Digesting Digestion: An Educational Laboratory to Teach Students about Enzymes and the Gastrointestinal Tract.

Digestion is a fundamentally important process for an individual's life. However, the physical process of digestion is hidden inside the body, making it challenging to understand and a particularly difficult topic for students to learn in the classroom. Traditional approaches to teaching body processes include a mixture of textbook teaching and visual learning. However, digestion is not particularly visual. This activity is designed to engage students using a combination of visual, inquiry-based, and experiential learning approaches and introduces the scientific method to students in secondary school. The laboratory simulates digestion, creating a "stomach" inside of a clear vial. Students fill the vials with a protease solution and visually observe the digestion of food. By making predictions about the types of biomolecules that will be digested, students begin to learn and understand basic biochemistry in a relatable context, while simultaneously understanding anatomical and physiological concepts. We trialled this activity at two schools, where we received positive feedback from teachers and students, indicating that the practical enhanced student understanding of the digestion process. We see this lab as a valuable learning activity that can be extended broadly across multiple classrooms around the world.

Gold-Cage Perovskites: A Three-Dimensional AuIII-X Framework Encasing Isolated MX63- Octahedra (MIII = In, Sb, Bi; X = Cl-, Br-, I-).

The Cs8AuIII4MIIIX23 (M = In3+, Sb3+, Bi3+; X = Cl-, Br-, I-) perovskites are composed of corner-sharing Au-X octahedra that trace the edges of a cube containing an isolated M-X octahedron at its body center. This structure, unique within the halide perovskite family, may be derived from the doubled cubic perovskite unit cell by removing the metals at the cube faces. To our knowledge, these are the only halide perovskites where the octahedral sites do not bear an average 2+ charge. Charge compensation in these materials requires a stoichiometric halide vacancy, which is disordered around the Au atom at the unit-cell corner and orders when the crystallization is slowed. Using X-ray crystallography, X-ray absorption spectroscopy, and pair distribution function analysis, we elucidate the structure of this unusual perovskite. Metal-site alloying produces further intricacies in this structure, which our model explains. Compared to other halide perovskites, this class of materials shows unusually low absorption onset energies ranging between ca. 1.0 and 2.4 eV. Partial reduction of Au3+ to Au+ affords an intervalence charge-transfer band, which redshifts the absorption onset of Cs8Au4InCl23 from 2.4 to 1.5 eV. With connected Au-X octahedra and isolated M-X octahedra, this structure type combines zero- and three-dimensional metal-halide sublattices in a single material and stands out among halide perovskites for its ordering of homovalent metals, ordering of halide vacancies, and incorporation of purely trivalent metals at the octahedral sites.

Experiences of HIV/STD Providers in New York State During Hurricane Sandy: Strengths, Challenges, and Recommendations.

OBJECTIVES: The aim of this study was to assess strengths and challenges experienced by HIV/STD providers in providing care during the response to Hurricane Sandy (Sandy) in New York State, and their recommendations for future preparedness. METHODS: A mixed methods approach, including a focus group (n = 3), interviews (n = 3), and survey (n = 31) of HIV/STD providers, was used. Key words identified by means of open coding methodology from collected data were organized into strengths, challenges, and recommendations and then grouped into federal and study-associated preparedness capabilities. RESULTS: Key words were organized into 81 strengths (38.8%), 73 challenges (34.9%), and 55 recommendations (26.3%). Services most interrupted during Sandy were related to HIV/STD outreach and education. While providers reported challenges with external agency communication, the ability to still connect clients to needed resources was reported as a strength. Strengthening partnerships with federal, state, and local agencies was among the major recommendations made by these providers. CONCLUSIONS: This study presents unique information about challenges experienced by HIV/STD providers in providing services during a natural disaster and the use of national public health emergency preparedness capabilities to address and overcome those challenges. Lessons learned and recommendations regarding inter-agency communications emerged as an important priority during a natural disaster to minimize or reduce service interruption.

An automatically curated first-principles database of ferroelectrics.

Ferroelectric materials have technological applications in information storage and electronic devices. The ferroelectric polar phase can be controlled with external fields, chemical substitution and size-effects in bulk and ultrathin film form, providing a platform for future technologies and for exploratory research. In this work, we integrate spin-polarized density functional theory (DFT) calculations, crystal structure databases, symmetry tools, workflow software, and a custom analysis toolkit to build a library of known, previously-proposed, and newly-proposed ferroelectric materials. With our automated workflow, we screen over 67,000 candidate materials from the Materials Project database to generate a dataset of 255 ferroelectric candidates, and propose 126 new ferroelectric materials. We benchmark our results against experimental data and previous first-principles results. The data provided includes atomic structures, output files, and DFT values of band gaps, energies, and the spontaneous polarization for each ferroelectric candidate. We contribute our workflow and analysis code to the open-source python packages atomate and pymatgen so others can conduct analogous symmetry driven searches for ferroelectrics and related phenomena.

High Compression-Induced Conductivity in a Layered Cu-Br Perovskite.

We show that the onset pressure for appreciable conductivity in layered copper-halide perovskites can decrease by ca. 50 GPa upon replacement of Cl with Br. Layered Cu-Cl perovskites require pressures >50 GPa to show a conductivity of 10-4  S cm-1 , whereas here a Cu-Br congener, (EA)2 CuBr4 (EA=ethylammonium), exhibits conductivity as high as 2×10-3  S cm-1 at only 2.6 GPa, and 0.17 S cm-1 at 59 GPa. Substitution of higher-energy Br 4p for Cl 3p orbitals lowers the charge-transfer band gap of the perovskite by 0.9 eV. This 1.7 eV band gap decreases to 0.3 eV at 65 GPa. High-pressure X-ray diffraction, optical absorption, and transport measurements, and density functional theory calculations allow us to track compression-induced structural and electronic changes. The notable enhancement of the Br perovskite's electronic response to pressure may be attributed to more diffuse Br valence orbitals relative to Cl orbitals. This work brings the compression-induced conductivity of Cu-halide perovskites to more technologically accessible pressures.

Capturing the Mechanism Underlying TOP mRNA Binding to LARP1.

The RNA-binding protein La-related protein 1 (LARP1) plays a central role in ribosome biosynthesis. Its C-terminal DM15 region binds the 7-methylguanosine (m7G) cap and 5' terminal oligopyrimidine (TOP) motif characteristic of transcripts encoding ribosomal proteins and translation factors. Under the control of mammalian target of rapamycin complex 1 (mTORC1), LARP1 regulates translation of these transcripts. Characterizing the dynamics of DM15-TOP recognition is essential to understanding this fundamental biological process. We use molecular dynamics simulations, biophysical assays, and X-ray crystallography to reveal the mechanism of DM15 binding to TOP transcripts. Residues C-terminal to the m7G-binding site play important roles in cap recognition. Furthermore, we show that the unusually static pocket that recognizes the +1 cytosine characteristic of TOP transcripts drives binding specificity. Finally, we demonstrate that the DM15 pockets involved in TOP-specific m7GpppC-motif recognition are likely druggable. Collectively, these studies suggest unique opportunities for further pharmacological development.

Emergence of topological electronic phases in elemental lithium under pressure.

Lithium, a prototypical simple metal under ambient conditions, has a surprisingly rich phase diagram under pressure, taking up several structures with reduced symmetry, low coordination numbers, and even semiconducting character with increasing density. Using first-principles calculations, we demonstrate that some predicted high-pressure phases of elemental Li also host topological electronic structures. Beginning at 80 GPa and coincident with a transition to the previously predicted Pbca phase, we find Li to be a Dirac nodal line semimetal. We further calculate that Li retains linearly dispersing energy bands near the Fermi energy in subsequent predicted higher-pressure phases and that it exhibits a Lifshitz transition between two Cmca phases at 220 GPa. The Fd[Formula: see text]m phase at 500 GPa forms buckled honeycomb layers that give rise to a Dirac crossing 1 eV below the Fermi energy. The well-isolated topological nodes near the Fermi level in these phases result from increasing p-orbital character with density at the Fermi level, itself a consequence of rising 1s core wavefunction overlap, and a preference for nonsymmorphic symmetries in the crystal structures favored at these pressures. Our results provide evidence that under pressure, bulk 3D materials with light elements, or even pure elemental systems, can undergo phase transitions hosting nontrivial topological phase transitions hosting nontrivial topological properties near the Fermi level with measurable consequences and that, through pressure, we can access these phases in elemental lithium.

Tuning the bandgap of Cs2AgBiBr6 through dilute tin alloying.

The promise of lead halide hybrid perovskites for optoelectronic applications makes finding less-toxic alternatives a priority. The double perovskite Cs2AgBiBr6 (1) represents one such alternative, offering long carrier lifetimes and greater stability under ambient conditions. However, the large and indirect 1.95 eV bandgap hinders its potential as a solar absorber. Here we report that alloying crystals of 1 with up to 1 atom% Sn results in a bandgap reduction of up to ca. 0.5 eV while maintaining low toxicity. Crystals can be alloyed with up to 1 atom% Sn and the predominant substitution pathway appears to be a ∼2 : 1 substitution of Sn2+ and Sn4+ for Ag+ and Bi3+, respectively, with Ag+ vacancies providing charge compensation. Spincoated films of 1 accommodate a higher Sn loading, up to 4 atom% Sn, where we see mostly Sn2+ substitution for both Ag+ and Bi3+. Density functional theory (DFT) calculations ascribe the bandgap redshift to the introduction of Sn impurity bands below the conduction band minimum of the host lattice. Using optical absorption spectroscopy, photothermal deflection spectroscopy, X-ray absorption spectroscopy, 119Sn NMR, redox titration, single-crystal and powder X-ray diffraction, multiple elemental analysis and imaging techniques, and DFT calculations, we provide a detailed analysis of the Sn content and oxidation state, dominant substitution sites, and charge-compensating defects in Sn-alloyed Cs2AgBiBr6 (1:Sn) crystals and films. An understanding of heterovalent alloying in halide double perovskites opens the door to a wider breadth of potential alloying agents for manipulating their band structures in a predictable manner.

Superstorm Sandy's impact on the provision of WIC (Special Supplemental Nutrition Program for Women, Infants, and Children) services in New York State.

OBJECTIVE: Services provided by the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) were interrupted in 2012 when Superstorm Sandy struck New York State (NYS). The present study evaluates the impact on WIC providers. DESIGN: A focus group, telephone interviews and anonymous online survey were conducted. Qualitative data were analysed by coding transcribed text into key words and identifying major and minor themes for strengths, challenges and recommendations using national public health preparedness capabilities. Survey responses were analysed quantitatively; reported challenges were classified by preparedness capability. SETTING: The focus group was held at a 2014 regional WIC meeting. Interviews and a survey were conducted via telephone in 2014 and online in 2015, respectively. SUBJECTS: WIC staff representing New York City and three NYS counties. RESULTS: In the focus group (n 12) and interviews (n 6), 'emergency operations coordination' was the most cited capability as a strength, 'environmental health protection' (against environmental hazards) as a challenge and 'flexibility' (on rules and procedures) as a recommendation. In the survey (n 24), the capability 'information sharing' was most often cited as a challenge. Most staff (66·6 %) reported their programmes were at least somewhat prepared for future weather-related disasters. Only 16·7 % indicated having practiced a work-related emergency response plan since Sandy. Staff who practiced an emergency response plan were more likely to indicate they were prepared (P < 0·05). CONCLUSIONS: The study identified WIC programme areas requiring preparedness improvements. The research methodology can be utilized to assess the continuity of other public health services during disasters.

Superstorm Sandy: Emergency management staff perceptions of impact and recommendations for future preparedness, New York State.

OBJECTIVE: This study collected and summarized feedback from staff at the New York State (NYS) Office of Emergency Management (OEM) and three county OEMs within NYS to understand lessons learned from the 2012 Superstorm Sandy. DESIGN: Cross-sectional qualitative and quantitative analysis. SUBJECTS, PARTICIPANTS: One staff person from each identified critical role from the state and county OEMs who were still employed in the roles identified. INTERVENTIONS: In-person interviews in 2014 followed by an anonymous survey in 2015 examined the response strengths, challenges, and recommendations using federally and study-defined Public Health Preparedness Capabilities. Quantitative analysis of staff survey ratings was used to summarize perceptions of interagency collaboration, communication effectiveness, and differences by staff position. RESULTS: Response rates were 78 percent for interviews (n = 7) and 45 percent for surveys (n = 36). In interviews, "emergency operations coordination" was cited most frequently (48 percent), specifically for successful interagency coordination. "Emergency operations coordination" was also cited most among challenges (45 percent), with emphasis on problems with uniformity of software systems across agencies. Survey responses indicated that "volunteer management" (50 percent) and the "safety and health of responders" (40 percent) were frequently reported as challenges. Additionally, 38 percent of OEM staff reported that situation reports submitted by health departments need improvement. Recommendations from OEM staff included "emergency operations coordination" (36 percent) such as sharing of resources and "training" (16 percent) including hospital evacuation training. CONCLUSIONS: Analysis of OEM staff feedback identified specific challenges, and concrete recommendations were made to improve response going forward.

Automated Synthesis of Well-Defined Polymers and Biohybrids by Atom Transfer Radical Polymerization Using a DNA Synthesizer.

A DNA synthesizer was successfully employed for preparation of well-defined polymers by atom transfer radical polymerization (ATRP), in a technique termed AutoATRP. This method provides well-defined homopolymers, diblock copolymers, and biohybrids under automated photomediated ATRP conditions. PhotoATRP was selected over other ATRP methods because of mild reaction conditions, ambient temperature, tolerance to oxygen, and no need to introduce reducing agents or radical initiators. Both acrylate and methacrylate monomers were successfully polymerized with excellent control in the DNA synthesizer. Diblock copolymers were synthesized with different targeted degrees of polymerization and with high retention of chain-end functionality. Both hydrophobic and hydrophilic monomers were grafted from DNA. The DNA-polymer hybrids were characterized by SEC and DLS. The AutoATRP method provides an efficient route to prepare a range of different polymeric materials, especially polymer-biohybrids.

Pseudo-Ligandless Click Chemistry for Oligonucleotide Conjugation.

Particularly for its use in bioconjugations, the copper-catalyzed (or copper-promoted) azide-alkyne cycloaddition (CuAAC) reaction or 'click chemistry', has become an essential component of the modern chemical biologist's toolbox. Click chemistry has been applied to DNA, and more recently, RNA conjugations, and the protocols presented here can be used for either. The reaction can be carried out in aqueous buffer, and uses acetonitrile as a minor co-solvent that serves as a ligand to stabilize the copper. The method also includes details on the analysis of the reaction product. © 2016 by John Wiley & Sons, Inc.

New York State Public Health System Response to Hurricane Sandy: Lessons From the Field.

OBJECTIVE: The aim of this study was to conduct interviews with public health staff who responded to Hurricane Sandy and to analyze their feedback to assess response strengths and challenges and recommend improvements for future disaster preparedness and response. METHODS: Qualitative analysis was conducted of information from individual confidential interviews with 35 staff from 3 local health departments in New York State (NYS) impacted by Hurricane Sandy and the NYS Department of Health. Staff were asked about their experiences during Hurricane Sandy and their recommendations for improvements. Open coding was used to analyze interview transcripts for reoccurring themes, which were labeled as strengths, challenges, or recommendations and then categorized into public health preparedness capabilities. RESULTS: The most commonly cited strengths, challenges, and recommendations related to the Hurricane Sandy public health response in NYS were within the emergency operations coordination preparedness capability, which includes the abilities of health department staff to partner among government agencies, coordinate with emergency operation centers, conduct routine conference calls with partners, and manage resources. CONCLUSIONS: Health departments should ensure that emergency planning includes protocols to coordinate backup staffing, delineation of services that can be halted during disasters, clear guidelines to coordinate resources across agencies, and training for transitioning into unfamiliar disaster response roles. (Disaster Med Public Health Preparedness. 2016;10:443-453).

New York State Public Health System Response to Hurricane Sandy: An Analysis of Survey Feedback.

OBJECTIVE: The objective was to provide a broad spectrum of New York State and local public health staff the opportunity to contribute anonymous feedback on their own and their agencies' preparedness and response to Hurricane Sandy, perceived challenges, and recommendations for preparedness improvement. METHODS: In 2015, 2 years after Hurricane Sandy, public health staff who worked on Hurricane Sandy response were identified and were provided a link to the anonymous survey. Quantitative analyses were used for survey ratings and qualitative content analyses were used for open-ended questions. RESULTS: Surveys were completed by 129 local health department (LHD) staff in 3 counties heavily impacted by Sandy (Nassau, Suffolk, and Westchester) and 69 staff in the New York State Department of Health who supported the LHDs. Staff agreed that their Hurricane Sandy responsibilities were clearly defined and that they had access to adequate information to perform their jobs. Challenges were reported in the operational, communication, service interruptions, and staff categories, with LHD staff also reporting challenges with shelters. CONCLUSIONS: New York local and state public health staff indicated that they were prepared for Hurricane Sandy. However, their feedback identified specific challenges and recommendations that can be addressed to implement improved preparedness and response strategies. (Disaster Med Public Health Preparedness. 2016;10:454-462).

New York State Public Health System Response to Hurricane Sandy: An Analysis of Emergency Reports.

OBJECTIVE: Analyzing Hurricane Sandy emergency reports to assess the New York State (NYS) public health system response will help inform and improve future disaster preparedness and response. METHODS: Qualitative analysis of NYS Department of Health (NYSDOH) and Nassau and Suffolk County local health department (LHD) emergency reports was conducted. Three after-action reports and 48 situation reports were reviewed, grouped by key words and sorted into 16 Public Health Preparedness Capabilities. Within each capability, key words were labeled as strengths, challenges, or recommendations. RESULTS: The NYSDOH capability most cited as a strength was successful emergency operations coordination, eg, interagency conference calls (27.4% of 1681 strengths). The most cited challenge was environmental health protection, eg, mold and oil spills (28% of 706 challenges). The LHD capability most cited both as a strength (46.7% of 30 strengths) and as a challenge (32.5% of 123 challenges) was emergency operations coordination. Strengths were exemplified by sharing local resources and challenges by insufficient memorandums of understanding for coordination. CONCLUSIONS: Post-disaster emergency reports should be systematically reviewed to highlight both successes and areas for improvement. Future studies should prioritize collecting feedback from a wider spectrum of public health and service provider staff for planning of preparedness and response activities. (Disaster Med Public Health Preparedness. 2015;10:308-313).