Notes, summaries, assignments, exams, and problems for Baccalaureate

1) DIJKSTRA (SSSP) — STEP TABLE (PAST-PAPER INSTANCE A)

Given edges: a→b(2), a→c(7), a→e(10), b→d(2), c→d(1), c→g(2), d→f(2), e→g(1), f→g(2). Source = a.
Rule: Pick unsettled vertex with minimum dist; relax outgoing edges.

Vertices:   a   b   c   d   e   f   g

Init:
Dist      = 0   2   7   ∞  10   ∞   ∞
S = ∅

Step 1: Pick a (min=0), S={a}
Relax from a: already set b=2, c=7, e=10
Dist      = 0   2   7   ∞  10   ∞   ∞

Step 2: Pick b (min=2), S={a,b}
Relax b→d: dist(d) = dist(b)+2 = 2+2 = 4
Dist      = 0   2   7   4  10   ∞   ∞

Step 3: Pick d (min=4), S={a,b,d}
Relax d→f: dist(f) = 4+2 = 6
Dist      = 0   2   7   4  10   6   ∞

Step 4: Pick f (min=6), S={a,b,d,f}
Relax f→g: dist(g) = 6+2 = 8
Dist

Meaning and Definitions of Sociology

Etymological: From Latin socius (companion/society) and Greek logos (study/science) – literally, the "science of society".

Scientific Study: It is a systematic, empirical study of human society, social behavior, patterns, and relationships, using scientific methods to understand social phenomena, unlike mere philosophical speculation.

Key Focus Areas: Social structure, social institutions (family, education, religion), social interaction, culture, and the impact of society on individual behavior.

Definitions of Sociology

• Auguste Comte (Father of Sociology): Defined sociology as the science of social phenomena, aiming to discover the laws governing society.
• M. Ginsberg: "Sociology is the study of human interactions

Template for Pros and Cons Essays

Follow these guidelines strictly to structure your argument effectively.

Introduction

[1. IDEA GENERAL] have become central to modern life. [2. IDEA ESPECÍFICA SOBRE EL TEMA]. For this reason, the advantages and disadvantages of [TEMA] have become a matter that deserves our attention.

The Advantages

On the one hand, [TEMA] is praised for its capacity to [VENTAJA PRINCIPAL]. This often results in [UN BENEFICIO CONCRETO Y TANGIBLE]. Moreover, it can [OTRA VENTAJA IMPORTANTE, preferiblemente de tipo social o personal].

The Disadvantages

On the other hand, [TEMA] is also criticised for its tendency to [DESVENTAJA PRINCIPAL]. A clear example is how it [MENCIONAR UN ASPECTO O MECANISMO CONCRETO], which frequently leads... Continue reading "Pros and Cons: A Balanced Analysis Framework" »

Irregular Verbs List (1–70)

This comprehensive list presents 70 essential irregular verbs. Study the four principal forms (Base Form, Past Simple, Past Participle, and Present Participle) alongside their Spanish meanings to improve your fluency.

1. sweep – swept – swept – sweeping – barrer
2. drink – drank – drunk – drinking – beber
3. ride – rode – ridden – riding – cabalgar/montar
4. fall – fell – fallen – falling – caer
5. sing – sang – sung – singing – cantar
6. set – set – set – setting – colocar
7. eat – ate – eaten – eating – comer
8. buy – bought – bought – buying – comprar
9. meet – met – met – meeting – conocer (gente)
10. know – knew – known – knowing – conocer (saber)
11. get – got – gotten

Big Cities or Small Villages?

Nerea (excited): Silvia, imagine us living in a big city — lights, cafés, subways, people everywhere! It’s so alive!

Silvia (smiling): Alive, yes… but also loud, crowded, and always rushing. I’d rather live in a small village.

Nerea (laughing): A village? What would you even do there all day?

Silvia: Plenty! Walk in nature, talk to neighbors, breathe clean air. Life feels real there.

Nerea: But I love the city’s energy! So many things to do — theaters, shops, concerts!

Silvia: And in a small village, you have time to think, to listen, to just be.

Nerea (teasing): You and your peace and quiet!

Silvia (laughing): And you and your noise and lights!

Nerea (pausing): Still… cities can be stressful. Always traffic,... Continue reading "The Great Debate: City Energy vs. Countryside Calm" »

Sample Size Calculation

To find what n must be:

n ≥ (Z_1-α/2 / MOE)² * p(1-p)

Wald Confidence Interval

SE^ = sqrt((p^ * (1 – p)) / n)

Odds Ratio Analysis

Calculated by criss-cross of 2x2 table.

Example: The odds for someone to smoke ≥ 5 cigarettes and have lung cancer is 3.40 times that of someone who smokes < 5 cigarettes daily to have lung cancer.

Fisher's Exact Test

Used when cell frequencies are < 5 in a 2x2 table. Tests for independence.

• H₀: Odds ratio = 1
• H_A: Odds ratio ≠ 1

Chi-Square Test of Independence

• H₀: The two variables are independent.
• H_A: The two variables are not independent.

Logit Model

To find the number of odds used in the model, find all combinations of levels (e.g., a 2x3 model has 6 combinations).

Exp(estimate) = odds for... Continue reading "Statistical Analysis Cheat Sheet: Formulas and Methods" »

Lab 8: Temperature and Microbial Growth

Key Concepts

• Psychrophiles grow best between 0–20°C. Often found in cold environments like glaciers.
• Mesophiles prefer 20–45°C. These include human pathogens like E. coli.
• Thermophiles thrive at 55°C or higher. They are often found in hot springs.

Materials and Their Functions

• Tryptic Soy Broth (TSB): A nutrient-rich medium that supports bacterial growth.
• Incubators set to different temperatures (4°C, 25°C, 37°C, 55°C): Used to simulate environmental conditions.
• Spectrophotometer (OD600): Measures turbidity (cloudiness) of a culture to estimate cell density.
• Classification by growth: “+++” indicates heavy growth; “0” means no growth.

In this lab, students investigated how temperature affects... Continue reading "Microbiology Lab Fundamentals: Growth, Metabolism, Genetics" »

Top Cloud Computing Providers

1. Amazon Web Services (AWS)

• Services: EC2, S3, RDS, Lambda, CloudFront, etc.
• Strengths: Market leader, wide global reach, and deep feature set.
• Used for: Hosting, storage, AI/ML, DevOps, and serverless computing.

2. Microsoft Azure

• Services: Azure VMs, Azure Blob Storage, Azure SQL, and Azure Functions.
• Strengths: Integration with Microsoft tools and hybrid cloud support.
• Used for: Enterprise solutions, .NET hosting, and hybrid infrastructure.

3. Google Cloud Platform (GCP)

• Services: Compute Engine, Cloud Storage, BigQuery, and App Engine.
• Strengths: Big Data and ML capabilities, plus a global fiber network.
• Used for: Data analytics, Kubernetes (GKE), and AI/ML workloads.

Cloud Computing Case Studies

Cloud as Infrastructure

Discovering Lucena: A Cultural Gem in Andalusia

Lucena is a city in the south of Spain, located in the province of Córdoba, Andalusia. It is a unique destination defined by its rich history and a harmonious blend of Christian, Muslim, and Jewish cultures.

Historical Significance and Landmarks

Lucena boasts a deep historical legacy. Once a vital center for the Jewish community, the town preserves its heritage within its historic quarter. Key landmarks include:

• Castillo del Moral: A medieval castle that now houses an informative museum.
• Church of San Mateo: A site renowned for its stunning architectural design.

Traditions and Gastronomy

Lucena is celebrated for its vibrant traditions and culinary excellence:

• Semana Santa (Holy Week): Features solemn

1. Cambio de tiempo verbal (Backshift)

Cambios en las palabras de tiempo

Cambios en pronombres

Preguntas