Secondary OA Research Articles

Correlation Between KL Gradings of OA Knee, Kinesiophobia and Pain Among School Teachers: A Cross-Sectional Study

Background: Osteoarthritis also known as degenerative arthritis or degenerative joint disease, is a group of mechanical abnormalities involving degradation of joints, including articular cartilage and subchondral bone. OA is the most common form of arthritis. There are two form of OA, Primary and Secondary OA. Kinesiophobia is a condition in which a patient has an excessive, irritational, and debilitating fear of physical movement and activity resulting from a feeling of vulnerability to painful injury or re injury. The influence of biological (exa-gray changes) as well as severity of pain, Kinesiophobia in individual physical functioning. There are less evidences showing the association of kinesiophobia and pain among school teachers with OA knee. So, this study was designed to find out the association of kinesiophobia and pain among school teachers with OA knee. Methodology: A cross-sectional observational study was conducted. 100 school teachers with unilateral or bilateral OA knee were selected who matched the selection criteria. Both male and female were included. For gradings of OA knee KL grade was taken, for kinesiophobia TAMPA scale was taken, for pain NPRS was taken as an outcome measures. Result: Spearman co-efficient between KL grade and TAMPA scale is 0.835, which indicates there is moderate to high positive correlation between KL grade and TAMPA scale. Spearman co-efficient between NPRS and TAMPA scale is 0.923, which indicates there is high positive (strong positive) correlation between NPRS and TAMPA scale. Spearman co-efficient between NPRS and KL grade is 0.784 which indicates there is moderate positive correlation between NPRS and KL grade. Conclusion: This study concludes that there is positive correlation between gradings of OA knee and kinesiophobia among teachers with OA knee. There is moderate positive correlation between gradings of OA and pain among teachers with OA knee. There is very high positive (Strong positive) correlation between kinesiophobia and pain among teachers with OA knee. Keywords: KL Gradings of OA Knee, OA knee, kinesiophobia, osteoarthritis

Comprehensive Study on Scoring and Grading Systems for Predicting the Severity of Knee Osteoarthritis.

Knee Osteoarthritis (KOA) is a degenerative joint ailment characterized by cartilage loss, which can be seen using imaging modalities and converted into imaging features. The older population is the most affected by knee OA, which affects 16% of people worldwide who are 15 years of age and older. Due to cartilage tissue degradation, primary knee OA develops in older people. In contrast, joint overuse or trauma in younger people can cause secondary knee OA. Early identification of knee OA, according to research, may be a successful management tactic for the condition. Scoring scales and grading systems are important tools for the management of knee osteoarthritis as they allow clinicians to measure the progression of the disease's severity and provide suggestions on suitable treatment at identified stages. The comprehensive study reviews various subjective and objective knee evaluation scoring systems that effectively score and grade the KOA based on where defects or changes in articular cartilage occur. Recent studies reveal that AI-based approaches, such as that of DenseNet, integrating the concept of deep learning for scoring and grading the KOA, outperform various state-of-the-art methods in order to predict the KOA at an early stage.

Seasonal characterization of chemical and optical properties of water-soluble organic aerosol in Beijing

Water-soluble organic aerosol (WSOA) plays a crucial role in altering radiative forcing and impacting human health. However, our understanding of the seasonal variations of WSOA in Chinese megacities after the three-year clean air action plan is limited. In this study, we analyzed PM2.5 filter samples collected over one year (2020−2021) in Beijing to characterize the seasonal changes in the chemical and optical properties of WSOA using an offline aerosol mass spectrometer along with spectroscopy techniques. The mean mass concentration of WSOA during the observation period was 8.84 ± 7.12 μg m−3, constituting approximately 64–67 % of OA. Our results indicate the contribution of secondary OA (SOA) increased by 13–28 % due to a substantial reduction in primary emissions after the clean air action plan. The composition of WSOA exhibited pronounced seasonal variations, with a predominant contribution from less oxidized SOA in summer (61 %) and primary OA originating from coal combustion and biomass burning during the heating season (34 %). The mass absorption efficiency of WSOA at 365 nm in winter was nearly twice that in summer, suggesting that WSOA from primary emissions possesses a stronger light-absorbing capability than SOA. On average, water-soluble brown carbon accounted for 33–48 % of total brown carbon absorption. Fluorescence analysis revealed humic-like substances as the most significant fluorescence component of WSOA, constituting 82 %. Furthermore, both absorption and fluorescence chromophores were associated with nitrogen-containing compounds, highlighting the role of nitrogen-containing species in influencing the optical properties of WSOA. The results are important for chemical transport models to accurately simulate the WSOA and its climate effects.

Increasing Contributions of Temperature-Dependent Oxygenated Organic Aerosol to Summertime Particulate Matter in New York City.

As part of the summer 2022 NYC-METS (New York City metropolitan Measurements of Emissions and TransformationS) campaign and the ASCENT (Atmospheric Science and Chemistry mEasurement NeTwork) observational network, speciated particulate matter was measured in real time in Manhattan and Queens, NY, with additional gas-phase measurements. Largely due to observed reductions in inorganic sulfate aerosol components over the 21st century, summertime aerosol composition in NYC has become predominantly organic (80-83%). Organic aerosol source apportionment via positive matrix factorization showed that this is dominated by secondary production as oxygenated organic aerosol (OOA) source factors comprised 73-76% of OA. Primary factors, including cooking-related organic aerosol (COA) and hydrocarbon-like organic aerosol (HOA) comprised minor fractions of OA, only 13-15% and 10-11%, respectively. The two sites presented considerable spatiotemporal variations in OA source factor concentrations despite similar average PM2.5 concentrations. The less- and more-oxidized OOA factors exhibited clear temperature dependences at both sites with increased concentrations and greater degrees of oxidation at higher temperatures, including during a heatwave. With strong temperature sensitivity and minimal changes in summertime concentrations since 2001, secondary OA poses a particular challenge for air quality policy in NYC that will very likely be exacerbated by continued climate change and extreme heat events.

Oncoprotective effects of chondroprotectors: glucosamine, chondroitin sulfate and undenatured type II collagen

Objective: to systematize fundamental, clinical, and epidemiological data on the oncoprotective effects of chondroprotectors: chondroitin sulfate (CS), glucosamine (including glucosamine sulfate, GS), and undenatured type II collagen (UC-II).Material and methods. A systematic computer analysis of 6176 publications on the relationship between CS/GS/UC-II and tumor diseases found by the query “(glucosamine OR chondroitin OR ((“Collagen Type II” OR “type II collagen”) AND pharmacology)) AND (Cancer OR cancers OR tumor OR tumors OR tumors OR tumour*) NOT tumor necrosis)” in PubMed and Embase databases was performed. All articles of any format from 1900 to the present day with full available abstracts were taken. A topological approach to data analysis was used.Results. Large-scale clinical and epidemiological studies and meta-analyses showed that regular consumption of CS/GS reduced the risk of colorectal cancer and lung cancer, as well as mortality from tumor diseases. The mechanisms of oncoprotective action of CS/GS are through inhibition of the pro-inflammatory cascade of tumor necrosis factor alpha, CD44 receptor and nuclear factor kappa B, and initiation of tumor cell apoptosis. By modulating the CD44 receptor and specific O-glycosylation of intracellular proteins, GS inhibits the pro-inflammatory effects of arachidonic acid cascade, interleukins IL-6, IL-8, the PI3K/Akt proliferative pathway, and cyclin-dependent kinases. The first postgenomic studies of CS/GS oncoprotective effects, including microbiome studies, was performed. Additionally, CS contributes to the inhibition of the effects of vascular endothelial growth factor and matrix metalloproteinases involved in tumor metastasis and invasion. Potentially, CS/GS oncoprotective effects may be enhanced by the anti-inflammatory effect of UC-II: the addition of NC-II substance to CS/GS complex makes it possible to reduce the autoimmune branch of pathogenesis not only in primary, but also in secondary OA and rheumatoid arthritis.Conclusion. The CS and glucosamine (including GS) chondroprotectors exhibit oncoprotective effects. The use of CS and GS together with UС-II standardized pharmaceutical forms can enhance their anti-inflammatory and immunomodulatory effects.

Factors that affect external rotation following reverse shoulder arthroplasty: a retrospective multi-centre study on 501 shoulders.

The purpose of this multi-centre study was to assess external rotation in a large cohort following reverse shoulder arthroplasty (RSA) at a minimum follow-up of 2years, and identify factors that influence postoperative and/or net-improvement of external rotation. The authors retrospectively reviewed records of 743 RSAs performed between January 2015 and August 2017 by 16 surgeons that participated in a large national society symposium; 193 (25.7%) were lost to follow-up, 16 (2.1%) died, and 33 (4.4%) were revised with implant exchange, which left 501 available for assessment at 2.0-5.5years. Pre- and post-operative active forward elevation, active external rotation (ER1), active internal rotation (IR1) and constant score (CS) were collected. Regression analyses were performed to determine associations of patient demographics, surgical and implant parameters, rotator cuff muscles status and radiographic angles with ER1. Multivariable analyses revealed postoperative ER1 decreased with age (β, - 0.35), increased with lateralisation shoulder angle (LSA) (β, 0.26), and was better in shoulders operated by the antero-superior (AS) approach (β, 11.41), but worse in shoulders with absent/atrophic teres minor muscles (β, - 10.06). Net-improvement of ER1 increased with LSA (β, 0.39), was better with inlay stems (β, 8.33) and BIO RSA (β, 6.22), but worse in shoulders operated for primary OA with rotator cuff (RC) tears (β, - 16.26), for secondary OA due to RC tears (β, - 16.06), or for mRCT (β, - 18.96). This large multi-centre study revealed that, at a minimum of 2years following RSA, ER1 improved by 16.1°. Postoperative ER1 was better in shoulders which had normal or hypertrophic teres minor muscles, were operated by the AS approach, or with greater LSA. Net-improvement of ER1 was better in shoulders with inlay stems, with BIO RSA, or with greater LSA, but worse in shoulders with rotator cuff deficiency. IV.

Minimally invasive surgery supercapsular percutaneously-assisted total hip (SuperPath) arthroplasty.

The benefits of minimally invasive surgical techniques in total hip arthroplasty (THA) are well known, but concerns about applying SuperPATH in patients with secondary OA of acetabular dysplasia do not have been reported. We aim to evaluate whether SuperPATH is applicable to secondary OA, furthermore, to quantify the recovery of lower extremity function. 30 patients with secondary OA admitted for THA applying SuperPATH were investigated. Clinical Japanese Orthopaedic Association (JOA) Score and radiographical evaluation were performed. Following was examined pre- and early post-operatively; pain level, blood tests, TUG and 10-M walking time for lower limb recovery. Preoperative radiographic measurements revealed an average Sharp angle of 46.2 ± 2.8 degrees and CE angle of 19.4 ± 7.3 degrees. 29 THAs had Crowe Type I and 1 THA had Crowe Type II. JOA score improved from 48.8 preoperatively to 91.5 at 2 months postoperatively. The perioperative pain assessment (VAS) averaged 7.0±1.5 preoperatively, 4.6±2.6 on the first postoperative day, then decreased gradually to 1.2±1.4 at 2 weeks. Blood data showed that creatine kinase, myoglobin, and CRP were significantly elevated on the day after surgery, but they normalized at 2 weeks postoperatively. Both TUG and 10M walking time showed slightly higher values at 1 week postoperatively compared to preoperatively but recovered to the same level as preoperatively at 2 weeks after surgery. Our data suggests that SuperPATH approach to THA for dysplastic OA was applicable to mildly dysplastic OA and achieved an early recovery of lower limb function.

Fine aerosol sources at an urban background site in the Eastern Mediterranean (Nicosia; Cyprus): Insights from offline versus online source apportionment comparison for carbonaceous aerosols

A total of 348 daily PM2.5 samples were collected at an urban background site of Nicosia, capital of Cyprus, for one-year period (October 2018–October 2019) to assess the origin and sources of fine PM at the Eastern Mediterranean, a poorly characterized area of the world.The samples were analysed for water soluble ionic species, elemental and organic carbon, carbohydrates and trace metals, the combination of which were utilized to identify pollution sources by applying Positive Matrix Factorization (PMF). Six PM2.5 sources, namely long-range transport (LRT; 38 %), traffic (20 %), biomass burning (16 %), dust (10 %), sea salt (9 %) and heavy oil combustion (7 %), were identified.Despite sampling in an urban agglomeration, the chemical fingerprint of the aerosol is largely dictated by air mass origin rather than local sources. Springtime is characterized by the most elevated particulate levels due to the southerly air masses carrying particles from the Sahara Desert. Northerlies are observed throughout the year but are predominant during summer allowing the LRT source to peak (54 % during summer). Only during winter, due to extensive use of biomass combustion for domestic heating (36.6 % during winter), local sources dominate.A co-located online PMF source apportionment of submicron carbonaceous aerosols (Organic Aerosols, OA; Black Carbon) was performed by the means of an Aerosol Chemical Speciation Monitor (for OA) and an Aethalometer (for BC) for a four-month period. The comparison between the two methodologies allowed to better assess the robustness and limitations of the two methodologies. More specifically, LRT OA and biomass burning BC apportioned by the offline PMF showed a strong consistency with the online apportioned more oxidized oxygenated OA and BCwb, respectively; cross validating these sources. On the other hand, our traffic factor may contain additional hydrocarbon-like OA and BC from fossil fuel sources other than just vehicular emissions. Finally, the offline biomass burning OA source is likely to contain both primary and secondary OA.

Online chemical characterization of atmospheric fine secondary aerosols and organic nitrates in summer Nanjing, China

The mechanisms leading to secondary aerosol pollution in the Yangtze Delta region (such as Nanjing) are still poorly constrained. Here we conducted a field campaign to elucidate the chemical characteristics of fine aerosols, with a focus on variations and formation mechanisms of secondary components in summer Nanjing. The average PM1 mass concentration was 18.88 μg m−3 and was dominated by the secondary species (78%). Secondary inorganic species accounted for 30% of PM1 mass and high PM1 loading was closely relevant with nitrate rather than sulfate. Nitrate was mainly produced from nighttime heterogeneous/aqueous process (production rate of 0.38 g/g H2O) and its variation was driven by thermodynamic equilibrium. On the other hand, sulfate was governed by daytime photochemical production (production rate of 0.013 g/g Ox)(Ox=NO2 + O3) while contribution of aqueous process was minor. Positive matrix factorization identified and quantified a traffic-related hydrocarbon OA (HOA), a cooking OA (COA), and four SOA factors including a local secondary OA (LSOA), a less oxygenated OA (LO-OOA), a moderately oxygenated OA (MD-OOA), and a more-oxidized oxygenated OA (MO-OOA). LSOA was likely from local photochemical conversion of HOA and COA; LO-OOA was semi-volatile thus evaporation/diffusion would offset its weak photochemical production. MO-OOA was very clearly linked with photochemistry, based on its afternoon enhancement and tight positive correlations with Ox (0.029 g/g Ox, occupying ∼60% of photochemical SOA production) and sulfate. MD-OOA was a minor contributor of SOA (∼6%) but it was clearly from aqueous process given the strong positive correlation with aerosol liquid water content (ALWC) and nitrate. Both nitrate and MD-OOA concentrations increased against pH while those of sulfate and MO-OOA decreased. We further investigated the organic nitrate (ON) characteristics, and found that ON was a very minor component of OA in summer Nanjing (0.08–0.14 μg m−3, 0.6–1.1% of OA) and it was predominantly associated with aqueous process. Overall, this work reveals in details formation processes of different secondary species, and therefore is insightful for future air pollution modelling and efficient control in similar regions.

Void space and secondary oriented attachment mechanisms in cerium oxide nanorods

Two new processes occurring during nanorod annealing of ceria are disclosed, both belonging to the wider “oriented attachment” (OA) scheme of crystal growth, which commonly drives nanoparticles growing into nanorods. The first new process is an inversion of the standard OA, where the usual solid particles are replaced by well-facetted shape-equilibrated voids inside larger single crystals. The internal facetted voids are then found to aggregate during dry heat treatment into rod-shaped elongated voids growing eventually towards nanotubes. For the case of CeO2, a perfect equivalence is found between positive OA, involving cuboctahedral {111}/{100} nanoparticles turning into {110}/{100} nanorods, and negative or void space OA, where cuboctahedral voids turn into negative tubular rods of same indexing. The second OA process (“secondary OA”) concerns aggregation of small nanorod segments into larger, double, or quadruple sized nanorods, with perfection of alignment and bonding exceeding simple van der Waals forces. Eventually, the new rods merge into single crystal grain boundary–free larger rods, but with an external shape, including double-ended rods, indicating their origin from several rods. Both processes are found on identical samples and occur in parallel.

Sources and processes of water-soluble and water-insoluble organic aerosol in cold season in Beijing, China

Abstract. Water-soluble and water-insoluble organic aerosol (WSOA and WIOA) constitute a large fraction of fine particles in winter in northern China, yet our understanding of their sources and processes are still limited. Here we have a comprehensive characterization of WSOA in cold season in Beijing. Particularly, we present the first mass spectral characterization of WIOA by integrating online and offline organic aerosol measurements from high-resolution aerosol mass spectrometer. Our results showed that WSOA on average accounted for 59 % of the total OA and comprised dominantly secondary OA (SOA, 69 %). The WSOA composition showed significant changes during the transition season from autumn to winter. While the photochemical-related SOA dominated WSOA (51 %) in early November, the oxidized SOA from biomass burning increased substantially from 8 % to 29 % during the heating season. Comparatively, local primary OA dominantly from cooking aerosol contributed the major fraction of WSOA during clean periods. WIOA showed largely different spectral patterns from WSOA which were characterized by prominent hydrocarbon ions series and low oxygen-to-carbon (O/C = 0.19) and organic mass-to-organic carbon (OM/OC = 1.39) ratios. The nighttime WIOA showed less oxidized properties (O/C = 0.16 vs. 0.24) with more pronounced polycyclic aromatic hydrocarbons (PAHs) signals than daytime, indicating the impacts of enhanced coal combustion emissions on WIOA. The evolution process of WSOA and WIOA was further demonstrated by the triangle plot of f44 (fraction of m/z 44 in OA) vs. f43, f44 vs. f60, and the Van Krevelen diagram (H/C vs. O/C). We also found more oxidized WSOA and an increased contribution of SOA in WSOA compared with previous winter studies in Beijing, indicating that the changes in OA composition due to clean air act have affected the sources and properties of WSOA.

Evaluation of Functional Outcome and Complications after Open Reduction and Internal Fixation of Acetabulum Fractures

Background: The present study was done to evaluate the functional outcome and complications after open reduction and internal fixation of acetabulum fractures. Material and methods: The present study was done in 44 patients of fracture acetabulum managed by open reduction internal fixation in the Department of Orthopaedic surgery, Indira Gandhi Medical College, Shimla. Results: There were 16 prospective (36.4%) and 28 retrospective (63.6%) cases. The mean age was 45.07 years with maximum number of 39 (88%) patients in the age group of 21- 60 years. Majority (77.3%) of the patients was males and 22.8 % were females. Modified Merle d’Aubigne and postel (MDA) score was excellent in 77%patients, good in 13%, fair in 10%. Matta’s radiological score at final follow up was excellent in 54.55%, good in 36.36%, fair in 4.55% and poor in 4.54% patients. The average Modified Harris Hip score was 94 at final follow up in 44 patients. Patients with anterior column fracture had HHS of 96 at final follow up; posterior wall fracture patients had average HHS of 92 at final follow up. Two patients had complications. One patient had femoral head fracture along with fracture of posterior wall developed AVN and also had subsequently Secondary OA with post-operative subluxation of femoral head. Thus three complications were seen in this patient. Another patient with fracture dislocation with fracture of posterior wall developed AVN and subsequently secondary OA 5 year after surgery. No patient developed sciatic nerve injury post operatively. None of patients developed postoperative sciatic nerve palsy. No patient died during treatment or follow up. Conclusion: Open reduction and internal fixation as a gold standard for acetabulum fractures which is indicated with excellent to good results in majority of the patients as assessed by Modified Merle d’Aubigne score, Modified Harris hip score and Matta Radiological score with minimal complications at final follow up.

Effect of Structured Spinal Exercise as an Adjunct to Knee Specific Exercise in Bilateral Knee Osteoarthritis Patients

Background: Osteoarthritis is a condition which causes the joint inflammation that results from cartilage degeneration. There are two types of osteoarthritis one primary OA and second secondary OA. The conventional treatment TENS, Ultrasound, IFT, along with knee specific exercises in one group. And the second group focused on the spinal exercises with all these conventional approaches. The purpose of the study was to see the effect of spinal exercises effect on knee OA symptoms and functional ability. The significant difference was found in the pain , range of motion and the timed -up-go test. Methods: Total 30 participants were selected. groups of two were done one experimental given the spinal exercise and conventional treatment second controlled group given the knee exercises and conventional management. The pain, ROM and TUGT were analysed pre and post treatment. Results: According to statistical analysis, the study showed a significant difference in the pain intensity, ROM of knee and TUGT pre and post intervention. The study documented difference in the pain intensity post-intervention (0.0004) at rest and (0.0002) on activity and range of motion of right knee (<0.0001) and of left knee (<0.0001), timed up go test (0.0110) considered significant. Conclusion: The conducted study shows that there was significant difference in values of pain, ROM of knee and timed up go test in experimental group compared to controlled group. So, the spinal exercises have proven beneficial in knee osteoarthritis. KEYWORDS: Osteoarthritis, visual analogue scale, kellgren and Lawrence classification, spinal exercises.

Rapid transition of aerosol optical properties and water-soluble organic aerosols in cold season in Fenwei Plain

The Fenwei Plain (FWP) continues to be one of the most polluted regions in China despite the improvement of air quality in recent years. However, our understanding of aerosol optical properties (AOP) and its relationship with aerosol composition particularly in cold season is far from complete. Here we conducted three-month measurements of AOP from November 2020 to January 2021 in the FWP along with fine particle composition and water-soluble organic aerosol (WSOA) measurements. Our results showed rapid transitions in AOP from November to January due to the enhanced primary emissions and the decreased aqueous-phase processing. The single scattering albedo (SSA) decreased from 0.85 to 0.78, while the absorption Ångstrӧm exponent (AAE) increased from 1.41 to 1.60, demonstrating the increasing role of absorbing aerosol and brown carbon in cold season. Further analysis showed that SSA increased significantly with the fraction of secondary inorganic aerosol, while AAE was highly correlated with the fraction of primary OA (POA), highlighting the different impacts of primary and secondary aerosol on AOP. Chemical apportionment showed the dominant contributions of ammonium nitrate (29%) and ammonium sulfate (27%) to particle extinction before heating season, while that of POA increased to 27% during heating season. Although the pollution level showed a clear increase during the heating season, the changes in visibility were small due to the decreased mass extinction efficiency from 3.48 to 2.91 m2 g−1. Positive matrix factorization illustrated a clear transition in WSOA composition from the dominance of secondary OA (SOA) in November to POA in heating season. Compared with the large decrease in water-soluble aqueous-phase SOA, the consistently high concentration of photochemical-related SOA elucidated the presence of strong photochemical processing in cold season. Overall, our results demonstrate the significant transition in primary emissions and secondary formation in cold season, and such changes have affected AOP substantially.

Unexpected Increases of Severe Haze Pollution During the Post COVID‐19 Period: Effects of Emissions, Meteorology, and Secondary Production

AbstractUnexpectedly frequent severe haze episodes were observed in Beijing during February–March in 2021 after two phases of clean air action plan (2013–2020), yet the causes remained unclear. Here, we conducted real‐time fine particle (PM2.5) composition measurements during January–March in 2021 using a time‐of‐flight aerosol chemical speciation monitor and an aethalometer and compared with those during the coronavirus disease (COVID‐19) period in 2020. Our results showed ubiquitously elevated concentrations of chloride, black carbon (BC), and primary organic aerosol (POA) in 2021, suggesting increased primary emissions during the post‐COVID‐19 period. By using the machine learning‐based random forest (RF) algorithm, we found largely different responses of aerosol changes to meteorology in different months. After decoupling the effects of meteorology, the PM2.5 changes from 2020 to 2021 were reduced from −35.6% to −29.0% in January, −24.1% to −4.5% in February, and +92.6% to +34.2% in March, respectively. Our results demonstrate the dominant roles of stagnant meteorology and secondary production in the formation of severe haze episodes in March 2021. In particular, we found that the compositions of observed and deweathered PM2.5 were fairly similar between 2020 and 2021, and the ratios of secondary OA to secondary inorganic aerosols were close. Our study indicates that decoupling the influence of meteorological conditions is of great importance for better evaluation of mitigating strategies of air pollution due to the large impact of meteorology on the changes in PM2.5 species particularly in a short period.

Investigation of sources and formation mechanisms of fine particles and organic aerosols in cold season in Fenhe Plain, China

Air quality has been improved significantly from 2017 to 2020 in Fenhe Plain, one of the most polluted regions in China. However, severe haze episodes from days to weeks were still frequently observed in cold seasons, and the sources and formation mechanisms especially organic aerosols are poorly understood due to the limited highly time-resolved measurements. Here we have a comprehensive characterization of chemical composition, variations and sources of fine particles in fall and winter in Fenhe Plain mainly using a PM2.5 Aerosol Chemical Speciation Monitor. Our results showed that organics and nitrate were two major species of PM2.5, on average accounting for 35.4% and 27.0%, respectively, and they played consistently important roles across different pollution levels. Positive matrix factorization revealed three primary sources from traffic, biomass burning and coal combustion emissions, and two secondary factors that are associated with photochemical and aqueous-phase processing. While secondary OA (SOA) dominated OA for the entire study (63%), large increases in primary OA from 19% to 41% were observed during heating period. Particularly, we found a high contribution of photochemical OOA (45%) during severely polluted periods in heating season demonstrating the presence of strong photochemical production in winter. Most aerosol species presented similarly pronounced diurnal cycles with low concentrations during daytime indicating the major influences from planetary boundary layer and primary emissions. The bivariate polar plots further illustrated the different sources of primary and secondary species, i.e., local emissions versus regional transport from the south and southeast. By analyzing four case studies, we found three major formation mechanisms of severe haze episodes that were driven by photochemical processing, aqueous-phase production, and local emissions, respectively. Therefore, different mitigating strategies are suggested in Fenhe Plain depending on the types of severe haze episodes.

Comparative analysis of the results and complications of two methods of the open wedge high tibial osteotomy

Objective – to compare the results and complications of open wedge high tibial osteotomy (OWHTO) in patients operated on according to the standard technique and using the developed method of performing the operation using the original fixator.Materials and methods. 73 patients with primary and secondary OA of the knee I–III stages were recruited into the study, which were divided into 2 groups. Group 1 consisted of 43 patients, who underwent 46 OWHTO from 2005 to 2019 using the standard technique using short plates with a fixed spacer (Puddu I (5 times) and II generation (24 times), Osteomed (17 times)) and bone grafting. Group 2 consisted of 30 patients who were operated on in 2018– 2020 using the developed surgical technique and the original fixator. To assess the result, we studied the change in pain according to the Visual Analog Scale (VAS), as well as the functional (FS) and objective scores (OS) of the knee according to the Knee Society Score (KSS) before surgery, after 3 months and 1 year after OWHTO.Results. In group 1, one year after OWHTO, the results were obtained: excellent in 43.5% of cases, good – in 41.0% and satisfactory – in 15.2% of patients. In group 2, an excellent result was obtained in 59.3% of patients, good – in 33.4% and satisfactory – in 7.3% of cases. In group 1, 15 (32.7%) patients were diagnosed with 26 complications, and in group 2 – 5 (16.6%) patients with 5 complications.Conclusions. The use of the developed surgical technique and the original fixator made it possible to increase the percentage of excellent and good treatment results from 84.5% to 92.7% and to reduce the number of complications associated with OWHTO from 32.7% to 16.6%.

Autologous Bone Marrow Mononuclear Cells (BMMCs) for the Treatment of Uncomplicated Grade 2 Ununited Anconeal Process (UAP) in Six Dogs: Preliminary Results.

The aim of this study was to report the results of autologous bone marrow mononuclear cell (BMMC) transplantation as a minimally invasive treatment for grade 2 UAP in dogs. This was an observational case series on six German shepherd dogs affected by grade 2 UAP as defined according to their clinical condition as well as radiographic and CT findings. Bone marrow was collected from the iliac crest and the mononuclear fraction was separated with density gradient centrifugation. Cells were suspended in fibrin glue before BMMC administration and implanted via transcutaneous injection under IB or CT guidance, using a spinal needle directly inserted into the ossification centre between the anconeal process and the olecranon. Clinical and radiographic follow-up was performed for up to 6 months. Microradiographic assessment was performed on one dog that died of other causes. A progressive reduction of pain within 3 weeks after BMMC administration was observed in all dogs, with gradually increased weight bearing on the affected limb. Radiographic and CT follow-up revealed the progressive fusion of the ossification centre at 90 days without any signs of secondary OA. The examination of microradiographs showed newly formed bone tissue in which a residue of calcified cartilage was present at the site of BMMC implantation. On the basis of these results, BMMC therapy for grade 2 UAP may be considered to be an effective and minimally invasive treatment option for dogs.

Real‐Time Characterization of Aerosol Compositions, Sources, and Aging Processes in Guangzhou During PRIDE‐GBA 2018 Campaign

AbstractTo investigate the chemical compositions, sources, and aging processes of submicron particles (PM1), a comprehensive field campaign was conducted in Guangzhou urban area of China during the autumn (October–November) of 2018. The average mass concentration of PM1 was 35.6 ± 20.8 µg m−3, which was mainly contributed by organic aerosols (OA, 42%), then followed by sulfate (25%) and inorganic nitrate (11%). The inorganic nitrate was found to be the main driving component (up to ∼50%) to account for the fast increase of PM1 during the polluted periods of Guangzhou autumn. The promotion effects of sulfate, aerosol liquid water content, and particles acidity on nitrate formation were systematically discussed. Source apportionment results showed 72% of OA in Guangzhou autumn was contributed by secondary OA (SOA), and 28% of primary OA (POA), including vehicle emission related hydrocarbon‐like OA (HOA, 16%), nitrogen‐containing OA (NOA, 3%) and cooking OA (COA, 8%). To explore the aging processes of OA, the dynamic variations of OA and its oxidation level as a function of ambient photochemical age are shown. Using an in situ field‐deployed oxidation flow reactor, the heterogeneous reaction rate coefficients of ambient POA with OH radicals () were estimated to be 4.0–5.4 × 10−13 cm3 molecules−1 s−1, which is equivalent to a lifetime of POA >2 weeks. The long heterogeneous lifetime of POA supports gas phase oxidation was the major pathway for ambient OA aging. The OH uptake coefficient () was estimated to be 0.76–0.84, underlining that OH radicals can be taken up efficiently on ambient aerosols.

A STUDY OF PRIMARY TOTAL KNEE ARTHROPLASTY (TOTAL KNEE REPLACEMENT) IN SEVERE DEGENERATIVE OSTEO ARTHRITIS OF KNEE

AIM: To assess the clinical outcome, to study radiological variable inuencing the outcome of total knee arthroplasty and to identity patient variable which signicantly inuence the outcome. Out MATERIALS&METHODS: of the 30 Arthroplasties performed in 28 patients with in the study period. 5 patients (5 knees) were lost to follow-up for various reasons and thus 23 patients (25 knees) were available for clinical review. The mean age of the patient RESULTS: at the time of surgery was 61.04 years. 76% of Knee had primary osteoarthritis and 25% had secondary OA. The average post-operative alignment as 4.3º valgus (range, 3º varus-10º valgus), the mean posterior slope of tibia (s) was 3.5º (range, 0-8º)c and the average femoral exion angle (?) 7.6º. In the assessment of post CONCLUSION: operative outcome of total knee arthroplasty, Knee Society Score is a very useful tool. Restoration of normal alignment of valgus (6 + 2º) is possible with conventional (without computer assisted navigation) surgical technique.