New Chiral Phases of Superfluid 3He Stabilized by Anisotropic Silica Aerogel

A rich variety of Fermi systems condense by forming bound pairs, including high temperature [1] and heavy fermion [2] superconductors, Sr2RuO4 [3], cold atomic gases [4], and superfluid 3He [5]. Some of these form exotic quantum states having non-zero orbital angular momentum. We have discovered, in the case of 3He, that anisotropic disorder, engineered from highly porous silica aerogel, stabilizes a chiral superfluid state that otherwise would not exist. Additionally, we find that the chiral axis of this state can be uniquely oriented with the application of a magnetic field perpendicular to the aerogel anisotropy axis. At suffciently low temperature we observe a sharp transition from a uniformly oriented chiral state to a disordered structure consistent with locally ordered domains, contrary to expectations for a superfluid glass phase [6].Comment: 6 pages, 4 figure, and Supplementary Informatio

High-efficiency photovoltaic cells with wide optical band gap polymers based on fluorinated phenylene-alkoxybenzothiadiazole

A series of semi-crystalline, wide band gap (WBG) photovoltaic polymers were synthesized with varying number and topology of fluorine substituents. To decrease intramolecular charge transfer and to modulate the resulting band gap of D-A type copolymers, electron-releasing alkoxy substituents were attached to electron-deficient benzothiadiazole (A) and electron-withdrawing fluorine atoms (0-4F) were substituted onto a 1,4-bis(thiophen-2-yl)benzene unit (D). Intra- and/or interchain noncovalent Coulombic interactions were also incorporated into the polymer backbone to promote planarity and crystalline intermolecular packing. The resulting optical band gap and the valence level were tuned to 1.93-2.15 eV and -5.37 to -5.67 eV, respectively, and strong interchain organization was observed by differential scanning calorimetry, high-resolution transmission electron microscopy and grazing incidence X-ray scattering measurements. The number of fluorine atoms and their position significantly influenced the photophysical, morphological and optoelectronic properties of bulk heterojunctions (BHJs) with these polymers. BHJ photovoltaic devices showed a high power conversion efficiency (PCE) of up to 9.8% with an open-circuit voltage of 0.94-1.03 V. To our knowledge, this PCE is one of the highest values for fullerene-based single BHJ devices with WBG polymers having a band gap of over 1.90 eV. A tandem solar cell was also demonstrated successfully to show a PCE of 10.3% by combining a diketopyrrolopyrrole-based low band gap polymer

Enumeration of CD4+ T-Cells Using a Portable Microchip Count Platform in Tanzanian HIV-Infected Patients

Background CD4+ T-lymphocyte count (CD4 count) is a standard method used to monitor HIV-infected patients during anti-retroviral therapy (ART). The World Health Organization (WHO) has pointed out or recommended that a handheld, point-of-care, reliable, and affordable CD4 count platform is urgently needed in resource-scarce settings. Methods HIV-infected patient blood samples were tested at the point-of-care using a portable and label-free microchip CD4 count platform that we have developed. A total of 130 HIV-infected patient samples were collected that included 16 de-identified left over blood samples from Brigham and Women's Hospital (BWH), and 114 left over samples from Muhimbili University of Health and Allied Sciences (MUHAS) enrolled in the HIV and AIDS care and treatment centers in the City of Dar es Salaam, Tanzania. The two data groups from BWH and MUHAS were analyzed and compared to the commonly accepted CD4 count reference method (FACSCalibur system). Results The portable, battery operated and microscope-free microchip platform developed in our laboratory (BWH) showed significant correlation in CD4 counts compared with FACSCalibur system both at BWH (r = 0.94, p<0.01) and MUHAS (r = 0.49, p<0.01), which was supported by the Bland-Altman methods comparison analysis. The device rapidly produced CD4 count within 10 minutes using an in-house developed automated cell counting program. Conclusions We obtained CD4 counts of HIV-infected patients using a portable platform which is an inexpensive (<$1 material cost) and disposable microchip that uses whole blood sample (<10 µl) without any pre-processing. The system operates without the need for antibody-based fluorescent labeling and expensive fluorescent illumination and microscope setup. This portable CD4 count platform displays agreement with the FACSCalibur results and has the potential to expand access to HIV and AIDS monitoring using fingerprick volume of whole blood and helping people who suffer from HIV and AIDS in resource-limited settings.Wallace H. Coulter Foundation (Young Investigation Award in Bioengineering Award)National Institutes of Health (U.S.) (NIH R01AI081534)National Institutes of Health (U.S.) (NIH R21AI087107)National Institutes of Health (U.S.) (NIH grant RR016482)National Institutes of Health (U.S.) (grant AI060354)National Institutes of Health (U.S.) (NIH Fogarty Fellowship

A comparison of surgical outcomes between endoscopic and robotically assisted thyroidectomy: the authors’ initial experience

Background: The gasless, transaxillary endoscopic thyroidectomy (GTET) offers a distinct advantage over the conventional open operation by leaving no visible neck scar, and in an attempt to improve its ergonomics and surgical outcomes, the robotically assisted thyroidectomy (RAT) was introduced. The RAT uses the same endoscopic route as the GTET but with the assistance of the da Vinci S robotic system. Excellent results for RAT have been reported, but it remains unclear whether RAT offers any potential benefits over GTET. Methods: From June to December 2009, 46 patients underwent endoscopic thyroidectomy. Of these patients, 39 had surgery without the robot (GTET) and 7 had surgery with the robot (RAT). Demographics, surgical indications, operative findings, and postoperative outcomes were compared between the two groups. All the patients were followed up for at least 6 months after surgery. Results: Patient demographics, surgical indications, and extent of resection were similar between the two groups. The median total procedure time was significantly longer for RAT (149 min) than for GTET (100 min; p = 0.018), but the contralateral recurrent laryngeal nerve was more likely to identified in RAT (100%) than in GTET (42.9%; p = 0.070). On the average, GTET needed one more surgical assistant than RAT (1 vs. 0; ppublished_or_final_versionSpringer Open Choice, 21 Feb 201

Reviewing progress: 7 Year Trends in Characteristics of Adults and Children Enrolled at HIV Care and Treatment Clinics in the United Republic of Tanzania.

To evaluate the on-going scale-up of HIV programs, we assessed trends in patient characteristics at enrolment and ART initiation over 7 years of implementation. Data were from Optimal Models, a prospective open cohort study of HIV-infected (HIV+) adults (>=15 years) and children (<15 years) enrolled from January 2005 to December 2011 at 44 HIV clinics in 3 regions of mainland Tanzania (Kagera, Kigoma, Pwani) and Zanzibar. Comparative statistics for trends in characteristics of patients enrolled in 2005--2007, 2008--2009 and 2010--2011 were examined. Overall 62,801 HIV+ patients were enrolled: 58,102(92.5%) adults, (66.5% female); 4,699(7.5%) children.Among adults, pregnant women enrolment increased: 6.8%, 2005--2007; 12.1%, 2008--2009; 17.2%, 2010--2011; as did entry into care from prevention of mother-to-child HIV transmission (PMTCT) programs: 6.6%, 2005--2007; 9.5%, 2008--2009; 12.6%, 2010--2011. WHO stage IV at enrolment declined: 27.1%, 2005--2007; 20.2%, 2008--2009; 11.1% 2010--2011. Of the 42.5% and 29.5% with CD4+ data at enrolment and ART initiation respectively, median CD4+ count increased: 210cells/muL, 2005--2007; 262cells/muL, 2008--2009; 266cells/muL 2010--2011; but median CD4+ at ART initiation did not change (148cells/muL overall). Stavudine initiation declined: 84.9%, 2005--2007; 43.1%, 2008--2009; 19.7%, 2010--2011.Among children, median age (years) at enrolment decreased from 6.1(IQR:2.7-10.0) in 2005--2007 to 4.8(IQR:1.9-8.6) in 2008--2009, and 4.1(IQR:1.5-8.1) in 2010--2011 and children <24 months increased from 18.5% to 26.1% and 31.5% respectively. Entry from PMTCT was 7.0%, 2005--2007; 10.7%, 2008--2009; 15.0%, 2010--2011. WHO stage IV at enrolment declined from 22.9%, 2005--2007, to 18.3%, 2008--2009 to 13.9%, 2010--2011. Proportion initiating stavudine was 39.8% 2005--2007; 39.5%, 2008--2009; 26.1%, 2010--2011. Median age at ART initiation also declined significantly. Over time, the proportion of pregnant women and of adults and children enrolled from PMTCT programs increased. There was a decline in adults and children with advanced HIV disease at enrolment and initiation of stavudine. Pediatric age at enrolment and ART initiation declined. Results suggest HIV program maturation from an emergency response

Imaging Electronic Correlations in Twisted Bilayer Graphene near the Magic Angle

Twisted bilayer graphene with a twist angle of around 1.1{\deg} features a pair of isolated flat electronic bands and forms a strongly correlated electronic platform. Here, we use scanning tunneling microscopy to probe local properties of highly tunable twisted bilayer graphene devices and show that the flat bands strongly deform when aligned with the Fermi level. At half filling of the bands, we observe the development of gaps originating from correlated insulating states. Near charge neutrality, we find a previously unidentified correlated regime featuring a substantially enhanced flat band splitting that we describe within a microscopic model predicting a strong tendency towards nematic ordering. Our results provide insights into symmetry breaking correlation effects and highlight the importance of electronic interactions for all filling factors in twisted bilayer graphene.Comment: Main text 9 pages, 4 figures; Supplementary Information 25 page

Infective endocarditis caused by methicillin-resistant Staphylococcus aureus in a young woman after ear piercing: a case report

<p>Abstract</p> <p>Introduction</p> <p>Ear piercing is a common practice among Korean adolescents and young women and usually is performed by nonmedical personnel, sometimes under suboptimal hygienic conditions. Consequently, ear piercing has been associated with various infectious complications, including fatal infective endocarditis. We report a case of infective endocarditis that was caused by community-associated methicillin-resistant <it>Staphylococcus aureus </it>after ear piercing and that was accompanied by a noticeable facial rash.</p> <p>Case presentation</p> <p>A 29-year-old Korean woman underwent ear piercing six days before hospitalization. On admission, she had fever, erythematous maculopapular rashes on her face, signs of generalized emboli, vegetation in her mitral valve, and methicillin-resistant <it>S. aureus </it>bacteremia. On the basis of the blood culture results, she was treated with vancomycin in combination with gentamicin. On day six of hospitalization, a rupture of the papillary muscle of her mitral valve developed, and emergency cardiac surgery replacing her mitral valve with a prosthetic valve was performed. After eight weeks of antibiotic therapy, she was treated successfully and discharged without significant sequelae.</p> <p>Conclusions</p> <p>Numerable cases of body piercing-related infective endocarditis have been reported, and since ear piercing is commonplace nowadays, the importance of risk recognition cannot be overemphasized. In our report, a patient developed infective endocarditis that was caused by methicillin-resistant <it>S. aureus </it>after ear piercing and that was accompanied by an interesting feature, namely facial rash.</p

Rapamycin-loaded nanoparticles for inhibition of neointimal hyperplasia in experimental vein grafts

<p>Abstract</p> <p>Background</p> <p>Nanoparticles possess several advantages as a carrier system for intracellular delivery of therapeutic agents. Rapamycin is an immunosuppressive agent which also exhibits marked antiproliferative properties. We investigated whether rapamycin-loaded nanoparticles(NPs) can reduce neointima formation in a rat model of vein graft disease.</p> <p>Methods</p> <p>Poly(lactic-co-glycolic acid) (PLGA) NPs containing rapamycin was prepared using an oil/water solvent evaporation technique. Nanoparticle size and morphology were determined by dynamic light scattering methodology and electron microscopy. In vitro cytotoxicity of blank, rapamycin-loaded PLGA (RPLGA) NPs was studied using MTT Assay. Excised rat jugular vein was treated ex vivo with blank-NPs, or rapamycin-loaded NPs, then interposed back into the carotid artery position using a cuff technique. Grafts were harvested at 21 days and underwent morphometric analysis as well as immunohistochemical analysis.</p> <p>Results</p> <p>Rapamycin was efficiently loaded in PLGA nanoparticles with an encapsulation efficiency was 87.6%. The average diameter of NPs was 180.3 nm. The NPs-containing rapamycin at 1 ng/ml significantly inhibited vascular smooth muscular cells proliferation. Measurement of rapamycin levels in vein grafts shown that the concentration of rapamycin in vein grafts at 3 weeks after grafting were 0.9 ± 0.1 μg/g. In grafted veins without treatment intima-media thickness was 300.4 ±181.5 μm after grafting 21 days. Whereas, Veins treated with rapamycin-loaded NPs showed a reduction of intimal-media thickness of 150.2 ± 62.5 μm (p = 0.001). CD-31 staining was used to measure luminal endothelial coverage in grafts and indicated a high level of endothelialization in 21 days vein grafts with no significant effect of blank or rapamycin-loaded NPs group.</p> <p>Conclusions</p> <p>We conclude that sustained-release rapamycin from rapymycin loaded NPs inhibits vein graft thickening without affecting the reendothelialization in rat carotid vein-to-artery interposition grafts and this may be a promising therapy for the treatment of vein graft disease.</p

Hepatitis B and Hepatocellular Carcinoma Screening Among Asian Americans: Survey of Safety Net Healthcare Providers

BackgroundPhysician patterns of screening for hepatitis B (HBV) and hepatocellular carcinoma (HCC) among Asian Americans are not well described.AimsTo describe HBV and HCC screening practices among providers with large Asian American populations.MethodsProviders within San Francisco's safety net system were surveyed with respect to HBV and HCC screening practices as well as knowledge, attitudes, and barriers to HCC screening.ResultsAmong the 109 respondents (response rate = 72%), 62% were aged &gt;40, 65% female, 24% Asian, 87% primary care providers, and 48% had &gt;25% Asian patients. Only 76% had screened &gt;50% of their Asian patients for HBV and 43% had vaccinated &gt;50% of eligible patients against HBV. Although 94% knew Asians were disproportionately affected by HCC, only 79% had screened for HCC in &gt;50% of their Asian patients with chronic hepatitis B (CHB). A majority believed that HCC screening in CHB reduces HCC mortality (70%) and is cost-effective (57%). The most common HCC screening modality was AFP with abdominal ultrasound every 6-12 months (63%). Factors associated with HBV screening were familiarity with AASLD guidelines (OR 6.4, 95% CI 1.3-30.1, p = 0.02) and having vaccinated &gt;50% of eligible patients against HBV (OR 2.2, 95% CI 1.1-4.5, p = 0.03). Factors associated with HCC screening using abdominal ultrasound every 6-12 months were having &gt;25% Asian patients (OR = 4.5, 95% CI 1.3-15.3, p = 0.02) and higher HCC knowledge score (OR = 1.9 per item, 95% CI 1.01-3.6, p = 0.045).ConclusionsHBV and HCC screening rates and HBV vaccination among Asians from physician report is suboptimal. HCC screening is associated with having more Asian patients and higher provider knowledge. Provider education is essential in increasing rates of HBV and HCC screening among Asian Americans