bluuebunny/crossref_metadata_2025 huggingface dataset:
Diversity and antimicrobial activity of marine nudibranch associated bacteria against tropical human skin pathogens
Authors: Sabdono Agus , Radjasa Ocky , Trianto Agus , Korshunova Tatiana , Martynov Alexander , Sibero Mada
Published: September 2022

Background: Skin disease is the fourth most common disease among all diseases. The number of cases of skin diseases continues to increase, and people commonly use antibiotics to treat these diseases. Nevertheless, overuse of antibiotics can increase the resistance of these pathogens. Hence, the study of novel antibiotic compounds against multi-drug resistant (MDR) skin pathogens is urgently needed.

Methods: This study describes the antimicrobial diversity of bacteria associated with three species of marine nudibranchs (Jorunna funebris, Gymnodoris rubropapulosa, and Glossodoris atromarginata) sampled from Jepara coastal waters, the North Java Sea in August 2020. A total of 115 bacterial strains were selected for their prospective antipathogenic compounds against the pathogens Cutibacterium acnes, Staphylococcus aureus, Candida albicans, and Malassezia furfur.

Results: A total of 24 bacterial isolates (20.87%) exhibited antimicrobial activity against the pathogens that were selected and molecularly identified. Analyses of the gene of 16S rRNA discovered that these 24 isolates were associated with 11 genera of the phyla Firmicutes, Proteobacteria, and Actinobacteria, including Bacillus as the dominant genus, followed by Streptomyces, Gordonia, Salinicola, Thalassospira, Halomonas, Dietzia, Brevibacterium, Paracoccus, Pseudovibrio, Pseudoalteromonas, and Pseudomonas. None of the 24 antimicrobial bacterial strains possessed type-1 polyketide synthases (PKS-I). One strain possessed type II polyketide synthases (PKS-II), and five strains possessed non-ribosomal peptide synthetase (NRPS) genes. The amounts of bacterial genus and strains in the three nudibranchs differed significantly, as did the proportions of antimicrobial strains in each nudibranch species. The antibacterial strains isolated from G. atromarginata were the highest number (62.5%), followed by J. funebris (20.8%) and G. rubropapulosa (16.7%).

Conclusions: These results demonstrate that nudibranch species harbor prominent and varied communities of bacteria and reveal that many nudibranch-associated bacteria have the potential for the advancement of broad-spectrum antibiotics.
Case Report: Interstitial-intralesional laser therapy and laser-assisted new attachment procedure for the treatment of alveolar bone loss provoked by an aggressive pyogenic granuloma
Authors: Akkarapatum Anon , Klanrit Poramaporn , Sattayut Sajee
Published: September 2022

Background: A pyogenic granuloma (PG) is a common benign vascular lesion found in the oral cavity. The gold standard treatment of this lesion, comprising surgical excision and the elimination of etiological factors, cannot avoid tooth loss in the case of an aggressive pyogenic granuloma. Because of the prominent properties of 980 nm and 635 nm diode lasers in photocoagulation and photobiomodulation, we applied these wavelengths in the treatment of a large pyogenic granuloma with alveolar bone loss.

Case presentation: Our objective was to use a combination of interstitial-intralesional laser therapy, photocoagulation and laser-assisted new attachment procedure (LANAP) to preserve the teeth and periodontal tissue in a case of an aggressive pyogenic granuloma.

Results: The patient was a 13-year-old Thai male with a pyogenic granuloma involving the interdental papilla and lingual gingiva of the lower left first and second molars. The teeth were also displaced by the lesion. After treatment with three sessions of photocoagulation, three sessions of interstitial-intralesional laser therapy and two sessions of LANAP, the lesion was completely resolved. The periodontal status of the teeth was improved at the six-month follow-up.

Conclusion: The combination of interstitial-intralesional laser therapy, photocoagulation and LANAP was able to treat an aggressive pyogenic granuloma with tooth preservation.
Public perceptions and interactions with UK COVID-19 Test, Trace and Isolate policies, and implications for pandemic infectious disease modelling
Authors: Marshall Guy C. , Skeva Rigina , Jay Caroline , Silva Miguel E. P. , Fyles Martyn , House Thomas , Davis Emma L. , Pi Li , Medley Graham F. , Quilty Billy J. , Dyson Louise , Yardley Lucy , Fearon Elizabeth
Published: September 2022

Background

The efforts to contain SARS-CoV-2 and reduce the impact of the COVID-19 pandemic have been supported by Test, Trace and Isolate (TTI) systems in many settings, including the United Kingdom. Mathematical models of transmission and TTI interventions, used to inform design and policy choices, make assumptions about the public’s behaviour in the context of a rapidly unfolding and changeable emergency. This study investigates public perceptions and interactions with UK TTI policy in July 2021, assesses them against how TTI processes are conceptualised and represented in models, and then interprets the findings with modellers who have been contributing evidence to TTI policy.

Methods

20 members of the public recruited via social media were interviewed for one hour about their perceptions and interactions with the UK TTI system. Thematic analysis identified key themes, which were then presented back to a workshop of pandemic infectious disease modellers who assessed these findings against assumptions made in TTI intervention modelling. Workshop members co-drafted this report.

Results

Themes included education about SARS-CoV-2, perceived risks, trust, mental health and practical concerns. Findings covered testing practices, including the uses of and trust in different types of testing, and the challenges of testing and isolating faced by different demographic groups. This information was judged as consequential to the modelling process, from guiding the selection of research questions, influencing choice of model structure, informing parameter ranges and validating or challenging assumptions, to highlighting where model assumptions are reasonable or where their poor reflection of practice might lead to uninformative results.

Conclusions

We conclude that deeper engagement with members of the public should be integrated at regular stages of public health intervention modelling.
Case Report: Account of chickenpox progression over 10 days
Authors: Bereda Gudisa
Published: September 2022

Chickenpox is an extremely contagious disease; caused by the varicella-zoster virus primary infection. A 27-year-old adult Black African male health care worker presented with severe headache, intermittent weakness and inability to walk, intermittent nausea, fever, nocturnal polydipsia, shortness of breath, itching, pruritus (intensely pruritic erythematous macules), lesions with pus on the skin, sleep disturbances, and nightmares for two days. The most commonly occurring symptom of chickenpox is a vesicular rash that appears on the scalp, back and front of the neck, face and scapulae, and then disseminates distally to the limbs. In this case report, the patient face, neck and scapulae were the most infected areas of the body and the rest of the body except the legs, hands, genital areas and buttocks, were also highly infected. Acyclovir 800 mg orally, five times a day was given for ten days to cure chickenpox infection because acyclovir inhibits the replication of the varicella zoster virus, and has the ability to eradicate varicella zoster virus and relieve the symptoms more readily.
Anticancer potential of turmeric (Curcuma longa) ethanol extract and prediction of its mechanism through the Akt1 pathway
Authors: Widyananda Muhammad Hermawan , Puspitarini Sapti , Rohim Abdul , Khairunnisa Fika Agalia , Jatmiko Yoga Dwi , Masruri Masruri , Widodo Nashi
Published: September 2022

Background: Turmeric (Curcuma longa) has high potential as a traditional anticancer drug. This study aimed to analyze the anticancer activity of turmeric ethanol extract on T47D cells and examine the interaction of Akt1 protein with compounds contained in turmeric.

Methods: The cytotoxicity assay was conducted using WST-1 reagents. Apoptosis assay used annexin V-PI, whereas cell cycle assay used PI, and then the results were analyzed using a flow cytometer. LC-HRMS analysis was conducted to identify the active compounds. Docking between Akt1 and ligands was performed using Autodock 4.2 software. Molecular dynamics simulations were conducted using YASARA with a time parameter of 20 ns, pH 7.4, and 37°C.

Results: The extract had a strong toxicity on T47D cells (cytotoxicity IC50 value: 26.36 ± 1.55 µg/mL). The extract induced apoptosis of T47D cells at the IC50 dose (~30% cells) and induced the cell cycle arrest in G1 phase. Curcumin, 2-hydroxycinnamic acid and caryophyllene oxide had lower binding energy into Akt1 than AZD5363 used as a positive control. Curcumin, Ar-turmerone, and α-curcumene bind in the ATP binding pocket of Akt1, so the compounds have a high potential to be an ATP-competitive Akt1 inhibitors. The interaction of Akt1 with the compound contained in turmeric had an RMSD backbone value that was more stable than that of ATP and AZD5363. Root-mean-square fluctuation values indicated that amino acid residues that had an essential role in ligand binding sites were stable during simulation.

Conclusions: The turmeric ethanol extract had a potential anti-cancer effect by inducing apoptosis and inhibiting cell cycle progression on T47D cells. The docking analysis showed that the active compounds of the extract, such as curcumin, Ar-turmerone, caryophyllene oxide, and α-curcumene, were able to bind into the ATP binding pocket of Akt1 that might inhibit the protein activity and induce cell cycle arrest.
Case Article—Blending Statistics, Optimization, and Simulation in a Multiphase Case
Authors: Gorman Michael Francis
Published: September 2022

This case integrates three different methodologies over a four-part sequence on a problem that mirrors a real-world, published project. Students apply statistics, integer optimization, and simulation analysis toward solving the job assignment problem. The case features four parts: (1) operating cost and runtime estimation via regression, (2) mixed integer optimization analysis of a baseline and two scenarios, (3) simulation of the recommended solution under uncertainty, and (4) reoptimization under uncertainty. The case has been implemented over a one- to four-week period with upper level MBA or masters in analytics students. The case has received very positive feedback.

History: This paper has been accepted for the INFORMS Transactions on Education Special Section on Cases Based on Real-World Projects from the INFORMS Journal on Applied Analytics.

Supplemental Material: The supplemental material is available at https://doi.org/10.1287/ited.2022.0278ca . The Teaching Note and data files are available at https://www.informs.org/Publications/Subscribe/Access-Restricted-Materials .
A Real Utopia Under What Conditions? The Economic and Social Benefits of Workplace Democracy in Knowledge-Intensive Industries
Authors: Young-Hyman Trevor , Magne Nathalie , Kruse Douglas
Published: September 2022

Given consistent evidence of its social benefits but questions about its market viability, this paper examines the conditions under which workplace democracy can be understood as a “real utopia”; a viable form of organization that is both economically productive and socially welfare enhancing. Conceptualizing democratic firms as organizations with formally distributed authority and collectivist norms, we argue that democratic firms will operate more productively in knowledge intensive industries, compared with conventional firms in the same industries, because they give authority to those with relevant knowledge and encourage intrafirm information sharing. Next, focusing on intrafirm wage inequality as a key social welfare outcome, we argue that knowledge-intensive sectors are also settings where the benefits of workplace democracy are likely to be greater. Knowledge intensive industries tend to generate greater intrafirm inequality through the adoption of market-based employment policies and reliance on unique expertise, yet the formal structure and collectivist norms of democratic firms are likely to limit these mechanisms of inequality, generating inequality reductions. We test these hypotheses with longitudinal linked employer-employee data from French cooperatives and conventional firms, including firms that shift organizational structures over time. We find robust support for our hypothesis about economic performance and moderate support for our hypothesis about social performance.

Funding: This research has been generously supported by the Berg Center for Ethics, the Katz International Business Center, and the Bill Nobles Fellowship, as well as a public grant overseen by the French National Research Agency (ANR) as part of the “Investissements d’Avenir” program [Reference ANR-10-EQPX-17-Centre d’accès sécurisé aux données].

Supplemental Material: The online appendix is available at https://doi.org/10.1287/orsc.2022.1622 .
Creating a sensory garden
Authors: Hewson Claire
Published: September 2022

A sensory garden is an inclusive space that stimulates learning for all children and promotes a sense of wellbeing. Here we share reasons why sensory experiences are so important and how you can create a sensory garden.
Calving pen management
Authors: Robertson Jamie F , Cavill Rebecca S
Published: September 2022

Calving is one of the most stressful events to occur during the production cycle in dairy cows, and the environment in which this occurs can significantly impact the health of the neonatal calf. The incidence of enteric and respiratory disease in young calves can be reduced by managing this environment better, limiting contamination and resultant infection pressure. The environment in which calves were managed from birth onwards was observed and scored on 66 dairy farms in Northern Ireland over a 3 week period. Assessments were made on hygiene factors such as stocking density, presence of sick cows, bedding frequency, cleaning frequency, ease of cleaning and hygiene scoring. This study highlights that, despite the clear need for managing hygiene around the time of birth, hygiene in the calving pen is often an area that producers do not focus on improving in order to efficiently rear a healthy, productive and robust dairy cow.
Time to engage sheep farmers with Medicine Hub
Authors: Nevel Amanda
Published: September 2022

Since its quiet launch in October 2021, Medicine Hub has been populated with farming accounts predominantly via practice management software programmes and bulk data holders, with a skew towards dairy. However, now is the perfect time to address this by engaging with sheep farmer clients; Animal Health and Welfare Pathway visits represent an ideal opportunity to open discussions. Meanwhile, capitalising on trading advantages which may come about as a result of antibiotic use recording could be especially relevant for sheep producers. Although the sector is typically a low user of antibiotics, this remains important information to gather for the national picture.
ENCARCERAMENTO E AS ESTRUTURAS SOCIOECONÔMICAS QUE CRISTALIZAM O SISTEMA
Authors: Nunes Lucas Ribeiro Laudano
Published: September 2022

O presente artigo tem por escopo discutir a respeito do encarceramento e as estruturas socioeconômicas que exercem papel fundamental na conservação do sistema. Trata-se de um estudo documental desenvolvido através da análise de livros, textos, vídeos e filme. A Guerra às Drogas, o neoliberalismo e as outras racionalizações adquiridas com o tempo avançam no propósito de manterem o poder e o desenvolvimento sob controle de poucos, como Max Weber mostrou nos seus estudos. Nesse sentido, a cristalização do sistema é fundamentada pelos elementos trazidos na discussão, e são apresentadas soluções para combater o conservadorismo, a fim de um sistema com pautas mais justas e de assistência aos desfavorecidos.
O PRINCÍPIO DA DIGNIDADE HUMANA E O DISCURSO DE ÓDIO SOB A PERSPECTIVA DO FORTALECIMENTO DO ESTADO PENAL
Authors: Melo Iasmin Alves Ferreira
Published: September 2022

A construção social e a caminhada histórica do conceito de dignidade humana foi traçada de modo conflituoso, estando ligada, em seu âmago, ao sistema penal. Na conjuntura hodierna, salienta-se a presença simultânea de avanços e retrocessos na área criminal; é nesse contexto em que se discute a presença marcante do discurso de ódio, fenômeno cuja difusão através da mídia figura como combustível para o enrijecimento do Direito Penal. Assim, propõe-se analisar o fortalecimento do Estado penal que é intimamente acompanhado da violação de princípios constitucionais, como a dignidade humana, que regem, ou deveriam reger, o ordenamento pátrio.
Ranges of pregnancy preferences and contraceptive use: Results from a population‐based survey in the southeast United States
Authors: Rocca Corinne H. , Smith Michael G. , Hale Nathan L. , Khoury Amal J.
Published: September 2022

Context

Understanding how pregnancy preferences shape contraceptive use is essential for guiding contraceptive interventions and policies that center individuals' preferences and desires. Lack of rigorous measurement of pregnancy preferences, particularly on the population level, has been a methodologic challenge.

Methods

We investigated associations between prospective pregnancy preferences, measured with a valid instrument, the Desire to Avoid Pregnancy (DAP) scale, and contraceptive use in a representative sample of 2601 pregnancy‐capable self‐identified women, aged 18–44 years, in Alabama and South Carolina (2017–2018). We used multivariable regression with weighting to investigate how probability of modern contraceptive use, and use of different contraceptive method types, changed with increasing preference to avoid pregnancy.

Results

Desire to Avoid Pregnancy scale scores (range:0–4, 4 = greater preference to avoid pregnancy, median = 2.29, IQR: 1.57–3.14; α:0.95) were strongly associated with contraceptive use among sexually active respondents (aPR = 1.15 [1.10, 1.20]; predicted 45% using contraception among DAP = 0, 62% among DAP = 2, 86% among DAP = 4). Method types used did not differ by DAP score. The most common reasons for nonuse were concern over side effects and not wanting to use a method (32% each) among respondents with mid‐range and high DAP scores. Among those with mid‐range DAP scores, 20% reported nonuse due to not minding if pregnancy were to occur (vs. 0% among those with high DAP scores).

Conclusions

Pregnancy preferences strongly influence likelihood of contraceptive use. Providion of appropriate contraceptive care to those not explicitly desiring pregnancy must differentiate between ranges of feelings about pregnancy, perceived drawbacks to contraceptive use, and legitimate psychological and interpersonal benefits of nonuse to promote autonomy in contraceptive decision‐making.
Provision of fertility services to women in same‐sex relationships at Catholic and non‐Catholic clinics in the United States
Authors: Stein Lara Elizabeth , Goldman Kara N. , Takimoto Sarah , Neshek Barbara , Guiahi Maryam
Published: September 2022

Introduction

This study addressed deficient information on the provision of infertility care in obstetrics and gynecology clinics. We additionally evaluated the availability of these services based on clinic affiliations or stated sexual orientation.

Methodology

We performed a national cross‐sectional “mystery caller” survey of 293 general obstetrics and gynecology clinics in 2017–2018. We matched clinics identified by web‐based search engine in a 1:1 ratio by Catholic hospital affiliation, after determining number of clinics based on state‐population densities. A standard call script included questions regarding provision of infertility services, ovulation induction methods, and information about the caller's sexual orientation. We performed descriptive frequencies and compared responses based on hospital affiliations.

Results

Of the 293 clinics included, 49% were affiliated with Catholic and 17% with academic hospitals. The majority offered infertility care (85%, 248/293), and of these 97% (240/248) offered ovulation induction. Only 3% (6/240) reported they would not provide to women in same‐sex relationships. Most clinics not offering infertility evaluations (43/45, 96%) cited it was outside of their scope of care and of these 33% (15/45) did not provide information for self‐referral. Clinics affiliated with academic (aOR 0.23) or Catholic (aOR 0.34) hospitals were less likely to provide evaluations. Those with academic affiliation were more likely to provide information for self‐referral (aOR 19.2).

Discussion

Most general obstetrics and gynecology practices offered appointments for infertility evaluation and ovulation induction. Clinics rarely denied services to women reporting a same‐sex partnership, regardless of hospital affiliation. These findings provide reassurance to same‐sex couples seeking fertility care.
Transverse-pumping approach for a powerful single-mode Ti:sapphire laser for near infrared lidar applications
Authors: Vogelmann Hannes , Speidel Johannes , Perfahl Matthias , Trickl Thomas
Published: September 2022

We present a design of a transversely pumped and powerful Ti:sapphire
laser, suitable for laser remote sensing in the near infrared (NIR)
spectrum. Examining multiple pump configurations revealed that
transversal pumping of Ti:sapphire crystals with a Nd:YAG laser
(532 nm) from one or two sides yields maximum output power. Together
with an optimized bow-tie resonator setup, we were able to extract up
to 3 W (30 mJ, 100 Hz) of narrowband NIR laser emission from a cuboid
50 mm long Ti:sapphire crystal. Beam quality and divergence were
determined as

M
x
2

=
1.1

,

M
y
2

=
1.7

,

φ
x

=
0.5

m
r
a
d

, and

φ
y

=
0.8

m
r
a
d

. The spectral purity (seeded,

P

s
e
e
d

≥
170

µ
W

) was better than 99.8%.
Additionally, we show a two-wavelength setup applicable to atmospheric
water vapor lidar. The principle performance of this theory of
operation suggests a good chance of scalability towards significantly
enhanced power of future Ti:sapphire lasers.
Tomographic imaging of carbon dioxide in the exhaust plume of large
commercial aero-engines
Authors: Upadhyay Abhishek , Lengden Michael , Enemali Godwin , Stewart George , Johnstone Walter , Wilson David , Humphries Gordon , Benoy Thomas , Black John , Chighine Andrea , Fisher Edward , Zhang Rui , Liu Chang , Polydorides Nick , Tsekenis Alex , Wright Paul , Kliment Joshua , Nilsson Johan , Feng Yutong , Archilla Victor , Rodríguez-Carmona Javier , Sánchez-Valdepeñas Jesús , Beltran Marta , Polo Valentin , Armstrong Ian , Mauchline Iain , Walsh Douglas , Johnson Mark , Bauldreay Joanna , McCann Hugh
Published: September 2022

We report here the first implementation of chemically specific imaging in the exhaust plume of a gas turbine typical of those used for propulsion in commercial aircraft. The method used is chemical species tomography (CST) and the target species is

C
O

2

, absorbing in the near-infrared at 1999.4 nm. A total of 126 beams propagate transverse to the plume axis, along 7 m paths in a coplanar geometry, to probe a central region of diameter

≈
1.5

m

. The

C
O

2

absorption spectrum is measured using tunable diode laser spectroscopy with wavelength modulation, using the second harmonic to first harmonic (2f/1f) ratio method. The engine is operated over the full range of thrust, while data are recorded in a quasi-simultaneous mode at frame rates of 1.25 and 0.3125 Hz. Various data inversion methodologies are considered and presented for image reconstruction. At all thrust levels a persistent ring structure of high

C
O

2

concentration is observed in the central region of the measurement plane, with a raised region in the middle of the plume assumed to be due to the engine’s boat tail. With its potential to target various exhaust species, the CST method outlined here offers a new approach to turbine combustion research, turbine engine development, and aviation fuel research and development.
Estimation of positioning sparsity for Sagnac correction in fiber-optic time transfer
Authors: Yu Longqiang , Shi Lei , Li Chan , Li Xuan , Wei Jiahua , Zhu Zihang , Zhou Yixiao , Meng Qingqing
Published: September 2022

The Sagnac effect is an important factor that leads to nonreciprocity in long-haul fiber-optic time and a frequency transfer system. For high-precision time transfer, correction must be performed to eliminate the time difference based on the trajectory of the path. However, the routing information may be not detailed enough to guarantee sufficient precision for Sagnac correction. Thus, nodes along the path must be surveyed with a certain sparsity. We provide a practical method for estimating the average distance of these nodes. Six simulated paths are generated to validate the method for different uncertainties.
Quantifying polarization changes induced by rotating Dove prisms and
K-mirrors
Authors: Karan Suman , Ruchi  , Mohta Pranay , Jha Anand K.
Published: September 2022

Dove prisms and K-mirrors are devices extensively used for rotating the wavefront of an
optical field. These devices have several applications, including the
measurement of orbital angular momentum, microscopy, beam steering,
and pattern recognition. However, the wavefront rotation achieved
through these devices is always accompanied by polarization changes in
the incident field, which is an undesirable feature in many of these
applications. Although the polarization changes induced by a Dove
prism have been explored to quite some extent, no such study is
available for a K-mirror. In this paper, we theoretically and
experimentally investigate polarization changes induced in the
transmitted field by a rotating K-mirror. For quantifying such
polarization changes, we define a quantity, mean polarization change

D

, which ranges from 0 to

π

. We find that K-mirrors can reduce

D

to about

0.03
π

for any incident state of
polarization; however, reducing

D

to the same extent with a Dove prism
is practically unviable. Therefore, K-mirrors are better alternatives
to Dove prisms in applications in which the polarization changes
accompanying wavefront rotation need to be minimum.
Full-duplex transmission without an uplink light source for a millimeter-wave radio over a free-space optical system
Authors: Zhang Shuai , Zhao Lun , Song Song , Guo Lei , Liu Yejun
Published: September 2022

The radio over free-space optical (RoFSO) system is a promising alternative technique for mobile fronthaul networks such as aerial base stations where fiber link is unavailable to deploy. However, the full-duplex transmission imposes challenges on the design of the RoFSO system due to the additional structural complexity when ease-of-installation is a mandatory request. The interplay between the uplink and downlink for a simplified structure has been less investigated in related works. In this paper, we propose a full-duplex RoFSO transmission system structure in which the uplink light source is physically saved. The optical center carrier of the double-sideband (DSB) modulated signal in the downlink is extracted as the light source for the uplink, and thus the system complexity is reduced. In order to mitigate the permanence degradation of uplink transmission due to the attenuated light source, channel estimation and power pre-compensation are implemented without additional training symbols by utilizing the characteristics of the channel correlation between uplink and downlink and the information independence of optical center carrier in the DSB. The proposed channel estimation algorithm is verified theoretically and experimentally. The results show that the difference between uplink and downlink channel attenuation is

−
0.7

d
B

. In case of the excessive power compensation and the resulting effects, a power control mechanism is introduced to the power pre-compensation. By using the power pre-compensation mechanism, the bit error rate (BER) can reach

1.58
×

10

−
3

and

3.8
×

10

−
3

, respectively, under the channel conditions of medium turbulence and weak turbulence. Owing to the power control mechanism, the power saving rates of downlink and uplink are up to 78% and 67%.
Method to improve the localization accuracy and contrast recovery of lesions in separately acquired X-ray and diffuse optical tomographic breast imaging
Authors: Muldoon Ailis , Kabeer Aiza , Cormier Jayne , Saksena Mansi A. , Fang Qianqian , Carp Stefan A. , Deng Bin
Published: September 2022

Near-infrared diffuse optical tomography (DOT) has the potential to improve the accuracy of breast cancer diagnosis and aid in monitoring the response of breast tumors to chemotherapy by providing hemoglobin-based functional imaging. The use of structural lesion priors derived from clinical breast imaging methods, such as mammography, can improve recovery of tumor optical contrast; however, accurate lesion prior placement is essential to take full advantage of prior-guided DOT image reconstruction. Simultaneous optical and anatomical imaging may not always be possible or desired, which can make the accurate registration of the lesion prior challenging. In this paper, we present a three-step lesion prior scanning approach to facilitate improved accuracy in lesion localization based on the optical contrast quantified by the total hemoglobin concentration (HbT) for non-simultaneous multimodal DOT and digital breast tomosynthesis (DBT) imaging. In three challenging breast cancer patient cases, where no clear optical contrast was present initially, we have demonstrated consistent improvement in the recovered HbT lesion contrast by utilizing this method.
Generation of Backscattered X-Rays within an FEL Oscillator for Coronary Angiography*
Authors: Stein William E. , Newnam Brian E. , Lumpkin Alex H.
Published: September 2022

X-rays produced within an infrared free-electron laser (FEL) and imaged with a gated, intensified television camera may provide an inexpensive alternative to the use of synchrotrons for transvenous coronary angiography. The energy of these x-rays is dependent on the electron energy that can be controlled electronically. Variation of the x-ray energy will allow radiography above and below the K-edge of a number of elements. Image enhancement can be accomplished by digital subtraction of the radiographs. The x-ray intensities based on photon and electron intracavity powers in the operating Los Alamos 10-μm FEL compare favorably with those obtained from larger and much more expensive synchrotrons and electron storage rings. The FEL x-ray source and gated television camera can be synchronized with different phases of breathing and cardiac motion to allow the study of the heart and blood vessels at various stages of these motions.
Experiments on the Electronic and Geometric Structure of Molecules and Clusters Using XUV Free Electron Lasers
Authors: Eberhardt Wolfgang
Published: September 2022

There are several types of sources for clusters or free radicals presently in existence. However, apart from mass distributions, ionization potentials, and some chemical reactivity data, very little is known so far about these new states of matter. Neither the electronic structure nor the geometric structure of the various clusters are known so far. The reason for this lack of information is the low density of clusters in the beam produced by today's sources. Nevertheless, having an intense VUV-soft x-ray FEL-based source available it will be feasible to study the electronic structure and, to some extent, the geometric structure of mass selected clusters.
Use of VUV/XUV Free-Electron Lasers in the Study of Defects in Amorphous Optical Materials
Authors: Sanders Virgil E. , Newnam Brian E.
Published: September 2022

We propose to use an intense, coherent, light source in the VUV and XUV spectral regions, such as the proposed Los Alamos free-electron laser (FEL) user facility, to study radiation-induced defects in amorphous materials. The optical materials of interest are those associated with thin-film coatings, windows, and lenses used in most UV and visible lasers. The life, reliability, and performance of these lasers may be significantly affected by the UV environment of the laser. Examples include FELs themselves which generate harmonics of the fundamental lasing wavelength far into the VUV. Other examples include most, if not all, gas lasers where the optics, particularly thin-film coatings, are exposed to the gas plasma discharge.
UV-FEL Applications in Resonance Ionization Mass Spectrometry
Authors: Nogar N. S. , Fearey B. L. , Miller C. M.
Published: September 2022

Resonance Ionization Mass Spectrometry (RIMS) is a powerful tool for elemental and isotopic analysis. This multistep laser photoionization process, when coupled with conventional mass analysis, can provide exceptional performance in detectivity, dynamic range, and discrimination against interfering species. These properties can be used to great advantage both in the analysis of conventional analytical materials1-3and in the interrogation of surface and interfacial phenomenae4. Applications at Los Alamos include high dynamic range isotope ratio measurements, ground-water tracer measurements and optical damage studies. In this report we will discuss potential applications of a Free Electron Laser for RIMS analyses, particular emphasis will be placed on coupling FEL-based photoionization with synchronized laser desorption.
Multi-step migration of optical connections to minimize disruption time in flex-grid networks
Authors: Nguyễn Tuấn Khải , Reyes Ronald Romero , Bauschert Thomas
Published: September 2022

Migration of optical connections in flex-grid networks has become increasingly necessary as the arrivals and departures of optical connection requests are more dynamic. To mitigate disruptions of existing connections during migration, former research applies the resource dependency digraph (RDD) model to allow for sequential migration of optical connections. In this paper, we argue that, in this RDD model, each connection has a quota of one migration step only and that this one-step-quota constraint can be safely lifted to accomplish even lower disruption time due to the greater degree of migration freedom. We consider the whole migration process to be composed of multiple lightpath assignment states, each of which is to be determined individually. We show that this consideration can drastically reduce disruption time and hence the ensuing service level agreement violation penalties, even when it is already minimized under the one-step-quota constraint. For that, we propose two mathematical models. The first model, namely, multi-step optical connection migration (MOCM), adopts a layer-based abstraction in which each lightpath assignment state is represented as a layer, and the transition between two consecutive layers constitutes a migration step. In the second model, namely, MOCM2, to improve the solution efficiency, we readopt the concept of RDD and integrate multiple RDDs into MOCM to further enable even larger migration freedom. This way, the transition between two consecutive layers may involve multiple so-called meta-migration steps. As a use case, the proposed approaches are applied to perform connection migration for spectrum defragmentation. The results show that our multi-step migration scheme notably reduces disruption time as compared with the one-step-quota RDD-based approaches.
Toward Interactive Holographic Video Imaging
Authors: Benton Stephen A. , Pappu Ravikanth
Published: September 2022

Electronic holographic imagingis a truly three-dimensional real-time digital imaging medium. Recent progress in holographic video has demonstrated that the crucial technologies—computation, electronic signal manipulation, and optical modulation & scanning—may be scaled up to produce larger, more interactive, full-color holographic images.
A 16x16 Vertical Cavity Surface Emitting Laser Array Module for Optical Processing and Interconnect Applications
Authors: Paananen David , Wasserbauer John , Scott Jeffrey , Brusenbach Paul , Lewis David , Simonis George
Published: September 2022

A 16x16 Vertical Cavity Surface Emitting Laser Array Module for Optical Processing and Interconnect Applications, D. Paananen, J. Wasserbauer, J. Scott, P. Brusenbach and D. Lewis, Vixel Corporation, G. Simonis, Army Research Laboratory. We integrated 16x16 VCSEL arrays onto silicon driver circuits using In/Pb solder bump bonding. Each VCSEL is randomly accessed via the silicon circuit.
Fiber-based two-wavelength heterodyne laser interferometer
Authors: Zhang Yanqi , Guzman Felipe
Published: September 2022

Displacement measuring interferometry is a crucial component in metrology applications. In this paper, we propose a fiber-based two-wavelength heterodyne interferometer as a compact and highly sensitive displacement sensor that can be used in inertial sensing applications. In the proposed design, two individual heterodyne interferometers are constructed using two different wavelengths, 1064 nm and 1055 nm; one of which measures the target displacement and the other monitors the common-mode noise in the fiber system. A narrow-bandwidth spectral filter separates the beam paths of the two interferometers, which are highly common and provide a high rejection ratio to the environmental noise. The preliminary test shows a sensitivity floor of

7.5

pm

/

Hz

at 1 Hz when tested in an enclosed chamber. We also investigated the effects of periodic errors due to imperfect spectral separation on the displacement measurement and propose algorithms to mitigate these effects.
Object recognition in optical camera communication enabled by image restoration
Authors: Guo Meitong , Zhang Pinpin , Sun Yimao , Zhang Weihua , Zhou Yingjie , Yang Yanbing
Published: September 2022

As an important branch of visible light communication (VLC), optical camera communication (OCC) has received increasing attention recently, owing to its availability and low cost of deployment by re-using cameras as VLC receivers. However, cameras on popular smartphones and/or closed-circuit television systems have their primary function for taking pictures and recognizing objects, where the recorded images with objects are inevitable to be distorted by the coded light under OCC. To this end, we propose and experimentally demonstrate an improved OCC system which is able to achieve data communication and object recognition simultaneously. Basically, we devise an image restoration (IR) scheme to repair the pixels damaged by modulated light during data transmission, and it hence provides better image input to realize object recognition. Moreover, to maintain a reasonable data rate of OCC, we also engineer an object avoidance (OA) scheme to remove the negative effect caused by the object background in OCC frame. Finally, we implement a prototype of the proposed system to verify its performance on object recognition and communication, and experimental results show that the proposed IR can bring an improvement over 37% in terms of object recognition accuracy comparing to the baseline under a data rate of 5 kbps.
Polarization-sensitive direct laser patterning of azopolymer thin films with vortex beams
Authors: Porfirev A. P. , Khonina S. N. , Khorin P. A. , Ivliev N. A.
Published: September 2022

Laser patterning of thin films of materials is widely used for the fabrication of one-, two- and three-dimensional functional nanomaterials. Using structured laser beams with a complex structure of amplitude, phase, and polarization distributions allows one to significantly simplify and speed up the procedure of manufacturing nano- and microstructures with a complex shape, such as a spiral structure. Here, we demonstrate the use of vortex laser beams with a helical wavefront for the realization of spiral mass transfer in azopolymer films. The polarization sensitivity of this material allows us to demonstrate the formation of different three-dimensional structures in the case of linearly or circularly polarized vortex beams of different orders. The presented theoretical analysis shows that the profile of the fabricated structures is defined by the structure of the longitudinal component of the incident radiation, and thus can be easily controlled with the polarization state of the radiation without the need to change the amplitude–phase structure of the beam.
Large Format GaAs Based Spatial Light Modulators and Their use in Optical Correlation Applications
Authors: Trezza J.A. , Stack R.D. , Kang K.
Published: September 2022

Spatial light modulators (SLMs) are the key component for real time electro-optical signal processing, computing, holographic optical memory storage, free space optical interconnect, information processing, and data conversion systems. We have used our SLM technology to develop several optical processing and data routing demonstration units including beam steering units and optical correlators. The later have been created with maximum speed of 600,000 128 x 128 2-D correlations per second.
Comparing and linking machine learning and semi-mechanistic models for the predictability of endemic measles dynamics
Authors: Lau Max S. Y. , Becker Alex , Madden Wyatt , Waller Lance A. , Metcalf C. Jessica E. , Grenfell Bryan T.
Published: September 2022

Measles is one the best-documented and most-mechanistically-studied non-linear infectious disease dynamical systems. However, systematic investigation into the comparative performance of traditional mechanistic models and machine learning approaches in forecasting the transmission dynamics of this pathogen are still rare. Here, we compare one of the most widely used semi-mechanistic models for measles (TSIR) with a commonly used machine learning approach (LASSO), comparing performance and limits in predicting short to long term outbreak trajectories and seasonality for both regular and less regular measles outbreaks in England and Wales (E&W) and the United States. First, our results indicate that the proposed LASSO model can efficiently use data from multiple major cities and achieve similar short-to-medium term forecasting performance to semi-mechanistic models for E&W epidemics. Second, interestingly, the LASSO model also captures annual to biennial bifurcation of measles epidemics in E&W caused by susceptible response to the late 1940s baby boom. LASSO may also outperform TSIR for predicting less-regular dynamics such as those observed in major cities in US between 1932–45. Although both approaches capture short-term forecasts, accuracy suffers for both methods as we attempt longer-term predictions in highly irregular, post-vaccination outbreaks in E&W. Finally, we illustrate that the LASSO model can both qualitatively and quantitatively reconstruct mechanistic assumptions, notably susceptible dynamics, in the TSIR model. Our results characterize the limits of predictability of infectious disease dynamics for strongly immunizing pathogens with both mechanistic and machine learning models, and identify connections between these two approaches.
Stability criteria for the consumption and exchange of essential resources
Authors: Gibbs Theo , Zhang Yifan , Miller Zachary R. , O’Dwyer James P.
Published: September 2022

Models of consumer effects on a shared resource environment have helped clarify how the interplay of consumer traits and resource supply impact stable coexistence. Recent models generalize this picture to include the exchange of resources alongside resource competition. These models exemplify the fact that although consumers shape the resource environment, the outcome of consumer interactions is context-dependent: such models can have either stable or unstable equilibria, depending on the resource supply. However, these recent models focus on a simplified version of microbial metabolism where the depletion of resources always leads to consumer growth. Here, we model an arbitrarily large system of consumers governed by Liebig’s law, where species require and deplete multiple resources, but each consumer’s growth rate is only limited by a single one of these resources. Resources that are taken up but not incorporated into new biomass are leaked back into the environment, possibly transformed by intracellular reactions, thereby tying the mismatch between depletion and growth to cross-feeding. For this set of dynamics, we show that feasible equilibria can be either stable or unstable, again depending on the resource environment. We identify special consumption and production networks which protect the community from instability when resources are scarce. Using simulations, we demonstrate that the qualitative stability patterns derived analytically apply to a broader class of network structures and resource inflow profiles, including cases where multiple species coexist on only one externally supplied resource. Our stability criteria bear some resemblance to classic stability results for pairwise interactions, but also demonstrate how environmental context can shape coexistence patterns when resource limitation and exchange are modeled directly.
‘This disease is not meant for the hospital, it is Asram’: Implications of a traditionally-defined illness on healthcare seeking for children under-5 in rural Ashanti, Ghana
Authors: Acheampong Princess Ruhama , Mohammed Aliyu , Twumasi-Ankrah Sampson , Sylverken Augustina Angelina , Owusu Michael , Acquah-Gyan Emmanuel , Adjei Timothy Kwabena , Otupiri Easmon , Owusu-Dabo Ellis
Published: September 2022

Every child has the right to survive, grow and develop. However, in spite of the considerable global gains that have been made in child survival, Sub-Saharan Africa still has the highest child mortality rates and accounts for the greatest burden of mortality globally. The majority of these children die without ever reaching a health facility. The practice of appropriate healthcare-seeking behaviour has a great potential to reduce the occurrence of severe and life‐threatening childhood illnesses. Several factors, however, influence healthcare-seeking behaviour, including perceptions of the cause of illness and socio-cultural perspectives. This study seeks to understand local concepts of a traditionally-defined illness complex, Asram, and its influence on healthcare seeking behavior of mothers/caregivers. This qualitative study was conducted from October 2019 to February 2020. Four Focus Group Discussions were conducted with mothers/caregivers of children under-5 and 22 Key Informant Interviews with mothers/caregivers of children who had Asram, health workers at district, facility, and community levels, and Asram healers. Participants were selected from two rural communities, Akutuase and Wioso of the Asante Akim North district in the Ashanti region of Ghana. Data analysis was carried out iteratively throughout data collection, using a thematic analysis approach. The study shows that Asram is a childhood illness complex that is perceived to have been acquired spiritually and/or inherited. Nine types of Asram were described. This childhood illness was said to be treatable by Asram healers who had sub-specialties in treatment approaches that were determined by the Asram type reported. Mothers/caregivers trusted Asram healers and preferred to call on them first. This was found to be the main reason for delays in seeking healthcare for children under-5 who showed symptoms of Asram. Asram is a childhood illness complex that is believed to be better managed outside the health facility setting. This study complements existing knowledge and creates opportunities for further research and the introduction of more effective interventions in the effort to improve child survival in rural communities.