Symmetry-Mismatched SBU Transformation in MOFs: Postsynthetic Metal Exchange from Zn to Fe and Its Effects on Gas Adsorption and Dye Selectivity.

This research explores the alteration of metal-organic frameworks (MOFs) using a method called postsynthetic metal exchange. We focus on the shift from a Zn-based MOF containing a [Zn4O(COO)6] secondary building unit (SBU) of octahedral site symmetry (ANT-1(Zn)) to a Fe-based one with a [Fe3IIIO(COO)6]+ SBU of trigonal prismatic site symmetry (ANT-1(Fe)). The symmetry-mismatched SBU transformation cleverly maintains the MOF's overall structure by adjusting the conformation of the flexible 1,3,5-benzenetribenzoate linker to alleviate the framework strain. The process triggers a decrease in the framework volume and pore size alongside a change in the framework's charge. These alterations influence the MOF's ability to adsorb gas and dye. During the transformation, core-shell MOFs (ANT-1(Zn@Fe)) are formed as intermediate products, demonstrating unique gas sorption traits and adjusted dye adsorption preferences due to the structural modifications at the core-shell interface. Heteronuclear clusters, located at the framework interfaces, enhance the heat of CO2 adsorption. Furthermore, they also influence the selectivity of the dye size. This research provides valuable insights into fabricating novel MOFs with unique properties by modifying the SBU of a MOF with flexible organic linkers from one site symmetry to another.

Effects of Silica Shell Encapsulated Nanocrystals on Active χ-Fe5C2 Phase and Fischer-Tropsch Synthesis.

Among various iron carbide phases, χ-Fe5C2, a highly active phase in Fischer-Tropsch synthesis, was directly synthesized using a wet-chemical route, which makes a pre-activation step unnecessary. In addition, χ-Fe5C2 nanoparticles were encapsulated with mesoporous silica for protection from deactivation. Further structural analysis showed that the protective silica shell had a partially ordered mesoporous structure with a short range. According to the XRD result, the sintering of χ-Fe5C2 crystals did not seem to be significant, which was believed to be the beneficial effect of the protective shell providing restrictive geometrical space for nanoparticles. More interestingly, the protective silica shell was also found to be effective in maintaining the phase of χ-Fe5C2 against re-oxidation and transformation to other iron carbide phases. Fischer-Tropsch activity of χ-Fe5C2 in this study was comparable to or higher than those from previous reports. In addition, CO2 selectivity was found to be very low after stabilization.

Dissociating stable nitrogen molecules under mild conditions by cyclic strain engineering.

All quiet on the nitrogen front. The dissociation of stable diatomic nitrogen molecules (N2) is one of the most challenging tasks in the scientific community and currently requires both high pressure and high temperature. Here, we demonstrate that N2 can be dissociated under mild conditions by cyclic strain engineering. The method can be performed at a critical reaction pressure of less than 1 bar, and the temperature of the reaction container is only 40°C. When graphite was used as a dissociated N* receptor, the normalized loading of N to C reached as high as 16.3 at/at %. Such efficient nitrogen dissociation is induced by the cyclic loading and unloading mechanical strain, which has the effect of altering the binding energy of N, facilitating adsorption in the strain-free stage and desorption in the compressive strain stage. Our finding may lead to opportunities for the direct synthesis of N-containing compounds from N2.

Adsorption and Oxidative Desorption of Acetaldehyde over Mesoporous Fe x O y H z /Al2O3.

Fe x O y H z nanostructures were incorporated into commercially available and highly porous alumina using the temperature-regulated chemical vapor deposition method with ferrocene as an Fe precursor and subsequent annealing. All processes were conducted under ambient pressure conditions without using any high-vacuum equipment. The entire internal micro- and mesopores of the Al2O3 substrate with a bead diameter of ∼2 mm were evenly decorated with Fe x O y H z nanoparticles. The Fe x O y H z /Al2O3 structures showed substantially high activity for acetaldehyde oxidation. Most importantly, Fe x O y H z /Al2O3 with a high surface area (∼200 m2/g) and abundant mesopores was found to uptake a large amount of acetaldehyde at room temperature, and subsequent thermal regeneration of Fe x O y H z /Al2O3 in air resulted in the emission of CO2 with only a negligibly small amount of acetaldehyde because Fe x O y H z nanoparticles can catalyze total oxidation of adsorbed acetaldehyde during the thermal treatment. Increase in the humidity of the atmosphere decreased the amount of acetaldehyde adsorbed on the surface due to the competitive adsorption of acetaldehyde and water molecules, although the adsorptive removal of acetaldehyde and total oxidative regeneration were verified under a broad range of humidity conditions (0-70%). Combinatory use of room-temperature adsorption and catalytic oxidation of adsorbed volatile organic compounds using Fe x O y H z /Al2O3 can be of potential application in indoor and outdoor pollution treatments.

Giant thermal hysteresis in Verwey transition of single domain Fe3O4 nanoparticles.

Most interesting phenomena of condensed matter physics originate from interactions among different degrees of freedom, making it a very intriguing yet challenging question how certain ground states emerge from only a limited number of atoms in assembly. This is especially the case for strongly correlated electron systems with overwhelming complexity. The Verwey transition of Fe3O4 is a classic example of this category, of which the origin is still elusive 80 years after the first report. Here we report, for the first time, that the Verwey transition of Fe3O4 nanoparticles exhibits size-dependent thermal hysteresis in magnetization, 57Fe NMR, and XRD measurements. The hysteresis width passes a maximum of 11 K when the size is 120 nm while dropping to only 1 K for the bulk sample. This behavior is very similar to that of magnetic coercivity and the critical sizes of the hysteresis and the magnetic single domain are identical. We interpret it as a manifestation of charge ordering and spin ordering correlation in a single domain. This work paves a new way of undertaking researches in the vibrant field of strongly correlated electron physics combined with nanoscience.

Prognostic value of preoperative systemic inflammation markers in localized upper tract urothelial cell carcinoma: a large, multicenter cohort analysis.

BACKGROUND: The aim of this study was to investigate the prognostic value of preoperative systemic inflammation markers in upper tract urothelial carcinoma (UTUC). METHODS: A total of 1137 patients who underwent radical nephroureterectomy with bladder cuff excision at 9 institutions from 2004 to 2015, were retrospectively reviewed. The Glasgow Prognostic Score (GPS), modified GPS (mGPS), neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR) for each patient were calculated. Univariable and multivariable analysis was performed using the Cox proportional hazards regression model. Cut-off values for NLR and PLR were calculated using a receiver operating characteristic curve. RESULTS: The median follow-up period was 39.1 (interquartile range: 18.3-63.8) months. Univariable analysis revealed that GPS, mGPS, PLR, and NLR (all, P=0.001) were significantly associated with both recurrence-free survival (RFS) and cancer-specific survival (CSS). Multivariable analysis revealed that GPS (P=0.001), PLR (hazards ratio [HR] =1.32; 95% CI: 1.08-1.62, P=0.007 and HR =1.87; 95% CI: 1.21-2.92, P=0.005), NLR (HR =1.38; 95% CI: 1.12-1.69, P=0.003 and HR =1.70; 95% CI: 1.10-2.62, P=0.017) were significantly associated with RFS and CSS. CONCLUSIONS: Our results suggest that preoperative systemic inflammation markers such as GPS, PLR, and NLR are independent prognostic factors in patients with UTUC after surgery.

Is preoperative chronic kidney disease status associated with oncologic outcomes in upper urinary tract urothelial carcinoma? A multicenter propensity score-matched analysis.

PURPOSE: The aim of this study was to determine the effect of preoperative chronic kidney disease (CKD) on the prognosis of patients with upper urinary tract urothelial carcinoma (UTUC) who had undergone radical nephroureterectomy (RNU). RESULTS: The median follow-up period was 31.1 months (interquartile range: 16.2-55.7 months). Among the study patients, 224 patients in the non-CKD group were selected via propensity score matching. The median recurrence-free, cancer-specific, and overall survival were significantly shorter for patients with preoperative CKD than for non-CKD patients (p = 0.001, p = 0.001, and p = 0.001, respectively). According to multivariable Cox regression analysis, preoperative CKD was related to worse recurrence-free (hazard ratio [HR]: 1.81, 95% confidence interval [CI]: 1.15-2.86, p = 0.011), cancer-specific (HR: 2.44, 95% CI: 1.44-4.14, p = 0.001), and overall survival (HR: 1.66, 95% CI: 1.15-2.40, p = 0.007). METHODS: A total of 566 patients who underwent RNU at 6 institutions from 2004 to 2014 were retrospectively reviewed. Of these patients, 342 had an estimated glomerular filtration rate (eGFR) ≥ 60 ml/min/1.73 m2 (non-CKD group) and 224 patients had an eGFR <60 ml/min/1.73 m2 (CKD group). To adjust for potential baseline confounders, 224 patients in the non-CKD group were selected by propensity matching. Clinicopathological variables and survival rates were compared between the 2 groups. CONCLUSIONS: Preoperative CKD appears to be an important independent prognostic factor for oncologic outcomes in patients with UTUC.

Survival of Verwey transition in gadolinium-doped ultrasmall magnetite nanoparticles.

We have demonstrated that the Verwey transition, which is highly sensitive to impurities, survives in anisotropic Gd-doped magnetite nanoparticles. Transmission electron microscopy analysis shows that the nanoparticles are uniformly distributed. X-ray photoelectron spectroscopy and EDS mapping analysis confirm Gd-doping on the nanoparticles. The Verwey transition of the Gd-doped magnetite nanoparticles is robust and the temperature dependence of the magnetic moment (zero field cooling and field cooling) shows the same behaviour as that of the Verwey transition in bulk magnetite, at a lower transition temperature (∼110 K). In addition, irregularly shaped nanoparticles do not show the Verwey transition whereas square-shaped nanoparticles show the transition. Mössbauer spectral analysis shows that the slope of the magnetic hyperfine field and the electric quadrupole splitting change at the same temperature, meaning that the Verwey transition occurs at ∼110 K. These results would provide new insights into understanding the Verwey transition in nano-sized materials.

The De Ritis (aspartate transaminase/alanine transaminase) ratio as a predictor of oncological outcomes in patients after surgery for upper urinary tract urothelial carcinoma.

PURPOSE: Recently, several studies have shown that the De Ritis ratio (aspartate transaminase/alanine transaminase) can be a useful prognostic biomarker for certain types of malignant tumors. However, the prognostic value of the De Ritis ratio in patients with upper tract urothelial carcinoma remains largely unknown. The aim of the present study was to evaluate the prognostic significance of the De Ritis ratio in patients who had undergone radical nephroureterectomy (RNU) for upper urinary tract urothelial carcinoma. METHODS: In total, 1049 patients who underwent RNU at eight institutions from 2004 to 2015 were reviewed retrospectively. The De Ritis ratio and conventional clinicopathological parameters were analyzed. Survival analysis was performed using the Kaplan-Meier method and log-rank test. Multivariate analysis was carried out using the Cox proportional hazards regression model. De Ritis ratio cutoff values were derived from receiver operating characteristic (ROC) curves. RESULTS: ROC analysis showed the cutoff De Ritis ratio for overall death to be 1.6 (p = 0.002). The cancer-specific survival (CSS) and overall survival (OS) were significantly shorter for patients with a high De Ritis ratio (>1.6). Multivariate analysis revealed an independent relationship between an increased De Ritis ratio (>1.6) and shorter CSS (hazard ratio, HR 2.49, 95% confidence interval, CI 1.70-3.64; p = 0.001) and OS (HR 1.84, 95% CI 1.34-2.52; p = 0.001). CONCLUSION: The De Ritis ratio can be a significant predictor of oncological outcomes in patients with upper urinary tract urothelial carcinoma after surgery.

A General Approach to Preferential Formation of Active Fe-Nx Sites in Fe-N/C Electrocatalysts for Efficient Oxygen Reduction Reaction.

Iron-nitrogen on carbon (Fe-N/C) catalysts have emerged as promising nonprecious metal catalysts (NPMCs) for oxygen reduction reaction (ORR) in energy conversion and storage devices. It has been widely suggested that an active site structure for Fe-N/C catalysts contains Fe-Nx coordination. However, the preparation of high-performance Fe-N/C catalysts mostly involves a high-temperature pyrolysis step, which generates not only catalytically active Fe-Nx sites, but also less active large iron-based particles. Herein, we report a general "silica-protective-layer-assisted" approach that can preferentially generate the catalytically active Fe-Nx sites in Fe-N/C catalysts while suppressing the formation of large Fe-based particles. The catalyst preparation consisted of an adsorption of iron porphyrin precursor on carbon nanotube (CNT), silica layer overcoating, high-temperature pyrolysis, and silica layer etching, which yielded CNTs coated with thin layer of porphyrinic carbon (CNT/PC) catalysts. Temperature-controlled in situ X-ray absorption spectroscopy during the preparation of CNT/PC catalyst revealed the coordination of silica layer to stabilize the Fe-N4 sites. The CNT/PC catalyst contained higher density of active Fe-Nx sites compared to the CNT/PC prepared without silica coating. The CNT/PC showed very high ORR activity and excellent stability in alkaline media. Importantly, an alkaline anion exchange membrane fuel cell (AEMFC) with a CNT/PC-based cathode exhibited record high current and power densities among NPMC-based AEMFCs. In addition, a CNT/PC-based cathode exhibited a high volumetric current density of 320 A cm-3 in acidic proton exchange membrane fuel cell. We further demonstrated the generality of this synthetic strategy to other carbon supports.

Poor Preoperative Glycemic Control Is Associated with Dismal Prognosis after Radical Nephroureterectomy for Upper Tract Urothelial Carcinoma: A Korean Multicenter Study.

PURPOSE: The purpose of this study is to evaluate the effect of diabetes mellitus (DM) and preoperative glycemic control on prognosis in Korean patients with upper tract urothelial carcinoma (UTUC) who underwent radical nephroureterectomy (RNU). MATERIALS AND METHODS: A total of 566 patients who underwent RNU at six institutions between 2004 and 2014 were reviewed retrospectively. Kaplan-Meier and Cox regression analyses were performed to assess the association between DM, preoperative glycemic control, and recurrence-free, cancer-specific, and overall survival. RESULTS: The median follow-up period was 33.8 months (interquartile range, 41.4 months). A total of 135 patients (23.8%) had DM and 67 patients (11.8%) had poor preoperative glycemic control. Patients with poor preoperative glycemic control had significantly shorter median recurrence-free, cancer-specific, and overall survival than patients with good preoperative glycemic control and non-diabetics (all, p=0.001). In multivariable Cox regression analysis, DM with poor preoperative glycemic control showed association with worse recurrence-free survival (hazard ratio [HR], 2.26; 95% confidence interval [CI], 1.31 to 3.90; p=0.003), cancer-specific survival (HR, 2.96; 95% CI, 1.80 to 4.87; p=0.001), and overall survival (HR, 2.13; 95% CI, 1.40 to 3.22; p=0.001). CONCLUSION: Diabetic UTUC patients with poor preoperative glycemic control had significantly worse oncologic outcomes than diabetic UTUC patients with good preoperative glycemic control and non-diabetics. Further investigation is needed to elucidate the exact mechanism underlying the impact of glycemic control on UTUC treatment outcome.

Characteristics of urinary retention in female inpatients managed with medical treatments.

PURPOSE: We aimed to analyze the characteristics of urinary retention (UR) in female inpatients managed with medical treatments. MATERIALS AND METHODS: We retrospectively analyzed the medical records of female inpatients referred to the department of urology for UR at our institution from January 2009, to December 2014. UR was defined as a difficulty in self-voiding despite a sufficient urine volume or >300-mL postvoid residual. The data included patients' age, body mass index (BMI), ambulatory status, medical and surgical history, classes of taking drugs, and urinary tract infection. RESULTS: A total of 182 women were included as retention group, mean age of 72.64±12.94 years and BMI of 22.94±3.10 kg/m(2). In the chi-square analysis, cardiovascular disorders (p=0.000), diabetes mellitus (p=0.008), metastatic malignancy (p=0.008), chronic renal disorders (p=0.028) were found significantly. In the multiple logistic regression analysis, cardiovascular disorders (p=0.002; odds ratio [OR], 0.491), metastatic malignancy (p=0.013; OR, 2.616) were found to increase the risk of UR. The most common surgical history was anti-incontinence surgery (7.2%). In term of medication use, the most prescribed agents were nonsteroidal anti-inflammatory drugs (NSAIDs) (53.8%). The patients taking multiple drugs with antimuscarinic effects except of NSAIDs, narcotics and diuretics were 48 (26.4%). Urinary tract infection was identified in 43 patients (23.6%). CONCLUSIONS: UR in females managed with medical treatments could be occurred occasionally. We think that thorough attentions are needed for UR to patients with cardiovascular disorders including diabetes mellitus, metastatic malignancy, chronic renal disorders urinary tract infection, and more careful interests when managing with drugs with antimuscarinic effects.

A new synthesis of carbon encapsulated Fe5C2 nanoparticles for high-temperature Fischer-Tropsch synthesis.

Using a simple thermal treatment under a CO flow, uniform micrometer-sized iron oxalate dihydrate cubes prepared by hydrothermal reaction were transformed into Fe5C2@C nanoparticles to form a mesoporous framework; the final structure was successfully applied to the high-temperature Fischer-Tropsch reaction and it showed high activity (CO conversion = 96%, FTY = 1.5 × 10(-4) molCO gFe(-1) s(-1)) and stability.

Balloon-occluded percutaneous transhepatic obliteration of isolated vesical varices causing gross hematuria.

Gross hematuria secondary to vesical varices is an unusual presentation. We report such a case recurrent gross hematuria in a male patient who had a history of bladder substitution with ileal segments that had been treated by balloon-occluded percutaneous transhepatic obliteration of vesical varices.

The Prostate Cancer Detection Rate on the Second Prostate Biopsy according to Prostate-Specific Antigen Trend.

PURPOSE: To identify the prostate cancer detection rate on the patients who had second prostate biopsy out of the patients who were reported negative in their first biopsy. MATERIALS AND METHODS: From July 2006 to February 2012, prostate biopsy was performed on 843 patients with over 4 ng/ml and on 618 biopsy negative patients PSA was performed from between 6 months and 9 months after biopsy. On 164 patients, second biopsy was performed, and 42 patients were selected. If there was less than 10% change between PSA before the prostate biopsy and PSA measured during 6 to 9 months after the first biopsy it was considered as no change. If above 10% increase, it was considered increase and if above 10% decrease it was considered as decrease. RESULTS: The cancer detection rate in PSA increase group was 20%, the detection rate in no change in PSA level but still over the normal range group 8.3%, and that in the PSA decrease group was 0%. When comparing prostate cancer group and non-cancer group, it is more probable to have prostate cancer when they are older, prostate volume is smaller and PSA density is higher. CONCLUSIONS: The second biopsy is strongly recommended when PSA level shows no change or increase, age is older, prostate volume is smaller or PSA density is higher.

Primary paratesticular osteosarcoma: A case report.

Extraosseous osteosarcoma originating from paratesticular soft tissue is an extremely rare type of malignant tumor. With the exception of the present study, only one other case of osteosarcoma originating from paratesticular soft tissue has previously been reported. A 52-year-old man presented with a painless scrotal swelling and palpable mass. The patient underwent left orchiectomy with the diagnosis of testicular tumor. Pathological examination was suggestive of osteosarcoma without any different histological components. The postoperative course of the patient was uneventful, and the patient is currently free of disease.

New iron-based mixed-polyanion cathodes for lithium and sodium rechargeable batteries: combined first principles calculations and experimental study.

New iron-based mixed-polyanion compounds Li(x)Na(4-x)Fe(3)(PO(4))(2)(P(2)O(7)) (x = 0-3) were synthesized, and their crystal structures were determined. The new compounds contained three-dimensional (3D)sodium/lithium paths supported by P(2)O(7) pillars in the crystal. First principles calculations identified the complex 3D paths with their activation barriers and revealed them as fast ionic conductors. The reversible electrode operation was found in both Li and Na cells with capacities of one-electron reaction per Fe atom, 140 and 129 mAh g(-1), respectively. The redox potential of each phase was ∼3.4 V (vs Li) for the Li-ion cell and ∼3.2 V (vs Na) for the Na-ion cell. The properties of high power, small volume change, and high thermal stability were also recognized, presenting this new compound as a potential competitor to other iron-based electrodes such as Li(2)FeP(2)O(7), Li(2)FePO(4)F, and LiFePO(4).

Male genital tuberculosis: epidemiology and diagnostic.

INTRODUCTION: Urogenital TB (UGTB) is the second most common form of extrapulmonary TB (EPTB) in countries with severe epidemic situation and the third most common form in regions with low incidence of TB. Male genital TB (MGTB) seems to be a rare disease. Nevertheless, 77% of men who died from TB of all localizations had prostate TB that had mostly been overlooked during their life time. MATERIALS AND METHODS: A Medline/PubMed research with key words "male genital tuberculosis" was conducted. Estimates of incidence and spectrum of EPTB in Siberia are presented on the basis of statistical reports for 1999-2010. Additionally, the clinical features and laboratory findings of 310 patients with UGTB are reported. RESULTS: A Medline/PubMed research with key words "male genital tuberculosis" resulted in a total of 861 titles only. During the last decade, the incidence rate of TB in Siberia increased up to 20%. Every year in Siberia, there are about 1000 new EPTB patients; the proportion of UGTB decreased from 42.9 to 33.9%. Late diagnosed complicated forms predominated. CONCLUSION: In Siberia, there is still a severe epidemic situation now. Low living standard, poverty, as well as poor knowledge lead to late diagnosis of EPTB with complicated multi-organ forms.

Effect of proton irradiation on the magnetic properties of manganese ferrite.

Cubic-spinel MnFe2O4 magnetic nanoparticles (NPs) were prepared, with an average particle size of about 4 nm determined from a high-resolution transmission electron microscope. When the NPs were proton-irradiated, the lattice constants decreased with increasing proton irradiation. Before the proton irradiation, the NPs exhibited 36.2 +/- 0.1 emu/g magnetization (M(S)) and 11.1 +/- 0.1 Oe coercivity (H(C)). After the irradiation of the samples with 5 and 10 pC/microm2 doses, the M(S) changed to 35.6 and 35.1 +/- 0.1 emu/g, and the H(C) to 11.3 and 12.9 +/- 0.1 Oe, respectively. The room-temperature Mössbauer spectra of the NPs showed superparamagnetic characteristics, with the single-absorption line of two sites and a large relaxation frequency. During the proton irradiation, the relaxation frequency decreased to 156.02 and 134.29 +/- 0.01 Gamma/h from the unirradiated sample's 164.02 +/- 0.01 Gamma/h. It is suggested that the proton irradiation induced the increase in the anisotropy energy of the MnFe2O4 NPs. Moreover, from the external-field-induced Mössbauer spectra at 4.2 K, an increase in the canted angle of the hyperfine field between sites A (tetrahedral) and B (octahedral) was observed with proton irradiation.

Pressure-dependent dissipation effect at multiple cantilever resonant modes.

Based on the optical deflection method, the resonant characteristics of a microcantilever under various pressure have been observed at room temperature to understand the pressure-dependent dissipation effect. Especially, the quality factor of the cantilever has been measured for up to fourth harmonic mode of cantilever resonance as a function of pressure between 0.1 and 1000 Torr. By considering the intrinsic dissipation present in the system at 0.1 Torr, the pressure-dependent fluidic quality factors were determined for the multiple cantilever resonant modes. The inverse of the fluidic quality factor appears to follow two different asymptotic behaviors at high and low pressure limits, which indicates that the dynamics of the fluid, due to the oscillating cantilever, changes from Newtonian to non-Newtonian with decreasing pressure. The experimentally observed transition of the fluidic dissipation effect agrees well with the recently proposed rapidly oscillating flow model based on the Boltzmann equation, regardless of the different mode shapes.