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Chitosan is a biopolymer that can be subjected to a variety of chemical modifications to generate new materials. The properties of modified chitosan are affected by its degree of deacetylation (DDA), which corresponds to the percentage of D-glucosamine monomers in its polymeric structure. Potentiometric titration is amongst the simplest, most readily available, and most cost-effective methods of determining the DDA. However, this method often suffers from a lack of precision, especially for modified chitosan resins. This is in large part because the equation used to calculate the DDA does not consider the molecular weight of the chemically modified monomeric units. In this paper, we introduce a new equation that is especially suited for modified chitosan bearing three different types of monomers. To test this equation, we prepared naphthalene–chitosan resins and subjected them to potentiometric titration. Our results show that our new equation, which is truer to the real structure of the polymeric chains, gives higher DDA values than those of the routinely used equations. These results show that the traditional equations underestimate the DDA of modified chitosan resins.

Chitosan is a linear biopolymer composed of D-glucosamine and N-acetylglucosamine units. The percentage of D-glucosamine in the polymeric chain can vary from one sample to another and is expressed as the degree of deacetylation (DDA). Since this parameter has an impact on many properties, its determination is often critical, and potentiometric titration is a common analytical technique to measure the DDA. Cross-linking with glutaraldehyde is one of the most explored modifications of chitosan; however, the determination of the DDA for the resulting reticulated chitosan resins can be challenging. In this paper, we report a new, rapid, and efficient method to determine the DDA of glutaraldehyde-cross-linked chitosan resins via HPLC. This method relies on the use of 2,4-dinitrophenylhydrazine (DNPH) as a derivatizing agent to measure the level of reticulation of the polymer (LR) after the reticulation step. In this study, we prepare three calibration curves (with an R2 value over 0.92) for three series of reticulated polymers covering a large range of reticulation levels to demonstrate that a correlation can be established between the LR established via HPLC and the DDA obtained via titration. The polymers are derived from three different chitosan starting materials. These standard calibration curves are now used on a routine basis in our lab, and the HPLC method has allowed us to change our DDA analysis time from 20 h to 5 min.

Laser-plasma accelerators emerge as ultra-compact and versatile sources for numerous applications. Although the acceleration length is short (a few millimeters), they typically require large-scale infrastructures including ultra-high-power lasers, vacuum chambers and strict stability for temperature and humidity. As a result, most experiments are conducted in laboratories in large areas with controlled environments. Here, we present a highly compact (footprint of ~ 9 m²) and transportable system capable of generating electrons and photons in the MeV range at high repetition rates (up to 10 Hz) with average charge levels of 0.5 nC and up to 1 nC. This achievement shows the feasibility of performing laser-plasma acceleration outside of laboratory environments with a transportable system, significantly expanding the potential for practical applications.

Is there truth in history? Historians are commonly expected to produce ‘facts’ and to be ‘objective’. If they teach the history of Christianity, their audience sees in them the depositors of the ‘truth’ on the history of church. Showing the contradictions of the church’s discourse in the past and highlighting the essentially transient nature of church doctrine are perceived as a threat. Yet, our knowledge of the Christian past is provisional and limited. It depends on the quality of the historical sources at our disposal. Consciously or not, it is always the result of a process of knowledge construction. The aim of this article is to explore the triple challenge – pedagogical, pastoral and intellectual – that researchers in history of Christianity face in the exercise of their profession. Historians trained in the tradition of historical criticism consider that an historical narrative can claim a certain degree of approximation of the truth if the documents on which it is based pass the test of authenticity, reliability and validity. Without necessarily denying that truth exists somehow and somewhere, postmodern historians – and this also applies to Christian history – insist that any form of historical knowledge is constructed and that all approaches to truth are situated in terms of period, geographical location, social environment, class, gender, age and race. The study of history of Christianity brings discomfort. But in the end, one gains from confronting the critical challenges of the discipline. Faith will come out stronger if it faces the reality of the human condition.

In October 1998, a think tank of the Rwandan state proposed the establishment of gacaca jurisdictions – popular courts charged with judging the people involved in the genocide against the Tutsi. Lesser known is the Christian gacaca, a conflict resolution mechanism, also inspired by the traditional gacaca, which was established during the same period by the Catholic Church of Rwanda as part of the synodal process leading to the celebration of the 2000 Year Jubilee. This essay describes, on the basis of archival documents and oral testimonies, the genesis of the Christian gacaca and examines how it related to the official gacaca. This pastoral initiative contributed to a relaxation of the tension between church and state that had marked the immediate aftermath of the genocide. The aim of the Christian gacaca was to bring about reconciliation in communities divided by the genocide, by bringing together victims and perpetrators. The task of the official gacaca was to judge and, if the guilt was established, to punish the authors of the genocide crimes. It was also, like in the Christian gacaca, to restore social harmony, but only through a judicial process.

Case presentation A 71-year-old male, previously diagnosed with non-Hodgkin lymphoma and myelodysplastic syndrome, was admitted to the infectious disease unit of our hospital due to suspected infection of a hematoma in the left deltoid muscle, following his fourth dose of the COVID-19 vaccine, with a fever of 38.7 recorded at arrival to the emergency department. [See PDF for image] Fig. 1 Necrotic lesions of both eyelids at the presentation Systemic treatment with piperacillin-tazobactam 4.5 g IV every 6 h was started. Unfortunately, this condition resulted in the loss of vision in his right eye. Early clinical recognition of this condition is crucial for timely management and improved patient outcomes.

Abstract TRUEFAD (TRUE Fiber Atrophy Distinction) is a bioimagery user-friendly tool developed to allow consistent and automatic measurement of myotube diameter in vitro, muscle fiber size and type using rodents and human muscle biopsies. This TRUEFAD package was set up to standardize and dynamize muscle research via easy-to-obtain images run on an open-source plugin for FIJI. We showed here both the robustness and the performance of our pipelines to correctly segment muscle cells and fibers. We evaluated our pipeline on real experiment image sets and showed consistent reliability across images and conditions. TRUEFAD development makes possible systematical and rapid screening of substances impacting muscle morphology for helping scientists focus on their hypothesis rather than image analysis.

Diabetic macular edema (DME) is a common complication of diabetic retinopathy. Treatment with intravitreal injections is effective in most cases but is associated with a high therapeutic burden for patients. This implies the need for long-term treatments, such as the fluocinolone acetonide (FAc) implant. A review of basic science, pharmacology, and clinical data was conducted to provide a state-of-the-art view of the FAc implant in 2024. Although generally well tolerated, the FAc implant has been associated with ocular hypertension and cataract, and caution should be advised to the patients in this regard. By synthesizing information across these domains, a comprehensive evaluation can be attained, facilitating informed decision-making regarding the use of the FAc implant in the management of DME. The main objective of this review is to provide clinicians with guidelines on how to introduce and use the FAc implant in a patient with DME.

To evaluate the correlation of retinal nerve fibre layer (RNFL) thickness measured using spectral domain optical coherence tomography (SD-OCT) and scanning laser polarimetry (SLP) in uveitic eyes compared with healthy eyes. A descriptive, observational, prospective, consecutive, cross-sectional, controlled, monocentre case series was conducted from May to October 2015. Clinical characteristics, best-corrected visual acuity, intraocular pressure, RNFL thickness measurement with SD-OCT and SLP using GDx variable corneal compensation (GDx VCC) were performed for each patient. An evaluation of anterior chamber inflammation with laser flare-cell meter was also carried out. Correlations between SD-OCT and GDx VCC RNFL measurement were evaluated by linear regression analysis. Fifty-four patients were included and divided into two groups: 50 healthy eyes in 29 patients and 42 uveitic eyes in 25 patients. The mean RNFL thickness was 98.08(±8.42) and 113.21(±20.53) μm in the healthy group and the uveitic group, respectively, when measured with SD-OCT (p<0.001); and 56.43(±5.24) and 58.77(±6.67) μm, respectively, when measured with GDx VCC (p=0.078). There was a strong correlation between total average RNFL thickness measured using SD-OCT and GDX (r=0.48, p<0.001) in healthy eyes but there was no correlation in the uveitic eyes (r=0.2, p=0.19). RNFL thickness was significantly greater when measured using SD-OCT in active uveitis as compared with GDx. There was no correlation between the RNFL thickness measurements obtained using the two techniques in uveitic eyes. The discrepancies between the results suggest that for these patients both techniques should be used in conjunction to obtain an accurate measurement of RNFL. IRB 00008855 Société Française d'Ophtalmologie IRB#1.

The deterioration of sleep in the older population is a prevalent feature that contributes to a decrease in quality of life. Inappropriate entrainment of the circadian clock by light is considered to contribute to the alteration of sleep structure and circadian rhythms in the elderly. The present study investigates the effects of aging on non-visual spectral sensitivity to light and tests the hypothesis that circadian disturbances are related to a decreased light transmittance. In a within-subject design, eight aged and five young subjects were exposed at night to 60 minute monochromatic light stimulations at 9 different wavelengths (420–620 nm). Individual sensitivity spectra were derived from measures of melatonin suppression. Lens density was assessed using a validated psychophysical technique. Although lens transmittance was decreased for short wavelength light in the older participants, melatonin suppression was not reduced. Peak of non-visual sensitivity was, however, shifted to longer wavelengths in the aged participants (494 nm) compared to young (484 nm). Our results indicate that increased lens filtering does not necessarily lead to a decreased non-visual sensitivity to light. The lack of age-related decrease in non-visual sensitivity to light may involve as yet undefined adaptive mechanisms.