bluuebunny/crossref_metadata_2025 huggingface dataset:
Porosity inversion of 1-D two-phase medium with wavelet multiscale method
Authors: Zhang Xin-Ming  , Liu Jia-Qi  , Liu Ke-An  ,   (1)哈尔滨工业大学，哈尔滨  150001; (2)哈尔滨工业大学深圳研究生院，深圳  518055
Published: December 2020

Based on the idea of multiscale approximation, a wavelet multiscale method is proposed by combining the wavelet analysis and multiscale inversion strategy, and applied to the inversion of porosity in the two-phase medium. The inverse problem is decomposed to multiple scales with wavelet transform and hence the original inverse problem is re-formulated to a set of sub-inverse problem corresponding to different scales and is solved successively according to the size of scale from the smallest to the largest. On each scale, regularized Gauss-Newton method is carried out, which is stable and fast, until the optimum solution of original inverse problem is found. The wavelet multiscale method is described as the combination of three operators: the restriction operator, the relaxation operator and the prolongation operator. And then the flow of wavelet multiscale method is outlined and the restriction operator matrix and the prolongation operator matrix obtained by adapting the compactly supported orthonormal wavelet Daubechies wavelets are deduced. The inversion results obtained by wavelet multiscale method are compared with those with traditional regularized Gauss-Newton method, the results of numerical simulation demonstrated that the method is an effective and widely convergent optimization method.
Autofluorescence lifetime imaging of lipofuscin and oxidized melanin in retinal pigment epithelium cells
Authors: Sun Yi-Wen  , Qu Jun-Le  , Zhao Ling-Ling  , Xu Gai-Xia  , Ding Zhi-Hua  , Niu Han-Ben  ,   (1)光电子器件与系统教育部重点实验室，深圳大学光电子学研究所,深圳  518060; (2)光电子器件与系统教育部重点实验室，深圳大学光电子学研究所,深圳  518060；浙江大学现代光学仪器国家重点实验室,杭州  310027; (3)浙江大学现代光学仪器国家重点实验室,杭州  310027
Published: December 2020

We report on our investigation of the spatial distribution and autofluorescence lifetime characterization of lipofuscin and oxidized melanin in the retinal pigment epithelium cells of the pig eye using a two-photon excitation fluorescence lifetime imaging microscopy (TPE-FLIM) system, which that is based on a time-correlated single photon counting technique. In particular, we analyzed the difference of autofluorescence lifetimes of these pigment granules in light-induced oxidizing environment. The experimental results showed that the fluorescence lifetime imaging can provide an effective differentiation of multi-component fluorophores, and fluorescence decay can be used to distinguish normal from abnormal fluorescence. TPE-FLIM has the potential to provide a high sensitive imaging instrument for the clinical diagnosis and pathological studies in ophthalmology, and is also of significance to the study of aging mechanism of cells in the fundus.
A tunable wavelength routing scheme based on the sum-and difference-frequency generation with double pass configuration and its applications
Authors: Yu Song  , Zhang Hua  , Shen Jing  , Zhang Yong-Jun  , Gu Wan-Yi  ,   北京邮电大学，光通信与光波技术教育部重点实验室，北京  100876
Published: December 2020

A tunable wavelength routing scheme based on sum- and difference- frequency generation (SFG+DFG) is proposed, where the concept of double pass configuration is employed. An arbitrary channel can be dropped from a WDM signal and added to another WDM signal at arbitrary wavelength. Therefore, the tunable wavelength conversion and wavelength routing are integrated together in this scheme. The theoretical expression of the input signal wave and the converted wave are derived under the assumption of “small signal" when the phase is matched perfectly. Numerical calculations were performed which showed that the cross-talk can be suppressed provided the spacing of the WDM channels is greater than 02nm (25GHz). If the input or output of this device is changed, this scheme can be utilized as tunable wavelength add multiplexer, tunable wavelength drop multiplexer, wide tunable wavelength filter or tunable wavelength converter. A wavelength interchange cross connection (WIXC) unit can also be realized by employing two devices of this scheme.
Study on the electrical potential signals induced by laser plasma in the target with bias-voltage
Authors: Ji Yun-Jing  , Bian Bao-Min  , Tong Chao-Xia  , Lu Jian  ,   南京理工大学信息物理与工程系，南京  210094
Published: December 2020

The electrical potential signals induced by laser-plasma generated on a copper target with bias-voltage using a Nd:YAG laser (7ns) were detected, and the effect of the additional voltage on the potential signals was mainly studied. The experimental results show a single-peak distribution in the temporal profile, which is positive for negative bias voltage and negative peak when with positive bias voltage. Taking into account the effect of plasma charging and the electric field produced by the target bias-voltage, a clear explanation of the observed effect is given.
Consistency of splitting frequency difference with longtudinal modes spacing variation in Zeeman dual-frequency laser
Authors: Liu Wei-Xin , Tang Ning , Ma Long-Xing , Gao Ke-Fan , Sun Ming-Zhe ,   Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment, Institute of Space Sciences, Shandong University, Weihai 264209, China
Published: December 2020

Phase anisotropy in laser resonant cavity will bring about an influence on laser frequency and polarization, such as laser frequency splitting, of which the frequency difference is determined by their introduced phase retardation. For a helium-neon laser with a small phase retardation in the cavity, the two split modes are very close to each other whose burned holes are overlapped. Then only one mode oscillates while the other is always in lock-in state due to strong mode competition, which forms hidden frequency split. Meanwhile the spacing between adjacent longitudinal modes deviates from original value and produces a certain variation equal to twice the hidden splitting frequency difference. As a result the longitudinal modes spacing variation is dominated by the phase retardation. On the other hand, by applying transverse magnetic field to a laser tube along the polarization direction, the neon atoms will undergo transverse Zeeman effect and be divided into two groups to provide the gain for polarized light beams parallel to the magnetic field and perpendicular to the magnetic field respectively. Then the laser mode competition is greatly weakened so that the two split modes can oscillate simultaneously to obtain the frequency difference. In order to make profound study of the consistency between longitudinal mode spacing variation and splitting mode frequency difference in the presence of transverse magnetic field, the samples of tilted quartz plate or half wave plate is placed into laser cavity to produce phase retardation. By the two mentioned methods, the splitting frequency difference varying with phase retardation of samples is deduced to make a comparison. Two measurements show that the average relative deviation is less than 1%, while the experimental results accord with theoretical analyses quite well. In this way splitting frequency difference of Zeeman dual-frequency laser can be determined accurately, and a new method to measure the phase retardation of half wave plate is provided.
Measuring stress in podiatric students in Spain: psychometric validation and adaptation of the KEZKAK questionnaire
Authors: Ortega-Avila Ana Belen , Cervera-Garvi Pablo , Jimenez-Cebrian Ana Maria , Chicharro-Luna Esther , Garcia-Paya Irene , Gijon-Nogueron Gabriel
Published: December 2020

Objective

The study aim was to develop a linguistic-cultural adaptation of the KEZKAK questionnaire to be completed during the practicum of podiatric medical students in Spain, to validate the questionnaire and to evaluate its psychometric properties.

Methods

The cross-sectional study was carried out in two stages: 1. Cross-cultural adaptation; 2. Clinimetric validation based on assessments of interobserver reliability, test-retest reliability and internal consistency. The participants were podiatric medical students at the universities of Malaga and Miguel Hernandez, Alicante (Spain) and were recruited during the period February–October 2019. The following inclusion criteria were applied: aged at least 18 years, studying the third or fourth year of a university degree in Podiatry. All gave signed informed consent and completed the State-Trait Anxiety Inventory and the Podiatry version of the KEZKAK questionnaire. No sampling was performed and thus the entire eligible population was included in the study.

Results

The analysis was based on 205 participants (33.5% male, 66.5% female), with a mean age of 23.05 (SD 5.37) years. Internal consistency was excellent, with a Cronbach’s alpha of 0.95. This version of the questionnaire had five factorial structures (61.18%). No floor/ceiling effect was observed in any item. The KEZKAK presented high test-retest reliability after 21 days, with an overall ICC of 0.95 (95% CI [0.93–0.98]).

Conclusion

For university students of podiatry in Spain, the KEZKAK Podiatry version questionnaire is a valid, reliable instrument for measuring stressors during the practicum.
Experimental lung injury induces cerebral cytokine mRNA production in pigs
Authors: Kamuf Jens , Garcia Bardon Andreas , Ziebart Alexander , Frauenknecht Katrin , Folkert Konstantin , Schwab Johannes , Ruemmler Robert , Renz Miriam , Cana Denis , Thal Serge C. , Hartmann Erik K.
Published: December 2020

Background

Acute respiratory distress syndrome (ARDS) is an important disease with a high incidence among patients admitted to intensive care units. Over the last decades, the survival of critically ill patients has improved; however, cognitive deficits are among the long-term sequelae. We hypothesize that acute lung injury leads to upregulation of cerebral cytokine synthesis.

Methods

After approval of the institutional and animal care committee, 20 male pigs were randomized to one of three groups: (1) Lung injury by oleic acid injection (OAI), (2) ventilation only (CTR) or (3) untreated. We compared neuronal numbers, proportion of neurons with markers for apoptosis, activation state of Iba-1 stained microglia cells and cerebral mRNA levels of different cytokines between the groups 18 hours after onset of lung injury.

Results

We found an increase in hippocampal TNFalpha (p < 0.05) and IL-6 (p < 0.05) messenger RNA (mRNA) in the OAI compared to untreated group as well as higher hippocampal IL-6 mRNA compared to control (p < 0.05). IL-8 and IL-1beta mRNA showed no differences between the groups. We found histologic markers for beginning apoptosis in OAI compared to untreated (p < 0.05) and more active microglia cells in OAI and CTR compared to untreated (p < 0.001 each).

Conclusion

Hippocampal cytokine transcription increases within 18 hours after the induction of acute lung injury with histological evidence of neuronal damage. It remains to be elucidated if increased cytokine mRNA synthesis plays a role in the cognitive decline observed in survivors of ARDS.
A DETAILED REVIEW ON THE TYPES AND APPLICATIONS OF NANOPARTICLES OR NANOMEDICINE
Authors: Kumari Nutan , Tripathi Ankita , Chaudhar Sapna , Mehta Bhawna , Bhardawaj Khushboo
Published: December 2020

Nanoparticles are an emerging field of modern science. It is solid colloidal particles. They consist of micro molecular materials in which the active ingredients is dissolved, entrapped or encapsulated or adsorbed or attached. The size of nanoparticles ranges from 1 to 100 nm. It can be synthesized chemically or biologically. Nanoparticles are used in various purposes like in drug delivery, in food, in medicine, in cosmetics etc. There are lots of advantages of nanomedicine over other dosage form. Nanoparticles show high solubility as well as higher bioavailability on site of action. This review focuses on synthesis, biosynthesis, types, application, advantage, disadvantage, limitation of nanoparticle.
PRELIMINARY VALIDATION OF UV SPECTROPHOTOMETRIC FOR DETERMINATION OF ANTIEMETIC DRUG APREPITANT IN BULK FORM
Authors: Kumari Anuradha , Kaur Parminderjit
Published: December 2020

Objective: The main objective of this work was to put forth the assorted strategies to develop and validate a novel, specific, precise and reliable method for estimation of aprepitant in bulk using UV-visible spectroscopy method. Method: The validation of Aprepitant was done by using UV-visible spectrophotometric method by using double beam systronics UV-visible spectrometer, model UV-2201 (India). The validation method involves various parameters like linearity, precision, accuracy, robustness, ruggedness, detection, quantification limits of formulation analysis according to International Conference on Harmonization (ICH) guidelines. Results: UV-spectroscopic determination was carried out at maximum absorption 263.6nm using pH 6.8 buffer & 1.1% tween 80 and 263.8nm using methanol and distilled water. The method obeyed Beer Lambert’s Law in the concentration range of 8-48µg/ml and R2 was found to be 0.999. Conclusion: As per the results were concerned, the %RSD was found to be less than 2% which is compliance with the acceptance criteria of Q1 (R1) and According to results, the currently developed method shows compliance with acceptance criteria with Q1 (R1) and international conference on harmonization (2005) guidelines. Thus, the developed method was found to be simple accurate and précised.
The Effect of Participation in Farmer Groups on Household Adoption of Sustainable Land Management Practices in Kenyan Drylands
Authors: Karaya Rebecca N. , Onyango Christopher A. , Ogendi George M.
Published: December 2020

Land degradation is a major cause of declining yields and loss of dryland ecosystems resilience in the Lake Baringo Basin in Kenya. One of the solutions to land degradation in drylands is the application of Sustainable Land Management (SLM) technologies. Improving farmers’ capacity to adopt SLM technologies has been an important strategy of the Kenyan government and her development partners to addressing land degradation. State agricultural extension services are charged with the role of building this capacity. Unfortunately, such extension services have had little impact in the Kenyan drylands. To counter this inadequacy in extension services, farmers have formed grass-root organisations to foster networks of support and information sharing. In this paper, we analysed the effect of participation in farmers organisation in promoting adoption of SLM practices by agropastoralists in the Lake Baringo Basin. Data were collected through in-depth household interviews with 150 farmers, 79 of them group members and 71 non-group members. Level of knowledge, sources of information and challenges of SLM adoption were studied. The study revealed significant and positive association between group participation and adoption of SLM practices at X2 (3, N=150=63.209, P=0.000). Additionally, group partnering with development agencies like Non-Governmental Organisations (NGOs) and government departments was reported to have significant influence on household adoption of SLM practices at X2 (3, N=79=13.147, P=0.004). The results indicated that farmer groups can effectively be used to leverage farmers' adoption of SLM innovations and potentially improve household income and food security in the Kenyan drylands. We recommended organizational and resource capacity building for farmer groups to promote their effectiveness in provision of resources and services to their members. In addition, government research and extension agencies and academia should consider forming collaborations with farmer groups in generation of SLM technologies that are suited to the farmers location and prevailing context.
Psychological Burnout among Tutors in Colleges of Education in the Ashanti Region, Ghana
Authors: Ofori Kennedy Nyeseh , Kyere Eunice Agyeiwaa , Berko Lydia Boateng
Published: December 2020

This paper identifies the antecedents of psychological burnout and its influence on tutors’ job stress in Colleges of Education in the Ashanti Region of Ghana. The study adopted a case study approach because it probes four specific Colleges of Education (COE) in the Ashanti Region of Ghana. Quantitative research method was employed. Cluster sampling was used in selecting 120 tutors and then stratified on the basis of gender. The study used questionnaire as the main research instrument for gathering the data from participants. Cronbach’s Alpha was used to test the sample reliability, which yielded coefficient 0f 0.84. Data were analyzed using inferential statistics, with Pearson Product Moment Correlation and multiple regression models as analytical tools. Hypothesis was tested at a significant level of 0.01 and 0.05. Results revealed that lack of job satisfaction (96 %) and delay in payment of salary (88%) were the leading antecedents of psychological burnout among the tutors. Again, the findings showed that lack of commitment to work (92%) and transferring of aggression to teacher trainees were the top most effects of stress on Tutors. Results of hypothesis tested revealed no significant difference on the expression on both the causes and effects of psychological burnout among tutors on the basis of gender.  It was concluded that inadequate or complete lack of academic facilities did not only impair academic productivity, but also exerted undue stress on tutors and available facilities. The study recommended among others, the development priorities of the colleges should be Tutor –teacher trainee oriented.
Perception and Practices of Home Management of Acute Watery Diarrhoea and Its Impact on Dehydration
Authors: Uddin M. Z. , Fatema K. , Begum R. S. , Saad T. , Hossain M. M. , Khan A. R. M. S. H. , Mohsin M.
Published: December 2020

Background: Diarrhoea is one of the commonest causes of death in children in developing countries. Proper home management can reduce morbidity and mortality. High rates of dietary restriction, poor knowledge of preparation of ORS solutions and low attention given to clinical indicators are causes for seeking hospital management. This study was done to observe the knowledge of caregivers regarding home management of acute watery diarrhoea and to assess the impact of home management on severity of dehydration.

Methods: This study was a prospective study carried out on children with acute diarrhea who attended outpatient department (OPD) of Rangpur Medical College Hospital and duration of the study was 6 months. A total of 100 cases were included in this study who fulfilled the definition of acute diarrhea by WHO. The investigator questioned each mother with the help of a preformed questionnaire.

Results: In 85% of cases, caregivers perception about diarrhea was an increase in the frequency and fluidity of stool. About 95% of cases were initially treated at home; treatment was given at home with ORS (95%). There was change in feeding pattern and modified food was given (24%). Perception about ORS preparation was appropriate in 64% and inappropriate in 31% of cases. Inadequate amount of ORS was given in 74% cases. There was no interruption of breast feeding; dietary restriction during diarrhoea was observed only in 2% cases. Most of the parents did not know when to return immediately to hospital.  Dehydration status of diarrhoeal cases was no dehydration (81%), some dehydration (18%) and severe dehydration (1%). In majority of the cases different drugs were used.

Conclusion: Most of the caregivers’ decided to treat diarrhoea at home. Many of them had wrong perception about preparation of ORS and some of them did not know how to make ORS solution. Inadequate amount of ORS was given in most of the cases. Thus to lessen hospital burden and to prevent dehydration increased emphasis should be given to health education of home management of diarrhea.
Performance of F2 Rice (Oryza sativa L.) Segregants Derived from a Cross the BPT-5204 / IR-64Drt1
Authors: Kumar Anjani , Singh D. N. , Prasad Krishna , Pandey Avinash
Published: December 2020

The present investigation was carried out with F2 plants from a cross between two parents i.e., BPT-5204 and IR-64Drt1. The selection of parents for crosses was made based on genotypes that were tolerant and susceptible to drought condition. BPT-5204 was drought susceptible and IR-64Drt1 was also tolerant to drought. In this experiment adequate amount of variability was detected for grain yield per plant and its components among 324 segregants evaluated under augmented randomized block design II in normal field condition. The analysis of variance for grain yield and its attributing characters among blocks, treatments, entries, checks and checks vs entries revealed presence of significant variation in the segregants studied. However, with respect to checks, non-significant differences were recorded for only L/B ratio. The results indicated that among 324 rice genotypes including checks, only 9 rice genotypes expressed higher yield compared to seven checks varieties under normal field condition. The segregants S-51, S-122, S-135, S-195, S-199, S-210, S-219, S-222, S-251 were top ranking genotypes with respect to all checks.
Changing Rainfall and Swinging Tea Production: The Correlates and Perception of Social Ecology of Tea Garden
Authors: Jairu Dristika , Acharya S. K. , Mandal Anwesha
Published: December 2020

Tea is the second most commonly consumed beverages, after water, across the globe. However, the quality and aroma of the produce largely depends on different climatic factors like temperature, rainfall, altitude etc. Even a slight alteration in these climatic factors, affects the quality and production adversely. Climate change, a global challenge, is a big threat to the tea industry as well as its workers. With degraded quality and swinging production due to changing rainfall and temperature, hundreds of tea gardens have been closed down in the past few decades, putting livelihood of thousands of tea workers to question. This paper attempts to find how the changing rainfall and swinging tea production varies with the profile characteristics of the tea workers. The study was conducted in the Darjeeling, Kalimpong and Dooars districts of West Bengal with 90 randomly selected tea workers from nine randomly selected tea gardens, three each belonging to three different altitudes. All the results has been analyzed using statistical tools of correlation coefficient, multiple and stepwise regression and path analysis. The results shows that treatment and mobility are two important variable explaining the variation in perception on change in rainfall and perception on tea production respectively. It has also been found that variables like income, treatment and garments have been reliable predictors for estimating the change in rainfall whereas the variable mobility exhibits a positive and significant relationship with perceived change in tea production. The regression analysis showed that treatment has explained 19.4 per cent of total variation in case of perceived change in rainfall and mobility has explained 16 per cent of total variance in case of perceived change in tea production.
Microbiological Analysis of Zobo Drink Preserved with Scent Leaves (Ocimum gratissimum)
Authors: Udensi Chukwuma G. , Nwankpa Ugonna D. , Amanze Emmanuel K. , Nwokafor Chibuzor V. , Udekwu Chinedu E. , Ndubuisi Chibuzor W.
Published: December 2020

Aim: To determine the microbiological quality of zobo drink preserved with scent leaves.

Methods: The zobo drink and scent leaves were prepared and evaluated using standard microbiological techniques.

Results: Twenty three (23) bacteria species and fourteen (14) fungi species were identified from zobo drink preserved with scent leaves samples. This reveals the major bacterial species to be Enterobacter spp, Staphylococcus aureus, Bacillus spp, and Micrococcus spp. and fungi species to be Aspergillus niger, Rhizopus spp and Penicillium spp. The bacterial and fungal counts decreased as the days increased with day 1 having the highest bacterial and fungal counts at 1.41x105 (cfu/ml) and 3.1x104 (cfu/ml) respectively. The control samples were generally higher than the counts recorded on the bacterial and fungal counts. Zobo + scent leaves (ZSC) recorded the highest bacterial count at 1.41x105 (cfu/ml), while the least was recorded for (ZSA) at 1.01x106 (cfu/ml). Zobo + Scent (ZSC) recorded the highest fungal counts at 3.1x104 (cfu/ml), while the least was recorded for ZSA at 1.2x105 (cfu/ml). From this study, Bacillus spp and Staphylococcus aureus were the most frequently occurring bacterial isolates with a high percentage occurrence of 8(21.6%) and 6(16.2%), while Penicillium spp was the most frequently occurring fungal isolate.

Conclusion: The association of these microorganisms with foods such as the commercial zobo drinks may be as a result of poor hygiene or poor sanitary condition. The microbial counts showed that among the zobo drink preserved with scent leaves samples, zobo + scent leaves (ZSC) is the most predisposed product to microbial population due to the high microbial counts recorded. Therefore, the result revealed that the samples of zobo drink were directly and indirectly contaminated with high levels of pathogenic bacteria, but can be reduced by the addition of scent leaves as a preservative.
Association of p155/140 Autoantibody With Loss of Nailfold Capillaries but not Generalized Lipodystrophy: A Study of Ninety‐Six Children With Juvenile Dermatomyositis
Authors: Khojah Amer , Liu Victoria , Savani Sonia I. , Morgan Gabrielle , Shore Richard , Bellm Jackie , Pachman Lauren M.
Published: December 2020

Objective

Myositis‐specific antibodies (MSAs) facilitate grouping children with juvenile dermatomyositis (DM) into distinct phenotypes. The first aim of this study was to investigate the link between anti‐p155/140 and lipodystrophy as determined by dual x‐ray absorptiometry (DXA) assessment of fat distribution. The second aim was to examine the relationship between anti‐p155/140 and damage to the nailfold capillary system.

Methods

Children with juvenile DM followed for a minimum of 5 years were included. The study population was divided into 3 groups (anti‐p155/140, other MSA, and MSA negative). Lipodystrophy was assessed by physician assessment and DXA fat distribution (trunk‐to‐leg fat ratio). Documentation of nailfold capillary end row loops (ERLs) was obtained at diagnosis.

Results

A total of 96 subjects (44% anti‐p155/140, 23% other MSA, 33% MSA negative) were included. There was no significant difference in age, disease activity scores, or lipodystrophy between the 3 groups. The trunk‐to‐leg fat ratios were similar among the 3 groups at different time points. However, the anti‐p155/140 group had significantly decreased ERL counts (P = 0.006) at baseline as well as a prolonged duration of untreated disease at diagnosis (P = 0.027). Also, the anti‐p155/140 group had fewer patients with a monophasic disease course than the other 2 groups (P = 0.008).

Conclusion

Generalized lipodystrophy frequency was equivalent in all 3 groups based on physician assessments and trunk‐to‐leg fat ratios. The anti‐p155/140 group had a greater loss of ERLs, suggesting that this MSA may impact the vascular component of juvenile DM.
High Figure‐of‐Merit Gallium Oxide UV Photodetector on Silicon by Molecular Beam Epitaxy: A Path toward Monolithic Integration
Authors: Mukhopadhyay Partha , Hatipoglu Isa , Sakthivel Tamil Selvan , Hunter Daniel A. , Edwards Paul R. , Martin Robert W. , Naresh-Kumar Gunasekar , Seal Sudipta , Schoenfeld Winston V.
Published: December 2020

A high figure‐of‐merit UV‐C solar‐blind photodetector (PD) fabricated from thin‐film beta‐gallium oxide (β‐Ga2O3) grown on n‐Si substrates by plasma‐assisted molecular beam epitaxy is demonstrated. Film growth sequences for nucleation of Ga2O3 on (100)‐ and (111)‐oriented Si substrates are developed, and the influence of crucial growth parameters is systematically investigated, namely, substrate temperature, oxygen flow rate, and plasma power on the functional properties of the PDs. The PDs show an ultra‐high responsivity of 837 A W−1 and a fast ON/OFF time below 4 ms at −5 V. In addition, they display strong rectifying properties and a sharp cutoff below 280 nm with the average responsivities between 10 and 80 A W−1, a detectivity on the order of 1010 Jones, and rise/fall times between 4 and 500 ms. High photoconductive gain is likely to be due to the mid‐bandgap donor/acceptor defect levels, including oxygen vacancies in the form of self‐trapped holes. It is demonstrated that these defect levels can be modified by controlling the growth conditions, thereby allowing for tailoring of the PD characteristics for specific applications. The methodology represents a cost‐effective solution over homoepitaxial approaches, with characteristics that meet or exceed those reported previously, offering new possibilities for on‐wafer integration with Si opto‐electronics.
Leaf‐economic strategies across the Eocene–Oligocene transition correlate with dry season precipitation and paleoelevation
Authors: Butrim Matthew J. , Royer Dana L.
Published: December 2020

PREMISE

The Eocene–Oligocene transition (EOT; 34–33 Ma) was marked by global cooling and increased seasonality and aridity, leading to a shift in North American floras from subtropical forests to deciduous hardwood forests similar to today. This shift is well documented taxonomically and biogeographically, but its ecological nature is less known.

METHODS

Using the relationship between petiole cross‐sectional area and leaf mass, we estimated leaf dry mass per area (LMA), a functional trait tied to plant resource investment and expenditure, at 22 western North American sites spanning the EOT to determine how the broad restructuring of vegetation during this time was reflected in leaf economics.

RESULTS

There was no overall shift in LMA between pre‐EOT and post‐EOT floras; instead, changes in LMA across sites were mostly driven by a negative correlation with dry‐season precipitation and a positive correlation with paleoelevation. These patterns held for both whole sites and subsets of sites containing taxa with similar biogeographical histories (taxa that persisted in the highlands across the EOT or that migrated to the lowlands) and are consistent with most observations in extant floras.

CONCLUSIONS

Our data provide a geological context for understanding environmentally paced changes in leaf‐economic strategies, particularly linking leaf economic strategies to dry‐season precipitation and paleoelevation.
Paired Copper Monomers in Zeolite Omega: The Active Site for Methane‐to‐Methanol Conversion
Authors: Knorpp Amy J. , Pinar Ana B. , Baerlocher Christian , McCusker Lynne B. , Casati Nicola , Newton Mark A. , Checchia Stefano , Meyet Jordan , Palagin Dennis , van Bokhoven Jeroen A.
Published: December 2020

The direct conversion of methane to methanol using oxygen is a challenging but potentially rewarding pathway towards utilizing methane. By using a stepwise chemical looping approach, copper‐exchanged zeolites can convert methane to methanol, but productivity is still too low for viable implementation. However, if the nature of the active site could be elucidated, that information could be used to design more effective catalysts. By employing anomalous X‐ray powder diffraction with support from theory and other X‐ray techniques, we have derived a quantitative and spatial description of the highly selective, active copper sites in zeolite omega (Cu‐omega). This is the first comprehensive description of the structure of non‐copper‐oxo active species and will provide a pivotal model for future development for materials for methane to methanol conversion.
Site Sensitivity of Interfacial Charge Transfer and Photocatalytic Efficiency in Photocatalysis: Methanol Oxidation on Anatase TiO2 Nanocrystals
Authors: Fu Cong , Li Fei , Zhang Jiachen , Li Dan , Qian Kun , Liu Yong , Tang Junwang , Fan Fengtao , Zhang Qun , Gong Xue‐Qing , Huang Weixin
Published: December 2020

Photocatalytic oxidation of methanol on various anatase TiO2 nanocrystals was studied by in situ and time‐resolved characterizations and DFT calculations. Surface site and resulting surface adsorbates affect the surface band bending/bulk‐to‐surface charge migration processes and interfacial electronic structure/interfacial charge transfer processes. TiO2 nanocrystals predominantly enclosed by the {001} facets expose a high density of reactive fourfold‐coordinated Ti sites (Ti4c) at which CH3OH molecules dissociate to form the CH3O adsorbate (CH3O(a)Ti4c). CH3O(a)Ti4c localized density of states are almost at the valence band maximum of TiO2 surface, facilitating the interfacial hole transfer process; CH3O(a)Ti4c with a high coverage promotes upward surface band bending, facilitating bulk‐to‐surface hole migration. CH3O(a)Ti4c exhibits the highest photocatalytic oxidation rate constant. TiO2 nanocrystals enclosed by the {001} facets are most active in photocatalytic methanol oxidation.
Nickel‐Catalyzed Electrochemical C(sp3)−C(sp2) Cross‐Coupling Reactions of Benzyl Trifluoroborate and Organic Halides**
Authors: Luo Jian , Hu Bo , Wu Wenda , Hu Maowei , Liu T. Leo
Published: December 2020

Reported here is the redox neutral electrochemical C(sp2)−C(sp3) cross‐coupling reaction of bench‐stable aryl halides or β‐bromostyrene (electrophiles) and benzylic trifluoroborates (nucleophiles) using nonprecious, bench‐stable NiCl2⋅glyme/polypyridine catalysts in an undivided cell configuration under ambient conditions. The broad reaction scope and good yields of the Ni‐catalyzed electrochemical coupling reactions were confirmed by 50 examples of aryl/β‐styrenyl chloride/bromide and benzylic trifluoroborates. Potential applications were demonstrated by electrosynthesis and late‐stage functionalization of pharmaceuticals and natural amino acid modification, and three reactions were run on gram‐scale in a flow‐cell electrolyzer. The electrochemical C−C cross‐coupling reactions proceed through an unconventional radical transmetalation mechanism. This method is highly productive and expected to find wide‐spread applications in organic synthesis.
Bis‐Cyclooctatetraenyl Thulium(II): Highly Reducing Lanthanide Sandwich Single‐Molecule Magnets
Authors: Moutet Jules , Schleinitz Jules , La Droitte Léo , Tricoire Maxime , Pointillart Fabrice , Gendron Frédéric , Simler Thomas , Clavaguéra Carine , Le Guennic Boris , Cador Olivier , Nocton Grégory
Published: December 2020

Divalent lanthanide organometallics are well‐known highly reducing compounds usually used for single electron transfer reactivity and small molecule activation. Thus, their very reactive nature prevented for many years the study of their physical properties, such as magnetic studies on a reliable basis. Herein, the access to rare organometallic sandwich compounds of TmII with the cyclooctatetraenyl (Cot) ligand impacts on the use of divalent organolanthanide compounds as an additional strategy for the design of performing Single Molecule Magnets (SMM). The first divalent thulium sandwich complex with f13 configuration behaving as a single‐molecule magnet in absence of DC field is highlighted.
Titanium Germylidenes
Authors: Lee Vladimir Ya. , Sakai Ryo , Takanashi Kazunori , Gapurenko Olga A. , Minyaev Ruslan M. , Gornitzka Heinz , Sekiguchi Akira
Published: December 2020

Two novel 18‐electron titanium germylene complexes, Cp2Ti(L)=Ge[Si3(SiMetBu2)4] 3 b (L=Me3P) and 3 c (L=XylNC), were synthesized, isolated, and structurally characterized. The length of the titanium‐germanium bonds of 2.5387(3) Å and 2.5276(3) Å (in 3 b and 3 c, respectively) well match those expected for the double bond, which was further supported by the DFT study. Based on their structural characteristics, as well as their atomic charges calculations which revealed Ti(δ+)=Ge(δ−) bond polarization, both 3 b and 3 c are classified as the Schrock‐type titanium germylidenes, as the germanium analogues of the widely known titanium alkylidenes. By contrast, germylene complexes of the group 6 metals 8 a (M=Mo) and 8 b (M=W) are better described as Fischer‐type germylene complexes.
Patients as partners in readiness for COVID‐19: using ‘live simulation’ to implement infection prevention and control procedures in the maternity operating theatre
Authors: Cegielski D. , Darling C. , Noor C. , Shelton C .L. , Parry Z.
Published: December 2020

Insitu simulation can be used to improve care within a particular setting and has specific value in developing and testing guidelines and procedures. However, it can be challenging to undertake simulation when clinical work is ongoing. Responding to the need to develop infection prevention and control procedures for coronavirus disease 2019 in the obstetric operating theatre, we asked three patients who required operative intervention to consent to be managed according to preliminary standard operating procedures as if they were severe acute respiratory syndrome‐coronavirus‐2 positive. With this method, we were able to run scenarios in real‐time without interrupting clinical work. As well as allowing us to develop and refine procedures, these ‘live simulations’ provided staff training and highlighted system problems that needed to be addressed as the first wave of the pandemic approached. In this case series, we describe our procedure for live simulation, report the learning points that this approach yielded, present the feedback from patient participants and reflect on the ethical implications of this technique.
Association between Autism Spectrum Disorder and Food Allergy: A Systematic Review and Meta‐analysis
Authors: Wang Lei , Shen Weimin , Yao Hao , Zheng Rongying , Chen Wenshu , Zhang Weixi
Published: December 2020

Autism spectrum disorder (ASD) and food allergy (FA) are global public health problems. Several studies have explored the association between ASD and FA, but the conclusions were inconsistent. The aim of this review was to evaluate the relationship between ASD and FA. The PubMed, Embase, and Web of Science databases were searched from inception to February 2, 2020. Studies investigating the association between ASD and FA were included. A random effects model was used to pool risk estimates. Subgroup analysis and sensitivity analysis were used to explore the potential sources of heterogeneity. Fifteen studies with a total of 293,130 participants were included in this review. The pooled prevalence of FA in individuals with ASD was 13% (95% confidence interval (CI): 0.10–0.17), while the pooled prevalence of FA in controls was 5% (95% CI: 0.04–0.07). The pooled odds ratio (OR) for FA in individuals with ASD was 2.45 (95% CI: 2.25–2.67). One study examined the prevalence of ASD in participants with FA. The prevalence of ASD in individuals with FA was 3.5% (95% CI: 0.029–0.042), while the prevalence of ASD in the control group was 1.6% (95% CI: 0.015–0.017). Five study examined the OR of ASD in participants with FA. The OR for ASD in individuals with FA was 1.95 (95% CI: 1.73–2.19). The results of this systematic review and meta‐analysis seem to reveal a significant association between ASD and FA.

Lay Summary

This systematic review and meta‐analysis evaluate the relationship between ASD and FA. We found that the prevalence of FA was higher in participants with ASD than in controls and participants with ASD were at risk of developing FA and the prevalence of ASD was higher in participants with FA than in controls and participants with FA were at risk of developing ASD. Additional research such as a prospective cohort study is required to better understand the relationship between ASD and FA.
PTPN6 promotes chemosensitivity of colorectal cancer cells via inhibiting the SP1/MAPK signalling pathway
Authors: Fang Huilong , Ma Wei , Guo Xuli , Wang Junjie
Published: December 2020

The abnormal expression of protein tyrosine phosphatase nonreceptor type 6 (PTPN6) has been proved to be associated with the progression of colorectal cancer. However, its role in chemosensitivity and related molecular mechanism have not been clarified. It has been reported that PTPN6 was down‐regulated in colorectal cancer cells compared with the normal colorectal cells. To evaluate the effects of PTPN6 on the proliferation and survival of colorectal cancer cells, PTPN6 was overexpressed in colorectal cancer cells in the present study. We found that cell proliferation and viability were both decreased after overexpression of PTPN6. The IC50 of 5‐Fu against colorectal cells was also declined in PTPN6 transfected cells. And further, we verified that PTPN6 could down‐regulate the expression of P‐gp and MRP‐1. Moreover, SP1 was the target protein of PTPN6 predicated by ChIPBase software and confirmed through Co‐immunoprecipitation assay and it was negatively regulated by PTPN6. To further verify the effect of SP1 on chemoresistance, SP1 was overexpressed. SP1 overexpression enhanced the drug‐resistance to 5‐Fu and abrogated the effects of PTPN6 upregulation on 5‐Fu resistance. All the above changes were associated with the down‐regulation of proteins related to MAPK signalling pathway, such as phosphorylation of extracellular regulated protein kinases (ERK) and p38. In summary, PTPN6 promoted chemosensitivity of colorectal cancer cells by targeting SP1 and inhibiting the activation of MAPK signalling pathway.

Significance of the study

It has been demonstrated that the abnormal expression of PTPN6 was related to the progression of colorectal cancer. However, the chemosensitivity of PTPN6 and its molecular mechanisms were still unclear. Here, we identified that PTPN6 was down‐regulated in colorectal cancer cells. Moreover, PTPN6 overexpression not only reduced cell proliferation and viability, but decreased the resistance of colorectal cells to 5‐Fu. In our research, we found that the SP1 was the target protein of PTPN6 and it was negatively regulated by PTPN6. In addition, SP1 could increase the resistance of colorectal cells to 5‐Fu. Molecular mechanism studies have shown that PTPN6 promoted the chemosensitivity of colorectal cancer cells by inhibiting the activation of MAPK signalling pathway.
Fatal rupture of pulmonary artery pseudoaneurysm after thoracic radiation therapy against lung squamous cell carcinoma: A case report and literature review
Authors: Fukuda Yosuke , Homma Tetsuya , Uno Tomoki , Murata Yasunori , Suzuki Shintaro , Shiozawa Eisuke , Takimoto Masafumi , Sagara Hironori
Published: December 2020

Pulmonary artery pseudoaneurysm is a rare but fatal condition. It has been associated with lung cancer, abscesses, and radiation therapy. Identification in patients with hemoptysis is critical, and timely interventional therapy is warranted.
Selective C−O Bond Cleavage of Bio‐Based Organic Acids over Palladium Promoted MoOx/TiO2
Authors: Nacy Ayad , de Lima e Freitas Lucas Freitas , Albarracín‐Suazo Sandra , Ruiz‐Valentín Génesis , Roberts Charles A. , Nikolla Eranda , Pagán‐Torres Yomaira J.
Published: December 2020

Hydrodeoxygenation chemistries play a key role in the upgrading of biomass‐derived feedstocks. Among these, the removal of targeted hydroxyl groups through selective C−O bond cleavage from molecules containing multiple functionalities over heterogeneous catalysts has shown to be a challenge. Herein, we report a highly selective and stable heterogeneous catalyst for hydrodeoxygenation of tartaric acid to succinic acid. The catalyst consists of reduced Mo5+ centers promoted by palladium, which facilitate selective C−O bond cleavage, while leaving intact carboxylic acid end groups. Stable catalytic performance over multiple cycles is demonstrated. This catalytic system opens up opportunities for selective processing of biomass‐derived sugar acids with a high degree of chemical functionality.
Spontaneously Forming Oxide Layer of High Entropy Alloy Nanoparticles Deposited on Porous Carbons for Supercapacitors
Authors: Shen Enhui , Song Xuehua , Chen Qibin , Zheng Mengmeng , Bian Jianqing , Liu Honglai
Published: December 2020

High‐entropy alloy nanoparticles with a thin metal oxide layer, deposited onto hypercrosslinked polymer‐based carbon (HCPC), were synthesized through the adsorption of five metal ions in the hypercrosslinked polymers and subsequent in situ reduction of such ions (Fe2+, Co2+, Ni2+, Cu2+ and Sn2+), followed by a carbonization process. The as‐prepared composites exhibit an excellent specific capacitance (495.4 F/g at 0.5 A/g in 1 M KOH), a superior cycling stability (94.7 % of initial capacitance after 15000 cycles at 10 A/g), and ultrafast charge transport kinetics (88.9 % fast kinetic capacitance at 200 mV/s). These excellent electrochemical behaviors are attributed to the pseudocapacitance of the metal oxide layer spontaneously formed on the outermost surface of the composite, having a thickness at the nanometer scale. Such findings suggest that this simple strategy, combining multimetallic nanoparticles with porous carbon materials, has promising potential to improve specific capacitance and paves the way to develop both the preparation of high‐entropy alloys and supercapacitors with improved performance.
Synthesis and Evaluation of Non‐Hydrolyzable Phospho‐Lysine Peptide Mimics
Authors: Hauser Anett , Poulou Eleftheria , Müller Fabian , Schmieder Peter , Hackenberger Christian P. R.
Published: December 2020

Invited for the cover of this issue is the group of Christian P. R. Hackenberger at the Leibniz‐Forschungsinstitut für Molekulare Pharmakologie and the Humboldt‐Universität zu Berlin. The image depicts a phospho‐lysine peptide mimic which reflects a phosphorylated lysine but is not identical. Read the full text of the article at 10.1002/chem.202003947.
Plastik‐Index PLIX macht Verpackungen vergleichbar
Authors: van den Adel Friederike , Scagnetti Carla , Lorenz Manuel , Krieg Hannes , Albrecht Stefan
Published: December 2020

Der Plastik‐Index (PLIX) bietet Konsumierenden und Unternehmen ein verständliches Instrument zur Bewertung von Kunststoffverpackungen und zum Vergleich von Kunststoffverpackungen. Der PLIX befähigt Konsumierende, ihren Verpackungsverbrauch zu reduzieren und Unternehmen in Handel und Logistik, ihren gesamten ökologischen Fußabdruck zu minimieren. Die Bewertungskriterien für den PLIX sind die Verpackungsmenge, die Rezyklierfähigkeit und deren Umweltwirkung; die daraus resultierende Bewertung wird in einem „best case“ bis „worst case“ Szenario dargestellt. Unter Berücksichtigung des Lebenszyklusgedankens wird die Verpackung von „Cradle to Gate“, also vom Rohstoffabbau bis zum Point of Sale im Einzelhandel berücksichtigt. In der vorliegenden Fallstudie dient der PLIX als Instrument zum Vergleich verschiedener Verpackungen innerhalb der Produktgruppe Tomaten. Grundsätzlich ist der PLIX jedoch auch für Anwendungsfälle außerhalb des Lebensmittelbereiches geeignet.