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Optical tweezers are tools made of light that enable contactless pushing, trapping, and manipulation of objects, ranging from atoms to space light sails. Since the pioneering work by Arthur Ashkin in the 1970s, optical tweezers have evolved into sophisticated instruments and have been employed in a broad range of applications in the life sciences, physics, and engineering. These include accurate force and torque measurement at the femtonewton level, microrheology of complex fluids, single micro- and nano-particle spectroscopy, single-cell analysis, and statistical-physics experiments. This roadmap provides insights into current investigations involving optical forces and optical tweezers from their theoretical foundations to designs and setups. It also offers perspectives for applications to a wide range of research fields, from biophysics to space exploration.

This article studies the fatigue behavior of the Al-5wt%Si-2.5wt%Cu alloy. The effect of combining techniques of chemical grain refining (Al-5wt%Ti-1wt%B alloy) added to electromagnetic stirring, CGR+EMS, is demonstrated in this work. This combination produced a microstructure with reduced grain size (121 ± 20 µm) when compared with the raw material produced only by electromagnetic stirring, EMS, (213 ± 38µm), with grain refiner Only, CGR, (184 ± 23 µm) or Without any Grain Refining Technique (WGRT) (413 ± 96 µm). The condition produced by associating electromagnetic stirring with the Al-5wt%Ti-1wt%B grain refiner presented the smallest grain size and less porosity. Thus, conditions CGR+EMS and WGRT were chosen to continue the evaluation of the mechanical performance of the studied alloy via tensile tests, whose results for ultimate tensile stress, yield strength and elongation were, respectively, WGRT/ CGR+EMS, UTS = 160.3 ± 9.5 / 208 ± 10 MPa, YS (0.2%) = 110 ± 2 / 135 ± 3.5 MPa and ε(%) =3.2 ± 0.1 / 2.9 ± 0.1. Fatigue tests were conducted via the staircase method. The average estimate of fatigue strength for a given life (107 cycles) and the standard deviation calculated for WGRT and CGR+EMS condition were, respectively, μ ^ y = 60.1 MPa / 71.6 MPa and σ ^ y= 3.30 / 6.42.

Optical tweezers are tools made of light that enable contactless pushing, trapping, and manipulation of objects, ranging from atoms to space light sails. Since the pioneering work by Arthur Ashkin in the 1970s, optical tweezers have evolved into sophisticated instruments and have been employed in a broad range of applications in the life sciences, physics, and engineering. These include accurate force and torque measurement at the femtonewton level, microrheology of complex fluids, single micro- and nano-particle spectroscopy, single-cell analysis, and statistical-physics experiments. This roadmap provides insights into current investigations involving optical forces and optical tweezers from their theoretical foundations to designs and setups. It also offers perspectives for applications to a wide range of research fields, from biophysics to space exploration.

We report analytical expressions for optical forces acting on particles inside waveguides. The analysis builds on our previously reported Fourier Transform method to obtain Beam Shape Coefficients for any beam. Here we develop analytical expressions for the Beam Shape Coefficients in cylindrical and rectangular metallic waveguides. The theory is valid for particle radius a ranging from the Rayleigh regime to large microparticles, such as aerosols like virus loaded droplets. The theory is used to investigate how optical forces within hollow waveguides can be used to sort particles in “optical chromatography” experiments in which particles are optically propelled along a hollow-core waveguide. For Rayleigh particles, the axial force is found to scale with a6, while the radial force, which prevents particles from crashing into the waveguide walls, scales with a3. For microparticles, narrow Mie resonances create a strong wavelength dependence of the optical force, enabling more selective sorting. Several beam parameters, such as power, wavelength, polarization state and waveguide modes can be tuned to optimize the sorting performance. The analysis focuses on cylindrical waveguides, where meter-long liquid waveguides in the form of hollow-core photonic crystal fibers are readily available. The modes of such fibers are well-approximated by the cylindrical waveguide modes considered in the theory.

Vitamin K sequentially undergoes -oxidation followed by successive rounds of ß-oxidation to ultimately produce two chainshortened carboxylic acid metabolites, vitamin K acid 1 and vitamin K acid 2. Two facile syntheses of these acid metabolites are described, each starting from the same commercially available menadione-cyclopentadiene adduct. Vitamin K acid 1 was synthesized in five steps via alkylation with geranyl bromide followed by subsequent oxidation reactions, while fully retaining the trans-configuration of the side chain 2',3'-double bond. Vitamin K acid 2 was synthesized in five steps via alkylation with dimethylallyl chloride and subsequent oxidation reactions. [ABSTRACT FROM AUTHOR]

The objective of the study was the analysis of clinical types, outcomes, and risk factors associated with the outcome of adenovirus (ADV) infection, in children and adults after allo-HCT. A total number of 2529 patients (43.9% children; 56.1% adults) transplanted between 2000 and 2022 reported to the EBMT database with diagnosis of ADV infection were analyzed. ADV infection manifested mainly as viremia (62.6%) or gastrointestinal infection (17.9%). The risk of 1-year mortality was higher in adults (p = 0.0001), and in patients with ADV infection developing before day +100 (p < 0.0001). The 100-day overall survival after diagnosis of ADV infections was 79.2% in children and 71.9% in adults (p < 0.0001). Factors contributing to increased risk of death by day +100 in multivariate analysis, in children: CMV seropositivity of donor and/or recipient (p = 0.02), and Lansky/Karnofsky score <90 (p < 0.0001), while in adults: type of ADV infection (viremia or pneumonia vs gastrointestinal infection) (p = 0.0004), second or higher HCT (p = 0.0003), and shorter time from allo-HCT to ADV infection (p = 0.003). In conclusion, we have shown that in patients infected with ADV, short-term survival is better in children than adults. Factors directly related to ADV infection (time, clinical type) contribute to mortality in adults, while pre-transplant factors (CMV serostatus, Lansky/Karnofsky score) contribute to mortality in children., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

Listeriosis is rare after hematopoietic stem cell transplantation (HCT). Little is known about listeriosis in this population. In this retrospective international case-control study, we evaluated 41 listeriosis episodes occurring between 2000 and 2021 in HCT recipients (111 transplant centers in 30 countries) and assessed risk factors for listeriosis by comparisons with matched controls. The 41 listeriosis episodes (all due to Listeria monocytogenes [LM]) occurred in 30 allogeneic (allo)-HCT recipients and 11 autologous (auto)-HCT recipients at a median of 6.2 months (interquartile range [IQR], 1.6 to 19.3 months) post-HCT. The estimated incidence was 49.8/100,000 allo-HCT recipients and 13.7/100,000 auto-HCT recipients. The most common manifestations in our cohort were fever (n = 39; 95%), headache (n = 9; 22%), diarrhea, and impaired consciousness (n = 8 each; 20%). Four patients (10%) presented with septic shock, and 19 of 38 (50%) were severely lymphocytopenic. Thirty-seven patients (90%) had LM bacteremia. Eleven patients (27%) had neurolisteriosis, of whom 4 presented with nonspecific signs and 5 had normal brain imaging findings. Cerebrospinal fluid analysis revealed high protein and pleocytosis (mainly neutrophilic). Three-month mortality was 17% overall (n = 7), including 27% (n = 3 of 11) in patients with neurolisteriosis and 13% (n = 4 of 30) in those without neurolisteriosis. In the multivariate analysis comparing cases with 74 controls, non-first HCT (odds ratio [OR], 5.84; 95% confidence interval [CI], 1.10 to 30.82; P = .038); and lymphocytopenia <500 cells/mm 3 (OR, 7.54; 95% CI, 1.50 to 37.83; P = .014) were significantly associated with listeriosis. There were no statistically significant differences in background characteristics, immunosuppression, and cotrimoxazole prophylaxis between cases and controls. HCT recipients are at increased risk for listeriosis compared to the general population. Listeriosis cause severe disease with septic shock and mortality. Neurolisteriosis can present with nonspecific signs and normal imaging. Lymphocytopenia and non-first HCT are associated with an increased risk of listeriosis, and cotrimoxazole was not protective., (Copyright © 2024 The American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc. All rights reserved.)

Objectives: Nocardiosis is a rare but life-threatening infection after hematopoietic cell transplantation (HCT). We aimed at identifying risk factors for nocardiosis after allogeneic HCT and clarifying the effect of trimethoprim-sulfamethoxazole prophylaxis on its occurrence., Methods: We performed a retrospective multicenter case-control study of patients diagnosed with nocardiosis after allogeneic HCT between January 2000 and December 2018. For each case, two controls were matched by center, transplant date, and age group. Multivariable analysis was conducted using conditional logistic regression to identify potential risk factors for nocardiosis. Kaplan-Meier survival curves of cases and controls were compared using log-rank tests., Results: Sixty-four cases and 128 controls were included. Nocardiosis occurred at a median of 9 months after allogeneic HCT (interquartile range: 5-18). After adjustment for potential confounders in a multivariable model, Nocardia infection was associated with tacrolimus use (adjusted odds ratio [aOR] 9.9, 95 % confidence interval [95 % CI]: 1.6-62.7), lymphocyte count < 500/µL (aOR 8.9, 95 % CI: 2.3-34.7), male sex (aOR 8.1, 95 % CI: 2.1-31.5), recent use of systemic corticosteroids (aOR 7.9, 95 % CI: 2.2-28.2), and recent CMV infection (aOR 4.3, 95 % CI: 1.2-15.9). Conversely, use of trimethoprim-sulfamethoxazole prophylaxis was associated with a significantly decreased risk of nocardiosis (aOR 0.2, 95 % CI: 0.1-0.8). HCT recipients who developed nocardiosis had a significantly decreased survival, as compared with controls (12-month survival: 58 % and 90 %, respectively; p < 0.0001)., Conclusions: We identified six factors independently associated with the occurrence of nocardiosis among allogeneic HCT recipients. In particular, trimethoprim-sulfamethoxazole prophylaxis was found to protect against nocardiosis., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Background: Home oxygen therapy (HOT) improves survival in patients with hypoxaemic chronic respiratory disease. Most patients evaluated for HOT are former or active smokers. Oxygen accelerates combustion and smoking may increase the risk of burn injuries and fire hazards; therefore, it is considered a contraindication for HOT in many countries. However, there is variability in the practices and policies regarding this matter. This multidisciplinary Swedish taskforce aimed to review the potential benefits and risks of smoking in relation to HOT, including medical, practical, legal and ethical considerations., Methods: The taskforce of the Swedish Respiratory Society comprises 15 members across respiratory medicine, nursing, medical law and ethics. HOT effectiveness and adverse risks related to smoking, as well as practical, legal and ethical considerations, were reviewed, resulting in five general questions and four PICO (population-intervention-comparator-outcome) questions. The strength of each recommendation was rated according to the GRADE (grading of recommendation assessment, development and evaluation) methodology., Results: General questions about the practical, legal and ethical aspects of HOT were discussed and summarised in the document. The PICO questions resulted in recommendations about assessment, management and follow-up of smoking when considering HOT, if HOT should be offered to people that meet the eligibility criteria but who continue to smoke, if a specific length of time of smoking cessation should be considered before assessing eligibility for HOT, and identification of areas for further research., Conclusions: Multiple factors need to be considered in the benefit/risk evaluation of HOT in active smokers. A systematic approach is suggested to guide healthcare professionals in evaluating HOT in relation to smoking., Competing Interests: Conflict of interest: The authors have no conflict of interest relevant for this study to declare., (Copyright ©The authors 2024.)

Background: Human metapneumovirus (hMPV) epidemiology, clinical characteristics and risk factors for poor outcome after allogeneic stem cell transplantation (allo-HCT) remain a poorly investigated area., Methods: This retrospective multicenter cohort study examined the epidemiology, clinical characteristics, and risk factors for poor outcomes associated with human metapneumovirus (hMPV) infections in recipients of allo-HCT., Results: We included 428 allo-HCT recipients who developed 438 hMPV infection episodes between January 2012 and January 2019. Most recipients were adults (93%). hMPV infections were diagnosed at a median of 373 days after allo-HCT. The infections were categorized as upper respiratory tract disease (URTD) or lower respiratory tract disease (LRTD), with 60% and 40% of cases, respectively. Patients with hMPV LRTD experienced the infection earlier in the transplant course and had higher rates of lymphopenia, neutropenia, corticosteroid use, and ribavirin therapy. Multivariate analysis identified lymphopenia and corticosteroid use (>30 mg/d) as independent risk factors for LRTD occurrence. The overall mortality at day 30 after hMPV detection was 2% for URTD, 12% for possible LRTD, and 21% for proven LRTD. Lymphopenia was the only independent risk factor associated with day 30 mortality in LRTD cases., Conclusions: These findings highlight the significance of lymphopenia and corticosteroid use in the development and severity of hMPV infections after allo-HCT, with lymphopenia being a predictor of higher mortality in LRTD cases., Competing Interests: Potential conflicts of interest. P. B. declares research grants from Neovii, Riemser, and Medac (to institution); advisory board membership for Novartis, Cellgene, Amgen, Medac, and Servier (personal and to institution); speakers bureau for Miltenyi, Jazz, Riemser, Novartis, and Amgen (to institution); and patent und royalties from Medac. All other authors report no potential conflicts. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed., (© The Author(s) 2023. Published by Oxford University Press on behalf of Infectious Diseases Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The aim of this study was to determine the current approach of EBV-driven post-transplant complications in context of monitoring, diagnosis, prevalence and treatment in EBMT transplant centers. Routine serology testing in patient and donor before HCT is performed in 95.5% centers. Pretransplant EBV-DNA is routinely tested in all patients in 32.7% centers. Monitoring for EBV infection is feasible in 98.2% centers: including 66.7% centers using standardized PCR. Post-HCT regular monitoring is performed in all patients in 80.5% centers. Anti-EBV prophylaxis with rituximab is used in 12.4% centers. Frequency of csEBV-DNA-emia was 7.4% (adults: 6.2%, children: 12.6%). The PCR threshold used to start preemptive treatment was differentiated among centers. Frequency of EBV-PTLD was 1.6% (adults: 1.3%; children: 3.5%). First-line therapy of EBV-driven complications was rituximab and reduction of immunosuppressive therapy. The rate of failure of first-line preemptive treatment was 12.0%. EBV-specific viral-specific T-lymphocytes were available in 46.0% centers. A number of new experimental therapies were given in 28 patients with resistant/refractory PTLD. In conclusion, the prevalence of EBV-DNA-emia and EBV-PTLD over the period 2020-2021 decreased in comparison to historical data. New trends (routine pretransplant screening for EBV-DNA, wider access to VST, new experimental therapies) are being observed in management of EBV infection after allo-HCT., (© 2023. The Author(s), under exclusive licence to Springer Nature Limited.)

Background: Infections are the main reason for mortality during acute leukaemia treatment and invasive aspergillosis (IA) is a major concern. Allogeneic stem cell transplantation (alloSCT) is a standard therapy and often is the only live-saving procedure in leukaemia patients. The profound immunodeficiency occurring after alloSCT led to high IA-associated mortality in the past. Therefore, patients with IA were historically considered transplant-ineligible. Recently, there has been improvement of anti-fungal management including novel anti-fungal agents. As a result, more leukaemia patients with IA are undergoing alloSCT. Outcome has not been prospectively assessed., Methods: We performed a prospective study in acute leukaemia patients undergoing alloSCT to analyse the impact of a prior history of probable or proven IA (pre-SCT IA). The primary endpoint was 1-year non-relapse mortality (NRM). Relapse free survival and overall survival were analysed as secondary endpoints., Findings: 1439 patients were included between 2016 and 2021. The incidence of probable or proven pre-SCT IA was 6.0% (n = 87). The cumulative incidence of 1-year NRM was 17.3% (95% CI 10.2-26.0) and 11.2% (9.6-13.0) for patients with and without pre-SCT IA. In multivariate analyses the hazard ratio (HR) for 1-year NRM was 2.1 (1.2-3.6; p = 0.009) for patients with pre-SCT IA. One-year relapse-free survival was inferior in patients with pre-SCT IA (59.4% [48.3-68.9] vs. 70.4 [67.9-72.8]; multivariate HR 1.5 [1.1-2.1]; p = 0.02). Consequently, 1-year overall survival was lower in patients with pre-SCT IA: (68.8% [57.8-77.4] vs. 79.0% [76.7-81.1]; multivariate HR 1.7 [1.1-2.5]; p = 0.01)., Interpretation: Pre-SCT IA remains to be significantly associated with impaired alloSCT outcome. On the other hand, more than two thirds of patients with pre-SCT IA were alive at one year after alloSCT. IA is not anymore an absolute contraindication for alloSCT because the majority of patients with IA who undergo alloSCT benefit from this procedure., Funding: There was no external funding source for this study., Competing Interests: R.dlC. Has received honoraria from Pfizer and MSD; J.S. reports personal fees from Gilead, outside the submitted work. EDK reports grants from Gilead sciences, personal fees from Pfizer, outside the submitted work. L.Y. reports grants and personal fees from Janssen, personal fees from Abbvie, personal fees and non-financial support from AstraZeneca, personal fees and non-financial support from Beigene, personal fees and non-financial support from Kite/Gilead, personal fees and non-financial support from Pfizer, outside the submitted work; S.M reports other from Celgene/BMS, other from Novartis, other from Kite/Gilead, other from Pfizer, other from Miltenyi, other from Mendes, other from SWECARNET, other from Scientify Research, outside the submitted work; J.M. reports personal fees and non-financial support from Gilead Sciences, personal fees and non-financial support from Mundipharma, personal fees and non-financial support from F2G, personal fees and non-financial support from Takeda, personal fees and non-financial support from Basilea, outside the submitted work; M.M. reports grants and personal fees from Gilead, personal fees from Mundipharma, personal fees from Pfizer, from null, outside the submitted work; H.P. reports non-financial support from Neovii, during the conduct of the study; OP has no COIs directly related to this work. HP reports non-financial support from Neovii during the conduct of the study; OP has received honoraria or travel support from Gilead, Jazz, MSD, Neovii, Novartis, Pfizer and Therakos. He has received research support from Incyte and Priothera. He is member of advisory boards to Equillium Bio, Jazz, Gilead, Novartis, MSD, Omeros, Orca Bio, Priothera, Sanofi, Shionogi and SOBI. T.Z. reports personal fees from AbbVie, personal fees from Orgenesis Inc, personal fees from BioSight Ltd, personal fees from Cellect Biotechnology, personal fees from Janssen, personal fees from Novartis, personal fees from Gilead Sciences, outside the submitted work. The remaining authors declare no conflict of interests., (© 2023 The Authors.)

We previously analyzed trends in incidence and factors associated with lethal complications in ALL/AML/CML patients (causes of deaths; COD-1 study). The objective of this study was the analysis of incidence and specific causes of death after HCT, with focus on infectious deaths in two time periods, 1980-2001 (cohort-1) and 2002-2015 (cohort-2). All patients with HCT for lymphoma, plasma cell disorders, chronic leukemia (except CML), myelodysplastic/myeloproliferative disorders, registered in the EBMT-ProMISe-database were included (n = 232,618) (COD-2 study). Results were compared to those in the ALL/AML/CML COD-1 study. Mortality from bacterial, viral, fungal, and parasitic infections decreased in very early, early and intermediate phases. In the late phase, mortality from bacterial infections increased, while mortality from fungal, viral, or unknown infectious etiology did not change. This pattern was similar for allo- and auto-HCT in COD-1 and COD-2 studies, with a distinct and constant lower incidence of all types of infections at all phases, after auto-HCT. In conclusion, infections were the main cause of death before day +100, followed by relapse. Mortality from infectious deaths significantly decreased, except late phase. Post-transplant mortality has significantly decreased in all phases, from all causes after auto-HCT; it has decreased in all phases after allo-HCT except late phase., (© 2023. The Author(s), under exclusive licence to Springer Nature Limited.)