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Diabetic Retinopathy is a medical disorder in which diabetes mellitus causes damage to the retina. Diabetic Retinopathy is diagnosed using coloured fundus pictures, which requires trained clinicians to recognise the presence and importance of several tiny characteristics, making it a time-consuming task. We present a CNN-based technique to detect Diabetic Retinopathy in fundus pictures in this research. A new segmentation strategy using Gabor filters is employed to prepare the data used to train the model. Data augmentation is used to gather enough data to train the model due to the short dataset. Intricate characteristics in fundus images are detected by our segmentation model, which also detects the presence of DR. The model is efficiently trained using a high-end Graphics Processor Unit (GPU). Keywords: Augmentation, Segmentation, CNN

Aims: In this study we are evaluating the outcome in management of distal radius fracture by closed reduction and percutaneous 5 k-wire fixation in both young and elderly patients in most types of distal radius fracture types where closed reduction is possible and where ulna is intact or reconstruct able.Material and Methods: A total of 50 patients with distal end radius fractures associated with or without other fracture were treated in in the department of Orthopaedics at all hospitals attached to SMS Medical College & Hospital, Jaipur. The patients were treated with closed reduction and 5 k-wire (1.8mm) fixation under anaesthesia. Clinical scoring system of green and o’brein modified by Cooney and Sarmiento’s modification of Lindstorm criteria was recorded.Results: The most commonly encountered complications were superficial pin tract infection (25.5%) and extensor tendon tethering (6.4%) which were less serious complications and resolved completely on removal of k –wires. Cooney modification of Green and O‘ Brien‘s score was showed higher excellent case (84%) than good (10%) and fair (6%)Conclusion: According to our study perfect closed reduction and five k-wire fixation technique is a versatile tool which provides functional outcomes better than conventional k-wire fixation and volar plating in distal end radius fractures.

Cyber-crimes are growing rapidly and to prevent these crimes one should share all the knowledge he/she has to make people aware of these attacks. In the field of Application Security there is a very well-known vulnerability ―SQL INJECTION‖. In this paper, we have focused on what are the type of SQL Injection attacks and where it can be found in any application.

Background: The fracture of distal femur are often unstable and comminuted and as difficult to treat. The incidence of complications in these fracture are relatively high .The purpose of our study was aimed to compare functional outcome between both column fixations by using distal femoral locking compression pate on lateral side and then using TENS nail on medial side to obtain support of medial column versus lateral distal femoral plate.Methods: We have included 80 patients with distal femur fracture with intercondylar extension in our study. We have treated 40 patients with distal femoral locking compression plate and support of medial wall with TENS nail and 40 patients with distal femoral locking compression plate. There were sixty six males and fourteen females. The average age of the patients was 39.08 ± 11.95 years. All the patients were operated between 3 to 9 days. All patients were followed up at 2th, 6th, 10th weeks, 3 month and 6 month regularly and evaluated for fracture healing, Clinical union was defined as a painless fracture site during full weight bearing. Radiological union was defined as bridging trabeculation across the fracture site on three of four cortices. The final outcome was assessed according to schatzker and Lambert scoring system.Results: The result was excellent in twelve, good in fifteen, fair in ten and poor in one in DFLCP with TENS nail group according to schatzker and Lambert scoring system. The result was excellent in eight, good in twelve, fair in twelve and poor in five in DFLCP group according to schatzker and Lambert scoring system. The average time to Union was 17.7 weeks in DFLCP with TENS nail group and 19.9 weeks in DFLCP group. Complications include superficial wound infection in three patients, secondary osteoarthritis in 17 patients and varus angulation in three patients in DFLCP with TENS nail group. In DFLCP group varus angulation was in eleven patients.Conclusions: The use of TENS nail for medial femoral defect along with distal femoral locking compression plate may eliminate the need of plate on medial side. The varus angulation that occurs with defect is decreased and additional long incision and operative time is avoided.

Objective: The purpose of our study is to describe our experience with the non-vascularised fibular autogenous grafts that was used for the treatment of nonunion of long bones including tibia, femur & humerus and to analyse and compare the results in terms of postoperative wound infection, radiographic evidence of union, postoperative pain and functional disability, success rate of procedure etc. with conventional iliac crest bone grafting and plating, at a tertiary care centre.Methods: The study was conducted in department of Orthopedics SMSMC, Jaipur from September 2017 to June 2019 and included 80 cases of nonunion of long bone. Amongst these, 40 cases were treated with fibular strut grafting and 40 cases were treated with iliac crest bone grafting, and all cases were followed postoperatively to compare the results in terms of demographic parameters, union time, postop complications.Result: Amongst 32 cases of nonunion of long bones treated with fibular strut 31 cases (96.9%) showed complete union in mean time interval of 17.77 weeks while only 29 (85.3 %) amongst 34 cases treated with iliac crest bone graft showed union in mean time of 18.41 weeks.Graft site pain was noted in 20.6% cases of iliac crest graft while no cases of fibular strut graft had this problem; EHL weakness was noted in 34.4% of cases and all of them recovered fully at the end of follow up.Conclusion: According to our study fibular strut is a better option in treatment of nonunion long bones as maximum cases showed complete union in less time interval and with very few postoperative complications than iliac crest bone grafting.

Background: To analyse the effect of endometrial scratching on pregnancy rates in previously failed IUI cycles Methods: Randomized control study conducted on Couples attending the Infertility Clinic, Obstetrics & Gynaecology Department, SMS Medical College, Jaipur and requiring repeat IUI were recruited for the study from Feb 2019 to November 2020. Results: women in which IUI failed two times positive results after scratching was present in 16.15% cases followed by 6.92% positive results in women who had three times IUI failed and women who had only one-time IUI failed positive results was present in 4.62% cases. In controls we found positive results with 5.38% in women having one-time IUI failed followed by 3.85% in women where two time IUI failed and only in 2.31% women positive results found having three time IUI failed. Conclusion: In conclusion this study demonstrates 2.5-3 fold increase in pregnancy rates after scratch, endometrial scratching can be a preferred option in patients with previous failed IUI cycles before opting for expensive IVF treatment. Keywords: IUI, IVF, Inferetility

Background: Methods: The present study is a single arm interventional study done at a tertiary care hospital in a metropolitan city. The study participants were the females who had infertility due to PCOS and resistant to clomiphene citrate, and participants were given HMG in a sequential manner with Clomiphene citrate and ovulation was observed using the TVS. Results: 79% of the study participants ovulated at the end of the study as a final outcome and only 25 participants who constitute 21% of the total had not ovulated. No cases of ovarian hyperstimulation and multiple gestation was reported. Conclusion: The study thus concludes that CC with low dose HMG is an efficient and safe method for induction of ovulation in females with CC resistant PCOS related infertility without the dangers of OHSS and other adverse events, also the presence of normal BMI can help in a better rate of ovulation Keywords: HMG, TVS, Infertility

The auditory system uses interaural time- and level differences (ITD and ILD) as cues to localize and lateralize sounds. The availability of ITDs and ILDs in the auditory system is limited by neural phase-locking and by the head size, respectively. Although the frequency-specific limitations are well known, the relative contribution of ITDs and ILDs in individual frequency bands in broad-band stimuli are unknown. To determine these relative contributions, or spectral weights, listeners were asked to judge the lateralization of stimuli consisting of eleven simultaneously presented 1-ERB-wide noise bands centered between 442 Hz and 5544 Hz and separated by 1-ERB-wide gaps. Interaural disparities were applied to each noise band and were roved independently on every trial. The weights were obtained using a multiple linear regression analysis. In a second experiment the effect of temporal context on the spectral weights was investigated. Ten of the noise bands were used as pre- and postcursors and listeners were asked to lateralize the stimuli. Results show that only the lowest- or highest frequency band received highest weight for ITD and ILD, respectively. Temporal context led to significantly enhanced weights given to the band without the pre- and postcursor. The weight enhancement could only be observed at low frequencies, when determined with ITD cues and for low and high frequencies for ILDs. Hence, the auditory system seems to be able to change the spectral weighting of binaural information depending on the information content.PACS43.64.-q · 43.64.+r · 87.19.lt · 43.66.-x · 43.66.+y · 43.64.Bt

Background: Untreated Perthes disease can lead to osteoarthritis by the fourth decade. The treatment is conservative for children 10 years of age at presentation. All patients had limitation of abduction and internal rotation. Eight patients (53.33%) had pain at the hip and 12 patients (80%) had limp. Mean time between diagnosis and corrective surgery was 3 weeks. Results: The evaluation was done using caput index (CI) and epiphyseal quotient (EQ) and articulotrochanteric distance radiologically, range of motion and Harris Hip Score for clinical outcome. All the measurements were carried out on pre- and postoperative X-rays after 3 years followup and compared with the contralateral normal hip. After a mean followup period of 3.4 years, we noted the statistically significant difference between pre- and postoperative values. We noted that all (100%) children in Stage IB, IIA and 50% children in Stage IIB achieved satisfactory results. There was a significant change (P = 0.000) in CI among all the patients after surgery. The final EQ after 3 years of VDRO was 0.606 and was significant (P = 0.0000). Conclusion: In our opinion, based on the encouraging short term radiological and clinical outcomes, VDRO may be regarded as a treatment procedure for late presenting Perthes disease in stage IB, IIA, IIB.

BACKGROUND: Simultaneous traumatic dislocation of both the hips in an individual is an uncommon injury. It accounts for only 1–2% of all traumatic hip dislocations. Simultaneous traumatic dislocation of both the hips in opposite directions i.e., anterior dislocation of one hip and posterior of the other is even rarer. These asymmetric dislocations need prompt identification for appropriate management. While their management should proceed in a manner commensurate with the accepted management of isolated dislocations to avoid complications, it is the timely identification which is essential. STUDY DETAILS: Retrospectively the details of three patients with asymmetric bilateral hip dislocations were collected. The article describes the clinical presentation of each patient and the management offered to them. The follow up duration ranged from 15 months to 24 months. RESULTS: In the short term, the outcomes in terms of hip pain, movements at the hips and radiological parameters like absence of arthritic or avascular changes were found to be satisfactory in each patient. CONCLUSION: Early diagnosis and prompt reduction is the essential first step in the appropriate management of these patients to prevent the possible complications. The associated fractures must be managed as per the established principles of trauma care. Long term follow up is essential for identifying if complications like avascular necrosis and secondary osteoarthritis develop after this uncommon injury.

Main driving force of this research work is to focus 9th principle (Catalysis) out of 12 principles of green chemistry so as to protect environment concerned with the reduction in generation of carbon dioxide, one of the green house gas. An innovative development of chemical pathway regarding N-alkylation reaction carried out by adding and recycling only catalytic amount of Hydrotalcite as solid base instead of stoichiometric amount, as per prior art techniques, has attempted. Synthesis of 3° amines, important Active Pharmaceutical Ingredients (APIs) and their intermediates, maintaining the same quality attributes resulting in to minimum generation of carbon dioxide are described. These concept is designed, synthesized, characterized, quantified and compared using “Carbon Efficiency”, a Green Chemistry Metrics, with already reported work to prove its sustainability. It is industrially advantageous by getting improvement in carbon efficiency and yield as outcome. Here we show a practical greener approach towards Carbon – Nitrogen bond formation with the help of calculation of Carbon efficiency and rate of reaction for first time.

Objective: This compares hospital suction negative pressure wound therapy (NPWT) with conventional gauze dressings in traumatic soft-tissue injury at a tertiary care centre. Methods: A prospective control study was conducted between September 2012 and November 2014. Patients with one or more traumatic soft-tissue injuries with contaminated wounds were allocated to either a test group (received NPWT) or control group (received conventional gauze). Wounds were assessed by two orthopaedic surgeons. If grade A was achieved, the wound was covered with split-thickness skin graft, flap or delayed primary closure; otherwise, revision debridement and NPWT/saline gauze dressings were applied. Descriptive statistics (mean, standard deviation and proportions) were used to summarise the study variables. The 95% confidence intervals (CI) for difference of mean were used. Chi-square test and Fisher's exact test were used to observe an association between the qualitative data and outcome variables. Unpaired T-Test and Mann–Whitney U test were used for analysis of the quantitative data. A pResults: A total of 104 patients were included. The mean number of dressings per patient was significantly lower in the NPWT group (3.4) than in the control group (20.7) (pConclusion: NPWT has a role in healing traumatic wounds and can be delivered effectively through hospital suction NPWT, which can also reduce the cost of therapy. We recommend its regular use in all patients presenting with post-traumatic, soft-tissue injuries when primary coverage is not possible.

Purpose Tibial fracture is the most common long bone fracture. Distal third tibial fractures are challenging though open reduction and plating can result in anatomical reduction and rigid fixation. This paper aimed to evaluate and compare the results of medial and lateral locking compression plates for distal third tibial fractures. Methods This prospective clinical study involved 36 patients with distal tibial fractures admitted in Department of Orthopaedics, Sawai Mansingh Medical College & Affiliated Hospital, Jaipur, India, from June 2011 to May 2012, including 29 closed fractures and 7 open fractures at the mean age of 38.9 years. Thirty-six patients were divided equally into two groups based on treatment method, including medial plating group (18 patients) and lateral plating group (18 patients). They were followed up for at least 5 months after discharge. The functional outcomes were evaluated using Tenny and Wiss clinical assessment criteria. Results Malunion was found in 3 cases of medial plating group and in 1 case of lateral plating group. In the medial plating group, there were 5 cases of superficial infections, 1 deep infection, 1 nonunion and 3 wound dehiscence. In the lateral plating group, there was 1 case of superficial infections, 1 deep infection and 1 nonunion. In the lateral plating group, 4 patients reported feeling the plates and screws but none of them asked to remove the hardware. In the medial plating group, 9 patients reported symptomatic hardware problems and 7 asked to remove the hardware. The number of cases graded as excellent/good/fair was 1/8/7 in the medial plating group and 3/7/7 in the lateral plating group respectively. In the medial plating group, the final range of motion was 17.2° in ankle dorsiflexion and 30.7° in ankle plantar flexion. In the lateral plating group, the final range of motion was 19° in ankle dorsiflexion and 34.2° in ankle plantar flexion. Conclusion Lateral plating of distal tibia is safe and feasible, which can provide biological fixation and prevent the soft tissue complications associated with medial plating.

Nuclear safety not only depends on the reliability and safety of the structures, systems, and components (SSCs) but also largely depends on human factors and interaction of operators with machines. Simulators greatly support in the training and transfer of knowledge to the plant operators. This paper shares an experience in indigenous development of full scope, non-replica simulator for a more than 30 years old, 100 MW research reactor at BARC Trombay. The simulator was so designed that over and above training of the plant personnel, it will be used for safety studies in the area of reactor physics and thermal hydraulics. The interface was designed to support the interaction of the operators with the simulator through virtual panels supported by touch screens with high-fidelity graphic displays. Important postulated initiating events (PIEs) like loss of offsite power, loss of coolant accident, loss of regulation incident, etc. have been modeled. This information will provide an insight to verify and validate the plant emergency operating procedures (EOPs). The simulator will also be used for the development of human factor models as well as the design of future visual display unit (VDU)-based control rooms. This will also enable the operators to align themselves from the traditional panel-based human–machine interface (HMI) to personal computers.

Background Tibia fracture is the most common long bone fracture. The fractures of tibia are commonly open fractures due to subcutaneous position of the tibia. The choice of technique for stabilization of open tibia fractures includes - External fixation, unreamed intra-medullary nails [URTN], Reamed intra-medullary nails, ORIF with Plating. Objectives To evaluate & compare the results of Unreamed Intra-Medullary Nail Versus Half Pin External Fixator in Grade III [A & B] Open tibia fractures. Methods This prospective clinical study [Randomized chit box] was done on 50 patients presenting to our institute within 24 h of injury. Only those who were skeletally mature with open tibia fracture Grade IIIA & IIIB [Gustilo-Anderson] were included in this study. After initial management, radiological assessment was done. Following this adequate wound debridement, skeletal stabilization with either primary URTN or external fixator was done. Inspection and debridement were repeated at 48-h intervals until the wound was considered clean. Results 50 cases [25 each group] were compared in terms of - Final Alignment of the Fracture, Presence of Infection/Non-union/Mal-union, Hardware failure, Time to Bone Union, Number of Operative Procedures after index admission. Mean time to full weight bearing was 20.96 weeks in URTN group versus 24.8 weeks in Ex-fix group. 5 in URTN group required further surgery for non-union versus 11 patients in Ex-fix group. There were 6 significant pin track infection. Removal of nail was required in 1 case of deep infection. Conclusion This study supports the use of the URTN over External fixator in the treatment of severe open tibia fractures.

The loudness of broadband sound is often modeled as a linear sum of specific loudness across frequency bands. In contrast, recent studies using molecular psychophysical methods suggest that low and high frequency components contribute more to the overall loudness than mid frequencies. In a series of experiments, the contribution of individual components to the overall loudness of a tone complex was assessed using the molecular psychophysical method as well as a loudness matching task. The stimuli were two spectrally overlapping ten-tone complexes with two equivalent rectangular bandwidth spacing between the tones, making it possible to separate effects of relative and absolute frequency. The lowest frequency components of the “low-frequency” and the “high-frequency” complexes were 208 and 808 Hz, respectively. Perceptual-weights data showed emphasis on lowest and highest frequencies of both the complexes, suggesting spectral-edge related effects. Loudness matching data in the same listeners confirmed the greater contribution of low and high frequency components to the overall loudness of the ten-tone complexes. Masked detection thresholds of the individual components within the tone complex were not correlated with perceptual weights. The results show that perceptual weights provide reliable behavioral correlates of relative contributions of the individual frequency components to overall loudness of broadband sounds.

Different computational models have been developed to study the interaural time difference (ITD) perception. However, only few have used a physiologically inspired architecture to study ITD discrimination. Furthermore, they do not include aspects of hearing impairment. In this work, a framework was developed to predict ITD thresholds in listeners with normal and impaired hearing. It combines the physiologically inspired model of the auditory periphery proposed by Zilany, Bruce, Nelson, and Carney [(2009). J. Acoust. Soc. Am. 126(5), 2390–2412] as a front end with a coincidence detection stage and a neurometric decision device as a back end. It was validated by comparing its predictions against behavioral data for narrowband stimuli from literature. The framework is able to model ITD discrimination of normal-hearing and hearing-impaired listeners at a group level. Additionally, it was used to explore the effect of different proportions of outer- and inner-hair cell impairment on ITD discrimination. ispartof: JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA vol:144 issue:2 pages:940-954 ispartof: location:United States status: Published online

The sense of taste allows animals to sample chemicals in the environment prior to ingestion. Of the five basic tastes, sour, the taste of acids, had remained among the most mysterious. Acids are detected by Type III taste receptor cells (TRCs), located in taste buds across the tongue and palate epithelium. The first step in sour taste transduction is believed to be entry of protons into the cell cytosol, which leads to cytosolic acidification and the generation of action potentials. The proton-selective ion channel Otop1 is expressed in Type III TRCs and is a candidate sour receptor. Here, we tested the contribution of Otop1 to taste cell and gustatory nerve responses to acids in mice in which Otop1 was genetically inactivated (Otop1-KO). We first show that Otop1 is required for the inward proton current in Type III TRCs from different parts of the tongue that are otherwise molecularly heterogeneous. We next show that in Type III TRCs from Otop1-KO mice, intracellular pH does not track with extracellular pH and moderately acidic stimuli do not elicit trains of action potentials, as they do in Type III TRCs from wildtype mice. Moreover, gustatory nerve responses in Otop1-KO mice were severely and selectively attenuated for acidic stimuli, including citric acid and HCl. These results establish that the Otop1 proton channel plays an important role in acid detection in the context of the mouse gustatory system, evidence that it is a bona fide sour taste receptor.

A computational model of cat auditory nerve fiber (ANF) responses to electrical stimulation is presented. The model assumes that (1) there exist at least two sites of spike generation along the ANF and (2) both an anodic (positive) and a cathodic (negative) charge in isolation can evoke a spike. A single ANF is modeled as a network of two exponential integrate-and-fire point-neuron models, referred to as peripheral and central axons of the ANF. The peripheral axon is excited by the cathodic charge, inhibited by the anodic charge, and exhibits longer spike latencies than the central axon; the central axon is excited by the anodic charge, inhibited by the cathodic charge, and exhibits shorter spike latencies than the peripheral axon. The model also includes subthreshold and suprathreshold adaptive feedback loops which continuously modify the membrane potential and can account for effects of facilitation, accommodation, refractoriness, and spike-rate adaptation in ANF. Although the model is parameterized using data for either single or paired pulse stimulation with monophasic rectangular pulses, it correctly predicts effects of various stimulus pulse shapes, stimulation pulse rates, and level on the neural response statistics. The model may serve as a framework to explore the effects of different stimulus parameters on psychophysical performance measured in cochlear implant listeners.

Catalytic hydrodeoxygenation of 4-propylguaiacol, a model compound for lignin-derived components of pyrolysis oil, was performed in a packed-bed microreactor. The effects of various processing cond...

Acetic acid was used as a model compound for pyrolysis oil in a hydrodeoxygenation (HDO) study. HDO of acetic acid was performed in a packed bed microreactor. The catalyst was reduced sulfided NiMo/Al2O3. The effects of state of aggregation of acetic acid, temperature, hydrogen partial pressure, liquid flow rate, reactor diameter, and residence time on conversion, yield, space-time consumption, and space-time yield were investigated. External and internal mass transfer and heat transfer resistances were also examined in the microreactor. Temperature was a major factor in HDO of acetic acid. Many consider hydrodeoxygenation as an unattractive process due to high pressure requirements (1050–3000 psig). In this work, attempt has been made to show that HDO of acetic acid can be conducted at atmospheric pressure with a significant conversion achieved. More acetic acid was converted during HDO as temperature was increased at constant pressure of 300 psig. Conversion was much higher for vapor phase acetic acid at atmospheric pressure than liquid phase acetic acid. HDO of gas phase acetic acid in a blank reactor compared to a catalytic HDO showed that thermal decomposition of acetic acid did not occur appreciably. Partial pressure of hydrogen above 240 psig had no effect on the conversion of liquid phase acetic acid. Conversion of vapor phase acetic acid increased as the partial pressure of hydrogen increased from 3 psig to 15 psig. Residence time was 0.06 s for a maximum conversion of liquid phase acetic acid, whereas it was 0.03 s for a maximum conversion of vapor phase acetic acid. The conversion of acetic acid for both liquid and vapor phases decreases significantly as the flow rate of acetic acid increases. As reactor diameter increases beyond 0.8 mm, the conversion reduces significantly. Mass transfer resistance was negligible at the superficial velocity of 2.54 m/s and at an average catalyst particle size of 113 μm. Radial temperature difference in the microreactor was less than 5%.

Background Biodegradable devices have been developed to overcome the disadvantages of metallic implants especially the need for their subsequent removal, though they have their own drawbacks like poor mechanical properties and tissue reactions. Aim of this prospective study was to access the outcome of bimalleolar fractures fixed with biodegradable plates and screws. Methods A prospective study was conducted between July 2006 and November 2008 comprising of sixteen patients with unilateral bimalleolar fractures. Fibula fractures were fixed with biodegradable plates and medial malleoli with screws. Patients were followed at two weeks, six weeks, three months, six months, twelve months and eighteen months. Final evaluation was done using Olerud Molander ankle score. Results Six patients had excellent results; four patients had good results and six patients had fair performance. No patient in this series had a poor outcome. One patient had both pain and swelling at 14 weeks postoperatively which settled down with debridement and antibiotics. None of the patients needed implant removal. Conclusion Biodegradable plates and screws when used to fix bimalleolar fracture along with restricted weight bearing, provide satisfactory fracture healing, good functional results and reduce the need of implant removal.

Hip reconstruction with subtrochanteric valgus extension pelvic support osteotomy and distal femoral osteotomy for lengthening and varus correction is one of the options available for salvage of chronic unstable hips and is also known as Ilizarov hip reconstruction (IHR). This study evaluated the outcomes and complications associated with IHR in skeletally mature young patients. Twelve patients (7 males, 5 females) with a mean age of 23 years underwent IHR for chronically dislocated hips due to various causes. Preoperative clinical and radiological evaluations were used to determine the site of osteotomies and the required angulations. Postoperatively the patients were followed up clinically and radiologically for a minimum of 36 months. Ilizarov fixator was removed when adequate lengthening was achieved and there was radiological evidence of union. Harris Hip Score was used to document hip function preoperatively and at final evaluation. Significant improvements occurred in limb length discrepancy (LLD) 5.11 cm preoperatively to 0.9 cm at final evaluation, Harris Hip Score 44.33 points preoperatively to 70.83 points (p

At least two sites of spike generation are observed in the electrically stimulated auditory nerve, namely, the peripheral axon and the central axon. The peripheral axon responds to the cathodic charge and the central axon to the anodic charge with an approximate spike-latency difference of 200 μs. The peripheral axon also shows longer refractory periods than the central axon. In this study, a phenomenological model of the electrically stimulated auditory nerve described in Joshi et al. [JARO 18(2), pp. 323–342] was used to understand the effect of spike generation sites on the temporal coding. Modulation detection thresholds for different carrier pulse rates were predicted from simulated responses of the auditory nerve, and refractoriness of both the axons was varied to test its effect on temporal coding. The results show that an increase in pulse rate increased the number of spikes generated at the central axon, hence decreasing the modulation detection thresholds. Refractoriness also played a crucial ro...

Open fractures with bone loss are a common occurrence following high energy trauma. But usually the bone fragments are lost on the roadside and are not usable. We report a patient who was involved in a head-on collision between two wheelers and presented with a bone fragment embedded in his thigh. Radiological survey revealed no bony injury in that patient. Another patient, who presented at the same time, sustained a segmental fracture of shaft femur and was found to have lost a bone fragment that was similar to the one found in previous patient. CT scan with 3D reconstruction revealed this missing fragment to be the same as that found in previous patient. Both patients had a history of head-on collision while travelling on a two-wheeler. Present case report throws some highlights on the probable mechanism of injury.

Several studies have shown that normal hearing (NH) listeners place greater weight on the edge frequencies of broadband sounds when they are asked to pick the louder of two intervals in a sample discrimination task. However, little is known about the effects of hearing loss on spectral weighting for broadband sounds. In a classic study of sample discrimination, Doherty and Lutfi (1996) found that listeners with hearing loss (HL) placed greater weight on frequencies in the region of the HL and proposed that components that were less audible were weighted higher. The current study investigated the effect of audibility and hearing loss on spectral weighting for loudness judgments using two spectrally overlapping 18-tone complexes (from 208- to 8708-Hz). Four NH and nine HL listeners judged the loudness of tone complexes in two conditions where the mean level of each tone in the complex was set to either 10-dB SL or 75-dB SPL. The results show that listeners placed greater weight on the high-frequency edges o...

An important ability of the auditory system is to localize sound sources in complex acoustical environments. Two important cues for localization are interaural time- and level differences (ITD, ILD). The sensitivity to these cues differs across frequency and has previously been estimated through frequency-specific detection thresholds. Detection thresholds of ITDs/ILDs are, however, affected by stimulus energy in remote spectral regions, referred to as binaural interference. In this study, the spectral weights of ITD- and ILD cues in the lateralization of a broadband signal was investigated using regression analysis. The stimuli consisted of eleven 1-ERB-wide noise bands (442 Hz-5544 Hz) containing ITD or ILD cues. In experiment 1, ITDs or ILDs were applied to the noise bands and roved independently on every trial. In experiment 2, the noise bands centred at 442 Hz and 5544 Hz were removed to investigate the effect of stimulus bandwidth. In experiment 3, the same two noise bands were present, but containe...

The temporal order discrimination of target tone pairs is hindered by the presence of flanker tones but is improved when the flanker tones are captured by a separate stream of tones that match the flankers in frequency [Bregman and Rudnicky (1975). J. Exp. Psychol. 1, 263–267]. In an event-related potential (ERP) study with these stimuli, listeners' mismatch negativity (MMN) responses were temporally linked to the position of the changing target tones, irrespective of streaming. In contrast, N1 response latency varied as a function of the perceived grouping of flanker tones established by previous behavioral studies, providing a neurophysiological index of auditory stream segregation.

Subjects with normal hearing (NH) and with sensorineural hearing loss (SNHL) judged the overall loudness of six-tone complexes comprised of octave frequencies from 0.25 to 8 kHz. The level of each tone was selected from a normal distribution with a standard deviation of 5 dB, and subjects judged which of two complexes was louder. Overall level varied across conditions. In the “loudness” task, there was no difference in mean level across the two stimuli. In the “sample discrimination” task, the two complexes differed by an average of 5 dB. For both tasks, perceptual weights were derived by correlating the differences in level between matched-frequency tones in the complexes and the loudness decision on each trial. Weights obtained in the two tasks showed similar shifts from low to high frequency components with increasing overall level. Simulation of these experiments using a model of loudness perception [Moore and Glasberg (2004), Hear Res. 188, 70–88] yielded predicted weights for these stimuli that were highly correlated with predicted specific loudness, but not with the observed weights.

A primary demyelinating form of experimental allergic encephalomyelitis (EAE) resembling human multiple sclerosis (MS) occurs in Callithrix jacchus marmosets following immunization with human white matter. Participation of a T-cell immune response against myelin basic protein (MBP) in this disease model is supported by observations of increased reactivity against MBP in PBMC and of adoptive transfer of an inflammatory form of EAE by MBP-reactive T-cells. To evaluate the effects of ectopic presentation of MBP on marmoset EAE, animals were vaccinated prior to induction of EAE by subcutaneous injection of attenuated strains of vaccinia virus genetically engineered to contain either the entire coding sequence for human MBP (vT15) or the equine herpes virus glycoprotein gH gene (vAbT249). Vaccination with vT15 was followed by transient cytoplasmic and surface membrane expression of MBP in circulating PBMC (15–45 days). The onset of clinical EAE after immunization (pi) was markedly delayed in vT15-vaccinated animals (37–97 days pi, n =4) compared to vAbT249-vaccinated controls (14–18 days pi, n =3). Proliferative responses against MBP but not against vaccinia antigens or phytohemagglutinin were suppressed in protected animals. Thus, development of attenuated live viruses carrying genes for myelin antigens could be useful for induction of immunologic tolerance and for modulation of autoimmune demyelination.

The current study measured the additional masking obtained for combinations of forward and simultaneous maskers as a function of forward masker bandwidth, signal delay, and simultaneous masker level. The effects of the two individual maskers were equated in all conditions. Additional masking increased with increasing masker level, increasing signal delay, and decreasing masker bandwidth. The portion of the simultaneous masker that made the greater contribution to additional masking was the part that overlapped with the signal, not with the forward masker. The changes in additional masking observed as a function of forward masker bandwidth and the interaction between the effects of forward and simultaneous maskers call into question the use of additional masking as a measure of basilar membrane compression and present problems for the use of simultaneous noise to simulate hearing loss.

CIs stimulate the auditory nerve fibers (ANF) with a train of amplitude modulated current pulses. Depending on polarity, the pulses can generate spikes at different sites along the ANF. The latency difference between spikes generated at the central and the peripheral axons was found to be up to 200 μs in cats and up to 450 μs in humans. These timing differences could be the reason underlying the poor performance of CI listeners in ITD perception. A model of ANF responses to electrical stimulation (Joshi et al., 2016), which includes two sites of spike generation along the ANF was used to simulate the ANF responses to constant-amplitude and modulated pulse trains for different pulse-rates. The fidelity of the temporal coding was quantified by calculating the phase-locking value. The results show that an increase in pulse-rate leads to higher uncertainty in the site of spike generation, reduction in phase-locking, and increase in variance of its distribution. This may account for impaired ITD thresholds obs...

Introduction Subtrochanteric fractures are difficult fractures associated with high incidence of complications and various implants, both intramedullary and extramedullary, are available for their fixation. Traditional extramedullary implants are associated with higher rate of implant failure and varus collapse while the biomechanically better intramedullary nails are technically demanding and are associated with higher re-operation rates. This study was done to evaluate the outcome following biological (indirect) fixation of unstable comminuted subtrochanteric fractures with proximal femur-locking compression plate (PF-LCP). Methods Thirty-five consecutive patients with comminuted subtrochanteric fractures were operated upon with PF-LCP by using an indirect reduction technique. Seinsheimer types 3–5 fractures were included in the study. Operating time, blood loss and any technical difficulty with the implant were recorded. Patients were followed clinically and radiologically for union at fracture site and implant-related complications. The Harris Hip Score was used to document hip function at final follow-up. Results Thirty-two patients with average age of 44.7 years were available for final evaluation. The mean operating time was 79.5 min and total blood loss averaged 233.13 ml. Union was achieved in all cases with an average time of 15.62 weeks. Complications included two cases of delayed union and two cases of infection. Two cases had a shortening of 1 cm and one case had malunion with external rotation. No instances of implant failure or nonunion were recorded. Conclusion Biological fixation of comminuted subtrochanteric fractures with PF-LCP provides stable fixation with high union rate and fewer complications.

The influence of the environment and of the major histocompatibility complex (MHC) in shaping the human T-cell receptor beta-chain variable region (TCRBV) repertoire has not been systematically studied. Here, expression of TCRBV gene families was estimated by a sensitive polymerase chain reaction (PCR)-based method. Serial studies of peripheral blood, performed at 2-week intervals over a 3-month period, revealed that fluctuation in the expression of many TCRBV genes occurred in healthy individuals and in the absence of clinically evident infections. Fluctuation of TCRBV4, TCRBV5.2, TCRBV9, and TCRBV13.1 genes were present in all subjects. Additional TCRBV genes fluctuated in some but not in other individuals. Comparison of the TCRBV repertoire between these unrelated individuals indicated differences in the mean expression of TCRBV5.1, TCRBV9, TCRBV11, TCRBV15, TCRBV17, and TCRBV20 genes. For any TCRBV gene, intersubject differences were generally of a magnitude of twofold or less. Larger differences characterized the TCRBV repertoire of CD4 compared to CD8 cells. Some differences, for example over-representation of TCRBV2 and TCRBV5.1 on CD4, and TCRBV10, TCRBV14, and TCRBV16 on CD8 cells, were present in most subjects. Individuals homozygous for DR2- or DR3-bearing extended MHC haplotypes displayed similar individual variability of TCRBV expression. These data indicate that the circulating TCRBV repertoire in humans is both dynamic and diverse. Both environment and MHC effects contribute to the diversity of TCRBV expression.

Chronic relapsing-remitting experimental allergic encephalomyelitis (EAE) was induced in cynomolgus monkeys by a single immunization with a homogenate of human brain white matter (BH) in adjuvant. Proliferative T lymphocyte responses to BH, to myelin basic protein (MBP), but not to proteolipid protein, were detected in peripheral blood mononuclear cells (PBMC) of all animals and persisted until their death or, in surviving animals, for greater than 10 mo postimmunization. Responses of higher magnitude tended to be associated with fatal, compared with nonfatal, episodes of clinical EAE. The frequency of MBP-reactive T cells in PBMC of animals with acute EAE was quantitated with a soft agar colony system; the ratio of T cells that proliferated specifically to MBP was estimated at between 5 and 20 per 10(6) PBMC. A similar frequency of peptide-specific T cells was estimated from PBMC of monkeys immunized with a synthetic 14-mer peptide corresponding to a region near the carboxy terminus of MBP. Thus, autoantigen-reactive T cells can be detected in the circulation throughout the course of chronic EAE, are predictive of disease severity, and occur at a frequency similar to that estimated to be present in humans with multiple sclerosis.

Although tyrosine-azobenzenearsonate (ABA-Tyr) is not degraded by proteolytic enzymes, its presentation by accessory cells is inhibited by lysosomotropic agents such as chloroquine. Presentation of ABA-poly-L-glutamic, alanine, tyrosine (ABA-GAT) is similarly inhibited by chloroquine, but in contrast to ABA-Tyr it is also inhibited by leupeptin. Finally formaldehyde fixation of accessory cells after pulsing with ABA-Tyr but not before permits successful stimulation of ABA-specific hybridoma cells. These results suggest that a lysosomal pathway but not digestion is necessary for the association of ABA-Tyr and la molecules for presentation.

Weighting patterns for loudness obtained using the reverse correlation method are thought to reveal the relative contributions of different frequency regions to total loudness, the equivalent of specific loudness. Current models of loudness assume that specific loudness is determined by peripheral processes such as compression and masking. Here we test this hypothesis using 20-tone harmonic complexes (200Hz f0, 200 to 4000Hz, 250 ms, 65 dB/Component) added in opposite phase relationships (Schroeder positive and negative). Due to the varying degree of envelope modulations, these time-reversed harmonic complexes have been shown to produce different outputs at the basilar membrane and different amounts of forward and simultaneous masking. The perceptual weights for loudness did not differ for these two complexes. To determine whether the level rove introduced to obtain weights had changed the fundamental differences in the stimuli, a similar level rove (±8 dB) was introduced on each component of Schroeder positive and negative forward maskers. The Schroder negative maskers continued to be more effective. These results suggest that perceptual weights for loudness are not completely determined by peripheral processes and reflect a central frequency weighting template. [Work supported by NIH R01 DC011806 and P30 DC004662.]

Indirect evidence suggests that an autoimmune response to myelin basic protein (MBP) may be involved in the pathogenesis of multiple sclerosis (MS). In MS, several reports have suggested that restricted T-cell populations respond to MPB, as in inbred rodents with the MS disease model experimental allergic encephalomyelitis. In experimental allergic encephalomyelitis, the T-cell repertoire to MBP varies between strains, and in MS it is likely that the response to MBP is also best defined under conditions where genetic differences between subjects are controlled. In this report, the fine specificity of the T-cell response to MBP was assessed in three families, each with multiple individuals affected with MS. We found that (1) comparable frequencies of MBP-reactive T-cell lines were obtained from peripheral blood of MS patients and their healthy siblings. Human leukocyte antigen (HLA) identical sibling pairs discordant for MS had similar frequencies of MBP-reactive T-cell lines. (2) A broad spectrum of MBP epitopes was recognized by T-cell lines from all individuals studied. Within a family, the fine specificity of MBP recognition showed little or no overlap between individuals, even between HLA identical siblings. (3) Recognition of MBP epitopes occurred in the context of different HLA class II alleles. At least four DR alleles each served as restricting elements for recognition of P82-101 or the carboxy terminal region of MBP, two regions thought to be important in the human T-cell response to the molecule. No relationship between the use of a particular DR allele and a response to a particular region of MBP could be established.(ABSTRACT TRUNCATED AT 250 WORDS)

A contribution of allelic variation of T-cell receptor (Tcr) genes to the immune response has not been studied. Here we report that the presence of insertion-deletion-related polymorphisms (IDRP) of the Tcr beta chain (Tcrb) can be utilized to distinguish the parental origin of the gene complex that undergoes rearrangement in individual T-cell clones. Phytohemagglutinin stimulated clones from an individual heterozygous for an IDRP located between the variable (V) and diversity (D)-joining (J) region genes were studied for the presence of V to DJ rearrangements in each of the two parental chromosomes. Results indicate that single rearrangements were present in the majority of clones, in contrast to the double rearrangements of D to J genes that were generally present. In this individual, V to DJ rearrangement also occurred with different frequencies on each of the two germline genes. IDRP clonotyping of the Tcrb complex should prove generally applicable to the study of the influence of allelic variation of Tcrb genes in selection of the expressed T-cell repertoire.

Background: Ununited fracture neck of femur in young adults has been tackled in various ways. Methods: Twenty five patients of ununited fracture neck of femur in age group 21-55 years were treated by closed reduction, cancellous screw fixation and fibular strut graft and followed up for 2-6 years. Time gap between injury and operation was 6 weeks to 58 weeks. Five cases were previously fixed with various fixation devices. Results: Osseous union was achieved in 24 cases with average time of 18.16 weeks. Main complication encountered in follow-up was avascular necrosis of femoral head, others were joint stiffness and shortening. Functional end results were good to excellent in 24 cases. Conclusion: Closed reduction with internal fixation by cancellous screw and fibular strut grafting is easy and useful procedure.