Showing papers by "California State University, Long Beach published in 2018"

Metal-Organic Frameworks for Separation.

Abstract: Separation is an important industrial step with critical roles in the chemical, petrochemical, pharmaceutical, and nuclear industries, as well as in many other fields. Although much progress has been made, the development of better separation technologies, especially through the discovery of high-performance separation materials, continues to attract increasing interest due to concerns over factors such as efficiency, health and environmental impacts, and the cost of existing methods. Metal-organic frameworks (MOFs), a rapidly expanding family of crystalline porous materials, have shown great promise to address various separation challenges due to their well-defined pore size and unprecedented tunability in both composition and pore geometry. In the past decade, extensive research is performed on applications of MOF materials, including separation and capture of many gases and vapors, and liquid-phase separation involving both liquid mixtures and solutions. MOFs also bring new opportunities in enantioselective separation and are amenable to morphological control such as fabrication of membranes for enhanced separation outcomes. Here, some of the latest progress in the applications of MOFs for several key separation issues, with emphasis on newly synthesized MOF materials and the impact of their compositional and structural features on separation properties, are reviewed and highlighted.

Pain and Depression: A Systematic Review.

Abstract: Background Pain comorbid with depression is frequently encountered in clinical settings and often leads to significant impaired functioning. Given the complexity of comorbidities, it is important to address both pain and depressive symptoms when evaluating treatment options. Aim To review studies addressing pain comorbid with depression, and to report the impact of current treatments. Method A systematic search of the literature databases was conducted according to predefined criteria. Two authors independently conducted a focused analysis of the full-text articles and reached a consensus on 28 articles to be included in this review. Results Overall, studies suggested that pain and depression are highly intertwined and may co-exacerbate physical and psychological symptoms. These symptoms could lead to poor physical functional outcomes and longer duration of symptoms. An important biochemical basis for pain and depression focuses on serotonergic and norepinephrine systems, which is evident in the pain-ameliorating properties of serotonergic and norepinephrine antidepressants. Alternative pharmacotherapies such as ketamine and cannabinoids appear to be safe and effective options for improving depressive symptoms and ameliorating pain. In addition, cognitive-behavioral therapy may be a promising tool in the management of chronic pain and depression. Conclusion The majority of the literature indicates that patients with pain and depression experience reduced physical, mental, and social functioning as opposed to patients with only depression or only pain. In addition, ketamine, psychotropic, and cognitive-behavioral therapies present promising options for treating both pain and depression.

Mobilizing Community Health Workers to Address Mental Health Disparities for Underserved Populations: A Systematic Review.

Abstract: This systematic review evaluates efforts to date to involve community health workers (CHWs) in delivering evidence-based mental health interventions to underserved communities in the United States and in low- and middle-income countries. Forty-three articles (39 trials) were reviewed to characterize the background characteristics of CHW, their role in intervention delivery, the types of interventions they delivered, and the implementation supports they received. The majority of trials found that CHW-delivered interventions led to symptom reduction. Training CHWs to support the delivery of evidence-based practices may help to address mental health disparities. Areas for future research as well as clinical and policy implications are discussed.

Articular cartilage: injury pathways and treatment options.

Abstract: Articular cartilage injury and degeneration is a frequent occurrence in synovial joints. Treatment of these articular cartilage lesions are a challenge because this tissue is incapable of quality repair and/or regeneration to its native state. Nonoperative treatments endeavor to control symptoms, and include anti-inflammatory medication, viscosupplementation, bracing, orthotics, and activity modification. Techniques to stimulate the intrinsic repair (fibrocartilage) process include drilling, abrasion, and microfracture of the subchondral bone. Currently, the clinical biologic approaches to treat cartilage defects include autologous chondrocyte implantation, periosteal transfer, and osteochondral autograft or allograft transplantation. Newer strategies employing tissue engineering being studied involve the use of combinations of progenitor cells, bioactive factors, and matrices, and the use of focal synthetic devices. Many new and innovative treatments are being explored in this exciting field. However, there is a paucity of prospective, randomized controlled clinical trials that have compared the various techniques, treatment options, indications and efficacy.

Safety and Tolerability of Multiple Ascending Doses of PRX002/RG7935, an Anti–α-Synuclein Monoclonal Antibody, in Patients With Parkinson Disease: A Randomized Clinical Trial

Abstract: Importance Aggregated α-synuclein is believed to be central to the pathogenesis of Parkinson disease (PD). PRX002/RG7935 (PRX002) is a humanized monoclonal antibody designed to target aggregated forms of α-synuclein, thereby inhibiting neuron-to-neuron transfer of presumed pathogenic forms of α-synuclein, potentially resulting in neuronal protection and slowing disease progression. Objective To evaluate the safety and tolerability of multiple intravenous infusions of PRX002 in patients with idiopathic PD. Design, Setting, and Participants Multicenter, randomized, double-blind, placebo-controlled, multiple ascending-dose trial at 8 US study centers from July 2014 to September 2016. Eligible participants were aged 40 to 80 years with mild to moderate idiopathic PD (Hoehn and Yahr stages 1-3). Interventions Participants were enrolled into 6 ascending-dose cohorts and randomly assigned to receive PRX002 (0.3 mg/kg, 1.0 mg/kg, 3.0 mg/kg, 10 mg/kg, 30 mg/kg, or 60 mg/kg) or placebo. Participants received 3 intravenous infusions every 4 weeks of PRX002 or placebo and were monitored during a 24-week observational period. Main Outcomes and Measures Safety and tolerability assessments included physical and neurological examinations, laboratory tests, vital signs, and adverse events. Pharmacokinetic parameters included maximum PRX002 concentration, area under the curve, and half-life. Results Of the 80 participants, most were white (97.5%; n = 78) and male (80%; n = 64); median (SD) age was 58 (8.4) years. PRX002 was generally safe and well tolerated; no serious or severe PRX002-related treatment-emergent adverse events (TEAEs) were reported. The TEAEs experienced by at least 5% of patients receiving PRX002, irrespective of relatedness to study drug, were constipation (9.1%; n = 5), infusion reaction (7.3%; n = 4), diarrhea (5.5%; n = 3), headache (5.5%; n = 3), peripheral edema (5.5%; n = 3), post–lumbar puncture syndrome (5.5%; n = 3), and upper respiratory tract infection (5.5%; n = 3). No antidrug antibodies were detected. Serum PRX002 levels increased in an approximately dose-proportional manner; mean terminal elimination half-life was similar across all doses (10.2 days). Rapid dose- and time-dependent mean reductions from baseline vs placebo in free serum α-synuclein levels of up to 97% were seen after a single infusion at the highest dose (F78,284= 1.66;P = .002), with similar reductions after 2 additional infusions. Mean cerebrospinal fluid PRX002 concentration increased with PRX002 dose and was approximately 0.3% relative to serum across all dose cohorts. Conclusions and Relevance Single and multiple doses of PRX002 were generally safe and well tolerated and resulted in robust binding of peripheral α-synuclein and dose-dependent increases of PRX002 in cerebrospinal fluid, reaching cerebrospinal fluid concentrations that may be expected to engage extracellular aggregated α-synuclein in the brain. Findings support the design of an ongoing phase 2 clinical study (NCT03100149). Trial Registration ClinicalTrials.gov Identifier:NCT02157714

In situ synthesis of n–n Bi2MoO6 & Bi2S3 heterojunctions for highly efficient photocatalytic removal of Cr(VI)

Abstract: Exploiting novel photocatalysts with high efficiency and durability for reduction of hexavalent chromium (Cr(VI)) has gained attention from fundamental science and industrial research. In this work, we synthesized novel two-dimensional (2D) n–n Bi2MoO6 & Bi2S3 heterojunctions by a facile in situ anion exchange process for remarkably efficient removal of Cr(VI). Results show that Bi2MoO6 & Bi2S3 heterojunctions with core–shell structures are formed through the intimate contact of Bi2MoO6 core and Bi2S3 shell. The prepared Bi2MoO6 & Bi2S3 heterojunctions exhibit unprecedented photocatalytic activity for reduction of Cr(VI) under visible light irradiation. The optimized BMO-S1 heterojunction displays the highest reduction efficiency (κapp = 0.164 min−1) for Cr(VI) reduction. To the best of our knowledge, it is one of the highest reduction rate achieved among reported photocatalysts for Cr(VI) reduction under visible-light irradiation. Detailed studies show that strong selective adsorption for Cr(VI) enhances this unprecedented photocatalytic activity. Moreover, the intimate heterojunction between Bi2MoO6 core and Bi2S3 shell can efficiently deteriorate the charge carrier recombination and Bi2S3 content can boost visible light harvesting, thereby contributing to the remarkable photocatalytic catalytic activity, which were proven by PL, EIS and transient photocurrent responses. Characterization of Mott–Schottky plots and DRS prove that the Bi2MoO6 & Bi2S3 heterojunctions established a type-II band alignment with intimate contact, accounting for the efficient transfer and separation of photogenerated carriers. This work provides a simple route for facial synthesis of heterojunction photocatalysts for Cr(VI) reduction in industrial applications.

A Qualitative Exploration of Perceptions of Algorithmic Fairness

Abstract: Algorithmic systems increasingly shape information people are exposed to as well as influence decisions about employment, finances, and other opportunities. In some cases, algorithmic systems may be more or less favorable to certain groups or individuals, sparking substantial discussion of algorithmic fairness in public policy circles, academia, and the press. We broaden this discussion by exploring how members of potentially affected communities feel about algorithmic fairness. We conducted workshops and interviews with 44 participants from several populations traditionally marginalized by categories of race or class in the United States. While the concept of algorithmic fairness was largely unfamiliar, learning about algorithmic (un)fairness elicited negative feelings that connect to current national discussions about racial injustice and economic inequality. In addition to their concerns about potential harms to themselves and society, participants also indicated that algorithmic fairness (or lack thereof) could substantially affect their trust in a company or product.

Acid and Base Resistant Zirconium Polyphenolate-Metalloporphyrin Scaffolds for Efficient CO2 Photoreduction.

Abstract: A series of zirconium polyphenolate-decorated-(metallo)porphyrin metal-organic frameworks (MOFs), ZrPP-n (n = 1, 2), featuring infinite ZrIV -oxo chains linked via polyphenolate groups on four peripheries of eclipse-arranged porphyrin macrocycles, are successfully constructed through a top-down process from simulation to synthesis. These are the unusual examples of Zr-MOFs (or MOFs in general) based on phenolic porphyrins, instead of commonly known carboxylate-based types. Representative ZrPP-1 not only exhibits strong acid resistance (pH = 1, HCl) but also remains intact even when immersed in saturated NaOH solution (≈20 m), an exceptionally large range of pH resistance among MOFs. The metallation at the porphyrin core gives rise to materials with enhanced sorption and catalytic properties. In particular, ZrPP-1-Co, with precise and uniform distribution of active centers, exhibits not only high CO2 trapping capability (≈90 cm3 g-1 at 1 atm, 273 K, among the highest in Zr-MOFs) but also high photocatalytic activity for reduction of CO2 into CO (≈14 mmol g-1 h-1 ) and high selectivity over CH4 (>96.4%) without any cocatalyst under visible-light irradiation (λ > 420 nm). Given the strong chemical resistance under extreme alkali conditions, these catalysts can be recycled without appreciable loss of activity. The possible mechanism for photocatalytic reduction of CO2 -to-CO over ZrPP-1-Co is also proposed.

Developing a STEM Identity Among Young Women: A Social Identity Perspective:

Abstract: We conducted a systematic review of empirical research focused on the experiences of female students in science, technology, engineering, and mathematics (STEM) during middle and high school. Drawing on social identity theory, recent research was synthesized to explore how aspects of the social environment influence STEM identity development. Findings indicate that young women experience challenges to their participation and inclusion when they are in STEM settings. Additionally, we found that perceptions regarding who is part of the ingroup or outgroup of STEM fields can be changed through intervention and educational programs. We conclude with recommendations for theory, research, programs, and policy for STEM identity development among young women, informed by a social identity perspective.

Non-Invasive Activation of Cervical Spinal Networks after Severe Paralysis

Abstract: Paralysis of the upper extremities following cervical spinal cord injury (SCI) significantly impairs one's ability to live independently. While regaining hand function or grasping ability ...

Tunable MoS2/SnO2 P–N Heterojunctions for an Efficient Trimethylamine Gas Sensor and 4-Nitrophenol Reduction Catalyst

Abstract: Synthetic design and construction of P–N heterojunctions are attracting increasing attention due to their potential applications such as in catalysis, gas sensors, and energy storage and conversion...

Deep Linear Networks with Arbitrary Loss: All Local Minima Are Global

Abstract: We consider deep linear networks with arbitrary convex differentiable loss. We provide a short and elementary proof of the fact that all local minima are global minima if the hidden layers are either 1) at least as wide as the input layer, or 2) at least as wide as the output layer. This result is the strongest possible in the following sense: If the loss is convex and Lipschitz but not differentiable then deep linear networks can have sub-optimal local minima.

Students’ perceptions of STEM learning after participating in a summer informal learning experience

Abstract: Informal learning environments increase students’ interest in STEM (eg, Mohr‐Schroeder et al School Sci Math 114: 291–301, 2014) and increase the chances a student will pursue a STEM career (Kitchen et al Sci Educ 102: 529–547, 2018) The purpose of this study was to examine the impact of an informal STEM summer learning experience on student participants, to gain in-depth perspectives about how they felt this experience prepared them for their in-school mathematics and science classes as well as how it influenced their perception of STEM learning Students’ attitudes and perceptions toward STEM are affected by their motivation, experience, and self-efficacy (Brown et al J STEM Educ Innov Res 17: 27, 2016) The academic and social experiences students’ have are also important Traditionally, formal learning is taught in a solitary form (Martin Science Education 88: S71–S82, 2004), while, informal learning is brimming with chances to connect and intermingle with peers (Denson et al J STEM Educ: Innovations and Research 16: 11, 2015) We used a naturalistic inquiry, phenomenological approach to examine students’ perceptions of STEM while participating in a summer informal learning experience Data came from students at the summer informal STEM learning experiences at three diverse institutions across the USA Data were collected from reflection forms and interviews which were designed to explore students’ “lived experiences” (Van Manen 1990, p 9) and how those experiences influenced their STEM learning As we used a situative lens to examine the research question of how participation in an informal learning environment influences students’ perceptions of STEM learning, three prominent themes emerged from the data The informal learning environment (a) provided context and purpose to formal learning, (b) provided students opportunity and access, and (c) extended STEM content learning and student engagement By using authentic STEM workplaces, the STEM summer learning experience fostered a learning environment that extended and deepened STEM content learning while providing opportunity and access to content, settings, and materials that most middle level students otherwise would not have access to Students also acknowledged the access they received to hands-on activities in authentic STEM settings and the opportunities they received to interact with STEM professionals were important components of the summer informal learning experience

Quark deconfinement as a supernova explosion engine for massive blue supergiant stars

Abstract: Blue supergiant stars develop into core-collapse supernovae—one of the most energetic outbursts in the Universe—when all nuclear burning fuel is exhausted in the stellar core. Previous attempts have failed to explain observed explosions of such stars, which have a zero-age main-sequence mass of 50 M⊙ or more. Here, we exploit the largely uncertain state of matter at high density, and connect the modelling of such stellar explosions with a first-order phase transition from nuclear matter to the quark–gluon plasma. The resulting energetic supernova explosions can account for a large variety of light curves, from peculiar type II supernovae to superluminous events. The remnants are neutron stars with a quark matter core, known as hybrid stars, of about 2 M⊙ at birth. A Galactic event of this kind could be observable owing to the release of a second neutrino burst. Its observation would confirm such a first-order phase transition at densities relevant for astrophysics. Blue supergiant stars (BSGs) can undergo core collapse, resulting in a type II supernova explosion. Here, Tobias Fischer et al. identify a novel phase transition from nuclear matter to a quark–gluon plasma for particularly massive BSGs (>50 M☉) that explains their explosion.

UV Photolysis of Chloramine and Persulfate for 1,4-Dioxane Removal in Reverse-Osmosis Permeate for Potable Water Reuse

Abstract: A sequential combination of membrane treatment and UV-based advanced oxidation processes (UV/AOP) has become the industry standard for potable water reuse. Chloramines are used as membrane antifouling agents and therefore carried over into the UV/AOP. In addition, persulfate (S2O82-) is an emerging oxidant that can be added into a UV/AOP, thus creating radicals generated from both chloramines and persulfate for water treatment. This study investigated the simultaneous photolysis of S2O82- and monochloramine (NH2Cl) on the removal of 1,4-dioxane (1,4-D) for potable-water reuse. The dual oxidant effects of NH2Cl and S2O82- on 1,4-D degradation were examined at various levels of oxidant dosage, chloride, and solution pH. Results showed that a NH2Cl-to-S2O82- molar ratio of 0.1 was optimal, beyond which the scavenging by NH2Cl of HO•, SO4•-, and Cl2•- radicals decreased the 1,4-D degradation rate. At the optimal ratio, the degradation rate of 1,4-D increased linearly with the total oxidant dose up to 6 mM. The combined photolysis of NH2Cl and S2O82- was sensitive to the solution pH due to a disproportionation of NH2Cl at pH lower than 6 into less-photoreactive dichloramine (NHCl2) and radical scavenging by NH4+. The presence of chloride transformed HO• and SO4•- to Cl2•- that is less-reactive with 1,4-D, while the presence of dissolved O2 promoted gaseous nitrogen production. Results from this study suggest that the presence of chloramines can be beneficial to persulfate photolysis in the removal of 1,4-D; however, the treatment efficiency depends on a careful control of an optimal NH2Cl dosage and a minimal chloride residue.

A Path to Serious, Violent, Chronic Delinquency: The Harmful Aftermath of Adverse Childhood Experiences:

Abstract: Adverse childhood experiences can affect the development of a child in many ways, leading to highly maladaptive behaviors, such as serious, violent, and chronic (SVC) delinquency. This study uses d...

From carceral feminism to transformative justice: Women-of-color feminism and alternatives to incarceration

Abstract: Racial injustice at the intersections of interpersonal and state violence sets the stage for this examination of mainstream responses to domestic and sexual violence. At one end of this continuum i...

Search for charged Higgs bosons decaying into a top quark and a bottom quark at √s = 13 TeV with the ATLAS detector

Abstract: A search for charged Higgs bosons heavier than the top quark and decaying via H$^{±}$ → tb is presented. The data analysed corresponds to 36.1 fb$^{−1}$ of pp collisions at $ \sqrt{s}=13 $ TeV and was recorded with the ATLAS detector at the LHC in 2015 and 2016. The production of a charged Higgs boson in association with a top quark and a bottom quark, pp → tbH$^{±}$, is explored in the mass range from m$_{H}$± = 200 to 2000 GeV using multi-jet final states with one or two electrons or muons. Events are categorised according to the multiplicity of jets and how likely these are to have originated from hadronisation of a bottom quark. Multivariate techniques are used to discriminate between signal and background events. No significant excess above the background-only hypothesis is observed and exclusion limits are derived for the production cross-section times branching ratio of a charged Higgs boson as a function of its mass, which range from 2.9 pb at m$_{H}$± = 200 GeV to 0.070 pb at m$_{H}$± = 2000 GeV. The results are interpreted in two benchmark scenarios of the Minimal Supersymmetric Standard Model.

Rhodamine B degradation by nanosized zeolitic imidazolate framework-8 (ZIF-8)

Abstract: Adsorption and photodegradation of rhodamine B by ZIF-8 nanocrystals were studied using spectroscopic techniques coupled with density functional theory (DFT) cluster calculations. A fast adsorption rate was observed in the dark, but upon exposure to visible light or UV irradiation the adsorption rate noticeably increased. Although several studies previously reported this phenomenon involving bulk ZIF-8 powder, this is the first mechanistic study to our knowledge that demonstrates adsorption and degradation of rhodamine B by nanosized ZIF-8 under various light conditions. The combined study of N2 sorption pore analysis and surface-sensitive X-ray photoelectron spectroscopy (XPS) confirmed the surface adsorption was mainly due to the open metal sites and surface groups of nanoporous ZIF-8. The fluorescence studies suggested ZIF-8 nanocrystals were able to generate hydroxyl radicals in water but only under UV illumination. The work presented here provides an insight into understanding nanoscale metal–organic frameworks (MOFs) in the removal of organic molecules from wastewater.

Experiences with long acting injectable ART: A qualitative study among PLHIV participating in a Phase II study of cabotegravir + rilpivirine (LATTE-2) in the United States and Spain.

Abstract: Challenges with adherence to daily oral antiretroviral therapy (ART) among people living with HIV (PLHIV) have stimulated development of injectable long-acting (LA) regimens. We conducted 39 in-depth interviews with participants and providers in a Phase IIb study (LATTE-2) evaluating an injectable LA regimen in the U.S. and Spain. Interviews exploring participant and provider attitudes and experiences with LA versus oral ART were audiotaped, transcribed and analyzed using thematic content analysis. Participants described the convenience of LA injections versus daily pills and emotional benefits such as minimized potential for HIV disclosure and eliminating the "daily reminder of living with HIV." Providers recognized benefits but cautioned that LA candidates still need to adhere to clinic visits for injections and raised questions around ongoing clinical management. LA was seen as preferable to daily oral ART among PLHIV. Further research is needed regarding appropriate candidates, including with women and "non-adherent" populations across settings.

Function, distribution, and annotation of characterized cellulases, xylanases, and chitinases from CAZy.

Abstract: The enzymatic deconstruction of structural polysaccharides, which relies on the production of specific glycoside hydrolases (GHs), is an essential process across environments. Over the past few decades, researchers studying the diversity and evolution of these enzymes have isolated and biochemically characterized thousands of these proteins. The carbohydrate-active enzymes database (CAZy) lists these proteins and provides some metadata. Here, the sequences and metadata of characterized sequences derived from GH families associated with the deconstruction of cellulose, xylan, and chitin were collected and discussed. First, although few polyspecific enzymes are identified, characterized GH families are mostly monospecific. Next, the taxonomic distribution of characterized GH mirrors the distribution of identified sequences in sequenced genomes. This provides a rationale for connecting the identification of GH sequences to specific reactions or lineages. Finally, we tested the annotation of the characterized GHs using HMM scan and the protein families database (Pfam). The vast majority of GHs targeting cellulose, xylan, and chitin can be identified using this publicly accessible approach.

Sensitive Health Topics With Underserved Patient Populations: Methodological Considerations for Online Focus Group Discussions.

Abstract: Online focus group discussions provide an anonymous environment to assess sensitive, health-related experiences that may be difficult to discuss utilizing traditional face-to-face modalities, particularly for marginalized populations such as female-to-male trans masculine (TM) transgender individuals. This article reviews the history, advantages, and disadvantages of online focus groups, with an emphasis for research about sensitive issues with stigmatized, rare, and/or geographically dispersed patient populations. The article then evaluates the success of online focus group discussions as a case study using data from four asynchronous online focus groups conducted between September 2015 and February 2016 that explored topics related to sexual health care access with U.S. TM adults ( N = 29). The rationale for selecting an asynchronous online methodology is described along with the unique methodological considerations that emerged in developing the study protocol. We conclude by sharing lessons learned, including innovations for maximizing participant engagement and comfort to elicit rich qualitative data.