Radiobiological Insights of Staged Brachytherapy Using Eye Plaque for Large Uveal Melanoma

PURPOSE/OBJECTIVE(S)

I-125 radioactive seeds embedded in an eye plaque is used to deliver the radiation dose of 85Gy to the apex of the tumor. However, it is challenging to treat a lesion in height (>10 mm) because of a high dose (> 500 Gy) to sclera. A staged radiotherapy (SRT) has been implemented successfully in stereotactic radiosurgery when a single dose is risky for a bigger sized lesion. The hypothesis of this work is that the SRT works for eye plaque brachytherapy of uveal melanoma to break the single fraction into two. To apply the concept of SRT, the following questions need to be answered: What are the two fraction doses? What is the time interval between the two fractions? In this work, the two split fraction doses and time interval are calculated using the "incomplete-repair' model.

MATERIALS/METHODS

Equation (1) is the linear-quadratic (LQ) model. f(x) is the cell survival curve (SC). Equation (2) and (3) are radiobiological model developed dealing with the split doses by considering the incomplete repair. Ln(f(x)) = -αx - βx2 (1) Ln(fn(x, Ɵ)) = nLn(f(x))-nβx2hn(Ɵ) (2) hn(Ɵ) = (2/n)[ Ɵ/(1- Ɵ)][n-(1- Ɵn)/(1- Ɵ)] (3) Ɵ = exp(-µΔt) (4) x represents the fraction dose, Ɵx is the initial segment of the survival curve, Ɵ determines the rate at which repair proceeds. n is fraction number and µ represent repair constant which equals to ln2/T1/2. T1/2 is the half-life of I-125. For continuous dose vt delivered at dose rate v for time t, with repair constant µ, the LQ model is modified as Ln (f(vt, µ)) = -α(vt) -β(vt)2g(µt) (5) g(µt) = 2[µt-1+exp(-µt)]/(µt)2 (6) Assuming biological effective dose (BED) is the same for the single fraction and split two fractions, SC when n = 1 should be same as when n = 2. Therefore, the equation (7) is derived. Ɵ = [(α/β)x1 - 2(α/β)(x2)2 + (x1)2]/2(x2)2 - 1 (7) x1 is single fraction dose of 85Gy, x2 is the split dose to two fractions. α/β ratio of 10 Gy is used. By fitting the equation (7), the ranges of doses and time intervals were determined.

RESULTS

The fraction doses and time interval to get the same BED as single fraction of 85 Gy are determined from 45 Gy to 50 Gy with time interval of 22 days to 76 days for staged brachytherapy eye plaque (SBEP). Our result is matched the treatment protocol for SBEP reported, e.g., 1st fraction dose of 40Gy and 50 Gy of 2nd fraction with 73 days of time interval are used. The max. dose of scleral dose is 328 Gy compared to the single fraction scleral dose of 543Gy.

CONCLUSION

This work could provide guidelines in SBEP in dosage and time interval. The height of tumor matters the most in the SBEP since the taller the tumor, the higher dose to the sclera is. Reference.

Difference in Radiotherapeutic Plan of HyperArc-Based and CyberKnife-Based Stereotactic Radiotherapy (SRT) Techniques for Multiple Brain Metastases

PURPOSE/OBJECTIVE(S)

The purpose of this study is to compare the dosimetric quality and dose to surrounding normal tissue of HyperArc-based stereotactic radiotherapy (SRT) technique with a frameless robotic radiosurgery system for patients with multiple brain metastases.

MATERIALS/METHODS

Nineteen patients with multiple brain metastases (2-5 lesions) treated in our center were enrolled. The prescribed dose was 2100 cGy to 3250 cGy in three to five fractions. In order to determine the dosimetric quality, we compared the conformity index (CI), Gradient radius (GR), homogeneity index (HI), dose distribution in planning target volume, and dose to several organs at risk (OARs). All of the data were compared using pair-T test.

RESULTS

Both planning systems have prescribed dose coverage to GTV and PTV with no significant difference (P = 0.243; P = 0.312). The conformity index (CI), and homogeneity index (HI) were 1.27 ±0.022, and 1.08 ±0.006, respectively, for HyperArc plan and 1.76 ±0.065 and 1.22 ±0.009, respectively, for the CK plan (both, P< 0.001). The Gradient radius (GR) was 0.732 ±0.056 cm for HyperArc plan and 0.847 ±0.762 cm for CK plan (P = 0.002). These indicated that HyperArc plan had better CI, HI, and GR when compared to CK plan. Maximum dose to brainstem for HyperArc and CK plans were 485.1 ±128.65 and 723.6 ±126.93 cGy, respectively (P < 0.001). Moreover, HyperArc plan had less mean dose to optic chiasm, bilateral eyes, bilateral lens, and bilateral optic nerves (all, P < 0.05). Brain V5, V12, V24 were all much smaller in HyperArc plan (all, P < 0.05), indicating that HyperArc plan delivered less dose to normal brain tissue.

CONCLUSION

For patients with two to five brain metastases, HyperArc-based SRT provide excellent dosimetric quality and less dose to normal tissue.

Development of the Chronic Pain Cognition Scale: A Culture-Sensitive Pain Measurement in Chinese

Purpose

People with pain problems are highly vulnerable to cultural disparities, and it is imperative to reduce these inequalities. This cross-sectional study aimed to develop a culturally sensitive Chronic Pain Cognition Scale (CPCS) for Chinese-/Chinese dialect-speaking populations and investigate its psychometric properties.

Patients and Methods

Adult patients with chronic low back pain or chronic neck pain who visited pain clinics at a medical center in northern Taiwan were enrolled. Participants completed the demographic, intensity of pain, and two other related sensations, "Sng ()" and "Ma ()", often reported in Chinese-speaking populations, CPCS, Chronic Pain Acceptance Questionnaire-8, and Pain Self-Efficacy Questionnaire.

Results

200 patients were included. Patients' mean age was 64.84 ± 14.33, 126 (63.0%) were female, and 83 (41.5%) had 13+ years of education. The average duration of pain was 77.25 ± 97.46 months, the intensity of pain was 6.04 ± 2.50, Ma was 3.43 ± 3.24, and Sng was 4.54 ± 3.14. The CPCS comprised four factors: pain impact (how pain impact one's life), losing face (how one being disrespected due to pain), helplessness, and avoidance, with good structural validity and adequate reliability (Cronbach α, 0.60-0.81) and satisfactory criterion-related validity. Moreover, losing face, an essential concept in Chinese relationalism, was significantly related to pain, Sng, and Ma (r = 0.19, 0.15 and 0.16), but not to pain acceptance or self-efficacy, indicating a culturally specific element in pain measurement.

Conclusion

The CPCS has good psychometric properties and is suitable for evaluating chronic pain in the clinical setting, and might be generalizable to other Chinese-/Chinese dialect-speaking populations.

Synthesis of Nano-Structured Ge as Transmissive or Reflective Saturable Absorber for Mode-Locked Fiber Laser

Amorphous-Ge (α-Ge) or free-standing nanoparticles (NPs) synthesized via hydrogen-free plasma-enhanced chemical vapor deposition (PECVD) were applied as transmissive or reflective saturable absorbers, respectively, for starting up passively mode-locked erbium-doped fiber lasers (EDFLs). Under a threshold pumping power of 41 mW for mode-locking the EDFL, the transmissive α-Ge film could serve as a saturable absorber with a modulation depth of 52-58%, self-starting EDFL pulsation with a pulsewidth of approximately 700 fs. Under a high power of 155 mW, the pulsewidth of the EDFL mode-locked by the 15 s-grown α-Ge was suppressed to 290 fs, with a corresponding spectral linewidth of 8.95 nm due to the soliton compression induced by intra-cavity self-phase modulation. The Ge-NP-on-Au (Ge-NP/Au) films could also serve as a reflective-type saturable absorber to passively mode-lock the EDFL with a broadened pulsewidth of 3.7-3.9 ps under a high-gain operation with 250 mW pumping power. The reflection-type Ge-NP/Au film was an imperfect mode-locker, owing to their strong surface-scattered deflection in the near-infrared wavelength region. From the abovementioned results, both ultra-thin α-Ge film and free-standing Ge NP exhibit potential as transmissive and reflective saturable absorbers, respectively, for ultrafast fiber lasers.

Surface plasmon coupling effects on the photon color conversion behaviors of colloidal quantum dots in a GaN nanoscale hole with a nearby quantum-well structure

To improve color conversion performance for color display application, we study the near-field-induced nanoscale-cavity effects on the emission efficiency and Förster resonance energy transfer (FRET) under the condition of surface plasmon (SP) coupling by inserting colloidal quantum dots (QDs) and synthesized Ag nanoparticles (NPs) into surface nano-holes fabricated on a GaN template and an InGaN/GaN quantum-well (QW) template. In the QW template, the inserted Ag NPs are close to either QWs or QDs for producing three-body SP coupling to enhance color conversion. Time-resolved and continuous-wave photoluminescence (PL) behaviors of the QW- and QD-emitting lights are investigated. The comparison between the nano-hole samples and the reference samples of surface QD/Ag NP shows that the nanoscale-cavity effect of the nano-hole leads to the enhancements of QD emission, FRET between QDs, and FRET from QW into QD. The SP coupling induced by the inserted Ag NPs can enhance the QD emission and FRET from QW into QD. Its result is further enhanced through the nanoscale-cavity effect. The relative continuous-wave PL intensities among different color components also show the similar behaviors. By introducing SP coupling to a color conversion device with the FRET process in a nanoscale cavity structure, we can significantly improve the color conversion efficiency. Simulation results confirm the basic observations in experiment.

Quality of life outcomes after surgical intervention in patients with multiple rib fractures: A prospective cohort study

BACKGROUND

Optimized conservative treatment of rib fractures has long been practiced, but surgical fixation has not been promising until recently. We aimed to examine and analyze immediate postoperative outcomes and 6-month quality of life after injury in patients with moderately severe traumatic rib fractures.

METHODS

We conducted a prospective cohort study between July 2017 and June 2019 at the National Taiwan University Hospital. Seventy-two patients with moderately severe thoracic trauma were enrolled; 38 received conservative treatment and 34 underwent surgical fixation. Quality of life was measured using the 36-item Short Form Survey at; the first 3 days of hospitalization; before discharge; and at 1-, 2-, and 6-month follow-ups (visits 1-5). Baseline characteristics and clinical outcomes were recorded, and linear regression analysis was conducted using the generalized estimating equation.

RESULTS

Among patients with moderately severe thoracic injury (chest Abbreviated Injury Scale score≥ 2), the operative group had more severe injuries and longer intensive care unit and in-hospital stays. However, they had a comparable quality of life 6 months after injury and higher physical component scores in the early postoperative period. Linear regression analysis obtained an equation with several factors positively affecting prediction of the mean physical component score, such as body mass index ≤25, age ≤36 years, fewer ribs requiring fixation, and diabetes mellitus. Mental component score did not show an upward trend, but the Work Quality Index largely determined the predicted mean value of the mental component score.

CONCLUSION

Surgical rib fixations hasten recovery in patients with severe thoracic injury (chest Abbreviated Injury Scale ≥3) to achieve 6-month quality of life comparable to patients injured less severely (chest Abbreviated Injury Scale ≥2). The ability to resume previous work positively influenced the mental component score; thus, surgical intervention should also aim to help patients regain their social function.

Long-term work quality of patients with mild traumatic brain injury: The associations with postconcussion symptoms

Return to work (RTW) has always been a determinant functional outcome in patients with mild traumatic brain injury (MTBI). However, the quality of long-term RTW was still unclear. This study thus aims to examine long-term work quality and to reveal its associating factors. A total of 110 patients with MTBI was prospectively recruited. Post-concussion symptoms (PCS) and RTW were evaluated by the Checklist of Post-Concussion Symptoms (CPCS) and Work Quality Index (WQI) respectively at one-week and long-term evaluation (M = 2.90 years, SD = 1.29) post-injury. Only 16% of patients can successfully RTW at one-week post-injury, while 69% of patients have retained their jobs at long-term evaluations. Importantly, 12% of patients had to work under the adverse impacts of PCS at one-week after MTBI, and long-term WQI was significantly associated with PCS at one-week post-injury. Almost 1/3 of patients still had unfavorable long-term work quality even though they could return to work. Thus, a careful evaluation of the early PCS endorsement and work quality for patients with MTBI is merited.

Photon color conversion enhancement of colloidal quantum dots inserted into a subsurface laterally-extended GaN nano-porous structure in an InGaN/GaN quantum-well template

To improve the color conversion performance, we study the nanoscale-cavity effects on the emission efficiency of a colloidal quantum dot (QD) and the Förster resonance energy transfer (FRET) from quantum well (QW) into QD in a GaN porous structure (PS). For this study, we insert green-emitting QD (GQD) and red-emitting QD (RQD) into the fabricated PSs in a GaN template and a blue-emitting QW template, and investigate the behaviors of the photoluminescence (PL) decay times and the intensity ratios of blue, green, and red lights. In the PS samples fabricated on the GaN template, we observe the efficiency enhancements of QD emission and the FRET from GQD into RQD, when compared with the samples of surface QDs, which is attributed to the nanoscale-cavity effect. In the PS samples fabricated on the QW template, the FRET from QW into QD is also enhanced. The enhanced FRET and QD emission efficiencies in a PS result in an improved color conversion performance. Because of the anisotropic PS in the sample surface plane, the polarization dependencies of QD emission and FRET are observed.

Neuropsychological performances in patients with infiltrative non-GBM gliomas after postoperative adjuvant photon or proton radiotherapy: A prospective and preliminary investigation

Infiltrative non-GBM gliomas are common primary intracranial malignancies, and postoperative adjuvant radiotherapy is recommended for most adult patients diagnosed with this disease to enhance local control and prolong intracranial progression-free survival (PFS). However, RT-related neurocognitive function (NCF) consequences should not be ignored. Early neurocognitive decline principally includes episodic memory, associated significantly with functions of the hippocampus. This prospective study aims to investigate the impact of adjuvant brain irradiation on neurocognitive performances and relevant oncological outcomes.Twenty-five patients with intracranial infiltrative non-GBM gliomas were enrolled when postoperative adjuvant RT was recommended. All recruited patients should receive baseline brain magnetic resonance imaging, and neuropsychological assessments before and 4 months after the RT course. A battery of neuropsychological measures, mainly including executive functions, memory, psychomotor speed and visuoconstructive ability, was used to evaluate NCFs of interest.Analyzing the delta values between post-irradiation and baseline NCF scores, we observed a robust trend reflecting cognitive stabilization rather than deterioration in almost all NCF. Both verbal and visual memory functions exhibited significant differences in the corresponding scaled scores (Z = -2.722, p = .006, regarding verbal memory; Z = -2.246, p = .025, concerning non-verbal memory). Moreover, patients' neuropsychological performances associated with psychomotor speed and executive functions also disclosed a tendency toward stabilization/improvement.This prospective study demonstrated that patients with infiltrative non-GBM exhibited a marked tendency toward neurocognitive stabilization after receiving postoperative adjuvant RT. Clinical trial registration: Trial Registration with ClinicalTrials.gov identifier: NCT03534050.

Pre-Injury headache and post-traumatic headache in patients with mild traumatic brain injury: neuropsychological, psychiatric, and post-concussion symptom outcomes

PRIMARY OBJECTIVE

Headache, both before and after injury, has been associated with worse outcome following mild traumatic brain injury (MTBI). This study examined whether three MTBI patient groups - no headache (reported no pre-/post-injury headache), pre-injury headache (reported pre-injury headache, nearly all of whom also reported post-injury headache), and post-traumatic headache only (denied pre-injury headache and reported post-injury headache) - differed in acute-to-subacute outcomes.

RESEARCH DESIGN

Cross-sectional observational study.

METHODS AND PROCEDURES

Patients within 21 days of a MTBI (n = 291) completed neuropsychological tests and questionnaires evaluating depression, anxiety, and post-concussion symptoms.

MAIN OUTCOMES AND RESULTS

Neuropsychological test performances did not differ between headache groups. Participants with pre-injury headache and participants with post-traumatic headache only reported greater change in self-reported physical and cognitive symptoms than participants with no headache. Participants with pre-injury headache reported worse post-injury anxiety symptoms than participants with post-traumatic headache only.

CONCLUSIONS

The pre-injury headache and post-traumatic headache only groups did not meaningfully differ in outcome within 21 days of MTBI, but they had worse physical and cognitive symptoms than participants with no headache. Future research should assess whether differences in outcome emerge further from injury and whether specific headache subtypes are differentially associated with outcome.

Oncological Outcomes After Hippocampus-Sparing Whole-Brain Radiotherapy in Cancer Patients With Newly Diagnosed Brain Oligometastases: A Single-Arm Prospective Observational Cohort Study in Taiwan

Background

Promisingly, the technique of hippocampus sparing during WBRT (HS-WBRT) might preserve NCFs. In this research, we examined oncological outcomes, with emphasis on neurologic/non-neurologic causes of death, CNS progression, and leptomeningeal disease (LMD) recurrence in cancer patients who underwent HS-WBRT.

Methods

One hundred and fourteen cancer patients with newly diagnosed brain oligometastases underwent HS-WBRT were consecutively enrolled. The cumulative incidence of cancer-specific deaths (neurologic or non-neurologic), LMD recurrence, and the composite endpoint of CNS progression (CNS-CE) as the first event were computed with a competing-risks approach to characterize the oncological outcomes after HS-WBRT.

Results

Patients with intact brain metastases had a significantly increased likelihood of dying from non-neurologic causes of death associated with early manifestation of progressive systemic disease (hazard ratio for non-neurologic death, 1.78; 95% CI, 1.08–2.95; p = 0.025; competing-risks Fine–Gray regression), which reciprocally rendered them unlikely to encounter LMD recurrence or any pattern of CNS progression (HR for CNS-CE as the first event, 0.13; 95% CI, 0.02–0.97; p = 0.047; competing-risks Fine–Gray regression). By contrast, patients with resection cavities post-craniotomy had reciprocally increased likelihood of CNS progression which might be associated with neurologic death eventually.

Conclusions

Patterns of oncological endpoints including neurologic/non-neurologic death and cumulative incidence of CNS progression manifesting as LMD recurrence are clearly clarified and contrasted between patients with intact BMs and those with resection cavities, indicating they are clinically distinct subgroups.

Trial Registration

ClinicalTrials.gov, Identifier: NCT02504788, NCT03223675.

Enhancing deep-UV emission at 234 nm by introducing a truncated pyramid AlN/GaN nanostructure with fine-tuned multiple facets

The external quantum efficiency of a high-Al content (>0.6) AlGaN deep-ultraviolet (DUV) light-emitting diode is typically below 1% in the sub-250 nm wavelength range. One of the main reasons for this low efficiency is the fundamental properties of high-Al content AlGaN comprising the transverse-magnetic (TM)-dominant emission and low light extraction due to the total internal reflection (TIR). This work demonstrates a truncated pyramid nanostructure with fine-tuned multiple facets in an (AlN)₈/(GaN)₂ digital alloy to achieve highly efficient DUV emission at 234 nm. By applying nanoimprint lithography, dry and wet etching, a hexagonal truncated pyramid nanohole structure is fabricated featuring multiple crystal facets of (0001), (10-13), and (20-21) planes. These fine-tuned multiple facets act as reflecting mirrors that can effectively modulate the light propagation and extraction patterns to overcome the TIR via multiple reflections and enhanced scattering. Consequently, significant light extraction enhancements of 5.6 times and 1.1 times for TM and transverse-electric emissions are achieved in the truncated pyramid nanohole structure, respectively. The total luminous intensity of this unique nanostructure is greatly increased by 191% compared to that of a conventional planar structure. The truncated pyramid AlN/GaN nanostructure with fine-tuned multiple facets used in this work provides a promising approach for realizing highly efficient sub-250 nm DUV light-emitting devices.

[Role of inducible costimulatory molecules (ICOS) and related cytokines in immune regulation of Echinococcus granulosus infections in mice]

OBJECTIVE

To investigate the roles of inducible costimulatory molecules (ICOS) and related cytokines in the immune regulation of Echinococcus granulosus infections in mice.

METHODS

Eighty BALB/c mice (weight 18-22 g) were divided into the control and infection groups, of 40 animals in each group. E. granulosus infection was modeled in mice by intraperitoneal injection of 10 000 protoscoleces per mouse. Serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP) and peripheral interleukin-4 (IL-4) and IL-10 levels were measured 2, 8, 30, 60, 180 days post-infection. Mouse liver specimens were excised for hematoxylin-eosin (HE) staining and immunostaining, and ICOS expression was quantified in mouse liver specimens using quantitative real-time PCR (qPCR) assay.

RESULTS

There were no significant differences in serum ALT (F = 12.082, P < 0.05), AST (F = 6.347, P < 0.05) or ALP levels (F = 52.186, P < 0.05) in mice 2, 8, 30, 60 and 180 days post-infection with E. granulosus. The serum ALT levels were significantly higher in the infection group than in the control group 2 [(61.72 ± 9.89) vs. (50.65 ± 4.67)U/L, P < 0.05] and 30 days post-infection [(80.61 ± 23.71)vs.(67.75 ± 9.79)U/L, P < 0.05], and the serum ALT levels were significantly higher in the infection group than in the control group 2 [(181.06 ± 60.61) vs.(115.58 ± 17.66)U/L, P < 0.05] and 180 days post-infection [(137.84 ± 29.01) vs. (108.05 ± 10.33) U/L, P < 0.05], while greater serum ALP levels were measured in the infection group than in the control group 2 [(162.90 ± 21.04)vs.(64.54 ± 5.99)U/L, P < 0.05], 8[(176.36 ± 24.56) vs. (62.70 ± 9.21)U/L, P < 0.05] and 30 days post-infection [(138.86 ± 13.59) vs. (58.60 ± 5.28) U/L, P < 0.05]. A few inflammatory cells were seen in mouse liver in the infection group 30 days post-infection, and no apparent changes were found in the mouse hepatic structure 60 days post-infection. On day 180 post-infection, a large number of epithelium-like cells presented fibrotic growth in mouse liver in the cyst-infiltrating regions, with cuticula formation seen, and plenty of red cells were present in lesions and hepatocyte space. Positive ICOS expression was detected in mouse liver in the infection group, with ICOS-positive cells predominantly seen in the cytoplasm of the hepatocyte, and the ICOS expression increased over time. The relative ICOS mRNA expression was 2.732 ± 0.094 on day 180 post-infection, which was significantly greater than that on day 2 postinfection (0.746 ± 0.049). There were no significant differences in serum IL-4 or IL-10 levels at different time points after E. granulosus infections, while the serum IL-4 and IL-10 levels peaked in the infection group 180 days and 60 days post-infection, respectively. Higher serum IL-4 levels were measured in the infection group than in the control group 8 [(22.50 ± 3.24) vs. (5.82 ± 0.49) pg/mL, P < 0.05], 30 [(15.49 ± 4.73) vs. (5.10 ± 1.38) pg/mL, P < 0.05], 60 [(36.93 ± 6.14) vs. (4.13 ± 1.19) pg/mL, P < 0.05] and 180 days post-infection [(198.35 ± 0.70) vs. (4.19 ± 0.98) pg/mL, P < 0.05], and higher IL-10 levels were measured in the infection group than in the control group 2 [(4.84 ± 1.91) vs. (2.11 ± 1.03) pg/mL, P < 0.05], 8 [(44.72 ± 14.63) vs. (3.16 ± 0.60) pg/mL, P < 0.05], 30 [(25.47 ± 8.00) vs. (3.83 ± 1.87) pg/mL, P < 0.05], 60 [(187.16 ± 60.44) vs. (3.69 ± 1.05) pg/mL, P < 0.05] and 180 days post-infection [(85.40 ± 7.15) vs. (3.25 ± 0.93) pg/mL, P < 0.05].

CONCLUSIONS

High ICOS expression is present in the liver of mice with E. granulosus infections. The positive ICOS expression and immune activation levels increase with the time of E. granulosus infections, leading to aggravation of hepatocyte injury caused by inflammation.

Mesh size control in forming an Ag/AgO nano-network structure for transparent conducting application

The variation behaviors of the morphology, transmission, and sheet resistance of the surface Ag/AgO nano-network (NNW) structures fabricated under different illumination conditions and with different Ag deposition thicknesses and thermal annealing temperatures in forming initial Ag nanoparticles (NPs) are studied. Generally, an NNW structure with a smaller mesh size or a denser branch distribution has a lower transmission and a lower sheet resistance level. Under the fabrication condition of a broader illumination spectrum, a lower thermal annealing temperature, or a thicker Ag deposition, we can obtain an NNW structure of a smaller mesh size. The mesh size of an NNW structure is basically controlled by the seed density of Brownian tree (BT) at the beginning of light illumination. A BT seed can be formed through a stronger local localized surface plasmon resonance for accelerating Ag oxidation in a certain region. Once an Ag/AgO BT seed is formed, the surrounding Ag NPs are reorganized to form the branches of a BT. Multiple BTs are connected to form a large-area NNW structure, which can serve as a transparent conductor. Under the fabrication conditions of a broader illumination spectrum, 3 nm Ag deposition, and 100 °C thermal annealing, we can implement an NNW structure to achieve ∼1.15μm in mesh size, ∼90 Ω sq^-1in sheet resistance, and 93%-77% in transmittance within the wavelength range between 370 and 700 nm.

A-97 Headache before and after Mild Traumatic Brain Injury: Acute-to-Subacute Outcomes in Patients with no Headache, Pre-Existing Headache, and Post-Traumatic Headache

Objective

Patients who experience a mild traumatic brain injury (MTBI) may have a headache condition preceding injury, develop a post-traumatic headache after injury, or experience headache neither before nor after injury. This study examined whether MTBI patients with no headache, pre-existing headache, and post-traumatic headache differed in acute-to-subacute outcomes.

Method

Patients with MTBI were recruited from an outpatient neurosurgery clinic in Taipei, Taiwan after emergency department referral (N = 291; 40.2% men; M = 37.9 ± 13.9 years-old; Mdn = 7 days-since-injury, range = 0–21), completing neuropsychological tests of attention, memory, and verbal fluency and questionnaires evaluating depression, anxiety, and post-concussion symptoms. Participants with no headache (reported neither pre- or post-injury), pre-existing headache (reported pre-injury headache, of whom some reported worsened post-injury headache), and post-traumatic headache (denied pre-injury headache, reported post-injury headache) were compared using non-parametric ANCOVA, controlling for gender and days-since-injury.

Results

Neuropsychological test performances did not differ between headache groups. Participants with pre-injury headache and post-traumatic headache had greater change in self-reported physical (F = 25.52, p &lt; 0.011, η2 = 0.15) and cognitive symptoms (F = 3.74, p = 0.025, η2 = 0.03) than participants with no headache. Participants with pre-injury headache reported worse post-injury anxiety symptoms than participants with post-traumatic headache (F = 12.02, p &lt; 0.011, η2 = 0.08).

Conclusion(s)

Participants with pre-injury and post-traumatic headache did not differ in outcome within 21 days of injury but had worse self-reported physical and cognitive symptoms than participants with no headache. Most participants with pre-injury headache experienced worsened headache following MTBI (53.7%). Future research is needed to assess whether more specific headache subtypes are differentially associated with MTBI outcome.

Surface plasmon coupling effects on the förster resonance energy transfer from quantum dot into rhodamine 6G

Rhodamine 6G (R6G) molecules linked CdZnSeS/ZnS green-emitting quantum dots (QDs) are self-assembled onto Ag nanoparticles (NPs) for studying the surface plasmon (SP) coupling effect on the Förster resonance energy transfer (FRET) process from QD into R6G. SP coupling can enhance the emission efficiency of QD such that FRET has to compete with QD emission for transferring energy into R6G. It is found that FRET efficiency is reduced under the SP coupling condition. Although R6G emission efficiency can also be enhanced through SP coupling when it is directly linked onto Ag NP, the enhancement decreases when R6G is linked onto QD and then the QD-R6G complex is self-assembled onto Ag NP. In particular, R6G emission efficiency can be reduced through SP coupling when the number of R6G molecules linked onto a QD is high. A rate-equation model is built for resembling the measured photoluminescence decay profiles and providing us with more detailed explanations for the observed FRET and SP coupling behaviors.

Hippocampal avoidance whole-brain radiotherapy without memantine in preserving neurocognitive function for brain metastases: a phase II blinded randomized trial

BACKGROUND

Hippocampal avoidance whole-brain radiotherapy (HA-WBRT) shows potential for neurocognitive preservation. This study aimed to evaluate whether HA-WBRT or conformal WBRT (C-WBRT) is better for preserving neurocognitive function.

METHODS

This single-blinded randomized phase II trial enrolled patients with brain metastases and randomly assigned them to receive HA-WBRT or C-WBRT. Primary endpoint is decline of the Hopkins Verbal Learning Test-Revised (HVLT-R) delayed recall at 4 months after treatment. Neurocognitive function tests were analyzed with a mixed effect model. Brain progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method.

RESULTS

From March 2015 to December 2018, seventy patients were randomized to yield a total cohort of 65 evaluable patients (33 in the HA-WBRT arm and 32 in the C-WBRT arm) with a median follow-up of 12.4 months. No differences in baseline neurocognitive function existed between the 2 arms. The mean change of HVLT-R delayed recall at 4 months was -8.8% in the HA-WBRT arm and +3.8% in the C-WBRT arm (P = 0.31). At 6 months, patients receiving HA-WBRT showed favorable perpetuation of HVLT-R total recall (mean difference = 2.60, P = 0.079) and significantly better preservation of the HVLT-R recognition-discrimination index (mean difference = 1.78, P = 0.019) and memory score (mean difference = 4.38, P = 0.020) compared with patients undergoing C-WBRT. There were no differences in Trail Making Test Part A or Part B or the Controlled Oral Word Association test between the 2 arms at any time point. There were no differences in brain PFS or OS between arms as well.

CONCLUSION

Patients receiving HA-WBRT without memantine showed better preservation in memory at 6-month follow-up, but not in verbal fluency or executive function.

Combined effects of surface plasmon coupling and Förster resonance energy transfer on the light color conversion behaviors of colloidal quantum dots on an InGaN/GaN quantum-well nanodisk structure

By forming nanodisk (ND) structures on a blue-emitting InGaN/GaN quantum-well (QW) template, the QWs become close to the red-emitting quantum dots (QDs) and Ag nanoparticles (NPs) attached onto the sidewalls of the NDs such that Förster resonance energy transfer (FRET) and surface plasmon (SP) coupling can occur to enhance the efficiency of blue-to-red color conversion. With a larger ND height, more QWs are exposed to open air on the sidewall for more QD/Ag NP attachment through QD self-assembly and Ag NP drop casting such that the FRET and SP coupling effects, and hence the color conversion efficiency can be enhanced. A stronger FRET process leads to a longer QD photoluminescence (PL) decay time and a shorter QW PL decay time. It is shown that SP coupling can enhance the FRET efficiency.

Baseline preseason ImPACT® testing in Mandarin with adolescent student-athletes in the United States

Researchers have examined differences on ImPACT^® in baseline symptom reporting and neurocognitive performances based on the language of administration and racial/ethnic identity. This is the first study to examine differences between student-athletes tested in Mandarin versus English on ImPACT^® during preseason baseline assessments conducted in high schools in the United States. Participants included 252 adolescent student-athletes who completed ImPACT^® testing in the state of Maine in Mandarin and 252 participants who completed testing in English, matched on age, gender, and health and academic history. Participants were compared on neurocognitive composite scores and symptom ratings. Boys tested in Mandarin, but not girls, had modestly better neurocognitive performance on one of four composite scores (i.e., Visual Motor Speed, p < .001, d = .45). Although language groups did not differ in total symptom severity, boys tested in Mandarin endorsed multiple physical symptoms at higher rates than boys tested in English. These results suggest that the current ImPACT^® neurocognitive normative data are reasonably appropriate for use with adolescents evaluated in Mandarin. There were some differences in the reporting of physical symptoms, with greater rates of symptom endorsement by boys tested in Mandarin than boys tested in English; but overall symptom severity ratings were comparable between the language groups.

Förster resonance energy transfer in surface plasmon coupled color conversion processes of colloidal quantum dots

Förster resonance energy transfer (FRET) from a green-emitting quantum dot (GQD) into a red-emitting quantum dot (RQD) is an important mechanism in a multiple-color conversion process, particularly under the surface plasmon (SP) coupling condition for enhancing color conversion efficiency. Here, the dependencies of FRET efficiency on the relative concentrations of GQD and RQD in their mixtures and their surface molecule coatings for controlling surface charges are studied. Also, the SP coupling effects induced by two kinds of Ag nanoparticles on the emission behaviors of GQD and RQD are demonstrated, particularly when FRET is involved in the coupling process. FRET efficiency is reduced under the SP coupling condition. SP coupling can enhance the color conversion efficiency of either GQD or RQD. The combination of SP coupling and FRET can be used for controlling the relative converted light intensities in a multiple-color conversion process.

Long-Term Presentation of Postconcussion Symptoms and Associated Factors: Analysis of Latent Class Modeling

OBJECTIVE

Postconcussion symptoms (PCS) are commonly reported by patients with mild traumatic brain injury (MTBI). Although PCS significantly recovered by 3-month postinjury, a number of patients still experienced persistent PCS for >1 year. As few researchers investigated long-term PCS endorsement, the present study thus aims to show the latent structure of long-term PCS and further uncover its associating factors.

METHODS

In total, 110 patients with MTBI and 32 healthy participants were prospectively enrolled. PCS was evaluated at 2 weeks and long-term evaluations (mean = 2.90 years) after MTBI. In addition, cognitive functions, which include memory, executive function, and information processing, and emotional disturbances, which include depression, anxiety, and irritability, were also examined at 2-week postinjury.

RESULTS

Patients reported significantly more PCS at 2-week postinjury than healthy participants did, but PCS significantly improved at long-term evaluations when comparing with PCS at acute stage after MTBI. Both of PCS at 2 weeks and long-term evaluations can be further subdivided into subgroups based on the severity of PCS, in which specific PCS (e.g., fatigue, loss of energy, insomnia, slowness of information processing, irritability, and blurred vision) can be well differentiated among subgroups at long-term evaluations.

CONCLUSIONS

This study directly showed the characteristics of long-term PCS and associating factors. It further evidenced that specific physical, cognitive, and emotional symptoms might be determinant to identify the subgroups of patients with long-term PCS endorsement.

Complicated versus uncomplicated mild traumatic brain injuries: A comparison of psychological, cognitive, and post-concussion symptom outcomes

INTRODUCTION

A complicated mild traumatic brain injury (MTBI) is defined as mild by all clinical severity indicators but is complicated due to a traumatic intracranial abnormality visible on neuroimaging. Researchers have reported mixed findings regarding whether neuropsychological and functional outcomes following complicated MTBI are worse than, or similar to, outcomes following uncomplicated MTBI. This study examined patients referred from a Taiwanese emergency department to a neurosurgical outpatient clinic. Participants with complicated MTBI, uncomplicated MTBI, and those who did not undergo head computed tomography (CT) were compared on psychological, neuropsychological, and post-concussion symptom outcomes within 21 days of injury.

METHOD

Participants with complicated MTBI (n = 42), uncomplicated MTBI (n = 77), and no head CT (n = 172) completed the Paced Auditory Serial Attention Test, Taiwanese Word Sequence Learning Test, a semantic Verbal Fluency Test, the Checklist of Post-Concussion Symptoms, and the Beck Depression and Anxiety Inventories.

RESULTS

No significant differences were observed between groups on any measure. For individual post-concussion symptoms, dizziness, anxiety, and attention difficulty were endorsed more often after uncomplicated MTBIs, but these group differences were not significant after controlling for multiple comparisons.

CONCLUSIONS

Participants with complicated MTBIs did not have worse acute or subacute outcomes than participants with uncomplicated MTBIs or no head CT. These results are consistent with many studies finding comparable outcomes between those with complicated and uncomplicated MTBIs. This study is limited by small sample size and minimal information on intracranial abnormalities, broadly categorizing groups based on positive or negative neuroimaging as opposed to specific lesion types and locations.

Postoperative change of neuropsychological function after indirect revascularization in childhood moyamoya disease: a correlation with cerebral perfusion study

PURPOSE

The relationships between postoperative functional improvement in various cognitive domains and regional hemodynamic change have not been sufficiently studied in childhood moyamoya disease (MMD). The present study aimed to examine the cognitive benefit of indirect revascularization, the underlying biological mechanism, and factors affecting surgical outcome in childhood MMD.

METHODS

Twenty-three patients with MMD aged under 20 years received neuropsychological examinations before and after indirect revascularization surgery, evaluating intellectual function, verbal and visual memory, and executive function. Among them, 13 patients had magnetic resonance perfusion (MRP) studies, in which regional cerebral perfusion was rated.

RESULTS

Postoperative improvement was observed in verbal memory performances (p = 0.02-0.03) and in cerebral perfusion at all 26 cerebral hemispheres (p = 0.003-0.005), especially in the middle cerebral artery (MCA) territories (p = 0.001-0.003). Hemodynamic improvement in the left MCA territories was significantly correlated with improvement of both verbal new learning (p = 0.01) and intellectual function (p = 0.004). Postoperative cognitive improvement of immediate recall and verbal intellectual function was associated with female sex (r = - 0.42) and symptom duration (p = - 0.03), respectively. Hemodynamic improvement in the MCA territories was related to longer follow-up intervals (p = 0.02).

CONCLUSION

The findings revealed that the selective postoperative cognitive improvement was associated with increased regional perfusion in the MCA territories, and indicate the importance of early intervention and the potential of indirect revascularization regarding long-term outcome.

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.

Maintenance of multi-domain neurocognitive functions in patients with newly-diagnosed primary CNS lymphoma after primary cranial radiotherapy combined with methotrexate-based chemotherapy: A preliminary case-series study

Conventional treatment for treating primary central nervous system lymphoma (PCNSL) has consisted of either whole-brain radiotherapy (WBRT) or methotrexate (MTX)-based combined modality therapy. However, delayed cognitive sequelae have emerged as a significant debilitating complication in PCNSL patients. A prospective observational case-series study with prospective assessments of neurocognitive functions (NCFs), neuroimaging, and activities of daily living in newly-diagnosed PCNSL patients was undertaken. A battery of neuropsychological measures, used to evaluate NCFs, is composed of ten standardized NCF tests, representing four domains sensitive to disease and treatment effects (executive function, attention, verbal memory, psychomotor speed), and activities of daily living. A total of 15 patients with newly-diagnosed PCNSL were consecutively enrolled in this study. Comparing the NCF scores between the baseline (before WBRT) and post-treatment (after combined chemoradiation therapy) intervals (Mean = 122.33 days, SD = 34.49, range = 77-196), neurobehavioral outcomes consistently remained improving or stable in almost each domain of NCF. Specifically, the scores on Paced Auditory Serial Addition Test-Revised (PASAT-R) were significantly improved between the baseline and post-chemoradiation assessment. Under the multidisciplinary treatment guidelines for treating patients with newly-diagnosed PCNSL, multi-domain NCF become stabilized and even improved after the course of conformal WBRT combined with or without MTX-based chemotherapy.

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.

Perceived Change in Physical, Cognitive, and Emotional Symptoms after Mild Traumatic Brain Injury in Patients with Pre-Injury Anxiety or Depression

The objective of this study was to compare patients with acute-to-subacute mild traumatic brain injury (mTBI) on post-concussion symptom reporting based on whether they retrospectively recalled experiencing pre-injury anxiety or depression. Patients with mTBI (n = 297; 40.4% men; mean = 38.2 years old, standard deviation [SD] = 14.0, range = 17-65), referred from an emergency department in Taipei, Taiwan, were seen in a neurosurgical outpatient clinic on average 7.7 days since injury (SD = 5.7, range = 0 - 21 days), at which time they completed a checklist of post-concussion symptoms. Patients rated their current symptom severity and retrospectively rated their pre-injury symptom severity on 15 physical, cognitive, and emotional symptoms. Patients were grouped based on whether they did or did not have mild or greater pre-injury anxiety or depression based on this scale. Those with pre-injury anxiety or depression had greater pre-injury (all p's < 0.001, d range: 0.92-2.03) and post-injury (all p's < 0.001, d range: 0.65-1.00) symptom severity. However, when analyzing perceived change in symptoms (i.e., post-injury ratings minus pre-injury ratings), only perceived change in cognitive symptoms differed across groups (p = 0.018, d = 0.29), which became non-significant after controlling for gender. Greater post-concussion symptom severity in patients with pre-existing mental health problems may be mostly attributable to elevated symptoms before injury. These findings demonstrate the clinical value of retrospective pre-injury symptom assessment in mTBI management. Greater post-concussion symptom severity in patients with pre-injury mental health problems may represent a continuation of greater pre-injury symptom severity rather than a greater increase in symptom severity after mTBI.

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.

Heterogeneous influences of emotional disturbances on multi-domain quality of life after anterior cervical spine surgery: A prospective study

OBJECTIVE

Quality of life (QoL) has been identified as one of the most important outcome measurements following cervical spine surgery. The contributing factors to post-operative QoL remain limited. This study thus aimed to prospectively examine the QoL and related pre-operative emotional factors in patients who underwent anterior cervical spine surgery.

PATIENTS AND METHODS

A total of 124 patients who underwent anterior cervical spine surgery were recruited. All participants were prospectively evaluated for their QoL and 2 aspects of emotion, depression and anxiety, before and after surgery, respectively.

RESULTS

Pre-operatively, 13% of patients showed signs of depression and 31% of patients reported symptoms of anxiety. Post-operatively 14% of patients reported depression, but 41% reported symptoms of anxiety. A significant association between depression, anxiety and different domains of QoL were identified, and specific cut-off points of pre-operatively depressive and/or anxiety levels to predict unfavorable post-operative QoL were further established.

CONCLUSIONS

This prospective study demonstrated specific emotional factors, specifically depression and anxiety, influence patients' QoL following surgery. These results suggest clinicians should also monitor patients' emotional adjustments with their physical conditions.

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.

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%.

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.

Maintenance of multidomain neurocognitive functions in pediatric patients after proton beam therapy: A prospective case-series study

Proton Beam Therapy (PBT) was developed to minimize the harmful results of radiation therapy as treatment for brain tumors. This study examined the neurocognitive outcomes of PBT in pediatric patients. A total of 8 patients, who received either PBT or photon radiotherapy (XRT), were evaluated with multiple cognitive functions, which include intelligence, memory, executive functions, and attention. Most of patients performed average-to-superior levels of neurocognitive functions (NCF), except that a deterioration of executive functions was revealed in two patients receiving XRT. This study might be the first one to show the maintenance of multidomain NCF after PBT.

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.

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.

Frontal Assessment Battery as a Useful Tool to Differentiate Mild Cognitive Impairment due to Subcortical Ischemic Vascular Disease from Alzheimer Disease

BACKGROUND

Prominent executive dysfunction can differentiate vascular dementia from Alzheimer disease (AD). However, it is unclear whether the Frontal Assessment Battery (FAB) screening tool can differentiate subcortical ischemic vascular disease (SIVD) from AD at the pre-dementia stage. In addition, the neural correlates of FAB performance have yet to be clarified.

METHODS

Patients with mild cognitive impairment (MCI) due to SIVD (MCI-V), MCI due to AD (MCI-A), and demographically matched controls completed the Mini-Mental State Examination, Taiwanese FAB (TFAB), Category Fluency, and Chinese Version of the Verbal Learning Test, and underwent magnetic resonance imaging. White matter hyperintensities were rated according to the Scheltens scale.

RESULTS

TFAB total scale and its Orthographical Fluency subtest were the only measures that could differentiate MCI-V from MCI-A. Discriminative analysis showed that Orthographical Fluency scores successfully identified 73.2% of the cases with MCI-V, with 85.0% sensitivity. Orthographical Fluency scores were specifically associated with lesion load within frontal periventricular, frontal deep white matter, and basal ganglia regions.

CONCLUSION

The TFAB, and especially its 1-min Orthographical Fluency subtest, is a useful screening procedure to differentiate MCI due to SIVD from MCI due to AD. The discriminative ability is probably due to frontosubcortical white matter pathologies disproportionately involved in the two disease entities.

Method for enhancing the favored transverse-electric-polarized emission of an AlGaN deep-ultraviolet quantum well

An AlGaN quantum well (QW) structure of a deep-ultraviolet (UV) light-emitting diode (LED) needs to be well designed for controlling its band structure such that the heavy-hole (HH) band edge becomes lower than the split-off (SO) band edge and hence the transverse-electric (TE) polarization dominates the emission for achieving a higher light extraction efficiency. Here, we report the discovery of un-intentionally formed high-Al AlGaN nano-layers right above and below such a QW and their effects on the QW for changing the relative energy levels of the HH and SO bands. The comparison between the results of simulation study and polarization-resolved photoluminescence measurement confirms that the high-Al layers (HALs) represent the key to the observation of the dominating TE-polarized emission. By applying a stress onto a sample along its c-axis to produce a tensile strain in the c-plane for counteracting the HAL effects in changing the band structure, we can further understand the effectiveness of the HALs. The formation of the HALs is attributed to the hydrogen back-etching of Ga atoms during the temperature transition from quantum barrier growth into QW growth and vice versa. The Al filling in the etched vacancies results in the formation of an HAL. This discovery brings us with a simple method for enhancing the favored TE-polarized emission in an AlGaN deep-UV QW LED.

Quality of return to work in patients with mild traumatic brain injury: a prospective investigation of associations among post-concussion symptoms, neuropsychological functions, working status and stability

PRIMARY OBJECTIVE

Although 'return to work' (RTW) has been always emphasized for patients with mild traumatic brain injury (MTBI), methodological drawbacks weakened its representativeness. This study thus aims to evaluate the 'work quality' (WQ) which originated from 'working status' and 'working stability' simultaneously, and to further explore the associations among post-concussion symptoms (PCS), neuropsychological functions and WQ.

METHODS AND PROCEDURES

A total of 179 participants, which included 132 patients with MTBI and 47 healthy participants, were prospectively recruited. The work quality index (WQI) was developed to evaluate WQ. All patients were evaluated for their PCS, neuropsychological functions and WQ at two weeks post-injury (T1), while PCS and WQ were recorded by one month post-injury (T2).

RESULTS

More than half of the patients were not able to retain their pre-injury jobs at T1, while 26% of the patients still failed to regain previous works at T2. Interestingly, WQ was significantly associated with educational levels and physical PCS, such as headache and dizziness.

CONCLUSIONS

Simultaneously considering working status and stability to reveal the quality of RTW is merited. A higher educational level might be a protective factor for successful RTW, and ameliorating physical symptoms is also necessary to get favourable WQ by one month after MTBI.

Dependencies of surface plasmon coupling effects on the p-GaN thickness of a thin-p-type light-emitting diode

The high performance of a light-emitting diode (LED) with the total p-type thickness as small as 38 nm is demonstrated. By increasing the Mg doping concentration in the p-AlGaN electron blocking layer through an Mg pre-flow process, the hole injection efficiency can be significantly enhanced. Based on this technique, the high LED performance can be maintained when the p-type layer thickness is significantly reduced. Then, the surface plasmon coupling effects, including the enhancement of internal quantum efficiency, increase in output intensity, reduction of efficiency droop, and increase of modulation bandwidth, among the thin p-type LED samples of different p-type thicknesses that are compared. These advantageous effects are stronger as the p-type layer becomes thinner. However, the dependencies of these effects on p-type layer thickness are different. With a circular mesa size of 10 μm in radius, through surface plasmon coupling, we achieve the record-high modulation bandwidth of 625.6 MHz among c-plane GaN-based LEDs.

Cancer cell death pathways caused by photothermal and photodynamic effects through gold nanoring induced surface plasmon resonance

The different death pathways of cancer cells under the conditions of the photothermal (PT), effect, photodynamic (PD) effect, and their combination are evaluated. By incubating cells with Au nanoring (NRI) either linked with the photosensitizer, AlPcS, or not, the illumination of a visible continuous laser for exciting the photosensitizer or an infrared femtosecond laser for exciting the localized surface plasmon resonance of Au NRI, leads to various PT and PD conditions for study. Three different staining dyes are used for identifying the cell areas of different damage conditions at different temporal points of observation. The cell death pathways and apoptotic evolution speeds under different cell treatment conditions are evaluated based on the calibration of the threshold laser fluences for causing early-apoptosis (EA) and necrosis (NE) or late-apoptosis (LA). It is found that with the PT effect only, strong cell NE is generated and the transition from EA into LA is faster than that caused by the PD effect when the EA stage is reached within 0.5 h after laser illumination. By combining the PT and PD effects, in the first few hours, the transition speed becomes lower, compared to the case of the PT effect only, when both Au NRIs internalized into cells and adsorbed on cell membrane exist. When the Au NRIs on cell membrane is removed, in the first few hours, the transition speed becomes higher, compared to the case of the PD effect only.