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Experimental measurements used to validate previous electronic band structure calculations for olivine LiFePO 4 and its delithiated phase, FePO 4 , have been re-investigated in this study. Experimental band gaps of LiFePO 4 and FePO 4 have been determined to be 6.34 eV and 3.2 eV by electron energy loss spectroscopy (EELS) and UV-Vis-NIR diffusion reflectance spectroscopy, respectively. X-ray photoemission (XPS) and Raman spectroscopy show that the surfaces of very carefully synthesized LiFePO 4 display Li-depletion, which affects optical reflectance determinations. Based on these experimental measurements, functionals for density functional theory (DFT) calculations of the electronic properties have been revisited. Overall, electronic structures of LiFePO 4 and FePO 4 calculated using sX-LDA show the best self-consistent match to combined experimentally determined parameters. Furthermore, the open-circuit voltages of the LiFePO 4 half-cell have been interpreted in terms of both Fermi levels and Gibbs free energies, which provides additional support for the electronic band structures determined by this research., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Presented in this work is a facile and quick electrochemical method for controlling the morphology of thick polyaniline (PANi) films, without the use of templates. By stepping the polymerization potential from high voltages to a lower (or series of lower) voltage(s), we successfully controlled the morphology of the polymer, and fibrous structures, unique to each potential step, were achieved. In addition, the resultant film was tested electrochemically for its viability as an electrode material for flexible batteries and supercapacitors. Furthermore, the PANi film was decorated with gold and platinum nanoparticles via an electroless deposition process for possible electrocatalytic applications, whereby the oxidation of hydrazine at the composite was investigated.

The direct electrochemical reduction of solid titanium dioxide in a chloride melt is an attractive method for the production of titanium metal. It has been estimated that this type of electrolytic approach may reduce the costs of producing titanium sponge by more than half, with the additional benefit of a smaller environmental footprint. The process utilises a consumable carbon anode which releases a mixture of CO2 and CO gas during electrolysis, but suffers from low current efficiency due to the occurrence of parasitic side reactions involving carbon. The replacement of the carbon anode with a cheap, robust inert anode offers numerous benefits that include: elimination of carbon dioxide emissions, more efficient cell operation, opportunity for three-dimensional electrode configurations and reduced electrode costs. This paper reports a study of Nb-doped titania anode materials for inert anodes in a titanium electrolytic reduction cell. The study examines the effect of niobium content and sintering conditions on the performance of Nb-doped TiO2 anodes in laboratory-scale electrolysis tests. Experimental findings, including performance in a 100 h laboratory electrolysis test, are described.

We report the synthesis of new protic ionic liquids (PILs) based on aniline derivatives and the use of high-throughput (HT) techniques to screen possible candidates. In this work, a simple HT method was applied to rapidly screen different aniline derivatives against different acids in order to identify possible combinations that produce PILs. This was followed by repeating the HT process with a Chemspeed robotic synthesis platform for more accurate results. One of the successful combinations were then chosen to be synthesised on a larger scale for further analysis. The new PILs are of interest to the fields of ionic liquids, energy storage and especially, conducting polymers as they serve as solvents, electrolytes and monomers at the same time for possible electropolymerisation (i.e. a self-contained polymer precursor).

This paper describes the design, construction and implementation of a relatively large controlled-atmosphere cell and furnace arrangement. The purpose of this equipment is to facilitate the in situ characterization of materials used in molten salt electrowinning cells, using high-energy X-ray scattering techniques such as synchrotron-based energy-dispersive X-ray diffraction. The applicability of this equipment is demonstrated by quantitative measurements of the phase composition of a model inert anode material, which were taken during an in situ study of an operational Fray-Farthing-Chen Cambridge electrowinning cell, featuring molten CaCl(2) as the electrolyte. The feasibility of adapting the cell design to investigate materials in other high-temperature environments is also discussed.

The amphiphobic nature of carbon nanotubes allows them to stabilise droplets of water-insoluble monomers dispersed in the aqueous nanotube suspension, leading to a flexible route to electrochemical synthesis of useful nanoporous composites of nanotube doped conducting polymers, and potentially to other chemistry involving reactants incompatible in the same medium.

Because of its presumed ideal reversible behavior, the oxidation of ferrocene is widely used in cyclic voltammetric studies in highly resistive organic solvents as a means of reference electrode potential calibration. In this study, it is shown that a good estimate of the uncompensated resistance value, needed for reference potential correction and also frequently an input parameter in simulation of the theory, can be obtained simultaneously with the ferrocene reference potential measurement using a simple analysis based on the semiintegral. Application to cyclic voltammetric oxidation of ferrocene in dichloromethane (0.1 M NBu4PF6), under conditions where uncompensated resistances of approximately 2.5 komega are encountered, is used to illustrate the fidelity of the semiintegral method of analysis. Inclusion of this estimated resistance value as the input parameter in a commercially available digital simulation package confirms that the oxidation of ferrocene in dichloromethane represents a close-to-ideal diffusion-controlled reversible process. However, use of the semiintegral method of data analysis also enables detection of subtle forms of nonideality encountered with the ferrocene oxidation process in other media where kinetically controlled adsorption of the ferricenium cation may occur.

A 5-year study of the injuries sustained by a single intercollegiate wrestling team is presented. The total number of injuries, a description of the injuries classified according to anatomical distribution, and mechanism of injury are given. A high incidence of upper body injuries is noted, and comments are made concerning protective measures that can be taken.

Seventy-five patients ages 40 to 95 (average, 78), 60 of whom were women and 15 men, were admitted with upper femoral fractures and participated in a study designed to evaluate the possible prophylactic effects of platelet-inhibiting drugs on the incidence of thromboembolism. Aspirin, 600 mg, b.i.d., or a combination of the above doses of aspirin and hydroxychloroquine, 300 mg, b.i.d., were used from the time of admission. The study was prospective, consecutive except for a few exclusions, double-blind and randomized. Standard surgical treatment was given by three orthopedists. Venography by the 11th day was the endpoint, although daily examinations and early impedance plethysmography were also used. Twenty-five patients received placebos, 24 aspirin alone and 26 aspirin and Plaquenil. In the control group, 15 of 25 (60%) developed thrombosis and two had nonfatal pulmonary emboli. With aspirin, six of 24 (25%) had thrombosis and one a fatal embolus. In the combination group seven of 26 (27%) developed thrombosis and there were no emboli. No significant difference existed between treatment groups, but there was significant difference between the control and treatment group at the 2% level by the Yates chi2 test. Treated women received significant protection against thromboses (p less than 0.02); 13 of 20 untreated women had deep thromboses versus 12 of 40 in the treated women. Aspirin prophylaxis is significantly useful in fractured hip patients. The combination of aspirin and Plaquenil offers no additional benefit and only leads to complications from hematomas.

The anterior cruciate ligament (ACL) was first described by Galen (circa 170 A.D.). During a period of some 1600 years, the importance of the ACL seems not to have been sufficiently appreciated. With the advent of arthroscopy, motor vehicle accidents, and professional athletics, the ACL emerged to the forefront of orthopedic problems. Hey Groves' operation (1917) forms the basis of the modern intra-articular reconstruction. Campbell (1936) described the triad of torn medial meniscus, medial collateral ligament, and ACL. In the prearthroscopy period of contemporary orthopedics, O'Donoghue (1950) advanced the research and treatment of ACL of the knees of college athletes.

This paper presents an over-all view of the injuries associated with intercollegiate and interscholastic wrestling as conducted in the United States. It classifies injuries according to the mechanism of injury in wrestling and analyzes these mechanisms together with recommendations for treatment and prevention of these conditions.

The Chrisman-Snook procedure for instability of the lateral ankle ligaments, first described in 1969, reconstructs the anterior talofibular ligament and the calcaneofibular ligament using one-half of the peroneus brevis tendon, routed through tunnels in the fibula and calcaneus. In the present long-term evaluation of the results of this procedure, forty-eight of sixty ankles, in fifty-seven patients, were assessed after a mean follow-up of ten years (range, four to twenty-four years). The results were excellent in thirty-eight ankles, good in seven, fair in two, and poor in one. The two ankles with a fair result were improved but still had some persistent instability, while the ankle with a poor result (no improvement) was in a patient with generalized ligament laxity. All three patients with a fair or poor result had had a severe reinjury to the ankle. Based on the findings in this study, we concluded that this procedure will restore good long-term function in a high percentage of patients who are disabled by ankle instability due to unhealed or neglected tears of the lateral ligaments.

It is clear that sports medicine is a very old and honorable medical specialty from the early Hindu and Chinese writings through the age of Hippocrates and Galen. From the contributions of Avicenna and Paré to Hitchcock and physicians of our own time, the specialist in sports medicine has played an important role in the development of medical techniques to promote health and fitness and to ensure the safety and well-being of everyone who participates in athletic competition.

In a prospective study extending from 1966 to 1974, the results of the Hauser procedure were compared with the Roux-Goldthwait procedure for the correction of recurrent dislocations of the patella. In 87 knees in 75 patients, repaired consecutively and in a random manner with one procedure or the other, 100% retrieval was achieved. The average follow-up period was 7.7 years. Significant complications, though not necessarily of long term, occurred in 24 of 47 knees receiving Hauser repairs as compared with 6 of 40 knees in the Roux-Goldthwait group. Satisfactory long-term results were obtained in 72% with the Hauser technique and 93% with the Roux-Goldthwait technique.

Although there were many physicians who treated athletes before Galen, I believe that he was the first to devote a major portion of his time to this field of endeavor. Furthermore, his systematic observations, his aggressive pursuit of newer and better ways of treatment, his teaching, and his publishing of his observations make him a kindred soul to the team physician and practitioners of sports medicine of today. It is for these reasons that I believe that he can justly be called the "Father of Sports Medicine."

All reported cases have occurred in the anterior tibial or rarely peroneal compartments. Case I and V in this series follow this same pattern. Case II and III are unusual in that they are the first recorded cases of this syndrome occuring in the calf of a leg. In Case IV the syndrome was present both in the anterior compartment as well as in the calf. Case III in addition, demonstrated arteriographic evidence of impairment of blood flow preoperatively which was relieved by fasciotomy. It is this author's opinion that this syndrome develops due to obstruction of venous drainage by a rise in pressure in the myofascial compartment with exercise. Perhaps it occurs in athletes because the muscle hypertrophy in these patients in greater than that in the general public and the margin of safety is reduced. It is not necessary to perform complicated or painful investigative studies to make the diagnosis. Kennelly and Blumberg state that "a convincing history is all that is necessary," and the author is in complete agreement with this statement. Fasciotomy gives complete relief and is earnestly recommended both to relieve symptoms and to prevent the catastrophic consequences of muscle necrosis. In fact, in severe cases it is best to advise cessation of physical exercise until the operation can be done in order that this severe complication does not develop.

A brief review of the injuries in women's collegiate gymnastics is presented, together with a brief analysis of the mechanisms of injury and relative frequency thereof in the different events.

In this 5-year study of women gymnasts, 70 participants (i.e., one woman for one season) sustained 66 major injuries (i.e., brought to the attention of a physician and produced disability). Forty-seven of the 70 athletes sustained injuries. The trunk had the lowest incidence of injuries (11), the upper extremity had 20, and the lower extremity had the highest incidence (35 injuries). Two categories, stress or trauma, segregated the injuries and provided rationale for the high incidence of injuries on this team. These athletes were of national caliber. They were constantly trying to improve performance. They engaged in intensive practice and difficult maneuvers. The self-motivation of these women increased the number of injuries caused by stress (a total of 21); the combination of intensive practice and the maneuvers is responsible for the traumatic injuries (45). From this evidence, women's gymnastics should be recognized as a hazardous sport for the competitor. Risk factors should be evaluated constantly by her, the coach, and the team physician.