Low Load Research Articles

Impact of Psychosocial Resources on Mental Health During the Transition From the Initial Rehabilitation to Community: The Case of Spinal Cord Injury.

This study aims to examine the change in mental health from the clinical to community setting in persons with spinal cord injury and to identify the role of psychosocial resources for this transition. Longitudinal survey self-report data from N = 240 persons with spinal cord injury from the Swiss Spinal Cord Injury Cohort study. Latent profile analysis identified three profiles for each the clinical and the community setting: low, medium, and high mental health load. Latent transition analysis revealed that persons with spinal cord injury were most likely to stay in the same profile from discharge of initial rehabilitation to community, followed by a decrease from a high mental health load to a medium mental health load and an increase from a low mental health load to a medium mental health load. Individuals staying in the low mental health load profile showed significantly higher levels of psychosocial resources compared to individuals increasing to the medium mental health load profile, whereas individuals who stayed in the high mental health load profile showed lower levels of psychosocial resources compared to individuals decreasing to the medium mental health load profile. This study highlights a positive role of psychosocial resources on mental health transitions, underlining the need for strengthening psychosocial resources beyond initial rehabilitation.

Very low Ru loadings boosting performance of Ni-based dual-function materials during the integrated CO2 capture and methanation process

Herein, the effect of the Ru:Ni bimetallic composition in dual-function materials (DFMs) for the integrated CO2 capture and methanation process (ICCU-Methanation) is systematically evaluated and combined with a thorough material characterization, as well as a mechanistic (in-situ diffuse reflectance infrared fourier-transform spectroscopy (in-situ DRIFTS)) and computational (computational fluid dynamics (CFD) modelling) investigation, in order to improve the performance of Ni-based DFMs. The bimetallic DFMs are comprised of a main Ni active metallic phase (20 wt%) and are modified with low Ru loadings in the 0.1–1 wt% range (to keep the material cost low), supported on Na2O/Al2O3. It is shown that the addition of even a very low Ru loading (0.1–0.2 wt%) can drastically improve the material reducibility, exposing a significantly higher amount of surface-active metallic sites, with Ru being highly dispersed over the support and the Ni phase, while also forming some small Ru particles. This manifests in a significant enhancement in the CH4 yield and the CH4 production kinetics during ICCU–Methanation (which mainly proceeds via formate intermediates), with 0.2 wt% Ru addition leading to the best results. This bimetallic DFM also shows high stability and a relatively good performance under an oxidizing CO2 capture atmosphere. The formation rate of CH4 during hydrogenation is then further validated via CFD modelling and the developed model is subsequently applied in the prediction of the effect of other parameters, including the H2 inlet concentration, inlet flow rate, dual-function material weight, and reactor internal diameter.

Tensile fracture behavior and friction and wear properties of TiB2 particle reinforced Al-Si matrix composites

In this study, TiB2/Al-Si composite material was fabricated by addition of Al-TiB2 master alloy, and the influence of varying micro-sized TiB2 particle content on the mechanical and tribological properties of the composite material was investigated. The results revealed that the introduction of TiB2 particles effectively refined the Al-Si matrix alloy microstructure, thereby enhancing the mechanical properties and wear resistance of the Al-Si matrix alloy. When the TiB2 particle content reached 0.8 wt%, the composite material exhibited optimal mechanical properties with a tensile strength of 318 MPa and elongation of 7.2 %, improving of 8.9 % and 69.1 %, respectively, compared to the matrix alloy. Moreover, wear rates of the composite material demonstrated significantly lower than the matrix alloy under different loading conditions in this paper. The improved mechanical properties of the composite material were attributed to grain refinement strengthening, second phase strengthening and the coefficient of thermal expansion strengthening. Under low loads, abrasive wear was the dominant wear mechanism; while under high loads, a combination of abrasive and adhesive wear occurred. The addition of TiB2 particles effectively enhanced the hardness of the matrix alloy, reduced the dynamic friction coefficient, suppressed adhesive wear, and improved the wear resistance of the composite material.

Exergy analysis of a diesel methanol dual fuel engine with different regulatory strategies for meeting China VI emission regulations

To reveal the mechanism for high brake thermal efficiency (BTE) of diesel methanol dual fuel (DMDF) engine meeting China VI emission regulations without urea, experimental and computational methods were used to study the exergy distribution with different regulatory strategies. As the methanol energy ratio (MER) increased, the incomplete combustion exergy loss increased from 0.3 % to 5.5 %, while the exhaust exergy loss and heat transfer exergy loss decreased slightly. As the HP-EGR increased from 3 % to 23 %, exergy losses of incomplete combustion and exhaust decreased, resulting in a reduction in the engine exergy losses. As the LP-EGR increased from 3 % to 21 %, the exergy losses of heat transfer and incomplete combustion slightly decreased. By advancing the main injection timing, the decrease in exhaust flow rate and temperature led to a decrease in exhaust exergy loss and the combustion efficiency was improved from 95.0 % to 96.5 %. Both of them resulted in the highest exergy efficiency of 35.2 % at 12°CA BTDC. Finally, the exergy distributions of DMDF and diesel modes were compared at high and low loads. The research results can provide theoretical basis and engineering practical value for the development and optimization of DMDF engines from the perspective of exergy.

A Systematic Approach for Estimating Colloidal Particle Adsorption Model Parameters

The estimation of ion- exchange chromatography model parameters is crucial to enable efficient model-assisted biopharmaceutical downstream process development. Model calibration methods can be hindered by model limitations combined with parameter correlations, leading to time-consuming repeated parameter estimations. While Steric Mass Action isotherm estimation methods exist, there is a need for a systematic approach to estimate model parameters for an emerging Colloidal Particle Adsorption (CPA) model proposed by Briskot et al. This study presents a novel strategy that addresses this challenge, offering significant improvements.Through a parameter sensitivity analysis, we identified key levers for improved CPA parameter estimation, enabling the prediction of elution behavior for low and high load densities in gradient and step elution mode. This analysis also revealed the correlation structure of parameters, allowing the establishment of a minimalized experimental data set for parameter estimation, by using one breakthrough, a high load and three low load density gradient elution experiments. Our workflow leverages a surrogate-assisted global-optimization tool, minimizing computationally expensive function evaluations during parameter fitting. Furthermore, we employed a customized objective function, specifically adapted to the model structure and sensitivity results, to enhance the solver's performance.Our strategy was tested on three model proteins with molecular weights of approximately 50, 150 and 200 kDa using a strong cation exchange Poros 50 HS resin. Our final approach enabled high throughput CPA model calibration for single components. The resulting CPA models were able to describe non-binding protein-pulses, low and high-loaded gradient elution, break through, as well as isocratic elution experiments.

Green Synthesis, Characterization, and Catalytic Applications of CuO Nanoparticles Using Prosopis Cineraria Seed Extract

Abstract The current study used a seed extract of Prosopis cineraria as a stabilizing and reducing agent to produce CuO nanoparticles via an easy, low-cost, affordable, and environmentally friendly synthesis process. The formation of copper oxide nanoparticles and the maximum absorbance of the CuO nanoparticles produced in the solution at 565 nm were verified by UV-vis. Copper oxide nanoparticles were found to have secondary metabolites on their surface, as shown by a distinctive Cu-O stretching band at 532 cm−1, which confirmed the reduced Cu2+ ions in copper oxide nanoparticles. This was confirmed by FTIR analysis. The XRD analysis confirmed the produced copper oxide nanoparticles’ monoclinic crystalline nanostructure with an average particle size of 34 nm. The phytonutrients in Prosopis cineraria seed extract stabilized and reduced copper, as demonstrated by the existence of copper and oxygen atoms at 85.2% and 12.5%, respectively, as demonstrated by SEM-EDX analysis. According to the HR-TEM study, copper oxide nanoparticles with a mean size of 18 nm are spherical in shape and well distributed. Prosopis cineraria seed extract-derived copper oxide nanoparticles were utilized as a catalyst in the Ullmann process to produce diphenyl ether. CuO nanoparticles produced by Prosopis cineraria seed extraction as a catalyst yielded 91% diphenyl ether. The results showed that a more ecologically friendly way of synthesizing copper oxide nanoparticles with great homogeneity of particle sizes could be achieved using seed extract. This work aims to facilitate heterogeneous catalysis from CuO nanoparticles utilising Prosopis cineraria seed extract. Overall, this technique offers several advantages, like high yields at fast reaction times, and low catalyst loading are just a few of this approach’s many benefits.

3D printed TC4 titanium alloy bone scaffolds with TNTs-VA-PLGA composite coating on the surface:improved infection resistance and biocompatibility

Titanium-based bone scaffolds are prone to aseptic infection and loosening after implantation,which seriously limits their clinical applications. Preparation of titanium dioxide nanotubes (TNTs) on the surface of the scaffolds and loading of anti-infective drugs is an effective method to solve this problem, but the current TNTs prepared on the surface of titanium-based scaffolds have a high internal and external variability in morphology and low drug loading capacity. In this study, we prepared TNTs on the surface of three kinds of TC4 titanium alloy scaffolds with TPMS structure with controllable morphology, tube diameter of 90-125 nm and tube length of 14-35 μm,and the difference between inner and outer diameters of the tubes was less than 2 μm,and the drug released from the composite scaffolds was maintained at a concentration of more than 1.5 μg/ml within 11 days after loading anti-infective drug Vancomycin-polylactic acid-hydroxyacetic acid copolymer(VA-PLGA) on the surface of the TNTs. Based on the simulation of drug release, the TNTs-VA-PLGA drug delivery system conforms to the Korsmeyer-Peppas model. Cell experiments confirmed that the composite scaffolds significantly increased cell proliferation by 65.33% compared with the unmodified scaffolds. The results indicated that the TNTs coating containing vancomycin and polylactic acid-hydroxyacetic acid copolymer had a promising application in orthopedic implants.

Parameters of Performance: A Deep Dive into Liquid-to-Air CDU Assessment

The rapid growth in data center workloads and the increasing complexity of modern applications have led to significant contradictions between computational performance and thermal management. Traditional air-cooling systems, while widely adopted, are reaching their limits in handling the rising thermal footprints and higher rack power densities of next-generation servers, often resulting in thermal throttling and decreased efficiency, emphasizing the need for more efficient cooling solutions. Direct-to-chip liquid cooling with cold plates has emerged as a promising solution, providing efficient heat dissipation for high-performance servers. However, challenges remain, such as ensuring system stability under varying thermal loads and optimizing integration with existing infrastructure. This comprehensive study digs into the area of data center liquid cooling, providing a novel, comprehensive experimental investigation of the critical steps and tests necessary for commissioning coolant distribution units (CDUs) in direct-to-chip liquid-cooled data centers. It carefully investigates the hydraulic, thermal, and energy aspects, establishing the groundwork for Liquid-to-Air (L2A) CDU data centers. A CDU’s performance was evaluated under different conditions. First, the CDU’s maximum cooling capacity was evaluated and found to be as high as 89.9 kW at an approach temperature difference (ATD) of 18.3 °C with a 0.83 heat exchanger effectiveness. Then, to assess the cooling performance and stability of the CDU, a low-power test and a transient thermohydraulic test were conducted. The results showed instability in the supply fluid temperature (SFT) caused by the oscillation in fan speed at low thermal loads. Despite this, heat removal rates remained constant across varying supply air temperatures (SATs), and a partial power usage effectiveness (PPUE) of 1.042 was achieved at 100% heat load (86 kW) under different SATs. This research sets a foundation for improving L2A CDU performance and offers practical insights for overcoming current cooling limitations in data centers.

Construction of cobalt zinc metal-organic frameworks derived Co/CoO/C composites toward broadband and high-efficiency electromagnetic wave absorption

The fabrication of novel carbon-based electromagnetic wave (EMW) absorbers with broad absorption bandwidth, strong absorption strength, low filler loading ratio and thin matching thickness remains a challenging task. Metal-organic frameworks (MOFs) are widely recognized as ideal self-sacrificial templates for the construction of carbon-based EMW absorbers. In this work, bimetallic CoZn-MOFs derived Co/CoO/C composites were prepared by combining magnetic stirring with subsequent pyrolysis treatment. The results showed that the morphology of carbon skeletons evolved from an irregular agglomerate to a uniform hexagonal star shape and then to an agglomerate again by reducing the molar ratio of Co2+ to Zn2+. Remarkably, excellent EMW absorption capacity in the Ku-band was achieved through carefully regulating the molar ratio of Co2+ to Zn2+. When the filling ratio was 20wt.%, the prepared Co/CoO/C composite exhibited the best EMW absorption performance with the minimum reflection loss of -64 dB at a thickness of 1.79mm and the maximum effective absorption bandwidth of 6GHz at a thickness of 2.14mm. Furthermore, the radar cross section in the far-field was simulated by computer simulation technique. In addition, the possible EMW attenuation mechanism was proposed. Therefore, the results of this paper could be helpful for developing carbon-based magnetic composites derived from MOFs as broadband and high-efficiency EMW absorbers.

Aqueous Photocatalytic Oxidation of Thioethers with Polydiacetylene Micelle Nanoreactors.

A semi-heterogeneous photocatalytic system was assembled through encapsulation of a lipophilic porphyrin in stabilized polydiacetylene micelles. The colloidal nanohybrid catalyst was valorized in the aerobic photo-oxidation of sulfides to the corresponding sulfoxides. Micelles behaved as nanoreactors by creating a favorable environment for the photo-activation of oxygen nearby thioethers and subsequent sulfoxidation. The process operates selectively under visible light and air atmosphere, with low catalytic loading and in water as the only solvent.

Corrigendum to “Co-doped hollow nanospheres with low Pt loading for electrocatalytic oxygen reduction and zinc-air batteries” [J. Electroanal. Chem. 967(2024) 118449

Corrigendum to “Co-doped hollow nanospheres with low Pt loading for electrocatalytic oxygen reduction and zinc-air batteries” [J. Electroanal. Chem. 967(2024) 118449

Anthropometric and Demographic Features Affect the Interpretation of Cerebrospinal Fluid Biomarkers in Patients with Different Dementia Syndromes and Cognitively Healthy Adults.

Clinical distinction between dementia with Lewy bodies (DLB) and late-onset Alzheimer's disease (AD) is difficult, while several features might affect the analyses of biomarkers. This study aimed to verify associations of anthropometric and demographic features with cerebrospinal fluid biomarkers, their ratios, and restructured traditional regression formulas in patients with DLB and AD, as well as in cognitively healthy controls. Consecutive outpatients with DLB were paired with outpatients with AD according to sex, dementia stage, and cognitive status, and with controls according to sex and age to investigate associations of sex, age, dementia duration, total sleep time, body mass index, alcohol use, smoking, sanitation, and APOE-ε4 alleles on the measurement of cerebrospinal fluid α-synuclein, biomarker ratios, and restructured traditional regression formulas involving amyloid-β (Aβ42,Aβ40,Aβ38), tau, and phospho-tau Thr181. Overall, 81 participants were included with DLB (n = 27;11 APOE-ε4 +) or AD (n = 27;12 APOE-ε4 +), and controls (n = 27;4 APOE-ε4 +); two thirds were women. Cerebrospinal fluid evidence of amyloidosis and tauopathy was more prevalent among women with AD, while Aβ42/Aβ38 could also discriminate men with DLB from men with AD. Restructured traditional regression formulas had higher diagnostic accuracy for women with AD. Aging, higher body mass index, and APOE-ε4 alleles were associated with amyloidosis in DLB, while only in AD were higher body mass index associated with lower tau pathology load, and more alcohol use associated with higher phospho-tau Thr181/Aβ42. These findings confirm the effects of anthropometric and demographic features on cerebrospinal fluid biomarkers, and also differences in aberrant amyloidosis and tauopathy between DLB and AD.

Leptospira Leptolysin Contributes to Serum Resistance but Is Not Essential for Acute Infection.

Previous invitro works focusing on virulence determinants of the spirochete Leptospira implicated metalloproteinases as putative contributing factors to the pathogenicity of these bacteria. Those proteins have the capacity to degrade extracellular matrix components (ECM) and proteins of host's innate immunity, notably effectors of the complement system. In this study, we gained further knowledge on the role of leptolysin, one of the leptospiral-secreted metalloproteinases, previously described as having a broad substrate specificity. We demonstrated that a proportion of human patients with mild leptospirosis evaluated in the current study produced antibodies that recognize leptolysin, thus indicating that the protease is expressed during host infection. Using recombinant protein and a knockout mutant strain, Manilae leptolysin-, we determined that leptolysin contributes to Leptospira interrogans serum resistance invitro, likely by proteolysis of complement molecules of the alternative, the classical, the lectin, and the terminal pathways. Furthermore, in a hamster model of infection, the mutant strain retained virulence; however, infected animals had lower bacterial loads in their kidneys. Further studies are necessary to better understand the role and potential redundancy of metalloproteinases on the pathogenicity of this important neglected disease.

Targeting dendritic cells to drive PDAC immunotherapy response

Pancreatic adenocarcinoma (PDAC) has been historically unresponsive to immunotherapy, predominantly due to lower antigen loads and lack of tumor-infiltrating dendritic cells (DCs) and T cells. A recent study by Mahadevan and colleagues demonstrates that increasing DC infiltration through use of an engineered DC1 vaccine can sensitize PDAC to immunotherapy.

Influencing Factors Analysis of Infectious SARS-CoV-2 Aerosols Sampling

Assessing the potential infectivity of airborne viruses is critical for evaluating the risk of their transmission through air. This study investigated the factors influencing the collection of infectious SARS-CoV-2 aerosols using three common aerosol samplers: the impactor sampler AGI-30, the SKC Biosampler, and a cyclone sampler WA-400III. It was found that the sampling process over time significantly impacted the infectivity of SARS-CoV-2 captured in the sampler, and the infectivity loss of different SARS-CoV-2 variants in the process varied. Additionally, adding newborn calf serum in the collection suspension could effectively preserve viral infectivity in the sampler. Further tests conducted under various ventilation occasions indicated that ventilation can reduce the virus concentration in the environment and rapidly clear viral particles after aerosol generation. Although the flow rate of WA-400III is higher, it only could collect higher concentrations of viral RNA instead of live viruses than AGI-30 or SKC Biosampler when aerosol was generated constantly in the environment. After aerosol generation stopped, the WA-400III collected more infectious viruses and viral RNA. This study highlights the impact of the sampling process on captured virus should be assessed and protective agent is needed to preserve viral viability. And it is crucial to select appropriate sampler based on environmental characteristics and research objectives for obtaining optimal results. The AGI-30 and SKC Biosampler are preferable for collecting infectious viruses in environments with high aerosol concentrations, while the cyclone sampler WA-400III is more effective for collecting viral nucleic acids and enriching virus samples in confined spaces with lower viral loads.

Efficiency of infrared pyrometer and infrared thermography for assessing body surface temperature in hair sheep

The objectives of this study were: (i) to verify and compare the coat surface temperature (CST) of regions of interest (ROI) measured through infrared pyrometer (IRP) and thermography (IRT) under two environmental conditions, to evaluate (ii) reliability and (iii) sensitivity of the two infrared equipments to the environmental effect. Twenty hair ewes (Ovis aries), multiparous, non-lactating, non-pregnant, with body weight 59.38 ± 6.23 kg and body score condition ranging from 2.5 to 4.5 were evaluated. All CST, in both infrared methods, were higher (P < 0.001) in the afternoon (2 to 3 p.m.), with the exception of eyes surface temperature (TSEY) from IRT, which was higher (P < 0.001) in the morning (8 to 9 a.m.). Regarding the infrared methods at different times (twice a day, morning and afternoon), of the day, CST values for all ROIs were significantly higher (P < 0.001) in thermography, regardless of the time shift, except for ear pinna surface temperature (TSE) and rectum surface temperature (TSR), which showed no significant difference (P > 0.05) between the infrared methods during the morning shift. The thermal environment significantly influences (P < 0.001) the surface temperature of various anatomical regions in both infrared methods. The correlation coefficients between IRT and IRP were moderate. The IRT is more sensitive to the thermal environment, as it presented higher canonical coefficients in the environmental variables. Among surface temperatures, eye surface temperature is the most influenced by variables in the thermal environment, especially THI. All three methods (digital thermometer-DT, IRT and IRP) showed >80 % of the data variation in the first two components. Using the DT, we observed an association between vaginal temperature (VT) and RT with air temperature (AT) and temperature humidity index (THI), which was similar to the infrared thermography pattern, in which all ROIs were highly correlated with AT and THI. The opposite was observed in the pyrometer, in which an association between eye temperature and RH and lower factor loadings of the other ROIs with AT and THI in the first component was observed. In conclusion, while IRP and IRT showed similar performance in the morning, IRT proved to be more accurate in the afternoon, demonstrating a higher success rate in classifying the group of origin. Therefore, it is concluded that IRT is more reliable than IRP in detecting surface temperature changes under high temperatures.

Enhancing understanding: Back muscle strength and individual flexibility impact on the flexion-relaxation phenomenon in the lumbar erector spinae

The flexion-relaxation phenomenon (FRP) refers to the deactivation of back muscles during deep forward trunk bending. This study examined the effects of back muscle strength, individual flexibility, and trunk angle on FRP in the back muscles. Forty male participants were classified into four groups according to toe-touch flexibility and back muscle strength. Lumbar erector spinae (LES) activity and the lumbosacral angle (LSA) were measured at incremental trunk flexion angles (0°–90°, with increments of 15°) to analyze FRP. Results indicated significant effects of back muscle strength, flexibility, and trunk angle on LES activity (all p < 0.001). Flexibility (p < 0.05) and trunk angle (p < 0.001) also influenced LSA. Additionally, an interaction between flexibility and trunk angle impacted LES activation (p < 0.001). Flexibility mainly determined FRP onset, while back muscle strength influenced efforts during moderate trunk flexion (30°–60°). These findings indicate that differences in lower back load among individuals with varying back muscle strengths become apparent even at relatively small trunk flexion angles (approximately 30°). When prolonged static trunk flexion in workplace settings places considerable strain on the lower back, we recommend utilizing toe-touch flexibility and back muscle strength assessments as practical screening tools for identifying early and subtle indicators of the FRP in workers.

Effect of Plant Identity in Wheat Mixtures on English Grain Aphid (Sitobion avenae) Control

ABSTRACTField experiments have demonstrated that wheat mixtures differ in their ability to regulate aphid populations. To further investigate the effectiveness of wheat mixtures (Triticum aestivum and Triticum turgidum) in controlling aphids, we conducted both laboratory and greenhouse experiments. Specifically, we assessed the associational resistance of two wheat mixtures (Florence‐Aurora with Forment, Florence‐Aurora with Montcada), and their respective monocultures, in different stages of the aphid host selection process. We analysed aphid acceptance rate, population growth, and load under different wheat treatments. Additionally, we characterised wheat aboveground biomass and nitrogen content as important functional traits for aphid resistant. Aphid acceptance decreased in plants of cv. Forment when exposed to volatiles from undamaged Florence‐Aurora plants, whereas the other tested combinations tested had no effect. Aphids performed differently in the two mixtures: Florence‐Aurora mixed with Forment significantly reduced aphid population growth and load compared to the monocultures, whereas the combination of Florence‐Aurora with Montcada wheat had no effect on aphid performance. The plant–plant interactions also modified the analysed traits. Nitrogen content of Florence‐Aurora wheat plants was reduced when mixed with Forment wheat, which may explain the lower aphid load observed in plants of cv. Florence‐Aurora when mixed with plants of cv. Forment. However, mixing wheats with similar aboveground biomass resulted in an increase in the average biomass of plants of both cultivars which could have led to a higher aphid population. The data supports the idea of right neighbour, as the benefits of wheat mixtures for aphid control were determined by the identity of the combined plants (or species). Finally, our results suggest that associating wheats with different traits may promote facilitative interactions, which in turn enhances associational resistance, whereas the combination of wheats with similar traits may result in competitive interactions that may hinder aphid control benefits.

Initial HIV-1 viral load in French Guiana: Factors associated with viral load set point differences.

Background. HIV viral load set points may vary between virus subtypes and host characteristics. The HIV epidemic in French Guiana entails a mix of viruses and populations of cosmopolitan origins. In this epidemiological context, we aimed to determine whether at the scale of our territory, we could identify differences in HIV-1 viral load setpoints in our hospital cohort. MethodsThe French Guiana hospital cohort was retrospectively analyzed between 1992 and 2023. Bootstrapped (100 replications) quantile (median) regression modelled the initial HIV-1 viral load with age, sex, nationality, and CD4 count at diagnosis as independent variables. ResultsAfter adjusting for period of analysis and CD4 count at diagnosis, bootstrapped quantile regression (median) showed that Haitians (minus 20 088 copies, P<0.0001) and Guyanese (minus 14087, P=0.039) had a significantly lower viral load at HIV diagnosis than French, males had a greater viral load at HIV diagnosis than females (plus 16 430 copies, P<0.0001), each additional year of age was associated with more copies (+345 per year, P=0.002). When compared to those with more than 500 CD4 per ml, persons with CD4 counts at diagnosis below 200 per ml had a greater initial viral load (plus 94 932 copies, P<0.0001), as did those with 200-350 CD4 per ml (plus 13 088 copies, P<0.0001), and those with [350-500 CD4 per ml] (plus 5 643 copies, P<0.0001). Non B viruses seemed to have an independently greater viral load at diagnosis than B viruses (plus 58402, P=0.029). Conclusions: We show some significant differences in the viral load set point of different groups. For nationalities we are inclined to attribute this to differences in the frequency of infecting subtypes. This suggests that models of incidence or date of infection based on CD4 decline may be distorted by this situation.

Finite element-based evaluation of the supraspinatus tendon biomechanical environment necessitates better clinical management based on tear location and thickness

Partial-thickness rotator cuff tears are a common cause of pain and disability and are central to developing full-thickness rotator cuff tears. However, limited knowledge exists regarding the alterations to the mechanical environment due to these lesions. Computational models that study the alterations to the mechanical environment of the supraspinatus tendon can help advance clinical management to avoid tear progression and provide a basis for surgical intervention. In this study, we use three-dimensional validated finite element models from six intact specimens to study the effects of low- and high-grade tears originating on the articular and bursal surfaces of the supraspinatus tendon. Bursal-sided tears generally had a lower failure load, modulus, and strain than articular-sided tears. Thus, caution should be taken when managing bursal-sided tears as they may be more susceptible to tear progression.