Evolution of optical properties of chromium spinels CdCr2_2O4_4, HgCr2_2S4_4, and ZnCr2_2Se4_4 under high pressure

We report pressure-dependent reflection and transmission measurements on ZnCr$_2$Se$_4$, HgCr$_2$S$_4$, and CdCr$_2$O$_4$ single crystals at room temperature over a broad spectral range 200-24000 cm$^{-1}$. The pressure dependence of the phonon modes and the high-frequency electronic excitations indicates that all three compounds undergo a pressure-induced structural phase transition with the critical pressure 15 GPa, 12 GPa, and 10 GPa for CdCr$_2$O$_4$, HgCr$_2$S$_4$, and ZnCr$_2$Se$_4$, respectively. The eigenfrequencies of the electronic transitions are very close to the expected values for chromium crystal-field transitions. In the case of the chalcogenides pressure induces a red shift of the electronic excitation which indicates a strong hybridization of the Cr d-bands with the chalcogenide bands.Comment: Accepted for publication in Phys. Rev.

The impact of mucosal infections on acquisition and progression of tuberculosis

More than one-third of the world\u27s population, or over 2 billion people, are infected with Mycobacterium tuberculosis, the causative pathogen of tuberculosis in humans. Why only 10% of those infected develop active disease while the remainder harbor latent infection remains one of the greatest scientific and public health mysteries. Bacterial persistence is characterized by a dynamic state of immunological tolerance between pathogen and host. The critical role of CD4(+) T cells in defense against intracellular pathogens became evident during epidemiological studies of HIV-1 infection, which showed a clear inverse relationship between CD4(+) T-cell count in peripheral blood and increased risk of infection with M. tuberculosis, pneumocystis and Toxoplasma gondii. There is also growing evidence of a common mucosal immune system, whereby immune cells activated at one mucosal site may disseminate to remote effector sites. In this commentary, we review emerging evidence from human studies that the outcome of M. tuberculosis infection is influenced by concurrent mucosal infections, using Helicobacter pylori and geohelminths as examples. Understanding how the complexity of microbial exposures influences host immunity may have important implications for vaccine development and therapeutic interventions

Diacritics improve comprehension of the Arabic script by providing access to the meanings of heterophonic homographs

The diacritical markers that represent most of the vowels in the Arabic orthography are generally omitted from written texts. Previous research revealed that the absence of diacritics reduces reading comprehension performance even by skilled readers of Arabic. One possible explanation is that many Arabic words become ambiguous when diacritics are missing. Words of this kind are known as heterophonic homographs and are associated with at least two different pronunciations and meanings when written without diacritics. The aim of the two experiments reported in this study was to investigate whether the presence of diacritics improves the comprehension of all written words, or whether the effects are confined to heterophonic homographs. In Experiment 1, adult readers of Arabic were asked to decide whether written words had a living meaning. The materials included heterophonic homographs that had one living and one non-living meaning. Results showed that diacritics significantly increased the accuracy of semantic decisions about ambiguous words but had no effect on the accuracy of decisions about unambiguous words. Consistent results were observed in Experiment 2 where the materials comprised sentences rather than single words. Overall, the findings suggest that diacritics improve the comprehension of heterophonic homographs by facilitating access to semantic representations that would otherwise be difficult to access from print

Adherence to Lifestyle Advice and reatments in Pakistani Patients with Type 2 Diabetes Mellitus.

Background: Type 2 diabetes mellitus (T2DM) is a chronic disease that has become a major health care concern, especially in developing countries like Pakistan. Lifestyle modification and appropriate pharmacotherapy are shown to improve blood glucose levels, lipid abnormalities and blood pressure. It is not known how many patients adhere to advice and drugs prescribed. This study aimed to determine adherence to lifestyle and therapeutic advice. Methods: A cross sectional hospital based study was conducted among patients attending the diabetic clinic at the Aga Khan University Hospital, using a structured questionnaire. Adult patients with T2DM and with at least one year duration of diabetes were included in the study. Results: Participants were aged between 32 and 92 years old with a mean age of 55.7 years old (SD ± 10.7). Mean duration of diabetes was 10.7 years old (SD ± 7.7). Majority (94%) of the patients were literate. Around half (47.3%) of the patients have had achieved glycemic target (HbA1c \u3c 7%). Above target glycemic control was more common among patients with ischemic heart disease (68.1%), neuropathy (64.8%) and those on insulin (62.5%). Self-reported non-adherence for blood sugar monitoring (9.5%), physi cal activity (61.7%), tobacco use (43.4%) and foot care (43.9%) were noted. About 25% of the participants were not fully adherent to dietary advice. None of the patients from our study reported non-ad- herence to medications. Good adherence to physical activity was found in males with college degree. The highest percentage of tobacco use (33.3%) was reported among businessmen. Conclusion: We noted low adherence to advice for physical activity, tobacco use and SMBG, but a high adherence to prescribed medications and insulin. This was a selected group visiting a teaching hospital. This will need to be studied further in the community and efforts are required to motivate patients

Concentrations of Polychlorinated Biphenyls (PCB’s), Chlorinated Pesticides, and Heavy Metals and Other Elements in Tissues of Belugas, Delphinapterus leucas, from Cook Inlet

Tissues from Cook Inlet beluga whales, Delphinapterus leucas, that were collected as part of the Alaska Marine Mammal Tissue Archival Project were analyzed for polychlorinated biphenyls (PCB’s), chlorinated pesticides, and heavy metals and other elements. Concentrations of total PCB’s (ΣPCB’s), total DDT (ΣDDT), chlordane compounds, hexachlorobenzene (HCB), dieldrin, mirex, toxaphene, and hexachlorocyclohexane (HCH) measured in Cook Inlet beluga blubber were compared with those reported for belugas from two Arctic Alaska locations (Point Hope and Point Lay), Greenland, Arctic Canada, and the highly contaminated stock from the St. Lawrence estuary in eastern Canada. The Arctic and Cook Inlet belugas had much lower concentrations (ΣPCB’s and ΣDDT were an order of magnitude lower) than those found in animals from the St. Lawrence estuary. The Cook Inlet belugas had the lowest concentrations of all (ΣPCB’s aver-aged 1.49 ± 0.70 and 0.79 ± 0.56 mg/kg wet mass, and ΣDDT averaged 1.35 ± 0.73 and 0.59 ± 0.45 mg/kg in males and females, respectively). Concentrations in the blubber of the Cook Inlet males were significantly lower than those found in the males of the Arctic Alaska belugas (ΣPCB’s and ΣDDT were about half). The lower levels in the Cook Inlet animals might be due to differences in contaminant sources, food web differences, or different age distributions among the animals sampled. Cook Inlet males had higher mean and median concentrations than did females, a result attributable to the transfer of these compounds from mother to calf during pregnancy and during lactation. Liver concentrations of cadmium and mercury were lower in the Cook Inlet belugas (most cadmium values were <1 mg/kg and mercury values were 0.704–11.42 mg/kg wet mass), but copper levels were significantly higher in the Cook Inlet animals (3.97–123.8 mg/kg wet mass) than in Arctic Alaska animals and similar to those reported for belugas from Hudson Bay. Although total mercury levels were the lowest in the Cook Inlet population, methylmercury concentrations were similar among all three groups of the Alaska animals examined (0.34–2.11 mg/kg wet mass). As has been reported for the Point Hope and Point Lay belugas, hepatic concentrations of silver were r

Facial Onset Sensory and Motor Neuronopathy: A Case Series and Literature Review

Introduction: Facial Onset Sensory and Motor Neuronopathy (FOSMN) typically presents with paresthesias in the trigeminal nerve distribution and weakness that progresses rostro-caudally. Objective: To present two new cases of FOSMN, summarize the current literature, and address areas for future study. Methods: Observational data was collected from two patients with FOSMN from our institution. A literature review of FOSMN was completed using PubMed. Results: We identified 100 cases of FOSMN, including our two new cases. 93% presented with facial paresthesias. 97% had bulbar symptoms. Five had family history of ALS. Abnormal Blink reflex was most common on EMG/NCS. CSF was typically normal, but a rare severe case showed elevated protein. Mutations included: TARDBP, OPMD, D90A-SOD1, CHCHD10, VCP, and SQSTM1. Neuropathological studies showed neurodegenerative changes without inflammation. Some cases have reported transient stabilization or improvement to immunomodulatory therapy. Case Reports: A 72-year-old man presented with right-sided trigeminal paresthesias that progressed in a rostro-caudal fashion, dysphagia, and hand weakness. He died 4-5 years after symptom onset. A 69-year-old man presented with left-sided jaw paresthesias, dysphagia and dysarthria. He was trialed on IVIG for 1.5 years without improvement and died 2.6 years after symptom onset. Conclusion: FOSMN is a rare disorder with a unique clinical and electrophysiological phenotype. The pathophysiology has been associated with neurodegeneration and multiple gene mutations have correlated to FOSMN. Some reports suggest transient response to immunomodulatory therapy, though prospective studies are lacking. CSF protein elevation may be seen in severe disease. Future studies will help further elucidate the approach to diagnosis, treatment, and prognostic counseling (biomarkers). &nbsp

Effect of high pressure on multiferroic BiFeO3

We report experimental evidence for pressure instabilities in the model multiferroic BiFeO3 and namely reveal two structural phase transitions around 3 GPa and 10 GPa by using diffraction and far-infrared spectroscopy at a synchrotron source. The intermediate phase from 3 to 9 GPa crystallizes in a monoclinic space group, with octahedra tilts and small cation displacements. When the pressure is further increased the cation displacements (and thus the polar character) of BiFeO3 is suppressed above 10 GPa. The above 10 GPa observed non-polar orthorhombic Pnma structure is in agreement with recent theoretical ab-initio prediction, while the intermediate monoclinic phase was not predicted theoretically.Comment: new version, accepted for publication in Phys. Rev.

Lifetime corneal edema load model

Purpose: To highlight the potential benefits for long-term use of silicone hydrogels daily disposable (DD) contact lenses, particularly with patients who are noncompliant, sleeping or napping while wearing their lenses, or those who have higher oxygen demands and wear this modality for decades. Methods: Published data for corneal swelling with lenses and no lens wear were used to develop a nonlinear least squares model. The edema load experienced with a range of oxygen transmissibilities (Dk/t) and wear compliance (sleep and napping) was determined. A mixed-effects linear regression model was used to compare the edema load for high and average corneal swellers. Results: The edema load generated demonstrates that a high Dk/t silicone hydrogel lens results in edema levels close to that with no lens wear. In comparison, hydrogels with a Dk/t of 27 (×10−9 [cm mL{O2}][s mLmmHg]), worn on a daily wear schedule will result in 1.5 times more edema and up to two times more if the patient is noncompliant over each decade of wear. High swellers after four decades of wear will have an edema load 10 to 17 times greater than average swellers depending on Dk/t and their degree of noncompliance with the daily wear modality. Conclusions: Prescribing silicone hydrogelDDlenses, particularly with higher DK/t,may help to maintain the long-term ocular health of patients, when they wear their lenses fulltime for many decades. Translational Relevance: Illustrates the importance of Dk/t for any CL wear modality where patients nap or sleep in lenses or have high oxygen needs

Titanium hardware extrusion following pediatric cranioplasty

Aging pediatric cranioplasty patients with titanium implants are a population at risk for scalp breakdown and implant extrusion. Complications from titanium use in adult cranioplasty patients are well documented in the medical literature. Reports of complications focused on pediatric populations are sparse. In this case series, we report two examples of negative sequelae associated with titanium utilization in infant cranioplasty and discuss our treatment strategy for each case