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1.
Chem Sci ; 12(15): 5621-5630, 2021 Mar 17.
Article in English | MEDLINE | ID: mdl-34168797

ABSTRACT

We explore how to encode more than a qubit in vanadyl porphyrin molecules hosting a S = 1/2 electronic spin coupled to a I = 7/2 nuclear spin. The spin Hamiltonian and its parameters, as well as the spin dynamics, have been determined via a combination of electron paramagnetic resonance, heat capacity, magnetization and on-chip magnetic spectroscopy experiments performed on single crystals. We find low temperature spin coherence times of micro-seconds and spin relaxation times longer than a second. For sufficiently strong magnetic fields (B > 0.1 T, corresponding to resonance frequencies of 9-10 GHz) these properties make vanadyl porphyrin molecules suitable qubit realizations. The presence of multiple equispaced nuclear spin levels then merely provides 8 alternatives to define the '1' and '0' basis states. For lower magnetic fields (B < 0.1 T), and lower frequencies (<2 GHz), we find spectroscopic signatures of a sizeable electronuclear entanglement. This effect generates a larger set of allowed transitions between different electronuclear spin states and removes their degeneracies. Under these conditions, we show that each molecule fulfills the conditions to act as a universal 4-qubit processor or, equivalently, as a d = 16 qudit. These findings widen the catalogue of chemically designed systems able to implement non-trivial quantum functionalities, such as quantum simulations and, especially, quantum error correction at the molecular level.

2.
Article in English | MEDLINE | ID: mdl-33572503

ABSTRACT

Dementia produces a loss of independence to carry out the activities of daily life. The great demand for care that these people need usually falls on the family through informal care. This study aims to analyse the burden showed by the informal caregiver of a person with dementia. In addition, we analyse whether this burden present in informal caregivers could be related to abusive behaviour. We also study the relationship between the stage of the disease, the appearance of behavioural disorders and the level of burden in the caregiver using the Scales of Zarit, CASE and FAST. The data showed that 45.50 per cent of caregivers have light burden or burden. After the research, it was identified that the presence of behavioural disorders in patients with dementia showed a correlation with the increase in both the main caregiver burden and abuse. An increase in the level of burden is followed by an increase in the level of abuse (r = 0.844; p = 0.000). Furthermore, we analysed several conditions that could have a correlation with this burden and abuse. It was found that burden in the caregiver could be linked with the presence of behavioural disorders, like aggression (r = 0.577; p = 0.008) and irritability (r = 0.600; p = 0.005) at the moderate stage of the disease. On the other hand, there is a positive correlation between the probability that people with dementia suffer abuse in the moderate stage of the disease and the presence of aggression (r = 0.732; p = 0.000), lack of inhibition (r = 0.571; p = 0.009) and irritability (r = 0.827; p = 0.000). Taking this data into account, burden and abuse seem to be linked to the presence of behavioural disorders in patients with dementia in the moderate stage.


Subject(s)
Caregivers , Dementia , Aggression , Caregiver Burden , Cost of Illness , Dementia/epidemiology , Humans
3.
ACS Nano ; 14(7): 8707-8715, 2020 Jul 28.
Article in English | MEDLINE | ID: mdl-32441922

ABSTRACT

We combine top-down and bottom-up nanolithography to optimize the coupling of small molecular spin ensembles to 1.4 GHz on-chip superconducting resonators. Nanoscopic constrictions, fabricated with a focused ion beam at the central transmission line, locally concentrate the microwave magnetic field. Drops of free-radical molecules have been deposited from solution onto the circuits. For the smallest ones, the molecules were delivered at the relevant circuit areas by means of an atomic force microscope. The number of spins Neff effectively coupled to each device was accurately determined combining Scanning Electron and Atomic Force Microscopies. The collective spin-photon coupling constant has been determined for samples with Neff ranging between 2 × 106 and 1012 spins, and for temperatures down to 44 mK. The results show the well-known collective enhancement of the coupling proportional to the square root of Neff. The average coupling of individual spins is enhanced by more than 4 orders of magnitude (from 4 mHz up to above 180 Hz), when the transmission line width is reduced from 400 µm down to 42 nm, and reaches maximum values near 1 kHz for molecules located on the smallest nanoconstrictions.

4.
Am J Dermatopathol ; 41(2): 85-117, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30688725

ABSTRACT

After a review of the physiology in the formation and degradation of cutaneous elastic tissue, we describe the clinicopathologic disorders characterized by increased and decreased cutaneous elastic tissue. Cutaneous disorders characterized by increased and/or abnormal elastic tissue in the dermis include elastoma, also named nevus elasticus, dermatosis lenticularis disseminata, pseudoxanthoma elasticum, late-onset focal dermal elastosis, linear focal elastosis, elastoderma, elastofibroma dorsi, and elastosis perforans serpiginosa. In some of these conditions, the specific histopathologic diagnosis may be rendered with hematoxylin-eosin stain, whereas in other ones special elastic tissue stains are necessary to demonstrate the anomalies. Cutaneous disorders characterized by decreased dermal elastic tissue include nevus anelasticus, papular elastorrhexis, perifollicular elastolysis, anetoderma cutis laxa, postinflammatory elastolysis and cutis laxa, white fibrous papulosis of the neck, pseudoxanthoma elasticum-like papillary dermal elastolysis, and mid dermal elastolysis. In most of these conditions, the histopathologic anomalies are only seen with elastic tissue stains, and cutaneous biopsies of these processes stained with hematoxylin-eosin show appearance of normal skin. The diagnosis of some of these disorders characterized by increased or decreased elastic dermal tissue should be followed by general exploration of the patient to rule out associated severe systemic anomalies, and in some cases, a genetic counseling should be offered to the family.


Subject(s)
Elastic Tissue/pathology , Skin Diseases/pathology , Connective Tissue Diseases/pathology , Humans
5.
Am J Dermatopathol ; 39(6): 471-475, 2017 Jun.
Article in English | MEDLINE | ID: mdl-27906695

ABSTRACT

Fixed drug eruption (FDE) consists of recurrent dusky-red to brownish macules or patches at the same sites after the readministration of the causative drug. It usually presents as a solitary lesion, but generalized eruptions have been described. The most frequently implied drugs are antibiotics, anticonvulsants, and analgesics. Only 2 cases due to metformin have been reported. Histopathologic features of FDE include vacuolar degeneration of the basal layer, necrotic keratinocytes, and superficial and deep perivascular lymphocytic infiltrate. Cutaneous hemophagocytosis in the context of a FDE has not been previously reported. We describe the case of an 86-year-old man who developed a pruritic generalized macular eruption of reddish to violaceous patches. Skin biopsy was performed and the dermal infiltrate was immunohistochemically studied. Histopathology showed interface dermatitis with vacuolar degeneration of the basal layer, necrotic keratinocytes, and superficial and deep perivascular lymphohistiocytic infiltrate. In deep dermis, histiocytes with engulfed cells inside their cytoplasm were seen. Lymphoid enhancer binding factor 1 immunostain demonstrated that most of these cells were lymphocytes. We present the first case with cutaneous hemophagocytosis in the context of a metformin-induced generalized FDE. In this particular case, hemophagocytosis was just a histopathologic finding with no systemic consequences for the patient.


Subject(s)
Diabetes Mellitus, Type 2/drug therapy , Drug Eruptions/etiology , Hypoglycemic Agents/adverse effects , Lymphohistiocytosis, Hemophagocytic/chemically induced , Metformin/adverse effects , Skin/drug effects , Aged, 80 and over , Biopsy , Drug Eruptions/pathology , Drug Eruptions/therapy , Drug Substitution , Histiocytes/chemistry , Histiocytes/drug effects , Histiocytes/pathology , Humans , Hypoglycemic Agents/administration & dosage , Immunohistochemistry , Lymphocytes/chemistry , Lymphocytes/drug effects , Lymphocytes/pathology , Lymphohistiocytosis, Hemophagocytic/pathology , Lymphohistiocytosis, Hemophagocytic/therapy , Lymphoid Enhancer-Binding Factor 1/analysis , Male , Metformin/administration & dosage , Sitagliptin Phosphate/administration & dosage , Skin/chemistry , Skin/pathology , Treatment Outcome
6.
J Cutan Pathol ; 44(3): 283-288, 2017 Mar.
Article in English | MEDLINE | ID: mdl-27778364

ABSTRACT

Liposarcoma, usually arises in deep soft tissues and pleomorphic liposarcoma (PL), is the rarest histopathologic variant. However, 15 cases of entirely dermal PL have been reported. We describe a case of a 79-year-old man who developed a rapidly growing nodule on his thorax. Excisional biopsy was performed and immunohistochemical studies were carried. The lesion was a well-circumscribed dermal nodule composed of multivacuolated pleomorphic lipoblasts and atypical mitotic figures. Neoplastic cells expressed CD10 and resulted negative S100 protein, Melan-A, MITF-1, AE1/AE3, CD4, CD68 (PGM1), retinoblastoma gene family protein, pericentrine and lysozyme. Adipophilin stain showed the lipid contents in the cytoplasm of the neoplastic cells. MDM2 and CDK4 resulted both negative. A diagnosis of primary dermal PL was made. This case shows the utility of adipophilin immunostaining to prove the lipid contents in neoplastic cells, which has the advantage of using formalin-fixed paraffin-embedded tissue and making needless frozen sections and ultrastructural studies to show these findings. Negative MDM2/CDK4 staining in our case argues against the possibility of dedifferentiated liposarcoma and further supports the diagnosis of true PL.


Subject(s)
Biomarkers, Tumor/analysis , Liposarcoma/diagnosis , Perilipin-2/biosynthesis , Skin Neoplasms/diagnosis , Aged , Cyclin-Dependent Kinase 4/analysis , Cyclin-Dependent Kinase 4/biosynthesis , Humans , Immunohistochemistry , Male , Perilipin-2/analysis , Proto-Oncogene Proteins c-mdm2/analysis , Proto-Oncogene Proteins c-mdm2/biosynthesis
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