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Tuberculosis (TB) of the genitourinary system is a rare form of extrapulmonary TB. Testicular TB is particularly uncommon among kidney transplantation (KT) recipients. Diagnosing testicular TB is challenging due to the nonspecific nature of clinical presentations and ambiguous imaging results. In this report, we describe a case involving a 36-year-old male KT recipient who presented with left scrotal pain. He had undergone a living donor KT 8 years prior and was receiving tacrolimus, mycophenolate mofetil, and prednisolone. Laboratory tests revealed anemia, leukocytosis, and elevated inflammatory markers. Computed tomography showed left scrotal wall thickening and enlargement, suggestive of a left testicular abscess. We discontinued mycophenolate mofetil and administered intravenous antibiotics. Additionally, we performed an incision and drainage of the abscess. However, there was no improvement in his clinical course. Consequently, we performed a radical left orchiectomy. The biopsy revealed extensive chronic granulomatous inflammation with caseous necrosis, consistent with tuberculous orchiepididymitis. A quadruple anti-TB regimen was administered, leading to an improvement in the patient's condition. To the best of our knowledge, this is the first reported case of testicular TB without other organ involvement in KT recipients. Including testicular TB in the differential diagnosis of testicular infections and masses is necessary to avoid unnecessary surgical procedures.

Abstract A conventional electrode composite for rechargeable zinc‐ion batteries (ZIBs) includes a binder for strong adhesion between the electrode material and the current collector. However, the introduction of a binder leads to electrochemical inactivity and low electrical conductivity, resulting in the decay of the capacity and a low rate capability. We present a binder‐ and conducting agent‐free VO2 composite electrode using in situ polymerization of dopamine on a flexible current collector of pyroprotein‐based fibers. The as‐fabricated composite electrode was used as a substrate for the direct growth of VO2 as a self‐supported form on polydopamine‐derived pyroprotein‐based fibers (pp‐fibers@VO2(B)). It has a high conductivity and flexible nature as a current collector and moderate binding without conventional binders and conducting agents for the VO2(B) cathode. In addition, their electrochemical mechanism was elucidated. Their energy storage is induced by Zn2+/H+ coinsertion during discharging, which can be confirmed by the lattice expansion, the formation of by‐products including Znx(OTf)y(OH)2x−y·nH2O, and the reduction of V4+ to V3+. Furthermore, the assembled Zn//pp‐fibers@VO2(B) pouch cells have excellent flexibility and stable electrochemical performance under various bending states, showing application possibilities for portable and wearable power sources.

Purpose: The proper treatment sequence for administering abiraterone acetate plus prednisolone (AAP) and chemotherapeutic agents has not yet been elucidated for metastatic castration-resistant prostate cancer (mCRPC). Hence, this study evaluated the effectiveness and safety of AAP in pre- and post-chemotherapy settings using real-world data. Materials and Methods: This prospective, multicenter, open-label, observational study included 506 patients with mCRPC. Patients were classified according to the timing of chemotherapy into pre- and post-chemotherapy groups. The effectiveness and safety of AAP were compared between the groups; the prostate-specific antigen (PSA) response, PSA progression-free survival, and radiologic progression-free survival were assessed; and adverse drug reactions were recorded. Results: Among the included patients, 319 and 187 belonged to the pre- and post-chemotherapy groups, respectively. Risk classification was similar between the two groups. The PSA response was 61.8% in the pre-chemotherapy group and 39.0% in the post-chemotherapy group (p

Electronic textile-based gas sensors with a high response for NO2 gas were fabricated using reduced graphene oxide (rGO)-coated commercial cotton fabric (rGOC). Graphene oxide (GO) was coated on cotton fabric by simply dipping the cotton into a GO solution. To investigate the relationship between the degree of reduction and the sensing response, the GO-coated fabrics were thermally reduced at various temperatures (190, 200, 300, and 400 °C). The change in the amount of oxygen functional groups on the rGOCs was observed by x-ray photoelectron spectroscopy, Raman spectroscopy, and x-ray diffraction patterns. The maximum sensing response of 45.90 % at 10 ppm of NO2 gas at room temperature was exhibited by the rGOC treated at 190 °C, which was the lowest heat-treatment temperature. The high response comes from the greater amount of oxygen functional groups compared to other rGOC samples, and the tubular structure of the cotton.

Abstract Human sterile α motif and HD domain-containing protein 1 (SAMHD1) has deoxyribonucleoside triphosphohydrolase (dNTPase) activity that allows it to defend against human immunodeficiency virus type I (HIV-1) infections and regulate the cell cycle. Although SAMHD1 mutations have been identified in various cancer types, their role in cancer is unclear. Here, we aimed to investigate the oncogenic role of SAMHD1 in human clear cell renal cell carcinoma (ccRCC), particularly as a core molecule promoting cancer cell migration. We found that SAMHD1 participated in endocytosis and lamellipodia formation. Mechanistically, SAMHD1 contributed to the formation of the endosomal complex by binding to cortactin. Thereafter, SAMHD1-stimulated endosomal focal adhesion kinase (FAK) signaling activated Rac1, which promoted lamellipodia formation on the plasma membrane and enhanced the motility of ccRCC cells. Finally, we observed a strong correlation between SAMHD1 expression and the activation of FAK and cortactin in tumor tissues obtained from patients with ccRCC. In brief, these findings reveal that SAMHD1 is an oncogene that plays a pivotal role in ccRCC cell migration through the endosomal FAK-Rac1 signaling pathway.

Many studies on flexible strain and pressure sensors have been reported due to growing interest in wearable devices for healthcare purposes. Here, we present flexible pressure and strain (motion) sensors prepared with only graphene oxide (GO) and commercial silk fabrics and yarns. The pressure sensors were fabricated by simply dipping the silk fabric into GO solution followed by applying a thermal treatment at 400 °C to obtain reduced GO (rGO). The pressure sensors were made from rGO-coated fabrics, which were stacked in three, five, and seven layers. A super-sensitivity of 2.58 × 103 kPa−1 at low pressure was observed in the seven-layer pressure sensor. The strain sensors were obtained from rGO-coated twisted silk yarns whose gauge factor was 0.307. Although this value is small or comparable to the values for other sensors, it is appropriate for motion sensing. The results of this study show a cost-effective and simple method for the fabrication of pressure and motion sensors with commercial silk and GO.

Purpose: To identify changes in prostate cancer (PCa) risk-stratification during the last two decades in Korea, where the social perception of PCa was limited due to a relatively low incidence but has recently been triggered by the rapidly increasing incidence of benign prostate hyperplasia. Materials and Methods: Retrospective data of patients who had received a diagnosis of PCa in a single Korean province (Daegu-Gyeongsangbuk) at all seven training hospitals in the years 2003, 2007, 2011, 2015, 2019, and 2021 were subjected to analysis. Changes in PCa risk-stratification were investigated with respect to serum prostate-specific antigen (PSA), Gleason score (GS), and clinical stage. Results: Of the 3,393 study subjects that received a diagnosis of PCa, 64.1% had high-risk disease, 23.0% intermediate, and 12.9% low-risk disease. The proportion diagnosed with high-risk disease was 54.8% in 2003, 30.6% in 2019, but then increased to 35.1% in 2021. The proportion of patients with high PSA (>20 ng/mL) steadily decreased from 59.4% in 2003 to 29.6% in 2021, whereas the proportion with a high GS (>8) increased from 32.8% in 2011 to 34.0% in 2021, and the proportion with advanced stage disease (over cT2c) increased from 26.5% in 2011 to 37.1% in 2021. Conclusions: In this retrospective study, conducted in a single Korean province, high-risk PCa accounted for the largest proportion of newly registered Korean PCa patients during the last two decades and increased in the early 2020s. This outcome supports the adoption of nationwide PSA screening, regardless of current Western guidelines.

Background: We aimed to evaluate the current status of first-line treatment options for prostate cancer in patients aged ≥75 years in Korea. Materials and methods: The study included 873 patients diagnosed with biopsy-proven prostate cancer at 5 institutions in Korea from January 2009 to December 2018. Inclusion criteria were aged ≥75 years at diagnosis, prostate biopsy with ≥12 cores, and follow-up period ≥1 year. Clinical data were retrospectively collected from electronic medical records. Results: Primary treatment for prostate cancer in patients aged ≥75 years included androgen deprivation therapy (ADT) (n = 614), radical prostatectomy (RP) (n = 114), and radiation therapy (n = 62). Among patients with RP, nine patients received ADT before RP. The RP group was younger with better Eastern Cooperative Oncology Group Performance Status (ECOG PS), lower initial prostate-specific antigen (PSA), Gleason score (GS), max percent positive cores, less positive cores, and less advanced clinical Tumor Node Metastasis (TNM) stage compared with the ADT group. Multivariate analysis showed that age, ECOG PS, and PSA were independent prognostic factors for RP. When the ADT group was classified by therapeutic regimens, the most common therapeutic regimen was maximal androgen blockade (MAB) (n = 571), and leuprolide + bicalutamide (n = 330) was the most common MAB regimen. Multivariate analysis for secondary treatment showed that age, ECOG PS, GS, and clinical N1 or M1 stage were independent predictive factors. Enzalutamide was the most preferred treatment for tertiary treatment. Conclusion: In patients with prostate cancer aged ≥75 years, the most common treatment option was MAB, and the leuprolide + bicalutamide was the most common MAB regimen. Age, ECOG PS, and PSA are the useful indicators of surgical treatment, which increased during the study period. Younger patients with high GS and advanced clinical stage were more likely to undergo secondary treatment.

Though prostate cancer (PCa) is the second most common cancer world widely, there exist substantial differences exist between Asia and the west. Genetic susceptibility and lifestyle may contribute to disproportionately lower incidences and mortalities of PCa in Asian countries, but the differences in diagnostic practices are also likely to contribute, and a large part of them may be explained by the lesser chance of prostate-specific antigen (PSA) testing. In the US, about half of men aged over 50 years had been exposed to the screening test in the early 2000s. The shifts in the risk stratification from the high-risk dominant disease in the late 1980s to the low-risk dominant disease in the early 2000s led to criticism regarding the unconditional nature of PSA-based screening. Based on the conflicting outcomes from the randomized clinical trials which investigated the benefit of PSA testing, US Preventive Study Task Force recommended ceasing mass screening in 2012. Accordingly, guidelines begin to emphasize shared decision-making on the PSA testing narrowing their scopes to men aged 55 to 69 years since 2013. Though most Asian countries have not begun to recognize PCa as a major agenda item until the 2010s, a clear trend of expanding incidence of it implies that the time to come to reconsider PSA testing as a higher priority in the public health sphere in the 2020s. Concerns regarding over-diagnosis and over-treatment of insignificant diseases are imperative. However, the distinctive epidemiologic characteristics of PCa in Asia areas, such as low exposure to the repetitive PSA testing, the recent increase in its incidence driven by the elderly and super-elderly, and racial differences should be considered when it comes to the establishment of screening policy utilizing PSA test.

Background: Holmium laser enucleation of the prostate (HoLEP) and robotic-assisted simple prostatectomy (RASP) are the two most important therapeutic modalities for large benign prostatic hyperplasia. However, there are currently no studies comparing these two treatments in a Korean setting. In this study, the authors seek to compare the safety and efficacy associated with these procedures. Methods: The authors retrospectively analyzed 59 male patients who underwent HoLEP (n = 26) or RASP (n = 33) at single center. The following preoperative data were compared: age, the International Prostatic Symptom Score (IPSS), transrectal ultrasonography, uroflowmetry, and hemoglobin. Intraoperative data included operation time and specimen weight. Postoperative data included change in IPSS, uroflowmetry, and hemoglobin. Length of stay, catheterization time, and complications were also reviewed. Results: No significant differences between the two groups were found in terms of age, total prostate, and transitional volume. Postoperatively, both groups showed similar improvement in the maximum flow rate, post-void residual urine, IPSS, and quality of life. Intraoperatively, there were no differences regarding operation time and resected prostate volume. Catheter removal time and length of stay were significantly shorter in the HoLEP group than the RASP group. In addition, postoperative hemoglobin changes were significantly lower in the HoLEP group. However, incontinence rates at 1 month and 2 months postoperative in the RASP group were lower than the HoLEP group. Conclusions: Both HoLEP and RASP can produce excellent postoperative outcomes. However, catheter removal time, length of stay, and hemoglobin changes were more favorable in the HoLEP group. On the other hand, postoperative incontinence was more favorable in the RASP group. These factors must be heavily considered when deciding surgical the method for large benign prostatic hyperplasia.

Purpose: To document nationwide serum prostate-specific antigen (PSA) testing trends over the past decade and to investigate the impact of testing on prostate cancer (PCa) detection. Materials and Methods: Using annual National Health Insurance Service of Korea data for the period 2006 to 2016, PSA testing rates were investigated for men aged ≥40 years by decade, and associations between test rates and registered PCa cases were analyzed. Results: During the study period, the incidence of PCa increased about threefold (4,415 in 2006 to 15,046 in 2016). PCa incidences increased with age (p

This report describes the case of a 65-year-old man who presented with gross hematuria and a history of pelvic salvage radiotherapy for prostate cancer. Cystoscopy and transurethral resection of the bladder revealed urothelial carcinoma. Subsequently, disseminated bone metastases were detected with normal prostate-specific antigen (PSA) levels, and palliative radiotherapy and systemic chemotherapy were administered. Because gross hematuria can appear in both acute/chronic cystitis and bladder cancer in patients who have undergone pelvic radiotherapy for prostate cancer, close follow-up along with a detailed evaluation is needed. In addition, because prostate cancer disease progression with normal PSA levels may be associated with specific pathological findings, a detailed evaluation of symptoms and a careful review of pathologic reports are important.

Objectives: We investigated the relationship between tumor characteristics and visible tumors on magnetic resonance imaging (MRI) and examined the prognosis of tumor detection on MRI compared with no tumor detection in localized prostate cancer. Materials and methods: We reviewed 214 patients with pT2N0M0 prostate cancer who underwent radical prostatectomy between January 2009 and December 2016. All the patients underwent MRI preoperatively. The patients were divided into 2 groups postoperatively: no visible tumor on the MRI group (n = 96, 44.9%) and visible tumor on the MRI group (n = 118, 55.1%). The visible tumor was defined as Prostate Imaging Reporting and Data System, version 2 Grade ≥ 3 on MRI. Age, prostate-specific antigen, prostate volume, positive surgical margin (PSM), lymphovascular invasion, and biochemical recurrence (BCR) were compared between the 2 groups. We also assessed the relationship between visible tumors on MRI and oncologic characteristics. Results: The visible tumor on the MRI group showed a higher Gleason score ≥4 + 3 [45.8% versus (vs.) 17.7%], high frequency of postoperative PSMs (28.8% vs. 16.7%), and higher BCR rate (17.8% vs. 7.3%) than the no visible tumor on the MRI group. The Kaplan–Meier analysis for BCR-free survival also showed a significant difference (P = 0.006). In multivariate Cox regression analysis, the detection of tumors on MRI was associated with a higher BCR risk [hazard ratio: 3.35; 95% confidence interval (CI): 1.36-8.27; P = 0.009]. We found a positive association between visible tumors on MRI and primary Gleason pattern of ≥4 (odds ratio: 4.31; 95% CI: 2.21–8.40; P

Purpose: To analyze the efficacy and safety of standard-dose antimuscarinic treatment on male patients with overactive bladder (OAB) symptoms showing poor efficacy after low-dose antimuscarinics. Materials and Methods: We retrospectively reviewed the data of 566 male patients aged ≥40 with OAB symptoms between January 2017 and June 2018. They were treated with low-dose antimuscarinics for at least 4 weeks and showed poor efficacy; therefore, they were switched to standard dose antimuscarinic treatment (5 mg of solifenacin) for ≥12 weeks. The international prostate symptom score (IPSS) and overactive bladder symptom score (OABSS) at baseline (V0), 4 weeks (V1), and 12 weeks (V2) were analyzed. Post void residual urine volume (PVR) was also recorded. Results: The median age, body mass index, and prostate-specific antigen levels were 69.0 years, 24.2 kg/m2, and 1.24 ng/dL, respectively. The mean value of the total IPSS and OABSS significantly decreased between V0 and V2 (from 16.73 to 13.69 and 7.33 to 5.34, respectively, all p

In the oxidative dehydrogenation (ODH) process that converts ethylbenzene to styrene, vanadium-based catalysts, especially V2O5, are used in a CO2 atmosphere to enhance process efficiency. Here we demonstrate that the activation energy of V2O5 can be manipulated by exposure to high pressure CO2, using V2O5 nanowires (VON). The oxidation of V4+ to V5+ was observed by X-ray photoelectron spectroscopy. The ratio of V4+/V5+ which the typical comparable feature decreased 73.42%. We also found an increase in the interlayer distance in VON from 9.95 Å to 10.10 Å using X-ray diffraction patterns. We observed changes in the peaks of the stretching mode of bridging triply coordinated oxygen (V3O), and the bending vibration of the bridging VOV, using Raman spectroscopy. We confirmed this propensity by measuring the CO2 pressure-dependent conductance of VON, up to 45 bar. 92.52% of decrease in the maximum conductance compared with that of the pristine VON was observed. The results of this study suggest that ODH process performance can be improved using the VON catalyst in a high pressure CO2 atmosphere.

Background: We hypothesized that prostatic anatomical factors may affect the progression of benign prostatic hyperplasia (BPH) and analyzed whether prostatic anatomical factors could be predictive of the risk of surgery. Materials and methods: From February to October 2014, 679 men older than 40 years who had lower urinary tract symptoms and enlarged prostates were enrolled from five medical centers. Patients' medical characteristics, serum prostate-specific antigen levels, transrectal ultrasound (TRUS) results, and uroflowmetry were analyzed. Using TRUS in all patients, the total prostate volume, transitional zone volume, prostatic urethral length, transitional zone urethral length, intravesical prostatic protrusion, and prostatic urethral angle were measured. Logistic regression analysis was used to determine factors associated with the risk of surgery. Receiver operating characteristic curves were used to determine cutoff values for significant variables. Results: Of 679 patients, 37 (5.4%) underwent BPH-related surgery. Prostatic urethral length and transitional zone urethral length were independently associated with the risk of surgery. Age, serum prostate-specific antigen levels, peak flow rate, postvoid residual urine, and other anatomical factors determined by TRUS were not statistically significant with respect to the risk of surgery. Using receiver operating characteristic curve–based predictions, the best cutoff values for prostatic and transitional zone urethral length were 4.53 cm (sensitivity: 83.3%, specificity: 61.6%) and 3.35 cm (sensitivity: 83.3%, specificity: 77.9%), respectively. Conclusions: This study showed that patients with BPH with longer prostatic and transitional zone urethral lengths had a higher risk of surgery. Prostatic and transitional zone urethral length may be useful predictive factors for medical treatment failure in patients with BPH. Keywords: Benign prostatic hyperplasia, Risk factors, Treatment failure, Ultrasonography

The mechanical properties of silk are determined by tight stacks of sheet-like peptide crystals distributed in amorphous regions. Here, the authors heat and stretch silk fibres to align these crystal into a long range ordered carbon structure and dramatically enhance the silk strength.

Purpose: Update and reanalysis of our experience of active surveillance (AS) for prostate cancer (PCa) in Korea. Materials and Methods: A prospective, single-arm, cohort study was initiated in January 2008. Patients were selected according to the following criteria: Gleason sum ≤6 with single positive core with ≤30% core involvement, clinical stage≤T1c, prostate-specific antigen (PSA)≤10 ng/mL, and negative magnetic resonance imaging (MRI) results. Follow-up was by PSA measurement every 6 months, prostate biopsies at 1 year and then every 2–3 years, and MRI every year. Results: A total of 80 patients were treated with AS. Median follow-up was 52 months (range, 6–96 months). Of them, 39 patients (48.8%) discontinued AS for various reasons (17, disease progression; 9, patient preference; 10, watchful waiting due to old age; 3, follow-up loss; 2, death). The probability of progression was 14.0% and 42.9% at 1 and 3 years, respectively. Overall survival was 97.5%. PCa-specific survival was 100%. Progression occurred in 5 of 7 patients (71.4%) with a prostate volume less than 30 mL, 7 of 40 patients (17.5%) with a prostate volume of 30 to 50 mL, and 5 of 33 patients (15.2%) with a prostate volume of 50 mL or larger. There were 8 detectable positive lesions on follow-up MRI. Of them, 6 patients (75%) had actual progressed disease. Conclusions: Small prostate volume was associated with a tendency for cancer progression. MRI was helpful and promising for managing AS. Nevertheless, regular biopsies should be performed. AS is a safe and feasible treatment option for very-low-risk PCa in Korea. However, AS should continue to be used in carefully selected patients.

Background: We evaluated ultrasonography variables associated with the improvement of nocturia after administration of alpha adrenoceptor antagonist (alpha blocker) monotherapy. Methods: From February to October 2014, 679 men with lower urinary tract symptoms (LUTS) underwent ultrasonography including prostate volume, transitional zone volume, prostatic urethral length, the ratio between prostatic urethral length and prostate volume (RPUL), intravesical prostatic protrusion (IPP), and prostatic urethral angle (PUA). Among them, 108 men who had pre-treatment nocturia without nocturnal polyuria (nocturnal polyuria index

We investigated the gas storage capacity of thermally carbonized and chemically activated Phyllostachys bambusoides (PB), which is a nature-derived green carbon with an organic porous structure. Samples were thermally treated at 900 °C for 24 h, and then were chemically activated with different amounts of KOH. The pore distribution, surface area, and H2 storage capacity were measured by N2 and H2 gas sorption, up to 847 mmHg (1.13 bar) at 77 K. The CO2 storage capacity was measured up to 847 mmHg (1.13 bar) at 298 K. The maximum gas storage was shown in the sample activated with 6 times gravimetric ratio of chemical agent. It reached 1.86 wt% for H2 and 3.44 mmol/g for CO2. We used multilateral analysis methods (XRD, XPS, Raman spectroscopy, and scanning electron microscope) to identify the factors influencing gas sorption. We found that the amount of oxygen groups influence the enhancement of gas storage capacity. Moreover, the results showed that PB-based porous activated carbon has the potential to be used as a multirole gas storage material.

Twisted bilayer graphene (tBLG) is two stacked single graphene sheets rotated at a specific angle. The twist angle plays an important role in the physical properties of the tBLG. In this study, we analyzed the interaction distance between two graphene layers in tBLG using Raman spectroscopy and atomic force microscopy. To confirm the interaction of the upper and bottom graphenes in the tBLG, we prepared two tBLGs with twist angles of 5° and 24°. The interlayer distance was controlled by depositing a gold bar between the two graphene layers. We found that the decoupling interlayer distance of the tBLG was different depending on the twist angle (0.74 nm for 5° and 1.66 nm for 24°). This indicates that the interaction between two graphene layers is strongly coupled with small twist angle, as expected.

BackgroundHip fracture surgery on elderly patients is associated with a high incidence of morbidity and mortality. The aim of this study is to identify the risk factors related to the postoperative mortality and complications following hip fracture surgery on elderly patients.MethodsIn this retrospective study, the medical records of elderly patients (aged 65 years or older) who underwent hip fracture surgery from January 2011 to June 2014 were reviewed. A total of 464 patients were involved. Demographic data of the patients, American Society of Anesthesiologists physical status, preoperative comorbidities, type and duration of anesthesia and type of surgery were collected. Factors related to postoperative mortality and complications; as well as to intensive care unit admission were analyzed using logistic regression.ResultsThe incidence of postoperative mortality, cardiovascular complications, respiratory complications and intensive care unit (ICU) admission were 1.7, 4.7, 19.6 and 7.1%, respectively. Postoperative mortality was associated with preoperative respiratory comorbidities, postoperative cardiovascular complications (P < 0.05). Postoperative cardiovascular complications were related to frequent intraoperative hypotension (P

N-type graphene fabricated by exposure to hydrogen gas has been previously studied. Based on this property of graphene, herein, we demonstrate local doping in single-layer graphene using selective adsorption of dissociative hydrogen at 350 K. A graphene field effect transistor was produced covered with PMMA on half of the graphene region. The charge neutrality point of the PMMA-window region shifted to a negative gate voltage (VG) region prominently compared with that of the PMMA-covered region. Consequently, a single graphene p-n junction was obtained by measuring the VG-dependent resistance of the whole graphene region. This method presents opportunities for developing and controlling the electronic structure of graphene and device applications.

The photocatalytic activity on decomposition of Rhodamine B (RB) of titanate nanotubes (TNTs) synthesized by alkali hydrothermal treatment method was evaluated using a microwave/UV/photocatalyst hybrid system. The effects of each element technique as well as the synergy effects on decomposition of organic material were investigated. When TNTs were ion-exchanged with HCl, Na+ content was reduced from 8.36 wt% to 0.03 wt%, whereas the TNTs calcined at 723 K was phase-transformed into anatase structure. The RB decomposition rate increased with TNTs dosage as well as with microwave intensity. Effect of addition of auxiliary oxidants on photocatalytic decomposition of RB was also investigated. When ozone was added, the decomposition rate increased with the amount of ozone added. When H2O2 was used as the auxiliary oxidant, however, addition of H2O2 exceeding a threshold amount caused reduction of decomposition rate. A synergy effect was observed when H2O2 addition was combined with microwave-assisted photocatalysis.

Experimental results of photocatalysis under high dissolved oxygen (DO) concentration conditions are reported. Methylene blue was used as the organic pollutant to be degraded by a novel microwave/UV/DO/TiO2 photocatalyst hybrid system. The degradation rate increased with TiO2 nanoparticle dosages and DO concentration. However, inhibition of photocatalysis due to bubbles produced by DO generator was also observed. When the DO generator was used to increase the DO concentration in the pollutant solution treated by the microwave-assisted UV-TiO2 photocatalysis, the decomposition rate constant was highest among all the experimental conditions tested in this study. This result demonstrated that high concentration of DO can enhance the photocatalytic reaction rate by causing a synergistic effect of constituent techniques.

Humidity-dependent current–voltage (I–V) characteristics of Pd-doped vanadium pentoxide nanowires (Pd-VONs) were investigated. Electrical quadruple hysteresis (QH) was observed and attributed to the large amount of water molecules adsorbed on the nanowires. Using QH in Pd-VONs, the reaction of water with PdO was interpreted as the water molecules are desorbed and then dissociated with increasing bias voltage. Owing to the dissociated H+ and OH− ions, PdO is reduced and oxidized. As a result, water molecules recombine as the bias voltage is decreased.