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The objective of this systematic review is to determine the fate of spinal implants when patients develop postoperative wound infection after posterior instrumental fusion in a degenerative spine.A systematic review of the English-language literature (published between January 2001 and July 2020) was undertaken to identify articles documenting the management strategy for surgical site infections (SSIs) after posterior lumbar spinal fusion. Studies on pedicle screw fixation after trauma, immunocompromised, metastatic spine disease, and combined anterior/posterior approach were excluded. Two independent reviewers assessed the level of evidence quality using the criteria set by the North American Spine Society, and disagreements were resolved by consensus.Of the 3071 citations identified, 49 met the criteria to undergo full-text review. Outcomes after SSIs were studied from a combined pool of 1150 patients who had undergone instrumental spinal fusion. The collected data showed that 456 patients (39.97%) had undergone spinal implant removal after SSI while 694 patients (60.03%) had their implants retained until the resolution of SSI. There was an absolute risk reduction (ARR) of 29% (-0.292) and a relative risk reduction (RRR) of 50.3% (-0.503) of implant removal if the patient underwent wound debridement following SSI. The number needed to treat (NNT) for wound debridement was calculated at 3.31 from our pooled cohort. The ARR in implant removal following vacuum-assisted closure (VAC) therapy was 16.6% and RRR was noted at 40.4%. This led to a high value of NNT at 6.0 patients. There was an ARR of 33.5% and a RRR of 70.7% was estimated in patients undergoing continuous irrigation.Our review of the literature suggests that surgeons prefer early wound debridement with or without negative pressure wound therapy under antimicrobial coverage for eradication of SSI after posterior lumbar spinal fusion. Implant removal is generally reserved for cases refractory to the other treatment modalities.

Redundant Nerve Roots (RNR) is a common radiological observation of elongated tortuous appearance of cauda equina nerve roots in sagittal MRI. It is considered a poor prognostic factor, but the associated spinal morphometry remains unfamiliar.A retrospective cohort study was conducted at the Aga Khan University Hospital, Pakistan. Patients, aged 18 or above, undergoing decompressive spinal surgery due to degenerative Lumbar Spinal Canal Stenosis (LSCS) in 2015 were included. Patients were divided in groups as per presence of RNR and assessed for spinal morphometric parameters.Fifty-two patients, aged 57.52 ± 12.08 years, were enrolled in the study. The patients in RNR group were older than those in non-RNR group (p = 0.023). RNR was significantly associated with sedimentation sign (15 vs 11; p = 0.011), as well as L2/L3 (12 vs 9; p = 0.043) and L3/L4 (18 vs 18; p = 0.034) stenosis. Ligamentum flavum hypertrophy at the most stenotic level was more common in the RNR group (20 vs 19; p = 0.006). The only quantitative parameter statistically associated with RNR was lower ligamentous interfacet distance (5.07 ± 1.95 vs 8.07 ± 4.26 mm; p = 0.010). All other parameters did not contribute to the development of RNR in LSCS patients. The multivariate model revealed significant contribution of age, male sex, ligamentous interfacet distance and disc bulge to develop RNR.Certain spinal morphometric parameters contribute towards RNR formation, which represents higher degree of spinal stenosis. These parameters, along with RNR, should be regularly reported for preoperative consideration of LSCS management.

Some CO2-reducing technologies have real-world benefits not captured by regulatory testing methods. This paper documents a two-layer heating, ventilation, and air-conditioning (HVAC) system that facilitates faster engine warmup through strategic increased air recirculation. The performance of this technology was assessed on a 2020 Hyundai Sonata. Empirical performance of the technology was obtained through dynamometer tests at Argonne National Laboratory. Performance of the vehicle across multiple cycles and cell ambient temperatures with the two-layer technology active and inactive indicated fuel consumption reduction in nearly all cases. A thermally sensitive powertrain model, the National Renewable Energy Laboratory’s FASTSim Hot, was calibrated and validated against vehicle testing data. The developed model included the engine, cabin, and HVAC system controls. Validation of component thermal models and engine efficiency ensured accurate thermal dynamics, fuel consumption, and two-layer benefit. The real-world benefit of the two-layer technology was calculated by simulating the validated powertrain model across a representative test matrix comparing performance with and without the two-layer system. Simulation across the test matrix revealed a real-world representative benefit of 0.0835%. Analysis of test matrix results at the regional level revealed the most benefit in cold climates and rural regions. Mean results across cycle length sensitivity simulations revealed a larger real-world benefit of 0.0872%. These benefit values can be considered a more accurate assessment of real-world technology performance. Future work is planned to explore the requisite number of drive cycles to ensure the full technology benefit is captured.

Objective: To compare NIH funding in the field of Otolaryngology to other medical and surgical specialties between 2009 and 2019. Methods: Data was collected from the NIH RePORTER database on funding dollars received by each specialty from 2009 to 2019. Along with data on total active physicians per specialty using the Physician Specialty Data Book, comparisons were drawn between Otolaryngology and other medical and surgical specialties with regards to trends in total funding and NIH funding dollars per physician. The distributions of grant funding, within Otolaryngology from various NIH institutes among principal investigators, organizations, and subspecialties were further explored. Results: There were 3810 grants (1147 unique projects) for a total of $1 276 198 555 funded by the NIH to Otolaryngology departments from 2009 to 2019. Statistically insignificant funding increases ( P > .05) caused otolaryngology to fall from first to fourth in funding among studied specialties. The National Institute on Deafness and Other Communication Disorders funded 57% of all unique projects, and 57.2% of all unique NIH projects were otology related. Most projects were basic science related. The top 10 principal investigators obtained 22.3% of the total NIH funding for Otolaryngology. The top 3 organizations over the studied period comprised 26.55% of the total funding, generating a combined 729 grants. Among principal investigators, 63.0% had a PhD degree, 25.3% had an MD, and 9.6% had an MD/PhD. Conclusion and Relevance: NIH funding in Otolaryngology has remained stable and is highly concentrated among a small number of organizations, geographic regions, and principal investigators. Recent initiatives by academic communities have sought to address funding disparities by incorporating diversity and inclusion into clinician-scientist pipelines. We urge our colleagues to strive toward identification of the factors that contribute to successful acquisition of funding and implementation of a more conducive institutional infrastructure to produce research.

Hodgkin lymphoma (HL) patients who relapse after autologous-stem-cell- transplantation (auto-SCT) have traditionally had a poor prognosis. We analyzed 1781 adult HL patients who relapsed between 2006 and 2017 after a first auto-SCT. The 4-year overall survival (OS) after relapse continuously increased from 32% for patients relapsing in 2006-2008, to 63% for patients relapsing in 2015-2017 (p = 0.001). The improvement over time was predominantly noted in patients who had an early relapse (within 12 months) after auto-SCT (p = 0.01). On multivariate analysis, patients who relapsed in more recent years and those with a longer interval from transplant to relapse had a better OS, whereas increasing age, poor performance status, bulky disease, extranodal disease and presence of B symptoms at relapse were associated with a worse OS. Brentuximab vedotin (BV), checkpoint inhibitors (CPI) and second transplant (SCT2; 86% allogeneic) were used in 233, 91 and 330 patients respectively. The 4-year OS from BV, CPI, and SCT2 use was 55%, 48% and 55% respectively. In conclusion, the outcome after post-transplant relapse has improved significantly in recent years, particularly in the case of early relapse. These large-scale real-world data can serve as benchmark for future studies in this setting.

Introduction After high dose chemotherapy (HDC) and autologous stem cell transplantation (auto-SCT), in patients with relapsed/refractory diffuse large B cell lymphoma (DLBCL) and Hodgkin lymphoma (HL), involved field radiation therapy (RT) for consolidation and residual/progressive disease (PD) eradication is a common practice. Materials and methods Retrospective single-institution cohort analysis to evaluate the impact of early RT after HDC auto-SCT. Results Between 1996 and October 2019, 153 patients (43 DLBCL, 110 HL) underwent RT after HDC auto-SCT. Males 95 (62%), females 58 (38%), median age 24 years. Indications for RT was consolidation 65%: residual disease eradication 16%: and PD eradication 19%. For DLBCL, the median overall survival (OS) for the above indications was not reached (NR):NR:2 months and the KM 5-year OS was 72.6%:64.3%:12.5% respectively (P ≤ .000). Pair-wise analysis showed that consolidation versus residual disease eradication had no difference (P = .88) but both were superior to PD disease eradication (P ≤ 000 and P = .005 respectively). For HL, indication for RT was, 54%:23%:24% respectively. The median OS was NR:NR:28.8 months and KM 5-year OS was 82.3%:78%:30% respectively (P ≤ .000). Pair-wise analysis showed that consolidation versus residual disease eradication had no difference (P = .98) but both were superior to the PD eradication group (P ≤ 000). RT was well tolerated with no significant long-term toxicity. Conclusion Post HDC auto-SCT RT was well tolerated. DLBCL and HL patients with residual disease treated with the RT had similar long-term survival as those who received RT for consolidation. RT failed to improve the poor survival in patients with post-HDC auto-SCT PD.

Objective This article compares the outcomes of patients with traumatic acute subdural hemorrhage (SDH) managed either with craniotomy (CO) or with decompressive craniectomy (DC). Methods In this single-center, retrospective analysis we included all adult patients with acute traumatic SDH who were treated either using CO or DC. Sixteen-year hospital data was reviewed for patient demographics, injury details, and hospital course. Outcomes were noted in terms of intraoperative blood loss, intensive care unit stay, need for tracheostomy, post-surgery Glasgow Coma Score (GCS; calculated immediately after surgery), delayed GCS (DGCS; calculated 1 week after surgery), and delayed Glasgow Outcome Score (DGOS) after 6 months of surgery. Postoperative complications were noted during hospital stay, while mortality was noted within 6 months of surgery for each patient. Results Patients who underwent DC were younger (mean age 34.4 ± 16.8 years vs. 42.4 ± 19.9 years in the CO group) (p = 0.006). Patients who underwent DC also had worst degree of traumatic brain injury as per Marshall grade (62.4% patients with Marshall grade 4 in the DC group vs. only 41.2% patients in the CO group) (p = 0.037). Mean size of hematoma was 23.8 ± 24.6 mm in the DC group versus 11.3 ± 8.2 mm in the CO group (p = 0.001). Mean postop GCS was lower in the DC group; 8.0 ± 4 versus 10.8 ± 4 in the CO group (p Conclusion The patients who underwent DC were younger, had larger size hematoma, and poor Marshall grade. We did not find any significant difference in the outcomes of CO and DC for management of subdural hematoma.

Saudi Arabia is the largest of the Arabian Gulf countries with a total population of 33.41 million as of 2017. This report summarizes the experience from four leading tertiary care hematopoietic stem cell transplantation (HSCT) centers in Saudi Arabia representing more than 90% of all HSCTs performed in the country. Between 1984 and 2016, a total of 6,184 HSCTs were performed. Of these, 3,586 HSCTs were performed in adults and 2,598 HSCTs were performed in pediatric patients. Malignancy was the main indication for transplantation (47%). While most transplants were performed from an identical sibling donor, HSCTs from cord blood, unrelated and, more recently, haploidentical donors have also been performed. Relative shortage of HSCT bed capacity is perceived to be a limiting factor in Saudi Arabia. Lately, more HSCT centers are emerging with rapid growth, which may significantly improve the access to HSCT in the country in the near future.

With the ever-increasing engineering and biological applications of rapid droplet solidification on superhydrophobic surfaces, developing accurate dendritic growth models has become vital at lower ...

Hodgkin lymphoma (HL) involving the Waldeyer's ring (WR) and other extranodal head and neck sites are rare. We report our experience and PubMed literature review.Retrospective single institution cohort study using lymphoma data base and PubMed literature search using twenty-six various search terms.Twenty-nine patients were treated in our institution (1975-2018). Male:Female 22:7, median age at diagnosis 33 years (15-64), stages I-II:III-IV 25:4. Sites were nasopharynx (10), tonsil (9), parotid (5), mandible (2) and others (3). 20/29 patients received radiation therapy, 22/29 received chemotherapy. Ten years overall-survival and progression-free survival are 92% and 66% respectively. PubMed search showed 8766 citations and identified 357 patients including our patients. Male:Female 199:131, median age 45 years (5-89). Stages I-II in 286 (80%). Involvement was nasopharynx 109 (30.5%), tonsil 67 (18.8%), parotid 58 (16.2%), thyroid 45 (12.6%), adenoid 10 (2.8%), mandible 10 (2.8%) and others in 58 (16.2%). Pathology: mixed cellularity 99 (27.7%), nodular sclerosis 88 (24.6%), nodular lymphocyte-predominant 56 (15.7%), lymphocyte rich 25 (7%), classical-HL-not otherwise specified 16 (4.5%) and lymphocyte depleted 7 (2%) patients. Treatment details are available for 233 patients; 165 (46%) received radiation therapy, 137 (38%) chemotherapy. Complete remission in 208 (58%), progressive disease 14 (4%), no information 135 (38%). Overall, treatment failure in 54 (15%). Thirty (8.4%) have died; 21 disease related. KM overall-survival at 5 and 10 years was 88.5% and 77.6% respectively.This largest report showed that HL involving extranodal head and neck sites is not very uncommon and has excellent prognosis.

Redundant Nerve Root (RNR) is a tortuous and elongated radiological appearance of cauda equina on Magnetic Resonance Imaging (MRI) in Lumbar Spinal Canal Stenosis (LSCS) patients. This study evaluated preoperative spinal morphometry associated with the development of RNR.The retrospective cohort was conducted at The Aga Khan University Hospital, and included patients undergoing decompressive spinal surgery secondary to degenerative LSCS in 2015. The patients were divided into two groups with respect to the presence of preoperative RNR. Spinal morphometry was defined by several radiological parameters, including areas of dural sac (DSA), spinal canal, spinal foramen, facets, and spinal joints, and bilateral angles based on vertebral anatomy.A total of 55 patients were enrolled with a mean age of 57.1 years, in which 22 (40%) expressed RNR in their MRI. The RNR group had significantly lower mean DSA (59.64 vs 84.01 mmRNR was associated with a higher degree of stenosis in patients with LSCS. Bilateral anterior and posterior facets angles contribute to its development, indicating particular spinal morphology to be vulnerable to the stenotic disease.

The purpose of this study was to analyze the results of second autologous hematopoietic stem cell transplantation (ASCT2) for patients with relapsed/refractory Hodgkin lymphoma (HL) after a first transplantation (ASCT1). Outcomes for 56 patients receiving an ASCT2 registered in the EBMT database were analyzed. The 4-year cumulative incidences of non-relapse mortality and disease relapse/progression were 5% and 67%, respectively. The 4-year overall survival (OS) and progression-free survival (PFS) were 62% and 28%. In univariate analysis, relapse of HL within 12 months of ASCT1 was associated with a worse OS (35% versus 76%

With growing food scarcity and high demands for vaccine storage, advancing spray freeze-drying technology has never been more important for prolonging shelf life of biological and pharmaceutical materials. Particularly, the estimation of nucleation behaviour for both pure substances and binary mixtures has become vital to the optimal thermal design and implementation of spay freeze-drying technology. Notwithstanding that past nucleation frameworks could predict nucleation rate and temperature of droplet solidification, few of them considered extreme surrounding conditions, such as very low ambient temperature below −60 degree Celsius. These environments, however, play a significant role in ascertaining the preservation and storage of chemical and pharmaceutical products, e.g., vaccines and protein drugs. It is therefore of great interest to establish accurate and reliable mathematical framework on simulating nucleation during droplet solidification subjected to ultra-cold conditions. This paper develops a semi-analytical heterogeneous nucleation model and anticipates nucleation phenomena of a suspended droplet under ultra-cold environment. Nucleation temperatures calculated from the presented model are validated against a set of experiments on single suspended droplets for a wide array of ambient temperatures from −20 until −160 degree Celsius. Both pure water and 20% w/w sucrose aqueous solution are examined for these droplets. Cumulative probability distributions of nucleation for both types of droplets over nucleation temperatures are also presented and comparisons are made between the model results and recent experimental data from literatures. Our preliminary findings demonstrate that drastic changes in nucleation temperature for ultra-cold surroundings are the aftermath of alterations in interfacial surface tension. Conventionally, the inter-facial surface tension is defined as a function of supercooling degree only, which fails as surrounding temperature is prescribed below −40 degree Celsius. In this study, the interfacial surface tension is linearly optimized using error minimization with experimental data fit, such that it substantially relates to both the supercooling degree and surrounding temperature under a given environment for pure water. As for sucrose aqueous solution (i.e., an example of binary mixtures), their solute concentration is also a dependent variable of interfacial surface tension. The results indicate that our proposed framework is capable of predicting heterogeneous nucleation in a droplet filled with either pure material or binary mixture. Development of this nucleation model for spray freeze-drying can expedite manufacturing process and reduce expenses in handling, transportation and storage of biological products, thus improving the shelf life of pharmaceuticals and availability of foods at large. Our model can be extended on other pure materials and binary mixtures, which will further be used to facilitate the design and implementation of spray freeze-drying technology for preserving and storing more chemicals and pharmaceutical excipients.

Background: Schwannomas are benign but clinically progressive tumors. Mostly, they present as intradural extramedullary lesions. They are quite rare in the intramedullary (IM) region. We report a case of IM schwannoma. Case Description: A 52-year-old gentleman presented with a history of gait instability and numbness in bilateral lower limbs. He had clinical signs of myelopathy. His magnetic resonance imaging (MRI) dorsal spine was done that showed an intradural IM lesion at the level of D11, with one differential of ependymoma. Near total resection of lesion was done and histopathology reported it schwannoma. Conclusion: Preoperative radiologic assessment for IM spinal lesions is difficult and high degree of suspicion should be present when approaching a patient with somatic pain and IM lesion on MRI, keeping in mind one differential of IM schwannoma.

Thin films of lead sulfide (PbS) are being extensively used for the fabrication of optoelectronic devices for commercial and military applications. In the present work, PbS films were fabricated onto a soda lime glass substrate by using an electron beam (e-beam) evaporation technique at a substrate temperature of 300 °C. Samples were annealed in an open atmosphere at a temperature range of 200–450 °C for 2 h. The deposited films were characterized for structural, optical, and electrical properties. Structural properties of PbS have been studied by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS), and Rutherford backscattering spectrometry (RBS). The results of XRD showed that the PbS thin film was crystalline in nature at room temperature with cubic crystal structure (galena) and preferential (111) and orientation (022). The morphology of the thin films was studied by FESEM, which also showed uniform and continuous deposition without any peel-off and patches. EDS analysis was performed to confirm the presence of lead and sulfur in as-deposited and annealed films. The thickness of the PbS film was found to be 172 nm, which is slightly greater than the intended thickness of 150 nm, determined by RBS. Ultraviolet-Visible-Near-Infrared (UV-Vis-NIR) spectroscopy revealed the maximum transmittance of ~25% for as-deposited films, with an increase of 74% in annealed films. The band gap of PbS was found in the range of 2.12–2.78 eV for as-deposited and annealed films. Hall measurement confirmed the carriers are p-type in nature. Carrier concentration, mobility of the carriers, conductivity, and sheet resistance are directly determined by Hall-effect measurement. The as-deposited sample showed a conductivity of 5.45 × 10−4 S/m, which gradually reduced to 1.21 × 10−5 S/m due to the composite nature of films (lead sulfide along with lead oxide). Furthermore, the present work also reflects the control of properties by controlling the amount of PbO present in the PbS films which are suitable for various applications (such as IR sensors).

Solidification consists of three stages at macroscale: subcooling, freezing and cooling. Classical two-phase Stefan problems describe freezing (or melting) phenomenon initially not at the fusion temperature. Since these problems only define subcooling and freezing stages, an extension to characterize the cooling stage is required to complete solidification. However, the moving boundary in solid-liquid interface is highly nonlinear, and thus exact solution is restricted to certain domains and boundary conditions. It is therefore vital to develop approximate analytical solutions based on physically tangible assumptions, like a small Stefan number. This paper proposes an asymptotic solution for a Stefan-like problem subject to a convective boundary for outward solidification in a hollow cylinder. By assuming a small Stefan number, three temporal regimes and four spatial layers are considered in the asymptotic analysis. The results are compared with numerical method. Further, effects of Biot numbers are also investigated regarding interface motion and temperature profile.