Machine Learning Uncovers the Universe's Hidden Gems: A Comprehensive Catalogue of CIV Absorption Lines in SDSS DR12

We assemble the largest CIV absorption line catalogue to date, leveraging machine learning, specifically Gaussian processes, to remove the need for visual inspection for detecting CIV absorbers. The catalogue contains probabilities classifying the reliability of the absorption system within a quasar spectrum. Our training set was a sub-sample of DR7 spectra that had no detectable CIV absorption in a large visually inspected catalogue. We used Bayesian model selection to decide between our continuum model and our absorption-line models. Using a random hold-out sample of 1301 spectra from all of the 26,030 investigated spectra in DR7 CIV catalogue, we validated our pipeline and obtained an 87% classification performance score. We found good purity and completeness values, both ~80%, when a probability of ~95% is used as the threshold. Our pipeline obtained similar CIV redshifts and rest equivalent widths to our training set. Applying our algorithm to 185,425 selected quasar spectra from SDSS DR12, we produce a catalogue of 113,775 CIV doublets with at least 95% confidence. Our catalogue provides maximum a posteriori values and credible intervals for CIV redshift, column density, and Doppler velocity dispersion. We detect CIV absorption systems with a redshift range of 1.37 $\!-\!$ 5.1, including 33 systems with a redshift larger than 5 and 549 absorbers systems with a rest equivalent width greater than 2 A at more than 95% confidence. Our catalogue can be used to investigate the physical properties of the circumgalactic and intergalactic media.Comment: 18 pages, 25 figures, 3 table

{5,5′-Bis(diethyl­amino)-2,2′-[(2,2-dimethyl­propane-1,3-di­yl)bis­(nitrilo­methanylyl­idene)]diphenolato}dioxido­molybdenum(VI)

In the title compound, [Mo(C27H38N4O2)O2], the MoVI atom is coordinated by two oxide O atoms and by two O and two N atoms of the tetra­dentate Schiff base ligand in a distorted octa­hedral geometry. The Mo—N bond trans to a terminal oxide group is significantly longer than the other Mo—N bond, which is attributed to the strong trans effect of the oxide O atom. The dihedral angle formed between the substituted benzene rings is 71.79 (14)°. One of the ethyl groups is disordered over two sets of sites, with a refined site-occupancy ratio of 0.588 (18):0.412 (18)

PRIYA: A New Suite of Lyman-alpha Forest Simulations for Cosmology

We present the PRIYA suite of cosmological simulations, based on the code and hydrodynamic model of the ASTRID simulation, and designed for cosmological analyses of the Lyman-$\alpha$ forest. Our simulation suite spans a $9$-dimensional parameter space, including $4$ cosmological parameters and $5$ astrophysical/thermal parameters. We have run $48$ low fidelity simulations with $1536^3$ particles in a $120$ Mpc/h box and $3$ high fidelity simulations with $3072^3$ particles in a $120$ Mpc/h box. All our simulations include a full physics model for galaxy formation, including supernova and AGN feedback, and thus also contain a realistic population of DLAs. We advance on earlier simulations suites by larger particle loads, by incorporating new physical models for patchy hydrogen and helium reionization, and by self-consistently incorporating a model for AGN feedback. We show that patchy helium reionization imprints an excess in the 1D flux power spectrum on large scales, which may allow future measurements of helium reionization bubble sizes. Simulation parameters are chosen based on a Latin hypercube design and a Gaussian process is used to interpolate to arbitrary parameter combinations. We build a multi-fidelity emulator for the 1D flux power spectrum and the mean IGM temperature. We show that our final interpolation error is $< 1\%$ and that our simulations produce a flux power spectrum converged at the percent level for $z=5.4$ - $2.2$. Our simulation suite will be used to interpret Lyman-$\alpha$ forest 1D flux power spectra from SDSS and future DESI data releases.Comment: 24 pages, 11 figures, submitted to JCA

Studying Quasar Spectra with Machine Learning in Sloan Digital Sky Survey

In this thesis, we designed an algorithm to provide robust selection criteria in the parameterspace of measured properties of quasars. Our method combines the prior knowledge of an expert observer with what unsupervised machine learning understands about the underlying structures in the data to get a data-driven boundary in the multi-dimensional parameter space of quasar physical properties. We did that by quantifying the dissimilarity of our target group to the majority of the quasars in our data set. Our versatile method can select a cluster of similar data points that are located in statistically significant lower-density regions of the parameter space. We could find more quasars in the class of extremely red quasars and show our new sample has even more exotic outflow behavior. Our final selection produces three times more quasars with visually verified CIV broad absorption line feature, which is the signature of outflow, than the previous extremely red quasar sample. Our method is very useful in selecting the most important follow-up targets for observing red quasars. In the second project, we could assemble the largest CIV absorption line catalogue to date. By providing a probability for the existence of absorption systems in a quasar spectrum that viis a by-product of our Bayesian model selection and Gaussian Processes methods, we removed the need for visual inspection which is essential in dealing with the upcoming surveys with millions of spectra. After carefully validating our method by comparing a subset of the spectra inspected in the largest visually inspected CIV catalog to what our method predicts, we could find 113,775 CIV absorption systems with at least 95% confidence among 185,425 selected quasar spectra from SDSS DR12. We obtain a posterior distribution for column density, velocity dispersion, and absorption redshift for each investigated spectrum which can be used to get the maximum a posteriori value and the credible interval. Our method is specifically useful when we want to obtain information from low signal-to-noise ratio data

بررسی زندگی حكیم ابن بطلان و كتاب «تقویم‌الصحه» وی

Ebn-Batlan can be assumed one of the great physician of the 5th hijri century up to now, whose medical experiments and works were introduced as reliable references in most of the medicine history. He was skillful in wisdom and medicine and also in curing illnesses. He lived in 5th century and died in the middle of that. His books and works were so influencing in history of medicine particularly in the east of Islamic region. He has written nearly 13 books and articles. His book "Taghvim al-Sehha" has special importance besides his other medical works. The aim of this study is trying to introduce scientific and medical characteristics of Ebn-Batlan and his important works and some of his innovations as well. Ebn-Batlan, in medicine, used a combination of his earlier medicine’s methods and his updated experiences. He, nearly 900 years ago, stated the issues in medicine and curing illnesses in his book (Taghvim-al-Sehha) which are still medicine science’s issues and recommended and emphasized by medicine societies. Thus, research in the field of biography, medical methods and his health recommendations and other traditional medicine sages would be useful in introducing this great sage to the medicine world and researches of medicine history. Study and investigating on their used treatment methods could be helpful in distinguishing and curing the various diseases as well.ابن بطلان را می‌توان در زمره پزشکان بزرگ و معتبر قرن پنجم هجری به بعد دانست که آثار و تجربیات پزشکی وی، به عنوان مأخذی مستند و قابل قبول در ادوار تاریخ طب مطرح بوده است. وی در حکمت و طب، بسیار توانا و در درمان بیماری‌ها بسیار مهارت داشته است. محدوده زمانی زندگی وی در قرن پنجم هجری و وفات وی در اواسط نیمه دوم همین قرن بوده است. کتب و آثار او در تاریخ طب مخصوصاً در شرق قلمرو اسلامی بسیار مؤثر بوده است. قریب 13 کتاب، رساله و مقاله از وی در کتب تاریخی بیان شده است. در میان آثار طبی ابن بطلان، کتاب «تقویم‌الصحه» از اهمیت ویژه‌ای برخوردار است. در این پژوهش قصد داریم، شخصیت علمی و طبی، نوآوری‌ها و کتاب «تقویم‌الصحه» ابن بطلان را معرفی نماییم. ابن بطلان در طب، به صورت ترکیبی از شیوه‌های درمانی اطبای قبل از خود و تجربیات به‌روز خود استفاده می‌کرده است. او در حدود نهصد سال قبل مسائلی را در طب و درمان بیماری‌ها در کتاب «تقویم‌الصحه» بیان نموده که امروزه هم از مشکلات علم پزشکی بوده و از طرف مجامع پزشکی مورد توصیه و تأکید می‌باشد. پژوهش در خصوص زندگی‌نامه و شیوه‌های درمانی و توصیه‌های بهداشتی ـ پزشکی این حکیم و سایر حکمای طب سنتی می‌تواند در شناسایی این دانشمندان بزرگ، به جهان پزشکی و پژوهشگران تاریخ پزشکی مفید واقع شود. همچنین پژوهش و بررسی روش‌های درمانی مورد استفاده آن‌ها در تشخیص و درمان بیماری‌های مختلف راهگشا خواهد بود

Integrated control and monitoring of a smart charging station witha proposed data exchange protocol

Expansion of electric vehicles’ (EVs’) charging stations is an unavoidable requirement in sustainable cities. Provision of safe protection and control infrastructure is one of the most important requirements for a reliable charging station. In this direction, a centralized protection, control and monitoring unit (PCMU) for smart charging stations is proposed here. PCMU communicates with chargers of the station, protective devices (e.g. relays and circuit breakers), local generating units and all other devices installed at the charging station to determine the station status and to detect/locate faults that may occur in the supply grid of the station. The PCMU includes a self-healing technique which is one of the specialties of smart systems that assists network reliability to increase. One of the major contributions of this research is to propose a protocol for data exchange between the PCMU and the other components similar to the logic used in standard of IEC 61850. Also, potential impacts of implementation of the proposed unit on the most-widely used reliability indices are discussed. The proposed protection strategy is examined via two case studies

One-year prevalence and the association between SARS-CoV-2 cycle threshold, comorbidity and outcomes in population of Babol, North of Iran (2020-2021).

Background: The present study aimed to investigate the one-year prevalence of SARS-CoV-2, common comorbidities and demographic information among negative- and positive rRT-PCR in health care workers (HCW), hospitalized and outpatients. Also, the association between SARS-CoV-2 cycle threshold (Ct) and the outcomes of patients were analyzed in Babol, northern Iran. Methods: This large&#160;retrospective cross-sectional study was performed between March 2020 and March 2021. The records of 19232 hospitalized, outpatients and HCW suspected to COVID-19 were collected from teaching hospitals in the North of Iran. Results: Out of the 19232 suspected to COVID-19 patients, 7251 (37.7) had a positive rRT-PCR result; 652 (9), 4599 (63.4) and 2000 (27.6) of those were categorized as HCW, hospitalized and outpatients, respectively. Moreover, between the hospitalized and the outpatient group, 10.2 and 0.8 cases died, whereas no death cases were reported in the HCW. Furthermore, it seems that death rate was significantly different between the three groups of Ct value, the highest mortality in those with Ct between 21 and 30 (group B=7.6) and the lowest in the group with the highest Ct (between 31 and 40 = 5.5) (p&#60;0.001). Conclusion: In summary, 37.7 of cases were positive for SARS-CoV-2; of which, 63.4, 27.6 and 9 were hospitalized, outpatients and HCW, respectively. With regard to the mortality rate in hospitalized patients and the significant association with Ct under 20 and 30, it seems that the early detection and the initial quantification of SARS-CoV-2 in the first week of the conflict and therapeutic considerations to reduce the relative load can reduce the mortality rate