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1.
Nanoscale Adv ; 6(10): 2629-2635, 2024 May 14.
Article in English | MEDLINE | ID: mdl-38752145

ABSTRACT

CVD graphene layers are intrinsically polycrystalline; depending on grain size, their structure at the atomic level is scarcely free of defects, which affects the properties of graphene. On the one hand, atomic-scale defects act as scattering centers and lead to a loss of carrier mobility. On the other hand, structural disorder at grain boundaries provides additional resistance in series that affects material conductivity. Graphene chemical functionalization has been demonstrated to be an effective way to improve its conductivity mainly by increasing carrier concentration. The present study reports the healing effects of sulfur doping on the electrical transport properties of single-layer CVD graphene. A post-growth thermal sulfurization process operating at 250 °C is applied on single layers of graphene on Corning-glass and Si/SiO2 substrates. XPS and Raman analyses reveal the covalent attachment of sulfur atoms in graphene carbon lattice without creating new C-sp3 defects. Measurements of transport properties show a significant improvement in hole mobility as revealed by Hall measurements and related material conductivity. Typically, Hall mobility values as high as 2500 cm2 V-1 s-1 and sheet resistance as low as 400 Ohm per square are measured on single-layer sulfurized graphene.

2.
Cancers (Basel) ; 16(10)2024 May 12.
Article in English | MEDLINE | ID: mdl-38791928

ABSTRACT

Surgical resection is the gold standard for treating synchronous colorectal liver metastases (CRLM). The resection of the primary tumor and metastatic lesions can follow different sequences: "simultaneous", "bowel-first", and "liver-first". Conservative approaches, such as parenchymal-sparing surgery and segmentectomy, may serve as alternatives to major hepatectomy. A comprehensive search of Medline, Epistemonikos, Scopus, and the Cochrane Library was conducted. Studies evaluating patients who underwent surgery for CRLM and reported survival results were included. Other secondary outcomes were analyzed, including disease-free survival, perioperative complications and mortality, and recurrence rates. Quality assessment was performed using the AMSTAR-2 method. No significant differences in overall survival, disease-free survival, and secondary outcomes were observed when comparing simultaneous to "bowel-first" resections, despite a higher rate of perioperative mortality in the former group. The 5-year OS was significantly higher for simultaneous resection compared to "liver-first" resection. No significant differences in OS and DFS were noted when comparing "liver-first" to "bowel-first" resection, or anatomic to non-anatomic resection. Our umbrella review validates simultaneous surgery as an effective oncological approach for treating SCRLM, though the increased risk of perioperative morbidity highlights the importance of selecting suitable patients. Non-anatomic resections might be favored to preserve liver function and enable future surgical interventions.

3.
J Clin Med ; 13(6)2024 Mar 21.
Article in English | MEDLINE | ID: mdl-38542027

ABSTRACT

Cholangiopathies include a group of chronic progressive disorders, affecting the cholangiocytes, the epithelial cells that line the biliary tree, leading to liver parenchymal fibrosis and eventually end-stage liver disease necessitating transplantation. Experimental modeling of these multifactorial cholestatic diseases faces challenges due to the lack of adequate experimental in vitro and in vivo models. A novel approach employs three-dimensional organoid systems that offer several advantages for modeling disease and testing drug response in vitro. Organoids mimic intercellular communication, replicate the architecture of organs, and maintain the cell's original phenotype. Cholangiocyte organoids provide an in vitro model to study the pathogenesis and pharmacotherapeutic treatment of cholangiopathies and show great promise for regenerative therapies. In particular, patient-derived organoids allow personalized medicine approaches and the study of individual disease characteristics. This review highlights the significance of cholangiocyte organoid models in advancing our understanding of cholangiopathies and driving advancements in regenerative medicine strategies.

4.
Rejuvenation Res ; 27(2): 75-80, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38386495

ABSTRACT

Since the association between frailty and difficulty in finding venous access (VA) is largely unexplored and unclear in geriatrics, the aim of this study is to demonstrate how multidimensional frailty is associated with bad VA in a population of older hospitalized people. Multidimensional Prognostic Index (MPI), based on eight different domains usually assessed in comprehensive geriatric assessment, was used for identifying multidimensional frailty; VA heritage was investigated using a questionnaire prepared by a trained nurse, based on clinical experience. Overall, 145 patients were included (mean age 78.6 ± 7.6; males 51.0%). Frailer people, identified as an MPI >0.66 (MPI 3), had a significantly higher presence of bad VA (49.0% vs. 27.3% in MPI 3 and MPI 1 groups, p = 0.045), no success at first attempt (49.0% vs. 22.7% in MPI 3 and MPI 1 groups, p = 0.03), reported more frequently pain during VA attempts (63.3% in MPI 3 vs. 27.3 in MPI 1, p = 0.002), and significantly higher scores in the Numeric Rating Scale compared to their robust counterparts. Taking robust participants in MPI 1 as reference, after adjusting for potential confounders, frailer people (MPI 3) were at increased odds of bad VA (odds ratio [OR] = 2.72; 95% confidence interval [CI]: 1.16-6.41; p = 0.02), not success at first attempt (OR = 3.67; 95% CI: 1.09-12.57; p = 0.04), and presence of pain during VA attempt (OR = 4.26; 95% CI: 1.30-13.92; p = 0.02). In conclusion, our study demonstrated an association between multidimensional frailty and bad VA in a population of older hospitalized people.


Subject(s)
Frailty , Male , Humans , Aged , Aged, 80 and over , Retrospective Studies , Prognosis , Pain , Geriatric Assessment/methods
5.
Int J Surg ; 110(1): 431-440, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-37800567

ABSTRACT

BACKGROUND: Liver transplantation (LT) is the gold standard for end-stage liver disease, yet postoperative complications challenge patients and physicians. Indocyanine green (ICG) clearance, a quantitative dynamic test of liver function, is a rapid, reproducible, and reliable test of liver function. This study aimed to systematically review and summarize current literature analyzing the association between ICG tests and post-LT outcomes. METHODS: This systematic review was conducted according to PRISMA guidelines. MEDLINE and Cochrane Library, as main databases, and other sources were searched until August 2022 to identify articles reporting the prognostic value of postoperative ICG tests associated with outcomes of adult LT recipients.Risk of bias of included articles was assessed using Quality In Prognosis Studies tool. Methodological quality varied from low to high across risk of bias domains. RESULTS: Six studies conducted between 1994 and 2018 in Europe, America, and Asia were included. The study population ranged from 50 to 332 participants. ICG clearance on the first postoperative day was associated with early allograft dysfunction, graft loss, 1-month and 3-month patient survival probability, prolonged ICU, and hospital stay. The dichotomized ICG plasma disappearance rate (PDR) provided a strong association with medium-term and long-term outcomes: PDR less than 10%/min with 1-month mortality or re-transplantation (odds ratio: 7.89, 95% CI 3.59-17.34, P <0.001) and PDR less than 16.0%/min with 3-month patient survival probability (hazard ratio: 13.90, 95% CI 4.67-41.35, P <0.01). The preoperative model for end-stage liver disease and body mass index were independent prognostic factors for early allograft dysfunction, early complications, and prolonged ICU stay; post-LT prothrombin time and INR were independently associated with graft loss and bilirubin with a prolonged hospital stay. CONCLUSION: This review shows that ICG clearance tests are associated with graft function recovery, suggesting that a potential prognostic role of ICG test, as an aid in predicting the post-LT course, could be considered.


Subject(s)
End Stage Liver Disease , Liver Transplantation , Adult , Humans , Indocyanine Green , Liver Transplantation/adverse effects , End Stage Liver Disease/etiology , Severity of Illness Index , Prognosis , Coloring Agents
7.
Cancers (Basel) ; 15(23)2023 Nov 26.
Article in English | MEDLINE | ID: mdl-38067299

ABSTRACT

Hepatocellular carcinoma (HCC) is a growing indication for liver transplantation (LT). Careful candidate selection is a prerequisite to keep post-LT recurrence rates within acceptable percentages. In the pre-LT period, various types of locoregional treatments and/or systemic therapies can be used for bridging or downstaging purposes. In this context, one of the factors limiting the possibility of treatment is the degree of functional liver impairment. In the LT subject, no widely accepted indications are available to guide treatment of disease recurrence and heterogeneity exists between transplant centers. Improved liver function post LT makes multiple therapeutic strategies theoretically feasible, but patient management is complicated by the need to adjust immunosuppressive therapy and to assess potential toxicities and drug-drug interactions. Finally, there is controversy and uncertainty about the use of recently introduced immunotherapeutic drugs, mainly due to the risk of organ rejection. In this paper, we will review the most recent available literature on the management of post-transplant HCC recurrence, discussing evidence and controversies.

8.
Updates Surg ; 75(8): 2075-2083, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37695503

ABSTRACT

Increasing organ shortage results in extended criteria donors (ECD) being used to face the growing demand for liver grafts. The demographic change leads to greater use of elderly donors for liver transplantation, historically considered marginal donors. Age is still considered amongst ECD in liver transplantation as it could affect transplant outcomes. However, what is the cutoff for donor age is still unclear and debated. A search of PubMed, Scopus and Cochrane Library was performed. The primary outcome was 1-year graft survival (GS). The secondary outcome was overall biliary complications and 3-5 years of graft and overall survival. A meta-regression model was used to analyse the temporal trend relation in the survival outcome. The meta-analysis included 11 studies. Hazard ratios for 1-year (age cutoff of 70 and 80,) and 5-year GS (I2:0%) were similar irrespectively of the age group. The meta-regression analysis showed a significant correlation between the 1-year graft survival and the year of publication. (coef. 0.00027, 95% CI - 0.0001 to - 0.0003 p = 0.0009). Advanced-age donors showed an increased risk of overall biliary complications with an odd ratio (OR) of 1.89 (95% CI 1-3.65). Liver grafts potentially discharged because of high-risk failure show encouraging results, and GS in ECD has progressively improved with a temporal trend. Currently, the criteria of marginality vary amongst centres. Age alone cannot be considered amongst the extended criteria. First of all, because of the positive results in terms of septuagenarian graft survival. Moreover, the potential elderly donor-related adjunctive risk can be balanced by reducing other risk factors. A prospective multicentre study should investigate a multi-factorial model based on donor criteria, recipient features and new functional biomarkers to predict graft outcome, as proper donor-recipient matching seems to be the critical point for good outcomes.


Subject(s)
Liver Transplantation , Tissue and Organ Procurement , Humans , Aged , Liver Transplantation/methods , Prospective Studies , Tissue Donors , Graft Survival , Liver , Treatment Outcome , Retrospective Studies , Age Factors , Multicenter Studies as Topic
9.
Antibiotics (Basel) ; 12(9)2023 Aug 31.
Article in English | MEDLINE | ID: mdl-37760692

ABSTRACT

Background: Extracorporeal therapies (ET) are increasingly used in pediatric settings as adjuvant therapeutic strategies for overwhelming inflammatory conditions. Although these treatments seem to be effective for removing inflammatory mediators, their influence on antimicrobials pharmacokinetic should not be neglected. Methods: A prospective observational study of children admitted to the pediatric intensive care unit (PICU) with a diagnosis of sepsis/septic shock. All critically ill children received hemoadsorption treatment with CytoSorb (CS) in combination with CKRT. Therapeutic drug monitoring has been performed on 10 critically ill children, testing four antimicrobial molecules: meropenem, ceftazidime, amikacin and levofloxacin. In order to evaluate the total and isolated CKRT and CS contributions to antibiotic removal, blood samples at each circuit point (post-hemofilter, post-CS and in the effluent line) were performed. Therefore, the clearance and mass Removal (MR) of the hemofilter and CS were calculated. Results: Our preliminary report describes a different impact of CS on these target drugs removal: CS clearance was low for amikacine (6-12%), moderate for ceftazidime (43%) and moderate to high for levofloxacine (52-72%). Higher MR and clearance were observed with CKRT compared to CS. To the best of our knowledge, this is the first report regarding pharmacokinetic dynamics in critically ill children treated with CKRT and CS for septic shock.

10.
J Clin Med ; 12(13)2023 Jun 21.
Article in English | MEDLINE | ID: mdl-37445235

ABSTRACT

BACKGROUND: Dual mobility (DM) has been proven to reduce dislocation risk after total hip arthroplasty (THA). In the last decade modular DM (modDM) constructs have been introduced to allow the use of DM articulation with standard cementless acetabular shells. However, clinical evidence of modDM effectiveness is still low in primary THA and concerns about implant-related complications are increasing. This retrospective comparative multicenter study is aimed to investigate if the dislocation rate after primary THA could be reduced with modDM in comparison to standard bearing (SB). METHODS: 262 THAs were performed between 2017 and 2019, using SB (129 hips) or modDM (133) with the same cementless highly porous modular acetabular cup. Dislocations, complications and revisions were recorded and implant survival was analyzed. RESULTS: At 2.5-year mean follow-up, dislocation occurred in 4 hips (3.1%) within the SB group while intraprosthetic dislocation in 2 hips (1.5%) within the modDM group (p = 0.44). Implant survivals with revision due to dislocation were 95.2% and 95.9% at 4-year follow-up for SB and modDM, respectively (p = 0.50). CONCLUSIONS: modDM used in primary THA might reduce dislocation rate in comparison to SB, even in high-risk patients, however, caution is advocated due to specific intraprosthetic dislocation.

11.
Sci Rep ; 13(1): 4920, 2023 Mar 25.
Article in English | MEDLINE | ID: mdl-36966206

ABSTRACT

We propose and numerically investigate a smart, optically transparent digital metasurface reflective in the mmWave range, based on CVD graphene programmable elements. For both TM and TE polarizations, we detail the optimization of the unit cells, designed to exhibit two distinct states that correspond to those of binary encoding. The whole metasurface encoding can be customized to provide different electromagnetic functions, such as wide-band beam splitting at a controlled angle and reduction of the Radar Cross Section. Optically transparent metasurfaces could be integrated and exploited in windows and transparent surfaces in future Beyond-5G and 6G ecosystems.

12.
Biomater Adv ; 145: 213272, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36586204

ABSTRACT

A novel hybrid nanocomposite formed of carboxylated Nano Graphene Oxide (c-NGO), highly densely decorated by monodisperse citrate-coated Au nanoparticles (c-NGO/Au NPs), is synthesized and thoroughly characterized for photothermal applications. A systematic investigation of the role played by the synthetic parameters on the Au NPs decoration of the c-NGO platform is performed, comprehensively studying spectroscopic and morphological characteristics of the achieved nanostructures, thus elucidating their still not univocally explained synthesis mechanism. Remarkably, the Au NPs coating density of the c-NGO sheets is much higher than state-of-the-art systems with analogous composition prepared with different approaches, along with a higher NPs size dispersion. A novel theoretical approach for estimating the average number of NPs per sheet, combining DLS and TEM results, is developed. The assessment of the c-NGO/Au NPs photothermal activity is performed under continuous wave (CW) laser irradiation, at 532 nm and 800 nm, before and after functionalization with PEG-SH. c-NGO/Au NPs composite behaves as efficient photothermal agent, with a light into heat conversion ability higher than that of the single components. The c-NGO/Au NPs compatibility for photothermal therapy is assessed by in vitro cell viability tests, which show no significant effects of c-NGO/Au NPs, as neat and PEGylated, on cell metabolic activity under the investigated conditions. These results demonstrate the great potential held by the prepared hybrid nanocomposite for photothermal conversion technologies, indicating it as particularly promising platform for photothermal ablation of cancer cells.


Subject(s)
Metal Nanoparticles , Oxides , Oxides/pharmacology , Oxides/chemistry , Gold/pharmacology , Gold/chemistry , Cell Line, Tumor , Metal Nanoparticles/therapeutic use , Metal Nanoparticles/chemistry , Lasers
13.
BMJ Open ; 12(8): e063081, 2022 08 01.
Article in English | MEDLINE | ID: mdl-35914905

ABSTRACT

INTRODUCTION: Viability assessment of the graft is essential to lower the risk of liver transplantation (LT) failure and need for emergency retransplantation, however, this still relies mainly on surgeon's experience. Post-LT graft function recovery assessment is also essential to aid physicians in the management of LT recipients and guide them through challenging decision making.This study aims to trial the use of indocyanine green clearance test (IGT) in the donor as an objective tool to assess graft viability and in the recipient to assess graft function recovery after LT. METHODS AND ANALYSIS: This is an observational prospective single-centre study on consecutive liver transplant donors and recipients. PRIMARY OBJECTIVE: To determine the capability of IGT of predicting graft viability at the time of organ retrieval. Indocyanine green will be administered to the donor and the plasma disappearance rate (PDR) measured using the pulsidensitometric method. Some 162 IGT donor procedures will be required (α, 5%; ß, 20%) using an IGT-PDR cut-off value of 13% to achieve a significant discrimination between viable and non-viable grafts. SECONDARY OBJECTIVE: IGT-PDR will be measured at different time-points in the LT recipient: during the anhepatic phase, after graft reperfusion, at 24 hours, on day 3 and day 7 after LT. The slope of IGT values from the donor to the recipient will be evaluated for correlation with the development of early allograft dysfunction. ETHICS AND DISSEMINATION: This research protocol was approved by Fondazione Policlinico Universitario Agostino Gemelli IRCCS Ethics Committee (reference number: 0048466/20, study ID: 3656) and by the Italian National Transplant Center (CNT) (reference number: Prot.11/CNT2021). Liver recipients will be required to provide written informed consent. Results will be published in international peer-reviewed scientific journals and presented in congresses. TRIAL REGISTRATION NUMBER: NCT05228587.


Subject(s)
Liver Transplantation , Graft Survival , Humans , Indocyanine Green , Liver/surgery , Liver Transplantation/methods , Observational Studies as Topic , Prospective Studies , Recovery of Function , Tissue and Organ Harvesting
14.
J Pers Med ; 12(7)2022 Jul 19.
Article in English | MEDLINE | ID: mdl-35887667

ABSTRACT

Background: To investigate the effects of the COVID-19 lockdowns on the vasculopathic population. Methods: The Divisions of Vascular Surgery of the southern Italian peninsula joined this multicenter retrospective study. Each received a 13-point questionnaire investigating the hospitalization rate of vascular patients in the first 11 months of the COVID-19 pandemic and in the preceding 11 months. Results: 27 out of 29 Centers were enrolled. April-December 2020 (7092 patients) vs. 2019 (9161 patients): post-EVAR surveillance, hospitalization for Rutherford category 3 peripheral arterial disease, and asymptomatic carotid stenosis revascularization significantly decreased (1484 (16.2%) vs. 1014 (14.3%), p = 0.0009; 1401 (15.29%) vs. 959 (13.52%), p = 0.0006; and 1558 (17.01%) vs. 934 (13.17%), p < 0.0001, respectively), while admissions for revascularization or major amputations for chronic limb-threatening ischemia and urgent revascularization for symptomatic carotid stenosis significantly increased (1204 (16.98%) vs. 1245 (13.59%), p < 0.0001; 355 (5.01%) vs. 358 (3.91%), p = 0.0007; and 153 (2.16%) vs. 140 (1.53%), p = 0.0009, respectively). Conclusions: The suspension of elective procedures during the COVID-19 pandemic caused a significant reduction in post-EVAR surveillance, and in the hospitalization of asymptomatic carotid stenosis revascularization and Rutherford 3 peripheral arterial disease. Consequentially, we observed a significant increase in admissions for urgent revascularization for symptomatic carotid stenosis, as well as for revascularization or major amputations for chronic limb-threatening ischemia.

15.
Chin Clin Oncol ; 11(3): 23, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35818855

ABSTRACT

BACKGROUND AND OBJECTIVE: Tumors of the ampulla of Vater are a rare set of lesions that arise at the confluence of the common bile duct (CBD) and the pancreatic duct. They can be benign or malignant, often not easy to discriminate before treatment. Malignant tumors have low chances of survival (overall 5-year survival between 0% and 60%) and surgery is still the only curative option. Prognostic factors are being investigated to tailor therapeutic approach and improve outcomes. Due to their location in a complex anatomical region, all treatment options are challenging and associated with relevant morbidity. In this review we discuss different excisional techniques for the treatment of ampullary tumors (AT). METHODS: A review of medical databases (PubMed and Google Scholar) was conducted selecting most relevant articles in English language without a specific timeframe. After first selection, most relevant citations were identified through snowballing. KEY CONTENT AND FINDINGS: Pancreatoduodenectomy (PD) is the gold standard in malignant tumors, achieving the most radical treatment, at the price of worse perioperative morbidity/mortality and quality of life. Trans-duodenal ampullectomy (TDA) was developed before endoscopic resection (ER) and maintains a role only in selected patients. ER is now the first choice for benign lesions and expanding towards early stages malignant AT. CONCLUSIONS: Pancreatodudenectomy remains the best option for the radical excision of malignant AT, recently being offered also via minimally invasive approach. However, in early-stage malignant tumors, ER is gaining importance with foreseeable further expansion. Transduodenal ampullectomy still has a role in selected patients, such as unfit for PD when ER is not possible mainly due to anatomical abnormalities.


Subject(s)
Ampulla of Vater , Common Bile Duct Neoplasms , Ampulla of Vater/pathology , Ampulla of Vater/surgery , Common Bile Duct Neoplasms/pathology , Common Bile Duct Neoplasms/surgery , Endoscopy , Humans , Pancreaticoduodenectomy/methods , Quality of Life , Retrospective Studies , Treatment Outcome
16.
Sci Rep ; 12(1): 8703, 2022 May 24.
Article in English | MEDLINE | ID: mdl-35610345

ABSTRACT

Nitrogen substitutional doping in the π-basal plane of graphene has been used to modulate the material properties and in particular the transition from hole to electron conduction, thus enlarging the field of potential applications. Depending on the doping procedure, nitrogen moieties mainly include graphitic-N, combined with pyrrolic-N and pyridinic-N. However, pyridine and pyrrole configurations of nitrogen are predominantly introduced in monolayer graphene:N lattice as prepared by CVD. In this study, we investigate the possibility of employing pyridinic-nitrogen as a reactive site as well as activate a reactive center at the adjacent carbon atoms in the functionalized C-N bonds, for additional post reaction like oxidation. Furthermore, the photocatalytic activity of the graphene:N surface in the production of singlet oxygen (1O2) is fully exploited for the oxidation of the graphene basal plane with the formation of pyridine N-oxide and pyridone structures, both having zwitterion forms with a strong p-doping effect. A sheet resistance value as low as 100 Ω/□ is reported for a 3-layer stacked graphene:N film.

17.
Bioengineering (Basel) ; 9(4)2022 Mar 29.
Article in English | MEDLINE | ID: mdl-35447705

ABSTRACT

Periapical implantitis (IPL) is an increasingly frequent complication of dental implants. The causes of this condition are not yet entirely clear, although a bacterial component is certainly part of the etiology. In this case series study, two approaches will be described: because of persistent IPL symptoms, a patient had the implant removed and underwent histological analysis after week 6 from implantation. The histomorphometric examination revealed a 35% bone-implant contact area involving the coronal two-thirds of the implant. The apical portion of the fixture on the other hand was affected by an inflammatory process detectable on radiography as a radiolucent area. The presence of a probable root fragment, detectable as an imprecise radiopaque mass in the zone where the implant was later placed, confirms the probable bacterial etiology of this case of IPL. On the other hand, in case number 2, the presence of IPL around the fixture was solved by surgically removing the implant apical third as well as the adjacent tooth apex. It may be concluded from our histological examination that removal of the apical portion of the fixture should be considered an effective treatment for IPL since the remaining implant segment remains optimally osseointegrated and capable of continuing its function as a prosthetic abutment. Careful attention, however, is required at the implantation planning stage to identify in advance any sources of infection in the edentulous area of interest which might compromise the final outcome.

18.
Nanomaterials (Basel) ; 12(3)2022 Jan 28.
Article in English | MEDLINE | ID: mdl-35159811

ABSTRACT

From the group-III monochalcogenide (MX, M = Ga, In; X = S, Se, Te) layered semiconductors, gallium monosulfide, GaS, has emerged as a promising material for electronics, optoelectronics, and catalysis applications. In this work, GaS samples of various thicknesses in the range from 38 to 1665 nm have been obtained by mechanical exfoliation to study the interplay between structural, morphological, optical, and photoresponsivity properties as a function of thickness. This interplay has been established by analyzing the structure through Raman spectroscopy and X-ray diffraction, the morphology through scanning electron microscopy and atomic force microscopy, the density and optical properties through spectroscopic ellipsometry, and the photoresponsivity through current-voltage measurements under UV light. This work shows that photoresponsivity increases with increases in GaS thickness, resulting in a UV photoresponsivity of 1.5·10-4 AW-1 stable over several on/off cycles.

19.
Article in English | MEDLINE | ID: mdl-34997291

ABSTRACT

Spontaneous magnetic alignment is the simplest known directional response to the geomagnetic field that animals perform. Magnetic alignment is not a goal directed response and its relevance in the context of orientation and navigation has received little attention. Migratory songbirds, long-standing model organisms for studying magnetosensation, have recently been reported to align their body with the geomagnetic field. To explore whether the magnetic alignment behaviour in songbirds is involved in the underlying mechanism for compass calibration, which have been suggested to occur near to sunset, we studied juvenile Eurasian reed warblers (Acrocephalus scirpaceus) captured at stopover during their first autumn migration. We kept one group of birds in local daylight conditions and an experimental group under a 2 h delayed sunset. We used an ad hoc machine learning algorithm to track the birds' body alignment over a 2-week period. Our results show that magnetic body alignment occurs prior to sunset, but shifts to a more northeast-southwest alignment afterwards. Our findings support the hypothesis that body alignment could be associated with how directional celestial and magnetic cues are integrated in the compass of migratory birds.


Subject(s)
Songbirds , Animal Migration , Animals , Magnetic Phenomena , Magnetics , Orientation/physiology , Songbirds/physiology
20.
Hist Psychol ; 25(2): 170-189, 2022 05.
Article in English | MEDLINE | ID: mdl-34516192

ABSTRACT

The present article assesses the hidden importance of Georges Politzer's (1903-1942) work in the development of French philosophy and psychology. After sketching his biography and isolating the most important concepts developed in his book Critique of the Foundations of Psychology (1928), this article proceeds by dividing his reception into four distinct moments, the features of which derive from the interconnected mutations of the scientific field in its relation with the transformation of the political field. In the first moment, the publication of the Critique, Politzer's most important work, played an essential role in introducing psychoanalysis into philosophy, psychology, and psychiatry, and in sketching the path of a possible encounter between psychoanalysis and Marxism. In the second moment, during the 1940s and the 1950s, following Politzer's Marxist auto-critique, French communists widely rejected psychoanalysis as a dangerous ideology. In the third moment, during the 1960s in a context marked by structuralism, both the psychoanalysts and the Marxists addressed to Politzer's humanism a new, theoretical, critique. Finally, at the end of the 1960s and even more after May 1968, Politzer's works were republished and reevaluated, and new transformations taking place in the intellectual and political field during the 1970s contributed to a better understanding of Politzer's essential role in French philosophy, psychology, and psychoanalysis. (PsycInfo Database Record (c) 2022 APA, all rights reserved).


Subject(s)
Psychiatry , Psychoanalysis , Communism , France , History, 20th Century , Philosophy , Psychology
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