Spatial range of the plasmonic Dicke effect in an InGaN/GaN multiple quantum well structure

The plasmonic Dicke effect means a cooperative emission mechanism of multiple light emitters when they are simultaneously coupled with the same surface plasmon (SP) mode of a metal nanostructure to achieve a higher collective emission efficiency. Here, we compare the enhancements of emission efficiency among a series of SP-coupled InGaN/GaN quantum-well (QW) structures of different QW period numbers to show an emission behavior consistent with the plasmonic Dicke effect. The relative enhancement of overall emission efficiency increases with QW period number until it reaches a critical value, beyond which the enhancement starts to decrease. This critical QW period number corresponds to the effective depth range of the plasmonic Dicke effect in a multiple-QW system. It also represents an optimized QW structure for maximizing the SP coupling effect. Internal quantum efficiency and time-resolved photoluminescence are measured for comparing the enhanced emission efficiencies of blue and green QW structures with different QW period numbers through SP coupling induced by surface Ag nanoparticles.

Important role of surface plasmon coupling with the quantum wells in a surface plasmon enhanced color-converting structure of colloidal quantum dots on quantum wells

To improve the color-conversion efficiency based on a quantum-well (QW) light-emitting diode (LED), a more energy-saving strategy is needed to increase the energy transfer efficiency from the electrical input power of the LED into the emission of over-coated color-converter, not just from LED emission into converted light. In this regard, the efficiency of energy transfer of any mechanism from LED QW into the color-converter is an important issue. By overlaying blue-emitting QW structures and GaN templates with both deposited metal nanoparticles (DMNPs) and color-converting quantum dot (QD) linked synthesized metal nanoparticles (SMNPs) of different localized surface plasmon (LSP) resonance wavelengths for producing multiple surface plasmon (SP) coupling mechanisms with the QW and QD, we study the enhancement variations of their internal quantum efficiencies and photoluminescence decay times. By comparing the QD emission efficiencies between the samples with and without QW, one can observe the advantageous effect of QW coupling with LSP resonances on QD emission efficiency. Also, with the LSP resonance wavelengths of both DMNPs and SMNPs close to the QW emission wavelength for producing strong SP coupling with the QW and hence QD absorption, a higher QD emission or color-conversion efficiency can be obtained.

Prevalence, subtypes, and correlates of nocturia in the symptoms of Lower Urinary Tract Dysfunction Research Network cohort

AIMS

We determined the prevalence, severity, and correlates of nocturia in a large clinical cohort of patients.

METHODS

Patients presenting with lower urinary tract symptoms (LUTS) completed 3-day bladder diaries. Nocturia was quantified based on the mean number of nighttime voids documented over the 3 days. Nocturia subtypes (global polyuria, nocturnal polyuria [NP], reduced global bladder capacity, and reduced nocturnal bladder capacity) were assessed. Bother due to nocturia was measured by the LUTS Tool. Sleep quality was assessed with the Patient-Reported Outcomes Measurement Information System Sleep Scale. Multivariable multinomial regression was used to explore patient characteristics associated with nocturia.

RESULTS

In 502 participants with analyzable diaries (285 men and 217 women), the mean number of nocturia episodes over 3 days was 0 in 103 (20.5%), >0 to <1 in 151 (20.1%), 1 to <2 in 165 (32.9%), and ≥2 in 83 (16.5%). Sixty-seven percent of the participants with nocturia ≥1 reported significant bother from their nocturia. NP was the most common nocturia subtype and was present in 17% of those with nocturia = 0, 40% of those with nocturia >0 to <1, 65% of those with nocturia 1 to <2%, and 77% with nocturia 2+. Higher degrees of nocturia were associated with male sex, greater sleep disturbance, and a higher likelihood of exhibiting multiple nocturia subtypes.

CONCLUSIONS

Nocturia ≥1 occurred in 49% of LUTS patients and caused significant bother in the majority of them. The most common subtype was NP, but a substantial proportion of patients exhibited additional characteristics.

Theoretical analysis of a white-light LED array based on a GaN nanorod structure

Based on the experimentally demonstrated In content distribution in the InGaN/GaN quantum wells on a two-section GaN nanorod (NR) sidewall, a white-light light-emitting diode (LED) without phosphor is designed and simulated. Following the dependencies of the In diffusion length and incorporation ratio on NR geometric variables of a theoretical model, the height, radius, and tapering section geometry of the GaN NR are designed for controlling the relative intensities of a blue and a yellow emission component to mix into white light. The higher-In upper section of the NR is first excited to emit a relatively stronger yellow component when injection current is low. As the injection current increases, more current spreads into the lower-In lower section, eventually leading to a stronger blue emission component. The proposed NR LED structure provides an alternative solution for phosphor-free white-light generation.

Emission behaviors of colloidal quantum dots linked onto synthesized metal nanoparticles

With two different residual surfactants, four different metal nanoparticles (NPs), including two Au NPs and two Ag NPs are synthesized for linking with red-emitting CdZnSeS/ZnS colloidal quantum dots (QDs) to enhance QD emission efficiency. Those metal NPs are first connected with amino polyethylene glycol thiol of different molecular weights to avoid aggregation and make them positively charged. They can attract negatively charged QDs for inducing surface plasmon (SP) coupling such that either QD absorption or emission and hence overall color conversion efficiency can be enhanced. The enhancement of QD emission efficiency is evaluated through the comparison of time-resolved photoluminescence behaviors under different QD linkage conditions. Such results are confirmed by the measurement of the emission quantum efficiency of QD. It is found that by linking QDs onto Ag NPs, the QD emission efficiency is more enhanced, when compared with Au NPs. Also, depending on the synthesis process, the residual surfactant of citrate leads to a relatively large increment in QD emission efficiency, when compared to the surfactant of cetrimonium chloride. A more enhanced QD emission efficiency is caused by a higher QD linkage capability and a stronger SP coupling effect.

NiS2 nanoparticles anchored on open carbon nanohelmets as an advanced anode for lithium-ion batteries

Low intrinsic conductivity and large volume expansion seriously restrict the efficient lithium storage performance of metal sulfides. Here, we fabricate a hybrid material of NiS₂ nanoparticles/carbon nanohelmets (NiS₂/CNHs) to address the above issues. As an anode material in lithium-ion batteries, NiS₂/CNHs exhibit excellent cycling stability (490 mA h g^-1 after 3000 cycles at 5 A g^-1) and rate properties (412 mA h g^-1 at 10 A g^-1), outperforming other NiS _x -based anode materials. These remarkable performances originate from the three-dimensional helmet-like integrated architecture of NiS₂/CNHs, which reduces the electrode resistance due to the tight combination between NiS₂ and CNHs, provides efficient diffusion paths for the electrolyte and Li⁺ owing to the amorphous nanoporous carbon structure, and significantly mitigates the aggregation and buffers the large volumetric expansion of NiS₂ nanoparticles upon long-term cycling thanks to the open three-dimensional architecture and well-dispersed NiS₂ nanoparticles on it.

Symptom Based Clustering of Men in the LURN Observational Cohort Study

PURPOSE

Conventional classification of patients with lower urinary tract symptoms into diagnostic categories based on a predefined symptom complex or predominant symptom appears inadequate. This is due to the frequent presentation of patients with multiple urinary symptoms which could not be perfectly categorized into traditional diagnostic groups. We used a novel clustering method to identify subtypes of male patients with lower urinary tract symptoms based on detailed multisymptom information.

MATERIALS AND METHODS

We analyzed baseline data on 503 care seeking men in the LURN (Symptoms of Lower Urinary Tract Dysfunction Research Network) Observational Cohort Study. Symptoms and symptom severity were assessed using the LUTS (Lower Urinary Tract Symptoms) Tool and the AUA SI (American Urological Association Symptom Index), which include a total of 52 questions. We used a resampling based consensus clustering algorithm to identify patient subtypes with distinct symptom signatures.

RESULTS

Four distinct symptom clusters were identified. The 166 patients in cluster M1 had predominant symptoms of frequency, nocturia, hesitancy, straining, weak stream, intermittency and incomplete bladder emptying suggestive of bladder outlet obstruction. The 93 patients in cluster M2 mainly endorsed post-micturition symptoms (eg post-void dribbling and post-void leakage) with some weak stream. The 114 patients in cluster M3 reported mostly urinary frequency without incontinence. The 130 patients in cluster M4 reported severe frequency, urgency and urgency incontinence. Most other urinary symptoms statistically differed between cluster pairs. Patient reported outcomes of bowel symptoms, mental health, sleep dysfunction, erectile function and urological pain significantly differed across the clusters.

CONCLUSIONS

We identified 4 data derived clusters among men seeking care for lower urinary tract symptoms. The clusters differed from traditional diagnostic categories. Further subtype refinement will be done to incorporate clinical data and nonurinary patient reported outcomes.

Color conversion efficiency enhancement of colloidal quantum dot through its linkage with synthesized metal nanoparticle on a blue light-emitting diode

Four surface-modified and, hence, positively charged metal nanoparticles (NPs) of different localized surface plasmon (LSP) resonance wavelengths are synthesized for linking with negatively charged, red-emitting colloidal CdZnSeS/ZnS quantum dots (QDs) on the top surface of a blue-emitting InGaN/GaN quantum well (QW) light-emitting diode (LED) through electro-static force. The metal NP-QD linkage leads to a short distance between them for producing their strong surface plasmon (SP) coupling, such that QD absorption and emission can be enhanced. Meanwhile, the small p-GaN thickness in the LED results in strong SP coupling between the LSP resonance of metal NP and the QWs of the LED, leading to enhanced QW emission and, hence, stronger QD excitation. All those factors together result in the increase of the color conversion efficiency of the QD.

Longitudinal changes in symptom-based female and male LUTS clusters

AIMS

Lower urinary tract symptoms (LUTS) are diverse in type and variable in severity. We examined symptom change within the Symptoms of the Lower Urinary Tract Dysfunction Research Network (LURN) Observational Cohort study identified clusters over time and tested associations with treatments received.

METHODS

Patient-reported LUTS and treatment data were collected at multiple time points between baseline and 12 months from the LURN Observational Cohort study. LUTS severity scores were calculated to summarize changes in symptom reporting over time in previously identified LURN clusters. Repeated measures linear regression models tested adjusted associations between cluster membership and severity scores.

RESULTS

Four-hundred seventeen men and 396 women were classified into improved, unchanged, and worsened symptoms between baseline and 12 months (men: 44.1%, 40.5%, and 15.3%; women: 55.8%, 33.1%, 11.1%, respectively). Improvement in LUTS severity scores varied by cluster (estimated adjusted mean change from baseline range: -.04 change in standard deviations of severity scores (ΔSD) to -.67 ΔSD). Prostate surgery was associated with improved severity scores (-.63 ΔSD) in men, while stress incontinence surgery was associated with improved severity scores (-.88 ΔSD) in women.

CONCLUSION

Symptom improvement varied by cluster indicating response to therapy differs amongst subtypes of patients with LUTS. The differential improvement of patients in clusters suggests mechanistic differences between clusters and may aid in selecting more targeted treatments in the future.

The Distribution of Post-Void Residual Volumes in People Seeking Care in the Symptoms of Lower Urinary Tract Dysfunction Network Observational Cohort Study With Comparison to Asymptomatic Populations

OBJECTIVE

To describe the distribution of post-void residual (PVR) volumes across patients with and without lower urinary tract symptoms (LUTS) and examine relationships between self-reported voiding symptoms, storage symptoms, and PVR.

METHODS

PVR and demographic data were obtained from the Symptoms of Lower Urinary Tract Dysfunction Research Network (LURN) observational cohort study. Self-reported symptoms were collected using the American Urological Association Symptom Index and the LUTS Tool. PVR values were obtained from 2 other cohorts: living kidney donors with unknown LUTS from the Renal and Lung Living Donors Evaluation Study (RELIVE), and continent women in the Establishing the Prevalence of Incontinence (EPI) study, a population-based study of racial differences in urinary incontinence prevalence.

RESULTS

Across the 3 studies, median PVRs were similar: 26 mL in LURN (n = 880, range 0-932 mL), 20 mL in EPI (n = 166, range 0-400 mL), and 14 mL in RELIVE (n = 191, range 0-352 mL). In LURN, males had 3.6 times higher odds of having PVR > 200 mL (95% CI = 1.72-7.48). In RELIVE, median PVR was significantly higher for males (20 mL vs 0 mL, P= .004). Among women, only the intermittency severity rating was associated with a probability of an elevated PVR. Among men, incomplete emptying and burning severity rating were associated with a higher odds of elevated PVR, but urgency severity ratings were associated with lower odds of elevated PVR.

CONCLUSION

Care-seeking patients have PVRs similar to those in people with unknown history of LUTS (RELIVE) and without self-reported LUTS (EPI). Although PVR was correlated with voiding symptoms, the mean differences only explain ∼2% of the variance.

Are three-day voiding diaries feasible and reliable? Results from the Symptoms of Lower Urinary Tract Dysfunction Research Network (LURN) cohort

AIMS

The aims of this study were to assess the completeness of voiding diaries in a research context and to correlate diary data with patient-reported questionnaires.

METHODS

Men and women enrolled in the Symptoms of Lower Urinary Tract Dysfunction Research Network (LURN) were given a 3-day voiding and fluid-intake diary to fill-out. Diaries were assessed for completeness and intake-output imbalances. They were assigned to one of four categories based on a percentage of missing data and fluid imbalance: no diary submitted, unusable (>40% missing void or intake volumes, or unphysiological fluid imbalance), usable but not complete, and complete.

RESULTS

A total of 1064 participants were enrolled and 85% (n = 902) returned the bladder diary. Of the diaries returned, 94% (n = 845) had data on three separate days, 87% (n = 786) had no missing intake volumes, 61% (n = 547) had no missing voided volumes, and 70% (n = 635) had a fluid imbalance within 3 L across the 3-day time period, resulting in 50% (n = 448) of participants with 100% complete diaries. Younger age was associated with a higher likelihood of not submitting a diary, or submitting an unusable diary. Women had a higher likelihood of submitting an unusable diary or a usable but incomplete diary.

CONCLUSION

Overall, 50% of LURN participants returned voiding diaries with perfectly complete data. Incomplete data for voided volumes was the most common deficiency. There was only a moderate correlation between diary data and questionnaire responses, indicating that diaries are a source of unique information.

Simulation study on light color conversion enhancement through surface plasmon coupling

A theoretical model together with a numerical algorithm of surface plasmon (SP) coupling are built for simulating SP-enhanced light color conversion from a shorter-wavelength radiating dipole (representing a quantum well - QW) into a longer-wavelength one (representing a quantum dot - QD) through QD absorption at the shorter wavelength. An Ag nanoparticle (NP) located between the two dipoles is designed for producing strong SP couplings simultaneously at the two wavelengths. At the QW emission wavelength, SP couplings with the QW and QD dipoles lead to the energy transfer from the QW into the QD and hence the absorption enhancement of the QD. At the QD emission wavelength, SP coupling with the excited QD dipole results in the enhancement of QD emission efficiency. The combination of the SP-induced effects at the two wavelengths leads to the increase of overall color conversion efficiency. The color conversion efficiencies in using Ag NPs of different geometries or SP resonance behaviors for producing different QD absorption and emission enhancement levels are compared.

[Regulation mechanism of E2F1 transcription factor on M2 macrophages in full-thickness skin defect wounds of mice]

Objective: To explore the regulatory mechanism of E2F1 transcription factor on M2 macrophages in full-thickness skin defect wounds of mice. Methods: E2F1 gene knockout heterozygotes C57BL/6 mice and wild-type C57BL/6 mice were introduced and self-reproduced. Two weeks after birth, E2F1 gene knockout homozygotes mice and wild-type mice were identified by polymerase chain reaction (PCR). Twelve identified 6-8 weeks old male E2F1 gene knockout homozygotes C57BL/6 mice and wild-type C57BL/6 mice were selected respectively according to the random number table and set as E2F1 gene knockout group and wild-type group. A full-thickness skin defect wound was made on the back of each mouse. On post injury day (PID) 2 and 7, 6 mice in each group were selected according to the random number table and sacrificed, and the wound tissue was excised. The expression of CD68 and CD206 double positive M2 macrophages was observed by immunofluorescence method, and the percentage of CD206 positive cells was calculated. The protein expression of CD206 was detected by Western blotting. The mRNA expression of arginase 1 was detected by real-time fluorescent quantitative reverse transcription PCR (RT-PCR). Wound tissue specimens of the two groups on PID 7 were obtained, and the protein and mRNA expressions of peroxisome proliferator-activated receptor gamma (PPAR-γ) were detected by Western blotting and real-time fluorescent quantitative RT-PCR respectively. The above-mentioned experiments were repeated four times. Three specimens of wound tissue of mice in wild-type group on PID 7 were obtained to detect the relationship between E2F1 and PPAR-γ by co-immunoprecipitation and Western blotting, and this experiment was repeated two times. Data were processed with unpaired t test. Results: The size of PCR products of E2F1 gene knockout homozygotes C57BL/6 mice and wild-type C57BL/6 mice were 227 and 172 bp respectively, which were the same as those of the designed DNA fragments. On PID 2 and 7, the number of CD68 and CD206 double positive M2 macrophages in the wound tissue of mice in E2F1 gene knockout group was more than that of wild-type group, and the percentages of CD206 positive cells in the wound tissue of mice in E2F1 gene knockout group were (0.234±0.032)% and (0.584±0.023)% respectively, which were significantly higher than (0.129±0.017)% and (0.282±0.071)% of wild-type group (t=3.29, 3.54, P<0.05). On PID 2 and 7, the protein expression of CD206 in the wound tissue of mice in E2F1 gene knockout group were 1.00±0.23 and 1.63±0.26 respectively, which were significantly higher than 0.43±0.06 and 0.97±0.08 of wild-type group (t=2.41, 2.45, P<0.05). On PID 2 and 7, the mRNA expressions of arginase 1 in the wound tissue of mice in E2F1 gene knockout group were 0.482±0.105 and 0.195±0.031 respectively, which were significantly higher than 0.163±0.026 and 0.108±0.017 of wild-type group (t=3.04, 2.86, P<0.05). On PID 7, the protein and mRNA expressions of PPAR-γ in the wound tissue of mice in E2F1 gene knockout group were 0.61±0.12 and 0.51±0.13 respectively, which were significantly higher than 0.20±0.04 and 0.20±0.04 of wild-type group (t=3.36, 2.86, P<0.05). On PID 7, detection of the wound tissue of mice in wild-type group showed that PPAR-γ had unidirectional effect on E2F1. Conclusions: E2F1 transcription factor affects the polarization of M2 macrophages by inhibiting the expression of PPAR-γ, thereby inhibiting the healing process of full-thickness skin defect wounds in mice.

Control of pore structure in a porous gold nanoparticle for effective cancer cell damage

For tumor treatment, compared with gold nanoparticles (NPs) of other geometries, a porous gold NP (PGNP) has the advantages of stronger localized surface plasmon resonance (LSPR) due to the pore nanostructures and a larger surface area to link with more drug or photosensitizer (PS) molecules for more effective delivery into cancer cells. Different from the chemical synthesis methods, in this paper we demonstrate the fabrication procedures of PGNP based on shaped Au/Ag deposition on a Si substrate and elucidate the advantageous features. PGNPs fabricated under different conditions, including different deposited Au/Ag content ratios and different alloying annealing temperatures, are compared for optimizing the fabrication condition in terms of LSPR wavelength, PS linkage capability, and cancer cell damage efficiency. It is found that within the feasible fabrication parameter ranges, the Au/Ag content ratio of 3:7 and alloying annealing temperature at 600 °C are the optimized conditions. In comparing with widely used gold NPs of other geometries, PGNP fabricated under the optimized conditions can be used for achieving a significantly higher linked PS molecule number per unit gold weight.

Symptom Based Clustering of Women in the LURN Observational Cohort Study

PURPOSE

Women with lower urinary tract symptoms are often diagnosed based on a predefined symptom complex or a predominant symptom. There are many limitations to this paradigm as often patients present with multiple urinary symptoms which do not perfectly fit the preestablished diagnoses. We used cluster analysis to identify novel, symptom based subtypes of women with lower urinary tract symptoms.

MATERIALS AND METHODS

We analyzed baseline urinary symptom questionnaire data obtained from 545 care seeking female participants enrolled in the LURN (Symptoms of Lower Urinary Tract Dysfunction Research Network) Observational Cohort Study. Symptoms were measured with the LUTS (lower urinary tract symptoms) Tool and the AUA SI (American Urological Association Symptom Index), and analyzed using a probability based consensus clustering algorithm.

RESULTS

Four clusters were identified. The 138 women in cluster F1 did not report incontinence but experienced post-void dribbling, frequency and voiding symptoms. The 80 women in cluster F2 reported urgency incontinence as well as urgency and frequency but minimal voiding symptoms or stress incontinence. Cluster F3 included 244 women who reported all types of incontinence, urgency, frequency and mild voiding symptoms. The 83 women in cluster F4 reported all lower urinary tract symptoms at uniformly high levels. All but 2 of 44 LUTS Tool and 8 AUA SI questions significantly differed between at least 2 clusters (p <0.05). All clusters contained at least 1 member from each conventional group, including continence, and stress, urgency, mixed and other incontinence.

CONCLUSIONS

Women seeking care for lower urinary tract symptoms cluster into 4 distinct symptom groups which differ from conventional clinical diagnostic groups. Further validation is needed to determine whether management improves using this new classification.

Polarity Control in Growing Highly Ga-Doped ZnO Nanowires with the Vapor-Liquid-Solid Process

Surface behavior modification by forming surface-transparent conductive nanowires (NWs) is an important technique for many applications, particularly when the polarities of the NWs can be controlled. The polarities of Ga-doped ZnO (GaZnO) NWs grown on templates of different polarities under different growth conditions are studied for exploring a polarity control growth technique. The NWs are formed on Ga- and N-face GaN through the vapor-liquid-solid (VLS) process using Ag nanoparticles as growth catalyst. The NWs grown on templates of different polarities under the Zn- (O-) rich conditions are always Zn (O) polar. During the early stage of NW growth, because the lattice sizes among different nucleation islands formed at the triple-phase line are quite different, high-density planar defects are produced when lateral growths from multiple nucleation islands form a GaZnO double bilayer. In this situation, frequent domain inversions occur, and GaZnO polarity is unstable. Under the Zn- (O-) rich conditions, because the lateral growth rate of GaZnO in the Zn- (O-) polar structure is higher due to more available dangling bonds, the growth of the Zn- (O-) polar structure dominates NW formation such that the NW eventually becomes Zn (O) polar irrespective of the polarity of the growth template. Therefore, the polarity of a doped-ZnO NW can be controlled simply by the relative supply rates of Zn and O during VLS growth.

Further emission efficiency improvement of a commercial-quality light-emitting diode through surface plasmon coupling

It is usually believed that surface plasmon (SP) coupling is practically useful only for improving the performance of a light-emitting diode (LED) with a low intrinsic internal quantum efficiency (IQE). In this Letter, we demonstrate that the performance of a commercial-quality blue LED with a high IQE (>80%) can still be significantly improved through SP coupling based on a surface Ag nanoparticle (NP) structure. The performance improvement of such an LED is achieved by increasing the Mg doping concentration in its p-AlGaN electron blocking layer to enhance the hole injection efficiency such that the p-GaN layer thickness can be significantly reduced without sacrificing its electrical property. In this situation, the distance between surface Ag NPs and quantum wells is decreased and hence SP coupling strength is increased. By reducing the distance between the surface Ag NPs and the top quantum well to 66 nm, the IQE can be increased to almost 90% (an ∼11% enhancement) and the electroluminescence intensity can be enhanced by ∼24%.

Ancillary benefits of bladder chemodenervation for SCI neurogenic bladder

Study design

Case series.

Objective

Bladder chemodenervation is effective in treating neurogenic detrusor overactivity (NDO) in patients with neurogenic bladder due to spinal cord injury. Anecdotal reports also describe the improvement of non-bladder symptoms, specifically those related to autonomic dysreflexia (AD) and muscle spasticity. We conducted a study to further investigate this phenomenon.

Setting

USA, Urban Tertiary Care Center.

Methods

Twenty-one persons with SCI completed the study between March and December 2015. Mean age was 45 years (range 21-69). All were scheduled to undergo bladder chemodenervation with onabotulinumtoxinA 200 units to treat bothersome NDO refractory to oral medications. Each completed a questionnaire detailing symptoms unrelated to NDO immediately prior to the procedure, and again between 6 and 12 weeks after.

Results

All patients reported improvement in NDO symptoms following chemodenervation. Ten patients with prior symptoms of AD reported improvement in AD symptoms after injection. Seventeen patients reported skeletal muscle spasticity in the 3-month period before chemodenervation. In the follow up period, only 14 patients reported having muscle spasticity. In aggregate, 12 of 21 patients reported improvement of non-bladder symptomatology following chemodenervation.

Conclusions

Chemodenervation of the bladder in patients with SCI can provide ancillary benefits in addition to mitigation of lower urinary symptoms. The mechanism may be related to dampening the bladder's ability to initiate noxious reflex responses.

Efficiency enhancement of light color conversion through surface plasmon coupling

The efficiency enhancement of light color conversion from blue quantum well (QW) emission into red quantum dot (QD) emission through surface plasmon (SP) coupling by coating CdSe/ZnS QDs on the top of an InGaN/GaN QW light-emitting diode (LED) is demonstrated. Ag nanoparticles (NPs) are fabricated within a transparent conductive Ga-doped ZnO interlayer to induce localized surface plasmon (LSP) resonance for simultaneously coupling with the QWs and QDs. Such a coupling process generates three enhancement effects, including QW emission, QD absorption at the QW emission wavelength, and QD emission, leading to an overall enhancement effect of QD emission intensity. An Ag NP geometry for inducing an LSP resonance peak around the middle between the QW and QD emission wavelengths results in the optimized condition for maximizing QD emission enhancement. Internal quantum efficiency and photoluminescence (PL) decay time measurements are performed to show consistent results with LED performance characterizations, even though the QD absorption of PL excitation laser may mix with the SP-induced QD absorption enhancement effect in PL measurement.

Prevalence and Characteristics of Urinary Incontinence in a Treatment Seeking Male Prospective Cohort: Results from the LURN Study

PURPOSE

Male urinary incontinence is thought to be infrequent. We sought to describe the prevalence of urinary incontinence in a male treatment seeking cohort enrolled in the LURN (Symptoms of Lower Urinary Tract Dysfunction Research Network).

MATERIALS AND METHODS

Study inclusion and exclusion criteria, including men with prostate cancer or neurogenic bladder, were previously reported. LURN participants prospectively completed questionnaires regarding lower urinary tract symptoms and other clinical variables. Men were grouped based on incontinence type, including 1) no urinary incontinence, 2) post-void dribbling only and 3) urinary incontinence. Comparisons were made using ANOVA and multivariable regression.

RESULTS

Of the 477 men 24% reported no urinary incontinence, 44% reported post-void dribbling only and 32% reported urinary incontinence. African American men and those with sleep apnea were more likely to be in the urinary incontinence group than in the no urinary incontinence group (OR 3.2, p = 0.02 and OR 2.73, p = 0.003, respectively). Urinary incontinence was associated with significantly higher bother compared to men without leakage (p <0.001). Compared to men without urinary incontinence and men with only post-void dribbling those with urinary incontinence were significantly more likely to report higher scores (more severe symptoms) on the PROMIS (Patient-Reported Outcomes Measurement Information System) questionnaires regarding bowel issues, depression and anxiety than men without urinary incontinence (p <0.01).

CONCLUSIONS

Urinary incontinence is common among treatment seeking men. This is concerning because the guideline recommended questionnaires to assess male lower urinary tract symptoms do not query for urinary incontinence. Thus, clinicians may be missing an opportunity to intervene and improve patient care. This provides a substantial rationale for a new or updated symptom questionnaire which provides a more comprehensive symptom assessment.

Exocytosis of gold nanoparticle and photosensitizer from cancer cells and their effects on photodynamic and photothermal processes

We first illustrate the faster decrease of the photothermal (PT) effect with the delay time of laser treatment, in which the illumination of a 1064 nm laser effectively excites the localized surface plasmon (LSP) resonance of cell-up-taken gold nanoring (NRI) linked with a photosensitizer (PS), when compared with the photodynamic (PD) effect produced by the illumination of a 660 nm laser for effective PS excitation. The measurement results of the metal contents of Au NRI and PS based on inductively coupled plasma mass spectroscopy and the PS fluorescence intensity based on flow cytometry show that the linkage of NRI and PS is rapidly broken for releasing PS through the effect of glutathione in lysosome after cell uptake. Meanwhile, NRI escapes from a cell with a high rate such that the PT effect decays fast while the released PS can stay inside a cell longer for producing a prolonged PD effect. The effective delivery of PS through the linkage with Au NRI for cell uptake and the advantageous effect of LSP resonance at a PS absorption wavelength on the PD process are also demonstrated.

Physical Examination for Men and Women With Urologic Chronic Pelvic Pain Syndrome: A MAPP (Multidisciplinary Approach to the Study of Chronic Pelvic Pain) Network Study

OBJECTIVE

To examine the feasibility of implementing a standardized, clinically relevant genitourinary examination for both men and women, and to identify physical examination findings characteristic of urologic chronic pelvic pain syndrome (UCPPS).

MATERIALS AND METHODS

This study analyzed 2 samples: men and women with UCPPS who participated in the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) Research Network Epidemiology and Phenotyping (EP) Study, and age-matched controls who were either positive for chronic fatigue syndrome or healthy (pain-free). We compared physical examination findings in both positive and healthy controls with UCPPS cases: findings from both the EP examinations and from an extended genitourinary examination.

RESULTS

EP and extended examinations were performed on 143 participants: 62 UCPPS cases (30 women, 32 men), 42 positive controls (15 women, 27 men), and 39 healthy controls (22 women, 17 men). EP examinations showed that pelvic floor tenderness was more prevalent in cases (55.0%) than in positive (14.6%) or healthy controls (10.5%). Extended examinations revealed specific areas of tenderness in the pelvic floor musculature. Cases were also more likely than healthy controls to report tenderness in multiple areas, including suprapubic, symphysis pubis, and posterior superior iliac spine, and on bimanual examination. No comparative findings were specific to biological sex, and no evidence of pudendal neuropathy was observed on extended examination of cases or controls.

CONCLUSION

The extended genitourinary examination is an easily administered addition to the assessment of men and women during evaluation for UCPPS. Physical findings may help to better categorize patients with UCPPS into clinically relevant subgroups for optimal treatment.

Coupling of a light-emitting diode with surface plasmon polariton or localized surface plasmon induced on surface silver gratings of different geometries

A metal grating on top of a light-emitting diode (LED) with a designed grating period for compensating the momentum mismatch can enhance the surface plasmon polariton (SPP) coupling effect with the quantum wells (QWs) to improve LED performance. Here, we demonstrate the experimental results showing that the induced localized surface plasmon (LSP) resonance on such a metal grating can dominate the QW coupling effect for improving LED performance, particularly when grating ridge height is large. The finding is illustrated by fabricating Ag gratings on single-QW, green-emitting LEDs of different p-type thicknesses with varied grating ridge height and width such that the distance between the grating ridge tip and the QW can be controlled. Reflection spectra of the Ag grating structures are measured and simulated to identify the SPP or LSP resonance behaviors at the QW emission wavelength. The measured results of LED performances show that in the LED samples under study, both SPP and LSP couplings can lead to significant enhancements of internal quantum efficiency and electroluminescence intensity. At the designated QW emission wavelength, with a grating period theoretically designed for momentum matching, the LSP coupling effect is stronger, when compared with SPP coupling.

Different surface plasmon coupling behaviors of a surface Al nanoparticle between TE and TM polarizations in a deep-UV light-emitting diode

The formulations and numerical algorithms of a three-level model for studying the Purcell effect produced by the scattering of an air/AlGaN interface and the surface plasmon (SP) coupling effect induced by a surface Al nanoparticle in a two-polarization emission system to simulate the transverse-electric- (TE-) and transverse-magnetic- (TM-) polarized emissions in an Al_xGa_1-xN/Al_yGa_1-yN (y > x) quantum well (QW) are built. In reasonably selected ranges of Al content for an AlGaN QW to emit deep-ultraviolet (UV) light, the enhancement (suppression) of TE- (TM-) polarized emission is mainly caused by the SP-coupling (interface-scattering) effect. Different from a two two-level model, in the three-level model the TE- and TM-polarized emissions compete for electron in the shared upper state, which is used for simulating the conduction band, such that either interface-scattering or SP-coupling effect becomes weaker. In a quite large range of emission wavelength, in which the intrinsic emission is dominated by TM polarization, with the interface-scattering and SP-coupling effects, the TE-polarized emission becomes dominant for enhancing the light extraction efficiency of a deep-UV light-emitting diode.