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1.
Space Sci Rev ; 216(5): 103, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32831412

RESUMO

The Electron Loss and Fields Investigation with a Spatio-Temporal Ambiguity-Resolving option (ELFIN-STAR, or heretoforth simply: ELFIN) mission comprises two identical 3-Unit (3U) CubeSats on a polar (∼93∘ inclination), nearly circular, low-Earth (∼450 km altitude) orbit. Launched on September 15, 2018, ELFIN is expected to have a >2.5 year lifetime. Its primary science objective is to resolve the mechanism of storm-time relativistic electron precipitation, for which electromagnetic ion cyclotron (EMIC) waves are a prime candidate. From its ionospheric vantage point, ELFIN uses its unique pitch-angle-resolving capability to determine whether measured relativistic electron pitch-angle and energy spectra within the loss cone bear the characteristic signatures of scattering by EMIC waves or whether such scattering may be due to other processes. Pairing identical ELFIN satellites with slowly-variable along-track separation allows disambiguation of spatial and temporal evolution of the precipitation over minutes-to-tens-of-minutes timescales, faster than the orbit period of a single low-altitude satellite (Torbit ∼ 90 min). Each satellite carries an energetic particle detector for electrons (EPDE) that measures 50 keV to 5 MeV electrons with Δ E/E < 40% and a fluxgate magnetometer (FGM) on a ∼72 cm boom that measures magnetic field waves (e.g., EMIC waves) in the range from DC to 5 Hz Nyquist (nominally) with <0.3 nT/sqrt(Hz) noise at 1 Hz. The spinning satellites (Tspin ∼ 3 s) are equipped with magnetorquers (air coils) that permit spin-up or -down and reorientation maneuvers. Using those, the spin axis is placed normal to the orbit plane (nominally), allowing full pitch-angle resolution twice per spin. An energetic particle detector for ions (EPDI) measures 250 keV - 5 MeV ions, addressing secondary science. Funded initially by CalSpace and the University Nanosat Program, ELFIN was selected for flight with joint support from NSF and NASA between 2014 and 2018 and launched by the ELaNa XVIII program on a Delta II rocket (with IceSatII as the primary). Mission operations are currently funded by NASA. Working under experienced UCLA mentors, with advice from The Aerospace Corporation and NASA personnel, more than 250 undergraduates have matured the ELFIN implementation strategy; developed the instruments, satellite, and ground systems and operate the two satellites. ELFIN's already high potential for cutting-edge science return is compounded by concurrent equatorial Heliophysics missions (THEMIS, Arase, Van Allen Probes, MMS) and ground stations. ELFIN's integrated data analysis approach, rapid dissemination strategies via the SPace Environment Data Analysis System (SPEDAS), and data coordination with the Heliophysics/Geospace System Observatory (H/GSO) optimize science yield, enabling the widest community benefits. Several storm-time events have already been captured and are presented herein to demonstrate ELFIN's data analysis methods and potential. These form the basis of on-going studies to resolve the primary mission science objective. Broad energy precipitation events, precipitation bands, and microbursts, clearly seen both at dawn and dusk, extend from tens of keV to >1 MeV. This broad energy range of precipitation indicates that multiple waves are providing scattering concurrently. Many observed events show significant backscattered fluxes, which in the past were hard to resolve by equatorial spacecraft or non-pitch-angle-resolving ionospheric missions. These observations suggest that the ionosphere plays a significant role in modifying magnetospheric electron fluxes and wave-particle interactions. Routine data captures starting in February 2020 and lasting for at least another year, approximately the remainder of the mission lifetime, are expected to provide a very rich dataset to address questions even beyond the primary mission science objective.

2.
Int J Oral Maxillofac Surg ; 49(4): 442-445, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31561844

RESUMO

At Queens Medical Centre, Nottingham, alveolar bone grafts (ABG) for patients with cleft lip and palate (CLP) were performed by two surgeons following the same surgical protocol, but with different postoperative iliac crest donor site analgesia: surgeon A used a donor site bolus of levobupivacaine, whilst surgeon B used a donor site epidural catheter (EC) infusing levobupivacaine. A healthcare evaluation was conducted in two phases to establish the effectiveness of analgesia for CLP patients undergoing ABGs. Data were collected prospectively in 2016 and 2018. Cleft patients postoperative to ABG were included. Outcome measures were pain scores at 2, 4, 6, 12, and 24 hours, time to mobilization, and time to food intake. Mean pain scores at the first evaluation were <1 out of 10 for all time points, except 24 hours (score 2.0 for bolus, 1.8 for EC). There was no statistically significant difference between the groups for any of the outcomes measured. As EC conferred no advantage, surgeon B changed to bolus administration and a second evaluation was performed. The mean pain score for the second evaluation was 1.7 and higher pain scores were more common with lower doses of levobupivacaine. The data suggest that bolus injection can produce safe, effective pain control provided an adequate dose is given.


Assuntos
Analgesia , Fissura Palatina , Transplante Ósseo , Humanos , Ílio , Dor , Dor Pós-Operatória
3.
Space Sci Rev ; 215(1): 9, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30880847

RESUMO

With the advent of the Heliophysics/Geospace System Observatory (H/GSO), a complement of multi-spacecraft missions and ground-based observatories to study the space environment, data retrieval, analysis, and visualization of space physics data can be daunting. The Space Physics Environment Data Analysis System (SPEDAS), a grass-roots software development platform (www.spedas.org), is now officially supported by NASA Heliophysics as part of its data environment infrastructure. It serves more than a dozen space missions and ground observatories and can integrate the full complement of past and upcoming space physics missions with minimal resources, following clear, simple, and well-proven guidelines. Free, modular and configurable to the needs of individual missions, it works in both command-line (ideal for experienced users) and Graphical User Interface (GUI) mode (reducing the learning curve for first-time users). Both options have "crib-sheets," user-command sequences in ASCII format that can facilitate record-and-repeat actions, especially for complex operations and plotting. Crib-sheets enhance scientific interactions, as users can move rapidly and accurately from exchanges of technical information on data processing to efficient discussions regarding data interpretation and science. SPEDAS can readily query and ingest all International Solar Terrestrial Physics (ISTP)-compatible products from the Space Physics Data Facility (SPDF), enabling access to a vast collection of historic and current mission data. The planned incorporation of Heliophysics Application Programmer's Interface (HAPI) standards will facilitate data ingestion from distributed datasets that adhere to these standards. Although SPEDAS is currently Interactive Data Language (IDL)-based (and interfaces to Java-based tools such as Autoplot), efforts are under-way to expand it further to work with python (first as an interface tool and potentially even receiving an under-the-hood replacement). We review the SPEDAS development history, goals, and current implementation. We explain its "modes of use" with examples geared for users and outline its technical implementation and requirements with software developers in mind. We also describe SPEDAS personnel and software management, interfaces with other organizations, resources and support structure available to the community, and future development plans. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s11214-018-0576-4) contains supplementary material, which is available to authorized users.

4.
Forensic Sci Int ; 122(2-3): 124-9, 2001 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11672965

RESUMO

We describe a minisequencing protocol for screening DNA samples for the presence of 12 mutations in the human melanocortin 1 receptor gene (MC1R), eight of which are associated with the red hair phenotype. A minisequencing profile which shows homozygosity for one of these mutations or the presence of two different mutations would strongly indicate that the sample donor is red haired. The absence of any red hair causing mutations would indicate that the sample donor does not have red hair. We report the frequencies of MC1R variants in the British red haired population.


Assuntos
Cor de Cabelo/genética , Reação em Cadeia da Polimerase/métodos , Receptores da Corticotropina/genética , Medicina Legal , Humanos , Fenótipo , Polimorfismo Genético , Receptores de Melanocortina
6.
J Dent Educ ; 63(6): 470-8, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10418566

RESUMO

In 1996, the American Dental Association's Commission on Dental Accreditation instituted a revised accreditation standard for dental hygiene educational programs entitled Standard 12-Outcomes Assessment. As a result of this standard, all dental hygiene programs were required to assess the attainment of goals through a formal outcomes assessment process. This study examined and analyzed the implementation process used by dental hygiene programs. Twenty-two dental hygiene program directors were interviewed to collect information regarding their experiences. The directors indicated that their programs routinely and effectively assess student outcomes and use the acquired information to make needed program improvements and to demonstrate accountability to groups having a vested interest in the program. Several factors, such as the policy itself, as well as gaining faculty and administrative support, were viewed as important to implementation. Time constraints were identified as a major barrier. Outcomes assessment data have also been used by dental hygiene programs as leverage for funding requests that resulted in significant program enhancement.


Assuntos
Higienistas Dentários/educação , Avaliação de Resultados em Cuidados de Saúde , Acreditação , Pessoal Administrativo , Higienistas Dentários/economia , Higienistas Dentários/organização & administração , Higienistas Dentários/normas , Docentes , Apoio Financeiro , Humanos , Objetivos Organizacionais , Política Organizacional , Estudantes , Fatores de Tempo
7.
J Endod ; 20(7): 355-6, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7996098

RESUMO

A 40-yr-old man was referred for the treatment of a large bony lesion of the mandible proximal to the root apices of the lower left first molar. Treatment had been done 7 to 8 yr previous to the examination, and the fill appeared to be adequate. Treatment was curettement of the lesion, apical curettage, and filling of the lesion with sterile freeze-dried bone. The patient was seen 6 months later and reported that he had been asymptomatic and was very pleased with the treatment. A postoperative radiograph was taken at that time and it showed that there had been an ingrowth of healthy bone into the bony lesion and that only a small radiolucency at the mesial root remained. In only 6 months, a very large lesion of the mandible had almost completely resolved after using freeze-dried bone to act as a matrix for the ingrowth of new bone tissue. At 7 months postoperatively, another radiograph was taken which showed continued healing.


Assuntos
Transplante Ósseo/métodos , Doenças Mandibulares/cirurgia , Cisto Radicular/cirurgia , Adulto , Regeneração Óssea , Liofilização , Humanos , Masculino , Dente Molar
8.
Trends Cell Biol ; 2(9): 263-7, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14731518

RESUMO

The discovery of apoptosis, a widespread and morphologically distinct form of physiological cell death, has had an extraordinary impact on cell biology. The importance of apoptosis stems from its active nature and its potential for controlling biological systems. The growing appreciation of the significance of this process has stimulated intense investigation into the molecular mechanisms involved and into its fundamental implications for developmental biology, immunology and oncology.

9.
Nucleic Acids Res ; 19(22): 6113-8, 1991 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-1956770

RESUMO

We have studied the effect of temperature on transcription initiation in vitro at two related promoters ga/Pcon and ga/P1, which have the same nucleotide sequence around the -10 region and transcription start site, but differ in upstream sequences. One of the promoters, ga/Pcon, carries the consensus -35 hexamer, 5'TTGACA 3', whilst ga/P1 contains a block of 'distortable' upstream sequences that allow promoter function in the absence of a -35 region consensus sequence. RNA polymerase can form complexes with both promoters at a range of temperatures. However, the thermal energy requirement for open complex formation differs: open complexes can form at ga/P1 at low temperatures, whereas ga/Pcon requires higher temperatures. The thermal energy requirement for transcription from preformed open complexes is the same for both promoters.


Assuntos
RNA Polimerases Dirigidas por DNA/metabolismo , Escherichia coli/enzimologia , Regiões Promotoras Genéticas , Termodinâmica , Transcrição Gênica , Sequência de Bases , Impressões Digitais de DNA , RNA Polimerases Dirigidas por DNA/genética , Galactose/genética , Dados de Sequência Molecular
10.
Biochim Biophys Acta ; 1064(2): 335-42, 1991 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-1827997

RESUMO

The sarcoplasmic reticulum (SR) of skeletal muscle contains a 53 kDa glycoprotein of unknown function, as well as the (Ca(2+)-Mg2+)-ATPase. It has been suggested that the glycoprotein couples the hydrolysis of ATP by the ATPase to the transport of calcium. It has been shown that if SR vesicles are solubilized in cholate in media containing low K+ concentrations followed by reconstitution, then vesicles are formed containing the glycoprotein and with ATP hydrolysis coupled to Ca2+ accumulation, as shown by a large stimulation of ATPase activity by addition of A23187. In contrast, if SR vesicles are solubilized in media containing a high concentration of K+, then the vesicles that are produced following reconstitution lack the glycoprotein and show low stimulation by A23187 (Leonards, K.S. and Kutchai, H. (1985) Biochemistry 24, 4876-4884). We show that the effect of K+ on reconstitution does not follow from any changes in the amount of glycoprotein but rather from an effect of K+ on the detergent properties of cholate. In low K+ media, the cmc of cholate is high, cholate is a relatively poor detergent and incomplete solubilization results in 'reconstitution' of vesicles with the correct orientation of ATPase molecules. In high K+ media, the cmc of cholate is reduced and more complete solubilization of the SR leads to a true reconstitution with the formation of vesicles with a random orientation of ATPase molecules. The experiments provide no evidence for an effect of the glycoprotein on the (Ca(2+)-Mg2+)-ATPase.


Assuntos
Trifosfato de Adenosina/metabolismo , ATPase de Ca(2+) e Mg(2+)/metabolismo , ATPases Transportadoras de Cálcio/metabolismo , Cálcio/metabolismo , Glicoproteínas/fisiologia , Cloreto de Potássio/farmacologia , Retículo Sarcoplasmático/enzimologia , Animais , Transporte Biológico , Calcimicina/farmacologia , Hidrólise , Bicamadas Lipídicas , Peso Molecular , Retículo Sarcoplasmático/efeitos dos fármacos
11.
Biochim Biophys Acta ; 1064(1): 139-47, 1991 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-1827350

RESUMO

m-Maleimidobenzoyl-N-hydroxysuccinimide ester (MBS) was used to cross-link the protein components of rabbit skeletal muscle sarcoplasmic reticulum. Analysis of cross-linked material by SDS-polyacrylamide gel electrophoresis showed that both the (Ca(2+)-Mg2+)-ATPase and the 53 kDa glycoprotein could be cross-linked, since the amount of protein at the locations on the gel corresponding to uncross-linked material was reduced in the presence of 1.0 mM MBS. Cross-linked products of 130 kDa, 200-260 kDa and approx. 300 kDa were identified. Probing the cross-linked products with monoclonal antibodies against ATPase, 53 kDa glycoprotein and calsequestrin revealed no cross-linked products containing the ATPase and either calsequestrin or the 53 kDa glycoprotein over the range of molecular weights examined here. Possible interactions between the ATPase and calsequestrin or the 53 kDa glycoprotein were also investigated by studying the ATPase activity for the purified ATPase and for the ATPase in sarcoplasmic reticulum vesicles made permeable to Ca2+ with A23187. Effects of Ca2+ and ATP on the two systems were indistinguishable, providing no evidence for a major modulatory role of calsequestrin or the 53 kDa glycoprotein on the ATPase.


Assuntos
Cálcio/metabolismo , Reagentes de Ligações Cruzadas , Glicoproteínas de Membrana/metabolismo , Retículo Sarcoplasmático/metabolismo , Trifosfato de Adenosina/farmacologia , Animais , Anticorpos Monoclonais , Transporte Biológico , Western Blotting , ATPase de Ca(2+) e Mg(2+)/metabolismo , Calcimicina/farmacologia , Cálcio/farmacologia , ATPases Transportadoras de Cálcio/metabolismo , Calsequestrina/metabolismo , Eletroforese em Gel de Poliacrilamida/métodos , Cinética , Glicoproteínas de Membrana/imunologia , Proteínas/análise , Coelhos , Retículo Sarcoplasmático/efeitos dos fármacos , Succinimidas
13.
Biochemistry ; 30(2): 342-51, 1991 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-1824818

RESUMO

The ATPase activity for the (Ca2(+)-Mg2+)-ATPase purified from rabbit skeletal muscle sarcoplasmic reticulum is lower when reconstituted into bilayers of dimyristoleoylphosphatidylcholine [(C14:1)PC] than when it is reconstituted into dioleoylphosphatidylcholine [(C18:1)PC]. The rate of formation of phosphoenzyme on addition of ATP is slower for (C14:1)PC-ATPase than for the native ATPase or (C18:1)PC-ATPase. The reduction in rate of phosphoenzyme formation is attributed to a reduction in the rate of a conformational change on the ATPase following binding of ATP but before phosphorylation. The level of phosphoenzyme formed from Pi is also less for (C14:1)PC-ATPase than for (C18:1)PC-ATPase. At steady state at pH 6.0 in the presence of ATP Ca2+ is released from (C18:1)PC-ATPase into the medium, but not from (C14:1)PC-ATPase. These effects of (C14:1)PC on the ATPase are reversed by addition of androstenol to a 1:1 molar ratio with (C14:1)PC. The results are interpreted in terms of a kinetic model for the ATPase.


Assuntos
ATPase de Ca(2+) e Mg(2+)/metabolismo , ATPases Transportadoras de Cálcio/metabolismo , Fosfolipídeos/fisiologia , Trifosfato de Adenosina/metabolismo , Animais , Cálcio/fisiologia , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Cinética , Bicamadas Lipídicas , Fosfatidilcolinas , Fosforilação , Coelhos , Retículo Sarcoplasmático/enzimologia , Relação Estrutura-Atividade
14.
Biochemistry ; 29(36): 8307-12, 1990 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-2147565

RESUMO

The (Ca2(+)-Mg2(+)-ATPase purified from skeletal muscle sarcoplasmic reticulum binds two Ca2+ ions per ATPase molecule. On reconstitution into bilayers of dioleoylphosphatidylcholine [C18:1)PC) or dinervonylphosphatidylcholine [C24:1)PC) the stoichiometry of binding remains unchanged, but when the ATPase is reconstituted into bilayers of dimyristoleoylphosphatidylcholine [C14:1)PC) the stoichiometry changes to one Ca2+ ion per ATPase molecule. Nevertheless, the level of phosphorylation is the same for the ATPase reconstituted with (C18:1)PC or (C14:1)PC. The effect of (C14:1)PC on the stoichiometry of Ca2+ binding is prevented by androstenol at a 1:1 molar ratio with the phospholipid.


Assuntos
ATPase de Ca(2+) e Mg(2+)/metabolismo , ATPases Transportadoras de Cálcio/metabolismo , Cálcio/metabolismo , Lipídeos de Membrana/farmacologia , Fosfolipídeos/farmacologia , Androstenóis/farmacologia , Animais , Dimiristoilfosfatidilcolina/farmacologia , Bicamadas Lipídicas , Fosfatidilcolinas/farmacologia , Fosforilação , Ligação Proteica/efeitos dos fármacos , Conformação Proteica/efeitos dos fármacos , Coelhos
15.
Gene ; 90(1): 1-7, 1990 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-2165969

RESUMO

A novel technique for the creation of rare restriction sites was described by Koob et al. [Science 241 (1988) 1084-1086]. This technique, Achilles' heel cleavage (AC), relies on the use of a bound repressor molecule to protect only one of many identical restriction sites from a modification methyltransferase that inactivates all other restriction sites. The technique was applied to a small plasmid and shown to work efficiently with two repressor/operator systems: lac repressor/lacO operator and lambda repressor/lambda oL1 operator. Here, we have extended these results to a lac operator carried by a much larger vector, namely a 44-kb phage lambda construct. In addition, we have evaluated the effect of altering the stability of the lac repressor/lac operator complex by varying both the operator and the repressor. We have also evaluated several more restriction/modification systems (MboI, Dam, MspI and AluI) in addition to HhaI and HaeII used earlier. Finally, we extended the AC technique to a third system, that of the phage 434 repressor and a synthetic 434 operator. From our results we conclude that the AC method should be applicable to the mapping of large genomes and to measuring the strength of operator-repressor interactions. AC could also be applied to identifying and evaluating many different DNA-binding proteins and their sites of action.


Assuntos
Bacteriófago lambda/genética , Enzimas de Restrição do DNA/metabolismo , Proteínas Repressoras/metabolismo , Mapeamento por Restrição , Fatores de Transcrição/metabolismo , Sequência de Bases , Óperon Lac , Dados de Sequência Molecular , Regiões Operadoras Genéticas
16.
Arch Androl ; 24(2): 215-9, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2327832

RESUMO

The exact role of varicocele in human male infertility remains controversial. Fifty-five male partners of infertile couples randomly selected and 17 fertile semen donors were evaluated for semen quality, scrotal temperature, and presence of varicocele using clinical palpation and Doppler ultrasound. The incidence of varicocele was 42% in male partners of infertile couples and 41% in fertile semen donors. Left scrotal temperature was significantly (p less than .001) higher in infertile males with varicocele as compared to all groups. No significant differences were observed in the percentage of morphologically normal sperm in semen of males with and without varicocele. However, the incidence of tapered, elongated, and immature sperm was significantly higher in the infertile patient population with a varicocele. Measurement of scrotal temperature and assessment of sperm morphology may be used as predictors of the presence and deleterious effect of varicocele.


Assuntos
Infertilidade Masculina/patologia , Escroto/fisiologia , Espermatozoides/patologia , Varicocele/patologia , Temperatura Corporal , Humanos , Infertilidade Masculina/complicações , Infertilidade Masculina/fisiopatologia , Masculino , Varicocele/complicações , Varicocele/fisiopatologia
18.
Arch Androl ; 22(3): 191-5, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2474268

RESUMO

Two semen specimens from 34 fertile donors and 82 male partners of infertile couples were evaluated for semen quality. Sperm morphology was evaluated with unstained specimens and following Papanicolaou staining. A significant difference (p less than 0.001) was found in the percentage of morphologically normal spermatozoa in stained and unstained semen smears. Fertile semen donors had a significantly (p less than 0.001) higher percentage of normal sperm than men of unproven fertility. When compared to the fertile donors, 78% of the infertile men had increased teratospermia. Papanicolaou staining appears to enhance sperm morphology and allow improved discrimination of sperm head abnormalities.


Assuntos
Fertilidade , Espermatozoides/citologia , Humanos , Infertilidade , Masculino , Sêmen/análise , Espermatozoides/anormalidades , Coloração e Rotulagem , Relação Estrutura-Atividade
20.
Science ; 241(4869): 1084-6, 1988 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-2842862

RESUMO

Mapping and manipulation of very large genomes, including the human genome, would be facilitated by the availability of a DNA cleavage method with very high site specificity. Therefore, a general method was devised that extends the effective recognition sequences well beyond the present 8-base pair limit by combining the specificity of the restriction endonuclease with that of another sequence-specific protein that binds tightly to DNA. It was shown that the tightly binding lac or lambda repressor protects a restriction site within the operator from specific modification methylases, M.Hha I or M.Hph I, while all other similar sites are methylated and thus rendered uncleavable. A plasmid containing a symmetric lac operator was specifically cleaved by Hha I, only at the site within the operator, after M.Hha I methylation in the presence of the lac repressor, whereas the remaining 31 Hha I sites on this plasmid were methylated and thus not cleaved. Analogous results were obtained with the Hae II site within the lac operator, which was similarly protected by the lac repressor, and with the Hph I site within the phage lambda oL operator, which was protected by lambda repressor from M.Hph I methylation.


Assuntos
Enzimas de Restrição do DNA/metabolismo , DNA/metabolismo , Regiões Operadoras Genéticas , Bacteriófago lambda/análise , Bacteriófago lambda/genética , Temperatura Alta , Óperon Lac , Metilação , Plasmídeos , Proteínas Repressoras/metabolismo , Especificidade por Substrato
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