Enhanced Self-Assembly of Crystalline, Large-Area, and Periodicity-Tunable TiO2 Nanotube Arrays on Various Substrates.

Due to their superior physical properties, titanium dioxide (TiO2) nanotube arrays are one of the most investigated nanostructure systems in materials science until now. However, it is still a great challenge to achieve damage-free techniques to realize controllable, cost-effective, and high-performance TiO2 nanotube arrays on both rigid and flexible substrates for different technological applications. In this work, we demonstrate a unique strategy to achieve self-assemble crystalline, large-area, and regular TiO2 nanotube arrays on various substrates via hybrid combination of conventional semiconductor processes. Besides the usual applications of TiO2 as carrier transport layers in thin-film electronic devices, we demonstrate that the periodic TiO2 nanotube arrays can show the effect of optical grating with large-area uniformity. Specifically, the fabricated nanotube geometries, such as the tube height, pitch, diameter, and wall thickness, as well as the crystallinity can be reliably controlled by varying the processing conditions. More importantly, utilizing these nanotube arrays in perovskite solar cells can further enhance the optical absorption, leading to improved power conversion efficiency. In contrast to other typical template-assisted fabrication approaches, we employ a soft template here, which would enable the construction of nanotube arrays without any significant damage associated with template removal. Furthermore, without the thermal restriction of underlying substrates, these crystalline nanotube arrays can be transferred to mechanically flexible substrates by a simple one-step method, which can expedite these nanotubes for potential utilization in other application domains.

Modulating Electrical Properties of InAs Nanowires via Molecular Monolayers.

In recent years, InAs nanowires have been demonstrated with the excellent electron mobility as well as highly efficient near-infrared and visible photoresponse at room temperature. However, due to the presence of a large amount of surface states that originate from the unstable native oxide, the fabricated nanowire transistors are always operated in the depletion mode with degraded electron mobility, which is not energy-efficient. In this work, instead of the conventional inorganic sulfur or alkanethiol surface passivation, we employ aromatic thiolate (ArS(-))-based molecular monolayers with controllable molecular design and electron density for the surface modification of InAs nanowires (i.e., device channels) by simple wet chemistry. More importantly, besides reliably improving the device performances by enhancing the electron mobility and the current on-off ratio through surface state passivation, the device threshold voltage (VTh) can also be modulated by varying the para-substituent of the monolayers such that the molecule bearing electron-withdrawing groups would significantly shift the VTh towards the positive region for the enhancement mode device operation, in which the effect has been quantified by density functional theory calculations. These findings reveal explicitly the efficient modulation of the InAs nanowires' electronic transport properties via ArS(-)-based molecular monolayers, which further elucidates the technological potency of this ArS(-) surface treatment for future nanoelectronic device fabrication and circuit integration.

Androgen deprivation therapy, diabetes and poor physical performance status increase fracture risk in Chinese men treated for prostate cancer.

We investigated the fracture risk after androgen deprivation therapy (ADT) for prostate cancer in the Chinese population. All Chinese prostate cancer patients who were treated primarily by radical prostatectomy or radiotherapy, with or without further ADT, from year 2000 to 2009 were reviewed. We compared the fracture risk in patients who were given ADT (ADT group) with those who were not given any ADT (non-ADT group). Potential risk factors including age, diabetes mellitus, hypertension, hyperlipidemia, ischemic heart disease and performance status were reviewed. The fracture risk was analyzed with Kaplan-Meier and multivariate Cox regression analyses. Our cohort consisted of 200 patients in the non-ADT group and 252 patients in the ADT group. The ADT group was shown to have higher fracture risk (p = 0.036) upon Kaplan-Meier analysis. Upon multivariate Cox regression analyses, diabetes mellitus (HR 4.39, 95% CI 1.08-17.83, p = 0.039), poor performance status (HR 3.14, 95% CI 1.24-8.00, p = 0.016) and the use of ADT (HR 4.89, 95% CI 1.03-23.17, p = 0.045) were associated with increased fracture risk. In conclusion, the fracture risk should be considered while deciding on ADT in Chinese men, especially in diabetic patients with poor performance status.

Risk of cardiovascular thrombotic events after surgical castration versus gonadotropin-releasing hormone agonists in Chinese men with prostate cancer.

We investigated the cardiovascular thrombotic risk after surgical castration (SC) versus gonadotropin-releasing hormone agonists (GnRHa) in Chinese men with prostate cancer. All Chinese prostate cancer patients who were treated with SC or GnRHa from year 2000 to 2009 were reviewed and compared. The primary outcome was any new-onset of cardiovascular thrombotic events after SC or GnRHa, which was defined as any event of acute myocardial infarction or ischemic stroke. The risk of new-onset cardiovascular thrombotic event was compared between the SC group and the GnRHa group using Kaplan-Meier method. Multivariate Cox regression analysis was performed to adjust for other potential confounding factors. A total of 684 Chinese patients was included in our study, including 387 patients in the SC group and 297 patients in the GnRHa group. The mean age in the SC group (75.3 ± 7.5 years) was significantly higher than the GnRHa group (71.8 ± 8.3 years) (P < 0.001). There was increased risk of new cardiovascular thrombotic events in the SC group when compared to the GnRHa group upon Kaplan-Meier analysis (P = 0.014). Upon multivariate Cox regression analysis, age (hazard ratio [HR] 1.072, 95% confidence interval [CI] 1.04-1.11, P< 0.001), hyperlipidemia (HR 2.455, 95% CI 1.53-3.93, P< 0.001), and SC (HR 1.648, 95% CI 1.05-2.59, P= 0.031) were significant risk factors of cardiovascular thrombotic events. In conclusion, SC was associated with increased risk of cardiovascular thrombotic events when compared to GnRHa. This is an important aspect to consider while deciding on the method of androgen deprivation therapy, especially in elderly men with known history of hyperlipidemia.

Risk of new-onset diabetes after androgen deprivation therapy for prostate cancer in the Asian population.

BACKGROUND: The associations of androgen deprivation therapy (ADT) with its adverse events in the Asian population remained largely unknown. We investigated the risk of new-onset diabetes mellitus (DM) after ADT for prostate cancer in the Asian population. METHODS: All prostate cancer patients who were treated primarily with radical prostatectomy or radiotherapy, with or without further ADT from 2000 to 2009 were reviewed. Clinical parameters including age, clinical T stage, Gleason score, hypertension, dyslipidemia, impaired fasting glucose, ischemic heart disease, history of stroke, new-onset DM, follow-up duration, form and duration of ADT were reviewed. The risk of DM after ADT was analyzed with Kaplan-Meier method and multivariate Cox regression analysis. RESULTS: A total of 388 patients were included, consisting of 169 patients in the non-ADT group and 219 patients in the ADT group. Upon Kaplan-Meier analysis, the ADT group had a higher risk of new-onset DM (P = 0.011). Upon multivariate Cox regression analysis, dyslipidemia (HR 2.32, 95% CI 1.07-5.00, P = 0.032), impaired fasting glucose (HR 5.92, 95% CI 1. 2.27-15.45, P < 0.001) and the use of ADT in the form of GnRH agonist (HR 3.34, 95% CI 1.19-9.39, P = 0.022) and bilateral orchiectomy (HR 6.49, 95% CI 1.48-28.55, P = 0.013) were associated with increased risk of new-onset DM. CONCLUSIONS: There was increased risk of new-onset DM after ADT for prostate cancer in the Asian population. Regular screening of DM can be considered after the initiation of ADT, especially in patients with known history of dyslipidemia and impaired fasting glucose.

Risk of acute myocardial infarction after androgen-deprivation therapy for prostate cancer in a Chinese population.

OBJECTIVE: To investigate the risk of acute myocardial infarction (AMI) after androgen-deprivation therapy (ADT) for prostate cancer in a Chinese population. PATIENTS AND METHODS: All Chinese patients with prostate cancer who were treated primarily with radical prostatectomy or radiotherapy, with or without further ADT at our hospital from the year 2000 to 2009 were retrospectively reviewed. We compared the risk of AMI in the patients who were given further ADT (ADT group) with those who were not given any ADT (non-ADT group). Potential risk factors of AMI including age, diabetes mellitus, hypertension, hyperlipidaemia, history of stroke, ischaemic heart disease, Eastern Cooperative Oncology Group Performance Status (ECOG PS) and duration of ADT were reviewed. The risk of AMI after ADT was first analysed using the Kaplan-Meier method, followed by Cox regression analyses including the potential risk factors mentioned. RESULTS: In all, 452 patients were included, with 200 patients in the non-ADT group and 252 patients in the ADT group. The mean (sd) age was 68.2 (5.9) years in the non-ADT group and 69.5 (6.5) years in the ADT group, and the difference was statistically significant (P = 0.031). There were no significant differences in their pre-existing medical conditions or ECOG PS. The ADT group was associated with an increased risk of AMI when compared with the non-ADT group (P = 0.004) upon Kaplan-Meier analysis. Upon multivariate Cox regression analysis, hyperlipidaemia, poor ECOG PS and the use of ADT were the only three significant factors that were associated with increased risk of developing new AMI. CONCLUSIONS: There was increased risk of AMI after ADT for prostate cancer in a Chinese population. Hyperlipidaemia and poor ECOG PS were also significant risk factors for developing AMI. The risk of AMI should be considered when deciding on ADT, especially in patients with history of hyperlipidaemia and relatively poor ECOG PS.

Polymer-confined colloidal monolayer: a reusable soft photomask for rapid wafer-scale nanopatterning.

We demonstrate the repeated utilization of self-assembled colloidal spheres for rapid nanopattern generations. Highly ordered micro-/nanosphere arrays were interlinked and confined by a soft transparent polymer (polydimethylsiloxane, PDMS), which can be used as light-focusing elements/photomasks for area-selective exposures of photoresist in contact. Because of the stiffness of the colloidal spheres, the photomasks do not encounter feature-deformation problems, enabling reliable production of highly uniform patterns over large areas. The geometrical feature of the patterns, including the size, pitch, and even the shape, can be finely tuned by adjusting the mask design and exposure time. The obtained patterns could be used as deposition or etching mask, allowing easy pattern transfer for various applications.

Surfactant-assisted chemical vapour deposition of high-performance small-diameter GaSb nanowires.

Although various device structures based on GaSb nanowires have been realized, further performance enhancement suffers from uncontrolled radial growth during the nanowire synthesis, resulting in non-uniform and tapered nanowires with diameters larger than few tens of nanometres. Here we report the use of sulfur surfactant in chemical vapour deposition to achieve very thin and uniform GaSb nanowires with diameters down to 20 nm. In contrast to surfactant effects typically employed in the liquid phase and thin-film technologies, the sulfur atoms contribute to form stable S-Sb bonds on the as-grown nanowire surface, effectively stabilizing sidewalls and minimizing unintentional radial nanowire growth. When configured into transistors, these devices exhibit impressive electrical properties with the peak hole mobility of ~200 cm(2 )V(-1 )s(-1), better than any mobility value reported for a GaSb nanowire device to date. These factors indicate the effectiveness of this surfactant-assisted growth for high-performance small-diameter GaSb nanowires.

Inflammatory myofibroblastic tumors of the urinary bladder: a systematic review.

We systemically reviewed the literature on inflammatory myofibroblastic tumors (IMTs) of the urinary bladder and compared between anaplastic lymphoma kinase (ALK)-positive and ALK-negative IMTs. An extensive search of the literature was performed in Medline and Web of Science using the following terms: "inflammatory myofibrolastic tumor," "inflammatory pseudotumor," and "bladder." A manual search was also performed using the web-based search engine Google Scholar. Reference lists of the retrieved articles were reviewed for other relevant studies. Patients' and disease characteristics of each individual case were reviewed. Further analyses were performed to compare between ALK-positive and ALK-negative IMTs. Forty-one studies were identified, and 182 patients were included for review and subsequent analyses. Of the IMTs, 65% were ALK-positive. Local tumor recurrence rate was 4%, and no cases of distant metastases have been reported. Compared with ALK-negative IMTs, ALK-positive IMTs had a female predilection with a sex ratio (male:female) of 1:1.67 (P = .048). ALK-positive IMTs also appeared to occur in younger patients (P = .072). No significant differences were noted in terms of their clinical presentations and histologic features. On immunohistochemical staining, ALK-positive IMTs had more positive results for desmin (P = .042) and p53 (P = .05), and more negative results for clusterin (P = .003). In summary, ALK-positive IMTs of the urinary bladder had a female predilection, appeared to occur more frequently in younger patients, and had different immunohistochemical staining patterns when compared with ALK-negative IMTs. Regardless of its ALK status, IMT of the urinary bladder has a good prognosis after surgical resection.

Rational design of inverted nanopencil arrays for cost-effective, broadband, and omnidirectional light harvesting.

Due to the unique optical properties, three-dimensional arrays of silicon nanostructures have attracted increasing attention as the efficient photon harvesters for various technological applications. In this work, instead of dry etching, we have utilized our newly developed wet anisotropic etching to fabricate silicon nanostructured arrays with different well-controlled geometrical morphologies, ranging from nanopillars, nanorods, and inverted nanopencils to nanocones, followed by systematic investigations of their photon-capturing properties combining experiments and simulations. It is revealed that optical properties of these nanoarrays are predominantly dictated by their geometrical factors including the structural pitch, material filling ratio, and aspect ratio. Surprisingly, along with the proper geometrical design, the inverted nanopencil arrays can couple incident photons into optical modes in the pencil base efficiently in order to achieve excellent broadband and omnidirectional light-harvesting performances even with the substrate thickness down to 10 µm, which are comparable to the costly and technically difficult to achieve nanocone counterparts. Notably, the fabricated nanopencils with both 800 and 380 nm base diameters can suppress the optical reflection well below 5% over a broad wavelength of 400-1000 nm and a wide angle of incidence between 0 and 60°. All these findings not only offer additional insight into the light-trapping mechanism in these complex 3D nanophotonic structures but also provide efficient broadband and omnidirectional photon harvesters for next-generation cost-effective ultrathin nanostructured photovoltaics.

Crystalline GaSb nanowires synthesized on amorphous substrates: from the formation mechanism to p-channel transistor applications.

In recent years, because of the narrow direct bandgap and outstanding carrier mobility, GaSb nanowires (NWs) have been extensively explored for various electronics and optoelectronics. Importantly, these p-channel nanowires can be potentially integrated with n-type InSb, InAs, or InGaAs NW devices via different NW transfer techniques to facilitate the III-V CMOS technology. However, until now, there have been very few works focusing on the electronic transport properties of GaSb NWs. Here, we successfully demonstrate the synthesis of crystalline, stoichiometric, and dense GaSb NWs on amorphous substrates, instead of the commonly used III-V crystalline substrates, InAs, or GaAs NW stems as others reported. The obtained NWs are found to grow via the VLS mechanism with a narrow distribution of diameter (220 ± 50 nm) uniformly along the entire NW length (>10 µm) with minimal tapering and surface coating. Notably, when configured into FETs, the NWs exhibit respectable electrical characteristics with the peak hole mobility of ~30 cm(2) V(-1) s(-1) and free hole concentration of ~9.7 × 10(17) cm(-3). All these have illustrated the promising potency of such NWs directly grown on amorphous substrates for various technological applications, as compared with the conventional MOCVD-grown GaSb NWs.

Carbon doping of InSb nanowires for high-performance p-channel field-effect-transistors.

Due to the unique physical properties, small bandgap III-V semiconductor nanowires such as InAs and InSb have been extensively studied for the next-generation high-speed and high-frequency electronics. However, further CMOS applications are still limited by the lack of efficient p-doping in these nanowire materials for high-performance p-channel devices. Here, we demonstrate a simple and effective in situ doping technique in the solid-source chemical vapor deposition of InSb nanowires on amorphous substrates employing carbon dopants. The grown nanowires exhibit excellent crystallinity and uniform stoichiometric composition along the entire length of the nanowires. More importantly, the versatility of this doping scheme is illustrated by the fabrication of high-performance p-channel nanowire field-effect-transistors. High electrically active carbon concentrations of ~7.5 × 10(17) cm(-3) and field-effect hole mobility of ~140 cm(2) V(-1) s(-1) are achieved which are essential for compensating the electron-rich surface layers of InSb to enable heavily p-doped and high-performance device structures. All these further indicate the technological potency of this in situ doping technique as well as p-InSb nanowires for the fabrication of future CMOS electronics.

Ruthenium complexes containing 2-(2-nitrosoaryl)pyridine: structural, spectroscopic, and theoretical studies.

Ruthenium complexes containing 2-(2-nitrosoaryl)pyridine (ON(^)N) and tetradentate thioether 1,4,8,11-tetrathiacyclotetradecane ([14]aneS4), [Ru(ON(^)N)([14]aneS4)](2+) [ON(^)N = 2-(2-nitrosophenyl)pyridine (2a), 10-nitrosobenzo[h]quinoline (2b), 2-(2-nitroso-4-methylphenyl)pyridine, (2c), 2-(2-nitrosophenyl)-5-(trifluoromethyl)pyridine (2d)] and analogues with the 1,4,7-trithiacyclononane ([9]aneS3)/tert-butylisocyanide ligand set, [Ru(ON(^)N)([9]aneS3)(C≡N(t)Bu)](2+) (4a and 4b), have been prepared by insertion of a nitrosonium ion (NO(+)) into the Ru-aryl bond of cyclometalated ruthenium(II) complexes. The molecular structures of the ON(^)N-ligated complexes 2a and 2b reveal that (i) the ON(^)N ligands behave as bidentate chelates via the two N atoms and the bite angles are 86.84(18)-87.83(16)° and (ii) the Ru-N(NO) and N-O distances are 1.942(5)-1.948(4) and 1.235(6)-1.244(5) Å, respectively. The Ru-N(NO) and N-O distances, together with ν(N═O), suggest that the coordinated ON(^)N ligands in this work are neutral moiety (ArNO)(0) rather than monoanionic radical (ArNO)(•-) or dianion (ArNO)(2-) species. The nitrosated complexes 2a-2d show moderately intense absorptions centered at 463-484 nm [ε(max) = (5-6) × 10(3) dm(3) mol(-1) cm(-1)] and a clearly discriminable absorption shoulder around 620 nm (ε(max) = (6-9) × 10(2) dm(3) mol(-1) cm(-1)), which tails up to 800 nm. These visible absorptions are assigned as a mixing of d(Ru) → ON(^)N metal-to-ligand charge-transfer and ON(^)N intraligand transitions on the basis of time-dependent density functional theory (TD-DFT) calculations. The first reduction couples of the nitrosated complexes range from -0.53 to -0.62 V vs Cp(2)Fe(+/0), which are 1.1-1.2 V less negative than that for [Ru(bpy)([14]aneS4)](2+) (bpy = 2,2'-bipyridine). Both electrochemical data and DFT calculations suggest that the lowest unoccupied molecular orbitals of the nitrosated complexes are ON(^)N-centered. Natural population analysis shows that the amount of positive charge on the Ru centers and the [Ru([14]aneS4)] moieties in 2a and 2b is larger than that in [Ru(bpy)([14]aneS4)](2+). According to the results of the structural, spectroscopic, electrochemical, and theoretical investigations, the ON(^)N ligands in this work have considerable π-acidic character and behave as better electron acceptors than bpy.