On the Electrochemical Growth of a Crystalline p-n Junction From Aqueous Solutions.

Our society largely relies on inorganic semiconductor devices which are, so far, fabricated using expensive and complex processes requiring ultra-high vacuum equipment. Here we report on the possibility of growing a p-n junction taking advantage of electrochemical processes based on the use of aqueous solutions. The growth of the junction has been carried out using the Electrochemical Atomic Layer Deposition (E-ALD) technique, which allowed to sequentially deposit two different semiconductors, CdS and Cu2S, on an Ag(111) substrate, in a single procedure. The growth process was monitored in situ by Surface X-Ray Diffraction (SXRD) and resulted in the fabrication of a thin double-layer structure with a high degree of crystallographic order and a well-defined interface. The high-performance electrical characteristics of the device were analysed ex-situ and show the characteristic feature of a diode.

Anatomical Study and Clinical Application of Ulnar Artery Proximal Perforator Flaps.

BACKGROUND: The purpose of this study is to document the vascular anatomy of the free ulnar artery proximal perforator flap and to highlight the possibility of harvesting it based on the perforators originating from the posterior ulnar recurrent artery (PURA), to spare both the main axis of vascular supply to the hand. In addition, we present a case series of five patients treated for soft tissue defects of the hand with free ulnar artery proximal perforator flaps. METHODS: Ten specimens of anterior forearm were dissected in this study to register number and characteristics of ulnar perforators. The dissection was focused on the perforators originating from the larger branch of the ulnar artery, the PURA, at the proximal third of anteromedial forearm. The anatomical dissections were evaluated in relationship with clinical dissections performed during flap harvesting in five patients. RESULTS: In three of the specimens dissected, the proximal perforator originated from the PURA, and in the other seven specimens, it originated directly from the ulnar artery. Five cases of reconstruction of the hand were performed with success using the free ulnar artery proximal perforator flap, and in two cases, the perforator from the PURA was found and it was possible to raise the flap based on this branch of the ulnar artery. CONCLUSION: The free ulnar artery proximal perforator flap can be harvested in two different manners for the same skin island of the forearm. When possible, harvesting it form the PURA allows lengthening of the pedicle. In our experience, this flap presents many advantages such as thinness and hairlessness; it allows preservation of the ulnar neurovascular bundle with an acceptable donor site morbidity. LEVEL OF EVIDENCE: IV.

Sensitive peripheral nerve repair during COVID-19 emergency: does the outpatient surgical setting work as well as the operating theater?

Background: Nerve injuries are a common occurrence among hand injuries, which at the time of the COVID-19 emergency, did not appear to have reduced their incidence. The treatment of these injuries is urgent, but the pandemic has led to a reduction in the availability of resources and a consequent reorganization of activities. Principles about Wide-Awake Local Anesthesia No Tourniquet (WALANT) in hand surgery expressed by LaLonde helped hand surgeons to adapt to this new condition by demonstrating a possible outpatient pathway for the treatment of hand traumatic conditions. In the present study, we bring our experience in nerve repair at time of COVID-19 emergency. Methods: We retrospectively enrolled in this study all patients surgically treated for a peripheral nerve injury (PNI) during the COVID-19 emergency period from March 2020 to March 2022. Demographical, anamnestic, surgical, and postoperative data were recorded and analyzed. Persisting Tinel was set as the primary outcome, while hypoesthesia and other complications as secondary outcomes. Results: Thirty-six patients have been enrolled. Despite some difference in group homogeneity in term of hypertension and multi-digital involvement, we registered no difference in term of outcomes (P > 0.05) between patient operated in surgical theater and in outpatient clinic and between the various techniques of nerve repair employed (P > 0.05). Conclusions: Nerve repair on an outpatient facility is technically feasible and was found in this study to be safe and effective. Compared to hospitalization, the outpatient setting has a more "agile" organization and lower costs, making it preferable in selected cases.Level of evidence: Level IV, Therapeutic.

Interplay between abiotic and microbial biofilm-mediated processes for travertine formation: Insights from a thermal spring (Piscine Carletti, Viterbo, Italy).

Active hydrothermal travertine systems are ideal environments to investigate how abiotic and biotic processes affect mineralization mechanisms and mineral fabric formation. In this study, a biogeochemical characterization of waters, dissolved gases, and microbial mats was performed together with a mineralogical investigation on travertine encrustations occurring at the outflow channel of a thermal spring. The comprehensive model, compiled by means of TOUGHREACT computational tool from measured parameters, revealed that mineral phases were differently influenced by either abiotic conditions or microbially driven processes. Microbial mats are shaped by light availability and temperature gradient of waters flowing along the channel. Mineralogical features were homogeneous throughout the system, with euhedral calcite crystals, related to inorganic precipitation induced by CO2 degassing, and calcite shrubs associated with organomineralization processes, thus indicating an indirect microbial participation to the mineral deposition (microbially influenced calcite). The microbial activity played a role in driving calcite redissolution processes, resulting in circular pits on calcite crystal surfaces possibly related to the metabolic activity of sulfur-oxidizing bacteria found at a high relative abundance within the biofilm community. Sulfur oxidation might also explain the occurrence of gypsum crystals embedded in microbial mats, since gypsum precipitation could be induced by a local increase in sulfate concentration mediated by S-oxidizing bacteria, regardless of the overall undersaturated environmental conditions. Moreover, the absence of gypsum dissolution suggested the capability of microbial biofilm in modulating the mobility of chemical species by providing a protective envelope on gypsum crystals.

Social Perception of Reconstruction following Orbital Exenteration.

BACKGROUND: Orbital exenteration, the removal of the entire globe, eyelids, and orbital content, is indicated in extensive neoplastic disease involving the orbital region. Although a functional reconstruction of orbital exenteration defects is mandatory, aesthetic concerns need to be considered. Facial disfigurement following reconstructive surgery often leads to great discomfort and social retirement, which can limit social interaction. The aim of this study was to explore how the society perceives the aspect of patients who underwent orbital exenteration and subsequent reconstruction, comparing two different types of reconstruction: standard anterolateral thigh (ALT) or "sandwich" fascial ALT (SALT) free flap. METHODS: An online survey was created based on four questions regarding the perception of reconstruction (discomfort at looking at that patient, perception of unhealthiness, hypothesis of social life impairment, etc); five possible answers were provided, ranging from "completely" to "not at all." The survey was administered to the general population and to medical students. RESULTS: In total, 255 people participated to the survey (130 medical students and 125 people of the general population); a total of 245 surveys were considered eligible (10 were incomplete and then discharged). Statistical significance was found (P < 0.001) regarding the better overall appearance of the SALT group over the ALT one. CONCLUSIONS: After analysis, the surgical outcome after SALT reconstruction has been found to be less disruptive in both groups, due to a reduced scar burden and a more pleasant orbital pocket. Our results encourage more research in the field of postexenteration reconstruction to achieve more aesthetic and social acceptability.