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Erikssen, Gunnar, Jamil Aboulhosn, Jeannette Lin, Knut Liestøl, Mette E. Estensen, Ola Gjesdal, Helge Skulstad, Gaute Døhlen, and Harald Lauritz Lindberg. "Survival in patients with univentricular hearts: the impact of right versus left ventricular morphology." Open Heart 5, no. 2 (October 2018): e000902. http://dx.doi.org/10.1136/openhrt-2018-000902.
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ObjectivePatients with univentricular hearts (UVH) have high mortality despite modern treatment, and better methods to identify patients at highest risk are needed. We wanted to improve risk stratification in patients with UVH by focusing on the prognostic significance of single right versus single left ventricular morphology (SRV vs SLV).MethodsAll 395 patients with UVH operated at our centre were prospectively included from 1972 to 2016 (195 SRV, 166 SLV, 34 mixed or indeterminate ventricular morphology). Diagnoses, UVH morphology, types of all operations and time and causes of death or heart transplantation (HTX) were recorded. The primary endpoint was death or HTX.ResultsAmong the 111 non-Fontan patients, 88 died (SRV 62 vs SLV 20; p<0.0001), 32 due to heart failure (SRV 23 vs SLV 5; p=0.0012). Twenty-five years of cumulative SRV versus SLV survival among the 284 Fontan patients (41 deaths/HTX) was 66.9% vs 87.9% (p=0.0027), partly explained by more deaths/HTX due to heart failure among patients with SRV (p=0.0006). Survival in patients with SRV with and without hypoplastic left heart syndrome (HLHS) was similar. SRV versus SLV was a strong predictor of death/HTX in multivariable proportional hazards analyses (RR 3.3, 95% CI 1.6 to 6.6).ConclusionSRV versus SLV is a strong short-term and long-term predictor of survival among patients with UVH, mainly explained by higher rates of death/HTX due to heart failure in the SRV group. Our findings apply to patients with SRV both with and without HLHS.
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van der Kuyl, Antoinette C. "Contemporary Distribution, Estimated Age, and Prehistoric Migrations of Old World Monkey Retroviruses." Epidemiologia 2, no. 1 (February 3, 2021): 46–67. http://dx.doi.org/10.3390/epidemiologia2010005.
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Old World monkeys (OWM), simians inhabiting Africa and Asia, are currently affected by at least four infectious retroviruses, namely, simian foamy virus (SFV), simian immunodeficiency virus (SIV), simian T-lymphotropic virus (STLV), and simian type D retrovirus (SRV). OWM also show chromosomal evidence of having been infected in the past with four more retroviral species, baboon endogenous virus (BaEV), Papio cynocephalus endogenous virus (PcEV), simian endogenous retrovirus (SERV), and Rhesus endogenous retrovirus-K (RhERV-K/SERV-K1). For some of the viruses, transmission to other primates still occurs, resulting, for instance, in the HIV pandemic. Retroviruses are intimately connected with their host as they are normally spread by close contact. In this review, an attempt to reconstruct the distribution and history of OWM retroviruses will be made. A literature overview of the species infected by any of the eight retroviruses as well as an age estimation of the pathogens will be given. In addition, primate genomes from databases have been re-analyzed for the presence of endogenous retrovirus integrations. Results suggest that some of the oldest retroviruses, SERV and PcEV, have travelled with their hosts to Asia during the Miocene, when a higher global temperature allowed simian expansions. In contrast, younger viruses, such as SIV and SRV, probably due to the lack of a primate continuum between the continents in later times, have been restricted to Africa and Asia, respectively.
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Switzer, William M., Vinod Bhullar, Vedapuri Shanmugam, Mian-er Cong, Bharat Parekh, Nicholas W. Lerche, JoAnn L. Yee, et al. "Frequent Simian Foamy Virus Infection in Persons Occupationally Exposed to Nonhuman Primates." Journal of Virology 78, no. 6 (March 15, 2004): 2780–89. http://dx.doi.org/10.1128/jvi.78.6.2780-2789.2004.
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ABSTRACT The recognition that AIDS originated as a zoonosis heightens public health concerns associated with human infection by simian retroviruses endemic in nonhuman primates (NHPs). These retroviruses include simian immunodeficiency virus (SIV), simian T-cell lymphotropic virus (STLV), simian type D retrovirus (SRV), and simian foamy virus (SFV). Although occasional infection with SIV, SRV, or SFV in persons occupationally exposed to NHPs has been reported, the characteristics and significance of these zoonotic infections are not fully defined. Surveillance for simian retroviruses at three research centers and two zoos identified no SIV, SRV, or STLV infection in 187 participants. However, 10 of 187 persons (5.3%) tested positive for SFV antibodies by Western blot (WB) analysis. Eight of the 10 were males, and 3 of the 10 worked at zoos. SFV integrase gene (int) and gag sequences were PCR amplified from the peripheral blood lymphocytes available from 9 of the 10 persons. Phylogenetic analysis showed SFV infection originating from chimpanzees (n = 8) and baboons (n = 1). SFV seropositivity for periods of 8 to 26 years (median, 22 years) was documented for six workers for whom archived serum samples were available, demonstrating long-standing SFV infection. All 10 persons reported general good health, and secondary transmission of SFV was not observed in three wives available for WB and PCR testing. Additional phylogenetic analysis of int and gag sequences provided the first direct evidence identifying the source chimpanzees of the SFV infection in two workers. This study documents more frequent infection with SFV than with other simian retroviruses in persons working with NHPs and provides important information on the natural history and species origin of these infections. Our data highlight the importance of studies to better define the public health implications of zoonotic SFV infections.
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Serra, Ilka Márcia R. de S., and Gilson S. da Silva. "Caracterização biológica e fisiológica de isolados de Sclerotium rolfsii obtidos de pimentão no Estado do Maranhão." Fitopatologia Brasileira 30, no. 1 (February 2005): 61–66. http://dx.doi.org/10.1590/s0100-41582005000100010.
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A murcha de esclerócio do pimentão (Capsicum annum), causada por Sclerotium rolfsii é uma das mais importantes doenças dessa solanácea, nas regiões tropicais. Um dos requisitos básicos para obtenção de sucesso no controle dessa doença é o conhecimento do patógeno, especialmente de fatores relacionados à fisiologia e biologia. O presente trabalho teve como objetivo caracterizar cinco isolados de S. rolfsii, obtidos de pimentão, quanto ao crescimento micelial, produção de escleródios em diferentes regimes de luminosidade e em seis substratos naturais e a compatibilidade vegetativa entre os isolados. O efeito do substrato variou com o isolado na produção de escleródios. Os isolados SR3 e SR5 apresentaram maior produção de escleródios nos substratos aveia-ágar (AA) e fubá-ágar (FA), SR1 em casca de arroz (CA), SR2 em AA e SR4 em FA. O substrato CA favoreceu a formação de escleródios na maioria dos isolados. Quanto à taxa de crescimento micelial os isolados apresentaram pouca variação, sendo SR1, SR2 e SR3 os que apresentaram maior crescimento. Os cincos isolados exibiram comportamento diferente quando submetidos a três regimes de luz (luz contínua, alternância luminosa e escuro contínuo), tendo o primeiro favorecido maior produção de escleródios em relação aos outros. O teste de compatibilidade vegetativa mostrou diversidade genética entre os cincos isolados, possibilitando a classificação em três grupos. Os isolados SR3 e SR5 foram incompatíveis com os demais e entre si. Houve compatibilidade vegetativa entre os isolados SR1, SR2 e SR4. De acordo com os aspectos culturais e fisiológicos estudados, os isolados de S. rolfsii SR3 e SR5 podem ser considerados "strains" diferentes, enquanto SR1, SR2 e SR4 podem ser considerados da mesma "strain".
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Yee, JoAnn L., Richard F. Grant, Koen K. A. Van Rompay, Jeffrey A. Roberts, LaRene Kuller, Jesse L. Cunningham, Joe H. Simmons, and James F. Papin. "In vitro and In vivo Susceptibility of Baboons (Papio sp.) to Infection with and Apparent Antibody Reactivity to Simian Betaretrovirus (SRV)." Comparative Medicine 70, no. 1 (February 1, 2020): 75–82. http://dx.doi.org/10.30802/aalas-cm-19-000014.
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Despite the lack of confirmed reports of an exogenous Simian betaretrovirus (SRV) isolated from baboons (Papio sp.), reports of simian endogenous gammaretrovirus (SERV) in baboons with complete genomes suggest that such viruses may be potentially infectious. In addition, serologic tests have repeatedly demonstrated antibody reactivity to SRV in baboons from multiple colonies. These findings complicate the management and use of such animals for research. To provide further insight into this situation, we performed in vitro and in vivo studies to determine if baboons are or can be infected with SRV. In our initial experiment, we were not able to isolate SRV from 6 seropositive or sero-indeterminate baboons by coculturing their peripheral blood mononuclear cells (PBMC) with macaque PBMC or permissive cell lines. In a subsequent experiment, we found that baboon PBMC infected in vitro with high dose SRV were permissive to virus replication. To test in vivo infectibil- ity, groups of naive baboons were infused intravenously with either (i) the same SRV tissue culture virus stocks used for the in vitro studies, (ii) SRV antibody positive and PCR positive macaque blood, (iii) SRV antibody positive or indeterminate, but PCR negative baboon blood, or (iv) SRV antibody and PCR negative baboon blood. Sustained SRV infection, as defined by reproducible PCR detection and/or antibody seroconversion, was confirmed in 2 of 3 baboons receiving tissue culture virus but not in any recipients of transfused blood from seropositive macaques or baboons. In conclusion, the data indicate that even though baboon cells can be infected experimentally with high doses of tissue culture grown SRV, baboons that are repeatedly SRV antibody positive and PCR negative are unlikely to be infected with exogenous SRV and thus are unlikely to transmit a virus that would threaten the SPF status of captive baboon colonies.
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Chen, Li-Jun, Zhi-Rong Tong, Qian Wang, Yu-Qi Zhang, and Jin-Long Liu. "Feasibility of Computational Fluid Dynamics for Evaluating the Intraventricular Hemodynamics in Single Right Ventricle Based on Echocardiographic Images." BioMed Research International 2018 (2018): 1–11. http://dx.doi.org/10.1155/2018/1042038.
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This study introduced a combined computational fluid dynamics (CFD) and echocardiography methodology to simulate blood flow in the single right ventricle (SRV) and normal ventricles to study the intraventricular flow. Derived from echocardiographic image loops, CFD-based three-dimensional (3D) flow models of normal subject’s left ventricle (LV) and right ventricle (RV) and SRV with and without heart failure at three characteristic diastolic statuses were reconstructed. The CFD derived morphological and functional measurements in normal ventricles and the SRV were validated with echocardiography. The vortex in the normal ventricles and the SRV were studied. The morphological and functional measurements derived from CFD modeling and echocardiography were comparable, and both methods demonstrated the larger volume and higher spherical index in the SRV, in particular the SRV with heart failure. All the vortices in the SRV were smaller than those in the normal control subject’s LV and RV, notably with heart failure. Unlike normal LV and RV, no vortex ring was observed in the SRV. Echocardiography-based CFD demonstrated the feasibility of quantifying ventricular morphology and function; in addition, CFD can detect the abnormal flow pattern (smaller or obliterated vortices) in the SRV when compared with normal ventricles.
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Takano, Jun-Ichiro, Arlene Leon, Miyoko Kato, Yuko Abe, and Koji Fujimoto. "Isolation and DNA characterization of a simian retrovirus 5 from a Japanese monkey (Macaca fuscata)." Journal of General Virology 94, no. 5 (May 1, 2013): 955–59. http://dx.doi.org/10.1099/vir.0.047621-0.
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An SRV-like virus was isolated from a colony-born Japanese monkey. To identify this SRV-like virus, we designed universal primers at regions that were conserved among the reported SRV sequences in the 5′-LTR and the short ORF and we obtained plasmid clones containing the complete gag, prt, pol and env genes. The full-length sequences of the isolate were determined from the plasmids and by direct sequencing. Sequence comparisons and phylogenetic analyses indicated that this SRV-like virus had a sequence identical to the reported 626 bp of SRV-5. In this study, we isolated SRV5/JPN/2005/V1 from a Japanese monkey and characterized the full-length SRV-5 sequence.
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Zhu, Jingting, Lingyan Yang, Qibo Zhang, Jia Meng, Zhi-Liang Lu, and Rong Rong. "Autophagy Induced by Simian Retrovirus Infection Controls Viral Replication and Apoptosis of Jurkat T Lymphocytes." Viruses 12, no. 4 (March 31, 2020): 381. http://dx.doi.org/10.3390/v12040381.
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Autophagy and apoptosis are two important evolutionarily conserved host defense mechanisms against viral invasion and pathogenesis. However, the association between the two pathways during the viral infection of T lymphocytes remains to be elucidated. Simian type D retrovirus (SRV) is an etiological agent of fatal simian acquired immunodeficiency syndrome (SAIDS), which can display disease features that are similar to acquired immunodeficiency syndrome in humans. In this study, we demonstrate that infection with SRV-8, a newly isolated subtype of SRV, triggered both autophagic and apoptotic pathways in Jurkat T lymphocytes. Following infection with SRV-8, the autophagic proteins LC3 and p62/SQSTM1 interacted with procaspase-8, which might be responsible for the activation of the caspase-8/-3 cascade and apoptosis in SRV-8-infected Jurkat cells. Our findings indicate that autophagic responses to SRV infection of T lymphocytes promote the apoptosis of T lymphocytes, which, in turn, might be a potential pathogenetic mechanism for the loss of T lymphocytes during SRV infection.
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Yoshikawa, Rokusuke, Munehiro Okamoto, Shoichi Sakaguchi, So Nakagawa, Tomoyuki Miura, Hirohisa Hirai, and Takayuki Miyazawa. "Simian Retrovirus 4 Induces Lethal Acute Thrombocytopenia in Japanese Macaques." Journal of Virology 89, no. 7 (January 21, 2015): 3965–75. http://dx.doi.org/10.1128/jvi.03611-14.
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ABSTRACTIn 2001-2002, six of seven Japanese macaques (Macaca fuscata) died after developing hemorrhagic syndrome at the Kyoto University Primate Research Institute (KUPRI). While the cause of death was unknown at the time, we detected simian retrovirus 4 (SRV-4) in samples obtained from a similar outbreak in 2008-2011, during which 42 of 43 Japanese macaques died after exhibiting hemorrhagic syndrome. In this study, we isolated SRV-4 strain PRI-172 from a Japanese macaque showing severe thrombocytopenia. When inoculated into four Japanese macaques, the isolate induced severe thrombocytopenia in all within 37 days. We then constructed an infectious molecular clone of strain PRI-172, termed pSR415, and inoculated the clone-derived virus into two Japanese macaques. These animals also developed severe thrombocytopenia in just 31 days after inoculation, and the virus was reisolated from blood, bone marrow, and stool. At necropsy, we observed bleeding from the gingivae and subcutaneous bleeding in all animals. SRV-4 infected a variety of tissues, especially in digestive organs, including colon and stomach, as determined by real-time reverse transcription-PCR (RT-PCR) and immunohistochemical staining. Furthermore, we identified the SRV-4 receptor as ASCT2, a neutral amino acid transporter. ASCT2 mRNA was expressed in a variety of tissues, and the distribution of SRV-4 proviruses in infected Japanese macaques correlated well with the expression levels of ASCT2 mRNA. From these results, we conclude that the causative agent of hemorrhagic syndrome in KUPRI Japanese macaques was SRV-4, and its receptor is ASCT2.IMPORTANCEDuring two separate outbreaks at the KUPRI, in 2001-2002 and 2008-2011, 96% of Japanese macaques (JM) that developed an unknown hemorrhagic syndrome died. Here, we isolated SRV-4 from a JM developing thrombocytopenia. The SRV-4 isolate and a molecularly cloned SRV-4 induced severe thrombocytopenia in virus-inoculated JMs within 37 days. At necropsy, we observed bleeding from gingivae and subcutaneous bleeding in all affected JMs and reisolated SRV-4 from blood, bone marrow, and stool. The distribution of SRV-4 proviruses in tissues correlated with the mRNA expression levels of ASCT2, which we identified as the SRV-4 receptor. From these results, we conclude that SRV-4 was the causative agent of hemorrhagic syndrome in JMs in KUPRI.
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Wilkinson, Roseanne C., Claire K. Murrell, Rebecca Guy, Gail Davis, Joanna M. Hall, David C. North, Nicola J. Rose, and Neil Almond. "Persistence and Dissemination of Simian Retrovirus Type 2 DNA in Relation to Viremia, Seroresponse, and Experimental Transmissibility in Macaca fascicularis." Journal of Virology 77, no. 20 (October 15, 2003): 10751–59. http://dx.doi.org/10.1128/jvi.77.20.10751-10759.2003.
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ABSTRACT Endemic simian retrovirus (SRV) infection can cause fatal simian AIDS in Macaca fascicularis, but many individuals survive with few clinical signs. To further clarify the parameters of SRV pathogenesis, we investigated the persistence of viral DNA forms in relation to active viremia, antibody response, and transmissibility of infection. In M. fascicularis from endemically SRV-2-infected colonies, viral DNA was present in both linear and unintegrated long terminal repeat circular forms in peripheral blood mononuclear cells of all viremic and many nonviremic animals. Long-term followup of three individuals with distinct infection patterns demonstrated persistence of linear and circular forms of viral DNA in peripheral blood mononuclear cells and tissues, irrespective of viremia or antibody status, but reactivation of latent infections was not observed. The role of viral DNA in transmission and early pathogenesis of SRV-2 was investigated by inoculation of SRV-2 DNA-positive blood into groups of naïve M. fascicularis from either a viremic or nonviremic donor and subsequent analysis of the virological and serological status of the recipients. Transmission of SRV and development of anti-SRV antibodies were only observed in recipients of blood from the viremic donor; transfer of SRV provirus and unintegrated circular DNA in blood from the nonviremic donor did not lead to infection of the recipients. These results indicate that a proportion of M. fascicularis are able to effectively control the replication and infectivity of SRV despite long-term persistence of viral DNA forms in infected lymphocytes.
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Yu, Pujia, Shiwei Liu, Zhi Ding, Aichun Zhang, and Xuguang Tang. "Changes in Storage and the Stratification Ratio of Soil Organic Carbon under Different Vegetation Types in Northeastern China." Agronomy 10, no. 2 (February 18, 2020): 290. http://dx.doi.org/10.3390/agronomy10020290.
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The depth distribution of soil organic carbon (SOC) in a soil profile is important to examine the effects of different treatments on SOC sequestration. This study was conducted to determine the effects of different vegetation types on the concentration, storage, and stratification ratio (SR) of SOC in northeastern China. Five vegetation types, Leymus chinensis (LEY), Puccinellia tenuiflora (PUC), Echinochloa phyllopogon (ECH), saline seepweed (SUA), and Chloris virgata Swartz (CHL), were selected as treatments. Soil bulk density and SOC concentration were measured at 0 to 50 cm depth, and SOC storage and four SRs (SR1 [0–10:10–20 cm], SR2 [0–10:20–30 cm], SR3 [0–10:30–40 cm], and SR4 [0–10:40–50 cm]) were calculated under the five vegetation types. Results showed a pronounced reduction in SOC concentration with increasing soil depth. Vegetation types had significant effects on SOC concentration and storage. Under PUC, ECH, SUA, and CHL treatments, SOC concentrations (2.150, 1.068, 4.110, and 2.542 g kg−1, respectively) and storages (15.075, 7.273, 30.024, and 18.078 Mg ha−1, respectively) at 0–50 cm depth were lower than those under the LEY treatment. SR1 values were all < 2, while SR2, SR3, and SR4 values were all > 2 except for SR2 under ECH and SUA treatments. Vegetation types had significant effects on SR3 (p < 0.001) and SR4 (p = 0.040), while no significant differences were found for SR1 and SR2 due to the narrow range, with values of 0.248 and 0.553 for SR1 and SR2, respectively, among the vegetation types. These results indicated that the degraded soils have great potential to sequester organic carbon in northeastern China, and SR3 could be used as an effective index to show the changes in SOC concentration and soil quality in northeastern China.
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Sobolev, Alexander V., Galina V. Ryabykina, and Elena Sh Kozhemyakina. "Specificity of the effect of double fractures of the rhythmogram on the daily variability of the sinus rhythm in patients with pulmonary and arterial hypertension." Systemic Hypertension 18, no. 1 (March 15, 2021): 43–49. http://dx.doi.org/10.26442/2075082x.2021.1.200722.
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Introduction. In contrast to coronary heart disease (CHD), heart failure and a number of other diseases, in arterial and pulmonary hypertension, the deterioration of the functional state of the patient is often not accompanied by a decrease in the parameters of his sinus rhythm variability (SRV) for long periods of time. Moreover, an increase in age and an increase in blood pressure in patients with hypertension may lead not to a decrease, but to an increase in the parameters of daily SRV. It is noted that with hypertension on the sinus rhythm, the number of so-called double fractures of the rhythmogram (DFR) sequences of RR intervals short-long-short-long becomes greater, which can greatly affect the daily SRV.
Aim. To study the specifics of the effect of DFR on daily SRV in arterial and pulmonary hypertension.
Materials and methods. 300 Holter ECG records were analyzed, including 67 records of healthy persons, 20 records of CHD patients with CAG-confirmed vascular damage, 126 records of patients with arterial hypertension and 87 records of patients with idiopathic pulmonary hypertension. In the analysis of daily SRV, a modification of the SRV analysis method developed at the National Medical Research Center of Cardiology, taking into account the presence of DFR, was used.
Results. It is shown that DFR reflects the processes of regulation of the sinus rhythm, which are affected differently by CHD and hypertension. In CHD, the frequency of DFR and its effect on the daily SRV significantly decreases (compared to the norm). With hypertension, the frequency of the appearance of DFR increases; there is a clear trend towards a decrease in SRV in comparison with the norm in the areas without DFR; in areas with DFR, this trend is less pronounced or absent, and at ages over 50 years, SRV increases.
Conclusion. When studying the daily SRV of patients with arterial and idiopathic pulmonary hypertension, it is necessary to take into account the effect of DFR on the increase in SRV.
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Lerche, Nicholas W., and Kent G. Osborn. "Simian Retrovirus Infections: Potential Confounding Variables in Primate Toxicology Studies." Toxicologic Pathology 31, no. 1_suppl (January 2003): 103–10. http://dx.doi.org/10.1080/01926230390174977.
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Various species of nonhuman primates are natural hosts for 6 exogenous retroviruses, including gibbon-ape leukemia virus (GaLV), simian sarcoma virus, simian T-lymphotropic virus (STLV), simian immunodeficiency virus (SIV), simian type D retrovirus (SRV), and simian foamy virus (SFV). These viruses establish persistent infections with a broad spectrum of pathogenic potential, ranging from highly pathogenic to nonpathogenic, depending on various host, virus, and environmental factors. Latent or subclinical infections are common, and various procedures associated with experimental protocols may lead to virus reactivation and disease. Adverse effects on toxicologic research by undetected retroviral infections can occur in several ways, including loss of experimental subjects (and statistical power) due to increased morbidity and mortality. In addition, results may be confounded by virus-induced clinical abnormalities, histologic lesions, alteration of physiologic parameters and responses, and interference with in vitro assays and/or destruction of primary cell cultures. Key clinical and epidemiological features of several important retroviruses are reviewed, with emphasis on viruses infecting species of macaques most commonly used as research subjects in primate toxicology studies. Examples of actual and potential confounding of toxicologic studies by retroviruses are discussed, including altered cytokine profiles in healthy STLV carriers, and clinical and pathological abnormalities induced by SRV infection. Adequate prestudy viral screening is critical to exclude retrovirus-infected primates from toxicologic research protocols and prevent potential confounding of research results.
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Lerche, Nicholas W., William M. Switzer, JoAnn L. Yee, Vedapuri Shanmugam, Ann N. Rosenthal, Louisa E. Chapman, Thomas M. Folks, and Walid Heneine. "Evidence of Infection with Simian Type D Retrovirus in Persons Occupationally Exposed to Nonhuman Primates." Journal of Virology 75, no. 4 (February 15, 2001): 1783–89. http://dx.doi.org/10.1128/jvi.75.4.1783-1789.2001.
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ABSTRACT Simian type D retrovirus (SRV) is enzootic in many populations of Asian monkeys of the genus Macaca and is associated with immunodeficiency diseases. However, the zoonotic potential of this agent has not been well defined. Screening for antibodies to SRV was performed as part of an ongoing study looking for evidence of infection with simian retroviruses among persons occupationally exposed to nonhuman primates (NHPs). Of 231 persons tested, 2 (0.9%) were found to be strongly seropositive, showing reactivity against multiple SRV antigens representing gag, pol, andenv gene products by Western immunoblotting. Persistent long-standing seropositivity, as well as neutralizing antibody specific to SRV type 2, was documented in one individual (subject 1), while waning antibody with eventual seroreversion was observed in a second (subject 2). Repeated attempts to detect SRV by isolation in tissue culture and by using sensitive PCR assays for amplification of two SRV gene regions (gag and pol) were negative. Both individuals remain apparently healthy. We were also unable to transmit this seropositivity to an SRV-negative macaque by using inoculation of whole blood from subject 1. The results of this study provide evidence that occupational exposure to NHPs may increase the risk of infection with SRV and underscore the importance of both occupational safety practices and efforts to eliminate this virus from established macaque colonies.
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Zhang, Jingxuan, Xiangjun Liu, Xiaochen Wei, Lixi Liang, Jian Xiong, and Wei Li. "Uncertainty Analysis of Factors Influencing Stimulated Fracture Volume in Layered Formation." Energies 12, no. 23 (November 22, 2019): 4444. http://dx.doi.org/10.3390/en12234444.
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Hydraulic fracture dimension is one of the key parameters affecting stimulated porous media. In actual fracturing, plentiful uncertain parameters increase the difficulty of fracture dimension prediction, resulting in the difficulty in the monitoring of reservoir productivity. In this paper, we established a three-dimensional model to analyze the key factors on the stimulated reservoir volume (SRV), with the response surface method (RSM). Considering the rock properties and fracturing parameters, we established a multivariate quadratic prediction equation. Simulation results show that the interactions of injection rate (Q), Young’s modulus (E) and permeability coefficient (K), and Poisson’s ratio (μ) play a relatively significant role on SRV. The reservoir with a high Young’s modulus typically generates high pressure, leading to longer fractures and larger SRV. SRV reaches the maximum value when E1 and E2 are high. SRV is negatively correlated with K1. Moreover, maintaining a high injection rate in this layered formation with high E1 and E2, relatively low K1, and μ1 at about 0.25 would be beneficial to form a larger SRV. These results offer new perceptions on the optimization of SRV, helping to improve the productivity in hydraulic fracturing.
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Wang, Jiahang, Xiaodong Wang, and Wenxiu Dong. "A Semianalytical Model for Multiple-Fractured Horizontal Wells with SRV in Tight Oil Reservoirs." Geofluids 2017 (2017): 1–15. http://dx.doi.org/10.1155/2017/2632896.
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The paper developed a new semianalytical model for multiple-fractured horizontal wells (MFHWs) with stimulated reservoir volume (SRV) in tight oil reservoirs by combining source function theory with boundary element idea. The model is first validated by both analytical and numerical model. Then new type curves are established. Finally, the effects of SRV shape, SRV size, SRV permeability, and parameters of hydraulic fractures are discussed. Results show that SRV has great influence on the pressure response of MFHWs; the parameters of fractures, such as fracture distribution, length, and conductivity, also can affect the transient pressure of MFHWs. One novelty of this model is to consider the nonlinear flow around hydraulic fracture tips. The other novelty is the ability to model the shape of the SRV, production behavior of different fractures, and interfaces. Compared to numerical and analytic methods, this model can not only reduce extensive computing processing but also show high accuracy.
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Saepuloh, Uus, Diah Iskandriati, Joko Pamungkas, Dedy Duryadi Solihin, Sela Septima Mariya, and Dondin Sajuthi. "Construction of A Preliminary Three-Dimensional Structure Simian betaretrovirus Serotype-2 (SRV-2) Reverse Transcriptase Isolated from Indonesian Cynomolgus Monkey." Tropical Life Sciences Research 31, no. 3 (October 15, 2020): 47–61. http://dx.doi.org/10.21315/tlsr2020.31.3.4.
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Simian betaretrovirus serotype-2 (SRV-2) is an important pathogenic agent in Asian macaques. It is a potential confounding variable in biomedical research. SRV-2 also provides a valuable viral model compared to other retroviruses which can be used for understanding many aspects of retroviral-host interactions and immunosuppression, infection mechanism, retroviral structure, antiretroviral and vaccine development. In this study, we isolated the gene encoding reverse transcriptase enzyme (RT) of SRV-2 that infected Indonesian cynomolgus monkey (Mf ET1006) and predicted the three dimensional structure model using the iterative threading assembly refinement (I-TASSER) computational programme. This SRV-2 RT Mf ET1006 consisted of 547 amino acids at nucleotide position 3284–4925 of whole genome SRV-2. The polymerase active site located in the finger/palm subdomain characterised by three conserved catalytic aspartates (Asp90, Asp165, Asp166), and has a highly conserved YMDD motif as Tyr163, Met164, Asp165 and Asp166. We estimated that this SRV-2 RT Mf ET1006 structure has the accuracy of template modelling score (TM-score 0.90 ± 0.06) and root mean square deviation (RMSD) 4.7 ± 3.1Å, indicating that this model can be trusted and the accuracy can be seen from the appearance of protein folding in tertiary structure. The superpositionings between SRV-2 RT Mf ET1006 and Human Immunodeficiency Virus-1 (HIV-1) RT were performed to predict the structural in details and to optimise the best fits for illustrations. This SRV-2 RT Mf ET1006 structure model has the highest homology to HIV-1 RT (2B6A.pdb) with estimated accuracy at TM-score 0.911, RMSD 1.85 Å, and coverage of 0.953. This preliminary study of SRV-2 RT Mf ET1006 structure modelling is intriguing and provide some information to explore the molecular characteristic and biochemical mechanism of this enzyme.
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Rosenblum, Lisa L., Robin A. Weiss, and Myra O. McClure. "Virus Load and Sequence Variation in Simian Retrovirus Type 2 Infection." Journal of Virology 74, no. 8 (April 15, 2000): 3449–54. http://dx.doi.org/10.1128/jvi.74.8.3449-3454.2000.
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ABSTRACT The natural history of type D simian retrovirus (SRV) infection is poorly characterized in terms of viral load, antibody status, and sequence variation. To investigate this, blood samples were taken from a small cohort of mostly asymptomatic cynomolgus macaques (Macaca fascicularis), naturally infected with SRV type 2 (SRV-2), some of which were followed over an 8-month period with blood taken every 2 months. Provirus and RNA virus loads were obtained, the samples were screened for presence of antibodies to SRV-2 and neutralizing antibody titers to SRV-2 were assayed. env sequences were aligned to determine intra- and intermonkey variation over time. Virus loads varied greatly among cohort individuals but, conversely, remained steady for each macaque over the 8-month period, regardless of their initial levels. No significant sequence variation was found within an individual over time. No clear picture emerged from these results, which indicate that the variables of SRV-2 infection are complex, differ from those for lentivirus infection, and are not distinctly related to disease outcome.
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Kim, Kyung-Min, Joo-Sung Kim, Jeonghoon Oh, and Dustin R. Grooms. "Stroboscopic Vision as a Dynamic Sensory Reweighting Alternative to the Sensory Organization Test." Journal of Sport Rehabilitation 30, no. 1 (January 1, 2021): 166–72. http://dx.doi.org/10.1123/jsr.2019-0466.
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Context: The sensory organization test (SOT) is a standard for quantifying sensory dependence via sway-referenced conditions (sway-referenced support and sway-referenced vision [SRV]). However, the SOT is limited to expensive equipment. Thus, a practical version of the SOT is more commonly employed—the clinical test for sensory integration in balance; however, it fails to induce postural instability to the level of SRV. Objective: Determine if Stroboscopic vision (SV), characterized by intermittent visual blocking, may provide an alternative to the SRV for assessing postural stability. Design: Descriptive laboratory study. Setting: Research laboratory. Participants: Eighteen participants (9 males, 9 females; age = 22.1 [2.1] y, height = 169.8 [8.5] cm, weight = 66.5 [10.6] kg). Intervention: Participants completed the SOT conditions, and then repeated SOT conditions 2 and 5 with SV created by specialized eyewear. Main Outcome Measures: A repeated-measures analysis of variance was completed on the time-to-boundary metrics of center-of-pressure excursion in the anteroposterior and mediolateral directions in order to determine the difference between the full-vision, SV, and SRV conditions. Results: Postural stability with either SRV or SV was significantly worse than with full vision (P < .05), with no significant difference between SV and SRV (P > .05). Limits of agreement analysis revealed similar effects of SV and SRV except for unstable surface mediolateral time-to-boundary. Conclusions: In general, SV was found to induce a degree of postural instability similar to that induced by SRV, indicating that SV could be a portable and relatively inexpensive alternative for the assessment of sensory dependence and reweighting.
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Carman, Odang, Aulia Saputra, Alimuddin Alimuddin, Maskur Maskur, Dian R. Herdianto, Ratu Siti Aliah, Komar Sumantadinata, and Tristiana Yuniarti. "PERFORMA IKAN NILA (Oreochromis niloticus) HASIL SEX REVERSAL, GENETICALLY MALE DAN YY PADA FASE PENDEDERAN PERTAMA." Jurnal Riset Akuakultur 4, no. 1 (November 28, 2016): 33. http://dx.doi.org/10.15578/jra.4.1.2009.33-38.
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Penelitian ini dilakukan untuk mengkaji performa ikan nila hasil sex reversal (SRV), genetically male tilapia (GMT), dan YY pada fase pendederan pertama di akuarium. Benih ikan dipelihara selama 22 hari, dari umur 6 hari hingga 28 hari. Parameter yang diamati meliputi tingkat sintasan, persentase ikan jantan, laju pertumbuhan, dan biomassa. Hasil penelitian menunjukkan bahwa tingkat sintasan tidak berbeda (P>0,05) antar ketiga kelompok ikan dan kontrol (KN), berkisar antara 85,30%--86,20%. Persentase ikan jantan antara SRV (94,5% ± 1,32%) vs. GMT (93,8% ± 1,25%) dan GMT vs. YY (90,2% ± 1,83%) tidak berbeda (P>0,05), sedangkan antara SRV lebih tinggi daripada YY (P<0,05). Persentase ikan jantan pada ketiga kelompok ikan tersebut lebih tinggi (P<0,05) dibandingkan dengan KN (56,9% ± 3,62%). Pertumbuhan ikan YY dan GMT lebih cepat (P<0,05) dibandingkan dengan ikan SRV dan kontrol (KN). Bobot rata-rata ikan YY pada akhir penelitian mencapai 485 mg, ikan GMT 456 mg, ikan SRV 379 mg dan kontrol 342 mg. Produksi biomassa ikan YY, GMT, dan SRV masing-masing sebesar 41,3%; 32,9%; dan 10,3% lebih tinggi dibandingkan dengan KN. Dengan performa yang tinggi dan pertimbangan teknis di lapangan, benih GMT merupakan alternatif yang baik untuk dibudidayakan dalam rangka meningkatkan produksi ikan nila.The experiment was conducted to determine the performance of sex reversed (SRV), genetically male tilapia (GMT), and YY tilapia on first nursery phase in aquarium. Fry were reared for 22 days, from 6 to 28 days-old. Survival rate, percentage of male fish, growth rate and biomass were observed. The result of the study showed that survival rate among fish group and control were similar (P>0.05), ranged from 85.30%-86.20%. Percentage of male fish between SRV (94.5% ± 1.32%) versus GMT (93.8% ± 1.25%) and GMT versus YY (90.2% ± 1.83%) were also similar (P>0.05), while SRV is higher than YY (P<0.05). Percentage of male fish in the three fish groups was higher than that of control (56.9% ± 3.62%). Growth of YY fish and GMT were higher compared to SRV and control fish (KN). The mean weight of YY fish at the end of the experiment reached 476 mg, GMT fish 447 mg, SRV fish 379 mg and control 342 mg. Biomass of YY, GMT and SRV fish were respectively higher by 41.3%, 32.9%, and 10.3% compared to control. With high performance and technical consideration in farm, GMT fish can be a potential alternative to be cultured in fish farm in order to increase aquaculture production of nile tilapia.
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Chang, Haibin, and Dongxiao Zhang. "History Matching of Stimulated Reservoir Volume of Shale-Gas Reservoirs Using an Iterative Ensemble Smoother." SPE Journal 23, no. 02 (November 10, 2017): 346–66. http://dx.doi.org/10.2118/189436-pa.
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Summary Economic production from shale-gas reservoirs typically relies on the drilling of horizontal wells and hydraulic fracturing in multiple stages. In addition to the creation of hydraulic fractures, hydraulic-fracturing treatment can also reopen existing natural fractures, which can create a complex-fracture network. The area that is covered by the fracture network is usually termed the stimulated reservoir volume (SRV), and the spatial extent and properties of the SRV are crucial for shale-gas-production behavior. In this work, we propose a method for history matching of the SRV of shale-gas reservoirs using production data. For each hydraulic-fracturing stage, the fracture network is parameterized with one major fracture of the hydraulic fractures and the SRV that represents minor hydraulic fractures and reopened natural fractures. The major fracture is modeled explicitly, whereas the SRV is modeled by the dual-permeability/dual-porosity (DP/DP) model. Moreover, the spatial extent of the SRV is parameterized by the level-set-function values on a predefined representing-node system. After parameterization, an iterative ensemble smoother is used to perform history matching. Both single-stage-fracturing cases and multistage-fracturing cases are set up to test the performance of the proposed method. Numerical results demonstrate that by use of the proposed method, the SRV can be well-recognized by assimilating production data.
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Sionov, Ronit Vogt, Irith Gati, David Kirmayer, Michael Friedman, Doron Steinberg, and Menachem Gross. "Voice Prosthesis Coated with Sustained Release Varnish Containing Clotrimazole Shows Long-Term Protection against Candida albicans: An In Vitro Study." Molecules 26, no. 17 (September 5, 2021): 5395. http://dx.doi.org/10.3390/molecules26175395.
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Fungal biofilm formation on voice prosthesis (VP) is a major health problem that requires repeated replacement of the prosthesis. Candida albicans is one of the pathogens that frequently inhabits the VP. We proposed that coating VPs with sustained-release varnish (SRV) containing clotrimazole (CTZ) might prevent fungal biofilm formation. The long-term antifungal activities of SRV-CTZ- versus SRV-placebo-coated VPs was tested daily by measuring the inhibition zone of C. albicans seeded on agar plates or by measuring the fungal viability of C. albicans in suspension. The extent of biofilm formation on coated VPs was analyzed by confocal microscopy and scanning electron microscopy. We observed that SRV-CTZ-coated VPs formed a significant bacterial inhibition zone around the VPs and prevented the growth of C. albicans in suspension during the entire testing period of 60 days. Fungal biofilms were formed on placebo-coated VPs, while no significant biofilms were observed on SRV-CTZ-coated VPs. HPLC analysis shows that CTZ is continuously released during the whole test period of 60 days at a concentration above the minimal fungistatic concentration. In conclusion, coating VPs with an SRV-CTZ film is a potential effective method for prevention of fungal infections and biofilm formation on VPs.
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Barracano, Rosaria, Margarita Brida, Silvia Guarguagli, Rosalinda Palmieri, Gerhard Paul Diller, Michael A. Gatzoulis, and Tom Wong. "Implantable cardiac electronic device therapy for patients with a systemic right ventricle." Heart 106, no. 14 (April 8, 2020): 1052–58. http://dx.doi.org/10.1136/heartjnl-2019-316202.
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The systemic right ventricle (SRV), defined as the morphological right ventricle supporting the systemic circulation, is relatively common in congenital heart disease (CHD). Our review aimed at examining the current evidence, knowledge gaps and technical considerations regarding implantable cardiac electronic device therapy in patients with SRV. The risk of sinus node dysfunction (SND) after atrial switch repair and/or complete heart block in congenitally corrected transposition of great arteries requiring permanent pacing increases with age. Similar to acquired heart disease, indication for pacing includes symptomatic bradycardia, SND and high degree atrioventricular nodal block. Right ventricular dysfunction and heart failure also represent important complications in SRV patients. Cardiac resynchronisation therapy (CRT) has been proposed to improve systolic function in SRV patients, although indications for CRT are not well defined and its potential benefit remains uncertain. Amongst adult CHD, patients with SRV are at the highest risk for sudden cardiac death (SCD). Nevertheless, risk stratification for SCD is scarce in this cohort and implantable cardioverter-defibrillator indication is currently limited to secondary prevention. Vascular access and the incidence of device-related complications, such as infections, inappropriate shocks and device system failure, represent additional challenges to implantable cardiac electronic device therapy in patients with SRV. A multidisciplinary approach with tertiary expertise and future collaborative research are all paramount to further the care for this challenging nonetheless ever increasing cohort of patients.
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Wisotsky, Sadie R., Sergei L. Kosakovsky Pond, Stephen D. Shank, and Spencer V. Muse. "Synonymous Site-to-Site Substitution Rate Variation Dramatically Inflates False Positive Rates of Selection Analyses: Ignore at Your Own Peril." Molecular Biology and Evolution 37, no. 8 (February 18, 2020): 2430–39. http://dx.doi.org/10.1093/molbev/msaa037.
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Abstract Most molecular evolutionary studies of natural selection maintain the decades-old assumption that synonymous substitution rate variation (SRV) across sites within genes occurs at levels that are either nonexistent or negligible. However, numerous studies challenge this assumption from a biological perspective and show that SRV is comparable in magnitude to that of nonsynonymous substitution rate variation. We evaluated the impact of this assumption on methods for inferring selection at the molecular level by incorporating SRV into an existing method (BUSTED) for detecting signatures of episodic diversifying selection in genes. Using simulated data we found that failing to account for even moderate levels of SRV in selection testing is likely to produce intolerably high false positive rates. To evaluate the effect of the SRV assumption on actual inferences we compared results of tests with and without the assumption in an empirical analysis of over 13,000 Euteleostomi (bony vertebrate) gene alignments from the Selectome database. This exercise reveals that close to 50% of positive results (i.e., evidence for selection) in empirical analyses disappear when SRV is modeled as part of the statistical analysis and are thus candidates for being false positives. The results from this work add to a growing literature establishing that tests of selection are much more sensitive to certain model assumptions than previously believed.
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Xu, Tao, Mingyang Zhai, Bo Huang, Liaoyuan Zhang, Aishan Li, Quansheng Zhang, Zilin Zhang, Lei Wang, and Lianchong Li. "Numerical Analysis of Multiple Factors Affecting Hydraulic Fracturing in Heterogeneous Reservoirs Using a Coupled Hydraulic-Mechanical-Damage Model." Geofluids 2021 (April 14, 2021): 1–20. http://dx.doi.org/10.1155/2021/5552287.
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Hydraulic fracturing performance, affected by multiple factors, was essential to the economic exploitation of oil and gas in heterogeneous unconventional reservoirs. Multifactor analysis can gain insight into the fracturing response of reservoirs and in turn optimize the treatment design. Based on characterizations of the geological setting of a heterogeneous glutenite reservoir, the hydraulic fracture (HF) initiation and propagation process, as well as the stimulated reservoir volume (SRV), were simulated and analyzed using a coupled hydraulic-mechanical-damage model. The Weibull distribution was employed to describe rock heterogeneity. The numerical model was verified with microseism (MS) interpretation results of HF geometry. A multifactor analysis and optimization workflow integrating response surface methodology, central composite design (CCD), and numerical simulations was proposed to investigate the coupling effects of multiple geomechanical and hydrofracturing factors on SRV and identify the optimum design of fracturing treatment. The results showed that the horizontal stress difference and injection rate were the most significant factors to control the SRV. Increasing the injection rate and reducing fluid viscosity may contribute to improving the SRV. It is more difficult to increase the SRV at higher horizontal stress difference than at lower horizontal stress difference. The multifactor analysis and optimization workflow introduced in this work was a practical and effective method to control the HF geometry and improve the SRV. This study provided a deep understanding of the hydraulic fracturing mechanism and possessed theoretical significance for treatment design.
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Sun, Qi Ming, Alexander Melnikov, Andreas Mandelis, and Robert Pagliaro. "Surface Recombination Velocity Imaging of HF-Etched Si Wafers Using Dynamic Heterodyne Lock-In Carrierography." Solid State Phenomena 282 (August 2018): 13–18. http://dx.doi.org/10.4028/www.scientific.net/ssp.282.13.
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Surface electronic quality of wet-cleaned Si wafers was characterized quantitatively and all-optically via spatially-resolved surface recombination velocity (SRV) imaging using InGaAs-camera-based dynamic heterodyne lock-in carrierography. Six samples undergone four different hydrofluoric special-solution etching conditions were tested, their SRV distributions at different queue times after the hydrogen passivation processes were obtained, and a quantitative assessment of their surface electronic quality was made based on the evolution behavior of globally-integrated information from the SRV images. The data acquisition time for an SRV image with full camera pixel resolution was about 3 min. The methodology introduced here is promising for in-line nondestructive testing/evaluation and quality control at different fabrication/manufacturing stages in the electronic industry. Keywords: heterodyne lock-in carrierography, surface recombination velocity, quantitative imaging, HF etching, Si wafers
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Lin, Avi, and Jianfu Ma. "Stimulated-Rock Characteristics and Behavior in Multistage Hydraulic-Fracturing Treatment." SPE Journal 20, no. 04 (August 20, 2015): 784–89. http://dx.doi.org/10.2118/167716-pa.
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Summary This paper presents a mathematical integration process through which all the important useful information and data related to stimulated rock are properly extracted and embedded so that the total effects of the hydraulic-fracturing stimulation are properly presented by the microseismic data detected and collected during the hydraulic-fracturing process. A multistage hydraulic-fracturing strategy is often used to help maximize the stimulated reservoir volume (SRV). The current analysis is based on chaining the stage results one-by-one. At each stage, the 3D SRV is constructed on the basis of its observed microseismic events with an enhanced convex-hull approach. This algorithm offers both a mathematical approximation of 3D volume and a 3D visualization of the SRV geophysical shape(s). More-detailed geometric characteristics are calculated further from the ellipsoid that best fits the constructed SRV, which relies on the acquired microseismic events. The characteristics include length, width, height, and orientation azimuth of the stimulated rock. Moreover, it forms the basis for calculating the overall SRV with the stage-by-stage approach. In the advanced phase, this algorithm offers characteristics related to the interaction between multiple stages. The accurate 3D geophysical geometry of the overlapping volume between multiple stages is extracted and is calculated, and the percentage of overlapping volume over the SRV is estimated at each stage. These volume-overlapping quantities reveal the potential communication between these stages, indicating the efficiency of hydraulic-fracturing efforts and implying the loss of treatment fluid. This algorithm provides the field engineers with several useful aspects: an essential, reliable, and direct compound tool to dynamically visualize the stimulated reservoir geometry and treatment-field evolution; a real-time evaluation of the efficiency of a hydraulic-fracturing treatment; and parameters to help increase the production of a stimulated reservoir.
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Cheng, Lin Lin, Yuan Fang Cheng, Chong Chen, Dong Feng Zhu, and Wen Biao Deng. "Study on the Feasibility of SRV in Coal Reservoir." Advanced Materials Research 986-987 (July 2014): 734–37. http://dx.doi.org/10.4028/www.scientific.net/amr.986-987.734.
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In our country there is plenty of CBM (coalbed methane), but the state of CBM itself, unique output mechanism and low saturation, low permeability, low reservoir pressure and high gas content, et al. determine the low efficiency of it, so in order to improve CBM recovery, combined with the successful experience of north American shale gas reservoir by SRV(stimulated reservoir volume), the writer summarizes the implementation of SRV, deeply analyzes effectiveness and limitations of this new technology in CBM development. The results of practical research and theoretical analysis show that SRV in the coal reservoir can achieve the desired effect on the condition that there are great quantity of natural fractures, joints and bedding, weak structure surface development in the reservoir, the rock brittleness index is greater than 40 and horizontal principal stress difference is relatively smaller. Finally, simulating a well’s condition by the MEYER software, the result shows that SRV is feasible in coal reservoir, which will create important guiding significance and practical value for the exploration of CBM.
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Jiang, Ruizhong, Jianchun Xu, Zhaobo Sun, Chaohua Guo, and Yulong Zhao. "Rate Transient Analysis for Multistage Fractured Horizontal Well in Tight Oil Reservoirs considering Stimulated Reservoir Volume." Mathematical Problems in Engineering 2014 (2014): 1–11. http://dx.doi.org/10.1155/2014/489015.
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A mathematical model of multistage fractured horizontal well (MsFHW) considering stimulated reservoir volume (SRV) was presented for tight oil reservoirs. Both inner and outer regions were assumed as single porosity media but had different formation parameters. Laplace transformation method, point source function integration method, superposition principle, Stehfest numerical algorithm, and Duhamel’s theorem were used comprehensively to obtain the semianalytical solution. Different flow regimes were divided based on pressure transient analysis (PTA) curves. According to rate transient analysis (RTA), the effects of related parameters such as SRV radius, storativity ratio, mobility ratio, fracture number, fracture half-length, and fracture spacing were analyzed. The presented model and obtained results in this paper enrich the performance analysis models of MsFHW considering SRV.
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Ramírez Santoyo, Luis Felipe, Julio Muro Erreguerena, and Fidel René Díaz Serrano. "Efecto de diferentes concentraciones de potasio en parámetros de calidad en jitomate hidropónico." Acta Universitaria 21, no. 1 (April 1, 2011): 5–10. http://dx.doi.org/10.15174/au.2011.44.
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El manejo de las relaciones iónicas en la solución nutritiva con la hipótesis de que el potasio puede mejorar la calidad del jitomate, por la influencia de la síntesis de carotenoides de los frutos de jitomate fue el principal propósito de este trabajo. Se realizaron dos experimentos con el hibrido ‘Gabriela’ en un sistema de cultivo sin suelo dentro de un invernadero de tecnología intermedia. En la etapa vegetativa se aplicó una solución estándar (SS) y en la etapa reproductiva se aplicaron soluciones con diferentes concentraciones de potasio (K) (SR1 (20 % K), SR2 (40 % K), SR3 (60 % K) y SR4 (45 % K)); el porcentaje de potasio se refiere al porcentaje de K respecto del porcentaje total de cationes. Todas las soluciones nutritivas tuvieron una concentración iónica total de 30 mg L-1 un valor de pH 6.5, y 3 dS m-1 de conductividad eléctrica aproximadamente. En el primer experimento, se probaron tres tratamientos (SR1, SR2 y SR3) con ocho repeticiones. En el segundo experimento, se utilizaron dos tratamientos (SR2 y SR4) con dieciséis repeticiones. El tratamiento SR4 sobrepasó significativamente a SR2 en todos los parámetros de calidad, excepto en β-caroteno y pH para cada uno de los racimos seleccionados (1°, 3°, 5°, 7° y 9°). La concentración de potasio afectó significativamente la concentración de sustancias nutraceúticas tales como el licopeno y β-caroteno, mismas que pueden utilizarse como indicadores de la calidad interna del jitomate, como lo demostraron los datos analíticos y de evaluación sensorial practicada.
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Dare, Richard A. "Seasonal Tropical Cyclone Rain Volumes over Australia." Journal of Climate 26, no. 16 (August 6, 2013): 5958–64. http://dx.doi.org/10.1175/jcli-d-12-00778.1.
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Abstract For a continent as dry as Australia, where water is a valuable resource, it is important to understand the sources of rainfall. The volume of water contributed by tropical cyclones (TCs) during the November–April season is investigated using 42 seasons of TC and rainfall data. The seasonal total TC rain volume (SRV) ranges from a minimum of 34.2 km3 in 1987/88 to a maximum of 564.4 km3 in 2000/01, with a long-term mean of 198.6 ± 107.4 km3. In terms of mean percentage, TCs contribute 7.6% to the seasonal total rain volume over Australia. The number of landfalling TCs and the number of TCs that individually produce more than the mean individual TC rain volume (25.7 km3) during a season are significant influences on the SRV. The TCs passing near the coast without landfalling have little impact on the SRV. The two parameters that correlate best with SRV are the total time spent over land by TCs during a season and the total land area covered by TCs during a season (correlation coefficients of 0.79 and 0.84, respectively). Although the highest SRVs occur almost exclusively during La Niña and neutral seasons, there is a mixture of ENSO seasons corresponding to the lowest SRVs. In general, the large interannual variability, even within a particular ENSO class, indicates that caution should be used when attempting to relate SRV to the phase of ENSO.
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Wu, Jianfa, Jian Zhang, Cheng Chang, Weiyang Xie, and Tianpeng Wu. "A Model for a Multistage Fractured Horizontal Well with Rectangular SRV in a Shale Gas Reservoir." Geofluids 2020 (December 5, 2020): 1–18. http://dx.doi.org/10.1155/2020/8845250.
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Although great success has been achieved in the shale gas industry, accurate production dynamic analyses is still a challenging task. Long horizontal wells coupling with mass hydraulic fracturing has become a necessary technique to extract shale gas efficiently. In this paper, a comprehensive mathematical model of a multiple fractured horizontal well (MFHW) in a rectangular drainage area with a rectangular stimulated reservoir volume (SRV) has been established, based on the conceptual model of “tri-pores” in shale gas reservoirs. Dimensionless treatment and Laplace transformation were employed in the modeling process, while the boundary element method was used to solve the mathematical model. The Stehfest numerical inversion method and computer programing techniques were employed to obtain dimensionless type curves, production rate, and cumulative production. Results suggest that 9 flow stages can be observed from the pseudopressure derivative type curve when the reservoir and the SRV are large enough. The number of fractures, SRV permeability, and reservoir permeability have no effect on the total production when the well is abandoned. As SRV and reservoir permeability increases, the production rate is much higher in the middle production stage. Although the SRV scale and its permeability are very important for early and intermediate production rates, the key factors restricting the shale gas production rate are the properties of the shale itself, such as adsorbed gas content, natural fractures, and organic content. The proposed model is useful for analyzing production dynamics with stimulated horizontal wells in shale gas reservoirs.
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Ladouceur, Magalie, Teresa Segura de la Cal, Bamba Gaye, Eugenie Valentin, Reaksmei Ly, Laurence Iserin, Antoine Legendre, et al. "Effect of medical treatment on heart failure incidence in patients with a systemic right ventricle." Heart 107, no. 17 (May 6, 2021): 1384–89. http://dx.doi.org/10.1136/heartjnl-2020-318787.
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BackgroundTo date, clinical trials have been underpowered to demonstrate a benefit from ACE inhibitors (ACEis) or angiotensin II receptor blockers (ARBs) in preventing systemic right ventricle (sRV) failure and disease progression in patients with transposition of the great arteries (TGA). This observational study aimed to estimate the effect of ACEi and ARB on heart failure (HF) incidence and mortality in a large population of patients with an sRV.MethodsData on all patients with an sRV under active follow-up at two tertiary centres between January 2007 and September 2018 were studied. The effect of ACEi and ARB on the incidence of HF and mortality was estimated using a propensity score weighting approach to control confounding.ResultsAmong the 359 patients with an sRV (32.2 (IQR 26.4–38.3) years, 59.3% male, 66% complete TGA with atrial switch repair and 34% congenitally corrected TGA), 79 (22%) had a moderate to severe sRV dysfunction and 138 (38%) were treated with ACEi or ARB. Fourteen (3.6%) patients died, 8 (2.1%) underwent heart transplantation and 46 (11.8%) had a new HF event over a median follow-up of 7.1 (IQR 4.0–9.4) years. On multivariate Cox analysis with adjustment using propensity score weighting approaches, ACEi or ARBs treatment was not significantly associated with a lower HF incidence or mortality in patients with an sRV.ConclusionsDespite significant neurohormonal activation described in patients with an sRV, there is still no evidence of a beneficial effect of ACEi or ARB on morbidity and mortality in this population.
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Kumar, Pawan, Peter Hodgson, Hossein Beladi, Amit Roy Chowdhury, Mamookho Elizabeth Makhatha, and Aniket K. Dutt. "Restoration Mechanism and Sub-Structural Characteristics of Duplex Stainless Steel with an Initial Equiaxed Austenite Morphology during Post-Deformation Annealing." Key Engineering Materials 882 (April 2021): 64–73. http://dx.doi.org/10.4028/www.scientific.net/kem.882.64.
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Uni-axial compression (UAC) tests and further post deformation annealing (PDA) were done for 23Cr-6Ni-3Mo duplex stainless steel (DSS). The initial morphology was equiaxed (EQ) in nature. In the first stage of PDA, austenite showed limited static recrystallization (SRX) followed by static recovery (SRV); however ferrite showed static recovery (SRV). In the second stage of PDA, the austenite showed grain coarsening followed by disintegration of substructures (DIS); and ferrite revealed mostly SRV leading to grain coarsening. The third stage of PDA envisages substructural disintegration of unstable substructure leading to saturation in both austenite and ferrite. The sub-structural characteristics were provided by Electron backscattered diffraction (EBSD) and its post processing were done by using HKL Channel 5 software.
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Nassir, M., A. Settari, and R. Wan. "Prediction of Stimulated Reservoir Volume and Optimization of Fracturing in Tight Gas and Shale With a Fully Elasto-Plastic Coupled Geomechanical Model." SPE Journal 19, no. 05 (March 10, 2014): 771–85. http://dx.doi.org/10.2118/163814-pa.
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Summary Hydraulic fracturing is essential for the economic development of tight gas reservoirs and shale-gas reservoirs. Current techniques are unable to predict the stimulated-reservoir-volume (SRV) dependence on fracturing-job and rock-mechanics parameters, which precludes any meaningful optimization. In the authors' previous work on the SRV-propagation prediction, the combined tensile/shear fracturing model applied to the fracturing of tight gas formations has shown the creation of a relatively narrow, focused SRV that resembled behavior dominated by a single fracture. In this work, the model has been significantly improved by the implementation of a rigorous full Newton elasto-plastic solution of the geomechanics of rock containing induced fractures. The results reveal interesting features of complex-fracture propagation in tight formations, which are in broad agreement with the shapes of SRVs obtained from microseismic imaging. The developed code is flexible enough to allow either tensile or shear fracturing or the occurrence of both to be examined on the basis of initial reservoir conditions. Different cases of 2D and 3D simulations will be presented that demonstrate some important features of the process. First, it is found that a wide SRV can result in cases in which initial reservoir conditions are close to the shear-fracturing point, such as in formations with microfractures, partially cemented natural fractures, and abnormally high initial pore pressure. Second, the SRV width is found to depend on the horizontal stress contrast, as expected. Third, wide SRV growth is associated with constant or increasing pumping pressure necessary for further failed-zone growth as a result of the loss of elastic coupling by off-planar failure propagation. Further, under high injection pressure, an efficient fracture elasto-plastic constitutive model developed can drive both maximal and minimal effective stresses to zero or tensile, and, therefore, the creation of tensile fracturing can be predicted simultaneously with shear fracturing. This will then provide a means of modeling proppant transport. The new model is a significant step toward the development of an integrated predictive tool for the optimization of shale-gas development.
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Blakely, Thomas J., and Gregory M. Dziadosz. "Social Role Theory and Social Role Valorization for Care Management Practice." Care Management Journals 16, no. 4 (December 2015): 184–87. http://dx.doi.org/10.1891/1521-0987.16.4.184.
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This article proposes that social role theory (SRT) and social role valorization (SRV) be established as organizing theories for care managers. SRT is a recognized sociological theory that has a distinctive place in care management practice. SRV is an adjunct for SRT that focuses on people who are devalued by being in a negative social position and supports behavior change and movement to a valued social position.
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Kaul, Artur, Uwe Schönmann, and Stefan Pöhlmann. "Seroprevalence of viral infections in captive rhesus and cynomolgus macaques." Primate Biology 6, no. 1 (March 26, 2019): 1–6. http://dx.doi.org/10.5194/pb-6-1-2019.
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Abstract. Macaques serve as important animal models for biomedical research. Viral infection of macaques can compromise animal health as well as the results of biomedical research, and infected animals constitute an occupational health risk. Therefore, monitoring macaque colonies for viral infection is an important task. We used a commercial chip-based assay to analyze sera of 231 macaques for the presence of antibody responses against nine animal and human viruses. We report high seroprevalence of cytomegalovirus (CMV), lymphocryptovirus (LCV), rhesus rhadinovirus (RRV) and simian foamy virus (SFV) antibodies in all age groups. In contrast, antibodies against simian retrovirus type D (SRV/D) and simian T cell leukemia virus (STLV) were detected only in 5 % and 10 % of animals, respectively, and were only found in adult or aged animals. Moreover, none of the animals had antibodies against herpes B virus (BV), in keeping with the results of in-house tests previously used for screening. Finally, an increased seroprevalence of measles virus antibodies in animals with extensive exposure to multiple humans for extended periods of time was observed. However, most of these animals were obtained from external sources, and a lack of information on the measles antibody status of the animals at the time of arrival precluded drawing reliable conclusions from the data. In sum, we show, that in the colony studied, CMV, LCV, RRV and SFV infection was ubiquitous and likely acquired early in life while SRV/D and STLV infection was rare and likely acquired during adulthood.
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Wang, Guangdong, Ailin Jia, Yunsheng Wei, and Cong Xiao. "Transient Pressure Analysis for Multifractured Horizontal Well with the Use of Multilinear Flow Model in Shale Gas Reservoir." Geofluids 2020 (February 7, 2020): 1–20. http://dx.doi.org/10.1155/2020/8348205.
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Shale gas reservoirs (SGR) have been a central supply of carbon hydrogen energy consumption and hence widely produced with the assistance of advanced hydraulic fracturing technologies. On the one hand, due to the inherent ultralow permeability and porosity, there is stress sensitivity in the reservoirs generally. On the other hand, hydraulic fractures and the stimulated reservoir volume (SRV) generated by the massive hydraulic fracturing operation have contrast properties with the original reservoirs. These two phenomena pose huge challenges in SGR transient pressure analysis. Limited works have been done to take the stress sensitivity and spatially varying permeability of the SRV zone into consideration simultaneously. This paper first idealizes the SGR to be four linear composite regions. What is more, the SRV zone is further divided into subsections on the basis of nonuniform distribution of proppant within the SRV zone which easily yields spatially varying permeability away from the main hydraulic fracture. By means of perturbation transformation and Laplace transformation, an analytical multilinear flow model (MLFM) is obtained and validated as a comparison with the previous models. The flow regimes are identified, and the sensitivity analysis of critical parameters is conducted to further understand the transient pressure behaviors. The research results provided by this work are of significance for an effective recovery of SGR resources.
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Encalada, Maria Asuncion Rojas, and Sonia Magali Arteaga Sarmiento. "Perceptions about Self-recording Videos to Develop EFL Speaking Skills in Two Ecuadorian Universities." Journal of Language Teaching and Research 10, no. 1 (January 1, 2019): 60. http://dx.doi.org/10.17507/jltr.1001.07.
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The present study explores the perceptions of EFL students from two Ecuadorian universities on the use of Self-Recording Videos (SRV) to develop speaking skills. As students do not have the opportunity to talk in the target language outside their classes, the authors of the present study analyzed the participants’ viewpoints regarding SRV to improve their conversational abilities. There is still limited research on the use of SRV for English speaking practice in a foreign country, so the researchers' purpose is to fill this gap in the literature to contribute to further studies on the topic. The authors consider essential to acknowledge the positive aspects of using this technique from the learners’ perspectives. For this purpose, participants were required to self-record a video related to the content of the class during the week and submit it to the Moodle platform.
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Habbous, Steven, Carlos Garcia-Ochoa, Gary Brahm, Chris Nguan, and Amit X. Garg. "Can Split Renal Volume Assessment by Computed Tomography Replace Nuclear Split Renal Function in Living Kidney Donor Evaluations? A Systematic Review and Meta-Analysis." Canadian Journal of Kidney Health and Disease 6 (January 2019): 205435811987545. http://dx.doi.org/10.1177/2054358119875459.
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Background: As part of their living kidney donor assessment, all living donor candidates complete a computed tomography (CT) angiogram, but some also receive a nuclear renogram for split renal function (SRF%). Objective: We considered whether split renal volume (SRV%) assessed by CT can predict SRF%. Design: Systematic review and meta-analysis. Setting: Living donor candidates undergoing evaluation as potential living kidney donors. Patients: Living donor candidates who received both a nuclear renogram for split function and CT for SRV as part of their living donor work-up. Measurements: Split renal volume from CT scans and SRF from nuclear renography. Methods: We performed a systematic review and meta-analysis of the literature, abstracting data and digitizing plots where possible. We searched Medline, EMBASE, and the Cochrane Library. We added data from donor candidates assessed in London, Ontario from 2013 to 2016. We used fixed and random-effects models to pool Fisher’s z-transformed Pearson’s correlation coefficient ( r). We conducted random-effects meta-regression on digitized and aggregate data. Studies were restricted to living kidney donors or living donor candidates. Results: After pooling 19 studies (n = 1479), we obtained a pooled correlation of r = 0.74 (95% confidence interval [CI] = 0.61-0.82). By linear regression using individual-level data, we observed a 0.76% (95% CI = 0.71-0.81) increase in SRF% for every 1% increase in SRV%. Split renal volume had a specificity of 88% for discriminating SRF at a threshold that could influence the decision of which kidney is to be removed (between-kidney difference ≥10%). Predonation SRV and SRF both moderately predicted kidney function 6 to 12 months after donation: r = 0.75 for SRV and r = 0.73 for SRF; Δ r = 0.05 (–0.02, 0.13). Limitations: Most studies were retrospective and measured SRV and SRF only on selected living donor candidates. Efficiency gains in removing the SRF from the evaluation will depend on the transplant program. Conclusion: Split renal volume has the potential to replace SRF for some candidates. However, it is uncertain whether it can do so reliably and routinely across different transplant centers. The impact on clinical decision-making needs to be assessed in well-designed prospective studies. Trial registration: The digitized data are registered with Mendeley Data (doi10.17632/dyn2bfgxxj.2).
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Chen, Qi, Shaojun Wang, Dan Zhu, Guoxuan Ren, Yuan Zhang, and Jinghong Hu. "A Comprehensive Model for Estimating Stimulated Reservoir Volume Based on Flowback Data in Shale Gas Reservoirs." Geofluids 2020 (September 9, 2020): 1–14. http://dx.doi.org/10.1155/2020/8886988.
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Stimulated reservoir volume (SRV) which is generated by horizontal drilling with multistage hydraulic fracturing governs the production in the shale gas reservoirs. Although microseismic data has been used to estimate the SRV, it is high-priced and sometimes overestimated. Additionally, the effect of stress sensitivity on SRV is not considered in abnormal overpressure areas. Thus, the objective of this work is to characterize subsurface fracture networks with stress sensitivity of permeability through the shale gas well production data of the early flowback stage. The flowback regions are first identified with the flowback data of two shale gas wells in South China. Then, we measured the permeability stress sensitivity of the core after fracturing, coupled to the dynamic relative permeability (DRP) calculation to obtain an accurate and simple DRP curve. After that, a comprehensive model is built considering dynamic two-phase relative permeability function and stress sensitivity. Finally, we compared the calculated results with the microseismic data. The results show that the proposed model could reasonably predict the SRV using the flowback data after fracturing. Additionally, compared with the microseismic data, the stress sensitivity should be included, especially in the abnormal overpressure block. It is believed that this mathematical model is accurate and useful. The work provides an efficient approach to estimate stimulated reservoir volume in the shale gas reservoirs.
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Huang, Xing Ling, and Xiang Bing Huang. "A Risk-Based Conceptual Design Method for Submarine Rescue Vehicle." Applied Mechanics and Materials 201-202 (October 2012): 477–82. http://dx.doi.org/10.4028/www.scientific.net/amm.201-202.477.
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In order to reduce the risks and uncertainties in conceptual design of submarine rescue vehicle (SRV), the paper proposed a risk-based conceptual design method, which consisted of three focus areas: problem setup, risk assessment, risk mitigation and decision support. Conventional risk assessment tools (e.g. probability risk assessment) were not suited for initial design because of lack of data, and a safety analysis model using fuzzy-logic approach employing fuzzy IF-THEN rules was introduced to carry out risk analysis in conceptual design. Subsequently, it was investigated that the main risky factors which influenced system risk in initial design were technology level of SRV, safety of SRV, task complexity, investment and repayment. And then a risk analysis model for submarine rescue vehicle was introduced. Lastly a case was studied to demonstrate the application of the model, and the results showed that it was an effective way to reduce the risks and uncertainties in conceptual design process.
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Paramastri, Y. A., J. M. Wallace, K. J. Salleng, L. M. Wilkinson, D. E. Malarkey, and J. M. Cline. "Intracranial Lymphomas in Simian Retrovirus-Positive Macaca fascicularis." Veterinary Pathology 39, no. 3 (May 2002): 399–402. http://dx.doi.org/10.1354/vp.39-3-399.
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Two young adult Macaca fascicularis each had unilateral mydriasis and ptosis. Both animals were euthanatized, monkey No. 1 for progressive neurologic signs and monkey No. 2 because of a positive intradermal tuberculin test. At necropsy, each animal had a single intracranial mass on the ventral surface of the midbrain, surrounding the oculomotor nerve. Histologically, both masses were immunoblastic lymphomas. Immunohistochemical staining revealed the neoplasms to be of B-cell origin. Simian retrovirus (SRV) was isolated from both monkeys, but simian immunodeficiency virus was not found. Both animals lacked antibody to SRV. Both animals had antibodies to Epstein-Barr-like virus (EBV), but EBV antigens were not found by immunohistochemistry. Polymerase chain reaction analysis for integrated EBV DNA was unproductive. One of the animals (monkey No. 2) had a pulmonary infection with Mycobacterium avium, suggesting that immunosuppression was present. These cases represent a unique and previously undescribed type of solitary lymphoma in SRV-infected macaques.
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Pinto, María, and Ramón A. Manso. "El uso de mapas conceptuales para la evaluación de los servicios de referencia virtual de las bibliotecas universitarias: una experiencia práctica." Investigación Bibliotecológica. Archivonomía, Bibliotecología e Información 26, no. 57 (October 8, 2012): 249. http://dx.doi.org/10.22201/iibi.0187358xp.2012.57.33846.
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La implantación de las tecnologías de la información proporciona a los servicios bibliotecarios cierto dinamismo en su concepción y desarrollo, como el caso del Servicio de Referencia Virtual (SRV), que además se debe evaluar con regularidad. El objetivo de este estudio es conocer la opinión de un grupo de profesionales, que trabajan en bibliotecas, participantes de clases sobre cómo ha de ser un SRV, qué elementos de calidad han de aportar y cuál ha de ser su proyección, desde un enfoque que contemple siempre al usuario como protagonista principal de dicho análisis. La metodología empleada es de corte cualitativo, basada en el uso del mapa conceptual como instrumento de diagnóstico y prospección a la vez que herramienta visual que permita observar y comparar gráficamente los criterios fundamentales aportados por los participantes en el análisis. Los resultados solicitan una mayor implicación del usuario, y la formación en habilidades informacionales desde el propio SRV.
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SU, YULIANG, GUANGLONG SHENG, WENDONG WANG, QI ZHANG, MINGJING LU, and LONG REN. "A MIXED-FRACTAL FLOW MODEL FOR STIMULATED FRACTURED VERTICAL WELLS IN TIGHT OIL RESERVOIRS." Fractals 24, no. 01 (March 2016): 1650006. http://dx.doi.org/10.1142/s0218348x16500067.
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Stimulated reservoir volume (SRV) with large fracture networks can be generated near hydraulic fractured vertical wells (HFVWs) in tight oil reservoirs. Statistics show that natural microfractures and fracture networks stimulated by SRV were self-similar in statistical sense. Currently, various analytical models have been presented to study pressure behaviors of HFVWs in tight oil reservoirs. However, most of the existing models did not take the distribution and self-similarity of fractures into consideration. To account for stimulated characteristic and self-similarity of fractures in tight oil reservoirs, a mixed-fractal flow model was presented. In this model, there are two distinct regions, stimulated region and unstimulated region. Dual-porosity model and single porosity model were used to model stimulated and unstimulated regions, respectively. Fractal geometry is employed to describe fractal permeability and porosity relationship (FPPR) in tight oil reservoirs. Solutions for the mixed-fractal flow model were derived in the Laplace domain and were validated among range of the reservoir parameters. The pressure transient behavior and production rate derivative were used to analyze flow regimes. The type curves show that the fluid flow in HFVWs can be divided into six main flow periods. Finally, effect of fractal parameters and SRV size on flow periods were also discussed. The results show that the SRV size and fractal parameters of fracture network have great effect on the former periods and fractal parameters of matrix mainly influence the later flow periods.
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Chin, E. R., and H. J. Green. "Effects of tissue fractionation on exercise-induced alterations in SR function in rat gastrocnemius muscle." Journal of Applied Physiology 80, no. 3 (March 1, 1996): 940–48. http://dx.doi.org/10.1152/jappl.1996.80.3.940.
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Because studies into exercise-induced alterations in sarcoplasmic reticulum (SR) Ca2+ sequestration have produced conflicting reports, we have hypothesized that the differences in SR Ca(2+)-adenosinetriphosphatase (ATPase) activity and Ca2+ uptake in SR fractions observed in different studies are due to different SR isolation techniques. To investigate this possibility, rat white and red gastrocnemius muscles from control and run animals were studied by using two conventional isolation techniques to obtain a crude microsomal fraction and an isolated SR vesicle (SRV) fraction. Indexes of CM and SRV function were compared with measurements from whole muscle homogenate. Treadmill running to exhaustion did not alter SR protein yields, percent SR extraction, or basal or Ca(2+)-ATPase purification in either fraction. Ca(2+)-activated ATPase activity was not altered by exercise in any of the fractions examined, but Ca2+ uptake was reduced in the homogenates (9.48 +/- 1.4 to 6.90 +/- 0.8 nmol . mg-1.min-1) and SRV fractions (84.0 +/- 11.5 to 50.7 +/- 14.0 nmol . mg-1.min-1) from the red gastrocnemius at free Ca2+ concentrations of 600-700 nM. These data indicate that reductions in SR Ca2+ uptake are dissociated from changes in Ca(2+)-ATPase in vitro and occur only in a specific population of vesicles. The mechanisms underlying these alterations are not known but may involve a reduction in the number of Ca(2+)-ATPase enzymes or a selective sedimentation of damaged vesicles in the SRV fraction.
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Punda, Hrvoje, Snjezana Mardesic, Natalija Filipovic, Ivona Kosovic, Benjamin Benzon, Marin Ogorevc, Ivana Bocina, Kresimir Kolic, Katarina Vukojevic, and Mirna Saraga-Babic. "Expression Pattern of 5-HT (Serotonin) Receptors during Normal Development of the Human Spinal Cord and Ganglia and in Fetus with Cervical Spina Bifida." International Journal of Molecular Sciences 22, no. 14 (July 7, 2021): 7320. http://dx.doi.org/10.3390/ijms22147320.
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The expression of 5-HT (serotonin) receptors (sr) was analyzed in the spinal cord and ganglia of 15 human conceptuses (5–10-weeks), and in the 9-week fetus with spina bifida. We used immunohistochemical method to detect sr-positive, apoptotic (caspase-3) and proliferating (Ki-67) cells, double immunofluorescence for co-localization with protein gene peptide (pgp) 9.5 and GFAP, as well as semiquantification and statistical measurements. Following the neurulation process, moderate (sr1 and sr2) and mild (sr3) expression characterized neuroblasts in the spinal cord and ganglia. During further development, sr1 expression gradually increased in the motoneurons, autonomic and sensory neurons, while sr2 and sr3 increased strongly in floor and roof plates. In the ganglia, sr3 expression increased during limited developmental period, while sr1 and sr2 increased throughout the investigated period. Co-expression of sr/pgp 9.5 characterized developing neurons, while sr/GFAP co-localized in the roof plate. In the spinal cord and ganglia of malformed fetus, weaker sr1 and sr2 and stronger sr3 expression accompanied morphological abnormalities. Anomalous roof plate morphology showed an excess of apoptotic and proliferating cells and increased sr3 expression. Our results indicate a human-species specific sr expression pattern, and the importance of sr1 in neuronal differentiation, and sr2 and sr3 in the control of the roof plate morphogenesis in normal and disturbed development.
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Sang, Yu, Sheng Lai Yang, Hao Chen, Feng Zhou, Kun Qian, and Wei Shi. "The Exploration and Recognition of Stimulated Reservoir Volume for Shale Gas in Sichuan Basin - Taking Well W201 as an Example." Advanced Materials Research 734-737 (August 2013): 1303–7. http://dx.doi.org/10.4028/www.scientific.net/amr.734-737.1303.
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In view of the formation characteristics of the Qiongzhusi formation in Sichuan Basin and using the Stimulated Reservoir Volume (SRV) concept for reference, fracturing design of well W201 is completed and field tests are successfully conducted. Through evaluation and analysis of the sand fracturing data and by combining some practical experience of the shale gas multistage fracturing in North America, the difference between SRV in shale gas and traditional fracturing is proposed and inspirations is obtained, reference and guidelines for the development of shale gas in China are supplied.
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Pichayapan, Preda, Phittayoot Chaleonpan, Peerapong Jitsangiam, and Pongsakorn Wongchana. "An Evaluation of Relationship with Polished Stone Value and Skid Resistance Value Based on a Laboratory Investigation." Key Engineering Materials 801 (May 2019): 410–15. http://dx.doi.org/10.4028/www.scientific.net/kem.801.410.
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Aggregates which are the main component of asphalt concrete play a major role in loading transfer and skid resistant performance of asphalt concrete. Therefore, reduction in friction resistance of aggregate would lead to a decrease in overall skid resistance of asphalt concrete which is a commonly used road pavement surface material. This research aims to evaluate relationship of aggregate friction capacity through the polished stone value and asphalt concrete skid resistance. In this study, a series of polished stone value tests on the study aggregate of limestone and sandy mudstone and British pendulum tests for skid resistance value of polished hot mix asphalt (HMA) slab. An accelerated polishing machine was used to create reduction of skid resistance of HMA slabs. Test results showed that reduction of polished stone value (PSV) of limestone 47.6% leads to a decrease of skid resistance value (SRV) approximately 43.8% of HMA slabs. Furthermore, 14.5% reduction of PSV of sandy mudstone causes a decrease of 20.3% SRV of HMA slabs. Finally, a relationship linear regression between PSV of aggregates and SRV of HMA slab was established.
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Mitchell, Jane L., Simon Hood, Edward T. Mee, Erin Wigglesworth, Meera Sethi, Ghazi Auda, Neil M. Almond, and Nicola J. Rose. "Simian T-cell lymphotropic virus type I alters the proviral load and biodistribution of simian retrovirus type 2 in co-infected macaques, supporting advancement of immunosuppressive pathology." Journal of General Virology 94, no. 3 (March 1, 2013): 623–33. http://dx.doi.org/10.1099/vir.0.046078-0.
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The infection dynamics and pathology of a retrovirus may be altered by one or more additional viruses. To investigate this further, this study characterized proviral load, biodistribution and the immune response in Macaca fascicularis naturally infected with combinations of simian retrovirus type 2 (SRV-2) and simian T-cell lymphotropic virus type I (STLV-I). As the mesenteric lymph node (MLN) and the spleen have been implicated previously in response to retroviral infection, the morphology and immunopathology of these tissues were assessed. The data revealed a significant change in SRV-2 biodistribution in macaques infected with STLV-I. Pathological changes were greater in the MLN and spleen of STLV-I-infected and co-infected macaques compared with the other groups. Immune-cell populations in co-infected macaque spleens were increased and there was an atypical distribution of B-cells. These findings suggest that the infection dynamics of each virus in a co-infected individual may be affected to a different extent and that STLV-I appears to be responsible for enhancing the biodistribution and associated pathological changes in SRV-2 in macaques.