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OBJECTIVES: Although some existing indices quantified the mixture strength of state gun laws, methodological supports are still lacking. The study aimed to build a new state gun law strength (GLS) index, evaluate the contribution of all state gun laws to the new index, and assess the association between the new index and firearm homicide mortality. STUDY DESIGN: This is a population-based ecological study. METHODS: We condensed 134 state gun laws into a mixture GLS index at the state level to quantify each state's overall GLS by using the weighted quantile sum regression in each year from 1999 to 2018. The weights of state gun laws in the GLS index revealed their influence on GLS. The model also estimated the association between the GLS index and state-level firearm homicide mortality. RESULTS: From 1999 to 2018, 15 of 134 (11.19%) state gun laws significantly contributed to the GLS index for firearm homicide every year, five of which related to the minimum age of possessing firearms. The most influential gun law was "no possession of handguns until age 21." The GLS index was significantly and negatively associated with firearm homicide mortality; however, the association gradually diminished over time. CONCLUSIONS: The GLS index has methodological support and can take different gun violence outcomes into account. Future research can adopt the GLS index to conduct additional gun violence research or apply the modeling approach to build new GLS indexes for other gun violence outcomes.

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OBJECTIVE: Immune checkpoint inhibitors (ICIs) are a major advance in cancer treatment, but their payment benefits are unclear, resulting in financial risk. In Taiwan, the National Health Insurance Administration (NHIA) has adapted risk-sharing mechanisms to cover ICIs by collecting and assessing real-world evidence, such as case registration data, to adjust benefit packages for each medication, increase payment benefits of ICIs, and enable national health insurance sustainability. PATIENTS AND METHODS: This nationwide, multicenter, retrospective cohort study assessed the real-world use, effectiveness, and safety of ICIs reimbursed by the NHIA for treating multiple advanced cancers in Taiwan. We obtained data mainly from the NHIA Immune Checkpoint Inhibitor Registry Database. RESULTS: Between April 1, 2019, and March 31, 2020, 1644 patients received at least one dose of ICIs. The overall response rate (RR) was 29.1%. The metastatic urothelial carcinoma of patients ineligible for chemotherapy showed the highest RR. The estimated median progression-free survival (PFS) was 2.8 months (95% confidence interval [CI]=2.7-3 months), and renal cell carcinoma showed the longest PFS. The median PFS was reached in patients with most cancers except classic Hodgkin's lymphoma, which had a small sample size. The estimated survival probability was 50%. CONCLUSIONS: Under the national registration tracking system, Taiwan's high-cost drug policy has enabled access to new medicines and maximized patient benefits.

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OBJECTIVES: Gun violence is a pressing concern in the United States, where many laws targeting gun violence vary across states and localities. Studies have investigated the association between gun laws and gun violence, but not many focus on the role of time, which is critical for implementation. This study aims to determine the lagged association of gun laws with firearm homicide mortality to better understand the impacts of state gun laws over time. STUDY DESIGN: The design of this study is a longitudinal study. METHODS: This study applied the distributed lag non-linear model to assess the lagged association between firearm homicide mortality and the number of gun law provisions at the state level from 1999 to 2017. State gun law provisions were analyzed in aggregate and also across five groups of regulations. All estimates were transformed into relative risks (RRs). RESULTS: Regarding all state gun laws, regardless of how many gun law provisions were on the books in any year, a significantly reduced RR of firearm homicide mortality was not observed until 7 years later. Among the five regulation groups, a significant RR less than 1 was more likely to happen in longer lags ≥5. The lowest significant RR = 0.24 (95% confidence interval = 0.15, 0.39) was observed in the gun types, components, and trafficking group at lag 8. All regulation groups had an overall impact to reduce significantly the RR of firearm homicide mortality with more gun law provisions, except for the dealer regulation group. CONCLUSIONS: State gun law provisions appear to impact firearm homicide mortality differently over time. This emphasizes the centrality of enforcement. Firearm policy researchers need to consider how specific gun laws are implemented over time to help inform law-based interventions.

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Attention-deficit/hyperactivity disorder (ADHD) is male predominated, and the etiology of this disorder remains unclear. Past studies have assessed the association of low-level organophosphate pesticide exposure with childhood ADHD cross-sectionally and prospectively. However, the results have been inconsistent. A first case-control study was performed to investigate the relationship between organophosphate pesticide exposure and ADHD with adjusted covariates. We recruited 97 doctor-diagnosed ADHD cases and 110 non-ADHD controls who were 4-15 years of age. Exposure was assessed using urinary levels of dialkylphosphate metabolites, which are biomarkers of OP pesticide exposure. Blood lead levels and polymorphisms of two commonly verified dopaminergic-related genes (the D4 dopamine receptor gene DRD4 and the dopamine transporter gene DAT1) were also analyzed. The sociodemographics and lifestyles of the children and of the mothers during pregnancy were collected using a questionnaire. The blood lead levels of both groups were similar (1.57 ± 0.73 vs. 1.73 ± 0.77 µg/dL, p = 0.15). Significant urinary concentration differences in one of the six dialkylphosphate metabolites, dimethylphosphate (DMP), were found between ADHD and control subjects (322.92 ± 315.68 vs. 224.37 ± 156.58 nmol/g cr., p < 0.01). A dose-response relationship was found between urinary concentrations of DMP and ADHD in both crude and adjusted analyses (p for trend<0.05). Children with higher urinary DMP concentrations may have a twofold to threefold increased risk of being diagnosed with ADHD. We report a dose-response relationship between child DMP levels and ADHD. Organophosphate pesticide exposure may have deleterious effects on children's neurodevelopment, particularly the development of ADHD.

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The purpose of this study was to investigate the relationships between clinical factors (including haemoglobin value, chemotherapeutic agents, and corticosteroid use) and changing patterns of fatigue before and for the next 10 days following the start of a new round of chemotherapy in children with cancer. A prospective longitudinal design was used to collect data from 48 paediatric oncology patients who were about to begin a new round of chemotherapy and their parents. Fatigue levels were assessed using multidomain questionnaires with three categories of patient self-report (including 'General Fatigue', 'Sleep/Rest Fatigue', and 'Cognitive Fatigue') and four categories of parent proxy-report (including 'Lack of Energy', 'Unable to Function', 'Altered Sleep', and 'Altered Mood'). The findings suggest that fatigue from both patient self-report and parent proxy-report changed significantly over time. The major findings from this study are that patients have more problems with fatigue in the first few days after the start of a cycle of chemotherapy. Corticosteroid use and haemoglobin value were associated with significant increases in fatigue that were sustained for several days and reached the highest level of fatigue at day 5 for those receiving concurrent steroids. The association of chemotherapeutic agents with fatigue varied between patient self-report and parent report, but the type of chemotherapeutic agents used was not associated with most changes in fatigue.

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OBJECTIVE: The aim of this study was to assess the relationship between fish consumption and total mercury concentration in maternal blood, umbilical cord blood, and placenta tissue of pregnant women in Taiwan. DESIGN: Cross-sectional study. SETTING: A medical centre in Taipei, Taiwan. SAMPLE: Sixty-five pregnant women delivered between July 2004 and March 2005. METHODS: We administered a questionnaire to each woman in the third trimester and collected blood samples and placenta tissue after delivery. Mercury concentrations in the maternal blood, cord blood and placenta tissue were measured using mercury analyser (Hiranuma HG-310, Hitachi, Japan). A dietitian calculated the quantity of fish consumed from the questionnaire. MAIN OUTCOME MEASURES: The total mercury concentration in maternal blood, cord blood and placenta tissue. RESULTS: The mean total mercury concentration in maternal blood, cord blood and placenta tissue was 9.1 +/- 0.40 microgram/l, 10.0 +/- 0.55 microgram/l and 19.2 +/- 1.8 ng/g, respectively. Eighty-nine percent of the maternal blood mercury concentrations exceeded the US National Research Council recommended value of 5.8 microgram/l. Fish consumption while pregnant correlated significantly with maternal blood and cord blood mercury concentrations. CONCLUSIONS: Total mercury concentrations of maternal blood, cord blood and placenta tissue commonly exceeded recommended values, and were higher in women who ate fish more than three times a week while pregnant.

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The correlation between orientation ordering of polymer chains in the bulk of polymer film and at the polymer-liquid-crystal (LC) interface has been studied to determine it's role in LC alignment. The bulk and surface ordering of polymer were investigated by null ellipsometry and x-ray reflectivity, respectively. Two kinds of liquid-crystalline polymers were used; side-chain azopolymers with azochromophores containing hydrophobic OC4H9 alkyl chain (P1) and strongly polar NO2 group (P2) as the end substituents. The uniaxial tilt orientation of azochromophores in the films of both polymers was induced by the oblique irradiation with unpolarized UV light. The two polymers exhibit similar chain orientation but different ordering of azochromophores on the surface of the films of P1 and P2. Surface ordering of P1 films correlates very well with the order in the bulk of the film, which are essentially determined by the UV exposure. However, orientational order of polymer chains at the surface of P2 films is different from that in its bulk and is not determined by UV exposure. This is explained by strong aggregation of azochromophores during its self-assembling at the polymer-air interface. The LC alignment is determined by the surface ordering of azochromophores. The results imply that ordering tendency can be effectively transferred from polymer bulk to polymer surface and then to LC if it is not lost at the polymer-LC interface.

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We apply experimental technique based on the combination of methods dealing with principal refractive indices and absorption coefficients to study the photoinduced three-dimensional (3D) orientational order in the films of liquid crystalline (LC) azopolymers. The technique is used to identify 3D orientational configurations of trans azobenzene chromophores and to characterize the degree of ordering in terms of order parameters. We study two types of LC azopolymers which form structures with preferred in-plane and out-of-plane alignment of azochromophores, respectively. Using irradiation with the polarized light of two different wavelengths, we find that the kinetics of photoinduced anisotropy can be dominated by either photoreorientation (angular redistribution of trans chromophores) or photoselection (angular selective trans-cis isomerization) mechanisms depending on the wavelength. At the early stages of irradiation, the films of both azopolymers are biaxial. This biaxiality disappears on reaching a state of photosaturation. In the regime of photoselection, the photosaturated state of the film is optically isotropic. But, in the case of the photoreorientation mechanism, anisotropy of this state is uniaxial with the optical axis dependent on the preferential alignment of azochromophores. We formulate the phenomenological model describing the kinetics of photoinduced anisotropy in terms of the isomer concentrations and the order parameter tensor. We present the numerical results for absorption coefficients that are found to be in good agreement with the experimental data. The model is also used to interpret the effect of changing the mechanism with the wavelength of the pumping light.

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Any polar-ordered material with a spatially uniform polarization field is internally frustrated: The symmetry-required local preference for polarization is to be nonuniform, i.e., to be locally bouquet-like or "splayed." However, it is impossible to achieve splay of a preferred sign everywhere in space unless appropriate defects are introduced into the field. Typically, in materials like ferroelectric crystals or liquid crystals, such defects are not thermally stable, so that the local preference is globally frustrated and the polarization field remains uniform. Here, we report a class of fluid polar smectic liquid crystals in which local splay prevails in the form of periodic supermolecular-scale polarization modulation stripes coupled to layer undulation waves. The polar domains are locally chiral, and organized into patterns of alternating handedness and polarity. The fluid-layer undulations enable an extraordinary menagerie of filament and planar structures that identify such phases.

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A first generation of dendrimeric Y-enynes with extended flexible chains was synthesized using Sonogashira coupling. Dendrimers 9 and 10 are highly fluorescent in the solid state and in solution.

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The transfer of chirality from nonchiral polymer networks to the racemic B2 phase of nonchiral banana-shaped molecules is demonstrated. This corresponds to the transfer of chirality from an achiral material to another achiral material. There are two levels of chirality transfers. (a) On a microscopic level the presence of a polymer network (chiral or nonchiral) favors a chiral state over a thermodynamically stable racemic state due to the inversion symmetry breaking at the polymer-liquid crystal interfaces. (b) A macroscopically chiral (enantimerically enriched) sample can be produced if the polymer network has a helical structure, and/or contains chemically chiral groups. The chirality transfer can be locally suppressed by exposing the liquid crystal to a strong electric field treatment.

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Null-transmission ellipsometry and depolarized light microscopy have been performed on free-standing films of three achiral banana-shaped compounds in the B2 phase. Our results support a two-layer unit cell previously proposed to explain the observed antiferroelectricity in thin films and bulk samples. We have studied thicker films than previously reported and have found no deviations in the film structure from the earlier findings. Moreover, we can determine the layer spacing, the molecular tilt from the layer normal, and the three principal indices of refraction in the molecular reference frame.

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Data on concentrations of trihalomethanes (THMs) in raw and chlorinated water collected from three water treatment plants in Taiwan and estimates of the lifetime cancer risk for THMs from drinking water, using age-adjusted factors and volatilization terms, are presented. Data on THM levels in drinking water were obtained from the annual reports of the Environmental Protection Administration (EPA) of Taiwan. The methodology for estimation of lifetime cancer risks was taken from the USEPA. Chloroform was the major species of THMs, especially in the water plant of south Taiwan. Chloroform contributed the majority of the lifetime cancer risks (range: 87.5-92.5%) of total risks from the three water supply areas. All lifetime cancer risks for CHCl(3), CHBrCl(2), CHBr2Cl, and CHBr3 from consuming tap water in the three water supply areas were higher than 10(-6). The sum of lifetime cancer risks for CHCl(3), CHBrCl(3), CHBr2Cl, and CHBr3 was highest (total risk for total THMs<1.94x10(-4)) for tap water from south Taiwan.

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Pollutant concentrations detected in oysters from 12 different culture areas of Taiwan (especially for the Hsiangshan area and the Machu Islands) from 1991-98 were evaluated to investigate potential carcinogenic (inorganic As and organochlorine pesticides) and non-carcinogenic (Cu, Zn, Cd and inorganic As) risk to the public from ingestion of the oysters. The highest geometric mean (GM) Cu and Zn concentrations of 1108 (range 113-2806) and 1567 (range 303-3593) microg/g dry weight were obtained in oysters from the Hsiangshan coastal area. The maximum GM Cd and As concentrations of 6.82 and 19.3 microg/g dry weight were found in oysters from the Machu Islands area. The p,p'-DDE values range from not detectable in Penghu Islands' oysters to 164 ng/g dry weight in Machu Islands' oysters. The highest tDDT (sum of p,p'-DDE, p,p'-DDD and p,p'-DDT) concentrations of 337 and 340 ng/g dry weight were found in oysters from Kimmen and Machu Islands, respectively. A calculated target hazard quotient (THQ; daily intake/reference dose) of 11.4 (based on 139 g oysters/day) for Cu caused by consuming oysters from the Hsiangshan area is higher than that from other areas (range 0.124-5.95). The highest average Cu intake from Hsiangshan's oysters for individuals is 11.4 times (i.e. THQ=11.4) more than that of reference dose (40 microg/kg/day). However, the maximum THQ values for Cd and As caused by consuming oysters collected from the Machu Islands were 5.57 and 2.63 for Cd and As, respectively. Generally, the results of THQ showed that if only the maximally exposed individuals were considered, the value of 65.4% for oyster was higher than 1.0 in comparison with reference dose. All cancer risk estimates for inorganic As from consuming oysters were higher than 10(-6) (range from 128x10(-6) to 509x10(-6) for maximally exposed individuals and range from 17.1x10(-6) to 68.0x10(-6) for typically exposed individuals, respectively); that is the risk of the lower end of the range of acceptable risk. The highest risk estimate for inorganic As was 509x10(-6) for consumption of oysters by Machu Islands' residents. The lifetime cancer risks of 19.0x10(-6) for tDDT by consuming oysters from the Machu Islands was higher than those from the Penghu Islands (0.37x10(-6)). Therefore, the sum of lifetime cancer risks for tDDT and inorganic As had the highest risks (total risk=528x10(-6)) of consuming oysters from the Machu Islands. Furthermore, a 10(-6) upper limit on lifetime risk as the health protection standard would require maximum oyster consumption rates of approximately 0.26 g/day.

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A small number of bifunctional monomers are mixed with a nematic liquid crystal (LC) and cured with a distributed electric field, which is produced by a circular-hole-patterned electrode structure. A gradient type of lens, that is, a LC microlens, is investigated for various polymer concentrations. Addition of 3% polymer is enough to freeze the gradient-index properties of the structure in the form of a convex lens, and a polymer-stabilized LC microlens is demonstrated. Although a lower concentration of polymer cannot hold the distribution properties in a curing process, it can maintain the variable focus as a nematic material can. The polymer networks can also eliminate the disclination line that usually appears and causes the lens in this type of LC device to deteriorate.

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