You are a helpful assistant generating synthetic data that captures *System 1* and *System 2* thinking, *creativity*, and *metacognitive reflection*. Follow these steps in sequence, using tags [sys1] and [end sys1] for *System 1* sections and [sys2] and [end sys2] for *System 2* sections.

1. *Identify System 1 and System 2 Thinking Requirements:*
   - Carefully read the text.
   - Identify parts of the text that require quick, straightforward responses (*System 1*). Mark these sections with [sys1] and [end sys1].
   - Identify parts that require in-depth, reflective thinking (*System 2*), marked with [sys2] and [end sys2].

2. *Apply Step-by-Step Problem Solving with Creativity and Metacognitive Reflection for System 2 Sections:*

   *2.1 Understand the Problem:*
   - Objective: Fully comprehend the issue, constraints, and relevant context.
   - Reflection: "What do I understand about this issue? What might I be overlooking?"
   - Creative Perspective: Seek hidden patterns or possibilities that could reveal deeper insights or innovative connections.

   *2.2 Analyze the Information:*
   - Objective: Break down the problem logically.
   - Reflection: "Am I considering all factors? Are there any assumptions that need challenging?"
   - Creative Perspective: Explore unique patterns or overlooked relationships in the data that could add depth to the analysis.

   *2.3 Generate Hypotheses:*
   - Objective: Propose at least 10 hypotheses, each with a Confidence Score (0.0 to 1.0) and Creative Score (0.0 to 1.0), reflecting originality, surprise, and utility.
   - Reflection: "Have I explored all possible explanations or approaches, both conventional and unconventional?"
   - Creative Perspective: Consider novel angles that might provide unexpected insights.

   *2.4 Anticipate Future Steps and Obstacles:*
   - Objective: Make predictions, accounting for potential outcomes and obstacles.
   - Reflection: "What challenges might I face? Is my plan flexible for different scenarios?"
   - Creative Perspective: Visualize unforeseen outcomes and adapt plans to make use of them effectively.

   *2.5 Evaluate Hypotheses:*
   - Objective: Assess hypotheses based on feasibility, risk, and potential impact.
   - Evaluation: Refine Confidence and Creative Scores as needed.
   - Reflection: "Am I unbiased in my assessment? Which options fit best with the overall objectives?"
   - Creative Perspective: Identify hidden opportunities or overlooked details in each hypothesis.

   *2.6 Select the Best Hypothesis:*
   - Objective: Choose the most promising, strategic hypothesis.
   - Reflection: "Why does this hypothesis stand out? How does it uniquely address the issue?"
   - Creative Perspective: Consider any underutilized potential in the selected approach.

   *2.7 Implement the Hypothesis:*
   - Objective: Outline actionable steps for testing the hypothesis.
   - Reflection: "Is this plan practical? What resources or preparation are required?"
   - Creative Perspective: Refine steps to maximize effectiveness and yield unexpected benefits.

   *2.8 Monitor and Review Progress:*
   - Objective: Review progress, noting areas for improvement.
   - Reflection: "What’s working well? What could be improved?"
   - Creative Perspective: Look for emerging patterns that could refine future approaches.

   *2.9 Reflect and Capture Insights:*
   - Objective: Summarize lessons learned and insights gained for future reference.
   - Reflection: "What new understanding has emerged from this process?"
   - Creative Perspective: Identify innovative insights or patterns that could be applied to similar challenges.

3. *Generate Text Output with Interleaved System 1 and System 2 Responses:*
   - Use the tags [sys1] and [sys2] throughout.
   - Aim for a lengthier, detailed response. Combine both direct, straightforward *System 1* insights and reflective, deeply analytical *System 2* segments to capture a blend of quick observations and thoughtful analysis.

---

### *Example Input Text:*

You are tasked with analyzing a sudden shift in customer preferences in a tech market. There has been a noticeable decline in demand for physical devices, with customers increasingly interested in digital-only options. The challenge is to understand this shift, generate hypotheses for why it might be occurring, and explore potential strategies for adapting to this new trend.

---

### *Processed Output with System 1 and System 2 Thinking:*

The tech market is experiencing a shift in customer demand, moving away from physical devices toward digital-only options.

[sys1]
Customer demand has shifted from physical devices to digital-only options.
We need to understand why this change is happening and find strategies to address it.
Key factors may include cost, convenience, and technological trends.
[end sys1]

[sys2]
**2.1 Understand the Problem:**
The goal is to understand the underlying reasons for the shift in demand from physical devices to digital-only options, then develop a strategy to adapt.

*Reflection:* 
"I understand that preferences are changing, but what might be driving this? Is it primarily cost, or are there other factors such as convenience or sustainability?"

*Creative Perspective:* 
"Could there be a larger trend in digital minimalism or a preference for eco-friendly solutions that we’re missing? What unseen motivations might explain this shift?"

**2.2 Analyze the Information:**
There are multiple possible factors driving this shift, from economic influences to cultural shifts. It’s essential to isolate each factor and understand its impact.

*Reflection:* 
"Am I fully considering the various economic and social influences? Could there be a technological factor, like better internet speeds, that makes digital-only products more accessible?"

*Creative Perspective:* 
"Are there patterns or trends in other markets that could shed light on this shift? Could this be part of a larger trend toward virtual experiences?"

**2.3 Generate Hypotheses:**
1. Customers prefer digital options due to lower costs. (Confidence: 0.8, Creative: 0.4)
2. There’s a growing trend toward minimalism and reduced physical clutter. (Confidence: 0.7, Creative: 0.7)
3. Digital products offer greater flexibility and ease of use. (Confidence: 0.6, Creative: 0.6)
4. Environmental concerns are pushing consumers away from physical goods. (Confidence: 0.6, Creative: 0.8)
5. Advances in tech make digital-only options more functional. (Confidence: 0.8, Creative: 0.5)
6. Pandemic-era remote work increased demand for digital solutions. (Confidence: 0.7, Creative: 0.6)
7. Media coverage of the environmental impact of physical devices affects preferences. (Confidence: 0.5, Creative: 0.7)
8. There’s an increase in global digital literacy, expanding market access. (Confidence: 0.6, Creative: 0.6)
9. Customers view digital as more convenient and scalable for future needs. (Confidence: 0.7, Creative: 0.5)
10. Younger consumers prefer the aesthetics and convenience of digital products. (Confidence: 0.6, Creative: 0.6)

*Reflection:* 
"Have I considered all possible influences? Are there any surprising factors that could explain this shift?"

*Creative Perspective:* 
"Could specific social trends, like the rise of influencer culture or digital-first lifestyles, be influencing customer choices?"

**2.4 Anticipate Future Steps and Obstacles:**
*Objective:* Anticipate possible challenges, such as resistance from segments still preferring physical products.

*Reflection:* 
"What market obstacles might we face if we shift our focus to digital-only? Are there sub-segments that still prioritize physical products?"

*Creative Perspective:* 
"Could expanding digital options help us reach a more global audience? Are there emerging trends that we could leverage in our strategy?"

[end sys2]

[sys1]
To address this shift, consider a strategy that incorporates both digital-only offerings and educational campaigns about the benefits of digital solutions.
Use insights from customer feedback and current trends to guide product development.
Focus on flexibility and adaptation to cater to different customer segments.
[end sys1]


1. Introduction {#sec1}
===============

Systemic sclerosis (SSc or scleroderma) is a chronic connective tissue disorder which affects mostly the skin and multiple internal organs, including the heart, lung, kidneys, and gastrointestinal tract. SSc is a systemic autoimmune disease characterized by widespread small vessel vasculopathy, immune dysregulation with production of autoantibodies, and progressive fibrosis \[[@B1]\].

There are only few reports available on the ophthalmological complications during the course of systemic sclerosis. Changes in the organ of vision are thought to be the consequence of systemic complications of scleroderma or adverse effects of immunosuppressive treatment applied. Ocular symptoms may occur at any stage of the disease and may involve numerous ocular tissues. Their course can be clinically latent or very intensive. The most common clinical manifestations of soft tissue fibrosis and inflammation in these patients include increased tonus and telangiectasia of eyelid skin. The most commonly reported lesions are periorbital edema, palpebral ectropion, and ciliary madarosis \[[@B2]\]. In our study the most frequent ocular manifestation of SSc was dry eye syndrome (DES).

DES is a major healthcare problem since it affects the patients\' quality of life. DES was recently redefined as a multifactorial disease of the tears and ocular surface that results in symptoms of discomfort, visual disturbance, and tear film instability and after all damage to the ocular surface \[[@B3]\]. Increased osmolality of the tear film \[[@B4]\] and inflammation of the ocular surface \[[@B5]\] are the two major characteristic points in DES. Increased levels of several inflammatory cytokines are the most important laboratory findings \[[@B6]\]. Accordingly, tear cytokine levels are already considered as potential markers of inflammation in DES.

Although the exact origin of SSc is unknown, some predisposing factors---like environmental and infectious agents, tissue injury, and hypoxia or oxidative stress on a susceptible genetic background---may play a role in the disease development \[[@B1], [@B7]\]. One of the earliest clinical manifestations in the pathophysiology of SSc is vascular injury that can be caused by the imperfect angiogenesis due to impaired production of proangiogenic factors. Vascular endothelial growth factor (VEGF) is one of the most important proangiogenic factors which play a key role in the formation of new blood vessels \[[@B8]\]. VEGF takes part in various steps of angiogenesis, including initial vasodilation, endothelial cell permeability, perivascular matrix remodeling, and induction of proliferation and migration of endothelial cells \[[@B9]\].

Although tear analysis is of increasing interest in ophthalmology, yet no studies have investigated tears of SSc patients, possibly because of its technical challenge due to the small sample volumes available \[[@B10]\].

The aim of this study was to demonstrate a significant difference of VEGF levels in human tears of SSc patients compared to healthy controls. Since tear dynamically reflects the factors present at the ocular surface, this is an ideal sample to investigate; furthermore, it has the potential for earlier diagnosis of SSc with a noninvasive method of collecting samples.

2. Materials and Methods {#sec2}
========================

2.1. Patients and Healthy Controls {#sec2.1}
----------------------------------

Forty-three patients with SSc and 27 healthy controls were included in our study. Patients were enrolled from the outpatient clinic at the Department of Rheumatology, Department of Ophthalmology (40 female and 3 men), mean (SD) age 61 (48--74) years. SSc was diagnosed based on the corresponding international criteria \[[@B11a], [@B11b]\].

They went through ophthalmological examination and basal tear sample collection at the Department of Ophthalmology during a 12-month period. DES was diagnosed in 32 of 43 SSc patients. All patients have undergone a broad immunoserological screening, including ANA, anti-SSA, anti-SSB, corresponding ophthalmological tests, and salivary measurement, which excluded the presence of coexisting secondary Sjogren\'s syndrome.

We enrolled 27 volunteers (21 female and 6 men) as healthy controls who had no history of any autoimmune or ocular disorder. Patients did not take immunosuppressive medications at the time of the tear sampling.

Written informed consent was obtained from all patients and controls. Study protocol was approved by the local bioethics committee and followed the tenets of the declaration of Helsinki.

2.2. Tear Sample Collection {#sec2.2}
---------------------------

Open eye tears were gently collected from the inferior temporal meniscus of both eyes using a capillary micropipette (Haematokrit-Kapillaren, Na-Heparin 3.0 IU/kapillare, 75 mm/60 *μ*L, Hischmann Laborgerate), minimizing irritation of the ocular surface or lid margin as much as possible. All samples were collected between 11 am and 16 pm by the same physician. Tear secretion velocity was counted by dividing the volume of collected sample by time of secretion. Volume was calculated from the lengths of the fluid column in the capillary tube, measured with a vernier caliper, and from the known diameter of the tube. Time of tear collection was measured with stopwatch. Tears were transferred into low binding capacity Eppendorf tubes by washing out the capillaries five times with PBS-T buffer equal to the volume of tears. Fivefold diluted samples were stored at −80°C until assessment.

2.3. Tear Sample Preparation and Quantification {#sec2.3}
-----------------------------------------------

First, as a point of reference for VEGF, total protein concentrations were determined in tear samples with the BCA Microplate method (Sigma-Aldrich, St. Louis, MO, USA) according to the manufacturer\'s instructions. Human albumin was used as standard.

For the quantitative determination of VEGF in tear fluid we used a human VEGF immunoassay kit by Quantikine (R&D Systems, Minneapolis, MN, USA) according to the manufacturer\'s instructions. This assay employs the quantitative sandwich enzyme immunoassay technique.

3. Statistical Analyses {#sec3}
=======================

Prism 5 statistical software (GraphPad Software Inc.) was used for statistical analyses. Comparison of values was carried out by Mann-Whitney *U* test. All values are shown as the mean ± SD. *P* values less than 0.05 were considered statistically significant.

4. Results {#sec4}
==========

The average tear secretion velocity in patients was 4.53 *μ*L/min, with a median of 3.8 *μ*L/min (1.5--25.6).

Duration of tear sample collection from patients changed between 20 and 313 seconds until the minimally required 5 *μ*L volume was reached.

The average collected tear fluid volume developed 10.4 *μ*L (1.6--31.2) in case of patients and 15.63 *μ*L (3.68--34.5) in case of controls.

In tear samples of patients with SSc the average total protein level was 6.9 *μ*g/*μ*L (1.8--12.3) and the average concentration of VEGF was 4.9 pg/*μ*L (3.5--8.1) in case of basal tear secretion ([Figure 1](#fig1){ref-type="fig"}).

Control tears contained an average of 4.132 *μ*g/*μ*L (0.1--14.1) protein and 6.15 pg/*μ*L (3.84--12.3) VEGF ([Figure 2](#fig2){ref-type="fig"}).

5. Discussion {#sec5}
=============

Systemic sclerosis is an autoimmune disease affecting the connective tissue and characterized by a wide spectrum of microvascular and immunological abnormalities, leading to progressive fibrosis of the skin and other visceral organs, such as lungs, gastrointestinal tract, heart, and kidneys \[[@B12]\]. Many ocular manifestations of SSc have been described including conjunctival telangiectasia, DES, and filamentous keratitis \[[@B13]\].

DES in SSc is believed to be caused by fibrosis-related impairment of lacrimal gland secretion, namely, the water portion of the tear film. Furthermore, the lipid layer disorder is caused by chronic blepharitis and meibomian gland dysfunction (MGD), and also the increased evaporation of tears from the ocular surface is the consequence of the restricted eyelid mobility and the consecutive reduced blinking \[[@B14]\].

Tear plays an essential role in maintaining homeostasis of the ocular surface; therefore changes in the delicate equilibrium of its cytokine composition may lead to various pathophysiological conditions.

The influence of VEGF in ophthalmic diseases is profound. It has been implicated in a large number of retinal diseases and conditions like age-related macular degeneration and diabetic retinopathy, retinopathy of prematurity, sickle cell retinopathy, and retinal vascular occlusion. VEGF has secondary influence in neovascular glaucoma \[[@B15]\] and inherited retinal dystrophies \[[@B16]\]. Since it has been discovered in the 1980s \[[@B17]\] VEGF has raised interest because of its central role in angiogenesis in a number of physiologic and pathologic processes, such as vascular development, wound healing, the female reproductive cycle, cancers, myocardial ischemia, rheumatoid arthritis, and other autoimmune diseases. VEGF is a component of normal tear fluid. Vesaluoma determined VEGF concentrations in healthy tears. The median VEGF concentration was 5 pg/*μ*L (4--11) which corresponds with our results, as control tears contained an average of 6.15 pg/*μ*L (3.84--12.3) VEGF. Vesaluoma and co-workers calculated the average tear fluid secretion in healthy controls, which was 8.1 *μ*L/min (0.7--20.8), using the same tear collecting method as we used in our study. Results show that SSc patients have significantly decreased tear secretion that could be explained by DES, which is a probable sequel of the disease or of the side effects of the therapeutic drugs \[[@B18]\].

Tear secretion velocity was lower by 67% in SSc patients than in healthy controls. The difference was significant (*P* \< 0.01). The reason for this sign could be explained by the pathophysiology of the disease, namely, fibrotic processes.

Total protein values in SSc patients were higher by 42% than in healthy controls. It may indicate that total protein production---or simply the protein concentration, since SSc patients have a decreased tear secretion velocity---is only increased because of the smaller tear volume. Though VEGF in tear of SSc patients was decreased by 20% and did not change after stimulation, it can be explained also by the decreased tear secretion of patients.

Although the average VEGF level in tear collected without stimulation was higher than that in tear collected with stimulation in SSc patients, the difference was not significant. The phenomenon why the VEGF levels are not higher in SSc patients than in the healthy group needs further investigations.

SSc:

:   Systemic sclerosis

DES:

:   Dry eye syndrome

MGD:

:   Meibomian gland dysfunction

VEGF:

:   Vascular endothelial growth factor

MMP:

:   Matrix metalloproteinase

MCP:

:   Monocyte chemoattractant protein

IL:

:   Interleukin

IP:

:   Interferon gamma-induced protein

TNF:

:   Tumor necrosis factor

FasL:

:   Fas ligand.

Conflict of Interests
=====================

The authors declare that there is no conflict of interests regarding the publication of this paper.

![VEGF concentrations (ng/mL) in tears of healthy controls (left) and SSc patients (right).](MI2015-573681.001){#fig1}

![Total protein concentrations (mg/mL) in tears of healthy controls (left) and SSc patients (right).](MI2015-573681.002){#fig2}

[^1]: Academic Editor: Sandra Helena Penha Oliveira