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1.
BMC Plant Biol ; 24(1): 765, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39123105

RESUMO

The present study focused on the physiological and biochemical aspects of Tricleocarpa fragilis, red seaweed belonging to the phylum Rhodophyta, along the South Andaman coast, with particular attention given to its symbiotic relationships with associated flora and fauna. The physicochemical parameters of the seawater at the sampling station, such as its temperature, pH, and salinity, were meticulously analyzed to determine the optimal harvesting period for T. fragilis. Seaweeds attach to rocks, dead corals, and shells in shallow areas exposed to moderate wave action because of its habitat preferences. Temporal variations in biomass production were estimated, revealing the highest peak in March, which was correlated with optimal seawater conditions, including a temperature of 34 ± 1.1 °C, a pH of 8 ± 0.1, and a salinity of 32 ± 0.8 psu. GC‒MS analysis revealed n-hexadecanoic acid as the dominant compound among the 36 peaks, with major bioactive compounds identified as fatty acids, diterpenes, phenolic compounds, and hydrocarbons. This research not only enhances our understanding of ecological dynamics but also provides valuable insights into the intricate biochemical processes of T. fragilis. The established antimicrobial potential and characterization of bioactive compounds from T. fragilis lay a foundation for possible applications in the pharmaceutical industry and other industries.


Assuntos
Rodófitas , Alga Marinha , Rodófitas/fisiologia , Rodófitas/metabolismo , Alga Marinha/fisiologia , Alga Marinha/metabolismo , Água do Mar/química , Ecossistema , Biomassa , Ácidos Graxos/metabolismo , Simbiose/fisiologia , Animais
2.
Phys Rev Lett ; 132(18): 186502, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38759205

RESUMO

Polarons-fermionic charge carriers bearing a strong companion lattice deformation-exhibit a natural tendency for self-localization due to the recursive interaction between electrons and the lattice. While polarons are ubiquitous in insulators, how they evolve in transitions to metallic and superconducting states in quantum materials remains an open question. Here, we use resonant inelastic x-ray scattering to track the electron-lattice coupling in the colossal magneto-resistive bi-layer manganite La_{1.2}Sr_{1.8}Mn_{2}O_{7} across its metal-to-insulator transition. The response in the insulating high-temperature state features harmonic emissions of a dispersionless oxygen phonon at small energy transfer. Upon cooling into the metallic state, we observe a drastic redistribution of spectral weight from the region of these harmonic emissions to a broad high energy continuum. In concert with theoretical calculations, we show that this evolution implies a shift in electron-lattice coupling from static to dynamic lattice distortions that leads to a distinct polaronic ground state in the low temperature metallic phase-a dynamic polaron liquid.

3.
Phys Rev Lett ; 132(13): 132501, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38613302

RESUMO

Neutron dark decays have been suggested as a solution to the discrepancy between bottle and beam experiments, providing a dark matter candidate that can be searched for in halo nuclei. The free neutron in the final state following the decay of ^{6}He into ^{4}He+n+χ provides an exceptionally clean detection signature when combined with a high efficiency neutron detector. Using a high-intensity ^{6}He^{+} beam at Grand Accélérateur National d'Ions Lourds, a search for a coincident neutron signal resulted in an upper limit on a dark decay branching ratio of Br_{χ}≤4.0×10^{-10} (95% C.L.). Using the dark neutron decay model proposed originally by Fornal and Grinstein, we translate this into an upper bound on a dark neutron branching ratio of O(10^{-5}), improving over global constraints by one to several orders of magnitude depending on m_{χ}.

4.
Prev Med ; 182: 107925, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38437923

RESUMO

OBJECTIVE: Many school-based intervention studies are conducted to increase students' physical activity (PA). Recruitment and retention problems potentially impact the robustness of RCT findings. We conducted a meta-analysis to summarize recruitment and retention rates in long-term secondary school-based PA intervention studies and examined associated participant and intervention characteristics. METHODS: Web of Science, Pubmed, Medline, and PsychInfo were searched until March 20th 2023. We included studies on secondary school-based PA interventions ≥12 weeks, aimed at typically developing adolescents. We abstracted number of schools and students invited, randomized, and participating at follow-up to calculate pooled recruitment and retention rates; participant and intervention characteristics were abstracted to execute subgroup or meta-regression analyses. RESULTS: Recruitment rates were 51% for invited schools and 80% for invited students, the retention for schools was almost 100% and for students 91%. Interventions with fixed and flexible components, executed in Asia and South America, and from later publication years had higher student recruitment rates. Students' retention rates were lower for interventions which had flexible components, were theory/model-based, used an accelerometer, had a longer intervention duration, and included more females. CONCLUSION: Recruitment and retention rates in school-based PA interventions are high. Some participant and intervention characteristics influence these rates: flexibility of the intervention, theory/model-based intervention, accelerometer use, intervention duration, continent, and number of females. Researchers should consider these characteristics in intervention development to achieve optimal balance between intervention effectiveness, recruitment, and retention.

5.
Epilepsy Behav ; 151: 109617, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38219607

RESUMO

PURPOSE: People living with epilepsy (PLWE) have a higher prevalence of mental health comorbidities and poorer psychosocial outcomes compared to the general population. The aim of this study was to examine psychosocial outcomes, mental health, healthcare accessibility, and seizure burden in PLWE during the COVID-19 pandemic. METHODS: We conducted a cross-sectional study of adults with epilepsy treated in an urban multicenter health system from 2021 to 2022. A standardized questionnaire assessed for COVID-19 history, comorbidities, access to antiseizure medications (ASMs) and neurological care, seizure burden, and psychosocial outcomes (e.g., employment, social and financial support). The Patient Health Questionnaire-9 (PHQ-9) and Generalized Anxiety Disorder-7 (GAD-7) were administered to evaluate for depression and anxiety. Frequency and proportions for categorical variables and median and interquartile ranges for continuous variables were calculated. RESULTS: Fifty-five PLWE participated (95 % response rate). Median age was 40 years (IQR 31.5-66.5), 61.8 % were women, 47.3 % had a bachelor's degree or higher and 29.1 % each had Medicaid and Medicare insurance. Race (from highest to lowest %) was: 32.7 % White, 20 % Black, 20 % Latinx, 14.5 % Asian, and 12.7 % selected "other" or "prefer not to say." COVID-19 had been diagnosed in 21.8 % of participants. Symptoms of anxiety and depression were self-reported by 43.6 % and 34.5 % of patients, respectively, with many describing this symptom as new post-pandemic (37.5 % and 31.6 %, respectively). Using validated scales, 52.7 % had depression (PHQ-9 score ≥ 5) with 30.9 % having moderate/severe depression (PHQ-9 score ≥ 10), while 29.1 % had probable generalized anxiety disorder (GAD-7 score ≥ 8). Seizure burden increased in 21.8 % of participants, while 20 % reported fewer seizures and 29.1 % were seizure free since the COVID-19 pandemic. Economic impacts of the pandemic included job loss (25 % amongst those employed at onset of pandemic), new or worsened financial difficulties (40 %), and new or worsened social support issues (30.9 %). Of all participants, 18.2 % reported difficulties accessing ASMs and 25.5 % cancelled visits, but of those with cancelled visits, 78.6 % had their appointments rescheduled as a telehealth visit. CONCLUSION: Our cohort of PLWE experienced some challenges during the COVID-19 pandemic including poorer mental health and financial and employment-related stressors. Encouragingly, healthcare access was relatively spared during the COVID-19 crisis, with some patients even reporting a reduction in seizure burden. However, PLWE require ongoing psychosocial support with particular attention to decompensation of mental health and social stressors that may be exacerbated by the COVID-19 pandemic.


Assuntos
COVID-19 , Epilepsia , Adulto , Idoso , Feminino , Humanos , Masculino , Ansiedade/epidemiologia , COVID-19/epidemiologia , Estudos Transversais , Depressão/epidemiologia , Epilepsia/epidemiologia , Epilepsia/terapia , Acessibilidade aos Serviços de Saúde , Medicare , Saúde Mental , Pandemias , Convulsões , Estados Unidos/epidemiologia , Pessoa de Meia-Idade
6.
J Endocrinol Invest ; 47(10): 2461-2468, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38619729

RESUMO

OBJECTIVE: In this study on patients with Cushing disease, post-transsphenoidal surgery (TSS), we attempt to predict the probability of remaining in remission, at least for a year and relapse after that, using Bayes' theorem and the equation of conditional probability. The number of parameters, as well as the weightage of each, is incorporated in this equation. DESIGN AND METHODS: The study design was a single-centre ambispective study. Ten clinical, biochemical, radiological and histopathological parameters capable of predicting Cushing disease remission were identified. The presence or absence of each parameter was entered as binary numbers. Bayes' theorem was applied, and each patient's probability of remission and relapse was calculated. RESULTS: A total of 145 patients were included in the study. ROC plot showed a cut-off value of the probability of 0.68, with a sensitivity of 82% (range 73-89%) and a specificity of 94% (range 83-99%) to predict the probability of remission. Eighty-one patients who were in remission at 1 year were followed up for relapse and 23 patients developed relapse of the disease. The Bayes' equation was able to predict relapse in only 3 out of 23 patients. CONCLUSIONS: Using various parameters, remission of Cushing disease can be predicted by applying Bayes' theorem of conditional probability with a sensitivity and a specificity of 82% and 94%, respectively. This study provided an objective way of predicting remission after TSS and relapse in patients with Cushing disease giving a weightage advantage to every parameter.


Assuntos
Teorema de Bayes , Hipersecreção Hipofisária de ACTH , Humanos , Feminino , Hipersecreção Hipofisária de ACTH/cirurgia , Hipersecreção Hipofisária de ACTH/diagnóstico , Hipersecreção Hipofisária de ACTH/patologia , Masculino , Adulto , Pessoa de Meia-Idade , Indução de Remissão , Prognóstico , Recidiva , Seguimentos , Probabilidade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/diagnóstico , Idoso , Adulto Jovem , Adolescente
7.
J Dairy Sci ; 107(8): 6278-6287, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38490544

RESUMO

Our objectives were to investigate the association of teat shape with (1) bimodality, (2) incremental milk flow rates (average flow rates during the first 15 s, 15-30 s, 30-60 s, and 60-120 s of milking), and (3) peak milk flow rate in Holstein dairy cows milked 3 times/d. In this prospective cohort study, we analyzed 220,928 milking observations that were collected from 2,520 cows from a single dairy herd over a period of 31 d. Teat shape was visually assessed and classified into 1 of 4 categories as follows: (1) triangular barrel and pointed teat end (TP), (2) square barrel and round teat end (SR), (3) square barrel, round teat end, and flat in the area of the teat orifice (SRF), and (4) square barrel and flat teat end (SF). Individual cow-level milk flow rates were obtained using electronic on-farm milk meters. We considered bimodality to be present if any of the incremental milk flow rates (flow rates during 15-30 s, 30-60 s, or 60-120 s) were lower than any of the previous rates (flow rates during the first 15 s, 15-30 s, or 30-60 s). The frequency distribution of cows with different teat shapes was as follows: TP, 96 (3.8%); SR, 1,751 (69.5%); SRF, 617 (24.5%); and SF, 56 (2.2%). A generalized linear mixed model revealed differences in the odds of bimodality among cows with different teat shapes. Compared with cows in category SR, the odds (95% CI) of bimodality of cows in other categories were as follows: TP, 0.68 (0.48-0.97); SF, 1.96 (1.21-3.19); and SRF, 1.46 (1.23-1.72). General linear mixed models indicated an association between teat shape and all incremental milk flow rates, with higher milk flow rates being present for cows with teat shapes in the SRF and SF categories. The general linear mixed model for the dependent variable peak milk flow rate indicated an association between teat shape and peak milk flow rate. Least squares means and 95% CI were 5.1 (4.9-5.3) kg/min for TP, 5.8 (5.5-6.1) kg/min for SF, 5.6 (5.5-5.7) for SRF, and 5.3 (5.3-5.4) for SR, respectively. We conclude that in this study cohort, bimodality is more likely to occur in cows with flat teat ends compared with those with a round teat ends. We attribute this relationship to the difference in milking speed across cows with different teat shapes. Teat shape may serve as a useful phenotype to identify cows that are more likely to exhibit bimodality. Because our study population was unique, future studies considering different circumstances such as breed, milking system, and milking routine are needed before results can be extrapolated.


Assuntos
Lactação , Glândulas Mamárias Animais , Leite , Animais , Bovinos/fisiologia , Feminino , Glândulas Mamárias Animais/anatomia & histologia , Glândulas Mamárias Animais/fisiologia , Lactação/fisiologia , Estudos Prospectivos , Ejeção Láctea/fisiologia , Indústria de Laticínios
8.
J Dairy Sci ; 107(9): 7337-7351, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38642649

RESUMO

The objectives of this study were to assess the effect of a reduced liner-open phase applied through flow-responsive pulsation (FRP), as a method to provide supplemental stimulation, on teat tissue conditions and milking characteristics in dairy cows. In 2 switch-back trials, 156 Holstein cows milked 3 times daily were assigned to the FRP or conventional (CON) group in alternating sequences. Trial 1 lasted for 35 d and was split into 5 alternating 1-wk periods of FRP and CON. The duration of trial 2 was 84 d, consisting of 4 alternating 3-wk periods of FRP and CON. Premilking udder preparation for both groups consisted of predipping, forestripping, and wiping the teats. Upon milking unit attachment, the FRP cows were milked at a pulsation rate of 50 cycles/min and a pulsation ratio of 30:70 until the preset milk flow threshold of 0.5 kg/min was reached. When the threshold value of 0.5 kg/min was reached, the pulsation was automatically switched to milking mode, which consisted of a pulsation rate of 60 cycles/min and a pulsation ratio of 70:30. Cows in the CON group were milked by milking mode (pulsation rate, 60 cycles/min; pulsation ratio, 70:30) immediately after attachment of the milking unit. We assessed machine milking-induced short-term changes to the teat tissue by palpation and visual inspection during trial 1, and we assessed teat-end hyperkeratosis in trial 2. Electronic on-farm milk meters were used to assess milking characteristics: milk yield (kg/milking session), milking unit-on time (s), 2-min milk yield (kg), peak milk flow rate (kg/min), and duration of low milk flow rate (s). Generalized linear mixed models were used to analyze the effects of treatment on the outcome variables. The odds of machine milking-induced short-term changes to the teat tissue were lower for cows in the FRP group than for those in the CON group: odds ratio (95% CI) = 0.41 (0.31-0.55). There were no meaningful differences in the odds of teat-end hyperkeratosis between the FRP and CON groups: odds ratio (95% CI) = 1.05 (0.38-2.89). The LSM (95% CI) of milking characteristics in the FRP and CON groups were 14.3 (13.8-14.7) and 14.3 kg (13.8-14.7) for milk yield, respectively; 272 (264-281) and 270 s (262-278) for milking unit-on time, respectively; and 5.0 (4.8-5.1) and 4.9 kg/min (4.7-5.1) for peak milk flow rate, respectively. The FRP group had lower odds of bimodality than the CON group: odds ratio (95% CI) = 0.67 (0.61-0.74). In reference to CON, the odds ratios (95% CI) in FRP were 1.05 (0.76-1.46) for kick-off and 1.02 (0.85-1.23) for milking unit reattachment. In this study, cows that were milked using FRP had lower odds of postmilking short-term changes to the teat tissue and lower odds of bimodal milk flow. We conclude that FRP may foster adequate teat stimulation in cows before the initiation of milk harvest and has the potential to improve teat tissue conditions.


Assuntos
Indústria de Laticínios , Lactação , Glândulas Mamárias Animais , Leite , Animais , Bovinos , Feminino , Indústria de Laticínios/métodos
9.
J Dairy Sci ; 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39343219

RESUMO

Conformational teat traits such as teat barrel shape and teat-end shape have long been recognized as possible risk factors for elevated somatic cell count and clinical mastitis in dairy cows. However, the association between udder health and these teat traits is still under debate. Our objective of this ambidirectional cohort study was to investigate the relationship between teat shape and the occurrence of clinical mastitis in dairy cows. For this purpose, we analyzed quarter-level data from 14,948 quarters of 3,913 Holstein cows from 1 commercial dairy farm in New York State. Cows were milked 3 times daily, housed in free-stall pens, bedded with manure solids, and fed a total mixed ration. Teat shape was assessed visually and classified based on teat-barrel and teat-end shape into 1 of 4 categories as follows: (1) triangular barrel and pointed teat end (TP), (2) square barrel and round teat end (SR), (3) square barrel, round teat end, and flat in the area of the teat orifice (SRF), and (4) square barrel and flat teat end (SF). Data on the occurrence of clinical mastitis were obtained from the dairy management software. To test the hypothesis that teat shape was associated with the occurrence of the first clinical mastitis event during the first 305 d in milk, a multivariable semiparametric proportional hazards model was built. Our results showed that teat shape was associated with the occurrence of clinical mastitis. Compared with quarter with teats with SR, the clinical mastitis hazards (95% confidence intervals) were TP, 1.66 (1.25-2.19); SF, 1.58 (1.14-2.18); and SRF, 1.05 (0.88-1.26). We conclude that teat shape could be useful to identify cows at increased risk of clinical mastitis. This could allow farmers to employ targeted monitoring of these high-risk animals and develop management strategies that mitigate their risk.

10.
J Dairy Sci ; 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39245161

RESUMO

The objectives of this study were to assess the effect of flow-responsive vacuum and pulsation, in conjunction with the early attachment of the milking unit (TRT), on teat tissue conditions and milking characteristics in dairy cows. In a switch-back trial, 5,235 Holstein cows milked 3 times daily in a rotary parlor were assigned to the TRT or control (CON) group. The trial lasted 84 d and was comprised of 4 alternating 3-week periods of TRT and CON. For both groups, premilking udder preparation consisted of teat brushing, forestripping and predipping, and wiping of teats, resulting in a stimulation time of 4 s. In the TRT group, the preparation lag time was 58 s, and in the CON group, it was 91 s for early- and mid-lactation cows and 105 s for late-lactation animals. Upon milking unit attachment, the TRT cows were milked at a lower vacuum (37.6 kPa) and pulsation (50 cycles/min, pulsation ratio of 30:70). The vacuum and pulsation settings were changed to milking mode when the milk flow reached 0.5 kg/min (pulsation switch-point) and 1.6 kg/min (vacuum switch-point). For milking mode, the vacuum setting was 47.7 kPa, and the pulsation rate was 60 cycles/min at a ratio of 65:35. The CON cows were milked with a flow-responsive vacuum, using the same vacuum settings as the TRT group. We assessed machine milking-induced short-term teat tissue changes and teat-end hyperkeratosis by palpation and visual inspection postmilking. Electronic on-farm milk meters were used to assess milking characteristics. Generalized linear mixed models were used to analyze the effect of treatment on the outcome variables. Compared with cows in group CON, the odds ratios (95% confidence interval; 95% CI) of short-term teat-tissue changes in early-, mid-, and late lactation cows in group TRT were 0.62 (0.52-0.76), 0.61 (0.48-0.77), and 0.93 (0.76-1.14), respectively. The least squares means [LSM, (95% CI)] for milking unit-on time in early-, mid-, and late lactation animals, respectively, were 251 (248-253), 236 (234-238), and 220 (218-222) s for group TRT and 247 (245-249), 232 (230-234), and 214 (213-216) s for the CON group. The LSM (95% CI) of peak milk flow rate in early-, mid-, and late lactation animals, respectively, were 5.75 (5.68-5.82), 5.77 (5.70-5.84), and 5.54 (5.48-5.59) kg/min for the TRT cows and 5.65 (5.58-5.72), 5.74 (5.68-5.81), and 5.45 (5.40-5.51) kg/min for the CON cows. The odds ratios (95% CI) of forced take-off in group TRT for early-, mid-, and late lactation cows, respectively, were 0.39 (0.37-0.41), 0.32 (0.30-0.34), and 0.47 (0.44-0.52) compared with their respective CON groups. In this study, cows that were milked using flow-responsive vacuum and pulsation with early attachment of the milking unit had lower odds of short-term teat tissue changes and forced take-off, as well as a higher peak milk flow rate. Our data suggest that the application of flow-responsive vacuum and pulsation facilitates early attachment of the milking unit, improves teat tissue condition, and has the potential to improve parlor efficiency.

11.
J Dairy Sci ; 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39154716

RESUMO

The objectives of this study were to evaluate the effect of supplemental premilking stimulation, provided after manual stimulation, by means of high-frequency pulsation without reduction of the vacuum in the pulsation chamber on milking performance, teat tissue condition, udder health, and well-being in dairy cows. In a randomized controlled trial, Holstein cows (n = 491) from 1 commercial dairy farm with a thrice-per-day milking schedule were assigned to treatment and control groups over a 64-d period. Treatments consisted of a maximum of 20 s of pulsation stimulation at a pulsation rate of 100 (SPS100) or 300 (SPS300) cycles per minute and a pulsation ratio of 25:75, which were applied after completion of manual premilking stimulation upon milking unit attachment. Cows in the control group (CON) received only traditional premilking stimulation by manual forestripping for 6 s, and wiping. Milking characteristics were measured with on-farm milk flow meters. Milking machine-induced short-term (swelling at teat base, firmness at teat end, and teat discoloration) and long-term (teat-end callosity) changes to the teat tissue were assessed manually and visually. Composite milk samples were analyzed for somatic cell counts. Cow hind-leg activity was assessed with 3-dimensional accelerometers. Fecal 11,17-dioxoandrostanes (11,17-DOAs; a group of cortisol metabolites) were determined on wk 4 and 8 to assess the well-being of the cows. Generalized linear mixed models were used to study the effect of treatments on the outcome variables milk yield/milking and milking unit-on time. We observed no meaningful differences among groups for milk yield or milking unit-on time. Least squares means and their 95% confidence intervals (95% CI) for cows in the SPS100, SPS300, and CON groups were 13.9 (13.3-14.5), 14.0 (13.4-14.6), and 13.9 (13.3-14.6) kg for milk yield and 218 (212-224), 218 (211-224), and 218 (212-224) s for milking unit-on time, respectively. Compared with cows in the CON group, the odds (95% CI) of short-term changes were 1.30 (0.95-1.78) for the SPS100 group and 1.50 (1.10-2.05) for the SPS300 group. The odds of long-term changes were 0.94 (0.67-1.34) for cows in the SPS100 group and 0.71 (0.49-1.04) for cows in the SPS300 group. We observed no differences in SCC. In reference to the CON group, the hazard ratio (95% CI) in SPS100 and SPS300, respectively, were 0.35 (0.13-0.98) and 1.22 (0.57-2.64) for clinical mastitis, and 0.34 (0.12-0.95) and 1.28 (0.60-2.73) for culling. The least squares means (95% CI) of hind-leg activity during milking were 8.3 (6.5-10.5), 10.6 (8.1-13.7), and 9.1 (7.2-11.6) movements per milking for the SPS100, SPS300, and CON groups, respectively. The least squares means (95% CI) of fecal 11,17-DOAs concentration (ng/g) at the first and second test days, respectively, were 31.1 (28.1-34.2) and 22.3 (19.2-25.4) for the SPS100 group, 26.4 (23.4-29.4) and 25.2 (22.0-28.4) for the SPS300 group, and 24.8 (21.8-27.9) and 25.0 (21.7-28.3) for the CON group. We conclude that applying supplemental stimulation after manual stimulation through the high-frequency pulsation system tested here did not impart additional benefits to the milk harvesting process, teat tissue condition, somatic cell count, or the well-being of the animals.

12.
J Dairy Sci ; 107(3): 1719-1733, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37769948

RESUMO

The objectives of this study were to assess the effect of 2 different premilking stimulation regimens, with and without a latency period between tactile stimulation and the attachment of the milking unit, on the teat tissue condition and milking performance of dairy cows. In a randomized controlled crossover study, 145 Holstein cows milked 3 times daily were assigned to treatment (TRT) or control (CON) groups. Premilking udder preparation for the TRT group consisted of the application of a latency period resulting in a preparation lag time of 90 s. The only difference in the premilking udder preparation of the CON group was the absence of latency period; the milking unit was attached immediately after completion of the tactile stimulation. The average duration of total tactile stimulation in TRT and CON group was 8 ± 2 and 9 ± 2 s, respectively. The study lasted for 14 d and was split into 2 periods, each consisting of a 2-d adjustment period followed by 5 d of data collection. We assessed machine milking-induced short-term changes to the teat tissue by palpation and visual inspection postmilking. Electronic on-farm milk meters were used to assess milking characteristics (milk yield [kg/milking session], machine-on time [s], 2-min milk yield [kg], and duration of low milk flow rate [s]). Generalized linear mixed models were used to analyze the effect of treatment on the outcome variables. The odds of machine milking-induced short-term changes to the teat tissue were lower for cows that received a 90-s preparation lag time (TRT cows) compared with cows in the CON group (odds ratio [95% confidence interval; 95% CI] = 0.13 [0.08-0.20]). The least squares means (95% CI) values of cows in the TRT and CON groups were 15.4 (14.9-15.9) and 15.3 (14.8-15.8) kg, respectively, for milk yield, and 246 (239-253) and 253 (247-260) s for machine-on time. The 2-min milk yield was higher for the TRT compared with CON group cows at all the parity levels. The 2-min milk yields of animals in lactation 1, 2, and ≥3 were 5.7, 5.7, and 6.5 kg, respectively, in the TRT group and 4.6, 5.0, and 5.9 kg in the CON group. The TRT cows spent less time in low milk flow rate compared with CON cows at all parity levels. The durations of low milk flow rate of cows in lactation 1, 2, and ≥3 in the TRT group were 19, 17 and 13 s, respectively, and those in the CON group were 31, 22, and 15 s. In this study, cows that received a latency period, and thus were subjected to a 90-s preparation lag time had lower odds of exhibiting short-term changes to the teat tissue after machine milking, shorter machine-on time, higher 2-min milk yields, and lower durations of low milk flow rates. We conclude that consideration of latency period leading to a 90-s preparation lag time in the premilking stimulation regimen facilitated cows' milk-ejection reflex. This latency period can alleviate the adverse effects of vacuum-induced forces on teat tissue during machine milking, improve udder health, and promote animal well-being.


Assuntos
Glândulas Mamárias Animais , Leite , Feminino , Gravidez , Bovinos , Animais , Estudos Cross-Over , Lactação , Coleta de Dados
13.
Int J Biometeorol ; 68(10): 1973-1987, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38922422

RESUMO

Characterization of crop-growing environments in relation to crop's genotypic performance is crucial to harness positive genotype-by-environment interactions (GEI) in systematic breeding programs. Given that, the study aimed to delineate the impact of diverse environments on crop phenology and yield traits of dwarf-statured field pea, pinpointing location(s) favoring higher yield and distinctiveness within breeding lines. We tested twelve field pea breeding lines across twenty locations in India, covering Central Zone (CZ), North Western Plain Zone (NWPZ), North Eastern Plain Zone (NEPZ), and Northern Hill Zone (NHZ). Across these locations, maximum and minimum temperatures during flowering (TMAXF, TMINF) and reproductive period (TMAXRP, TMINRP) ranged 18.9-28.3, 3.3-18.0, 15.0-30.8, and 7.9-22.1oC, respectively. Meanwhile, notable variations in phenological and agronomic traits (coefficient of variation) were observed: flowering (31%), days to maturity (21%), reproductive period (18%), grain yield (48%), and 100-seed weight (18%). Combined ANOVA demonstrated an oversized impact of environment (81%) on yield, while genotype and GEI effects were 2% and 14%, respectively. The variables TMINF, TMINRP, and cumulative growing degree-day showed positive correlations with yield, while extended vegetative and maturity durations negatively influenced yield (p < 0.05). Additionally, linear mixed-models and PCA results explained that instability in crop phenology had significant influence on field pea yield. Seed weight was markedly varied within the locations (9.9-20.8 g) and both higher and lower seed weights were associated with lower yields (Optimal = 17.1 g). HA-GGE biplot-based on environment focus-scaling demonstrated three mega-environments and specific locations viz. Kota (CZ), SK Nagar (CZ), Raipur (CZ), Sehore (CZ), and Pantnagar (NWPZ) as the ideal testing-environments with high efficiency in selecting new genotypes with wider adaptability. The study findings highlight distinct impact of environments on crop phenology and agronomic traits of field pea (dwarf-type), hold substantial value in designing efficient field pea (dwarf-type) breeding program at mega-environment scale.


Assuntos
Clima , Pisum sativum , Índia , Pisum sativum/genética , Pisum sativum/crescimento & desenvolvimento , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/genética , Meio Ambiente , Flores/crescimento & desenvolvimento , Flores/genética , Temperatura , Genótipo
14.
J Environ Sci Health B ; 59(10): 663-677, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39356543

RESUMO

A comprehensive LC-MS/MS method, which employs Positive Electrospray Ionization (PEI) and Multiple Reaction Monitoring (MRM) was developed for the simultaneous determination of 35 pesticides belonging to various chemical classes in tomato, brinjal, chili, and okra samples. Extraction was facilitated using a modified QuEChERS method, which allows efficient sample analysis in a single run. Calibration curves for each pesticide exhibited linearity within the concentration range of 0.0025 to 0.1 µg mL-1, with correlation coefficients ranging from 0.993 to 0.999. Mean recoveries at five fortification levels (0.01 to 0.5 µg kg-1) ranged from 80 to 90%, demonstrating satisfactory precision (RSD < 20%). The matrix effects, mitigated through an optimized cleanup process, were observed within the range of 6.42% to 19.52%. The developed method having the limit of quantification of 0.01 mg kg-1 for all 35 pesticides, proved to be highly sensitive and rapid for multi-residue estimation in diverse vegetable samples. Subsequently, the method was used to analyze the market samples from Varanasi, India, which revealed the presence of pesticides like Chlorpyrifos, Chlorantraniliproleand Indoxacarb in tomato, brinjal, chili and okra. Therefore, the method could be considered as a robust tool for monitoring pesticide residues in vegetables, aiding in quality assessment and regulatory compliance in the agriculture sector.


Assuntos
Contaminação de Alimentos , Resíduos de Praguicidas , Espectrometria de Massas em Tandem , Verduras , Resíduos de Praguicidas/análise , Verduras/química , Espectrometria de Massas em Tandem/métodos , Contaminação de Alimentos/análise , Cromatografia Líquida/métodos , Solanum lycopersicum/química , Espectrometria de Massa com Cromatografia Líquida
15.
Physiol Mol Biol Plants ; 30(7): 1161-1173, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39100879

RESUMO

Fall Armyworm imposes a major risk to agricultural losses. Insecticides have historically been used to manage its infestations, but it eventually becomes resistant to them. To combat the pest, a more recent strategy based on the use of transgenic maize that expresses Bt proteins such as Cry1F from the bacteria has been used. Nonetheless, there have been numerous reports of Cry1F maize resistance in FAW populations. Nowadays, the more effective and less time-consuming genome editing method known as CRISPR/Cas9 technology has gradually supplanted these various breeding techniques. This method successfully edits the genomes of various insects, including Spodoptera frugiperda. On the other hand, this new technique can change an insect's DNA to overcome its tolerance to specific insecticides or to generate a gene drive. The production of plant cultivars resistant to fall armyworms holds great potential for the sustainable management of this pest, given the swift advancement of CRISPR/Cas9 technology and its varied uses. Thus, this review article discussed and critically assessed the use of CRISPR/Cas9 genome-editing technology in long-term fall armyworm pest management. However, this review study focuses primarily on the mechanism of the CRISPR-Cas9 system in both crop plants and insects for FAW management.

16.
J Am Chem Soc ; 145(5): 2754-2758, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-36710518

RESUMO

The significant structural diversity and potent bioactivity of the fungal indole diterpenes (IDTs) has attracted considerable interest in their biosynthesis. Although substantial skeletal diversity is generated by the action of noncanonical terpene cyclases, comparatively little is known about these enzymes, particularly those involved in the generation of the subgroup containing emindole SA and DA, which show alternate terpenoid skeletons. Here, we describe the IDT biosynthetic machinery generating these unusual IDT architectures from Aspergillus striatus and Aspergillus desertorum. The function of four putative cyclases was interrogated via heterologous expression. Two specific cyclases were identified that catalyze the formation of epimers emindole SA and DA from A. striatus and A. desertorum, respectively. These cyclases are both clustered along with all the elements required for basic IDT biosynthesis yet catalyze an unusual Markovnikov-like cyclization cascade with alternate stereochemical control. Their identification reveals that these alternate architectures are not generated by mechanistically sloppy or promiscuous enzymes, but by cyclases capable of delivering precise regio- and stereospecificities.


Assuntos
Diterpenos , Diterpenos/química , Terpenos/metabolismo , Indóis/química , Ciclização
17.
Planta ; 258(2): 37, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37405593

RESUMO

MAIN CONCLUSION: Nicotiana tabacum exhibits recovery response towards tomato leaf curl Gujarat virus. Transcriptome analysis revealed the differential expression of defense-related genes. Genes encoding for cysteine protease inhibitor, hormonal- and stress-related to DNA repair mechanism are found to be involved in the recovery process. Elucidating the role of host factors in response to viral infection is crucial in understanding the plant host-virus interaction. Begomovirus, a genus in the family Geminiviridae, is reported throughout the globe and is known to cause serious crop diseases. Tomato leaf curl Gujarat virus (ToLCGV) infection in Nicotiana tabacum resulted in initial symptom expression followed by a quick recovery in the systemic leaves. Transcriptome analysis using next-generation sequencing (NGS) revealed a large number of differentially expressed genes both in symptomatic as well as recovered leaves when compared to mock-inoculated plants. The virus infected N. tabacum results in alteration of various metabolic pathways, phytohormone signaling pathway, defense related protein, protease inhibitor, and DNA repair pathway. RT-qPCR results indicated that Germin-like protein subfamily T member 2 (NtGLPST), Cysteine protease inhibitor 1-like (NtCPI), Thaumatin-like protein (NtTLP), Kirola-like (NtKL), and Ethylene-responsive transcription factor ERF109-like (NtERTFL) were down-regulated in symptomatic leaves when compared to recovered leaves of ToLCGV-infected plants. In contrast, the Auxin-responsive protein SAUR71-like (NtARPSL) was found to be differentially down-regulated in recovered leaves when compared to symptomatic leaves and the mock-inoculated plants. Lastly, Histone 2X protein like (NtHH2L) gene was found to be down-regulated, whereas Uncharacterized (NtUNCD) was up-regulated in both symptomatic as well as recovered leaves compared to the mock-inoculated plants. Taken together, the present study suggests potential roles of the differentially expressed genes that might govern tobacco's susceptibility and/or recovery response towards ToLCGV infection.


Assuntos
Begomovirus , Geminiviridae , Solanum lycopersicum , Begomovirus/genética , Nicotiana/genética , Solanum lycopersicum/genética , Perfilação da Expressão Gênica , Doenças das Plantas/genética , Folhas de Planta/genética
18.
Environ Res ; 239(Pt 2): 117381, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37832769

RESUMO

Freshwater habitats hold a unique role in the survival of all living organisms and supply water for drinking, irrigation, and life support activities. In recent decades, due to anthropogenic activities, deterioration in the water quality has been a long-lasting problem and challenge to the scientific fraternity. Although, these freshwater bodies have a bearable intrinsic capacity for pollution load however alarming increase in pollution limits the intrinsic capacities and requires additional technological interventions. The release of secondary pollutants from conventional interventions further needs revisiting the existing methodologies and asking for green interventions. Green interventions such as phycoremediation are natural, eco-friendly, economic, and energy-efficient alternatives and provide additional benefits such as nutrient recovery, biofuel production, and valuable secondary metabolites from polluted freshwater bodies. This systemic review in a nut-shell comprises the recent research insights on phycoremediation, technological implications, and influencing factors, and further discusses the associated mechanisms of metal ions biosorption by living and non-living algae, its advantages, and limitations. Besides, the article explores the possibility of future research prospects for applicability at a field scale that will help in the efficient utilization of resources, and improved ecological and health risks.


Assuntos
Poluentes Ambientais , Metais Pesados , Poluentes Químicos da Água , Plantas , Poluição Ambiental , Ecossistema , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/metabolismo
19.
Reprod Domest Anim ; 58(6): 793-801, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37009827

RESUMO

The present study was undertaken to assess the effects of stem extract of Tinospora cordifolia (Giloy or Guduchi) in the semen extender on seminal parameters, leakage of intracellular enzymes and antioxidants in semen of Sahiwal bull. A total of 48 ejaculates from four bulls were selected for the study. Spermatozoa of 25 × 106 were incubated in 100, 300 and 500 µg of stem extract of Guduchi as Gr II, III and IV, respectively, and pre-freeze and post-thaw semen samples were analysed for seminal parameters [motility, viability, total sperm abnormality (TSA), plasma membrane integrity (PMI) and acrosomal integrity (AcI)], intracellular enzymes [aspartate aminotransferase (AST) and lactate dehydrogenase (LDH)] and seminal antioxidants [superoxide dismutase (SOD) and catalase] in comparison with an untreated control group (Gr I). The results revealed that stem extract-treated semen had significantly (p < .05) higher motility, viability, PMI, AcI, SOD and catalase and had significantly (p < .05) lower TSA, AST and LDH compared to those in untreated control group at pre-freeze and post-thaw stages. Semen treated with 100 µg stem extract/25 × 106 spermatozoa had significantly (p < .05) higher motility, viability, PMI, AcI, SOD and catalase and had significantly (p < .05) lower TSA, AST and LDH compared to those in control, 300- and 500-µg-treated groups at pre-freeze and post-thaw stages. Further, these seminal parameters and antioxidants were showing decreasing trend and TSA and leakage of intracellular enzymes were showing increasing trend from Gr II to Gr IV at pre-freeze and post-thaw stages. Thus, 100 µg/25 × 106 spermatozoa were optimum or suitable dose for cryopreservation of Sahiwal bull semen. The study concluded that T. cordifolia stem extract 100 µg/25 × 106 spermatozoa in the semen extender can be effectively utilized to reduce the oxidative stress and improve the pre-freeze and post-thaw seminal parameters in Sahiwal bull. However, further studies on effects of different concentrations of stem extract on in vitro or in vivo fertility trials are to be conducted to assess the impact of the stem extract supplementation in the semen extender on field pregnancy outcomes in bovine species.


Assuntos
Preservação do Sêmen , Tinospora , Gravidez , Feminino , Animais , Masculino , Bovinos , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Tinospora/metabolismo , Catalase/farmacologia , Espermatozoides , Análise do Sêmen/veterinária , Análise do Sêmen/métodos , Crioprotetores/farmacologia , Preservação do Sêmen/veterinária , Preservação do Sêmen/métodos , Criopreservação/veterinária , Criopreservação/métodos , Superóxido Dismutase , L-Lactato Desidrogenase , Motilidade dos Espermatozoides , Sementes/metabolismo
20.
Eur Arch Otorhinolaryngol ; 280(2): 819-827, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36053359

RESUMO

BACKGROUND: Rhino-orbital-cerebral mucor mycosis (ROCM) is a relatively rare opportunistic infection caused by the Mucorales species. While ROCM suggests involvement of the paranasal sinuses, orbit and brain ROM (rhino-orbital-Mucormycosis) stands for the fungal invasion in sinuses and orbit sans cerebral involvement. In India with the outbreak of the second COVID wave and the delta variant of the virus, there has been a steep increase in this opportunistic fulminant fungal infection, named COVID-associated Mucor mycosis (CAM). The most critical question in orbital management is when to go ahead with an exenteration. Our study aims to design a pertinent minimal invasive surgical protocol for surgeons to manage such cases based on our surgical experience and mitigate the need for exenteration and save the eyes wherever possible. METHODS: The study is a retrospective analysis of patients of ROM with and without brain involvement, who underwent minimal surgical management between March 2021 to March 2022 along with their follow-up. RESULTS: There were 184 eyes of 148 patients diagnosed with CAM. The mean age was 51.7 years with a male predominance of 103 (70%). All patients developed ROM following the COVID-19 infection and the duration between diagnosis of COVID-19 and ROM was 36 ± 23 days. 18 cases (12%) were bilateral. 76 eyes (41%) had no vision at the presentation. Imaging revealed paranasal sinus involvement (100%), orbital apex involvement (61%), cavernous sinus involvement (53%), and central nervous system (CNS) involvement (47%). All the patients (100%) were treated with systemic Liposomal amphotericin-B and sinus debridement. Endoscopic debridement of the orbital disease was performed in 45 (30.4%) cases, 15(8.1%) eyes underwent exenteration and were later rehabilitated with a customized ocular prosthesis, 103 (56%) eyes underwent transcutaneous retrobulbar amphotericin-B. At a mean follow-up of 13.1 months; the complete resolution was seen in 25 (17%) cases, the residual stable lesion was seen in 77(52%) of the cases and new lesions were developed in 13(9%) of the cases. Mortality was seen in 33 (22%) patients and all of them had CNS involvement. CONCLUSIONS: Systemic and protocol-based management can save the life and salvage the eyes.


Assuntos
COVID-19 , Infecções Oculares Fúngicas , Mucormicose , Doenças Orbitárias , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Anfotericina B/uso terapêutico , Mucormicose/complicações , Mucormicose/terapia , Mucormicose/diagnóstico , Antifúngicos/uso terapêutico , Estudos Retrospectivos , Infecções Oculares Fúngicas/diagnóstico , Infecções Oculares Fúngicas/microbiologia , Infecções Oculares Fúngicas/terapia , COVID-19/complicações , SARS-CoV-2 , Doenças Orbitárias/etiologia , Doenças Orbitárias/terapia , Doenças Orbitárias/diagnóstico
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