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Patients with hypertrophic lichen planus (HLP) and squamous cell carcinoma (SCC) diagnoses present clinicians with diagnostic and disease management challenges.To better define the clinical and treatment outcomes of patients with concomitant diagnoses of HLP and SCC.A retrospective review was performed from January 1, 2008, to July 31, 2015, at Mayo Clinic. Patients with a histologic diagnosis of HLP and SCC were included. Patient demographics, associated comorbidities, histopathologic characteristics, treatment, and outcomes were evaluated.Thirty-three patients were identified; 79% were female, and mostly the lower extremities were involved. Most of the SCCs were well-differentiated and in situ with the majority treated with destruction or excision. There were no cases of local recurrence, metastasis, or disease-specific death during the follow-up period (mean 55.8 months).Patients with diagnoses of both HLP and SCC appear to be a distinct population that is predominantly female with lesion predilection for the lower extremities. However, regardless of treatment modality or tumor size, there were no adverse outcomes. An initial trial of more conservative treatment measures with close follow-up may be reasonable with biopsy of lesions unresponsive to conventional treatment.

MgO@TiO2@g-C3N4 heteronanostructure was synthesized using a simple ultrasonication technique and assessed potentially to remove Cd (II) from aqueous environments. X-ray diffraction analysis confirms composite formation with mean crystallite size in the range of 4-17 nm while transmission electron microscopy analysis reveals nanosheet-like nanoparticles with the homogeneous elemental distribution. N2 adsorption-desorption measurements indicate the formation of a mesoporous structure with a BET surface area of about 107 m2/g. Fourier-transformed infrared elucidates the presence of O–H, amino groups, triazine, Mg–O, and Ti–O vibrations modes. At the same time, X-ray photoelectron spectroscopy analysis manifests the presence of Mg, O, N, Ti, and C elements. For aqueous Cd (II) ions, the MgO@TiO2@g-C3N4 nanostructure displays a superior adsorption efficiency, reaching 99.94% Cd (II) elimination with an optimum adsorption capacity of 515.86 mg/g in a short duration of 16 min. This study demonstrates the capability of using the MgO@TiO2@g-C3N4 nanostructure as an efficient and reusable adsorbent for the uptake of Cd (II) ions in wastewater treatment and potentially for the removal of other heavy metal ions.

A variety of OH containing molecules in their different modes of adsorption onto the rutile TiO

The potential of CeO

A variety of OH containing molecules in their different modes of adsorption onto the rutile TiO2(110) are studied by means of density functional theory. A special focus is given to ethanol, ethylene glycol and glycerol. The different species were analyzed with respect to the adsorption energy, work function, and atomic Bader charges. Our results show that dissociated adsorption is favored in all cases. Within these modes, the strongest binding is observed in the case of bidentate fully dissociated adsorption, followed by bidentate partially dissociated then the monodentate dissociated modes. The dependence is also noted upon charge transfer analysis. Species adsorbing with two dissociated OH groups show a negative charge which is roughly twice as large compared to those exhibiting only one dissociated group. In the case of molecular adsorption, we find a small positive charge on the adsorbate. The change in work functions obtained is found to be negative in all studied cases. We observe a trend of the work function change being more negative for glycerol (3 OH groups) followed by ethylene glycol (2 OH groups) and the remaining alcohols (1 OH group), thus indicating that the number of OH groups present is an important factor in regards to work function changes. For the complete series of adsorbates studied (methanol, ethanol, isopropanol, ethylene glycol, glycerol, hydrogen peroxide and formic acid) there is a linear relationship between the change in the work function and the adsorption energy for the molecular adsorption mode. The relationship is less pronounced for the dissociated adsorption mode for the same series.

Metal/semiconductor interactions affect electron transfer rates and this is central to photocatalytic hydrogen ion reduction. While this interaction has been studied in great detail on metal oxide semiconductors, not much is known of Au particles on top of polymeric semiconductors. The effects of gold nanoparticle size and dispersion on top of g-C3N4 were studied by core and valence level spectroscopy and transmission electron microscopy in addition to catalytic tests. The as-prepared, non-calcined catalysts displayed Au particles with uniform dimension (mean particle size = 1.8 nm) and multiple electronic states: XPS Au 4f7/2 lines at 84.9 and 87.1 eV (each with a spin-orbit splitting of 3.6-3.7 eV). These particles, which did not show localized surface plasmon resonance (LSPR), before the reaction, doubled in size after the reaction giving a pronounced LSPR at about 550 nm. The effect of the heating environment on these particles (in air or in H2) was further investigated. While heating in H2 gave Au nanoparticles of different shapes, heating under O2 gave exclusively spherical particles. Similar activity towards photocatalytic hydrogen ion reduction under UV excitation was seen in both cases, however. XPS Au 4f analyses indicated that an increase in deposition time, during catalyst preparation, resulted in an increase in the initial fraction of oxidized gold particles, which were easily reduced under hydrogen. The valence band region for Au/gC3N4 was further studied in an effort to compare it to what is already known for Au/metal oxide semiconductors. A shift of over 2 eV for the Au 5d doublets was noticed between reduced and oxidized gold particles with mean particle sizes between 2 and 6 nm, which is consistent with the final state effect. A narrow range of gold loading for optimal catalytic performance was seen, where it seems that a density of one Au particle per 10 × 10 nm2 is the most suitable. Particle size and shape had a minor effect on performance, which may indicate the absence of a plasmonic effect on the reaction rate.

A triple junction (3J) solar cell having 33% efficiency at one Sun condition is integrated with an electrolyzer containing Pt wire electrodes to study the effect of pH, temperature and low flux solar light on H2 production from water. Results indicate that electrolyte conduction affects the rate of reaction mostly due to the large voltage at maximum power (Vmpp) of the PV-cell. Measurements are performed both indoors, under 100–500 mWcm−2 insolation, and outdoors. Electrochemical impedance measurements indicate that the exchange current, ji, depends largely on the electrolyte resistance, r (ji = (Vapp-Veq)/r); where Vapp is applied voltage provided from the cell and Veq is the equilibrium potential for water electrolysis (1.23 V). The small increase in the hydrogen production rate with temperature (Ea = 4.4 kJ mol−1) is largely because of the high Vapp, where above 1.6 V the IV curve enters into the Tafel slope region. The maximum solar-to-hydrogen conversion efficiency (STH) outdoor is found to be about 16% under acidic conditions. The high Vmpp (2.5 V) of the PV cell compared to Vopp (1.7 V) makes the current at maximum power (Impp) the limiting factor.

Background, Diagnosis of leprosy mainly relies on clinical examination due to the inconsistent sensitivity and poor reproducibility of the current laboratory tests. Utilisation of alternative methods to the standard Ziehl Neelsen (ZN), Fite-Faraco (FF) and Haematoxylin and Eosin (H&E) staining procedures may eventually improve leprosy diagnosis., Methodology/Principal findings, In this comparative study, the performance of the fluorescent Auramine O (AO) staining and polymerase chain reaction (PCR) was assessed with different skin samples using a combination of ZN, FF and H&E staining as the gold standard. AO, ZN, FF, H&E and PCR tests were performed on slit skin smears (SSS) and/or punch biopsies collected from 141 clinically confirmed leprosy cases and 28 non-leprosy skin samples. DNA was extracted from punch biopsies using two different methods with or without mechanical lysis., Sensitivities were 87.6%, 59.3% and 77% for H&E, ZN and FF, respectively, whereas it reached 65.5% and 77.9% for AO in SSS and tissue sections and 91.1% for PCR in tissue samples. Morover, samples with low bacillary index, sensitivity of AO staining (61.8%) was similar to FF (60%, p>0.05) and lower than PCR (86.6%, p, Conclusions/Significance, Our results showed that for diagnostic purposes, analysis of skin section is more sensitive than SSS, especially for samples with low bacillary load. AO staining on SSS and tissue sections was not significantly better than other routine diagnostic tests but considerably more user friendly. The sensitivity of PCR was higher than current standard methods and increased when combined with more efficient DNA extraction using mechanical and chemical lysis. Therefore, we recommend AO staining for the diagnosis of leprosy in lower health facilities such as health centres and district hospitals and PCR diagnosis at referral level and research centres.

Photo-thermal catalytic reactions of ethanol over Ag/TiO2 were conducted in order to probe into the role of plasmonic resonance response in the reaction kinetics. In the 300-500 K temperature domain the increase in reaction rate is found to be mainly due to changes in the activation energy while above this temperature range the increase was due to the pre-exponential factor. These results might be linked to the role of plasmonic Ag particles in polarising the reaction intermediates and therefore increasing the reaction products at temperatures up to about 500 K.

Background Some examples of Bowen disease lack the characteristic broad parakeratosis making their histopathologic diagnosis particularly difficult in small and incomplete biopsies. Materials and Methods The archives of our dermatopathology laboratory were searched for cases of Bowen disease with >75% orthokeratosis (orthokeratotic Bowen disease) and classic Bowen disease (>25% parakeratosis). Selected specimens were evaluated histopathologically, using immunohistochemical stains (CK10, CK7, Bcl-2, p16 and Ki-67) and by DNA amplification/sequencing for human papilloma virus (HPV) subtypes. Results Among 102 consecutive samples 14 cases of orthokeratotic Bowen disease were identified. In comparison with 24 examples of classic Bowen disease, the orthokeratotic examples occurred more frequently in female and younger patients (p = 0.04 and 0.008, respectively) but shared most of the histopathologic features of classic Bowen disease except a preserved granular layer and relative absence of the eyeliner sign (p

The S100A6 protein is expressed in a variety of tissues and distinct staining patterns in S100A6 immunohistochemistry may be useful in the differential diagnosis of difficult lesions. We evaluated the staining pattern of the S100A6 antibody in 22 cases each of pilar leiomyoma (LM), angioleiomyoma (ALM), and cutaneous leiomyosarcoma (LMS). S100A6 labeled both the nucleus and cytoplasm of myocytes in positive cases. About 64% of LM and 86% ALM had positive staining to the S100A6 antibody but predominantly in a weak staining pattern. In contrast, 95% of the LMS exhibited moderate to strong staining with the S100A6 antibody. The difference in the frequency of positive cases was statistically significant in the LM vs LMS comparison (p = 0.025), but we found intensity of staining to be of greatest practical utility. Analysis between the groups taking in to consideration differences in intensity of staining using the nonparametric rank sum (Mann-Whitney U test) demonstrated that there was a statistically significant difference between LM and LMS and between ALM and LMS. Weak or absent S100A6 staining supports a diagnosis of LM, whereas strong positive staining supports a diagnosis of LMS.

Background Leprosy reactions are a significant cause of morbidity in leprosy population. Erythema nodosum leprosum (ENL) is an immunological complication affecting approximately 50% of patients with lepromatous leprosy (LL) and 10% of borderline lepromatous (BL) leprosy. ENL is associated with clinical features such as skin lesions, neuritis, arthritis, dactylitis, eye inflammation, osteitis, orchitis, lymphadenitis and nephritis. ENL is treated mainly with corticosteroids and corticosteroids are often required for extended periods of time which may lead to serious adverse effects. High mortality rate and increased morbidity associated with corticosteroid treatment of ENL has been reported. For improved and evidence-based treatment of ENL, documenting the systems affected by ENL is important. We report here the clinical features of ENL in a cohort of patients with acute ENL who were recruited for a clinico-pathological study before and after prednisolone treatment. Materials and methods A case–control study was performed at ALERT hospital, Ethiopia. Forty-six LL patients with ENL and 31 non-reactional LL matched controls were enrolled to the study and followed for 28 weeks. Clinical features were systematically documented at three visits (before, during and after predinsolone treatment of ENL cases) using a specifically designed form. Skin biopsy samples were obtained from each patient before and after treatment and used for histopathological investigations to supplement the clinical data. Results Pain was the most common symptom reported (98%) by patients with ENL. Eighty percent of them had reported skin pain and more than 70% had nerve and joint pain at enrolment. About 40% of the patients developed chronic ENL. Most individuals 95.7% had nodular skin lesions. Over half of patients with ENL had old nerve function impairment (NFI) while 13% had new NFI at enrolment. Facial and limb oedema were present in 60% patients. Regarding pathological findings before treatment, dermal neutrophilic infiltration was noted in 58.8% of patients with ENL compared to 14.3% in LL controls. Only 14.7% patients with ENL had evidence of vasculitis at enrolment. Conclusion In our study, painful nodular skin lesions were present in all ENL patients. Only 58% patients had dermal polymorphonuclear cell infiltration showing that not all clinically confirmed ENL cases have neutrophilic infiltration in lesions. Very few patients had histological evidence of vasculitis. Many patients developed chronic ENL and these patients require inpatient corticosteroid treatment for extended periods which challenges the health service facility in resource poor settings, as well as the patient’s quality of life., Author summary Leprosy reactions (Type 1 and 2) are important causes of nerve damage and illness. Erythema Nodosum Leprosum (ENL) also called type 2 reactions is a severe multisystem immune-mediated complication of borderline and lepromatous leprosy. ENL causes high morbidity and mortality and usually requires urgent medical attention. ENL can occur before, during, or after completion of MDT. The diagnosis and treatment of ENL is largely based on clinical symptoms. However, the clinical symptoms are heterogeneous and may vary from patient to patient. Although thalidomide is an effective drug for ENL treatment, it is not available in many leprosy endemic countries including Ethiopia. In spite of its adverse effects, in many endemic countries corticosteroid is the only available drug for ENL treatment, usually being used for prolonged periods. Therefore, alternative and effective drugs are required to reduce the burden of ENL. To establish which drugs will be effective in the treatment of ENL it is necessary to have a clear picture of the clinical and histological features of the disease. We systematically documented these features of ENL and compared them with matched non-reactional LL controls. Thus, the findings will help to develop better ENL diagnosis and treatment options.

Objective 1. To assess the knowledge, perception, and practices of mothers/ caregivers on vaccine preventable diseases in children aged 12-23 months in Kaduna State, Nigeria 2. To determine the immunization coverages in Kaduna State, Nigeria 3. To determine the sources of information on routine immunization among mothers/caregivers of children aged 12-23months in the study area Introduction Immunization is one of the safest and most effective interventions to prevent disease and early child death 1 . Although, about three quarters of the world’s child population is reached with the required vaccines, only half of the children in Sub-Saharan Africa get access to basic immunization 2 . A substantial number of children worldwide do not complete immunization schedules because neither health services nor conventional communication mechanisms regularly reach their communities 3 . Separate studies in Australia and Papua New Guinea have shown that knowledge gaps underlie low compliance with vaccination schedules 3, 4 . Mothers are less likely to complete immunization schedules if they are poorly Informed about the need for immunization, logistics (which includes time, date, and place of vaccination), and the appropriate series of vaccines to be followed 5, 6 . Although knowledge in itself is insufficient to create demand, poor knowledge about the need for vaccination and when the next vaccination is due is a good indicator of poor compliance 7 . Up-to-date, complete, and scientifically valid information about vaccines can help parents to make informed decisions 8 . Immunity gap created by this low immunization coverage in Northern Nigeria favors the emergence and transmission of some vaccine preventable diseases (VPDs) especially measles and polio 9 . Methods A cross-sectional descriptive study was conducted using multistage sampling technique; 379 mothers/caregivers with children aged 12-23 months were recruited. Data collection was done using semi structured interviewer-administered questionnaire and analyzed using Epi info TM version 7. Descriptive statistics using absolute numbers and proportions and Odds ratio/Chi2 were determined between variables and p ≤ 0.05 was considered statistically significant. Multivariate analysis was conducted using logistic regression. Results Mean age of respondents was 28.6 (SD= ± 6.6), 245(64.7%) practiced Islam, 128(33.8%) completed Secondary school, 246(64.9%) unemployed, 361(92.3%) were married and 186(49.1%) were from rural settlements. Among the children whose mothers/ caregivers were interviewed, 163(43.01%) were between aged 16-19 months old while most 238(62.80%) fell within the birth order of 2nd -5 th child. Only 59 (15.6%) of these children were found to be fully immunized, evidenced by vaccination card history. Majority of respondents 244(64.4%) had unsatisfactory knowledge while 197(55.4%) and 204(54.0%) exhibited poor perception and bad practices respectively, regarding routine immunization. Commonest source of information was radio 69(61.61%). Educational status [OR=1.9 (95%CI:1.1-3.3)] and good perception [OR=2.6 (95%CI:1.5-4.5)] of mothers were found to be associated with getting information on routine immunization within 12months prior to this study while Polygamous family setting [OR=0.6(95%CI:0.2-0.6)], unsatisfactory knowledge [OR=0.3(95%CI:0.2-0.7)] and bad practices [OR=0.5(95%CI:0.3-0.9)] of mothers were independently associated with lack of information on routine immunization. Conclusions There is low immunization coverage in this community. Mother’s educational status, family setting, knowledge, perception and practices about immunization are important factors that influence access to information on routine immunization.

Background Nevus sebaceus is commonly associated with the development of secondary neoplasms. Data on the frequency of malignant tumors vary considerably in published reports. Objective We sought to analyze the distribution of secondary neoplasm in nevus sebaceus. Methods A retrospective analysis of all cases of nevus sebaceus diagnosed at the Ackerman Academy of Dermatopathology from 1999 to 2012 was conducted. Results A total of 706 patients (707 specimens) were included in the study. Trichoblastoma was the most frequent benign tumor (n = 52, 7.4%) followed by syringocystadenoma papilliferum (n = 33, 5.2%). Malignant tumors were present in 2.5% of the specimens with basal cell carcinoma being the most common (n = 8, 1.1%) followed by squamous cell carcinoma (n = 4, 0.57%). The incidence of secondary neoplasms was statistically related to age and anatomic site ( P Limitation Some of our cases were referred for second opinion and there may be a bias in our data toward unusual secondary neoplasms. Conclusion Our study confirms that most of the secondary neoplasms arising in association with nevus sebaceus are benign. As no malignant tumors were seen in children, we believe it is reasonable to delay surgical management until adolescence.

Melanoma can present with protean combinations and permutations of histologic features mimicking a plethora of nonmelanocytic benign and malignant proliferations. Anecdotal cases of melanoma closely simulating fibrohistiocytic proliferations have been reported. At times, the reliable differentiation between melanoma and histiocytic proliferations could be vexing histopathologically. We report an unusual presentation of melanoma in an 87-year-old man strikingly resembling xanthogranuloma both clinically and histopathologically. Histologic sections revealed a diffuse proliferation of pleomorphic cells some with foamy cytoplasm and occasional Touton-like giant cells in the dermis accompanied by inflammatory cells. Rare single-cell pagetoid scatter was evident within the epidermis. The infiltrate had patchy staining on CD163, interpreted as part of the inflammatory component but the atypical cells stained heavily with Melan A and tyrosinase confirming the diagnosis of malignant melanoma. Our case demonstrates yet another face of malignant melanoma and the critical but judicious use of immunohistochemistry in reliably distinguishing between melanoma and histiocytic tumors.

Background The mitotic index is important in the assessment of tumors such as leiomyoma (LM) and leiomyosarcoma (LMS), which may exhibit a range of cytological atypia. The mitotic marker phosphohistone-H3 (PHH3) was shown to improve interobserver and intraobserver variability in many tumors. Materials and methods We evaluated the mitotic index in 20 pilar LM and cutaneous LMS using PHH3 and hematoxylin and eosin (H&E)-stained sections. Ki-67 staining characteristics of the tumors were also assessed. Results Mitotic figures were more easily identified within PHH3 sections. The mitotic index per 10 high power fields (HPF) on the PHH3 stain was slightly higher than H&E both in the LM (mean 0.1, range 0–1 vs. mean 0) and LMS groups (mean 8.6 vs. 8.0 with range of 1–24 for both stains). The difference in mitotic index between the two stains was not statistically significant in either group (p = 0.7). The Ki-67 proliferative index showed a statistically significant correlation with a diagnosis of LMS. Conclusion PHH3 immunostain can simplify counting of mitotic figures in cutaneous smooth muscle neoplasms, especially those with many pyknotic nuclei, and may help to reduce interobserver variability. Ki-67 staining may also be of help in establishing a diagnosis of LMS.

Background Fluorescence of pathogenic fungi has been previously shown when hematoxylin and eosin-stained sections are examined under a fluorescent microscope. We hypothesize that this phenomenon could aid in the evaluation of nail specimens for onychomycosis. Methods Forty-eight routinely stained nail sections of periodic acid-Schiff (PAS)-positive onychomycosis, along with 23 PAS-negative control specimens with a clinical diagnosis of onychomycosis, were studied under a fluorescent microscope to determine the clinical usefulness of this technique. Results In most cases, fluorescence of fungal organisms was noted. Fungi were identified by their tubular or annular shapes with fluorescence surrounding them. The sensitivity and specificity of the method were 96 and 90%, respectively. In some cases, it was difficult to identify the fungi because of the relative paucity of organisms, weak fluorescence and high background fluorescence of eosinophilic nail keratin. Conclusions We conclude that fluorescence microscopy can be used as a rapid screening tool for identification of fungi in nail specimens.

Follicular differentiation can be exhibited by a variety of epidermal lesions. We report an example of panfolliculoma purely confined to the epidermis. The lesion presented as a verrucous plaque on the leg of a 55-year-old man. Histopathologic sections showed an acanthoma with follicular differentiation including areas mimicking the follicular germ, matrix, root sheath and infundibular components.

Background Erythema Nodosum Leprosum (ENL) is a serious complication of leprosy. It is normally treated with high dose steroids, but its recurrent nature leads to prolonged steroid usage and associated side effects. There is little evidence on the efficacy of alternative treatments for ENL, especially for patients who have become steroid resistant or have steroid side effects. These two pilot studies compare the efficacy and side effect profile of ciclosporin plus prednisolone against prednisolone alone in the treatment of patients with either new ENL or chronic and recurrent ENL. Methods and Results Thirteen patients with new ENL and twenty patients with chronic ENL were recruited into two double-blinded randomised controlled trials. Patients were randomised to receive ciclosporin and prednisolone or prednisolone treatment only. Patients with acute ENL had a delay of 16 weeks in the occurrence of ENL flare-up episode, with less severe flare-ups and decreased requirements for additional prednisolone. Patients with chronic ENL on ciclosporin had the first episode of ENL flare-up 4 weeks earlier than those on prednisolone, as well as more severe ENL flare-ups requiring 2.5 times more additional prednisolone. Adverse events attributable to prednisolone were more common that those attributable to ciclosporin. Conclusions This is the first clinical trial on ENL management set in the African context, and also the first trial in leprosy to use patients’ assessment of outcomes. Patients on ciclosporin showed promising results in the management of acute ENL in this small pilot study. But ciclosporin, did not appear to have a significant steroid–sparing effects in patients with chronic ENL, which may have been due to the prolonged use of steroids in these patients in combination with a too rapid decrease of steroids in patients given ciclosporin. Further research is needed to determine whether the promising results of ciclosporin in acute ENL can be reproduced on a larger scale., Author Summary Leprosy is caused by a mycobacterium, and is curable with multi-drug therapy, a combination of antibiotics taken for 6 or 12 months. However, some leprosy patients develop an inflammatory condition known as erythema nodosum leprosum (ENL), or Type 2 reaction. ENL affects multiple organs and causes systemic illness as well as nerve damage that leads to disability and deformity. ENL is often chronic and patients have multiple flare-ups requiring prolonged steroid treatment. Patients are at risk of developing adverse events related to long term steroids. There are no effective, non-teratogenic alternative treatments for patients who no longer respond to steroids or have contra-indications to steroids. We conducted two studies to see if ciclosporin, an immunosuppressant used in many inflammatory conditions, could safely be used either as an alternative or in conjunction with prednisolone to treat ENL. Patients with acute ENL showed promising results with ciclosporin treatment, with a 16 week median delay in recurrence of ENL. It did not however appear to have a significant steroid–sparing effects in patients with chronic ENL. This suggests that further ENL studies should look at carefully tailored regimens of medication in order to assess the effect of ciclosporin or other immunosuppressant drugs.

The effect of an ultraviolet generated ozone treatment (UV/O3), on the surface and near surface functionality and structure of polyacrylonitrile based carbon fibres has been studied using X-ray photoelectron spectroscopy (XPS), scanning electron microscopy, and Raman spectroscopy. Results were compared to electrochemically treated fibres. The UV/O3 treated fibres showed increased levels of oxygen functionalities. Levels of oxygen comparable to a high level electrochemical shear treatment were achieved within 5 min of treatment (O/C 0.11 ± 0.03 for both treatments). XPS O1s/C1s ratios as high as 0.3 were produced, with saturation occurring at approximately 40 min exposure. The main functional groups introduced were, in addition to hydroxyl species, alkoxides (ca. 286.5 eV), carbonyl (288.0 eV), and carboxyl (289.5 eV). Examination of the full width half maximum of the graphite peak from XPS C1s showed some disorder was introduced to the first few layers of the fibre with treatment but the effect was not evident in the Raman, i.e. in the bulk of the fibre.

The adsorption modes and stability of the amino acid alanine (NH 2 –CH(CH 3 )–COOH) have been studied on the nonpolar single crystal surface of zinc oxide, ZnO ( 1 0 1 ¯ 0 ) , experimentally by X-ray photoelectron spectroscopy (XPS) and computationally using density functional theory (DFT). Deposition at 200 K was found to lead to the formation of multilayers identified by an XPS N1s peak at 401.7 eV assigned to the NH 3 + group, a fingerprint of the zwitterionic structure of alanine in the solid state. Heating to 300 K resulted in the removal of most of the multilayers with the remaining surface coverage estimated to 0.4 with respect to Zn cations. At this temperature most of the alanine molecules are found to be deprotonated (dissociated), yielding a carboxylate species (NH 2 –CH(CH 3 )–COO − (a) + O H (s); where O is surface oxygen, (a) for adsorbed and (s) for surface species). Further heating of the surface resulted in a gradual decrease of the surface coverage and by 500 K a large fraction of adsorbed alanine molecules have desorbed from the surface. Total energy DFT computations of different adsorbate species identified two stable dissociative adsorption modes: bidentate and monodentate. The bidentate species with adsorption energy of 1.75 eV was found to be more stable than the monodentate species by about 0.7 eV.

The work presents a study of the formation of defects created by argon ion sputtering of UO{sub 2} thin film surfaces using high-resolution X-ray photoelectron spectroscopy with photon energy of 625 eV. Stable-defected surfaces of UO{sub 2-x} were monitored by the uranium core level lines found at the low-binding energy side of the U{sup +4} features. The lower end of these states gave binding energies at 377.1 and 387.7 eV attributed to U4f{sub 7/2} and U4f{sub 5/2} core levels peaks, respectively, for metallic uranium (U{sup {circ}}). In between both states (U{sup {circ}} and U{sup +4}), the clear presence of other electronic states is observed. These lines are attributed to intermediate, metastable states of uranium ions between U{sup {circ}} and U{sup +4}. Temperature-programmed X-ray photoelectron spectroscopy is performed to observe the oxidation process of these reduced states with increasing temperature. The increase in the U{sup +4} intensity is not correlated with the decrease of U ions signal with lower oxidation states indicating that the limitation is the photoelectron escape depth. In other words, sputtering has created reduced clusters or ridges on the surface of average dimensions larger than the escape depth of the 4f photoelectron with kinetic energy of 225 eV.more » The activation energy for surface oxidation to U{sup +4} is {approx}20 kJ mol{sup -1}. This value is close to other values reported for vacancy-type diffusion mechanism in the fluorite structure.« less

Some examples of Bowen disease lack the characteristic broad parakeratosis making their histopathologic diagnosis particularly difficult in small and incomplete biopsies.The archives of our dermatopathology laboratory were searched for cases of Bowen disease with75% orthokeratosis (orthokeratotic Bowen disease) and classic Bowen disease (25% parakeratosis). Selected specimens were evaluated histopathologically, using immunohistochemical stains (CK10, CK7, Bcl-2, p16 and Ki-67) and by DNA amplification/sequencing for human papilloma virus (HPV) subtypes.Among 102 consecutive samples 14 cases of orthokeratotic Bowen disease were identified. In comparison with 24 examples of classic Bowen disease, the orthokeratotic examples occurred more frequently in female and younger patients (p = 0.04 and 0.008, respectively) but shared most of the histopathologic features of classic Bowen disease except a preserved granular layer and relative absence of the eyeliner sign (p 0.0001 and p = 0.042, respectively). Immunohistochemical staining patterns were similar between the two groups. HPV types 11, 16 and 58 were identified from five cases of orthokeratotic Bowen disease.Orthokeratotic Bowen disease is a distinct variant of squamous cell carcinoma in situ associated with HPV infection in less than half of the cases studied.

Background Nevoid melanoma may be confused both clinically and histologically with benign nevi. Objective The aim of this study was to characterize the histologic features of nevoid melanoma. Methods Forty-three cases of nevoid melanoma from our laboratory were evaluated. Results Our study cases included 33 men and 10 women with mean age of 62 years. The back was the most common site followed by the arm. A clinical diagnosis other than melanoma was made in about 40% of the cases. Two architectural patterns were identified: Plaque and polypoid. Sheetlike confluence of melanocytes expanding the papillary dermis was seen in 60% of the cases. Nests disposed in parallel arrays at the base of the tumor (parallel theque pattern) were present in roughly 81% of our series. Mitoses were evident in one-third of cases ranging from less than 1 to 4 per square millimeter. Genomic abnormalities characteristic of melanoma were detected in 7 of 8 tested cases. Limitation This is a descriptive study. No follow-up information was available for 32 of the 43 patients. In the other 11, follow-up was limited to the re-excision specimens. Conclusion Characteristic growth patterns including confluence of dermal melanocytes with no intervening connective tissue and the parallel theque pattern can be helpful in suggesting a diagnosis of nevoid melanoma at scanning magnification.

Hydrogen is one of the most widely used chemical elements in the world. It is currently being used in many different industries, from chemical and refining to metallurgical, food, glass, and electronics. Because of its light weight and high energy density, hydrogen is also a preferred fuel in space applications, as a clean fuel in fuel cells. This chapter provides a brief overview of hydrogen and its physical and chemical properties. The history of hydrogen and its discovery, electronic structure, position in the periodic table, and its periodic properties are described. The energy density of hydrogen is compared with some of the common hydrocarbons such as natural gas and other liquid fuels such as methanol and ethanol. A few common methods for industrial production of hydrogen and synthesis gas, which is a mixture of hydrogen and carbon monoxide, and their uses for the manufacture of variety of chemicals and fuels are highlighted.

The adsorption of CO onto the hydroxylated α-Al2O3(0001) surface was studied using density functional theory (DFT). Dissociated adsorption of water was found to be stable, with an adsorption energy (Ea) of 1.62 eV at θ(water) = 0.75. The most stable hydroxylation form on the clean surface was found to be in the 1-2 dissociation configuration, where the OH group binds to a surface Al ion and the H ion binds to one of the three equivalent surface O ions. The adsorption energy of CO was found to be dependent on the degree of pre-hydroxylation of the surface as well as on the CO coverage. The highest adsorption energy of CO was found when θ(CO) = 0.25 on a pre-hydroxylated surface with θ(water) = 0.25; Ea = 0.57 eV. The adsorption energy of CO decreased upon increasing the degree of pre-hydroxylation. The vibrational frequency of ν(CO) was also computed and in all cases it was blue shifted with respect to gas-phase CO. The shift, Δν, decreased with increasing CO coverage but increased with increasing surface hydroxylation. A comparison with available experimental work is discussed.

Ethanol (EtOH) and methyl tert-butyl ether (MTBE) are finding increasing use as fuel additives because of governmental mandates, and the relative merits of each have therefore become the focus of intense debate. The ultimate fate of fugitive emissions of these species forms one aspect of this controversy, because EtOH has been implicated in reductions in air quality, while MTBE has been linked to human illness. Both species have been shown to photoreact rapidly on fly ash particles in urban atmospheres. This work reports kinetic studies as well as detailed surface and bulk characterizations of fly ash by XRD, XPS, and SEM/EDA. The active phases in fly ash are probably Fe and Ti oxides. Addition of water to the reactant gas in some cases more than doubled the reaction rate of EtOH, but hardly affected that rate of MTBE. To gain insight into the respective roles of Fe, Ti, and alkali metals, kinetics were also measured over alkali-modified TiO2 (anatase). Addition of Na or Ca oxides shifted the reaction product of EtOH from total oxidation (CO2) to partial oxidation (acetaldehyde).

Pulsed dye laser treatment often results in port-wine stain (PWS) improvement; however, results vary. A frequency-doubled neodymium-doped yttrium aluminum garnet (Nd:YAG) laser that allows for shorter pulse widths along with large spot sizes and high fluences has been developed for the treatment of cutaneous vascular lesions.A prospective, controlled study was performed in 5 adults with PWS using a frequency-doubled Nd:YAG laser (Excel V; Cutera Inc, Brisbane, CA) in 4 quadrants, using spot sizes of 6 to 10 mm, fluences of 4.8 to 9 J/cm2, and pulse durations of 3 to 6 ms. An adjacent control area was not treated. Each was assessed immediately posttreatment for purpura and edema and at 1 month for PWS color, size, texture, and thickness. Skin biopsies obtained immediately after and at 1 month posttreatment were evaluated.All treatment quadrants displayed purpura. At 1-month follow-up, all treatment quadrants showed at least 1 grade of color improvement, from a minimum of 1% to 25% to a maximum of 51% to 75% improvement (12/20 quadrants with 1%-25% improvement, 3/20 with 26%-50%, 5/20 with 51%-75%, and 0/20 with 76%-100%). Histologic evaluation of treatment quadrants revealed vascular changes ranging 0.35 to 4 mm in depth. Immediately posttreatment, thrombi and extravasated red blood cells were observed in treatment quadrants. Histology at 1 month revealed decreased number and diameter of vessels in treatment quadrants (superficial vessels decreased by mean 1.1 vessels per section [13%], and diameter by 3.0 μm [47%], midlevel vessels decreased in number by 2.3 [20%], diameter by 2.42 μm [25%], and deep vessels decreased in number by 1.5 [83%], and diameter by 7.44 μm [88%]).A single treatment with a short pulse width, frequency-doubled Nd:YAG laser resulted in safe and effective improvement of PWS, with up to 75% improvement in color observed at 1 month. Histologic evaluation demonstrated vascular injury at depths of 0.35 to 4 mm with a reduction in vessel number and size at multiple dermal levels.

Ethanol and methyl tert‐butyl ether (MTBE) are finding increasing use as fuel additives in the U.S. because of governmental mandates, and the relative merits of each have therefore become the focus of intense debate. The ultimate fate of fugitive emissions of these species forms one aspect of this controversy, because ethanol has been implicated in reductions in air quality, while MTBE has been linked to human illness. Both species are known to react homogeneously with photogenerated OH radicals. Here we show that both can also photoreact on fly ash and related particulates present ubiquitously in urban tropospheres. The heterogeneous reactions involving MTBE ultimately form formaldehyde and acetone at rates comparable to purely homogeneous pathways, demonstrating for the first time the existence of a significant catalytic process on tropospheric particulates having widespread spatial distribution. Oxides of Ti and Fe drive the reaction.

The mitotic index is important in the assessment of tumors such as leiomyoma (LM) and leiomyosarcoma (LMS), which may exhibit a range of cytological atypia. The mitotic marker phosphohistone-H3 (PHH3) was shown to improve interobserver and intraobserver variability in many tumors.We evaluated the mitotic index in 20 pilar LM and cutaneous LMS using PHH3 and hematoxylin and eosin (HE)-stained sections. Ki-67 staining characteristics of the tumors were also assessed.Mitotic figures were more easily identified within PHH3 sections. The mitotic index per 10 high power fields (HPF) on the PHH3 stain was slightly higher than HE both in the LM (mean 0.1, range 0-1 vs. mean 0) and LMS groups (mean 8.6 vs. 8.0 with range of 1-24 for both stains). The difference in mitotic index between the two stains was not statistically significant in either group (p = 0.7). The Ki-67 proliferative index showed a statistically significant correlation with a diagnosis of LMS.PHH3 immunostain can simplify counting of mitotic figures in cutaneous smooth muscle neoplasms, especially those with many pyknotic nuclei, and may help to reduce interobserver variability. Ki-67 staining may also be of help in establishing a diagnosis of LMS.

Fluorescence of pathogenic fungi has been previously shown when hematoxylin and eosin-stained sections are examined under a fluorescent microscope. We hypothesize that this phenomenon could aid in the evaluation of nail specimens for onychomycosis.Forty-eight routinely stained nail sections of periodic acid-Schiff (PAS)-positive onychomycosis, along with 23 PAS-negative control specimens with a clinical diagnosis of onychomycosis, were studied under a fluorescent microscope to determine the clinical usefulness of this technique.In most cases, fluorescence of fungal organisms was noted. Fungi were identified by their tubular or annular shapes with fluorescence surrounding them. The sensitivity and specificity of the method were 96 and 90%, respectively. In some cases, it was difficult to identify the fungi because of the relative paucity of organisms, weak fluorescence and high background fluorescence of eosinophilic nail keratin.We conclude that fluorescence microscopy can be used as a rapid screening tool for identification of fungi in nail specimens.

Langerhans' cell histiocytosis represents a diverse group of rare disorders characterized by proliferation and infiltration of various organs by bone marrow-derived abnormal Langerhans' cells. These diorders exhibit varied patterns of organ involvement, age distribution, prognosis and clinical manifestation. Here in we discuss an adult presentation of the disease in a 43 years old lady and summarize the latest recommendations regarding the classification, pathogenesis, work up and treatment of adult patients with these disorders.

Follicular differentiation can be exhibited by a variety of epidermal lesions. We report an example of panfolliculoma purely confined to the epidermis. The lesion presented as a verrucous plaque on the leg of a 55-year-old man. Histopathologic sections showed an acanthoma with follicular differentiation including areas mimicking the follicular germ, matrix, root sheath and infundibular components.

Elastic fibers are important components of the skin and are responsible for skin elasticity. Genetic defects are well-known in numerous hereditary elastic tissue disorders and skin biopsies are often the first step in the evaluation of those disorders. Verhoeff-Van Gieson elastic staining is a simple method that is used for visualizing elastic fibers. With the development of modern immunohistochemical methods, the value of routine histochemical staining is sometimes underestimated. Histochemical stains are less expensive, easy to perform and help to resolve numerous diagnostic quandaries in dermatopathology. This article focuses on the value of elastic tissue staining in dermatopathology, with a focus on primary elastic tissue disorders, alopecia, inflammatory skin disorders and neoplastic proliferations.

Catalytic hydrogen production from renewables is a promising method for providing energy carriers in the near future. Photocatalysts capable of promoting this reaction are often composed of noble metal nanoparticles deposited on a semiconductor. The most promising semiconductor at present is TiO₂. The successful design of these catalysts relies on a thorough understanding of the role of the noble metal particle size and the TiO₂ polymorph. Here we demonstrate that Au particles in the size range 3-30 nm on TiO₂ are very active in hydrogen production from ethanol. It was found that Au particles of similar size on anatase nanoparticles delivered a rate two orders of magnitude higher than that recorded for Au on rutile nanoparticles. Surprisingly, it was also found that Au particle size does not affect the photoreaction rate over the 3-12 nm range. The high hydrogen yield observed makes these catalysts promising materials for solar conversion.

The adsorption modes and stability of the amino acid alanine (NH(2)-CH(CH(3))-COOH) have been studied on the nonpolar single crystal surface of zinc oxide, ZnO(1010), experimentally by X-ray photoelectron spectroscopy (XPS) and computationally using density functional theory (DFT). Deposition at 200 K was found to lead to the formation of multilayers identified by an XPS N1s peak at 401.7 eV assigned to the NH(3)(+) group, a fingerprint of the zwitterionic structure of alanine in the solid state. Heating to 300 K resulted in the removal of most of the multilayers with the remaining surface coverage estimated to 0.4 with respect to Zn cations. At this temperature most of the alanine molecules are found to be deprotonated (dissociated), yielding a carboxylate species (NH(2)-CH(CH(3))-COO(-) (a) + OH (s); where O is surface oxygen, (a) for adsorbed and (s) for surface species). Further heating of the surface resulted in a gradual decrease of the surface coverage and by 500 K a large fraction of adsorbed alanine molecules have desorbed from the surface. Total energy DFT computations of different adsorbate species identified two stable dissociative adsorption modes: bidentate and monodentate. The bidentate species with adsorption energy of 1.75 eV was found to be more stable than the monodentate species by about 0.7 eV.

There have been few studies on the characterisation of anodic aluminium oxide (AAO) membranes and AAO-based nanocomposite. For example, investigations of the effects of humidity and heat treatment on surfaces of the NAAO membrane have provided significant implications for different applications of this material, for example in catalysis, chemical sensing, filtration applications, asymmetric epoxidation and template synthesis such as nanowire and nanotube arrays. This study investigates morphological properties of NAAO membrane using fractal methods and attempts to establish various relationships between geometrical based characterisations using microstructure images with the physico-chemistry properties of the material. To date, fractal concepts have provided powerful tools for describing different physical properties for nanomaterial. Box counting technique is used to determine the fractal dimension of palladium (Pd) nanoparticle distributed in NAAO membrane's SEM binary images. The relation between fractal dimension and Pd nanoparticle size distribution is examined.