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Low-voltage operation, high durability, and long memory time are demanded for electrochromic (EC) display device applications. Metallo-supramolecular polymers (MSPs), composed of a metal ion and ditopic ligand, are one of the recently developed EC materials, and the ligand modification is expected to tune the redox potential of MSP. In order to lower the redox potential of MSP, tetrakis(N-methylbenzimidazolyl)bipyridine (LBip) was designed as an electronically rich ligand. Ru-based MSP (polyRu-LBip) was successfully synthesized by 1:1 complexation of RuCl2(DMSO)4 with LBip. The molecular weight (Mw) was high (8.8 × 106 Da) enough to provide a simple 1H NMR spectrum, of which the proton peaks could be assigned by the comparison with the spectrum of the corresponding mono-Ru complex. The redox potential (E1/2) between Ru(II/III) was 0.51 V versus Ag/Ag+, which was much lower than the redox potential of previously reported Ru-based MSP with bis(terpyridyl)benzene (0.95 V vs Ag/Ag+). The polymer film exhibited reversible, distinct color changes between violet and light green-yellow upon applying very low potentials of 0 and 0.6 V vs Ag/Ag+, respectively. The appearance and disappearance of the metal-to-ligand charge transfer absorption by the electrochemical redox between Ru(II/III) were confirmed using in situ spectro-electrochemical measurement. A solid-state EC device with polyRu-LBip was revealed to have large optical contrast (ΔT 54%), fast response time (1.37 s for bleaching and 0.67 s for coloration), remarkable coloration efficiency (571 cm2/C), and high durability for the repeated color changes more than 20,000 cycles. The device also showed a long optical memory time of up to 19 h to maintain 40% to the initial contrast under the open circuit conditions. It is considered that the stabilization of the Ru(III) state by LBip suppressed the self-coloring to Ru(II) inside the device.

For the development of durable electrochromic (EC) materials with wide absorption, large optical contrast, and high coloration efficiency, a three-dimensionally hyperbranched Fe(II)-based metallo-s...

Dual-redox metallo-supramolecular polymers with a zigzag structure (polyFe-N and polyRu-N) were successfully synthesized by 1:1 complexation of a redox-active Fe(II) or Ru(II) ion and 4,4-bis(2,2:6,2-terpyridinyl)phenyl-triphenylamine (LTPA) as a redox-active ligand. The polymers had high solubility in methanol, and the polymer solutions showed dark brown (polyFe-N) or orange-red (polyRu-N) coloration. UV-vis spectra of the polymers displayed a strong metal-to-ligand charge transfer (MLCT) absorption in the visible region. Cyclic voltammograms of the polymer films exhibited two pairs of reversible redox waves. The first redox at ∼0.5 V versus Ag/Ag+ was assigned to the redox in the triphenylamine (TPA) moiety of LTPA, and the second redox at 0.8 V versus Ag/Ag+ (polyFe-N) or 0.9 V versus Ag/Ag+ (polyRu-N) was given to the redox of Fe(II)/(III) or Ru(II)/(III), respectively. Upon applying a positive potential of more than 0.5 V versus Ag/Ag+ to the polymer films, a new absorption at ∼820 nm in the near-infrared (NIR) region appeared with wide tailing to the longer wavelength. It is considered that the new absorption in the NIR region is caused by the polaron band of the oxidized ligand in the polymers. When the applied potential was increased to 1.0 V versus Ag/Ag+ (polyFe-N) or 1.1 V versus Ag/Ag+ (polyRu-N), the maximum wavelength of the new absorption in the NIR region shifted to 885-900 nm and the absorbance was further enhanced with disappearance of the MLCT absorption. Eventually, the original colors of the polymers were faint to light green. This visible-to-NIR electrochromism was reversible, and maximum optical contrast (ΔT) reached 52% in the visible region and 80% in the NIR region. A prototype solid-state device with the polymer was fabricated for practical utilization, exhibiting excellent cycle stability of >4000 cycles with maintaining high optical contrast from the visible-to-NIR range.

A durable supercapattery film was fabricated by a combination of dual-branched dense hexagonal Fe(II)-based coordinated nanosheets (polyFe-2D) and Fe-hexacyanoferrate. The complementary redox prope...

Metallo-supramolecular polymer (MSP)-based electrochromic devices (ECDs) have drawn much attention because of their variable colors and attractive electrochromic (EC) properties. However, fabrication of voltage-tunable multicolor ECDs using single MSP is yet hard to realize. We anticipated alternate introduction of two different redox-active metal ions in an MSP combined with the adjustment of counteranions could be a solution to fabricate multicolor ECDs. The heterometals will induce color variability upon voltage alteration, and counteranions will help to tune the solubility of MSP in different solvents. In an attempt to fulfill this target, we have synthesized four heterobimetallic supramolecular polymers (HBPs) having different counteranions (BF4-, Cl-, PF6-, and OAc-), in which Fe(II) and Os(II) are alternately complexed by two terpyridine units. To apply as EC material, the HBPs should be soluble in methanol and insoluble in acetonitrile for the preparation of EC film as well as ECDs. However, among the HBPs, only HBP-OAc is found to meet this requirement. The EC behaviors of the spray-coating film of HBP-OAc on an indium tin oxide (ITO)-coated glass substrate are investigated in terms of maximum transmittance contrast, coloration voltage, response time, coloration efficiency, and operational stability, which exhibits reversible multicolor electrochromism (the initial purple color of the film is changed to violet followed by greenish-yellow) upon alteration of the voltage from 0.0 to 0.7 V [required to oxidize the Os(II) ion] and to 1.0 V [required to oxidize the Fe(II) ion]. The film is also integrated into a laminated ECD by using lithium-based gel electrolyte. Finally, as a proof-of-concept, a prototype voltage-tunable multicolor EC display (6 cm × 2.5 cm) is fabricated by using a designed image containing a flower, leaves, and a flower pot, which exhibits six different types of multicolor image upon application of tunable voltages.

We synthesized Fe(II)-based metallo-supramolecular polymers with bisterpyridines bearing ethynylene, phenylene, and durene as spacer (polyFeL1–3) and investigated the effect of the spacer modificat...

A heterobimetallic supramolecular polymer (polyRuFe) with alternately complexed Ru(II) and Fe(II) is prepared following a stepwise synthetic route through harnessing first the strongly binding metal ion Ru(II) and then the weakly binding metal ion Fe(II). A high yield of product is achieved in each step. The heterometal ions are incorporated into the polymer chain in identical coordination environments formed by two 2,2′:6′,2″-terpyridine moieties. Characterization is accomplished by NMR spectroscopy, MALDI–TOF mass spectrometry, UV–Vis spectroscopy, and cyclic voltammetry. PolyRuFe shows a wide optical window (λ = 311–577 nm) and a broad distinct reversible redox nature of two types, originated from the coupling of the two heterometallic segments into the polymer chain. Such characteristics of polyRuFe suggest its potential for various electrochemical and electro-optical applications.

Highly dense hexagonal Fe(II)-based coordination nanosheets (CONASHs) were designed by dual-branching, at the metal-coordination moieties and the tritopic ligands, which successfully obtained a liquid/liquid interface by the complexation of Fe(II) ions and the tritopic bidentate ligands. The 1:1 complexation was confirmed by titration. The obtained Fe(II)-based nanosheets were fully characterized by small-angle X-ray scattering (SAXS), atomic force microscopy (AFM), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray photoelectron spectroscopy (XPS). A monolayer of the sheets was obtained, employing the Langmuir-Blodgett (LB) method, and the determined thickness was ∼2.5 nm. The polymer nanosheets exhibited red-to-colorless electrochromism because the electrochemical redox transformation between Fe(II) and Fe (III) ions controlled the appearance/disappearance of the metal (ion)-to-ligand charge-transfer (MLCT) absorption. The poor π-conjugation in the tritopic ligands contributed to the highly colorless electrochromic state. A solid-state device, with the robust polymer film, exhibited excellent electrochromic (EC) properties, with high optical contrast (Δ

Four color electrochromism (yellow, magenta, blue, and navy) has been achieved in Cr(III)-based metallo-supramolecular polymers (polyCr), which were synthesized by 1 : 1 complexation of Cr ions and 1,4-di[[2,2′:6′,2′′-terpyridin]-4′-yl]benzene (L). The polymer structure was determined by X-ray absorption fine structure (XAFS) measurement and X-ray photoelectron spectroscopy (XPS). The molecular weight of polyCr was calculated as 3.2 × 107 Da using right angle light scattering (RALS). The EXAFS fitting indicated that the bond distances of Cr–N are 2.020 A and 2.208 A. A film of polyCr shows multi-color electrochromism (EC) or absorption: a sharp peak at 380 nm at 0 V vs. Ag/Ag+ (yellow), a sharp peak at 510 nm and a broad peak at 800 nm at −0.6 V vs. Ag/Ag+ (magenta), a broad peak at 610 nm and between 700–900 nm at −1.2 V vs. Ag/Ag+ (blue), a broad peak between 450–900 nm at −1.8 V vs. Ag/Ag+ (navy). The transmittances change (ΔT), the switching times for coloring and bleaching (Tc, Tb) and the coloration efficiency (ηc, ηb): [ΔT, (Tc, Tb), (ηc, ηb)] were [39.2%, (5.56 s, 1.39 s), (169 cm2 C−1, 230 cm2 C−1)] at 510 nm between −0.6 and 0.2 V vs. Ag/Ag+, [67.0%, (6.93 s, 2.52 s), (138 cm2 C−1, 172 cm2 C−1)] at 610 nm between −1.2 and 0.2 V vs. Ag/Ag+, [86.1%, (6.80 s, 3.03 s), (167 cm2 C−1, 134 cm2 C−1)] at 780 nm between −1.8 and 0.2 V vs. Ag/Ag+, respectively, during the cycles. The durability experiment indicates that polyCr shows an EC property for at least 100 cycles.

A novel terpyridine-based bimetallic metallo-supramolecular polymer (polyFeOs) containing alternately complexed Fe(II) and Os(II) ions is synthesized. For precise synthesis of the polymer, a new three-step synthetic pathway is developed to obtain a high yield (%) of product in each step. The first step is the synthesis of dibromo terpyridine-Os(II) complex in 87% yield, the second step is the synthesis of bisterpyridine ligand containing Os(II) (OsL1) in 74% yield, and the last step is the synthesis of polyFeOs in 90% yield. The polyFeOs exhibits high thermal stability with two degradation temperatures at around 390 and 690 °C, which indicate thermal evaporation of the counter anions (Cl- and BF4 - ) and degradation of the coordination bonds, respectively. The combination of two different metal ions in polyFeOs results in an enlarged optical window (λ = 315-675 nm) and two highly stable reversible redox states, which can be of huge interest for potential optical, electro-optical, and electrochemical applications.

Developing high proton conducting solid materials is significant in the field of fuel cells. A europium(III)-based metallo-supramolecular polymer with uncoordinated carboxylic acids (PolyEu-H) was successfully synthesized by modifying the synthesis conditions. The proton conductivity was enhanced with increasing the relative humidity (RH) from 30 to 95% RH. PolyEu-H showed about 104 times higher proton conductivity than the polymer with coordinated carboxylic acids (PolyEu) and about 400 times higher than the polymer without carboxylic acids (PolyEu-2). The proton conductivity of PolyEu-H reached 4.45 × 10−2 S cm−1 at 95% RH and 25 °C and 5.6 × 10−2 S cm−1 at 75 °C. The activation energy, Ea was ultralow (0.04 eV), which indicates proton conduction based on the Grotthuss mechanism. The results indicate that efficient proton conduction occurs through proton channels formed by moisture in PolyEu-H.

An artificial allosteric system composed of a zinc porphyrin moiety as a ligand-binding site, diphenylanthracene moieties as sterically bulky shielding units, and bipyridine terminals as Fe(II) ion...

Zn–porphyrin with bipyridyl units at the ends of a conjugated chain, in addition to two alkyl side chains, was prepared as an artificial allosteric system. The axial ligand-binding ability of the compound was considerably reduced by the formation of a Fe(bpy) 3 -type complex. The degree of the allosteric suppression strongly depended on both alkyl chain length and the steric demand of the pyridyl ligand.

Previous reports demonstrated 8–60% patients treated for developmental dislocation of hip (DDH) in infancy have residual acetabular dysplasia (AD) at skeletal maturity. AD patients reportedly exhibit abnormal morphology of the pelvis, high rates of comorbid spinal congenital anomalies and high bone mineral density. These physical findings suggest that AD patients have genetic background. We examined the percentage of AD patients with hip pain at skeletal maturity having a history of DDH in infancy and the correlation between the severity of AD at skeletal maturity and history of DDH treatment to investigate the relationship between AD and DDH. A total of 245 patients were radiographically examined for any history of DDH treatment in infancy. The study included 226 women and 19 men with a mean age at examination of 40.7 years (range 17–59 years). Eighty-eight patients (36%) had a history of DDH treatment (DDH group) and the remaining 157 patients (64%) had no history of DDH treatment (non-DDH group). The average age was lower and acetabular angle was larger in the DDH group. There was a significant increasing trend of the percentage of DDH patients associated with the severity of AD classified with CE, acetabular angle, and acetabular roof angle. Our data suggest that there are several AD patients without a history of DDH in Japan, and AD in patients without a history of DDH has different characteristics from AD in patients with a history of DDH.

We report a 3-year-old girl with permanent dislocation of the patella due to distal femoral epiphyseolysis in the perinatal period.This distal femoral epiphyseolysis may have occurred from a trial of external cephalic version.Radiogram showed genu valgum in the right knee when aged two months.Presently, the patient has a permanent lateral dislocation of the patella.The etiology of patellar dislocation is discussed.

Congenital absence of the tibia is a rare congenital anomaly causing marked shortening of the involved extremity.A long-term case of congenital absence of the tibia is reported. A 13-year-old boy entered our hospital for correction of his ankle and foot deformity, and lower leg lengthening using the I lizarov method. His absence belonged to the Ib type according to Jones' clssification.At 1 year and 2 months he had Brown's procedure and at 3 years of age ankle arthrodesis had been performed with remarkable equinovarus. Roentgenologically we can observe that his fibula widered and lergthened compared to normal.

Eighteen supracondylar fractures of the femur in sixteen patients have been treated at out hospital since 1982. These fractures were divided into the following groups according to Sunami's classification IIA (1 fracture), IIB (1 fracture), III (4 fractures), IVA (2 fractures) and IVB(10 fractures). The average follow-up period was four years and two months.Clinical results were evaluated using Neer's criteria with excellent and satisfactory results obtained in 83.3%.Male patients were younger than females and the results were good irrespective of the fracture type. Ender's intramedullary nailing was indicated for supracondylar fractures because it keeps the surrounding soft tissue intact.Factors which were associated with unsatisfactory results were elderly osteoporotic conditions (particularly female patients), severe complications, and delay in ROM exercises.

We report on the usefulness of MRI in infectious bone and joint lesions, describing the MRI findings in the following three cases.Case 1: A 35-year old male with chronic osteomyelitis of the femur. MRI showed a clear border between the lesion and surrounding tissue.Case 2: A 13 year-old female who had acute arthritis of the ilio-sacral joint. The characteristic MRI finding was edematous change around the lesion, which imaged as low intensity in T1 but was high intensity in T2.Case 3: A 53-years-old male with tuberculous osleoarthritis of the shoulder. MRI was useful in diagnosing the site of the gravity abscess.

Hand and chest X-rays of 25 classic or definite rheumatoid arthritis patients were reviewed. The mean duration of follow-up was 4.8 years, with X-rays showing advancement of the RA stages over several years.In many cases joint destruction of the hand started at the carpal joint. Fourteen patients had signs of pulmonary disease on chest X-ray. On the basis of pulmonary function data, 5 of 23 patients were diagnosed as hawing restrictive disease, 1 patient had mixed restrictive and obstuctive disease, and 0 of 20 patients had reduced diffusing capacity.

The authors have reported on orthopaedic diseases associated with chronic renal faiiure treated with hemodialysis at Sasebo General Hospital for the last five years. The subjects were 16 cases of 14 patients, 9 cases were fractures, 2 were ruptures of the quadriceps tendon, 2 were tumoral calcinosis, and 3 cases were carpal tunnel syndrome.Surgical treatment was applied in 13 cases, the rest were treated conservatively. Infection, mental disturbance, and hypovolemic shock were recognized as postoperative complications in the fracture group.

This report is a follow up study of surgically treated patello-femoral joint disorders of 20 knees (4 acute dislocations, 4 recurrent dislocations, 9 subluxations, 2 congenital dislocations and one habitual dislocation) in 18 patients. The age of patients ranged from 5 to 32 years (mean: 16.5 years) and the average duration of follow-up was 3 years and 5 months.All knees underwent an operation consisting of medial plication and lateral releases. Sixteen knees had surgery performed in the manner of tibial tubercle plasty with medial advancement.Clinical results, evaluated according to Cox's criteria were as follows: exellent in 11 knees (55%); good in 7 knees (35%); and fair in 2 knees (10%).The tilting angle and the lateral shift of the patella in their skyline view were distinctly improved.

Asphyxiating thoracic dystrophy (ATD) was first described by Jeune et al in 1954. The main features are a narrow, constricted rib cage and generalized chondrodystrophy with shortlimbed dwarfism. A case of ATD is reported. A boy was 4years 9month old. He had a episode of cardiorespiratory arrest in infancy. He was first seen at our hospital with spastic quadriplegia caused by intracranial hemorrhage. He was admitted in order to have an operation for dislocation of rt-hip joint.

At our institution, generally we apply a heel gait cast or a high heel shoe for the equinus gait of spastic children.In this study, 10 children (4 with diplegia and 6 with hemiplegia) were evaluated using a large-sized force plate to compare the gaits of bare feet with high heel shoes.There was no remarkable change in walking velosity, step length, cadence and step width.In the patterns of reaction force, 5 showed a decreased standard deviation especially in the vertical component. The gait patterns became relatively normal in 3 cases, and 2 showed a decreased lateral component slightly. 5 cases had no remarkable change. According to these results, we considered that the net effect of high heel shoes was to result in a stable gait.

Hip and knee flexor release were performed to treat hip and knee flexion contractures and hip subluxation in cerebral palsy. This study reports on hip changes found after surgery.We followed 17 patients for over 10 years post operatively, with assessment of their locomotion, center edge angle (CE angle) and acetabular head index (AHI).Locomotion improved in 13 of the 17 cases. CE angle and AHI revealed significant improvement after surgery, there fore this operation is useful for treating hip subluxation in cerebral palsy patients.

We treated 134 cases of femoral neck fracture between 1983-1985 in our department. The age range was 60-97 years, (mean age, 77.8 years). Generally, early surgical treatment is recommended for femoral neck fracture. We compared the postoperative results and complications of such fractures in the elderly during long-term hospitalization with those of other types of patients.Most of the patients had many complications, especially senile dementia, and the resultant gait ability was not favorable when compared with other types of patients.

Spontaneous hematomyelia, a very rare condition, was encountered in one case who had hemorrhage into the cervical spinal cord. The patient was a fifty-four-year-old woman. The first sign was sudden and severe neck pain. Progression was rapid, spinal paralysis and diaphragmatic paralysis occurred two hours after the appearance of neck pain. An intramedullary tumor was suspected after examination of myelograms, etc. A cervical laminectomy, from C2 to C6, was performed. The cervical cord was enlarged and there was an intramedullary hematoma. The postoperative course was poor. and Paralysis did not improve.

It is well known that avascular necrosis of the talus may occur after fractures and dislocations of it. But the incidence of avascular necrosis is very low after fracture of the talus without displacement. In this report we describe a child with avascular necrosis of the talus after undisplaced fracture who had no treatment for fracture. This indicates that the proper treatment for talus fracture with or without displacement is necessary to avoid avascular necrosis of it.

Type II odontoid fracture classified by Anderson was treated by internal screw fixation using a small cancellous screw. This method, which was introduced by Nakanishi in 1980, has several advantages: 1. Loss of rotation at C1, C2 junction did not occur; 2. Rigid external fixation was not necessary; 3. Early mobilization of a patient was allowed; 4. Good bony union was obtained.Thus, this method may be the treatment of first choice for fresh fracture of the odontoid process.