The aim of this study was to assess the added value of prediction scores to gastroenterologists’ Gut Feeling in patients with a suspected upper GI bleeding.Methods We prospectively evaluated Gut Feeling of senior gastroenterologists and asked them to estimate: (1) the risk that a clinical intervention is needed; (2) the risk of rebleeding; and (3) the risk of mortality in patients presenting with suspected upper GI bleeding, subdivided into low, medium, or high risk. The predictive value of the gastroenterologists’ Gut Feeling was compared to the Blatchford and Rockall scores for various outcomes.Results We included 974 patients, of which 667 patients (68.8%) underwent a clinical intervention. During the 30-day follow up, 140 patients (14.4%) developed recurrent bleeding and 44 patients (4.5%) died. Gut Feeling was independently associated with all studied outcomes, except for the predicted mortality after endoscopy. Predictive power, based on the AUC of the Blatchford and Rockall prediction scores, was higher than the Gut Feeling of the gastroenterologists. However, combining both the Blatchford and Rockall scores and the Gut Feeling yielded the highest predictive power for the need of an intervention (AUC 0.88), rebleeding (AUC 0.73), and mortality (AUC 0.71 predicted before and 0.77 predicted after endoscopy, respectively).Conclusions Gut Feeling is an independent predictor for the need of a clinical intervention, rebleeding, and mortality in patients presenting with upper GI bleeding; however, the Blatchford and Rockall scores are stronger predictors for these outcomes. Combining Gut Feeling with the Blatchford and Rockall scores resulted in the most optimal prediction.

Several prediction scores for triaging patients with upper gastrointestinal (GI) bleeding have been developed, yet these scores have never been compared to the current gold standard, which is the clinical evaluation by a gastroenterologist. The aim of this study was to assess the added value of prediction scores to gastroenterologists’ Gut Feeling in patients with a suspected upper GI bleeding. We prospectively evaluated Gut Feeling of senior gastroenterologists and asked them to estimate: (1) the risk that a clinical intervention is needed; (2) the risk of rebleeding; and (3) the risk of mortality in patients presenting with suspected upper GI bleeding, subdivided into low, medium, or high risk. The predictive value of the gastroenterologists’ Gut Feeling was compared to the Blatchford and Rockall scores for various outcomes. We included 974 patients, of which 667 patients (68.8%) underwent a clinical intervention. During the 30-day follow up, 140 patients (14.4%) developed recurrent bleeding and 44 patients (4.5%) died. Gut Feeling was independently associated with all studied outcomes, except for the predicted mortality after endoscopy. Predictive power, based on the AUC of the Blatchford and Rockall prediction scores, was higher than the Gut Feeling of the gastroenterologists. However, combining both the Blatchford and Rockall scores and the Gut Feeling yielded the highest predictive power for the need of an intervention (AUC 0.88), rebleeding (AUC 0.73), and mortality (AUC 0.71 predicted before and 0.77 predicted after endoscopy, respectively). Gut Feeling is an independent predictor for the need of a clinical intervention, rebleeding, and mortality in patients presenting with upper GI bleeding; however, the Blatchford and Rockall scores are stronger predictors for these outcomes. Combining Gut Feeling with the Blatchford and Rockall scores resulted in the most optimal prediction.

To demonstrate a first step for a novel fabrication method of a flexible display, nanomaterial based laser processing schemes to demonstrate organic light emitting diode (OLED) pixel transfer and organic field effect transistor (OFET) fabrication on a polymer substrate without using any conventional vacuum or photolithography processes were developed. The unique properties of nanomaterials allow laser induced forward transfer of organic light emitting material at low laser energy while maintaining good fluorescence and also allow high resolution transistor electrode patterning at plastic compatible low temperature. These novel processes enable an environmentally friendly and cost effective process as well as a low temperature manufacturing sequence to realize inexpensive, large area, flexible electronics on polymer substrates.

A fully transparent non‐volatile memory thin‐film transistor (T‐MTFT) is demonstrated. The gate stack is composed of organic ferroelectric poly(vinylidene fluoride‐trifluoroethylene) [P(VDF‐TrFE)] and oxide semiconducting Al‐Zn‐Sn‐O (AZTO) layers, in which thin Al2O3is introduced between two layers. All the fabrication processes are performed below 200 °C on the glass substrate. The transmittance of the fabricated device was more than 90% at the wavelength of 550 nm. The memory window obtained in the T‐MTFT was 7.5 V with a gate voltage sweep of −10 to 10 V, and it was still 1.8 V even with a lower voltage sweep of −6 to 6 V. The field‐effect mobility, subthreshold swing, on/off ratio, and gate leakage currents were obtained to be 32.2 cm2V−1s−1, 0.45 V decade−1, 108, and 10−13A, respectively. All these characteristics correspond to the best performances among all types of non‐volatile memory transistors reported so far, although the programming speed and retention time should be more improved.

We presented effect of substrate buffer layer on the staggered ZnO TFT performance. Thermal oxide with smooth surface and negligible hydrogen amount forms good back channel with the ZnO active layer deposited by PEALD to result in high performance of ZnO TFT. On the other hand, PECVD SiO2 buffer layer generates some defects in the back channel and make PEALD ZnO have higher carrier density to result in much negatively shifted Von and reduced mobility of TFT. ZnO TFT having sputtered SiO2 as a buffer layer showed similar performance to that with thermal oxide.

A series of surface-modified TiO2 nanoparticles were prepared and their photocatalytic effects were evaluated by degradation of Acid red dye in aqueous solution under UV light irradiation. Phage display peptide libraries were used for peptide sequence to bind the doped TiO2 particles selectively.

Zinc oxide thin films were grown in a temperature range of 70 to 180oC by means of plasma enhanced atomic layer deposition (PEALD) for the first time. The films have growth rate of 1.9Aa/cycle. The XRD patterns showed more or less random orientation of ZnO films grown by PEALD, but the reduced plasma power resulted in preferred (002) orientation of films at 150oC. The sheet resistivity of films grown with oxygen plasma was too high to measure with 4 point probe and Hall measurement system. The difference of electrical property between PEALD and H2O-based ALD films is attributed to a different O/Zn atomic ratio.

Abstract Syntheses and characterizations of sol–gel precursors of Sr2CeO4 were carried out. Each molecular precursor, [Sr2Ce(OCH2CH2OCH3)8] (1), [Sr2Ce(OiPr)8] (2) and [Sr2Ce2(OiPr)12(iPrOH)4] (3) was prepared from mixtures of Sr complexes and cerium(IV) alkoxides. The molecular structure of 3 showed that [CeO6] octahedra are connected with distorted [SrO6] octahedra by sharing edges with oxo bridges. X-ray powder diffraction patterns and spectrofluorometry were used to determine the evolution of structure from the precursor molecules to the luminescent oxides. The luminescent strontium cerium oxides were derived at relatively mild reaction conditions (700 °C for 1 h), and complete conversion was observed at 1000 °C for 1 h from these precursors. Comparing the spectra of the oxides derived from 2 and 3, the emission intensity of the oxide derived from 2 is much stronger.

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Microwave spectra of the three Group 13 metal cyanide pairs AlNC/AlCN, GaNC/GaCN, and InNC/InCN have been measured in the frequency range 6–25 GHz using a pulsed jet cavity Fourier transform microwave spectrometer. The molecules were prepared by ablating the metal with a pulsed Nd:YAG laser and allowing the vapor to react with cyanogen or acetonitrile contained in the Ar backing gas of the jet. The spectra are those of linear molecules. Rotational constants, centrifugal distortion constants, and nuclear quadrupole coupling constants have been precisely evaluated. Molecular geometries determined from the rotational constants using a linear model have revealed unexpectedly short NC bond lengths for the isocyanides, MNC, and are interpreted in terms of a broadened potential well for the bending mode of these molecules. This interpretation is confirmed with ab initiocalculations. The centrifugal distortion constants are consistent with this picture. A new formulation of the rigid bender model has produced plausible values for bond lengths and bending amplitudes for the isocyanides. The 14N quadrupole coupling constants are discussed in terms of the approximate bending amplitudes. A description of the bonding in the molecules has been obtained using Townes–Dailey theory.

Abstract A characterization of sol-gel precursors of SrBi2Ta2O9 (SBT) has been carried out. Each molecular precursor, [SrBi2+xTa2(OCH2CH2OCH3)18]n (1) (x = 0.0, 0.2, and 0.4) and [SrTa2(OEt)(OiPr)11(iPrOH)2] (2) was prepared from the mixtures of Bi(OR)3, Sr(OR)2, and Ta(OR)5 (R = Et, iPr, and CH2CH2OCH3), respectively. 1H and 13C NMR spectroscopy and powder X-ray diffractometry have been used to characterize precursor molecules and their oxides, respectively. Especially, X-ray single crystal studies of complex 2 show that the molecule is made up of three octahedra; the central [SrO6] octahedron is sharing two neighboring edges with the peripheral [TaO6] ones. The SBT film derived from the precursor 1 presents outstanding ferroelectric properties (Pr = 9 µC/cm2; Ec = 0.8 V).

Growth hormone (GH) exerts sexually dimorphic effects on liver gene transcription that are regulated by the temporal pattern of pituitary GH release, which is intermittent in male rats and nearly continuous in females. To investigate the influence of these GH secretory patterns on intracellular hepatocyte signaling, we compared the pattern of liver nuclear protein tyrosine phosphorylation in male and female rats. An Mr~93,000 polypeptide, p93, was found to be tyrosine phosphorylated to a high level in male but not female rats. GH, but not prolactin, rapidly stimulated p93 tyrosine phosphorylation in hypophysectomized rats. Intermittent plasma GH pulses triggered repeated p93 phosphorylation, while continuous GH exposure led to desensitization and a dramatic decline in liver nuclear p93. p93 was cross-reactive with two monoclonal antibodies raised to mammary Stat 5, whose tyrosine phosphorylation is stimulated by prolactin. Intermittent GH pulsation translocated liver Stat 5/p93 protein from the cytosol to the nucleus and also activated its DNA binding activity, as demonstrated using a mammary Stat 5-binding DNA element derived from the β-casein gene. p93 is thus a liver-expressed, Stat 5-related DNA binding protein that undergoes tyrosine phosphorylation and nuclear translocation in response to intermittent plasma GH stimulation and is proposed to be an intracellular mediator of the stimulatory effects of GH pulses on male-specific liver gene expression.

CYP2C12 is a steroid hydroxylase cytochrome P450 whose female-specific expression in adult rat liver is transcriptionally activated by the continuous plasma growth hormone (GH) profile characteristic of adult female rats. DNase I footprinting and gel mobility shift analysis of the 5′-flank of the CYP2C12gene were carried out to identify cis-acting elements and trans-acting factors that may contribute to the GH-regulated, sex-dependent transcription of this P450 gene. DNase I footprinting analysis revealed sex- and GH-regulated DNase I hypersensitivity sites at the boundaries of several protein binding sites detected along a 1560-nucleotide upstream segment of CYP2C12. Five distinct sites bound a novel continuous GH-regulated nuclear factor, GHNF, which is enriched in adult female and continuous GH-treated male liver nuclear extracts compared to untreated male liver nuclear extracts. Two other footprinted sites correspond to binding sites for the liver transcription factors C/EBP and albumin D element-binding protein and a third to an HNF1 binding site. A specific binding site for GHNF was also found in the 5′-proximal promoter of CYP2C11, an adult male-specific liver P450 gene, suggesting that GHNF may contribute to the down-regulation of that gene by continuous GH. GHNF was distinguished from the nuclear factors that bind to a GH response element upstream of the rat Spi 2.1 gene and is also distinct from the GH-activatable latent cytoplasmic transcription factors STAT 1, STAT 3, and STAT 5. These findings support the hypothesis that continuous GH-activated transcription of CYP2C12in adult female rat liver (a) involves the activation of a novel GH-regulated nuclear factor which binds to multiple sites along the 5′-flank of this cytochrome P450 gene, and (b) proceeds via a signaling pathway distinct from the GH pulse-activated STAT5 pathway proposed to induce CYP2C11and other male-expressed liver genes.

Intermittent plasma growth hormone (GH) pulses, which occur in male but not female rats, activate liver Stat 5 by a mechanism that involves tyrosine phosphorylation and nuclear translocation of this latent cytoplasmic transcription factor (Waxman, D. J., Ram, P. A., Park, S. H., and Choi, H. K.(1995) J. Biol. Chem.270, 13262-13270). We demonstrate that physiological levels of GH can also activate Stat 1 and Stat 3 in liver tissue, but with a dependence on the dose of GH and its temporal plasma profile that is distinct from Stat 5 and with a striking desensitization following a single hormone pulse that is not observed with liver Stat 5. GH activation of the two groups of Stats leads to their selective binding to DNA response elements upstream of the c-fosgene (c-sis-inducible enhancer element; Stat 1 and Stat 3 binding) and the β-casein gene (mammary gland factor element; liver Stat 5 binding). In addition to tyrosine phosphorylation, GH is shown to stimulate phosphorylation of these Stats on serine or threonine in a manner that either enhances (Stat 1 and Stat 3) or substantially alters (liver Stat 5) the binding of each Stat to its cognate DNA response element. These findings establish the occurrence of multiple, Stat-dependent GH signaling pathways in liver cells that can target distinct genes and thereby contribute to the diverse effects that GH and its sexually dimorphic plasma profile have on liver gene expression.

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The temperature dependence of the optical properties for amorphous silicon is studied at wavelengths of 632.8 and 752 nm. Both the refractive index and extinction coefficient increase linearly with temperature for 752 nm, while the refractive index decreases and the extinction coefficient increases for 632.8 nm. The rate of increase of the extinction coefficient at 632.8 nm is twice as much as that for 752 nm.

Effects of hydroxyl group (OH) in the gate insulator (GI) of AlOxformed by atomic layer deposition on the negative bias illumination stress (NBIS) stability of amorphous InGaZnO (a‐IGZO) thin film transistors (TFTs) by changing the deposition temperature (Tdep) of the AlOxGI are studied. There are no significant differences in the electrical properties and stabilities of each device, such as field effect mobility (μFE), subthreshold swing (S.S.), turn on voltage (Von), positive bias temperature stress (PBTS), and negative bias temperature stress (NBTS). Meanwhile, the NBIS stability is improved, resulting in Vonshift from −4.34 V to −2.48 V as the Tdepof the GI increased. This suggests that as the amount of OH increases in GI, more hole/and or ionized Votrapping sites are formed in the bulk GI. Based on the energy level in photoluminescence (PL) spectra of ALD AlOx, it is suggested OH related‐bulk trapping sites in ALD AlOxas the origin of non‐bridging oxygen hole center (NBOHC) in AlOxGI. Hydrogen (H) and hydroxyl group (OH) in the gate insulation layerare the major factors to affect NBIS instability of a‐IGZO TFTs. This is because new defects can generate at the deep level with increases of H and OH. In this regard, the first finding of the origin of hole and/or ionized Vodefects trapping sites are presented.

Rare earth doped materials, in the form of nanoparticles, have attracted extensive attention in photonic and biomedical applications. Separation of rare earth elements in a clean way has been also topic of great interest. Laser ablation has been actively examined to convert the rare earth containing bulk materials into functional nanoparticles as a potentially clean, efficient production method. However, elemental composition change during laser ablation based rare earth containing nanoparticle conversion process has not been studied extensively despite its significance. In this study, an ultraviolet nanosecond pulsed laser is used to ablate an erbium containing glass material with a major aim of tracking elemental composition in collected nanoparticles. The effect of laser fluence and laser beam spot is experimentally investigated by morphological, optical, spectroscopic, and elemental analyses. The results indicates the careful choice of laser parameters for the laser ablation can either preserve the elemental composition of bulk materials for applications dealing with rare earth containing materials or separate rare earth elements from bulk materials. In this study, the authors trace the elemental composition changeof a rare earth containing glass material upon conversion into nano sized particles by laser ablation process. The results indicates the careful choice of laser power and laser beam size can either preserve the elemental composition of bulk materials or separate rare earth elements from bulk materials.

We proposed in situ generation of cyclohexenyl peroxide as a surface oxidant in solution of CdSe quantum dots and verified it by monitoring emission wavelengths and intensities of CdSe and CdSe–ZnS in cyclohexene, respectively. A clear 80 nm blue shift in the emission was observed in CdSe–ZnS over 3 mon due to the slow diffusion of the oxidant, while a 10 nm shift was in CdSe for 24 h.

Metal organometallic carboxylates with unusual polyhedral and rectangular shapes have been prepared by the reaction of 1,1′-ferrocenedicarboxylic acid (H2FDCA) with ZnIIand CuIIto give [Zn6O2(FDCA)5(H2O)(DMF)]·(DMF)4(1), [Zn8O4(FDCA)6(H2O)3]·(DMA)4·(H2O)2(2), and [Cu4(FDCA)2] (3), respectively (DMF = N,N′-dimethylformamide; DMA = N,N′-dimethylacetoamide). SQUID data of zinc compounds show that iron ions of the ferrocene moieties in the compounds exhibit antiferromagnetic coupling.

We have succeeded in assembling a new trigonal aryne ligand, triphenylene-2,6,10-tricarboxylic acid (H3TTCA) with metal ions to give M3(TTCA)2·6DMF·7H2O (M = Zn2+and Cd2+) (DMF = N,N-dimethylformamide), which networks show non-interpenetrated porous metal carboxylate frameworks and belong to a novel doubly-interwoven SrSi2topology.

An octanuclear oxomolybdenum(V) cluster compound [Mo8O16Cl2(OCH3)6(HOCH3)4] was prepared from the reaction of oxomolybdenum(V) chloride and the potassium salt of triethanolamine in methanol. The complex was used to prepare Sr2FeMoO6, which shows a very high negative magnetoresistance of 33% with a magnetic field of 0.8 T at 12 K.

An air-stable iron cluster alkoxide complex Na2[Fe6(OCH2CH2OCH3)18(µ6-O)] was prepared from the reaction of iron(III) chloride and sodium 2-methoxyethoxide. The complex was used to prepare Sr2FeMoO6, which spin-coated film shows a very high positive magnetoresistance of 25% with a magnetic field of 0.8 T at 300 K.

A patient with a brain tumor and seizures who was receiving maintenance doses of phenytoin was given chloramphenicol on three occasions. Her neurological status was both complicated and obscured by the reoccurrence of phenytoin intoxication. Retrospective drug analysis showed a marked elevation of serum concentrations of phenytoin during each course of chloramphenicol.(JAMA 237:2630-2631, 1977)