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We evaluated an operative technique, described by the Exeter Hip Unit, to assist accurate introduction of the femoral component. We assessed whether it led to a reduction in the rate of leg-length discrepancy after total hip arthroplasty (THA).A total of 100 patients undergoing THA were studied retrospectively; 50 were undertaken using the test method and 50 using conventional methods as a control group. The groups were matched with respect to patient demographics and the grade of surgeon. Three observers measured the depth of placement of the femoral component on post-operative radiographs and measured the length of the legs.There was a strong correlation between the depth of insertion of the femoral component and the templated depth in the test group (R = 0.92), suggesting accuracy of the technique. The mean leg-length discrepancy was 5.1 mm (0.6 to 21.4) pre-operatively and 1.3 mm (0.2 to 9.3) post-operatively. There was no difference between Consultants and Registrars as primary surgeons. Agreement between the templated and post-operative depth of insertion was associated with reduced post-operative leg-length discrepancy. The intra-class coefficient was R ≥ 0.88 for all measurements, indicating high observer agreement. The post-operative leg-length discrepancy was significantly lower in the test group (1.3 mm) compared with the control group (6.3 mm, p < 0.001).The Exeter technique is reproducible and leads to a lower incidence of leg-length discrepancy after THA.Cite this article: Bone Joint J2015;97-B:154–9.

Pneumocystis jiroveciiis a life-threatening opportunistic pathogen affecting immunocompromised hosts, especially renal transplant recipients. This study reports an outbreak of seven such cases, both inpatients and outpatients, occurring in our hospital over a period of 4 months (January–April 2013). All patients were male with a median age of 38 years (range, 28–58 years); the median period between transplantation and diagnosis was 39.5 months (range, 11–123 months). One patient succumbed to the infection. Two were breakthrough cases, developing the infection while on prophylaxis, highlighting the need to view prophylaxis in light of the immunosuppression and clinical picture of such patients.

Laparoscopic donor nephrectomy has the advantages of less pain, early ambulation and shorter hospitalization compared to open donor nephrectomy. Kidney recipient surgery is, however, traditionally performed by open surgery. Our aim was to study feasibility and safety of laparoscopic kidney transplantation (LKT). After permission from Internal Review Board, LKT was performed in four patients. All kidneys were procured from deceased donors. Left kidney was used for LKT and transplanted in left iliac fossa while right kidney was used for standard open kidney transplantation (OKT). All transplantation procedures were performed successfully. Cold ischemia time varied between 4 h and 14 h. For LKT, mean time for anastomosis was 65 (range 62–72) min, mean operative time was 3.97 (range 3.5–5) h, mean blood loss was 131.25 mL (range 45–350) mL. Mean wound length was 7 cm in LKT group and 18.4 cm in OKT group. Delayed graft function was observed in one patient in each group. One patient was lost in OKT group due to posttransplant bacterial meningitis. At 6 months, both groups have comparable value of serum creatinine. In conclusion, LKT is technically feasible and safe. Long term outcome needs to be evaluated in a larger study.

Laparoscopic donor nephrectomy has the advantages of less pain, early ambulation and shorter hospitalization compared to open donor nephrectomy. Kidney recipient surgery is, however, traditionally performed by open surgery. Our aim was to study feasibility and safety of laparoscopic kidney transplantation (LKT). After permission from Internal Review Board, LKT was performed in four patients. All kidneys were procured from deceased donors. Left kidney was used for LKT and transplanted in left iliac fossa while right kidney was used for standard open kidney transplantation (OKT). All transplantation procedures were performed successfully. Cold ischemia time varied between 4 h and 14 h. For LKT, mean time for anastomosis was 65 (range 62–72) min, mean operative time was 3.97 (range 3.5–5) h, mean blood loss was 131.25 mL (range 45–350) mL. Mean wound length was 7 cm in LKT group and 18.4 cm in OKT group. Delayed graft function was observed in one patient in each group. One patient was lost in OKT group due to posttransplant bacterial meningitis. At 6 months, both groups have comparable value of serum creatinine. In conclusion, LKT is technically feasible and safe. Long term outcome needs to be evaluated in a larger study.

Purpose:Brain abscesses often present an aetiological dilemma. Microscopy is insensitive and culture techniques are time consuming. Hence, a new rapid technique in vitroProton Magnetic Resonance Spectroscopy (1HMRS) was evaluated for its usefulness in the identification of aetiology of brain abscesses. Materials and Methods:A total of 39 pus specimens from brain abscesses were subjected to in vitro1HMRS. These pus specimens were also processed by conventional culture methods. The spectral patterns generated by in vitro1HMRS were further correlated with culture results. Results:Pus specimens which showed the presence of anaerobes on culture revealed the presence of multiplet at 0.9 ppm (100%), lactate-lipid at 1.3 ppm (100%), acetate at 1.92 ppm (100%) and succinate at 2.4 ppm (75%). Pus specimens that revealed the presence of facultative anaerobes on culture showed a pattern B, i.e., the presence of lactate-lipid at 1.3 ppm (100%), acetate at 1.92 ppm (88.88%) along with the multiplet at 0.9 ppm (100%). Pattern C was seen in aerobic infection which showed the presence of lactate-lipid at 1.3 ppm (100%) along with the multiplet at 0.9 ppm. Pus from two tuberculous abscesses showed the complete absence of multiplet at 0.9 ppm. Conclusions:We observed in this study that it was possible to differentiate bacterial and tuberculous brain abscesses using in vitro1HMRS. Further, it was also possible to distinguish between aerobic and anaerobic brain abscesses on the basis of spectral patterns. In vitro1HMRS of fungal and actinomycotic brain abscess are also presented for its unusual spectra.

Purpose:The non-sporing anaerobes cause a wide spectrum of infections. They are difficult to culture and their identification is tedious and time-consuming. Rapid identification of anaerobes is highly desirable. Towards this end, the potential of nuclear magnetic resonance (NMR) spectroscopy for providing a fingerprint within the proton spectrum of six genera belonging to anaerobes reflecting their characteristic metabolites has been investigated. Methods:NMR analysis was carried out using Mercury plus Varian 300 MHz (7.05 T) NMR spectrophotometer on six different anaerobes. These included Bacteroides fragilis, Prevotella melaninogenica, Prevotella denticola, Fusobacterium necrophorum, Peptococcus nigerand Peptostreptococcusspp. After the NMR analysis (256/512 scans), the different peaks were noted. The eight pus specimens, which yielded pure culture of anaerobe, also were analysed similarly. Results:The major resonances of multiplex of amino acids/lipid at 0.9 ppm along with lactate/lipid at 1.3 ppm, acetate at 1.92 ppm and multiplex of lysine at 3.0 ppm remained constant to label the organism as an anaerobe. There was a difference found in the MR spectra of different genera and species. A simple algorithm was developed for the identification of the six different anaerobes studied. The MR spectra of the pure culture of the organism matched the MR spectra of pus from which the organism was isolated. Conclusions:MR-based identification was of value in the identification of anaerobes. However, a larger database of the peaks produced by anaerobes needs to be created for identification of all genera and species. It could then have the potential of diagnosing an anaerobic infection in vivoand thus expedite management of deep-seated abscesses.

Molecular dynamics simulations have been used to delineate the pressure dependence of conformational dynamics in polyethylene. Chain dynamics have been studied as a function of pressure (0−25 kbar) at 400 K and as a function of temperature (280−450 K) at an elevated pressure of 10 kbar. The volumetric glass transition is found isobarically (10 kbar) at ~315 K and is considerably elevated from the ~220 K atmospheric pressure value. On increasing pressure at constant temperature, the system displays several signatures indicative of the vitrification process that are complementary to those previously found to be associated with lowering of temperature. These include a large increase in autocorrelation function relaxation times, divergence of the relaxation times from conformational transition rates, an increase in spatial heterogeneity of the distribution of conformational transition rates over the various bonds, and an increase in self-correlation of the conformational transitions. Isobarically at high pressure (10 kbar), the variation with temperature of the relaxation times associated with the decay of the dipolar autocorrelation function is in accord with dielectric relaxation experiments. Upon lowering the temperature, the relaxation times diverge from the conformation transition rates, an effect also observed at low pressure.

A molecular dynamics simulation has been carried out on a model for the nematic melt phase of a thermotropic liquid crystalline polymer of the Vectra type, a 70/30 random copolymer of p-hydroxybenzoic acid (HBA) and 2-hydroxy-6-naphthoic acid (HNA). The periodic simulation box, which contained 12 chains of 10 monomers each, was orthorhombic in shape, and its a, b, and c dimensions could independently adjust under constant pressure. The X-ray scattering pattern calculated for the melt is in good agreement with experimental results. Analysis showed the chains to be highly disordered conformationally in that the dispositions of successive ester group directions and aromatic ring staggers were found to be distributed over all four available positions, at ca. ± 60° and ±120°. Translational register of chains, a feature believed to be present experimentally in the 3D ordered or “crystalline” lower temperature state, is found here to be present also in the nematic melt state. Thus, conformational disorder appears to be the principal distinction between the melt and the lower temperature ordered state. The melt remains in the nematic state on cooling to ambient temperature in the simulations.

The molecular geometries and conformational energies of nitramide and dimethylnitramine (DMNA), determined from high-level quantum chemistry calculations, have been used in parametrization of a classical potential function suitable for simulations of DMNA. A thorough investigation of basis set size and electron correlation effects on the geometry and conformational energies of nitramide, for which accurate experimental data exist, has allowed us to establish the level of theory required to obtain accurate geometries and energies for nitramine compounds. These investigations revealed the importance of electron correlation for both the geometries and relative conformational energies in nitramines. The quantum-chemistry-based force field for DMNA was validated by comparing gas- and liquid-phase properties obtained from molecular dynamics simulations with available experimental data. The gas-phase radial distribution function obtained from simulation is in good agreement with that obtained from electron diffraction experiments and is consistent with a Cs ground-state geometry for DMNA as predicted by quantum chemistry. The pressure−volume−temperature properties and solubility parameters for the bulk liquid are in very good agreement with available experimental measurements. The correlation time and activation energy associated with molecular reorientation is found to be in good agreement with NMR measurements.

Abstract: In this work, the role of the microstructure in the stress sulfide cracking (SSC) resistance of an API X-80 steel was investigated by exposure of as-received and heat-treated specimens to a H2S-saturated aqueous National Association of Corrosion Engineers (NACE) solution. It was found that for similar corrosive environments and applied stress intensity factors of 30 to 46 MPa√m, crack growth in LEFM (linear elastic fracture mechanics) compact specimens is strongly influenced by heat treating. In the as-received alloy, crack growth in the direction normal to rolling was controlled by metal dissolution of the crack tip region in contact with the corrosive environment, with crack growth rates of the order of 1/W(da/dt)∼8.3×10−4 h−1. Alternatively, crack growth in the direction parallel to the rolling direction did not show metal dissolution, but instead hydrogen embrittlement along segregation bands. In this case, crack growth rates of the order of 1.2×10−3 h−1 were exhibited. In the martensitic condition, the rate of crack propagation was relatively fast (1/W(da/dt)∼4.5×10−2 h−1), indicating severe hydrogen embrittlement. Crack arrest events were found to occur in water-sprayed and quenched and tempered specimens, with threshold stress intensity values (K ISSC) of 26 and 32 MPa√m, respectively. Apparently, in the water-sprayed condition, numerous microcracks developed in the crack tip plastic zone. Crack growth occurred by linking of microcracks, which were able to reach the main crack tip. In particular, preferential microcrack growth occurred across carbide regions, but their growth was severely limited in the ferritic matrix. Quenching and tempering (Q&T) resulted in a tempered martensite microstructure characterized by fine distribution carbides, most of which were cementite. In this case, the crack path continually shifted to follow the ferrite interlath boundaries, which contained mostly fine cementite precipitates. As a result, the crack was tortuous with numerous bifurcations along ferrite grain boundaries. Most of the tests were carried out in NaCl-free NACE solutions; the only exception was the as-received condition where 5 wt pct NaCl was added to the sour environment. In this case, crack growth did not occur after exposing the specimen to the salt-free NACE solution for 30 days, but addition of 5 pct NaCl promoted crack propagation.

Growth hormone (GH) stimulates metabolic activity. The purpose of this study was to examine whether it is involved in the aging process by increasing oxidative stress. Inorganic peroxides and lipid peroxides were measured in kidney and liver samples in dwarf mice that are deficient in GH, prolactin and thyrotropin and in transgenic mice that produce high levels of GH. In normal male mice, there was an increase in inorganic peroxides in the kidney with age. Levels were lower in old male dwarfs when compared with normal male mice of similar age. Unexpectedly, concentrations of inorganic peroxides were frequently lower in transgenic male and female mice expressing extra copies of GH than in normal controls. Lipid peroxide concentrations were more variable. Transgenic animals expressing bovine GH had the highest levels of lipid peroxides. In dwarfs, kidney levels were similar to those of normal mice but concentrations in the liver were more variable. This study does not indicate that the decrease in life span in transgenic mice producing high levels of GH is due to an increase of oxidative stress. Rather, it suggests that expression of extra copies of the GH gene may lead to a compensatory increase in antioxidant protection.Growth hormone (GH) stimulates metabolic activity. The purpose of this study was to examine whether it is involved in the aging process by increasing oxidative stress. Inorganic peroxides and lipid peroxides were measured in kidney and liver samples in dwarf mice that are deficient in GH, prolactin and thyrotropin and in transgenic mice that produce high levels of GH. In normal male mice, there was an increase in inorganic peroxides in the kidney with age. Levels were lower in old male dwarfs when compared with normal male mice of similar age. Unexpectedly, concentrations of inorganic peroxides were frequently lower in transgenic male and female mice expressing extra copies of GH than in normal controls. Lipid peroxide concentrations were more variable. Transgenic animals expressing bovine GH had the highest levels of lipid peroxides. In dwarfs, kidney levels were similar to those of normal mice but concentrations in the liver were more variable. This study does not indicate that the decrease in life span in transgenic mice producing high levels of GH is due to an increase of oxidative stress. Rather, it suggests that expression of extra copies of the GH gene may lead to a compensatory increase in antioxidant protection.

The molecular geometries and conformational energies of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) and 1,3-dimethyl-1,3-dinitro methyldiamine (DDMD) and have been determined from high-level quantum chemistry calculations and have been used in parametrizing a classical potential function for simulations of HMX. Geometry optimizations for HMX and DDMD and rotational energy barrier searches for DDMD were performed at the B3LYP/6-311G** level, with subsequent single-point energy calculations at the MP2/6-311G** level. Four unique low-energy conformers were found for HMX, two whose conformational geometries correspond closely to those found in HMX polymorphs from crystallographic studies and two additional, lower energy conformers that are not seen in the crystalline phases. For DDMD, three unique low-energy conformers, and the rotational energy barriers between them, were located. In parametrizing the classical potential function for HMX, nonbonded repulsion/dispersion parameters, valence parameters, and parameters describing nitro group rotation and out-of-plane distortion at the amine nitrogen were taken from our previous studies of dimethylnitramine. Polar effects in HMX and DDMD were represented by sets of partial atomic charges that reproduce the electrostatic potential and dipole moments for the low-energy conformers of these molecules as determined from the quantum chemistry wave functions. Parameters describing conformational energetics for the C−N−C−N dihedrals were determined by fitting the classical potential function to reproduce relative conformational energies in HMX as found from quantum chemistry. The resulting potential was found to give a good representation of the conformer geometries and relative conformer energies in HMX and a reasonable description of the low-energy conformers and rotational energy barriers in DDMD.

On the basis of all the published data, the 90 cervicothoracic muscle types found in the Lepidoptera are classified and their distribution among the various species is indicated. The muscles are grouped into 19 topographical categories under each of the four body regions: cervix, prothorax, mesothorax, and metathorax. A brief morphological discussion is given for each muscle type, and some information on its representation in other neuropteroid insects is included.

A conformational energy model has been set up for poly(ethylene terephthalate) (PET) for use in molecular dynamics simulations. The molecular dimensions, as expressed by the characteristic ratio, and the dipolar correlation factor of PET are key parameters in the simulations because they depend very differently on the conformational characteristics of the individual bond types in the chain. These parameters as well as the equation of state of the melt were emphasized in testing the model, and satisfactory representation was accomplished. It was found, however, difficult to achieve the experimental glass volume in MD cooling experiments below Tg. Packing features of bulk PET are discussed in terms of radial distribution functions. Dipolar correlation was found to be largely intramolecular in nature.

Each of the 19 categories under which we have classified the cervicothoracic musculature is discussed. On the basis of this information and other considerations the cervical, prothoracic, mesothoracic, and metathoracic regions are compared.Indications are that the cervix plus prothorax represents only a single segmental entity.The conspicuous differences between the prothoracic and pterothoracic regions are correlated primarily with: (1) reduction in the motor powers of the forelegs; (2) close association of the prothorax with the mobile head; and (3) development of wings on the pterothoracic segments.

The cervicothoracic musculature of Manduca sexta (Johannson) and of Spodoptera eridania (Cramer) is described and figured. This brings to 12 the number of lepidopterous families that have been so treated, and thus places the Lepidoptera in an exceptionally favourable position for analysis of their general muscular complement. The description of muscles for Manduca and Spodoptera is given in a form that provides a comprehensive classification of the cervicothoracic muscles of this order.

A detailed illustrated account of the nervous system in S. gregaria is given. The central, peripheral and sympathetic nervous systems have been described. The central and peripheral nervous systems comprise the brain, ventral nerve cord, suboesophageal, three thoracic and five abdominal ganglia and their nerves to different parts of the body. The brain consists of proto, deuto and tritocerebrum. The suboesophageal ganglion lies below the oesophagus and is connected to the tritocerebral lobes by a pair of connectives. This ganglion gives off a pair of recurrent nerves and seven pairs of nerves supplying the mouthparts, cervical muscles, salivary ducts and prothoracic ventral longitudinal muscles. The first or prothoracic ganglion gives off a pair of recurrent nerves and five pairs of nerves supplying different prothoracic muscles, sensillae of the prosternum and forelegs. The second or mesothoracic ganglion also gives off a pair of recurrent nerves and five pairs of nerves innervating hypodermis, forewings, middle legs, different muscles of the mesothorax and the chordotonal organ. The third or metathoracic ganglion gives off five pairs of metathoracic nerves and six pairs of abdominal nerves; the thoracic nerves supply the hindwings, metasternal sensillae, various muscles and hindlegs while the abdominal nerves include dorsal and ventral nerves of the first, second and third abdominal segments supplying the abdominal muscles, pleuron, tympanum and spiracles. The dorsal nerves of the second to eighth abdominal segments form VNABIC which supply the lateral muscles and spiracle in the respective segment. The first four abdominal ganglia, i.e. fourth, fifth, sixth and seventh abdominal ganglia give off one dorsal and one ventral nerve supplying the dorsal and ventral muscles in the respective segment. In the female the ventral nerve of the seventh abdominal ganglion also innervates the oviduct. The eighth abdominal ganglion gives off six pairs of nerves which supply the muscles of the eighth, ninth and tenth abdominal segments, epiproct, paraproct, cerci and rectum. This ganglion in the male also supplies the complex genital organ and in the female sends nerves to different valves of the ovipositor. The sympathetic nervous system is divisible into stomatogastric nervous system consisting of frontal ganglion, oesophageal ganglion, hypocerebral ganglion and their nerves and ventral sympathetic nervous system comprising a single median nerve, transverse nerves and paramedian nerves.

The dorsal diaphragm extends from first to the tenth abdominal segment while the ventral diaphragm from prothorax to the eighth abdominal segment. Eight pairs of alary muscles are located in second to ninth abdominal segment. The dorsal vessel, extending from the frons to the tenth abdominal segment, is divisible into heart and aorta. There are eight heart chambers located in the second to ninth abdominal segment. The aorta in the mesothorax, metathorax and first abdominal segment bears ampullae; it extends into the head and ends in a funnel appressed to the frons. A membranous flap-like, triradiate structure is attached to the dorsal wall of the aorta near the oesophageal ganglia. The dorsal vessel bears seven pairs of ventro-lateral excurrent ostia and twelve pairs of dorso-lateral incurrent ostia, the latter bearing internal valves. In the neck region the dorsal vessel is supported by a median dorsal septum. The caudal end of the last heart chamber is attached to the tenth abdominal tergite by a ligament. Pericardial cells are circular with granulated cytoplasm and one or two nuclei and are found scattered along the dorsal vessel in the abdomen, on the thoracic ampullae, dorsal diaphragm and on some portions of the alary muscles. The pericardial cells in the abdominal region serve as supporting cells connecting the dorsal wall of the heart with the tergum. Phagocytic cells are flattened with incomplete cell walls and large nucleus, and are found on the dorsal diaphragm up to the fourth abdominal heart chamber. A pair of antennal ampullae located just below the edge of the antennal sockets communicate with the antennae.

The line shifts for (111), (112), (113), (131) and (114) Bragg reflections have been investigated in the case of uranium deformed by cold-rolling. The Bragg maxima for different lines are found to shift towards either lower or higher values. It is shown from experiments on cold-rolled specimens subjected to etching that these peak shifts are not due to intergranular stresses. In view of low deformation stacking-fault probability the observed peak shifts are attributed to changes in d-spacing values due to change in lattice parameters of the cold-rolled uranium. The probability of point defects (lattice vacancies) aggregates introduced during cold-work, causing a 'relaxation' of the lattice, has also been discussed.

A study was undertaken to evaluate the efficacy of commercially available antimicrobial discs manufactured by Oxoid, UK, HiMedia Laboratories, Mumbai and Span Diagnostics, Surat. The discs were evaluated for their performance on the basis of percentage of coefficient of variation (%CV) which is a measure of reproducibility, mean zone diameters which is a measure of accuracy and range of zone diameter using both standard ATCC strains and clinical isolates. The data showed variation for all three manufacturers and therefore routine and regular quality control of discs as well as meticulous following of good laboratory practices is strongly advocated in clinical laboratories

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

The largest number of the vectors of plant viruses, next to aphids, is to be found among the leafhoppers. That certain plant viruses multiply in their vectors was first shown with those viruses transmitted by leafhoppers (Black 1959). Gil-Fernandez and Black (1965) studied the internal anatomy of the leafhopper, Agallia constricta (Van Duzee), a vector of the wound-tumor virus (WTV). Such an investigation was prerequisite to a study of the site or sites of multiplication of WTV in the vector. Gil-Fernandez and Black reported that there is no true filter chamber in A. constricta, but that the insect had a primitive type of filtering apparatus represented by a region where the anterior and posterior ends of the mid-intestine are apposed. They show the esophagus leading directly to the ventriculus (Gil-Fernandez and Black 1965, Fig. 1A). The main purpose of the present investigation was to study ventral surface. Inside the filter chamber the mid-intestine forms a simple loop, then, after emerging from the filter chamber, continues backward as the hind-intestine. The 2 pairs of malpighian tubules arise from the junction of mid- and hind-intestine inside the filter chamber and extend backward to their attachment to the anterior part of the rectum. Near its posterior end the hind-intestine forms a swollen rectum before opening to the exterior through the anus.

The ring-legged earwing, Euborellia annulipes (Lucas), was studied in the laboratory, at 68°–84°F and with a daily light period of about 10 hr. Plastic refrigerator boxes and Pyrex crystallization dishes, containing a 3:1 mixture of moist soil and coarse sand, were used for rearing. Powdered dog meal, supplemented occasionally with freshly killed insects and sowbugs, served as food for nymphs and adults. Details considered include distribution in the United States, economic importance, habits, reflex immobilization, autotomy, cleaning, function of the forceps, parasites and predators, and control, as well as mating behavior, nidification, oviposition, maternal care, and the several life-history stages. Oviposition began 1–23 days after mating, occurred throughout the year (usually at night), and averaged 52.7 eggs/clutch. Some females laid 4 clutches, on successive days. Minimum incubation periods in different clutches were 6–17 days, and hatching continued 2–4 days. Usually there were 5 nymphal stadia with average durations as follows: first, 10 days; second, 9.5 days; third, 11.5 days; fourth, 14.1 days; and fifth, 18.3 days. Four out of 33 individuals had a sixth nymphal stadium which averaged 20.2 days. Characters useful for distinguishing the nymphal instars include body length, width of head, length of prosternum, length and width of pronotum, total number of antennal segments, and number of segments in the “middle region” of the antennae, though considerable overlap between instars was found in some of these.