Data compilation on the effect of grain size, temperature, and texture on the strength of a single-phase FCC MnFeNi medium-entropy alloy

This data article presents a compilation of microstructural and mechanical data regarding the ternary single-phase FCC MnFeNi medium-entropy alloy (MEA). For the analysis, interpretation, and comparison of the data to literature values, the reader can refer to the original related research article entitled "Effect of Temperature and Texture on Hall-Petch Strengthening by Grain and Annealing Twin Boundaries in the MnFeNi Medium-Entropy Alloy", see Schneider et al. (Metals 9, 2019, 84). The microstructural data reported here include: (i) raw backscatter electron (BSE) micrographs (tif-files) obtained using a scanning electron microscope (SEM) for nine different grain sizes with four images for each grain size and (ii) pdf reports and tables shown below presenting the distributions of the grain- (d, accounting for grain boundaries only) and crystallite- (c, which accounts for both grain and annealing twin boundaries) sizes and of the annealing twin thicknesses (t). These datasets may be useful to develop new algorithms for the automated evaluation of microstructural parameters in recrystallized alloys, i.e. with these benchmark data, an algorithm for image analysis could be trained to assess the above mentioned microstructural parameters. This would help to speed up the analysis of microstructures and improve its reliability. Additional tables describing the recrystallized microstructures and texture include the average number of annealing twin boundaries per grain (n), and the average Taylor factors (M). Raeisinia et al. (Model. Simul. Mater. Sc. 16, 2008, 025001) recently used a viscoplastic model to show that differences in the distribution of microstructural parameters affect the Hall-Petch parameters, but no attempt has been carried out so far to experimentally investigate this possibility since grain size distributions are rarely reported. Here, our benchmark data (e.g. distribution in grain/crystallite sizes, annealing twins per grain, distribution of annealing twin thicknesses) could be used to address these issues. The data describing the mechanical properties reported here are excel-sheets of raw stress-strain curves for temperatures ranging from 77 K to 873 K and different grain sizes. The yield stress (σ 0.2% ) and the normalized Hall-Petch parameters (σ 0 /G and k y /Gb 2) are given for all temperatures. The normalized Hall-Petch parameters are reported here since they allow to better compare the strength and the magnitude of grain boundary strengthening of different alloys with the same crystallographic structure, see Cordero et al. (Int. Mater. Rev. 61, 2016, 495-512). Moreover, the Hall-Petch parameters as well as the mechanical data reported here could be used for data mining and implemented in programs used for alloy design.

Specific antibody responses as indicators of treatment efficacy for visceral leishmaniasis

Acute visceral leishmaniasis (VL) is caused by infection with parasites of the Leishmania donovani complex and may be fatal if not treated. Early diagnosis and efficacious treatment are the keys to effective VL management and control. Novel regimens are being developed to overcome limitations in VL treatment options, which are currently restricted by high costs, severe systemic side effects, and unresponsiveness. Although simple and accurate serological tests are available to help confirm VL, none are suitable to monitor treatment efficacy and cure. Here, we confirm that serum antibody responses to the diagnostic antigens rK39 and rK28 are unaltered by treatment, but demonstrate that antibodies produced against two antigens, rK26 and rK18, can be used as an indirect measure of parasite clearance. The levels of anti-rK18 and -rK26 antibodies were high in patients at initial diagnosis but declined in patients treated with either SSG (Ethiopia) or AmBisome (Bangladesh). Taken together, we propose that serological tests which measure antibodies to rK26 and rK18 merit consideration as potential markers of treatment success and cure.

Biomarkers for intracellular pathogens: establishing tools as vaccine and therapeutic endpoints for visceral leishmaniasis

Visceral leishmaniasis in South Asia is a serious disease affecting children and adults. Acute visceral leishmaniasis develops in only a fraction of those infected individuals, the majority being asymptomatic with the potential to transmit infection and develop disease. We followed 56 individuals characterized as being asymptomatic by seropositivity with rk39 rapid diagnostic test in a hyperendemic district of Bangladesh to define the utility of Leishmania-specific antibodies and DNA in identifying infection. At baseline, 54 of the individuals were seropositive with one or more quantitative antibody assays and antibody levels persisted at follow up. Most seropositive individuals (47/54) tested positive by quantitative PCR at baseline, but only 16 tested positive at follow up. The discrepancies among the different tests may shed light on the dynamics of asymptomatic infections of Leishmania donovani, as well as underscore the need for standard diagnostic tools for active surveillance as well as assessing the effectiveness of prophylactic and therapeutic interventions.

Small free vascularized iliac crest bone grafts in reconstruction of the scaphoid bone: a retrospective study in 60 cases

Carpal instability may result in progressive degenerative arthritis of the wrist. The surgical goal of the reconstruction of scaphoid nonunion is to achieve bone union and to restore the scaphoid. Many procedures are described to treat scaphoid nonunion for different indications. This retrospective study reports on the anatomical fundamentals, the operative procedure, and the results of 60 patients (21 with recalcitrant scaphoid nonunion that lasted longer than 4 years, 26 with an avascular pole fragment, and 13 with scaphoid nonunion after previous surgery) who were treated by a small free vascularized iliac crest bone graft. All 60 patients have routinely been followed up clinically and with magnetic resonance imaging. Union was achieved in 91.7 percent by improvement of stability and the compromised vascularity of the scaphoid. The bone flap loss rate and persisting nonunion was 8.3 percent, leading to progressive arthritis and carpal collapse. Complaints concerning discomforts caused by the scar were heard from 40.1 percent of the patients, and 31.7 percent complained of discomforts caused by the bony deformity. Bone deformations on the donor site were detected radiologically in 63.3 percent of the patients. In 31.7 percent, an impairment of the lateral femoral cutaneous nerve was noted. Reconstruction of the scaphoid by means of implantation of a vascularized iliac bone graft proved efficient to treat avascular recalcitrant scaphoid nonunion and pseudarthrosis with avascular proximal pole fragments.

[Dorsal dislocation of the proximal interphalangeal joints of the finger. Results after static and functional treatment]

In a follow-up examination of 30 patients who had sustained dorsal dislocations of the PIP joint, the results of two conservative therapy regimens, either immobilisation or early motion were investigated. In Group A, 15 patients were treated by closed reduction and immobilisation with a forearm cast for four weeks. Nine patients showed normal range of motion, whereas a limitation of extension of ten degrees and more was seen in six cases. All PIP joints were stable. Nine patients were satisfied. Three patients complained of a limitation of extension, two of a limitation of extension and pain and one of swelling. In Group B, 15 patients were treated by dorsal block splinting of the PIP joint following reposition. The finger was released in extension with daily active exercise of the PIP joint. Only two of 15 patients showed limitation of extension, whereas 13 cases showed normal range of motion. Instability of one collateral ligament was seen in two cases. Palmar instability did not occur. Eleven patients were satisfied. One patient complained of instability, pain and lack of extension, one of pain in combination with instability, one of pain and one of swelling of the joint.

[Late sequelae of fractures of the distal third of the forearm during the growth period]

Fractures to the distal third of the forearm are the most common fractures of the upper extremity, with the majority occurring between the age of ten and 14 years. With the exception of the rare epiphyseal fractures, they have a favourable prognosis. The present study investigates the frequency and extent of potential clinical and radiological late sequelae of fractures in the distal third of the forearm during growth. Of the patients treated at the Innsbruck University Department of Traumatology from 1980 to 1992, 220 patients of a growing age with 232 closed fractures in the distal third of the forearm were followed up. The radius alone was affected in 60% of these cases; the radius and the ulna in 40%. Fractures of the ulna alone were not present. The mean age of the patients at the time of injury was nine years (range one to 16 years) and the mean time of follow-up ten years (range five to 16 years). In addition to the patient's subjective assessment, the right and left sides were compared with regard to mobility of the wrist and rotational movement of the forearm. Based on standard X-rays, the frontal (radio-ulnar) and lateral (dorso-palmar) radial joint angle as well as the difference in the radio-ulnar plane were compared with the contralateral side. Clinical and radiological findings were summarised into an overall result. 19% of the patients reported pain in the injured wrist. Mobility of the wrist in the sagittal and/or frontal plane was limited in 5% of patients and rotation of the forearm was limited in 16% of patients. A statistically significant accumulation of limited rotation was seen after physeal fractures of the ulna ("one-way" ANOVA-test, p = 0.0033). A difference between the left and right side in regard to the frontal radial joint angle was seen in 6% of patients and a difference in the lateral radial joint angle was registered in 2% of patients. A difference in the radio-ulnar plane was observed in 37% of patients. In the presence of relative ulna-plus variance, 75% of patients complained of pain in the ulnocarpal compartment of the wrist. In these patients, dynamic magnetic resonance tomography revealed a compression of the ulnocarpal disk between the proximal carpal bones and the head of the ulna, as well as degeneration in the central portion of the disk. The overall outcome was very good in 72%, good in 19%, moderate in 6% and poor in 3% of patients. The younger the children had been at the time of injury, the more favourable were the results (chi-square test, p = 0.009). Children older than ten years of age with an angulatory deformity of more than 20 degrees and/or fragment dislocation over half of the breadth of the shaft at fracture consolidation showed the poorest results. Further factors having a negative influence on the outcome were repeated reduction manoeuvres and an additional fracture of the ulna.

[Monteggia injuries in childhood]

The Monteggia-fracture dislocation is a characteristic combined injury of the forearm with fracture of the ulna and dislocation of the head of the radius. Monteggia- and equivalent injuries are rare. In the present study, we attempt to clarify the concept of therapy and observe the influence of this injury on the growth of the forearm bones. Between 1977 and 1996, 27 patients (three to thirteen years) with a Monteggia or a Monteggia-equivalent injury were treated. We present clinical and radiological long-term results of 20 patients, two to 21 years following the injury. Group I includes 12 patients with a classic Monteggia injury, five patients were treated conservatively, seven patients surgically. Ten patients were free of pain and had no loss of motion. In one patient there was a loss of pronation following an accompanying injury of the distal radius. Primary paresis of the radial nerve has a good prognosis. One patient presents a persisting dislocation of the radius head with a loss of flexion in the elbow joint, and a secondary persisting paraesthesia of the median nerve. Group II includes eight patients with a Monteggia-equivalent injury; all of them were treated surgically. The results in this group showed more loss of motion in elbow function, forearm rotation, and dislocation of the axis in the elbow joint. Monteggia and Monteggia-equivalent injuries in childhood have good functional results if correct reduction of the fracture of the ulna and the head of the radius is performed. If this is not possible conservatively, patients need open reduction and internal fixation.

Informational masking in normal-hearing and hearing-impaired listeners

The present study aimed to test whether central, across-channel, informational auditory processing abilities are altered by hearing loss. The informational masking effect exerted on a 1 kHz tone-pip by a simultaneous four-tone masker, whose spectral content changed within as well as across trials, was measured in the left and right ears of normal-hearing subjects and hearing-impaired subjects with either symmetrical or asymmetrical hearing loss between the two ears. In the subjects with normal-hearing or symmetrical hearing loss, the level of the masker was set to 40 dB SL in each ear, in the subjects with asymmetrical hearing loss, the masker was set to 40 dB SL in the best ear and loudness-balanced in the other ear. The results failed to reveal significant differences in informational masking between normal-hearing and hearing-impaired subjects. However, in subjects with asymmetric hearing loss, less informational masking was observed in the ear with the more elevated absolute thresholds than in the opposite ear. Since the latter finding can be explained in terms of across-ear differences in loudness recruitment, it is suggested that central, across-channel, informational processing abilities are not substantially different in hearing-impaired than in normal-hearing ears.

The use of a graft from the second extensor compartment to reconstruct the A2 flexor pulley in the long finger

A 10 mm wide ring graft from the second extensor compartment with periosteum from the floor of the sheath was used to correct bowstringing in six patients who sustained an isolated rupture of the A2 pulley. It was attached to the lateral rims of the sheath. Periosteum was used for additional graft fixation. Bowstringing was assessed by magnetic resonance imaging and ultrasound preoperatively and 19.5 months after surgery. It was corrected in five patients and improved in one. Pain was reduced from 35 to 7 points on a visual analogue scale. Digital circumference decreased from 76 to 71 mm. Flexion at the PIP joint increased from 88 degrees to 116 degrees. Pinch grip improved from 28 to 56 N.

Vascularized bone graft from the iliac crest for the treatment of nonunion of the proximal part of the scaphoid with an avascular fragment

BACKGROUND

It was hypothesized that nonunion of the proximal third of the scaphoid associated with avascular necrosis could be treated successfully with a free vascularized bone graft obtained from the iliac crest.

METHODS

Fifteen patients who had a nonunion of the proximal part of the scaphoid that had been present for an average of two years and three months (range, nine months to seven years) were managed with use of a free vascularized bone graft obtained from the iliac crest. Avascularity of the scaphoid, as assessed on preoperative radiographs, was characterized by loss of trabecular structure, collapse of subchondral bone, and formation of bone cysts. The results of the procedure were assessed in terms of osseous union, pain, active motion of the wrist, and osteoarthritis. Postoperatively, vascularity of the scaphoid was evaluated with use of magnetic resonance imaging and color Doppler ultrasonography. The average duration of follow-up was six years and one month (range, two years and one month to eight years and one month).

RESULTS

Preoperatively, one patient had had pain with any movement of the wrist and fourteen had had pain after strenuous manual labor or sports activity. The average pain score, derived with use of a 10-point visual analog scale, was 2.4 points (range, 1.0 to 6.7 points). Postoperatively, union was achieved in twelve patients; six were pain-free, and six had occasional pain during strenuous manual labor or sports activity, or both. The average pain score for these twelve patients was 1.1 points (range, 0.0 to 4.2 points) on the visual analog scale. Preoperatively, osteoarthritis was limited to the region between the radial styloid process and the distal part of the scaphoid in fourteen patients and to the radioscaphoid region in one patient. Postoperatively, the degree of osteoarthritis remained unchanged in seven of the twelve patients who had union and progressed to the radioscaphoid region in five. Vascularity, as seen on the imaging studies, was restored in all twelve patients who had union. The nonunion persisted in three patients, all of whom had progressive osteoarthritis leading to carpal collapse.

CONCLUSIONS

The index procedure was successful in twelve of the fifteen patients who had a symptomatic nonunion of the proximal part of the scaphoid associated with avascular necrosis and osteoarthritis that was limited to the radioscaphoid joint.

[Proximal scaphoid pseudarthrosis with avascular pol fragment: long-term outcome after reconstruction with microvascular pedicled iliac crest bone graft]

56 patients suffering from scaphoid nonunion with avascular necrosis of the proximal pole were treated by a free vascularized iliac bone graft. Follow-up examination of 27 patients at 8.8 years included evaluation of scaphoid nonunion, progression of arthrosis and clinical parameters. Union was achieved in 85% of the patients (Group A). Arthrosis remained unchanged in 75%. No carpal collapse occurred. 81% of the patients were painfree. Grip strength was 95% and range of motion 75% compared to the noninvolved wrist. Nonunion persisted in 15% (Group B). In all these patients carpal collapse had established. 66% of the patients showed mild pain. Grip strength was 71% and range of motion 65% of normal. Transplantation of a free vascularized iliac bone graft resulted in union of a scaphoid pseudarthrosis with avascular proximal pole in 85%. When union occurred, progression of degenerative arthrosis could be arrested and good clinical late results could be achieved.

A new approach to computer guidance in orthopedic surgery using real time volume rendering

The purpose of this paper was to evaluate the ability of a new real time volume rendering system using raw unprocessed CT data on a four processor Pentium PC. A CT data set of the pelvic area was used to demonstrate the systems ability to integrate and visualize both data from a CT scan and a tracking system. The computer system consisted of a four processor Pentium PC and the software tool VGInsight (Volume Graphics GmbH). For study purposes in a laboratory setting a magnetic tracking system (Polemus Inc.) was used to simulate tracked surgical tools. With this new software tool and the tracking system the exact relative location of a tracked instrument within all structures of the pelvic area, soft tissue as well as bone, could be displayed in 3D and real time without preprocessing of the data set. Until recently real time volume rendering required expensive workstations. With a new software tool on a four processor Pentium PC the authors were able to introduce a 3D real time processed data supply to the surgeon.

[Functional treatment of the interphalangeal joints in palmar ligament rupture]

Palmar plate injuries of the interphalangeal joints are very common, yet they require careful treatment until full functional recovery is attained. This paper presents the results of follow-up examinations of 76 patients who underwent early functional treatment with a special dynamic splint. All had sustained an injury of the palmar plate of the PIP-joint (Type 1 or 2 according to Hintringer and Leixnering). After a velcro strip is released, the splint enables daily active exercise of the PIP joint with the joint being protected laterally and protected against hyperextension. This splint was worn for four weeks. After removal of the splint, 71% of all patients indicated that they did not have any problems, while 26% achieved the same mobility as the unaffected joint of the other hand after two more weeks of dynamic splinting. In only one case motion was inhibited for several further weeks.