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•PBK models have helped to facilitate quantitative in vitroto in vivoextrapolation.•PBK modelling has the potential to play a significant role in reducing animal testing.•It is critical to assess the validity of PBK models built using non-animal data.•A framework is needed for communicating characteristics and results of PBK modelling.

This paper describes a systematic study for optimization of the multi-turn injection effciency of carbon-ions for medical synchrotron. This is accomplished by optimizing tunes, bump-magnet parameters, and the number of turns required for injection. For selecting optimal tunes, a frequency map is investigated which reveals various resonances limiting the injection efficiency. The injection bump and the number of turns are optimized by tracking numerous particles up to a few thousand turns after injection. Space-charge effects are considered and found to be non-negligible at the chosen injection energy, 7 MeV/u.

In this paper, we describe a research to minimize the three-dimensional (3D) emittance growth (EG) in the RAON accelerator, a heavy ion accelerator currently being developed in Korea to produce various rare isotopes. The emittance minimization is performed using the multi-objective genetic algorithm and the simplex method. We use them to analyze the driver linac for the in-flight fragmentation separator of the RAON facility and show that redesign of the 90-degree bending section of the RAON accelerator together with adjustment of optics in the upstream and downstream superconducting linacs can limit the 3D EG to ~20 % in the entire region of the driver linac. Effects of various magnet and rf accelerating cavity errors on the beam-EG are also discussed.

Patellofemoral pain syndrome (PFPS) is one of the most common causes of anterior knee pain in active populations. Due to its multifactorial nature, patellofemoral pain is hard to diagnose and treat. Increased stress in the subchondral bone is associated with PFPS and is correlated to elevated bone remodelling. [18F]NaF PET-MR imaging can localize regions of elevated bone remodelling and provide information about the metabolic processes involved (1, 2). Further, [18F]NaF uptake changes after exercise, thus showing that it is sensitive to changes in bone physiology resulting from acute bone loading (3, 4). For cartilage, T2 relaxation times have been used to study cartilage hydration and microstructure changes after exercise. While some studies have observed a decrease in T2 times after exercise, changes are usually transient and have largely been evaluated in the context of healthy subjects (5). An early sign of persistent abnormal mechanical stress is Bone Marrow Lesions (BMLs), which are strongly associated with pain and structural disease progression. We aimed to reproduce prior work which has shown that acute loading results in a large physiological response in bone regions with BMLs. Further, we wanted to explore if there is breakdown of the cartilage microstructure, either at baseline or in response to loading in cartilage regions adjacent to BMLs. The purpose of this study is to detect changes in the functional response of the knee joint to loading using [18F]NaF PET-MR imaging after a stair-climbing exercise in subjects with unilateral patellofemoral pain.

Conventional knee MRI protocols use numerous 2D FSE sequences with multiple contrasts, often repeated in multiple scan planes. This approach requires long scan times and does not fully utilize modern reconstruction, 3D, acceleration, and improved coil SNR technologies. Numerous approaches have been proposed to improve the value of knee imaging by reducing protocol times to less than 6 minutes and perhaps adding utility through quantitative data or oblique reformats. In this abstract, we present preliminary data and outline four such approaches: (1) an accelerated conventional 2D protocol; (2) a SNR-efficient 3D qDESS protocol, (3) a CUBE protocol, and (4) a thin-slice protocol with high resolution and compare them to a standard knee protocol.

This paper describes beam-optics design of a gantry for carbon ions in cancer therapy accelerators. A compact design is important for such a gantry. The designed gantry is compact such that its size is comparable to the size of the existing proton gantries. This is made possible by introducing superconducting double helical coils for dipole magnets. The gantry optics is designed in such a way that it provides rotation-invariant optics, a variable beam size, and point-to-parallel scanning of a beam. For large-aperture magnet, a three-dimensional magnetic field distribution is obtained by invoking a computer code, and a number of particles are tracked by integrating equations of motion numerically together with a three-dimensional interpolation. The beam-shape distortion due to the fringe field is reduced to an acceptable level by optimizing the coil windings with the help of a genetic algorithm. Higher-order transfer coefficients are calculated and shown to be reduced greatly with appropriate optimization of the coil windings.

We present a method for optimizing the multi-turn injection efficiency for a medical synchrotron. We show that for a given injection energy, the injection efficiency can be greatly enhanced by choosing transverse tunes appropriately and by optimizing the injection bump and the number of turns required for beam injection. We verify our study by applying the method to the Korea Heavy Ion Medical Accelerator (KHIMA) synchrotron which is currently being built at the campus of Dongnam Institute of Radiological and Medical Sciences (DIRAMS) in Busan, Korea. First the frequency map analysis was performed with the help of the ELEGANT and the ACCSIM codes. The tunes that yielded good injection efficiency were then selected. With these tunes, the injection bump and the number of turns required for injection were then optimized by tracking a number of particles for up to one thousand turns after injection, beyond which no further beam loss occurred. Results for the optimization of the injection efficiency for proton ions are presented.

Cellulose-calcium silicate (CCS) nanocomposites were fabricated through an environment-friendly process from waste wood, glass, and clam shells. Effect of heat-treatment on synthesis of CCS nanocomposites was investigated in terms of the precursor ratio and firing temperature. The optimization of cellulose, silicon, and calcium ratio resulted in the low temperature synthesis and also reducing input energy and the production of toxic by-products. The synthesized CCS nanocomposites were examined for its versatility, especially regarding its ability to replace plastics. The resulting biodegradable material has the potential for use in a variety of applications, including reducing CO2emissions.

The purpose of this study was to evaluate the dosimetric benefit of magnetic resonance imaging (MRI)-based dose adaptation in intracavitary brachytherapy (ICR) for cervical cancer. Dose-volume histograms were compared between matched conventional and optimized plans in 22 patients who were treated by MRI-based ICR. Doses to organs-at-risk (OAR) and dose covering 90% of high-risk clinical target volume (HR-CTV) were evaluated to compare OAR sparing and target coverage, respectively. The probability of RTOG rectal toxicity grade of =2 in the 22 patients was estimated based on the prediction model generated from previous three-dimensional CT-based ICR data. After optimization, doses to OAR showed a statistically significant decrease. The reduction percentage (reduced dose by optimization × 100/dose in the conventional plan) was higher in patients with HR-CTV >20 cc than in patients with HR-CTV =20 cc in the rectum. In patients with HR-CTV =20 cc, the mean probability of RTOG rectal toxicity grade =2 was 67.6% for the conventional plan and 47.8% for the optimized plan, based on the prediction model. In conclusion, dose adaptation by MRI-based ICR for cervical cancer resulted in significant dose reduction to the rectum, especially in patients with HR-CTV =20 cc.

We show that a femto-second hard X-ray radiation pulse can be generated in a free-electron laser amplifier without magnetic bunch compressors. This is possible by adopting a very low charge electron beam followed by the velocity bunching (VB) in two accelerating sections in a linear accelerator. With VB, an electron bunch with a bunch charge of 10 pC can be successfully compressed in the presence of the space-charge effect by a factor of 150, from 0.2 ps to 1.3 fs rms. Multi-gigawatt hard X-ray radiation can be generated from a 5-GeV electron beam, saturating in approximately a 40-m distance from the undulator entrance. Various accelerator and electron-beam parameters were optimized using a multi-objective genetic algorithm.

LOCO (Linear Optics from Closed Orbit) is a tool to analyze linear beam-optics and search for errors in the quadrupole focusing strength. Analysis with the help of LOCO reveals these errors by fitting the measured orbit-response matrix to the model orbit-response matrix. By readjusting the currents of the quadrupole-magnet power supplies to eliminate the magnet-gradient error, we can bring the machine’s optics parameter close to the design values. In this paper, we use LOCO to show how the design beam optics is restored in the PLS-II storage ring.

Ischemia/reperfusion injury and delayed graft function (DGF) following organ transplantation adversely affect graft function and survival. A large animal model has not been characterized. We developed a pig kidney allograft model of DGF and evaluated the cytoprotective effects of inhaled carbon monoxide (CO). We demonstrate that donor warm ischemia time is a critical determinant of DGF as evidenced by a transient (4–6 days) increase in serum creatinine and blood urea nitrogen following transplantation before returning to baseline. CO administered to recipients intraoperatively for 1 h restored kidney function more rapidly versus air‐treated controls. CO reduced acute tubular necrosis, apoptosis, tissue factor expression and P‐selectin expression and enhanced proliferative repair as measured by phosphorylation of retinol binding protein and histone H3. Gene microarray analyses with confirmatory PCR of biopsy specimens showed that CO blocked proinflammatory gene expression of MCP‐1 and heat shock proteins. In vitroin pig renal epithelial cells, CO blocks anoxia‐reoxygenation‐induced cell death while promoting proliferation. This large animal model of DGF can be utilized for testing therapeutic strategies to reduce or prevent DGF in humans. The efficacy of CO on improving graft function posttransplant validates the model and offers a potentially important therapeutic strategy to improve transplant outcomes.

A non-linear dynamic model of the common-rail direct-injection (CRDI) diesel engine was proposed and verified through engine tests. Typical engine models used in control applications do not compute the pressure within the cylinder. This is, however, not ideal for cases when the model needs to be run over a wide range of operating conditions, or if the controller uses the cylinder pressure itself as a measured variable. The developed engine model includes in-cylinder pressure dynamics as the heart of the cylinder-by-cylinder engine model (CCEM). The inclusion of cylinder pressure dynamics makes it possible to reflect precisely the influence of the changes in inputs, and thus the applicable operating range of the engine model is expanded. Moreover, a cylinder-pressure-based control algorithm can be developed and easily evaluated on this model. Based on the CCEM, a distributed electronic-control-unit-in-the-loop simulation platform was developed for the CRDI diesel engine.

Trigeminal neuralgia (TN) usually leads to paroxysms of short lasting but very severe pain. Between the attacks the patient is usually asymptomatic, but a constant dull background pain may persist in some cases. The mechanisms associated with the development of this chronic pain are not well understood.

New spherical nanostructures of titania (TiO2) have been synthesized through formation of liposome−TiO2 nanocomposites by using egg lecithin lipid as a template, and their optical properties have been investigated with regard to the dynamics of surface charge carriers and photocatalytic activities by using UV−vis and photoluminescence (PL) spectroscopic techniques. On the basis of the measurements of X-ray diffraction, transmission electron microscopy, and atomic force microscopy, the spherical titania nanostructures are identified to be anatase crystalline nanodisks with an average diameter of 9 nm and height of 0.5 nm. The nanodisks have a large Brunauer−Emmett−Teller specific surface area of 227 m²/g. The FT-IR and X-ray photoemission spectra of the nanodisks confirm that the skeleton structure of the titania nanodisk is formed through H-bonding of the −Ti−O−Ti− network through tetrahedrally coordinated vacancies designated 4Ti⁴⁺−OH. Analysis of the UV−vis and PL spectra reveals that the band-gap energy is red-shifted to 3.02 eV from that of TiO2 nanoparticle dots and its transition nature is exclusively indirect. The PL emission spectrum of the titania nanodisks exhibits a strong structural emission band around 420 nm with shoulders around 470 and 550 nm which is attributed to the transition from three different exciton-trapped surface states. In addition, another surface emission originating from the coordinatively unsaturated ions (Ti³⁺) is observed at 618 nm. These results suggest that coupling of the surface charge carriers with the lattice phonon of the nanostructures is so strong that the dominant route to charge recombination in titania nanodisks is nonradiative. Supporting the steady-state spectral observations, the decay profiles of the surface emission measured by using a femtosecond laser time-resolved PL system fit into a triexponential function with relatively longer lifetimes (20−30 ps, 1.1−1.5 ns, and 4.5−6.0 ns) as compared to those of simple nanoparticle dots, indicating that recombination of the charge carriers on the nanodisk surface is very prolonged. Being consistent with this, the photocatalytic efficiency for the reduction of methyl orange is much higher in the presence of the titania nanodisks than that observed in the presence of Degussa P-25.

Migraine headache is a chronic, painful, disabling and potentially progressive, condition primarily occurring in early and middle adulthood. For many patients, daily activities are impaired by the sudden and unpredictable occurrence of migraine attacks. In recent years, significant progress has been made in the field of migraine treatment. For the acute treatment of migraine attacks, 5-hydroxytryptophan1B/Dagonists (so called triptans), were the most innovative development, successfully aborting attacks in less than 1 h. The search for innovative drugs usable for migraine prevention, however, was less successful, mainly due to the lack of reliable and predictive animal models. Recently, neuromodulators such as valproic acid and topiramate, initially developed as anticonvulsants, have been shown in large clinical trials to be effective in the prevention of migraine. As for the acute treatment of migraine attacks more than 10 years ago, large clinical trial programs are now setting new standards for evidence-based medicine in migraine prevention. This review summarizes the current options in migraine prevention with special emphasis on clinical trial design and new developments such as topiramate.

A new series of mixed phenylene−thiophene oligomers with terminal n-perfluorooctyl groups has been synthesized. These compounds are 2,5-bis(4-n-perfluorooctylphenyl)thiophene (DFO−PTP, 1), 5,5‘-bis(4-n-perfluorooctylphenyl)-2,2‘-bithiophene (DFO−PTTP, 2), 5,5‘ ‘-bis(4-n-perfluorooctylphenyl)-2,2‘:5‘,2‘ ‘-terthiophene (DFO−PT3P, 3), 5,5‘ ‘‘-bis(4-n-perfluorooctylphenyl)-2,2‘:5‘,2‘ ‘:5‘ ‘,2‘ ‘‘-quaterthiophene (DFO−PT4P, 4), and 1,4-bis[5-(4-n-perfluorooctylphenyl)-2-thienyl]benzene (DH−PTPTP, 5). These systems have been characterized by ¹H and ¹⁹F NMR, elemental analysis or HRMS, optical absorption and emission spectroscopies, differential scanning calorimetry, and thermogravimetric analysis. Vacuum-deposited films were characterized by optical absorption and emission spectroscopy, X-ray diffraction, scanning electron microscopy, and field effect transistor measurements. As thin films, all of the fluorinated compounds are n-type semiconductors with carrier mobilities ranging from ~10^-6 to ~ 0.1 cm² V^-1 s^-1, depending on the substrate deposition temperature. Furthermore, these films exhibit very large current Ion:Ioff ratios (up to ~10⁷) due to substantially suppressed off-currents. Particularly interesting is straightforwardly synthesized DFO−PTTP (2), which displays a combination of high mobility, high current Ion:Ioff ratio, and reversible, tunable, and stable memory effects.

Background: We evaluated the imaging features of portal vein aneurysm occurring at the umbilical portion and the relation between portal vein aneurysm of the umbilical portion and portal vein anomaly. Methods: Retrograde analysis was performed in 18 patients with portal vein aneurysm of the umbilical portion of the portal vein. We analyzed the size, shape, and imaging findings of portal vein aneurysm. In addition, we evaluated associated portal vein anomalies, specifically, the branching pattern of the intrahepatic portal vein and the position of the umbilical portion of the left portal vein. Results: The diameter of the portal vein aneurysm ranged from 1.5 to 2.2 cm and the shape of the portal vein aneurysm was saccular (n = 14) or fusiform (n = 4). Imaging findings of the portal vein aneurysm of the umbilical portion were typical for its vascular nature. Portal vein anomalies were seen in eight of 18 patients (44%): the right anterior segmental portal vein (n = 7) or the right anterior and posterior segmental portal veins (n = 1) originating from the umbilical portion of the left portal vein and a rightward deviation of the umbilical portion of the left portal vein (n = 4). Conclusion: Due to its vascular nature, noninvasive diagnostic modalities can enable the detection of portal vein aneurysm of the umbilical portion, and there is a close relation between portal vein aneurysm of the umbilical portion and portal vein anomaly.

We have investigated the resonance Raman (RR) spectra of the directly linked porphyrin arrays in order to elucidate the relationship between excitonic interactions and molecular geometry depending on the number of pigments in the arrays. The RR spectra obtained by photoexcitation at the high-energy exciton Soret bands in the arrays are mainly composed of Raman modes localized on the constituent porphyrin monomers. In contrast, the RR spectra of the arrays with photoexcitation at the low-energy exciton split Soret bands reveal some characteristic Raman bands arising from strong excitonic interactions between the adjacent porphyrins in the arrays. Based on the RR measurements of the isotope labeled analogues and the normal-mode analysis of the dimer, it is suggested that the photoexcitation at the high-energy Soret band produces an electronically excited state largely localized within a monomer unit and that at the low-energy exciton split Soret band the excited state is in a way delocalized throughout the array. Normal mode calculation revealed that some of the RR bands of Z2 arise from vibrational splitting by dimeric interactions. Phonon-like behaviors were observed for some Cm−Cm stretching modes of the arrays, which is ascribed to enhanced polarizability induced by phenyl group movement. Collectively, our data from RR spectroscopic measurements as well as the normal-mode analysis provide a picture of the exciton coupling in relation to the molecular structure of the directly linked linear porphyrin arrays.

Brief myocardial ischaemia has been demonstrated to result in mechanical and coronary endothelial dysfunction, in which calcium may play a role. We examined whether the mechanical and vascular responses to calcium are altered in postischaemic, reperfused myocardium.

In this paper, we introduce an efficient three-dimensional magnetic field mapping system for a Deflection Yoke (DY) in Cathode-Ray Tube (CRT). A three-axis Hall probe mounted in a small cylindrical bar and three-stepping motors placed in a non-magnetic frame were utilized for the mapping. Prior to the mapping starts, the inner contour of DY was measured by a laser sensor to make a look-up table for inner shape of DY. Three-axis magnetic fields are then digitized by a three-dimensional Hall probe. The results of the mapping can be transformed into various output formats such as multipole harmonics of magnetic fields. Field shape in one, two and three- dimensional spaces can also be displayed. In this paper, we present the features of this mapping device and some analysis results.

5,10,15,20-Tetraphenyl-21H,23H-porphine manganese(III) chloride (Mn^IIITPP(Cl)) was encapsulated into MCM-41 and TiMCM-41, and its photoinduced electron transfer had been studied by using femtosecond diffuse reflectance photolysis. Two different transient species (c.a. 10 ps and c.a. 80 ps) were observed. The shorter-lived species should be originated from relaxation of a “tripmultiplet” state and the longer-lived species should be attributed to the spin-forbidden relaxation (slower than the spin-allowed decay of triptquintet) via a quintet CT state. After irradiation, MnTPPCl^+• radicals are detected in MCM-41 or TiMCM-41, indicating that the mesoporous silicate framework plays a good electron acceptor. Furthermore, it has been found that the formation MnTPPCl^+• is easier in TiMCM-41 than in MCM-41, indicating that framework modification by incorporating the Ti⁴⁺ into the MCM-41 enhances the electron-accepting ability of the MCM-41 framework.

The photoinduced energy transfer processes in 1,4-phenylene-, 1,3-phenylene, 1,2-phenylene, and 4,4‘-biphenylene-linked and directly-linked Zn(II)-free base porphyrin heterodimers in THF were investigated by femtosecond transient absorption spectroscopy. The energy transfer rates were compared between TPP-type and OEP-type heterodimers respectively as A2u-HOMO and A1u-HOMO subunits, for evaluating the relative contribution of the through-bond and through-space interactions. The rate difference becomes smaller with a decrease of spacer, more than 10 for 1,4-bis(phenylethynyl)phenylene and 1,4-diphenylethynylene, 4 for 4,4‘-biphenylene-linked heterodimer, and 3 for 1,3- and 1,4-phenylene-linked spacers. In the meso−meso directly-linked case, the energy transfer rates are the same ((0.55 ps)^-1) for 5,5,15,15-tetrakis(3,5-bis(octyloxy)phenyl)-substituted and 5,5,15,15-tetrakis(pentafluorophenyl)-substituted heterodimers, featuring only a minor influence of the frontier orbital characteristics on the energy transfer rate. The energy transfer rates are identical (0.55 ps)^-1 for the directly-linked meso−meso heterodimers substituted with 3,5-bis(octyloxy)phenyl and pentafluorophenyl groups regardless of the difference in the HOMO orbital symmetry characteristics, suggesting the predominant Coulombic interaction for the energy transfer in these close proximity porphyrin dimers. In the case of 1,2-phenylene-linked heterodimers, the choice of the peripheral substituents can lead to a state-to-state rapid energy transfer with a rate of (0.55 ps^-1) for the TPP-type model or a delocalized excimer-like diporphyrin excited state for the OEP-type model. Collectively, these results indicate that even for the covalently-linked models the relative contribution of the through-space Coulombic interaction becomes increasingly important upon the decrease of the center-to-center separation. Especially, the fast and efficient energy transfer occurring in the directly-linked heterodimer illustrates that this porphyrin unit can be utilized as a good candidate for energy transfer functional arrays in molecular photonic devices.

TiO2 colloids are very useful photocatalytic systems, capable of converting solar energy to chemical or electrical energy and environmental cleaning. The key step in enhancing photocatalytic efficiency is improving photoinduced interfacial electron transfer like plant photosynthesis. It remains difficult to modify TiO2 particles as a real analogue of the photosynthetic reaction centers of green plants. We attempted to incorporate a photoreactive heteropoly acid (HPA) such as H3PW12O40 into TiO2 colloids in aqueous polyvinyl alcohol (PVA) (0.1%) solution, and found that two light reactions appear to operate in a series. Upon illumination of the HPA/TiO2 system with near-UV light (300−375 nm), interfacial electron transfer takes place from the conduction band of TiO2 to the incorporated HPA, which is also excited to catalyze photoreduction of Methyl Orange. The extent of the photoinduced reduction of the HPA adsorbed on TiO2 particles depends on the concentration ratio of the HPA and TiO2 colloids, irradiation wavelength, and intensity of radiation. It is found that the interfacial electron-transfer mechanism of HPA/TiO2 is quite analogous to the “Z-scheme” mechanism for plant photosynthetic systems. The photoinduced charge-carrier generation at the heterojunction is very efficient, and the photoreduction of Methyl Orange has been observed to be synergistically enhanced upon illumination of the HPA-incorporated TiO2 with visible light as well as near-UV light.

One hypothesis of the pathophysiology of pre-eclampsia is that placentally derived, yet unidentified, vasoactive factors are released into the maternal circulation, causing hypertension.

Abstract: Background: The aim of this study was to determine the imaging characteristics of presacral epidermoid cysts and correlate the imaging findings with the histopathologic findings. Methods: We retrospectively reviewed sonographic, computed tomographic, and magnetic resonance examinations in four consecutive patients with a pathologically proven presacral epidermoid cyst. Imaging findings of the presacral epidermoid cyst were correlated with the histopathologic findings. Results: In all four patients, sonography showed a presacral mass with a heterogeneous low echogenicity, and computed tomography showed a discrete well-defined hypodense presacral mass with a thin wall. In the three patients who underwent magnetic resonance imaging, the mass showed a heterogeneous low signal intensity on the T1-weighted image and a high signal intensity with multiple small foci of low signal intensity in the nondependent portion of the mass on the T2-weighted image. These imaging findings correlated well with the pathologic results. Aggregates of keratinous material contributed to these imaging findings. Conclusion: In the diagnosis of the presacral epidermoid cyst, sonographic and magnetic resonance imaging findings may be helpful.

Fluorescence and mass-resolved S1−S0 excitation spectra of p-methoxybenzyl alcohol in a supersonic jet are reported. The long vibrational progression bands are observed in both spectra and attributed to the modes involving torsional motion of the CH2OH moiety with respect to the rest of the molecule. The spectral origin for the S1−S0 transition is found to be at 35 701 cm^-1. Two additional distinct vibrational progression bands are observed with their pseudo origins at 35 785 and 35 863 cm^-1 . Fluorescence depletion spectroscopy shows that these three vibrational progression bands are originated not from three different conformers but from single conformer in the jet. The torsional barrier height of 316 cm^-1 in the S1 ground-vibrational state is obtained from the comparison of the experiment with the calculation assuming a sinusoidal function for the potential energy surface along the torsional angle. The comparison of the relative intensity distributions in the vibrational progression bands with the calculation of Franck−Condon factors using a free-rotor basis set suggests that the molecular geometry at the minimum energy of the S1 state is around 45° rotated about the CH3OC6H4---CH2OH axis compared to that of the S0 state.

Abstract: Background: The aim of this study was to determine the color Doppler features of tuberculous epididymitis and to correlate these findings with histopathologic findings. Methods: Color Doppler ultrasound (US) findings of 12 histopathologically proven tuberculous epididymitis and tuberculous epididymo-orchitis in 11 consecutive patients were retrospectively analyzed. Color Doppler US findings of tuberculous epididymitis were correlated with histopathologic findings. Results: Color Doppler US findings of tuberculous epididymitis demonstrated no blood flow in the epididymal lesions except for focal linear or spotty flow signals in the peripheral portion. These findings correlated well with pathologic findings; the central portion of the epididymal lesions demonstrated granulomas with caseation necrosis, and the peripheral portion of the epididymal lesions had several medium to small vessels. Conclusions: Color Doppler US may be helpful for differential diagnosis of tuberculous epididymitis and non–tuberculous epididymitis.

The axial ligand photodissociation processes of halochromium(III) tetraphenylporphyrin (XCr^IIITPP, X = Cl, Br) have been investigated in noncoordinating and coordinating solvents by transient Raman and absorption spectroscopic techniques. In noncoordinating solvents such as benzene, the upshift of the ν2 and ν4 bands and the disappearance of Cr&sbd;X stretching mode in the transient Raman spectra demonstrate the core size reduction of the porphyrin macrocycle accompanied by the photodissociation of axial halogen ligand atoms in the excited state. In coordinating solvents such as tetrahydrofuran (THF), where the solvent molecule is already attached to XCr^IIITPP as an axial ligand to form XCr^IIITPP(THF), the transient spectroscopic data indicate that the axial halogen ligand atoms photodissociate to form the five-coordinate Cr^IIITPP(THF) on photoexcitation. The temporal evolutions of photoinduced absorption and bleaching signals of XCr^IIITPP in benzene exhibit biphasic decay profiles with time constants of 1 and 20 ms. The shorter decay is likely due to the four-coordinate photoexcited Cr^IIITPP* species, and the relatively slow decay component seems to be the recombination process returning to the original five-coordinate XCr^IIITPP species. On the other hand, a significant reduction in the lifetime of photoexcited ClCr^IIITPP in THF was observed as compared with that in benzene. This behavior seems to be caused by the excited five-coordinate Cr^IIITPP(THF)* species, which decays rapidly with a time constant of 632 ps due to the participation of low-energy states in the deactivation process below the normally emissive tripmultiplet (π,π*) states. The electronic nature of the lowest excited state of the five-coordinate Cr^IIITPP(THF)* species is suggested to possess (π,dπ) charge transfer character based on the comparison of transient Raman and absorption spectral features with those of other paramagnetic metalloporphyrins. We explain the axial ligand photodissociation processes in terms of the electron density change in metal d orbitals, which is particularly sensitive to the interaction with σ-donor axial ligands.